Sample records for source-mask optimization smo

  1. The impact of realistic source shape and flexibility on source mask optimization

    NASA Astrophysics Data System (ADS)

    Aoyama, Hajime; Mizuno, Yasushi; Hirayanagi, Noriyuki; Kita, Naonori; Matsui, Ryota; Izumi, Hirohiko; Tajima, Keiichi; Siebert, Joachim; Demmerle, Wolfgang; Matsuyama, Tomoyuki

    2013-04-01

    Source mask optimization (SMO) is widely used to make state-of-the-art semiconductor devices in high volume manufacturing. To realize mature SMO solutions in production, the Intelligent Illuminator, which is an illumination system on Nikon scanner, is useful because it can provide generation of freeform sources with high fidelity to the target. Proteus SMO, which employs co-optimization method and an insertion of validation with mask 3D effect and resist properties for an accurate prediction of wafer printing, can take into account the properties of Intelligent Illuminator. We investigate an impact of the source properties on the SMO to pattern of a static-random access memory. Quality of a source made on the scanner compared to the SMO target is evaluated with in-situ measurement and aerial image simulation using its measurement data. Furthermore we discuss an evaluation of a universality of the source to use it in multiple scanners with a validation with estimated value of scanner errors.

  2. Robust source and mask optimization compensating for mask topography effects in computational lithography.

    PubMed

    Li, Jia; Lam, Edmund Y

    2014-04-21

    Mask topography effects need to be taken into consideration for a more accurate solution of source mask optimization (SMO) in advanced optical lithography. However, rigorous 3D mask models generally involve intensive computation and conventional SMO fails to manipulate the mask-induced undesired phase errors that degrade the usable depth of focus (uDOF) and process yield. In this work, an optimization approach incorporating pupil wavefront aberrations into SMO procedure is developed as an alternative to maximize the uDOF. We first design the pupil wavefront function by adding primary and secondary spherical aberrations through the coefficients of the Zernike polynomials, and then apply the conjugate gradient method to achieve an optimal source-mask pair under the condition of aberrated pupil. We also use a statistical model to determine the Zernike coefficients for the phase control and adjustment. Rigorous simulations of thick masks show that this approach provides compensation for mask topography effects by improving the pattern fidelity and increasing uDOF.

  3. Extension of optical lithography by mask-litho integration with computational lithography

    NASA Astrophysics Data System (ADS)

    Takigawa, T.; Gronlund, K.; Wiley, J.

    2010-05-01

    Wafer lithography process windows can be enlarged by using source mask co-optimization (SMO). Recently, SMO including freeform wafer scanner illumination sources has been developed. Freeform sources are generated by a programmable illumination system using a micro-mirror array or by custom Diffractive Optical Elements (DOE). The combination of freeform sources and complex masks generated by SMO show increased wafer lithography process window and reduced MEEF. Full-chip mask optimization using source optimized by SMO can generate complex masks with small variable feature size sub-resolution assist features (SRAF). These complex masks create challenges for accurate mask pattern writing and low false-defect inspection. The accuracy of the small variable-sized mask SRAF patterns is degraded by short range mask process proximity effects. To address the accuracy needed for these complex masks, we developed a highly accurate mask process correction (MPC) capability. It is also difficult to achieve low false-defect inspections of complex masks with conventional mask defect inspection systems. A printability check system, Mask Lithography Manufacturability Check (M-LMC), is developed and integrated with 199-nm high NA inspection system, NPI. M-LMC successfully identifies printable defects from all of the masses of raw defect images collected during the inspection of a complex mask. Long range mask CD uniformity errors are compensated by scanner dose control. A mask CD uniformity error map obtained by mask metrology system is used as input data to the scanner. Using this method, wafer CD uniformity is improved. As reviewed above, mask-litho integration technology with computational lithography is becoming increasingly important.

  4. Systematic study of source mask optimization and verification flows

    NASA Astrophysics Data System (ADS)

    Ben, Yu; Latypov, Azat; Chua, Gek Soon; Zou, Yi

    2012-06-01

    Source mask optimization (SMO) emerged as powerful resolution enhancement technique (RET) for advanced technology nodes. However, there is a plethora of flow and verification metrics in the field, confounding the end user of the technique. Systemic study of different flows and the possible unification thereof is missing. This contribution is intended to reveal the pros and cons of different SMO approaches and verification metrics, understand the commonality and difference, and provide a generic guideline for RET selection via SMO. The paper discusses 3 different type of variations commonly arise in SMO, namely pattern preparation & selection, availability of relevant OPC recipe for freeform source and finally the metrics used in source verification. Several pattern selection algorithms are compared and advantages of systematic pattern selection algorithms are discussed. In the absence of a full resist model for SMO, alternative SMO flow without full resist model is reviewed. Preferred verification flow with quality metrics of DOF and MEEF is examined.

  5. Joint optimization of source, mask, and pupil in optical lithography

    NASA Astrophysics Data System (ADS)

    Li, Jia; Lam, Edmund Y.

    2014-03-01

    Mask topography effects need to be taken into consideration for more advanced resolution enhancement techniques in optical lithography. However, rigorous 3D mask model achieves high accuracy at a large computational cost. This work develops a combined source, mask and pupil optimization (SMPO) approach by taking advantage of the fact that pupil phase manipulation is capable of partially compensating for mask topography effects. We first design the pupil wavefront function by incorporating primary and secondary spherical aberration through the coefficients of the Zernike polynomials, and achieve optimal source-mask pair under the condition of aberrated pupil. Evaluations against conventional source mask optimization (SMO) without incorporating pupil aberrations show that SMPO provides improved performance in terms of pattern fidelity and process window sizes.

  6. Impact of topographic mask models on scanner matching solutions

    NASA Astrophysics Data System (ADS)

    Tyminski, Jacek K.; Pomplun, Jan; Renwick, Stephen P.

    2014-03-01

    Of keen interest to the IC industry are advanced computational lithography applications such as Optical Proximity Correction of IC layouts (OPC), scanner matching by optical proximity effect matching (OPEM), and Source Optimization (SO) and Source-Mask Optimization (SMO) used as advanced reticle enhancement techniques. The success of these tasks is strongly dependent on the integrity of the lithographic simulators used in computational lithography (CL) optimizers. Lithographic mask models used by these simulators are key drivers impacting the accuracy of the image predications, and as a consequence, determine the validity of these CL solutions. Much of the CL work involves Kirchhoff mask models, a.k.a. thin masks approximation, simplifying the treatment of the mask near-field images. On the other hand, imaging models for hyper-NA scanner require that the interactions of the illumination fields with the mask topography be rigorously accounted for, by numerically solving Maxwell's Equations. The simulators used to predict the image formation in the hyper-NA scanners must rigorously treat the masks topography and its interaction with the scanner illuminators. Such imaging models come at a high computational cost and pose challenging accuracy vs. compute time tradeoffs. Additional complication comes from the fact that the performance metrics used in computational lithography tasks show highly non-linear response to the optimization parameters. Finally, the number of patterns used for tasks such as OPC, OPEM, SO, or SMO range from tens to hundreds. These requirements determine the complexity and the workload of the lithography optimization tasks. The tools to build rigorous imaging optimizers based on first-principles governing imaging in scanners are available, but the quantifiable benefits they might provide are not very well understood. To quantify the performance of OPE matching solutions, we have compared the results of various imaging optimization trials obtained with Kirchhoff mask models to those obtained with rigorous models involving solutions of Maxwell's Equations. In both sets of trials, we used sets of large numbers of patterns, with specifications representative of CL tasks commonly encountered in hyper-NA imaging. In this report we present OPEM solutions based on various mask models and discuss the models' impact on hyper- NA scanner matching accuracy. We draw conclusions on the accuracy of results obtained with thin mask models vs. the topographic OPEM solutions. We present various examples representative of the scanner image matching for patterns representative of the current generation of IC designs.

  7. Application of resist-profile-aware source optimization in 28 nm full chip optical proximity correction

    NASA Astrophysics Data System (ADS)

    Zhu, Jun; Zhang, David Wei; Kuo, Chinte; Wang, Qing; Wei, Fang; Zhang, Chenming; Chen, Han; He, Daquan; Hsu, Stephen D.

    2017-07-01

    As technology node shrinks, aggressive design rules for contact and other back end of line (BEOL) layers continue to drive the need for more effective full chip patterning optimization. Resist top loss is one of the major challenges for 28 nm and below technology nodes, which can lead to post-etch hotspots that are difficult to predict and eventually degrade the process window significantly. To tackle this problem, we used an advanced programmable illuminator (FlexRay) and Tachyon SMO (Source Mask Optimization) platform to make resistaware source optimization possible, and it is proved to greatly improve the imaging contrast, enhance focus and exposure latitude, and minimize resist top loss thus improving the yield.

  8. RET selection on state-of-the-art NAND flash

    NASA Astrophysics Data System (ADS)

    Lafferty, Neal V.; He, Yuan; Pei, Jinhua; Shao, Feng; Liu, QingWei; Shi, Xuelong

    2015-03-01

    We present results generated using a new gauge-based Resolution Enhancement Technique (RET) Selection flow during the technology set up phase of a 3x-node NAND Flash product. As a testcase, we consider a challenging critical level for this ash product. The RET solutions include inverse lithography technology (ILT) optimized masks with sub-resolution assist features (SRAF) and companion illumination sources developed using a new pixel based Source Mask Optimization (SMO) tool that uses measurement gauges as a primary input. The flow includes verification objectives which allow tolerancing of particular measurement gauges based on lithographic criteria. Relative importance for particular gauges may also be set, to aid in down-selection from several candidate sources. The end result is a sensitive, objective score of RET performance. Using these custom-defined importance metrics, decisions on the final RET style can be made in an objective way.

  9. Monte Carlo sensitivity analysis of EUV mask reflectivity and its impact on OPC accuracy

    NASA Astrophysics Data System (ADS)

    Chen, Yulu; Wood, Obert; Rankin, Jed; Gullikson, Eric; Meyer-Ilse, Julia; Sun, Lei; Qi, Zhengqing John; Goodwin, Francis; Kye, Jongwook

    2017-03-01

    Unlike optical masks which are transmissive optical elements, use of extreme ultraviolet (EUV) radiation requires a reflective mask structure - a multi-layer coating consisting of alternating layers of high-Z (wave impedance) and low-Z materials that provide enhanced reflectivity over a narrow wavelength band peaked at the Bragg wavelength.1 Absorber side wall angle, corner rounding,2 surface roughness,3 and defects4 affect mask performance, but even seemingly simple parameters like bulk reflectivity on mirror and absorber surfaces can have a profound influence on imaging. For instance, using inaccurate reflectivity values at small and large incident angles would diminish the benefits of source mask co-optimization (SMO) and result in larger than expected pattern shifts. The goal of our work is to calculate the variation in mask reflectivity due to various sources of inaccuracies using Monte Carlo simulations. Such calculation is necessary as small changes in the thickness and optical properties of the high-Z and low-Z materials can cause substantial variations in reflectivity. This is further complicated by undesirable intermixing between the two materials used to create the reflector.5 One of the key contributors to mask reflectivity fluctuation is identified to be the intermixing layer thickness. We also investigate the impacts on OPC when the wrong mask information is provided, and evaluate the deterioration of overlapping process window. For a hypothetical N7 via layer, the lack of accurate mask information costs 25% of the depth of focus at 5% exposure latitude. Our work would allow the determination of major contributors to mask reflectivity variation, drive experimental efforts of measuring such contributors, provide strategies to optimize mask reflectivity, and quantize the OPC errors due to imperfect mask modeling.

  10. Layout optimization of DRAM cells using rigorous simulation model for NTD

    NASA Astrophysics Data System (ADS)

    Jeon, Jinhyuck; Kim, Shinyoung; Park, Chanha; Yang, Hyunjo; Yim, Donggyu; Kuechler, Bernd; Zimmermann, Rainer; Muelders, Thomas; Klostermann, Ulrich; Schmoeller, Thomas; Do, Mun-hoe; Choi, Jung-Hoe

    2014-03-01

    DRAM chip space is mainly determined by the size of the memory cell array patterns which consist of periodic memory cell features and edges of the periodic array. Resolution Enhancement Techniques (RET) are used to optimize the periodic pattern process performance. Computational Lithography such as source mask optimization (SMO) to find the optimal off axis illumination and optical proximity correction (OPC) combined with model based SRAF placement are applied to print patterns on target. For 20nm Memory Cell optimization we see challenges that demand additional tool competence for layout optimization. The first challenge is a memory core pattern of brick-wall type with a k1 of 0.28, so it allows only two spectral beams to interfere. We will show how to analytically derive the only valid geometrically limited source. Another consequence of two-beam interference limitation is a "super stable" core pattern, with the advantage of high depth of focus (DoF) but also low sensitivity to proximity corrections or changes of contact aspect ratio. This makes an array edge correction very difficult. The edge can be the most critical pattern since it forms the transition from the very stable regime of periodic patterns to non-periodic periphery, so it combines the most critical pitch and highest susceptibility to defocus. Above challenge makes the layout correction to a complex optimization task demanding a layout optimization that finds a solution with optimal process stability taking into account DoF, exposure dose latitude (EL), mask error enhancement factor (MEEF) and mask manufacturability constraints. This can only be achieved by simultaneously considering all criteria while placing and sizing SRAFs and main mask features. The second challenge is the use of a negative tone development (NTD) type resist, which has a strong resist effect and is difficult to characterize experimentally due to negative resist profile taper angles that perturb CD at bottom characterization by scanning electron microscope (SEM) measurements. High resist impact and difficult model data acquisition demand for a simulation model that hat is capable of extrapolating reliably beyond its calibration dataset. We use rigorous simulation models to provide that predictive performance. We have discussed the need of a rigorous mask optimization process for DRAM contact cell layout yielding mask layouts that are optimal in process performance, mask manufacturability and accuracy. In this paper, we have shown the step by step process from analytical illumination source derivation, a NTD and application tailored model calibration to layout optimization such as OPC and SRAF placement. Finally the work has been verified with simulation and experimental results on wafer.

  11. Improving 130nm node patterning using inverse lithography techniques for an analog process

    NASA Astrophysics Data System (ADS)

    Duan, Can; Jessen, Scott; Ziger, David; Watanabe, Mizuki; Prins, Steve; Ho, Chi-Chien; Shu, Jing

    2018-03-01

    Developing a new lithographic process routinely involves usage of lithographic toolsets and much engineering time to perform data analysis. Process transfers between fabs occur quite often. One of the key assumptions made is that lithographic settings are equivalent from one fab to another and that the transfer is fluid. In some cases, that is far from the truth. Differences in tools can change the proximity effect seen in low k1 imaging processes. If you use model based optical proximity correction (MBOPC), then a model built in one fab will not work under the same conditions at another fab. This results in many wafers being patterned to try and match a baseline response. Even if matching is achieved, there is no guarantee that optimal lithographic responses are met. In this paper, we discuss the approach used to transfer and develop new lithographic processes and define MBOPC builds for the new lithographic process in Fab B which was transferred from a similar lithographic process in Fab A. By using PROLITHTM simulations to match OPC models for each level, minimal downtime in wafer processing was observed. Source Mask Optimization (SMO) was also used to optimize lithographic processes using novel inverse lithography techniques (ILT) to simultaneously optimize mask bias, depth of focus (DOF), exposure latitude (EL) and mask error enhancement factor (MEEF) for critical designs for each level.

  12. In-die mask registration measurement on 28nm-node and beyond

    NASA Astrophysics Data System (ADS)

    Chen, Shen Hung; Cheng, Yung Feng; Chen, Ming Jui

    2013-09-01

    As semiconductor go to smaller node, the critical dimension (CD) of process become more and more small. For lithography, RET (Resolution Enhancement Technology) applications can be used for wafer printing of smaller CD/pitch on 28nm node and beyond. SMO (Source Mask Optimization), DPT (Double Patterning Technology) and SADP (Self-Align Double Patterning) can provide lower k1 value for lithography. In another way, image placement error and overlay control also become more and more important for smaller chip size (advanced node). Mask registration (image placement error) and mask overlay are important factors to affect wafer overlay control/performance especially for DPT or SADP. In traditional method, the designed registration marks (cross type, square type) with larger CD were put into scribe-line of mask frame for registration and overlay measurement. However, these patterns are far way from real patterns. It does not show the registration of real pattern directly and is not a convincing method. In this study, the in-die (in-chip) registration measurement is introduced. We extract the dummy patterns that are close to main pattern from post-OPC (Optical Proximity Correction) gds by our desired rule and choose the patterns that distribute over whole mask uniformly. The convergence test shows 100 points measurement has a reliable result.

  13. Photomask quality evaluation using lithography simulation and multi-detector MVM-SEM

    NASA Astrophysics Data System (ADS)

    Ito, Keisuke; Murakawa, Tsutomu; Fukuda, Naoki; Shida, Soichi; Iwai, Toshimichi; Matsumoto, Jun; Nakamura, Takayuki; Matsushita, Shohei; Hagiwara, Kazuyuki; Hara, Daisuke

    2013-06-01

    The detection and management of mask defects which are transferred onto wafer becomes more important day by day. As the photomask patterns becomes smaller and more complicated, using Inverse Lithography Technology (ILT) and Source Mask Optimization (SMO) with Optical Proximity Correction (OPC). To evaluate photomask quality, the current method uses aerial imaging by optical inspection tools. This technique at 1Xnm node has a resolution limit because small defects will be difficult to detect. We already reported the MEEF influence of high-end photomask using wide FOV SEM contour data of "E3630 MVM-SEM®" and lithography simulator "TrueMask® DS" of D2S Inc. in the prior paper [1]. In this paper we evaluate the correlation between our evaluation method and optical inspection tools as ongoing assessment. Also in order to reduce the defect classification work, we can compose the 3 Dimensional (3D) information of defects and can judge whether repairs of defects would be required. Moreover, we confirm the possibility of wafer plane CD measurement based on the combination between E3630 MVM-SEM® and 3D lithography simulation.

  14. Quantitative evaluation of manufacturability and performance for ILT produced mask shapes using a single-objective function

    NASA Astrophysics Data System (ADS)

    Choi, Heon; Wang, Wei-long; Kallingal, Chidam

    2015-03-01

    The continuous scaling of semiconductor devices is quickly outpacing the resolution improvements of lithographic exposure tools and processes. This one-sided progression has pushed optical lithography to its limits, resulting in the use of well-known techniques such as Sub-Resolution Assist Features (SRAF's), Source-Mask Optimization (SMO), and double-patterning, to name a few. These techniques, belonging to a larger category of Resolution Enhancement Techniques (RET), have extended the resolution capabilities of optical lithography at the cost of increasing mask complexity, and therefore cost. One such technique, called Inverse Lithography Technique (ILT), has attracted much attention for its ability to produce the best possible theoretical mask design. ILT treats the mask design process as an inverse problem, where the known transformation from mask to wafer is carried out backwards using a rigorous mathematical approach. One practical problem in the application of ILT is the resulting contour-like mask shapes that must be "Manhattanized" (composed of straight edges and 90-deg corners) in order to produce a manufacturable mask. This conversion process inherently degrades the mask quality as it is a departure from the "optimal mask" represented by the continuously curved shapes produced by ILT. However, simpler masks composed of longer straight edges reduce the mask cost as it lowers the shot count and saves mask writing time during mask fabrication, resulting in a conflict between manufacturability and performance for ILT produced masks1,2. In this study, various commonly used metrics will be combined into an objective function to produce a single number to quantitatively measure a particular ILT solution's ability to balance mask manufacturability and RET performance. Several metrics that relate to mask manufacturing costs (i.e. mask vertex count, ILT computation runtime) are appropriately weighted against metrics that represent RET capability (i.e. process-variation band, edge-placement-error) in order to reflect the desired practical balance. This well-defined scoring system allows direct comparison of several masks with varying degrees of complexities. Using this method, ILT masks produced with increasing mask constraints will be compared, and it will be demonstrated that using the smallest minimum width for mask shapes does not always produce the optimal solution.

  15. A novel methodology for litho-to-etch pattern fidelity correction for SADP process

    NASA Astrophysics Data System (ADS)

    Chen, Shr-Jia; Chang, Yu-Cheng; Lin, Arthur; Chang, Yi-Shiang; Lin, Chia-Chi; Lai, Jun-Cheng

    2017-03-01

    For 2x nm node semiconductor devices and beyond, more aggressive resolution enhancement techniques (RETs) such as source-mask co-optimization (SMO), litho-etch-litho-etch (LELE) and self-aligned double patterning (SADP) are utilized for the low k1 factor lithography processes. In the SADP process, the pattern fidelity is extremely critical since a slight photoresist (PR) top-loss or profile roughness may impact the later core trim process, due to its sensitivity to environment. During the subsequent sidewall formation and core removal processes, the core trim profile weakness may worsen and induces serious defects that affect the final electrical performance. To predict PR top-loss, a rigorous lithography simulation can provide a reference to modify mask layouts; but it takes a much longer run time and is not capable of full-field mask data preparation. In this paper, we first brought out an algorithm which utilizes multi-intensity levels from conventional aerial image simulation to assess the physical profile through lithography to core trim etching steps. Subsequently, a novel correction method was utilized to improve the post-etch pattern fidelity without the litho. process window suffering. The results not only matched PR top-loss in rigorous lithography simulation, but also agreed with post-etch wafer data. Furthermore, this methodology can also be incorporated with OPC and post-OPC verification to improve core trim profile and final pattern fidelity at an early stage.

  16. The capability of lithography simulation based on MVM-SEM® system

    NASA Astrophysics Data System (ADS)

    Yoshikawa, Shingo; Fujii, Nobuaki; Kanno, Koichi; Imai, Hidemichi; Hayano, Katsuya; Miyashita, Hiroyuki; Shida, Soichi; Murakawa, Tsutomu; Kuribara, Masayuki; Matsumoto, Jun; Nakamura, Takayuki; Matsushita, Shohei; Hara, Daisuke; Pang, Linyong

    2015-10-01

    The 1Xnm technology node lithography is using SMO-ILT, NTD or more complex pattern. Therefore in mask defect inspection, defect verification becomes more difficult because many nuisance defects are detected in aggressive mask feature. One key Technology of mask manufacture is defect verification to use aerial image simulator or other printability simulation. AIMS™ Technology is excellent correlation for the wafer and standards tool for defect verification however it is difficult for verification over hundred numbers or more. We reported capability of defect verification based on lithography simulation with a SEM system that architecture and software is excellent correlation for simple line and space.[1] In this paper, we use a SEM system for the next generation combined with a lithography simulation tool for SMO-ILT, NTD and other complex pattern lithography. Furthermore we will use three dimension (3D) lithography simulation based on Multi Vision Metrology SEM system. Finally, we will confirm the performance of the 2D and 3D lithography simulation based on SEM system for a photomask verification.

  17. Reticle decision center: a novel applications platform for enhancing reticle yield and productivity at 10nm technology and beyond

    NASA Astrophysics Data System (ADS)

    Hwa, George; Bugata, Raj; Chiang, Kaiming; Lakkapragada, Suresh; Tolani, Vikram; Gopalakrishnan, Sandhya; Chen, Chun-Jen; Yang, Chin-Ting; Hsu, Sheng-Chang; Tuo, Laurent

    2016-10-01

    In the semiconductor IC manufacturing industry, challenges associated with producing defect-free photomasks have been dramatically increasing. At the 10nm technology node, since the 193nm immersion scanner numerical aperture has remained the same 1.35 as in previous nodes, more multi-patterning and aggressive SMO illumination sources are being used to effectively print smaller feature CDs and pitches. To accommodate such specialized sources, more model-based mask OPC and ILT have been used making mask designs very complicated. This in turn makes mask manufacturing very challenging especially for the defect inspection, repair, and metrology processes that need to guarantee defect-free masks. Over the past few years, considerable innovation have been made in the areas of defect inspection and disposition that has ensured continued predictability of mask quality to wafer and final chip yields. The accurate disposition of each mask defect before and after repair has been facilitated by a suite of automated applications such as ADC, LPR, RPG, AIA, etc. that work together with the inspection, repair, and metrology tools and effectively also provide the best possible utilization of the tool capability, capacity and operator resources. In this paper we introduce a new consolidated applications platform called the Reticle Decision Center (RDC) which hosts all these supporting software applications on a centralized server with direct connectivity to mask inspection, repair, metrology tools and more. The paper details how the RDC server is architected to host any application in its native operating system environment and provides for high availability with automatic failover and redundancy. The server along with its host of applications has been tightly integrated with KLA-Tencor's Teron mask inspectors. The paper concludes with showing benefits realized in mask cycle-time and yield as a result of implementing RDC into a high-volume 10nm mask-shop production line.

  18. Antineoplastic Efficacy of Novel Polyamine Analogues in Human Breast Cancer

    DTIC Science & Technology

    2006-06-01

    Davidson, N.E., and Casero, R.A.. Spermine oxidase SMO(PAOh1), not N1-acetylpolyamine oxidase (PAO) is the primary source of cytotoxic H2O2 in...human spermine oxidase SMO(PAOh1). SMO(PAOh1) uses unacetylated spermine as substrate and is inducible by specific polyamine analogs [15,16]. These...technique to find the identical clone termed spermine oxidase (SMO) [16]. The function of SMO(PAOh1) as a spermine oxidase has been confirmed [15,67,68

  19. Inverse lithography using sparse mask representations

    NASA Astrophysics Data System (ADS)

    Ionescu, Radu C.; Hurley, Paul; Apostol, Stefan

    2015-03-01

    We present a novel optimisation algorithm for inverse lithography, based on optimization of the mask derivative, a domain inherently sparse, and for rectilinear polygons, invertible. The method is first developed assuming a point light source, and then extended to general incoherent sources. What results is a fast algorithm, producing manufacturable masks (the search space is constrained to rectilinear polygons), and flexible (specific constraints such as minimal line widths can be imposed). One inherent trick is to treat polygons as continuous entities, thus making aerial image calculation extremely fast and accurate. Requirements for mask manufacturability can be integrated in the optimization without too much added complexity. We also explain how to extend the scheme for phase-changing mask optimization.

  20. Automated parameterization of intermolecular pair potentials using global optimization techniques

    NASA Astrophysics Data System (ADS)

    Krämer, Andreas; Hülsmann, Marco; Köddermann, Thorsten; Reith, Dirk

    2014-12-01

    In this work, different global optimization techniques are assessed for the automated development of molecular force fields, as used in molecular dynamics and Monte Carlo simulations. The quest of finding suitable force field parameters is treated as a mathematical minimization problem. Intricate problem characteristics such as extremely costly and even abortive simulations, noisy simulation results, and especially multiple local minima naturally lead to the use of sophisticated global optimization algorithms. Five diverse algorithms (pure random search, recursive random search, CMA-ES, differential evolution, and taboo search) are compared to our own tailor-made solution named CoSMoS. CoSMoS is an automated workflow. It models the parameters' influence on the simulation observables to detect a globally optimal set of parameters. It is shown how and why this approach is superior to other algorithms. Applied to suitable test functions and simulations for phosgene, CoSMoS effectively reduces the number of required simulations and real time for the optimization task.

  1. Simplex-method based transmission performance optimization for 100G PDM-QPSK systems with non-identical spans

    NASA Astrophysics Data System (ADS)

    Li, Yuanyuan; Gao, Guanjun; Zhang, Jie; Zhang, Kai; Chen, Sai; Yu, Xiaosong; Gu, Wanyi

    2015-06-01

    A simplex-method based optimizing (SMO) strategy is proposed to improve the transmission performance for dispersion uncompensated (DU) coherent optical systems with non-identical spans. Through analytical expression of quality of transmission (QoT), this strategy improves the Q factors effectively, while minimizing the number of erbium-doped optical fiber amplifier (EDFA) that needs to be optimized. Numerical simulations are performed for 100 Gb/s polarization-division multiplexed quadrature phase shift keying (PDM-QPSK) channels over 10-span standard single mode fiber (SSMF) with randomly distributed span-lengths. Compared to the EDFA configurations with complete span loss compensation, the Q factor of the SMO strategy is improved by approximately 1 dB at the optimal transmitter launch power. Moreover, instead of adjusting the gains of all the EDFAs to their optimal value, the number of EDFA that needs to be adjusted for SMO is reduced from 8 to 2, showing much less tuning costs and almost negligible performance degradation.

  2. Generalized SMO algorithm for SVM-based multitask learning.

    PubMed

    Cai, Feng; Cherkassky, Vladimir

    2012-06-01

    Exploiting additional information to improve traditional inductive learning is an active research area in machine learning. In many supervised-learning applications, training data can be naturally separated into several groups, and incorporating this group information into learning may improve generalization. Recently, Vapnik proposed a general approach to formalizing such problems, known as "learning with structured data" and its support vector machine (SVM) based optimization formulation called SVM+. Liang and Cherkassky showed the connection between SVM+ and multitask learning (MTL) approaches in machine learning, and proposed an SVM-based formulation for MTL called SVM+MTL for classification. Training the SVM+MTL classifier requires the solution of a large quadratic programming optimization problem which scales as O(n(3)) with sample size n. So there is a need to develop computationally efficient algorithms for implementing SVM+MTL. This brief generalizes Platt's sequential minimal optimization (SMO) algorithm to the SVM+MTL setting. Empirical results show that, for typical SVM+MTL problems, the proposed generalized SMO achieves over 100 times speed-up, in comparison with general-purpose optimization routines.

  3. CoSMoMVPA: Multi-Modal Multivariate Pattern Analysis of Neuroimaging Data in Matlab/GNU Octave.

    PubMed

    Oosterhof, Nikolaas N; Connolly, Andrew C; Haxby, James V

    2016-01-01

    Recent years have seen an increase in the popularity of multivariate pattern (MVP) analysis of functional magnetic resonance (fMRI) data, and, to a much lesser extent, magneto- and electro-encephalography (M/EEG) data. We present CoSMoMVPA, a lightweight MVPA (MVP analysis) toolbox implemented in the intersection of the Matlab and GNU Octave languages, that treats both fMRI and M/EEG data as first-class citizens. CoSMoMVPA supports all state-of-the-art MVP analysis techniques, including searchlight analyses, classification, correlations, representational similarity analysis, and the time generalization method. These can be used to address both data-driven and hypothesis-driven questions about neural organization and representations, both within and across: space, time, frequency bands, neuroimaging modalities, individuals, and species. It uses a uniform data representation of fMRI data in the volume or on the surface, and of M/EEG data at the sensor and source level. Through various external toolboxes, it directly supports reading and writing a variety of fMRI and M/EEG neuroimaging formats, and, where applicable, can convert between them. As a result, it can be integrated readily in existing pipelines and used with existing preprocessed datasets. CoSMoMVPA overloads the traditional volumetric searchlight concept to support neighborhoods for M/EEG and surface-based fMRI data, which supports localization of multivariate effects of interest across space, time, and frequency dimensions. CoSMoMVPA also provides a generalized approach to multiple comparison correction across these dimensions using Threshold-Free Cluster Enhancement with state-of-the-art clustering and permutation techniques. CoSMoMVPA is highly modular and uses abstractions to provide a uniform interface for a variety of MVP measures. Typical analyses require a few lines of code, making it accessible to beginner users. At the same time, expert programmers can easily extend its functionality. CoSMoMVPA comes with extensive documentation, including a variety of runnable demonstration scripts and analysis exercises (with example data and solutions). It uses best software engineering practices including version control, distributed development, an automated test suite, and continuous integration testing. It can be used with the proprietary Matlab and the free GNU Octave software, and it complies with open source distribution platforms such as NeuroDebian. CoSMoMVPA is Free/Open Source Software under the permissive MIT license. Website: http://cosmomvpa.org Source code: https://github.com/CoSMoMVPA/CoSMoMVPA.

  4. CoSMoMVPA: Multi-Modal Multivariate Pattern Analysis of Neuroimaging Data in Matlab/GNU Octave

    PubMed Central

    Oosterhof, Nikolaas N.; Connolly, Andrew C.; Haxby, James V.

    2016-01-01

    Recent years have seen an increase in the popularity of multivariate pattern (MVP) analysis of functional magnetic resonance (fMRI) data, and, to a much lesser extent, magneto- and electro-encephalography (M/EEG) data. We present CoSMoMVPA, a lightweight MVPA (MVP analysis) toolbox implemented in the intersection of the Matlab and GNU Octave languages, that treats both fMRI and M/EEG data as first-class citizens. CoSMoMVPA supports all state-of-the-art MVP analysis techniques, including searchlight analyses, classification, correlations, representational similarity analysis, and the time generalization method. These can be used to address both data-driven and hypothesis-driven questions about neural organization and representations, both within and across: space, time, frequency bands, neuroimaging modalities, individuals, and species. It uses a uniform data representation of fMRI data in the volume or on the surface, and of M/EEG data at the sensor and source level. Through various external toolboxes, it directly supports reading and writing a variety of fMRI and M/EEG neuroimaging formats, and, where applicable, can convert between them. As a result, it can be integrated readily in existing pipelines and used with existing preprocessed datasets. CoSMoMVPA overloads the traditional volumetric searchlight concept to support neighborhoods for M/EEG and surface-based fMRI data, which supports localization of multivariate effects of interest across space, time, and frequency dimensions. CoSMoMVPA also provides a generalized approach to multiple comparison correction across these dimensions using Threshold-Free Cluster Enhancement with state-of-the-art clustering and permutation techniques. CoSMoMVPA is highly modular and uses abstractions to provide a uniform interface for a variety of MVP measures. Typical analyses require a few lines of code, making it accessible to beginner users. At the same time, expert programmers can easily extend its functionality. CoSMoMVPA comes with extensive documentation, including a variety of runnable demonstration scripts and analysis exercises (with example data and solutions). It uses best software engineering practices including version control, distributed development, an automated test suite, and continuous integration testing. It can be used with the proprietary Matlab and the free GNU Octave software, and it complies with open source distribution platforms such as NeuroDebian. CoSMoMVPA is Free/Open Source Software under the permissive MIT license. Website: http://cosmomvpa.org Source code: https://github.com/CoSMoMVPA/CoSMoMVPA PMID:27499741

  5. Nuclear localization of human spermine oxidase isoforms – possible implications in drug response and disease etiology

    PubMed Central

    Murray-Stewart, Tracy; Wang, Yanlin; Goodwin, Andrew; Hacker, Amy; Meeker, Alan; Casero, Robert A.

    2013-01-01

    The recent discovery of the direct oxidation of spermine via spermine oxidase (SMO) as a mechanism through which specific antitumor polyamine analogues exert their cytotoxic effects has fueled interest in the study of the polyamine catabolic pathway. A major byproduct of spermine oxidation is H2O2, a source of toxic reactive oxygen species. Recent targeted small interfering RNA studies have confirmed that SMO-produced reactive oxygen species are directly responsible for oxidative stress capable of inducing apoptosis and potentially mutagenic DNA damage. In the present study, we describe a second catalytically active splice variant protein of the human spermine oxidase gene, designated SMO5, which exhibits substrate specificities and affinities comparable to those of the originally identified human spermine oxidase-1, SMO/PAOh1, and, as such, is an additional source of H2O2. Importantly, overexpression of either of these SMO isoforms in NCI-H157 human non-small cell lung carcinoma cells resulted in significant localization of SMO protein in the nucleus, as determined by confocal microscopy. Furthermore, cell lines overexpressing either SMO/PAOh1 or SMO5 demonstrated increased spermine oxidation in the nucleus, with accompanying alterations in individual nuclear polyamine concentrations. This increased oxidation of spermine in the nucleus therefore increases the production of highly reactive H2O2 in close proximity to DNA, as well as decreases nuclear spermine levels, thus altering the protective roles of spermine in free radical scavenging and DNA shielding, and resulting in an overall increased potential for oxidative DNA damage in these cells. The results of these studies therefore have considerable significance both with respect to targeting polyamine oxidation as an antineoplastic strategy, and in regard to the potential role of spermine oxidase in inflammation-induced carcinogenesis. PMID:18422650

  6. Electrical comparison of iN7 EUV hybrid and EUV single patterning BEOL metal layers

    NASA Astrophysics Data System (ADS)

    Larivière, Stéphane; Wilson, Christopher J.; Kutrzeba Kotowska, Bogumila; Versluijs, Janko; Decoster, Stefan; Mao, Ming; van der Veen, Marleen H.; Jourdan, Nicolas; El-Mekki, Zaid; Heylen, Nancy; Kesters, Els; Verdonck, Patrick; Béral, Christophe; Van den Heuvel, Dieter; De Bisschop, Peter; Bekaert, Joost; Blanco, Victor; Ciofi, Ivan; Wan, Danny; Briggs, Basoene; Mallik, Arindam; Hendrickx, Eric; Kim, Ryoung-han; McIntyre, Greg; Ronse, Kurt; Bömmels, Jürgen; Tőkei, Zsolt; Mocuta, Dan

    2018-03-01

    The semiconductor scaling roadmap shows the continuous node to node scaling to push Moore's law down to the next generations. In that context, the foundry N5 node requires 32nm metal pitch interconnects for the advanced logic Back- End of Line (BEoL). 193immersion usage now requires self-aligned and/or multiple patterning technique combinations to enable such critical dimension. On the other hand, EUV insertion investigation shows that 32nm metal pitch is still a challenge but, related to process flow complexity, presents some clear motivations. Imec has already evaluated on test chip vehicles with different patterning approaches: 193i SAQP (Self-Aligned Quadruple Patterning), LE3 (triple patterning Litho Etch), tone inversion, EUV SE (Single Exposure) with SMO (Source-mask optimization). Following the run path in the technology development for EUV insertion, imec N7 platform (iN7, corresponding node to the foundry N5) is developed for those BEoL layers. In this paper, following technical motivation and development learning, a comparison between the iArF SAQP/EUV block hybrid integration scheme and a single patterning EUV flow is proposed. These two integration patterning options will be finally compared from current morphological and electrical criteria.

  7. System design and improvement of an emergency department using Simulation-Based Multi-Objective Optimization

    NASA Astrophysics Data System (ADS)

    Goienetxea Uriarte, A.; Ruiz Zúñiga, E.; Urenda Moris, M.; Ng, A. H. C.

    2015-05-01

    Discrete Event Simulation (DES) is nowadays widely used to support decision makers in system analysis and improvement. However, the use of simulation for improving stochastic logistic processes is not common among healthcare providers. The process of improving healthcare systems involves the necessity to deal with trade-off optimal solutions that take into consideration a multiple number of variables and objectives. Complementing DES with Multi-Objective Optimization (SMO) creates a superior base for finding these solutions and in consequence, facilitates the decision-making process. This paper presents how SMO has been applied for system improvement analysis in a Swedish Emergency Department (ED). A significant number of input variables, constraints and objectives were considered when defining the optimization problem. As a result of the project, the decision makers were provided with a range of optimal solutions which reduces considerably the length of stay and waiting times for the ED patients. SMO has proved to be an appropriate technique to support healthcare system design and improvement processes. A key factor for the success of this project has been the involvement and engagement of the stakeholders during the whole process.

