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Sample records for features demonstrating defects

  1. Feature matching method in shaped light mode VFD defect detection

    NASA Astrophysics Data System (ADS)

    Jin, Xuanhong; Dai, Shuguang; Mu, Pingan

    2010-08-01

    In recent years, Vacuum Fluorescent Display (VFD) module in the car audio panel has been widely used. However, due to process reasons, VFD display production process will produce defects, not only affect the appearance, but also affect the display correctly. So building a car VFD display panel defect detection system is of great significance. Machine vision technology is introduced into the automotive VFD display defect detection in order to achieve fast and accurate detection of defects. Shaped light mode is a typical flaw detection mode which is based on characteristics of vehicle VFD panel. According to the image features, learning of the gray matching and feature matching method, we integrated use of feature matching method and the gray level matching method to achieve defect detection.

  2. Successful demonstration of a comprehensive lithography defect monitoring strategy

    NASA Astrophysics Data System (ADS)

    Peterson, Ingrid B.; Breaux, Louis H.; Cross, Andrew; von den Hoff, Michael

    2003-07-01

    This paper describes the validation of the methodology, the model and the impact of an optimized Lithography Defect Monitoring Strategy at two different semiconductor manufacturing factories. The lithography defect inspection optimization was implemented for the Gate Module at both factories running 0.13-0.15μm technologies on 200mm wafers, one running microprocessor and the other memory devices. As minimum dimensions and process windows decrease in the lithography area, new technologies and technological advances with resists and resist systems are being implemented to meet the demands. Along with these new technological advances in the lithography area comes potentially unforeseen defect issues. The latest lithography processes involve new resists in extremely thin, uniform films, exposing the films under conditions of highly optimized focus and illumination, and finally removing the resist completely and cleanly. The lithography cell is defined as the cluster of process equipment that accomplishes the coating process (surface prep, resist spin, edge-bead removal and soft bake), the alignment and exposure, and the developing process (post-exposure bake, develop, rinse) of the resist. Often the resist spinning process involves multiple materials such as BARC (bottom ARC) and / or TARC (top ARC) materials in addition to the resist itself. The introduction of these new materials with the multiple materials interfaces and the tightness of the process windows leads to an increased variety of defect mechanisms in the lithography area. Defect management in the lithography area has become critical to successful product introduction and yield ramp. The semiconductor process itself contributes the largest number and variety of defects, and a significant portion of the total defects originate within the lithography cell. From a defect management perspective, the lithography cell has some unique characteristics. First, defects in the lithography process module have the

  3. Laser scatter feature of surface defect on apples

    NASA Astrophysics Data System (ADS)

    Rao, Xiuqin; Ying, Yibin; Cen, YiKe; Huang, Haibo

    2006-10-01

    A machine vision system for real-time fruit quality inspection was developed. The system consists of a chamber, a laser projector, a TMS-7DSP CCD camera (PULNIX Inc.), and a computer. A Meteor-II/MC frame grabber (Matrox Graphics Inc.) was inserted into the slot of the computer to grab fruit images. The laser projector and the camera were mounted at the ceiling of the chamber. An apple was put in the chamber, the spot of the laser projector was projected on the surface of the fruit, and an image was grabbed. 2 breed of apples was test, Each apple was imaged twice, one was imaged for the normal surface, and the other for the defect. The red component of the images was used to get the feature of the defect and the sound surface of the fruits. The average value, STD value and comentropy Value of red component of the laser scatter image were analyzed. The Standard Deviation value of red component of normal is more suitable to separate the defect surface from sound surface for the ShuijinFuji apples, but for bintang apples, there is more work need to do to separate the different surface with laser scatter image.

  4. Software for Demonstration of Features of Chain Polymerization Processes

    ERIC Educational Resources Information Center

    Sosnowski, Stanislaw

    2013-01-01

    Free software for the demonstration of the features of homo- and copolymerization processes (free radical, controlled radical, and living) is described. The software is based on the Monte Carlo algorithms and offers insight into the kinetics, molecular weight distribution, and microstructure of the macromolecules formed in those processes. It also…

  5. Classification, clinical features, and genetics of neural tube defects.

    PubMed

    Salih, Mustafa A; Murshid, Waleed R; Seidahmed, Mohammed Z

    2014-12-01

    Neural tube defects (NTDs) constitute a major health burden (0.5-2/1000 pregnancies worldwide), and remain a preventable cause of still birth, neonatal, and infant death, or significant lifelong handicaps. The malformations result from failure of the neural folds to fuse in the midline, and form the neural tube between the third and the fourth week of embryonic development. This review article discusses their classification, clinical features, and genetics. Most NTDs are sporadic and both genetic, and non-genetic environmental factors are involved in its etiology. Consanguinity was suggested to contribute to the high incidence of NTDs in several countries, including Saudi Arabia. Syndromes, often associated with chromosomal anomalies, account for <10% of all NTDs; but a higher proportion (20%) has been documented in Saudi Arabia. Genetic predisposition constitutes the major underlying risk factor, with a strong implication of genes that regulate folate one-carbon metabolism and planar cell polarity.

  6. Identification of biochemical features of defective Coffea arabica L. beans.

    PubMed

    Casas, María I; Vaughan, Michael J; Bonello, Pierluigi; McSpadden Gardener, Brian; Grotewold, Erich; Alonso, Ana P

    2017-05-01

    Coffee organoleptic properties are based in part on the quality and chemical composition of coffee beans. The presence of defective beans during processing and roasting contribute to off flavors and reduce overall cup quality. A multipronged approach was undertaken to identify specific biochemical markers for defective beans. To this end, beans were split into defective and non-defective fractions and biochemically profiled in both green and roasted states. A set of 17 compounds in green beans, including organic acids, amino acids and reducing sugars; and 35 compounds in roasted beans, dominated by volatile compounds, organic acids, sugars and sugar alcohols, were sufficient to separate the defective and non-defective fractions. Unsorted coffee was examined for the presence of the biochemical markers to test their utility in detecting defective beans. Although the green coffee marker compounds were found in all fractions, three of the roasted coffee marker compounds (1-methylpyrrole, 5-methyl- 2-furfurylfuran, and 2-methylfuran) were uniquely present in defective fractions.

  7. Morphological features (defects) in fuel cell membrane electrode assemblies

    NASA Astrophysics Data System (ADS)

    Kundu, S.; Fowler, M. W.; Simon, L. C.; Grot, S.

    Reliability and durability issues in fuel cells are becoming more important as the technology and the industry matures. Although research in this area has increased, systematic failure analysis, such as a failure modes and effects analysis (FMEA), are very limited in the literature. This paper presents a categorization scheme of causes, modes, and effects related to fuel cell degradation and failure, with particular focus on the role of component quality, that can be used in FMEAs for polymer electrolyte membrane (PEM) fuel cells. The work also identifies component defects imparted on catalyst-coated membranes (CCM) by manufacturing and proposes mechanisms by which they can influence overall degradation and reliability. Six major defects have been identified on fresh CCM materials, i.e., cracks, orientation, delamination, electrolyte clusters, platinum clusters, and thickness variations.

  8. Defective autophagy is a key feature of cerebral cavernous malformations

    PubMed Central

    Marchi, Saverio; Corricelli, Mariangela; Trapani, Eliana; Bravi, Luca; Pittaro, Alessandra; Delle Monache, Simona; Ferroni, Letizia; Patergnani, Simone; Missiroli, Sonia; Goitre, Luca; Trabalzini, Lorenza; Rimessi, Alessandro; Giorgi, Carlotta; Zavan, Barbara; Cassoni, Paola; Dejana, Elisabetta; Retta, Saverio Francesco; Pinton, Paolo

    2015-01-01

    Cerebral cavernous malformation (CCM) is a major cerebrovascular disease affecting approximately 0.3–0.5% of the population and is characterized by enlarged and leaky capillaries that predispose to seizures, focal neurological deficits, and fatal intracerebral hemorrhages. Cerebral cavernous malformation is a genetic disease that may arise sporadically or be inherited as an autosomal dominant condition with incomplete penetrance and variable expressivity. Causative loss-of-function mutations have been identified in three genes, KRIT1 (CCM1), CCM2 (MGC4607), and PDCD10 (CCM3), which occur in both sporadic and familial forms. Autophagy is a bulk degradation process that maintains intracellular homeostasis and that plays essential quality control functions within the cell. Indeed, several studies have identified the association between dysregulated autophagy and different human diseases. Here, we show that the ablation of the KRIT1 gene strongly suppresses autophagy, leading to the aberrant accumulation of the autophagy adaptor p62/SQSTM1, defective quality control systems, and increased intracellular stress. KRIT1 loss-of-function activates the mTOR-ULK1 pathway, which is a master regulator of autophagy, and treatment with mTOR inhibitors rescues some of the mole-cular and cellular phenotypes associated with CCM. Insufficient autophagy is also evident in CCM2-silenced human endothelial cells and in both cells and tissues from an endothelial-specific CCM3-knockout mouse model, as well as in human CCM lesions. Furthermore, defective autophagy is highly correlated to endothelial-to-mesenchymal transition, a crucial event that contributes to CCM progression. Taken together, our data point to a key role for defective autophagy in CCM disease pathogenesis, thus providing a novel framework for the development of new pharmacological strategies to prevent or reverse adverse clinical outcomes of CCM lesions. PMID:26417067

  9. Defective autophagy is a key feature of cerebral cavernous malformations.

    PubMed

    Marchi, Saverio; Corricelli, Mariangela; Trapani, Eliana; Bravi, Luca; Pittaro, Alessandra; Delle Monache, Simona; Ferroni, Letizia; Patergnani, Simone; Missiroli, Sonia; Goitre, Luca; Trabalzini, Lorenza; Rimessi, Alessandro; Giorgi, Carlotta; Zavan, Barbara; Cassoni, Paola; Dejana, Elisabetta; Retta, Saverio Francesco; Pinton, Paolo

    2015-11-01

    Cerebral cavernous malformation (CCM) is a major cerebrovascular disease affecting approximately 0.3-0.5% of the population and is characterized by enlarged and leaky capillaries that predispose to seizures, focal neurological deficits, and fatal intracerebral hemorrhages. Cerebral cavernous malformation is a genetic disease that may arise sporadically or be inherited as an autosomal dominant condition with incomplete penetrance and variable expressivity. Causative loss-of-function mutations have been identified in three genes, KRIT1 (CCM1), CCM2 (MGC4607), and PDCD10 (CCM3), which occur in both sporadic and familial forms. Autophagy is a bulk degradation process that maintains intracellular homeostasis and that plays essential quality control functions within the cell. Indeed, several studies have identified the association between dysregulated autophagy and different human diseases. Here, we show that the ablation of the KRIT1 gene strongly suppresses autophagy, leading to the aberrant accumulation of the autophagy adaptor p62/SQSTM1, defective quality control systems, and increased intracellular stress. KRIT1 loss-of-function activates the mTOR-ULK1 pathway, which is a master regulator of autophagy, and treatment with mTOR inhibitors rescues some of the mole-cular and cellular phenotypes associated with CCM. Insufficient autophagy is also evident in CCM2-silenced human endothelial cells and in both cells and tissues from an endothelial-specific CCM3-knockout mouse model, as well as in human CCM lesions. Furthermore, defective autophagy is highly correlated to endothelial-to-mesenchymal transition, a crucial event that contributes to CCM progression. Taken together, our data point to a key role for defective autophagy in CCM disease pathogenesis, thus providing a novel framework for the development of new pharmacological strategies to prevent or reverse adverse clinical outcomes of CCM lesions.

  10. Evolution of pulmonary perfusion defects demonstrated with contrast-enhanced dynamic MR perfusion imaging.

    PubMed

    Howarth, N R; Beziat, C; Berthezène, Y

    1999-01-01

    Pulmonary perfusion defects can be demonstrated with contrast-enhanced dynamic MR perfusion imaging. We present the case of a patient with a pulmonary artery sarcoma who presented with a post-operative pulmonary embolus and was followed in the post-operative period with dynamic contrast-enhanced MR perfusion imaging. This technique allows rapid imaging of the first passage of contrast material through the lung after bolus injection in a peripheral vein. To our knowledge, this case report is the first to describe the use of this MR technique in showing the evolution of peripheral pulmonary perfusion defects associated with pulmonary emboli.

  11. Modeling of light scattering from features on and within films and light scatter from epitaxial silicon defects

    NASA Astrophysics Data System (ADS)

    Zhang, Haiping

    The detection of particles and defects on or within films deposited on wafers using light scattering is of great interest to the semiconductor industry. Numerical calculation of light scattering characteristics from these features is very useful to the development and calibration of wafer inspection tools. A model and associated code is developed by using a modification of the discrete-dipole approximation (DDA) method to compute the light scattering from a feature with arbitrary shape on or within a filmed surface. The reflection interaction matrix is modified with the Sommerfeld integrals for filmed surfaces. Three-dimensional fast Fourier transform technique is used for accelerating the computation of light scatter from features associated with layered surfaces using the DDA method. Far field scatter is calculated approximately based on the reaction theorem. Model predictions of scattering signatures are compared with experimental results and other numerical models. Comparisons show good agreement for the cases considered, which demonstrates the accuracy and validity of the model. An epitaxial silicon wafer defect sample was fabricated containing typical epitaxial wafer defects such as epitaxial stacking faults, spikes and mounds. Atomic force microscopy was used to determine their physical sizes and shapes. The optical scattering characteristics of these epitaxial silicon wafer defects were studied using the numerical model. A method to discriminate epitaxial crystalline defects and particles is proposed.

  12. Patient fibroblasts-derived induced neurons demonstrate autonomous neuronal defects in adult-onset Krabbe disease

    PubMed Central

    Choi, Won Jun; Oh, Ki-Wook; Nahm, Minyeop; Xue, Yuanchao; Choi, Jae Hyeok; Choi, Ji Young; Kim, Young-Eun; Chung, Ki Wha; Fu, Xiang-Dong; Ki, Chang-Seok; Kim, Seung Hyun

    2016-01-01

    Krabbe disease (KD) is an autosomal recessive neurodegenerative disorder caused by defective β-galactosylceramidase (GALC), a lysosomal enzyme responsible for cleavage of several key substrates including psychosine. Accumulation of psychosine to the cytotoxic levels in KD patients is thought to cause dysfunctions in myelinating glial cells based on a comprehensive study of demyelination in KD. However, recent evidence suggests myelin-independent neuronal death in the murine model of KD, thus indicating defective GALC in neurons as an autonomous mechanism for neuronal cell death in KD. These observations prompted us to generate induced neurons (iNeurons) from two adult-onset KD patients carrying compound heterozygous mutations (p.[K563*];[L634S]) and (p.[N228_S232delinsTP];[G286D]) to determine the direct contribution of autonomous neuronal toxicity to KD. Here we report that directly converted KD iNeurons showed not only diminished GALC activity and increased psychosine levels, as expected, but also neurite fragmentation and abnormal neuritic branching. The lysosomal-associated membrane proteins 1 (LAMP1) was expressed at higher levels than controls, LAMP1-positive vesicles were significantly enlarged and fragmented, and mitochondrial morphology and its function were altered in KD iNeurons. Strikingly, we demonstrated that psychosine was sufficient to induce neurite defects, mitochondrial fragmentation, and lysosomal alterations in iNeurons derived in healthy individuals, thus establishing the causal effect of the cytotoxic GALC substrate in KD and the autonomous neuronal toxicity in KD pathology. PMID:27780934

  13. Demonstrating non-Abelian braiding of surface code defects in a five qubit experiment

    NASA Astrophysics Data System (ADS)

    Wootton, James R.

    2017-03-01

    Currently, the mainstream approach to quantum computing is through surface codes. One way to store and manipulate quantum information with these to create defects in the codes which can be moved and used as if they were particles. Specifically, they simulate the behaviour of exotic particles known as Majoranas, which are a kind of non-Abelian anyon. By exchanging these particles, important gates for quantum computation can be implemented. Here we investigate the simplest possible exchange operation for two surface code Majoranas. This is found to act non-trivially on only five qubits. The system is then truncated to these five qubits, so that the exchange process can be run on the IBM 5Q processor. The results demonstrate the expected effect of the exchange. This paper has been written in a style that should hopefully be accessible to both professional and amateur scientists.

  14. Specific features of defect and mass transport in concentrated fcc alloys

    SciTech Connect

    Osetsky, Yuri N.; Béland, Laurent K.; Stoller, Roger E.

    2016-06-15

    We report that diffusion and mass transport are basic properties that control materials performance, such as phase stability, solute decomposition and radiation tolerance. While understanding diffusion in dilute alloys is a mature field, concentrated alloys are much less studied. Here, atomic-scale diffusion and mass transport via vacancies and interstitial atoms are compared in fcc Ni, Fe and equiatomic Ni-Fe alloy. High temperature properties were determined using conventional molecular dynamics on the microsecond timescale, whereas the kinetic activation-relaxation (k-ART) approach was applied at low temperatures. The k-ART was also used to calculate transition states in the alloy and defect transport coefficients. The calculations reveal several specific features. For example, vacancy and interstitial defects migrate via different alloy components, diffusion is more sluggish in the alloy and, notably, mass transport in the concentrated alloy cannot be predicted on the basis of diffusion in its pure metal counterparts. Lastly, the percolation threshold for the defect diffusion in the alloy is discussed and it is suggested that this phenomenon depends on the properties and diffusion mechanisms of specific defects.

  15. Specific features of defect and mass transport in concentrated fcc alloys

    DOE PAGES

    Osetsky, Yuri N.; Béland, Laurent K.; Stoller, Roger E.

    2016-06-15

    We report that diffusion and mass transport are basic properties that control materials performance, such as phase stability, solute decomposition and radiation tolerance. While understanding diffusion in dilute alloys is a mature field, concentrated alloys are much less studied. Here, atomic-scale diffusion and mass transport via vacancies and interstitial atoms are compared in fcc Ni, Fe and equiatomic Ni-Fe alloy. High temperature properties were determined using conventional molecular dynamics on the microsecond timescale, whereas the kinetic activation-relaxation (k-ART) approach was applied at low temperatures. The k-ART was also used to calculate transition states in the alloy and defect transport coefficients.more » The calculations reveal several specific features. For example, vacancy and interstitial defects migrate via different alloy components, diffusion is more sluggish in the alloy and, notably, mass transport in the concentrated alloy cannot be predicted on the basis of diffusion in its pure metal counterparts. Lastly, the percolation threshold for the defect diffusion in the alloy is discussed and it is suggested that this phenomenon depends on the properties and diffusion mechanisms of specific defects.« less

  16. A new automated spectral feature extraction method and its application in spectral classification and defective spectra recovery

    NASA Astrophysics Data System (ADS)

    Wang, Ke; Guo, Ping; Luo, A.-Li

    2017-03-01

    Spectral feature extraction is a crucial procedure in automated spectral analysis. This procedure starts from the spectral data and produces informative and non-redundant features, facilitating the subsequent automated processing and analysis with machine-learning and data-mining techniques. In this paper, we present a new automated feature extraction method for astronomical spectra, with application in spectral classification and defective spectra recovery. The basic idea of our approach is to train a deep neural network to extract features of spectra with different levels of abstraction in different layers. The deep neural network is trained with a fast layer-wise learning algorithm in an analytical way without any iterative optimization procedure. We evaluate the performance of the proposed scheme on real-world spectral data. The results demonstrate that our method is superior regarding its comprehensive performance, and the computational cost is significantly lower than that for other methods. The proposed method can be regarded as a new valid alternative general-purpose feature extraction method for various tasks in spectral data analysis.

  17. Feature extraction and band selection methods for hyperspectral imagery applied for identifying defects

    NASA Astrophysics Data System (ADS)

    Cheng, Xuemei; Yang, Tao; Chen, Yud-Ren; Chen, Xin

    2005-11-01

    An important task in hyperspectral data processing is to reduce the redundancy of the spectral and spatial information without losing any valuable details that are needed for the subsequent detection, discrimination and classification processes. Band selection and combination not only serves as the first step of hyperspectral data processing that leads to a significant decrease in computational complexity in the successive procedures, but also a research tool for determining optimal spectra requirements for different online applications. In order to uniquely characterize the materials of interest, band selection criteria for optimal band was defined. An integrated PCA and Fisher linear discriminant (FLD) method has been developed based on the criteria that used for hyperspectral feature band selection and combination. This method has been compared with other feature extraction and selection methods when applied to detect apple defects, and the performance of each method was evaluated and compared based on the detection results.

  18. Defects in doped LaGaO3 anionic conductors: linking NMR spectral features, local environments, and defect thermodynamics.

    PubMed

    Blanc, Frédéric; Middlemiss, Derek S; Gan, Zhehong; Grey, Clare P

    2011-11-09

    Doped lanthanum gallate perovskites (LaGaO(3)) constitute some of the most promising electrolyte materials for solid oxide fuel cells operating in the intermediate temperature regime. Here, an approach combining experimental multinuclear NMR spectroscopy with density functional theory total energy and GIPAW NMR calculations yields a comprehensive understanding of the structural and defect chemistries of Sr- and Mg-doped LaGaO(3) anionic conductors. The DFT energetics demonstrate that Ga-V(O)-Ga (V(O) = oxygen vacancy) environments are favored (vs Ga-V(O)-Mg, Mg-V(O)-Mg and Mg-O-Mg-V(O)-Ga) across a range y = 0.0625, 0.125, and 0.25 of fractional Mg contents in LaGa(1-y)Mg(y)O(3-y/2). The results are interpreted in terms of doping and mean phase formation energies (relative to binary oxides) and are compared with previous calculations and experimental calorimetry data. Experimental multinuclear NMR data reveal that while Mg sites remain six-fold coordinated across the range of phase stoichiometries, albeit with significant structural disorder, a stoichiometry-dependent minority of the Ga sites resonate at a shift consistent with Ga(V) coordination, demonstrating that O vacancies preferentially locate in the first anion coordination shell of Ga. The strong Mg-V(O) binding inferred by previous studies is not observed here. The (17)O NMR spectra reveal distinct resonances that can be assigned by using the GIPAW NMR calculations to anions occupying equatorial and axial positions with respect to the Ga(V)-V(O) axis. The disparate shifts displayed by these sites are due to the nature and extent of the structural distortions caused by the O vacancies.

  19. Field Demonstration of Electro-Scan Defect Location Technology for Condition Assessment of Wastewater Collection Systems

    EPA Science Inventory

    The purpose of the field demonstration program is to gather technically reliable cost and performance information on selected condition assessment technologies under defined field conditions. The selected technologies include zoom camera, electro-scan (FELL-41), and a multi-sens...

  20. Glycine decarboxylase deficiency causes neural tube defects and features of non-ketotic hyperglycinemia in mice

    PubMed Central

    Pai, Yun Jin; Leung, Kit-Yi; Savery, Dawn; Hutchin, Tim; Prunty, Helen; Heales, Simon; Brosnan, Margaret E.; Brosnan, John T.; Copp, Andrew J.; Greene, Nicholas D.E.

    2015-01-01

    Glycine decarboxylase (GLDC) acts in the glycine cleavage system to decarboxylate glycine and transfer a one-carbon unit into folate one-carbon metabolism. GLDC mutations cause a rare recessive disease non-ketotic hyperglycinemia (NKH). Mutations have also been identified in patients with neural tube defects (NTDs); however, the relationship between NKH and NTDs is unclear. We show that reduced expression of Gldc in mice suppresses glycine cleavage system activity and causes two distinct disease phenotypes. Mutant embryos develop partially penetrant NTDs while surviving mice exhibit post-natal features of NKH including glycine accumulation, early lethality and hydrocephalus. In addition to elevated glycine, Gldc disruption also results in abnormal tissue folate profiles, with depletion of one-carbon-carrying folates, as well as growth retardation and reduced cellular proliferation. Formate treatment normalizes the folate profile, restores embryonic growth and prevents NTDs, suggesting that Gldc deficiency causes NTDs through limiting supply of one-carbon units from mitochondrial folate metabolism. PMID:25736695

  1. Arrhythmia and cardiac defects are a feature of spinal muscular atrophy model mice.

    PubMed

    Heier, Christopher R; Satta, Rosalba; Lutz, Cathleen; DiDonato, Christine J

    2010-10-15

    Proximal spinal muscular atrophy (SMA) is the leading genetic cause of infant mortality. Traditionally, SMA has been described as a motor neuron disease; however, there is a growing body of evidence that arrhythmia and/or cardiomyopathy may present in SMA patients at an increased frequency. Here, we ask whether SMA model mice possess such phenotypes. We find SMA mice suffer from severe bradyarrhythmia characterized by progressive heart block and impaired ventricular depolarization. Echocardiography further confirms functional cardiac deficits in SMA mice. Additional investigations show evidence of both sympathetic innervation defects and dilated cardiomyopathy at late stages of disease. Based upon these data, we propose a model in which decreased sympathetic innervation causes autonomic imbalance. Such imbalance would be characterized by a relative increase in the level of vagal tone controlling heart rate, which is consistent with bradyarrhythmia and progressive heart block. Finally, treatment with the histone deacetylase inhibitor trichostatin A, a drug known to benefit phenotypes of SMA model mice, produces prolonged maturation of the SMA heartbeat and an increase in cardiac size. Treated mice maintain measures of motor function throughout extended survival though they ultimately reach death endpoints in association with a progression of bradyarrhythmia. These data represent the novel identification of cardiac arrhythmia as an early and progressive feature of murine SMA while providing several new, quantitative indices of mouse health. Together with clinical cases that report similar symptoms, this reveals a new area of investigation that will be important to address as we move SMA therapeutics towards clinical success.

  2. Demonstration of defect free EUV mask for 22nm NAND flash contact layer using electron beam inspection system

    NASA Astrophysics Data System (ADS)

    Shimomura, Takeya; Kawashima, Satoshi; Inazuki, Yuichi; Abe, Tsukasa; Takikawa, Tadahiko; Mohri, Hiroshi; Hayashi, Naoya; Wang, Fei; Ma, Long Eric; Zhao, Yan; Kuan, Chiyan; Xiao, Hong; Jau, Jack

    2011-04-01

    Fabrication of defect free EUV masks including their inspection is the most critical challenge for implementing EUV lithography into semiconductor high volume manufacturing (HVM) beyond 22nm half-pitch (HP) node. The contact to bit-line (CB) layers of NAND flash devices are the most likely the first lithography layers that EUV will be employed for manufacturing due to the aggressive scaling and the difficulty for making the pattern with the current ArF lithography. To assure the defect free EUV mask, we have evaluated electron beam inspection (EBI) system eXplore™ 5200 developed by Hermes Microvision, Inc. (HMI) [1]. As one knows, the main issue of EBI system is the low throughput. To solve this challenge, a function called Lightning Scan™ mode has been recently developed and installed in the system, which allows the system to only inspect the pattern areas while ignoring blanket areas, thus dramatically reduced the overhead time and enable us to inspect CB layers of NAND Flash device with much higher throughput. In this present work, we compared the Lightning scan mode with Normal scan mode on sensitivity and throughput. We found out the Lightning scan mode can improve throughput by a factor of 10 without any sacrifices of sensitivity. Furthermore, using the Lightning scan mode, we demonstrated the possibility to fabricate the defect free EUV masks with moderate inspection time.

  3. Experimental demonstration of cascaded AWG access network featuring bi-directional transmission and polarization multiplexing.

    PubMed

    Tsalamanis, Ioannis; Rochat, Etienne; Walker, Stuart; Parker, Michael; Holburn, D

    2004-03-08

    We present the first experimental demonstration of a bidirectional cascaded arrayed-waveguide grating (AWG) access network combining one NxN AWG in the central office with multiple 1xN AWG's at the distribution points, such as to individually address N(2) users with only N wavelengths. Downstream and upstream data share the same optical path. BER curves were measured using 2.5Gb/s data stream in each direction, and error free transmission achieved for downstream and upstream, with only 0.3dB power penalty for simultaneous transmission. The addition of two orthogonal polarization-multiplexed channels per wavelength doubled the number of possible end users. Error free transmission was achieved with simultaneous upstream and downstream transmission of a composite signal featuring eight 2.5Gb/s channels (2 polarizations x 4 wavelengths).

  4. Functional MRI demonstrates pain perception in hand osteoarthritis has features of central pain processing

    PubMed Central

    Sofat, Nidhi; Smee, Cori; Hermansson, Monika; Howard, Matthew; Baker, Emma H; Howe, Franklyn A; Barrick, Thomas R

    2013-01-01

    Background Hand osteoarthritis (HOA) is typified by pain and reduced function. We hypothesised that people with HOA have enhanced sensitivity and activation of peripheral nociceptors in the hand, thereby potentiating chronic pain. In our study we aimed to assess if central sensitisation mediates pain perception in osteoarthritis of the hand. Methods Participants with proximal and distal interphalangeal joint (PIP/DIP) HOA and non-OA controls were recruited. Clinical pain scores using the visual analogue scale (VAS) were recorded before and after performing a painful hand task. Central pain processing was evaluated with functional brain neuroimaging (fMRI) using a finger flexion-extension (FFE) task performed over 3 minutes. Data was analysed with FMRIB software (www.fmrib.ox.ac.uk/fsl). Group mean activation of functional MRI signal between hand osteoarthritis and control non-arthritic participants was compared. Results Our group of hand OA participants reported high pain levels compared with non-arthritic controls as demonstrated by the mean VAS in hand OA participants of 59.31± 8.19 mm compared to 4.00 ± 1.89 mm in controls (p < 0.0001), despite all participants reporting analgesic use. Functional MRI analysis showed increased activation in the thalamus, cingulate, frontal and somatosensory cortex in the hand OA group but not in controls (thresholded at p < 0.05). Regions of activation were mapped to Brodmann areas 3, 4, 6, 9, 13, 22, 24 and 44. Activated regions found in our study are recognised higher brain pain processing centres implicated in central sensitisation. Conclusions People with hand osteoarthritis demonstrated features of central sensitisation that was evident after a finger flexion-extension task using functional MRI. Functional MRI is a useful biomarker in detecting pain in hand osteoarthritis and could be used in future hand osteoarthritis pain studies to evaluate pain modulation strategies. PMID:24294351

  5. Histopathological features of bone regeneration in a canine segmental ulnar defect model

    PubMed Central

    2014-01-01

    Background Today, finding an ideal biomaterial to treat the large bone defects, delayed unions and non-unions remains a challenge for orthopaedic surgeions and researchers. Several studies have been carried out on the subject of bone regeneration, each having its own advantages. The present study has been designed in vivo to evaluate the effects of cellular auto-transplantation of tail vertebrae on healing of experimental critical bone defect in a dog model. Methods Six indigenous breeds of dog with 32 ± 3.6 kg average weight from both sexes (5 males and 1 female) received bilateral critical-sized ulnar segmental defects. After determining the health condition, divided to 2 groups: The Group I were kept as control I (n = 1) while in Group II (experimental group; n = 5) bioactive bone implants were inserted. The defects were implanted with either autogeneic coccygeal bone grafts in dogs with 3-4 cm diaphyseal defects in the ulna. Defects were stabilized with internal plate fixation, and the control defects were not stabilized. Animals were euthanized at 16 weeks and analyzed by histopathology. Results Histological evaluation of this new bone at sixteen weeks postoperatively revealed primarily lamellar bone, with the formation of new cortices and normal-appearing marrow elements. And also reformation cortical compartment and reconstitution of marrow space were observed at the graft-host interface together with graft resorption and necrosis responses. Finally, our data were consistent with the osteoconducting function of the tail autograft. Conclusions Our results suggested that the tail vertebrae autograft seemed to be a new source of autogenous cortical bone in order to supporting segmental long bone defects in dogs. Furthermore, cellular autotransplantation was found to be a successful replacement for the tail vertebrae allograft bone at 3-4 cm segmental defects in the canine mid- ulna. Clinical application using graft expanders or bone

  6. Do Linguistic Features of Science Test Items Prevent English Language Learners from Demonstrating Their Knowledge?

    ERIC Educational Resources Information Center

    Noble, Tracy; Kachchaf, Rachel; Rosebery, Ann; Warren, Beth; O'Connor, Mary Catherine; Wang, Yang

    2014-01-01

    Little research has examined individual linguistic features that influence English language learners (ELLs) test performance. Furthermore, research has yet to explore the relationship between the science strand of test items and the types of linguistic features the items include. Utilizing Differential Item Functioning, this study examines ELL…

  7. Feature extraction in MFL signals of machined defects in steel tubes

    NASA Astrophysics Data System (ADS)

    Perazzo, R.; Pignotti, A.; Reich, S.; Stickar, P.

    2001-04-01

    Thirty defects of various shapes were machined on the external and internal wall surfaces of a 177 mm diameter ferromagnetic steel pipe. MFL signals were digitized and recorded at a frequency of 4 Khz. Various magnetizing currents and relative tube-probe velocities of the order of 2m/s were used. The identification of the location of the defect by a principal component/neural network analysis of the signal is shown to be more effective than the standard procedure of classification based on the average signal frequency.

  8. The role of nanoscale defect features in enhancing the thermoelectric performance of p-type nanostructured SiGe alloys.

    PubMed

    Bathula, Sivaiah; Jayasimhadri, M; Gahtori, Bhasker; Singh, Niraj Kumar; Tyagi, Kriti; Srivastava, A K; Dhar, Ajay

    2015-08-07

    Despite SiGe being one of the most widely studied thermoelectric materials owing to its application in radioisotope thermoelectric generators (RTG), the thermoelectric figure-of merit (ZT) of p-type SiGe is still quite low, resulting in poor device efficiencies. In the present study, we report a substantial enhancement in ZT∼ 1.2 at 900 °C for p-type nanostructured Si80Ge20 alloys by creating several types of defect features within the Si80Ge20 nanostructured matrix in a spectrum of nano to meso-scale dimensions during its nanostructuring, by employing mechanical alloying followed by spark plasma sintering. This enhancement in ZT, which is ∼25% over the existing state-of-the-art value for a p-type nanostructured Si80Ge20 alloy, is primarily due to its ultralow thermal conductivity of ∼2.04 W m(-1) K(-1) at 900 °C, resulting from the scattering of low-to-high wavelength heat-carrying phonons by different types of defect features in a range of nano to meso-scale dimensions in the Si80Ge20 nanostructured matrix. These include point defects, dislocations, isolated amorphous regions, nano-scale grain boundaries and more importantly, the nano to meso-scale residual porosity distributed throughout the Si80Ge20 matrix. These nanoscale multi-dimensional defect features have been characterized by employing scanning and transmission electron microscopy and correlated with the electrical and thermal transport properties, based on which the enhancement of ZT has been discussed.

  9. A Drosophila Model of Neuronopathic Gaucher Disease Demonstrates Lysosomal-Autophagic Defects and Altered mTOR Signalling and Is Functionally Rescued by Rapamycin

    PubMed Central

    Grönke, Sebastian; Castillo-Quan, Jorge Iván; Woodling, Nathaniel S.; Li, Li; Sirka, Ernestas; Gegg, Matthew; Mills, Kevin; Hardy, John; Bjedov, Ivana

    2016-01-01

    Glucocerebrosidase (GBA1) mutations are associated with Gaucher disease (GD), an autosomal recessive disorder caused by functional deficiency of glucocerebrosidase (GBA), a lysosomal enzyme that hydrolyzes glucosylceramide to ceramide and glucose. Neuronopathic forms of GD can be associated with rapid neurological decline (Type II) or manifest as a chronic form (Type III) with a wide spectrum of neurological signs. Furthermore, there is now a well-established link between GBA1 mutations and Parkinson's disease (PD), with heterozygote mutations in GBA1 considered the commonest genetic defect in PD. Here we describe a novel Drosophila model of GD that lacks the two fly GBA1 orthologs. This knock-out model recapitulates the main features of GD at the cellular level with severe lysosomal defects and accumulation of glucosylceramide in the fly brain. We also demonstrate a block in autophagy flux in association with reduced lifespan, age-dependent locomotor deficits and accumulation of autophagy substrates in dGBA-deficient fly brains. Furthermore, mechanistic target of rapamycin (mTOR) signaling is downregulated in dGBA knock-out flies, with a concomitant upregulation of Mitf gene expression, the fly ortholog of mammalian TFEB, likely as a compensatory response to the autophagy block. Moreover, the mTOR inhibitor rapamycin is able to partially ameliorate the lifespan, locomotor, and oxidative stress phenotypes. Together, our results demonstrate that this dGBA1-deficient fly model is a useful platform for the further study of the role of lysosomal-autophagic impairment and the potential therapeutic benefits of rapamycin in neuronopathic GD. These results also have important implications for the role of autophagy and mTOR signaling in GBA1-associated PD. SIGNIFICANCE STATEMENT We developed a Drosophila model of neuronopathic GD by knocking-out the fly orthologs of the GBA1 gene, demonstrating abnormal lysosomal pathology in the fly brain. Functioning lysosomes are

  10. Feasibility demonstration of a massively parallelizable optical near-field sensor for sub-wavelength defect detection and imaging

    PubMed Central

    Mostafavi, Mahkamehossadat; Diaz, Rodolfo E.

    2016-01-01

    To detect and resolve sub-wavelength features at optical frequencies, beyond the diffraction limit, requires sensors that interact with the electromagnetic near-field of those features. Most instruments operating in this modality scan a single detector element across the surface under inspection because the scattered signals from a multiplicity of such elements would end up interfering with each other. However, an alternative massively parallelized configuration, capable of interrogating multiple adjacent areas of the surface at the same time, was proposed in 2002. Full physics simulations of the photonic antenna detector element that enables this instrument, show that using conventional red laser light (in the 600 nm range) the detector magnifies the signal from an 8 nm particle by up to 1.5 orders of magnitude. The antenna is a shaped slot element in a 60 nm silver film. The ability of this detector element to resolve λ/78 objects is confirmed experimentally at radio frequencies by fabricating an artificial material structure that mimics the optical permittivity of silver scaled to 2 GHz, and “cutting” into it the slot antenna. The experimental set-up is also used to demonstrate the imaging of a patterned surface in which the critical dimensions of the pattern are λ/22 in size. PMID:27185385

  11. Feasibility demonstration of a massively parallelizable optical near-field sensor for sub-wavelength defect detection and imaging

    NASA Astrophysics Data System (ADS)

    Mostafavi, Mahkamehossadat; Diaz, Rodolfo E.

    2016-05-01

    To detect and resolve sub-wavelength features at optical frequencies, beyond the diffraction limit, requires sensors that interact with the electromagnetic near-field of those features. Most instruments operating in this modality scan a single detector element across the surface under inspection because the scattered signals from a multiplicity of such elements would end up interfering with each other. However, an alternative massively parallelized configuration, capable of interrogating multiple adjacent areas of the surface at the same time, was proposed in 2002. Full physics simulations of the photonic antenna detector element that enables this instrument, show that using conventional red laser light (in the 600 nm range) the detector magnifies the signal from an 8 nm particle by up to 1.5 orders of magnitude. The antenna is a shaped slot element in a 60 nm silver film. The ability of this detector element to resolve λ/78 objects is confirmed experimentally at radio frequencies by fabricating an artificial material structure that mimics the optical permittivity of silver scaled to 2 GHz, and “cutting” into it the slot antenna. The experimental set-up is also used to demonstrate the imaging of a patterned surface in which the critical dimensions of the pattern are λ/22 in size.

  12. Feasibility demonstration of a massively parallelizable optical near-field sensor for sub-wavelength defect detection and imaging.

    PubMed

    Mostafavi, Mahkamehossadat; Diaz, Rodolfo E

    2016-05-17

    To detect and resolve sub-wavelength features at optical frequencies, beyond the diffraction limit, requires sensors that interact with the electromagnetic near-field of those features. Most instruments operating in this modality scan a single detector element across the surface under inspection because the scattered signals from a multiplicity of such elements would end up interfering with each other. However, an alternative massively parallelized configuration, capable of interrogating multiple adjacent areas of the surface at the same time, was proposed in 2002. Full physics simulations of the photonic antenna detector element that enables this instrument, show that using conventional red laser light (in the 600 nm range) the detector magnifies the signal from an 8 nm particle by up to 1.5 orders of magnitude. The antenna is a shaped slot element in a 60 nm silver film. The ability of this detector element to resolve λ/78 objects is confirmed experimentally at radio frequencies by fabricating an artificial material structure that mimics the optical permittivity of silver scaled to 2 GHz, and "cutting" into it the slot antenna. The experimental set-up is also used to demonstrate the imaging of a patterned surface in which the critical dimensions of the pattern are λ/22 in size.

  13. Erythroid precursors from patients with low-risk myelodysplasia demonstrate ultrastructural features of enhanced autophagy of mitochondria.

    PubMed

    Houwerzijl, E J; Pol, H-W D; Blom, N R; van der Want, J J L; de Wolf, J Th M; Vellenga, E

    2009-05-01

    Recent studies in erythroid cells have shown that autophagy is an important process for the physiological clearance of mitochondria during terminal differentiation. However, autophagy also plays an important role in removing damaged and dysfunctional mitochondria. Defective mitochondria and impaired erythroid maturation are important characteristics of low-risk myelodysplasia. In this study we therefore questioned whether the autophagic clearance of mitochondria might be altered in erythroblasts from patients with refractory anemia (RA, n=3) and RA with ringed sideroblasts (RARS, n=6). Ultrastructurally, abnormal and iron-laden mitochondria were abundant, especially in RARS patients. A large proportion (52+/-16%) of immature and mature myelodysplastic syndrome (MDS) erythroblasts contained cytoplasmic vacuoles, partly double membraned and positive for lysosomal marker LAMP-2 and mitochondrial markers, findings compatible with autophagic removal of dysfunctional mitochondria. In healthy controls only mature erythroblasts comprised these vacuoles (12+/-3%). These findings were confirmed morphometrically showing an increased vacuolar surface in MDS erythroblasts compared to controls (P<0.0001). In summary, these data indicate that MDS erythroblasts show features of enhanced autophagy at an earlier stage of erythroid differentiation than in normal controls. The enhanced autophagy might be a cell protective mechanism to remove defective iron-laden mitochondria.

  14. Specific features of the circular dichroism of a chiral photonic crystal with a defect layer inside in the presence of a gain

    NASA Astrophysics Data System (ADS)

    Gevorgyan, A. H.

    2017-01-01

    The specific features of the circular dichroism (CD) spectra of a cholesteric liquid crystal (CLC) layer with a defect layer inside in the presence of gain have been investigated. The features of the dependence of CD on the parameter characterizing the gain on the defect mode are analyzed for two cases: (i) gain is present in the defect layer and is absent in the CLC sublayers and (ii) gain is absent in the defect layer but is present in the CLC sublayers. It is shown that these dependences significantly differ in the two aforementioned cases. The dependences of the reflection, transmission, and absorption on the defect mode on the gain parameter have been investigated for incident light with both circular polarizations.

  15. Tears of the fascia cruris demonstrate characteristic sonographic features: a case series analysis

    PubMed Central

    Morton, Sarah; Chan, Otto; Webborn, Nick; Pritchard, Melanie; Morrissey, Dylan

    2015-01-01

    Summary Background fascia cruris (FC) tears have recently been recognised in the literature, although little is known about their characteristic ultrasound findings. The aim was to describe the echo-graphic features of FC tears in order to improve recognition and diagnosis. Methods the ultrasound reports and images of >600 patients attending a specialist musculoskeletal clinic for Achilles tendon ultrasound scans between October 2010–May 2014 were reviewed. Any patient diagnosed with a FC tear had a structured data set extracted. All ultrasound images were performed by one consultant radiologist. Bilateral Achilles images were available for analysis. Results sixteen patients from >600 subjects were diagnosed with a FC tear. Fourteen subjects were male and two female (mean age 37.8; range 23–61), with seven elite level sports men. Nine tears were right sided and seven left, with eight situated laterally and seven medially. Seven of the tears were situated in the musculotendinous junction. Symptomatic Achilles tendinopathy co-existed in ten of sixteen subjects (average transverse diameter of Achilles tendon = 7.1±2.0 mm). Conclusion FC tears should be considered in the differential diagnoses for Achillodynia, diagnosed using their characteristic ultrasound findings, with a hypoechoic area at the medial or lateral attachment to the Achilles tendon in the transverse plane. PMID:26958540

  16. Quantitative Sensory Testing in Painful Hand Osteoarthritis Demonstrates Features of Peripheral Sensitisation

    PubMed Central

    Wajed, Julekha; Ejindu, Vivian; Heron, Christine; Hermansson, Monika; Kiely, Patrick; Sofat, Nidhi

    2012-01-01

    Hand osteoarthritis (HOA) is a prevalent condition for which treatments are based on analgesia and physical therapies. Our primary objective was to evaluate pain perception in participants with HOA by assessing the characteristics of nodal involvement, pain threshold in each hand joint, and radiological severity. We hypothesised that inflammation in hand osteoarthritis joints enhances sensitivity and firing of peripheral nociceptors, thereby causing chronic pain. Participants with proximal and distal interphalangeal (PIP and DIP) joint HOA and non-OA controls were recruited. Clinical parameters of joint involvement were measured including clinical nodes, VAS (visual analogue score) for pain (0–100 mm scale), HAQ (health assessment questionnaire), and Kellgren-Lawrence scores for radiological severity and pain threshold measurement were performed. The mean VAS in HOA participants was 59.3 mm ± 8.19 compared with 4.0 mm ± 1.89 in the control group (P < 0.0001). Quantitative sensory testing (QST) demonstrated lower pain thresholds in DIP/PIP joints and other subgroups in the OA group including the thumb, metacarpophalangeal (MCPs), joints, and wrists (P < 0.008) but not in controls (P = 0.348). Our data demonstrate that HOA subjects are sensitised to pain due to increased firing of peripheral nociceptors. Future work to evaluate mechanisms of peripheral sensitisation warrants further investigation. PMID:23209475

  17. Innovative Structural Design Features for a 10 m Solar Sail Demonstrator

    NASA Technical Reports Server (NTRS)

    Laue, G.; Moore, J.; Clayton, W.

    2004-01-01

    The successful development of sail architectures will require careful attention to a number of key issues including but not limited to material strength issues, stress conditions for the membrane, load interactions between membrane and structure, and membrane material planarity. Along with the inherent challenges of fabricating and handling very large membrane structures these issues will pose real challenges for the near-term development of practical sail technologies. SRS has developed innovative technologies that deal directly with the challenges of developing very large sail membranes. Some of these technologies include edge reinforcements and innovative reinforcement attachment techniques, production of flight durable sail materials of less than 2.5 micron thicknesses and large scale fabrication techniques. SRS has employed these technologies in several large 10 m demonstrators that have been delivered to LaRC for solar vacuum testing. Details of the design of this system will be discussed.

  18. Feasibility Demonstration of a Massively Parallelizable Near-Field Sensor for Sub-Wavelength Defect Detection and Imaging

    NASA Astrophysics Data System (ADS)

    Mostafavi, Mahkamehossadat

    To detect and resolve sub-wavelength features at optical frequencies, beyond the diffraction limit, requires sensors that interact with the electromagnetic near-field of those features. Most instruments operating in this modality scan a single detector element across the surface under inspection because the scattered signals from a multiplicity of such elements would end up interfering with each other. However, an alternative massively parallelized configuration, consisting of a remotely interrogating array of dipoles, capable of interrogating multiple adjacent areas of the surface at the same time, was proposed in 2002. In the present work a remotely interrogating slot antenna inside a 60nm silver slab is designed which increases the signal to noise ratio of the original system. The antenna is tuned to resonance at 600nm range by taking advantage of the plasmon resonance properties of the metal's negative permittivity and judicious shaping of the slot element. Full-physics simulations show the capability of detecting an 8nm particle using red light illumination. The sensitivity to the lambda/78 particle is attained by detecting the change induced on the antenna's far field signature by the proximate particle, a change that is 15dB greater than the scattering signature of the particle by itself. To verify the capabilities of this technology in a readily accessible experimental environment, a radiofrequency scale model is designed using a meta-material to mimic the optical properties of silver in the 2GHz to 5GHz range. Various approaches to the replication of the metal's behavior are explored in a trade-off between fidelity to the metal's natural plasmon response, desired bandwidth of the demonstration, and ii manufacturability of the meta-material. The simulation and experimental results successfully verify the capability of the proposed near-field sensor in sub-wavelength detection and imaging not only as a proof of concept for optical frequencies but also as a

  19. Graphene-augmented nanofiber scaffolds demonstrate new features in cells behaviour

    NASA Astrophysics Data System (ADS)

    Kazantseva, Jekaterina; Ivanov, Roman; Gasik, Michael; Neuman, Toomas; Hussainova, Irina

    2016-07-01

    Three-dimensional (3D) customized scaffolds capable to mimic a native extracellular matrix open new frontiers in cells manipulation and advanced therapy. The major challenge is in a proper substrate for in vitro models on engineered scaffolds, capable to modulate cells differentiation. Here for the first time we demonstrate novel design and functionality of the 3D porous scaffolds of aligned, self-assembled ceramic nanofibers of ultra-high anisotropy ratio (~107), augmented into graphene shells. This unique hybrid nano-network allows an exceptional combination of selective guidance stimuli of stem cells differentiation, immune reactions variations, and local immobilization of cancer cells, which was not available before. The scaffolds were shown to be able to direct human mesenchymal stem cells (important for stimulation of neuronal and muscle cells) preferential orientation, to suppress major inflammatory factors, and to localize cancer cells; all without additions of specific culture media. The selective downregulation of specific cytokines is anticipated as a new tool for understanding of human immune system and ways of treatment of associated diseases. The effects observed are self-regulated by cells only, without side effects, usually arising from use of external factors. New scaffolds may open new horizons for stem cells fate control such as towards axons and neurites regeneration (Alzheimer’s disease) as well as cancer therapy development.

  20. Graphene-augmented nanofiber scaffolds demonstrate new features in cells behaviour

    PubMed Central

    Kazantseva, Jekaterina; Ivanov, Roman; Gasik, Michael; Neuman, Toomas; Hussainova, Irina

    2016-01-01

    Three-dimensional (3D) customized scaffolds capable to mimic a native extracellular matrix open new frontiers in cells manipulation and advanced therapy. The major challenge is in a proper substrate for in vitro models on engineered scaffolds, capable to modulate cells differentiation. Here for the first time we demonstrate novel design and functionality of the 3D porous scaffolds of aligned, self-assembled ceramic nanofibers of ultra-high anisotropy ratio (~107), augmented into graphene shells. This unique hybrid nano-network allows an exceptional combination of selective guidance stimuli of stem cells differentiation, immune reactions variations, and local immobilization of cancer cells, which was not available before. The scaffolds were shown to be able to direct human mesenchymal stem cells (important for stimulation of neuronal and muscle cells) preferential orientation, to suppress major inflammatory factors, and to localize cancer cells; all without additions of specific culture media. The selective downregulation of specific cytokines is anticipated as a new tool for understanding of human immune system and ways of treatment of associated diseases. The effects observed are self-regulated by cells only, without side effects, usually arising from use of external factors. New scaffolds may open new horizons for stem cells fate control such as towards axons and neurites regeneration (Alzheimer’s disease) as well as cancer therapy development. PMID:27443974

  1. Virtual reconstruction of very large skull defects featuring partly and completely missing midsagittal planes.

    PubMed

    Senck, Sascha; Coquerelle, Michael; Weber, Gerhard W; Benazzi, Stefano

    2013-05-01

    Despite the development of computer-based methods, cranial reconstruction of very large skull defects remains a challenge particularly if the damage affects the midsagittal region hampering the usage of mirror imaging techniques. This pilot study aims to deliver a new method that goes beyond mirror imaging, giving the possibility to reconstruct crania characterized by large missing areas, which might be useful in the fields of paleoanthropology, bioarcheology, and forensics. We test the accuracy of digital reconstructions in cases where two-thirds or more of a human cranium were missing. A three-dimensional (3D) virtual model of a human cranium was virtually damaged twice to compare two destruction-reconstruction scenarios. In the first case, a small fraction of the midsagittal region was still preserved, allowing the application of mirror imaging techniques. In the second case, the damage affected the complete midsagittal region, which demands a new approach to estimate the position of the midsagittal plane. Reconstructions were carried out using CT scans from a sample of modern humans (12 males and 13 females), to which 3D digital modeling techniques and geometric morphometric methods were applied. As expected, the second simulation showed a larger variability than the first one, which underlines the fact that the individual midsagittal plane is of course preferable in order to minimize the reconstruction error. However, in both simulations the Procrustes mean shape was an effective reference for the reconstruction of the entire cranium, producing models that showed a remarkably low error of about 3 mm, given the extent of missing data.

  2. Discriminant Analysis of Defective and Non-Defective Field Pea (Pisum sativum L.) into Broad Market Grades Based on Digital Image Features.

    PubMed

    McDonald, Linda S; Panozzo, Joseph F; Salisbury, Phillip A; Ford, Rebecca

    2016-01-01

    Field peas (Pisum sativum L.) are generally traded based on seed appearance, which subjectively defines broad market-grades. In this study, we developed an objective Linear Discriminant Analysis (LDA) model to classify market grades of field peas based on seed colour, shape and size traits extracted from digital images. Seeds were imaged in a high-throughput system consisting of a camera and laser positioned over a conveyor belt. Six colour intensity digital images were captured (under 405, 470, 530, 590, 660 and 850nm light) for each seed, and surface height was measured at each pixel by laser. Colour, shape and size traits were compiled across all seed in each sample to determine the median trait values. Defective and non-defective seed samples were used to calibrate and validate the model. Colour components were sufficient to correctly classify all non-defective seed samples into correct market grades. Defective samples required a combination of colour, shape and size traits to achieve 87% and 77% accuracy in market grade classification of calibration and validation sample-sets respectively. Following these results, we used the same colour, shape and size traits to develop an LDA model which correctly classified over 97% of all validation samples as defective or non-defective.

  3. Non-Invasive Imaging Demonstrates Clinical Features of Ankylosing Spondylitis in a Rat Adjuvant Model: a Case Study

    PubMed Central

    Dawson, J.; Kolbinger, F.; Kramer, I.; Beckmann, N.