  8. Discovery of potent and novel smoothened antagonists via structure-based virtual screening and biological assays.

    PubMed

    Lu, Wenfeng; Zhang, Dihua; Ma, Haikuo; Tian, Sheng; Zheng, Jiyue; Wang, Qin; Luo, Lusong; Zhang, Xiaohu

    2018-05-23

    The Hedgehog (Hh) signaling pathway plays a critical role in controlling patterning, growth and cell migration during embryonic development. Aberrant activation of Hh signaling has been linked to tumorigenesis in various cancers, such as basal cell carcinoma (BCC) and medulloblastoma. As a key member of the Hh pathway, the Smoothened (Smo) receptor, a member of the G protein-coupled receptor (GPCR) family, has emerged as an attractive therapeutic target for the treatment and prevention of human cancers. The recent determination of several crystal structures of Smo in complex with different antagonists offers the possibility to perform structure-based virtual screening for discovering potent Smo antagonists with distinct chemical scaffolds. In this study, based on the two Smo crystal complexes with the best capacity to distinguish the known Smo antagonists from decoys, the molecular docking-based virtual screening was conducted to identify promising Smo antagonists from ChemDiv library. A total of 21 structurally novel and diverse compounds were selected for experimental testing, and six of them exhibited significant inhibitory activity against the Hh pathway activation (IC 50  < 10 μM) in a GRE (Gli-responsive element) reporter gene assay. Specifically, the most potent compound (compound 20: 47 nM) showed comparable Hh signaling inhibition to vismodegib (46 nM). Compound 20 was further confirmed to be a potent Smo antagonist in a fluorescence based competitive binding assay. Optimization using substructure searching method led to the discovery of 12 analogues of compound 20 with decent Hh pathway inhibition activity, including four compounds with IC 50 lower than 1 μM. The important residues uncovered by binding free energy calculation (MM/GBSA) and binding free energy decomposition were highlighted and discussed. These findings suggest that the novel scaffold afforded by compound 20 can be used as a good starting point for further modification/optimization and the clarified interaction patterns may also guide us to find more potent Smo antagonists. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  9. ILT based defect simulation of inspection images accurately predicts mask defect printability on wafer

    NASA Astrophysics Data System (ADS)

    Deep, Prakash; Paninjath, Sankaranarayanan; Pereira, Mark; Buck, Peter

    2016-05-01

    At advanced technology nodes mask complexity has been increased because of large-scale use of resolution enhancement technologies (RET) which includes Optical Proximity Correction (OPC), Inverse Lithography Technology (ILT) and Source Mask Optimization (SMO). The number of defects detected during inspection of such mask increased drastically and differentiation of critical and non-critical defects are more challenging, complex and time consuming. Because of significant defectivity of EUVL masks and non-availability of actinic inspection, it is important and also challenging to predict the criticality of defects for printability on wafer. This is one of the significant barriers for the adoption of EUVL for semiconductor manufacturing. Techniques to decide criticality of defects from images captured using non actinic inspection images is desired till actinic inspection is not available. High resolution inspection of photomask images detects many defects which are used for process and mask qualification. Repairing all defects is not practical and probably not required, however it's imperative to know which defects are severe enough to impact wafer before repair. Additionally, wafer printability check is always desired after repairing a defect. AIMSTM review is the industry standard for this, however doing AIMSTM review for all defects is expensive and very time consuming. Fast, accurate and an economical mechanism is desired which can predict defect printability on wafer accurately and quickly from images captured using high resolution inspection machine. Predicting defect printability from such images is challenging due to the fact that the high resolution images do not correlate with actual mask contours. The challenge is increased due to use of different optical condition during inspection other than actual scanner condition, and defects found in such images do not have correlation with actual impact on wafer. Our automated defect simulation tool predicts printability of defects at wafer level and automates the process of defect dispositioning from images captured using high resolution inspection machine. It first eliminates false defects due to registration, focus errors, image capture errors and random noise caused during inspection. For the remaining real defects, actual mask-like contours are generated using the Calibre® ILT solution [1][2], which is enhanced to predict the actual mask contours from high resolution defect images. It enables accurate prediction of defect contours, which is not possible from images captured using inspection machine because some information is already lost due to optical effects. Calibre's simulation engine is used to generate images at wafer level using scanner optical conditions and mask-like contours as input. The tool then analyses simulated images and predicts defect printability. It automatically calculates maximum CD variation and decides which defects are severe to affect patterns on wafer. In this paper, we assess the printability of defects for the mask of advanced technology nodes. In particular, we will compare the recovered mask contours with contours extracted from SEM image of the mask and compare simulation results with AIMSTM for a variety of defects and patterns. The results of printability assessment and the accuracy of comparison are presented in this paper. We also suggest how this method can be extended to predict printability of defects identified on EUV photomasks.

  10. Antineoplastic Efficacy of Novel Polyamine Analogues in Human Breast Cancer

    DTIC Science & Technology

    2005-06-01

    Davidson, N.E., and Casero, R.A.. Spermine oxidase SMO(PAOh1), not N1-acetylpolyamine oxidase (PAO) is the primary source of cytotoxic H2O2 in polyamine... spermine oxidase (PAOh1/SMO) mRNA and activity by a polyamine analogue in human breast cancer cell lines. The fourth Era of Hope meeting for the...SMO/PAOh1 Spermine Oxidase DFMO α-difluoromethylornithine BENSpm N1, N11-bis(ethyl)norspermine CHEMSpm N1-(cycloheptylmethyl)-N11-ethyl- 4,8

  11. High-Energy Radiation from a Model of Quasars, Active Galactic Nuclei, and the Galactic Center with Magnetic Monopoles

    NASA Astrophysics Data System (ADS)

    Peng, Qiu-he; Chou, Chih-kang

    2001-04-01

    The fact that magnetic monopoles may catalyze nucleon decay (the Rubakov-Callan [RC] effect) as predicated by the grand unified theory of particle physics is invoked as the energy source of quasars and active galactic nuclei. Recent study of this model revealed that the radius of the supermassive object (SMO) located at the Galactic center is much larger than its Schwarzschild radius. We propose that this SMOs could be the source of high-energy gamma-ray radiation, although the emitted radiation may be mainly concentrated in the infrared. The surface temperature of the SMO at the Galactic center is taken as 121 K, inferred from the observed maximum of the flux spectrum of Sgr A* at the near infrared (1×1013 Hz); the radius of the SMO is about 8.1×1015 cm or 1.1×104RS (RS is the Schwarzschild radius). The mass of the SMO is derived from the observed total luminosity of Sgr A* (1×1037 ergs s-1) as 2.5×106 Msolar. Strong gamma-ray radiation with energy higher than 0.5 MeV may be emitted from the SMO. The flux of positrons emitted from the SMO is estimated to be 6.5×1042e+ s-1. The content parameter of magnetic monopoles ξ≡[(Nm/NB)/1.9×10- 25](<σβ>/10-27) also may be deduced from observations to be 230. Taking the cross section of the RC effect as 1×10-27 cm2, the strength of the radial magnetic field at the surface of the SMO is estimated to be 20-100 G. Our model also can predict the production of extreme ultra-high-energy cosmic rays.

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

    McMillan, Kyle; Marleau, Peter; Brubaker, Erik

    In coded aperture imaging, one of the most important factors determining the quality of reconstructed images is the choice of mask/aperture pattern. In many applications, uniformly redundant arrays (URAs) are widely accepted as the optimal mask pattern. Under ideal conditions, thin and highly opaque masks, URA patterns are mathematically constructed to provide artifact-free reconstruction however, the number of URAs for a chosen number of mask elements is limited and when highly penetrating particles such as fast neutrons and high-energy gamma-rays are being imaged, the optimum is seldom achieved. In this case more robust mask patterns that provide better reconstructed imagemore » quality may exist. Through the use of heuristic optimization methods and maximum likelihood expectation maximization (MLEM) image reconstruction, we show that for both point and extended neutron sources a random mask pattern can be optimized to provide better image quality than that of a URA.« less

  13. Spectral Estimation Model Construction of Heavy Metals in Mining Reclamation Areas

    PubMed Central

    Dong, Jihong; Dai, Wenting; Xu, Jiren; Li, Songnian

    2016-01-01

    The study reported here examined, as the research subject, surface soils in the Liuxin mining area of Xuzhou, and explored the heavy metal content and spectral data by establishing quantitative models with Multivariable Linear Regression (MLR), Generalized Regression Neural Network (GRNN) and Sequential Minimal Optimization for Support Vector Machine (SMO-SVM) methods. The study results are as follows: (1) the estimations of the spectral inversion models established based on MLR, GRNN and SMO-SVM are satisfactory, and the MLR model provides the worst estimation, with R2 of more than 0.46. This result suggests that the stress sensitive bands of heavy metal pollution contain enough effective spectral information; (2) the GRNN model can simulate the data from small samples more effectively than the MLR model, and the R2 between the contents of the five heavy metals estimated by the GRNN model and the measured values are approximately 0.7; (3) the stability and accuracy of the spectral estimation using the SMO-SVM model are obviously better than that of the GRNN and MLR models. Among all five types of heavy metals, the estimation for cadmium (Cd) is the best when using the SMO-SVM model, and its R2 value reaches 0.8628; (4) using the optimal model to invert the Cd content in wheat that are planted on mine reclamation soil, the R2 and RMSE between the measured and the estimated values are 0.6683 and 0.0489, respectively. This result suggests that the method using the SMO-SVM model to estimate the contents of heavy metals in wheat samples is feasible. PMID:27367708

  14. Spectral Estimation Model Construction of Heavy Metals in Mining Reclamation Areas.

    PubMed

    Dong, Jihong; Dai, Wenting; Xu, Jiren; Li, Songnian

    2016-06-28

    The study reported here examined, as the research subject, surface soils in the Liuxin mining area of Xuzhou, and explored the heavy metal content and spectral data by establishing quantitative models with Multivariable Linear Regression (MLR), Generalized Regression Neural Network (GRNN) and Sequential Minimal Optimization for Support Vector Machine (SMO-SVM) methods. The study results are as follows: (1) the estimations of the spectral inversion models established based on MLR, GRNN and SMO-SVM are satisfactory, and the MLR model provides the worst estimation, with R² of more than 0.46. This result suggests that the stress sensitive bands of heavy metal pollution contain enough effective spectral information; (2) the GRNN model can simulate the data from small samples more effectively than the MLR model, and the R² between the contents of the five heavy metals estimated by the GRNN model and the measured values are approximately 0.7; (3) the stability and accuracy of the spectral estimation using the SMO-SVM model are obviously better than that of the GRNN and MLR models. Among all five types of heavy metals, the estimation for cadmium (Cd) is the best when using the SMO-SVM model, and its R² value reaches 0.8628; (4) using the optimal model to invert the Cd content in wheat that are planted on mine reclamation soil, the R² and RMSE between the measured and the estimated values are 0.6683 and 0.0489, respectively. This result suggests that the method using the SMO-SVM model to estimate the contents of heavy metals in wheat samples is feasible.

  15. Design intent optimization at the beyond 7nm node: the intersection of DTCO and EUVL stochastic mitigation techniques

    NASA Astrophysics Data System (ADS)

    Crouse, Michael; Liebmann, Lars; Plachecki, Vince; Salama, Mohamed; Chen, Yulu; Saulnier, Nicole; Dunn, Derren; Matthew, Itty; Hsu, Stephen; Gronlund, Keith; Goodwin, Francis

    2017-03-01

    The initial readiness of EUV patterning was demonstrated in 2016 with IBM Alliance's 7nm device technology. The focus has now shifted to driving the 'effective' k1 factor and enabling the second generation of EUV patterning. Thus, Design Technology Co-optimization (DTCO) has become a critical part of technology enablement as scaling has become more challenging and the industry pushes the limits of EUV lithography. The working partnership between the design teams and the process development teams typically involves an iterative approach to evaluate the manufacturability of proposed designs, subsequent modifications to those designs and finally a design manual for the technology. While this approach has served the industry well for many generations, the challenges at the Beyond 7nm node require a more efficient approach. In this work, we describe the use of "Design Intent" lithographic layout optimization where we remove the iterative component of DTCO and replace it with an optimization that achieves both a "patterning friendly" design and minimizes the well-known EUV stochastic effects. Solved together, this "design intent" approach can more quickly achieve superior lithographic results while still meeting the original device's functional specifications. Specifically, in this work we will demonstrate "design intent" optimization for critical BEOL layers using design tolerance bands to guide the source mask co-optimization. The design tolerance bands can be either supplied as part of the original design or derived from some basic rules. Additionally, the EUV stochastic behavior is mitigated by enhancing the image log slope (ILS) for specific key features as part of the overall optimization. We will show the benefit of the "design intent approach" on both bidirectional and unidirectional 28nm min pitch standard logic layouts and compare the more typical iterative SMO approach. Thus demonstrating the benefit of allowing the design to float within the specified range. Lastly, we discuss how the evolution of this approach could lead to layout optimization based entirely on some minimal set of functional requirements and process constraints.

  16. Design and pitch scaling for affordable node transition and EUV insertion scenario

    NASA Astrophysics Data System (ADS)

    Kim, Ryoung-han; Ryckaert, Julien; Raghavan, Praveen; Sherazi, Yasser; Debacker, Peter; Trivkovic, Darko; Gillijns, Werner; Tan, Ling Ee; Drissi, Youssef; Blanco, Victor; Bekaert, Joost; Mao, Ming; Larivière, Stephane; McIntyre, Greg

    2017-04-01

    imec's DTCO and EUV achievement toward imec 7nm (iN7) technology node which is industry 5nm node equivalent is reported with a focus on cost and scaling. Patterning-aware design methodology supports both iArF multiple patterning and EUV under one compliant design rule. FinFET device with contacted poly pitch of 42nm and metal pitch of 32nm with 7.5-track, 6.5-track, and 6-track standard cell library are explored. Scaling boosters are used to provide additional scaling and die cost benefit while lessening pitch shrink burden, and it makes EUV insertion more affordable. EUV pattern fidelity is optimized through OPC, SMO, M3D, mask sizing and SRAF. Processed wafers were characterized and edge-placement-error (EPE) variability is validated for EUV insertion. Scale-ability and cost of ownership of EUV patterning in aligned with iN7 standard cell design, integration and patterning specification are discussed.

  17. Working set selection using functional gain for LS-SVM.

    PubMed

    Bo, Liefeng; Jiao, Licheng; Wang, Ling

    2007-09-01

    The efficiency of sequential minimal optimization (SMO) depends strongly on the working set selection. This letter shows how the improvement of SMO in each iteration, named the functional gain (FG), is used to select the working set for least squares support vector machine (LS-SVM). We prove the convergence of the proposed method and give some theoretical support for its performance. Empirical comparisons demonstrate that our method is superior to the maximum violating pair (MVP) working set selection.

  18. Dry etching technologies for reflective multilayer

    NASA Astrophysics Data System (ADS)

    Iino, Yoshinori; Karyu, Makoto; Ita, Hirotsugu; Kase, Yoshihisa; Yoshimori, Tomoaki; Muto, Makoto; Nonaka, Mikio; Iwami, Munenori

    2012-11-01

    We have developed a highly integrated methodology for patterning Extreme Ultraviolet (EUV) mask, which has been highlighted for the lithography technique at the 14nm half-pitch generation and beyond. The EUV mask is characterized as a reflective-type mask which is completely different compared with conventional transparent-type of photo mask. And it requires not only patterning of absorber layer without damaging the underlying multi reflective layers (40 Si/Mo layers) but also etching multi reflective layers. In this case, the dry etch process has generally faced technical challenges such as the difficulties in CD control, etch damage to quartz substrate and low selectivity to the mask resist. Shibaura Mechatronics ARESTM mask etch system and its optimized etch process has already achieved the maximal etch performance at patterning two-layered absorber. And in this study, our process technologies of multi reflective layers will be evaluated by means of optimal combination of process gases and our optimized plasma produced by certain source power and bias power. When our ARES™ is used for multilayer etching, the user can choose to etch the absorber layer at the same time or etch only the multilayer.

  19. Design Architecture of field-effect transistor with back gate electrode for biosensor application

    NASA Astrophysics Data System (ADS)

    Fathil, M. F. M.; Arshad, M. K. Md.; Hashim, U.; Ruslinda, A. R.; Gopinath, Subash C. B.; M. Nuzaihan M., N.; Ayub, R. M.; Adzhri, R.; Zaki, M.; Azman, A. H.

    2016-07-01

    This paper presents the preparation method of photolithography chrome mask design used in fabrication process of field-effect transistor with back gate biasing based biosensor. Initially, the chrome masks are designed by studying the process flow of the biosensor fabrication, followed by drawing of the actual chrome mask using the AutoCAD software. The overall width and length of the device is optimized at 16 mm and 16 mm, respectively. Fabrication processes of the biosensor required five chrome masks, which included source and drain formation mask, the back gate area formation mask, electrode formation mask, front gate area formation mask, and passivation area formation mask. The complete chrome masks design will be sent for chrome mask fabrication and for future use in biosensor fabrication.

  20. Power law-based local search in spider monkey optimisation for lower order system modelling

    NASA Astrophysics Data System (ADS)

    Sharma, Ajay; Sharma, Harish; Bhargava, Annapurna; Sharma, Nirmala

    2017-01-01

    The nature-inspired algorithms (NIAs) have shown efficiency to solve many complex real-world optimisation problems. The efficiency of NIAs is measured by their ability to find adequate results within a reasonable amount of time, rather than an ability to guarantee the optimal solution. This paper presents a solution for lower order system modelling using spider monkey optimisation (SMO) algorithm to obtain a better approximation for lower order systems and reflects almost original higher order system's characteristics. Further, a local search strategy, namely, power law-based local search is incorporated with SMO. The proposed strategy is named as power law-based local search in SMO (PLSMO). The efficiency, accuracy and reliability of the proposed algorithm is tested over 20 well-known benchmark functions. Then, the PLSMO algorithm is applied to solve the lower order system modelling problem.

  1. Sterol Methyl Oxidases Affect Embryo Development via Auxin-Associated Mechanisms.

    PubMed

    Zhang, Xia; Sun, Shuangli; Nie, Xiang; Boutté, Yohann; Grison, Magali; Li, Panpan; Kuang, Susu; Men, Shuzhen

    2016-05-01

    Sterols are essential molecules for multiple biological processes, including embryogenesis, cell elongation, and endocytosis. The plant sterol biosynthetic pathway is unique in the involvement of two distinct sterol 4α-methyl oxidase (SMO) families, SMO1 and SMO2, which contain three and two isoforms, respectively, and are involved in sequential removal of the two methyl groups at C-4. In this study, we characterized the biological functions of members of the SMO2 gene family. SMO2-1 was strongly expressed in most tissues during Arabidopsis (Arabidopsis thaliana) development, whereas SMO2-2 showed a more specific expression pattern. Although single smo2 mutants displayed no obvious phenotype, the smo2-1 smo2-2 double mutant was embryonic lethal, and the smo2-1 smo2-2/+ mutant was dwarf, whereas the smo2-1/+ smo2-2 mutant exhibited a moderate phenotype. The phenotypes of the smo2 mutants resembled those of auxin-defective mutants. Indeed, the expression of DR5rev:GFP, an auxin-responsive reporter, was reduced and abnormal in smo2-1 smo2-2 embryos. Furthermore, the expression and subcellular localization of the PIN1 auxin efflux facilitator also were altered. Consistent with these observations, either the exogenous application of auxin or endogenous auxin overproduction (YUCCA9 overexpression) partially rescued the smo2-1 smo2-2 embryonic lethality. Surprisingly, the dwarf phenotype of smo2-1 smo2-2/+ was completely rescued by YUCCA9 overexpression. Gas chromatography-mass spectrometry analysis revealed a substantial accumulation of 4α-methylsterols, substrates of SMO2, in smo2 heterozygous double mutants. Together, our data suggest that SMO2s are important for correct sterol composition and function partially through effects on auxin accumulation, auxin response, and PIN1 expression to regulate Arabidopsis embryogenesis and postembryonic development. © 2016 American Society of Plant Biologists. All Rights Reserved.

  2. Sterol Methyl Oxidases Affect Embryo Development via Auxin-Associated Mechanisms1

    PubMed Central

    Zhang, Xia; Sun, Shuangli; Nie, Xiang; Boutté, Yohann; Grison, Magali; Li, Panpan; Kuang, Susu

    2016-01-01

    Sterols are essential molecules for multiple biological processes, including embryogenesis, cell elongation, and endocytosis. The plant sterol biosynthetic pathway is unique in the involvement of two distinct sterol 4α-methyl oxidase (SMO) families, SMO1 and SMO2, which contain three and two isoforms, respectively, and are involved in sequential removal of the two methyl groups at C-4. In this study, we characterized the biological functions of members of the SMO2 gene family. SMO2-1 was strongly expressed in most tissues during Arabidopsis (Arabidopsis thaliana) development, whereas SMO2-2 showed a more specific expression pattern. Although single smo2 mutants displayed no obvious phenotype, the smo2-1 smo2-2 double mutant was embryonic lethal, and the smo2-1 smo2-2/+ mutant was dwarf, whereas the smo2-1/+ smo2-2 mutant exhibited a moderate phenotype. The phenotypes of the smo2 mutants resembled those of auxin-defective mutants. Indeed, the expression of DR5rev:GFP, an auxin-responsive reporter, was reduced and abnormal in smo2-1 smo2-2 embryos. Furthermore, the expression and subcellular localization of the PIN1 auxin efflux facilitator also were altered. Consistent with these observations, either the exogenous application of auxin or endogenous auxin overproduction (YUCCA9 overexpression) partially rescued the smo2-1 smo2-2 embryonic lethality. Surprisingly, the dwarf phenotype of smo2-1 smo2-2/+ was completely rescued by YUCCA9 overexpression. Gas chromatography-mass spectrometry analysis revealed a substantial accumulation of 4α-methylsterols, substrates of SMO2, in smo2 heterozygous double mutants. Together, our data suggest that SMO2s are important for correct sterol composition and function partially through effects on auxin accumulation, auxin response, and PIN1 expression to regulate Arabidopsis embryogenesis and postembryonic development. PMID:27006488

  3. Efficient three-dimensional resist profile-driven source mask optimization optical proximity correction based on Abbe-principal component analysis and Sylvester equation

    NASA Astrophysics Data System (ADS)

    Lin, Pei-Chun; Yu, Chun-Chang; Chen, Charlie Chung-Ping

    2015-01-01

    As one of the critical stages of a very large scale integration fabrication process, postexposure bake (PEB) plays a crucial role in determining the final three-dimensional (3-D) profiles and lessening the standing wave effects. However, the full 3-D chemically amplified resist simulation is not widely adopted during the postlayout optimization due to the long run-time and huge memory usage. An efficient simulation method is proposed to simulate the PEB while considering standing wave effects and resolution enhancement techniques, such as source mask optimization and subresolution assist features based on the Sylvester equation and Abbe-principal component analysis method. Simulation results show that our algorithm is 20× faster than the conventional Gaussian convolution method.

  4. Overlay improvement by exposure map based mask registration optimization

    NASA Astrophysics Data System (ADS)

    Shi, Irene; Guo, Eric; Chen, Ming; Lu, Max; Li, Gordon; Li, Rivan; Tian, Eric

    2015-03-01

    Along with the increased miniaturization of semiconductor electronic devices, the design rules of advanced semiconductor devices shrink dramatically. [1] One of the main challenges of lithography step is the layer-to-layer overlay control. Furthermore, DPT (Double Patterning Technology) has been adapted for the advanced technology node like 28nm and 14nm, corresponding overlay budget becomes even tighter. [2][3] After the in-die mask registration (pattern placement) measurement is introduced, with the model analysis of a KLA SOV (sources of variation) tool, it's observed that registration difference between masks is a significant error source of wafer layer-to-layer overlay at 28nm process. [4][5] Mask registration optimization would highly improve wafer overlay performance accordingly. It was reported that a laser based registration control (RegC) process could be applied after the pattern generation or after pellicle mounting and allowed fine tuning of the mask registration. [6] In this paper we propose a novel method of mask registration correction, which can be applied before mask writing based on mask exposure map, considering the factors of mask chip layout, writing sequence, and pattern density distribution. Our experiment data show if pattern density on the mask keeps at a low level, in-die mask registration residue error in 3sigma could be always under 5nm whatever blank type and related writer POSCOR (position correction) file was applied; it proves random error induced by material or equipment would occupy relatively fixed error budget as an error source of mask registration. On the real production, comparing the mask registration difference through critical production layers, it could be revealed that registration residue error of line space layers with higher pattern density is always much larger than the one of contact hole layers with lower pattern density. Additionally, the mask registration difference between layers with similar pattern density could also achieve under 5nm performance. We assume mask registration excluding random error is mostly induced by charge accumulation during mask writing, which may be calculated from surrounding exposed pattern density. Multi-loading test mask registration result shows that with x direction writing sequence, mask registration behavior in x direction is mainly related to sequence direction, but mask registration in y direction would be highly impacted by pattern density distribution map. It proves part of mask registration error is due to charge issue from nearby environment. If exposure sequence is chip by chip for normal multi chip layout case, mask registration of both x and y direction would be impacted analogously, which has also been proved by real data. Therefore, we try to set up a simple model to predict the mask registration error based on mask exposure map, and correct it with the given POSCOR (position correction) file for advanced mask writing if needed.

  5. The Smo/Smo model: hedgehog-induced medulloblastoma with 90% incidence and leptomeningeal spread.

    PubMed

    Hatton, Beryl A; Villavicencio, Elisabeth H; Tsuchiya, Karen D; Pritchard, Joel I; Ditzler, Sally; Pullar, Barbara; Hansen, Stacey; Knoblaugh, Sue E; Lee, Donghoon; Eberhart, Charles G; Hallahan, Andrew R; Olson, James M

    2008-03-15

    Toward the goal of generating a mouse medulloblastoma model with increased tumor incidence, we developed a homozygous version of our ND2:SmoA1 model. Medulloblastomas form in 94% of homozygous Smo/Smo mice by 2 months of age. Tumor formation is, thus, predictable by age, before the symptomatic appearance of larger lesions. This high incidence and early onset of tumors is ideal for preclinical studies because mice can be enrolled before symptom onset and with a greater latency period before late-stage disease. Smo/Smo tumors also display leptomeningeal dissemination of neoplastic cells to the brain and spine, which occurs in many human cases. Despite an extended proliferation of granule neuron precursors (GNP) in the postnatal external granular layer (EGL), the internal granular layer formed normally in Smo/Smo mice and tumor formation occurred only in localized foci on the superficial surface of the molecular layer. Thus, tumor formation is not simply the result of over proliferation of GNPs within the EGL. Moreover, Smo/Smo medulloblastomas were transplantable and serially passaged in vivo, demonstrating the aggressiveness of tumor cells and their transformation beyond a hyperplastic state. The Smo/Smo model is the first mouse medulloblastoma model to show leptomeningeal spread. The adherence to human pathology, high incidence, and early onset of tumors thus make Smo/Smo mice an efficient model for preclinical studies.

  6. Model-based assist feature insertion for sub-40nm memory device

    NASA Astrophysics Data System (ADS)

    Suh, Sungsoo; Lee, Suk-joo; Choi, Seong-woon; Lee, Sung-Woo; Park, Chan-hoon

    2009-04-01

    Many issues need to be resolved for a production-worthy model based assist feature insertion flow for single and double exposure patterning process to extend low k1 process at 193 nm immersion technology. Model based assist feature insertion is not trivial to implement either for single and double exposure patterning compared to rule based methods. As shown in Fig. 1, pixel based mask inversion technology in itself has difficulties in mask writing and inspection although it presents as one of key technology to extend single exposure for contact layer. Thus far, inversion technology is tried as a cooptimization of target mask to simultaneously generate optimized main and sub-resolution assists features for a desired process window. Alternatively, its technology can also be used to optimize for a target feature after an assist feature types are inserted in order to simplify the mask complexity. Simplification of inversion mask is one of major issue with applying inversion technology to device development even if a smaller mask feature can be fabricated since the mask writing time is also a major factor. As shown in Figure 2, mask writing time may be a limiting factor in determining whether or not an inversion solution is viable. It can be reasoned that increased number of shot counts relates to increase in margin for inversion methodology. On the other hand, there is a limit on how complex a mask can be in order to be production worthy. There is also source and mask co-optimization which influences the final mask patterns and assist feature sizes and positions for a given target. In this study, we will discuss assist feature insertion methods for sub 40-nm technology.

  7. Challenges of anamorphic high-NA lithography and mask making

    NASA Astrophysics Data System (ADS)

    Hsu, Stephen D.; Liu, Jingjing

    2017-06-01

    Chip makers are actively working on the adoption of 0.33 numerical aperture (NA) EUV scanners for the 7-nm and 5-nm nodes (B. Turko, S. L. Carson, A. Lio, T. Liang, M. Phillips, et al., in `Proc. SPIE9776, Extreme Ultraviolet (EUV) Lithography VII', vol. 977602 (2016) doi: 10.1117/12.2225014; A. Lio, in `Proc. SPIE9776, Extreme Ultraviolet (EUV) Lithography VII', vol. 97760V (2016) doi: 10.1117/12.2225017). In the meantime, leading foundries and integrated device manufacturers are starting to investigate patterning options beyond the 5-nm node (O. Wood, S. Raghunathan, P. Mangat, V. Philipsen, V. Luong, et al., in `Proc. SPIE. 9422, Extreme Ultraviolet (EUV) Lithography VI', vol. 94220I (2015) doi: 10.1117/12.2085022). To minimize the cost and process complexity of multiple patterning beyond the 5-nm node, EUV high-NA single-exposure patterning is a preferred method over EUV double patterning (O. Wood, S. Raghunathan, P. Mangat, V. Philipsen, V. Luong, et al., in `Proc. SPIE. 9422, Extreme Ultraviolet (EUV) Lithography VI', vol. 94220I (2015) doi: 10.1117/12.2085022; J. van Schoot, K. van Ingen Schenau, G. Bottiglieri, K. Troost, J. Zimmerman, et al., `Proc. SPIE. 9776, Extreme Ultraviolet (EUV) Lithography VII', vol. 97761I (2016) doi: 10.1117/12.2220150). The EUV high-NA scanner equipped with a projection lens of 0.55 NA is designed to support resolutions below 10 nm. The high-NA system is beneficial for enhancing resolution, minimizing mask proximity correction bias, improving normalized image log slope (NILS), and controlling CD uniformity (CDU). However, increasing NA from 0.33 to 0.55 reduces the depth of focus (DOF) significantly. Therefore, the source mask optimization (SMO) with sub-resolution assist features (SRAFs) are needed to increase DOF to meet the demanding full chip process control requirements (S. Hsu, R. Howell, J. Jia, H.-Y. Liu, K. Gronlund, et al., EUV `Proc. SPIE9048, Extreme Ultraviolet (EUV) Lithography VI', (2015) doi: 10.1117/12.2086074). To ensure no assist feature printing, the assist feature sizes need to be scaled with λ/NA. The extremely small SRAF width (below 25 nm on the reticle) is difficult to fabricate across the full reticle. In this paper, we introduce an innovative `attenuated SRAF' to improve SRAF manufacturability and still maintain the process window benefit. A new mask fabrication process is proposed to use existing mask-making capability to manufacture the attenuated SRAFs. The high-NA EUV system utilizes anamorphic reduction; 4× in the horizontal (slit) direction and 8× in the vertical (scanning) direction (J. van Schoot, K. van Ingen Schenau, G. Bottiglieri, K. Troost, J. Zimmerman, et al., `Proc. SPIE. 9776, Extreme Ultraviolet (EUV) Lithography VII', vol. 97761I (2016) doi: 10.1117/12.2220150; B. Kneer, S. Migura, W. Kaiser, J. T. Neumann, J. van Schoot, in `Proc. SPIE9422, Extreme Ultraviolet (EUV) Lithography VI', vol. 94221G (2015) doi: 10.1117/12.2175488). For an anamorphic system, the magnification has an angular dependency, and thus, familiar mask specifications such as mask error factor (MEF) need to be redefined. Similarly, mask-manufacturing rule check (MRC) needs to consider feature orientation.

  8. The Hedgehog processing pathway is required for NSCLC growth and survival

    PubMed Central

    Rodriguez-Blanco, Jezabel; Schilling, Neal S.; Tokhunts, Robert; Giambelli, Camilla; Long, Jun; Liang Fei, Dennis; Singh, Samer; Black, Kendall E.; Wang, Zhiqiang; Galimberti, Fabrizio; Bejarano, Pablo A.; Elliot, Sharon; Glassberg, Marilyn K.; Nguyen, Dao M.; Lockwood, William W.; Lam, Wan L.; Dmitrovsky, Ethan; Capobianco, Anthony J.; Robbins, David J.

    2013-01-01

    Considerable interest has been generated from the results of recent clinical trials using SMOOTHENED (SMO) antagonists to inhibit the growth of HEDGEHOG (HH) signaling dependent tumors. This interest is tempered by the discovery of SMO mutations mediating resistance, underscoring the rationale for developing therapeutic strategies that interrupt HH signaling at levels distinct from those inhibiting SMO function. Here, we demonstrate that HH dependent non-small cell lung carcinoma (NSCLC) growth is sensitive to blockade of the HH pathway upstream of SMO, at the level of HH ligand processing. Individually, the use of different lentivirally delivered shRNA constructs targeting two functionally distinct HH-processing proteins, SKINNY HEDGEHOG (SKN) or DISPATCHED-1 (DISP-1), in NSCLC cell lines produced similar decreases in cell proliferation and increased cell death. Further, providing either an exogenous source of processed HH or a SMO agonist reverses these effects. The attenuation of HH processing, by knocking down either of these gene products, also abrogated tumor growth in mouse xenografts. Finally, we extended these findings to primary clinical specimens, showing that SKN is frequently over-expressed in NSCLC and that higher DISP-1 expression is associated with an unfavorable clinical outcome. Our results show a critical role for HH processing in HH-dependent tumors, identifies two potential druggable targets in the HH pathway, and suggest that similar therapeutic strategies could be explored to treat patients harboring HH ligand dependent cancers. PMID:22733134

  9. Heterologous expression and characterization of mouse spermine oxidase.

    PubMed

    Cervelli, Manuela; Polticelli, Fabio; Federico, Rodolfo; Mariottini, Paolo

    2003-02-14

    Polyamine oxidases are key enzymes responsible of the polyamine interconversion metabolism in animal cells. Recently, a novel enzyme belonging to this class of enzymes has been characterized for its capability to oxidize preferentially spermine and designated as spermine oxidase. This is a flavin adenine dinucleotide-containing enzyme, and it has been expressed both in vitro and in vivo systems. The primary structure of mouse spermine oxidase (mSMO) was deduced from a cDNA clone (Image Clone 264769) recovered by a data base search utilizing the human counterpart of polyamine oxidases, PAOh1. The open reading frame predicts a 555-amino acid protein with a calculated M(r) of 61,852.30, which shows a 95.1% identity with PAOh1. To understand the biochemical properties of mSMO and its structure/function relationship, the mSMO cDNA has been subcloned and expressed in secreted and secreted-tagged forms into Escherichia coli BL21 DE3 cells. The recombinant enzyme shows an optimal pH value of 8.0 and is able to oxidize rapidly spermine to spermidine and 3-aminopropanal and fails to act upon spermidine and N(1)-acetylpolyamines. The purified recombinant-tagged form enzyme (M(r) approximately 68,000) has K(m) and k(cat) values of 90 microm and 4.5 s(-1), respectively, using spermine as substrate at pH 8.0. Molecular modeling of mSMO protein based on maize polyamine oxidase three-dimensional structure suggests that the general features of maize polyamine oxidase active site are conserved in mSMO.

  10. ℓ0 -based sparse hyperspectral unmixing using spectral information and a multi-objectives formulation

    NASA Astrophysics Data System (ADS)

    Xu, Xia; Shi, Zhenwei; Pan, Bin

    2018-07-01

    Sparse unmixing aims at recovering pure materials from hyperpspectral images and estimating their abundance fractions. Sparse unmixing is actually ℓ0 problem which is NP-h ard, and a relaxation is often used. In this paper, we attempt to deal with ℓ0 problem directly via a multi-objective based method, which is a non-convex manner. The characteristics of hyperspectral images are integrated into the proposed method, which leads to a new spectra and multi-objective based sparse unmixing method (SMoSU). In order to solve the ℓ0 norm optimization problem, the spectral library is encoded in a binary vector, and a bit-wise flipping strategy is used to generate new individuals in the evolution process. However, a multi-objective method usually produces a number of non-dominated solutions, while sparse unmixing requires a single solution. How to make the final decision for sparse unmixing is challenging. To handle this problem, we integrate the spectral characteristic of hyperspectral images into SMoSU. By considering the spectral correlation in hyperspectral data, we improve the Tchebycheff decomposition function in SMoSU via a new regularization item. This regularization item is able to enforce the individual divergence in the evolution process of SMoSU. In this way, the diversity and convergence of population is further balanced, which is beneficial to the concentration of individuals. In the experiments part, three synthetic datasets and one real-world data are used to analyse the effectiveness of SMoSU, and several state-of-art sparse unmixing algorithms are compared.

  11. Modeling of thermomechanical changes of extreme-ultraviolet mask and their dependence on absorber variation

    NASA Astrophysics Data System (ADS)

    Ban, Chung-Hyun; Park, Eun-Sang; Park, Jae-Hun; Oh, Hye-Keun

    2018-06-01

    Thermal and structural deformation of extreme-ultraviolet lithography (EUVL) masks during the exposure process may become important issues as these masks are subject to rigorous image placement and flatness requirements. The reflective masks used for EUVL absorb energy during exposure, and the temperature of the masks rises as a result. This can cause thermomechanical deformation that can reduce the pattern quality. The use of very thick low-thermal-expansion substrate materials (LTEMs) may reduce energy absorption, but they do not completely eliminate mask deformation. Therefore, it is necessary to predict and optimize the effects of energy transferred from the extreme-ultraviolet (EUV) light source and the resultant patterns of structured EUV masks with complex multilayers. Our study shows that heat accumulates in the masks as exposure progresses. It has been found that a higher absorber ratio (pattern density) applied to the patterning of EUV masks exacerbates the problem, especially in masks with more complex patterns.

  12. Advanced EUV mask and imaging modeling

    NASA Astrophysics Data System (ADS)

    Evanschitzky, Peter; Erdmann, Andreas

    2017-10-01

    The exploration and optimization of image formation in partially coherent EUV projection systems with complex source shapes requires flexible, accurate, and efficient simulation models. This paper reviews advanced mask diffraction and imaging models for the highly accurate and fast simulation of EUV lithography systems, addressing important aspects of the current technical developments. The simulation of light diffraction from the mask employs an extended rigorous coupled wave analysis (RCWA) approach, which is optimized for EUV applications. In order to be able to deal with current EUV simulation requirements, several additional models are included in the extended RCWA approach: a field decomposition and a field stitching technique enable the simulation of larger complex structured mask areas. An EUV multilayer defect model including a database approach makes the fast and fully rigorous defect simulation and defect repair simulation possible. A hybrid mask simulation approach combining real and ideal mask parts allows the detailed investigation of the origin of different mask 3-D effects. The image computation is done with a fully vectorial Abbe-based approach. Arbitrary illumination and polarization schemes and adapted rigorous mask simulations guarantee a high accuracy. A fully vectorial sampling-free description of the pupil with Zernikes and Jones pupils and an optimized representation of the diffraction spectrum enable the computation of high-resolution images with high accuracy and short simulation times. A new pellicle model supports the simulation of arbitrary membrane stacks, pellicle distortions, and particles/defects on top of the pellicle. Finally, an extension for highly accurate anamorphic imaging simulations is included. The application of the models is demonstrated by typical use cases.

  13. Ringfield lithographic camera

    DOEpatents

    Sweatt, W.C.

    1998-09-08

    A projection lithography camera is presented with a wide ringfield optimized so as to make efficient use of extreme ultraviolet radiation from a large area radiation source (e.g., D{sub source} {approx_equal} 0.5 mm). The camera comprises four aspheric mirrors optically arranged on a common axis of symmetry. The camera includes an aperture stop that is accessible through a plurality of partial aperture stops to synthesize the theoretical aperture stop. Radiation from a mask is focused to form a reduced image on a wafer, relative to the mask, by reflection from the four aspheric mirrors. 11 figs.

  14. Model-based virtual VSB mask writer verification for efficient mask error checking and optimization prior to MDP

    NASA Astrophysics Data System (ADS)

    Pack, Robert C.; Standiford, Keith; Lukanc, Todd; Ning, Guo Xiang; Verma, Piyush; Batarseh, Fadi; Chua, Gek Soon; Fujimura, Akira; Pang, Linyong

    2014-10-01

    A methodology is described wherein a calibrated model-based `Virtual' Variable Shaped Beam (VSB) mask writer process simulator is used to accurately verify complex Optical Proximity Correction (OPC) and Inverse Lithography Technology (ILT) mask designs prior to Mask Data Preparation (MDP) and mask fabrication. This type of verification addresses physical effects which occur in mask writing that may impact lithographic printing fidelity and variability. The work described here is motivated by requirements for extreme accuracy and control of variations for today's most demanding IC products. These extreme demands necessitate careful and detailed analysis of all potential sources of uncompensated error or variation and extreme control of these at each stage of the integrated OPC/ MDP/ Mask/ silicon lithography flow. The important potential sources of variation we focus on here originate on the basis of VSB mask writer physics and other errors inherent in the mask writing process. The deposited electron beam dose distribution may be examined in a manner similar to optical lithography aerial image analysis and image edge log-slope analysis. This approach enables one to catch, grade, and mitigate problems early and thus reduce the likelihood for costly long-loop iterations between OPC, MDP, and wafer fabrication flows. It moreover describes how to detect regions of a layout or mask where hotspots may occur or where the robustness to intrinsic variations may be improved by modification to the OPC, choice of mask technology, or by judicious design of VSB shots and dose assignment.