    2016-01-01

    Main features of ankylosing spondylitis like inflammatory erosive osteopenia and bony overgrowth are recapitulated in rats challenged with complete Freund’s adjuvant. In vivo changes induced in the rat spine were followed longitudinally by magnetic resonance imaging (MRI) and assessed terminally by micro-computerized tomography (micro-CT) and histology. Signals reflecting inflammation were detected by MRI at levels L5-L6 throughout the experiment, peaking at day 27 after adjuvant. Bone erosion and formation occurred from this time point onward, as confirmed by micro-CT. Histology confirmed the inflammation and bone remodeling. The present study demonstrates the potential of imaging for longitudinal assessments of spinal changes in this animal model and the excellent correlation between in vivo images and histology underlines its fundamental role in the validation of non-invasive imaging. PMID:28076929

  4. Field Demonstration of Electro-Scan Defect Location Technology for Condition Assessment of Wastewater Collection Systems - Paper

    EPA Science Inventory

    A USEPA-sponsored field demonstration program was conducted to gather technically reliable cost and performance information on the electro-scan (FELL -41) pipeline condition assessment technology. Electro-scan technology can be used to estimate the magnitude and location of pote...

  5. Demonstration of a wavelength monitor comprised of racetrack-ring resonators with defect mediated photodiodes operating in the C-band.

    PubMed

    Dey, Rajat; Doylend, Jonathan; Ackert, Jason; Evans, Andrew; Jessop, Paul; Knights, Andrew

    2013-10-07

    A CMOS compatible wavelength monitor comprised of two thermally tuned racetrack-ring resonators with defect mediated photodiode structures is experimentally demonstrated in monolithic silicon. Each resonator is independently tuned so as to determine an unknown input wavelength by tuning the resonance peak locations until there is overlap between the two comb spectra. The presence of two of these resonator/heater components, each with a different free spectral range, increases the unambiguous measurement range when compared to one component used on its own.

  6. Demonstration of defective C3-receptor-mediated clearance by the reticuloendothelial system in patients with acquired immunodeficiency syndrome.

    PubMed Central

    Bender, B S; Bohnsack, J F; Sourlis, S H; Frank, M M; Quinn, T C

    1987-01-01

    The function of macrophage C3 receptors was assessed in vivo by measuring the clearance of C3-sensitized autologous erythrocytes in seven acquired immunodeficiency syndrome (AIDS) patients, eight healthy homosexual men, eight healthy heterosexual men, and four infected controls. Healthy heterosexual men had an initial clearance of 50.1 +/- 2.0% of the inoculum, with a release of a small portion of these cells (10.9 +/- 1.3%) into the circulation. Healthy homosexual men had a greater initial clearance of 66.0 +/- 4.2% (P less than 0.01) followed by a similar release (14.0 +/- 3.3%). AIDS patients had an initial clearance of 60.6 +/- 7.5% but had a relatively large release of cells (25.6 +/- 3.2%) (P less than 0.005 vs. heterosexuals; P less than 0.05 vs. homosexuals), suggesting a failure of macrophage phagocytosis. Infected controls had an initial clearance of 59.4 +/- 4.9%, with a release of 19.6 +/- 3.8% (P = NS vs. AIDS). These data, in addition to Fc-receptor dysfunction, demonstrate a global reticuloendothelial system dysfunction in AIDS patients. This may contribute to their frequent infections with opportunistic pathogens and inappropriate immune responses against these microorganisms. Images PMID:3546375

  7. Placental C4d deposition is a feature of defective placentation: observations in cases of preeclampsia and miscarriage.

    PubMed

    Kim, Eun Na; Yoon, Bo Hyun; Lee, Joong Yeup; Hwang, Doyeong; Kim, Ki Chul; Lee, JoonHo; Shim, Jae-Yoon; Kim, Chong Jai

    2015-06-01

    Placental C4d deposition is frequent in preeclampsia, and shallow placentation is a characteristic of both preeclampsia and miscarriage. This study was conducted to determine the relationship among placental C4d, maternal human leukocyte antigen (HLA) antibodies, and placental pathology in preeclampsia and miscarriage cases. The patient population (N = 104) included those with (1) preterm preeclampsia with fetal growth restriction (PE-FGR; n = 21), (2) preterm preeclampsia (PE; n = 20), (3) spontaneous preterm delivery (sPTD; n = 39), and (4) miscarriage (n = 24). C4d immunohistochemistry was performed, and the presence of maternal plasma HLA antibodies was examined. C4d staining of the syncytiotrophoblast was more frequent in PE-FGR patients (76.2 %) than in PE (10.0 %; p < 0.001) and sPTD (2.6 %; p < 0.001) patients. Maternal HLA antibody-positive rate was not different among the study groups. There was a significant correlation between C4d immunoreactivity and placental pathology consistent with maternal vascular underperfusion (p < 0.001) but not with maternal HLA antibody status. In miscarriages, the positive rates of C4d, HLA class I, and HLA class II antibodies were 58.3, 25.0, and 12.5 %, respectively. There was no correlation between the presence of maternal HLA class I or II antibodies and placental C4d immunoreactivity. This study confirms frequent placental C4d deposition in preeclampsia with fetal growth restriction and miscarriage. The association between placental C4d deposition and pathological findings of maternal vascular underperfusion suggests that C4d staining of the syncytiotrophoblast is a consequence of defective placentation rather than of a specific maternal immune response against fetal HLA. The study also demonstrates the usefulness of C4d as a biomarker of placentas at risk.

  8. Order and defectivity nanometrology by image processing and analysis of sub-20 nm BCPs features for lithographic applications

    NASA Astrophysics Data System (ADS)

    Simão, C.; Tuchapsky, D.; Khunsin, W.; Amann, A.; Morris, M. A.; Sotomayor Torres, Clivia

    2014-05-01

    The line patterns obtained by the self-assembly of the block copolymer (BCP) polystyrene-b-polyethylene oxide (PS-b-PEO) was investigated. The hexagonal PS-b-PEO 42k-11.5k in a thin film was solvent annealed in a chlorophorm saturated atmosphere for three different annealing times. The microphase segregation of this BCP returned 18nm cylinders of PEO through the PS matrix, with an approximately 40 n periodicity, as expected. Under chlorophorm vapours, the PEO cylinders oriented perpendicular to the silicon substrate while increasing the annealing time. These cylinders formed linear patterns with different alignment. To achieve insights about the percentage of alignment, defect type pareto and density, and order quantification to compare the three annealing recipes, the samples were analysed with innovative image analysis software specifically developed in our laboratory to identify elements and defects of line arrays from block copolymer self-assembly. From this technique, it was extracted dimensional metrology estimating pitch size and placement error, and the line-width of the lines was estimated. Secondly, the methodology allows identification and quantification of typical defects observable in BCP systems, such as turning points, disclination or branching points, break or lone points and end points. The defect density and the quantification of the alignment were estimated using our technique. The methodology presented here represents a step forward in dimensional metrology and defect analysis of BCP DSA systems and can be readily used to analyze other lithographic or non-lithographic patterns.

  9. A human imprinting centre demonstrates conserved acquisition but diverged maintenance of imprinting in a mouse model for Angelman syndrome imprinting defects.

    PubMed

    Johnstone, Karen A; DuBose, Amanda J; Futtner, Christopher R; Elmore, Michael D; Brannan, Camilynn I; Resnick, James L

    2006-02-01

    Prader-Willi syndrome (PWS) and Angelman syndrome (AS) are caused by the loss of imprinted gene expression from chromosome 15q11-q13. Imprinted gene expression in the region is regulated by a bipartite imprinting centre (IC), comprising the PWS-IC and the AS-IC. The PWS-IC is a positive regulatory element required for bidirectional activation of a number of paternally expressed genes. The function of the AS-IC appears to be to suppress PWS-IC function on the maternal chromosome through a methylation imprint acquired during female gametogenesis. Here we have placed the entire mouse locus under the control of a human PWS-IC by targeted replacement of the mouse PWS-IC with the equivalent human region. Paternal inheritance of the human PWS-IC demonstrates for the first time that a positive regulatory element in the PWS-IC has diverged. These mice show postnatal lethality and growth deficiency, phenotypes not previously attributed directly to the affected genes. Following maternal inheritance, the human PWS-IC is able to acquire a methylation imprint in mouse oocytes, suggesting that acquisition of the methylation imprint is conserved. However, the imprint is lost in somatic cells, showing that maintenance has diverged. This maternal imprinting defect results in expression of maternal Ube3a-as and repression of Ube3a in cis, providing evidence that Ube3a is regulated by its antisense and creating the first reported mouse model for AS imprinting defects.

  10. Demonstration of thermal control, microstructure control, defect mitigation and process parameter database generation for Ti-6Al-4V Direct Digital Manufacturing - Understanding defect mitigation and process parameter database generation for direct digital manufacturing

    SciTech Connect

    Dehoff, Ryan R.; Sridharan, Niyanth; Dinwiddie, Ralph; Robson, Alan; Jordan, Brian; Chaudhary, Anil; Babu, Sudarsanam Suresh

    2015-09-01

    Researchers from Manufacturing Demonstration Facility (MDF) at Oak Ridge National Laboratory (ORNL) worked with Applied Optimization (AO) to understand and evaluate the propensity for defect formation in builds manufactured using DM3D-POM laser direct metal deposition. The main aim of this collaboration was to understand the character of powder jet behavior as a function of the nozzle parameters such as cover gas, carrier gas, and shaping gas. In order to evaluate the sensitivities of the parameters used in model, various experiments were performed with in-situ monitoring of the powder stream characteristics using a high speed camera. A wide variety of conditions while keeping the hopper motor rpm constant, including laser power and travel speed were explored. The cross sections of the deposits were characterized using optical microscopy.

  11. Strip-Pattern-Spheres Self-Assembled from Polypeptide-Based Polymer Mixtures: Structure and Defect Features

    NASA Astrophysics Data System (ADS)

    Zhu, Xingyu; Guan, Zhou; Lin, Jiaping; Cai, Chunhua

    2016-07-01

    We found that poly(γ-benzyl-L-glutamate)-block-poly(ethylene glycol) (PBLG-b-PEG) rod-coil block copolymers and polystyrene (PS) homopolymers can cooperatively self-assemble into nano-spheres with striped patterns on their surfaces (strip-pattern-spheres) in aqueous solution. With assistance of dissipative particle dynamics simulation, it is discovered that the PS homopolymers form a spherical template core and the PBLG-b-PEG block copolymers assemble into striped patterns on the spherical surface. The hydrophobic PBLG rods are packed orderly in the strips, while the hydrophilic PEG blocks stabilize the strip-pattern-spheres in solution. Defects such as dislocations and disclinations can be observed in the striped patterns. Self-assembling temperature and sphere radius are found to affect defect densities in the striped patterns. A possible mechanism is proposed to illustrate how PBLG-b-PEG and PS cooperatively self-assemble into hierarchical spheres with striped patterns on surfaces.

  12. Omphalocele, exstrophy of cloaca, imperforate anus and spinal defect (OEIS Complex) with overlapping features of body stalk anomaly (limb body wall complex)

    PubMed Central

    Mandrekar, Suresh R. S.; Amoncar, Sangeeta; Banaulikar, Siddhartha; Sawant, Vishal; Pinto, R. G. W.

    2014-01-01

    OEIS is an extremely rare constellation of malformations, which includes omphalocele, exstrophy of cloaca, imperforate anus, and spinal defect. We report here autopsy findings in a case of OEIS complex, which apart from the major anomalies of the complex had bilateral club foot that is, congenital talipes equinovarus, right hydroureter, and body stalk anomaly. The umbilical cord was absent, and the umbilical vessels were embedded in an amniotic sheet, which connected the skin margin of the anterior body wall defect to the placenta, this feature being the hallmark of limb body wall complex (LBWC). This case further supports the view that OEIS and LBWC represent a continuous spectrum of abnormalities rather than separate conditions and may share a common etiology and pathogenetic mechanism as proposed by some authors. PMID:25400352

  13. Specific features of the spectral properties of a photonic crystal with a nanocomposite defect with allowance for the size effects

    NASA Astrophysics Data System (ADS)

    Vetrov, S. Ya.; Pankin, P. S.; Timofeev, I. V.

    2015-07-01

    The spectral properties of a one-dimensional photonic crystal (PC) with a structure defect (a layer of isotropic nanocomposite inserted between two multilayer dielectric mirrors) have been investigated. The nanocomposite consists of spherical gold nanoparticles dispersed in a transparent matrix; it is characterized by effective resonant permittivity. The dependence of the transmission and absorption spectra on the size and concentration of nanoparticles is analyzed. It is shown that the transmission spectrum contains, along with the band gap caused by Bragg diffraction of light, an additional nontransmission band due to the nanocomposite absorption near the resonant frequency.

  14. A study of the preparation of epitaxy-ready polished surfaces of (100) Gallium Antimonide substrates demonstrating ultra-low surface defects for MBE growth

    NASA Astrophysics Data System (ADS)

    Martinez, Rebecca; Tybjerg, Marius; Flint, Patrick; Fastenau, Joel; Lubyshev, Dmitri; Liu, Amy W. K.; Furlong, Mark J.

    2016-05-01

    Gallium Antimonide (GaSb) is an important Group III-V compound semiconductor which is suitable for use in the manufacture of a wide variety of optoelectronic devices such as infra-red (IR) focal plane detectors. A significant issue for the commercialisation of these products is the production of epitaxy ready GaSb, which remains a challenge for the substrate manufacturer, as the stringent demands of the MBE process, requires a high quality starting wafer. In this work large diameter GaSb crystals were grown by the Czochralski (Cz) method and wafers prepared for chemo-mechanical polishing (CMP). Innovative epi-ready treatments and novel post polish cleaning methodologies were applied. The effect of these modified finishing chemistries on substrate surface quality and the performance of epitaxially grown MBE GaSb IR detector structures were investigated. Improvements in the lowering of surface defectivity, maintaining of the surface roughness and optimisation of all flatness parameters is confirmed both pre and post MBE growth. In this paper we also discuss the influence of bulk GaSb quality on substrate surface performance through the characterisation of epitaxial structures grown on near zero etch pit density (EPD) crystals. In summary progression and development of current substrate polishing techniques has been demonstrated to deliver a consistent improved surface on GaSb wafers with a readily desorbed oxide for epitaxial growth.

  15. Pituitary and ovarian abnormalities demonstrated by CT and ultrasound in children with features of the McCune-Albright syndrome

    SciTech Connect

    Rieth, K.G.; Comite, F.; Shawker, T.H.; Cutler, G.B. Jr.

    1984-11-01

    In a random series of 97 children referred to the National Institutes of Health with a presumptive diagnosis of precocious puberty, eight girls were found to have features of the McCune-Albright syndrome, including fibrous dysplasia of bone and/or skin lesions resembling cafe au lait spots. Radiographic evaluation of these patients included computed tomography of the head and pelvic ultrasound. The pituitary glands were suspicious for abnormality in five of the eight girls. Seven girls underwent pelvic ultrasound, and in all of them the ovaries were considered to be abnormal for their chronological age; in addition, two had functional ovarian cysts. The role of diagnostic radiological studies in the diagnosis of this syndrome is discussed.

  16. Design and operating features of the high-level waste vitrification system for the West Valley demonstration project

    SciTech Connect

    Siemens, D.H.; Beary, M.M.; Barnes, S.M.; Berger, D.N.; Brouns, R.A.; Chapman, C.C.; Jones, R.M.; Peters, R.D.; Peterson, M.E.

    1986-03-01

    A liquid-fed joule-heated ceramic melter system is the reference process for immobilization of the high-level liquid waste in the US and several foreign countries. This system has been under development for over ten years at Pacific Northwest Laboratory and other national laboratories operated for the US Department of Energy. Pacific Northwest Laboratory contributed to this research through its Nuclear Waste Treatment Program and used applicable data to design and test melters and related systems using remote handling of simulated radioactive wastes. This report describes the equipment designed in support of the high-level waste vitrification program at West Valley, New York. Pacific Northwest Laboratory worked closely with West Valley Nuclear Services Company to design a liquid-fed ceramic melter, a liquid waste preparation and feed tank and pump, an off-gas treatment scrubber, and an enclosed turntable for positioning the waste canisters. Details of these designs are presented including the rationale for the design features and the alternatives considered.

  17. Rational defect introduction in silicon nanowires.

    PubMed

    Shin, Naechul; Chi, Miaofang; Howe, Jane Y; Filler, Michael A

    2013-05-08

    The controlled introduction of planar defects, particularly twin boundaries and stacking faults, in group IV nanowires remains challenging despite the prevalence of these structural features in other nanowire systems (e.g., II-VI and III-V). Here we demonstrate how user-programmable changes to precursor pressure and growth temperature can rationally generate both transverse twin boundaries and angled stacking faults during the growth of <111> oriented Si nanowires. We leverage this new capability to demonstrate prototype defect superstructures. These findings yield important insight into the mechanism of defect generation in semiconductor nanowires and suggest new routes to engineer the properties of this ubiquitous semiconductor.

  18. Interstitial deletion of 14q24.3-q32.2 in a male patient with plagiocephaly, BPES features, developmental delay, and congenital heart defects.

    PubMed

    Cingöz, Sultan; Bache, Iben; Bjerglund, Lise; Ropers, Hans-Hilger; Tommerup, Niels; Jensen, Hanne; Brøndum-Nielsen, Karen; Tümer, Zeynep

    2011-01-01

    Distal interstitial deletions of chromosome 14 involving the 14q24-q23.2 region are rare, and only been reported so far in 20 patients. Ten of these patients were analyzed both clinically and genetically. Here we present a de novo interstitial deletion of chromosome 14q24.3-q32.2 in a male patient with developmental delay, language impairment, plagiocephaly, BPES features (blepharophimosis, ptosis, epicanthus), and congenital heart defect. The deletion breakpoints were fine mapped using fluorescence in situ hybridization (FISH) and the size of the deletion is estimated to be approximately 23 Mb. Based on genotype-phenotype comparisons of the 10 previously published patients and the present case, we suggest that the shortest regions for deletion overlap may include candidate genes for speech impairment, mental retardation, and hypotonia.

  19. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L.

    1982-01-01

    Two demonstrations are described: (1) a sunset effect using a gooseneck lamp and 20 sheets of paper and (2) the preparation and determination of structural features of dimethyl sulfoxide (DMSO) by infrared spectroscopy. (SK)

  20. Replacement of amino acid sequence features of a- and c-subunits of ATP synthases of Alkaliphilic Bacillus with the Bacillus consensus sequence results in defective oxidative phosphorylation and non-fermentative growth at pH 10.5.

    PubMed

    Wang, ZhenXiong; Hicks, David B; Guffanti, Arthur A; Baldwin, Katisha; Krulwich, Terry Ann

    2004-06-18

    Mitchell's (Mitchell, P. (1961) Nature 191, 144-148) chemiosmotic model of energy coupling posits a bulk electrochemical proton gradient (Deltap) as the sole driving force for proton-coupled ATP synthesis via oxidative phosphorylation (OXPHOS) and for other bioenergetic work. Two properties of proton-coupled OXPHOS by alkaliphilic Bacillus species pose a challenge to this tenet: robust ATP synthesis at pH 10.5 that does not correlate with the magnitude of the Deltap and the failure of artificially imposed potentials to substitute for respiration-generated potentials in energizing ATP synthesis at high pH (Krulwich, T. (1995) Mol. Microbiol. 15, 403-410). Here we show that these properties, in alkaliphilic Bacillus pseudofirmus OF4, depend upon alkaliphile-specific features in the proton pathway through the a- and c-subunits of ATP synthase. Site-directed changes were made in six such features to the corresponding sequence in Bacillus megaterium, which reflects the consensus sequence for non-alkaliphilic Bacillus. Five of the six single mutants assembled an active ATPase/ATP synthase, and four of these mutants exhibited a specific defect in non-fermentative growth at high pH. Most of these mutants lost the ability to generate the high phosphorylation potentials at low bulk Deltap that are characteristic of alkaliphiles. The aLys(180) and aGly(212) residues that are predicted to be in the proton uptake pathway of the a-subunit were specifically implicated in pH-dependent restriction of proton flux through the ATP synthase to and from the bulk phase. The evidence included greatly enhanced ATP synthesis in response to an artificially imposed potential at high pH. The findings demonstrate that the ATP synthase of extreme alkaliphiles has special features that are required for non-fermentative growth and OXPHOS at high pH.

  1. Experimental demonstration of single electron transistors featuring SiO{sub 2} plasma-enhanced atomic layer deposition in Ni-SiO{sub 2}-Ni tunnel junctions

    SciTech Connect

    Karbasian, Golnaz McConnell, Michael S.; Orlov, Alexei O.; Rouvimov, Sergei; Snider, Gregory L.

    2016-01-15

    The authors report the use of plasma-enhanced atomic layer deposition (PEALD) to fabricate single-electron transistors (SETs) featuring ultrathin (≈1 nm) tunnel-transparent SiO{sub 2} in Ni-SiO{sub 2}-Ni tunnel junctions. They show that, as a result of the O{sub 2} plasma steps in PEALD of SiO{sub 2}, the top surface of the underlying Ni electrode is oxidized. Additionally, the bottom surface of the upper Ni layer is also oxidized where it is in contact with the deposited SiO{sub 2}, most likely as a result of oxygen-containing species on the surface of the SiO{sub 2}. Due to the presence of these surface parasitic layers of NiO, which exhibit features typical of thermally activated transport, the resistance of Ni-SiO{sub 2}-Ni tunnel junctions is drastically increased. Moreover, the transport mechanism is changed from quantum tunneling through the dielectric barrier to one consistent with thermally activated resistors in series with tunnel junctions. The reduction of NiO to Ni is therefore required to restore the metal-insulator-metal (MIM) structure of the junctions. Rapid thermal annealing in a forming gas ambient at elevated temperatures is presented as a technique to reduce both parasitic oxide layers. This method is of great interest for devices that rely on MIM tunnel junctions with ultrathin barriers. Using this technique, the authors successfully fabricated MIM SETs with minimal trace of parasitic NiO component. They demonstrate that the properties of the tunnel barrier in nanoscale tunnel junctions (with <10{sup −15} m{sup 2} in area) can be evaluated by electrical characterization of SETs.

  2. Expression of Dominant-Negative Thyroid Hormone Receptor Alpha1 in Leydig and Sertoli Cells Demonstrates No Additional Defect Compared with Expression in Sertoli Cells Only

    PubMed Central

    Fumel, Betty; Froment, Pascal; Holzenberger, Martin; Livera, Gabriel; Monget, Philippe; Fouchécourt, Sophie

    2015-01-01

    Background In the testis, thyroid hormone (T3) regulates the number of gametes produced through its action on Sertoli cell proliferation. However, the role of T3 in the regulation of steroidogenesis is still controversial. Methods The TRαAMI knock-in allele allows the generation of transgenic mice expressing a dominant-negative TRα1 (thyroid receptor α1) isoform restricted to specific target cells after Cre-loxP recombination. Here, we introduced this mutant allele in both Sertoli and Leydig cells using a novel aromatase-iCre (ARO-iCre) line that expresses Cre recombinase under control of the human Cyp19(IIa)/aromatase promoter. Findings We showed that loxP recombination induced by this ARO-iCre is restricted to male and female gonads, and is effective in Sertoli and Leydig cells, but not in germ cells. We compared this model with the previous introduction of TRαAMI specifically in Sertoli cells in order to investigate T3 regulation of steroidogenesis. We demonstrated that TRαAMI-ARO males exhibited increased testis weight, increased sperm reserve in adulthood correlated to an increased proliferative index at P3 in vivo, and a loss of T3-response in vitro. Nevertheless, TRαAMI-ARO males showed normal fertility. This phenotype is similar to TRαAMI-SC males. Importantly, plasma testosterone and luteinizing hormone levels, as well as mRNA levels of steroidogenesis enzymes StAR, Cyp11a1 and Cyp17a1 were not affected in TRαAMI-ARO. Conclusions/Significance We concluded that the presence of a mutant TRαAMI allele in both Leydig and Sertoli cells does not accentuate the phenotype in comparison with its presence in Sertoli cells only. This suggests that direct T3 regulation of steroidogenesis through TRα1 is moderate in Leydig cells, and that Sertoli cells are the main target of T3 action in the testis. PMID:25793522

  3. Molecular Delineation of Partial Trisomy 14q and Partial Trisomy 12p in a Patient with Dysmorphic Features, Heart Defect and Developmental Delay.

    PubMed

    Bose, Divya; Krishnamurthy, Venkatesh; Venkatesh, K S; Aiyaz, Mohamed; Shetty, Mitesh; Rao, Sudha N; Kutty, A V M

    2015-01-01

    This study describes a molecular analysis of partial trisomy 14q and partial trisomy 12p in a 5-year-old male child presenting with dysmorphic features, congenital heart disease and global developmental delay. Chromosomal analysis of the patient with GTG bands revealed a 47,XY,+der(14)t(12;14)(p13;q22)mat karyotype; the mother's karyotype was 46,XX,t(12;14)(p13;q22). Further, oligonucleotide array- CGH studies revealed an amplification of 32.3 Mb in the 14q11.1q22.1 region, substantiating partial trisomy 14q and additionally displaying an amplification of ∼1 Mb in the 12p13.3pter region for partial trisomy 12p. This is the first study to demonstrate a novel association of partial trisomies of 14q and 12p due to a 3:1 segregation of a maternal balanced translocation involving chromosomes 12 and 14. Gene ontology studies indicated 5 potential candidate genes in the amplified regions for the observed congenital anomalies.

  4. Birth Defects

    MedlinePlus

    ... how the body looks, works or both. Some birth defects like cleft lip or neural tube defects are structural problems that can be easy to see. To find others, like heart defects, doctors use special tests. Birth defects can vary from mild to severe. Some ...

  5. Polydispersity-driven topological defects as order-restoring excitations.

    PubMed

    Yao, Zhenwei; Olvera de la Cruz, Monica

    2014-04-08

    The engineering of defects in crystalline matter has been extensively exploited to modify the mechanical and electrical properties of many materials. Recent experiments on manipulating extended defects in graphene, for example, show that defects direct the flow of electric charges. The fascinating possibilities offered by defects in two dimensions, known as topological defects, to control material properties provide great motivation to perform fundamental investigations to uncover their role in various systems. Previous studies mostly focus on topological defects in 2D crystals on curved surfaces. On flat geometries, topological defects can be introduced via density inhomogeneities. We investigate here topological defects due to size polydispersity on flat surfaces. Size polydispersity is usually an inevitable feature of a large variety of systems. In this work, simulations show well-organized induced topological defects around an impurity particle of a wrong size. These patterns are not found in systems of identical particles. Our work demonstrates that in polydispersed systems topological defects play the role of restoring order. The simulations show a perfect hexagonal lattice beyond a small defective region around the impurity particle. Elasticity theory has demonstrated an analogy between the elementary topological defects named disclinations to electric charges by associating a charge to a disclination, whose sign depends on the number of its nearest neighbors. Size polydispersity is shown numerically here to be an essential ingredient to understand short-range attractions between like-charge disclinations. Our study suggests that size polydispersity has a promising potential to engineer defects in various systems including nanoparticles and colloidal crystals.

  6. A physics-based defects model and inspection algorithm for automatic visual inspection

    NASA Astrophysics Data System (ADS)

    Xie, Yu; Ye, Yutang; Zhang, Jing; Liu, Li; Liu, Lin

    2014-01-01

    The representation of physical characteristics is the most essential feature of mathematical models used for the detection of defects in automatic inspection systems. However, the feature of defects and formation of the defect image are not considered enough in traditional algorithms. This paper presents a mathematical model for defect inspection, denoted as the localized defects image model (LDIM), is different because it modeling the features of manual inspection, using a local defect merit function to quantify the cost that a pixel is defective. This function comprises two components: color deviation and color fluctuation. Parameters related to statistical data of the background region of images are also taken into consideration. Test results demonstrate that the model matches the definition of defects, as defined by international industrial standards IPC-A-610D and IPC-A-600G. Furthermore, the proposed approach enhances small defects to improve detection rates. Evaluation using a defects images database returned a 100% defect inspection rate with 0% false detection. Proving that this method could be practically applied in manufacture to quantify inspection standards and minimize false alarms resulting from human error.

  7. TU-A-12A-04: Quantitative Texture Features Calculated in Lung Tissue From CT Scans Demonstrate Consistency Between Two Databases From Different Institutions

    SciTech Connect

    Cunliffe, A; Armato, S; Castillo, R; Pham, N; Guerrero, T; Al-Hallaq, H

    2014-06-15

    Purpose: To evaluate the consistency of computed tomography (CT) scan texture features, previously identified as stable in a healthy patient cohort, in esophageal cancer patient CT scans. Methods: 116 patients receiving radiation therapy (median dose: 50.4Gy) for esophageal cancer were retrospectively identified. For each patient, diagnostic-quality pre-therapy (0-183 days) and post-therapy (5-120 days) scans (mean voxel size: 0.8mm×0.8mm×2.5mm) and a treatment planning scan and associated dose map were collected. An average of 501 32x32-pixel ROIs were placed randomly in the lungs of each pre-therapy scan. ROI centers were mapped to corresponding locations in post-therapy and planning scans using the displacement vector field output by demons deformable registration. Only ROIs with mean dose <5Gy were analyzed, as these were expected to contain minimal post-treatment damage. 140 texture features were calculated in pre-therapy and post-therapy scan ROIs and compared using Bland-Altman analysis. For each feature, the mean feature value change and the distance spanned by the 95% limits of agreement were normalized to the mean feature value, yielding normalized range of agreement (nRoA) and normalized bias (nBias). Using Wilcoxon signed rank tests, nRoA and nBias were compared with values computed previously in 27 healthy patient scans (mean voxel size: 0.67mm×0.67mm×1mm) acquired at a different institution. Results: nRoA was significantly (p<0.001) larger in cancer patients than healthy patients. Differences in nBias were not significant (p=0.23). The 20 features identified previously as having nRoA<20% for healthy patients had the lowest nRoA values in the current database, with an average increase of 5.6%. Conclusion: Despite differences in CT scanner type, scan resolution, and patient health status, the same 20 features remained stable (i.e., low variability and bias) in the absence of disease changes for databases from two institutions. Identification of

  8. Depth-dependent ordering, two-length-scale phenomena, and crossover behavior in a crystal featuring a skin layer with defects

    SciTech Connect

    Del Genio, Charo I.; Bassler, Kevin E.; Korzhenevskii, Alexander L.; Barabash, Rozaliya; Trenkler, PhD Johann; Reiter, George; Moss, Simon

    2010-01-01

    Structural defects in a crystal are responsible for the ''two-length-scale'' behavior in which a sharp central peak is superimposed over a broad peak in critical diffuse x-ray scattering. We have previously measured the scaling behavior of the central peak by scattering from a near-surface region of a V{sub 2}H crystal, which has a first-order transition in the bulk. As the temperature is lowered toward the critical temperature, a crossover in critical behavior is seen, with the temperature range nearest to the critical point being characterized by mean-field exponents. Near the transition, a small two-phase coexistence region is observed. The values of transition and crossover temperatures decay with depth. An explanation of these experimental results is here proposed by means of a theory in which edge dislocations in the near-surface region occur in walls oriented in the two directions normal to the surface. The strain caused by the dislocation lines causes the ordering in the crystal to occur as growth of roughly cylindrically shaped regions. After the regions have reached a certain size, the crossover in the critical behavior occurs, and mean-field behavior prevails. At a still lower temperature, the rest of the material between the cylindrical regions orders via a weak first-order transition.

  9. Structural defect generation and band-structure features in the HfNi{sub 1−x}Co{sub x}Sn semiconductor

    SciTech Connect

    Romaka, V. A.; Rogl, P.; Romaka, V. V.; Stadnyk, Yu. V.; Krayovskyy, V. Ya.; Kaczorowski, D.; Nakonechnyy, I. N.; Goryn, A. M.

    2015-08-15

    The crystal and electronic structure and magnetic, energy, and kinetic properties of the n-HfNiSn semiconductor heavily doped with the Co acceptor impurity (HfNi{sub 1−x}Co{sub x}Sn) are investigated in the temperature and Co concentration ranges T = 80–400 K and N{sub A}{sup Co} ≈ 9.5 × 10{sup 19}-5.7 × 10{sup 21} cm{sup −3} (x = 0.005–0.30), respectively, and under magnetic field H ≤ 10 kOe. It is established that the degree of compensation of the semiconductor changes due to transformation of the crystal structure upon doping, which leads to the generation of acceptor and donor structural defects. The calculated electronic structure is consistent with the experiment; the HfNi{sub 1−x}Co{sub x}Sn semiconductor is shown to be a promising thermoelectric material. The results obtained are discussed within the Shklovsky-Efros model for a heavily doped and compensated semiconductor.

  10. Defect criticality index (DCI): a new methodology to significantly improve DOI sampling rate in a 45nm production environment

    NASA Astrophysics Data System (ADS)

    Sato, Yoshiyuki; Yamada, Yasuyuki; Kaga, Yasuhiro; Yamazaki, Yuuichiro; Aoki, Masami; Tsui, David; Young, Chris; Chang, Ellis

    2008-03-01

    Increasing inspection sensitivity may be necessary for capturing the smaller defects of interest (DOI) dictated by reduced minimum design features. Unfortunately, higher inspection sensitivity can result in a greater percentage of non-DOI or nuisance defect types during inline monitoring in a mass production environment. Due to the time and effort required, review sampling is usually limited to 50 to 100 defects per wafer. Determining how to select and identify critical defect types under very low sampling rate conditions, so that more yield-relevant defect Paretos can be created after SEM review, has become very important. By associating GDS clip (design layout) information with every defect, and including defect attributes such as size and brightness, a new methodology called Defect Criticality Index (DCI) has demonstrated improved DOI sampling rates.

  11. An interstitial deletion of 7.1Mb in chromosome band 6p22.3 associated with developmental delay and dysmorphic features including heart defects, short neck, and eye abnormalities.

    PubMed

    Bremer, Anna; Schoumans, Jacqueline; Nordenskjöld, Magnus; Anderlid, Britt-Marie; Giacobini, Maibritt

    2009-01-01

    Seven cases with an interstitial deletion of the short arm of chromosome 6 involving the 6p22 region have previously been reported. The clinical phenotype of these cases includes developmental delay, brain-, heart-, and kidney defects, eye abnormalities, short neck, craniofacial malformations, hypotonia, as well as clinodactyly or syndactyly. Here, we report a patient with a 7.1Mb interstitial deletion of chromosome band 6p22.3, detected by genome-wide screening array CGH. The patient is a 4-year-old girl with developmental delay and dysmorphic features including eye abnormalities, short neck, and a ventricular septum defect. The deleted region at 6p22.3 in our patient overlaps with six out of the seven previously reported cases with a 6p22-24 interstitial deletion. This enabled us to further narrow down the critical region for the 6p22 deletion phenotype to 2.2Mb. Twelve genes are mapped to the overlapping deleted region, among them the gene encoding the ataxin-1 protein, the ATXN1 gene. Mice with homozygous deletions in ATXN1 are phenotypically normal but show cognitive delay. Haploinsufficiency of ATXN1 may therefore contribute to the learning difficulties observed in the patients harboring a 6p22 deletion.

  12. [Features of the immune proteasome expression in ascite Zajdela hepatoma after implantation into Brattleboro rats with the hereditary defect of arginine-vasopressin synthesis].

    PubMed

    Mel'nikova, V I; Khegaĭ, I I; Popova, N A; Lifantseva, N V; Ivanova, L N; Zaharova, L A

    2014-01-01

    The expression of the total proteasome pool, immune proteasome subunits LMP2 and LMP7, TAP1 and TAP2 transporters, as well as RT1A molecule of MHC class I was investigated in the ascite Zajdela hepatoma at the 10th day after implantation into Brattleboro rats with the hereditary defect of hypothalamic arginine-vasopressin synthesis (AVP) and into WAG rats with normal AVP expression. In Zajdela hepatoma cells implanted into Brattleboro rats the 3-fold increase of the total proteasome pool and LMP2 level and 8-fold increase of the LMP7 level was detected by Western blotting as compared to those in WAG rats. Differences in the LMP2 and LMP7 expression suggest variations in their functions, namely the important role of LMP7 in anti-tumor immunity. The growth of Zajdela hepatoma in WAG rats was accompanied by the decreased level of total proteasome pool as well as immune proteasome expression as compared to those in Brattleboro rats during the regression of tumor. The analysis of TAP1 and TAP2 revealed the pronounced expression of these peptide transporters in Zajdela hepatoma cells implanted into Brattleboro and WAG rats. The expression level of RT1A molecule of MHC class I was increased 3 times in Zajdela hepatoma cells implanted into Brattleboro rats as compared to WAG rats. Moreover, flow cytometric analysis of CD4- and CD8-lymphocytes number in the spleen of Brattleboro and WAG rats was performed at the 10th day after implantation of Zajdela hepatoma. The increased number of CD4- and CD8-lymphocytes was observed in the spleen of Brattleboro as compared to WAG. The increased subpopulations of cytotoxic T-lymphocytes and T-helpers might promote the tumor regression in Brattleboro rats. The reduced populations of CD4- and CD8-lymphocytes in the spleen of WAG rats were accompanied by the splenomegaly and tumor progression. The data obtained suggest that AVP deficiency in Brattleboro rats leads to the increase of the immune proteasome and MHC class I expression in

  13. H9c2 and HL-1 cells demonstrate distinct features of energy metabolism, mitochondrial function and sensitivity to hypoxia-reoxygenation.

    PubMed

    Kuznetsov, Andrey V; Javadov, Sabzali; Sickinger, Stephan; Frotschnig, Sandra; Grimm, Michael

    2015-02-01

    Dysfunction of cardiac energy metabolism plays a critical role in many cardiac diseases, including heart failure, myocardial infarction and ischemia-reperfusion injury and organ transplantation. The characteristics of these diseases can be elucidated in vivo, though animal-free in vitro experiments, with primary adult or neonatal cardiomyocytes, the rat ventricular H9c2 cell line or the mouse atrial HL-1 cells, providing intriguing experimental alternatives. Currently, it is not clear how H9c2 and HL-1 cells mimic the responses of primary cardiomyocytes to hypoxia and oxidative stress. In the present study, we show that H9c2 cells are more similar to primary cardiomyocytes than HL-1 cells with regard to energy metabolism patterns, such as cellular ATP levels, bioenergetics, metabolism, function and morphology of mitochondria. In contrast to HL-1, H9c2 cells possess beta-tubulin II, a mitochondrial isoform of tubulin that plays an important role in mitochondrial function and regulation. We demonstrate that H9c2 cells are significantly more sensitive to hypoxia-reoxygenation injury in terms of loss of cell viability and mitochondrial respiration, whereas HL-1 cells were more resistant to hypoxia as evidenced by their relative stability. In comparison to HL-1 cells, H9c2 cells exhibit a higher phosphorylation (activation) state of AMP-activated protein kinase, but lower peroxisome proliferator-activated receptor gamma coactivator 1-alpha levels, suggesting that each cell type is characterized by distinct regulation of mitochondrial biogenesis. Our results provide evidence that H9c2 cardiomyoblasts are more energetically similar to primary cardiomyocytes than are atrial HL-1 cells. H9c2 cells can be successfully used as an in vitro model to simulate cardiac ischemia-reperfusion injury.

  14. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1979-01-01

    Presents two demonstrations which are intended for chemistry college students. These demonstrations are: (1) enhancement of concentration quenching by micelles; and (2) the thermite lecture demonstration. (HM)

  15. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1984-01-01

    Procedures for two demonstrations are presented. The first is a demonstration of chemiluminescence. The second is a demonstration using a secondary battery constructed from common household articles. (JN)

  16. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1978-01-01

    Presents the following chemistry lecture demonstrations and experiments: (1) a versatile kinetic demonstration; (2) the Bakelite Demonstration; (3) applying Beer's law; and (4) entropy calculations. (HM)

  17. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1988-01-01

    Details three demonstrations for use in chemistry classrooms. Includes: "A Demonstration of Corrosion by Differential Aeration"; "A Simple Demonstration of the Activation Energy Concept"; and "A Boiling Demonstration at Room Temperature." Each description includes equipment, materials, and methods. (CW)

  18. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1988-01-01

    Describes two chemistry demonstrations including a demonstration of chemical inhibition and "The Rayleigh Fountain" which demonstrates the polarity of the water molecule. Provides instructions and explanations for each demonstration. (CW)

  19. Defective autologous mixed lymphocyte reactivity in multiple sclerosis.

    PubMed Central

    Hirsch, R L

    1986-01-01

    T cells from patients with multiple sclerosis (MS) and normal controls were assessed for their ability to respond in the autologous mixed lymphocyte reaction (AMLR). Cells from stable MS patients demonstrated a significant defect in their proliferative response to non-T cells in comparison to normal controls. Despite the defective AMLR response, T cells from MS patients reacted as well as T cells from normal controls to allogeneic stimuli. Furthermore, MS non-T-cells were fully capable of stimulating allogeneic MLR responses by normal and MS T cells. Since the T4+ cell is the major subpopulation which proliferates in the AMLR, these studies suggest a functional defect in a subpopulation of T4+ cells in MS patients. Since the AMLR may represent an important mechanism by which immune responses are regulated, a defect in the ability of MS T cells to respond to autologous cells could account for several of the autoimmune features of the disease. PMID:2942317

  20. Impurity-defect complexes in hydrogenated amorphous silicon

    SciTech Connect

    Yang, L.H. ); Fong, C.Y. . Dept. of Physics); Nichols, C.S. . Dept. of Materials Science and Engineering)

    1990-11-01

    The two most outstanding features observed for dopants in hydrogenated amorphous silicon (a-Si:H) -- a shift in the Fermi level accompanied by an increase in the defect density and an absence of degenerate doping -- have previously been postulated to stem from the formation of substitutional dopant-dangling bond complexes. Using first-principles self-consistent pseudopotential calculation in conjunction with a supercell model for the amorphous network and the ability of network relaxation from the first-principles results, we have studied the electronic and structural properties of substitutional fourfold-coordinated phosphorus and boron at the second neighbor position to a dangling bond defect. We demonstrate that such impurity-defect complexes can account for the general features observed experimentally in doped a-Si:H. 16 refs., 2 figs., 1 tab.

  1. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1987-01-01

    Presented are three demonstrations for chemical education. The activities include: (1) demonstration of vapor pressure; (2) a multicolored luminol-based chemiluminescence demonstration; and (3) a Charles's Law/Vapor pressure apparatus. (RH)

  2. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1982-01-01

    Three chemistry demonstrations are described: (1) partition coefficients; (2) Rutherford simulation experiment; and (3) demonstration of the powerful oxidizing property of dimanganeseheptoxide. Background information, materials needed, and procedures are provided for each demonstration. (JN)

  3. Reflectance Demonstration.

    ERIC Educational Resources Information Center

    Kowalski, Frank

    1993-01-01

    Presents a demonstration in which a mirror "disappears" upon rotation. The author has used the demonstration with students from fourth grade up through college. Suggestions are given for making the demonstration into a permanent hallway display. (MVL)

  4. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1981-01-01

    Provides procedures for demonstrations: (1) the ferrioxalate actinometer, which demonstrates a photochemical reaction; and (2) the silver mirror, which demonstrates the reduction of a metal salt to the metal and/or the reducing power of sugars. (CS)

  5. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1985-01-01

    Background information (including chemical reactions) and procedures used are provided for (1) three buffer demonstrations and (2) a demonstration of phase transfer catalysis and carbanion formation. (JN)

  6. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1988-01-01

    Describes three flame test demonstrations including "Student-Presented Demonstrations on the Colors of Transition Metal Complexes,""A Flame Test Demonstration Device," and "Vivid Flame Tests." Preparation and procedures are discussed. Included in the first demonstration is an evaluation scheme for grading student…

  7. Tested Demonstrations

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1977-01-01

    Three demonstrations are described: paramagnetic properties of Fe(11) and Fe(111), the preparation of polyurethane foam: a lecture demonstration and the electrolysis of water-fuel cell reactions. A small discussion of the concepts demonstrated is included in each demonstration's description. (MR)

  8. Hydrogen induced optically-active defects in silicon photonic nanocavities.

    PubMed

    Boninelli, S; Franzò, G; Cardile, P; Priolo, F; Lo Savio, R; Galli, M; Shakoor, A; O'Faolain, L; Krauss, T F; Vines, L; Svensson, B G

    2014-04-21

    We demonstrate intense room temperature photoluminescence (PL) from optically active hydrogen- related defects incorporated into crystalline silicon. Hydrogen was incorporated into the device layer of a silicon on insulator (SOI) wafer by two methods: hydrogen plasma treatment and ion implantation. The room temperature PL spectra show two broad PL bands centered at 1300 and 1500 nm wavelengths: the first one relates to implanted defects while the other band mainly relates to the plasma treatment. Structural characterization reveals the presence of nanometric platelets and bubbles and we attribute different features of the emission spectrum to the presence of these different kind of defects. The emission is further enhanced by introducing defects into photonic crystal (PhC) nanocavities. Transmission electron microscopy analyses revealed that the isotropicity of plasma treatment causes the formation of a higher defects density around the whole cavity compared to the ion implantation technique, while ion implantation creates a lower density of defects embedded in the Si layer, resulting in a higher PL enhancement. These results further increase the understanding of the nature of optically active hydrogen defects and their relation with the observed photoluminescence, which will ultimately lead to the development of intense and tunable crystalline silicon light sources at room temperature.

  9. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1987-01-01

    Provides instructions on conducting four demonstrations for the chemistry classroom. Outlines procedures for demonstrations dealing with coupled oscillations, the evaporation of liquids, thioxanthone sulfone radical anion, and the control of variables and conservation of matter. (TW)

  10. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1978-01-01

    Presents two demonstrations; one on Boyle's Law, to illustrate the gas law and serve as a challenging problem for the students; the other is a modified Color Blind Traffic Light demonstration in which the oscillating reactions were speeded up. (GA)

  11. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1978-01-01

    Two demonstrations are described which are suitable for introductory chemistry classes. The first involves the precipitation of silver, and the second is a demonstration of the relationship between rate constants and equilibrium constants using water and beakers. (BB)

  12. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1990-01-01

    Presented are two demonstrations; "Heat of Solution and Colligative Properties: An Illustration of Enthalpy and Entropy," and "A Vapor Pressure Demonstration." Included are lists of materials and experimental procedures. Apparatus needed are illustrated. (CW)

  13. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1989-01-01

    Presented are two demonstrations including a variation of the iodine clock reaction, and a simple demonstration of refractive index. The materials, procedures, and a discussion of probable results are given for each. (CW)

  14. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1981-01-01

    Presents: (1) a simple demonstration which illustrates the driving force of entropy using the familiar effects of the negative thermal expansion coefficient of rubber; and (2) a demonstration of tetrahedral bonding using soap films. (CS)

  15. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1981-01-01

    Two demonstrations are described: (1) red cabbage and electrolysis of water to bring together acid/base and electrochemical concepts; and (2) a model to demonstrate acid/base conjugate pairs utilizing magnets. (SK)

  16. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1987-01-01

    Describes two classroom chemistry demonstrations which focus on the descriptive chemistry of bromine and iodine. Outlines the chemicals and equipment needed, experimental procedures, and discussion of one demonstration of the oxidation states of bromine and iodine, and another demonstration of the oxidation states of iodine. (TW)

  17. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Sands, Robert; And Others

    1982-01-01

    Procedures for two demonstrations are provided. The solubility of ammonia gas in water is demonstrated by introducing water into a closed can filled with the gas, collapsing the can. The second demonstration relates scale of standard reduction potentials to observed behavior of metals in reactions with hydrogen to produce hydrogen gas. (Author/JN)

  18. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1985-01-01

    List of materials needed, procedures used, and results obtained are provided for two demonstrations. The first is an inexpensive and quick method for demonstrating column chromatography of plant pigments of spinach extract. The second is a demonstration of cathodic protection by impressed current. (JN)

  19. Demonstrating Diffusion

    ERIC Educational Resources Information Center

    Foy, Barry G.

    1977-01-01

    Two demonstrations are described. Materials and instructions for demonstrating movement of molecules into cytoplasm using agar blocks, phenolphthalein, and sodium hydroxide are given. A simple method for demonstrating that the rate of diffusion of a gas is inversely proportional to its molecular weight is also presented. (AJ)

  20. Molecular and cellular analysis of the DNA repair defect in a patient in Xeroderma pigmentosum complementation group D who has the clinical features of Xeroderma pigmentosum and Cockayne syndrome

    SciTech Connect

    Broughton, B.C.; Thompson, A.F.; Harcourt, S.A.; Cole, J.; Arlett, C.F.; Lehmann, A.R.; Vermeulen, W.; Hoeijmakers, J.H.J.; Botta, E.; Stefanini, M.

    1995-01-01

    Xeroderma pigmentosum (XP) and Cockayne syndrome (CS) are quite distinct genetic disorders that are associated with defects in excision repair of UV-induced DNA damage. A few patients have been described previously with the clinical features of both disorders. In this paper we describe an individual in this category who has unusual cellular responses to UV light. We show that his cultured fibroblasts and lymphocytes are extremely sensitive to irradiation with UV-C, despite a level of nucleotide excision repair that is 30%-40% that of normal cells. The deficiency is assigned to the XP-D complementation group, and we have identified two causative mutations in the XPD gene: a gly{yields}arg change at amino acid 675 in the allele inherited from the patient`s mother and a -1 frameshift at amino acid 669 in the allele inherited from his father. These mutations are in the C-terminal 20% of the 760-amino-acid XPD protein, in a region where we have recently identified several mutations in patients with trichothiodystrophy. 44 refs., 5 figs., 2 tabs.

  1. Congenital Defects.

    ERIC Educational Resources Information Center

    Goldman, Allen S.; And Others

    There are two general categories (not necessarily mutually exclusive) of congenital defects: (1) abnormalities that have an hereditary basis, such as single and multiple genes, or chromosomal abberration; and (2) abnormalities that are caused by nonhereditary factors, such as malnutrition, maternal disease, radiation, infections, drugs, or…

  2. Light Localization by Defects in Optically Induced Photonic Structures

    NASA Astrophysics Data System (ADS)

    Yang, Jianke; Wang, Xiaosheng; Wang, Jiandong; Chen, Zhigang

    In the past ten years, there has blossomed an interest in the study of collective behavior of wave propagation in periodic waveguide arrays and photonic lattices [1-3]. The unique bandgap structures of these periodic media, coupled with nonlinear effects, give rise to many types of novel soliton structures [1- 26]. On the other hand, it is well known that one of the unique and most interesting features of photonic band-gap structures is a fundamentally different way of waveguiding by defects in otherwise uniformly periodic structures. Such waveguiding has been demonstrated with an "air-hole" in photonic crystal fibers (PCF) for optical waves [27, 28], in an isolated defect in two-dimensional arrays of dielectric cylinders for microwaves [29-31], and recently in all-solid PCF with a lower-index core [32, 33]. In addition, laser emission based on photonic defect modes has been realized in a number of experiments [34-38]. In one-dimensional (1D) fabricated semiconductor waveguide arrays, previous experiments have investigated nonlinearity-induced escape from a defect state [39] and interactions of discrete solitons with structural defects [40] (see also [41]). Despite the above efforts, theoretical understanding on defect guiding was still limited, and experimental demonstrations of defect guiding was still scarce. In addition, when nonlinear effects are significant, how defect guiding is affected by nonlinearity is largely an open issue. Recently, in a series of theoretical and experimental studies, we optically induced 1D, 2D and ringlike photonic lattices with single-site negative defects in photorefractive crystals, and investigated their linear and nonlinear light guiding properties [42-48]. This work will be reviewed in this Chapter. In addition, we present the first experimental demonstration of nonlinear defect modes which undergoes nonlinear propagation through the defects. Our work not only has a direct link to technologically important systems of periodic

  3. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1983-01-01

    Describes a lecture demonstration of a solid state phase transition using a thermodynamic material which changes state at room temperature. Also describes a demonstration on kinetics using a "Big Bang" (trade mark) calcium carbide cannon. Indicates that the cannon is safe to use. (JN)

  4. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1989-01-01

    Presented are two chemistry demonstrations: (1) an alternative method for the demonstration of the properties of alkali metals, water is added to small amounts of metal; (2) an exploration of the properties of hydrogen, helium, propane, and carbon dioxide using an open trough and candle. (MVL)

  5. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1986-01-01

    Outlines a simple, inexpensive way of demonstrating electroplating using the reaction between nickel ions and copper metal. Explains how to conduct a demonstration of the electrolysis of water by using a colored Na2SO4 solution as the electrolyte so that students can observe the pH changes. (TW)

  6. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1982-01-01

    Three chemistry demonstrations are described: (1) modification of copper catalysis demonstration apparatus; (2) experiments in gas-liquid chromatography with simple gas chromatography at room temperature; and (3) equilibria in silver arsenate-arsenic acid and silver phosphate-phosphoric acid systems. Procedures and materials needed are provided.…

  7. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1980-01-01

    Two demonstrations are described: (1) a variant of preparing purple benzene by phase transfer catalysis with quaternary ammonium salts and potassium permanganate in which crown ethers are used; (2) a corridor or "hallway" demonstration in which unknown molecular models are displayed and prizes awarded to students correctly identifying the…

  8. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1984-01-01

    Background information and procedures are provided for a second part to the dichromate volcano demonstration. The green ash produced during the demonstration is reduced to metal using aluminothermy (Goldschmide process). Also describes suitable light sources and spectroscopes for student observation of emission spectra in lecture halls. (JN)

  9. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1983-01-01

    Free radical chlorination of methane is used in organic chemistry to introduce free radical/chain reactions. In spite of its common occurrence, demonstrations of the reaction are uncommon. Therefore, such a demonstration is provided, including background information, preparation of reactants/reaction vessel, introduction of reactants, irradiation,…

  10. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1983-01-01

    Discusses a supplement to the "water to rose" demonstration in which a pink color is produced. Also discusses blood buffer demonstrations, including hydrolysis of sodium bicarbonate, simulated blood buffer, metabolic acidosis, natural compensation of metabolic acidosis, metabolic alkalosis, acidosis treatment, and alkalosis treatment. Procedures…

  11. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1990-01-01

    Presented are three demonstrations: "The Construction and Use of Commercial Voltaic Cell Displays in Freshman Chemistry"; Dramatizing Isotopes: Deuterated Ice Cubes Sink"; and "A Simple Apparatus to Demonstrate Differing Gas Diffusion Rates (Graham's Law)." Materials, procedures, and safety considerations are discussed. (CW)

  12. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1987-01-01

    Describes two laboratory demonstrations in chemistry. One uses dry ice, freon, and freezer bags to demonstrate volume changes, vapor-liquid equilibrium, a simulation of a rain forest, and vaporization. The other uses the clock reaction technique to illustrate fast reactions and kinetic problems in releasing carbon dioxide during respiration. (TW)

  13. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1980-01-01

    Described is a demonstration utilized to measure the heat of vaporization using the Clausius-Clapeyron equation. Explained is that when measurement is made as part of a demonstration, it raises student's consciousness that chemistry is experimentally based. (Author/DS)

  14. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1985-01-01

    Two demonstrations are described. The first (useful as an introduction to kinetics) shows how the rate of a reaction is fast at first and then gradually decreases to zero when one reactant has been used up. The second is a gas density demonstration using 1,1,2-trichloro-1,2,2-trifluoro ethane. (JN)

  15. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1986-01-01

    Provides three descriptions of demonstrations used in various chemistry courses. Includes the use of a simple demonstration model to illustrate principles of chromatography, techniques for using balloons to teach about the behavior of gases, and the use of small concentrations of synthetic polyelectrolytes to induce the flocculation hydrophobic…

  16. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1983-01-01

    Provides directions for setup and performance of two demonstrations. The first demonstrates the principles of Raoult's Law; using a simple apparatus designed to measure vapor pressure. The second illustrates the energy available from alcohol combustion (includes safety precautions) using an alcohol-fueled missile. (JM)

  17. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1989-01-01

    Provided are two demonstrations for an introductory course in chemistry. The first one emphasizes the observation and the interpretation of facts to form hypotheses during the heating of a beaker of water. The second demonstration shows the liquid phase of carbon dioxide using dry ice and a pressure gauge. (YP)

  18. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1986-01-01

    Discusses the photochromic behavior of mercury(II) bis(dithizonate) in providing a colorful demonstration of the effect that visible light can have on the conformation and bonding of molecules in solution. Provides a description of the demonstration itself, along with the preparation needed to complete it. (TW)

  19. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1979-01-01

    Presents two demonstrations for classroom use related to precipitation of ferrous hydroxide and to variation of vapor pressure with temperature. The former demonstration is simple and useful when discussing solubility of ionic compounds electrode potential of transition elements, and mixed valence compounds. (Author/SA)

  20. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1986-01-01

    Describes two demonstrations designed to help chemistry students visualize certain chemical properties. One experiment uses balloons to illustrate the behavior of gases under varying temperatures and pressures. The other uses a makeshift pea shooter and a commercial model to demonstrate atomic structure and the behavior of high-speed particles.…

  1. Defects in flexoelectric solids

    NASA Astrophysics Data System (ADS)

    Mao, Sheng; Purohit, Prashant K.