  15. Hazardous Traffic Event Detection Using Markov Blanket and Sequential Minimal Optimization (MB-SMO)

    PubMed Central

    Yan, Lixin; Zhang, Yishi; He, Yi; Gao, Song; Zhu, Dunyao; Ran, Bin; Wu, Qing

    2016-01-01

    The ability to identify hazardous traffic events is already considered as one of the most effective solutions for reducing the occurrence of crashes. Only certain particular hazardous traffic events have been studied in previous studies, which were mainly based on dedicated video stream data and GPS data. The objective of this study is twofold: (1) the Markov blanket (MB) algorithm is employed to extract the main factors associated with hazardous traffic events; (2) a model is developed to identify hazardous traffic event using driving characteristics, vehicle trajectory, and vehicle position data. Twenty-two licensed drivers were recruited to carry out a natural driving experiment in Wuhan, China, and multi-sensor information data were collected for different types of traffic events. The results indicated that a vehicle’s speed, the standard deviation of speed, the standard deviation of skin conductance, the standard deviation of brake pressure, turn signal, the acceleration of steering, the standard deviation of acceleration, and the acceleration in Z (G) have significant influences on hazardous traffic events. The sequential minimal optimization (SMO) algorithm was adopted to build the identification model, and the accuracy of prediction was higher than 86%. Moreover, compared with other detection algorithms, the MB-SMO algorithm was ranked best in terms of the prediction accuracy. The conclusions can provide reference evidence for the development of dangerous situation warning products and the design of intelligent vehicles. PMID:27420073

  16. Hazardous Traffic Event Detection Using Markov Blanket and Sequential Minimal Optimization (MB-SMO).

    PubMed

    Yan, Lixin; Zhang, Yishi; He, Yi; Gao, Song; Zhu, Dunyao; Ran, Bin; Wu, Qing

    2016-07-13

    The ability to identify hazardous traffic events is already considered as one of the most effective solutions for reducing the occurrence of crashes. Only certain particular hazardous traffic events have been studied in previous studies, which were mainly based on dedicated video stream data and GPS data. The objective of this study is twofold: (1) the Markov blanket (MB) algorithm is employed to extract the main factors associated with hazardous traffic events; (2) a model is developed to identify hazardous traffic event using driving characteristics, vehicle trajectory, and vehicle position data. Twenty-two licensed drivers were recruited to carry out a natural driving experiment in Wuhan, China, and multi-sensor information data were collected for different types of traffic events. The results indicated that a vehicle's speed, the standard deviation of speed, the standard deviation of skin conductance, the standard deviation of brake pressure, turn signal, the acceleration of steering, the standard deviation of acceleration, and the acceleration in Z (G) have significant influences on hazardous traffic events. The sequential minimal optimization (SMO) algorithm was adopted to build the identification model, and the accuracy of prediction was higher than 86%. Moreover, compared with other detection algorithms, the MB-SMO algorithm was ranked best in terms of the prediction accuracy. The conclusions can provide reference evidence for the development of dangerous situation warning products and the design of intelligent vehicles.

  17. A semantic web ontology for small molecules and their biological targets.

    PubMed

    Choi, Jooyoung; Davis, Melissa J; Newman, Andrew F; Ragan, Mark A

    2010-05-24

    A wide range of data on sequences, structures, pathways, and networks of genes and gene products is available for hypothesis testing and discovery in biological and biomedical research. However, data describing the physical, chemical, and biological properties of small molecules have not been well-integrated with these resources. Semantically rich representations of chemical data, combined with Semantic Web technologies, have the potential to enable the integration of small molecule and biomolecular data resources, expanding the scope and power of biomedical and pharmacological research. We employed the Semantic Web technologies Resource Description Framework (RDF) and Web Ontology Language (OWL) to generate a Small Molecule Ontology (SMO) that represents concepts and provides unique identifiers for biologically relevant properties of small molecules and their interactions with biomolecules, such as proteins. We instanced SMO using data from three public data sources, i.e., DrugBank, PubChem and UniProt, and converted to RDF triples. Evaluation of SMO by use of predetermined competency questions implemented as SPARQL queries demonstrated that data from chemical and biomolecular data sources were effectively represented and that useful knowledge can be extracted. These results illustrate the potential of Semantic Web technologies in chemical, biological, and pharmacological research and in drug discovery.

  18. Spermine oxidase (SMO) activity in breast tumor tissues and biochemical analysis of the anticancer spermine analogues BENSpm and CPENSpm.

    PubMed

    Cervelli, Manuela; Bellavia, Gabriella; Fratini, Emiliano; Amendola, Roberto; Polticelli, Fabio; Barba, Marco; Federico, Rodolfo; Signore, Fabrizio; Gucciardo, Giacomo; Grillo, Rosalba; Woster, Patrick M; Casero, Robert A; Mariottini, Paolo

    2010-10-14

    Polyamine metabolism has a critical role in cell death and proliferation representing a potential target for intervention in breast cancer (BC). This study investigates the expression of spermine oxidase (SMO) and its prognostic significance in BC. Biochemical analysis of Spm analogues BENSpm and CPENSpm, utilized in anticancer therapy, was also carried out to test their property in silico and in vitro on the recombinant SMO enzyme. BC tissue samples were analyzed for SMO transcript level and SMO activity. Student's t test was applied to evaluate the significance of the differences in value observed in T and NT samples. The structure modeling analysis of BENSpm and CPENSpm complexes formed with the SMO enzyme and their inhibitory activity, assayed by in vitro experiments, were examined. Both the expression level of SMO mRNA and SMO enzyme activity were significantly lower in BC samples compared to NT samples. The modeling of BENSpm and CPENSpm complexes formed with SMO and their inhibition properties showed that both were good inhibitors. This study shows that underexpression of SMO is a negative marker in BC. The SMO induction is a remarkable chemotherapeutical target. The BENSpm and CPENSpm are efficient SMO inhibitors. The inhibition properties shown by these analogues could explain their poor positive outcomes in Phases I and II of clinical trials.

  19. Spermine oxidase (SMO) activity in breast tumor tissues and biochemical analysis of the anticancer spermine analogues BENSpm and CPENSpm

    PubMed Central

    2010-01-01

    Background Polyamine metabolism has a critical role in cell death and proliferation representing a potential target for intervention in breast cancer (BC). This study investigates the expression of spermine oxidase (SMO) and its prognostic significance in BC. Biochemical analysis of Spm analogues BENSpm and CPENSpm, utilized in anticancer therapy, was also carried out to test their property in silico and in vitro on the recombinant SMO enzyme. Methods BC tissue samples were analyzed for SMO transcript level and SMO activity. Student's t test was applied to evaluate the significance of the differences in value observed in T and NT samples. The structure modeling analysis of BENSpm and CPENSpm complexes formed with the SMO enzyme and their inhibitory activity, assayed by in vitro experiments, were examined. Results Both the expression level of SMO mRNA and SMO enzyme activity were significantly lower in BC samples compared to NT samples. The modeling of BENSpm and CPENSpm complexes formed with SMO and their inhibition properties showed that both were good inhibitors. Conclusions This study shows that underexpression of SMO is a negative marker in BC. The SMO induction is a remarkable chemotherapeutical target. The BENSpm and CPENSpm are efficient SMO inhibitors. The inhibition properties shown by these analogues could explain their poor positive outcomes in Phases I and II of clinical trials. PMID:20946629

  20. CFS-SMO based classification of breast density using multiple texture models.

    PubMed

    Sharma, Vipul; Singh, Sukhwinder

    2014-06-01

    It is highly acknowledged in the medical profession that density of breast tissue is a major cause for the growth of breast cancer. Increased breast density was found to be linked with an increased risk of breast cancer growth, as high density makes it difficult for radiologists to see an abnormality which leads to false negative results. Therefore, there is need for the development of highly efficient techniques for breast tissue classification based on density. This paper presents a hybrid scheme for classification of fatty and dense mammograms using correlation-based feature selection (CFS) and sequential minimal optimization (SMO). In this work, texture analysis is done on a region of interest selected from the mammogram. Various texture models have been used to quantify the texture of parenchymal patterns of breast. To reduce the dimensionality and to identify the features which differentiate between breast tissue densities, CFS is used. Finally, classification is performed using SMO. The performance is evaluated using 322 images of mini-MIAS database. Highest accuracy of 96.46% is obtained for two-class problem (fatty and dense) using proposed approach. Performance of selected features by CFS is also evaluated by Naïve Bayes, Multilayer Perceptron, RBF Network, J48 and kNN classifier. The proposed CFS-SMO method outperforms all other classifiers giving a sensitivity of 100%. This makes it suitable to be taken as a second opinion in classifying breast tissue density.

  1. METABOLISM OF N-ALKYLATED SPERMINE ANALOGUES BY POLYAMINE AND SPERMINE OXIDASES

    PubMed Central

    Häkkinen, Merja R.; Hyvönen, Mervi T.; Auriola, Seppo; Casero, Robert A.; Vepsäläinen, Jouko; Khomutov, Alex R.; Alhonen, Leena; Keinänen, Tuomo A.

    2010-01-01

    SUMMARY N-alkylated polyamine analogues have potential as anticancer and antiparasitic drugs. However, their metabolism in the host has remained incompletely defined thus potentially limiting their utility. Here, we have studied the degradation of three different spermine analogues N,N′-bis-(3-ethylaminopropyl)butane-1,4-diamine (DESPM), N-(3-benzyl-aminopropyl)-N'-(3-ethylaminopropyl)butane-1,4-diamine (BnEtSPM) and N,N′-bis-(3-benzylaminopropyl)butane-1,4-diamine (DBSPM) and related mono-alkylated derivatives as substrates of recombinant human polyamine oxidase (APAO) and spermine oxidase (SMO). APAO and SMO metabolized DESPM to EtSPD (Km(APAO)=10μM, kcat(APAO)=1.1s−1 and Km(SMO)=28μM, kcat(SMO)=0.8s−1, respectively), metabolized BnEtSPM to EtSPD (Km(APAO)=0.9 μM, kcat(APAO)=1.1s−1 and Km(SMO)=51μM, kcat(SMO)=0.4s−1, respectively), and metabolized DBSPM to BnSPD (Km(APAO)=5.4μM, kcat(APAO)= 2.0s−1 and Km(SMO)=33μM, kcat(SMO)=0.3s−1, respectively). Interestingly, mono-alkylated spermine derivatives were metabolized by APAO and SMO to SPD (EtSPM Km(APAO)=16μM, kcat(APAO)=1.5s−1; Km(SMO)=25μM, kcat(SMO) =8.2s−1; BnSPM Km(APAO)=6.0μM, kcat(APAO)=2.8s−1; Km(SMO)=19μM, kcat(SMO)=0.8s−1, respectively). Surprisingly, E t S P D ( Km(APAO)=37μM, kcat(APAO)=0.1s−1; Km(SMO)=48μM, kcat(SMO)=0.05s−1) and BnSPD (Km(APAO)=2.5μM, kcat(APAO)=3.5s−1; Km(SMO)=60μM, kcat(SMO)=0.54s−1) were metabolized to SPD by both the oxidases. Furthermore, we studied the degradation of DESPM, BnEtSPM or DBSPM in the DU145 prostate carcinoma cell line. The same major metabolites EtSPD and/or BnSPD were detected both in the culture medium and intracellularly after 48 hours of culture. Moreover, EtSPM and BnSPM were detected from cell samples. Present data shows that inducible SMO parallel with APAO could play an important role in polyamine based drug action, i.e. degradation of parent drug and its metabolites, having significant impact on efficiency of these drugs, and hence for the development of novel N-alkylated polyamine analogues. PMID:20012116

  2. Electronic structure of SmO and SmO- via slow photoelectron velocity-map imaging spectroscopy and spin-orbit CASPT2 calculations

    NASA Astrophysics Data System (ADS)

    Weichman, Marissa L.; Vlaisavljevich, Bess; DeVine, Jessalyn A.; Shuman, Nicholas S.; Ard, Shaun G.; Shiozaki, Toru; Neumark, Daniel M.; Viggiano, Albert A.

    2017-12-01

    The chemi-ionization reaction of atomic samarium, Sm + O → SmO+ + e-, has been investigated by the Air Force Research Laboratory as a means to modify local electron density in the ionosphere for reduction of scintillation of high-frequency radio waves. Neutral SmO is a likely unwanted byproduct. The spectroscopy of SmO is of great interest to aid in interpretation of optical emission spectra recorded following atmospheric releases of Sm as part of the Metal Oxide Space Cloud (MOSC) observations. Here, we report a joint experimental and theoretical study of SmO using slow photoelectron velocity-map imaging spectroscopy of cryogenically cooled SmO- anions (cryo-SEVI) and high-level spin-orbit complete active space calculations with corrections from second order perturbation theory (CASPT2). With cryo-SEVI, we measure the electron affinity of SmO to be 1.0581(11) eV and report electronic and vibrational structure of low-lying electronic states of SmO in good agreement with theory and prior experimental work. We also obtain spectra of higher-lying excited states of SmO for direct comparison to the MOSC results.

  3. SmoXYB1C1Z of Mycobacterium sp. Strain NBB4: a Soluble Methane Monooxygenase (sMMO)-Like Enzyme, Active on C2 to C4 Alkanes and Alkenes

    PubMed Central

    Martin, Kiri E.; Ozsvar, Jazmin

    2014-01-01

    Monooxygenase (MO) enzymes initiate the aerobic oxidation of alkanes and alkenes in bacteria. A cluster of MO genes (smoXYB1C1Z) of thus-far-unknown function was found previously in the genomes of two Mycobacterium strains (NBB3 and NBB4) which grow on hydrocarbons. The predicted Smo enzymes have only moderate amino acid identity (30 to 60%) to their closest homologs, the soluble methane and butane MOs (sMMO and sBMO), and the smo gene cluster has a different organization from those of sMMO and sBMO. The smoXYB1C1Z genes of NBB4 were cloned into pMycoFos to make pSmo, which was transformed into Mycobacterium smegmatis mc2-155. Cells of mc2-155(pSmo) metabolized C2 to C4 alkanes, alkenes, and chlorinated hydrocarbons. The activities of mc2-155(pSmo) cells were 0.94, 0.57, 0.12, and 0.04 nmol/min/mg of protein with ethene, ethane, propane, and butane as substrates, respectively. The mc2-155(pSmo) cells made epoxides from ethene, propene, and 1-butene, confirming that Smo was an oxygenase. Epoxides were not produced from larger alkenes (1-octene and styrene). Vinyl chloride and 1,2-dichloroethane were biodegraded by cells expressing Smo, with production of inorganic chloride. This study shows that Smo is a functional oxygenase which is active against small hydrocarbons. M. smegmatis mc2-155(pSmo) provides a new model for studying sMMO-like monooxygenases. PMID:25015887

  4. Evaluation of Semi-supervised Learning for Classification of Protein Crystallization Imagery.

    PubMed

    Sigdel, Madhav; Dinç, İmren; Dinç, Semih; Sigdel, Madhu S; Pusey, Marc L; Aygün, Ramazan S

    2014-03-01

    In this paper, we investigate the performance of two wrapper methods for semi-supervised learning algorithms for classification of protein crystallization images with limited labeled images. Firstly, we evaluate the performance of semi-supervised approach using self-training with naïve Bayesian (NB) and sequential minimum optimization (SMO) as the base classifiers. The confidence values returned by these classifiers are used to select high confident predictions to be used for self-training. Secondly, we analyze the performance of Yet Another Two Stage Idea (YATSI) semi-supervised learning using NB, SMO, multilayer perceptron (MLP), J48 and random forest (RF) classifiers. These results are compared with the basic supervised learning using the same training sets. We perform our experiments on a dataset consisting of 2250 protein crystallization images for different proportions of training and test data. Our results indicate that NB and SMO using both self-training and YATSI semi-supervised approaches improve accuracies with respect to supervised learning. On the other hand, MLP, J48 and RF perform better using basic supervised learning. Overall, random forest classifier yields the best accuracy with supervised learning for our dataset.

  5. Ringfield lithographic camera

    DOEpatents

    Sweatt, William C.

    1998-01-01

    A projection lithography camera is presented with a wide ringfield optimized so as to make efficient use of extreme ultraviolet radiation from a large area radiation source (e.g., D.sub.source .apprxeq.0.5 mm). The camera comprises four aspheric mirrors optically arranged on a common axis of symmetry with an increased etendue for the camera system. The camera includes an aperture stop that is accessible through a plurality of partial aperture stops to synthesize the theoretical aperture stop. Radiation from a mask is focused to form a reduced image on a wafer, relative to the mask, by reflection from the four aspheric mirrors.

  6. Plant sterol biosynthesis: identification of two distinct families of sterol 4alpha-methyl oxidases.

    PubMed Central

    Darnet, Sylvain; Rahier, Alain

    2004-01-01

    In plants, the conversion of cycloartenol into functional phytosterols requires the removal of the two methyl groups at C-4 by an enzymic complex including a sterol 4alpha-methyl oxidase (SMO). We report the cloning of candidate genes for SMOs in Arabidopsis thaliana, belonging to two distinct families termed SMO1 and SMO2 and containing three and two isoforms respectively. SMO1 and SMO2 shared low sequence identity with each other and were orthologous to the ERG25 gene from Saccharomyces cerevisiae which encodes the SMO. The plant SMO amino acid sequences possess all the three histidine-rich motifs (HX3H, HX2HH and HX2HH), characteristic of the small family of membrane-bound non-haem iron oxygenases that are involved in lipid oxidation. To elucidate the precise functions of SMO1 and SMO2 gene families, we have reduced their expression by using a VIGS (virus-induced gene silencing) approach in Nicotiana benthamiana. SMO1 and SMO2 cDNA fragments were inserted into a viral vector and N. benthamiana inoculated with the viral transcripts. After silencing with SMO1, a substantial accumulation of 4,4-dimethyl-9beta,19-cyclopropylsterols (i.e. 24-methylenecycloartanol) was obtained, whereas qualitative and quantitative levels of 4alpha-methylsterols were not affected. In the case of silencing with SMO2, a large accumulation of 4alpha-methyl-Delta7-sterols (i.e. 24-ethylidenelophenol and 24-ethyllophenol) was found, with no change in the levels of 4,4-dimethylsterols. These clear and distinct biochemical phenotypes demonstrate that, in contrast with animals and fungi, in photosynthetic eukaryotes, these two novel families of cDNAs are coding two distinct types of C-4-methylsterol oxidases controlling the level of 4,4-dimethylsterol and 4alpha-methylsterol precursors respectively. PMID:14653780

  7. Structural basis for Smoothened receptor modulation and chemoresistance to anti-cancer drugs

    PubMed Central

    Wang, Chong; Wu, Huixian; Evron, Tama; Vardy, Eyal; Han, Gye Won; Huang, Xi-Ping; Hufeisen, Sandy J.; Mangano, Thomas J.; Urban, Dan J.; Katritch, Vsevolod; Cherezov, Vadim; Caron, Marc G.; Roth, Bryan L.; Stevens, Raymond C.

    2014-01-01

    The Smoothened receptor (SMO) mediates signal transduction in the hedgehog pathway, which is implicated in normal development and carcinogenesis. SMO antagonists can suppress the growth of some tumors; however, mutations at SMO have been found to abolish their anti-tumor effects, a phenomenon known as chemoresistance. Here we report three crystal structures of human SMO bound to the antagonists SANT1 and Anta XV, and the agonist, SAG1.5, at 2.6–2.8Å resolution. The long and narrow cavity in the transmembrane domain of SMO harbors multiple ligand binding sites, where SANT1 binds at a deeper site as compared with other ligands. Distinct interactions at D4736.55 elucidated the structural basis for the differential effects of chemoresistance mutations on SMO antagonists. The agonist SAG1.5 induces a conformational rearrangement of the binding pocket residues, which could contribute to SMO activation. Collectively, these studies reveal the structural basis for the modulation of SMO by small molecules. PMID:25008467

  8. PI(4)P Promotes Phosphorylation and Conformational Change of Smoothened through Interaction with Its C-terminal Tail

    PubMed Central

    Zhang, Jie; Li, Xiang-An; Evers, B. Mark; Zhu, Haining; Jia, Jianhang

    2016-01-01

    In Hedgehog (Hh) signaling, binding of Hh to the Patched-Interference Hh (Ptc-Ihog) receptor complex relieves Ptc inhibition on Smoothened (Smo). A longstanding question is how Ptc inhibits Smo and how such inhibition is relieved by Hh stimulation. In this study, we found that Hh elevates production of phosphatidylinositol 4-phosphate (PI(4)P). Increased levels of PI(4)P promote, whereas decreased levels of PI(4)P inhibit, Hh signaling activity. We further found that PI(4)P directly binds Smo through an arginine motif, which then triggers Smo phosphorylation and activation. Moreover, we identified the pleckstrin homology (PH) domain of G protein-coupled receptor kinase 2 (Gprk2) as an essential component for enriching PI(4)P and facilitating Smo activation. PI(4)P also binds mouse Smo (mSmo) and promotes its phosphorylation and ciliary accumulation. Finally, Hh treatment increases the interaction between Smo and PI(4)P but decreases the interaction between Ptc and PI(4)P, indicating that, in addition to promoting PI(4)P production, Hh regulates the pool of PI(4)P associated with Ptc and Smo. PMID:26863604

  9. Library-based illumination synthesis for critical CMOS patterning.

    PubMed

    Yu, Jue-Chin; Yu, Peichen; Chao, Hsueh-Yung

    2013-07-01

    In optical microlithography, the illumination source for critical complementary metal-oxide-semiconductor layers needs to be determined in the early stage of a technology node with very limited design information, leading to simple binary shapes. Recently, the availability of freeform sources permits us to increase pattern fidelity and relax mask complexities with minimal insertion risks to the current manufacturing flow. However, source optimization across many patterns is often treated as a design-of-experiments problem, which may not fully exploit the benefits of a freeform source. In this paper, a rigorous source-optimization algorithm is presented via linear superposition of optimal sources for pre-selected patterns. We show that analytical solutions are made possible by using Hopkins formulation and quadratic programming. The algorithm allows synthesized illumination to be linked with assorted pattern libraries, which has a direct impact on design rule studies for early planning and design automation for full wafer optimization.

  10. Pharmacodynamic interactions of a solid formulation of sodium oxybate and ethanol in healthy volunteers

    PubMed Central

    Pross, Nathalie; Patat, Alain; Vivet, Philippe; Bidaut, Michelle; Fauchoux, Nicolas

    2015-01-01

    Aim The pharmacologic effects of sodium oxybate (SO) have a number of similarities with those of alcohol. This study evaluated the pharmacodynamic interaction of SMO.IR (a solid immediate release formulation of SO) and alcohol (0.7 (males) or 0.57 (females) g kg–1 alcohol using 40% vodka). Methods In a randomized, double-blind, double-dummy, crossover trial, 24 healthy volunteers received randomly a) 2.25 g SMO.IR and placebo alcohol preparation, b) 2.25 g f SMO.IR and alcohol, c) 2.25 g SMO.IR matching placebo and alcohol and d) 2.25 g of SMO.IR matching placebo and placebo alcohol preparation. Objective and subjective cognitive parameters, adverse events and vital signs were assessed before, 15 and 165 min after treatment administration. Results Alcohol produced the expected cognitive impairment and the expected subjective sedation rapidly after intake (from 15 min). The objective effects of SMO.IR were much less pronounced than those of alcohol. The reverse was observed for subjective complaints, which were related to lesser stimulation and greater sedation. Nevertheless, 165 min after administration this sedation feeling was less with SMO.IR than with alcohol. There was a significant interaction between SMO.IR and alcohol at 15 min (i.e. increase in alertness and stimulation and decrease in sedation). In addition, an isolated mild decrease in digit vigilance accuracy occurred at 165 min post-dose after the combination. The co-administration of SMO.IR and alcohol was safe and well-tolerated. Conclusion SMO.IR and alcohol have distinct adverse effect profiles. The objective effects of SMO.IR are much less marked than those of alcohol. No deleterious interaction was observed. PMID:25782469

  11. Validating high-resolution California coastal flood modeling with Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR)

    NASA Astrophysics Data System (ADS)

    O'Neill, A.

    2015-12-01

    The Coastal Storm Modeling System (CoSMoS) is a numerical modeling scheme used to predict coastal flooding due to sea level rise and storms influenced by climate change, currently in use in central California and in development for Southern California (Pt. Conception to the Mexican border). Using a framework of circulation, wave, analytical, and Bayesian models at different geographic scales, high-resolution results are translated as relevant hazards projections at the local scale that include flooding, wave heights, coastal erosion, shoreline change, and cliff failures. Ready access to accurate, high-resolution coastal flooding data is critical for further validation and refinement of CoSMoS and improved coastal hazard projections. High-resolution Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) provides an exceptional data source as appropriately-timed flights during extreme tides or storms provide a geographically-extensive method for determining areas of inundation and flooding extent along expanses of complex and varying coastline. Landward flood extents are numerically identified via edge-detection in imagery from single flights, and can also be ascertained via change detection using additional flights and imagery collected during average wave/tide conditions. The extracted flooding positions are compared against CoSMoS results for similar tide, water level, and storm-intensity conditions, allowing for robust testing and validation of CoSMoS and providing essential feedback for supporting regional and local model improvement.

  12. Use of simulation to optimize the pinhole diameter and mask thickness for an x-ray backscatter imaging system

    NASA Astrophysics Data System (ADS)

    Vella, A.; Munoz, Andre; Healy, Matthew J. F.; Lane, David; Lockley, D.

    2017-08-01

    The PENELOPE Monte Carlo simulation code was used to determine the optimum thickness and aperture diameter of a pinhole mask for X-ray backscatter imaging in a security application. The mask material needs to be thick enough to absorb most X-rays, and the pinhole must be wide enough for sufficient field of view whilst narrow enough for sufficient image spatial resolution. The model consisted of a fixed geometry test object, various masks with and without pinholes, and a 1040 x 1340 pixels' area detector inside a lead lined camera housing. The photon energy distribution incident upon masks was flat up to selected energy limits. This artificial source was used to avoid the optimisation being specific to any particular X-ray source technology. The pixelated detector was modelled by digitising the surface area represented by the PENELOPE phase space file and integrating the energies of the photons impacting within each pixel; a MATLAB code was written for this. The image contrast, signal to background ratio, spatial resolution, and collimation effect were calculated at the simulated detector as a function of pinhole diameter and various thicknesses of mask made of tungsten, tungsten/epoxy composite or bismuth alloy. A process of elimination was applied to identify suitable masks for a viable X-ray backscattering security application.

  13. Evaluation of Semi-supervised Learning for Classification of Protein Crystallization Imagery

    PubMed Central

    Sigdel, Madhav; Dinç, İmren; Dinç, Semih; Sigdel, Madhu S.; Pusey, Marc L.; Aygün, Ramazan S.

    2015-01-01

    In this paper, we investigate the performance of two wrapper methods for semi-supervised learning algorithms for classification of protein crystallization images with limited labeled images. Firstly, we evaluate the performance of semi-supervised approach using self-training with naïve Bayesian (NB) and sequential minimum optimization (SMO) as the base classifiers. The confidence values returned by these classifiers are used to select high confident predictions to be used for self-training. Secondly, we analyze the performance of Yet Another Two Stage Idea (YATSI) semi-supervised learning using NB, SMO, multilayer perceptron (MLP), J48 and random forest (RF) classifiers. These results are compared with the basic supervised learning using the same training sets. We perform our experiments on a dataset consisting of 2250 protein crystallization images for different proportions of training and test data. Our results indicate that NB and SMO using both self-training and YATSI semi-supervised approaches improve accuracies with respect to supervised learning. On the other hand, MLP, J48 and RF perform better using basic supervised learning. Overall, random forest classifier yields the best accuracy with supervised learning for our dataset. PMID:25914518

  14. Design of a Multistep Phase Mask for High-Energy Terahertz Pulse Generation by Optical Rectification

    NASA Astrophysics Data System (ADS)

    Avetisyan, Y.; Makaryan, A.; Tadevosyan, V.; Tonouchi, M.

    2017-12-01

    A new scheme for generating high-energy terahertz (THz) pulses based on using a multistep phase mask (MSPM) is suggested and analyzed. The mask is placed on the entrance surface of the nonlinear optical (NLO) crystal eliminating the necessity of the imaging optics. In contrast to the contact grating method, introduction of large amounts of angular dispersion is avoided. The operation principle of the suggested scheme is based on the fact that the MSPM splits a single input beam into many smaller time-delayed "beamlets," which together form a discretely tilted-front laser pulse in NLO crystal. The analysis of THz-pulse generation in ZnTe and lithium niobate (LN) crystals shows that application of ZnTe crystal is more preferable, especially when long-wavelength pump sources are used. The dimensions of the mask's steps required for high-energy THz-pulse generation in ZnTe and LN crystals are calculated. The optimal number of steps is estimated, taking into account individual beamlet's spatial broadening and problems related to the mask fabrication. The proposed method is a promising way to develop high-energy, monolithic, and alignment-free THz-pulse sources.

  15. Discovery of novel hedgehog antagonists from cell-based screening: Isosteric modification of p38 bisamides as potent inhibitors of SMO.

    PubMed

    Yang, Bin; Hird, Alexander W; Russell, Daniel John; Fauber, Benjamin P; Dakin, Les A; Zheng, Xiaolan; Su, Qibin; Godin, Robert; Brassil, Patrick; Devereaux, Erik; Janetka, James W

    2012-07-15

    Cell-based subset screening of compounds using a Gli transcription factor reporter cell assay and shh stimulated cell differentiation assay identified a series of bisamide compounds as hedgehog pathway inhibitors with good potency. Using a ligand-based optimization strategy, heteroaryl groups were utilized as conformationally restricted amide isosteres replacing one of the amides which significantly increased their potency against SMO and the hedgehog pathway while decreasing activity against p38α kinase. We report herein the identification of advanced lead compounds such as imidazole 11c and 11f encompassing good p38α selectivity, low nanomolar potency in both cell assays, excellent physiochemical properties and in vivo pharmacokinetics. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Patterning optimization for 55nm design rule DRAM/flash memory using production-ready customized illuminations

    NASA Astrophysics Data System (ADS)

    Chen, Ting; Van Den Broeke, Doug; Hsu, Stephen; Hsu, Michael; Park, Sangbong; Berger, Gabriel; Coskun, Tamer; de Vocht, Joep; Chen, Fung; Socha, Robert; Park, JungChul; Gronlund, Keith

    2005-11-01

    Illumination optimization, often combined with optical proximity corrections (OPC) to the mask, is becoming one of the critical components for a production-worthy lithography process for 55nm-node DRAM/Flash memory devices and beyond. At low-k1, e.g. k1<0.31, both resolution and imaging contrast can be severely limited by the current imaging tools while using the standard illumination sources. Illumination optimization is a process where the source shape is varied, in both profile and intensity distribution, to achieve enhancement in the final image contrast as compared to using the non-optimized sources. The optimization can be done efficiently for repetitive patterns such as DRAM/Flash memory cores. However, illumination optimization often produces source shapes that are "free-form" like and they can be too complex to be directly applicable for production and lack the necessary radial and annular symmetries desirable for the diffractive optical element (DOE) based illumination systems in today's leading lithography tools. As a result, post-optimization rendering and verification of the optimized source shape are often necessary to meet the production-ready or manufacturability requirements and ensure optimal performance gains. In this work, we describe our approach to the illumination optimization for k1<0.31 DRAM/Flash memory patterns, using an ASML XT:1400i at NA 0.93, where the all necessary manufacturability requirements are fully accounted for during the optimization. The imaging contrast in the resist is optimized in a reduced solution space constrained by the manufacturability requirements, which include minimum distance between poles, minimum opening pole angles, minimum ring width and minimum source filling factor in the sigma space. For additional performance gains, the intensity within the optimized source can vary in a gray-tone fashion (eight shades used in this work). Although this new optimization approach can sometimes produce closely spaced solutions as gauged by the NILS based metrics, we show that the optimal and production-ready source shape solution can be easily determined by comparing the best solutions to the "free-form" solution and more importantly, by their respective imaging fidelity and process latitude ranking. Imaging fidelity and process latitude simulations are performed to analyze the impact and sensitivity of the manufacturability requirements on pattern specific illumination optimizations using ASML XT:1400i and other latest imaging systems. Mask model based OPC (MOPC) is applied and optimized sequentially to ensure that the CD uniformity requirements are met.

  17. Modeling high-efficiency extreme ultraviolet etched multilayer phase-shift masks

    NASA Astrophysics Data System (ADS)

    Sherwin, Stuart; Neureuther, Andrew; Naulleau, Patrick

    2017-10-01

    Achieving high-throughput extreme ultraviolet (EUV) patterning remains a major challenge due to low source power; phase-shift masks can help solve this challenge for dense features near the resolution limit by creating brighter images than traditional absorber masks when illuminated with the same source power. We explore applications of etched multilayer phase-shift masks for EUV lithography, both in the current-generation 0.33 NA and next-generation 0.55 NA systems. We derive analytic formulas for the thin-mask throughput gains, which are 2.42× for lines and spaces and 5.86× for contacts compared with an absorber mask with dipole and quadrupole illumination, respectively. Using rigorous finite-difference time-domain simulations, we quantify variations in these gains by pitch and orientation, finding 87% to 113% of the thin-mask value for lines and spaces and a 91% to 99% for contacts. We introduce an edge placement error metric, which accounts for CD errors, relative feature motion, and telecentricity errors, and use this metric both to optimize mask designs for individual features and to explore which features can be printed on the same mask. Furthermore, we find that although partial coherence shrinks the process window, at an achievable sigma of 0.2 we obtain a depth of focus of 340 nm and an exposure latitude of 39.2%, suggesting that partial coherence will not limit the feasibility of this technology. Finally, we show that many problems such as sensitivity to etch uniformity can be greatly mitigated using a central obscuration in the imaging pupil.

  18. Dielectric tunability of vertically aligned ferroelectric-metal oxide nanocomposite films controlled by out-of-plane misfit strain

    NASA Astrophysics Data System (ADS)

    Wu, Huaping; Ma, Xuefu; Zhang, Zheng; Zhu, Jun; Wang, Jie; Chai, Guozhong

    2016-04-01

    A nonlinear thermodynamic model based on the vertically aligned nanocomposite (VAN) thin films of ferroelectric-metal oxide system has been developed to investigate the physical properties of the epitaxial Ba0.6Sr0.4TiO3 (BST) films containing vertical Sm2O3 (SmO) nanopillar arrays on the SrTiO3 substrate. The phase diagrams of out-of-plane lattice mismatch vs. volume fraction of SmO are calculated by minimizing the total free energy. It is found that the phase transformation and dielectric response of BST-SmO VAN systems are extremely dependent on the in-plane misfit strain, the out-of-plane lattice mismatch, the volume fraction of SmO phase, and the external electric field applied to the nanocomposite films at room temperature. In particular, the BST-SmO VAN systems exhibit higher dielectric properties than pure BST films. Giant dielectric response and maximum tunability are obtained near the lattice mismatch where the phase transition occurs. Under the in-plane misfit strain of umf=0.3 % and the out-of-plane lattice mismatch of u3=0.002 , the dielectric tunability can be dramatically enhanced to 90% with the increase of SmO volume fraction, which is well consistent with previous experimental results. This work represents an approach to further understand the dependence of physical properties on the lattice mismatch (in-plane and out-of-plane) and volume fraction, and to manipulate or optimize functionalities in the nanocomposite oxide thin films.

  19. Hydrogen Gas Sensors Based on Semiconductor Oxide Nanostructures

    PubMed Central

    Gu, Haoshuang; Wang, Zhao; Hu, Yongming

    2012-01-01

    Recently, the hydrogen gas sensing properties of semiconductor oxide (SMO) nanostructures have been widely investigated. In this article, we provide a comprehensive review of the research progress in the last five years concerning hydrogen gas sensors based on SMO thin film and one-dimensional (1D) nanostructures. The hydrogen sensing mechanism of SMO nanostructures and some critical issues are discussed. Doping, noble metal-decoration, heterojunctions and size reduction have been investigated and proved to be effective methods for improving the sensing performance of SMO thin films and 1D nanostructures. The effect on the hydrogen response of SMO thin films and 1D nanostructures of grain boundary and crystal orientation, as well as the sensor architecture, including electrode size and nanojunctions have also been studied. Finally, we also discuss some challenges for the future applications of SMO nanostructured hydrogen sensors. PMID:22778599

  20. Constitutive Activation of Smoothened in the Renal Collecting Ducts Leads to Renal Hypoplasia, Hydronephrosis, and Hydroureter.

    PubMed

    Gupta, Deepak Prasad; Hwang, Jae-Won; Cho, Eui-Sic; Kim, Won; Song, Chang Ho; Chai, Ok Hee

    2017-01-01

    Sonic Hedgehog (Shh) signaling plays a major role in and is essential for regulation, patterning, and proliferation during renal development. Smoothened (Smo) plays a pivot role in transducing the Shh-glioma-associated oncogene Kruppel family member. However, the cellular and molecular mechanism underlying the role of sustained Smo activation in postnatal kidney development is still not clearly understood. Using a conditional knockin mouse model that expresses a constitutively activated form of Smo (SmoM2) upon Homeobox-B7-mediated recombination (Hoxb7-Cre), the effects of Shh signaling were determined in postnatal kidney development. SmoM2;Hoxb7-Cre mutant mice showed growth retardation with a reduction of body weight. Constitutive activation of Smo in the renal collecting ducts caused renal hypoplasia, hydronephrosis, and hydroureter. The parenchymal area and glomerular numbers were reduced, but the glomerular density was increased in SmoM2;Hoxb7-Cre mutant mice. The expression of Patched 1, the receptor of Shh and a downstream target gene of the Shh signaling pathway, was highly restricted and it was upregulated in the inner medullary collecting ducts of the kidney. The proliferative cells in the mesenchyme and collecting ducts were decreased in SmoM2;Hoxb7-Cre mutant mice. This study showed for the first time that sustained Smo inhibits postnatal kidney development by suppressing the proliferation of the mesenchyme and medullary collecting ducts in mice. © 2017 S. Karger AG, Basel.

  1. DYRK1B as therapeutic target in Hedgehog/GLI-dependent cancer cells with Smoothened inhibitor resistance

    PubMed Central

    Gruber, Wolfgang; Hutzinger, Martin; Elmer, Dominik Patrick; Parigger, Thomas; Sternberg, Christina; Cegielkowski, Lukasz; Zaja, Mirko; Leban, Johann; Michel, Susanne; Hamm, Svetlana; Vitt, Daniel; Aberger, Fritz

    2016-01-01

    A wide range of human malignancies displays aberrant activation of Hedgehog (HH)/GLI signaling, including cancers of the skin, brain, gastrointestinal tract and hematopoietic system. Targeting oncogenic HH/GLI signaling with small molecule inhibitors of the essential pathway effector Smoothened (SMO) has shown remarkable therapeutic effects in patients with advanced and metastatic basal cell carcinoma. However, acquired and de novo resistance to SMO inhibitors poses severe limitations to the use of SMO antagonists and urgently calls for the identification of novel targets and compounds. Here we report on the identification of the Dual-Specificity-Tyrosine-Phosphorylation-Regulated Kinase 1B (DYRK1B) as critical positive regulator of HH/GLI signaling downstream of SMO. Genetic and chemical inhibition of DYRK1B in human and mouse cancer cells resulted in marked repression of HH signaling and GLI1 expression, respectively. Importantly, DYRK1B inhibition profoundly impaired GLI1 expression in both SMO-inhibitor sensitive and resistant settings. We further introduce a novel small molecule DYRK1B inhibitor, DYRKi, with suitable pharmacologic properties to impair SMO-dependent and SMO-independent oncogenic GLI activity. The results support the use of DYRK1B antagonists for the treatment of HH/GLI-associated cancers where SMO inhibitors fail to demonstrate therapeutic efficacy. PMID:26784250

  2. Phase-field simulations of GaN growth by selective area epitaxy on complex mask geometries

    DOE PAGES

    Aagesen, Larry K.; Coltrin, Michael Elliott; Han, Jung; ...

    2015-05-15

    Three-dimensional phase-field simulations of GaN growth by selective area epitaxy were performed. Furthermore, this model includes a crystallographic-orientation-dependent deposition rate and arbitrarily complex mask geometries. The orientation-dependent deposition rate can be determined from experimental measurements of the relative growth rates of low-index crystallographic facets. Growth on various complex mask geometries was simulated on both c-plane and a-plane template layers. Agreement was observed between simulations and experiment, including complex phenomena occurring at the intersections between facets. The sources of the discrepancies between simulated and experimental morphologies were also investigated. We found that the model provides a route to optimize masks andmore » processing conditions during materials synthesis for solar cells, light-emitting diodes, and other electronic and opto-electronic applications.« less

  3. Inhibition of polyamine and spermine oxidases by polyamine analogues.

    PubMed

    Bianchi, Marzia; Polticelli, Fabio; Ascenzi, Paolo; Botta, Maurizio; Federico, Rodolfo; Mariottini, Paolo; Cona, Alessandra

    2006-03-01

    Polyamine oxidase (PAO) and spermine oxidase (SMO) are involved in the catabolism of polyamines--basic regulators of cell growth and proliferation. The discovery of selective inhibitors of PAO and SMO represents an important tool in studying the involvement of these enzymes in polyamine homeostasis and a starting point for the development of novel antineoplastic drugs. Here, a comparative study on murine PAO (mPAO) and SMO (mSMO) inhibition by the polyamine analogues 1,8-diaminooctane, 1,12-diaminododecane, N-prenylagmatine (G3), guazatine and N,N1-bis(2,3-butadienyl)-1,4-butanediamine (MDL72527) is reported. Interestingly, 1,12-Diaminododecane and G3 behave as specific inhibitors of mPAO, values of K(i) for mPAO inhibition being lower than those for mSMO inactivation by several orders of magnitude. The analysis of molecular models of mPAO and mSMO indicates a significant reduction of the hydrophobic pocket located in maize PAO (MPAO) at the wider catalytic tunnel opening. This observation provides a rationale to explain the lower affinity displayed by G3, guazatine and MDL72527 for mPAO and mSMO as compared to MPAO. The different behaviour displayed by 1,12-diaminododecane towards mPAO and mSMO reveals the occurrence of basic differences in the ligand binding mode of the two enzymes, the first enzyme interacting mainly with substrate secondary amino groups and the second one with substrate primary amino groups. Thus, the data reported here provide the basis for the development of novel and selective inhibitors able to discriminate between mammalian SMO and PAO activities.