    2015-11-01

    A solid is said to be flexoelectric when it polarizes in proportion to strain gradients. Since strain gradients are large near defects, we expect the flexoelectric effect to be prominent there and decay away at distances much larger than a flexoelectric length scale. Here, we quantify this expectation by computing displacement, stress and polarization fields near defects in flexoelectric solids. For point defects we recover some well known results from strain gradient elasticity and non-local piezoelectric theories, but with different length scales in the final expressions. For edge dislocations we show that the electric potential is a maximum in the vicinity of the dislocation core. We also estimate the polarized line charge density of an edge dislocation in an isotropic flexoelectric solid which is in agreement with some measurements in ice. We perform an asymptotic analysis of the crack tip fields in flexoelectric solids and show that our results share some features from solutions in strain gradient elasticity and piezoelectricity. We also compute the energy release rate for cracks using simple crack face boundary conditions and use them in classical criteria for crack growth to make predictions. Our analysis can serve as a starting point for more sophisticated analytic and computational treatments of defects in flexoelectric solids which are gaining increasing prominence in the field of nanoscience and nanotechnology.

  2. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1986-01-01

    Background information, list of materials needed, and procedures used are provided for a demonstration involving the transformation of a hydrophobic liquid to a partially hydrophobic semisolid. Safety considerations are noted. (JN)

  3. Tested Demonstrations

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1977-01-01

    Describes a room-temperature method for demonstrating phosphorescence by including samples in a polymer matrix. Also discusses the Old Nassau Reaction, a clock reaction which turns orange then black. (MLH)

  4. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1980-01-01

    Presented is a Corridor Demonstration which can be set up in readily accessible areas such as hallways or lobbies. Equipment is listed for a display of three cells (solar cells, fuel cells, and storage cells) which develop electrical energy. (CS)

  5. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Roffia, Sergio; And Others

    1988-01-01

    Reports two electrochemical demonstrations. Uses a hydrogen-oxygen fuel cell to power a clock. Includes description of methods and materials. Investigates the "potato clock" used with different fruits. Lists emf and current for various fruit and electrode combinations. (ML)

  6. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Rehfeld, D. W.; And Others

    1988-01-01

    Describes two demonstrations (1) a dust explosion using a coffee can, candle, rubber tubing, and cornstarch and (2) forming a silicate-polyvinyl alcohol polymer which can be pressed into plastic sheets or molded. Gives specific instructions. (MVL)

  7. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1987-01-01

    Presents three demonstrations suitable for undergraduate chemistry classes. Focuses on experiments with calcium carbide, the induction by iron of the oxidation of iodide by dichromate, and the classical iodine clock reaction. (ML)

  8. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L.

    1990-01-01

    Included are three demonstrations that include the phase change of ice when under pressure, viscoelasticity and colloid systems, and flame tests for metal ions. The materials, procedures, probable results, and applications to real life situations are included. (KR)

  9. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1979-01-01

    Presents a recipe for the Nylon Rope Trick, which is considered to be one of the most spectacular demonstrations in chemistry. Materials for growing the polymer and some safety precautions are given. (SA)

  10. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1988-01-01

    Describes two demonstrations for use in college chemistry classes. Includes "Spectroscopy in Large Lecture Halls" and "The Endothermic Dissolution of Ammonium Nitrate." Gives materials lists and procedures as well as a discussion of the results. (CW)

  11. Jet and flash imprint defectivity: assessment and reduction for semiconductor applications

    NASA Astrophysics Data System (ADS)

    Malloy, Matt; Litt, Lloyd C.; Johnson, Steve; Resnick, Douglas J.; Lovell, David

    2011-04-01

    Defectivity has been historically identified as a leading technical roadblock to the implementation of nanoimprint lithography for semiconductor high volume manufacturing. The lack of confidence in nanoimprint's ability to meet defect requirements originates in part from the industry's past experiences with 1X lithography and the shortage in end-user generated defect data. SEMATECH has therefore initiated a defect assessment aimed at addressing these concerns. The goal is to determine whether nanoimprint, specifically Jet and Flash Imprint Lithography from Molecular Imprints, is capable of meeting semiconductor industry defect requirements. At this time, several cycles of learning have been completed in SEMATECH's defect assessment, with promising results. J-FIL process random defectivity of < 0.1 def/cm2 has been demonstrated using a 120nm half-pitch template, providing proof of concept that a low defect nanoimprint process is possible. Template defectivity has also improved significantly as shown by a pre-production grade template at 80nm pitch. Cycles of learning continue on feature sizes down to 22nm.

  12. Photomask defect tracing, analysis, and reduction with chemically amplified resist process

    NASA Astrophysics Data System (ADS)

    Lin, Cheng-ming; Lai, Rick; Huang, W. H.; Wang, B. C.; Chen, C. Y.; Kung, C. H.; Yoo, Chue-San; Chen, Jieh-Jang; Lee, Sheng-Cha

    2003-08-01

    The features of optical proximity correction are becoming very aggressive as production technology migrates into 90nm/130 nm regime. The complicated optical proximity correction (OPC) patterns often result in un-repairable defects, a major yield loss mechanisms in a mask production line. Defect control is increasingly important. A methodology for identifying defect sources and reduction is demonstrated in this paper. The mechanisms and causes of defect formation could be determined with corresponding process step on the strength of sequence inspections. The cause of half-etched opaque defect on negative CAR process was found from PR fragment contamination of e-beam exposure step. After clean-up of e-beam chamber, yield was increased over 20%. Big pinhole defect and contact of AttPSM positive process was found on ADI step. The possible cause was poor CAR adhesion. These two type defects were decreased by modification of developing recipe, special on rinse step. Design experiment with Taguchi method was used to optimize the interactive recipe of plasma descum and rinse step on developing step of implanted layer. Average defect density was decreased from 0.99 to 0.27, and percentage of zero defect rate has been increased from 29.5 to 63.3%.

  13. Demonstration Explosion

    NASA Astrophysics Data System (ADS)

    Lee, Charles "Skip"

    1998-05-01

    Last week I did a demonstration that produced a serious explosion. After putting methanol in a big glass carboy and rotating the carboy to build up some methanol vapor, I lit the mouth of the carboy. What normally happens is a "jet engine" effect out of the mouth of the carboy. In my case, the carboy exploded. Two polycarbonate blast shields were shattered and glass was blown as far as 15 feet away. I was not seriously cut and bruised, but had I not been using the two blast shields, I would have been severely injured. At this time, I am not sure what caused the explosion. I have done this demonstration around one hundred times with no problem using the exact same amount of methanol and technique. I think it is important to get the word out that this demonstration may be more dangerous than previously thought. I would also welcome any hypotheses concerning what caused the carboy to explode.

  14. Genetic sperm defects.

    PubMed

    Chenoweth, Peter J

    2005-08-01

    Genetic sperm defects are specific sperm defects, which have been shown to have a genetic mode of transmission. Such genetic linkage, either direct or indirect, has been associated with a number of sperm defects in different species, with this number increasing with improved diagnostic capabilities. A number of sperm defects, which have proven or suspected genetic modes of transmission are discussed herein, with particular emphasis on cattle. These include: 1. Acrosome defects (knobbed, ruffled and incomplete); 2. Head defects (abnormal condensation, decapitated, round head, rolled head, nuclear crest); 3. Midpiece abnormalities ("Dag" defect, "corkscrew" defect, "pseudo-droplet" defect); 4. Tail defects ("tail stump" defect, primary ciliary dyskinesia).

  15. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1985-01-01

    Describes two demonstrations that require almost no preparation time, are visually stimulating, and present a variety of material for class discussion (with sample questions provided). The first involves a sodium bicarbonate hydrochloric acid volcano; the second involves a dissolving polystyrene cup. Procedures used and information on…

  16. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1987-01-01

    Describes two demonstrations to illustrate characteristics of substances. Outlines a method to detect the changes in pH levels during the electrolysis of water. Uses water pistols, one filled with methane gas and the other filled with water, to illustrate the differences in these two substances. (TW)

  17. Tested Demonstrations

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1976-01-01

    Describes two demonstrations: one that illustrates the attainment of equilibrium in first-order reactions by changing the volumes of two beakers of water at a specified rate, and another that illustrates the role of indicators in showing pH changes in buffer solutions. (MLH)

  18. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1989-01-01

    Discusses three broad classes of magnetic behavior: diamagnetic, paramagnetic, and ferromagnetic. Presents a simple lecture demonstration using an overhead projector to synthesize triiron tetraoxide and to show its interaction with a magnetic field and comparing it to a paramagnetic material. (MVL)

  19. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1981-01-01

    Provides instructions and a list of materials needed to demonstrate: (1) a model of the quantum mechanical atom; (2) principles involved in metal corrosion and in the prevention of this destructive process by electrochemical means; and (3) a Thermit reaction, modified to make it more dramatic and interesting for students. (SK)

  20. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L.

    1983-01-01

    An apparatus is described in which effects of pressure, volume, and temperature changes on a gas can be observed simultaneously. Includes use of the apparatus in demonstrating Boyle's, Gay-Lussac's, and Charles' Laws, attractive forces, Dalton's Law of Partial pressures, and in illustrating measurable vapor pressures of liquids and some solids.…

  1. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1984-01-01

    Two demonstrations are described. The first shows the effect of polarity on solubility. The second is based on the unexpected formation of a precipitate of barium nitrate when barium carbonate or barium phosphate is treated with dilute nitric acid. List of materials needed and procedures used are included. (JN)

  2. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1985-01-01

    Background information, procedures, and typical results obtained are provided for two demonstrations. The first involves the colorful complexes of copper(II). The second involves reverse-phase separation of Food, Drug, and Cosmetic (FD & C) dyes using a solvent gradient. (JN)

  3. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Cliche, Jean-Marie; And Others

    1988-01-01

    Describes two demonstrations: 1) the effect of polarity on solubility using sodium dichromate, TTE, ligroin, and water to form nonpolar-polar-nonpolar layers with the polar layer being colored; 2) determination of egg whites to be yellow by determining the content of yellow colored riboflavin in the egg white. (MVL)

  4. Inspecting rapidly moving surfaces for small defects using CNN cameras

    NASA Astrophysics Data System (ADS)

    Blug, Andreas; Carl, Daniel; Höfler, Heinrich

    2013-04-01

    A continuous increase in production speed and manufacturing precision raises a demand for the automated detection of small image features on rapidly moving surfaces. An example are wire drawing processes where kilometers of cylindrical metal surfaces moving with 10 m/s have to be inspected for defects such as scratches, dents, grooves, or chatter marks with a lateral size of 100 μm in real time. Up to now, complex eddy current systems are used for quality control instead of line cameras, because the ratio between lateral feature size and surface speed is limited by the data transport between camera and computer. This bottleneck is avoided by "cellular neural network" (CNN) cameras which enable image processing directly on the camera chip. This article reports results achieved with a demonstrator based on this novel analogue camera - computer system. The results show that computational speed and accuracy of the analogue computer system are sufficient to detect and discriminate the different types of defects. Area images with 176 x 144 pixels are acquired and evaluated in real time with frame rates of 4 to 10 kHz - depending on the number of defects to be detected. These frame rates correspond to equivalent line rates on line cameras between 360 and 880 kHz, a number far beyond the available features. Using the relation between lateral feature size and surface speed as a figure of merit, the CNN based system outperforms conventional image processing systems by an order of magnitude.

  5. Development and functional evaluation of biomimetic silicone surfaces with hierarchical micro/nano-topographical features demonstrates favourable in vitro foreign body response of breast-derived fibroblasts.

    PubMed

    Kyle, Daniel J T; Oikonomou, Antonios; Hill, Ernie; Bayat, Ardeshir

    2015-06-01

    Reproducing extracellular matrix topographical cues, such as those present within acellular dermal matrix (ADM), in synthetic implant surfaces, may augment cellular responses, independent of surface chemistry. This could lead to enhanced implant integration and performance while reducing complications. In this work, the hierarchical micro and nanoscale features of ADM were accurately and reproducibly replicated in polydimethylsiloxane (PDMS), using an innovative maskless 3D grayscale fabrication process not previously reported. Human breast derived fibroblasts (n=5) were cultured on PDMS surfaces and compared to commercially available smooth and textured silicone implant surfaces, for up to one week. Cell attachment, proliferation and cytotoxicity, in addition to immunofluorescence staining, SEM imaging, qRT-PCR and cytokine array were performed. ADM PDMS surfaces promoted cell adhesion, proliferation and survival (p=<0.05), in addition to increased focal contact formation and spread fibroblast morphology when compared to commercially available implant surfaces. PCNA, vinculin and collagen 1 were up-regulated in fibroblasts on biomimetic surfaces while IL8, TNFα, TGFβ1 and HSP60 were down-regulated (p=<0.05). A reduced inflammatory cytokine response was also observed (p=<0.05). This study represents a novel approach to the development of functionalised biomimetic prosthetic implant surfaces which were demonstrated to significantly attenuate the acute in vitro foreign body reaction to silicone.

  6. Defect reduction of high-density full-field patterns in jet and flash imprint lithography

    NASA Astrophysics Data System (ADS)

    Singh, Lovejeet; Luo, Kang; Ye, Zhengmao; Xu, Frank; Haase, Gaddi; Curran, David; LaBrake, Dwayne; Resnick, Douglas; Sreenivasan, S. V.

    2011-04-01

    Imprint lithography has been shown to be an effective technique for replication of nano-scale features. Jet and Flash Imprint Lithography (J-FIL) involves the field-by-field deposition and exposure of a low viscosity resist deposited by jetting technology onto the substrate. The patterned mask is lowered into the fluid which then quickly flows into the relief patterns in the mask by capillary action. Following this filling step, the resist is crosslinked under UV radiation, and then the mask is removed leaving a patterned resist on the substrate. Acceptance of imprint lithography for manufacturing will require demonstration that it can attain defect levels commensurate with the defect specifications of high end memory devices. Typical defectivity targets are on the order of 0.10/cm2. This work summarizes the results of defect inspections focusing on two key defect types; random non-fill defects occurring during the resist filling process and repeater defects caused by interactions with particles on the substrate. Non-fill defectivity must always be considered within the context of process throughput. The key limiting throughput step in an imprint process is resist filling time. As a result, it is critical to characterize the filling process by measuring non-fill defectivity as a function of fill time. Repeater defects typically have two main sources; mask defects and particle related defects. Previous studies have indicated that soft particles tend to cause non-repeating defects. Hard particles, on the other hand, can cause either resist plugging or mask damage. In this work, an Imprio 500 twenty wafer per hour (wph) development tool was used to study both defect types. By carefully controlling the volume of inkjetted resist, optimizing the drop pattern and controlling the resist fluid front during spreading, fill times of 1.5 seconds were achieved with non-fill defect levels of approximately 1.2/cm2. Longevity runs were used to study repeater defects and a nickel

  7. Quantum defect analysis of HD photoionization

    SciTech Connect

    Du, N.Y.; Greene, C.H.

    1986-11-15

    A multichannel quantum defect calculation is shown to reproduce most observed features in several portions of the HD photoabsorption spectrum. The rovibrational frame transformation theory of Atabek, Dill, and Jungen is reformulated in terms of a quantum defect matrix. The calculation accounts for spectral regions far from dissociation thresholds despite its neglect of g--u mixing.

  8. GASIS demonstration

    SciTech Connect

    Vidas, E.H.

    1995-04-01

    A prototype of the GASIS database and retrieval software has been developed and is the subject of this poster session and computer demonstration. The prototype consists of test or preliminary versions of the GASIS Reservoir Data System and Source Directory datasets and the software for query and retrieval. The prototype reservoir database covers the Rocky Mountain region and contains the full GASIS data matrix (all GASIS data elements) that will eventually be included on the CD-ROM. It is populated for development purposes primarily by the information included in the Rocky Mountain Gas Atlas. The software has been developed specifically for GASIS using Foxpro for Windows. The application is an executable file that does not require Foxpro to run. The reservoir database software includes query and retrieval, screen display, report generation, and data export functions. Basic queries by state, basin, or field name will be assisted by scrolling selection lists. A detailed query screen will allow record selection on the basis of any data field, such as depth, cumulative production, or geological age. Logical operators can be applied to any-numeric data element or combination of elements. Screen display includes a {open_quotes}browse{close_quotes} display with one record per row and a detailed single record display. Datasets can be exported in standard formats for manipulation with other software packages. The Source Directory software will allow record retrieval by database type or subject area.

  9. Adaptive classifier for steel strip surface defects

    NASA Astrophysics Data System (ADS)

    Jiang, Mingming; Li, Guangyao; Xie, Li; Xiao, Mang; Yi, Li

    2017-01-01

    Surface defects detection system has been receiving increased attention as its precision, speed and less cost. One of the most challenges is reacting to accuracy deterioration with time as aged equipment and changed processes. These variables will make a tiny change to the real world model but a big impact on the classification result. In this paper, we propose a new adaptive classifier with a Bayes kernel (BYEC) which update the model with small sample to it adaptive for accuracy deterioration. Firstly, abundant features were introduced to cover lots of information about the defects. Secondly, we constructed a series of SVMs with the random subspace of the features. Then, a Bayes classifier was trained as an evolutionary kernel to fuse the results from base SVMs. Finally, we proposed the method to update the Bayes evolutionary kernel. The proposed algorithm is experimentally compared with different algorithms, experimental results demonstrate that the proposed method can be updated with small sample and fit the changed model well. Robustness, low requirement for samples and adaptive is presented in the experiment.

  10. Five Facts about Congenital Heart Defects

    MedlinePlus

    ... Features Five Facts about Congenital Heart Defects Language: English Español (Spanish) Recommend on Facebook Tweet Share Compartir ... Folic Acid : Helping to Ensure a Healthy Pregnancy. ( English or Spanish ) Ten Tips to Prevent Infections during ...

  11. Comparison of fast 3D simulation and actinic inspection for EUV masks with buries defects

    SciTech Connect

    Clifford, C. H.; Wiraatmadja, S.; Chan, T. T.; Neureuther, A. R.; Goldberg, K. A.; Mochi, I.; Liang, T.

    2009-02-23

    Aerial images for isolated defects and the interactions of defects with features are compared between the Actinic Inspection Tool (AIT) at Lawrence Berkeley National Laboratory (LBNL) and the fast EUV simulation program RADICAL. Comparisons between AIT images from August 2007 and RADICAL simulations are used to extract aberrations. At this time astigmatism was the dominant aberration with a value of 0.55 waves RMS. Significant improvements in the imaging performance of the AIT were made between August 2007 and December 2008. A good match will be shown between the most recent AIT images and RADICAL simulations without aberrations. These comparisons will demonstrate that a large defect, in this case 7nm tall on the surface, is still printable even if it is centered under the absorber line. These comparisons also suggest that the minimum defect size is between 1.5nm and 0.8nm surface height because a 1.5nm defect was printable but a 0.8nm was not. Finally, the image of a buried defect near an absorber line through focus will demonstrate an inversion in the effect of the defect from a protrusion of the dark line into the space to a protrusion of the space into the line.

  12. The essential echocardiographic features of tetralogy of Fallot.

    PubMed

    Silverman, Norman H

    2013-12-01

    This presentation will demonstrate the essential features of tetralogy of Fallot in the infant and child before surgery, as well as some noteworthy features in the foetus. The four features, namely, subpulmonary stenosis, ventricular septal defect, aortic override, and right ventricular hypertrophy, can all be easily demonstrated by echocardiography. In addition, morphology of the pulmonary valve and the main and branch pulmonary arteries can be seen. The position of the coronary arteries and the major variants of proximal coronary anatomy can be defined. The arch anatomy and the presence of associated major aortopulmonary collateral arteries can be defined. All these features can be demonstrated in the foetus as well, after the first trimester, and the presence of major aortopulmonary collateral arteries can be seen more clearly because the lungs, being fluid filled, aid in ultrasound and do not provide the barrier that the air-filled lung presents after birth.

  13. Facts about Birth Defects

    MedlinePlus

    ... and Palate Clubfoot Craniosynostosis Down Syndrome Eye Defects Fetal Alcohol Syndrome Disorders Gastroschisis Heart Defects Coarctation of the Aorta ... grow and develop. For some birth defects, like fetal alcohol syndrome, we know the cause. But for most birth ...

  14. Atrial septal defect (ASD)

    MedlinePlus

    ... other heart defects of the ventricular septum and mitral valve . Secundum defects can be a single, small ... Sometimes, open-heart surgery may be needed to repair the defect. The type of surgery is more ...

  15. Single Ventricle Defects

    MedlinePlus

    ... Healthy Heart Function Common Types of Heart Defects - Aortic Valve Stenosis (AVS) - Atrial Septal Defect (ASD) - Coarctation of the Aorta (CoA) - Complete Atrioventricular Canal defect (CAVC) - d-Transposition ...

  16. Neural Tube Defects

    MedlinePlus

    Neural tube defects are birth defects of the brain, spine, or spinal cord. They happen in the first month ... she is pregnant. The two most common neural tube defects are spina bifida and anencephaly. In spina ...

  17. Enhancing radiation tolerance by controlling defect mobility and migration pathways in multicomponent single-phase alloys

    NASA Astrophysics Data System (ADS)

    Lu, Chenyang; Niu, Liangliang; Chen, Nanjun; Jin, Ke; Yang, Taini; Xiu, Pengyuan; Zhang, Yanwen; Gao, Fei; Bei, Hongbin; Shi, Shi; He, Mo-Rigen; Robertson, Ian M.; Weber, William J.; Wang, Lumin

    2016-12-01

    A grand challenge in material science is to understand the correlation between intrinsic properties and defect dynamics. Radiation tolerant materials are in great demand for safe operation and advancement of nuclear and aerospace systems. Unlike traditional approaches that rely on microstructural and nanoscale features to mitigate radiation damage, this study demonstrates enhancement of radiation tolerance with the suppression of void formation by two orders magnitude at elevated temperatures in equiatomic single-phase concentrated solid solution alloys, and more importantly, reveals its controlling mechanism through a detailed analysis of the depth distribution of defect clusters and an atomistic computer simulation. The enhanced swelling resistance is attributed to the tailored interstitial defect cluster motion in the alloys from a long-range one-dimensional mode to a short-range three-dimensional mode, which leads to enhanced point defect recombination. The results suggest design criteria for next generation radiation tolerant structural alloys.

  18. Enhancing radiation tolerance by controlling defect mobility and migration pathways in multicomponent single-phase alloys

    PubMed Central

    Lu, Chenyang; Niu, Liangliang; Chen, Nanjun; Jin, Ke; Yang, Taini; Xiu, Pengyuan; Zhang, Yanwen; Gao, Fei; Bei, Hongbin; Shi, Shi; He, Mo-Rigen; Robertson, Ian M.; Weber, William J.; Wang, Lumin

    2016-01-01

    A grand challenge in material science is to understand the correlation between intrinsic properties and defect dynamics. Radiation tolerant materials are in great demand for safe operation and advancement of nuclear and aerospace systems. Unlike traditional approaches that rely on microstructural and nanoscale features to mitigate radiation damage, this study demonstrates enhancement of radiation tolerance with the suppression of void formation by two orders magnitude at elevated temperatures in equiatomic single-phase concentrated solid solution alloys, and more importantly, reveals its controlling mechanism through a detailed analysis of the depth distribution of defect clusters and an atomistic computer simulation. The enhanced swelling resistance is attributed to the tailored interstitial defect cluster motion in the alloys from a long-range one-dimensional mode to a short-range three-dimensional mode, which leads to enhanced point defect recombination. The results suggest design criteria for next generation radiation tolerant structural alloys. PMID:27976669

  19. Enhancing radiation tolerance by controlling defect mobility and migration pathways in multicomponent single-phase alloys

    DOE PAGES

    Lu, Chenyang; Niu, Liangliang; Chen, Nanjun; ...

    2016-12-15

    A grand challenge in material science is to understand the correlation between intrinsic properties and defect dynamics. Radiation tolerant materials are in great demand for safe operation and advancement of nuclear and aerospace systems. Unlike traditional approaches that rely on microstructural and nanoscale features to mitigate radiation damage, this study demonstrates enhancement of radiation tolerance with the suppression of void formation by two orders magnitude at elevated temperatures in equiatomic single-phase concentrated solid solution alloys, and more importantly, reveals its controlling mechanism through a detailed analysis of the depth distribution of defect clusters and an atomistic computer simulation. The enhancedmore » swelling resistance is attributed to the tailored interstitial defect cluster motion in the alloys from a long-range one-dimensional mode to a short-range three-dimensional mode, which leads to enhanced point defect recombination. Finally, the results suggest design criteria for next generation radiation tolerant structural alloys.« less

  20. Enhancing radiation tolerance by controlling defect mobility and migration pathways in multicomponent single-phase alloys

    SciTech Connect

    Lu, Chenyang; Niu, Liangliang; Chen, Nanjun; Jin, Ke; Yang, Taini; Xiu, Pengyuan; Zhang, Yanwen; Gao, Fei; Bei, Hongbin; Shi, Shi; He, Mo-Rigen; Robertson, Ian M.; Weber, William J.; Wang, Lumin

    2016-12-15

    A grand challenge in material science is to understand the correlation between intrinsic properties and defect dynamics. Radiation tolerant materials are in great demand for safe operation and advancement of nuclear and aerospace systems. Unlike traditional approaches that rely on microstructural and nanoscale features to mitigate radiation damage, this study demonstrates enhancement of radiation tolerance with the suppression of void formation by two orders magnitude at elevated temperatures in equiatomic single-phase concentrated solid solution alloys, and more importantly, reveals its controlling mechanism through a detailed analysis of the depth distribution of defect clusters and an atomistic computer simulation. The enhanced swelling resistance is attributed to the tailored interstitial defect cluster motion in the alloys from a long-range one-dimensional mode to a short-range three-dimensional mode, which leads to enhanced point defect recombination. Finally, the results suggest design criteria for next generation radiation tolerant structural alloys.

  1. Automatic classification of blank substrate defects

    NASA Astrophysics Data System (ADS)

    Boettiger, Tom; Buck, Peter; Paninjath, Sankaranarayanan; Pereira, Mark; Ronald, Rob; Rost, Dan; Samir, Bhamidipati

    2014-10-01

    Technology Center (MPMask). The Calibre ADC tool was qualified on production mask blanks against the manual classification. The classification accuracy of ADC is greater than 95% for critical defects with an overall accuracy of 90%. The sensitivity to weak defect signals and locating the defect in the images is a challenge we are resolving. The performance of the tool has been demonstrated on multiple mask types and is ready for deployment in full volume mask manufacturing production flow. Implementation of Calibre ADC is estimated to reduce the misclassification of critical defects by 60-80%.

  2. Origin of highly active metal-organic framework catalysts: defects? Defects!

    PubMed

    Canivet, J; Vandichel, M; Farrusseng, D

    2016-03-14

    This article provides a comprehensive review of the nature of catalytic sites in MOFs. In the last decade, a number of striking studies have reported outstanding catalytic activities of MOFs. In all cases, the authors were intrigued as it was unexpected from the ideal structure. We demonstrate here that (surface) defects are at the origin of the catalytic activities for the reported examples. The vacancy of ligands or linkers systematically generates (surface) terminations which can possibly show Lewis and/or Brønsted acido-basic features. The engineering of catalytic sites at the nodes by the creation of defects (on purpose) appears today as a rational approach for the design of active MOFs. Similarly to zeolite post-treatments, post-modifications of MOFs by linker or metal cation exchange appear to be methods of choice. Despite the mild acidity of defective MOFs, we can account for very active MOFs in a number of catalytic applications which show higher performances than zeolites or benchmark catalysts.

  3. Online feature selection with streaming features.

    PubMed

    Wu, Xindong; Yu, Kui; Ding, Wei; Wang, Hao; Zhu, Xingquan

    2013-05-01

    We propose a new online feature selection framework for applications with streaming features where the knowledge of the full feature space is unknown in advance. We define streaming features as features that flow in one by one over time whereas the number of training examples remains fixed. This is in contrast with traditional online learning methods that only deal with sequentially added observations, with little attention being paid to streaming features. The critical challenges for Online Streaming Feature Selection (OSFS) include 1) the continuous growth of feature volumes over time, 2) a large feature space, possibly of unknown or infinite size, and 3) the unavailability of the entire feature set before learning starts. In the paper, we present a novel Online Streaming Feature Selection method to select strongly relevant and nonredundant features on the fly. An efficient Fast-OSFS algorithm is proposed to improve feature selection performance. The proposed algorithms are evaluated extensively on high-dimensional datasets and also with a real-world case study on impact crater detection. Experimental results demonstrate that the algorithms achieve better compactness and higher prediction accuracy than existing streaming feature selection algorithms.

  4. Formation, migration, and clustering of point defects in CuInSe2 from first principles

    NASA Astrophysics Data System (ADS)

    Oikkonen, L. E.; Ganchenkova, M. G.; Seitsonen, A. P.; Nieminen, R. M.

    2014-08-01

    The electronic properties of high-efficiency CuInSe2 (CIS)-based solar cells are affected by the microstructural features of the absorber layer, such as point defect types and their distribution. Recently, there has been controversy over whether some of the typical point defects in CIS—VCu, VSe, InCu, CuIn—can form stable complexes in the material. In this work, we demonstrate that the presence of defect complexes during device operational time can be justified by taking into account the thermodynamic and kinetic driving forces acting behind defect microstructure formation. Our conclusions are backed up by thorough state-of-the-art calculations of defect interaction potentials as well as the activation barriers surrounding the complexes. Defect complexes such as InCu-2VCu, InCu-CuIn, and VSe-VCu are shown to be stable against thermal dissociation at device operating temperatures, but can anneal out within tens of minutes at temperatures higher than 150-200 °C (VCu-related complexes) or 400 °C (antisite pair). Our results suggest that the presence of these complexes can be controlled via growth temperatures, which provides a mechanism for tuning the electronic activity of defects and the device altogether.

  5. Effect of aspect ratio and surface defects on the photocatalytic activity of ZnO nanorods

    PubMed Central

    Zhang, Xinyu; Qin, Jiaqian; Xue, Yanan; Yu, Pengfei; Zhang, Bing; Wang, Limin; Liu, Riping

    2014-01-01

    ZnO, aside from TiO2, has been considered as a promising material for purification and disinfection of water and air, and remediation of hazardous waste, owing to its high activity, environment-friendly feature and lower cost. However, their poor visible light utilization greatly limited their practical applications. Herein, we demonstrate the fabrication of different aspect ratios of the ZnO nanorods with surface defects by mechanical-assisted thermal decomposition method. The experiments revealed that ZnO nanorods with higher aspect ratio and surface defects show significantly higher photocatalytic performances. PMID:24699790

  6. Air coupled ultrasonic detection of surface defects in food cans

    NASA Astrophysics Data System (ADS)

    Seco, Fernando; Ramón Jiménez, Antonio; del Castillo, María Dolores

    2006-06-01

    In this paper, we describe an ultrasonic inspection system used for detection of surface defects in food cans. The system operates in the pulse-echo mode and analyses the 220 kHz ultrasonic signal backscattered by the object. The classification of samples into valid or defective is achieved with χ2 statistics and the k nearest neighbour method, applied to features computed from the envelope of the ultrasonic echo. The performance of the system is demonstrated empirically in detection of the presence of the pull tab on the removable lid of easy-open food cans, in a production line. It is found that three factors limit the performance of the classification: the misalignment of the samples, their separation of the ultrasonic transducer, and the vibration of the conveyor belt. When these factors are controlled, classification success rates between 94% and 99% are achieved.

  7. Automated Defect Classification Using AN Artificial Neural Network

    NASA Astrophysics Data System (ADS)

    Chady, T.; Caryk, M.; Piekarczyk, B.

    2009-03-01

    The automated defect classification algorithm based on artificial neural network with multilayer backpropagation structure was utilized. The selected features of flaws were used as input data. In order to train the neural network it is necessary to prepare learning data which is representative database of defects. Database preparation requires the following steps: image acquisition and pre-processing, image enhancement, defect detection and feature extraction. The real digital radiographs of welded parts of a ship were used for this purpose.

  8. AUTOMATED DEFECT CLASSIFICATION USING AN ARTIFICIAL NEURAL NETWORK

    SciTech Connect

    Chady, T.; Caryk, M.; Piekarczyk, B.

    2009-03-03

    The automated defect classification algorithm based on artificial neural network with multilayer backpropagation structure was utilized. The selected features of flaws were used as input data. In order to train the neural network it is necessary to prepare learning data which is representative database of defects. Database preparation requires the following steps: image acquisition and pre-processing, image enhancement, defect detection and feature extraction. The real digital radiographs of welded parts of a ship were used for this purpose.

  9. Context-based automated defect classification system using multiple morphological masks

    DOEpatents

    Gleason, Shaun S.; Hunt, Martin A.; Sari-Sarraf, Hamed

    2002-01-01

    Automatic detection of defects during the fabrication of semiconductor wafers is largely automated, but the classification of those defects is still performed manually by technicians. This invention includes novel digital image analysis techniques that generate unique feature vector descriptions of semiconductor defects as well as classifiers that use these descriptions to automatically categorize the defects into one of a set of pre-defined classes. Feature extraction techniques based on multiple-focus images, multiple-defect mask images, and segmented semiconductor wafer images are used to create unique feature-based descriptions of the semiconductor defects. These feature-based defect descriptions are subsequently classified by a defect classifier into categories that depend on defect characteristics and defect contextual information, that is, the semiconductor process layer(s) with which the defect comes in contact. At the heart of the system is a knowledge database that stores and distributes historical semiconductor wafer and defect data to guide the feature extraction and classification processes. In summary, this invention takes as its input a set of images containing semiconductor defect information, and generates as its output a classification for the defect that describes not only the defect itself, but also the location of that defect with respect to the semiconductor process layers.

  10. Holographic Experiments on Defects

    NASA Astrophysics Data System (ADS)

    Wapler, Matthias C.

    Using the AdS/CFT correspondence, we study the anisotropic charge transport properties of both supersymmetric and nonsupersymmetric matter fields on (2+1)-dimensional defects coupled to a (3+1)-dimensional { N} = 4 SYM "heat bath." We focus on the cases of a finite external background magnetic field, finite net charge density and finite mass and their combinations. In this context, we also discuss the limitations due to operator mixing that appears in a few situations and that we ignore in our analysis. At high frequencies, we discover a spectrum of quasiparticle resonances due to the magnetic field and finite density and at small frequencies, we perform a Drude-like expansion around the DC limit. Both of these regimes display many generic features and some features that we attribute to strong coupling, such as a minimum DC conductivity and an unusual behavior of the "cyclotron" and plasmon frequencies, which become related to the resonances found in the conformal case in an earlier paper. We further study the hydrodynamic regime and the relaxation properties, from which the system displays a set of different possible transitions to the collisionless regime. The mass dependence can be cast in two regimes: a generic relativistic behavior dominated by the UV and a nonlinear hydrodynamic behavior dominated by the IR. In the massless case, we furthermore extend earlier results from the literature to find an interesting selfduality under a transformation of the conductivity and the exchange of density and magnetic field.

  11. [Congenital defects and incapacity].

    PubMed

    Jouve de la Barreda, Nicolás

    2009-01-01

    As a whole the congenital defects constitute an important section of the medical attention affecting near 3% of the population. A 15% of spontaneous abortions take place of which the greater frequency corresponds to the chromosome anomalies (25%) and the monogenic mutations (20%) and in a lesser extent to the effects of teratogenic agents. Between the genetic causes determining the congenital defects the mutations that affect genes acting in the early stages of development occupy a main place. These alterations can affect to homeotic genes or monogenic systems that act during the critical phases of the organogenesis. It seems evident that an alteration in the expression of a necessary gene for the appearance of a morphogenetic change constitutes the angular stone to understand resurging of a malformation or discapacity. In the last years has been demonstrated the importance of the teratogenic or environmental agents on the delicate internal physiological balance during the critical stages of the development. In this context must be included the inductive environmental factors inducing epigenetic modifications in the early stage of the development of the embryos produced by fertilization in vitro.

  12. Toward defect guard-banding of EUV exposures by full chip optical wafer inspection of EUV mask defect adders

    NASA Astrophysics Data System (ADS)

    Halle, Scott D.; Meli, Luciana; Delancey, Robert; Vemareddy, Kaushik; Crispo, Gary; Bonam, Ravi; Burkhardt, Martin; Corliss, Daniel

    2015-03-01

    The detection of EUV mask adder defects has been investigated with an optical wafer defect inspection system employing a methodology termed Die-to-"golden" Virtual Reference Die (D2VRD). Both opaque and clear type mask absorber programmed defects were inspected and characterized over a range of defect sizes, down to (4x mask) 40 nm. The D2VRD inspection system was capable of identifying the corresponding wafer print defects down to the limit of the defect printability threshold at approximately 30 nm (1x wafer). The efficacy of the D2VRD scheme on full chip wafer inspection to suppress random process defects and identify real mask defects is demonstrated. Using defect repeater analysis and patch image classification of both the reference die and the scanned die enables the unambiguous identification of mask adder defects.

  13. Influence of material quality and process-induced defects on semiconductor device performance and yield

    NASA Technical Reports Server (NTRS)

    Porter, W. A.; Mckee, W. R.

    1974-01-01

    An overview of major causes of device yield degradation is presented. The relationships of device types to critical processes and typical defects are discussed, and the influence of the defect on device yield and performance is demonstrated. Various defect characterization techniques are described and applied. A correlation of device failure, defect type, and cause of defect is presented in tabular form with accompanying illustrations.

  14. Atrioventricular Canal Defect

    MedlinePlus

    ... al. Clinical manifestations, pathophysiology, and diagnosis of atrioventricular (AV) canal defects. http://www.uptodate.com/home. Accessed ... CE, et al. Management and outcome of atrioventricular (AV) canal defects. http://www.uptodate.com/home. Accessed ...

  15. Birth Defects (For Parents)

    MedlinePlus

    ... to create energy. Examples of metabolic defects include Tay-Sachs disease , a fatal disease that affects the central nervous ... called recessive inheritance and includes conditions such as Tay-Sachs disease and cystic fibrosis . A disease or defect also ...

  16. Backside defect printability for contact layer with different reticle blank material

    NASA Astrophysics Data System (ADS)

    Ning, Guoxiang; Holfeld, Christian; Fischer, Daniel; Ackmann, Paul; Holfeld, Andre; Kurth, Karin; Sczyrba, Martin; Hertzsch, Tino; Seltmann, Rolf; Ho, Angeline; GN, Fang H.

    2012-11-01

    Backside defects are out of focus during wafer exposure by the mask thickness and cannot be directly imaged on wafer. However, backside defects will induce transmission variation during wafer exposure. When the size of backside defect is larger than 200 microns, the shadow of such particles will locally change the illumination conditions of the mask patterns and may result in a long range critical dimension (CD) variation on wafer depending on numerical aperture (NA) and pupil shape. Backside defects will affect both wafer CD and critical dimension uniformity (CDU), especially for two-dimensional (2D) structures. This paper focuses on the printability of backside defects on contact layer using annular and quadrupole illumination mode, as well as using different reticle blank material. It also targets for gaining better understanding of critical sizes of backside defects on contact layer for different reticle blanks. We have designed and manufactured two test reticles with repeating patterns of 28nm and 40nm technology node of contact layers. Programmed chrome defects of varying size are placed on the backside opposite to the repeating front side patterns in order to measure the spatial variation of transmission and wafer CD. The test mask was printed on a bare silicon wafer, and the printed features measured for size by spatial sampling. We have investigated two contact layers with different illumination conditions. One is advance binary with single exposure; another is phase shift mask with double exposure. Wafer CD variation for different backside defect sizes are demonstrated for the two contact layers. The comparison between backside defect size with inter-field and intra-field CD variation is also discussed.

  17. A WSI approach towards defect/fault-tolerant reconfigurable serial systems

    NASA Astrophysics Data System (ADS)

    Chen, Wei; Mavor, John; Denyer, Peter B.; Renshaw, David

    1988-06-01

    A superchip for realizing ultra-large-scale integrated (ULSI) systems based on a wafer-scale integrated (WSI) circuit concept, which incorporates defect/fault tolerance and system reconfiguration, is introduced. The key features of the central architectural component, a large crossbar switch matrix, are described. A prototype has been fabricated in silicon technology. Hypothetical processor examples demonstrate the power of the superchip approach, and design/performance figures are discussed.

  18. [Detection of Hawthorn Fruit Defects Using Hyperspectral Imaging].

    PubMed

    Liu, De-hua; Zhang, Shu-juan; Wang, Bin; Yu, Ke-qiang; Zhao, Yan-ru; He, Yong

    2015-11-01

    feature of 86 Hawthorn could be recognized. Lastly, the detect precision of bruised, insect damage and two-defect samples is 95.65%, 86.67% and 100%, respectively. This investigation demonstrated that hyperspectral imaging technology could detect the defects of bruise, insect damage, calyx, and stem-end in hawthorn fruit in qualitative analysis and feature detection which provided a theoretical reference for the defects nondestructive detection of hawthorn fruit.

  19. Defect-tolerant extreme ultraviolet nanoscale printing.

    PubMed

    Urbanski, L; Isoyan, A; Stein, A; Rocca, J J; Menoni, C S; Marconi, M C

    2012-09-01

    We present a defect-free lithography method for printing periodic features with nanoscale resolution using coherent extreme ultraviolet light. This technique is based on the self-imaging effect known as the Talbot effect, which is produced when coherent light is diffracted by a periodic mask. We present a numerical simulation and an experimental verification of the method with a compact extreme ultraviolet laser. Furthermore, we explore the extent of defect tolerance by testing masks with different defect layouts. The experimental results are in good agreement with theoretical calculations.

  20. Optical manipulation and imaging of assemblies of topological defects and colloids in liquid crystals

    NASA Astrophysics Data System (ADS)

    Trivedi, Rahul P.

    Liquid Crystals (LCs) have proven to be important for electro-optic device applications such as displays, spatial light modulators, non-mechanical beam-steerers, etc. Owing to their unique mechanical, electrical, and optical properties, they are also being explored for wide array of advanced technological applications such as biosensors, tunable lenses, distributed feedback lasers, muscle-like actuators, etc. The thesis explores LC media from the standpoint of controlling their elastic and optical properties by generating and manipulating assemblies of defects and colloidal particles. To achieve the goal of optically manipulating these configurations comprising defects and particles at microscale with an unprecedented control, and then to visualize the resultant molecular director patterns, requires development of powerful optical system. The thesis discusses design and implementation of such an integrated system capable of 3D holographic optical manipulation and multi-modal 3D imaging (in nonlinear optical modes like multiphoton fluorescence, coherent anti-Stokes Raman scattering, etc.) and how they are used to extensively study a vast number of LC based systems. Understanding of LCs and topological defects go hand in hand. Appreciation of defects leads to their precise control, which in turn can lead to applications. The thesis describes discovery of optically generated stable, quasiparticle-like, localized defect structures in a LC cell, that we call "Torons". Torons enable twist of molecules in three dimensions and resemble both Skyrmion-like and Hopf fibration features. Under different conditions of generation, we optically realize an intriguing variety of novel solitonic defect structures comprising rather complicated configurations of point and line topological defects. Introducing colloidal particles to LC systems imparts to these hybrid material system a fascinating degree of richness of properties on account of colloidal assemblies supported by networks

  1. Fermi level dependent native defect formation: Consequences for metal-semiconductor and semiconductor-semiconductor interfaces

    SciTech Connect

    Walukiewicz, W.

    1988-02-01

    The amphoteric native defect model of the Schottky barrier formation is used to analyze the Fermi level pinning at metal/semiconductor interfaces for submonolayer metal coverages. It is assumed that the energy required for defect generation is released in the process of surface back-relaxation. Model calculations for metal/GaAs interfaces show a weak dependence of the Fermi level pinning on the thickness of metal deposited at room temperature. This weak dependence indicates a strong dependence of the defect formation energy on the Fermi level, a unique feature of amphoteric native defects. This result is in very good agreement with experimental data. It is shown that a very distinct asymmetry in the Fermi level pinning on p- and n-type GaAs observed at liquid nitrogen temperatures can be understood in terms of much different recombination rates for amphoteric native defects in those two types of materials. Also, it is demonstrated that the Fermi level stabilization energy, a central concept of the amphoteric defect system, plays a fundamental role in other phenomena in semiconductors such as semiconductor/semiconductor heterointerface intermixing and saturation of free carrier concentration. 33 refs., 6 figs.

  2. Topological defect lasers

    NASA Astrophysics Data System (ADS)

    Knitter, Sebastian; Fatt Liew, Seng; Xiong, Wen; Guy, Mikhael I.; Solomon, Glenn S.; Cao, Hui

    2016-01-01

    We introduce a topological defect to a regular photonic crystal defect cavity with anisotropic unit cell. Spatially localized resonances are formed and have high quality factor. Unlike the regular photonic crystal defect states, the localized resonances in the topological defect structures support powerflow vortices. Experimentally we realize lasing in the topological defect cavities with optical pumping. This work shows that the spatially inhomogeneous variation of the unit cell orientation adds another degree of freedom to the control of lasing modes, enabling the manipulation of the field pattern and energy flow landscape.

  3. Congenital defects of sheep.

    PubMed

    Dennis, S M

    1993-03-01

    With increasing incrimination of viruses, plants, and drugs as causes of ovine congenital defects, concerted efforts are required to identify environmental teratogens. Expanding knowledge of congenital defects requires studying as many defective lambs as possible; recording and documenting; detailed diagnostic examinations; genetic analyses and chromosomal examinations, whenever possible; and field investigations. Adopting standardized classification, terminology, and diagnostic procedures should improve descriptions, diagnoses, and interdisciplinary exchange of information. That, in turn, should improve our knowledge of and diagnosis of congenital defects of sheep in the future. Finally, veterinary clinicians and diagnosticians are encouraged to take an interest in congenital defects and teratology.

  4. Defect production in ceramics

    SciTech Connect

    Zinkle, S.J.; Kinoshita, C.

    1997-08-01

    A review is given of several important defect production and accumulation parameters for irradiated ceramics. Materials covered in this review include alumina, magnesia, spinel silicon carbide, silicon nitride, aluminum nitride and diamond. Whereas threshold displacement energies for many ceramics are known within a reasonable level of uncertainty (with notable exceptions being AIN and Si{sub 3}N{sub 4}), relatively little information exists on the equally important parameters of surviving defect fraction (defect production efficiency) and point defect migration energies for most ceramics. Very little fundamental displacement damage information is available for nitride ceramics. The role of subthreshold irradiation on defect migration and microstructural evolution is also briefly discussed.

  5. Postdevelopment defect evaluation

    NASA Astrophysics Data System (ADS)

    Miyahara, Osamu; Kiba, Yukio; Ono, Yuko

    2001-08-01

    Reduction of defects after development is a critical issue in photolithography. A special category of post development defects is the satellite defect which is located in large exposed areas generally in proximity to large unexposed regions of photoresist. We have investigated the formation of this defect type on ESCAP and ACETAL DUV resists with and without underlying organic BARCs, In this paper, we will present AFM and elemental analysis data to determine the origin of the satellite defect. Imaging was done on a full-field Nikon 248nm stepper and resist processing was completed on a TEL CLEAN TRACK ACT 8 track. Defect inspection and review were performed on a KLA-Tencor and Hitachi SEM respectively. Results indicate that the satellite defect is generated on both BARC and resist films and defect counts are dependent on the dark erosion. Elemental analysis indicates that the defects are composed of sulfur and nitrogen compounds. We suspect that the defect is formed as a result of a reaction between PAG, quencher and TMAH. This defect type is removed after a DIW re-rinse.

  6. Ventricular Septal Defect (For Parents)

    MedlinePlus

    ... Atrial Septal Defect Ventricular Septal Defect Heart and Circulatory System ECG (Electrocardiogram) Anesthesia - What to Expect Tetralogy of ... Atrial Septal Defect Ventricular Septal Defect Heart and Circulatory System Contact Us Print Resources Send to a friend ...

  7. Ventricular Septal Defect (For Parents)

    MedlinePlus

    ... Atrial Septal Defect Ventricular Septal Defect Heart and Circulatory System ECG (Electrocardiogram) Anesthesia - What to Expect Tetralogy of ... Atrial Septal Defect Ventricular Septal Defect Heart and Circulatory System Contact Us Print Resources Send to a Friend ...

  8. Discrete Sources Method for light scattering analysis of non-axisymmetric features of a substrate

    NASA Astrophysics Data System (ADS)

    Eremin, Yuri; Wriedt, Thomas

    2016-01-01

    The Discrete Sources Method (DSM) has been extended to analyze polarized light scattering by non-axial symmetric nano-sized features on a plane substrate. A detailed description of the corresponding numerical scheme is provided. Using a "fictitious" particle approach the new DSM model enables to consider scattering from such substrate defects as a line bump and a line pit. The developed computer model has been employed for demonstrating the ability to perform a comparative analysis of light scattering from such line features. Simulation results corresponding to the Differential Scattering Cross-Section (DSC) and the integral response for P/S polarized light are presented. It was found that the integral response can change by an order of magnitude depending on the orientation of the linear defect with respect to the direction of the incident laser light. In addition, it was shown that some defects can turn out to be "invisible" if an oblique angle of incidence is chosen.

  9. Sinus Venosus Atrial Septal Defect

    DTIC Science & Technology

    2010-04-01

    chest CT was performed to evaluate for pulmonary embolism (figure 2). The chest radiograph (figure 1) demonstrates increased central pulmonary ...Fig. 5 Sinus venosus defect at birth . The shaded area in purple represents the sinus venosum. The anomalous right pulmonary venous anatomy...department (ED) with chest pain and an ankle fracture after being hit by a car while riding a horse. Chest imaging noted enlarged central pulmonary

  10. Thoracoabdominal wall defect with complete ectopia cordis and gastroschisis: a case report and review of the literature.

    PubMed

    Pepper, Michael A; Fishbein, Gregory A; Teitell, Michael A

    2013-01-01

    Ventral wall defects are extremely rare anomalies that are likely caused by the failure of the ventral wall to close during week 4 of development. We report a case of severe thoracoabdominal wall defect including complete thoracic ectopia cordis and gastroschisis. This combination represents a novel constellation of findings in a single patient. This unique case further demonstrates an anatomically normal heart with age-appropriate development and an intact diaphragm. We review the literature of other reports and discussions of entities that share overlapping features with this case.

  11. Robust defect segmentation in woven fabrics

    SciTech Connect

    Sari-Sarraf, H.; Goddard, J.S. Jr.

    1997-12-01

    This paper describes a robust segmentation algorithm for the detection and localization of woven fabric defects. The essence of the presented segmentation algorithm is the localization of those events (i.e., defects) in the input images that disrupt the global homogeneity of the background texture. To this end, preprocessing modules, based on the wavelet transform and edge fusion, are employed with the objective of attenuating the background texture and accentuating the defects. Then, texture features are utilized to measure the global homogeneity of the output images. If these images are deemed to be globally nonhomogeneous (i.e., defects are present), a local roughness measure is used to localize the defects. The utility of this algorithm can be extended beyond the specific application in this work, that is, defect segmentation in woven fabrics. Indeed, in a general sense, this algorithm can be used to detect and to localize anomalies that reside in images characterized by ordered texture. The efficacy of this algorithm has been tested thoroughly under realistic conditions and as a part of an on-line fabric inspection system. Using over 3700 images of fabrics, containing 26 different types of defects, the overall detection rate of this approach was 89% with a localization accuracy of less than 0.2 inches and a false alarm rate of 2.5%.

  12. Phenol dissociation on pristine and defective graphene

    NASA Astrophysics Data System (ADS)

    Widjaja, Hantarto; Oluwoye, Ibukun; Altarawneh, Mohammednoor; Hamra, A. A. B.; Lim, H. N.; Huang, N. M.; Yin, Chun-Yang; Jiang, Zhong-Tao

    2017-03-01

    Phenol (C6H5O‒H) dissociation on both pristine and defective graphene sheets in terms of associated enthalpic requirements of the reaction channels was investigated. Here, we considered three common types of defective graphene, namely, Stone-Wales, monovacancy and divacancy configurations. Theoretical results demonstrate that, graphene with monovacancy creates C atoms with dangling bond (unpaired valence electron), which remains particularly useful for spontaneous dissociation of phenol into phenoxy (C6H5O) and hydrogen (H) atom. The reactions studied herein appear barrierless with reaction exothermicity as high as 2.2 eV. Our study offers fundamental insights into another potential application of defective graphene sheets.

  13. Model based defect characterization in composites

    NASA Astrophysics Data System (ADS)

    Roberts, R.; Holland, S.

    2017-02-01

    Work is reported on model-based defect characterization in CFRP composites. The work utilizes computational models of the interaction of NDE probing energy fields (ultrasound and thermography), to determine 1) the measured signal dependence on material and defect properties (forward problem), and 2) an assessment of performance-critical defect properties from analysis of measured NDE signals (inverse problem). Work is reported on model implementation for inspection of CFRP laminates containing multi-ply impact-induced delamination, with application in this paper focusing on ultrasound. A companion paper in these proceedings summarizes corresponding activity in thermography. Inversion of ultrasound data is demonstrated showing the quantitative extraction of damage properties.

  14. The NASA telerobot technology demonstrator

    NASA Technical Reports Server (NTRS)

    Schenker, P. S.; French, R. L.; Sirota, A. R.; Matijevic, J. R.

    1987-01-01

    The ongoing development of a telerobot technology demonstrator is reported. The demonstrator is implemented as a laboratory-based research testbed, and will show proof-of-concept for supervised automation of space assembly, servicing, and repair operations. The demonstrator system features a hierarchically layered intelligent control architecture which enables automated planning and run-time sequencing of complex tasks by a supervisory human operator. The demonstrator also provides a full bilateral force-reflecting hand control teleoperations capability. The operator may switch smoothly between the automated and teleoperated tasking modes in run-time, either on a preplanned or operator-designated basis.

  15. NIL defect performance toward high volume mass production

    NASA Astrophysics Data System (ADS)

    Hatano, Masayuki; Kobayashi, Kei; Kashiwagi, Hiroyuki; Tokue, Hiroshi; Kono, Takuya; Tetsuro, Nakasugi; Choi, Eun Hyuk; Jung, Wooyung

    2016-03-01

    A low cost alternative lithographic technology is desired to meet with the decreasing feature size of semiconductor devices. Nanoimprint lithography (NIL) is one of the candidates for alternative lithographic technologies. NIL has advantages such as good resolution, critical dimension (CD) uniformity and smaller line edge roughness (LER). 4 On the other hand, NIL involves some risks. Defectivity is the most critical issue in NIL. The progress in the defect reduction on templates shows great improvement recently. In other words, the defect reduction of the NIIL process is a key to apply NIL to mass production. In this paper, we describe the evaluation results of the defect performance of NIL using an up-to-date tool, Canon FPA-1100 NZ2, and discuss the future potential of NIL in terms of defectivity. The impact of various kinds defects, such as the non-filling defect, plug defect, line collapse, and defects on replica templates are discussed. We found that non-fill defects under the resist pattern cause line collapse. It is important to prevent line collapse. From these analyses based on actual NIL defect data on long-run stability, we will show the way to reduce defects and the possibility of NIL in device high volume mass production. For the past one year, we have been are collaborating with SK Hynix to bring this promising technology into mainstream manufacturing. This work is the result of this collaboration.

  16. Why Search for Congenital Defects?

    PubMed Central

    Collins, John F.

    1966-01-01

    The causation of congenital malformation is receiving increased study. In Canada, epidemiologic surveys are being planned, based upon the institution of Provincial Registries to which physicians and other agencies will voluntarily report cases coming to their attention. The literature in regard to prevalence studies of congenital cardiac defects in school children is reviewed. Over the past 25 years, studies employing the proposed technique demonstrated a rising trend, from 1.4 per 1000 to 2.6 per 1000. By contrast, specific surveys for congenital cardiac defect carried out by expert personnel using radiographs and electrocardiographs, resulted in essentially uniform rates, approximating 5 to 6 per 1000. It is concluded that the latter is a superior technique of epidemiologic survey over the “Central Registry” method, and should command a due proportion of health resources directed towards congenital malformation research. PMID:5914837

  17. Microtubule defects & Neurodegeneration.

    PubMed

    Baird, Fiona J; Bennett, Craig L

    2013-12-06

    One of the major challenges facing the long term survival of neurons is their requirement to maintain efficient axonal transport over long distances. In humans as large, long-lived vertebrates, the machinery maintaining neuronal transport must remain efficient despite the slow accumulation of cell damage during aging. Mutations in genes encoding proteins which function in the transport system feature prominently in neurologic disorders. Genes known to cause such disorders and showing traditional Mendelian inheritance have been more readily identified. It has been more difficult, however, to isolate factors underlying the complex genetics contributing to the more common idiopathic forms of neurodegenerative disease. At the heart of neuronal transport is the rail network or scaffolding provided by neuron specific microtubules (MTs). The importance of MT dynamics and stability is underscored by the critical role tau protein plays in MT-associated stabilization versus the dysfunction seen in Alzheimer's disease, frontotemporal dementia and other tauopathies. Another example of the requirement for tight regulation of MT dynamics is the need to maintain balanced levels of post-translational modification of key MT building-blocks such as α-tubulin. Tubulins require extensive polyglutamylation at their carboxyl-terminus as part of a novel post-translational modification mechanism to signal MT growth versus destabilization. Dramatically, knock-out of a gene encoding a deglutamylation family member causes an extremely rapid cell death of Purkinje cells in the ataxic mouse model, pcd. This review will examine a range of neurodegenerative conditions where current molecular understanding points to defects in the stability of MTs and axonal transport to emphasize the central role of MTs in neuron survival.

  18. Systematic defect donor levels in III-V and II-VI semiconductors revealed by hybrid functional density-functional theory

    NASA Astrophysics Data System (ADS)

    Petretto, Guido; Bruneval, Fabien

    2015-12-01

    The identification of defect levels from photoluminescence spectroscopy is a useful but challenging task. Density-functional theory (DFT) is a highly valuable tool to this aim. However, the semilocal approximations of DFT that are affected by a band gap underestimation are not reliable to evaluate defect properties, such as charge transition levels. It is now established that hybrid functional approximations to DFT improve the defect description in semiconductors. Here we demonstrate that the use of hybrid functionals systematically stabilizes donor defect states in the lower part of the band gap for many defects, impurities or vacancies, in III-V and in II-VI semiconductors, even though these defects are usually considered as acceptors. These donor defect states are a very general feature and, to the best of our knowledge, have been overlooked in previous studies. The states we identify here may challenge the older assignments to photoluminescent peaks. Though appealing to screen quickly through the possible stable charge states of a defect, semilocal approximations should not be trusted for that purpose.

  19. Nonequilibrium occupancy of tail states and defects in a-Si:H: Implications for defect structure

    NASA Astrophysics Data System (ADS)

    Schumm, G.; Jackson, W. B.; Street, R. A.

    1993-11-01

    A detailed investigation of the electron and hole occupancy of tail states in undoped amorphous silicon (a-Si:H) as well as changes in the dangling-bond occupancy as a function of excitation intensity was carried out using light-induced electron-spin-resonance (LESR) measurements. For very thick films the band-tail electron and hole densities are not proportional. Over a wide range of excitation conditions the excess hole density is constant, suggesting the presence of charged defects with a density that is 5-10 times larger than the neutral defect density in annealed or as-grown a-Si:H. Light soaking increases mainly the neutral defect density. The dependence of the excess hole density on film thickness and absorption profiles indicates that this effect is a bulk property, which may be masked in thinner films by the comparatively high interface defect density. Model calculations of nonequilibrium occupation statistics confirm the experimental results. For a defect distribution that includes charged defects, the calculations suggest a very small positive LESR signature of the dangling bond, in spite of the high density of charged defects in the material, as a necessary consequence of the asymmetries observed between electron and hole capture rates and tail-state distributions. The calculations demonstrate that the lack of this signature does not imply a defect structure that contains predominantly neutral defects.

  20. Comparison of defects identified through Minnesota's Birth Defects Information System And Vital Records, 2006-2008.

    PubMed

    Banerjee, Emily; Zabel, Erik; Alexander, Bruce

    2012-01-01

    The purpose of this study was to examine the differences in birth defects identified through passive and active surveillance systems in Hennepin and Ramsey counties in Minnesota, 2006-2008. This was done by comparing birth defects identified on birth certificates through the Minnesota Department of Health's Office of the State Registrar's Birth and Death Registry (vital records) with those identified by the Minnesota Department of Health's Birth Defects Information System (BDIS), an active birth defects surveillance system. The study population included 73,059 babies born to residents of Hennepin and Ramsey counties. There were 1,882 babies that either vital records and/or BDIS identified as having 1 or more birth defects. Cases identified by BDIS were then linked with matching birth certificates found in the vital records database. Using BDIS as the gold standard, it was observed that the vital records database had an overall underreporting rate of 89% when all broad groups of defects were compared, and 72% when 11 specific defects tracked by both registries were compared. The sensitivity and positive predictive values of vital records to identify cases were also compared using BDIS as the gold standard, and demonstrated low sensitivities for most of the 11 comparable defects (range: 0% for tracheoesophageal fistula to 80% for anencephalus). These observations indicate that BDIS has significantly improved the quality of birth defects surveillance in Minnesota.

  1. Axillary shoulder with exaggerated rotation: the Hill-Sachs defect.

    PubMed

    Rafert, J A; Long, B W; Hernandez, E M; Kreipke, D L

    1990-01-01

    One of the most common fractures of the humeral head resulting from an anterior dislocation is the Hill-Sachs defect. Other special radiographic positions to demonstrate this injury may prove difficult for the patient to assume and maintain. An axillary shoulder projection with exaggerated external rotation is easy to position and clearly demonstrates the Hill-Sachs defect.

  2. Computational mask defect review for contamination and haze inspections

    NASA Astrophysics Data System (ADS)

    Morgan, Paul; Rost, Daniel; Price, Daniel; Corcoran, Noel; Satake, Masaki; Hu, Peter; Peng, Danping; Yonenaga, Dean; Tolani, Vikram; Wolf, Yulian; Shah, Pinkesh

    2013-09-01

    the mask manufacturing process. The latter characterization qualifies real defect signatures, such as pin-dots or pin-holes, extrusions or intrusions, assist-feature or dummy-fill defects, writeerrors or un-repairable defects, chrome-on-shifter or missing chrome-from-shifter defects, particles, etc., and also false defect signatures, such as those due to inspection tool registration or image alignment, interlace artifacts, CCD camera artifacts, optical shimmer, focus errors, etc. Such qualitative characterization of defects has enabled better inspection tool SPC and process defect control in the mask shop. In this paper, the same computational approach to defect review has been extended to contamination style defect inspections, including Die-to-Die reflected, and non Die-to-Die or single-die inspections. In addition to the computational methods used for transmitted aerial images, defects detected in die-to-die reflected light mode are analyzed based on special defect and background coloring in reflected-light, and other characteristics to determine the exact type and severity. For those detected in the non Die-to-Die mode, only defect images are available from the inspection tool. Without a reference, i.e., defect-free image, it is often difficult to determine the true nature or impact of the defect in question. Using a combination of inspection-tool modeling and image inversion techniques, Luminescent's LAIPHTM system generates an accurate reference image, and then proceeds with automated defect characterization as if the images were simply from a die-to-die inspection. The disposition of contamination style defects this way, filters out >90% of false and nuisance defects that otherwise would have been manually reviewed or measured on AIMSTM. Such computational defect review, unifying defect disposition across all available inspection modes, has been imperative to ensuring no yield losses due to errors in operator defect classification on one hand, and on the other

  3. Demonstration-Based Training: A Review of Instructional Features

    DTIC Science & Technology

    2010-10-01

    Review of Neuroscience , 27, 169–192. Robinson, J. C. (1982). Developing managers through behavior modeling. San Diego, CA: Learning Concepts. Russell...Journal of the Human Factors and Ergonomics Society Michael A. Rosen, Eduardo Salas, Davin Pavlas, Randy Jensen, Dan Fu and Donald Lampton...Eduardo Salas, and Davin Pavlas, University of Central Florida, Orlando, Randy Jensen and Dan Fu, Stottler Henke Associates, Inc., San Mateo

  4. Diabetes mellitus and birth defects

    PubMed Central

    Correa, Adolfo; Gilboa, Suzanne M.; Besser, Lilah M.; Botto, Lorenzo D.; Moore, Cynthia A.; Hobbs, Charlotte A.; Cleves, Mario A.; Riehle-Colarusso, Tiffany J.; Waller, D. Kim; Reece, E. Albert

    2016-01-01

    OBJECTIVE The purpose of this study was to examine associations between diabetes mellitus and 39 birth defects. STUDY DESIGN This was a multicenter case-control study of mothers of infants who were born with (n = 13,030) and without (n = 4895) birth defects in the National Birth Defects Prevention Study (1997–2003). RESULTS Pregestational diabetes mellitus (PGDM) was associated significantly with noncardiac defects (isolated, 7/23 defects; multiples, 13/23 defects) and cardiac defects (isolated, 11/16 defects; multiples, 8/16 defects). Adjusted odds ratios for PGDM and all isolated and multiple defects were 3.17 (95% CI, 2.20–4.99) and 8.62 (95% CI, 5.27–14.10), respectively. Gestational diabetes mellitus (GDM) was associated with fewer noncardiac defects (isolated, 3/23 defects; multiples, 3/23 defects) and cardiac defects (isolated, 3/16 defects; multiples, 2/16 defects). Odds ratios between GDM and all isolated and multiple defects were 1.42 (95% CI, 1.17–1.73) and 1.50 (95% CI, 1.13–2.00), respectively. These associations were limited generally to offspring of women with prepregnancy body mass index ≥25 kg/m2. CONCLUSION PGDM was associated with a wide range of birth defects; GDM was associated with a limited group of birth defects. PMID:18674752

  5. Defects in Calcite.

    DTIC Science & Technology

    1991-05-13

    AD-A245 645 A TRIDENT SCHOLAR PROJECT REPORT NO. 181 "DEFECTS IN CALCITE " DTTC %N FEB 5-1912 UNITED STATES NAVAL ACADEMY ANNAPOLIS, MARYLAND 92-02841...report; no. 181 (1991) "DEFECTS IN CALCITE " A Trident Scholar Project Report by Midshipman Anthony J. Kotarski, Class of 1991 U. S. Naval Academy Annapolis...REPORT TYPE AND DATES COVERED 13 May 1991 Final 1990/91 . TITLE AND SUBTITLE s. FUNDING NUMBERS DEFECTS IN CALCITE 6. AUTHOR(S) Anthony J. Kotarski 7

  6. Engaging Hill-Sachs Defects

    PubMed Central

    Burns, David; Chahal, Jaskarndip; Shahrokhi, Shahram; Henry, Patrick; Wasserstein, David; Whyne, Cari; Theodoropoulos, John S.; Ogilvie-Harris, Darrell; Dwyer, Tim

    2016-01-01

    Objectives: Anatomic studies have demonstrated that bipolar glenoid and humeral bone loss have a cumulative impact on shoulder instability, and that these defects may engage in functional positions depending on their size, location, and orientation, potentially resulting in failure of stabilization procedures. Determining which lesions pose a risk for engagement remains a challenge, with arthroscopic assessment and Itoi’s 3DCT based glenoid track method being the accepted approaches at this time. The purpose of this study was to investigate the interaction of humeral and glenoid bone defects on shoulder engagement in a cadaveric model. Two alternative approaches to predicting engagement were evaluated; 1) CT scanning the shoulder in abduction and external rotation 2) measurement of Bankart lesion width and a novel parameter, the intact anterior articular angle (IAAA), on conventional 2D multi-plane reformats. The results of these two approaches were compared to the results obtained using Itoi’s glenoid track method for predicting engagement. Methods: Hill-Sachs and Bony Bankart defects of varying size were created in 12 cadaveric upper limbs, producing 45 bipolar defect combinations. The shoulders were assessed for engagement using cone beam CT in various positions of function, from 30 to 90 degrees of both abduction and external rotation. The humeral and glenoid defects were characterized by measurement of their size, location, and orientation. Diagnostic performance measures for predicting engagement were calculated for both the abduction external rotation scan and 2D IAAA approaches using the glenoid track method as reference standard. Results: Engagement was predicted by Itoi’s glenoid track method in 24 of 45 specimens (53%). The abduction external rotation CT scan performed at 60 degrees of glenohumeral abduction (corresponding to 90 degrees of abduction relative to the trunk) and 90 degrees of external rotation predicted engagement accurately in 43 of

  7. Phase measurements of EUV mask defects

    DOE PAGES

    Claus, Rene A.; Wang, Yow-Gwo; Wojdyla, Antoine; ...

    2015-02-22

    Extreme Ultraviolet (EUV) Lithography mask defects were examined on the actinic mask imaging system, SHARP, at Lawrence Berkeley National Laboratory. Also, a quantitative phase retrieval algorithm based on the Weak Object Transfer Function was applied to the measured through-focus aerial images to examine the amplitude and phase of the defects. The accuracy of the algorithm was demonstrated by comparing the results of measurements using a phase contrast zone plate and a standard zone plate. Using partially coherent illumination to measure frequencies that would otherwise fall outside the numerical aperture (NA), it was shown that some defects are smaller than themore » conventional resolution of the microscope. We found that the programmed defects of various sizes were measured and shown to have both an amplitude and a phase component that the algorithm is able to recover.« less

  8. Phase measurements of EUV mask defects

    SciTech Connect

    Claus, Rene A.; Wang, Yow-Gwo; Wojdyla, Antoine; Benk, Markus P.; Goldberg, Kenneth A.; Neureuther, Andrew R.; Naulleau, Patrick P.; Waller, Laura

    2015-02-22

    Extreme Ultraviolet (EUV) Lithography mask defects were examined on the actinic mask imaging system, SHARP, at Lawrence Berkeley National Laboratory. Also, a quantitative phase retrieval algorithm based on the Weak Object Transfer Function was applied to the measured through-focus aerial images to examine the amplitude and phase of the defects. The accuracy of the algorithm was demonstrated by comparing the results of measurements using a phase contrast zone plate and a standard zone plate. Using partially coherent illumination to measure frequencies that would otherwise fall outside the numerical aperture (NA), it was shown that some defects are smaller than the conventional resolution of the microscope. We found that the programmed defects of various sizes were measured and shown to have both an amplitude and a phase component that the algorithm is able to recover.

  9. Nanoparticle Solubility in Liquid Crystalline Defects

    NASA Astrophysics Data System (ADS)

    Whitmer, Jonathan K.; Armas-Perez, Julio C.; Joshi, Abhijeet A.; Roberts, Tyler F.; de Pablo, Juan J.

    2013-03-01

    Liquid crystalline materials often incorporate regions (defects) where the orientational ordering present in the bulk phase is disrupted. These include point hedgehogs, line disclinations, and domain boundaries. Recently, it has been shown that defects will accumulate impurities such as small molecules, monomer subunits or nanoparticles. Such an effect is thought to be due to the alleviation of elastic stresses within the bulk phase, or to a solubility gap between a nematic phase and the isotropic defect core. This presents opportunities for encapsulation and sequestration of molecular species, in addition to the formation of novel structures within a nematic phase through polymerization and nanoparticle self-assembly. Here, we examine the solubility of nanoparticles within a coarse-grained liquid crystalline phase and demonstrate the effects of nanoparticle size and surface interactions in determining sequestration into defect regions.

  10. Exploration of defect structures on graphene.

    PubMed

    Yu, Shansheng; Zheng, Weitao

    2013-02-01

    For graphene obtained by chemical vapor deposition, there are large amount of defects in the crystalline structures. The carbon atoms from the feedstock can attack the graphene surface in annealing process, which may be one of the reasons affecting the structure of graphene. In order to explore some defect structures on graphene, we investigate the adsorption of carbon adatoms and vacancies on graphene using first-principles calculations. It is demonstrated that the adatoms can form strong covalent bonds with the graphene and the C-C dimmer adsorption may be the most prolific defect model. The C adatom can even fill simple vacancy of graphene. Our numerical simulations also show that the defect structures can lead to the splitting of the mid-gap peak of perfect graphene in the electronic structures. It is suggested that its conductivity would be lower than that of the perfect graphene, which can explain the low mobility of the charge carriers in some experiments.

  11. Toward defect-free fabrication of extreme ultraviolet photomasks

    NASA Astrophysics Data System (ADS)

    Qi, Zhengqing John; Rankin, Jed H.; Lawliss, Mark; Badger, Karen D.; Turley, Christina

    2016-04-01

    Defect-free fabrication of extreme ultraviolet (EUV) masks relies on the appropriate detection of native defects and subsequent strategies for their elimination. Commercial unavailability of actinic mask-blank inspection systems motivates the identification of an optical inspection methodology most suitable for finding relevant EUV blank defects. Studies showed that 193-nm wavelength inspection found the greatest number of printable defects as compared with rival higher-wavelength systems, establishing deep ultraviolet inspections as the blank defectivity baseline for subsequent mitigation strategies. Next, defect avoidance via pattern shifting was explored using representative 7-nm node metal/contact layer designs and 193-nm mask-blank inspection results. It was found that a significant percentage of native defects could be avoided only when the design was limited to active patterns (i.e., layouts without dummy fill). Total pattern-defect overlap remained ≤5 when metal layer blanks were chosen from the top 35% least defective substrates, while the majority of blanks remained suitable for contacts layers due to a lower active pattern density. Finally, nanomachining was used to address remaining native/multilayer defects. Native catastrophic defects were shown to recover 40% to 70% of target critical dimension after nanomachining, demonstrating the enormous potential for compensating multilayer defects.

  12. Congenital Heart Defects

    MedlinePlus

    ... Treatment can include medicines, catheter procedures, surgery, and heart transplants. The treatment depends on the type of the defect, how severe it is, and a child's age, size, and general health. NIH: National Heart, Lung, and Blood Institute

  13. Ventricular Septal Defect (VSD)

    MedlinePlus

    ... specially sized mesh device to close the hole. Hybrid procedure. A hybrid procedure uses surgical and catheter-based techniques. Access ... clinicalkey.com. Accessed Sept. 15, 2014. Konetti NR. Hybrid muscular ventricular defect closure: Surgeon or physician. Indian ...

  14. Birth defects monitoring

    SciTech Connect

    Klingberg, M.A.; Papier, C.M.; Hart, J.

    1983-01-01

    Population monitoring of birth defects provides a means for detecting relative changes in their frequency. Many varied systems have been developed throughout the world since the thalidomide tragedy of the early 1960s. Although it is difficult to pinpoint specific teratogenic agents based on rises in rates of a particular defect or a constellation of defects, monitoring systems can provide clues for hypothesis testing in epidemiological investigations. International coordination of efforts in this area resulted in the founding of the International Clearinghouse for Birth Defects Monitoring Systems (ICBDMS) in 1974. In this paper we will describe the functions and basic requirements of monitoring systems in general, and look at the development and activities of the ICBDMS. A review of known and suspected environmental teratogenic agents (eg, chemical, habitual, biological, physical, and nutritional) is also presented.

  15. A novel ATM-dependent checkpoint defect distinct from loss of function mutation promotes genomic instability in melanoma.

    PubMed

    Spoerri, Loredana; Brooks, Kelly; Chia, KeeMing; Grossman, Gavriel; Ellis, Jonathan J; Dahmer-Heath, Mareike; Škalamera, Dubravka; Pavey, Sandra; Burmeister, Bryan; Gabrielli, Brian

    2016-05-01

    Melanomas have high levels of genomic instability that can contribute to poor disease prognosis. Here, we report a novel defect of the ATM-dependent cell cycle checkpoint in melanoma cell lines that promotes genomic instability. In defective cells, ATM signalling to CHK2 is intact, but the cells are unable to maintain the cell cycle arrest due to elevated PLK1 driving recovery from the arrest. Reducing PLK1 activity recovered the ATM-dependent checkpoint arrest, and over-expressing PLK1 was sufficient to overcome the checkpoint arrest and increase genomic instability. Loss of the ATM-dependent checkpoint did not affect sensitivity to ionizing radiation demonstrating that this defect is distinct from ATM loss of function mutations. The checkpoint defective melanoma cell lines over-express PLK1, and a significant proportion of melanomas have high levels of PLK1 over-expression suggesting this defect is a common feature of melanomas. The inability of ATM to impose a cell cycle arrest in response to DNA damage increases genomic instability. This work also suggests that the ATM-dependent checkpoint arrest is likely to be defective in a higher proportion of cancers than previously expected.

  16. The Characterization of Crack-Like Defects Using Ultrasonic Images

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Velichko, A.; Drinkwater, B. W.; Wilcox, P. D.

    2010-02-01

    The use of ultrasonic arrays to image and size crack-like defects is an important area in non-destructive evaluation. The features in the ultrasonic data from a crack-like defect provide information about the size and orientation angle of the defect. In this paper, the characteristics of a crack-like defect were measured from its scattering coefficient matrix, when the angular coverage of measurement includes the specular regions of its scattering matrix. Alternatively, the imaged features for a large crack-like defect (its length more than two wavelengths) were directly used to characterize the defect through a rectangular box fitting approach. An efficient hybrid model was used to generate the full matrix of array data from samples with a defect and for a specified inspection configuration. This hybrid model combines far-field scattering coefficient matrix for defects with a ray based forward model. This model offers the potential to compile a look-up table through which defects can be classified and then sized. Good agreement was achieved between simulation and experimental results hence validating this model based approach.

  17. Defect reduction and defect stability in IMEC's 14nm half-pitch chemo-epitaxy DSA flow

    NASA Astrophysics Data System (ADS)

    Gronheid, Roel; Rincon Delgadillo, Paulina; Pathangi, Hari; Van den Heuvel, Dieter; Parnell, Doni; Chan, Boon Teik; Lee, Yu-Tsung; Van Look, Lieve; Cao, Yi; Her, YoungJun; Lin, Guanyang; Harukawa, Ryota; Nagaswami, Venkat; D'Urzo, Lucia; Somervell, Mark; Nealey, Paul

    2014-03-01

    Directed Self-Assembly (DSA) of Block Co-Polymers (BCP) has become an intense field of study as a potential patterning solution for future generation devices. The most critical challenges that need to be understood and controlled include pattern placement accuracy, achieving low defectivity in DSA patterns and how to make chip designs DSA-friendly. The DSA program at imec includes efforts on these three major topics. Specifically, in this paper the progress in DSA defectivity within the imec program will be discussed. In previous work, defectivity levels of ~560 defects/cm2 were reported and the root causes for these defects were identified, which included particle sources, material interactions and pre-pattern imperfections. The specific efforts that have been undertaken to reduce defectivity in the line/space chemoepitaxy DSA flow that is used for the imec defectivity studies are discussed. Specifically, control of neutral layer material and improved filtration during the block co-polymer manufacturing have enabled a significant reduction in the defect performance. In parallel, efforts have been ongoing to enhance the defect inspection capabilities and allow a high capture rate of the small defects. It is demonstrated that transfer of the polystyrene patterns into the underlying substrate is critical for detecting the DSA-relevant defect modes including microbridges and small dislocations. Such pattern transfer enhances the inspection sensitivity by ~10x. Further improvement through process optimization allows for substantial defectivity reduction.

  18. Nonlinear features for product inspection

    NASA Astrophysics Data System (ADS)

    Talukder, Ashit; Casasent, David P.

    1999-03-01

    Classification of real-time X-ray images of randomly oriented touching pistachio nuts is discussed. The ultimate objective is the development of a system for automated non-invasive detection of defective product items on a conveyor belt. We discuss the extraction of new features that allow better discrimination between damaged and clean items (pistachio nuts). This feature extraction and classification stage is the new aspect of this paper; our new maximum representation and discriminating feature (MRDF) extraction method computes nonlinear features that are used as inputs to a new modified k nearest neighbor classifier. In this work, the MRDF is applied to standard features (rather than iconic data). The MRDF is robust to various probability distributions of the input class and is shown to provide good classification and new ROC (receiver operating characteristic) data.

  19. SpaceFibre Demonstrator (Demonstration and Testing)

    NASA Astrophysics Data System (ADS)

    Helfers, T.; Rastetter, P.; Papadas, C.; Parkes, S.

    2014-08-01

    Currently Astrium GmbH and ISD S.A. are planning the development of a demonstrator for SpaceFibre. The SpaceFibre demonstrator will be used to execute functional performance tests and EMC (Electro Magnetic Compatibility) tests. University of Dundee is program prime contractor and provides Astrium with the SpaceFibre IP core. The work si shared between the two partners in the following way: • Astrium: Prime Contractor and Technical Coordination; FPGA Design; EMC Testing• ISD: Development of Demonstrator Board including housing, development of test bed and functional performance testingThe driving requirements for this development are:• SpaceFibre performance, while implementing it into space equivalent components• Design and MAIT of the demonstrator in such a way that representative EMC testing is possible.

  20. Defect-induced fatigue microcrack formation in cement mantle.

    PubMed

    Qi, Gang; Li, Jihui; Mouchon, W Paul; Lewis, Gladius

    2005-11-01

    Acoustic emission (AE) was used to monitor the progress of the fatigue damage process in the cement mantles of two cemented femur stem constructs that contained naturally occurring defects. After the fatigue tests, morphological features of the defects were investigated using an environmental scanning electron microscope. It showed that the regions with no visible defects were mainly microcrack free, whereas the defect regions were the main sources generating microcracks. Two types of microcracks were identified: type I and type II. Signal energies associated with type I microcracks were about an order of magnitude higher than that of type II. The microstructural investigations of the defects and the areas in the vicinity of the defects suggested their categorization into stable and unstable. The accumulative energy-time relationships revealed that stable and unstable microcrack curves had convex [formula: see text], and concave [formula: see text] shapes, respectively. The progress of fatigue microcrack formation occurred over three distinct phases: initiation, transition, and stableness.

  1. Global defect topology in nematic liquid crystals

    PubMed Central

    Machon, Thomas

    2016-01-01

    We give the global homotopy classification of nematic textures for a general domain with weak anchoring boundary conditions and arbitrary defect set in terms of twisted cohomology, and give an explicit computation for the case of knotted and linked defects in R3, showing that the distinct homotopy classes have a 1–1 correspondence with the first homology group of the branched double cover, branched over the disclination loops. We show further that the subset of those classes corresponding to elements of order 2 in this group has representatives that are planar and characterize the obstruction for other classes in terms of merons. The planar textures are a feature of the global defect topology that is not reflected in any local characterization. Finally, we describe how the global classification relates to recent experiments on nematic droplets and how elements of order 4 relate to the presence of τ lines in cholesterics. PMID:27493576

  2. Global defect topology in nematic liquid crystals

    NASA Astrophysics Data System (ADS)

    Machon, Thomas; Alexander, Gareth P.

    2016-07-01

    We give the global homotopy classification of nematic textures for a general domain with weak anchoring boundary conditions and arbitrary defect set in terms of twisted cohomology, and give an explicit computation for the case of knotted and linked defects in R3, showing that the distinct homotopy classes have a 1-1 correspondence with the first homology group of the branched double cover, branched over the disclination loops. We show further that the subset of those classes corresponding to elements of order 2 in this group has representatives that are planar and characterize the obstruction for other classes in terms of merons. The planar textures are a feature of the global defect topology that is not reflected in any local characterization. Finally, we describe how the global classification relates to recent experiments on nematic droplets and how elements of order 4 relate to the presence of τ lines in cholesterics.

  3. Defect coarsening in a biological system: the vascular cambium of cottonwood trees.

    PubMed

    Kramer, Eric M; Groves, Joseph V

    2003-04-01

    We present micrographic evidence for the annihilation of topological defect pairs and defect-mediated coarsening in the vascular cambium of cottonwood trees (Populus deltoides). We also show that a recently published mathematical model of cell orientation dynamics in the cambium reproduces many qualitative features of the defect coarsening process.

  4. Trapping of drops by wetting defects

    PubMed Central

    't Mannetje, Dieter; Ghosh, Somnath; Lagraauw, Rudy; Otten, Simon; Pit, Arjen; Berendsen, Christian; Zeegers, Jos; van den Ende, Dirk; Mugele, Frieder

    2014-01-01

    Controlling the motion of drops on solid surfaces is crucial in many natural phenomena and technological processes including the collection and removal of rain drops, cleaning technology and heat exchangers. Topographic and chemical heterogeneities on solid surfaces give rise to pinning forces that can capture and steer drops in desired directions. Here we determine general physical conditions required for capturing sliding drops on an inclined plane that is equipped with electrically tunable wetting defects. By mapping the drop dynamics on the one-dimensional motion of a point mass, we demonstrate that the trapping process is controlled by two dimensionless parameters, the trapping strength measured in units of the driving force and the ratio between a viscous and an inertial time scale. Complementary experiments involving superhydrophobic surfaces with wetting defects demonstrate the general applicability of the concept. Moreover, we show that electrically tunable defects can be used to guide sliding drops along actively switchable tracks—with potential applications in microfluidics. PMID:24721935

  5. Isolation and characterization of Pichia heedii mutants defective in xylose uptake

    SciTech Connect

    Does, A.L.; Bisson, L.F. )

    1990-11-01

    To investigate the role of xylose uptake in xylose metabolism in yeasts, we isolated a series of mutated strains of the yeast Pichia heedii which are defective in xylose utilization. Four of these demonstrated defects in xylose uptake. Overlaps between the functional or regulatory mechanisms for glucose and xylose uptake may exist in this yeast since some of the mutants defective in xylose uptake were also defective in glucose transport. None of the mutants were defective in xylose reductase or xylitol dehydrogenase activities.

  6. A Fluorescence Lecture Demonstration.

    ERIC Educational Resources Information Center

    Bozzelli, Joseph W.; Kemp, Marwin

    1982-01-01

    Describes fluorescence demonstrations related to several aspects of molecular theory and quantitized energy levels. Demonstrations use fluorescent chemical solutions having luminescence properties spanning the visible spectrum. Also describes a demonstration of spontaneous combustion of familiar substances in chlorine. (JN)

  7. ORION II bus demonstration. Demonstration report (Final)

    SciTech Connect

    Shanley, J.

    1989-02-01

    The Central New York Regional Transportation Authority conducted an 18-month demonstration to determine how the ORION II bus operates in actual service. The ORION II vehicle is a small low floor, accessible heavy duty, diesel-powered transit bus designed to meet the needs of the elderly and handicapped. It has the capacity to seat 26 passengers with 4 wheelchair lockdowns. Side and rear doors are equipped with electrically powered ramps. Eight Thomas vehicles (22-foot, 11,500 lbs, wheelchair equipped, gasoline fueled) were also tested during the demonstration period. Operations (fuel and oil usage) and maintenance (scheduled and unscheduled) data were collected and charted-out in the report as well as driver, passenger, and maintenance surveys. This report provides descriptions, photographs, and comparison charts of both the diesel-fueled ORION II transit bus and the gasoline-fueled Thomas vehicles along with the demonstration test plan, evaluations, conclusions, and survey results.

  8. Birth Defects. Matrix No. 2.

    ERIC Educational Resources Information Center

    Brent, Robert L.

    This report discusses the magnitude of the problem of birth defects, outlines advances in the birth defects field in the past decade, and identifies those areas where research is needed for the prevention, treatment, and management of birth defects. The problem of birth defects has consumed a greater portion of our health care resources because of…

  9. Local and nonlocal defect-mediated electroweak baryogenesis

    SciTech Connect

    Brandenberger, R.; Davis, A.; Prokopec, T.; Trodden, M. |||

    1996-04-01

    We consider the effects of particle transport in topological defect-mediated electroweak baryogenesis scenarios. We analyze the cases of both thin and thick defects and demonstrate an enhancement of the original mechanism in both cases due to an increased effective volume in which baryogenesis occurs. This phenomenon is a result of an imperfect cancellation between the baryons and antibaryons produced on opposite faces of the defect. {copyright} {ital 1996 The American Physical Society.}

  10. Structural birth defects associated with neural tube defects in Hawai'i from 1986 until 2001.

    PubMed

    Forrester, Mathias B; Merz, Ruth D

    2007-09-01

    Using birth defects registry data, this study identified birth defects associated with anencephaly, spina bifida, and encephalocele. Musculoskeletal defects were associated with anencephaly; central nervous system defects, gastrointestinal atresia/stenosis, genitourinary system defects, and musculoskeletal system defects with spina bifida; and central nervous system defects, respiratory defects, oral clefts, genitourinary system defects, and musculoskeletal system defects with encephalocele.

  11. A novel approach to mask defect inspection

    NASA Astrophysics Data System (ADS)

    Sagiv, Amir; Shirman, Yuri; Mangan, Shmoolik

    2008-10-01

    Memory chips, now constituting a major part of semiconductor market, posit a special challenge for inspection, as they are generally produced with the smallest half-pitch available with today's technology. This is true, in particular, to photomasks of advanced memory devices, which are at the forefront of the "low-k1" regime. In this paper we present a novel photomask inspection approach, that is particularly suitable for low-k1 layers of advanced memory chips, owing to their typical dense and periodic structure. The method we present can produce a very strong signal for small mask defects, by suppression of the modulation of the pattern's image. Unlike dark-field detection, however, here a single diffraction order associated with the pattern generates a constant "gray" background image, that is used for signal enhancement. We define the theoretical basis for the new detection technique, and show, both analytically and numerically, that it can easily achieve a detection line past the printability spec, and that in cases it is at least as sensitive as high-resolution based detection. We also demonstrate this claim experimentally on a customer mask, using the platform of Applied Material's newly released Aera2TM mask inspection tool. The high sensitivity demonstrates the important and often overlooked concept that resolution is not synonymous with sensitivity. The novel detection method is advantageous in several other aspects, such as the very simple implementation, the high throughput, and the relatively simple pre- and post-processing algorithms required for signal extraction. These features, and in particular the very high sensitivity, make this novel detection method an attractive inspection option for advanced memory devices.

  12. Wire insulation defect detector

    NASA Technical Reports Server (NTRS)

    Greulich, Owen R. (Inventor)

    2004-01-01

    Wiring defects are located by detecting a reflected signal that is developed when an arc occurs through the defect to a nearby ground. The time between the generation of the signal and the return of the reflected signal provides an indication of the distance of the arc (and therefore the defect) from the signal source. To ensure arcing, a signal is repeated at gradually increasing voltages while the wire being tested and a nearby ground are immersed in a conductive medium. In order to ensure that the arcing occurs at an identifiable time, the signal whose reflection is to be detected is always made to reach the highest potential yet seen by the system.

  13. Reconstruction of Mandibular Defects

    PubMed Central

    Chim, Harvey; Salgado, Christopher J.; Mardini, Samir; Chen, Hung-Chi

    2010-01-01

    Defects requiring reconstruction in the mandible are commonly encountered and may result from resection of benign or malignant lesions, trauma, or osteoradionecrosis. Mandibular defects can be classified according to location and extent, as well as involvement of mucosa, skin, and tongue. Vascularized bone flaps, in general, provide the best functional and aesthetic outcome, with the fibula flap remaining the gold standard for mandible reconstruction. In this review, we discuss classification and approach to reconstruction of mandibular defects. We also elaborate upon four commonly used free osteocutaneous flaps, inclusive of fibula, iliac crest, scapula, and radial forearm. Finally, we discuss indications and use of osseointegrated implants as well as recent advances in mandibular reconstruction. PMID:22550439

  14. Supersymmetric k-defects

    NASA Astrophysics Data System (ADS)

    Koehn, Michael; Trodden, Mark

    2016-04-01

    In supersymmetric theories, topological defects can have nontrivial behaviors determined purely by whether or not supersymmetry is restored in the defect core. A well-known example of this is that some supersymmetric cosmic strings are automatically superconducting, leading to important cosmological effects and constraints. We investigate the impact of nontrivial kinetic interactions, present in a number of particle physics models of interest in cosmology, on the relationship between supersymmetry and supercurrents on strings. We find that in some cases it is possible for superconductivity to be disrupted by the extra interactions.

  15. Intrinsic Bonding Defects in Transition Metal Elemental Oxides

    DTIC Science & Technology

    2006-01-01

    deposition, ALD. Spectroscopic studies have also been performed on nanocrystalline TiO2 , ZrO2, HfO2, and complex mixed oxides such as ZrTiO4, LaAlO3 and...5d-state and defect features are identified. Figure 2(b). SXPS valence band spectrum of TiO2 . 5d-state and defect features... TiO2 . 3d-state features are identified. Figure 4. Ti L3 edge XAS spectrum of TiO2 . Ti 3d J-T term split states are

  16. Computer-aided approach for customized cell-based defect reconstruction.

    PubMed

    Meyer, Ulrich; Neunzehn, Jörg; Wiesmann, Hans Peter

    2012-01-01

    Computer-aided technologies like computer-aided design (CAD), computer-aided manufacturing (CAM), and a lot of other features like finite element method (FEM) have been recently employed for use in medical ways like in extracorporeal bone tissue engineering strategies. Aim of this pilot experimental study was to test whether autologous osteoblast-like cells cultured in vitro on individualized scaffolds can be used to support bone regeneration in a clinical environment. Mandibular bone defects were surgically introduced into the mandibles of Göttinger minipigs and the scaffold of the defect site was modelled by CAD/CAM techniques. From the minipigs harvested autologous bone cells from the porcine calvaria were cultivated in bioreactors. The cultured osteoblast-like cells were seeded on polylactic acid/polyglycolic acid (PLA/PGA) copolymer scaffolds being generated by rapid prototyping. The bone defects were then reconstructed by implanting these tissue-constructs into bone defects. The postoperative computerized topographic scans as well as the intraoperative sites demonstrated the accurate fit in the defect sites. The individual created, implanted scaffold constructs enriched with the porcine osteoblast-like cells were well tolerated and appeared to support bone formation, as revealed by immunohistochemical and histological analyses. The results of this investigations indicated that the in vitro expanded osteoblast-like cells spread on a resorbable individualized, computer-aided fabricated scaffold is capable of promoting the repair of bone tissue defects in vivo. The shown results warrant further attempts to combine computer modelling and tissue engineering for use in different ways in bone reconstructive surgery.

  17. Three-dimensional textures and defects of soft material layering revealed by thermal sublimation

    PubMed Central

    Yoon, Dong Ki; Kim, Yun Ho; Kim, Dae Seok; Oh, Seong Dae; Smalyukh, Ivan I.; Clark, Noel A.; Jung, Hee-Tae

    2013-01-01

    Layering is found and exploited in a variety of soft material systems, ranging from complex macromolecular self-assemblies to block copolymer and small-molecule liquid crystals. Because the control of layer structure is required for applications and characterization, and because defects reveal key features of the symmetries of layered phases, a variety of techniques have been developed for the study of soft-layer structure and defects, including X-ray diffraction and visualization using optical transmission and fluorescence confocal polarizing microscopy, atomic force microscopy, and SEM and transmission electron microscopy, including freeze-fracture transmission electron microscopy. Here, it is shown that thermal sublimation can be usefully combined with such techniques to enable visualization of the 3D structure of soft materials. Sequential sublimation removes material in a stepwise fashion, leaving a remnant layer structure largely unchanged and viewable using SEM, as demonstrated here using a lamellar smectic liquid crystal. PMID:24218602

  18. Waveguides based on linear defects in metal electromagnetic crystals

    NASA Astrophysics Data System (ADS)

    Vetluzhskii, A. Yu.

    2017-01-01

    Waveguides that represent linear defects in 2D metal photonic crystals are considered. Guiding properties of such structures at the frequencies of the first allowed band are demonstrated. The physical effect leading to the localization of radiation in defect area in the crystal is discussed.

  19. Defect-Induced Optoelectronic Response in Single-layer Group-VI Transition-Metal Dichalcogenides

    NASA Astrophysics Data System (ADS)

    Chow, Philippe K.

    The ever-evolving symbiosis between mankind and nanoelectronics-driven technology pushes the limits of its constituent materials, largely due to the dominance of undesirable hetero-interfacial physiochemical behavior at the few-nanometer length scale, which dominates over bulk material characteristics. Driven by such instabilities, research into two-dimensional (2D) van der Waals-layered materials (e.g. graphene, transition metal dichalcogenides (TMDCs), boron nitride), which have characteristically inert surface chemistry, has virtually exploded over the past few years. The discovery of an indirect- to direct-gap conversion in semiconducting group-VI TMDCs (e.g. MoS2) upon thinning to a single atomic layer provided the critical link between metallic and insulating 2D materials. While proof-of-concept demonstrations of single-layer TMDC-based devices for visible-range photodetection, light-emission and solar energy conversion have showed promising results, the exciting qualities are downplayed by poorly-understood defectinduced photocarrier traps, limiting the best-achieved external quantum efficiencies to approximately ~1%. This thesis explores the behavior of defects in atomically-thin TMDC layers in response to optical stimuli using a combination of steady-state photoluminescence, reflectance and Raman spectroscopy at room-temperature. By systematically varying the defect density using plasma-irradiation techniques, an unprecedented room-temperature defect-induced monolayer PL feature was discovered. High-resolution transmission electron microscopy correlated the defect-induced PL with plasma-generation of sulfur vacancy defects while reflectance measurements indicate defect-induced sub-bandgap light absorption. Excitation intensity-dependent PL measurements and exciton rate modeling further help elucidate the origin of the defect-induced PL response and highlights the role of non-radiative recombination on exciton conversion processes. The results in this

  20. General features

    SciTech Connect

    Wallace, R.E.

    1990-01-01

    The San Andreas fault system, a complex of faults that display predominantly large-scale strike slip, is part of an even more complex system of faults, isolated segments of the East Pacific Rise, and scraps of plates lying east of the East Pacific Rise that collectively separate the North American plate from the Pacific plate. This chapter briefly describes the San Andreas fault system, its setting along the Pacific Ocean margin of North America, its extent, and the patterns of faulting. Only selected characteristics are described, and many features are left for depictions on maps and figures.

  1. Regenerative Potential of Tissue-Engineered Nasal Chondrocytes in Goat Articular Cartilage Defects.

    PubMed

    Mumme, Marcus; Steinitz, Amir; Nuss, Katja M; Klein, Karina; Feliciano, Sandra; Kronen, Peter; Jakob, Marcel; von Rechenberg, Brigitte; Martin, Ivan; Barbero, Andrea; Pelttari, Karoliina

    2016-11-01

    Nasal chondrocytes (NC) were previously demonstrated to remain viable and to participate in the repair of articular cartilage defects in goats. Here, we investigated critical features of tissue-engineered grafts generated by NC in this large animal model, namely cell retention at the implantation site, architecture and integration with adjacent tissues, and effects on subchondral bone changes. In this study, isolated autologous goat NC (gNC) and goat articular chondrocytes (gAC, as control) were expanded, green fluorescent protein-labelled and seeded on a type I/III collagen membrane. After chondrogenic differentiation, tissue-engineered grafts were implanted into chondral defects (6 mm in diameter) in the stifle joint for 3 or 6 months. At the time of explantation, surrounding tissues showed no or very low (only in the infrapatellar fat pad <0.32%) migration of the grafted cells. In repair tissue, gNC formed typical structures of articular cartilage, such as flattened cells at the surface and column-like clusters in the middle layers. Semi-quantitative histological evaluation revealed efficient integration of the grafted tissues with the adjacent native cartilage and underlying subchondral bone. A significantly increased subchondral bone area, as a sign for the onset of osteoarthritis, was observed following treatment of cartilage defects with gAC-, but not with gNC-grafts. Our results reinforce the use of NC-based engineered tissue for articular cartilage repair and preliminarily indicate their potential for the treatment of early osteoarthritic defects.

  2. Quantum computing with defects.

    PubMed

    Weber, J R; Koehl, W F; Varley, J B; Janotti, A; Buckley, B B; Van de Walle, C G; Awschalom, D D

    2010-05-11

    Identifying and designing physical systems for use as qubits, the basic units of quantum information, are critical steps in the development of a quantum computer. Among the possibilities in the solid state, a defect in diamond known as the nitrogen-vacancy (NV(-1)) center stands out for its robustness--its quantum state can be initialized, manipulated, and measured with high fidelity at room temperature. Here we describe how to systematically identify other deep center defects with similar quantum-mechanical properties. We present a list of physical criteria that these centers and their hosts should meet and explain how these requirements can be used in conjunction with electronic structure theory to intelligently sort through candidate defect systems. To illustrate these points in detail, we compare electronic structure calculations of the NV(-1) center in diamond with those of several deep centers in 4H silicon carbide (SiC). We then discuss the proposed criteria for similar defects in other tetrahedrally coordinated semiconductors.

  3. Defect-induced loading of Pt nanoparticles on carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Kim, Sung Jin; Park, Yong Jin; Ra, Eun Ju; Kim, Ki Kang; An, Kay Hyeok; Lee, Young Hee; Choi, Jae Young; Park, Chan Ho; Doo, Seok Kwang; Park, Min Ho; Yang, Cheol Woong

    2007-01-01

    Carbon nanotubes-supported Pt nanoparticles were loaded using a microwave oven on the defective carbon nanotubes generated by an additional oxidant during acid treatment. The authors' Raman spectra and x-ray diffraction analysis demonstrated that defects created during oxidation and microwave treatment acted as nucleation seeds for Pt adsorption. The generated Pt nanoparticles had the size distributions of 2-3nm and were uniformly distributed on the defects of carbon nanotubes. The authors' density functional calculations showed that the adsorption of Pt atom on the vacancy of nanotube was significantly stronger by s-p hybridization with carbon atoms near the defect site.

  4. Internal defect inspection in magnetic tile by using acoustic resonance technology

    NASA Astrophysics Data System (ADS)

    Xie, Luofeng; Yin, Ming; Huang, Qinyuan; Zhao, Yue; Deng, Zhenbo; Xiang, Zhaowei; Yin, Guofu

    2016-11-01

    This paper focuses on the validity of a nondestructive methodology for magnetic tile internal defect inspection based on acoustic resonance. The principle of this methodology is to analyze the acoustic signal collected from the collision of magnetic tile with a metal block. To accomplish the detection process, the separating part of the detection system is designed and discussed in detail in this paper. A simplified mathematical model is constructed to analyze the characteristics of the impact of magnetic tile with a metal block. The results demonstrate that calculating the power spectrum density (PSD) can diagnose the internal defect of magnetic tile. Two different data-driven multivariate algorithms are adopted to obtain the feature set, namely principal component analysis (PCA) and hierarchical nonlinear principal component analysis (h-NLPCA). Three different classifiers are then performed to deal with magnetic tile classification problem based on features extracted by PCA or h-NLPCA. The classifiers adopted in this paper are fuzzy neural networks (FNN), variable predictive model based class discrimination (VPMCD) method and support vector machine (SVM). Experimental results show that all six methods are successful in identifying the magnetic tile internal defect. In this paper, the effect of environmental noise is also considered, and the classification results show that all the methods have high immunity to background noise, especially PCA-SVM and h-NLPCA-SVM. Considering the accuracy rate, computation cost problem and the ease of implementation, PCA-SVM turns out to be the best method for this purpose.

  5. Phase field crystal modeling as a unified atomistic approach to defect dynamics

    NASA Astrophysics Data System (ADS)

    Berry, Joel; Provatas, Nikolas; Rottler, Jörg; Sinclair, Chad W.

    2014-06-01

    Material properties controlled by evolving defect structures, such as mechanical response, often involve processes spanning many length and time scales which can not be modeled using a single approach. We present a variety of results that demonstrate the ability of phase field crystal (PFC) models to describe complex defect evolution phenomena on atomistic length scales and over long, diffusive time scales. Primary emphasis is given to the unification of conservative and nonconservative dislocation creation mechanisms in three-dimensional fcc and bcc materials. These include Frank-Read-type glide mechanisms involving closed dislocation loops or grain boundaries as well as Bardeen-Herring-type climb mechanisms involving precipitates, inclusions, and/or voids. Both source classes are naturally and simultaneously captured at the atomistic level by PFC descriptions, with arbitrarily complex defect configurations, types, and environments. An unexpected dipole-to-quadrupole source transformation is identified, as well as various complex geometrical features of loop nucleation via climb from spherical particles. Results for the strain required to nucleate a dislocation loop from such a particle are in agreement with analytic continuum theories. Other basic features of fcc and bcc dislocation structure and dynamics are also outlined, and initial results for dislocation-stacking fault tetrahedron interactions are presented. These findings together highlight various capabilities of the PFC approach as a coarse-grained atomistic tool for the study of three-dimensional crystal plasticity.

  6. Polarized Light Corridor Demonstrations.

    ERIC Educational Resources Information Center

    Davies, G. R.

    1990-01-01

    Eleven demonstrations of light polarization are presented. Each includes a brief description of the apparatus and the effect demonstrated. Illustrated are strain patterns, reflection, scattering, the Faraday Effect, interference, double refraction, the polarizing microscope, and optical activity. (CW)

  7. Overhead Projector Demonstrations.

    ERIC Educational Resources Information Center

    Kolb, Doris, Ed.

    1989-01-01

    Described are demonstrations of the optical activity of two sugar solutions, and the effects of various substituents on acid strength using an overhead projector. Materials and procedures for each demonstration are discussed. (CW)

  8. Mechanical Forces Exacerbate Periodontal Defects in Bsp-null Mice

    PubMed Central

    Soenjaya, Y.; Foster, B.L.; Nociti, F.H.; Ao, M.; Holdsworth, D.W.; Hunter, G.K.; Somerman, M.J.