  4. Propagation of resist heating mask error to wafer level

    NASA Astrophysics Data System (ADS)

    Babin, S. V.; Karklin, Linard

    2006-10-01

    As technology is approaching 45 nm and below the IC industry is experiencing a severe product yield hit due to rapidly shrinking process windows and unavoidable manufacturing process variations. Current EDA tools are unable by their nature to deliver optimized and process-centered designs that call for 'post design' localized layout optimization DFM tools. To evaluate the impact of different manufacturing process variations on final product it is important to trace and evaluate all errors through design to manufacturing flow. Photo mask is one of the critical parts of this flow, and special attention should be paid to photo mask manufacturing process and especially to mask tight CD control. Electron beam lithography (EBL) is a major technique which is used for fabrication of high-end photo masks. During the writing process, resist heating is one of the sources for mask CD variations. Electron energy is released in the mask body mainly as heat, leading to significant temperature fluctuations in local areas. The temperature fluctuations cause changes in resist sensitivity, which in turn leads to CD variations. These CD variations depend on mask writing speed, order of exposure, pattern density and its distribution. Recent measurements revealed up to 45 nm CD variation on the mask when using ZEP resist. The resist heating problem with CAR resists is significantly smaller compared to other types of resists. This is partially due to higher resist sensitivity and the lower exposure dose required. However, there is no data yet showing CD errors on the wafer induced by CAR resist heating on the mask. This effect can be amplified by high MEEF values and should be carefully evaluated at 45nm and below technology nodes where tight CD control is required. In this paper, we simulated CD variation on the mask due to resist heating; then a mask pattern with the heating error was transferred onto the wafer. So, a CD error on the wafer was evaluated subject to only one term of the mask error budget - the resist heating CD error. In simulation of exposure using a stepper, variable MEEF was considered.

  5. The intrahepatic signalling niche of hedgehog is defined by primary cilia positive cells during chronic liver injury.

    PubMed

    Grzelak, Candice Alexandra; Martelotto, Luciano Gastón; Sigglekow, Nicholas David; Patkunanathan, Bramilla; Ajami, Katerina; Calabro, Sarah Ruth; Dwyer, Benjamin James; Tirnitz-Parker, Janina Elke Eleonore; Watkins, D Neil; Warner, Fiona Jane; Shackel, Nicholas Adam; McCaughan, Geoffrey William

    2014-01-01

    In vertebrates, canonical Hedgehog (Hh) pathway activation requires Smoothened (SMO) translocation to the primary cilium (Pc), followed by a GLI-mediated transcriptional response. In addition, a similar gene regulation occurs in response to growth factors/cytokines, although independently of SMO signalling. The Hh pathway plays a critical role in liver fibrosis/regeneration, however, the mechanism of activation in chronic liver injury is poorly understood. This study aimed to characterise Hh pathway activation upon thioacetamide (TAA)-induced chronic liver injury in vivo by defining Hh-responsive cells, namely cells harbouring Pc and Pc-localised SMO. C57BL/6 mice (wild-type or Ptc1(+/-)) were TAA-treated. Liver injury and Hh ligand/pathway mRNA and protein expression were assessed in vivo. SMO/GLI manipulation and SMO-dependent/independent activation of GLI-mediated transcriptional response in Pc-positive (Pc(+)) cells were studied in vitro. In vivo, Hh activation was progressively induced following TAA. At the epithelial-mesenchymal interface, injured hepatocytes produced Hh ligands. Progenitors, myofibroblasts, leukocytes and hepatocytes were GLI2(+). Pc(+) cells increased following TAA, but only EpCAM(+)/GLI2(+) progenitors were Pc(+)/SMO(+). In vitro, SMO knockdown/hGli3-R overexpression reduced proliferation/viability in Pc(+) progenitors, whilst increased proliferation occurred with hGli1 overexpression. HGF induced GLI transcriptional activity independently of Pc/SMO. Ptc1(+/-) mice exhibited increased progenitor, myofibroblast and fibrosis responses. In chronic liver injury, Pc(+) progenitors receive Hh ligand signals and process it through Pc/SMO-dependent activation of GLI-mediated transcriptional response. Pc/SMO-independent GLI activation likely occurs in Pc(-)/GLI2(+) cells. Increased fibrosis in Hh gain-of-function mice likely occurs by primary progenitor expansion/proliferation and secondary fibrotic myofibroblast expansion, in close contact with progenitors. Copyright © 2013 European Association for the Study of the Liver. All rights reserved.

  6. Best Matching Protein Conformations and Docking Programs for a Virtual Screening Campaign Against SMO Receptor.

    PubMed

    Amendola, Giorgio; Di Maio, Danilo; La Pietra, Valeria; Cosconati, Sandro

    2016-09-01

    SMO receptor is one of the main components of the Hedgehog biochemical pathway. In the last decades compelling body of evidence demonstrated that this receptor is a pertinent target for the treatment of various types of solid tumors. Recently, the X-ray determination of the three-dimensional structure of SMO in complex with different antagonists opened up the way for the structure-based design of new antagonists for this receptor that could possibly overcome the limitations connected with the induction of acquired tumor resistance. Herein, taking advantage of three different docking software (namely Glide, PLANTS, and Vina) and of the available SMO structures we set up a retrospective virtual screening (VS) protocol. A database, made up by known SMO antagonists and compounds with no alleged activity against the receptor was created and screened against the different SMO structures. To evaluate the performance of the ranking in VS calculations different statistical metrics (EF, AUAC and BEDROC) were employed allowing to identify the best performing VS docking protocol. Results of these studies will serve as a platform for the application of structure-based VS against the pharmaceutically relevant SMO receptor. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

    Aagesen, Larry K.; Coltrin, Michael Elliott; Han, Jung

    Three-dimensional phase-field simulations of GaN growth by selective area epitaxy were performed. Furthermore, this model includes a crystallographic-orientation-dependent deposition rate and arbitrarily complex mask geometries. The orientation-dependent deposition rate can be determined from experimental measurements of the relative growth rates of low-index crystallographic facets. Growth on various complex mask geometries was simulated on both c-plane and a-plane template layers. Agreement was observed between simulations and experiment, including complex phenomena occurring at the intersections between facets. The sources of the discrepancies between simulated and experimental morphologies were also investigated. We found that the model provides a route to optimize masks andmore » processing conditions during materials synthesis for solar cells, light-emitting diodes, and other electronic and opto-electronic applications.« less

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

    Aagesen, Larry K.; Thornton, Katsuyo, E-mail: kthorn@umich.edu; Coltrin, Michael E.

    Three-dimensional phase-field simulations of GaN growth by selective area epitaxy were performed. The model includes a crystallographic-orientation-dependent deposition rate and arbitrarily complex mask geometries. The orientation-dependent deposition rate can be determined from experimental measurements of the relative growth rates of low-index crystallographic facets. Growth on various complex mask geometries was simulated on both c-plane and a-plane template layers. Agreement was observed between simulations and experiment, including complex phenomena occurring at the intersections between facets. The sources of the discrepancies between simulated and experimental morphologies were also investigated. The model provides a route to optimize masks and processing conditions during materialsmore » synthesis for solar cells, light-emitting diodes, and other electronic and opto-electronic applications.« less

  9. Induction of human spermine oxidase SMO(PAOh1) is regulated at the levels of new mRNA synthesis, mRNA stabilization and newly synthesized protein

    PubMed Central

    2004-01-01

    The oxidation of polyamines induced by antitumour polyamine analogues has been associated with tumour response to specific agents. The human spermine oxidase, SMO(PAOh1), is one enzyme that may play a direct role in the cellular response to the antitumour polyamine analogues. In the present study, the induction of SMO(PAOh1) enzyme activity by CPENSpm [N1-ethyl-N11-(cyclopropyl)methyl-4,8,diazaundecane] is demonstrated to be a result of newly synthesized mRNA and protein. Inhibition of new RNA synthesis by actinomycin D inhibits both the appearance of SMO(PAOh1) mRNA and enzyme activity. Similarly, inhibition of newly synthesized protein with cycloheximide prevents analogue-induced enzyme activity. Half-life determinations indicate that stabilization of SMO(PAOh1) protein does not play a significant role in analogue-induced activity. However, half-life experiments using actinomycin D indicate that CPENSpm treatment not only increases mRNA expression, but also leads to a significant increase in mRNA half-life (17.1 and 8.8 h for CPENSpm-treated cells and control respectively). Using reporter constructs encompassing the SMO(PAOh1) promoter region, a 30–90% increase in transcription is observed after exposure to CPENSpm. The present results are consistent with the hypothesis that analogue-induced expression of SMO(PAOh1) is a result of increased transcription and stabilization of SMO(PAOh1) mRNA, leading to increased protein production and enzyme activity. These data indicate that the major level of control of SMO(PAOh1) expression in response to polyamine analogues exposure is at the level of mRNA. PMID:15496143

  10. Spermine oxidase, a polyamine catabolic enzyme that links Helicobacter pylori CagA and gastric cancer risk

    PubMed Central

    Chaturvedi, Rupesh; de Sablet, Thibaut; Peek, Richard M.; Wilson, Keith T.

    2012-01-01

    We have recently reported that Helicobacter pylori strains expressing the virulence factor cytotoxin-associated gene A (CagA) stimulate increased levels of spermine oxidase (SMO) in gastric epithelial cells, while cagA– strains did not. SMO catabolizes the polyamine spermine and produces H2O2 that results in both apoptosis and DNA damage. Exogenous overexpression of CagA confirmed these findings, and knockdown or inhibition of SMO blocked CagA-mediated apoptosis and DNA damage. The strong association of SMO, apoptosis, and DNA damage was also demonstrated in humans infected with cagA+, but not cagA– strains. In infected gerbils and mice, DNA damage was CagA-dependent and only present in epithelial cells that expressed SMO. We also discovered SMOhigh gastric epithelial cells from infected animals with dysplasia that are resistant to apoptosis despite high levels of DNA damage. Inhibition of polyamine synthesis or SMO could abrogate the development of this cell population that may represent precursors for neoplastic transformation. PMID:22555547

  11. Subcellular Localization of Patched and Smoothened, the Receptors for Sonic Hedgehog Signaling, in the Hippocampal Neuron

    PubMed Central

    Petralia, Ronald S.; Schwartz, Catherine M.; Wang, Ya-Xian; Mattson, Mark P.; Yao, Pamela J.

    2011-01-01

    Cumulative evidence suggests that, aside from patterning the embryonic neural tube, Sonic hedgehog (Shh) signaling plays important roles in the mature nervous system. In this study, we investigate the expression and localization of the Shh signaling receptors, Patched (Ptch) and Smoothened (Smo), in the hippocampal neurons of young and mature rats. Reverse transcriptase-polymerase chain reaction and immunoblotting analyses show that the expression of Ptch and Smo remains at a moderate level in young postnatal and adult brains. By using immunofluorescence light microscopy and immunoelectron microscopy, we examine the spatial distribution of Ptch and Smo within the hippocampal neurons. In young developing neurons, Ptch and Smo are present in the processes and are clustered at their growth cones. In mature neurons, Ptch and Smo are concentrated in dendrites, spines, and postsynaptic sites. Synaptic Ptch and Smo often co-exist with unusual structures—synaptic spinules and autophagosomes. Our results reveal the anatomical organization of the Shh receptors within both the young and the mature hippocampal neurons. PMID:21618238

  12. Cryptotermes brevis (Isoptera: Kalotermitidae) in the Azores: Lessons After 2 yr of Monitoring in the Archipelago

    PubMed Central

    Borges, Paulo A. V.; Guerreiro, Orlando; Ferreira, Maria T.; Borges, Annabella; Ferreira, Filomena; Bicudo, Nuno; Nunes, Lina; Marcos, Rita S.; Arroz, Ana M.; Scheffrahn, Rudolf H.; Myles, Timothy G.

    2014-01-01

    Abstract The dispersal flights of West Indian drywood termite, Cryptotermes brevis (Walker) (Isoptera: Kalotermitidae) were surveyed in the major cities of Azores. The sampling device used to estimate termite density consisted of a yellow adhesive trap (size 45 by 24 cm), placed with an artificial or natural light source in a dark attic environment. In addition, data from two other projects were used to improve the knowledge about the geographical distribution of the species. The level of infestation in the two main Azorean towns differed, with high levels in the houses of Angra do Heroísmo, whereas in Ponta Delgada, there are fewer houses with high levels of infestation. The infestation in Ponta Delgada shows a pattern of spreading from the center outward to the city’s periphery, whereas in Angra do Heroísmo, there was a pattern of spreading outward from several foci. The heavy infestation observed in Angra do Heroísmo and the clear increase of infestation levels observed from 2010 to 2011 is a reason for concern and calls for an urgent application of an Integrated Pest Management (IPM) control strategy. PMID:25368085

  13. CoSMoS Unravels Mysteries of Transcription Initiation

    PubMed Central

    Gourse, Richard L.; Landick, Robert

    2013-01-01

    Using a fluorescence method called colocalization single-molecule spectroscopy (CoSMoS), Friedman and Gelles dissect the kinetics of transcription initiation at a bacterial promoter. Ultimately, CoSMoS could greatly aid the study of the effects of DNA sequence and transcription factors on both prokaryotic and eukaryotic promoters. PMID:22341438

  14. Pixel-based OPC optimization based on conjugate gradients.

    PubMed

    Ma, Xu; Arce, Gonzalo R

    2011-01-31

    Optical proximity correction (OPC) methods are resolution enhancement techniques (RET) used extensively in the semiconductor industry to improve the resolution and pattern fidelity of optical lithography. In pixel-based OPC (PBOPC), the mask is divided into small pixels, each of which is modified during the optimization process. Two critical issues in PBOPC are the required computational complexity of the optimization process, and the manufacturability of the optimized mask. Most current OPC optimization methods apply the steepest descent (SD) algorithm to improve image fidelity augmented by regularization penalties to reduce the complexity of the mask. Although simple to implement, the SD algorithm converges slowly. The existing regularization penalties, however, fall short in meeting the mask rule check (MRC) requirements often used in semiconductor manufacturing. This paper focuses on developing OPC optimization algorithms based on the conjugate gradient (CG) method which exhibits much faster convergence than the SD algorithm. The imaging formation process is represented by the Fourier series expansion model which approximates the partially coherent system as a sum of coherent systems. In order to obtain more desirable manufacturability properties of the mask pattern, a MRC penalty is proposed to enlarge the linear size of the sub-resolution assistant features (SRAFs), as well as the distances between the SRAFs and the main body of the mask. Finally, a projection method is developed to further reduce the complexity of the optimized mask pattern.

  15. Modeling OPC complexity for design for manufacturability

    NASA Astrophysics Data System (ADS)

    Gupta, Puneet; Kahng, Andrew B.; Muddu, Swamy; Nakagawa, Sam; Park, Chul-Hong

    2005-11-01

    Increasing design complexity in sub-90nm designs results in increased mask complexity and cost. Resolution enhancement techniques (RET) such as assist feature addition, phase shifting (attenuated PSM) and aggressive optical proximity correction (OPC) help in preserving feature fidelity in silicon but increase mask complexity and cost. Data volume increase with rise in mask complexity is becoming prohibitive for manufacturing. Mask cost is determined by mask write time and mask inspection time, which are directly related to the complexity of features printed on the mask. Aggressive RET increase complexity by adding assist features and by modifying existing features. Passing design intent to OPC has been identified as a solution for reducing mask complexity and cost in several recent works. The goal of design-aware OPC is to relax OPC tolerances of layout features to minimize mask cost, without sacrificing parametric yield. To convey optimal OPC tolerances for manufacturing, design optimization should drive OPC tolerance optimization using models of mask cost for devices and wires. Design optimization should be aware of impact of OPC correction levels on mask cost and performance of the design. This work introduces mask cost characterization (MCC) that quantifies OPC complexity, measured in terms of fracture count of the mask, for different OPC tolerances. MCC with different OPC tolerances is a critical step in linking design and manufacturing. In this paper, we present a MCC methodology that provides models of fracture count of standard cells and wire patterns for use in design optimization. MCC cannot be performed by designers as they do not have access to foundry OPC recipes and RET tools. To build a fracture count model, we perform OPC and fracturing on a limited set of standard cells and wire configurations with all tolerance combinations. Separately, we identify the characteristics of the layout that impact fracture count. Based on the fracture count (FC) data from OPC and mask data preparation runs, we build models of FC as function of OPC tolerances and layout parameters.

  16. Respiratory source control using surgical masks with nanofiber media.

    PubMed

    Skaria, Shaji D; Smaldone, Gerald C

    2014-07-01

    Potentially infected individuals ('source') are sometimes encouraged to use face masks to reduce exposure of their infectious aerosols to others ('receiver'). To improve compliance with Respiratory Source Control via face mask and therefore reduce receiver exposure, a mask should be comfortable and effective. We tested a novel face mask designed to improve breathability and filtration using nanofiber filtration. Using radiolabeled test aerosols and a calibrated exposure chamber simulating source to receiver interaction, facepiece function was measured with a life-like ventilated manikin model. Measurements included mask airflow resistance (pressure difference during breathing), filtration, (mask capture of exhaled radiolabeled test aerosols), and exposure (the transfer of 'infectious' aerosols from the 'source' to a 'receiver'). Polydisperse aerosols were measured at the source with a mass median aerodynamic diameter of 0.95 µm. Approximately 90% of the particles were <2.0 µm. Tested facepieces included nanofiber prototype surgical masks, conventional surgical masks, and for comparison, an N95-class filtering facepiece respirator (commonly known as an 'N95 respirator'). Airflow through and around conventional surgical face mask and nanofiber prototype face mask was visualized using Schlieren optical imaging. Airflow resistance [ΔP, cmH2O] across sealed surgical masks (means: 0.1865 and 0.1791 cmH2O) approached that of the N95 (mean: 0.2664 cmH2O). The airflow resistance across the nanofiber face mask whether sealed or not sealed (0.0504 and 0.0311 cmH2O) was significantly reduced in comparison. In addition, 'infected' source airflow filtration and receiver exposure levels for nanofiber face masks placed on the source were comparable to that achieved with N95 placed on the source; 98.98% versus 82.68% and 0.0194 versus 0.0557, respectively. Compared to deflection within and around the conventional face masks, Schlieren optical imaging demonstrated enhanced airflow through the nanofiber mask. Substituting nanofiber for conventional filter media significantly reduced face mask airflow resistance directing more airflow through the face mask resulting in enhanced filtration. Respiratory source control efficacy similar to that achieved through the use of an N95 respirator worn by the source and decreased airflow resistance using nanofiber masks may improve compliance and reduce receiver exposure. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  17. Changes in ankle joint motion after Supramalleolar osteotomy: a cadaveric model.

    PubMed

    Kim, Hak Jun; Yeo, Eui Dong; Rhyu, Im Joo; Lee, Soon-Hyuck; Lee, Yeon Soo; Lee, Young Koo

    2017-09-09

    Malalignment of the ankle joint has been found after trauma, by neurological disorders, genetic predisposition and other unidentified factors, and results in asymmetrical joint loading. For a medial open wedge supramalleolar osteotomy(SMO), there are some debates as to whether concurrent fibular osteotomy should be performed. We assessed the changes in motion of ankle joint and plantar pressure after supramalleolar osteotomy without fibular osteotomy. Ten lower leg specimens below the knee were prepared from fresh-frozen human cadavers. They were harvested from five males (10 ankles)whose average age was 70 years. We assessed the motion of ankle joint as well as plantar pressure for SS(supra-syndesmotic) SMO and IS(intra-syndesmotic) SMO. After the osteotomy, each specimen was subjected to axial compression from 20 N preload to 350 N representing half-body weight. For the measurement of the motion of ankle joint, the changes in gap and point, angles in ankle joint were measured. The plantar pressure were also recorded using TekScan sensors. The changes in the various gap, point, and angles movements on SS-SMO and IS-SMO showed no statistically significant differences between the two groups. Regarding the shift of plantar center of force (COF) were noted in the anterolateral direction, but not statistically significant. SS-SMO and IS-SMO with intact fibula showed similar biomechanical effect on the ankle joint. We propose that IS-SMO should be considered carefully for the treatment of osteoarthrosis when fibular osteotomy is not performed because lateral cortex fracture was less likely using the intrasyndesmosis plane because of soft tissue support.

  18. Subcellular localization of Patched and Smoothened, the receptors for Sonic hedgehog signaling, in the hippocampal neuron.

    PubMed

    Petralia, Ronald S; Schwartz, Catherine M; Wang, Ya-Xian; Mattson, Mark P; Yao, Pamela J

    2011-12-15

    Cumulative evidence suggests that, aside from patterning the embryonic neural tube, Sonic hedgehog (Shh) signaling plays important roles in the mature nervous system. In this study, we investigate the expression and localization of the Shh signaling receptors, Patched (Ptch) and Smoothened (Smo), in the hippocampal neurons of young and mature rats. Reverse transcriptase-polymerase chain reaction and immunoblotting analyses show that the expression of Ptch and Smo remains at a moderate level in young postnatal and adult brains. By using immunofluorescence light microscopy and immunoelectron microscopy, we examine the spatial distribution of Ptch and Smo within the hippocampal neurons. In young developing neurons, Ptch and Smo are present in the processes and are clustered at their growth cones. In mature neurons, Ptch and Smo are concentrated in dendrites, spines, and postsynaptic sites. Synaptic Ptch and Smo often co-exist with unusual structures-synaptic spinules and autophagosomes. Our results reveal the anatomical organization of the Shh receptors within both the young and the mature hippocampal neurons. Copyright © 2011 Wiley-Liss, Inc.

  19. Silybum marianum oil attenuates oxidative stress and ameliorates mitochondrial dysfunction in mice treated with D-galactose

    PubMed Central

    Zhu, Shu Yun; Dong, Ying; Tu, Jie; Zhou, Yue; Zhou, Xing Hua; Xu, Bin

    2014-01-01

    Background: Silybum marianum has been used as herbal medicine for the treatment of liver disease, liver cirrhosis, and to prevent liver cancer in Europe and Asia since ancient times. Silybum marianum oil (SMO), a by-product of silymarin production, is rich in essential fatty acids, phospholipids, sterols, and vitamin E. However, it has not been very good development and use. Objective: In the present study, we used olive oil as a control to investigate the antioxidant and anti-aging effect of SMO in D-galactose (D-gal)-induced aging mice. Materials and Methods: D-gal was injected intraperitoneally (500 mg/kg body weight daily) for 7 weeks while SMO was simultaneously administered orally. The triglycerides (TRIG) and cholesterol (CHOL) levels were estimated in the serum. Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), monoamine oxidase (MAO), malondialdehyde (MDA), caspase-3, and Bcl-2 were determined in the liver and brain. The activities of Na+-K+-adenosine triphosphatase (ATPase), Ca2+-Mg2+-ATPase, membrane potential (ΔΨm), and membrane fluidity of the liver mitochondrial were estimated. Results: SMO decreased levels of TRIG and CHOL in aging mice. SMO administration elevated the activities of SOD, GSH-Px, and T-AOC, which are suppressed by aging. The levels of MAO and MDA in the liver and brain were reduced by SMO administration in aging mice. Enzyme linked immunosorbent assay showed that SMO significantly decreased the concentration of caspase-3 and improved the activity of Bcl-2 in the liver and brain of aging mice. Furthermore, SMO significantly attenuated the D-gal induced liver mitochondrial dysfunction by improving the activities of Na+-K+-ATPase, Ca2+-Mg2+-ATPase, membrane potential (ΔΨm), and membrane fluidity. Conclusion: These results indicate that SMO effectively attenuated oxidative damage and improved apoptosis related factors as well as liver mitochondrial dysfunction in aging mice. PMID:24914315

  20. A tool for urban soundscape evaluation applying Support Vector Machines for developing a soundscape classification model.

    PubMed

    Torija, Antonio J; Ruiz, Diego P; Ramos-Ridao, Angel F

    2014-06-01

    To ensure appropriate soundscape management in urban environments, the urban-planning authorities need a range of tools that enable such a task to be performed. An essential step during the management of urban areas from a sound standpoint should be the evaluation of the soundscape in such an area. In this sense, it has been widely acknowledged that a subjective and acoustical categorization of a soundscape is the first step to evaluate it, providing a basis for designing or adapting it to match people's expectations as well. In this sense, this work proposes a model for automatic classification of urban soundscapes. This model is intended for the automatic classification of urban soundscapes based on underlying acoustical and perceptual criteria. Thus, this classification model is proposed to be used as a tool for a comprehensive urban soundscape evaluation. Because of the great complexity associated with the problem, two machine learning techniques, Support Vector Machines (SVM) and Support Vector Machines trained with Sequential Minimal Optimization (SMO), are implemented in developing model classification. The results indicate that the SMO model outperforms the SVM model in the specific task of soundscape classification. With the implementation of the SMO algorithm, the classification model achieves an outstanding performance (91.3% of instances correctly classified). © 2013 Elsevier B.V. All rights reserved.

  1. Respiratory source control using a surgical mask: An in vitro study.

    PubMed

    Patel, Rajeev B; Skaria, Shaji D; Mansour, Mohamed M; Smaldone, Gerald C

    2016-07-01

    Cough etiquette and respiratory hygiene are forms of source control encouraged to prevent the spread of respiratory infection. The use of surgical masks as a means of source control has not been quantified in terms of reducing exposure to others. We designed an in vitro model using various facepieces to assess their contribution to exposure reduction when worn at the infectious source (Source) relative to facepieces worn for primary (Receiver) protection, and the factors that contribute to each. In a chamber with various airflows, radiolabeled aerosols were exhaled via a ventilated soft-face manikin head using tidal breathing and cough (Source). Another manikin, containing a filter, quantified recipient exposure (Receiver). The natural fit surgical mask, fitted (SecureFit) surgical mask and an N95-class filtering facepiece respirator (commonly known as an "N95 respirator") with and without a Vaseline-seal were tested. With cough, source control (mask or respirator on Source) was statistically superior to mask or unsealed respirator protection on the Receiver (Receiver protection) in all environments. To equal source control during coughing, the N95 respirator must be Vaseline-sealed. During tidal breathing, source control was comparable or superior to mask or respirator protection on the Receiver. Source control via surgical masks may be an important adjunct defense against the spread of respiratory infections. The fit of the mask or respirator, in combination with the airflow patterns in a given setting, are significant contributors to source control efficacy. Future clinical trials should include a surgical mask source control arm to assess the contribution of source control in overall protection against airborne infection.

  2. Probing mammalian spermine oxidase enzyme-substrate complex through molecular modeling, site-directed mutagenesis and biochemical characterization.

    PubMed

    Tavladoraki, Paraskevi; Cervelli, Manuela; Antonangeli, Fabrizio; Minervini, Giovanni; Stano, Pasquale; Federico, Rodolfo; Mariottini, Paolo; Polticelli, Fabio

    2011-04-01

    Spermine oxidase (SMO) and acetylpolyamine oxidase (APAO) are FAD-dependent enzymes that are involved in the highly regulated pathways of polyamine biosynthesis and degradation. Polyamine content is strictly related to cell growth, and dysfunctions in polyamine metabolism have been linked with cancer. Specific inhibitors of SMO and APAO would allow analyzing the precise role of these enzymes in polyamine metabolism and related pathologies. However, none of the available polyamine oxidase inhibitors displays the desired characteristics of selective affinity and specificity. In addition, repeated efforts to obtain structural details at the atomic level on these two enzymes have all failed. In the present study, in an effort to better understand structure-function relationships, SMO enzyme-substrate complex has been probed through a combination of molecular modeling, site-directed mutagenesis and biochemical studies. Results obtained indicate that SMO binds spermine in a similar conformation as that observed in the yeast polyamine oxidase FMS1-spermine complex and demonstrate a major role for residues His82 and Lys367 in substrate binding and catalysis. In addition, the SMO enzyme-substrate complex highlights the presence of an active site pocket with highly polar characteristics, which may explain the different substrate specificity of SMO with respect to APAO and provide the basis for the design of specific inhibitors for SMO and APAO.

  3. Optimization technique of wavefront coding system based on ZEMAX externally compiled programs

    NASA Astrophysics Data System (ADS)

    Han, Libo; Dong, Liquan; Liu, Ming; Zhao, Yuejin; Liu, Xiaohua

    2016-10-01

    Wavefront coding technique as a means of athermalization applied to infrared imaging system, the design of phase plate is the key to system performance. This paper apply the externally compiled programs of ZEMAX to the optimization of phase mask in the normal optical design process, namely defining the evaluation function of wavefront coding system based on the consistency of modulation transfer function (MTF) and improving the speed of optimization by means of the introduction of the mathematical software. User write an external program which computes the evaluation function on account of the powerful computing feature of the mathematical software in order to find the optimal parameters of phase mask, and accelerate convergence through generic algorithm (GA), then use dynamic data exchange (DDE) interface between ZEMAX and mathematical software to realize high-speed data exchanging. The optimization of the rotational symmetric phase mask and the cubic phase mask have been completed by this method, the depth of focus increases nearly 3 times by inserting the rotational symmetric phase mask, while the other system with cubic phase mask can be increased to 10 times, the consistency of MTF decrease obviously, the maximum operating temperature of optimized system range between -40°-60°. Results show that this optimization method can be more convenient to define some unconventional optimization goals and fleetly to optimize optical system with special properties due to its externally compiled function and DDE, there will be greater significance for the optimization of unconventional optical system.

  4. CoSMoS unravels mysteries of transcription initiation.

    PubMed

    Gourse, Richard L; Landick, Robert

    2012-02-17

    Using a fluorescence method called colocalization single-molecule spectroscopy (CoSMoS), Friedman and Gelles dissect the kinetics of transcription initiation at a bacterial promoter. Ultimately, CoSMoS could greatly aid the study of the effects of DNA sequence and transcription factors on both prokaryotic and eukaryotic promoters. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Spermine oxidase is a regulator of macrophage host response to Helicobacter pylori: enhancement of antimicrobial nitric oxide generation by depletion of spermine.

    PubMed

    Chaturvedi, Rupesh; Asim, Mohammad; Barry, Daniel P; Frye, Jeanetta W; Casero, Robert A; Wilson, Keith T

    2014-03-01

    The gastric pathogen Helicobacter pylori causes peptic ulcer disease and gastric cancer. We have reported that in H. pylori-activated macrophages, nitric oxide (NO) derived from inducible NO synthase (iNOS) can kill the bacterium, iNOS protein expression is dependent on uptake of its substrate L-arginine (L-Arg), the polyamine spermine can inhibit iNOS translation by inhibiting L-Arg uptake, and inhibition of polyamine synthesis enhances NO-mediated bacterial killing. Because spermine oxidase (SMO), which back-converts spermine to spermidine, is induced in macrophages by H. pylori, we determined its role in iNOS-dependent host defense. SMO shRNA knockdown in RAW 264.7 murine macrophages resulted in a marked decrease in H. pylori-stimulated iNOS protein, but not mRNA expression, and a 90% reduction in NO levels; NO production was also inhibited in primary murine peritoneal macrophages with SMO knockdown. There was an increase in spermine levels after H. pylori stimulation that rapidly decreased, while SMO knockdown caused a greater increase in spermine that was sustained. With SMO knockdown, L-Arg uptake and killing of H. pylori by macrophages was prevented. The overexpression of SMO by transfection of an expression plasmid prevented the H. pylori-stimulated increase in spermine levels, and led to increased L-Arg uptake, iNOS protein expression and NO production, and H. pylori killing. In two human monocytic cell lines, U937 and THP-1, overexpression of SMO caused a significant enhancement of NO production with H. pylori stimulation. By depleting spermine, SMO can abrogate the inhibitory effect of polyamines on innate immune responses to H. pylori by enhancing antimicrobial NO production.

  6. Respiratory Source Control Using Surgical Masks With Nanofiber Media

    PubMed Central

    Skaria, Shaji D.; Smaldone, Gerald C.

    2014-01-01

    Background: Potentially infected individuals (‘source’) are sometimes encouraged to use face masks to reduce exposure of their infectious aerosols to others (‘receiver’). To improve compliance with Respiratory Source Control via face mask and therefore reduce receiver exposure, a mask should be comfortable and effective. We tested a novel face mask designed to improve breathability and filtration using nanofiber filtration. Methods: Using radiolabeled test aerosols and a calibrated exposure chamber simulating source to receiver interaction, facepiece function was measured with a life-like ventilated manikin model. Measurements included mask airflow resistance (pressure difference during breathing), filtration, (mask capture of exhaled radiolabeled test aerosols), and exposure (the transfer of ‘infectious’ aerosols from the ‘source’ to a ‘receiver’). Polydisperse aerosols were measured at the source with a mass median aerodynamic diameter of 0.95 µm. Approximately 90% of the particles were <2.0 µm. Tested facepieces included nanofiber prototype surgical masks, conventional surgical masks, and for comparison, an N95-class filtering facepiece respirator (commonly known as an ‘N95 respirator’). Airflow through and around conventional surgical face mask and nanofiber prototype face mask was visualized using Schlieren optical imaging. Results: Airflow resistance [ΔP, cmH2O] across sealed surgical masks (means: 0.1865 and 0.1791 cmH2O) approached that of the N95 (mean: 0.2664 cmH2O). The airflow resistance across the nanofiber face mask whether sealed or not sealed (0.0504 and 0.0311 cmH2O) was significantly reduced in comparison. In addition, ‘infected’ source airflow filtration and receiver exposure levels for nanofiber face masks placed on the source were comparable to that achieved with N95 placed on the source; 98.98% versus 82.68% and 0.0194 versus 0.0557, respectively. Compared to deflection within and around the conventional face masks, Schlieren optical imaging demonstrated enhanced airflow through the nanofiber mask. Conclusions: Substituting nanofiber for conventional filter media significantly reduced face mask airflow resistance directing more airflow through the face mask resulting in enhanced filtration. Respiratory source control efficacy similar to that achieved through the use of an N95 respirator worn by the source and decreased airflow resistance using nanofiber masks may improve compliance and reduce receiver exposure. PMID:24737728

  7. Respiratory source control using a surgical mask: An in vitro study

    PubMed Central

    Patel, Rajeev B.; Skaria, Shaji D.; Mansour, Mohamed M.; Smaldone, Gerald C.

    2016-01-01

    ABSTRACT Cough etiquette and respiratory hygiene are forms of source control encouraged to prevent the spread of respiratory infection. The use of surgical masks as a means of source control has not been quantified in terms of reducing exposure to others. We designed an in vitro model using various facepieces to assess their contribution to exposure reduction when worn at the infectious source (Source) relative to facepieces worn for primary (Receiver) protection, and the factors that contribute to each. In a chamber with various airflows, radiolabeled aerosols were exhaled via a ventilated soft-face manikin head using tidal breathing and cough (Source). Another manikin, containing a filter, quantified recipient exposure (Receiver). The natural fit surgical mask, fitted (SecureFit) surgical mask and an N95-class filtering facepiece respirator (commonly known as an “N95 respirator”) with and without a Vaseline-seal were tested. With cough, source control (mask or respirator on Source) was statistically superior to mask or unsealed respirator protection on the Receiver (Receiver protection) in all environments. To equal source control during coughing, the N95 respirator must be Vaseline-sealed. During tidal breathing, source control was comparable or superior to mask or respirator protection on the Receiver. Source control via surgical masks may be an important adjunct defense against the spread of respiratory infections. The fit of the mask or respirator, in combination with the airflow patterns in a given setting, are significant contributors to source control efficacy. Future clinical trials should include a surgical mask source control arm to assess the contribution of source control in overall protection against airborne infection. PMID:26225807

  8. Enabling laboratory EUV research with a compact exposure tool

    NASA Astrophysics Data System (ADS)

    Brose, Sascha; Danylyuk, Serhiy; Tempeler, Jenny; Kim, Hyun-su; Loosen, Peter; Juschkin, Larissa

    2016-03-01

    In this work we present the capabilities of the designed and realized extreme ultraviolet laboratory exposure tool (EUVLET) which has been developed at the RWTH-Aachen, Chair for the Technology of Optical Systems (TOS), in cooperation with the Fraunhofer Institute for Laser Technology (ILT) and Bruker ASC GmbH. Main purpose of this laboratory setup is the direct application in research facilities and companies with small batch production, where the fabrication of high resolution periodic arrays over large areas is required. The setup can also be utilized for resist characterization and evaluation of its pre- and post-exposure processing. The tool utilizes a partially coherent discharge produced plasma (DPP) source and minimizes the number of other critical components to a transmission grating, the photoresist coated wafer and the positioning system for wafer and grating and utilizes the Talbot lithography approach. To identify the limits of this approach first each component is analyzed and optimized separately and relations between these components are identified. The EUV source has been optimized to achieve the best values for spatial and temporal coherence. Phase-shifting and amplitude transmission gratings have been fabricated and exposed. Several commercially available electron beam resists and one EUV resist have been characterized by open frame exposures to determine their contrast under EUV radiation. Cold development procedure has been performed to further increase the resist contrast. By analyzing the exposure results it can be demonstrated that only a 1:1 copy of the mask structure can be fully resolved by the utilization of amplitude masks. The utilized phase-shift masks offer higher 1st order diffraction efficiency and allow a demagnification of the mask structure in the achromatic Talbot plane.

  9. Cryptotermes brevis (Isoptera: Kalotermitidae) in the Azores: lessons after 2 yr of monitoring in the Archipelago.

    PubMed

    Borges, Paulo A V; Guerreiro, Orlando; Ferreira, Maria T; Borges, Annabella; Ferreira, Filomena; Bicudo, Nuno; Nunes, Lina; Marcos, Rita S; Arroz, Ana M; Scheffrahn, Rudolf H; Myles, Timothy G

    2014-01-01

    The dispersal flights of West Indian drywood termite, Cryptotermes brevis (Walker) (Isoptera: Kalotermitidae) were surveyed in the major cities of Azores. The sampling device used to estimate termite density consisted of a yellow adhesive trap (size 45 by 24 cm), placed with an artificial or natural light source in a dark attic environment. In addition, data from two other projects were used to improve the knowledge about the geographical distribution of the species. The level of infestation in the two main Azorean towns differed, with high levels in the houses of Angra do Heroísmo, whereas in Ponta Delgada, there are fewer houses with high levels of infestation. The infestation in Ponta Delgada shows a pattern of spreading from the center outward to the city's periphery, whereas in Angra do Heroísmo, there was a pattern of spreading outward from several foci. The heavy infestation observed in Angra do Heroísmo and the clear increase of infestation levels observed from 2010 to 2011 is a reason for concern and calls for an urgent application of an Integrated Pest Management (IPM) control strategy. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

  10. Spatial release from masking based on binaural processing for up to six maskers

    PubMed Central

    Yost, William A.

    2017-01-01

    Spatial Release from Masking (SRM) was measured for identification of a female target word spoken in the presence of male masker words. Target words from a single loudspeaker located at midline were presented when two, four, or six masker words were presented either from the same source as the target or from spatially separated masker sources. All masker words were presented from loudspeakers located symmetrically around the centered target source in the front azimuth hemifield. Three masking conditions were employed: speech-in-speech masking (involving both informational and energetic masking), speech-in-noise masking (involving energetic masking), and filtered speech-in-filtered speech masking (involving informational masking). Psychophysical results were summarized as three-point psychometric functions relating proportion of correct word identification to target-to-masker ratio (in decibels) for both the co-located and spatially separated target and masker sources cases. SRM was then calculated by comparing the slopes and intercepts of these functions. SRM decreased as the number of symmetrically placed masker sources increased from two to six. This decrease was independent of the type of masking, with almost no SRM measured for six masker sources. These results suggest that when SRM is dependent primarily on binaural processing, SRM is effectively limited to fewer than six sound sources. PMID:28372135

  11. Precision process calibration and CD predictions for low-k1 lithography

    NASA Astrophysics Data System (ADS)

    Chen, Ting; Park, Sangbong; Berger, Gabriel; Coskun, Tamer H.; de Vocht, Joep; Chen, Fung; Yu, Linda; Hsu, Stephen; van den Broeke, Doug; Socha, Robert; Park, Jungchul; Gronlund, Keith; Davis, Todd; Plachecki, Vince; Harris, Tom; Hansen, Steve; Lambson, Chuck

    2005-06-01

    Leading resist calibration for sub-0.3 k1 lithography demands accuracy <2nm for CD through pitch. An accurately calibrated resist process is the prerequisite for establishing production-worthy manufacturing under extreme low k1. From an integrated imaging point of view, the following key components must be simultaneously considered during the calibration - high numerical aperture (NA>0.8) imaging characteristics, customized illuminations (measured vs. modeled pupil profiles), resolution enhancement technology (RET) mask with OPC, reticle metrology, and resist thin film substrate. For imaging at NA approaching unity, polarized illumination can impact significantly the contrast formation in the resist film stack, and therefore it is an important factor to consider in the CD-based resist calibration. For aggressive DRAM memory core designs at k1<0.3, pattern-specific illumination optimization has proven to be critical for achieving the required imaging performance. Various optimization techniques from source profile optimization with fixed mask design to the combined source and mask optimization have been considered for customer designs and available imaging capabilities. For successful low-k1 process development, verification of the optimization results can only be made with a sufficiently tunable resist model that can predicate the wafer printing accurately under various optimized process settings. We have developed, for resist patterning under aggressive low-k1 conditions, a novel 3D diffusion model equipped with double-Gaussian convolution in each dimension. Resist calibration with the new diffusion model has demonstrated a fitness and CD predication accuracy that rival or outperform the traditional 3D physical resist models. In this work, we describe our empirical approach to achieving the nm-scale precision for advanced lithography process calibrations, using either measured 1D CD through-pitch or 2D memory core patterns. We show that for ArF imaging, the current resist development and diffusion modeling can readily achieve ~1-2nm max CD errors for common 1D through-pitch and aggressive 2D memory core resist patterns. Sensitivities of the calibrated models to various process parameters are analyzed, including the comparison between the measured and modeled (Gaussian or GRAIL) pupil profiles. We also report our preliminary calibration results under selected polarized illumination conditions.