    2015-01-01

    Bone sialoprotein (BSP) is an acidic phosphoprotein with collagen-binding, cell attachment, and hydroxyapatite-nucleating properties. BSP expression in mineralized tissues is upregulated at onset of mineralization. Bsp-null (Bsp-/-) mice exhibit reductions in bone mineral density, bone turnover, osteoclast activation, and impaired bone healing. Furthermore, Bsp-/- mice have marked periodontal tissue breakdown, with a lack of acellular cementum leading to periodontal ligament detachment, extensive alveolar bone and tooth root resorption, and incisor malocclusion. We hypothesized that altered mechanical stress from mastication contributes to periodontal destruction observed in Bsp-/- mice. This hypothesis was tested by comparing Bsp-/- and wild-type mice fed with standard hard pellet diet or soft powder diet. Dentoalveolar tissues were analyzed using histology and micro–computed tomography. By 8 wk of age, Bsp-/- mice exhibited molar and incisor malocclusion regardless of diet. Bsp-/- mice with hard pellet diet exhibited high incidence (30%) of severe incisor malocclusion, 10% lower body weight, 3% reduced femur length, and 30% elevated serum alkaline phosphatase activity compared to wild type. Soft powder diet reduced severe incisor malocclusion incidence to 3% in Bsp-/- mice, supporting the hypothesis that occlusal loading contributed to the malocclusion phenotype. Furthermore, Bsp-/- mice in the soft powder diet group featured normal body weight, long bone length, and serum alkaline phosphatase activity, suggesting that tooth dysfunction and malnutrition contribute to growth and skeletal defects reported in Bsp-/- mice. Bsp-/- incisors also erupt at a slower rate, which likely leads to the observed thickened dentin and enhanced mineralization of dentin and enamel toward the apical end. We propose that the decrease in eruption rate is due to a lack of acellular cementum and associated defective periodontal attachment. These data demonstrate the importance of BSP

  9. Mechanical Forces Exacerbate Periodontal Defects in Bsp-null Mice.

    PubMed

    Soenjaya, Y; Foster, B L; Nociti, F H; Ao, M; Holdsworth, D W; Hunter, G K; Somerman, M J; Goldberg, H A

    2015-09-01

    Bone sialoprotein (BSP) is an acidic phosphoprotein with collagen-binding, cell attachment, and hydroxyapatite-nucleating properties. BSP expression in mineralized tissues is upregulated at onset of mineralization. Bsp-null (Bsp(-/-)) mice exhibit reductions in bone mineral density, bone turnover, osteoclast activation, and impaired bone healing. Furthermore, Bsp(-/-) mice have marked periodontal tissue breakdown, with a lack of acellular cementum leading to periodontal ligament detachment, extensive alveolar bone and tooth root resorption, and incisor malocclusion. We hypothesized that altered mechanical stress from mastication contributes to periodontal destruction observed in Bsp(-/-) mice. This hypothesis was tested by comparing Bsp(-/-) and wild-type mice fed with standard hard pellet diet or soft powder diet. Dentoalveolar tissues were analyzed using histology and micro-computed tomography. By 8 wk of age, Bsp(-/-) mice exhibited molar and incisor malocclusion regardless of diet. Bsp(-/-) mice with hard pellet diet exhibited high incidence (30%) of severe incisor malocclusion, 10% lower body weight, 3% reduced femur length, and 30% elevated serum alkaline phosphatase activity compared to wild type. Soft powder diet reduced severe incisor malocclusion incidence to 3% in Bsp(-/-) mice, supporting the hypothesis that occlusal loading contributed to the malocclusion phenotype. Furthermore, Bsp(-/-) mice in the soft powder diet group featured normal body weight, long bone length, and serum alkaline phosphatase activity, suggesting that tooth dysfunction and malnutrition contribute to growth and skeletal defects reported in Bsp(-/-) mice. Bsp(-/-) incisors also erupt at a slower rate, which likely leads to the observed thickened dentin and enhanced mineralization of dentin and enamel toward the apical end. We propose that the decrease in eruption rate is due to a lack of acellular cementum and associated defective periodontal attachment. These data demonstrate the

  10. Overhead Projector Demonstrations.

    ERIC Educational Resources Information Center

    Kolb, Doris, Ed.

    1988-01-01

    Details two demonstrations for use with an overhead projector in a chemistry lecture. Includes "A Very Rapidly Growing Silicate Crystal" and "A Colorful Demonstration to Simulate Orbital Hybridization." The materials and directions for each demonstration are included as well as a brief explanation of the essential learning involved. (CW)

  11. Classroom Demonstrations: Individual Differences.

    ERIC Educational Resources Information Center

    Singer, Sandra M.

    These demonstrations stress individual differences, a concept becoming increasingly important in psychological research. Intended for use in undergraduate psychology courses, four demonstrations that illustrate common examples of human variation are described. The demonstrations deal with the following individual differences: taste blindness,…

  12. Adolescents' Demonstrative Behavior Research

    ERIC Educational Resources Information Center

    Parfilova, Gulfiya G.; Karimova, Lilia Sh.

    2016-01-01

    The problem of demonstrative behavior is very topical among teenagers and this issue has become the subject of systematic scientific research. Demonstrative manifestations in adolescents disrupt the favorable socialization; therefore, understanding, prevention and correction of demonstrative behavior at this age is relevant and requires special…

  13. A Boyle's Law Demonstrator.

    ERIC Educational Resources Information Center

    Sathe, Dileep V.

    1984-01-01

    The usual apparatus for demonstrating Boyle's law produces reasonably accurate results, but is not impressive as a demonstration because students cannot easily appreciate the change in pressure. An apparatus designed to produce a more effective demonstration is described. Procedures employed are also described. (JN)

  14. Classical Demonstration of Polarization.

    ERIC Educational Resources Information Center

    Bauman, Robert P.; Moore, Dennis R.

    1980-01-01

    Presents a classical demonstration of polarization for high school students. The initial state of this model, which demonstrates the important concepts of the optical and quantum problems, was developed during the 1973 summer program on lecture demonstration at the U.S. Naval Academy. (HM)

  15. Structural phase transitions and topological defects in ion Coulomb crystals

    SciTech Connect

    Partner, Heather L.; Nigmatullin, Ramil; Burgermeister, Tobias; Keller, Jonas; Pyka, Karsten; Plenio, Martin B.; Retzker, Alex; Zurek, Wojciech Hubert; del Campo, Adolfo; Mehlstaubler, Tanja E.

    2014-11-19

    We use laser-cooled ion Coulomb crystals in the well-controlled environment of a harmonic radiofrequency ion trap to investigate phase transitions and defect formation. Topological defects in ion Coulomb crystals (kinks) have been recently proposed for studies of nonlinear physics with solitons and as carriers of quantum information. Defects form when a symmetry breaking phase transition is crossed non-adiabatically. For a second order phase transition, the Kibble-Zurek mechanism predicts that the formation of these defects follows a power law scaling in the rate of the transition. We demonstrate a scaling of defect density and describe kink dynamics and stability. We further discuss the implementation of mass defects and electric fields as first steps toward controlled kink preparation and manipulation.

  16. Defect-induced supercollision cooling of photoexcited carriers in graphene.

    PubMed

    Alencar, Thonimar V; Silva, Mychel G; Malard, Leandro M; de Paula, Ana M

    2014-10-08

    Defects play a fundamental role in the energy relaxation of hot photoexcited carriers in graphene, thus a complete understanding of these processes are vital for improving the development of graphene devices. Recently, it has been theoretically predicted and experimentally demonstrated that defect-assisted acoustic phonon supercollision, the collision between a carrier and both an acoustic phonon and a defect, is an important energy relaxation process for carriers with excess energy below the optical phonon emission. Here, we studied samples with defects optically generated in a controlled manner to experimentally probe the supercollision model as a function of the defect density. We present pump and probe transient absorption measurements showing that the decay time decreases as the density of defect increases as predicted by the supercollision model.

  17. Experimental demonstration of topologically protected efficient sound propagation in an acoustic waveguide network

    NASA Astrophysics Data System (ADS)

    Wei, Qi; Tian, Ye; Zuo, Shu-Yu; Cheng, Ying; Liu, Xiao-Jun

    2017-03-01

    Acoustic topological states support sound propagation along the boundary in a one-way direction with inherent robustness against defects and disorders, leading to the revolution of the manipulation on acoustic waves. A variety of acoustic topological states relying on circulating fluid, chiral coupling, or temporal modulation have been proposed theoretically. However, experimental demonstration has so far remained a significant challenge, due to the critical limitations such as structural complexity and high losses. Here, we experimentally demonstrate an acoustic anomalous Floquet topological insulator in a waveguide network. The acoustic gapless edge states can be found in the band gap when the waveguides are strongly coupled. The scheme features simple structure and high-energy throughput, leading to the experimental demonstration of efficient and robust topologically protected sound propagation along the boundary. The proposal may offer a unique, promising application for design of acoustic devices in acoustic guiding, switching, isolating, filtering, etc.

  18. Edible Astronomy Demonstrations

    NASA Astrophysics Data System (ADS)

    Lubowich, D. A.

    2006-08-01

    By using astronomy demonstrations with edible ingredients, I have been able to increase student interest and knowledge of astronomical concepts. This approach has been successful with all age groups from elementary school through college students. I will present some of the edible demonstrations I have created including using popcorn to simulate radioactivity; using chocolate, nuts, and marshmallows to illustrate density and differentiation during the formation of the planets; and making big-bang brownies or chocolate chip-cookies to illustrate the expansion of the Universe. Sometimes the students eat the results of the astronomical demonstrations. These demonstrations are an effective teaching tool and the students remember these demonstrations after they are presented.

  19. Data surety demonstrations

    SciTech Connect

    Draelos, T.; Harris, M.; Herrington, P.; Kromer, D.

    1998-08-01

    The use of data surety within the International Monitoring System (IMS) is designed to offer increased trust of acquired sensor data at a low cost. The demonstrations discussed in the paper illustrate the feasibility of hardware authentication for sensor data and commands in a retrofit environment and a new system and of the supporting key management system. The individual demonstrations which are summarized in the paper are: (1) demonstration of hardware authentication for communication authentication in a retrofit environment; (2)demonstration of hardware authentication in a new system; and (3) demonstration of key management for sensor data and command authentication.

  20. Strategy Guideline: Demonstration Home

    SciTech Connect

    Savage, C.; Hunt, A.

    2012-12-01

    This guideline will provide a general overview of the different kinds of demonstration home projects, a basic understanding of the different roles and responsibilities involved in the successful completion of a demonstration home, and an introduction into some of the lessons learned from actual demonstration home projects. Also, this guideline will specifically look at the communication methods employed during demonstration home projects. And lastly, we will focus on how to best create a communication plan for including an energy efficient message in a demonstration home project and carry that message to successful completion.

  1. Strategy Guideline. Demonstration Home

    SciTech Connect

    Hunt, A.; Savage, C.

    2012-12-01

    This guideline will provide a general overview of the different kinds of demonstration home projects, a basic understanding of the different roles and responsibilities involved in the successful completion of a demonstration home, and an introduction into some of the lessons learned from actual demonstration home projects. Also, this guideline will specifically look at the communication methods employed during demonstration home projects. And lastly, we will focus on how to best create a communication plan for including an energy efficient message in a demonstration home project and carry that message to successful completion.

  2. Identification of surface defects on glass by parallel spectral domain optical coherence tomography.

    PubMed

    Chen, Zhiyan; Shen, Yi; Bao, Wen; Li, Peng; Wang, Xiaoping; Ding, Zhihua

    2015-09-07

    Defects can dramatically degrade glass quality, and automatic inspection is a trend of quality control in modern industry. One challenge in inspection in an uncontrolled environment is the misjudgment of fake defects (such as dust particles) as surface defects. Fortunately, optical changes within the periphery of a surface defect are usually introduced while those of a fake defect are not. The existence of changes within the defect peripheries can be adopted as a criterion for defect identification. However, modifications within defect peripheries can be too small to be noticeable in intensity based optical image of the glass surface, and misjudgments of modifications may occur due to the incorrectness in defect demarcation. Thus, a sensitive and reliable method for surface defect identification is demanded. To this end, a nondestructive method based on optical coherence tomography (OCT) is proposed to precisely demarcate surface defects and sensitively measure surface deformations. Suspected surface defects are demarcated using the algorithm based on complex difference from expectation. Modifications within peripheries of suspected surface defects are mapped by phase information from complex interface signal. In this way, surface defects are discriminated from fake defects using a parallel spectral domain OCT (SD-OCT) system. Both simulations and experiments are conducted, and these preliminary results demonstrate the advantage of the proposed method to identify glass surface defects.

  3. The emergence of defective predators who never hunt by themselves

    NASA Astrophysics Data System (ADS)

    Wang, Xueting; Pan, Qiuhui; Kang, Yibin; He, Mingfeng

    2013-06-01

    We propose a lattice Monte Carlo model of two populations, predators and prey. We divide predators into cooperative predators and defective predators. Cooperative predators participate in hunting. On the other hand, defective predators only participate to dominate, i.e. take possession of, the food when a kill has already been made by a cooperative predator. Numerous factors have been taken into account in our research, such as individual mobility, predation and hunger time. The model we have constructed displays the features of the population that evolve through time and the spatial distribution of the population. We focus on the emergence of defective predators and how the parameters affect the system. The results indicate that prey can profit from the appearance of these defective predators in some specific situations. It has even been shown that the emergence of defective predators can sometimes save endangered systems.

  4. Defects and Ion-Solid Interactions in Silicon Carbide

    SciTech Connect

    Weber, William J.; Gao, Fei; Devanathan, Ram; Jiang, Weilin; Zhang, Yanwen

    2005-01-03

    Atomic-level simulations are used to determine defect production, cascade-overlap effects, and defect migration energies in SiC. Energetic C and Si collision cascades primarily produce single interstitials, mono-vacancies, antisite defects, and small defect clusters, while amorphous clusters are produced within 25% of Au cascades. Cascade overlap results in defect stimulated cluster growth that produces amorphization. The good agreement of disordering behavior and changes in volume and elastic modulus obtained computationally and experimentally provides atomic-level interpretation of experimentally observed features. Simulations indicate that close-pair recombination activation energies range from 0.24 to 0.38 eV, and long-range migration energies for interstitials and vacancies have been determined.

  5. Orientational order of motile defects in active nematics

    SciTech Connect

    DeCamp, Stephen J.; Redner, Gabriel S.; Baskaran, Aparna; Hagan, Michael F.; Dogic, Zvonimir

    2015-08-17

    The study of equilibrium liquid crystals has led to fundamental insights into the nature of ordered materials, as well as many practical applications such as display technologies. Active nematics are a fundamentally different class of liquid crystals, which are driven away from equilibrium by the autonomous motion of their constituent rodlike particles. This internally-generated activity powers the continuous creation and annihilation of topological defects, leading to complex streaming flows whose chaotic dynamics appear to destroy long-range order. Here, we study these dynamics in experimental and computational realizations of active nematics. By tracking thousands of defects over centimeter distances in microtubule-based active nematics, we identify a non-equilibrium phase characterized by system-spanning orientational order of defects. This emergent order persists over hours despite defect lifetimes of only seconds. Lastly, similar dynamical structures are observed in coarse-grained simulations, suggesting that defect-ordered phases are a generic feature of active nematics.

  6. STM fingerprints of point defects in graphene: a theoretical prediction

    SciTech Connect

    Amara, Hakim; Latil, Sylvain; Meunier, Vincent; Lambin, Philippe; Charlier, Jean Christophe

    2007-01-01

    Scanning tunneling microscopy (STM) is one of the most appropriate techniques to investigate the atomic structure of carbon nanomaterials. However, the experimental identification of topological and nontopological modifications of the hexagonal network of sp{sup 2} carbon nanostructures remains a great challenge. The goal of the present theoretical work is to predict the typical electronic features of a few defects that are likely to occur in sp{sup 2} carbon nanostructures, such as atomic vacancy, divacancy, adatom, and Stone-Wales defect. The modifications induced by those defects in the electronic properties of the graphene sheet are investigated using first-principles calculations. In addition, computed constant-current STM images of these defects are calculated within a tight-binding approach in order to facilitate the interpretation of STM images of defected carbon nanostructures.

  7. Decision-Level Fusion of Spatially Scattered Multi-Modal Data for Nondestructive Inspection of Surface Defects

    PubMed Central

    Heideklang, René; Shokouhi, Parisa

    2016-01-01

    This article focuses on the fusion of flaw indications from multi-sensor nondestructive materials testing. Because each testing method makes use of a different physical principle, a multi-method approach has the potential of effectively differentiating actual defect indications from the many false alarms, thus enhancing detection reliability. In this study, we propose a new technique for aggregating scattered two- or three-dimensional sensory data. Using a density-based approach, the proposed method explicitly addresses localization uncertainties such as registration errors. This feature marks one of the major of advantages of this approach over pixel-based image fusion techniques. We provide guidelines on how to set all the key parameters and demonstrate the technique’s robustness. Finally, we apply our fusion approach to experimental data and demonstrate its capability to locate small defects by substantially reducing false alarms under conditions where no single-sensor method is adequate. PMID:26784200

  8. Atrial Septal Defect (For Parents)

    MedlinePlus

    ... Defect Preparing Your Child for Surgery Heart and Circulatory System Anesthesia Basics Congenital Heart Defects Activity: The Heart ... EKG (Video) Going to the Hospital Your Heart & Circulatory System Quiz: Heart & Circulatory System EKG (Video) What's It ...

  9. Atrial Septal Defect (For Kids)

    MedlinePlus

    ... Dictionary of Medical Words En Español What Other Kids Are Reading Taking Care of Your Ears Taking ... an X-ray Atrial Septal Defect KidsHealth > For Kids > Atrial Septal Defect Print A A A What's ...

  10. Congenital heart defect - corrective surgery

    MedlinePlus

    ... repair; Tetralogy of Fallot repair; Coarctation of the aorta repair; Atrial septal defect repair; Ventricular septal defect ... the pulmonary valve and removing the thickened muscle (stenosis). Placing a patch on the right ventricle and ...

  11. Neural tube defects.

    PubMed

    Greene, Nicholas D E; Copp, Andrew J

    2014-01-01

    Neural tube defects (NTDs), including spina bifida and anencephaly, are severe birth defects of the central nervous system that originate during embryonic development when the neural tube fails to close completely. Human NTDs are multifactorial, with contributions from both genetic and environmental factors. The genetic basis is not yet well understood, but several nongenetic risk factors have been identified as have possibilities for prevention by maternal folic acid supplementation. Mechanisms underlying neural tube closure and NTDs may be informed by experimental models, which have revealed numerous genes whose abnormal function causes NTDs and have provided details of critical cellular and morphological events whose regulation is essential for closure. Such models also provide an opportunity to investigate potential risk factors and to develop novel preventive therapies.

  12. A method of gear defect intelligent detection based on transmission noise

    NASA Astrophysics Data System (ADS)

    Chen, Hong-fang; Zhao, Yun; Lin, Jia-chun; Guo, Mian

    2015-02-01

    A new approach was proposed by combing Ensemble Empirical Mode Decomposition (EEMD) algorithm and Back Propagation (BP) neural network for detection of gear through transmission noise analysis. Then feature values of the feature signals are calculated. The feature values which have a great difference for different defect types are chosen to build an eigenvector. BP neural network is used to train and learn on the eigenvector for recognition of gear defects intelligently. In this study, a comparative experiment has been performed among normal gears, cracked gears and eccentric gears with fifteen sets of different gears. Experimental results indicate that the proposed method can detect gear defect features carried by the transmission noise effectively.

  13. Controversies in Parotid Defect Reconstruction.

    PubMed

    Tamplen, Matthew; Knott, P Daniel; Fritz, Michael A; Seth, Rahul

    2016-08-01

    Reconstruction of the parotid defect is a complex topic that encompasses restoration of both facial form and function. The reconstructive surgeon must consider facial contour, avoidance of Frey syndrome, skin coverage, tumor surveillance, potential adjuvant therapy, and facial reanimation when addressing parotid defects. With each defect there are several options within the reconstructive ladder, creating controversies regarding optimal management. This article describes surgical approaches to reconstruction of parotid defects, highlighting areas of controversy.

  14. Molecular defects in the chondrodysplasias

    SciTech Connect

    Rimoin, D.L.

    1996-05-03

    There has been a recent explosion of knowledge concerning the biochemical and molecular defects in the skeletal dysplasia. Through both the candidate gene approach and positional cloning, specific gene defects that produce the skeletal dysplasia have been identified and may be classified into several general categories: (1) qualitative or quantitative abnormalities in the structural proteins of cartilage; (2) inborn errors of cartilage metabolism; (3) defects in local regulators of cartilage growth; and (4) systemic defects influencing cartilage development. 35 refs., 1 tab.

  15. In-Process Detection of Weld Defects Using Laser-Based Ultrasonic Lamb Waves

    SciTech Connect

    Kercel, S W

    2001-01-04

    Laser-based ultrasonic (LBU) measurement shows great promise for on-line monitoring of weld quality in tailor-welded blanks. Tailor-welded blanks are steel blanks made from plates of differing thickness and/or properties butt-welded together; they are used in automobile manufacturing to produce body, frame, and closure panels. LBU uses a pulsed laser to generate the ultrasound and a continuous wave (CW) laser interferometer to detect the ultrasound at the point of interrogation to perform ultrasonic inspection. LBU enables in-process measurements since there is no sensor contact or near-contact with the workpiece. The authors have used laser-generated plate (Lamb) waves to propagate from one plate into the weld nugget as a means of detecting defects. This report recounts an investigation of a number of inspection architectures based on processing of signals from selected plate waves, which are either reflected from or transmitted through the weld zone. Bayesian parameter estimation and wavelet analysis (both continuous and discrete) have shown that the LBU time-series signal is readily separable into components that provide distinguishing features, which describe weld quality. The authors anticipate that, in an on-line industrial application, these measurements can be implemented just downstream from the weld cell. Then the weld quality data can be fed back to control critical weld parameters or alert the operator of a problem requiring maintenance. Internal weld defects and deviations from the desired surface profile can then be corrected before defective parts are produced. The major conclusions of this study are as follows. Bayesian parameter estimation is able to separate entangled Lamb wave modes. Pattern recognition algorithms applied to Lamb mode features have produced robust features for distinguishing between several types of weld defects. In other words, the information is present in the output of the laser ultrasonic hardware, and it is feasible to

  16. Composite Defect Significance.

    DTIC Science & Technology

    1982-07-13

    A12i 299 COMPOSITE DEFECT SIGNIFICANCE(U) MATERIALS SCIENCES 1/1 \\ CORP SPRING HOUSE PA S N CHATTERJEE ET AL. 13 JUL 82 MSC/TFR/1288/il87 NADC-80848...Directorate 30 Sensors & Avionics Technology Directorate 40 Communication & Navigation Technology Directorate 50 Software Computer Directorate 60 Aircraft ...instructions concerning commercial products herein do not constitute an endorsement by the Government nor do they convey or imply the license or right to use

  17. Photonic defect modes in a cholesteric liquid crystal with a resonant nanocomposite layer and a twist defect

    NASA Astrophysics Data System (ADS)

    Vetrov, Stepan Ya.; Pyatnov, Maxim V.; Timofeev, Ivan V.

    2014-09-01

    We have studied spectral properties of a cholesteric liquid crystal with a combined defect consisting of a nanocomposite layer and a twist. The nanocomposite layer is made of metallic nanoballs dispersed in a transparent matrix and featuring effective resonant permittivity. A solution has been found for the transmission spectrum of circularly polarized waves in the structure. We have analyzed spectral splitting of the defect mode in the band gap of the cholesteric when its frequency coincides with the nanocomposite resonant frequency. Defect modes have characteristics strongly dependent on the magnitude and the sign of the phase difference of the cholesteric helix on both sides of the defect layer. It has been found that the band gap width and the position and localization degree of defect modes can be effectively controlled by external fields applied to the cholesteric.

  18. Photonic defect modes in a cholesteric liquid crystal with a resonant nanocomposite layer and a twist defect.

    PubMed

    Vetrov, Stepan Ya; Pyatnov, Maxim V; Timofeev, Ivan V

    2014-09-01

    We have studied spectral properties of a cholesteric liquid crystal with a combined defect consisting of a nanocomposite layer and a twist. The nanocomposite layer is made of metallic nanoballs dispersed in a transparent matrix and featuring effective resonant permittivity. A solution has been found for the transmission spectrum of circularly polarized waves in the structure. We have analyzed spectral splitting of the defect mode in the band gap of the cholesteric when its frequency coincides with the nanocomposite resonant frequency. Defect modes have characteristics strongly dependent on the magnitude and the sign of the phase difference of the cholesteric helix on both sides of the defect layer. It has been found that the band gap width and the position and localization degree of defect modes can be effectively controlled by external fields applied to the cholesteric.

  19. Fetal Valproate Syndrome with Limb Defects: An Indian Case Report

    PubMed Central

    Gupta, Ashok; Sharma, Manish; Mathur, Priyanshu; Bansal, Naresh

    2016-01-01

    Epilepsy is a common disorder and exposure to antiepileptic drugs during pregnancy increases the risk of teratogenicity. Older AEDs such as valproate and phenobarbital are associated with a higher risk of major malformations in the fetus than newer AEDs like lamotrigine and levetiracetam. Exposure to valproic acid during first trimester can result in fetal valproate syndrome (FVS), comprising typical facial features, developmental delay, and a variety of malformations such as neural tube defects, cardiac and genitourinary malformations, and limb defects. We are presenting an Indian case of FVS with major limb defects. PMID:28003925

  20. Defect mapping system

    DOEpatents

    Sopori, Bhushan L.

    1995-01-01

    Apparatus for detecting and mapping defects in the surfaces of polycrystalline materials in a manner that distinguishes dislocation pits from grain boundaries includes a laser for illuminating a wide spot on the surface of the material, a light integrating sphere with apertures for capturing light scattered by etched dislocation pits in an intermediate range away from specular reflection while allowing light scattered by etched grain boundaries in a near range from specular reflection to pass through, and optical detection devices for detecting and measuring intensities of the respective intermediate scattered light and near specular scattered light. A center blocking aperture or filter can be used to screen out specular reflected light, which would be reflected by nondefect portions of the polycrystalline material surface. An X-Y translation stage for mounting the polycrystalline material and signal processing and computer equipment accommodate rastor mapping, recording, and displaying of respective dislocation and grain boundary defect densities. A special etch procedure is included, which prepares the polycrystalline material surface to produce distinguishable intermediate and near specular light scattering in patterns that have statistical relevance to the dislocation and grain boundary defect densities.

  1. Defect mapping system

    DOEpatents

    Sopori, B.L.

    1995-04-11

    Apparatus for detecting and mapping defects in the surfaces of polycrystalline materials in a manner that distinguishes dislocation pits from grain boundaries includes a laser for illuminating a wide spot on the surface of the material, a light integrating sphere with apertures for capturing light scattered by etched dislocation pits in an intermediate range away from specular reflection while allowing light scattered by etched grain boundaries in a near range from specular reflection to pass through, and optical detection devices for detecting and measuring intensities of the respective intermediate scattered light and near specular scattered light. A center blocking aperture or filter can be used to screen out specular reflected light, which would be reflected by nondefect portions of the polycrystalline material surface. An X-Y translation stage for mounting the polycrystalline material and signal processing and computer equipment accommodate rastor mapping, recording, and displaying of respective dislocation and grain boundary defect densities. A special etch procedure is included, which prepares the polycrystalline material surface to produce distinguishable intermediate and near specular light scattering in patterns that have statistical relevance to the dislocation and grain boundary defect densities. 20 figures.

  2. Pattern of congenital heart diseases in Rwandan children with genetic defects

    PubMed Central

    Teteli, Raissa; Uwineza, Annette; Butera, Yvan; Hitayezu, Janvier; Murorunkwere, Seraphine; Umurerwa, Lamberte; Ndinkabandi, Janvier; Hellin, Anne-Cécile; Jamar, Mauricette; Caberg, Jean-Hubert; Muganga, Narcisse; Mucumbitsi, Joseph; Rusingiza, Emmanuel Kamanzi; Mutesa, Leon

    2014-01-01

    Introduction Congenital heart diseases (CHD) are commonly associated with genetic defects. Our study aimed at determining the occurrence and pattern of CHD association with genetic defects among pediatric patients in Rwanda. Methods A total of 125 patients with clinical features suggestive of genetic defects were recruited. Echocardiography and standard karyotype studies were performed in all patients. Results CHDs were detected in the majority of patients with genetic defects. The commonest isolated CHD was ventricular septal defect found in many cases of Down syndrome. In total, chromosomal abnormalities represented the majority of cases in our cohort and were associated with various types of CHDs. Conclusion Our findings showed that CHDs are common in Rwandan pediatric patients with genetic defects. These results suggest that a routine echocardiography assessment combined with systematic genetic investigations including standard karyotype should be mandatory in patients presenting characteristic clinical features in whom CHD is suspected to be associated with genetic defect. PMID:25722758

  3. Demonstrating Bacterial Flagella.

    ERIC Educational Resources Information Center

    Porter, John R.; And Others

    1992-01-01

    Describes an effective laboratory method for demonstrating bacterial flagella that utilizes the Proteus mirabilis organism and a special harvesting technique. Includes safety considerations for the laboratory exercise. (MDH)

  4. Exploration Technology Development & Demonstration

    NASA Video Gallery

    Chris Moore delivers a presentation from the Exploration Technology Development & Demonstration (ETDD) study team on May 25, 2010, at the NASA Exploration Enterprise Workshop held in Galveston, TX....

  5. Study of lattice defect vibration

    NASA Technical Reports Server (NTRS)

    Elliott, R. J.

    1969-01-01

    Report on the vibrations of defects in crystals relates how defects, well localized in a crystal but interacting strongly with the other atoms, change the properties of a perfect crystal. The methods used to solve defect problems relate the properties of an imperfect lattice to the properties of a perfect lattice.

  6. Tested Demonstrations: Spectroscopy Illustrated.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1983-01-01

    Background information and procedures are provided for an experiment to prepare three metal derivatives of dimethyl sulfoxide (DMSO) and to determine some structural features of these derivatives based on their infrared spectra. Results and discussion of reactions involved are also provided. (JN)

  7. A Greener Chemiluminescence Demonstration

    ERIC Educational Resources Information Center

    Jilani, Osman; Donahue, Trisha M.; Mitchell, Miguel O.

    2011-01-01

    Because they are dramatic and intriguing, chemiluminescence demonstrations have been used for decades to stimulate interest in chemistry. One of the most intense chemiluminescent reactions is the oxidation of diaryl oxalate diesters with hydrogen peroxide in the presence of a fluorescer. In typical lecture demonstrations, the commercially…

  8. Levitation Kits Demonstrate Superconductivity.

    ERIC Educational Resources Information Center

    Worthy, Ward

    1987-01-01

    Describes the "Project 1-2-3" levitation kit used to demonstrate superconductivity. Summarizes the materials included in the kit. Discusses the effect demonstrated and gives details on how to obtain kits. Gives an overview of the documentation that is included. (CW)

  9. Demonstrating Newton's Second Law.

    ERIC Educational Resources Information Center

    Fricker, H. S.

    1994-01-01

    Describes an apparatus for demonstrating the second law of motion. Provides sample data and discusses the merits of this method over traditional methods of supplying a constant force. The method produces empirical best-fit lines which convincingly demonstrate that for a fixed mass, acceleration is proportional to force. (DDR)

  10. Demonstrating Phase Changes.

    ERIC Educational Resources Information Center

    Rohr, Walter

    1995-01-01

    Presents two experiments that demonstrate phase changes. The first experiment explores phase changes of carbon dioxide using powdered dry ice sealed in a piece of clear plastic tubing. The second experiment demonstrates an equilibrium process in which a crystal grows in equilibrium with its saturated solution. (PVD)

  11. USFWS demonstration fees

    USGS Publications Warehouse

    Taylor, Jonathan; Vaske, Jerry; Donnelly, Maureen; Shelby, Lori

    2002-01-01

    This study examined National Wildlife Refuge (NWR) visitors' reactions to changes in fees implemented as part of the fee demonstration program. Visitors' evaluations of the fees paid were examined in addition to their beliefs about fees and the fee demonstration program, and the impact of fees paid on their intention to return. All results were analyzed relative to socio-demographic characteristics.

  12. A Stellar Demonstrator

    ERIC Educational Resources Information Center

    Ros, Rosa M.

    2009-01-01

    The main purpose of the stellar demonstrator is to help explain the movement of stars. In particular, students have difficulties understanding why, if they are living in the Northern Hemisphere, they may observe starts in the Southern Hemisphere, or why circumpolar stars are not the same in different parts of Europe. Using the demonstrator, these…

  13. Kinetics and Catalysis Demonstrations.

    ERIC Educational Resources Information Center

    Falconer, John L.; Britten, Jerald A.

    1984-01-01

    Eleven videotaped kinetics and catalysis demonstrations are described. Demonstrations include the clock reaction, oscillating reaction, hydrogen oxidation in air, hydrogen-oxygen explosion, acid-base properties of solids, high- and low-temperature zeolite reactivity, copper catalysis of ammonia oxidation and sodium peroxide decomposition, ammonia…

  14. Better Ira Remsen Demonstration

    ERIC Educational Resources Information Center

    Dalby, David K.; Maynard, James H.; Moore, John W.

    2011-01-01

    Many versions of the classic Ira Remsen experience involving copper and concentrated nitric acid have been used as lecture demonstrations. Remsen's original reminiscence from 150 years ago is included in the Supporting Information, and his biography can be found on the Internet. This article presents a new version that makes the demonstration more…

  15. Demonstrating Reduced Gravity

    NASA Technical Reports Server (NTRS)

    Pearlman, Howard; Stocker, Dennis; Gotti, Daniel; Urban, David; Ross, Howard; Sours, Thomas

    1996-01-01

    A miniature drop tower, Reduced-Gravity Demonstrator is developed to illustrate the effects of gravity on a variety of phenomena including the way fluids flow, flames burn, and mechanical systems (such as pendulum) behave. A schematic and description of the demonstrator and payloads are given, followed by suggestions for how one can build his (her) own.

  16. INTERSTELLAR ANALOGS FROM DEFECTIVE CARBON NANOSTRUCTURES ACCOUNT FOR INTERSTELLAR EXTINCTION

    SciTech Connect

    Tan, Zhenquan; Abe, Hiroya; Sato, Kazuyoshi; Ohara, Satoshi; Chihara, Hiroki; Koike, Chiyoe; Kaneko, Kenji

    2010-11-15

    Because interstellar dust is closely related to the evolution of matter in the galactic environment and many other astrophysical phenomena, the laboratory synthesis of interstellar dust analogs has received significant attention over the past decade. To simulate the ultraviolet (UV) interstellar extinction feature at 217.5 nm originating from carbonaceous interstellar dust, many reports focused on the UV absorption properties of laboratory-synthesized interstellar dust analogs. However, no general relation has been established between UV interstellar extinction and artificial interstellar dust analogs. Here, we show that defective carbon nanostructures prepared by high-energy collisions exhibit a UV absorption feature at 220 nm which we suggest accounts for the UV interstellar extinction at 217.5 nm. The morphology of some carbon nanostructures is similar to that of nanocarbons discovered in the Allende meteorite. The similarity between the absorption feature of the defective carbon nanostructures and UV interstellar extinction indicates a strong correlation between the defective carbon nanostructures and interstellar dust.

  17. The Kinetics of Dislocation Loop Formation in Ferritic Alloys Through the Aggregation of Irradiation Induced Defects

    NASA Astrophysics Data System (ADS)

    Kohnert, Aaron Anthony

    The mechanical properties of materials are often degraded over time by exposure to irradiation environments, a phenomenon that has hindered the development of multiple nuclear reactor design concepts. Such property changes are the result of microstructural changes induced by the collision of high energy particles with the atoms in a material. The lattice defects generated in these recoil events migrate and interact to form extended damage structures. This study has used theoretical models based on the mean field chemical reaction rate theory to analyze the aggregation of isolated lattice defects into larger microstructural features that are responsible for long term property changes, focusing on the development of black dot damage in ferritic iron based alloys. The purpose of such endeavors is two-fold. Primarily, such models explain and quantify the processes through which these microstructures form. Additionally, models provide insight into the behavior and properties of the point defects and defect clusters which drive general microstructural evolution processes. The modeling effort presented in this work has focused on physical fidelity, drawing from a variety of sources of information to characterize the unobservable defect generation and agglomeration processes that give rise to the observable features reported in experimental data. As such, the models are based not solely on isolated point defect creation, as is the case with many older rate theory approaches, but instead on realistic estimates of the defect cluster population produced in high energy cascade damage events. Experimental assessments of the microstructural changes evident in transmission electron microscopy studies provide a means to measure the efficacy of the kinetic models. Using common assumptions of the mobility of defect clusters generated in cascade damage conditions, an unphysically high density of damage features develops at the temperatures of interest with a temperature dependence

  18. Image feature localization by multiple hypothesis testing of Gabor features.

    PubMed

    Ilonen, Jarmo; Kamarainen, Joni-Kristian; Paalanen, Pekka; Hamouz, Miroslav; Kittler, Josef; Kälviäinen, Heikki

    2008-03-01

    Several novel and particularly successful object and object category detection and recognition methods based on image features, local descriptions of object appearance, have recently been proposed. The methods are based on a localization of image features and a spatial constellation search over the localized features. The accuracy and reliability of the methods depend on the success of both tasks: image feature localization and spatial constellation model search. In this paper, we present an improved algorithm for image feature localization. The method is based on complex-valued multi resolution Gabor features and their ranking using multiple hypothesis testing. The algorithm provides very accurate local image features over arbitrary scale and rotation. We discuss in detail issues such as selection of filter parameters, confidence measure, and the magnitude versus complex representation, and show on a large test sample how these influence the performance. The versatility and accuracy of the method is demonstrated on two profoundly different challenging problems (faces and license plates).

  19. Thermal properties of defective fullerene

    NASA Astrophysics Data System (ADS)

    Li, Jian; Zheng, Dong-Qin; Zhong, Wei-Rong

    2016-09-01

    We have investigated the thermal conductivity of defective fullerene (C60) by using the nonequilibrium molecular dynamics (MD) method. It is found that the thermal conductivity of C60 with one defect is lower than the thermal conductivity of perfect C60. However, double defects in C60 have either positive or negative influence on the thermal conductivity, which depends on the positions of the defects. The phonon spectra of perfect and defective C60 are also provided to give corresponding supports. Our results can be extended to long C60 chains, which is helpful for the thermal management of C60.

  20. Understanding of Defect Physics in Polycrystalline Photovoltaic Materials: Preprint

    SciTech Connect

    Yan, Y.

    2011-07-01

    The performance of thin-film solar cells is influenced by the quality of interfaces and formation of defects such as point defects, stacking faults, twins, dislocations, and grain boundaries. It is important to understand the defect physics so that appropriate methods may be developed to suppress the formation of harmful defects. Here, we review our understanding of defect physics in thin-film photovoltaic (PV) materials such as Si, CdTe, Cu(In,Ga)Se2 (CIGS), Cu2ZnSnSe2 (CZTSe), and Cu2ZnSnS2 (CZTS) using the combination of nanoscale electron microscopy characterization and density-functional theory (DFT). Although these thin-film PV materials share the same basic structural feature - diamond structure based - the defect physics in them could be very different. Some defects, such as stacking faults and special twins, have similar electronic properties in these thin-film materials. However, some other defects, such as grain boundaries and interfaces, have very different electronic properties in these materials. For example, grain boundaries produce harmful deep levels in Si and CdTe, but they do not produce significant deep levels in CIGS, CZTSe, and CZTS. These explain why passivation is critical for Si and CdTe solar cells, but is less important in CIS and CZTS solar cells. We further provide understanding of the effects of interfaces on the performance of solar cells made of these PV materials.

  1. Defect detection for end surface of ferrite magnetic tile

    NASA Astrophysics Data System (ADS)

    Tao, Jiayuan; Wang, Yuwei; Wang, Keyi

    2016-09-01

    A visual automatic detection method is proposed for defect detection on end surface of ferrite magnetic tile to tackle the disadvantages generated by human work which has low efficiency and unstable accuracy. Because the defects on end surface of ferrite magnetic tile with dark colors and low contrasts are negative for defect detection, uniform illumination is provided by LED light source and a dedicated optical system is designed to extract defects conveniently. The approach uses comparison of the fitting and actual edge curves to detect defects mainly with most defects located on the edge. Firstly improved adaptive median filter is used as the image preprocessing. Subsequently the appropriate threshold is calculated by Otsu algorithm based on the extreme points in the gray-level histogram to segment the preprocessing image. Then the Sobel operator can be used to extract the edge of end surface precisely. Finally through comparing the ideal fitting and actual edge curves of end surface, to detect the defects with some relevant features. Experimental results show that the proposed scheme could detect defects on the end surface of ferrite magnetic tile efficiency and accurately with 93.33% accuracy rate, 2.30% false acceptance rate and 8.45% correct rejection rate.

  2. Defect-induced magnetism in neutron irradiated 6H-SiC single crystals.

    PubMed

    Liu, Yu; Wang, Gang; Wang, Shunchong; Yang, Jianhui; Chen, Liang; Qin, Xiubo; Song, Bo; Wang, Baoyi; Chen, Xiaolong

    2011-02-25

    Defect-induced magnetism is firstly observed in neutron irradiated SiC single crystals. We demonstrated that the intentionally created defects dominated by divacancies (V(Si)V(C)) are responsible for the observed magnetism. First-principles calculations revealed that defect states favor the formation of local moments and the extended tails of defect wave functions make long-range spin couplings possible. Our results confirm the existence of defect-induced magnetism, implying the possibility of tuning the magnetism of wide band-gap semiconductors by defect engineering.

  3. High Defect Tolerance in Lead Halide Perovskite CsPbBr3.

    PubMed

    Kang, Jun; Wang, Lin-Wang

    2017-01-19

    The formation energies and charge-transition levels of intrinsic point defects in lead halide perovskite CsPbBr3 are studied from first-principles calculations. It is shown that the formation energy of dominant defect under Br-rich growth condition is much lower than that under moderate or Br-poor conditions. Thus avoiding the Br-rich condition can help to reduce the defect concentration. Interestingly, CsPbBr3 is found to be highly defect-tolerant in terms of its electronic structure. Most of the intrinsic defects induce shallow transition levels. Only a few defects with high formation energies can create deep transition levels. Therefore, CsPbBr3 can maintain its good electronic quality despite the presence of defects. Such defect tolerance feature can be attributed to the lacking of bonding-antibonding interaction between the conduction bands and valence bands.

  4. METCAN demonstration manual, version 1.0

    NASA Technical Reports Server (NTRS)

    Lee, H.-J.; Murthy, P. L. N.

    1992-01-01

    The various features of the Metal Matrix Composite Analyzer (METCAN) computer program to simulate the high temperature nonlinear behavior of continuous fiber reinforced metal matrix composites are demonstrated. Different problems are used to demonstrate various capabilities of METCAN for both static and cyclic analyses. A complete description of the METCAN output file is also included to help interpret results.

  5. Experimental Demonstrations in Teaching Chemical Reactions.

    ERIC Educational Resources Information Center

    Hugerat, Muhamad; Basheer, Sobhi

    2001-01-01

    Presents demonstrations of chemical reactions by employing different features of various compounds that can be altered after a chemical change occurs. Experimental activities include para- and dia-magnetism in chemical reactions, aluminum reaction with base, reaction of acid with carbonates, use of electrochemical cells for demonstrating chemical…

  6. Pulsed infrared thermography processing and defects edge detection using FCA and ACA

    NASA Astrophysics Data System (ADS)

    Yuanlin, Liu; Qingju, Tang; Chiwu, Bu; Chen, Mei; Pingshan, Wang; Jiansuo, Zang

    2015-09-01

    CFRP sheet with delamination defects was detected using pulsed infrared thermography. The principle of polynomial fitting the derivative time algorithm (FDA) and related coefficient algorithm (RCA) was described. A new polynomial fitting the derivative time-related coefficient algorithm (FCA) was formed by combining FDA and RCA, which improves the signal to noise (SNR) of feature images, and is benefit for the detection and identification of defects. The defects edge identification procedure using ant colony algorithm (ACA) is given, and the defect edge features in the infrared image have been extracted using ACA effectively.

  7. Skin barrier defects in atopic dermatitis.

    PubMed

    Agrawal, Rachana; Woodfolk, Judith A

    2014-05-01

    Atopic dermatitis (AD) is a chronic inflammatory skin condition with complex etiology that is dependent upon interactions between the host and the environment. Acute skin lesions exhibit the features of a Th2-driven inflammatory disorder, and many patients are highly atopic. The skin barrier plays key roles in immune surveillance and homeostasis, and in preventing penetration of microbial products and allergens. Defects that compromise the structural integrity or else the immune function of the skin barrier play a pivotal role in the pathogenesis of AD. This article provides an overview of the array of molecular building blocks that are essential to maintaining healthy skin. The basis for structural defects in the skin is discussed in relation to AD, with an emphasis on filaggrin and its genetic underpinnings. Aspects of innate immunity, including the role of antimicrobial peptides and proteases, are also discussed.

  8. Demonstration of Surface Tension.

    ERIC Educational Resources Information Center

    Rosenthal, Andrew J.

    2001-01-01

    Surface tension is a fundamental obstacle in the spontaneous formation of bubbles, droplets, and crystal nuclei in liquids. Describes a simple overhead projector demonstration that illustrates the power of surface tension that can prevent so many industrial processes. (ASK)

  9. Demonstrating Natural Selection

    ERIC Educational Resources Information Center

    Hinds, David S.; Amundson, John C.

    1975-01-01

    Describes laboratory exercises with chickens selecting their food from dyed and natural corn kernels as a method of demonstrating natural selection. The procedure is based on the fact that organisms that blend into their surroundings escape predation. (BR)

  10. Floating Magnet Demonstration.

    ERIC Educational Resources Information Center

    Wake, Masayoshi

    1990-01-01

    A room-temperature demonstration of a floating magnet using a high-temperature superconductor is described. The setup and operation of the apparatus are described. The technical details of the effect are discussed. (CW)

  11. Overhead Projector Demonstrations.

    ERIC Educational Resources Information Center

    Hambly, Gordon F.; Goldsmith, Robert H.

    1988-01-01

    Presented is a method of demonstrating the optical activity of glucose using an overhead projector and easily obtainable materials. Explores the difference between reflected and transmitted light (Tyndall Effect) using sodium thiosulfate, hydrochloric acid, and an overhead projector. (ML)

  12. EVA Retriever Demonstration

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The EVA retriever is demonstrated in the Manipulator Development Facility (MDF). The retriever moves on the air bearing table 'searching' for its target, in this case tools 'dropped' by astronauts on orbit.

  13. Spacecraft servicing demonstration plan

    NASA Technical Reports Server (NTRS)

    Bergonz, F. H.; Bulboaca, M. A.; Derocher, W. L., Jr.

    1984-01-01

    A preliminary spacecraft servicing demonstration plan is prepared which leads to a fully verified operational on-orbit servicing system based on the module exchange, refueling, and resupply technologies. The resulting system can be applied at the space station, in low Earth orbit with an orbital maneuvering vehicle (OMV), or be carried with an OMV to geosynchronous orbit by an orbital transfer vehicle. The three phase plan includes ground demonstrations, cargo bay demonstrations, and free flight verifications. The plan emphasizes the exchange of multimission modular spacecraft (MMS) modules which involves space repairable satellites. Three servicer mechanism configurations are the engineering test unit, a protoflight quality unit, and two fully operational units that have been qualified and documented for use in free flight verification activity. The plan balances costs and risks by overlapping study phases, utilizing existing equipment for ground demonstrations, maximizing use of existing MMS equipment, and rental of a spacecraft bus.

  14. Classroom Demonstration of Sunspots.

    ERIC Educational Resources Information Center

    Callaway, Thomas O.; And Others

    1982-01-01

    An overhead projector, projection screen, and clear tungsten Filament light bulb operated through a dimmer or variac switch are used to demonstrate the fact that black appearance of sunspots is due only to contrast and that sunspots are bright. (SK)

  15. Technology Demonstration Missions

    NASA Video Gallery

    NASA's Technology Demonstration Missions (TDM) Program seeks to infuse new technology into space applications, bridging the gap between mature “lab-proven” technology and "flight-ready" status....

  16. Methanol Cannon Demonstrations Revisited.

    ERIC Educational Resources Information Center

    Dolson, David A.; And Others

    1995-01-01

    Describes two variations on the traditional methanol cannon demonstration. The first variation is a chain reaction using real metal chains. The second example involves using easily available components to produce sequential explosions that can be musical in nature. (AIM)

  17. Flagship Technology Demonstrations (FTD)

    NASA Video Gallery

    Mike Conley delivers a presentation from the Flagship Technology Demonstrations (FTD) study team on May 25, 2010, at the NASA Exploration Enterprise Workshop held in Galveston, TX. The purpose of t...

  18. Education Payload Operation - Demonstrations

    NASA Technical Reports Server (NTRS)

    Keil, Matthew

    2009-01-01

    Education Payload Operation - Demonstrations (EPO-Demos) are recorded video education demonstrations performed on the International Space Station (ISS) by crewmembers using hardware already onboard the ISS. EPO-Demos are videotaped, edited, and used to enhance existing NASA education resources and programs for educators and students in grades K-12. EPO-Demos are designed to support the NASA mission to inspire the next generation of explorers.

  19. Edible Astronomy Demonstrations

    NASA Astrophysics Data System (ADS)

    Lubowich, Donald A.

    2007-12-01

    Astronomy demonstrations with edible ingredients are an effective way to increase student interest and knowledge of astronomical concepts. This approach has been successful with all age groups from elementary school through college students - and the students remember these demonstrations after they are presented. In this poster I describe edible demonstrations I have created to simulate the expansion of the universe (using big-bang chocolate chip cookies); differentiation during the formation of the Earth and planets (using chocolate or chocolate milk with marshmallows, cereal, candy pieces or nuts); and radioactivity/radioactive dating (using popcorn). Other possible demonstrations include: plate tectonics (crackers with peanut butter and jelly); convection (miso soup or hot chocolate); mud flows on Mars (melted chocolate poured over angel food cake); formation of the Galactic disk (pizza); formation of spiral arms (coffee with cream); the curvature of Space (Pringles); constellations patterns with chocolate chips and chocolate chip cookies; planet shaped cookies; star shaped cookies with different colored frostings; coffee or chocolate milk measurement of solar radiation; Oreo cookie lunar phases. Sometimes the students eat the results of the astronomical demonstrations. These demonstrations are an effective teaching tool and can be adapted for cultural, culinary, and ethnic differences among the students.

  20. Defect Depth Measurement Using White Light Interferometry

    NASA Technical Reports Server (NTRS)

    Parker, Don; Starr, Stan

    2009-01-01

    The objectives of the White Light Interferometry project are the following: (1) Demonstrate a small hand-held instrument capable of performing inspections of identified defects on Orbiter outer pane window surfaces. (2) Build and field-test a prototype device using miniaturized optical components. (3) Modify the instrument based on field testing and begin the conversion of the unit to become a certified shop-aid.

  1. Defect Inspection of Flip Chip Solder Bumps Using an Ultrasonic Transducer

    PubMed Central

    Su, Lei; Shi, Tielin; Xu, Zhensong; Lu, Xiangning; Liao, Guanglan

    2013-01-01

    Surface mount technology has spurred a rapid decrease in the size of electronic packages, where solder bump inspection of surface mount packages is crucial in the electronics manufacturing industry. In this study we demonstrate the feasibility of using a 230 MHz ultrasonic transducer for nondestructive flip chip testing. The reflected time domain signal was captured when the transducer scanning the flip chip, and the image of the flip chip was generated by scanning acoustic microscopy. Normalized cross-correlation was used to locate the center of solder bumps for segmenting the flip chip image. Then five features were extracted from the signals and images. The support vector machine was adopted to process the five features for classification and recognition. The results show the feasibility of this approach with high recognition rate, proving that defect inspection of flip chip solder bumps using the ultrasonic transducer has high potential in microelectronics packaging.

  2. Laminar flow control SPF/08 feasibility demonstration

    NASA Technical Reports Server (NTRS)

    Ecklund, R. C.; Williams, N. R.

    1981-01-01

    The feasibility of applying superplastic forming/diffusion bonding (SPF/DB) technology to laminar flow control (LFC) system concepts was demonstrated. Procedures were developed to produce smooth, flat titanium panels, using thin -0.016 inch sheets, meeting LFC surface smoothness requirements. Two large panels 28 x 28 inches were fabricated as final demonstration articles. The first was flat on the top and bottom sides demonstrating the capability of the tooling and the forming and diffusion bonding procedures to produce flat, defect free surfaces. The second panel was configurated for LFC porous panel treatment by forming channels with dimpled projections on the top side. The projections were machined away leaving holes extending into the panel. A perforated titanium sheet was adhesively bonded over this surface to complete the LFC demonstration panel. The final surface was considered flat enough to meet LFC requirements for a jet transport aircraft in cruising flight.

  3. The effect of defect cluster size and interpolation on radiographic image quality

    NASA Astrophysics Data System (ADS)

    Töpfer, Karin; Yip, Kwok L.

    2011-03-01

    For digital X-ray detectors, the need to control factory yield and cost invariably leads to the presence of some defective pixels. Recently, a standard procedure was developed to identify such pixels for industrial applications. However, no quality standards exist in medical or industrial imaging regarding the maximum allowable number and size of detector defects. While the answer may be application specific, the minimum requirement for any defect specification is that the diagnostic quality of the images be maintained. A more stringent criterion is to keep any changes in the images due to defects below the visual threshold. Two highly sensitive image simulation and evaluation methods were employed to specify the fraction of allowable defects as a function of defect cluster size in general radiography. First, the most critical situation of the defect being located in the center of the disease feature was explored using image simulation tools and a previously verified human observer model, incorporating a channelized Hotelling observer. Detectability index d' was obtained as a function of defect cluster size for three different disease features on clinical lung and extremity backgrounds. Second, four concentrations of defects of four different sizes were added to clinical images with subtle disease features and then interpolated. Twenty observers evaluated the images against the original on a single display using a 2-AFC method, which was highly sensitive to small changes in image detail. Based on a 50% just-noticeable difference, the fraction of allowed defects was specified vs. cluster size.

  4. Live demonstration of microcirculation in the deep fascia and its implication.

    PubMed

    Bhattacharya, V; Watts, Rajesh Kumar; Reddy, G R

    2005-02-01

    The rich vascular network in the deep fascia has been emphasized by various scientists, but the actual demonstration of live circulation in the deep fascia has not previously been witnessed. Encouraged by the sight of live circulation in the web membrane of toad hind limb, a successful attempt was made to demonstrate the live circulation in the vascular network of the deep fascia. Fascial extensions of inferiorly based fasciocutaneous flaps were dissected in five patients with distal leg and heel defects. The fascial extension in continuity with a proximal retrograde fasciocutaneous flap was mounted on a glass slide and examined under a microscope. The authors witnessed the live microcirculation and the movement of individual red blood corpuscles in vascular channels of the deep fascia. The authors also noticed that the deep fascia has two layers with circulations that are independent of one other. A video recording was made to document these important features.

  5. Solar Energy Demonstrations

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Solar energy furnishes all of the heating and hot water needs, plus 80 percent of the air conditioning, for the two-story Reedy Creek building. A unique feature of this installation is that the 16 semi-cylindrical solar collectors (center photo on opposite page with closeup of a single collector below it) are not mounted atop the roof as is customary, they actually are the roof. This arrangement eliminates the usual trusses, corrugated decking and insulating concrete in roof construction; that, in turn, reduces overall building costs and makes the solar installation more attractive economically. The Reedy Creek collectors were designed and manufactured by AAI Corporation of Baltimore, Maryland.

  6. Autonomous docking ground demonstration

    NASA Technical Reports Server (NTRS)

    Lamkin, Steve L.; Le, Thomas Quan; Othon, L. T.; Prather, Joseph L.; Eick, Richard E.; Baxter, Jim M.; Boyd, M. G.; Clark, Fred D.; Spehar, Peter T.; Teters, Rebecca T.