  12. A Synthesis Model of Sustainable Market Orientation: Conceptualization, Measurement, and Influence on Academic Accreditation--A Case Study of Egyptian-Accredited Faculties

    ERIC Educational Resources Information Center

    Abou-Warda, Sherein H.

    2014-01-01

    Higher education institutions are increasingly concerned about accreditation. Although sustainable market orientation (SMO) bears on academic accreditation, to date, no study has developed a valid scale of SMO or assessed its influence on accreditation. The purpose of this paper is to construct and validate an SMO scale that was developed in…

  13. Single-Molecule Analysis of Pre-mRNA Splicing with Colocalization Single-Molecule Spectroscopy (CoSMoS).

    PubMed

    Braun, Joerg E; Serebrov, Victor

    2017-01-01

    Recent development of single-molecule techniques to study pre-mRNA splicing has provided insights into the dynamic nature of the spliceosome. Colocalization single-molecule spectroscopy (CoSMoS) allows following spliceosome assembly in real time at single-molecule resolution in the full complexity of cellular extracts. A detailed protocol of CoSMoS has been published previously (Anderson and Hoskins, Methods Mol Biol 1126:217-241, 2014). Here, we provide an update on the technical advances since the first CoSMoS studies including slide surface treatment, data processing, and representation. We describe various labeling strategies to generate RNA reporters with multiple dyes (or other moieties) at specific locations.

  14. ILP-based co-optimization of cut mask layout, dummy fill, and timing for sub-14nm BEOL technology

    NASA Astrophysics Data System (ADS)

    Han, Kwangsoo; Kahng, Andrew B.; Lee, Hyein; Wang, Lutong

    2015-10-01

    Self-aligned multiple patterning (SAMP), due to its low overlay error, has emerged as the leading option for 1D gridded back-end-of-line (BEOL) in sub-14nm nodes. To form actual routing patterns from a uniform "sea of wires", a cut mask is needed for line-end cutting or realization of space between routing segments. Constraints on cut shapes and minimum cut spacing result in end-of-line (EOL) extensions and non-functional (i.e. dummy fill) patterns; the resulting capacitance and timing changes must be consistent with signoff performance analyses and their impacts should be minimized. In this work, we address the co-optimization of cut mask layout, dummy fill, and design timing for sub-14nm BEOL design. Our central contribution is an optimizer based on integer linear programming (ILP) to minimize the timing impact due to EOL extensions, considering (i) minimum cut spacing arising in sub-14nm nodes; (ii) cut assignment to different cut masks (color assignment); and (iii) the eligibility to merge two unit-size cuts into a bigger cut. We also propose a heuristic approach to remove dummy fills after the ILP-based optimization by extending the usage of cut masks. Our heuristic can improve critical path performance under minimum metal density and mask density constraints. In our experiments, we study the impact of number of cut masks, minimum cut spacing and metal density under various constraints. Our studies of optimized cut mask solutions in these varying contexts give new insight into the tradeoff of performance and cost that is afforded by cut mask patterning technology options.

  15. Methanol Adsorption and Reaction on Samaria Thin Films on Pt(111).

    PubMed

    Jhang, Jin-Hao; Schaefer, Andreas; Zielasek, Volkmar; Weaver, Jason F; Bäumer, Marcus

    2015-09-17

    We investigated the adsorption and reaction of methanol on continuous and discontinuous films of samarium oxide (SmO x ) grown on Pt(111) in ultrahigh vacuum. The methanol decomposition was studied by temperature programmed desorption (TPD) and infrared reflection absorption spectroscopy (IRRAS), while structural changes of the oxide surface were monitored by low-energy electron diffraction (LEED). Methanol dehydrogenates to adsorbed methoxy species on both the continuous and discontinuous SmO x films, eventually leading to the desorption of CO and H₂ which desorbs at temperatures in the range 400-600 K. Small quantities of CO₂ are also detected mainly on as-prepared Sm₂O₃ thin films, but the production of CO₂ is limited during repeated TPD runs. The discontinuous film exhibits the highest reactivity compared to the continuous film and the Pt(111) substrate. The reactivity of methanol on reduced and reoxidized films was also investigated, revealing how SmO x structures influence the chemical behavior. Over repeated TPD experiments, a SmO x structural/chemical equilibrium condition is found which can be approached either from oxidized or reduced films. We also observed hydrogen absence in TPD which indicates that hydrogen is stored either in SmO x films or as OH groups on the SmO x surfaces.

  16. Effects of hard mask etch on final topography of advanced phase shift masks

    NASA Astrophysics Data System (ADS)

    Hortenbach, Olga; Rolff, Haiko; Lajn, Alexander; Baessler, Martin

    2017-07-01

    Continuous shrinking of the semiconductor device dimensions demands steady improvements of the lithographic resolution on wafer level. These requirements challenge the photomask industry to further improve the mask quality in all relevant printing characteristics. In this paper topography of the Phase Shift Masks (PSM) was investigated. Effects of hard mask etch on phase shift uniformity and mask absorber profile were studied. Design of experiments method (DoE) was used for the process optimization, whereas gas composition, bias power of the hard mask main etch and bias power of the over-etch were varied. In addition, influence of the over-etch time was examined at the end of the experiment. Absorber depth uniformity, sidewall angle (SWA), reactive ion etch lag (RIE lag) and through pitch (TP) dependence were analyzed. Measurements were performed by means of Atomic-force microscopy (AFM) using critical dimension (CD) mode with a boot-shaped tip. Scanning electron microscope (SEM) cross-section images were prepared to verify the profile quality. Finally CD analysis was performed to confirm the optimal etch conditions. Significant dependence of the absorber SWA on hard mask (HM) etch conditions was observed revealing an improvement potential for the mask absorber profile. It was found that hard mask etch can leave a depth footprint in the absorber layer. Thus, the etch depth uniformity of hard mask etch is crucial for achieving a uniform phase shift over the active mask area. The optimized hard mask etch process results in significantly improved mask topography without deterioration of tight CD specifications.

  17. Dissipation of sulfamethoxazole in pasture soils as affected by soil and environmental factors.

    PubMed

    Srinivasan, Prakash; Sarmah, Ajit K

    2014-05-01

    The dissipation of sulfamethoxazole (SMO) antibiotic in three different soils was investigated through laboratory incubation studies. The experiments were conducted under different incubation conditions such as initial chemical concentration, soil depth, temperature, and with sterilisation. The results indicate that SMO dissipated rapidly in New Zealand pasture soils, and the 50% dissipation times (DT50) in Hamilton, Te Kowhai and Horotiu soils under non-sterile conditions were 9.24, 4.3 and 13.33 days respectively. During the incubation period for each sampling event the soil dehydrogenase activity (DHA) and the variation in microbial community were monitored thorough phospholipid fatty acid extraction analysis (PLFA). The DHA data correlated well with the dissipation rate constants of SMO antibiotic, an increase in the DHA activity resulted in faster antibiotic dissipation. The PLFA analysis was indicative of higher bacterial presence as compared to fungal community, highlighting the type of microbial community responsible for dissipation. The results indicate that with increasing soil depth, SMO dissipation in soil was slower (except for Horotiu) while with increase in temperature the antibiotic loss was faster, and was noticeable in all the soils. Both the degree of biological activity and the temperature of the soil influenced overall SMO dissipation. SMO is not likely to persist more than 5-6 months in all three soils suggesting that natural biodegradation may be sufficient for the removal of these contaminants from the soil. Its dissipation in sterile soils indicated abiotic factors such as strong sorption onto soil components to play a role in the dissipation of SMO. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Digging a hole under Hedgehog: downstream inhibition as an emerging anticancer strategy.

    PubMed

    Di Magno, Laura; Coni, Sonia; Di Marcotullio, Lucia; Canettieri, Gianluca

    2015-08-01

    Hedgehog signaling is a key regulator of development and stem cell fate and its aberrant activation is a leading cause of a number of tumors. Activating germline or somatic mutations of genes encoding Hh pathway components are found in Basal Cell Carcinoma (BCC) and Medulloblastoma (MB). Ligand-dependent Hedgehog hyperactivation, due to autocrine or paracrine mechanisms, is also observed in a large number of malignancies of the breast, colon, skin, bladder, pancreas and other tissues. The key tumorigenic role of Hedgehog has prompted effort aimed at identifying inhibitors of this signaling. To date, only the antagonists of the membrane transducer Smo have been approved for therapy or are under clinical trials in patients with BCC and MB linked to Ptch or Smo mutations. Despite the good initial response, patients treated with Smo antagonists have eventually developed resistance due to the occurrence of compensating mechanisms. Furthermore, Smo antagonists are not effective in tumors where the Hedgehog hyperactivation is due to mutations of pathway components downstream of Smo, or in case of non-canonical, Smo-independent activation of the Gli transcription factors. For all these reasons, the research of Hh inhibitors acting downstream of Smo is becoming an area of intensive investigation. In this review we illustrate the progresses made in the identification of effective Hedgehog inhibitors and their application in cancer, with a special emphasis on the newly identified downstream inhibitors. We describe in detail the Gli inhibitors and illustrate their mode of action and applications in experimental and/or clinical settings. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Crystal structure of a multi-domain human smoothened receptor in complex with a super stabilizing ligand

    NASA Astrophysics Data System (ADS)

    Zhang, Xianjun; Zhao, Fei; Wu, Yiran; Yang, Jun; Han, Gye Won; Zhao, Suwen; Ishchenko, Andrii; Ye, Lintao; Lin, Xi; Ding, Kang; Dharmarajan, Venkatasubramanian; Griffin, Patrick R.; Gati, Cornelius; Nelson, Garrett; Hunter, Mark S.; Hanson, Michael A.; Cherezov, Vadim; Stevens, Raymond C.; Tan, Wenfu; Tao, Houchao; Xu, Fei

    2017-05-01

    The Smoothened receptor (SMO) belongs to the Class Frizzled of the G protein-coupled receptor (GPCR) superfamily, constituting a key component of the Hedgehog signalling pathway. Here we report the crystal structure of the multi-domain human SMO, bound and stabilized by a designed tool ligand TC114, using an X-ray free-electron laser source at 2.9 Å. The structure reveals a precise arrangement of three distinct domains: a seven-transmembrane helices domain (TMD), a hinge domain (HD) and an intact extracellular cysteine-rich domain (CRD). This architecture enables allosteric interactions between the domains that are important for ligand recognition and receptor activation. By combining the structural data, molecular dynamics simulation, and hydrogen-deuterium-exchange analysis, we demonstrate that transmembrane helix VI, extracellular loop 3 and the HD play a central role in transmitting the signal employing a unique GPCR activation mechanism, distinct from other multi-domain GPCRs.

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

    Zhang, Xianjun; Zhao, Fei; Wu, Yiran

    Here, the Smoothened receptor (SMO) belongs to the Class Frizzled of the G protein-coupled receptor (GPCR) superfamily, constituting a key component of the Hedgehog signalling pathway. Here we report the crystal structure of the multi-domain human SMO, bound and stabilized by a designed tool ligand TC114, using an X-ray free-electron laser source at 2.9 Å. The structure reveals a precise arrangement of three distinct domains: a seven-transmembrane helices domain (TMD), a hinge domain (HD) and an intact extracellular cysteine-rich domain (CRD). This architecture enables allosteric interactions between the domains that are important for ligand recognition and receptor activation. By combiningmore » the structural data, molecular dynamics simulation, and hydrogen-deuterium-exchange analysis, we demonstrate that transmembrane helix VI, extracellular loop 3 and the HD play a central role in transmitting the signal employing a unique GPCR activation mechanism, distinct from other multi-domain GPCRs.« less

  1. Utilization of a modified special-cubic design and an electronic tongue for bitterness masking formulation optimization.

    PubMed

    Li, Lianli; Naini, Venkatesh; Ahmed, Salah U

    2007-10-01

    A unique modification of simplex design was applied to an electronic tongue (E-Tongue) analysis in bitterness masking formulation optimization. Three formulation variables were evaluated in the simplex design, i.e. concentrations of two taste masking polymers, Amberlite and Carbopol, and pH of the granulating fluid. Response of the design was a bitterness distance measured using an E-Tongue by applying a principle component analysis, which represents taste masking efficiency of the formulation. The smaller the distance, the better the bitterness masking effect. Contour plots and polynomial equations of the bitterness distance response were generated as a function of formulation composition and pH. It was found that interactions between polymer and pH reduced the bitterness of the formulation, attributed to pH-dependent ionization and complexation properties of the ionic polymers, thus keeping the drug out of solution and unavailable to bitterness perception. At pH 4.9 and an Amberlite/Carbopol ratio of 1.4:1 (w/w), the optimal taste masking formulation was achieved and in agreement with human gustatory sensation study results. Therefore, adopting a modified simplex experimental design on response measured using an E-Tongue provided an efficient approach to taste masking formulation optimization using ionic binding polymers. (c) 2007 Wiley-Liss, Inc.

  2. Variability-aware double-patterning layout optimization for analog circuits

    NASA Astrophysics Data System (ADS)

    Li, Yongfu; Perez, Valerio; Tripathi, Vikas; Lee, Zhao Chuan; Tseng, I.-Lun; Ong, Jonathan Yoong Seang

    2018-03-01

    The semiconductor industry has adopted multi-patterning techniques to manage the delay in the extreme ultraviolet lithography technology. During the design process of double-patterning lithography layout masks, two polygons are assigned to different masks if their spacing is less than the minimum printable spacing. With these additional design constraints, it is very difficult to find experienced layout-design engineers who have a good understanding of the circuit to manually optimize the mask layers in order to minimize color-induced circuit variations. In this work, we investigate the impact of double-patterning lithography on analog circuits and provide quantitative analysis for our designers to select the optimal mask to minimize the circuit's mismatch. To overcome the problem and improve the turn-around time, we proposed our smart "anchoring" placement technique to optimize mask decomposition for analog circuits. We have developed a software prototype that is capable of providing anchoring markers in the layout, allowing industry standard tools to perform automated color decomposition process.

  3. The edge of awareness: Mask spatial density, but not color, determines optimal temporal frequency for continuous flash suppression.

    PubMed

    Drewes, Jan; Zhu, Weina; Melcher, David

    2018-01-01

    The study of how visual processing functions in the absence of visual awareness has become a major research interest in the vision-science community. One of the main sources of evidence that stimuli that do not reach conscious awareness-and are thus "invisible"-are still processed to some degree by the visual system comes from studies using continuous flash suppression (CFS). Why and how CFS works may provide more general insight into how stimuli access awareness. As spatial and temporal properties of stimuli are major determinants of visual perception, we hypothesized that these properties of the CFS masks would be of significant importance to the achieved suppression depth. In previous studies however, the spatial and temporal properties of the masks themselves have received little study, and masking parameters vary widely across studies, making a metacomparison difficult. To investigate the factors that determine the effectiveness of CFS, we varied both the temporal frequency and the spatial density of Mondrian-style masks. We consistently found the longest suppression duration for a mask temporal frequency of around 6 Hz. In trials using masks with reduced spatial density, suppression was weaker and frequency tuning was less precise. In contrast, removing color reduced mask effectiveness but did not change the pattern of suppression strength as a function of frequency. Overall, this pattern of results stresses the importance of CFS mask parameters and is consistent with the idea that CFS works by disrupting the spatiotemporal mechanisms that underlie conscious access to visual input.

  4. Combining malaria control with house electrification: adherence to recommended behaviours for proper deployment of solar-powered mosquito trapping systems, Rusinga Island, western Kenya.

    PubMed

    Oria, Prisca A; Alaii, Jane; Ayugi, Margaret; Takken, Willem; Leeuwis, Cees

    2015-08-01

    To investigate community adherence to recommended behaviours for proper deployment of solar-powered mosquito trapping systems (SMoTS) after 3- to 10-week use. Solar-powered mosquito trapping system, which also provided power for room lighting and charging mobile phones, were installed in houses in Rusinga Island, western Kenya. We used a structured checklist for observations and a semi-structured questionnaire for interviews in 24 homesteads. We also analysed the subject of 224 community calls to the project team for technical maintenance of SMoTS. Most respondents cared for SMoTS by fencing, emptying and cleaning the trap. Our observations revealed that most traps were fenced, clean and in good working condition. A significantly higher proportion of community calls was lighting-related. Lighting was the main reason respondents liked SMoTS because it reduced or eliminated expenditure on kerosene. However, some respondents observed they no longer heard sounds of mosquitoes inside their houses. All respondents reportedly slept under insecticide-treated nets (ITNs) before receiving SMoTS. After receiving SMoTS, most respondents reportedly continued to use ITNs citing that the project advised them to do so. Some beach residents stopped using ITNs because they no longer heard mosquitoes or due to heat discomfort caused by lights. Electricity-related incentives played a greater role in encouraging adherence to recommended behaviours for proper deployment of SMoTS than the potential health benefits in the early stages of the intervention. Although energy-related financial incentives may play a role, they are insufficient to ensure adherence to health advice, even in the short term. Ongoing community engagement and research monitors and addresses adherence to recommended behaviours including continuation of current malaria control strategies. © 2015 John Wiley & Sons Ltd.

  5. Molecular Characterization of Bovine SMO Gene and Effects of Its Genetic Variations on Body Size Traits in Qinchuan Cattle (Bos taurus).

    PubMed

    Zhang, Ya-Ran; Gui, Lin-Sheng; Li, Yao-Kun; Jiang, Bi-Jie; Wang, Hong-Cheng; Zhang, Ying-Ying; Zan, Lin-Sen

    2015-07-27

    Smoothened (Smo)-mediated Hedgehog (Hh) signaling pathway governs the patterning, morphogenesis and growth of many different regions within animal body plans. This study evaluated the effects of genetic variations of the bovine SMO gene on economically important body size traits in Chinese Qinchuan cattle. Altogether, eight single nucleotide polymorphisms (SNPs: 1-8) were identified and genotyped via direct sequencing covering most of the coding region and 3'UTR of the bovine SMO gene. Both the p.698Ser.>Ser. synonymous mutation resulted from SNP1 and the p.700Ser.>Pro. non-synonymous mutation caused by SNP2 mapped to the intracellular C-terminal tail of bovine Smo protein; the other six SNPs were non-coding variants located in the 3'UTR. The linkage disequilibrium was analyzed, and five haplotypes were discovered in 520 Qinchuan cattle. Association analyses showed that SNP2, SNP3/5, SNP4 and SNP6/7 were significantly associated with some body size traits (p < 0.05) except SNP1/8 (p > 0.05). Meanwhile, cattle with wild-type combined haplotype Hap1/Hap1 had significantly (p < 0.05) greater body length than those with Hap2/Hap2. Our results indicate that variations in the SMO gene could affect body size traits of Qinchuan cattle, and the wild-type haplotype Hap1 together with the wild-type alleles of these detected SNPs in the SMO gene could be used to breed cattle with superior body size traits. Therefore, our results could be helpful for marker-assisted selection in beef cattle breeding programs.

  6. Molecular Characterization of Bovine SMO Gene and Effects of Its Genetic Variations on Body Size Traits in Qinchuan Cattle (Bos taurus)

    PubMed Central

    Zhang, Ya-Ran; Gui, Lin-Sheng; Li, Yao-Kun; Jiang, Bi-Jie; Wang, Hong-Cheng; Zhang, Ying-Ying; Zan, Lin-Sen

    2015-01-01

    Smoothened (Smo)-mediated Hedgehog (Hh) signaling pathway governs the patterning, morphogenesis and growth of many different regions within animal body plans. This study evaluated the effects of genetic variations of the bovine SMO gene on economically important body size traits in Chinese Qinchuan cattle. Altogether, eight single nucleotide polymorphisms (SNPs: 1–8) were identified and genotyped via direct sequencing covering most of the coding region and 3ʹUTR of the bovine SMO gene. Both the p.698Ser.>Ser. synonymous mutation resulted from SNP1 and the p.700Ser.>Pro. non-synonymous mutation caused by SNP2 mapped to the intracellular C-terminal tail of bovine Smo protein; the other six SNPs were non-coding variants located in the 3ʹUTR. The linkage disequilibrium was analyzed, and five haplotypes were discovered in 520 Qinchuan cattle. Association analyses showed that SNP2, SNP3/5, SNP4 and SNP6/7 were significantly associated with some body size traits (p < 0.05) except SNP1/8 (p > 0.05). Meanwhile, cattle with wild-type combined haplotype Hap1/Hap1 had significantly (p < 0.05) greater body length than those with Hap2/Hap2. Our results indicate that variations in the SMO gene could affect body size traits of Qinchuan cattle, and the wild-type haplotype Hap1 together with the wild-type alleles of these detected SNPs in the SMO gene could be used to breed cattle with superior body size traits. Therefore, our results could be helpful for marker-assisted selection in beef cattle breeding programs. PMID:26225956

  7. Hedgehog signaling contributes to basic fibroblast growth factor-regulated fibroblast migration

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

    Zhu, Zhong Xin; Sun, Cong Cong; Wenzhou People's Hospital, Wenzhou, Zhejiang

    Fibroblast migration is a central process in skin wound healing, which requires the coordination of several types of growth factors. bFGF, a well-known fibroblast growth factor (FGF), is able to accelerate fibroblast migration; however, the underlying mechanism of bFGF regulation fibroblast migration remains unclear. Through the RNA-seq analysis, we had identified that the hedgehog (Hh) canonical pathway genes including Smoothened (Smo) and Gli1, were regulated by bFGF. Further analysis revealed that activation of the Hh pathway via up-regulation of Smo promoted fibroblast migration, invasion, and skin wound healing, but which significantly reduced by GANT61, a selective antagonist of Gli1/Gli2. Westernmore » blot analyses and siRNA transfection assays demonstrated that Smo acted upstream of phosphoinositide 3-kinase (PI3K)-c-Jun N-terminal kinase (JNK)-β-catenin to promote cell migration. Moreover, RNA-seq and qRT-PCR analyses revealed that Hh pathway genes including Smo and Gli1 were under control of β-catenin, suggesting that β-catenin turn feedback activates Hh signaling. Taken together, our analyses identified a new bFGF-regulating mechanism by which Hh signaling regulates human fibroblast migration, and the data presented here opens a new avenue for the wound healing therapy. - Highlights: • bFGF regulates Hedgehog (Hh) signaling in fibroblasts. • The Smo and Gli two master regulators of Hh signaling positively regulate fibroblast migration. • Smo facilitates β-catenin nuclear translocation via activation PI3K/JNK/GSK3β. • β-catenin positively regulates fibroblast cell migration and the expression of Hh signaling genes including Smo and Gli.« less

  8. GENERAL VIEW, LOOKING SOUTHEAST, OF STANDARDIZING MAGNETIC OBSERVATORY (SMO) WHICH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    GENERAL VIEW, LOOKING SOUTHEAST, OF STANDARDIZING MAGNETIC OBSERVATORY (SMO) WHICH IS TO THE RIGHT. THE BUILDING TO THE LEFT IS 'STATION 'A'', ALSO A NON-MAGNETIC STRUCTURE, ONCE USED FOR COMPARISONS OF MAGNETIC INSTRUMENTS WITH THE SMO. THE BUILDING IN THE CENTER CONTAINED A SEARCH-LIGHT USED IN CONJUNCTION WITH MEASUREMENTS OF THE EARTH'S ATMOSPHERE. - Carnegie Institution of Washington, Department of Terrestrial Magnetism, Standardizing Magnetic Observatory, 5241 Broad Branch Drive Northwest, Washington, District of Columbia, DC

  9. Dynamics of a bistable Miura-origami structure

    NASA Astrophysics Data System (ADS)

    Fang, Hongbin; Li, Suyi; Ji, Huimin; Wang, K. W.

    2017-05-01

    Origami-inspired structures and materials have shown extraordinary properties and performances originating from the intricate geometries of folding. However, current state of the art studies have mostly focused on static and quasistatic characteristics. This research performs a comprehensive experimental and analytical study on the dynamics of origami folding through investigating a stacked Miura-Ori (SMO) structure with intrinsic bistability. We fabricate and experimentally investigated a bistable SMO prototype with rigid facets and flexible crease lines. Under harmonic base excitation, the SMO exhibits both intrawell and interwell oscillations. Spectrum analyses reveal that the dominant nonlinearities of SMO are quadratic and cubic, which generate rich dynamics including subharmonic and chaotic oscillations. The identified nonlinearities indicate that a third-order polynomial can be employed to approximate the measured force-displacement relationship. Such an approximation is validated via numerical study by qualitatively reproducing the phenomena observed in the experiments. The dynamic characteristics of the bistable SMO resemble those of a Helmholtz-Duffing oscillator (HDO); this suggests the possibility of applying the established tools and insights of HDO to predict origami dynamics. We also show that the bistability of SMO can be programmed within a large design space via tailoring the crease stiffness and initial stress-free configurations. The results of this research offer a wealth of fundamental insights into the dynamics of origami folding, and provide a solid foundation for developing foldable and deployable structures and materials with embedded dynamic functionalities.

  10. Reduced Smoothened level rescues Aβ-induced memory deficits and neuronal inflammation in animal models of Alzheimer's disease.

    PubMed

    Ma, Weiwei; Wu, Mengnan; Zhou, Siyan; Tao, Ye; Xie, Zuolei; Zhong, Yi

    2018-05-20

    Emerging evidence suggests that neuro-inflammation begins early and drives the pathogenesis of Alzheimer's disease (AD), and anti-inflammatory therapies are under clinical development. However, several anti-inflammatory compounds failed to improve memory in clinical trials, indicating that reducing inflammation alone might not be enough. On the other hand, neuro-inflammation is implicated in a number of mental disorders which share the same therapeutic targets. Based on these observations, we screened a batch of genes related with mental disorder and neuro-inflammation in a classical olfactory conditioning in an amyloid beta (Aβ) overexpression fly model. A Smoothened (SMO) mutant was identified as a genetic modifier of Aβ toxicity in 3-min memory and downregulation of SMO rescued Aβ-induced 3-min and 1-h memory deficiency. Also, Aβ activated innate inflammatory response in fly by increasing the expression of antimicrobial peptides, which were alleviated by downregulating SMO. Furthermore, pharmaceutical administration of a SMO antagonist LDE rescued Aβ-induced upregulation of SMO in astrocytes of mouse hippocampus, improved memory in Morris water maze (MWM), and reduced expression of astrocyte secreting pro-inflammatory factors IL-1β, TNFα and the microglia marker IBA-1 in an APP/PS1 transgenic mouse model. Our study suggests that SMO is an important conserved modulator of Aβ toxicity in both fly and mouse models of AD. Copyright © 2018. Published by Elsevier Ltd.

  11. Design of a multistep phase mask for high-energy THz pulse generation in ZnTe crystal

    NASA Astrophysics Data System (ADS)

    Avetisyan, Yuri H.; Makaryan, Armen; Tadevosyan, Vahe

    2017-08-01

    A new scheme for generating high-energy terahertz (THz) pulses by optical rectification of tilted pulse front (TPF) femtosecond laser pulses in ZnTe crystal is proposed and analyzed. The TPF laser pulses are originated due to propagation through a multistep phase mask (MSPM) attached to the entrance surface of the nonlinear crystal. Similar to the case of contacting optical grating the necessity of the imaging optics is avoided. In addition, introduction of large amounts of angular dispersion is also eliminated. The operation principle is based on the fact that the MSPM splits a single input beam into many smaller time-delayed "beamlets", which together form a discretely TPF in the nonlinear crystal. The dimensions of the mask's steps required for high-energy THz-pulse generation in ZnTe and widely used lithium niobate (LN) crystals are calculated. The optimal number of steps is estimated taking into account individual beamlet's spatial broadening and problems related to the mask fabrication. The THz field in no pump depletion approximation is analytically calculated using radiating antenna model. The analysis shows that application of ZnTe crystal allows obtaining higher THz-pulse energy than that of LN crystal, especially when long-wavelength pump sources are used. The proposed method is a promising way to develop high-energy, monolithic, and alignment-free THzpulse source.

  12. On the effectiveness of noise masks: naturalistic vs. un-naturalistic image statistics.

    PubMed

    Hansen, Bruce C; Hess, Robert F

    2012-05-01

    It has been argued that the human visual system is optimized for identification of broadband objects embedded in stimuli possessing orientation averaged power spectra fall-offs that obey the 1/f(β) relationship typically observed in natural scene imagery (i.e., β=2.0 on logarithmic axes). Here, we were interested in whether individual spatial channels leading to recognition are functionally optimized for narrowband targets when masked by noise possessing naturalistic image statistics (β=2.0). The current study therefore explores the impact of variable β noise masks on the identification of narrowband target stimuli ranging in spatial complexity, while simultaneously controlling for physical or perceived differences between the masks. The results show that β=2.0 noise masks produce the largest identification thresholds regardless of target complexity, and thus do not seem to yield functionally optimized channel processing. The differential masking effects are discussed in the context of contrast gain control. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Patient with Gorlin syndrome and metastatic basal cell carcinoma refractory to smoothened inhibitors.

    PubMed

    Zhu, Gefei A; Li, Angela S; Chang, Anne Lynn S

    2014-08-01

    Basal cell carcinomas (BCCs) in patients with Gorlin syndrome have been reported to be extremely sensitive to Smoothened (SMO) inhibitors, a novel targeted therapy against the Hedgehog pathway, because of characteristic mutations in these patients. A few cases of disease refractory to oral therapy with SMO inhibitors have been reported in patients with Gorlin syndrome and nonmetastatic BCCs, but refractory disease in distantly metastatic tumors has not been documented in this high-risk group. A man with Gorlin syndrome and innumerable cutaneous BCCs presented with biopsy-proven BCC in his lungs. After SMO inhibitor therapy, almost all of his cutaneous tumors shrank, but his lung metastases did not. These lung metastases remained refractory to treatment despite institution of a second SMO inhibitor. We report a case of Gorlin syndrome in a patient with metastatic BCC refractory to SMO inhibitors. Furthermore, clinical responses in this patient's cutaneous tumors did not parallel the responses in the distant site. However, serial imaging after diagnosis of metastatic disease can be critical to monitor for response to therapy.

  14. Magnetic and electronic properties of SrMnO3 thin films

    NASA Astrophysics Data System (ADS)

    Mandal, Arup Kumar; Panchal, Gyanendra; Choudhary, R. J.; Phase, D. M.

    2018-05-01

    Single phase hexagonal bulk SrMnO3 (SMO) was prepared by solid state route and it was used for depositing thin films by pulsed laser deposition (PLD) technique on single crystalline (100) oriented SrTiO3 (STO) substrate. X-ray diffraction shows that the thin film is deposited in cubic SrMnO3 phase. From X-ray absorption at the Mn L edge we observed the mixed valency of Mn (Mn3+& Mn4+) due to strain induced by the lattice mismatching between SMO and STO. Due to this mixed valency of Mn ion in SMO film, the ferromagnetic nature is observed at lower temperature because of double exchange. After post annealing with very low oxygen partial pressure, magnetic and electronic property of SMO films are effectively modified.

  15. Optimizing the taste-masked formulation of acetaminophen using sodium caseinate and lecithin by experimental design.

    PubMed

    Hoang Thi, Thanh Huong; Lemdani, Mohamed; Flament, Marie-Pierre

    2013-09-10

    In a previous study of ours, the association of sodium caseinate and lecithin was demonstrated to be promising for masking the bitterness of acetaminophen via drug encapsulation. The encapsulating mechanisms were suggested to be based on the segregation of multicomponent droplets occurring during spray-drying. The spray-dried particles delayed the drug release within the mouth during the early time upon administration and hence masked the bitterness. Indeed, taste-masking is achieved if, within the frame of 1-2 min, drug substance is either not released or the released amount is below the human threshold for identifying its bad taste. The aim of this work was (i) to evaluate the effect of various processing and formulation parameters on the taste-masking efficiency and (ii) to determine the optimal formulation for optimal taste-masking effect. Four investigated input variables included inlet temperature (X1), spray flow (X2), sodium caseinate amount (X3) and lecithin amount (X4). The percentage of drug release amount during the first 2 min was considered as the response variable (Y). A 2(4)-full factorial design was applied and allowed screening for the most influential variables i.e. sodium caseinate amount and lecithin amount. Optimizing these two variables was therefore conducted by a simplex approach. The SEM and DSC results of spray-dried powder prepared under optimal conditions showed that drug seemed to be well encapsulated. The drug release during the first 2 min significantly decreased, 7-fold less than the unmasked drug particles. Therefore, the optimal formulation that performed the best taste-masking effect was successfully achieved. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Near-Infrared Spectroscopic Measurement of the Effect of Leg Dominance on Muscle Oxygen Saturation During Cycling

    NASA Technical Reports Server (NTRS)

    Ellerby, Gwenn E. C.; Lee, Stuart M. C.; Paunescu, Lelia Adelina; Pereira, Chelsea; Smith, Charles P.; Soller, Babs R.

    2011-01-01

    The effect of leg dominance on the symmetry of the biomechanics during cycling remains uncertain -- asymmetries have been observed in kinematics and kinetics, while symmetries were found in muscle activation. No studies have yet investigated the symmetry of muscle metabolism during cycling. Near-infrared spectroscopy (NIRS) provides a non-invasive method to investigate the metabolic responses of specific muscles during cycling. PURPOSE: To determine whether there was an effect of leg dominance on thigh muscle oxygen saturation (SmO2) during incrementally loaded submaximal cycling using NIRS. METHODS: Eight right leg dominant, untrained subjects (5 men, 3 women; 31+/-2 yrs; 168.6+/-1.0 cm; 67.2+/-1.8 kg, mean +/- SE) volunteered to participate. Spectra were collected bilaterally from the vastus lateralis (VL) during supine rest and cycling. SmO2 was calculated using previously published methods. Subjects pedaled at 65 rpm while resistance to pedaling was increased in 0.5 kp increments from 0.5 kp every 3 min until the subject reached 80% of age-predicted maximal heart rate. SmO2 was averaged over 3 min for each completed stage. A two-way ANOVA was performed to test for leg differences. A priori contrasts were used to compare work levels to rest. RESULTS: VL SmO2 was not different between the dominant and non-dominant legs at rest and during exercise (p=0.57). How SmO2 changed with workload was also not different between legs (p=0.32). SmO2 at 0.5 kp (60.3+/-4.0, p=0.12) and 1.0 kp (59.5+/-4.0, p=0.10) was not different from rest (69.1+/-4.0). SmO2 at 1.5 kp (55.4 4.0, p=0.02), 2.0 kp (55.7+/-5.0, p=0.04), and 2.5 kp (43.4+/-7.9, p=0.01) was significantly lower than rest. CONCLUSION: VL SmO2 during cycling is not different between dominant and non-dominant legs and decreases with moderate workload in untrained cyclists. Assuming blood flow is directed equally to both legs, similar levels of oxygen extraction (as indicated by SmO2) suggests the metabolic load of cycling is not different between legs. This is in agreement with a recent study demonstrating symmetrical increase of muscle activation of the VL during cycling. Leg dominance did not influence VL SmO2 during submaximal cycling, but may have an effect at higher loads or during other forms of exercise, such as walking and running.

  17. A method for evaluating the relation between sound source segregation and masking

    PubMed Central

    Lutfi, Robert A.; Liu, Ching-Ju

    2011-01-01

    Sound source segregation refers to the ability to hear as separate entities two or more sound sources comprising a mixture. Masking refers to the ability of one sound to make another sound difficult to hear. Often in studies, masking is assumed to result from a failure of segregation, but this assumption may not always be correct. Here a method is offered to identify the relation between masking and sound source segregation in studies and an example is given of its application. PMID:21302979

  18. Tunable wavefront coded imaging system based on detachable phase mask: Mathematical analysis, optimization and underlying applications

    NASA Astrophysics Data System (ADS)

    Zhao, Hui; Wei, Jingxuan

    2014-09-01

    The key to the concept of tunable wavefront coding lies in detachable phase masks. Ojeda-Castaneda et al. (Progress in Electronics Research Symposium Proceedings, Cambridge, USA, July 5-8, 2010) described a typical design in which two components with cosinusoidal phase variation operate together to make defocus sensitivity tunable. The present study proposes an improved design and makes three contributions: (1) A mathematical derivation based on the stationary phase method explains why the detachable phase mask of Ojeda-Castaneda et al. tunes the defocus sensitivity. (2) The mathematical derivations show that the effective bandwidth wavefront coded imaging system is also tunable by making each component of the detachable phase mask move asymmetrically. An improved Fisher information-based optimization procedure was also designed to ascertain the optimal mask parameters corresponding to specific bandwidth. (3) Possible applications of the tunable bandwidth are demonstrated by simulated imaging.

  19. Acyl-CoA-Binding Protein ACBP1 Modulates Sterol Synthesis during Embryogenesis1[OPEN

    PubMed Central

    Hsiao, An-Shan; Xue, Yan

    2017-01-01

    Fatty acids (FAs) and sterols are primary metabolites that exert interrelated functions as structural and signaling lipids. Despite their common syntheses from acetyl-coenzyme A, homeostatic cross talk remains enigmatic. Six Arabidopsis (Arabidopsis thaliana) acyl-coenzyme A-binding proteins (ACBPs) are involved in FA metabolism. ACBP1 interacts with PHOSPHOLIPASE Dα1 and regulates phospholipid composition. Here, its specific role in the negative modulation of sterol synthesis during embryogenesis is reported. ACBP1, likely in a liganded state, interacts with STEROL C4-METHYL OXIDASE1-1 (SMO1-1), a rate-limiting enzyme in the sterol pathway. Proembryo abortion in the double mutant indicated that the ACBP1-SMO1-1 interaction is synthetic lethal, corroborating with their strong promoter activities in developing ovules. Gas chromatography-mass spectrometry revealed quantitative and compositional changes in FAs and sterols upon overexpression or mutation of ACBP1 and/or SMO1-1. Aberrant levels of these metabolites may account for the downstream defect in lipid signaling. GLABRA2 (GL2), encoding a phospholipid/sterol-binding homeodomain transcription factor, was up-regulated in developing seeds of acbp1, smo1-1, and ACBP1+/−smo1-1 in comparison with the wild type. Consistent with the corresponding transcriptional alteration of GL2 targets, high-oil, low-mucilage phenotypes of gl2 were phenocopied in ACBP1+/−smo1-1. Thus, ACBP1 appears to modulate the metabolism of two important lipid classes (FAs and sterols) influencing cellular signaling. PMID:28500265

  20. Masking Strategies for Image Manifolds.

    PubMed

    Dadkhahi, Hamid; Duarte, Marco F

    2016-07-07

    We consider the problem of selecting an optimal mask for an image manifold, i.e., choosing a subset of the pixels of the image that preserves the manifold's geometric structure present in the original data. Such masking implements a form of compressive sensing through emerging imaging sensor platforms for which the power expense grows with the number of pixels acquired. Our goal is for the manifold learned from masked images to resemble its full image counterpart as closely as possible. More precisely, we show that one can indeed accurately learn an image manifold without having to consider a large majority of the image pixels. In doing so, we consider two masking methods that preserve the local and global geometric structure of the manifold, respectively. In each case, the process of finding the optimal masking pattern can be cast as a binary integer program, which is computationally expensive but can be approximated by a fast greedy algorithm. Numerical experiments show that the relevant manifold structure is preserved through the datadependent masking process, even for modest mask sizes.

  1. Validation of Procedures for Monitoring Crewmember Immune Function SDBI-1900, SMO-015 - Integrated Immune

    NASA Technical Reports Server (NTRS)

    Crucian, Brian; Stowe, Raymond; Mehta, Satish; Uchakin, Peter; Nehlsen-Cannarella, Sandra; Morukov, Boris; Pierson, Duane; Sams, Clarence

    2007-01-01

    There is ample evidence to suggest that space flight leads to immune system dysregulation. This may be a result of microgravity, confinement, physiological stress, radiation, environment or other mission-associated factors. The clinical risk from prolonged immune dysregulation during space flight are not yet determined, but may include increased incidence of infection, allergy, hypersensitivity, hematological malignancy or altered wound healing. Each of the clinical events resulting from immune dysfunction has the potential to impact mission critical objectives during exploration-class missions. To date, precious little in-flight immune data has been generated to assess this phenomenon. The majority of recent flight immune studies have been post-flight assessments, which may not accurately reflect the in-flight condition. There are no procedures currently in place to monitor immune function or its effect on crew health. The objective of this Supplemental Medical Objective (SMO) is to develop and validate an immune monitoring strategy consistent with operational flight requirements and constraints. This SMO will assess the clinical risks resulting from the adverse effects of space flight on the human immune system and will validate a flight-compatible immune monitoring strategy. Characterization of the clinical risk and the development of a monitoring strategy are necessary prerequisite activities prior to validating countermeasures. This study will determine, to the best level allowed by current technology, the in-flight status of crewmembers immune system. Pre-flight, in-flight and post-flight assessments of immune status, immune function, viral reactivation and physiological stress will be performed. The in-flight samples will allow a distinction between legitimate in-flight alterations and the physiological stresses of landing and readaptation which are believed to alter landing day assessments. The overall status of the immune system during flight (activation, deficiency, dysregulation) and the response of the immune system to specific latent virus reactivation (known to occur during space flight) will be thoroughly assessed. Following completion of the SMO the data will be evaluated to determine the optimal set of assays for routine monitoring of crewmember immune system function, should the clinical risk warrant such monitoring.