    1991-01-01

    The Autonomous Docking Ground Demonstration is an evaluation of the laser sensor system to support the docking phase (12 ft to contact) when operated in conjunction with the guidance, navigation, and control (GN&C) software. The docking mechanism being used was developed for the Apollo/Soyuz Test Program. This demonstration will be conducted using the 6-DOF Dynamic Test System (DTS). The DTS simulates the Space Station Freedom as the stationary or target vehicle and the Orbiter as the active or chase vehicle. For this demonstration, the laser sensor will be mounted on the target vehicle and the retroflectors will be on the chase vehicle. This arrangement was chosen to prevent potential damage to the laser. The laser sensor system, GN&C, and 6-DOF DTS will be operated closed-loop. Initial conditions to simulate vehicle misalignments, translational and rotational, will be introduced within the constraints of the systems involved.

  7. TRUEX hot demonstration

    SciTech Connect

    Chamberlain, D.B.; Leonard, R.A.; Hoh, J.C.; Gay, E.C.; Kalina, D.G.; Vandegrift, G.F.

    1990-04-01

    In FY 1987, a program was initiated to demonstrate technology for recovering transuranic (TRU) elements from defense wastes. This hot demonstration was to be carried out with solution from the dissolution of irradiated fuels. This recovery would be accomplished with both PUREX and TRUEX solvent extraction processes. Work planned for this program included preparation of a shielded-cell facility for the receipt and storage of spent fuel from commercial power reactors, dissolution of this fuel, operation of a PUREX process to produce specific feeds for the TRUEX process, operation of a TRUEX process to remove residual actinide elements from PUREX process raffinates, and processing and disposal of waste and product streams. This report documents the work completed in planning and starting up this program. It is meant to serve as a guide for anyone planning similar demonstrations of TRUEX or other solvent extraction processing in a shielded-cell facility.

  8. Nonlinear optical imaging of defects in cubic silicon carbide epilayers.

    PubMed

    Hristu, Radu; Stanciu, Stefan G; Tranca, Denis E; Matei, Alecs; Stanciu, George A

    2014-06-11

    Silicon carbide is one of the most promising materials for power electronic devices capable of operating at extreme conditions. The widespread application of silicon carbide power devices is however limited by the presence of structural defects in silicon carbide epilayers. Our experiment demonstrates that optical second harmonic generation imaging represents a viable solution for characterizing structural defects such as stacking faults, dislocations and double positioning boundaries in cubic silicon carbide layers. X-ray diffraction and optical second harmonic rotational anisotropy were used to confirm the growth of the cubic polytype, atomic force microscopy was used to support the identification of silicon carbide defects based on their distinct shape, while second harmonic generation microscopy revealed the detailed structure of the defects. Our results show that this fast and noninvasive investigation method can identify defects which appear during the crystal growth and can be used to certify areas within the silicon carbide epilayer that have optimal quality.

  9. Innovative technology demonstrations

    SciTech Connect

    Anderson, D.B.; Luttrell, S.P.; Hartley, J.N.; Hinchee, R.

    1992-08-01

    Environmental Management Operations (EMO) is conducting an Innovative Technology Demonstration Program for Tinker Air Force Base (TAFB). Several innovative technologies are being demonstrated to address specific problems associated with remediating two contaminated test sites at the base. Cone penetrometer testing (CPT) is a form of testing that can rapidly characterize a site. This technology was selected to evaluate its applicability in the tight clay soils and consolidated sandstone sediments found at TAFB. Directionally drilled horizontal wells was selected as a method that may be effective in accessing contamination beneath Building 3001 without disrupting the mission of the building, and in enhancing the extraction of contamination both in ground water and in soil. A soil gas extraction (SGE) demonstration, also known as soil vapor extraction, will evaluate the effectiveness of SGE in remediating fuels and TCE contamination contained in the tight clay soil formations surrounding the abandoned underground fuel storage vault located at the SW Tanks Site. In situ sensors have recently received much acclaim as a technology that can be effective in remediating hazardous waste sites. Sensors can be useful for determining real-time, in situ contaminant concentrations during the remediation process for performance monitoring and in providing feedback for controlling the remediation process. Following the SGE demonstration, the SGE system and SW Tanks test site will be modified to demonstrate bioremediation as an effective means of degrading the remaining contaminants in situ. The bioremediation demonstration will evaluate a bioventing process in which the naturally occurring consortium of soil bacteria will be stimulated to aerobically degrade soil contaminants, including fuel and TCE, in situ.

  10. Demonstrating marketing accountability.

    PubMed

    Gombeski, William R; Britt, Jason; Taylor, Jan; Riggs, Karen; Wray, Tanya; Adkins, Wanda; Springate, Suzanne

    2008-01-01

    Pressure on health care marketers to demonstrate effectiveness of their strategies and show their contribution to organizational goals is growing. A seven-tiered model based on the concepts of structure (having the right people, systems), process (doing the right things in the right way), and outcomes (results) is discussed. Examples of measures for each tier are provided and the benefits of using the model as a tool for measuring, organizing, tracking, and communicating appropriate information are provided. The model also provides a framework for helping management understand marketing's value and can serve as a vehicle for demonstrating marketing accountability.

  11. Gigashot Optical Laser Demonstrator

    SciTech Connect

    Deri, R. J.

    2015-10-13

    The Gigashot Optical Laser Demonstrator (GOLD) project has demonstrated a novel optical amplifier for high energy pulsed lasers operating at high repetition rates. The amplifier stores enough pump energy to support >10 J of laser output, and employs conduction cooling for thermal management to avoid the need for expensive and bulky high-pressure helium subsystems. A prototype amplifier was fabricated, pumped with diode light at 885 nm, and characterized. Experimental results show that the amplifier provides sufficient small-signal gain and sufficiently low wavefront and birefringence impairments to prove useful in laser systems, at repetition rates up to 60 Hz.

  12. Demonstrating Supernova Remnant Evolution

    NASA Astrophysics Data System (ADS)

    Leahy, Denis A.; Williams, Jacqueline

    2017-01-01

    We have created a software tool to calculate at display supernova remnant evolution which includes all stages from early ejecta dominated phase to late-time merging with the interstellar medium. The software was created using Python, and can be distributed as Python code, or as an executable file. The purpose of the software is to demonstrate the different phases and transitions that a supernova remnant undergoes, and will be used in upper level undergraduate astrophysics courses as a teaching tool. The usage of the software and its graphical user interface will be demonstrated.

  13. Defective pyrite (100) surface: An ab initio study

    SciTech Connect

    Stirling, Andras; Bernasconi, Marco; Parrinello, Michele

    2007-04-15

    The structural and electronic properties of sulfur monomeric defects at the FeS{sub 2}(100) surface have been studied by periodic density-functional calculations. We have shown that for a monomeric sulfur bound to an originally fivefold coordinated surface Fe site, the defect core features a triplet electronic ground state with unpaired spins localized on the exposed Fe-S unit. At this site, the iron and sulfur ions have oxidation states +4 and -2, respectively. This defect can be seen as produced via heterolytic bond breaking of the S-S sulfur dimer followed by a Fe-S redox reaction. The calculated sulfur 2p core-level shifts of the monomeric defects are in good agreement with experimental photoemission spectra, which allow a compelling assignment of the different spectroscopic features. The effect of water on the stability of the defective surface has also been studied, and it has been shown that the triplet state is stable against the wetting of the surface. The most important implications of the presence of the monomeric sulfur defect on the reactivity are also discussed.

  14. Calculus Demonstrations Using MATLAB

    ERIC Educational Resources Information Center

    Dunn, Peter K.; Harman, Chris

    2002-01-01

    The note discusses ways in which technology can be used in the calculus learning process. In particular, five MATLAB programs are detailed for use by instructors or students that demonstrate important concepts in introductory calculus: Newton's method, differentiation and integration. Two of the programs are animated. The programs and the…

  15. A Biofeedback Demonstration.

    ERIC Educational Resources Information Center

    Garrity, Michael K.

    1978-01-01

    Describes a demonstration for measurement of biophysical signals produced by the human body. The signals, after amplification, could provide acoustical feedback through a voltage-controlled oscillator (VCO), or they could be seen either with an oscilloscope or a high speed chart recorder. (GA)

  16. Polarized Light: Three Demonstrations.

    ERIC Educational Resources Information Center

    Goehmann, Ruth; Welty, Scott

    1984-01-01

    Describes three demonstrations used in the Chicago Museum of Science and Industry polarized light show. The procedures employed are suitable for the classroom by using smaller polarizers and an overhead projector. Topic areas include properties of cellophane tape, nondisappearing arrows, and rope through a picket fence. (JN)

  17. Demonstrating the Gas Laws.

    ERIC Educational Resources Information Center

    Holko, David A.

    1982-01-01

    Presents a complete computer program demonstrating the relationship between volume/pressure for Boyle's Law, volume/temperature for Charles' Law, and volume/moles of gas for Avagadro's Law. The programing reinforces students' application of gas laws and equates a simulated moving piston to theoretical values derived using the ideal gas law.…

  18. A Fruity Biochemistry Demonstration

    ERIC Educational Resources Information Center

    Shmaefsky, Brian R.

    2005-01-01

    Classroom demonstrations are a great vehicle for getting students to apply information they have heard in a lecture. Educational research is replete with data showing that concept application in an inquiry setting reinforces long-term science content retention. This means that students learn best when they experience applications of concepts and…

  19. DEMONSTRATION PLAN FIELD MEASUREMENT ...

    EPA Pesticide Factsheets

    The demonstration of innovative field measurement devices for total petroleum hydrocarbons (TPH) in soil is being conducted under the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation Program in June 2000 at the Navy Base Ventura County site in Port Hueneme, California. The primary purpose of the demonstration is to evaluate innovative field measurement devices for TPH in soil based on their performance and cost as compared to a conventional, off-site laboratory analytical method. The seven field measurement devices listed below will be demonstrated. CHEMetrics, Inc.'s, RemediAidTm Total Petroleum Hydrocarbon Starter Kit Wilks Enterprise, Inc.'s, Infracal' TOG/TPH Analyzer, Models CVH and HATR-T Horiba Instruments, Incorporated's, OCMA-350 Oil Content Analyzer Dexsil' Corporation's PetroFLAGTm Hydrocarbon Test Kit for Soil Environmental Systems Corporation's Synchronous Scanning Luminoscope siteLAB@ Corporation's Analytical Test Kit UVF-3 I OOA Strategic Diagnostics, Inc.'s, EnSys Petro Test System This demonstration plan describes the procedures that will be used to verify the performance and cost of each field measurement device. The plan incorporates the quality assurance and quality control elements needed to generate data of sufficient quality to document each device's performance and cost. A separate innovative technology verification report (ITVR) will be prepared for each device. The ITVRs will present the demonstratio

  20. ROUGH ROCK DEMONSTRATION SCHOOL.

    ERIC Educational Resources Information Center

    FORBES, JACK

    THE ROUGH ROCK DEMONSTRATION SCHOOL IS LOCATED IN NORTHEASTERN ARIZONA, WHERE THE NAVAJO LANGUAGE IS UNIVERSALLY SPOKEN BY THE NAVAJO PEOPLE. IT IS LOCATED ON A NAVAJO RESERVATION AND WAS DESIGNED AS A BIA EXPERIMENTAL SCHOOL TO SERVE 200 ELEMENTARY PUPILS, MOST OF WHOM ARE IN THE BOARDING SCHOOL SITUATION. AN OBJECTIVE OF THE SCHOOL IS TO GAIN…

  1. Participatory Lecture Demonstrations.

    ERIC Educational Resources Information Center

    Battino, Rubin

    1979-01-01

    The use of participatory lecture demonstrations in the classroom is described. Examples are given for the following topics: chromatography, chemical kinetics, balancing equations, the gas laws, kinetic molecular theory, Henry's law of gas solubility, electronic energy levels in atoms, and translational, vibrational, and rotational energies of…

  2. Demonstrating carbon capture

    SciTech Connect

    Qader, A.; Hooper, B.; Stevens, G.

    2009-11-15

    Australia is at the forefront of advancing CCS technology. The CO2CRC's H3 (Post-combustion) and Mulgrave (pre-combustion) capture projects are outlined. The capture technologies for these 2 demonstration projects are described. 1 map., 2 photos.

  3. Astronomy Demonstrations and Models.

    ERIC Educational Resources Information Center

    Eckroth, Charles A.

    Demonstrations in astronomy classes seem to be more necessary than in physics classes for three reasons. First, many of the events are very large scale and impossibly remote from human senses. Secondly, while physics courses use discussions of one- and two-dimensional motion, three-dimensional motion is the normal situation in astronomy; thus,…

  4. Overhead Projector Demonstrations.

    ERIC Educational Resources Information Center

    Kolb, Doris, Ed.

    1988-01-01

    Provides two demonstrations: (1) electrolyte migration of ions using colored ions which cross a strip of gelatin allowing for noticeable migration; and (2) photochemical reduction of Fe+3 by the citrate ion. Points out both reactions can be done in a Petri dish using common lab materials. (MVL)

  5. A Magnetic Circuit Demonstration.

    ERIC Educational Resources Information Center

    Vanderkooy, John; Lowe, June

    1995-01-01

    Presents a demonstration designed to illustrate Faraday's, Ampere's, and Lenz's laws and to reinforce the concepts through the analysis of a two-loop magnetic circuit. Can be made dramatic and challenging for sophisticated students but is suitable for an introductory course in electricity and magnetism. (JRH)

  6. Overhead Projector Demonstrations.

    ERIC Educational Resources Information Center

    Kolb, Doris, Ed.

    1989-01-01

    Described are three chemistry demonstrations: (1) a simple qualitative technique for taste pattern recognition in structure-activity relationships; (2) a microscale study of gaseous diffusion using bleach, HCl, ammonia, and phenolphthalein; and (3) the rotation of polarized light by stereoisomers of limonene. (MVL)

  7. Organic Lecture Demonstrations.

    ERIC Educational Resources Information Center

    Silversmith, Ernest F.

    1988-01-01

    Provides a listing of 35 demonstrations designed to generate interest in organic chemistry and help put points across. Topics include opening lecture; molecular structure and properties; halogenation; nucleophilic substitution, alkenes and dienes, stereochemistry, spectroscopy, alcohols and phenols, aldehydes and ketones; carboxylic acids, amines,…

  8. Repository Drift Backfilling Demonstrator

    SciTech Connect

    Londe, I.; Dubois, J.Ph.; Bauer, C.

    2008-07-01

    The 'Backfilling Demonstrator' is one of the technological demonstrators developed by ANDRA in the framework of the feasibility studies for a geological repository for high-level long-lived (HL-LL waste) within a clay formation. The demonstrator concerns the standard and supporting backfills as defined in Andra's 2005 design. The standard backfill is intended to fill up almost all drifts of the underground repository in order to limit any deformation of the rock after the degradation of the drift lining. The supporting backfill only concerns a small portion of the volume to be backfilled in order to counter the swelling pressure of the swelling clay contained in the sealing structures. The first objective of the demonstrator was to show the possibility of manufacturing a satisfactory backfill, in spite of the exiguity of the underground structures, and of reusing as much as possible the argillite muck. For the purpose of this experiment, the argillite muck was collected on Andra's work-site for the implementation of an underground research laboratory. Still ongoing, the second objective is to follow up the long-term evolution of the backfill. Approximately 200 m{sup 3} of compacted backfill material have been gathered in a large concrete tube simulating a repository drift. The standard backfill was manufactured exclusively with argillite. The supporting backfill was made by forming a mixture of argillite and sand. Operations were carried out mostly at Richwiller, close to Mulhouse, France. The objectives of the demonstrator were met: an application method was tested and proven satisfactory. The resulting dry densities are relatively high, although the moduli of deformation do not always reach the set goal. The selected objective for the demonstrator was a dry density corresponding to a relatively high compaction level (95% of the standard Proctor optimum [SPO]), for both pure argillite and the argillite-sand mixture. The plate-percussion compaction technique was

  9. Topological defects in extended inflation

    NASA Technical Reports Server (NTRS)

    Copeland, Edmund J.; Kolb, Edward W.; Liddle, Andrew R.

    1990-01-01

    The production of topological defects, especially cosmic strings, in extended inflation models was considered. In extended inflation, the Universe passes through a first-order phase transition via bubble percolation, which naturally allows defects to form at the end of inflation. The correlation length, which determines the number density of the defects, is related to the mean size of bubbles when they collide. This mechanism allows a natural combination of inflation and large scale structure via cosmic strings.

  10. The RF performance of cavity made from defective niobium material determined by Eddy Current Scanning

    SciTech Connect

    Wu, G.; Cooley, L.; Sergatskov, D.; Ozelis, J.; Brinkmann, A.; Singer, W.; Singer, X.; Pekeler, M.

    2010-10-01

    Eddy current scanning (ECS) has been used to screen niobium sheets to avoid defective material being used in costly cavity fabrication. The evaluation criterion of this quality control tool is not well understood. Past surface studies showed some features were shallow enough to be removed by chemical etching. The remaining features were identified to be small number of deeper inclusions, but mostly unidentifiable features (by chemical analysis). A real cavity made of defective niobium material has been tested. The cavity achieved high performance with comparable results to the cavities made from defect free cavities. Temperature mapping could help to define the control standard clearly.

  11. Phenolphthalein—Pink Tornado Demonstration

    NASA Astrophysics Data System (ADS)

    Prall, Bruce R.

    2008-04-01

    The phenolphthalein-pink tornado demonstration utilizes the vortex generated by a spinning magnetic stirring bar in a 1 L graduated cylinder containing 0.01 M HCl to demonstrate Le Châtelier's principle as it applies to the phenolphthalein equilibrium in water H 2 In + 2H 2 O 2H 2 O + + In 2 - where H 2 In is phenophthalein. The addition of 3-4 drops of phenolphthalein indicator solution followed immediately by 3-4 drops of 50% (w/w) NaOH to the vortex of the HCl solution results in a shift to the right in the equilibrium owing to the reaction of OH - + H 3 O + to form water. This shift is accompanied by the vortex becoming visible by the appearance of a pinkish-red color caused by an increase in In 2- concentration within the localized region of the vortex. The demonstration also provides one an excellent opportunity to discuss the topics of limiting reagent and reagent in excess. Some insight regarding the extent to which uniform mixing is achieved when using a magnetic stirrer is also provided. Included is a note from the Feature Editor, Ed Vitz.

  12. Atomic Bond Deficiency Defects in Amorphous Metals

    NASA Astrophysics Data System (ADS)

    Zhu, Aiwu; Shiflet, Gary J.; Poon, S. Joseph

    2012-10-01

    Atomic bond deficiency (BD) is considered to be characteristic structural defects in amorphous metals. They are the necessary feature of local atomic configurations that facilitate various atomic transports under different driving forces. Compared with vacancies in crystalline solids, they are "small" in terms of their formation energies, volume costs, and elementary steps involved in atomic transport. This article reviews the authors' recent efforts made to analyze how various local configurations containing BD are related to amorphous metal's unique characteristics, such as glass transition, diffusion, shear flow, and structural relaxation.

  13. The study of develop optimization to control various resist defect in Photomask fabrication

    NASA Astrophysics Data System (ADS)

    Lim, JongHoon; Kim, ByungJu; Son, JaeSik; Park, EuiSang; Kim, SangPyo; Yim, DongGyu

    2015-07-01

    To reduce the pattern size in photomask is an inevitable trend because of the minimization of chip size. So it makes a big challenge to control defects in photomask industry. Defects below a certain size that had not been any problem in previous technology node are becoming an issue as the patterns are smaller. Therefore, the acceptable tolerance levels for current defect size and quantity are dramatically reduced. Because these defects on photomask can be the sources of the repeating defects on wafer, small size defects smaller than 200nm should not be ignored any more. Generally, almost defects are generated during develop process and etch process. Especially it is difficult to find the root cause of defects formed during the develop process because of their various types and very small size. In this paper, we studied how these small defects can be eliminated by analyzing the defects and tuning the develop process. There are 3 types of resist defects which are named as follows. The first type is `Popcorn' defect which is mainly occurred in negative resist and exists on the dark features. The second type is `Frog eggs' defect which is occurred in 2nd process of HTPSM and exists on the wide space area. The last type is `Spot' defect which also exists on the wide space area. These defects are generally appeared on the entire area of a plate and the number of these defects is about several hundred. It is thought that the original source is the surface's hydrophilic state before develop process or the incongruity between resist and developer. This study shows that the optimizing the develop process can be a good solution for some resist defects.

  14. Detection of electrical defects with SEMVision in semiconductor production mode manufacturing

    NASA Astrophysics Data System (ADS)

    Newell, Travis; Tillotson, Brock; Pearl, Haim; Miller, Andrei

    2016-03-01

    In the semiconductor manufacturing process, defects often occur due to a marginal process window that affects the lithography and etch processes. These defects can result in bridging patterns and overlay issues, which consequently cause electrical shorts and partially etched vias producing electrical opens. SEM tools are used to find electrical failures through voltage contrast techniques. Manufacturers who fabricate with older process technology nodes often need to use their tool set more efficiently. This paper demonstrates an application of conventional SEM review with image to golden reference image inspection capabilities in Automatic Process Inspection (API ) mode to perform electrical inspections of die features. This paper details how to use a SEM review tool to detect systematic electrical defects. This methodology can prove beneficial while monitoring and developing patterning techniques for a specific design rule by catching electrical shorts and opens that are more visible at a lower resolution inspection used in process monitoring. Outcomes of this effort show that conventional review SEM techniques, using known areas prone to process inconsistencies derived from features pushing the design rule, have the capability to effectively and efficiently monitor fabrication process while implemented in a production setting at process nodes between 100 to 200 nm. Using e-beam review tools offers several advantages and disadvantages. This paper demonstrates that by using a SEM review tool and selecting die locations for imaging that are more likely to fail electrically, manufacturers can use SEM automatic review capabilities more effectively and efficiently. The application developed may also be applied in fabrication facilities that have limited yield monitoring capacity. This paper is a result of collaboration between Applied Materials and Microchip Technology Inc.

  15. Who named the quantum defect?

    SciTech Connect

    Rau, A.R.P.; Inokuti, M.

    1997-08-01

    The notion of the quantum defect is important in atomic and molecular spectroscopy and also in unifying spectroscopy with collision theory. In the latter context, the quantum defect may be viewed as an ancestor of the phase shift. However, the origin of the term quantum defect does not seem to be explained in standard textbooks. It occurred in a 1921 paper by Schroedinger, preceding quantum mechanics, yet giving the correct meaning as an index of the short-range interactions with the core of an atom. The authors present the early history of the quantum-defect idea, and sketch its recent developments.

  16. Defect-Stabilized Phases in Extensile Active Nematics

    NASA Astrophysics Data System (ADS)

    Redner, Gabriel; Decamp, Stephen; Dogic, Zvonimir; Hagan, Michael

    2015-03-01

    Active nematics are liquid crystals which are driven out of equilibrium by energy-dissipating active stresses. The equilibrium nematic state is unstable in these materials, leading to beautiful and surprising behaviors including the spontaneous generation of topological defect pairs which stream through the system and later annihilate, yielding a complex, seemingly chaotic dynamical steady-state. In this talk, I will describe the emergence of order from this chaos in the form of previously unknown broken-symmetry phases in which the topological defects themselves undergo orientational ordering. We have identified these defect-ordered phases in two realizations of an active nematic: first, a suspension of extensile bundles of microtubules and molecular motor proteins, and second, a computational model of extending hard rods. I will describe the defect-stabilized phases that manifest in these systems, our current understanding of their origins, and discuss whether such phases may be a general feature of extensile active nematics.

  17. An Automated Classification Technique for Detecting Defects in Battery Cells

    NASA Technical Reports Server (NTRS)

    McDowell, Mark; Gray, Elizabeth

    2006-01-01

    Battery cell defect classification is primarily done manually by a human conducting a visual inspection to determine if the battery cell is acceptable for a particular use or device. Human visual inspection is a time consuming task when compared to an inspection process conducted by a machine vision system. Human inspection is also subject to human error and fatigue over time. We present a machine vision technique that can be used to automatically identify defective sections of battery cells via a morphological feature-based classifier using an adaptive two-dimensional fast Fourier transformation technique. The initial area of interest is automatically classified as either an anode or cathode cell view as well as classified as an acceptable or a defective battery cell. Each battery cell is labeled and cataloged for comparison and analysis. The result is the implementation of an automated machine vision technique that provides a highly repeatable and reproducible method of identifying and quantifying defects in battery cells.

  18. Impact of curvature on topological defects

    NASA Astrophysics Data System (ADS)

    Mesarec, L.; Góźdź, W.; Iglič, A.; Kralj, S.

    2017-01-01

    We analyze the impact of extrinsic and intrinsic curvature on positions of topological defects (TDs) in two-dimensional (2D) nematic films. We demonstrate that both these curvature contributions are commonly present and are expected to be weighted by comparable elastic constants. A simple Landau-de Gennes approach in terms of tensor nematic order parameter is used to numerically demonstrate impact of the curvatures on position of TDs on 2D ellipsoidal nematic shells. In particular, in oblate ellipsoids the extrinsic and intrinsic elastic terms enforce conflicting tendencies to positions of TDs.

  19. Nucla CFB Demonstration Project

    SciTech Connect

    Not Available

    1990-12-01

    This report documents Colorado-Ute Electric Association's Nucla Circulating Atmospheric Fluidized-Bed Combustion (AFBC) demonstration project. It describes the plant equipment and system design for the first US utility-size circulating AFBC boiler and its support systems. Included are equipment and system descriptions, design/background information and appendices with an equipment list and selected information plus process flow and instrumentation drawings. The purpose of this report is to share the information gathered during the Nucla circulating AFBC demonstration project and present it so that the general public can evaluate the technical feasibility and cost effectiveness of replacing pulverized or stoker-fired boiler units with circulating fluidized-bed boiler units. (VC)

  20. LIMB Demonstration Project Extension

    SciTech Connect

    Not Available

    1988-03-15

    The basic goal of the Limestone Injection Multistage Burner (LIMB) demonstration is to extend LIMB technology development to a full-scale application on a representative wall-fired utility boiler. The successful retrofit of LIMB to an existing boiler is expected to demonstrate that (a) reductions of 50 percent or greater in SO{sub x} and NO{sub x} emissions can be achieved at a fraction of the cost of add-on FGD systems, (b) boiler reliability, operability, and steam production can be maintained at levels existing prior to LIMB retrofit, and (c) technical difficulties attributable to LIMB operation, such as additional slagging and fouling, changes in ash disposal requirements, and an increased particulate load, can be resolved in a cost-effective manner. The primary fuel to be used will be an Ohio bituminous coal having a nominal sulfur content of 3 percent or greater.

  1. Education Demonstration Equipment

    NASA Astrophysics Data System (ADS)

    Nagy, A.; Lee, R. L.

    2005-10-01

    Several GA Fusion Education Program plasma related demonstration items were developed this year. A 120 V ac powered electromagnetic coil shows eddy current levitation over an aluminum sheet and continuously changing magnetic force interactions using additional permanent magnets. A 300 V dc plasma device, with variable current capability and analog data ports, is used to develop plasma I/V plots. An on-demand (via push button) fully enclosed 24 in. Jacob's ladder provides air plasma and buoyancy effects. A low cost Mason jar vacuum chamber filled with inert gas shows pressure and gas species plasma characteristics when excited by a Tesla coil. These demonstration items are used in the Scientist-In-the-Classroom program, GA facility tours, and teacher seminars to present plasma to students and teachers. Three very popular Build-It workshops were held to enable teachers to build these items and take them back to their classroom.

  2. LIMB Demonstration Project Extension

    SciTech Connect

    Not Available

    1988-09-15

    The basic goal of the Limestone Injection Multistage Burner (LIMB) demonstration is to extend LIMB technology development to a full-scale application on a representative wall-fired utility boiler. The successful retrofit of LIMB to an existing boiler is expected to demonstrate that (a) reductions of 50 percent or greater in SO and NO emissions can be achieved at a fraction of the cost of add-on FGD systems, (b) boiler reliability, operability, and steam production can be maintained at levels existing prior to LIMB retrofit, and (c) technical difficulties attributable to LIMB operation, such as additional slagging and fouling, changes in ash disposal requirements, and an increased particulate load, can be resolved in a cost-effective manner. The primary fuel to be used will be an Ohio bituminous coal having a nominal sulfur content of 3 percent or greater.

  3. Chemical Domino Demonstration

    NASA Astrophysics Data System (ADS)

    Alexander, M. Dale

    1998-04-01

    The Chemical Domino Demonstration is both educational and entertaining. It provides an excellent means for a review of chemical concepts at the conclusion of a general chemistry course. This demonstration consists of a number of different chemical reactions occurring in sequence in a Rube Goldberg-type apparatus. These reactions include the reduction of water by an active metal, the oxidation of a moderately active metal by an acid, reduction of metallic ions by a metal of greater activity, acid-base neutralization reactions in solution monitored with indicators, a gas-phase acid-base neutralization reaction, decomposition of a compound, precipitation of an insoluble salt, substitution reactions of coordination complexes, and pyrotechnic oxidation-reduction reactions including a hypergolic oxidation-reduction reaction, an intramolecular oxidation-reduction reaction, and the combustion of a flammable gas.

  4. Mars Umbilical Technology Demonstrator

    NASA Technical Reports Server (NTRS)

    Houshangi, Nasser

    2000-01-01

    The objective of this project is to develop a autonomous umbilical mating for the mars umbilical technology demonstrator. The Mars Umbilical Technology Demonstrator (MUTD) shall provide electrical power and fiber optic data cable connections between two simulated mars vehicles. The Omnibot is used to provide the mobile base for the system. The mate to umbilical plate is mounted on a three axis Cartesian table, which is installed on the Omnibot mobile base. The Omnibot is controlled in a teleoperated mode. The operator using the vision system will guide the Omnibot to get close to the mate to plate. The information received from four ultrasonic sensors is used to identify the position of mate to plate and mate the umbilical plates autonomously. A successful experimentation verifies the approach.

  5. Arctic Craft Demonstration Report

    DTIC Science & Technology

    2012-11-01

    up the beach towards the NARL facility because beluga whales were in the area and they might be scared further offshore. He stated that the local...Eskimo Whaling Commission (AEWC) both to ensure the demonstration would not interfere with their sustenance hunting activities and also to inquire about...weather conditions were sunny with a light breeze. Occasional whale spouts were sighted in the distance but not close enough for mammal

  6. The Blowgun Demonstration Experiment

    ERIC Educational Resources Information Center

    Tsukamoto, Koji; Uchino, Masanori

    2008-01-01

    We have found that a simple demonstration experiment using a match or a cotton swab and a drinking straw or an acrylic pipe serves as an effective introduction to dynamics. The most basic apparatus has a cotton swab serving as a dart and the straw as the blowgun. When blown from a starting point near the exit end of the straw, the cotton swab does…

  7. Joined Beryllium Mirror Demonstrator

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip; Parsonage, Tom; Burdine, Robert (Technical Monitor)

    2001-01-01

    Fabrications of large Beryllium optical components are fundamentally limited by available facility capabilities. To overcome this limitation, NASA funded Brush Wellman Corp to study a Be joining process. Four 76 mm diameters samples and a 0.5 mm diameter Joined Beryllium Mirror Demonstrator (JBMD) were fabricated. This presentation will review the fabrication of these samples and summarize the results of their cryogenic testing at MSFCs XRCF.

  8. Great Lakes Demonstration 2

    DTIC Science & Technology

    2012-06-01

    Representatives from CG Districts 1, 5 , 13, and 17  Enbridge Pipeline, Co.  EPA  National Oceanic and Atmospheric Administration (NOAA)  Observers (CG...distances from the vessel‟s hull. (Figure 5 ) In that configuration, the recovery hose and hydraulic lines dragged across the surface of the nearby...No. CG-D-08-12 2. Government Accession Number 3. Recipient’s Catalog No. 4. Title and Subtitle Great Lakes Demonstration 2 Final Report 5

  9. Space Fabrication Demonstration System

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The completion of assembly of the beam builder and its first automatic production of truss is discussed. A four bay, hand assembled, roll formed members truss was built and tested to ultimate load. Detail design of the fabrication facility (beam builder) was completed and designs for subsystem debugging are discussed. Many one bay truss specimens were produced to demonstrate subsystem operation and to detect problem areas.

  10. Wannier Orbitals and Bonding Properties of Interstitial and Antisite Defects in GaN

    SciTech Connect

    Gao, Fei; Bylaska, Eric J.; El-Azab, Anter; Weber, William J.

    2004-12-06

    Intrinsic interstitial and antisite defects in GaN have been studied using density functional theory (DFT), and their configurations, electronic structures and bonding properties have been characterized using the Wannier function. All N interstitial configurations eventually transform into N-N split interstitials, between which two {pi} orbitals exist. The relaxation of a Ga antisite defect also leads to the formation of a N-N split configuration; however, its local Wannier orbitals are remarkably different from the N-N split interstitial. The different local Wannier orbitals around Ga interstitial configurations demonstrate that Ga interstitials are critical defects in GaN. The electronic orbitals of the Ga octahedral interstitial is, for example, greatly delocalized, and there are no covalent bonds formed between the interstitial and the surrounded atoms. The most striking feature is that Ga-Ga split interstitials can bridge the gap between non-bonded Ga atoms, thereby leading to a chain of four metallic-like-bonded Ga atoms in GaN, which may exhibit novel quantum properties.

  11. Simple SAR demonstrator

    NASA Astrophysics Data System (ADS)

    Kulpa, Krzysztof; Misiurewicz, Jacek; Baranowski, Piotr; Wojdołowicz, Grzegorz

    2008-01-01

    In this paper we present a simple SAR radar demonstrator build using commercially available (COTS) components. For the microwave analog front end, a standard police radar microwave head has been used. The Motorola DSP processor board, equipped with ADC and DAC, has been used for generating of modulating signal and for signal acquisition. The raw radar signal (I and Q components) have been recorded on 2.5" HDD. The signal processing has been performed on standard PC computer after copying the recorded data. The aim of constructing simple and relatively cheap demonstrator was to provide the students the real-life unclassified radar signals and motivate them to test and develop various kinds of SAR and ISAR algorithms, including image formation, motion compensation and autofocusing. The simple microwave frontend hardware has a lot of non-idealities, so for obtaining nice SAR image it was necessary to develop the number of correction algorithms at the calibration stage. The SAR demonstrator have been tested using car as a moving platform. The flight tests with a small airborne platform are planned for the summer.

  12. Lunar Water Resource Demonstration

    NASA Technical Reports Server (NTRS)

    Muscatello, Anthony C.

    2008-01-01

    In cooperation with the Canadian Space Agency, the Northern Centre for Advanced Technology, Inc., the Carnegie-Mellon University, JPL, and NEPTEC, NASA has undertaken the In-Situ Resource Utilization (ISRU) project called RESOLVE. This project is a ground demonstration of a system that would be sent to explore permanently shadowed polar lunar craters, drill into the regolith, determine what volatiles are present, and quantify them in addition to recovering oxygen by hydrogen reduction. The Lunar Prospector has determined these craters contain enhanced hydrogen concentrations averaging about 0.1%. If the hydrogen is in the form of water, the water concentration would be around 1%, which would translate into billions of tons of water on the Moon, a tremendous resource. The Lunar Water Resource Demonstration (LWRD) is a part of RESOLVE designed to capture lunar water and hydrogen and quantify them as a backup to gas chromatography analysis. This presentation will briefly review the design of LWRD and some of the results of testing the subsystem. RESOLVE is to be integrated with the Scarab rover from CMIJ and the whole system demonstrated on Mauna Kea on Hawaii in November 2008. The implications of lunar water for Mars exploration are two-fold: 1) RESOLVE and LWRD could be used in a similar fashion on Mars to locate and quantify water resources, and 2) electrolysis of lunar water could provide large amounts of liquid oxygen in LEO, leading to lower costs for travel to Mars, in addition to being very useful at lunar outposts.

  13. A single-molecule approach to ZnO defect studies: Single photons and single defects

    NASA Astrophysics Data System (ADS)

    Jungwirth, N. R.; Pai, Y. Y.; Chang, H. S.; MacQuarrie, E. R.; Nguyen, K. X.; Fuchs, G. D.

    2014-07-01

    Investigations that probe defects one at a time offer a unique opportunity to observe properties and dynamics that are washed out of ensemble measurements. Here, we present confocal fluorescence measurements of individual defects in ZnO nanoparticles and sputtered films that are excited with sub-bandgap energy light. Photon correlation measurements yield both antibunching and bunching, indicative of single-photon emission from isolated defects that possess a metastable shelving state. The single-photon emission is in the range of ˜560-720 nm and typically exhibits two broad spectral peaks separated by ˜150 meV. The excited state lifetimes range from 1 to 13 ns, consistent with the finite-size and surface effects of nanoparticles and small grains. We also observe discrete jumps in the fluorescence intensity between a bright state and a dark state. The dwell times in each state are exponentially distributed and the average dwell time in the bright (dark) state does (may) depend on the power of the exciting laser. Taken together, our measurements demonstrate the utility of a single-molecule approach to semiconductor defect studies and highlight ZnO as a potential host material for single-defect based applications.

  14. A single-molecule approach to ZnO defect studies: Single photons and single defects

    SciTech Connect

    Jungwirth, N. R.; Pai, Y. Y.; Chang, H. S.; MacQuarrie, E. R.; Nguyen, K. X.; Fuchs, G. D.

    2014-07-28

    Investigations that probe defects one at a time offer a unique opportunity to observe properties and dynamics that are washed out of ensemble measurements. Here, we present confocal fluorescence measurements of individual defects in ZnO nanoparticles and sputtered films that are excited with sub-bandgap energy light. Photon correlation measurements yield both antibunching and bunching, indicative of single-photon emission from isolated defects that possess a metastable shelving state. The single-photon emission is in the range of ∼560–720 nm and typically exhibits two broad spectral peaks separated by ∼150 meV. The excited state lifetimes range from 1 to 13 ns, consistent with the finite-size and surface effects of nanoparticles and small grains. We also observe discrete jumps in the fluorescence intensity between a bright state and a dark state. The dwell times in each state are exponentially distributed and the average dwell time in the bright (dark) state does (may) depend on the power of the exciting laser. Taken together, our measurements demonstrate the utility of a single-molecule approach to semiconductor defect studies and highlight ZnO as a potential host material for single-defect based applications.

  15. Defects in Silicene: Vacancy Clusters, Extended Line Defects, and Di-adatoms

    PubMed Central

    Li, Shuang; Wu, Yifeng; Tu, Yi; Wang, Yonghui; Jiang, Tong; Liu, Wei; Zhao, Yonghao

    2015-01-01

    Defects are almost inevitable during the fabrication process, and their existence strongly affects thermodynamic and (opto)electronic properties of two-dimensional materials. Very recent experiments have provided clear evidence for the presence of larger multi-vacancies in silicene, but their structure, stability, and formation mechanism remain largely unexplored. Here, we present a detailed theoretical study of silicene monolayer containing three types of defects: vacancy clusters, extended line defects (ELDs), and di-adatoms. First-principles calculations, along with ab initio molecular dynamics simulations, revealed the coalescence tendency of small defects and formation of highly stable vacancy clusters. The 5|8|5 ELD – the most favorable extended defect in both graphene and silicene sheets – is found to be easier to form in the latter case due to the mixed sp2/sp3 hybridization of silicon. In addition, hybrid functional calculations that contain part of the Hatree-Fock exchange energy demonstrated that the introduction of single and double silicon adatoms significantly enhances the stability of the system, and provides an effective approach on tuning the magnetic moment and band gap of silicene. PMID:25619941

  16. Nondestructive Superresolution Imaging of Defects and Nonuniformities in Metals, Semiconductors, Dielectrics, Composites, and Plants Using Evanescent Microwaves

    NASA Technical Reports Server (NTRS)

    Tabib-Azar, M.; Pathak, P. S.; Ponchak, G.; LeClair, S.

    1999-01-01

    We have imaged and mapped material nonuniformities and defects using microwaves generated at the end of a microstripline resonator with 0.4 micrometer lateral spatial resolution at 1 GHz. Here we experimentally examine the effect of microstripline substrate permittivity, the feedline-to-resonator coupling strength, and probe tip geometry on the spatial resolution of the probe. Carbon composites, dielectrics, semiconductors, metals, and botanical samples were scanned for defects, residual stresses, subsurface features, areas of different film thickness, and moisture content. The resulting evanescent microwave probe (EMP) images are discussed. The main objective of this work is to demonstrate the overall capabilities of the EMP imaging technique as well as to discuss various probe parameters that can be used to design EMPs for different applications.

  17. Defects involving interstitial boron in low-temperature irradiated silicon

    NASA Astrophysics Data System (ADS)

    Khirunenko, L. I.; Sosnin, M. G.; Duvanskii, A. V.; Abrosimov, N. V.; Riemann, H.

    2016-12-01

    Interstitial boron-related defects in silicon subjected to irradiation with 5 MeV electrons at a temperature of 80 K are investigated by Fourier-transform infrared absorption spectroscopy. This study demonstrates the radiation-enhanced annealing of interstitial boron during irradiation. We have revealed the interaction, which occurs in the course of irradiation, of diffusing interstitial boron atoms with one another and with interstitial oxygen. The local vibrational modes associated with these defects are identified, and the thermal stability of the defects is determined.

  18. Probing graphene defects and estimating graphene quality with optical microscopy

    SciTech Connect

    Lai, Shen; Kyu Jang, Sung; Jae Song, Young; Lee, Sungjoo

    2014-01-27

    We report a simple and accurate method for detecting graphene defects that utilizes the mild, dry annealing of graphene/Cu films in air. In contrast to previously reported techniques, our simple approach with optical microscopy can determine the density and degree of dislocation of defects in a graphene film without inducing water-related damage or functionalization. Scanning electron microscopy, confocal Raman and atomic force microscopy, and X-ray photoelectron spectroscopy analysis were performed to demonstrate that our nondestructive approach to characterizing graphene defects with optimized thermal annealing provides rapid and comprehensive determinations of graphene quality.

  19. Subsurface Defect Detection in FRP Composites Using Infrared Thermography

    NASA Astrophysics Data System (ADS)

    Halabe, U. B.; Vasudevan, A.; GangaRao, H. V. S.; Klinkhachorn, P.; Lonkar, G.

    2005-04-01

    This paper demonstrates the use of digital infrared thermography to detect subsurface defects such as debonds and delaminations in Fiber Reinforced Polymer (FRP) bridge decks. Simulated sub-surface debonds and delaminations were inserted between the wearing surface and the underlying FRP deck specimens. The infrared thermography technique was used to detect these embedded subsurface defects. The use of various cooling and heating methods, including solar radiation, was explored. Surface temperature-time curves were established for different types and sizes of subsurface defects.

  20. Pulmonary agenesis associated with dextrocardia, sternal defects, and ectopic kidney.

    PubMed

    Eroglu, Atilla; Alper, Fatih; Turkyilmaz, Atila; Karaoglanoglu, Nurettin; Okur, Adnan

    2005-12-01

    Pulmonary agenesis is a rare embryological defect, usually unilateral, and is associated with skeletal, cardiovascular, and other anomalies. A 22-month-old girl was admitted to our clinic with recurrent pulmonary infections. A chest X-ray and multidetector computed tomography (MDCT) revealed pulmonary agenesis with dextrocardia, sternal defects, and a right pelvic ectopic kidney. We report on the first known case of right-sided pulmonary agenesis combined with isolated dextrocardia, sternal defects, and an ectopic kidney. The importance of MDCT for the diagnosis of pulmonary agenesis and associated other anomalies is demonstrated.

  1. Ventricular septal defect in a houbara bustard (Chlamydotis undulata macqueenii).

    PubMed

    Bailey, T A; Kinne, J

    2001-01-01

    A ventricular septal defect was found in a juvenile captive-bred houbara bustard (Chlamydotis undulata) that died suddenly. The case history indicated that the bird had a retarded growth and maturation rate. Gross pathology demonstrated massive internal hemorrhage, an enlarged heart with an interventricular septal defect, one shrunken liver lobe, and hypoplastic kidneys. Histologically, the liver was characterized by fatty degeneration, and there was hydropic degeneration of the cardiac muscle fibers. We suggest that the occurrence of this defect led to cardiac insufficiency, which resulted in sudden death caused by hemorrhage from the liver.

  2. Investigation into distinguishing between small volumetric and crack-like defects using multi-view total focusing method images

    NASA Astrophysics Data System (ADS)

    Zhang, Jie; Barber, Tom; Nixon, Andrew; Wilcox, Paul

    2017-02-01

    In the post-processing of ultrasonic array full matrix capture (FMC) data from an immersion inspection to image a region of interest (ROI), the total focusing method (TFM) can be used to generate multiple image views for the same region through exploiting reflections off geometric features, mode conversions at interfaces and using different paths for transmitted and received waves. They are termed as the multi-view TFM (MTFM) images. In this paper, the feasibility of using MTFM images to distinguish between small volumetric and crack-like defects is investigated through the analysis of the images from various simulated and experimentally-measured FMC array data sets. It is found that the presence of a defect of a particular type will typically be observable in some or all of the views with different image amplitudes. Different types of defect have large amplitudes in different views and this can be used to classify the defect type. Finally, the use of this approach is demonstrated in the experimental inspection of samples.

  3. Enhanced capture rate for haze defects in production wafer inspection

    NASA Astrophysics Data System (ADS)

    Auerbach, Ditza; Shulman, Adi; Rozentsvige, Moshe

    2010-03-01

    Photomask degradation via haze defect formation is an increasing troublesome yield problem in the semiconductor fab. Wafer inspection is often utilized to detect haze defects due to the fact that it can be a bi-product of process control wafer inspection; furthermore, the detection of the haze on the wafer is effectively enhanced due to the multitude of distinct fields being scanned. In this paper, we demonstrate a novel application for enhancing the wafer inspection tool's sensitivity to haze defects even further. In particular, we present results of bright field wafer inspection using the on several photo layers suffering from haze defects. One way in which the enhanced sensitivity can be achieved in inspection tools is by using a double scan of the wafer: one regular scan with the normal recipe and another high sensitivity scan from which only the repeater defects are extracted (the non-repeater defects consist largely of noise which is difficult to filter). Our solution essentially combines the double scan into a single high sensitivity scan whose processing is carried out along two parallel routes (see Fig. 1). Along one route, potential defects follow the standard recipe thresholds to produce a defect map at the nominal sensitivity. Along the alternate route, potential defects are used to extract only field repeater defects which are identified using an optimal repeater algorithm that eliminates "false repeaters". At the end of the scan, the two defect maps are merged into one with optical scan images available for all the merged defects. It is important to note, that there is no throughput hit; in addition, the repeater sensitivity is increased relative to a double scan, due to a novel runtime algorithm implementation whose memory requirements are minimized, thus enabling to search a much larger number of potential defects for repeaters. We evaluated the new application on photo wafers which consisted of both random and haze defects. The evaluation procedure

  4. Light manipulation of nanoparticles in arrays of topological defects

    PubMed Central

    Kasyanyuk, D.; Pagliusi, P.; Mazzulla, A.; Reshetnyak, V.; Reznikov, Yu.; Provenzano, C.; Giocondo, M.; Vasnetsov, M.; Yaroshchuk, O.; Cipparrone, G.

    2016-01-01

    We report a strategy to assemble and manipulate nanoparticles arrays. The approach is based on the use of topological defects, namely disclination lines, created in chiral liquid crystals. The control of nanoparticle-loaded topological defects by low power light is demonstrated. Large-scale rotation, translation and deformation of quantum dots light-emitting chains is achieved by homogeneous LED illumination. Full reconfigurability and time stability make this approach attractive for future developments and applications. PMID:26882826

  5. Tuning micropillar cavity birefringence by laser induced surface defects

    SciTech Connect

    Bonato, Cristian; Ding Dapeng; Gudat, Jan; Exter, Martin P. van; Thon, Susanna; Kim, Hyochul; Petroff, Pierre M.; Bouwmeester, Dirk

    2009-12-21

    We demonstrate a technique to tune the optical properties of micropillar cavities by creating small defects on the sample surface near the cavity region with an intense focused laser beam. Such defects modify strain in the structure, changing the birefringence in a controllable way. We apply the technique to make the fundamental cavity mode polarization-degenerate and to fine tune the overall mode frequencies, as needed for applications in quantum information science.

  6. Light manipulation of nanoparticles in arrays of topological defects

    NASA Astrophysics Data System (ADS)

    Kasyanyuk, D.; Pagliusi, P.; Mazzulla, A.; Reshetnyak, V.; Reznikov, Yu.; Provenzano, C.; Giocondo, M.; Vasnetsov, M.; Yaroshchuk, O.; Cipparrone, G.

    2016-02-01

    We report a strategy to assemble and manipulate nanoparticles arrays. The approach is based on the use of topological defects, namely disclination lines, created in chiral liquid crystals. The control of nanoparticle-loaded topological defects by low power light is demonstrated. Large-scale rotation, translation and deformation of quantum dots light-emitting chains is achieved by homogeneous LED illumination. Full reconfigurability and time stability make this approach attractive for future developments and applications.

  7. Improving reticle defect disposition via fully automated lithography simulation

    NASA Astrophysics Data System (ADS)

    Mann, Raunak; Goodman, Eliot; Lao, Keith; Ha, Steven; Vacca, Anthony; Fiekowsky, Peter; Fiekowsky, Dan

    2016-03-01

    Most advanced wafer fabs have embraced complex pattern decoration, which creates numerous challenges during in-fab reticle qualification. These optical proximity correction (OPC) techniques create assist features that tend to be very close in size and shape to the main patterns as seen in Figure 1. A small defect on an assist feature will most likely have little or no impact on the fidelity of the wafer image, whereas the same defect on a main feature could significantly decrease device functionality. In order to properly disposition these defects, reticle inspection technicians need an efficient method that automatically separates main from assist features and predicts the resulting defect impact on the wafer image. Analysis System (ADAS) defect simulation system[1]. Up until now, using ADAS simulation was limited to engineers due to the complexity of the settings that need to be manually entered in order to create an accurate result. A single error in entering one of these values can cause erroneous results, therefore full automation is necessary. In this study, we propose a new method where all needed simulation parameters are automatically loaded into ADAS. This is accomplished in two parts. First we have created a scanner parameter database that is automatically identified from mask product and level names. Second, we automatically determine the appropriate simulation printability threshold by using a new reference image (provided by the inspection tool) that contains a known measured value of the reticle critical dimension (CD). This new method automatically loads the correct scanner conditions, sets the appropriate simulation threshold, and automatically measures the percentage of CD change caused by the defect. This streamlines qualification and reduces the number of reticles being put on hold, waiting for engineer review. We also present data showing the consistency and reliability of the new method, along with the impact on the efficiency of in

  8. TRW utility demonstration unit

    SciTech Connect

    Not Available

    1990-01-01

    The TRW Advanced Entrained Coal Combustor Demonstration Project consists of retrofitting Orange and Rockland (O R) Utility Corporation's Lovett Plant Unit No. 3 with four (4) slagging combustors which will allow the gas/oil unit to fire 2.5% sulfur coal. The slagging combustor process will provide NO{sub x} and SO{sub x} emissions that meet NSPS and New York State Environmental Standards. During this report period, activity continued to address the total program funding shortfall. Ideas and responsibilities for further evaluation have been put forward to reduce the shortfall. In addition, an effort aimed at gaining additional program sponsorships, was initiated.

  9. Space Research Benefits Demonstrated

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Angie Jackman, a NASA project manager in microgravity research, demonstrates the enhanced resilience of undercooled metal alloys as compared to conventional alloys. Experiments aboard the Space Shuttle helped scientists refine their understanding of the physical properties of certain metal alloys when undercooled (i.e., kept liquid below their normal solidification temperature). This new knowledge then allowed scientists to modify a terrestrial production method so they can now make limited quantities marketed under the Liquid Metal trademark. The exhibit was a part of the NASA outreach activity at AirVenture 2000 sponsored by the Experimental Aircraft Association in Oshkosh, WI.

  10. Santa Clara Demonstration Status

    SciTech Connect

    Leo, Anthony J.; Skok, Andrew J.; O'Shea, Thomas P.

    1996-08-01

    Fuel Cell Engineering Corporation (FCE) is in the fourth year of a DOE Cooperative Agreement Program (private-sector cost-shared) aimed at the demonstration of ERC's direct carbonate fuel cell (DFC) technology at full scale. FCE is a wholly owned subsidiary of Energy Research Corporation (ERC), which has been pursuing the development of the DFC for commercialization near the end of this decade. The DFC produces power directly from hydrocarbon fuels electrochemically, without the need for external reforming or intermediate mechanical conversion steps. As a result, the DFC has the potential to achieve very high efficiency with very low levels of environmental emissions. Modular DFC power plants, which can be shop-fabricated and sited near the user, are ideally suited for distributed generation, cogeneration, industrial, and defense applications. This project is an integral part of the ERC effort to commercialize the technology to serve these applications. Potential users of the commercial DFC power plant under development at ERC will require that the technology be demonstrated at or near the full scale of the commercial products. The objective of the Santa Clara Demonstration Project (SCDP) is to provide the first such demonstration of the technology. The approach ERC has taken in the commercialization of the DFC is described in detail elsewhere [1]. Briefly, an aggressive core technology development program is in place which is focused by ongoing contact with customers and vendors to optimize the design of the commercial power plant. ERC has selected a 2.85 MW power plant unit for initial market entry. Two ERC subsidiaries are supporting the commercialization effort: The Fuel Cell Manufacturing Corporation (FCMC) and the Fuel Cell Engineering Corporation (FCE). FCMC manufactures carbonate stacks and multi-stack modules, currently from its manufacturing facility in Torrington, CT. FCE is responsible for power plant design, integration of all subsystems, sales

  11. Exploration Medical System Demonstration

    NASA Technical Reports Server (NTRS)

    Rubin, D. A.; Watkins, S. D.