  2. Serial robot for the trajectory optimization and error compensation of TMT mask exchange system

    NASA Astrophysics Data System (ADS)

    Wang, Jianping; Zhang, Feifan; Zhou, Zengxiang; Zhai, Chao

    2015-10-01

    Mask exchange system is the main part of Multi-Object Broadband Imaging Echellette (MOBIE) on the Thirty Meter Telescope (TMT). According to the conception of the TMT mask exchange system, the pre-design was introduced in the paper which was based on IRB 140 robot. The stiffness model of IRB 140 in SolidWorks was analyzed under different gravity vectors for further error compensation. In order to find the right location and path planning, the robot and the mask cassette model was imported into MOBIE model to perform different schemes simulation. And obtained the initial installation position and routing. Based on these initial parameters, IRB 140 robot was operated to simulate the path and estimate the mask exchange time. Meanwhile, MATLAB and ADAMS software were used to perform simulation analysis and optimize the route to acquire the kinematics parameters and compare with the experiment results. After simulation and experimental research mentioned in the paper, the theoretical reference was acquired which could high efficient improve the structure of the mask exchange system parameters optimization of the path and precision of the robot position.

  3. The efficacy of novel anatomical sites for the assessment of muscle oxygenation during central hypovolemia.

    PubMed

    Sprick, Justin D; Soller, Babs R; Rickards, Caroline A

    2016-11-01

    Muscle tissue oxygenation (SmO 2 ) can track central blood volume loss associated with hemorrhage. Traditional peripheral measurement sites (e.g., forearm) may not be practical due to excessive movement or injury (e.g., amputation). The aim of this study was to evaluate the efficacy of three novel anatomical sites for the assessment of SmO 2 under progressive central hypovolemia. 10 male volunteers were exposed to stepwise prone lower body negative pressure to decrease central blood volume, while SmO 2 was assessed at four sites-the traditional site of the flexor carpi ulnaris (ARM), and three novel sites not previously investigated during lower body negative pressure, the deltoid, latissimus dorsi, and trapezius. SmO 2 at the novel sites was compared to the ARM sensor and to stroke volume responses. A reduction in SmO 2 was detected by the ARM sensor at the first level of lower body negative pressure (-15 mmHg; P = 0.007), and at -30 (the deltoid), -45 (latissimus dorsi), and -60 mmHg lower body negative pressure (trapezius) at the novel sites (P ≤ 0.04). SmO 2 responses at all novel sites were correlated with responses at the ARM (R ≥ 0.89), and tracked the reduction in stroke volume (R ≥ 0.87); the latissimus dorsi site exhibited the strongest linear correlations (R ≥ 0.96). Of the novel sensor sites, the latissimus dorsi exhibited the strongest linear associations with SmO 2 at the ARM, and with reductions in central blood volume. These findings have important implications for detection of hemorrhage in austere environments (e.g., combat) when use of a peripheral sensor may not be ideal, and may facilitate incorporation of these sensors into uniforms. © 2016 by the Society for Experimental Biology and Medicine.

  4. Infrared spectra and density functional calculations for SMO2 molecules (M = Cr, Mo, W).

    PubMed

    Wang, Xuefeng; Andrews, Lester

    2009-08-06

    Infrared absorptions of the matrix isolated SMO2 (M = Cr, Mo, W) molecules were observed following laser-ablated metal atom reactions with SO2 during condensation in solid argon and neon. The symmetric and antisymmetric M-O stretching mode assignments were confirmed by appropriate S18O2 and S(16,18)O2 isotopic shifts. The much weaker Cr-S stretching mode was identified through its 34S shift. Density functional (B3LYP and BPW91) calculations were performed to obtain molecular structures and to reproduce the infrared spectra. Computed pyramidal structures for the SMO2 molecules are very similar to those for the analogous trioxides and this functional group in [MO2S(bdt)]2- complexes. Additional weaker absorptions are assigned to the (SO2)(SMO2) adducts, which are stabilized by a four-membered ring.

  5. Sensorless control of ship propulsion interior permanent magnet synchronous motor based on a new sliding mode observer.

    PubMed

    Ren, Jun-Jie; Liu, Yan-Cheng; Wang, Ning; Liu, Si-Yuan

    2015-01-01

    This paper proposes a sensorless speed control strategy for ship propulsion interior permanent magnet synchronous motor (IPMSM) based on a new sliding-mode observer (SMO). In the SMO the low-pass filter and the method of arc-tangent calculation of extended electromotive force (EMF) or phase-locked loop (PLL) technique are not used. The calculation of the rotor speed is deduced from the Lyapunov function stability analysis. In order to reduce system chattering, sigmoid functions with switching gains being adaptively updated by fuzzy logic systems are innovatively incorporated into the SMO. Finally, simulation results for a 4.088 MW ship propulsion IPMSM and experimental results from a 7.5 kW IPMSM drive are provided to verify the effectiveness of the proposed SMO method. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  6. Structure of the human smoothened receptor 7TM bound to an antitumor agent

    PubMed Central

    Wang, Chong; Wu, Huixian; Katritch, Vsevolod; Han, Gye Won; Huang, Xi-Ping; Liu, Wei; Siu, Fai Yiu; Roth, Bryan L.; Cherezov, Vadim; Stevens, Raymond C.

    2013-01-01

    The smoothened (SMO) receptor, a key signal transducer in the Hedgehog (Hh) signaling pathway is both responsible for the maintenance of normal embryonic development and implicated in carcinogenesis. The SMO receptor is classified as a class Frizzled (class F) G protein-coupled receptor (GPCR), although the canonical Hh signaling pathway involves the transcription factor Gli and the sequence similarity with class A GPCRs is less than 10%. Here we report the crystal structure at 2.5 Å resolution of the transmembrane domain of the human SMO receptor bound to the small molecule antagonist LY2940680. Although the SMO receptor shares the seven transmembrane helical (7TM) fold, most conserved motifs for class A GPCRs are absent, and the structure reveals an unusually complex arrangement of long extracellular loops stabilized by four disulfide bonds. The ligand binds at the extracellular end of the 7TM bundle and forms extensive contacts with the loops. PMID:23636324

  7. Acyl-CoA-Binding Protein ACBP1 Modulates Sterol Synthesis during Embryogenesis.

    PubMed

    Lung, Shiu-Cheung; Liao, Pan; Yeung, Edward C; Hsiao, An-Shan; Xue, Yan; Chye, Mee-Len

    2017-07-01

    Fatty acids (FAs) and sterols are primary metabolites that exert interrelated functions as structural and signaling lipids. Despite their common syntheses from acetyl-coenzyme A, homeostatic cross talk remains enigmatic. Six Arabidopsis ( Arabidopsis thaliana ) acyl-coenzyme A-binding proteins (ACBPs) are involved in FA metabolism. ACBP1 interacts with PHOSPHOLIPASE Dα1 and regulates phospholipid composition. Here, its specific role in the negative modulation of sterol synthesis during embryogenesis is reported. ACBP1, likely in a liganded state, interacts with STEROL C4-METHYL OXIDASE1-1 (SMO1-1), a rate-limiting enzyme in the sterol pathway. Proembryo abortion in the double mutant indicated that the ACBP1-SMO1-1 interaction is synthetic lethal, corroborating with their strong promoter activities in developing ovules. Gas chromatography-mass spectrometry revealed quantitative and compositional changes in FAs and sterols upon overexpression or mutation of ACBP1 and/or SMO1-1 Aberrant levels of these metabolites may account for the downstream defect in lipid signaling. GLABRA2 ( GL2 ), encoding a phospholipid/sterol-binding homeodomain transcription factor, was up-regulated in developing seeds of acbp1 , smo1-1 , and ACBP1 +/- smo1-1 in comparison with the wild type. Consistent with the corresponding transcriptional alteration of GL2 targets, high-oil, low-mucilage phenotypes of gl2 were phenocopied in ACBP1 +/- smo1-1 Thus, ACBP1 appears to modulate the metabolism of two important lipid classes (FAs and sterols) influencing cellular signaling. © 2017 American Society of Plant Biologists. All Rights Reserved.

  8. Crystal structure of a multi-domain human smoothened receptor in complex with a super stabilizing ligand

    DOE PAGES

    Zhang, Xianjun; Zhao, Fei; Wu, Yiran; ...

    2017-05-17

    Here, the Smoothened receptor (SMO) belongs to the Class Frizzled of the G protein-coupled receptor (GPCR) superfamily, constituting a key component of the Hedgehog signalling pathway. Here we report the crystal structure of the multi-domain human SMO, bound and stabilized by a designed tool ligand TC114, using an X-ray free-electron laser source at 2.9 Å. The structure reveals a precise arrangement of three distinct domains: a seven-transmembrane helices domain (TMD), a hinge domain (HD) and an intact extracellular cysteine-rich domain (CRD). This architecture enables allosteric interactions between the domains that are important for ligand recognition and receptor activation. By combiningmore » the structural data, molecular dynamics simulation, and hydrogen-deuterium-exchange analysis, we demonstrate that transmembrane helix VI, extracellular loop 3 and the HD play a central role in transmitting the signal employing a unique GPCR activation mechanism, distinct from other multi-domain GPCRs.« less

  9. OPC and PSM design using inverse lithography: a nonlinear optimization approach

    NASA Astrophysics Data System (ADS)

    Poonawala, Amyn; Milanfar, Peyman

    2006-03-01

    We propose a novel method for the fast synthesis of low complexity model-based optical proximity correction (OPC) and phase shift masks (PSM) to improve the resolution and pattern fidelity of optical microlithography. We use the pixel-based mask representation, a continuous function formulation, and gradient based iterative optimization techniques to solve the above inverse problem. The continuous function formulation allows analytic calculation of the gradient. Pixel-based parametrization provides tremendous liberty in terms of the features possible in the synthesized masks, but also suffers the inherent disadvantage that the masks are very complex and difficult to manufacture. We therefore introduce the regularization framework; a useful tool which provides the flexibility to promote certain desirable properties in the solution. We employ the above framework to ensure that the estimated masks have only two or three (allowable) transmission values and are also comparatively simple and easy to manufacture. The results demonstrate that we are able to bring the CD on target using OPC masks. Furthermore, we were also able to boost the contrast of the aerial image using attenuated, strong, and 100% transmission phase shift masks. Our algorithm automatically (and optimally) adds assist-bars, dog-ears, serifs, anti-serifs, and other custom structures best suited for printing the desired pattern.

  10. Alternative method for variable aspect ratio vias using a vortex mask

    NASA Astrophysics Data System (ADS)

    Schepis, Anthony R.; Levinson, Zac; Burbine, Andrew; Smith, Bruce W.

    2014-03-01

    Historically IC (integrated circuit) device scaling has bridged the gap between technology nodes. Device size reduction is enabled by increased pattern density, enhancing functionality and effectively reducing cost per chip. Exemplifying this trend are aggressive reductions in memory cell sizes that have resulted in systems with diminishing area between bit/word lines. This affords an even greater challenge in the patterning of contact level features that are inherently difficult to resolve because of their relatively small area and complex aerial image. To accommodate these trends, semiconductor device design has shifted toward the implementation of elliptical contact features. This empowers designers to maximize the use of free device space, preserving contact area and effectively reducing the via dimension just along a single axis. It is therefore critical to provide methods that enhance the resolving capacity of varying aspect ratio vias for implementation in electronic design systems. Vortex masks, characterized by their helically induced propagation of light and consequent dark core, afford great potential for the patterning of such features when coupled with a high resolution negative tone resist system. This study investigates the integration of a vortex mask in a 193nm immersion (193i) lithography system and qualifies its ability to augment aspect ratio through feature density using aerial image vector simulation. It was found that vortex fabricated vias provide a distinct resolution advantage over traditionally patterned contact features employing a 6% attenuated phase shift mask (APM). 1:1 features were resolvable at 110nm pitch with a 38nm critical dimension (CD) and 110nm depth of focus (DOF) at 10% exposure latitude (EL). Furthermore, iterative source-mask optimization was executed as means to augment aspect ratio. By employing mask asymmetries and directionally biased sources aspect ratios ranging between 1:1 and 2:1 were achievable, however, this range is ultimately dictated by pitch employed.

  11. Effects of bovine SMO gene polymorphisms on the body measurement and meat quality traits of Qinchuan cattle.

    PubMed

    Zhang, Y R; Li, Y K; Fu, C Z; Wang, J L; Wang, H B; Zan, L S

    2014-10-07

    Beef cattle breeding programs focus on improving important economic traits, including growth rates, and meat quantity and quality. Molecular marker-assisted selection based on genetic variation represents a potential method for breeding genetically improved livestock with better economic traits. Smoothened (SMO) protein is a signal transducer that contributes to the regulation of both osteogenesis and adipogenesis through the hedgehog pathway. In this study, we detected polymorphisms in the bovine SMO gene of Qinchuan cattle, and we analyzed their associations with body measurement traits (BMTs) and meat quality traits (MQTs). Using DNA sequencing and polymerase chain reaction-restriction fragment length polymorphism, 3 novel single nucleotide polymorphisms were identified in the SMO gene of 562 cattle: 1 G > C mutation on exon 9 (G21234C) and 2 C > T mutations on exon 11 (C22424T and C22481T). Association analysis showed that polymorphisms on both the G21234C and C22424T loci significantly affected certain BMTs and MQTs (P < 0.05 or P < 0.01), whereas those on the C22481T locus did not (P > 0.05). Therefore, the SMO gene could be used as a candidate gene to alter BMTs and MQTs in Qinchuan cattle or for marker-assisted selection to breed cattle with superior BMTs and MQTs.

  12. Regaining motor control in musician's dystonia by restoring sensorimotor organisation

    PubMed Central

    Rosenkranz, Karin; Butler, Katherine; Williamon, Aaron; Rothwell, John C.

    2010-01-01

    Professional musicians are an excellent human model of long term effects of skilled motor training on the structure and function of the motor system. However, such effects are accompanied by an increased risk of developing motor abnormalities, in particular musician's dystonia. Previously we found that there was an expanded spatial integration of proprioceptive input into the hand area of motor cortex (sensorimotor organisation, SMO) in healthy musicians as tested with a transcranial magnetic stimulation (TMS) paradigm. In musician's dystonia, this expansion was even larger, resulting in a complete lack of somatotopic organisation. We hypothesised that the disordered motor control in musician's dystonia is a consequence of the disordered SMO. In the present paper we test this idea by giving pianists with musician's dystonia 15 min experience of a modified proprioceptive training task. This restored SMO towards that seen in healthy pianists. Crucially, motor control of the affected task improved significantly and objectively as measured with a MIDI piano, and the amount of behavioural improvement was significantly correlated to the degree of sensorimotor re-organisation. In healthy pianists and non-musicians, the SMO and motor performance remained essentially unchanged. These findings suggest a link between the differentiation of SMO in the hand motor cortex and the degree of motor control of intensively practiced tasks in highly skilled individuals. PMID:19923295

  13. Identification of optimal mask size parameter for noise filtering in 99mTc-methylene diphosphonate bone scintigraphy images.

    PubMed

    Pandey, Anil K; Bisht, Chandan S; Sharma, Param D; ArunRaj, Sreedharan Thankarajan; Taywade, Sameer; Patel, Chetan; Bal, Chandrashekhar; Kumar, Rakesh

    2017-11-01

    Tc-methylene diphosphonate (Tc-MDP) bone scintigraphy images have limited number of counts per pixel. A noise filtering method based on local statistics of the image produces better results than a linear filter. However, the mask size has a significant effect on image quality. In this study, we have identified the optimal mask size that yields a good smooth bone scan image. Forty four bone scan images were processed using mask sizes 3, 5, 7, 9, 11, 13, and 15 pixels. The input and processed images were reviewed in two steps. In the first step, the images were inspected and the mask sizes that produced images with significant loss of clinical details in comparison with the input image were excluded. In the second step, the image quality of the 40 sets of images (each set had input image, and its corresponding three processed images with 3, 5, and 7-pixel masks) was assessed by two nuclear medicine physicians. They selected one good smooth image from each set of images. The image quality was also assessed quantitatively with a line profile. Fisher's exact test was used to find statistically significant differences in image quality processed with 5 and 7-pixel mask at a 5% cut-off. A statistically significant difference was found between the image quality processed with 5 and 7-pixel mask at P=0.00528. The identified optimal mask size to produce a good smooth image was found to be 7 pixels. The best mask size for the John-Sen Lee filter was found to be 7×7 pixels, which yielded Tc-methylene diphosphonate bone scan images with the highest acceptable smoothness.

  14. Plasma formed ion beam projection lithography system

    DOEpatents

    Leung, Ka-Ngo; Lee, Yung-Hee Yvette; Ngo, Vinh; Zahir, Nastaran

    2002-01-01

    A plasma-formed ion-beam projection lithography (IPL) system eliminates the acceleration stage between the ion source and stencil mask of a conventional IPL system. Instead a much thicker mask is used as a beam forming or extraction electrode, positioned next to the plasma in the ion source. Thus the entire beam forming electrode or mask is illuminated uniformly with the source plasma. The extracted beam passes through an acceleration and reduction stage onto the resist coated wafer. Low energy ions, about 30 eV, pass through the mask, minimizing heating, scattering, and sputtering.

  15. Sorption of selected veterinary antibiotics onto dairy farming soils of contrasting nature.

    PubMed

    Srinivasan, Prakash; Sarmah, Ajit K; Manley-Harris, Merilyn

    2014-02-15

    The sorption potential for three sulfonamides (SAs), sulfamethoxazole (SMO), sulfachloropyridazine (SCP) and sulfamethazine (SM) and a macrolide, tylosin tartrate (TT) was assessed on six New Zealand dairy farming soils of contrasting physico-chemical properties. Kinetics studies showed that the sorption was rapid in the first few hours of the contact time (0-2h for SA and 0-4h for TT) and thereafter apparent equilibrium was achieved. Batch sorption isotherm data revealed that the degree of isotherm linearity (N) for SCP and SM varied between 0.50 and 1.08 in the six soils. Isotherms of both TT and SMO were mostly non-linear with the degree of non-linearity for TT (N=0.38-0.71) being greater than for SMO (0.42-0.75) in all soils except Manawatu (TT) and Te Kowhai (SMO) where a linear pattern was observed. Concentration-dependent effective distribution coefficient (Kd(eff)) values for the SMO, SCP and SM antibiotics in the soils ranged from 0.85 to 16.35 L kg(-1), while that for TT was 1.6 to 1,042 L kg(-1). The sorption affinity for all soils followed an order: TT>SCP>SM>SMO. Remarkable high sorption for tylosin in Matawhero soil as compared to other soils was attributed to the presence of oxygen containing acidic polar functional groups as evident in the FT-IR spectra of the soil. Furthermore, it was hypothesised that sorption of TT onto soils was mostly driven by metal oxide-surface mediated transformations whereas for sulfonamides it was primarily due to hydrophobic interactions. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. The α Subunit of the G Protein G13 Regulates Activity of One or More Gli Transcription Factors Independently of Smoothened*

    PubMed Central

    Douglas, Andrew E.; Heim, Jennifer A.; Shen, Feng; Almada, Luciana L.; Riobo, Natalia A.; Fernández-Zapico, Martin E.; Manning, David R.

    2011-01-01

    Smoothened (Smo) is a seven-transmembrane (7-TM) receptor that is essential to most actions of the Hedgehog family of morphogens. We found previously that Smo couples to members of the Gi family of heterotrimeric G proteins, which in some cases are integral although alone insufficient in the activation of Gli transcription factors through Hedgehog signaling. In response to a report that the G12/13 family is relevant to Hedgehog signaling as well, we re-evaluated the coupling of Smo to one member of this family, G13, and investigated the capacity of this and other G proteins to activate one or more of forms of Gli. We found no evidence that Smo couples directly to G13. We found nonetheless that Gα13 and to some extent Gαq and Gα12 are able to effect activation of Gli(s). This capacity is realized in some cells, e.g. C3H10T1/2, MC3T3, and pancreatic cancer cells, but not all cells. The mechanism employed is distinct from that achieved through canonical Hedgehog signaling, as the activation does not involve autocrine signaling or in any other way require active Smo and does not necessarily involve enhanced transcription of Gli1. The activation by Gα13 can be replicated through a Gq/G12/13-coupled receptor, CCKA, and is attenuated by inhibitors of p38 mitogen-activated protein kinase and Tec tyrosine kinases. We posit that G proteins, and perhaps G13 in particular, provide access to Gli that is independent of Smo and that they thus establish a basis for control of at least some forms of Gli-mediated transcription apart from Hedgehogs. PMID:21757753

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

    Ge, Xin; Lyu, Pengwei; Gu, Yuanting

    Sonic hesgehog (Shh) signaling has been reported to play an essential role in cancer progression. The mechanism of Shh involved in breast cancer carcinogenesis remains unclear. The present study sought to explore whether Shh signaling could regulate the glycolytic metabolism in breast cancers. Overexpression of the smoothed (Smo) and Gli-1 was found in human primary breast cancers. The expressions of Shh and Gli-1 correlated significantly with tumor size and tumor stage. In vitro, human recombinant Shh (rShh) triggered Smo and Gli-1 expression, promoted glucose utilization and lactate production, and accelerated cell proliferation in MCF-7 and MDA-MB-231 cells. Notably, rShh did notmore » alter 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) expression but augmented PFKFB3 phosphorylation on ser{sup 461}, along with elevated fructose-2,6-bisphosphate (F2,6BP) generation by MCF-7 and MDA-MB-231 cells. This effect could be dampened by Smo siRNA but not by Gli-1 siRNA. In addition, our data showed the upregulated expressions of MAPK by rShh and elevatory PFKFB3 phosphorylation by p38/MAPK activated kinase (MK2). In conclusion, our study characterized a novel role of Shh in promoting glycolysis and proliferation of breast cancer cells via PFKFB3 phosphorylation, which was mediated by Smo and p38/MK2. - Highlights: • Overexpression of Smo and Gli-1 was found in human primary breast cancers. • Shh promoted glucose utilization, lactate production, and cell proliferation. • Shh did not alter PFKFB3 expression but augmented PFKFB3 phosphorylation on ser461. • Shh acts on PFKFB3 phosphorylation via Smo and p38 MAPK/MK2.« less

  18. Synthesis of bilayer MoS{sub 2} nanosheets by a facile hydrothermal method and their methyl orange adsorption capacity

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

    Ye, Lijuan; Xu, Haiyan; Zhang, Dingke

    2014-07-01

    Highlights: • Hexagonal phase of MoS{sub 2} nanosheets was synthesized by a facile hydrothermal method. • FE-SEM and TEM images show the sheets-like morphology of MoS{sub 2}. • Bilayer MoS{sub 2} can be grown under the optimized mole ratio of 2:1 of S:Mo at 180 °C for 50 h. • The MoS{sub 2} nanosheets possess high methyl orange adsorption capacity due to the large surface area. - Abstract: Molybdenum disulfide (MoS{sub 2}) nanosheets have received significant attention recently due to the potential applications for exciting physics and technology. Here we show that MoS{sub 2} nanosheets can be prepared by amore » facile hydrothermal method. The study of the properties of the MoS{sub 2} nanosheets prepared at different conditions suggests that the mole ratio of precursors and hydrothermal time significantly influences the purity, crystalline quality and thermal stability of MoS{sub 2}. X-ray diffraction, Raman spectra and transmission electron microscopy results indicate that bilayer MoS{sub 2} can be grown under an optimized mole ratio of 2:1 of S:Mo at 180 °C for 50 h. Moreover, such ultrathin nanosheets exhibit a prominent photoluminescence and possess high methyl orange adsorption capacity due to the large surface area, which can be potentially used in photodevice and photochemical catalyst.« less

  19. Optimization of a methamphetamine conjugate vaccine for antibody production in mice.

    PubMed

    Stevens, Misty W; Gunnell, Melinda G; Tawney, Rachel; Owens, S Michael

    2016-06-01

    There are still no approved medications for treating patients who abuse methamphetamine. Active vaccines for treating abuse of nicotine and cocaine are in clinical studies, but have not proven effective seemingly due to inadequate anti-drug antibody production. The current studies aimed to optimize the composition, adjuvant and route of administration of a methamphetamine conjugate vaccine, ICKLH-SMO9, in mice with the goal of generating significantly higher antibody levels. A range of hapten epitope densities were compared, as were the adjuvants Alhydrogel and a new Toll-like receptor 4 (TLR4) agonist called GLA-SE. While methamphetamine hapten density did not strongly affect the antibody response, the adjuvant did. Glucopyranosyl lipid A in a stable oil-in-water emulsion (GLA-SE) produced much higher levels of antibody in response to immunization compared with Alhydrogel; immunization with GLA-SE also produced antibodies with higher affinities for methamphetamine. GLA-SE has been used in human studies of vaccines for influenza among others and like some other clinical TLR4 agonists, it is safe and elicits a strong immune response. GLA-SE adjuvanted vaccines are typically administered by intramuscular injection and this also proved effective in these mouse studies. Clinical studies of the ICKLH-SMO9 methamphetamine vaccine adjuvanted with GLA-SE have the potential for demonstrating efficacy by generating much higher levels of antibody than substance abuse vaccines that have unsuccessfully used aluminum-based adjuvants. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Decoding the phosphorylation code in Hedgehog signal transduction

    PubMed Central

    Chen, Yongbin; Jiang, Jin

    2013-01-01

    Hedgehog (Hh) signaling plays pivotal roles in embryonic development and adult tissue homeostasis, and its deregulation leads to numerous human disorders including cancer. Binding of Hh to Patched (Ptc), a twelve-transmembrane protein, alleviates its inhibition of Smoothened (Smo), a seven-transmembrane protein related to G-protein-coupled receptors (GPCRs), leading to Smo phosphorylation and activation. Smo acts through intracellular signaling complexes to convert the latent transcription factor Cubitus interruptus (Ci)/Gli from a truncated repressor to a full-length activator, leading to derepression/activation of Hh target genes. Increasing evidence suggests that phosphorylation participates in almost every step in the signal relay from Smo to Ci/Gli, and that differential phosphorylation of several key pathway components may be crucial for translating the Hh morphogen gradient into graded pathway activities. In this review, we focus on the multifaceted roles that phosphorylation plays in Hh signal transduction, and discuss the conservation and difference between Drosophila and mammalian Hh signaling mechanisms. PMID:23337587

  1. Sonic hedgehog signaling regulates actin cytoskeleton via Tiam1-Rac1 cascade during spine formation.

    PubMed

    Sasaki, Nobunari; Kurisu, Junko; Kengaku, Mineko

    2010-12-01

    The sonic hedgehog (Shh) pathway has essential roles in several processes during development of the vertebrate central nervous system (CNS). Here, we report that Shh regulates dendritic spine formation in hippocampal pyramidal neurons via a novel pathway that directly regulates the actin cytoskeleton. Shh signaling molecules Patched (Ptc) and Smoothened (Smo) are expressed in several types of postmitotic neurons, including cerebellar Purkinje cells and hippocampal pyramidal neurons. Knockdown of Smo induces dendritic spine formation in cultured hippocampal neurons independently of Gli-mediated transcriptional activity. Smo interacts with Tiam1, a guanine nucleotide exchange factor for Rac1, via its cytoplasmic C-terminal region. Inhibition of Tiam1 or Rac1 activity suppresses spine induction by Smo knockdown. Shh induces remodeling of the actin cytoskeleton independently of transcriptional activation in mouse embryonic fibroblasts. These findings demonstrate a novel Shh pathway that regulates the actin cytoskeleton via Tiam1-Rac1 activation. Copyright © 2010 Elsevier Inc. All rights reserved.

  2. Peptide amphiphile nanofiber hydrogel delivery of sonic hedgehog protein to the cavernous nerve to promote regeneration and prevent erectile dysfunction.

    PubMed

    Choe, Shawn; Bond, Christopher W; Harrington, Daniel A; Stupp, Samuel I; McVary, Kevin T; Podlasek, Carol A

    2017-01-01

    Erectile dysfunction (ED) has high impact on quality of life in prostatectomy, diabetic and aging patients. An underlying mechanism is cavernous nerve (CN) injury, which causes ED in up to 80% of prostatectomy patients. We examine how sonic hedgehog (SHH) treatment with innovative peptide amphiphile nanofiber hydrogels (PA), promotes CN regeneration after injury. SHH and its receptors patched (PTCH1) and smoothened (SMO) are localized in PG neurons and glia. SMO undergoes anterograde transport to signal to downstream targets. With crush injury, PG neurons degenerate and undergo apoptosis. SHH protein decreases, SMO localization changes to the neuronal cell surface, and anterograde transport stops. With SHH treatment SHH is taken up at the injury site and undergoes retrograde transport to PG neurons, allowing SMO transport to occur, and neurons remain intact. SHH treatment prevents neuronal degeneration, maintains neuronal, glial and downstream target signaling, and is significant as a regenerative therapy. Published by Elsevier Inc.

  3. Cholesterol activates the G-protein coupled receptor Smoothened to promote Hedgehog signaling

    PubMed Central

    Luchetti, Giovanni; Sircar, Ria; Kong, Jennifer H; Nachtergaele, Sigrid; Sagner, Andreas; Byrne, Eamon FX; Covey, Douglas F; Siebold, Christian; Rohatgi, Rajat

    2016-01-01

    Cholesterol is necessary for the function of many G-protein coupled receptors (GPCRs). We find that cholesterol is not just necessary but also sufficient to activate signaling by the Hedgehog (Hh) pathway, a prominent cell-cell communication system in development. Cholesterol influences Hh signaling by directly activating Smoothened (SMO), an orphan GPCR that transmits the Hh signal across the membrane in all animals. Unlike many GPCRs, which are regulated by cholesterol through their heptahelical transmembrane domains, SMO is activated by cholesterol through its extracellular cysteine-rich domain (CRD). Residues shown to mediate cholesterol binding to the CRD in a recent structural analysis also dictate SMO activation, both in response to cholesterol and to native Hh ligands. Our results show that cholesterol can initiate signaling from the cell surface by engaging the extracellular domain of a GPCR and suggest that SMO activity may be regulated by local changes in cholesterol abundance or accessibility. DOI: http://dx.doi.org/10.7554/eLife.20304.001 PMID:27705744

  4. High brightness electrodeless Z-Pinch EUV source for mask inspection tools

    NASA Astrophysics Data System (ADS)

    Horne, Stephen F.; Partlow, Matthew J.; Gustafson, Deborah S.; Besen, Matthew M.; Smith, Donald K.; Blackborow, Paul A.

    2012-03-01

    Energetiq Technology has been shipping the EQ-10 Electrodeless Z-pinchTM light source since 1995. The source is currently being used for metrology, mask inspection, and resist development. Energetiq's higher brightness source has been selected as the source for pre-production actinic mask inspection tools. This improved source enables the mask inspection tool suppliers to build prototype tools with capabilities of defect detection and review down to 16nm design rules. In this presentation we will present new source technology being developed at Energetiq to address the critical source brightness issue. The new technology will be shown to be capable of delivering brightness levels sufficient to meet the HVM requirements of AIMS and ABI and potentially API tools. The basis of the source technology is to use the stable pinch of the electrodeless light source and have a brightness of up to 100W/mm(carat)2-sr. We will explain the source design concepts, discuss the expected performance and present the modeling results for the new design.

  5. A new predictive model for continuous positive airway pressure in the treatment of obstructive sleep apnea.

    PubMed

    Ebben, Matthew R; Narizhnaya, Mariya; Krieger, Ana C

    2017-05-01

    Numerous mathematical formulas have been developed to determine continuous positive airway pressure (CPAP) without an in-laboratory titration study. Recent studies have shown that style of CPAP mask can affect the optimal pressure requirement. However, none of the current models take mask style into account. Therefore, the goal of this study was to develop new predictive models of CPAP that take into account the style of mask interface. Data from 200 subjects with attended CPAP titrations during overnight polysomnograms using nasal masks and 132 subjects using oronasal masks were randomized and split into either a model development or validation group. Predictive models were then created in each model development group and the accuracy of the models was then tested in the model validation groups. The correlation between our new oronasal model and laboratory determined optimal CPAP was significant, r = 0.61, p < 0.001. Our nasal formula was also significantly related to laboratory determined optimal CPAP, r = 0.35, p < 0.001. The oronasal model created in our study significantly outperformed the original CPAP predictive model developed by Miljeteig and Hoffstein, z = 1.99, p < 0.05. The predictive performance of our new nasal model did not differ significantly from Miljeteig and Hoffstein's original model, z = -0.16, p < 0.90. The best predictors for the nasal mask group were AHI, lowest SaO2, and neck size, whereas the top predictors in the oronasal group were AHI and lowest SaO2. Our data show that predictive models of CPAP that take into account mask style can significantly improve the formula's accuracy. Most of the past models likely focused on model development with nasal masks (mask style used for model development was not typically reported in previous investigations) and are not well suited for patients using an oronasal interface. Our new oronasal CPAP prediction equation produced significantly improved performance compared to the well-known Miljeteig and Hoffstein formula in patients titrated on CPAP with an oronasal mask and was also significantly related to laboratory determined optimal CPAP.

  6. Muscle Oxygen Saturation Improves Diagnostic Association Between Initial Vital Signs and Major Hemorrhage: A Prospective Observational Study.

    PubMed

    Reisner, Andrew T; Edla, Shwetha; Liu, Jianbo; Rubin, John T; Thorsen, Jill E; Kittell, Erin; Smith, Jason B; Yeh, Daniel D; Reifman, Jaques

    2016-03-01

    During initial assessment of trauma patients, vital signs do not identify all patients with life-threatening hemorrhage. We hypothesized that a novel vital sign, muscle oxygen saturation (SmO2 ), could provide independent diagnostic information beyond routine vital signs for identification of hemorrhaging patients who require packed red blood cell (RBC) transfusion. This was an observational study of adult trauma patients treated at a Level I trauma center. Study staff placed the CareGuide 1100 tissue oximeter (Reflectance Medical Inc., Westborough, MA), and we analyzed average values of SmO2 , systolic blood pressure (sBP), pulse pressure (PP), and heart rate (HR) during 10 minutes of early emergency department evaluation. We excluded subjects without a full set of vital signs during the observation interval. The study outcome was hemorrhagic injury and RBC transfusion ≥ 3 units in 24 hours (24-hr RBC ≥ 3). To test the hypothesis that SmO2 added independent information beyond routine vital signs, we developed one logistic regression model with HR, sBP, and PP and one with SmO2 in addition to HR, sBP, and PP and compared their areas under receiver operating characteristic curves (ROC AUCs) using DeLong's test. We enrolled 487 subjects; 23 received 24-hr RBC ≥ 3. Compared to the model without SmO2 , the regression model with SmO2 had a significantly increased ROC AUC for the prediction of ≥ 3 units of 24-hr RBC volume, 0.85 (95% confidence interval [CI], 0.75-0.91) versus 0.77 (95% CI, 0.66-0.86; p < 0.05 per DeLong's test). Results were similar for ROC AUCs predicting patients (n = 11) receiving 24-hr RBC ≥ 9. SmO2 significantly improved the diagnostic association between initial vital signs and hemorrhagic injury with blood transfusion. This parameter may enhance the early identification of patients who require blood products for life-threatening hemorrhage. © 2016 The Authors. Academic Emergency Medicine published by Wiley Periodicals, Inc. on behalf of Society for Academic Emergency Medicine.

  7. Masks For Deposition Of Aspherical Optical Surfaces

    NASA Technical Reports Server (NTRS)

    Rogers, John R.; Martin, John D.

    1992-01-01

    Masks of improved design developed for use in fabrication of aspherical, rotationally symmetrical surfaces of mirrors, lenses, and lens molds by evaporative deposition onto rotating substrates. In deposition chamber, source and mask aligned with axis of rotation of substrate. Mask shadows source of rotating substrate. Azimuthal opening (as function of radius) in mask proportional to desired thickness (as function of radius) to which material deposited on substrate. Combination of improved masks and modern coating chambers provides optical surfaces comparable or superior to those produced by conventional polishing, computer-controlled polishing, replication from polished molds, and diamond turning, at less cost in material, labor, and capital expense.

  8. Spontaneous sulfur dioxide activation by Group V metal (V, Nb, Ta) atoms in excess argon at cryogenic temperatures.

    PubMed

    Liu, Xing; Wang, Xuefeng; Wang, Qiang; Andrews, Lester

    2013-06-28

    Reactions of laser-ablated V, Nb and Ta atoms with SO2 in excess argon during condensation gave new absorptions in the M=O stretching region, which were assigned to metal sulfide oxides SMO2 and anions SMO2(-) (M = V, Nb, Ta). The metal oxide complex OV(η(2)-SO) was also identified through the V=O and the characteristic side-on coordinated S-O stretching modes. The assignments of major vibrational modes were confirmed by appropriate S(18)O2 and (34)SO2 isotopic shifts, and density functional frequency calculations. DFT calculations were employed to study the behavior of reactions of Group V bare metal atoms with SO2, and a representative profile was derived which not only showed the preferred coordinating fashion of metal atoms but also tracked the path of S-O bond activation. The η(2)-O,O' bridge coordinated complexes are preferred with energy decreases of ca. 50 kcal mol(-1) for all three metals, which facilitate the activation of two S-O bonds in succession and finally direct the reaction to the most stable molecules SMO2 (M = V, Nb, Ta) along the potential energy surface (PES). Finally the SMO2 molecules capture electrons to give anions SMO2(-) with about 3.6 eV electron affinities based on DFT calculations.

  9. Mask etcher data strategy for 45nm and beyond

    NASA Astrophysics Data System (ADS)

    Lewington, Richard; Ibrahim, Ibrahim M.; Panayil, Sheeba; Kumar, Ajay; Yamartino, John

    2006-05-01

    Mask Etching for the 45nm technology node and beyond requires a system-level data and diagnostics strategy. This necessity stems from the need to control the performance of the mask etcher to increasingly stringent and diverse requirements of the mask production environment. Increasing mask costs and the capability to acquire and consolidate a wealth of data within the mask etch platform are primary motivators towards harnessing data mines for feedback into the mask etching optimization. There are offline and real-time possibilities and scenarios. Here, we discuss the data architecture, acquisition, and strategies of the Applied Materials Tetra II TM Mask Etch System.

  10. Long range personalized cancer treatment strategies incorporating evolutionary dynamics.

    PubMed

    Yeang, Chen-Hsiang; Beckman, Robert A

    2016-10-22

    Current cancer precision medicine strategies match therapies to static consensus molecular properties of an individual's cancer, thus determining the next therapeutic maneuver. These strategies typically maintain a constant treatment while the cancer is not worsening. However, cancers feature complicated sub-clonal structure and dynamic evolution. We have recently shown, in a comprehensive simulation of two non-cross resistant therapies across a broad parameter space representing realistic tumors, that substantial improvement in cure rates and median survival can be obtained utilizing dynamic precision medicine strategies. These dynamic strategies explicitly consider intratumoral heterogeneity and evolutionary dynamics, including predicted future drug resistance states, and reevaluate optimal therapy every 45 days. However, the optimization is performed in single 45 day steps ("single-step optimization"). Herein we evaluate analogous strategies that think multiple therapeutic maneuvers ahead, considering potential outcomes at 5 steps ahead ("multi-step optimization") or 40 steps ahead ("adaptive long term optimization (ALTO)") when recommending the optimal therapy in each 45 day block, in simulations involving both 2 and 3 non-cross resistant therapies. We also evaluate an ALTO approach for situations where simultaneous combination therapy is not feasible ("Adaptive long term optimization: serial monotherapy only (ALTO-SMO)"). Simulations utilize populations of 764,000 and 1,700,000 virtual patients for 2 and 3 drug cases, respectively. Each virtual patient represents a unique clinical presentation including sizes of major and minor tumor subclones, growth rates, evolution rates, and drug sensitivities. While multi-step optimization and ALTO provide no significant average survival benefit, cure rates are significantly increased by ALTO. Furthermore, in the subset of individual virtual patients demonstrating clinically significant difference in outcome between approaches, by far the majority show an advantage of multi-step or ALTO over single-step optimization. ALTO-SMO delivers cure rates superior or equal to those of single- or multi-step optimization, in 2 and 3 drug cases respectively. In selected virtual patients incurable by dynamic precision medicine using single-step optimization, analogous strategies that "think ahead" can deliver long-term survival and cure without any disadvantage for non-responders. When therapies require dose reduction in combination (due to toxicity), optimal strategies feature complex patterns involving rapidly interleaved pulses of combinations and high dose monotherapy. This article was reviewed by Wendy Cornell, Marek Kimmel, and Andrzej Swierniak. Wendy Cornell and Andrzej Swierniak are external reviewers (not members of the Biology Direct editorial board). Andrzej Swierniak was nominated by Marek Kimmel.