    2014-01-01

    BACKGROUND: Exploration class missions will present significant new challenges and hazards to the health of the astronauts. Regardless of the intended destination, beyond low Earth orbit a greater degree of crew autonomy will be required to diagnose medical conditions, develop treatment plans, and implement procedures due to limited communications with ground-based personnel. SCOPE: The Exploration Medical System Demonstration (EMSD) project will act as a test bed on the International Space Station (ISS) to demonstrate to crew and ground personnel that an end-to-end medical system can assist clinician and non-clinician crew members in optimizing medical care delivery and data management during an exploration mission. Challenges facing exploration mission medical care include limited resources, inability to evacuate to Earth during many mission phases, and potential rendering of medical care by non-clinicians. This system demonstrates the integration of medical devices and informatics tools for managing evidence and decision making and can be designed to assist crewmembers in nominal, non-emergent situations and in emergent situations when they may be suffering from performance decrements due to environmental, physiological or other factors. PROJECT OBJECTIVES: The objectives of the EMSD project are to: a. Reduce or eliminate the time required of an on-orbit crew and ground personnel to access, transfer, and manipulate medical data. b. Demonstrate that the on-orbit crew has the ability to access medical data/information via an intuitive and crew-friendly solution to aid in the treatment of a medical condition. c. Develop a common data management framework that can be ubiquitously used to automate repetitive data collection, management, and communications tasks for all activities pertaining to crew health and life sciences. d. Ensure crew access to medical data during periods of restricted ground communication. e. Develop a common data management framework that

  12. West Valley Demonstration Project

    SciTech Connect

    Not Available

    1991-01-01

    Under the West Valley Demonstration Project Act, Public Law 96-368, liquid high-level radioactive waste stored at the Western New York Nuclear Service Center in West Valley, New York, is to be solidified (vitrified) in borosilicate glass and transported to a federal repository for geologic disposal. This waste material resulted from spent nuclear fuel reprocessing operations conducted between 1966 and 1972. Project costs are shared by the US Department of Energy (90 percent) and the New York State Energy Research and Development Authority (10 percent). The site on which the Project is located is owned by New York State. This report is an overview of West Valley's plans and accomplishments.

  13. NAVAJO ELECTRIFICATION DEMONSTRATION PROJECT

    SciTech Connect

    Terry W. Battiest

    2008-06-11

    The Navajo Electrification Demonstration Project (NEDP) is a multi-year project which addresses the electricity needs of the unserved and underserved Navajo Nation, the largest American Indian tribe in the United States. The program serves to cumulatively provide off-grid electricty for families living away from the electricty infrastructure, line extensions for unserved families living nearby (less than 1/2 mile away from) the electricity, and, under the current project called NEDP-4, the construction of a substation to increase the capacity and improve the quality of service into the central core region of the Navajo Nation.

  14. Single Molecule Investigation of Kinesin-1 Motility Using Engineered Microtubule Defects

    PubMed Central

    Gramlich, Michael W.; Conway, Leslie; Liang, Winnie H.; Labastide, Joelle A.; King, Stephen J.; Xu, Jing; Ross, Jennifer L.

    2017-01-01

    The structure of the microtubule is tightly regulated in cells via a number of microtubule associated proteins and enzymes. Microtubules accumulate structural defects during polymerization, and defect size can further increase under mechanical stresses. Intriguingly, microtubule defects have been shown to be targeted for removal via severing enzymes or self-repair. The cell’s control in defect removal suggests that defects can impact microtubule-based processes, including molecular motor-based intracellular transport. We previously demonstrated that microtubule defects influence cargo transport by multiple kinesin motors. However, mechanistic investigations of the observed effects remained challenging, since defects occur randomly during polymerization and are not directly observable in current motility assays. To overcome this challenge, we used end-to-end annealing to generate defects that are directly observable using standard epi-fluorescence microscopy. We demonstrate that the annealed sites recapitulate the effects of polymerization-derived defects on multiple-motor transport, and thus represent a simple and appropriate model for naturally-occurring defects. We found that single kinesins undergo premature dissociation, but not preferential pausing, at the annealed sites. Our findings provide the first mechanistic insight to how defects impact kinesin-based transport. Preferential dissociation on the single-molecule level has the potential to impair cargo delivery at locations of microtubule defect sites in vivo. PMID:28287156

  15. Single Molecule Investigation of Kinesin-1 Motility Using Engineered Microtubule Defects

    NASA Astrophysics Data System (ADS)

    Gramlich, Michael W.; Conway, Leslie; Liang, Winnie H.; Labastide, Joelle A.; King, Stephen J.; Xu, Jing; Ross, Jennifer L.

    2017-03-01

    The structure of the microtubule is tightly regulated in cells via a number of microtubule associated proteins and enzymes. Microtubules accumulate structural defects during polymerization, and defect size can further increase under mechanical stresses. Intriguingly, microtubule defects have been shown to be targeted for removal via severing enzymes or self-repair. The cell’s control in defect removal suggests that defects can impact microtubule-based processes, including molecular motor-based intracellular transport. We previously demonstrated that microtubule defects influence cargo transport by multiple kinesin motors. However, mechanistic investigations of the observed effects remained challenging, since defects occur randomly during polymerization and are not directly observable in current motility assays. To overcome this challenge, we used end-to-end annealing to generate defects that are directly observable using standard epi-fluorescence microscopy. We demonstrate that the annealed sites recapitulate the effects of polymerization-derived defects on multiple-motor transport, and thus represent a simple and appropriate model for naturally-occurring defects. We found that single kinesins undergo premature dissociation, but not preferential pausing, at the annealed sites. Our findings provide the first mechanistic insight to how defects impact kinesin-based transport. Preferential dissociation on the single-molecule level has the potential to impair cargo delivery at locations of microtubule defect sites in vivo.

  16. Solar Thermal Demonstration Project

    SciTech Connect

    Biesinger, K; Cuppett, D; Dyer, D

    2012-01-30

    HVAC Retrofit and Energy Efficiency Upgrades at Clark High School, Las Vegas, Nevada The overall objectives of this project are to increase usage of alternative/renewable fuels, create a better and more reliable learning environment for the students, and reduce energy costs. Utilizing the grant resources and local bond revenues, the District proposes to reduce electricity consumption by installing within the existing limited space, one principal energy efficient 100 ton adsorption chiller working in concert with two 500 ton electric chillers. The main heating source will be primarily from low nitrogen oxide (NOX), high efficiency natural gas fired boilers. With the use of this type of chiller, the electric power and cost requirements will be greatly reduced. To provide cooling to the information technology centers and equipment rooms of the school during off-peak hours, the District will install water source heat pumps. In another measure to reduce the cooling requirements at Clark High School, the District will replace single pane glass and metal panels with Kalwall building panels. An added feature of the Kalwall system is that it will allow for natural day lighting in the student center. This system will significantly reduce thermal heat/cooling loss and control solar heat gain, thus delivering significant savings in heating ventilation and air conditioning (HVAC) costs.

  17. Facts about Ventricular Septal Defect

    MedlinePlus

    ... Living With Heart Defects Data & Statistics Tracking & Research Articles & Key Findings Free Materials Multimedia and Tools Links to Other Websites Information For... Media Policy Makers Facts about Ventricular Septal Defect Language: English Español (Spanish) Recommend on Facebook Tweet Share Compartir ...

  18. Congenital Heart Defects (For Parents)

    MedlinePlus

    ... of the heart or its surrounding structures, include: Aortic Stenosis In aortic stenosis, the aortic valve is stiffened and has a narrowed opening. ... actually a combination of four heart defects: pulmonary stenosis; a thickened ... septal defect); and an aorta that can receive blood from both the left ...

  19. Feature analysis and classification of manufacturing signatures based on semiconductor wafermaps

    SciTech Connect

    Tobin, K.W.; Gleason, S.S.; Karnowski, T.P.; Cohen, S.L.

    1997-02-01

    Automated tools for semiconductor wafer defect analysis are becoming more necessary as device densities and wafer sizes continue to increase. Trends towards larger wafer formats and smaller critical dimensions have caused an exponential increase in the volume of defect data which must be analyzed and stored. To accommodate these changing factors, automatic analysis tools are required that can efficiently and robustly process the increasing amounts of data, and thus quickly characterize manufacturing processes and accelerate yield learning. During the first year of this cooperative research project between SEMATECH and the Oak Ridge National Laboratory, a robust methodology for segmenting signature events prior to feature analysis and classification was developed. Based on the results of this segmentation procedure, a feature measurement strategy has been designed based on interviews with process engineers coupled with the analysis of approximately 1500 electronic wafermap files. In this paper, the authors represent an automated procedure to rank and select relevant features for use with a fuzzy pair-wise classifier and give examples of the efficacy of the approach taken. Results of the feature selection process are given for two uniquely different types of class data to demonstrate a general improvement in classifier performance.

  20. SSME Key Operations Demonstration

    NASA Technical Reports Server (NTRS)

    Anderson, Brian; Bradley, Michael; Ives, Janet

    1997-01-01

    A Space Shuttle Main Engine (SSME) test program was conducted between August 1995 and May 1996 using the Technology Test Bed (TTB) Engine. SSTO vehicle studies have indicated that increases in the propulsion system operating range can save significant weight and cost at the vehicle level. This test program demonstrated the ability of the SSME to accommodate a wide variation in safe operating ranges and therefore its applicability to the SSTO mission. A total of eight tests were completed with four at Marshall Space Flight Center's Advanced Engine Test Facility and four at the Stennis Space Center (SSC) A-2 attitude test stand. Key demonstration objectives were: 1) Mainstage operation at 5.4 to 6.9 mixture ratio; 2) Nominal engine start with significantly reduced engine inlet pressures of 50 psia LOX and 38 psia fuel; and 3) Low power level operation at 17%, 22%, 27%, 40%, 45%, and 50% of Rated Power Level. Use of the highly instrumented TTB engine for this test series has afforded the opportunity to study in great detail engine system operation not possible with a standard SSME and has significantly contributed to a greater understanding of the capabilities of the SSME and liquid rocket engines in general.

  1. Puget Sound telecommuting demonstration

    SciTech Connect

    Quaid, M.; Heifetz, L.; Farley, M.; Christensen, D.; Ulberg, C.; Gordon, A.; Spain, D.; Whitaker, B.

    1992-04-01

    This report discusses the Puget Sound Telecommuting demonstration project. This is a part-time work and transportation alternative that substitutes the normal work commute with the choice of working at home or at an office close to home. According to Link Resources, a research and consulting firm located in New York, there were 4.6 million part-time home telecommuters in the United States in 1991. This figure, which included only company employees who work at home during normal business hours, is up from 3.4 million in 1990, an increase of 35 percent in one year. Part-time telecommuters average 2.5 days per week at home. (There are also about 876,000 full-time telecommuters in the US.) The study done by Link Resources estimates that 4.5 percent of the civilian work force age 18 or older is telecommuting. The Washington State Energy Office (WSEO) began exploring telecommuting as an alternate route to work for Washington, first through The Governor`s Conference on Telecommuting in June 1989. The conference raised corporate and government awareness of telecommuting, and set the stage for further investigation. In 1990, WSEO launched the Puget Sound Telecommuting Demonstration to explore the environmental, organizational, and personal sides of telecommuting. This report presents the interim research results.

  2. Puget Sound telecommuting demonstration

    SciTech Connect

    Quaid, M.; Heifetz, L.; Farley, M.; Christensen, D. ); Ulberg, C.; Gordon, A.; Spain, D.; Whitaker, B. )

    1992-04-01

    This report discusses the Puget Sound Telecommuting demonstration project. This is a part-time work and transportation alternative that substitutes the normal work commute with the choice of working at home or at an office close to home. According to Link Resources, a research and consulting firm located in New York, there were 4.6 million part-time home telecommuters in the United States in 1991. This figure, which included only company employees who work at home during normal business hours, is up from 3.4 million in 1990, an increase of 35 percent in one year. Part-time telecommuters average 2.5 days per week at home. (There are also about 876,000 full-time telecommuters in the US.) The study done by Link Resources estimates that 4.5 percent of the civilian work force age 18 or older is telecommuting. The Washington State Energy Office (WSEO) began exploring telecommuting as an alternate route to work for Washington, first through The Governor's Conference on Telecommuting in June 1989. The conference raised corporate and government awareness of telecommuting, and set the stage for further investigation. In 1990, WSEO launched the Puget Sound Telecommuting Demonstration to explore the environmental, organizational, and personal sides of telecommuting. This report presents the interim research results.

  3. PFBC Utility Demonstration Project

    SciTech Connect

    Not Available

    1992-11-01

    This report provides a summary of activities by American Electric Power Service Corporation during the first budget period of the PFBC Utility Demonstration Project. In April 1990, AEP signed a Cooperative Agreement with the US Department of Energy to repower the Philip Sporn Plant, Units 3 4 in New Haven, West Virginia, with a 330 KW PFBC plant. The purpose of the program was to demonstrate and verify PFBC in a full-scale commercial plant. The technical and cost baselines of the Cooperative Agreement were based on a preliminary engineering and design and a cost estimate developed by AEP subsequent to AEP's proposal submittal in May 1988, and prior to the signing of the Cooperative Agreement. The Statement of Work in the first budget period of the Cooperative Agreement included a task to develop a preliminary design and cost estimate for erecting a Greenfield plant and to conduct a comparison with the repowering option. The comparative assessment of the options concluded that erecting a Greenfield plant rather than repowering the existing Sporn Plant could be the technically and economically superior alternative. The Greenfield plant would have a capacity of 340 MW. The ten additional MW output is due to the ability to better match the steam cycle to the PFBC system with a new balance of plant design. In addition to this study, the conceptual design of the Sporn Repowering led to several items which warranted optimization studies with the goal to develop a more cost effective design.

  4. BEAM Technology Flight Demonstration

    NASA Technical Reports Server (NTRS)

    Wang, David

    2005-01-01

    As technologies advance, their growing complexity makes them harder to maintain. Detection methods for isolating and identifying impending problems are needed to balance this complexity. Through comparison of signal pairs from onboard sensors, the Beacon-based Exception Analysis For Multimissions (BEAM) algorithm can identify and help classify deviations in system operation from a data-trained statistical model. The goal of this task is to mature BEAM and validate its performance on a flying test bed. A series of F-18 flight demonstrations with BEAM monitoring engine parameters in real time was used to demonstrate in-the-field readiness. Captured F-18 and simulated F-18 engine data were used in model creation and training. The algorithm was then ported to the embedded system with a data buffering, file writing, and data-time-stamp monitoring shell to reduce the impact of embedded system faults on BEAM'S ability to correctly identify engine faults. Embedded system testing identified hardware related restrictions and contributed to iterative improvements in the code's runtime performance. The system was flown with forced engine flameouts and other pilot induced faults to simulate operation out of the norm. Successful detection of these faults, confirmed through post-flight data analysis, helped BEAM achieve TRL6.

  5. Residential Transactive Control Demonstration

    SciTech Connect

    Widergren, Steven E.; Fuller, Jason C.; Marinovici, Maria C.; Somani, Abhishek

    2014-02-19

    Arguably the most exciting aspect of the smart grid vision is the full participation of end-use resources with all forms of generation and energy storage in the reliable and efficient operation of an electric power system. Engaging all of these resources in a collaborative manner that respects the objectives of each resource, is sensitive to the system and local constraints of electricity flow, and scales to the large number of devices and systems participating is a grand challenge. Distributed decision-making system approaches have been presented and experimentation is underway. This paper reports on the preliminary findings of a residential demand response demonstration that uses the bidding transactions of supply and end-use air conditioning resources communicating with a real-time, 5 minute market to balance the various needs of the participants on a distribution feeder. The nature of the demonstration, the value streams being explored, and the operational scenarios implemented to characterize the system response are summarized along with preliminary findings.

  6. Smart Grid Demonstration Project

    SciTech Connect

    Miller, Craig; Carroll, Paul; Bell, Abigail

    2015-03-11

    The National Rural Electric Cooperative Association (NRECA) organized the NRECA-U.S. Department of Energy (DOE) Smart Grid Demonstration Project (DE-OE0000222) to install and study a broad range of advanced smart grid technologies in a demonstration that spanned 23 electric cooperatives in 12 states. More than 205,444 pieces of electronic equipment and more than 100,000 minor items (bracket, labels, mounting hardware, fiber optic cable, etc.) were installed to upgrade and enhance the efficiency, reliability, and resiliency of the power networks at the participating co-ops. The objective of this project was to build a path for other electric utilities, and particularly electrical cooperatives, to adopt emerging smart grid technology when it can improve utility operations, thus advancing the co-ops’ familiarity and comfort with such technology. Specifically, the project executed multiple subprojects employing a range of emerging smart grid technologies to test their cost-effectiveness and, where the technology demonstrated value, provided case studies that will enable other electric utilities—particularly electric cooperatives— to use these technologies. NRECA structured the project according to the following three areas: Demonstration of smart grid technology; Advancement of standards to enable the interoperability of components; and Improvement of grid cyber security. We termed these three areas Technology Deployment Study, Interoperability, and Cyber Security. Although the deployment of technology and studying the demonstration projects at coops accounted for the largest portion of the project budget by far, we see our accomplishments in each of the areas as critical to advancing the smart grid. All project deliverables have been published. Technology Deployment Study: The deliverable was a set of 11 single-topic technical reports in areas related to the listed technologies. Each of these reports has already been submitted to DOE, distributed to co-ops, and

  7. Improved tensile and buckling behavior of defected carbon nanotubes utilizing boron nitride coating - A molecular dynamic study

    NASA Astrophysics Data System (ADS)

    Badjian, H.; Setoodeh, A. R.

    2017-02-01

    Synthesizing inorganic nanostructures such as boron nitride nanotubes (BNNTs) have led to immense studies due to their many interesting functional features such as piezoelectricity, high temperature resistance to oxygen, electrical insulation, high thermal conductivity and very long lengths as physical features. In order to utilize the superior properties of pristine and defected carbon nanotubes (CNTs), a hybrid nanotube is proposed in this study by forming BNNTs surface coating on the CNTs. The benefits of such coating on the tensile and buckling behavior of single-walled CNTs (SWCNTs) are illustrated through molecular dynamics (MD) simulations of the resulted nanostructures during the deformation. The AIREBO and Tersoff-Brenner potentials are employed to model the interatomic forces between the carbon and boron nitride atoms, respectively. The effects of chiral indices, aspect ratio, presence of mono-vacancy defects and coating dimension on coated/non-coated CNTs are examined. It is demonstrated that the coated defective CNTs exhibit remarkably enhanced ultimate strength, buckling load capacity and Young's modulus. The proposed coating not only enhances the mechanical properties of the resulted nanostructure, but also conceals it from few external factors impacting the behavior of the CNT such as humidity and high temperature.

  8. Classification of weld defect based on information fusion technology for radiographic testing system.

    PubMed

    Jiang, Hongquan; Liang, Zeming; Gao, Jianmin; Dang, Changying

    2016-03-01

    Improving the efficiency and accuracy of weld defect classification is an important technical problem in developing the radiographic testing system. This paper proposes a novel weld defect classification method based on information fusion technology, Dempster-Shafer evidence theory. First, to characterize weld defects and improve the accuracy of their classification, 11 weld defect features were defined based on the sub-pixel level edges of radiographic images, four of which are presented for the first time in this paper. Second, we applied information fusion technology to combine different features for weld defect classification, including a mass function defined based on the weld defect feature information and the quartile-method-based calculation of standard weld defect class which is to solve a sample problem involving a limited number of training samples. A steam turbine weld defect classification case study is also presented herein to illustrate our technique. The results show that the proposed method can increase the correct classification rate with limited training samples and address the uncertainties associated with weld defect classification.

  9. Classification of weld defect based on information fusion technology for radiographic testing system

    NASA Astrophysics Data System (ADS)

    Jiang, Hongquan; Liang, Zeming; Gao, Jianmin; Dang, Changying

    2016-03-01

    Improving the efficiency and accuracy of weld defect classification is an important technical problem in developing the radiographic testing system. This paper proposes a novel weld defect classification method based on information fusion technology, Dempster-Shafer evidence theory. First, to characterize weld defects and improve the accuracy of their classification, 11 weld defect features were defined based on the sub-pixel level edges of radiographic images, four of which are presented for the first time in this paper. Second, we applied information fusion technology to combine different features for weld defect classification, including a mass function defined based on the weld defect feature information and the quartile-method-based calculation of standard weld defect class which is to solve a sample problem involving a limited number of training samples. A steam turbine weld defect classification case study is also presented herein to illustrate our technique. The results show that the proposed method can increase the correct classification rate with limited training samples and address the uncertainties associated with weld defect classification.

  10. Transport on a lattice with dynamical defects.

    PubMed

    Turci, Francesco; Parmeggiani, Andrea; Pitard, Estelle; Romano, M Carmen; Ciandrini, Luca

    2013-01-01

    Many transport processes in nature take place on substrates, often considered as unidimensional lanes. These unidimensional substrates are typically nonstatic: Affected by a fluctuating environment, they can undergo conformational changes. This is particularly true in biological cells, where the state of the substrate is often coupled to the active motion of macromolecular complexes, such as motor proteins on microtubules or ribosomes on mRNAs, causing new interesting phenomena. Inspired by biological processes such as protein synthesis by ribosomes and motor protein transport, we introduce the concept of localized dynamical sites coupled to a driven lattice gas dynamics. We investigate the phenomenology of transport in the presence of dynamical defects and find a regime characterized by an intermittent current and subject to severe finite-size effects. Our results demonstrate the impact of the regulatory role of the dynamical defects in transport not only in biology but also in more general contexts.

  11. Photopsia and a temporal visual field defect.

    PubMed

    Marsiglia, Marcela; Odel, Jeffery G; Rudich, Danielle S; Tsang, Stephen H; Plant, Gordon T

    2016-01-01

    A 30-year-old woman presented with intermittent photopsia, a temporal visual field defect below the horizontal in her left eye, and flu-like symptoms. Slit-lamp and fundus examinations were unremarkable. Humphrey 30-2 threshold perimetry and 120-point screening visual field demonstrated blind spot enlargement of the left eye and a normal field in the right eye. Fundus autofluorescence, optical coherence tomography of the macula, full-field electroretinogram, electrooculogram, and multifocal electroretinogram were normal. Swept-source optical coherence tomography scan of the left optic nerve showed an intact outer retina, a remarkably thinned nerve fiber layer nasally, and peripapillary vitreous traction. Goldmann kinetic perimetry revealed a sector-shaped dense defect breaking out from the blind spot to the temporal periphery just below the horizontal in the left eye. The patient had nasal hypoplasia of the optic nerve and peripapillary vitreous traction.

  12. Complete corrosion inhibition through graphene defect passivation.

    PubMed

    Hsieh, Ya-Ping; Hofmann, Mario; Chang, Kai-Wen; Jhu, Jian Gang; Li, Yuan-Yao; Chen, Kuang Yao; Yang, Chang Chung; Chang, Wen-Sheng; Chen, Li-Chyong

    2014-01-28

    Graphene is expected to enable superior corrosion protection due to its impermeability and chemical inertness. Previous reports, however, demonstrate limited corrosion inhibition and even corrosion enhancement of graphene on metal surfaces. To enable the reliable and complete passivation, the origin of the low inhibition efficiency of graphene was investigated. Combining electrochemical and morphological characterization techniques, nanometer-sized structural defects in chemical vapor deposition grown graphene were found to be the cause for the limited passivation effect. Extremely fast mass transport on the order of meters per second both across and parallel to graphene layers results in an inhibition efficiency of only ∼50% for Cu covered with up to three graphene layers. Through selective passivation of the defects by atomic layer deposition (ALD) an enhanced corrosion protection of more than 99% was achieved, which compares favorably with commercial corrosion protection methods.

  13. Topological Point Defects in Relaxor Ferroelectrics

    NASA Astrophysics Data System (ADS)

    Nahas, Y.; Prokhorenko, S.; Kornev, I.; Bellaiche, L.

    2016-03-01

    First-principles-based effective Hamiltonian simulations are used to reveal the hidden connection between topological defects (hedgehogs and antihedgehogs) and relaxor behavior. Such defects are discovered to predominantly lie at the border of polar nanoregions in both Ba (Zr0.5 Ti0.5 )O3 (BZT) and Pb (Sc0.5 Nb0.5 )O3 (PSN) systems, and the temperature dependency of their density allows us to distinguish between noncanonical (PSN) and canonical (BZT) relaxor behaviors (via the presence or absence of a crossing of a percolation threshold). This density also possesses an inflection point at precisely the temperature for which the dielectric response peaks. Moreover, hedgehogs and antihedgehogs are found to be mobile excitations, and the dynamical nature of their annihilation is demonstrated (using simple hydrodynamical arguments) to follows laws, such as those of Vogel-Fulcher and Arrhenius, that are characteristic of dipolar relaxation kinetics of relaxor ferroelectrics.

  14. Defective twin boundaries in nanotwinned metals.

    PubMed

    Wang, Y Morris; Sansoz, Frederic; LaGrange, Thomas; Ott, Ryan T; Marian, Jaime; Barbee, Troy W; Hamza, Alex V

    2013-08-01

    Coherent twin boundaries (CTBs) are widely described, both theoretically and experimentally, as perfect interfaces that play a significant role in a variety of materials. Although the ability of CTBs in strengthening, maintaining the ductility and minimizing the electron scattering is well documented, most of our understanding of the origin of these properties relies on perfect-interface assumptions. Here we report experiments and simulations demonstrating that as-grown CTBs in nanotwinned copper are inherently defective with kink-like steps and curvature, and that these imperfections consist of incoherent segments and partial dislocations. We further show that these defects play a crucial role in the deformation mechanisms and mechanical behaviour of nanotwinned copper. Our findings offer a view of the structure of CTBs that is largely different from that in the literature, and underscore the significance of imperfections in nanotwin-strengthened materials.

  15. Transport on a lattice with dynamical defects

    NASA Astrophysics Data System (ADS)

    Turci, Francesco; Parmeggiani, Andrea; Pitard, Estelle; Romano, M. Carmen; Ciandrini, Luca

    2013-01-01

    Many transport processes in nature take place on substrates, often considered as unidimensional lanes. These unidimensional substrates are typically nonstatic: Affected by a fluctuating environment, they can undergo conformational changes. This is particularly true in biological cells, where the state of the substrate is often coupled to the active motion of macromolecular complexes, such as motor proteins on microtubules or ribosomes on mRNAs, causing new interesting phenomena. Inspired by biological processes such as protein synthesis by ribosomes and motor protein transport, we introduce the concept of localized dynamical sites coupled to a driven lattice gas dynamics. We investigate the phenomenology of transport in the presence of dynamical defects and find a regime characterized by an intermittent current and subject to severe finite-size effects. Our results demonstrate the impact of the regulatory role of the dynamical defects in transport not only in biology but also in more general contexts.

  16. Holographic Chern-Simons defects

    DOE PAGES

    Fujita, Mitsutoshi; Melby-Thompson, Charles M.; Meyer, René; ...

    2016-06-28

    Here, we study SU(N ) Yang-Mills-Chern-Simons theory in the presence of defects that shift the Chern-Simons level from a holographic point of view by embedding the system in string theory. The model is a D3-D7 system in Type IIB string theory, whose gravity dual is given by the AdS soliton background with probe D7 branes attaching to the AdS boundary along the defects. We holographically renormalize the free energy of the defect system with sources, from which we obtain the correlation functions for certain operators naturally associated to these defects. We find interesting phase transitions when the separation of themore » defects as well as the temperature are varied. We also discuss some implications for the Fractional Quantum Hall Effect and for 2-dimensional QCD.« less

  17. Global topological k-defects

    SciTech Connect

    Babichev, E.

    2006-10-15

    We consider global topological defects in symmetry-breaking models with a noncanonical kinetic term. Apart from a mass parameter entering the potential, one additional dimensional parameter arises in such models - a kinetic mass. The properties of defects in these models are quite different from standard global domain walls, vortices, and monopoles, if their kinetic mass scale is smaller than their symmetry-breaking scale. In particular, depending on the concrete form of the kinetic term, the typical size of such a defect can be either much larger or much smaller than the size of a standard defect with the same potential term. The characteristic mass of a nonstandard defect, which might have been formed during a phase transition in the early universe, depends on both the temperature of a phase transition and the kinetic mass.

  18. Holographic Chern-Simons defects

    NASA Astrophysics Data System (ADS)

    Fujita, Mitsutoshi; Melby-Thompson, Charles M.; Meyer, René; Sugimoto, Shigeki

    2016-06-01

    We study SU( N ) Yang-Mills-Chern-Simons theory in the presence of defects that shift the Chern-Simons level from a holographic point of view by embedding the system in string theory. The model is a D3-D7 system in Type IIB string theory, whose gravity dual is given by the AdS soliton background with probe D7 branes attaching to the AdS boundary along the defects. We holographically renormalize the free energy of the defect system with sources, from which we obtain the correlation functions for certain operators naturally associated to these defects. We find interesting phase transitions when the separation of the defects as well as the temperature are varied. We also discuss some implications for the Fractional Quantum Hall Effect and for 2-dimensional QCD.

  19. Holographic Chern-Simons defects

    SciTech Connect

    Fujita, Mitsutoshi; Melby-Thompson, Charles M.; Meyer, René; Sugimoto, Shigeki

    2016-06-28

    Here, we study SU(N ) Yang-Mills-Chern-Simons theory in the presence of defects that shift the Chern-Simons level from a holographic point of view by embedding the system in string theory. The model is a D3-D7 system in Type IIB string theory, whose gravity dual is given by the AdS soliton background with probe D7 branes attaching to the AdS boundary along the defects. We holographically renormalize the free energy of the defect system with sources, from which we obtain the correlation functions for certain operators naturally associated to these defects. We find interesting phase transitions when the separation of the defects as well as the temperature are varied. We also discuss some implications for the Fractional Quantum Hall Effect and for 2-dimensional QCD.

  20. Toward Intelligent Software Defect Detection

    NASA Technical Reports Server (NTRS)

    Benson, Markland J.

    2011-01-01

    Source code level software defect detection has gone from state of the art to a software engineering best practice. Automated code analysis tools streamline many of the aspects of formal code inspections but have the drawback of being difficult to construct and either prone to false positives or severely limited in the set of defects that can be detected. Machine learning technology provides the promise of learning software defects by example, easing construction of detectors and broadening the range of defects that can be found. Pinpointing software defects with the same level of granularity as prominent source code analysis tools distinguishes this research from past efforts, which focused on analyzing software engineering metrics data with granularity limited to that of a particular function rather than a line of code.

  1. Antisite defects at oxide interfaces

    NASA Astrophysics Data System (ADS)

    Chen, Hanghui; Millis, Andrew

    We use ab initio calculations to estimate formation energies of cation (transition metal) antisite defects at oxide interfaces and to understand the basic physical effects that drive or suppress the formation of these defects. We find that antisite defects are favored in systems with substantial charge transfer across the interface, while Jahn-Teller distortions and itinerant ferromagnetism can prevent antisite defects and help stabilize atomically sharp interfaces. Our results enable identification of classes of systems that are more and less susceptible to the formation of antisite defects and motivate a range of experimental studies and further theoretical calculations to further explicate the oxide interface systems. This research was supported by National Science Foundation under Grant No. DMR-1120296 (H. Chen) and DOE-ER-046169 (A. J. Millis).

  2. [Electron microscopic study of wedge-shaped defects of teeth on initial stage].

    PubMed

    Makeeva, I M; Biakova, S F; Chuev, V P; Sheveliuk, Iu V

    2009-01-01

    The aim of thes; study was to observe initial stage of wedge-shaped defects under scanning electron microscopy without prior samples preparation. There were revealed special features of structure of enamel and cement at initial stage of wedge-shaped defects in comparison to normal tissues.

  3. Electrodynamic Dust Shield Demonstrator

    NASA Technical Reports Server (NTRS)

    Stankie, Charles G.

    2013-01-01

    The objective of the project was to design and manufacture a device to demonstrate a new technology developed by NASA's Electrostatics and Surface Physics Laboratory. The technology itself is a system which uses magnetic principles to remove regolith dust from its surface. This project was to create an enclosure that will be used to demonstrate the effectiveness of the invention to The Office of the Chief Technologist. ONE of the most important challenges of space exploration is actually caused by something very small and seemingly insignificant. Dust in space, most notably on the moon and Mars, has caused many unforeseen issues. Dirt and dust on Earth, while a nuisance, can be easily cleaned and kept at bay. However, there is considerably less weathering and erosion in space. As a result, the microscopic particles are extremely rough and abrasive. They are also electrostatically charged, so they cling to everything they make contact with. This was first noted to be a major problem during the Apollo missions. Dust would stick to the spacesuits, and could not be wiped off as predicted. Dust was brought back into the spacecraft, and was even inhaled by astronauts. This is a major health hazard. Atmospheric storms and other events can also cause dust to coat surfaces of spacecraft. This can cause abrasive damage to the craft. The coating can also reduce the effectiveness of thermal insulation and solar panels.' A group of engineers at Kennedy Space Center's Electrostatics and Surface Physics Laboratory have developed a new technology, called the Electrodynamic Dust Shield, to help alleviate these problems. It is based off of the electric curtain concept developed at NASA in 1967. "The EDS is an active dust mitigation technology that uses traveling electric fields to transport electrostatically charged dust particles along surfaces. To generate the traveling electric fields, the EDS consists of a multilayer dielectric coating with an embedded thin electrode grid

  4. Frequency Optimization for Enhancement of Surface Defect Classification Using the Eddy Current Technique.

    PubMed

    Fan, Mengbao; Wang, Qi; Cao, Binghua; Ye, Bo; Sunny, Ali Imam; Tian, Guiyun

    2016-05-07

    Eddy current testing is quite a popular non-contact and cost-effective method for nondestructive evaluation of product quality and structural integrity. Excitation frequency is one of the key performance factors for defect characterization. In the literature, there are many interesting papers dealing with wide spectral content and optimal frequency in terms of detection sensitivity. However, research activity on frequency optimization with respect to characterization performances is lacking. In this paper, an investigation into optimum excitation frequency has been conducted to enhance surface defect classification performance. The influences of excitation frequency for a group of defects were revealed in terms of detection sensitivity, contrast between defect features, and classification accuracy using kernel principal component analysis (KPCA) and a support vector machine (SVM). It is observed that probe signals are the most sensitive on the whole for a group of defects when excitation frequency is set near the frequency at which maximum probe signals are retrieved for the largest defect. After the use of KPCA, the margins between the defect features are optimum from the perspective of the SVM, which adopts optimal hyperplanes for structure risk minimization. As a result, the best classification accuracy is obtained. The main contribution is that the influences of excitation frequency on defect characterization are interpreted, and experiment-based procedures are proposed to determine the optimal excitation frequency for a group of defects rather than a single defect with respect to optimal characterization performances.

  5. Frequency Optimization for Enhancement of Surface Defect Classification Using the Eddy Current Technique

    PubMed Central

    Fan, Mengbao; Wang, Qi; Cao, Binghua; Ye, Bo; Sunny, Ali Imam; Tian, Guiyun

    2016-01-01

    Eddy current testing is quite a popular non-contact and cost-effective method for nondestructive evaluation of product quality and structural integrity. Excitation frequency is one of the key performance factors for defect characterization. In the literature, there are many interesting papers dealing with wide spectral content and optimal frequency in terms of detection sensitivity. However, research activity on frequency optimization with respect to characterization performances is lacking. In this paper, an investigation into optimum excitation frequency has been conducted to enhance surface defect classification performance. The influences of excitation frequency for a group of defects were revealed in terms of detection sensitivity, contrast between defect features, and classification accuracy using kernel principal component analysis (KPCA) and a support vector machine (SVM). It is observed that probe signals are the most sensitive on the whole for a group of defects when excitation frequency is set near the frequency at which maximum probe signals are retrieved for the largest defect. After the use of KPCA, the margins between the defect features are optimum from the perspective of the SVM, which adopts optimal hyperplanes for structure risk minimization. As a result, the best classification accuracy is obtained. The main contribution is that the influences of excitation frequency on defect characterization are interpreted, and experiment-based procedures are proposed to determine the optimal excitation frequency for a group of defects rather than a single defect with respect to optimal characterization performances. PMID:27164112

  6. Jennings Demonstration PLant

    SciTech Connect

    Russ Heissner

    2010-08-31

    Verenium operated a demonstration plant with a capacity to produce 1.4 million gallons of cellulosic ethanol from agricultural resiues for about two years. During this time, the plant was able to evaluate the technical issues in producing ethanol from three different cellulosic feedstocks, sugar cane bagasse, energy cane, and sorghum. The project was intended to develop a better understanding of the operating parameters that would inform a commercial sized operation. Issues related to feedstock variability, use of hydrolytic enzymes, and the viability of fermentative organisms were evaluated. Considerable success was achieved with pretreatment processes and use of enzymes but challenges were encountered with feedstock variability and fermentation systems. Limited amounts of cellulosic ethanol were produced.

  7. Fusion Power Demonstration III

    SciTech Connect

    Lee, J.D.

    1985-07-01

    This is the third in the series of reports covering the Fusion Power Demonstration (FPD) design study. This volume considers the FPD-III configuration that incorporates an octopole end plug. As compared with the quadrupole end-plugged designs of FPD-I and FPD-II, this octopole configuration reduces the number of end cell magnets and shortens the minimum ignition length of the central cell. The end-cell plasma length is also reduced, which in turn reduces the size and cost of the end cell magnets and shielding. As a contiuation in the series of documents covering the FPD, this report does not stand alone as a design description of FPD-III. Design details of FPD-III subsystems that do not differ significantly from those of the FPD-II configuration are not duplicated in this report.

  8. Shuttle bay telerobotics demonstration

    NASA Technical Reports Server (NTRS)

    Chun, W.; Cogeos, P.

    1987-01-01

    A demonstration of NASA's robotics capabilities should be a balanced agenda of servicing and assembly tasks combined with selected key technical experiments. The servicing tasks include refueling and module replacement. Refueling involves the mating of special fluid connectors while module replacement requires an array of robotic technologies such as special tools, the arm of a logistics tool, and the precision mating of orbital replacement units to guides. The assembly task involves the construction of a space station node and truss structure. The technological experiments will focus on a few important issues: the precision manipulation of the arms by a teleoperator, the additional use of several mono camera views in conjunction with the stereo system, the use of a general purpose end effector versus a caddy of tools, and the dynamics involved with using a robot with a stabilizer.

  9. Space Research Benefits Demonstrated

    NASA Technical Reports Server (NTRS)

    2000-01-01

    An entranced youngster watches a demonstration of the enhanced resilience of undercooled metal alloys as compared to conventional alloys. Steel bearings are dropped onto plates made of steel, titanium alloy, and zirconium liquid metal alloy, so-called because its molecular structure is amorphous and not crystalline. The bearing on the liquid metal plate bounces for a minute or more longer than on the other plates. Experiments aboard the Space Shuttle helped scientists refine their understanding of the physical properties of certain metal alloys when undercooled (i.e., kept liquid below their normal solidification temperature). This new knowledge then allowed scientists to modify a terrestrial production method so they can now make limited quantities marketed under the Liquid Metal trademark. The exhibit was a part of the NASA outreach activity at AirVenture 2000 sponsored by the Experimental Aircraft Association in Oshkosh, WI.

  10. The GLORIA demonstrator experiment

    NASA Astrophysics Data System (ADS)

    Majcher, A.; Ćwiek, A.; Ćwiok, M.; Mankiewicz, L.; Zaremba, M.; Żarnecki, A. F.

    2013-10-01

    GLORIA stands for "GLObal Robotic-telescopes Intelligent Array" and it is the first free and open-access network of robotic telescopes on the world. Based on a Web 2.0 environment amateur and professional users can do research in astronomy by observing with robotic telescopes, and/or analyzing data acquired with GLORIA, or from other free access databases. GLORIA project develops free standards, protocols and tools for controlling Robotic Telescopes and related instrumentation, for scheduling observations in the telescope network, and for conducting so-called off-line experiments based on the analysis of astronomical data. This contribution summarizes the implementation and results from the first research level off-line demonstrator experiment implemented in GLORIA, which was base on the data collected with the "Pi of the Sky" telescope in Chile.

  11. ARJIS satellite demonstration project

    NASA Astrophysics Data System (ADS)

    Severance, Steve; Williams, Carl

    2005-06-01

    In 2003, the California Space Authority (CSA) was provided funding by the U. S. Congress through the Defense Appropriations Act to develop a project that would demonstrate the U.S. space enterprise capability that would contribute to the effectiveness of those engaged in Homeland Security. The project was given broad latitude in selecting the area of Homeland Security to be addressed and the nature of the space technology to be applied. CSA became aware of a nascent law enforcement data-sharing project in the San Diego region known as the Automated Regional Justice Information System (ARJIS). First developed by the police departments in San Diego, ARJIS is an innovative system that shares criminal justice information among 50 federal, state, and local agencies. ARJIS was completing a pilot project that enabled officers to receive information on handheld computers, which was transmitted wirelessly through cellular networks. The accessed information came from several databases that collectively contained the entire region's crime and arrest reports, traffic citations, and incidents, as well as state and county wants and warrants. The fundamental limitations that plague all cellular-based devices caught CSA's attention and resulted in a cooperative effort to harden the communications link between the patrol officer and critical data. The principal goal of the SATCOM development task was to create a proof-of-concept application that would use SATCOM links to augment the current ARJIS handheld wireless (cellular) capability. The successful technical demonstration and the positive support for satellite communications from the law enforcement community showed that this project filled a need-both for improved information sharing and for highly reliable communications systems.

  12. Suppress carrier recombination by introducing defects. The case of Si solar cell

    SciTech Connect

    Liu, Yuanyue; Stradins, Paul; Deng, Huixiong; Luo, Junwei; Wei, Su -Huai

    2016-01-11

    Deep level defects are usually harmful to solar cells. Here we show that incorporation of selected deep level defects in the carrier-collecting region, however, can be utilized to improve the efficiency of optoelectronic devices. The designed defects can help the transport of the majority carriers by creating defect levels that is resonant with the band edge state, and/or reduce the concentration of minority carriers through Coulomb repulsion, thus suppressing the recombination at the carrier-collecting region. The selection process is demonstrated by using Si solar cell as an example. In conclusion, our work enriches the understanding and utilization of the semiconductor defects.

  13. Tidd PFBC demonstration project

    SciTech Connect

    Marrocco, M.

    1997-12-31

    The Tidd project was one of the first joint government-industry ventures to be approved by the US Department of Energy (DOE) in its Clean Coal Technology Program. In March 1987, DOE signed an agreement with the Ohio Power Company, a subsidiary of American Electric Power, to refurbish the then-idle Tidd plant on the banks of the Ohio River with advanced pressurized fluidized bed technology. Testing ended after 49 months of operation, 100 individual tests, and the generation of more than 500,000 megawatt-hours of electricity. The demonstration plant has met its objectives. The project showed that more than 95 percent of sulfur dioxide pollutants could be removed inside the advanced boiler using the advanced combustion technology, giving future power plants an attractive alternative to expensive, add-on scrubber technology. In addition to its sulfur removal effectiveness, the plant`s sustained periods of steady-state operation boosted its availability significantly above design projections, heightening confidence that pressurized fluidized bed technology will be a reliable, baseload technology for future power plants. The technology also controlled the release of nitrogen oxides to levels well below the allowable limits set by federal air quality standards. It also produced a dry waste product that is much easier to handle than wastes from conventional power plants and will likely have commercial value when produced by future power plants.

  14. Orbital construction demonstration study

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A conceptual design and program plan for an Orbital Construction Demonstration Article (OCDA) was developed that can be used for evaluating and establishing practical large structural assembly operations. A flight plan for initial placement and continued utility is presented as a basic for an entirely new shuttle payload line-item having great future potential benefit for space applications. The OCDA is a three-axis stabilized platform in low-earth orbit with many structural nodals for mounting large construction and fabrication equipments. This equipment would be used to explore methods for constructing the large structures for future missions. The OCDA would be supported at regular intervals by the shuttle. Construction experiments and consumables resupply are performed during shuttle visit periods. A 250 kw solar array provides sufficient power to support the shuttle while attached to the OCDA and to run construction experiments at the same time. Wide band communications with a Telemetry and Data Relay Satellite compatible high gain antenna can be used between shuttle revisits to perform remote controlled, TV assisted construction experiments.

  15. NASA Bioreactor Demonstration System

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Leland W. K. Chung (left), Director, Molecular Urology Therapeutics Program at the Winship Cancer Institute at Emory University, is principal investigator for the NASA bioreactor demonstration system (BDS-05). With him is Dr. Jun Shu, an assistant professor of Orthopedics Surgery from Kuming Medical University China. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  16. Soil bioventing demonstration project

    SciTech Connect

    Cho, J.S.; Kampbell, D.H.; Wilson, J.T.; DiGiulio, D.C.

    1990-01-01

    A pilot scale demonstration project of a soil bioventing system, which utilizes the biodegradation in soil and physical removal of VOC by induced air flow, is in operation at the U.S. Coast Guard Aviation Field in Traverse City, Michigan. The system is being tested to determine its suitability for remediation of the vadose zone in conjunction with aquifer remediation at a site contaminated by an aviation gas spill. Several microcosm studies with soil obtained from the vertical profile of the contaminated site showed rapid microbial decompositions of hydrocarbon fumes with NPK nutrient and moisture addition. Basic removal kinetics data were obtained from these experiments. Field pneumatic pump tests for soil-air characterization have been conducted. The soil-air permeability and pressure distributions under the air injection/withdrawal systems were obtained. On the basis of information from the laboratory and field tests, a conceptual design at a field scale was made. The system will be implemented on the selected study site and the operation will start in fall, 1990. Additional soil core samplings and continuous monitoring of operation are planned.

  17. Plug cluster module demonstration

    NASA Technical Reports Server (NTRS)

    Rousar, D. C.

    1978-01-01

    The low pressure, film cooled rocket engine design concept developed during two previous ALRC programs was re-evaluated for application as a module for a plug cluster engine capable of performing space shuttle OTV missions. The nominal engine mixture ratio was 5.5 and the engine life requirements were 1200 thermal cycles and 10 hours total operating life. The program consisted of pretest analysis; engine tests, performed using residual components; and posttest analysis. The pretest analysis indicated that operation of the operation of the film cooled engine at O/F = 5.5 was feasible. During the engine tests, steady state wall temperature and performance measurement were obtained over a range of film cooling flow rates, and the durability of the engine was demonstrated by firing the test engine 1220 times at a nominal performance ranging from 430 - 432 seconds. The performance of the test engine was limited by film coolant sleeve damage which had occurred during previous testing. The post-test analyses indicated that the nominal performance level can be increased to 436 seconds.

  18. Development of a Defence Distributed Computing Environment (DCE) Database Demonstrator,

    DTIC Science & Technology

    1995-11-01

    This report discusses the development of a Defence Distributed Computing Environment (DCE) database demonstrator program. The Demonstrator program...showcases the interoperability, portability, survivability and security features of Open Software Foundation’s Distributed Computing Environment.

  19. Teaching Chemistry through Observation--The Exploding Can Demonstration.

    ERIC Educational Resources Information Center

    Golestaneh, Kamran

    1998-01-01

    Describes procedures for a demonstration that features an exploding can. This demonstration prompts students to critically analyze the release of energy in an exothermic reaction, the work done in such a reaction, and the enthalpy. (DDR)

  20. Biomaterials in periodontal osseous defects

    PubMed Central

    Lal, Nand; Dixit, Jaya

    2012-01-01

    Introduction Osseous defects in periodontal diseases require osseous grafts and guided tissue regeneration (GTR) using barrier membranes. The present study was undertaken with the objectives to clinically evaluate the osteogenic potential of hydroxyapatite (HA), cissus quadrangularis (CQ), and oxidized cellulose membrane (OCM) and compare with normal bone healing. Materials and Methods Twenty subjects with periodontitis in the age group ranging from 20 years to 40 years were selected from our outpatient department on the basis of presence of deep periodontal pockets, clinical probing depth ≥5 mm, vertical osseous defects obvious on radiograph and two- or three-walled involvement seen on surgical exposure. Infrabony defects were randomly divided into four groups on the basis of treatment to be executed, such that each group comprised 5 defects. Group I was control, II received HA, III received CQ and IV received OCM. Probing depth and attachment level were measured at regular months after surgery. Defects were re-exposed using crevicular incisions at 6 months. Results There was gradual reduction in the mean probing pocket depth in all groups, but highly significant in the site treated with HA. Gain in attachment level was higher in sites treated with HA, 3.2 mm at 6 months. Conclusion Hydroxyapatite and OCM showed good reduction in pocket depth, attachment level gain and osseous defect fill. Further study should be conducted by using a combination of HA and OCM in periodontal osseous defects with growth factors and stem cells. PMID:25756030

  1. The spatial evaluation of neighborhood clusters of birth defects

    SciTech Connect

    Frisch, J.D.

    1990-04-16

    Spatial statistics have recently been applied in epidemiology to evaluate clusters of cancer and birth defects. Their use requires a comparison population, drawn from the population at risk for disease, that may not always be readily available. In this dissertation the plausibility of using data on all birth defects, available from birth defects registries, as a surrogate for the spatial distribution of all live births in the analysis of clusters is assessed. Three spatial statistics that have been applied in epidemiologic investigations of clusters, nearest neighbor distance, average interpoint distance, and average distance to a fixed point, were evaluated by computer simulation for their properties in a unit square, and in a zip code region. Comparison of spatial distributions of live births and birth defects was performed by drawing samples of live births and birth defects from Santa Clara County, determining the street address at birth, geocoding this address and evaluating the resultant maps using various statistical techniques. The proposed method was then demonstrated on a previously confirmed cluster of oral cleft cases. All live births for the neighborhood were geocoded, as were all birth defects. Evaluation of this cluster using the nearest neighbor and average interpoint distance statistics was performed using randomization techniques with both the live births population and the birth defect population as comparison groups. 113 refs., 36 figs., 16 tabs.

  2. Birth defects in the Seveso area after TCDD contamination

    SciTech Connect

    Mastroiacovo, P.; Spagnolo, A.; Marni, E.; Meazza, L.; Bertollini, R.; Segni, G.

    1988-03-18

    A study on the frequency of birth defects was conducted in the area around Seveso, Italy, which was contaminated by 2,3,7,8-tetrachlorodibenzo-p-dioxin in July 1976; this has been the largest population ever exposed to dioxin. From Jan 1, 1977, to Dec 31, 1982, a total of 15,291 births (still and live) were examined, and malformations were reported to an ad hoc birth defects registry. In the most highly contaminated area, 26 births were observed. None of these infants had any major structural defect. Two infants had mild defects. The frequencies of major defects detected in the areas of low or very low contamination were 29.9/1000 and 22.1/1000, respectively. A frequency of 27.7/1000 was registered in the control area. Relative risks were calculated for specific categories of birth defects and for grouped malformations. Although the data collected failed to demonstrate any increased risk of birth defects associated with 2,3,7,8-tetrachlorodibenzo-p-dioxin, the number of exposed pregnancies was not big enough to show a low and specific teratogenic risk increase.

  3. Demonstrating Group Process Using "12 Angry Men"

    ERIC Educational Resources Information Center

    Armstrong, Stephen A.; Berg, Robert C.

    2005-01-01

    The feature film "12 Angry Men" focuses on an organizational task group that demonstrates the dynamics of a working group. The film is discussed as an effective tool for illuminating group process. The authors describe their experiences using the movie as a teaching tool and provide examples of how it can be used to depict critical incidents, the…

  4. Technology Tips: Building Interactive Demonstrations with Sage

    ERIC Educational Resources Information Center

    Murray, Maura

    2013-01-01

    Sage is an open-source software package that can be used in many different areas of mathematics, ranging from algebra to calculus and beyond. One of the most exciting pedagogical features of Sage (http://www.sagemath.org) is its ability to create interacts--interactive examples that can be used in a classroom demonstration or by students in a…

  5. Demonstration of Berry Phase in Optical Spectroscopy

    NASA Technical Reports Server (NTRS)

    Xia, Hui-Rong; Zhang, Yong; Jiang, Hong-Ji; Ding, Liang-En

    1996-01-01

    In this paper we demonstrate that the observed phase shift of the RF signal and its intensity dependence under extreme low pump and probe laser field conditions are dominated by Berry phase effect in optical spectroscopy with good adiabatic approximation, which provides all features' agreements between the theoretical and the experimental results.

  6. Kinesthetic Transverse Wave Demonstration

    NASA Astrophysics Data System (ADS)

    Pantidos, Panagiotis; Patapis, Stamatis

    2005-09-01

    This is a variation on the String and Sticky Tape demonstration "The Wave Game," suggested by Ron Edge. A group of students stand side by side, each one holding a card chest high with both hands. The teacher cues the first student to begin raising and lowering his card. When he starts lowering his card, the next student begins to raise his. As succeeding students move their cards up and down, a wave such as that shown in the figure is produced. To facilitate the process, students' motions were synchronized with the ticks of a metronome (without such synchronization it was nearly impossible to generate a satisfactory wave). Our waves typically had a frequency of about 1 Hz and a wavelength of around 3 m. We videotaped the activity so that the students could analyze the motions. The (17-year-old) students had not received any prior instruction regarding wave motion and did not know beforehand the nature of the exercise they were about to carry out. During the activity they were asked what a transverse wave is. Most of them quickly realized, without teacher input, that while the wave propagated horizontally, the only motion of the transmitting medium (them) was vertical. They located the equilibrium points of the oscillations, the crests and troughs of the waves, and identified the wavelength. The teacher defined for them the period of the oscillations of the motion of a card to be the total time for one cycle. The students measured this time and then several asserted that it was the same as the wave period. Knowing the length of the waves and the number of waves per second, the next step can easily be to find the wave speed.

  7. Raman Spectroscopy as an Accurate Probe of Defects in Graphene

    NASA Astrophysics Data System (ADS)

    Rodriguez-Nieva, Joaquin; Barros, Eduardo; Saito, Riichiro; Dresselhaus, Mildred

    2014-03-01

    Raman Spectroscopy has proved to be an invaluable non-destructive technique that allows us to obtain intrinsic information about graphene. Furthermore, defect-induced Raman features, namely the D and D' bands, have previously been used to assess the purity of graphitic samples. However, quantitative studies of the signatures of the different types of defects on the Raman spectra is still an open problem. Experimental results already suggest that the Raman intensity ratio ID /ID' may allow us to identify the nature of the defects. We study from a theoretical point of view the power and limitations of Raman spectroscopy in the study of defects in graphene. We derive an analytic model that describes the Double Resonance Raman process of disordered graphene samples, and which explicitly shows the role played by both the defect-dependent parameters as well as the experimentally-controlled variables. We compare our model with previous Raman experiments, and use it to guide new ways in which defects in graphene can be accurately probed with Raman spectroscopy. We acknowledge support from NSF grant DMR1004147.

  8. Care and Treatment for Congenital Heart Defects

    MedlinePlus

    ... Physical Activity Recommendations for Heart Health • Tools & Resources Web Booklets on Congenital Heart Defects These online publications ... to you or your child’s defect and concerns. Web Booklet: Adults With Congenital Heart Defects Web Booklet: ...

  9. Reproduction and Survival After Cardiac Defect Repair

    ClinicalTrials.gov

    2016-02-17

    Cardiovascular Diseases; Heart Diseases; Defect, Congenital Heart; Aortic Valve Stenosis; Transposition of Great Vessels; Ductus Arteriosus, Patent; Heart Septal Defects, Atrial; Heart Septal Defects, Ventricular; Down Syndrome; Tetralogy of Fallot; Pulmonic Stenosis; Coarctation of Aorta

  10. Systems Biology and Birth Defects Prevention: Blockade of the Glucocorticoid Receptor Prevents Arsenic-Induced Birth Defects

    PubMed Central

    Ahir, Bhavesh K.; Sanders, Alison P.; Rager, Julia E.

    2013-01-01

    Background: The biological mechanisms by which environmental metals are associated with birth defects are largely unknown. Systems biology–based approaches may help to identify key pathways that mediate metal-induced birth defects as well as potential targets for prevention. Objectives: First, we applied a novel computational approach to identify a prioritized biological pathway that associates metals with birth defects. Second, in a laboratory setting, we sought to determine whether inhibition of the identified pathway prevents developmental defects. Methods: Seven environmental metals were selected for inclusion in the computational analysis: arsenic, cadmium, chromium, lead, mercury, nickel, and selenium. We used an in silico strategy to predict genes and pathways associated with both metal exposure and developmental defects. The most significant pathway was identified and tested using an in ovo whole chick embryo culture assay. We further evaluated the role of the pathway as a mediator of metal-induced toxicity using the in vitro midbrain micromass culture assay. Results: The glucocorticoid receptor pathway was computationally predicted to be a key mediator of multiple metal-induced birth defects. In the chick embryo model, structural malformations induced by inorganic arsenic (iAs) were prevented when signaling of the glucocorticoid receptor pathway was inhibited. Further, glucocorticoid receptor inhibition demonstrated partial to complete protection from both iAs- and cadmium-induced neurodevelopmental toxicity in vitro. Conclusions: Our findings highlight a novel approach to computationally identify a targeted biological pathway for examining birth defects prevention. PMID:23458687

  11. Transforming graphene nanoribbons into nanotubes by use of point defects.

    PubMed

    Sgouros, A; Sigalas, M M; Papagelis, K; Kalosakas, G

    2014-03-26

    Using molecular dynamics simulations with semi-empirical potentials, we demonstrate a method to fabricate carbon nanotubes (CNTs) from graphene nanoribbons (GNRs), by periodically inserting appropriate structural defects into the GNR crystal structure. We have found that various defect types initiate the bending of GNRs and eventually lead to the formation of CNTs. All kinds of carbon nanotubes (armchair, zigzag, chiral) can be produced with this method. The structural characteristics of the resulting CNTs, and the dependence on the different type and distribution of the defects, were examined. The smallest (largest) CNT obtained had a diameter of ∼ 5 Å (∼ 39 Å). Proper manipulation of ribbon edges controls the chirality of the CNTs formed. Finally, the effect of randomly distributed defects on the ability of GNRs to transform into CNTs is considered.

  12. Quantification of osteoarticular joint defects through bone segmentation and modeling.

    PubMed

    Yang, Jian; Fu, Tianyu; Ai, Danni; Xing, Huijun; Li, Qin; Wang, Yongtian

    2014-01-01

    Shoulder instability is a major threat to people's daily life. Many patients suffer from shoulder instability such as the loss of the glenoid and humeral head. In clinical practice, an accurate 3D structure estimation of damaged joints is necessary to diagnose and treat bone defects. This study quantifies osteoarticular defects through the modeling and visualization of osteoarticular structures. An improved algorithm to extract the 3D structure of the bones is proposed. The bone contour is then automatically extracted using prior shape and gray scale intensity distribution of joint CT images. Joint structures with mirror symmetry are matched using the Iterative Closest Point registration algorithm. Osteoarticular defects can be quantified on the basis of the symmetric information of the bones. Experimental results demonstrate that the proposed method can effectively segment the joint structures from the CT image. In addition, the proposed mirror symmetrical method can effectively estimate osteoarticular defects.

  13. Sparse Reconstruction for Micro Defect Detection in Acoustic Micro Imaging

    PubMed Central

    Zhang, Yichun; Shi, Tielin; Su, Lei; Wang, Xiao; Hong, Yuan; Chen, Kepeng; Liao, Guanglan

    2016-01-01

    Acoustic micro imaging has been proven to be sufficiently sensitive for micro defect detection. In this study, we propose a sparse reconstruction method for acoustic micro imaging. A finite element model with a micro defect is developed to emulate the physical scanning. Then we obtain the point spread function, a blur kernel for sparse reconstruction. We reconstruct deblurred images from the oversampled C-scan images based on l1-norm regularization, which can enhance the signal-to-noise ratio and improve the accuracy of micro defect detection. The method is further verified by experimental data. The results demonstrate that the sparse reconstruction is effective for micro defect detection in acoustic micro imaging. PMID:27783040

  14. Silylene Defect at the Dihydrogen Terminated (100) Si Surface

    NASA Astrophysics Data System (ADS)

    Belanzoni, P.; Giorgi, G.; Sgamellotti, A.; Cerofolini, G. F.

    2009-09-01

    Density functional calculations for both periodic slabs and different size cluster models of the hydrogen-terminated (100) surface of silicon are used to study a new configuration, formed by a silylene center interacting with vicinal silicon dihydrides through nonconventional hydrogen bonds. A comparison between slab-model and cluster-model approaches to modeling surface silylene defect formation processes is presented. The cluster models are used to analyze the structure and bonding of the silylene with a Lewis acid and base, showing the Zwitterionic nature of the defect. The silylene is also demonstrated to behave as a strong Brønsted acid. The stabilization of the silylene defect via interaction with species unavoidably present in the HFaq-etching solution is investigated. Finally, the negative chemical shift observed by X-ray photoelectron spectroscopy in the HFaq-etched (100) Si surface is attributed to the occurrence of silylene defect.

  15. Sparse Reconstruction for Micro Defect Detection in Acoustic Micro Imaging.

    PubMed

    Zhang, Yichun; Shi, Tielin; Su, Lei; Wang, Xiao; Hong, Yuan; Chen, Kepeng; Liao, Guanglan

    2016-10-24

    Acoustic micro imaging has been proven to be sufficiently sensitive for micro defect detection. In this study, we propose a sparse reconstruction method for acoustic micro imaging. A finite element model with a micro defect is developed to emulate the physical scanning. Then we obtain the point spread function, a blur kernel for sparse reconstruction. We reconstruct deblurred images from the oversampled C-scan images based on l₁-norm regularization, which can enhance the signal-to-noise ratio and improve the accuracy of micro defect detection. The method is further verified by experimental data. The results demonstrate that the sparse reconstruction is effective for micro defect detection in acoustic micro imaging.

  16. Severe mitral regurgitation due to an extraordinary heart defect.

    PubMed

    García-Ropero, Álvaro; Cortés García, Marcelino; Aldamiz Echevarría, Gonzalo; Farré Muncharaz, Jerónimo

    2016-09-01

    A previously non-described cause of mitral regurgitation is presented. An asymptomatic 50-year old male who was casually diagnosed of mitral valve Barlow's disease underwent cardiac surgery due to severe mitral regurgitation. In the operating theatre, a longitudinal fissure of 1.5-2.0 cm length, along the posterior mitral leaflet, was found responsible for the insufficiency. This defect had features of a potential congenital origin and it was successfully repaired with direct suture. Whether it is an atypical mitral cleft, a variation of Barlow's morphology spectrum or a new congenital heart defect remains unclear.

  17. Reconstruction of skull base defects in sphenoid wing dysplasia associated with neurofibromatosis I with titanium mesh.

    PubMed

    Lotfy, Mohamed; Xu, Risheng; McGirt, Matthew; Sakr, Sameh; Ayoub, Basim; Bydon, Ali

    2010-12-01

    Sphenoid wing dysplasia occurs in 3-7% of patients with neurofibromatosis type 1 (NF1). The typical radiological features are partial or complete absence of the greater wing of the sphenoid. This condition is slowly progressive and may result in temporal lobe herniation into the orbital cavity, producing pulsating exophthalmos and gross facial deformity. Thus, reconstruction of the orbit is important for both cosmetic and functional reasons. Traditional surgical treatment of sphenoid dysplasia involves split bone grafting and repair of the anterior skull base defect. However, several reports have demonstrated complications of graft resorption and recurrence of proptosis and pulsating exopthalmos. In this case series, we present two patients suffering from pulsating exophthalmos due to sphenoid dysplasia. Radiological and MRI studies demonstrated orbital enlargement and complete absence of the greater wing of the sphenoid. Surgical management of these patients involved dural defect repair, and the use of titanium mesh in conjunction with bone graft to act as a barrier between the orbit and the middle cranial fossa. The mesh was fixed by fine screws. Proptosis improved markedly post-operatively and resolved within a few weeks. Ocular pulsation subsided and remained quiescent with at least 1-year follow-up.

  18. Low quantum defect laser performance

    NASA Astrophysics Data System (ADS)

    Bowman, Steven R.

    2017-01-01

    Low quantum defect lasers are possible using near-resonant optical pumping. This paper examines the laser material performance as the quantum defect of the laser is reduced. A steady-state model is developed, which incorporates the relevant physical processes in these materials and predicts extraction efficiency and waste heat generation. As the laser quantum defect is reduced below a few percent, the impact of fluorescence cooling must be included in the analysis. The special case of a net zero quantum defect laser is examined in detail. This condition, referred to as the radiation balance laser (RBL), is shown to provide two orders of magnitude lower heat generation at the cost of roughly 10% loss in extraction efficiency. Numerical examples are presented with the host materials Yb:YAG and Yb:Silica. The general conditions, which yield optimal laser efficiency, are derived and explored.

  19. Congenital Heart Defects (For Parents)

    MedlinePlus

    ... heart, lungs, and blood vessels make up the circulatory system . The heart is the central pump of this ... Heart Defects Getting an EKG (Video) Your Heart & Circulatory System Heart Murmurs Mitral Valve Prolapse Movie: Heart & Circulatory ...

  20. Sequential detection of web defects

    DOEpatents

    Eichel, Paul H.; Sleefe, Gerard E.; Stalker, K. Terry; Yee, Amy A.

    2001-01-01

    A system for detecting defects on a moving web having a sequential series of identical frames uses an imaging device to form a real-time camera image of a frame and a comparitor to comparing elements of the camera image with corresponding elements of an image of an exemplar frame. The comparitor provides an acceptable indication if the pair of elements are determined to be statistically identical; and a defective indication if the pair of elements are determined to be statistically not identical. If the pair of elements is neither acceptable nor defective, the comparitor recursively compares the element of said exemplar frame with corresponding elements of other frames on said web until one of the acceptable or defective indications occur.

  1. Atrial Septal Defect (For Teens)

    MedlinePlus

    ... septal defect (pronounced: AY-tree-ul SEP-tul DEE-fekt), or ASD for short, is sometimes referred ... can be treated with cardiac catheterization (pronounced: CAR-dee-ack cath-uh-turr-ih-ZAY-shun), in ...

  2. Atrial Septal Defect (For Kids)

    MedlinePlus

    ... wall called the septum that normally separates the blue and red blood. In a person with an atrial septal defect, there's an opening in that wall. This hole in the wall lets oxygen-rich blood from ...

  3. Disorder and defects are not intrinsic to boron carbide.

    PubMed

    Mondal, Swastik; Bykova, Elena; Dey, Somnath; Ali, Sk Imran; Dubrovinskaia, Natalia; Dubrovinsky, Leonid; Parakhonskiy, Gleb; van Smaalen, Sander

    2016-01-18

    A unique combination of useful properties in boron-carbide, such as extreme hardness, excellent fracture toughness, a low density, a high melting point, thermoelectricity, semi-conducting behavior, catalytic activity and a remarkably good chemical stability, makes it an ideal material for a wide range of technological applications. Explaining these properties in terms of chemical bonding has remained a major challenge in boron chemistry. Here we report the synthesis of fully ordered, stoichiometric boron-carbide B13C2 by high-pressure-high-temperature techniques. Our experimental electron-density study using high-resolution single-crystal synchrotron X-ray diffraction data conclusively demonstrates that disorder and defects are not intrinsic to boron carbide, contrary to what was hitherto supposed. A detailed analysis of the electron density distribution reveals charge transfer between structural units in B13C2 and a new type of electron-deficient bond with formally unpaired electrons on the C-B-C group in B13C2. Unprecedented bonding features contribute to the fundamental chemistry and materials science of boron compounds that is of great interest for understanding structure-property relationships and development of novel functional materials.

  4. Disorder and defects are not intrinsic to boron carbide

    PubMed Central

    Mondal, Swastik; Bykova, Elena; Dey, Somnath; Ali, Sk Imran; Dubrovinskaia, Natalia; Dubrovinsky, Leonid; Parakhonskiy, Gleb; van Smaalen, Sander

    2016-01-01

    A unique combination of useful properties in boron-carbide, such as extreme hardness, excellent fracture toughness, a low density, a high melting point, thermoelectricity, semi-conducting behavior, catalytic activity and a remarkably good chemical stability, makes it an ideal material for a wide range of technological applications. Explaining these properties in terms of chemical bonding has remained a major challenge in boron chemistry. Here we report the synthesis of fully ordered, stoichiometric boron-carbide B13C2 by high-pressure–high-temperature techniques. Our experimental electron-density study using high-resolution single-crystal synchrotron X-ray diffraction data conclusively demonstrates that disorder and defects are not intrinsic to boron carbide, contrary to what was hitherto supposed. A detailed analysis of the electron density distribution reveals charge transfer between structural units in B13C2 and a new type of electron-deficient bond with formally unpaired electrons on the C–B–C group in B13C2. Unprecedented bonding features contribute to the fundamental chemistry and materials science of boron compounds that is of great interest for understanding structure-property relationships and development of novel functional materials. PMID:26777140

  5. Evaluating Printability of Buried Native EUV Mask Phase Defects through a Modeling and Simulation Approach

    SciTech Connect

    Upadhyaya, Mihir; Jindal, Vibhu; Basavalingappa, Adarsh; Herbol, Henry; Harris-Jones, Jenah; Jang, Il-Yong; Goldberg, Kenneth A.; Mochi, Iacopo; Marokkey, Sajan; Demmerle, Wolfgang; Pistor, Thomas V.; Denbeaux, Gregory

    2015-03-16

    The availability of defect-free masks is considered to be a critical issue for enabling extreme ultraviolet lithography (EUVL) as the next generation technology. Since completely defect-free masks will be hard to achieve, it is essential to have a good understanding of the printability of the native EUV mask defects. In this work, we performed a systematic study of native mask defects to understand the defect printability caused by them. The multilayer growth over native substrate mask blank defects was correlated to the multilayer growth over regular-shaped defects having similar profiles in terms of their width and height. To model the multilayer growth over the defects, a novel level-set multilayer growth model was used that took into account the tool deposition conditions of the Veeco Nexus ion beam deposition tool. The same tool was used for performing the actual deposition of the multilayer stack over the characterized native defects, thus ensuring a fair comparison between the actual multilayer growth over native defects, and modeled multilayer growth over regular-shaped defects. Further, the printability of the characterized native defects was studied with the SEMATECH-Berkeley Actinic Inspection Tool (AIT), an EUV mask-imaging microscope at Lawrence Berkeley National Laboratory (LBNL). Printability of the modeled regular-shaped defects, which were propagated up the multilayer stack using level-set growth model was studied using defect printability simulations implementing the waveguide algorithm. Good comparison was observed between AIT and the simulation results, thus demonstrating that multilayer growth over a defect is primarily a function of a defect’s width and height, irrespective of its shape. This would allow us to predict printability of the arbitrarily-shaped native EUV mask defects in a systematic and robust manner.

  6. Stable line defects in silicene

    NASA Astrophysics Data System (ADS)

    Ghosh, Dibyajyoti; Parida, Prakash; Pati, Swapan K.

    2015-11-01

    Line defects in two-dimensional (2D) materials greatly modulate various properties of their pristine form. Using ab initio molecular dynamics (AIMD) simulations, we investigate the structural reconstructions of different kinds of grain boundaries in the silicene sheets. It is evident that depending upon the presence of silicon adatoms and edge shape of grain boundaries (i.e., armchair or zigzag), stable extended line defects (ELDs) can be introduced in a controlled way. Further studies show the stability of these line-defects in silicene, grown on Ag(111) surface at room-temperature. Importantly, unlike most of the 2D sheet materials such as graphene and hexagonal boron nitride, 5-5-8 line defects modify the nonmagnetic semimetallic pristine silicene sheet to spin-polarized metal. As ferromagnetically ordered magnetic moments remain strongly localized at the line defect, a one-dimensional spin channel gets created in silicene. Interestingly, these spin channels are quite stable because, unlike the edge of nanoribbons, structural reconstruction or contamination cannot destroy the ordering of magnetic moments here. Zigzag silicene nanoribbons with a 5-5-8 line defect also exhibit various interesting electronic and magnetic properties depending upon their width as well as the nature of the magnetic coupling between edge and defect spin states. Upon incorporation of other ELDs, such as 4-4-4 and 4-8 defects, 2D sheets and nanoribbons of silicene show a nonmagnetic metallic or semiconducting ground state. Highlighting the controlled formation of ELDs and consequent emergence of technologically important properties in silicene, we propose new routes to realize silicene-based nanoelectronic and spintronic devices.

  7. Intrauterine infections and birth defects.

    PubMed

    Zheng, Xiao-Ying; Zhang, Ting; Wang, Yi-Fei; Xu, Chen; Chen, Gong; Xin, Ruo-Lei; Chen, Jia-Peng; Hu, Xu-Mei; Yang, Qing; Song, Xin-Ming; Pang, Li-Hua; Ji, Ying; Sun, Hong-Mei; Zhang, Lei; Liu, Ju-Fen; Guo, Yan-Ling; Zhang, Yan

    2004-12-01

    Intrauterine infection is an important cause of some birth defects worldwide. The most common pathogens include rubella virus, cytomegaloviurs, ureaplasma urealyticum, toxoplasma, etc. General information about these pathogens in epidemiology, consequence of birth defects, and the possible mechanisms in the progress of birth defects, and the interventions to prevent or treat these pathogens' infections are described. The infections caused by rubella virus, cytomegaloviurs, ureaplasma urealyticum, toxoplasma, etc. are common, yet they are proved to be fatal during the pregnant period, especially during the first trimester. These infections may cause sterility, abortion, stillbirth, low birth weight, and affect multiple organs that may induce loss of hearing and vision, even fetal deformity and the long-term effects. These pathogens' infections may influence the microenvironment of placenta, including levels of enzymes and cytokines, and affect chondriosome that may induce the progress of birth defect. Early diagnosis of infections during pregnancy should be strengthened. There are still many things to be settled, such as the molecular mechanisms of birth defects, the effective vaccines to certain pathogens. Birth defect researches in terms of etiology and the development of applicable and sensitive pathogen detection technology and methods are imperative.

  8. Topological defects from the multiverse

    SciTech Connect

    Zhang, Jun; Blanco-Pillado, Jose J.; Garriga, Jaume; Vilenkin, Alexander

    2015-05-28

    Many theories of the early universe predict the existence of a multiverse where bubbles continuously nucleate giving rise to observers in their interior. In this paper, we point out that topological defects of several dimensionalities will also be produced in de Sitter like regions of the multiverse. In particular, defects could be spontaneously nucleated in our parent vacuum. We study the evolution of these defects as they collide with and propagate inside of our bubble. We estimate the present distribution of defects in the observable part of the universe. The expected number of such nearby defects turns out to be quite small, even for the highest nucleation rate. We also study collisions of strings and domain walls with our bubble in our past light cone. We obtain simulated full-sky maps of the loci of such collisions, and find their angular size distribution. Similarly to what happens in the case of bubble collisions, the prospect of detecting any collisions of our bubble with ambient defects is greatly enhanced in the case where the cosmological constant of our parent vacuum is much higher than the vacuum energy density during inflation in our bubble.

  9. Topological defects from the multiverse

    SciTech Connect

    Zhang, Jun; Vilenkin, Alexander; Blanco-Pillado, Jose J.

    2015-05-01

    Many theories of the early universe predict the existence of a multiverse where bubbles continuously nucleate giving rise to observers in their interior. In this paper, we point out that topological defects of several dimensionalities will also be produced in de Sitter like regions of the multiverse. In particular, defects could be spontaneously nucleated in our parent vacuum. We study the evolution of these defects as they collide with and propagate inside of our bubble. We estimate the present distribution of defects in the observable part of the universe. The expected number of such nearby defects turns out to be quite small, even for the highest nucleation rate. We also study collisions of strings and domain walls with our bubble in our past light cone. We obtain simulated full-sky maps of the loci of such collisions, and find their angular size distribution. Similarly to what happens in the case of bubble collisions, the prospect of detecting any collisions of our bubble with ambient defects is greatly enhanced in the case where the cosmological constant of our parent vacuum is much higher than the vacuum energy density during inflation in our bubble.

  10. Observation of 3D defect mediated dust acoustic wave turbulence with fluctuating defects and amplitude hole filaments

    SciTech Connect

    Chang, Mei-Chu; Tsai, Ya-Yi; I, Lin

    2013-08-15

    We experimentally demonstrate the direct observation of defect mediated wave turbulence with fluctuating defects and low amplitude hole filaments, from a 3D self-excited plane dust acoustic wave in a dusty plasma by reducing dissipation. The waveform undulation is found to be the origin for the amplitude and the phase modulations of the local dust density oscillation, the broadening of the sharp peaks in the frequency spectrum, and the fluctuating defects. The corrugated wave crest surface also causes the observed high and low density patches in the transverse (xy) plane. Low oscillation amplitude spots (holes) share the same positions with the defects. Their trajectories in the xyt space appear in the form of chaotic filaments without long term predictability, through uncertain pair generation, propagation, and pair annihilation.

  11. Patterned fabric defect detection via convolutional matching pursuit dual-dictionary

    NASA Astrophysics Data System (ADS)

    Jing, Junfeng; Fan, Xiaoting; Li, Pengfei

    2016-05-01

    Automatic patterned fabric defect detection is a promising technique for textile manufacturing due to its low cost and high efficiency. The applicability of most existing algorithms, however, is limited by their intensive computation. To overcome or alleviate the problem, this paper presents a convolutional matching pursuit (CMP) dual-dictionary algorithm for patterned fabric defect detection. A preprocessing with mean sampling is performed to eliminate the influence of background texture of fabric defects. Subsequently, a set of defect-free image blocks are selected as a sample set by sliding window. Dual-dictionary and sparse coefficiencies of the defect-free sample set are obtained via CMP and the K-singular value decomposition (K-SVD) based on a Gabor filter. Then we employ the defect-free and defective fabric image's projections onto the dual-dictionary as features for defect detection. Finally, the test results are determined by comparing the distance between the features to be measured. Experimental results reveal that the proposed algorithm is effective for patterned fabric defect detection and an acceptable average detection rate reaches by 94.2%.

  12. Apollo 14 composite casting demonstration

    NASA Technical Reports Server (NTRS)

    1971-01-01

    This program assisted in the design and implementation of the composite casting demonstration for the Apollo 14 mission. Both flight and control samples were evaluated. Some conclusions resulting from a comparison of the flight and control samples were: (1) Solidification in neither the flight nor control samples was truly directional. (2) Apparent intermittent contact of the melt with the container in the flight samples led to unusual nucleation and growth structures. (3) There was greater uniformity, on a macro scale, of both pores and structural features in the flight sample; presumably the result of the reduced gravity conditions. (4) It seems quite feasible to produce enhanced dispersions of gases and dense phases in a melt which is solidified in reduced gravity. (5) A two-stage heating/cooling cycle may help directional solidification. (6) Sample materials should be selected from materials in which the dispersant fully wets the matrix material. (7) Experiments should be conducted in two modes: (1) where the melt is in good thermal contact with the container, and (2) where the melt is in a free-float condition.

  13. Covariance based outlier detection with feature selection.

    PubMed

    Zwilling, Chris E; Wang, Michelle Y

    2016-08-01

    The present covariance based outlier detection algorithm selects from a candidate set of feature vectors that are best at identifying outliers. Features extracted from biomedical and health informatics data can be more informative in disease assessment and there are no restrictions on the nature and number of features that can be tested. But an important challenge for an algorithm operating on a set of features is for it to winnow the effective features from the ineffective ones. The powerful algorithm described in this paper leverages covariance information from the time series data to identify features with the highest sensitivity for outlier identification. Empirical results demonstrate the efficacy of the method.

  14. Suppression effects in feature-based attention

    PubMed Central

    Wang, Yixue; Miller, James; Liu, Taosheng

    2015-01-01

    Attending to a feature enhances visual processing of that feature, but it is less clear what occurs to unattended features. Single-unit recording studies in middle temporal (MT) have shown that neuronal modulation is a monotonic function of the difference between the attended and neuron's preferred direction. Such a relationship should predict a monotonic suppressive effect in psychophysical performance. However, past research on suppressive effects of feature-based attention has remained inconclusive. We investigated the suppressive effect for motion direction, orientation, and color in three experiments. We asked participants to detect a weak signal among noise and provided a partially valid feature cue to manipulate attention. We measured performance as a function of the offset between the cued and signal feature. We also included neutral trials where no feature cues were presented to provide a baseline measure of performance. Across three experiments, we consistently observed enhancement effects when the target feature and cued feature coincided and suppression effects when the target feature deviated from the cued feature. The exact profile of suppression was different across feature dimensions: Whereas the profile for direction exhibited a “rebound” effect, the profiles for orientation and color were monotonic. These results demonstrate that unattended features are suppressed during feature-based attention, but the exact suppression profile depends on the specific feature. Overall, the results are largely consistent with neurophysiological data and support the feature-similarity gain model of attention. PMID:26067533

  15. High-throughput automatic defect review for 300mm blank wafers with atomic force microscope

    NASA Astrophysics Data System (ADS)

    Zandiatashbar, Ardavan; Kim, Byong; Yoo, Young-kook; Lee, Keibock; Jo, Ahjin; Lee, Ju Suk; Cho, Sang-Joon; Park, Sang-il

    2015-03-01

    While feature size in lithography process continuously becomes smaller, defect sizes on blank wafers become more comparable to device sizes. Defects with nm-scale characteristic size could be misclassified by automated optical inspection (AOI) and require post-processing for proper classification. Atomic force microscope (AFM) is known to provide high lateral and the highest vertical resolution by mechanical probing among all techniques. However, its low throughput and tip life in addition to the laborious efforts for finding the defects have been the major limitations of this technique. In this paper we introduce automatic defect review (ADR) AFM as a post-inspection metrology tool for defect study and classification for 300 mm blank wafers and to overcome the limitations stated above. The ADR AFM provides high throughput, high resolution, and non-destructive means for obtaining 3D information for nm-scale defect review and classification.

  16. Effects of Leading Edge Defect on the Aerodynamic and Flow Characteristics of an S809 Airfoil

    PubMed Central

    Wang, Yan; Zheng, Xiaojing; Hu, Ruifeng; Wang, Ping

    2016-01-01

    nearly remain unchanged. In dynamic stall, leading edge defect imposes a greater influence on the aerodynamic characteristics of airfoil than steady conditions. By increasing in defect length, it is found that the separated area becomes more intense and moves forward along the suction surface. Conclusions Leading edge defect has significant influence on the aerodynamic and flow characteristics of the airfoil, which will reach a stable status with enough large defect size. The leading edge separation bubble, circulation in the defect cavity and intense tailing edge vortex are the main features of flow around defective airfoils. PMID:27658310

  17. Automated inspection of micro-defect recognition system for color filter

    NASA Astrophysics Data System (ADS)

    Jeffrey Kuo, Chung-Feng; Peng, Kai-Ching; Wu, Han-Cheng; Wang, Ching-Chin

    2015-07-01

    This study focused on micro-defect recognition and classification in color filters. First, six types of defects were examined, namely grain, black matrix hole (BMH), indium tin oxide (ITO) defect, missing edge and shape (MES), highlights, and particle. Orthogonal projection was applied to locate each pixel in a test image. Then, an image comparison was performed to mark similar blocks on the test image. The block that best resembled the template was chosen as the new template (or matching adaptive template). Afterwards, image subtraction was applied to subtract the pixels at the same location in each block of the test image from the matching adaptive template. The control limit law employed logic operation to separate the defect from the background region. The complete defect structure was obtained by the morphology method. Next, feature values, including defect gray value, red, green, and blue (RGB) color components, and aspect ratio were obtained as the classifier input. The experimental results showed that defect recognition could be completed as fast as 0.154 s using the proposed recognition system and software. In micro-defect classification, back-propagation neural network (BPNN) and minimum distance classifier (MDC) served as the defect classification decision theories for the five acquired feature values. To validate the proposed system, this study used 41 defects as training samples, and treated the feature values of 307 test samples as the BPNN classifier inputs. The total recognition rate was 93.7%. When an MDC was used, the total recognition rate was 96.8%, indicating that the MDC method is feasible in applying automatic optical inspection technology to classify micro-defects of color filters. The proposed system is proven to successfully improve the production yield and lower costs.

  18. Defects formation and wave emitting from defects in excitable media

    NASA Astrophysics Data System (ADS)

    Ma, Jun; Xu, Ying; Tang, Jun; Wang, Chunni

    2016-05-01

    Abnormal electrical activities in neuronal system could be associated with some neuronal diseases. Indeed, external forcing can cause breakdown even collapse in nervous system under appropriate condition. The excitable media sometimes could be described by neuronal network with different topologies. The collective behaviors of neurons can show complex spatiotemporal dynamical properties and spatial distribution for electrical activities due to self-organization even from the regulating from central nervous system. Defects in the nervous system can emit continuous waves or pulses, and pacemaker-like source is generated to perturb the normal signal propagation in nervous system. How these defects are developed? In this paper, a network of neurons is designed in two-dimensional square array with nearest-neighbor connection type; the formation mechanism of defects is investigated by detecting the wave propagation induced by external forcing. It is found that defects could be induced under external periodical forcing under the boundary, and then the wave emitted from the defects can keep balance with the waves excited from external forcing.

  19. Favorite Demonstrations: Gaseous Diffusion: A Demonstration of Graham's Law.

    ERIC Educational Resources Information Center

    Kauffman, George B.; Ebner, Ronald D.

    1985-01-01

    Describes a demonstration in which gaseous ammonia and hydrochloric acid are used to illustrate rates of diffusion (Graham's Law). Simple equipment needed for the demonstration include a long tube, rubber stoppes, and cotton. Two related demonstrations are also explained. (DH)

  20. Thyroid hormone transporter defects.

    PubMed

    Grüters, Annette

    2007-01-01

    In in vitro experiments, active transport of thyroid hormones had been repeatedly demonstrated. The membrane transporters for thyroid hormones which have been identified include the organic anion transporting polypeptide, heterodimeric amino acid transporters and the monocarboxylate transporters (MCT) which are the focus of this chapter. The gene encoding MCT8 which was identified as a specific thyroid hormone transporter is located on chromosome Xq13.2. The expression pattern of MCT8 indicates that MCT8 plays an important role in the development of the central nervous system by transporting thyroid hormone into neurons as its main target cells. Mutational analysis of the MCT8 gene revealed mutations or deletions in the MCT8 gene in unrelated male patients with severe psychomotor retardation and biochemical findings consistent with thyroid hormone resistance. Indeed, thyroid function tests in patients with MCT8 mutations demonstrated marked elevations of serum T3 (in the thyrotoxic range), a significant decrease in serum T4 or fT4 and normal to elevated TSH levels.

  1. [Myotonia and cardiac conduction defects in myotonic dystrophy and defect in ion channels].

    PubMed

    Kubota, Tomoya; Nakamori, Masayuki; Takahashi, Masanori P

    2014-03-01

    Myotonic dystrophy (DM), the most common hereditary muscle disease in adults, is caused by the unstable genomic expansion of simple sequence repeats. This disease is characterized by myotonia and various multisystemic complications, most commonly those of the cardiac, endocrine, and central nervous systems. The cardiac abnormalities, especially cardiac conduction defects, significantly contribute to morbidity and mortality in DM patients. Therefore, understanding the pathophysiology of cardiac conduction defects in DM is important. The pathomechanism of DM has been thoroughly investigated. The mutant RNA transcripts containing the expanded repeat give rise to a toxic gain-of-function by perturbing splicing factors in the nucleus, leading to the misregulation of alternative pre-mRNA splicing. In particular, several studies, including ours, have shown that myotonia is caused by alternative splicing of the CLCN1 gene coding the voltage-gated chloride channel in skeletal muscle through an "RNA-dominant mechanism". Since the aberrantly spliced isoform does not seem to form a functional channel, the feature of skeletal muscle in DM can be interpreted as a "channelopathy" caused by reduced chloride channel protein. Similarly, we recently identified a misregulation of alternative splicing in an ion channel gene which is known to be responsible for arrhythmic disease showing Mendelian inheritance. Here, we review the cardiac manifestation and RNA-dominant mechanism of DM, and discuss the possible pathophysiology of cardiac conduction defects by referring to hereditary arrhythmic diseases, such as long QT syndrome and Brugada syndrome.

  2. Application of Hilbert-Huang transform for defect recognition in pulsed eddy current testing

    NASA Astrophysics Data System (ADS)

    Liu, Baoling; Huang, Pingjie; Hou, Dibo; Chen, Xiao; Zhang, Guangxin

    2015-07-01

    Defect recognition plays an important role in the structure integrity and health monitor of in-service equipment. However, it is difficult to recognise deep-layer defect or small-size defect in conductive structure during pulsed eddy current (PEC) testing. Aiming at the issue, this article proposes a method based on Hilbert-Huang transform which consists of two modules: data processing and defect recognition. In the data processing module, the PEC response signal is decomposed into a few of intrinsic mode functions (IMFs) using ensemble empirical mode decomposition method. The IMFs whose variance contribution rates are bigger than 1% are chosen to reconstruct signal in order to remove noise. In the defect recognition module, the features based on specific frequency components of marginal spectrum (MS) of the reconstructed signals are extracted to discriminate those defects in surface and subsurface. Furthermore, the normalisation MS energy ratio is proposed to quantify defects which cannot be distinguished using peak value in time domain. Experiments show that the proposed method can achieve better de-noising effect and defect evaluation, which contributes to the recognition of those complicated defects such as deep-layered and small-sized defect.

  3. Effective actions for bosonic topological defects

    NASA Technical Reports Server (NTRS)

    Gregory, Ruth

    1990-01-01

    A gauge field theory is considered which admits p-dimensional topological defects, expanding the equations of motion in powers of the defect thickness. In this way an effective action and effective equation of motion is derived for the defect in terms of the coordinates of the p-dimensional worldsurface defined by the history of the core of the defect.

  4. Photo-induced Defects in Semiconductors

    NASA Astrophysics Data System (ADS)

    Redfield, David; Bube, Richard H.

    2006-03-01

    1. Introduction: metastable defects; 2. III-V compounds: DX2 and EL2 centers; 3. Other crystalline materials; 4. Hydrogenated amorphous silicon: properties of defects; 5. Hydrogenated amorphous silicon: photo-induced defect kinetics and processes; 6. Other amorphous semiconductors; 7. Photo-induced defect effects in devices; References; Index.

  5. Collective Calcium Signaling of Defective Multicellular Networks

    NASA Astrophysics Data System (ADS)

    Potter, Garrett; Sun, Bo

    2015-03-01

    A communicating multicellular network processes environmental cues into collective cellular dynamics. We have previously demonstrated that, when excited by extracellular ATP, fibroblast monolayers generate correlated calcium dynamics modulated by both the stimuli and gap junction communication between the cells. However, just as a well-connected neural network may be compromised by abnormal neurons, a tissue monolayer can also be defective with cancer cells, which typically have down regulated gap junctions. To understand the collective cellular dynamics in a defective multicellular network we have studied the calcium signaling of co-cultured breast cancer cells and fibroblast cells in various concentrations of ATP delivered through microfluidic devices. Our results demonstrate that cancer cells respond faster, generate singular spikes, and are more synchronous across all stimuli concentrations. Additionally, fibroblast cells exhibit persistent calcium oscillations that increase in regularity with greater stimuli. To interpret these results we quantitatively analyzed the immunostaining of purigenic receptors and gap junction channels. The results confirm our hypothesis that collective dynamics are mainly determined by the availability of gap junction communications.

  6. Evolutionary Design of a Robotic Material Defect Detection System

    NASA Technical Reports Server (NTRS)

    Ballard, Gary; Howsman, Tom; Craft, Mike; ONeil, Daniel; Steincamp, Jim; Howell, Joe T. (Technical Monitor)

    2002-01-01

    During the post-flight inspection of SSME engines, several inaccessible regions must be disassembled to inspect for defects such as cracks, scratches, gouges, etc. An improvement to the inspection process would be the design and development of very small robots capable of penetrating these inaccessible regions and detecting the defects. The goal of this research was to utilize an evolutionary design approach for the robotic detection of these types of defects. A simulation and visualization tool was developed prior to receiving the hardware as a development test bed. A small, commercial off-the-shelf (COTS) robot was selected from several candidates as the proof of concept robot. The basic approach to detect the defects was to utilize Cadmium Sulfide (CdS) sensors to detect changes in contrast of an illuminated surface. A neural network, optimally designed utilizing a genetic algorithm, was employed to detect the presence of the defects (cracks). By utilization of the COTS robot and US sensors, the research successfully demonstrated that an evolutionarily designed neural network can detect the presence of surface defects.

  7. Additive manufacturing for in situ repair of osteochondral defects.

    PubMed

    Cohen, Daniel L; Lipton, Jeffrey I; Bonassar, Lawrence J; Lipson, Hod

    2010-09-01

    Tissue engineering holds great promise for injury repair and replacement of defective body parts. While a number of techniques exist for creating living biological constructs in vitro, none have been demonstrated for in situ repair. Using novel geometric feedback-based approaches and through development of appropriate printing-material combinations, we demonstrate the in situ repair of both chondral and osteochondral defects that mimic naturally occurring pathologies. A calf femur was mounted in a custom jig and held within a robocasting-based additive manufacturing (AM) system. Two defects were induced: one a cartilage-only representation of a grade IV chondral lesion and the other a two-material bone and cartilage fracture of the femoral condyle. Alginate hydrogel was used for the repair of cartilage; a novel formulation of demineralized bone matrix was used for bone repair. Repair prints for both defects had mean surface errors less than 0.1 mm. For the chondral defect, 42.8+/-2.6% of the surface points had errors that were within a clinically acceptable error range; however, with 1 mm path planning shift, an estimated approximately 75% of surface points could likely fall within the benchmark envelope. For the osteochondral defect, 83.6+/-2.7% of surface points had errors that were within clinically acceptable limits. In addition to implications for minimally invasive AM-based clinical treatments, these proof-of-concept prints are some of the only in situ demonstrations to-date, wherein the substrate geometry was unknown a priori. The work presented herein demonstrates in situ AM, suggests potential biomedical applications and also explores in situ-specific issues, including geometric feedback, material selection and novel path planning techniques.

  8. Designing using manufacturing features

    NASA Astrophysics Data System (ADS)

    Szecsi, T.; Hoque, A. S. M.

    2012-04-01

    This paper presents a design system that enables the composition of a part using manufacturing features. Features are selected from feature libraries. Upon insertion, the system ensures that the feature does not contradict the design-for-manufacture rules. This helps eliminating costly manufacturing problems. The system is developed as an extension to a commercial CAD/CAM system Pro/Engineer.

  9. Algorithms and applications of aberration correction and American standard-based digital evaluation in surface defects evaluating system

    NASA Astrophysics Data System (ADS)

    Wu, Fan; Cao, Pin; Yang, Yongying; Li, Chen; Chai, Huiting; Zhang, Yihui; Xiong, Haoliang; Xu, Wenlin; Yan, Kai; Zhou, Lin; Liu, Dong; Bai, Jian; Shen, Yibing

    2016-11-01

    The inspection of surface defects is one of significant sections of optical surface quality evaluation. Based on microscopic scattering dark-field imaging, sub-aperture scanning and stitching, the Surface Defects Evaluating System (SDES) can acquire full-aperture image of defects on optical elements surface and then extract geometric size and position information of defects with image processing such as feature recognization. However, optical distortion existing in the SDES badly affects the inspection precision of surface defects. In this paper, a distortion correction algorithm based on standard lattice pattern is proposed. Feature extraction, polynomial fitting and bilinear interpolation techniques in combination with adjacent sub-aperture stitching are employed to correct the optical distortion of the SDES automatically in high accuracy. Subsequently, in order to digitally evaluate surface defects with American standard by using American military standards MIL-PRF-13830B to judge the surface defects information obtained from the SDES, an American standard-based digital evaluation algorithm is proposed, which mainly includes a judgment method of surface defects concentration. The judgment method establishes weight region for each defect and adopts the method of overlap of weight region to calculate defects concentration. This algorithm takes full advantage of convenience of matrix operations and has merits of low complexity and fast in running, which makes itself suitable very well for highefficiency inspection of surface defects. Finally, various experiments are conducted and the correctness of these algorithms are verified. At present, these algorithms have been used in SDES.

  10. Lithographic plane review (LPR) for sub-32nm mask defect disposition

    NASA Astrophysics Data System (ADS)

    Tolani, Vikram; Peng, Danping; He, Lin; Hwa, George; Chang, Hsien-Min; Dai, Grace; Corcoran, Noel; Dam, Thuc; Pang, Linyong; Tuo, Laurent C.; Chen, C. J.; Lai, Rick

    2010-09-01

    As optical lithography continues to extend into low-k1 regime, resolution of mask patterns under mask inspection optical conditions continues to diminish. Furthermore, as mask complexity and MEEF has also increased, it requires detecting even smaller defects in the already narrower pitch mask patterns. This leaves the mask inspection engineer with the option to either purchase a higher resolution mask inspection tool or increase the detector sensitivity on the existing inspection system or maybe even both. In order to meet defect sensitivity requirements in critical features of sub-32nm node designs, increasing sensitivity typically results in increased nuisance (i.e., small sub-specification) defect detection by 5-20X defects making post-inspection defect review non-manufacturable. As a solution for automatically dispositioning the increased number of nuisance and real defects detected at higher inspection sensitivity, Luminescent has successfully extended Inverse Lithography Technology (ILT) and its patented level-set methods to reconstruct the defective mask from its inspection image, and then perform simulated AIMS dispositioning on the reconstructed mask. In this technique, named Lithographic Plane Review (LPR), inspection transmitted and reflected light images of the test (i.e. defect) and reference (i.e., corresponding defect-free) regions are provided to the "inversion" engine which then computes the corresponding test and reference mask patterns. An essential input to this engine is a well calibrated model incorporating inspection tool optics, mask processing and 3D effects, and also the subsequent AIMS tool optics to be able to then simulate the aerial image impact of the defects. This flow is equivalent to doing an actual AIMS tool measurement of every defect detected during mask inspection, while at the same time maintaining inspection at high enough resolution. What makes this product usable in mask volume production is the high degree of accuracy of

  11. Congenital heart defects and medical imaging.

    PubMed

    Gehin, Connie; Ragsdale, Lisa

    2013-01-01

    Radiologic technologists perform imaging studies that are useful in the diagnosis of congenital heart defects in infants and adults. These studies also help to monitor congenital heart defect repairs in adults. This article describes the development and functional anatomy of the heart, along with the epidemiology and anatomy of congenital heart defects. It also discusses the increasing population of adults who have congenital heart defects and the most effective modalities for diagnosing, evaluating, and monitoring congenital heart defects.

  12. Patterns of Dysmorphic Features in Schizophrenia

    PubMed Central

    Scutt, L.E.; Chow, E.W.C.; Weksberg, R.; Honer, W.G.; Bassett, Anne S.

    2011-01-01

    Congenital dysmorphic features are prevalent in schizophrenia and may reflect underlying neurodevelopmental abnormalities. A cluster analysis approach delineating patterns of dysmorphic features has been used in genetics to classify individuals into more etiologically homogeneous subgroups. In the present study, this approach was applied to schizophrenia, using a sample with a suspected genetic syndrome as a testable model. Subjects (n = 159) with schizophrenia or schizoaffective disorder were ascertained from chronic patient populations (random, n=123) or referred with possible 22q11 deletion syndrome (referred, n = 36). All subjects were evaluated for presence or absence of 70 reliably assessed dysmorphic features, which were used in a three-step cluster analysis. The analysis produced four major clusters with different patterns of dysmorphic features. Significant between-cluster differences were found for rates of 37 dysmorphic features (P < 0.05), median number of dysmorphic features (P = 0.0001), and validating features not used in the cluster analysis: mild mental retardation (P = 0.001) and congenital heart defects (P = 0.002). Two clusters (1 and 4) appeared to represent more developmental subgroups of schizophrenia with elevated rates of dysmorphic features and validating features. Cluster 1 (n = 27) comprised mostly referred subjects. Cluster 4 (n= 18) had a different pattern of dysmorphic features; one subject had a mosaic Turner syndrome variant. Two other clusters had lower rates and patterns of features consistent with those found in previous studies of schizophrenia. Delineating patterns of dysmorphic features may help identify subgroups that could represent neurodevelopmental forms of schizophrenia with more homogeneous origins. PMID:11803519

  13. Orientational order of motile defects in active nematics

    DOE PAGES

    DeCamp, Stephen J.; Redner, Gabriel S.; Baskaran, Aparna; ...

    2015-08-17

    The study of equilibrium liquid crystals has led to fundamental insights into the nature of ordered materials, as well as many practical applications such as display technologies. Active nematics are a fundamentally different class of liquid crystals, which are driven away from equilibrium by the autonomous motion of their constituent rodlike particles. This internally-generated activity powers the continuous creation and annihilation of topological defects, leading to complex streaming flows whose chaotic dynamics appear to destroy long-range order. Here, we study these dynamics in experimental and computational realizations of active nematics. By tracking thousands of defects over centimeter distances in microtubule-basedmore » active nematics, we identify a non-equilibrium phase characterized by system-spanning orientational order of defects. This emergent order persists over hours despite defect lifetimes of only seconds. Lastly, similar dynamical structures are observed in coarse-grained simulations, suggesting that defect-ordered phases are a generic feature of active nematics.« less

  14. Predicting the Occurrence of Cosmetic Defects in Automotive Skin Panels

    SciTech Connect

    Hazra, S.; Williams, D.; Roy, R.; Aylmore, R.; Allen, M.; Hollingdale, D.

    2011-05-04

    The appearance of defects such as 'hollows' and 'shock lines' can affect the perceived quality and attractiveness of automotive skin panels. These defects are the result of the stamping process and appear as small, localized deviations from the intended styling of the panels. Despite their size, they become visually apparent after the application of paint and the perceived quality of a panel may become unacceptable. Considerable time is then dedicated to minimizing their occurrence through tool modifications. This paper will investigate the use of the wavelet transform as a tool to analyze physically measured panels. The transform has two key aspects. The first is its ability to distinguish small scale local defects from large scale styling curvature. The second is its ability to characterize the shape of a defect in terms of its wavelength and a 'correlation value'. The two features of the transform enable it to be used as a tool for locating and predicting the severity of defects. The paper will describe the transform and illustrate its application on test cases.

  15. Simple Buoyancy Demonstrations Using Saltwater.

    ERIC Educational Resources Information Center

    Cosby, Ronald M.; Petry, Douglas E.

    1989-01-01

    Discusses the use of saline solutions for demonstrations of buoyancy showing oscillations of the Cartesian diver. Describes the physical principles, preparation, and instructional uses for the demonstration. (YP)

  16. Environmental causes of enamel defects.

    PubMed

    Brook, A H; Fearne, J M; Smith, J M

    1997-01-01

    A large number of causes of enamel defects, both environmental and genetic, have been described. However, many of these are derived from case histories and studies of individual conditions. What is needed now is a systematic investigation of the problem. The first requirement in exploring the aetiology further is the standardization of both the clinical diagnosis and the descriptive terminology. This has been provided by the Fédération Dentaire Internationale Developmental Defects of Enamel Index. Comparing studies using standardized methods, including this index, has highlighted areas for closer investigation. The total prevalence of enamel defects in a population needs to be established as a baseline for studies on aetiology. Sixty-eight per cent of 1518 school children in London have enamel defects in the permanent dentition, with 10.5% having 10 or more teeth affected and 14.6% having hypoplasia, i.e. missing enamel. These findings are in contrast to the 37% with hypoplasia found in a group of third to fifth century Romano-Britons from Dorset, England, suggesting further consideration of possible environmental and genetic differences between the two populations. An overall long-term study of dental development in low birth weight children has shown significantly more (P < 0.001) enamel defects related to major health problems during the neonatal period. By using standardized, reproducible criteria in prevalence studies to gain an overview of the problem and then studying specific groups or conditions, it is possible to identify general and specific factors in the aetiology of enamel defects and investigate further the varying role of genetic and environmental effects.

  17. Interface effects on calculated defect levels for oxide defects

    NASA Astrophysics Data System (ADS)

    Edwards, Arthur; Barnaby, Hugh; Schultz, Peter; Pineda, Andrew

    2014-03-01

    Density functional theory (DFT) has had impressive recent success predicting defect levels in insulators and semiconductors [Schultz and von Lillienfeld, 2009]. Such success requires care in accounting for long-range electrostatic effects. Recently, Komsa and Pasquarello have started to address this problem in systems with interfaces. We report a multiscale technique for calculating electrostatic energies for charged defects in oxide of the metal-oxide-silicon (MOS) system, but where account is taken of substrate doping density, oxide thickness, and gate bias. We use device modeling to calculate electric fields for a point charge a fixed distance from the interface, and used the field to numerically calculate the long-range electrostatic interactions. We find, for example, that defect levels in the oxide do depend on both the magnitude and the polarity the substrate doping density. Furthermore, below 20 Å, oxide thickness also has significant effects. So, transferring results directly from bulk calculations leads to inaccuracies up to 0.5 eV- half of the silicon band gap. We will present trends in defect levels as a function of device parameters. We show that these results explain previous experimental results, and we comment on their potential impact on models for NBTI. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the United States Department of Energy's National Nuclear Security Administration under co.

  18. Fast in-situ photoluminescence analysis for a recombination parameterization of the fast BO defect component in silicon

    NASA Astrophysics Data System (ADS)

    Niewelt, T.; Mägdefessel, S.; Schubert, M. C.

    2016-08-01

    Light-induced degradation due to BO defects in silicon consists of a fast initial decay within a few seconds followed by a slower decay within hours to days. Determination of injection dependent charge carrier lifetime curves during the initial decay is challenging due to this short timeframe. We have developed a suitable measurement technique based on in situ photoluminescence measurements and present results of our studies of the fast degradation component. The temporal evolution of the recombination activity is studied and assessed by means of a two-level Shockley-Read-Hall statistics. A quadratic dependence of the fast defect activation on the hole concentration during illumination is demonstrated. We suggest a new parameterization of the recombination activity introduced by fast-formed BO defects featuring energy levels 0.34 eV below the conduction band and 0.31 eV above the valence band. The capture asymmetry ratio determined for the donor level of 18.1 is significantly smaller than previous parameterizations in literature suggest.

  19. An approach for defect visualization and identification in composite plate structures using air-coupled guided ultrasound

    NASA Astrophysics Data System (ADS)

    Panda, Rabi Sankar; Rajagopal, Prabhu; Balasubramaniam, Krishnan

    2015-03-01

    Composite materials are today widely used in engineering applications because of superior strength-weight ratios offered by them as well as high structural performance and corrosion resistance. However defects such as fibre breakage, matrix cracking, de-bonding and delaminations in composites impact their structural integrity and reliability negatively and NDE techniques to rapidly identify such defects are valuable. Ultrasonic guided waves have over the years emerged as attractive tools for scanning of large structures and recently they have been considered for rapid inspection of plate and pipe installations. Air-coupled ultrasound for generation of Lamb waves is particularly attractive for composite applications in view of the non-contact inspection offered, as well as the possibilities for rapid mechanized scanning. In this paper we present damage identification and visualisation approaches for quasi-isotropic composite plate structures, based on air-coupled plate guided ultrasonic (Lamb) waves. In the implementation demonstrated, an 8-layered quasi-isotropic [0/+45/-45/90]s glass fibre reinforced plastics (GFRP) composite plate is interrogated using air-coupled pitch-catch guided ultrasound. Propagation of Lamb waves in the laminates and their interaction with delaminations of different sizes at various locations along the structure are studied using 3D finite element (FE) analysis. The visualization approach is validated using experiments, leading to quantitative predictions of defect parameters such as sizing, location and depth. The approach is also extended for the inspection of complex composite structural features such as I- and T-sections.

  20. Systematical Evaluation of Mechanically Strong 3D Printed Diluted magnesium Doping Wollastonite Scaffolds on Osteogenic Capacity in Rabbit Calvarial Defects

    PubMed Central

    Sun, Miao; Liu, An; Shao, Huifeng; Yang, Xianyan; Ma, Chiyuan; Yan, Shigui; Liu, Yanming; He, Yong; Gou, Zhongru

    2016-01-01

    Wollastonite (CaSiO3; CSi) ceramic is a promising bioactive material for bone defect repair due to slightly fast degradation of its porous constructs in vivo. In our previous strategy some key features of CSi ceramic have been significantly improved by dilute magnesium doping for regulating mechanical properties and biodegradation. Here we demonstrate that 6 ~ 14% of Ca substituted by Mg in CSi (CSi-Mgx, x = 6, 10, 14) can enhance the mechanical strength (>40 MPa) but not compromise biological performances of the 3D printed porous scaffolds with open porosity of 60‒63%. The in vitro cell culture tests in vitro indicated that the dilute Mg doping into CSi was beneficial for ALP activity and high expression of osteogenic marker genes of MC3T3-E1 cells in the scaffolds. A good bone tissue regeneration response and elastoplastic response in mechanical strength in vivo were determined after implantation in rabbit calvarial defects for 6‒12 weeks. Particularly, the CSi-Mg10 and CSi-Mg14 scaffolds could enhance new bone regeneration with a significant increase of newly formed bone tissue (18 ~ 22%) compared to the pure CSi (~14%) at 12 weeks post-implantation. It is reasonable to consider that, therefore, such CSi-Mgx scaffolds possessing excellent strength and reasonable degradability are promising for bone reconstruction in thin-wall bone defects. PMID:27658481