  11. Polyamine Analogues as Novel Anti-HER Family Agents in Human Breast Cancer

    DTIC Science & Technology

    2007-09-01

    Davidson NE, & Casero RA Jr. Spermine oxidase SMO(PAOh1), not N1-acetylpolyamine oxidase PAO, is the primary source of cytotoxic H2O2 in polyamine...Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Elevated levels of all three naturally occurring polyamines, spermine , spermidine and...protein in multiple human breast cancer cell lines. This suppression is both time and dose dependent. A relationship between oligoamine structure , growth

  12. Identification of Dust Source Regions at High-Resolution and Dynamics of Dust Source Mask over Southwest United States Using Remote Sensing Data

    NASA Astrophysics Data System (ADS)

    Sprigg, W. A.; Sahoo, S.; Prasad, A. K.; Venkatesh, A. S.; Vukovic, A.; Nickovic, S.

    2015-12-01

    Identification and evaluation of sources of aeolian mineral dust is a critical task in the simulation of dust. Recently, time series of space based multi-sensor satellite images have been used to identify and monitor changes in the land surface characteristics. Modeling of windblown dust requires precise delineation of mineral dust source and its strength that varies over a region as well as seasonal and inter-annual variability due to changes in land use and land cover. Southwest USA is one of the major dust emission prone zone in North American continent where dust is generated from low lying dried-up areas with bare ground surface and they may be scattered or appear as point sources on high resolution satellite images. In the current research, various satellite derived variables have been integrated to produce a high-resolution dust source mask, at grid size of 250 m, using data such as digital elevation model, surface reflectance, vegetation cover, land cover class, and surface wetness. Previous dust source models have been adopted to produce a multi-parameter dust source mask using data from satellites such as Terra (Moderate Resolution Imaging Spectroradiometer - MODIS), and Landsat. The dust source mask model captures the topographically low regions with bare soil surface, dried-up river plains, and lakes which form important source of dust in southwest USA. The study region is also one of the hottest regions of USA where surface dryness, land use (agricultural use), and vegetation cover changes significantly leading to major changes in the areal coverage of potential dust source regions. A dynamic high resolution dust source mask have been produced to address intra-annual change in the aerial extent of bare dry surfaces. Time series of satellite derived data have been used to create dynamic dust source masks. A new dust source mask at 16 day interval allows enhanced detection of potential dust source regions that can be employed in the dust emission and transport pathways models for better estimation of emission of dust during dust storms, particulate air pollution, public health risk assessment tools and decision support systems.

  13. Strategy optimization for mask rule check in wafer fab

    NASA Astrophysics Data System (ADS)

    Yang, Chuen Huei; Lin, Shaina; Lin, Roger; Wang, Alice; Lee, Rachel; Deng, Erwin

    2015-07-01

    Photolithography process is getting more and more sophisticated for wafer production following Moore's law. Therefore, for wafer fab, consolidated and close cooperation with mask house is a key to achieve silicon wafer success. However, generally speaking, it is not easy to preserve such partnership because many engineering efforts and frequent communication are indispensable. The inattentive connection is obvious in mask rule check (MRC). Mask houses will do their own MRC at job deck stage, but the checking is only for identification of mask process limitation including writing, etching, inspection, metrology, etc. No further checking in terms of wafer process concerned mask data errors will be implemented after data files of whole mask are composed in mask house. There are still many potential data errors even post-OPC verification has been done for main circuits. What mentioned here are the kinds of errors which will only occur as main circuits combined with frame and dummy patterns to form whole reticle. Therefore, strategy optimization is on-going in UMC to evaluate MRC especially for wafer fab concerned errors. The prerequisite is that no impact on mask delivery cycle time even adding this extra checking. A full-mask checking based on job deck in gds or oasis format is necessary in order to secure acceptable run time. Form of the summarized error report generated by this checking is also crucial because user friendly interface will shorten engineers' judgment time to release mask for writing. This paper will survey the key factors of MRC in wafer fab.

  14. A reduced-order nonlinear sliding mode observer for vehicle slip angle and tyre forces

    NASA Astrophysics Data System (ADS)

    Chen, Yuhang; Ji, Yunfeng; Guo, Konghui

    2014-12-01

    In this paper, a reduced-order sliding mode observer (RO-SMO) is developed for vehicle state estimation. Several improvements are achieved in this paper. First, the reference model accuracy is improved by considering vehicle load transfers and using a precise nonlinear tyre model 'UniTire'. Second, without the reference model accuracy degraded, the computing burden of the state observer is decreased by a reduced-order approach. Third, nonlinear system damping is integrated into the SMO to speed convergence and reduce chattering. The proposed RO-SMO is evaluated through simulation and experiments based on an in-wheel motor electric vehicle. The results show that the proposed observer accurately predicts the vehicle states.

  15. Lithographic process window optimization for mask aligner proximity lithography

    NASA Astrophysics Data System (ADS)

    Voelkel, Reinhard; Vogler, Uwe; Bramati, Arianna; Erdmann, Andreas; Ünal, Nezih; Hofmann, Ulrich; Hennemeyer, Marc; Zoberbier, Ralph; Nguyen, David; Brugger, Juergen

    2014-03-01

    We introduce a complete methodology for process window optimization in proximity mask aligner lithography. The commercially available lithography simulation software LAB from GenISys GmbH was used for simulation of light propagation and 3D resist development. The methodology was tested for the practical example of lines and spaces, 5 micron half-pitch, printed in a 1 micron thick layer of AZ® 1512HS1 positive photoresist on a silicon wafer. A SUSS MicroTec MA8 mask aligner, equipped with MO Exposure Optics® was used in simulation and experiment. MO Exposure Optics® is the latest generation of illumination systems for mask aligners. MO Exposure Optics® provides telecentric illumination and excellent light uniformity over the full mask field. MO Exposure Optics® allows the lithography engineer to freely shape the angular spectrum of the illumination light (customized illumination), which is a mandatory requirement for process window optimization. Three different illumination settings have been tested for 0 to 100 micron proximity gap. The results obtained prove, that the introduced process window methodology is a major step forward to obtain more robust processes in mask aligner lithography. The most remarkable outcome of the presented study is that a smaller exposure gap does not automatically lead to better print results in proximity lithography - what the "good instinct" of a lithographer would expect. With more than 5'000 mask aligners installed in research and industry worldwide, the proposed process window methodology might have significant impact on yield improvement and cost saving in industry.

  16. VUV lithography

    DOEpatents

    George, Edward V.; Oster, Yale; Mundinger, David C.

    1990-01-01

    Deep UV projection lithography can be performed using an e-beam pumped solid excimer UV source, a mask, and a UV reduction camera. The UV source produces deep UV radiation in the range 1700-1300A using xenon, krypton or argon; shorter wavelengths of 850-650A can be obtained using neon or helium. A thin solid layer of the gas is formed on a cryogenically cooled plate and bombarded with an e-beam to cause fluorescence. The UV reduction camera utilizes multilayer mirrors having high reflectivity at the UV wavelength and images the mask onto a resist coated substrate at a preselected demagnification. The mask can be formed integrally with the source as an emitting mask.

  17. CoSMoS: Conserved Sequence Motif Search in the proteome

    PubMed Central

    Liu, Xiao I; Korde, Neeraj; Jakob, Ursula; Leichert, Lars I

    2006-01-01

    Background With the ever-increasing number of gene sequences in the public databases, generating and analyzing multiple sequence alignments becomes increasingly time consuming. Nevertheless it is a task performed on a regular basis by researchers in many labs. Results We have now created a database called CoSMoS to find the occurrences and at the same time evaluate the significance of sequence motifs and amino acids encoded in the whole genome of the model organism Escherichia coli K12. We provide a precomputed set of multiple sequence alignments for each individual E. coli protein with all of its homologues in the RefSeq database. The alignments themselves, information about the occurrence of sequence motifs together with information on the conservation of each of the more than 1.3 million amino acids encoded in the E. coli genome can be accessed via the web interface of CoSMoS. Conclusion CoSMoS is a valuable tool to identify highly conserved sequence motifs, to find regions suitable for mutational studies in functional analyses and to predict important structural features in E. coli proteins. PMID:16433915

  18. GLI activation by atypical protein kinase C ι/λ regulates the growth of basal cell carcinomas.

    PubMed

    Atwood, Scott X; Li, Mischa; Lee, Alex; Tang, Jean Y; Oro, Anthony E

    2013-02-28

    Growth of basal cell carcinomas (BCCs) requires high levels of hedgehog (HH) signalling through the transcription factor GLI. Although inhibitors of membrane protein smoothened (SMO) effectively suppress HH signalling, early tumour resistance illustrates the need for additional downstream targets for therapy. Here we identify atypical protein kinase C ι/λ (aPKC-ι/λ) as a novel GLI regulator in mammals. aPKC-ι/λ and its polarity signalling partners co-localize at the centrosome and form a complex with missing-in-metastasis (MIM), a scaffolding protein that potentiates HH signalling. Genetic or pharmacological loss of aPKC-ι/λ function blocks HH signalling and proliferation of BCC cells. Prkci is a HH target gene that forms a positive feedback loop with GLI and exists at increased levels in BCCs. Genome-wide transcriptional profiling shows that aPKC-ι/λ and SMO control the expression of similar genes in tumour cells. aPKC-ι/λ functions downstream of SMO to phosphorylate and activate GLI1, resulting in maximal DNA binding and transcriptional activation. Activated aPKC-ι/λ is upregulated in SMO-inhibitor-resistant tumours and targeting aPKC-ι/λ suppresses signalling and growth of resistant BCC cell lines. These results demonstrate that aPKC-ι/λ is critical for HH-dependent processes and implicates aPKC-ι/λ as a new, tumour-selective therapeutic target for the treatment of SMO-inhibitor-resistant cancers.

  19. CoSMoS and TwinPaW: initial report on two new German twin studies.

    PubMed

    Spinath, Frank M; Wolf, Heike

    2006-12-01

    After briefly recapitulating two earlier German twin studies (BiLSAT and GOSAT), we present two new German twin studies with a longitudinal perspective: CoSMoS and TwinPaW. The twin study on Cognitive ability, Self-reported Motivation and School performance (CoSMoS) aims to investigate predictors and influences of school performance in a genetically sensitive design, beginning with children in late elementary school. The Twin study on Personality And Wellbeing (TwinPaW) focuses on adult personality and its relation to physical health as well as health-related behavior in an adult sample of twins. Both studies are characterized by an effort to recruit new large twin samples through a novel recruitment procedure aimed at reducing self-selective sampling. In two German federal states, contact information on persons born on the same day and with the same name was retrieved from record sections. From the resulting pool of more than 36,000 addresses we contacted approximately 2000 parents of twins aged 9 and 10 for CoSMoS, as well as 2000 adult twin pairs for TwinPaW by telephone and mail. Personal contact by telephone proved to be more efficient with agreement rates of 63% in the children sample and 65% in the adult sample. In this article we briefly describe the rationale and the study aims of CoSMoS and TwinPaW as well as the characteristics of the sample we have recruited so far.

  20. Optimal mask characterization by Surrogate Wafer Print (SWaP) method

    NASA Astrophysics Data System (ADS)

    Kimmel, Kurt R.; Hoellein, Ingo; Peters, Jan Hendrick; Ackmann, Paul; Connolly, Brid; West, Craig

    2008-10-01

    Traditionally, definition of mask specifications is done completely by the mask user, while characterization of the mask relative to the specifications is done completely by the mask maker. As the challenges of low-k1 imaging continue to grow in scope of designs and in absolute complexity, the inevitable partnership between wafer lithographers and mask makers has strengthened as well. This is reflected in the jointly owned mask facilities and device manufacturers' continued maintenance of fully captive mask shops which foster the closer mask-litho relationships. However, while some device manufacturers have leveraged this to optimize mask specifications before the mask is built and, therefore, improve mask yield and cost, the opportunity for post-fabrication partnering on mask characterization is more apparent and compelling. The Advanced Mask Technology Center (AMTC) has been investigating the concept of assessing how a mask images, rather than the mask's physical attributes, as a technically superior and lower-cost method to characterize a mask. The idea of printing a mask under its intended imaging conditions, then characterizing the imaged wafer as a surrogate for traditional mask inspections and measurements represents the ultimate method to characterize a mask's performance, which is most meaningful to the user. Surrogate wafer print (SWaP) is already done as part of leading-edge wafer fab mask qualification to validate defect and dimensional performance. In the past, the prospect of executing this concept has generally been summarily discarded as technically untenable and logistically intractable. The AMTC published a paper at BACUS 2007 successfully demonstrating the performance of SWaP for the characterization of defects as an alternative to traditional mask inspection [1]. It showed that this concept is not only feasible, but, in some cases, desirable. This paper expands on last year's work at AMTC to assess the full implementation of SWaP as an enhancement to mask characterization quality including defectivity, dimensional control, pattern fidelity, and in-plane distortion. We present a thorough analysis of both the technical and logistical challenges coupled with an objective view of the advantages and disadvantages from both the technical and financial perspectives. The analysis and model used by the AMTC will serve to provoke other mask shops to prepare their own analyses then consider this new paradigm for mask characterization and qualification.

  1. Stenotrophomonas maltophilia responds to exogenous AHL signals through the LuxR solo SmoR (Smlt1839).

    PubMed

    Martínez, Paula; Huedo, Pol; Martinez-Servat, Sònia; Planell, Raquel; Ferrer-Navarro, Mario; Daura, Xavier; Yero, Daniel; Gibert, Isidre

    2015-01-01

    Quorum Sensing (QS) mediated by Acyl Homoserine Lactone (AHL) molecules are probably the most widespread and studied among Gram-negative bacteria. Canonical AHL systems are composed by a synthase (LuxI family) and a regulator element (LuxR family), whose genes are usually adjacent in the genome. However, incomplete AHL-QS machinery lacking the synthase LuxI is frequently observed in Proteobacteria, and the regulator element is then referred as LuxR solo. It has been shown that certain LuxR solos participate in interspecific communication by detecting signals produced by different organisms. In the case of Stenotrophomonas maltophilia, a preliminary genome sequence analysis revealed numerous putative luxR genes, none of them associated to a luxI gene. From these, the hypothetical LuxR solo Smlt1839, here designated SmoR, presents a conserved AHL binding domain and a helix-turn-helix DNA binding motif. Its genomic organization-adjacent to hchA gene-indicate that SmoR belongs to the new family "LuxR regulator chaperone HchA-associated." AHL-binding assays revealed that SmoR binds to AHLs in-vitro, at least to oxo-C8-homoserine lactone, and it regulates operon transcription, likely by recognizing a conserved palindromic regulatory box in the hchA upstream region. Supplementation with concentrated supernatants from Pseudomonas aeruginosa, which contain significant amounts of AHLs, promoted swarming motility in S. maltophilia. Contrarily, no swarming stimulation was observed when the P. aeruginosa supernatant was treated with the lactonase AiiA from Bacillus subtilis, confirming that AHL contributes to enhance the swarming ability of S. maltophilia. Finally, mutation of smoR resulted in a swarming alteration and an apparent insensitivity to the exogenous AHLs provided by P. aeruginosa. In conclusion, our results demonstrate that S. maltophilia senses AHLs produced by neighboring bacteria through the LuxR solo SmoR, regulating population behaviors such as swarming motility.

  2. Design of aerosol face masks for children using computerized 3D face analysis.

    PubMed

    Amirav, Israel; Luder, Anthony S; Halamish, Asaf; Raviv, Dan; Kimmel, Ron; Waisman, Dan; Newhouse, Michael T

    2014-08-01

    Aerosol masks were originally developed for adults and downsized for children. Overall fit to minimize dead space and a tight seal are problematic, because children's faces undergo rapid and marked topographic and internal anthropometric changes in their first few months/years of life. Facial three-dimensional (3D) anthropometric data were used to design an optimized pediatric mask. Children's faces (n=271, aged 1 month to 4 years) were scanned with 3D technology. Data for the distance from the bridge of the nose to the tip of the chin (H) and the width of the mouth opening (W) were used to categorize the scans into "small," "medium," and "large" "clusters." "Average" masks were developed from each cluster to provide an optimal seal with minimal dead space. The resulting computerized contour, W and H, were used to develop the SootherMask® that enables children, "suckling" on their own pacifier, to keep the mask on their face, mainly by means of subatmospheric pressure. The relatively wide and flexible rim of the mask accommodates variations in facial size within and between clusters. Unique pediatric face masks were developed based on anthropometric data obtained through computerized 3D face analysis. These masks follow facial contours and gently seal to the child's face, and thus may minimize aerosol leakage and dead space.

  3. SeaWiFS technical report series. Volume 31: Stray light in the SeaWiFS radiometer

    NASA Technical Reports Server (NTRS)

    Hooker, Stanford B. (Editor); Firestone, Elaine R. (Editor); Acker, James G. (Editor); Barnes, Robert A.; Holmes, Alan W.; Esaias, Wayne E.

    1995-01-01

    Some of the measurements from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) will not be useful as ocean measurements. For the ocean data set, there are procedures in place to mask the SeaWiFS measurements of clouds and ice. Land measurements will also be masked using a geographic technique based on each measurment's latitude and longitude. Each of these masks involves a source of light much brighter than the ocean. Because of stray light in the SeaWiFS radiometer, light from these bright sources can contaminate ocean measurements located a variable number of pixels away from a bright source. In this document, the sources of stray light in the sensor are examined, and a method is developed for masking measurements near bright targets for stray light effects. In addition, a procedure is proposed for reducing the effects of stray light in the flight data from SeaWiFS. This correction can also reduce the number of pixels masked for stray light. Without these corrections, local area scenes must be masked 10 pixels before and after bright targets in the along-scan direction. The addition of these corrections reduces the along-scan masks to four pixels before and after bright sources. In the along-track direction, the flight data are not corrected, and are masked two pixels before and after. Laboratory measurements have shown that stray light within the instrument changes in a direct ratio to the intensity of the bright source. The measurements have also shown that none of the bands show peculiarities in their stray light response. In other words, the instrument's response is uniform from band to band. The along-scan correction is based on each band's response to a 1 pixel wide bright sources. Since these results are based solely on preflight laboratory measurements, their successful implementation requires compliance with two additional criteria. First, since SeaWiFS has a large data volume, the correction and masking procedures must be such that they can be converted into computationally fast algorithms. Second, they must be shown to operate properly on flight data. The laboratory results, and the corrections and masking procedures that derive from them, should be considered as zeroeth order estimates of the effects that will be found on orbit.

  4. Amine oxidase-based biosensors for spermine and spermidine determination.

    PubMed

    Boffi, Alberto; Favero, Gabriele; Federico, Rodolfo; Macone, Alberto; Antiochia, Riccarda; Tortolini, Cristina; Sanzó, Gabriella; Mazzei, Franco

    2015-02-01

    The present work describes the development and optimization of electrochemical biosensors for specific determination of the biogenic polyamine spermine (Spm) and spermidine (Spmd) whose assessment represents a novel important analytical tool in food analysis and human diagnostics. These biosensors have been prepared using novel engineered enzymes: polyamine oxidase (PAO) endowed with selectivity towards Spm and Spmd and spermine oxidase (SMO) characterized by strict specificity towards Spm. The current design entails biosensors in which the enzymes were entrapped in poly(vinyl alcohol) bearing styrylpyridinium groups (PVA-SbQ), a photocrosslinkable gel, onto an electrode surface. Screen-printed electrodes (SPEs) were used as electrochemical transducers for enzymatically produced hydrogen peroxide, operating at different potential vs Ag/AgCl according to the material of the working electrode (WE): +700 mV for graphite (GP) or -100 mV for Prussian blue (PB)-modified SPE, respectively. Biosensor performances were evaluated by means of flow injection amperometric (FIA) measurements. The modified electrodes showed good sensitivity, long-term stability and reproducibility. Under optimal conditions, the PAO biosensor showed a linear range 0.003-0.3 mM for Spm and 0.01-0.4 mM for Spmd, while with the SMO biosensor, a linear range of 0.004-0.5 mM for Spm has been obtained. The main kinetic parameters apparent Michaelis constant (K M), turnover number (K cat) and steady-state current (I max) were determined. The proposed device was then applied to the determination of biogenic amines in blood samples. The results obtained were in good agreement with those obtained with the GC-MS reference method.

  5. The influence of negative training set size on machine learning-based virtual screening.

    PubMed

    Kurczab, Rafał; Smusz, Sabina; Bojarski, Andrzej J

    2014-01-01

    The paper presents a thorough analysis of the influence of the number of negative training examples on the performance of machine learning methods. The impact of this rather neglected aspect of machine learning methods application was examined for sets containing a fixed number of positive and a varying number of negative examples randomly selected from the ZINC database. An increase in the ratio of positive to negative training instances was found to greatly influence most of the investigated evaluating parameters of ML methods in simulated virtual screening experiments. In a majority of cases, substantial increases in precision and MCC were observed in conjunction with some decreases in hit recall. The analysis of dynamics of those variations let us recommend an optimal composition of training data. The study was performed on several protein targets, 5 machine learning algorithms (SMO, Naïve Bayes, Ibk, J48 and Random Forest) and 2 types of molecular fingerprints (MACCS and CDK FP). The most effective classification was provided by the combination of CDK FP with SMO or Random Forest algorithms. The Naïve Bayes models appeared to be hardly sensitive to changes in the number of negative instances in the training set. In conclusion, the ratio of positive to negative training instances should be taken into account during the preparation of machine learning experiments, as it might significantly influence the performance of particular classifier. What is more, the optimization of negative training set size can be applied as a boosting-like approach in machine learning-based virtual screening.

  6. The influence of negative training set size on machine learning-based virtual screening

    PubMed Central

    2014-01-01

    Background The paper presents a thorough analysis of the influence of the number of negative training examples on the performance of machine learning methods. Results The impact of this rather neglected aspect of machine learning methods application was examined for sets containing a fixed number of positive and a varying number of negative examples randomly selected from the ZINC database. An increase in the ratio of positive to negative training instances was found to greatly influence most of the investigated evaluating parameters of ML methods in simulated virtual screening experiments. In a majority of cases, substantial increases in precision and MCC were observed in conjunction with some decreases in hit recall. The analysis of dynamics of those variations let us recommend an optimal composition of training data. The study was performed on several protein targets, 5 machine learning algorithms (SMO, Naïve Bayes, Ibk, J48 and Random Forest) and 2 types of molecular fingerprints (MACCS and CDK FP). The most effective classification was provided by the combination of CDK FP with SMO or Random Forest algorithms. The Naïve Bayes models appeared to be hardly sensitive to changes in the number of negative instances in the training set. Conclusions In conclusion, the ratio of positive to negative training instances should be taken into account during the preparation of machine learning experiments, as it might significantly influence the performance of particular classifier. What is more, the optimization of negative training set size can be applied as a boosting-like approach in machine learning-based virtual screening. PMID:24976867

  7. VUV lithography

    DOEpatents

    George, E.V.; Oster, Y.; Mundinger, D.C.

    1990-12-25

    Deep UV projection lithography can be performed using an e-beam pumped solid excimer UV source, a mask, and a UV reduction camera. The UV source produces deep UV radiation in the range 1,700--1,300A using xenon, krypton or argon; shorter wavelengths of 850--650A can be obtained using neon or helium. A thin solid layer of the gas is formed on a cryogenically cooled plate and bombarded with an e-beam to cause fluorescence. The UV reduction camera utilizes multilayer mirrors having high reflectivity at the UV wavelength and images the mask onto a resist coated substrate at a preselected demagnification. The mask can be formed integrally with the source as an emitting mask. 6 figs.

  8. SLC injector modeling

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

    Hanerfeld, H; Herrmannsfeldt, W.B.; James, M.B.

    1985-03-01

    The injector for the Stanford Linear Collider is being studied using the fully electromagnetic particle-in-cell program MASK. The program takes account of cylindrically symmetrical rf fields from the external source, as well as fields produced by the beam and dc magnetic fields. It calculates the radial and longitudinal motion of electrons and plots their positions in various planes in phase space. Bunching parameters can be optimized and insights into the bunching process and emittance growth have been gained. The results of the simulations are compared to the experimental results.

  9. Masking release by combined spatial and masker-fluctuation effects in the open sound field.

    PubMed

    Middlebrooks, John C

    2017-12-01

    In a complex auditory scene, signals of interest can be distinguished from masking sounds by differences in source location [spatial release from masking (SRM)] and by differences between masker-alone and masker-plus-signal envelopes. This study investigated interactions between those factors in release of masking of 700-Hz tones in an open sound field. Signal and masker sources were colocated in front of the listener, or the signal source was shifted 90° to the side. In Experiment 1, the masker contained a 25-Hz-wide on-signal band plus flanking bands having envelopes that were either mutually uncorrelated or were comodulated. Comodulation masking release (CMR) was largely independent of signal location at a higher masker sound level, but at a lower level CMR was reduced for the lateral signal location. In Experiment 2, a brief signal was positioned at the envelope maximum (peak) or minimum (dip) of a 50-Hz-wide on-signal masker. Masking was released in dip more than in peak conditions only for the 90° signal. Overall, open-field SRM was greater in magnitude than binaural masking release reported in comparable closed-field studies, and envelope-related release was somewhat weaker. Mutual enhancement of masking release by spatial and envelope-related effects tended to increase with increasing masker level.

  10. Cluster randomised controlled trial to examine medical mask use as source control for people with respiratory illness.

    PubMed

    MacIntyre, Chandini Raina; Zhang, Yi; Chughtai, Abrar Ahmad; Seale, Holly; Zhang, Daitao; Chu, Yanhui; Zhang, Haiyan; Rahman, Bayzidur; Wang, Quanyi

    2016-12-30

    Medical masks are commonly used by sick individuals with influenza-like illness (ILI) to prevent spread of infections to others, but clinical efficacy data are absent. Determine whether medical mask use by sick individuals with ILI protects well contacts from related respiratory infections. 6 major hospitals in 2 districts of Beijing, China. Cluster randomised controlled trial. 245 index cases with ILI. Index cases with ILI were randomly allocated to medical mask (n=123) and control arms (n=122). Since 43 index cases in the control arm also used a mask during the study period, an as-treated post hoc analysis was performed by comparing outcomes among household members of index cases who used a mask (mask group) with household members of index cases who did not use a mask (no-mask group). Primary outcomes measured in household members were clinical respiratory illness, ILI and laboratory-confirmed viral respiratory infection. In an intention-to-treat analysis, rates of clinical respiratory illness (relative risk (RR) 0.61, 95% CI 0.18 to 2.13), ILI (RR 0.32, 95% CI 0.03 to 3.13) and laboratory-confirmed viral infections (RR 0.97, 95% CI 0.06 to 15.54) were consistently lower in the mask arm compared with control, although not statistically significant. A post hoc comparison between the mask versus no-mask groups showed a protective effect against clinical respiratory illness, but not against ILI and laboratory-confirmed viral respiratory infections. The study indicates a potential benefit of medical masks for source control, but is limited by small sample size and low secondary attack rates. Larger trials are needed to confirm efficacy of medical masks as source control. ACTRN12613000852752; Results. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  11. Cluster randomised controlled trial to examine medical mask use as source control for people with respiratory illness

    PubMed Central

    MacIntyre, Chandini Raina; Zhang, Yi; Chughtai, Abrar Ahmad; Seale, Holly; Zhang, Daitao; Chu, Yanhui; Zhang, Haiyan; Rahman, Bayzidur; Wang, Quanyi

    2016-01-01

    Rationale Medical masks are commonly used by sick individuals with influenza-like illness (ILI) to prevent spread of infections to others, but clinical efficacy data are absent. Objective Determine whether medical mask use by sick individuals with ILI protects well contacts from related respiratory infections. Setting 6 major hospitals in 2 districts of Beijing, China. Design Cluster randomised controlled trial. Participants 245 index cases with ILI. Intervention Index cases with ILI were randomly allocated to medical mask (n=123) and control arms (n=122). Since 43 index cases in the control arm also used a mask during the study period, an as-treated post hoc analysis was performed by comparing outcomes among household members of index cases who used a mask (mask group) with household members of index cases who did not use a mask (no-mask group). Main outcome measure Primary outcomes measured in household members were clinical respiratory illness, ILI and laboratory-confirmed viral respiratory infection. Results In an intention-to-treat analysis, rates of clinical respiratory illness (relative risk (RR) 0.61, 95% CI 0.18 to 2.13), ILI (RR 0.32, 95% CI 0.03 to 3.13) and laboratory-confirmed viral infections (RR 0.97, 95% CI 0.06 to 15.54) were consistently lower in the mask arm compared with control, although not statistically significant. A post hoc comparison between the mask versus no-mask groups showed a protective effect against clinical respiratory illness, but not against ILI and laboratory-confirmed viral respiratory infections. Conclusions The study indicates a potential benefit of medical masks for source control, but is limited by small sample size and low secondary attack rates. Larger trials are needed to confirm efficacy of medical masks as source control. Trial registration number ACTRN12613000852752; Results. PMID:28039289

  12. EUVL back-insertion layout optimization

    NASA Astrophysics Data System (ADS)

    Civay, D.; Laffosse, E.; Chesneau, A.

    2018-03-01

    Extreme ultraviolet lithography (EUVL) is targeted for front-up insertion at advanced technology nodes but will be evaluated for back insertion at more mature nodes. EUVL can put two or more mask levels back on one mask, depending upon what level(s) in the process insertion occurs. In this paper, layout optimization methods are discussed that can be implemented when EUVL back insertion is implemented. The layout optimizations can be focused on improving yield, reliability or density, depending upon the design needs. The proposed methodology modifies the original two or more colored layers and generates an optimized single color EUVL layout design.

  13. Mask technology for EUV lithography

    NASA Astrophysics Data System (ADS)

    Bujak, M.; Burkhart, Scott C.; Cerjan, Charles J.; Kearney, Patrick A.; Moore, Craig E.; Prisbrey, Shon T.; Sweeney, Donald W.; Tong, William M.; Vernon, Stephen P.; Walton, Christopher C.; Warrick, Abbie L.; Weber, Frank J.; Wedowski, Marco; Wilhelmsen, Karl C.; Bokor, Jeffrey; Jeong, Sungho; Cardinale, Gregory F.; Ray-Chaudhuri, Avijit K.; Stivers, Alan R.; Tejnil, Edita; Yan, Pei-yang; Hector, Scott D.; Nguyen, Khanh B.

    1999-04-01

    Extreme UV Lithography (EUVL) is one of the leading candidates for the next generation lithography, which will decrease critical feature size to below 100 nm within 5 years. EUVL uses 10-14 nm light as envisioned by the EUV Limited Liability Company, a consortium formed by Intel and supported by Motorola and AMD to perform R and D work at three national laboratories. Much work has already taken place, with the first prototypical cameras operational at 13.4 nm using low energy laser plasma EUV light sources to investigate issues including the source, camera, electro- mechanical and system issues, photoresists, and of course the masks. EUV lithograph masks are fundamentally different than conventional photolithographic masks as they are reflective instead of transmissive. EUV light at 13.4 nm is rapidly absorbed by most materials, thus all light transmission within the EUVL system from source to silicon wafer, including EUV reflected from the mask, is performed by multilayer mirrors in vacuum.

  14. Regaining motor control in musician's dystonia by restoring sensorimotor organization.

    PubMed

    Rosenkranz, Karin; Butler, Katherine; Williamon, Aaron; Rothwell, John C

    2009-11-18

    Professional musicians are an excellent model of long-term motor learning effects on structure and function of the sensorimotor system. However, intensive motor skill training has been associated with task-specific deficiency in hand motor control, which has a higher prevalence among musicians (musician's dystonia) than in the general population. Using a transcranial magnetic stimulation paradigm, we previously found an expanded spatial integration of proprioceptive input into the hand motor cortex [sensorimotor organization (SMO)] in healthy musicians. In musician's dystonia, however, this expansion was even larger. Whereas motor skills of musicians are likely to be supported by a spatially expanded SMO, we hypothesized that in musician's dystonia this might have developed too far and now disrupts rather than assists task-specific motor control. If so, motor control should be regained by reversing the excessive reorganization in musician's dystonia. Here, we test this hypothesis and show that a 15 min intervention with proprioceptive input (proprioceptive training) restored SMO in pianists with musician's dystonia to the pattern seen in healthy pianists. Crucially, task-specific motor control improved significantly and objectively as measured with a MIDI (musical instrument digital interface) piano, and the amount of behavioral improvement was significantly correlated to the degree of sensorimotor reorganization. In healthy pianists and nonmusicians, the SMO and motor performance remained essentially unchanged. These findings suggest that the differentiation of SMO in the hand motor cortex and the degree of motor control of intensively practiced tasks are significantly linked and finely balanced. Proprioceptive training restored this balance in musician's dystonia to the behaviorally beneficial level of healthy musicians.

  15. Rotating Modulation Imager for the Orphan Source Search Problem

    DTIC Science & Technology

    2008-01-01

    black mask. If the photon hits an open element it is transmitted and the function M(x) = 1. If the photon hits a closed mask element it is not...photon enters the top mask pair in the third slit, but passes through the second slit on the bottom mask. With a single black mask this is physically...modulation efficiency changes as a function of mask thickness for both tungsten and lead masks. The black line shows how the field of view changes with

  16. Suppression of hedgehog signaling regulates hepatic stellate cell activation and collagen secretion.

    PubMed

    Li, Tao; Leng, Xi-Sheng; Zhu, Ji-Ye; Wang, Gang

    2015-01-01

    Hepatic stellate cells (HSCs) play an important role in liver fibrosis. This study investigates the expression of hedgehog in HSC and the role of hedgehog signaling on activation and collagen secretion of HSC. Liver ex vivo perfusion with collagenase IV and density gradient centrifugation were used to isolate HSC. Expression of hedgehog signaling components Ihh, Smo, Ptc, Gli2 and Gli3 in HSC were detected by RT-PCR. Hedgehog siRNA vectors targeting Ihh, Smo and Gli2 were constructed and transfected into HSC respectively. Suppression of hedgehog signaling were detected by SYBR Green fluorescence quantitative RT-PCR. Effects of hedgehog signaling inhibition on HSC activation and collagen I secretion were analyzed. Hedgehog signaling components Ihh, Smo, Ptc, Gli2 and Gli3 were expressed in HSC. siRNA vectors targeting Ihh, Smo and Gli2 were successfully constructed and decreased target gene expression. Suppression of hedgehog signaling significantly decreased the expression of α-SMA in HSC (P<0.01). Collagen type I secretion of HSC were also significantly decreased (P<0.01). In summary, HSC activation and collagen secretion can be regulated by hedgehog signaling. Hedgehog may play a role in the pathogenesis of liver fibrosis.

  17. Bariatric surgery outcomes in black patients with super morbid obesity: a 1-year postoperative review.

    PubMed

    Onyewu, Samuel C; Ogundimu, Ololade O; Ortega, Gezzer; Bauer, Edward S; Emenari, Chijindu C; Molyneaux, Neh D; Layne, Sylvonne A; Changoor, Navin R; Tapscott, Denia; Tran, Daniel D; Fullum, Terrence M

    2017-01-01

    Super morbid obesity (body mass index [BMI] > 50 kg/m 2 ) is associated with significant comorbidities and is disparagingly prevalent among the black population. There is paucity of data regarding bariatric surgery outcomes among super morbid obese (SMO) blacks. Our aim is to evaluate the reduction in weight and resolution of comorbidities after bariatric surgery among SMO black patients at an urban academic institution. A retrospective review of SMO black patients who underwent bariatric surgery from August 2008 to June 2013 at Howard University Hospital. Outcomes of interest include weight loss, improvement or resolution of hypertension, type 2 diabetes, and hyperlipidemia at 12 months. Eighty-seven patients met our inclusion criteria. Mean preoperative weight and BMI were 347.2 lbs and 56.8 kg/m 2 , respectively. At 12 months, mean weight and BMI were 245.3 lbs and 40.1 kg/m 2 , respectively. There was also significant improvement or resolution of hypertension, type 2 diabetes, and hyperlipidemia. Bariatric surgery may result in significant weight loss and improvement or resolution of comorbidities in SMO black patients. Copyright © 2016. Published by Elsevier Inc.

  18. To repair or not to repair: with FAVOR there is no question

    NASA Astrophysics Data System (ADS)

    Garetto, Anthony; Schulz, Kristian; Tabbone, Gilles; Himmelhaus, Michael; Scheruebl, Thomas

    2016-10-01

    In the mask shop the challenges associated with today's advanced technology nodes, both technical and economic, are becoming increasingly difficult. The constant drive to continue shrinking features means more masks per device, smaller manufacturing tolerances and more complexity along the manufacturing line with respect to the number of manufacturing steps required. Furthermore, the extremely competitive nature of the industry makes it critical for mask shops to optimize asset utilization and processes in order to maximize their competitive advantage and, in the end, profitability. Full maximization of profitability in such a complex and technologically sophisticated environment simply cannot be achieved without the use of smart automation. Smart automation allows productivity to be maximized through better asset utilization and process optimization. Reliability is improved through the minimization of manual interactions leading to fewer human error contributions and a more efficient manufacturing line. In addition to these improvements in productivity and reliability, extra value can be added through the collection and cross-verification of data from multiple sources which provides more information about our products and processes. When it comes to handling mask defects, for instance, the process consists largely of time consuming manual interactions that are error prone and often require quick decisions from operators and engineers who are under pressure. The handling of defects itself is a multiple step process consisting of several iterations of inspection, disposition, repair, review and cleaning steps. Smaller manufacturing tolerances and features with higher complexity contribute to a higher number of defects which must be handled as well as a higher level of complexity. In this paper the recent efforts undertaken by ZEISS to provide solutions which address these challenges, particularly those associated with defectivity, will be presented. From automation of aerial image analysis to the use of data driven decision making to predict and propose the optimized back end of line process flow, productivity and reliability improvements are targeted by smart automation. Additionally the generation of the ideal aerial image from the design and several repair enhancement features offer additional capabilities to improve the efficiency and yield associated with defect handling.

  19. Homophone Dominance Modulates the Phonemic-Masking Effect.

    ERIC Educational Resources Information Center

    Berent, Iris; Van Orden, Guy C.

    2000-01-01

    Finds (1) positive phonemic-masking effects occurred for dominant homophones; (2) null phonemic-masking effects occurred for subordinate homophones; and (3) subordinate homophones were much more likely to be falsely identified as their dominant mate. Suggests the source of these null phonemic-masking is itself a phonology effect. Concludes…

  20. Fully optimized shaped pupils: preparation for a test at the Subaru Telescope

    NASA Astrophysics Data System (ADS)

    Carlotti, Alexis; Kasdin, N. Jeremy; Martinache, Frantz; Vanderbei, Robert J.; Young, Elizabeth J.; Che, George; Groff, Tyler D.; Guyon, Olivier

    2012-09-01

    The SCExAO instrument at the Subaru telescope, mainly based on a PIAA coronagraph can benefit from the addition of a robust and simple shaped pupil coronagraph. New shaped pupils, fully optimized in 2 dimensions, make it possible to design optimal apodizers for arbitrarily complex apertures, for instance on-axis telescopes such as the Subaru telescope. We have designed several masks with inner working angles as small as 2.5 λ / D, and for high-contrast regions with different shapes. Using Princeton University nanofabrication facilities, we have manufactured two masks by photolithography. These masks have been tested in the laboratory, both in Princeton and in the facilities of the National Astronomical Observatory of Japan (NAOJ) in Hilo. The goal of this work is to prepare tests on the sky of a shaped pupil coronagraph in 2012.

  1. Apparatus and method for a light direction sensor

    NASA Technical Reports Server (NTRS)

    Leviton, Douglas B. (Inventor)

    2011-01-01

    The present invention provides a light direction sensor for determining the direction of a light source. The system includes an image sensor; a spacer attached to the image sensor, and a pattern mask attached to said spacer. The pattern mask has a slit pattern that as light passes through the slit pattern it casts a diffraction pattern onto the image sensor. The method operates by receiving a beam of light onto a patterned mask, wherein the patterned mask as a plurality of a slit segments. Then, diffusing the beam of light onto an image sensor and determining the direction of the light source.

  2. An iterative sinogram gap-filling method with object- and scanner-dedicated discrete cosine transform (DCT)-domain filters for high resolution PET scanners.

    PubMed

    Kim, Kwangdon; Lee, Kisung; Lee, Hakjae; Joo, Sungkwan; Kang, Jungwon

    2018-01-01

    We aimed to develop a gap-filling algorithm, in particular the filter mask design method of the algorithm, which optimizes the filter to the imaging object by an adaptive and iterative process, rather than by manual means. Two numerical phantoms (Shepp-Logan and Jaszczak) were used for sinogram generation. The algorithm works iteratively, not only on the gap-filling iteration but also on the mask generation, to identify the object-dedicated low frequency area in the DCT-domain that is to be preserved. We redefine the low frequency preserving region of the filter mask at every gap-filling iteration, and the region verges on the property of the original image in the DCT domain. The previous DCT2 mask for each phantom case had been manually well optimized, and the results show little difference from the reference image and sinogram. We observed little or no difference between the results of the manually optimized DCT2 algorithm and those of the proposed algorithm. The proposed algorithm works well for various types of scanning object and shows results that compare to those of the manually optimized DCT2 algorithm without perfect or full information of the imaging object.

  3. Model-Based Least Squares Reconstruction of Coded Source Neutron Radiographs: Integrating the ORNL HFIR CG1D Source Model

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

    Santos-Villalobos, Hector J; Gregor, Jens; Bingham, Philip R

    2014-01-01

    At the present, neutron sources cannot be fabricated small and powerful enough in order to achieve high resolution radiography while maintaining an adequate flux. One solution is to employ computational imaging techniques such as a Magnified Coded Source Imaging (CSI) system. A coded-mask is placed between the neutron source and the object. The system resolution is increased by reducing the size of the mask holes and the flux is increased by increasing the size of the coded-mask and/or the number of holes. One limitation of such system is that the resolution of current state-of-the-art scintillator-based detectors caps around 50um. Tomore » overcome this challenge, the coded-mask and object are magnified by making the distance from the coded-mask to the object much smaller than the distance from object to detector. In previous work, we have shown via synthetic experiments that our least squares method outperforms other methods in image quality and reconstruction precision because of the modeling of the CSI system components. However, the validation experiments were limited to simplistic neutron sources. In this work, we aim to model the flux distribution of a real neutron source and incorporate such a model in our least squares computational system. We provide a full description of the methodology used to characterize the neutron source and validate the method with synthetic experiments.« less

  4. Laser-assisted electrochemical micromachining of mould cavity on the stainless steel surface

    NASA Astrophysics Data System (ADS)

    Li, Xiaohai; Wang, Shuming; Wang, Dong; Tong, Han

    2018-02-01

    In order to fabricate the micro mould cavities with complex structures on 304 stainless steel, laser-assisted electrochemical micromachining (EMM) based on surface modification by fiber laser masking was studied,and a new device of laser-assisted EMM was developed. Laser marking on the surface of 304 stainless steel can first be realized by fiber laser heating scanning. Through analysis of X ray diffraction analysis (XRD), metal oxide layer with predefined pattern can be formed by laser marking, and phase transformation can also occur on the 304 stainless steel surface, which produce the laser masking layer with corrosion resistance. The stainless steel surface with laser masking layer is subsequently etched by EMM, the laser masking layer severs as the temporary protective layer without relying on lithography mask, the fabrication of formed electrodes is also avoided, so micro pattern cavities can fast be fabricated. The impacts on machining accuracy during EMM with laser masking were discussed to optimize machining parameters, such as machining voltage, electrolyte concentration, duty cycle of pulse power supply and electrode gap size, the typical mould cavities 23μm deep were fabricated under the optimized parameters.

  5. Masks in Imaging Flow Cytometry

    PubMed Central

    Dominical, Venina; Samsel, Leigh; McCoy, J. Philip

    2016-01-01

    Data analysis in imaging flow cytometry incorporates elements of flow cytometry together with other aspects of morphological analysis of images. A crucial early step in this analysis is the creation of a mask to distinguish the portion of the image upon which further examination of specified features can be performed. Default masks are provided by the manufacturer of the imaging flow cytometer but additional custom masks can be created by the individual user for specific applications. Flawed or inaccurate masks can have a substantial negative impact on the overall analysis of a sample, thus great care must be taken to ensure the accuracy of masks. Here we discuss various types of masks and cite examples of their use. Furthermore we provide our insight for how to approach selecting and assessing the optimal mask for a specific analysis. PMID:27461256

  6. Metacontrast masking is processed before grapheme-color synesthesia.

    PubMed

    Bacon, Michael Patrick; Bridgeman, Bruce; Ramachandran, Vilayanur S

    2013-01-01

    We investigated the physiological mechanism of grapheme-color synesthesia using metacontrast masking. A metacontrast target is rendered invisible by a mask that is delayed by about 60 ms; the target and mask do not overlap in space or time. Little masking occurs, however, if the target and mask are simultaneous. This effect must be cortical, because it can be obtained dichoptically. To compare the data for synesthetes and controls, we developed a metacontrast design in which nonsynesthete controls showed weaker dichromatic masking (i.e., the target and mask were in different colors) than monochromatic masking. We accomplished this with an equiluminant target, mask, and background for each observer. If synesthetic color affected metacontrast, synesthetes should show monochromatic masking more similar to the weak dichromatic masking among controls, because synesthetes could add their synesthetic color to the monochromatic condition. The target-mask pairs used for each synesthete were graphemes that elicited strong synesthetic colors. We found stronger monochromatic than dichromatic U-shaped metacontrast for both synesthetes and controls, with optimal masking at an asynchrony of 66 ms. The difference in performance between the monochromatic and dichromatic conditions in the synesthetes indicates that synesthesia occurs at a later processing stage than does metacontrast masking.

  7. Revisiting adoption of high transmission PSM: pros, cons and path forward

    NASA Astrophysics Data System (ADS)

    Ma, Z. Mark; McDonald, Steve; Progler, Chris

    2009-12-01

    High transmission attenuated phase shift masks (Hi-T PSM) have been successfully applied in volume manufacturing for certain memory devices. Moreover, numerous studies have shown the potential benefits of Hi-T PSM for specific lithography applications. In this paper, the potential for extending Hi-T PSM to logic devices, is revisited with an emphasis on understanding layout, transmission, and manufacturing of Hi-T PSM versus traditional 6% embedded attenuated phase shift mask (EAPSM). Simulations on various layouts show Hi-T PSM has advantage over EAPSM in low duty cycle line patterns and high duty cycle space patterns. The overall process window can be enhanced when Hi- T PSM is combined with optimized optical proximity correction (OPC), sub-resolution assist features (SRAF), and source illumination. Therefore, Hi-T PSM may be a viable and lower cost alternative to other complex resolution enhancement technology (RET) approaches. Aerial image measurement system (AIMS) results on test masks, based on an inverse lithography technology (ILT) generated layout, confirm the simulation results. New advancement in high transmission blanks also make low topography Hi-T PSM a reality, which can minimize scattering effects in high NA lithography.

  8. Improving the CD linearity and proximity performance of photomasks written on the Sigma7500-II DUV laser writer through embedded OPC

    NASA Astrophysics Data System (ADS)

    Österberg, Anders; Ivansen, Lars; Beyerl, Angela; Newman, Tom; Bowhill, Amanda; Sahouria, Emile; Schulze, Steffen

    2007-10-01

    Optical proximity correction (OPC) is widely used in wafer lithography to produce a printed image that best matches the design intent while optimizing CD control. OPC software applies corrections to the mask pattern data, but in general it does not compensate for the mask writer and mask process characteristics. The Sigma7500-II deep-UV laser mask writer projects the image of a programmable spatial light modulator (SLM) using partially coherent optics similar to wafer steppers, and the optical proximity effects of the mask writer are in principle correctable with established OPC methods. To enhance mask patterning, an embedded OPC function, LinearityEqualize TM, has been developed for the Sigma7500- II that is transparent to the user and which does not degrade mask throughput. It employs a Calibre TM rule-based OPC engine from Mentor Graphics, selected for the computational speed necessary for mask run-time execution. A multinode cluster computer applies optimized table-based CD corrections to polygonized pattern data that is then fractured into an internal writer format for subsequent data processing. This embedded proximity correction flattens the linearity behavior for all linewidths and pitches, which targets to improve the CD uniformity on production photomasks. Printing results show that the CD linearity is reduced to below 5 nm for linewidths down to 200 nm, both for clear and dark and for isolated and dense features, and that sub-resolution assist features (SRAF) are reliably printed down to 120 nm. This reduction of proximity effects for main mask features and the extension of the practical resolution for SRAFs expands the application space of DUV laser mask writing.

  9. An improved principal component analysis based region matching method for fringe direction estimation

    NASA Astrophysics Data System (ADS)

    He, A.; Quan, C.

    2018-04-01

    The principal component analysis (PCA) and region matching combined method is effective for fringe direction estimation. However, its mask construction algorithm for region matching fails in some circumstances, and the algorithm for conversion of orientation to direction in mask areas is computationally-heavy and non-optimized. We propose an improved PCA based region matching method for the fringe direction estimation, which includes an improved and robust mask construction scheme, and a fast and optimized orientation-direction conversion algorithm for the mask areas. Along with the estimated fringe direction map, filtered fringe pattern by automatic selective reconstruction modification and enhanced fast empirical mode decomposition (ASRm-EFEMD) is used for Hilbert spiral transform (HST) to demodulate the phase. Subsequently, windowed Fourier ridge (WFR) method is used for the refinement of the phase. The robustness and effectiveness of proposed method are demonstrated by both simulated and experimental fringe patterns.

  10. Combinatorial algorithms for design of DNA arrays.

    PubMed

    Hannenhalli, Sridhar; Hubell, Earl; Lipshutz, Robert; Pevzner, Pavel A

    2002-01-01

    Optimal design of DNA arrays requires the development of algorithms with two-fold goals: reducing the effects caused by unintended illumination (border length minimization problem) and reducing the complexity of masks (mask decomposition problem). We describe algorithms that reduce the number of rectangles in mask decomposition by 20-30% as compared to a standard array design under the assumption that the arrangement of oligonucleotides on the array is fixed. This algorithm produces provably optimal solution for all studied real instances of array design. We also address the difficult problem of finding an arrangement which minimizes the border length and come up with a new idea of threading that significantly reduces the border length as compared to standard designs.

  11. Medical students as teachers at CoSMO, Columbia University's student-run clinic: a pilot study and literature review.

    PubMed

    Hamso, Magni; Ramsdell, Amanda; Balmer, Dorene; Boquin, Cyrus

    2012-01-01

    Although medical students are expected to teach as soon as they begin residency, medical schools have just recently begun adding teacher training to their curricula. Student-run clinics (SRCs) may provide opportunities in clinical teaching before residency. The aim of this pilot study was to examine students' experiences in clinical teaching at Columbia Student Medical Outreach (CoSMO), Columbia University's SRC, during the 2009-2010 school year. A mixed-methods approach was used. Data included closed and open-ended surveys (n = 34), combined interviews with preclinical and clinical student pairs (n = 5), individual interviews (n = 10), and focus groups (n = 3). The transcripts were analyzed using the principles of grounded theory. Many students had their first clinical teaching experience while volunteering at CoSMO. Clinical students' ability to teach affected the quality of the learning experience for their preclinical peers. Preclinical students who asked questions and engaged in patient care challenged their clinical peers to balance teaching with patient care. Clinical students began to see themselves as teachers while volunteering at CoSMO. The practical experiences in clinical teaching that students have at SRCs can supplement classroom-based trainings. Medical schools might revisit their SRCs as places for exposure to clinical teaching.

  12. EQ-10 electrodeless Z-pinch EUV source for metrology applications

    NASA Astrophysics Data System (ADS)

    Gustafson, Deborah; Horne, Stephen F.; Partlow, Matthew J.; Besen, Matthew M.; Smith, Donald K.; Blackborow, Paul A.

    2011-11-01

    With EUV Lithography systems shipping, the requirements for highly reliable EUV sources for mask inspection and resist outgassing are becoming better defined, and more urgent. The sources needed for metrology applications are very different than that needed for lithography; brightness (not power) is the key requirement. Suppliers for HVM EUV sources have all resources working on high power and have not entered the smaller market for metrology. Energetiq Technology has been shipping the EQ-10 Electrodeless Z-pinchTM light source since 19951. The source is currently being used for metrology, mask inspection, and resist development2-4. These applications require especially stable performance in both output power and plasma size and position. Over the last 6 years Energetiq has made many source modifications which have included better thermal management to increase the brightness and power of the source. We now have introduced a new source that will meet requirements of some of the mask metrology first generation tools; this source will be reviewed.

  13. Improved techniques reduce face mask leak during simulated neonatal resuscitation: study 2.

    PubMed

    Wood, Fiona E; Morley, Colin J; Dawson, Jennifer A; Kamlin, C Omar F; Owen, Louise S; Donath, Susan; Davis, Peter G

    2008-05-01

    Techniques of positioning and holding neonatal face masks vary. Studies have shown that leak at the face mask is common and often substantial irrespective of operator experience. (1) To identify a technique for face mask placement and hold which will minimise mask leak. (2) To investigate the effect of written instruction and demonstration of the identified technique on mask leak for two round face masks. Three experienced neonatologists compared methods of placing and holding face masks to minimise the leak for Fisher & Paykel 60 mm and Laerdal size 0/1 masks. 50 clinical staff gave positive pressure ventilation to a modified manikin designed to measure leak at the face mask. They were provided with written instructions on how to position and hold each mask and then received a demonstration. Face mask leak was measured after each teaching intervention. A technique of positioning and holding the face masks was identified which minimised leak. The mean (SD) mask leaks before instruction, after instruction and after demonstration were 55% (31), 49% (30), 33% (26) for the Laerdal mask and 57% (25), 47% (28), 32% (30) for the Fisher & Paykel mask. There was no significant difference in mask leak between the two masks. Written instruction alone reduced leak by 8.8% (CI 1.4% to 16.2%) for either mask; when combined with a demonstration mask leak was reduced by 24.1% (CI 16.4% to 31.8%). Written instruction and demonstration of the identified optimal technique resulted in significantly reduced face mask leak.

  14. Dead space variability of face masks for valved holding chambers.

    PubMed

    Amirav, Israel; Newhouse, Michael T

    2008-03-01

    Valved holding chambers with masks are commonly used to deliver inhaled medications to young children with asthma. Optimal mask properties such as their dead space volume have received little attention. The smaller the mask the more likely it is that a greater proportion of the dose in the VHC will be inhaled with each breath, thus speeding VHC emptying and improving overall aerosol delivery efficiency and dose. Masks may have different DSV and thus different performance. To compare both physical dead space and functional dead space of different face masks under various applied pressures. The DSV of three commonly used face masks of VHCs was measured by water displacement both under various pressures (to simulate real-life application, dynamic DSV) and under no pressure (static DSV). There was a great variability of both static and dynamic dead space among various face mask for VHCs, which is probably related to their flexibility. Different masks have different DSV characteristics. This variability should be taken into account when comparing the clinical efficacy of various VHCs.

  15. Dual-sided coded-aperture imager

    DOEpatents

    Ziock, Klaus-Peter [Clinton, TN

    2009-09-22

    In a vehicle, a single detector plane simultaneously measures radiation coming through two coded-aperture masks, one on either side of the detector. To determine which side of the vehicle a source is, the two shadow masks are inverses of each other, i.e., one is a mask and the other is the anti-mask. All of the data that is collected is processed through two versions of an image reconstruction algorithm. One treats the data as if it were obtained through the mask, the other as though the data is obtained through the anti-mask.

  16. A Counter-Social Movement Approach to Deconstructing Daesh

    DTIC Science & Technology

    alternative, the US military could view Daesh as a transnational social movement organization (SMO), and by doing so, planners could develop a more effective... social movement theory (SMT) to determine lines of effort (LOE) against which US military forces could best apply resources to counteract the SMO. This... study is divided into four sections. The first section constitutes an overview of SMT as a form of contentious politics. The second section presents a

  17. Crevice Corrosion Behavior of 45 Molybdenum-Containing Stainless Steels in Seawater.

    DTIC Science & Technology

    1981-12-01

    Armco, Avesta Jernverks, Cabot, Carpenter Technology, Crucible, Eastern, Firth-Brown, Huntington, Jessup, Langley Alloys, and Uddeholm. 16...Department of Energy, Report ANL/OTEC-BCM-022. 7. Wallen, B., and M. Liljas, " Avesta 254 SMO - A New, High Molybdenum Stainless Steel," presented at NKM8...1977).; 11. Wallen, B., " Avesta 254 SMO - A Stainless Steel for Seawater Service," presented at the Advanced Stainless Steels for Turbine Condensors

  18. Reflective Occultation Mask for Evaluation of Occulter Designs for Planet Finding

    NASA Technical Reports Server (NTRS)

    Hagopian, John; Lyon, Richard; Shiri, Shahram; Roman, Patrick

    2011-01-01

    Advanced formation flying occulter designs utilize a large occulter mask flying in formation with an imaging telescope to block and null starlight to allow imaging of faint planets in exosolar systems. A paper describes the utilization of subscale reflective occultation masks to evaluate formation flying occulter designs. The use of a reflective mask allows mounting of the occulter by conventional means and simplifies the test configuration. The innovation alters the test set-up to allow mounting of the mask using standard techniques to eliminate the problems associated with a standard configuration. The modified configuration uses a reflective set-up whereby the star simulator reflects off of a reflective occulting mask and into an evaluation telescope. Since the mask is sized to capture all rays required for the imaging test, it can be mounted directly to a supporting fixture without interfering with the beam. Functionally, the reflective occultation mask reflects light from the star simulator instead of transmitting it, with a highly absorptive carbon nanotube layer simulating the occulter blocking mask. A subscale telescope images the star source and companion dim source that represents a planet. The primary advantage of this is that the occulter can be mounted conventionally instead of using diffractive wires or magnetic levitation.

  19. 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 contamination was identified as the key source of particle induced repeater defects.

  20. Vectorial mask optimization methods for robust optical lithography

    NASA Astrophysics Data System (ADS)

    Ma, Xu; Li, Yanqiu; Guo, Xuejia; Dong, Lisong; Arce, Gonzalo R.

    2012-10-01

    Continuous shrinkage of critical dimension in an integrated circuit impels the development of resolution enhancement techniques for low k1 lithography. Recently, several pixelated optical proximity correction (OPC) and phase-shifting mask (PSM) approaches were developed under scalar imaging models to account for the process variations. However, the lithography systems with larger-NA (NA>0.6) are predominant for current technology nodes, rendering the scalar models inadequate to describe the vector nature of the electromagnetic field that propagates through the optical lithography system. In addition, OPC and PSM algorithms based on scalar models can compensate for wavefront aberrations, but are incapable of mitigating polarization aberrations in practical lithography systems, which can only be dealt with under the vector model. To this end, we focus on developing robust pixelated gradient-based OPC and PSM optimization algorithms aimed at canceling defocus, dose variation, wavefront and polarization aberrations under a vector model. First, an integrative and analytic vector imaging model is applied to formulate the optimization problem, where the effects of process variations are explicitly incorporated in the optimization framework. A steepest descent algorithm is then used to iteratively optimize the mask patterns. Simulations show that the proposed algorithms can effectively improve the process windows of the optical lithography systems.

  1. Design architecture of double spiral interdigitated electrode with back gate electrode for biosensor application

    NASA Astrophysics Data System (ADS)

    Fathil, M. F. M.; Arshad, M. K. Md.; Hashim, U.; Ruslinda, A. R.; Gopinath, Subash C. B.; M. Nuzaihan M., N.; Ayub, R. M.; Adzhri, R.; Zaki, M.; Azman, A. H.

    2016-07-01

    This paper presents the preparation method of photolithography chrome mask design used in fabrication process of double spiral interdigitated electrode with back gate biasing based biosensor. By learning the fabrication process flow of the biosensor, the chrome masks are designed through drawing using the AutoCAD software. The overall width and length of the device is optimized at 7.0 mm and 10.0 mm, respectively. Fabrication processes of the biosensor required three chrome masks, which included back gate opening, spiral IDE formation, and passivation area formation. The complete chrome masks design will be sent for chrome mask fabrication and for future use in biosensor fabrication.

  2. In-die photomask registration and overlay metrology with PROVE using 2D correlation methods

    NASA Astrophysics Data System (ADS)

    Seidel, D.; Arnz, M.; Beyer, D.

    2011-11-01

    According to the ITRS roadmap, semiconductor industry drives the 193nm lithography to its limits, using techniques like double exposure, double patterning, mask-source optimization and inverse lithography. For photomask metrology this translates to full in-die measurement capability for registration and critical dimension together with challenging specifications for repeatability and accuracy. Especially, overlay becomes more and more critical and must be ensured on every die. For this, Carl Zeiss SMS has developed the next generation photomask registration and overlay metrology tool PROVE® which serves the 32nm node and below and which is already well established in the market. PROVE® features highly stable hardware components for the stage and environmental control. To ensure in-die measurement capability, sophisticated image analysis methods based on 2D correlations have been developed. In this paper we demonstrate the in-die capability of PROVE® and present corresponding measurement results for shortterm and long-term measurements as well as the attainable accuracy for feature sizes down to 85nm using different illumination modes and mask types. Standard measurement methods based on threshold criteria are compared with the new 2D correlation methods to demonstrate the performance gain of the latter. In addition, mask-to-mask overlay results of typical box-in-frame structures down to 200nm feature size are presented. It is shown, that from overlay measurements a reproducibility budget can be derived that takes into account stage, image analysis and global effects like mask loading and environmental control. The parts of the budget are quantified from measurement results to identify critical error contributions and to focus on the corresponding improvement strategies.

  3. Lithographic performance comparison with various RET for 45-nm node with hyper NA

    NASA Astrophysics Data System (ADS)

    Adachi, Takashi; Inazuki, Yuichi; Sutou, Takanori; Kitahata, Yasuhisa; Morikawa, Yasutaka; Toyama, Nobuhito; Mohri, Hiroshi; Hayashi, Naoya

    2006-05-01

    In order to realize 45 nm node lithography, strong resolution enhancement technology (RET) and water immersion will be needed. In this research, we discussed about various RET performance comparison for 45 nm node using 3D rigorous simulation. As a candidate, we chose binary mask (BIN), several kinds of attenuated phase-shifting mask (att-PSM) and chrome-less phase-shifting lithography mask (CPL). The printing performance was evaluated and compared for each RET options, after the optimizing illumination conditions, mask structure and optical proximity correction (OPC). The evaluation items of printing performance were CD-DOF, contrast-DOF, conventional ED-window and MEEF, etc. It's expected that effect of mask 3D topography becomes important at 45 nm node, so we argued about not only the case of ideal structures, but also the mask topography error effects. Several kinds of mask topography error were evaluated and we confirmed how these errors affect to printing performance.

  4. Innovative method to suppress local geometry distortions for fabrication of interdigitated electrode arrays with nano gaps

    NASA Astrophysics Data System (ADS)

    Partel, S.; Urban, G.

    2016-03-01

    In this paper we present a method to optimize the lithography process for the fabrication of interdigitated electrode arrays (IDA) for a lift-off free electrochemical biosensor. The biosensor is based on amperometric method to allow a signal amplification by redox cycling. We already demonstrated a method to fabricate IDAs with nano gaps with conventional mask aligner lithography and two subsequent deposition processes. By decreasing the distance down to the nanometer range the linewidth variation is becoming the most critical factor and can result in a short circuit of the electrodes. Therefore, the light propagation and the resist pattern of the mask aligner lithography process are simulated to optimize the lithography process. To optimize the outer finger structure assistant features (AsFe) were introduced. The AsFe allow an optimization of the intensity distribution at the electrode fingers. Hence, the periodicity is expanded and the outer structure of the IDA is practically a part of the periodic array. The better CD uniformity can be obtained by adding three assistant features which generate an equal intensity distributions for the complete finger pattern. Considering a mask optimization of the outer structures would also be feasible. However, due to the strong impact of the gap between mask and wafer at contact lithography it is not practicable. The better choice is to create the same intensity distribution for all finger structures. With the introduction of the assistant features large areas with electrode gap sizes in the sub 100 nm region are demonstrated.

  5. JWST-MIRI spectrometer main optics design and main results

    NASA Astrophysics Data System (ADS)

    Navarro, Ramón; Schoenmaker, Ton; Kroes, Gabby; Oudenhuysen, Ad; Jager, Rieks; Venema, Lars

    2017-11-01

    MIRI ('Mid InfraRed Instrument') is the combined imager and integral field spectrometer for the 5-29 micron wavelength range under development for the James Webb Space Telescope JWST. The flight acceptance tests of the Spectrometer Main Optics flight models (SMO), part of the MIRI spectrometer, are completed in the summer of 2008 and the system is delivered to the MIRI-JWST consortium. The two SMO arms contain 14 mirrors and form the MIRI optical system together with 12 selectable gratings on grating wheels. The entire system operates at a temperature of 7 Kelvin and is designed on the basis of a 'no adjustments' philosophy. This means that the optical alignment precision depends strongly on the design, tolerance analysis and detailed knowledge of the manufacturing process. Because in principle no corrections are needed after assembly, continuous tracking of the alignment performance during the design and manufacturing phases is important. The flight hardware is inspected with respect to performance parameters like alignment and image quality. The stability of these parameters is investigated after exposure to various vibration levels and successive cryogenic cool downs. This paper describes the philosophy behind the acceptance tests, the chosen test strategy and reports the results of these tests. In addition the paper covers the design of the optical test setup, focusing on the simulation of the optical interfaces of the SMO. Also the relation to the SMO qualification and verification program is addressed.

  6. Efficacy of Asparaginase Erwinia chrysanthemi With and Without Temozolomide Against Glioma Cells and Intracranial Mouse Medulloblastoma.

    PubMed

    Sanghez, Valentina; Chen, Mengqing; Li, Shan; Chou, Tsui-Fen; Iacovino, Michelina; Lin, Henry J; Lasky, Joseph L; Panosyan, Eduard H

    2018-05-01

    Anti-metabolites are less-myelosuppressive than DNA-damaging anticancer drugs and may be useful against brain tumors. We evaluated the asparagine/glutamine-deaminating agent Erwinaze with/without temozolomide against brain tumor cells and mouse medulloblastomas. Erwinaze treatment of cell lines and neurospheres led to dose-dependent reductions of cells (reversible by L-glutamine), with half maximal inhibitory concentrations (IC 50 s) of 0.12->10 IU/ml. Erwinaze at <1 IU/ml reduced temozolomide IC 50 s by 3.6- to 13-fold (300-1,200 μM to 40-330 μM). Seven-week-old SMO/SMO mice treated with Erwinaze (regardless of temozolomide treatment) had better survival 11 weeks post-therapy, compared to those not treated with Erwinaze (81.25% vs. 46.15, p=0.08). Temozolomide-treated mice developed 10% weight loss, impairing survival. All 16 mice treated with temozolomide (regardless of Erwinaze treatment) succumbed by 40-weeks of age, whereas 5/8 animals treated with Erwinaze alone and 2/6 controls survived (p=0.035). Erwinaze enhances cytotoxicity of temozolomide in vitro, and improves survival in SMO/SMO mice, likely by reducing cerebrospinal fluid glutamine. Temozolomide-associated toxicity prevented demonstration of any potential combinatorial advantage with Erwinaze in vivo. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  7. A New Sample Transect through the Sierra Madre Occidental Silicic Large Igneous Province in Southern Chihuahua State, Mexico: First Stratigraphic, Petrologic, and Geochemical Results

    NASA Astrophysics Data System (ADS)

    Andrews, G. D.; Davila Harris, P.; Brown, S. R.; Anderson, L.; Moreno, N.

    2014-12-01

    We completed a field sampling transect across the northern Sierra Madre Occidental silicic large igneous province (SMO) in December 2013. Here we present the first stratigraphic, petrological, and geochemical data from the transect between Hidalgo del Parral and Guadalupe y Calvo, Chihuahua, Mexico. This is the first new transect across the SMO in 25 years and the only one between existing NE - SW transects at Chihuahua - Hermosillo and Durango - Mazatlan. The 245 km-long transect along Mexican Highway 24 crosses the boundary between the extended (Basin and Range) and non-extended (Sierra Madre Occidental plateau) parts of the SMO, and allows sampling of previously undescribed Oligocene (?) - early Miocene (?) rhyolitic ignimbrites and lavas, and occasional post-rhyolite, Miocene (?) SCORBA basaltic andesite lavas. 54 samples of rhyolitic ignimbrites (40) and lavas (7), and basaltic andesite lavas (7) were sampled along the transect, including 8 canyon sections with more than one unit. The ignimbrites are overwhelming rhyodacitic (plagioclase and hornblende or biotite phyric) or rhyolitic (quartz (+/- sanidine) in additon to plagioclase and hornblende or biotite phyric) and sparsely to highly phyric. Preliminary petrographic (phenocryst abundances) and geochemical (major and trace element) will be presented and compared to existing data from elsewhere in the SMO. Future work will include U-Pb zircon dating and whole rock and in-zircon radiogenic isotopes analyses.

  8. MicroRNA-1271 inhibits proliferation and promotes apoptosis of multiple myeloma cells through inhibiting smoothened-mediated Hedgehog signaling pathway.

    PubMed

    Xu, Zhengwei; Huang, Chen; Hao, Dingjun

    2017-02-01

    MicroRNAs (miRNAs) have emerged as important regulators in multiple myeloma (MM). miR-1271 is a tumor suppressor in many cancer types. However, the biological role of miR-1271 in MM remains unclear. In the present study, we elucidated the biological role of miR-1271 in MM. Results showed that miR-1271 was significantly decreased in primary MM cells from MM patients and MM cell lines. Overexpression of miR-1271 inhibited proliferation and promoted apoptosis of MM cells. Conversely, suppression of miR-1271 showed the opposite effect. Bioinformatics algorithm analysis predicted that smoothened (SMO), the activator of Hedgehog (HH) signaling pathway, was a direct target of miR-1271 that was experimentally verified by a dual-luciferase reporter assay. Furthermore, overexpression of miR-1271 inhibited SMO expression and HH signaling pathway. Conversely, the restoration of SMO expression markedly abolished the effect of miR-1271 overexpression on cell proliferation, apoptosis and HH signaling pathway in MM cells. Taken together, the present study suggests that miR-1271 functions as a tumor suppressor that inhibits proliferation and promotes apoptosis of MM cells through inhibiting SMO-mediated HH signaling pathway. This finding implies that miR-1271 is a potential therapeutic target for the treatment of MM.

  9. Three-dimensional polarization marked multiple-QR code encryption by optimizing a single vectorial beam

    NASA Astrophysics Data System (ADS)

    Lin, Chao; Shen, Xueju; Hua, Binbin; Wang, Zhisong

    2015-10-01

    We demonstrate the feasibility of three dimensional (3D) polarization multiplexing by optimizing a single vectorial beam using a multiple-signal window multiple-plane (MSW-MP) phase retrieval algorithm. Original messages represented with multiple quick response (QR) codes are first partitioned into a series of subblocks. Then, each subblock is marked with a specific polarization state and randomly distributed in 3D space with both longitudinal and transversal adjustable freedoms. A generalized 3D polarization mapping protocol is established to generate a 3D polarization key. Finally, multiple-QR code is encrypted into one phase only mask and one polarization only mask based on the modified Gerchberg-Saxton (GS) algorithm. We take the polarization mask as the cyphertext and the phase only mask as additional dimension of key. Only when both the phase key and 3D polarization key are correct, original messages can be recovered. We verify our proposal with both simulation and experiment evidences.

  10. In collaboration with mask suppliers for change management enhancement

    NASA Astrophysics Data System (ADS)

    Deng, Erwin; Lee, Chun Der; Lee, Rachel

    2013-06-01

    For those wafer fabs that have no their own maskshops, the main target of mask quality department is to gain stable mask quality performance through effective supplier management, and therefore achieves competitive business results. After dealing with lots of mask data preparation (MDP) quality problems with suppliers, we have found that incomplete change management procedures are one of major sources that induce incorrect mask data for writing. This article will share our experience in how to enhance change management flows with mask suppliers together and will also show the utility after a series of flow improvement actions.

  11. Improving global CD uniformity by optimizing post-exposure bake and develop sequences

    NASA Astrophysics Data System (ADS)

    Osborne, Stephen P.; Mueller, Mark; Lem, Homer; Reyland, David; Baik, KiHo

    2003-12-01

    Improvements in the final uniformity of masks can be shrouded by error contributions from many sources. The final Global CD Uniformity (GCDU) of a mask is degraded by individual contributions of the writing tool, the Post Applied Bake (PAB), the Post Exposure Bake (PEB), the Develop sequence and the Etch step. Final global uniformity will improve by isolating and minimizing the variability of the PEB and Develop. We achieved this de-coupling of the PEB and Develop process from the whole process stream by using "dark loss" which is the loss of unexposed resist during the develop process. We confirmed a correspondence between Angstroms of dark loss and nanometer sized deviations in the chrome CD. A plate with a distinctive dark loss pattern was related to a nearly identical pattern in the chrome CD. This pattern was verified to have originated during the PEB process and displayed a [Δ(Final CD)/Δ(Dark Loss)] ratio of 6 for TOK REAP200 resist. Previous papers have reported a sensitive linkage between Angstroms of dark loss and nanometers in the final uniformity of the written plate. These initial studies reported using this method to improve the PAB of resists for greater uniformity of sensitivity and contrast. Similarly, this paper demonstrates an outstanding optimization of PEB and Develop processes.

  12. Comparison of cloud optical depth and cloud mask applying BRDF model-based background surface reflectance

    NASA Astrophysics Data System (ADS)

    Kim, H. W.; Yeom, J. M.; Woo, S. H.

    2017-12-01

    Over the thin cloud region, satellite can simultaneously detect the reflectance from thin clouds and land surface. Since the mixed reflectance is not the exact cloud information, the background surface reflectance should be eliminated to accurately distinguish thin cloud such as cirrus. In the previous research, Kim et al (2017) was developed the cloud masking algorithm using the Geostationary Ocean Color Imager (GOCI), which is one of significant instruments for Communication, Ocean, and Meteorology Satellite (COMS). Although GOCI has 8 spectral channels including visible and near infra-red spectral ranges, the cloud masking has quantitatively reasonable result when comparing with MODIS cloud mask (Collection 6 MYD35). Especially, we noticed that this cloud masking algorithm is more specialized in thin cloud detections through the validation with Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data. Because this cloud masking method was concentrated on eliminating background surface effects from the top-of-atmosphere (TOA) reflectance. Applying the difference between TOA reflectance and the bi-directional reflectance distribution function (BRDF) model-based background surface reflectance, cloud areas both thick cloud and thin cloud can be discriminated without infra-red channels which were mostly used for detecting clouds. Moreover, when the cloud mask result was utilized as the input data when simulating BRDF model and the optimized BRDF model-based surface reflectance was used for the optimized cloud masking, the probability of detection (POD) has higher value than POD of the original cloud mask. In this study, we examine the correlation between cloud optical depth (COD) and its cloud mask result. Cloud optical depths mostly depend on the cloud thickness, the characteristic of contents, and the size of cloud contents. COD ranges from less than 0.1 for thin clouds to over 1000 for the huge cumulus due to scattering by droplets. With the cloud optical depth of CALIPSO, the cloud masking result can be more improved since we can figure out how deep cloud is. To validate the cloud mask and the correlation result, the atmospheric retrieval will be computed to compare the difference between TOA reflectance and the simulated surface reflectance.

  13. Ecosystem service trade-offs and their influencing factors: A case study in the Loess Plateau of China.

    PubMed

    Feng, Qiang; Zhao, Wenwu; Fu, Bojie; Ding, Jingyi; Wang, Shuai

    2017-12-31

    Soil erosion control (SEC), carbon sequestration (CAS), and soil moisture (SMO) strongly interact in the semi-arid Loess Plateau. Since SMO has supportive effects on SEC and CAS, it can be considered as ecosystem service (ES), and there is an immediate need to coordinate the relationships among these ecosystem services (ESs) to promote the sustainability of vegetation recovery. In this study, we quantified the ESs, ES trade-offs, and the environmental factors in 151 sample plots in the Ansai watershed, and we used a redundancy analysis (RDA) to clarify the effects of environmental factors on these ESs and their trade-offs. The results were as follows: (1) the general trend in the SEC of vegetation types was Robinia pseudoacacia (CH)>native grass (NG)>small arbor (ST)>Hippophae rhamnoides (SJ)>artificial grass (AG)>Caragana korshinskii (NT)>apple orchard (GY)>crop (CP); the CAS trend was CH>SJ>NT>AG>CP>ST>GY>NG; and the SMO trend was CP>NG>GY>AG>SJ>ST>CH>NT. (2) For SEC-SMO trade-offs, the influence of vegetation type, altitude, silt and sand composition was dominant. The arrangement of NG, AG, and SJ could decrease the extent of the trade-offs. (3) For CAS-SMO trade-offs, vegetation coverage and types were the dominant factors, but the effects were not complex. The extent of these trade-offs was lowest for NT, and that for SJ was the second lowest. (4) Considering the relationships among the three ESs, SJ was the most appropriate afforestation plant. Combing the vegetation types, slope position, slope gradient, and soil properties could regulate these ES relationships. The dominant factors influencing ES trade-offs varied among the different soil layers, so we must consider the corresponding influencing factors to regulate ESs. Moreover, manual management measures were also important for coordinating the ES relationships. Our research provides a better understanding of the mechanisms influencing the relationships among ESs. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Validating the WHO maternal near miss tool: comparing high- and low-resource settings.

    PubMed

    Witteveen, Tom; Bezstarosti, Hans; de Koning, Ilona; Nelissen, Ellen; Bloemenkamp, Kitty W; van Roosmalen, Jos; van den Akker, Thomas

    2017-06-19

    WHO proposed the WHO Maternal Near Miss (MNM) tool, classifying women according to several (potentially) life-threatening conditions, to monitor and improve quality of obstetric care. The objective of this study is to analyse merged data of one high- and two low-resource settings where this tool was applied and test whether the tool may be suitable for comparing severe maternal outcome (SMO) between these settings. Using three cohort studies that included SMO cases, during two-year time frames in the Netherlands, Tanzania and Malawi we reassessed all SMO cases (as defined by the original studies) with the WHO MNM tool (five disease-, four intervention- and seven organ dysfunction-based criteria). Main outcome measures were prevalence of MNM criteria and case fatality rates (CFR). A total of 3172 women were studied; 2538 (80.0%) from the Netherlands, 248 (7.8%) from Tanzania and 386 (12.2%) from Malawi. Total SMO detection was 2767 (87.2%) for disease-based criteria, 2504 (78.9%) for intervention-based criteria and 1211 (38.2%) for organ dysfunction-based criteria. Including every woman who received ≥1 unit of blood in low-resource settings as life-threatening, as defined by organ dysfunction criteria, led to more equally distributed populations. In one third of all Dutch and Malawian maternal death cases, organ dysfunction criteria could not be identified from medical records. Applying solely organ dysfunction-based criteria may lead to underreporting of SMO. Therefore, a tool based on defining MNM only upon establishing organ failure is of limited use for comparing settings with varying resources. In low-resource settings, lowering the threshold of transfused units of blood leads to a higher detection rate of MNM. We recommend refined disease-based criteria, accompanied by a limited set of intervention- and organ dysfunction-based criteria to set a measure of severity.

  15. Accelerator test of the coded aperture mask technique for gamma-ray astronomy

    NASA Technical Reports Server (NTRS)

    Jenkins, T. L.; Frye, G. M., Jr.; Owens, A.; Carter, J. N.; Ramsden, D.

    1982-01-01

    A prototype gamma-ray telescope employing the coded aperture mask technique has been constructed and its response to a point source of 20 MeV gamma-rays has been measured. The point spread function is approximately a Gaussian with a standard deviation of 12 arc minutes. This resolution is consistent with the cell size of the mask used and the spatial resolution of the detector. In the context of the present experiment, the error radius of the source position (90 percent confidence level) is 6.1 arc minutes.

  16. Rigorous ILT optimization for advanced patterning and design-process co-optimization

    NASA Astrophysics Data System (ADS)

    Selinidis, Kosta; Kuechler, Bernd; Cai, Howard; Braam, Kyle; Hoppe, Wolfgang; Domnenko, Vitaly; Poonawala, Amyn; Xiao, Guangming

    2018-03-01

    Despite the large difficulties involved in extending 193i multiple patterning and the slow ramp of EUV lithography to full manufacturing readiness, the pace of development for new technology node variations has been accelerating. Multiple new variations of new and existing technology nodes have been introduced for a range of device applications; each variation with at least a few new process integration methods, layout constructs and/or design rules. This had led to a strong increase in the demand for predictive technology tools which can be used to quickly guide important patterning and design co-optimization decisions. In this paper, we introduce a novel hybrid predictive patterning method combining two patterning technologies which have each individually been widely used for process tuning, mask correction and process-design cooptimization. These technologies are rigorous lithography simulation and inverse lithography technology (ILT). Rigorous lithography simulation has been extensively used for process development/tuning, lithography tool user setup, photoresist hot-spot detection, photoresist-etch interaction analysis, lithography-TCAD interactions/sensitivities, source optimization and basic lithography design rule exploration. ILT has been extensively used in a range of lithographic areas including logic hot-spot fixing, memory layout correction, dense memory cell optimization, assist feature (AF) optimization, source optimization, complex patterning design rules and design-technology co-optimization (DTCO). The combined optimization capability of these two technologies will therefore have a wide range of useful applications. We investigate the benefits of the new functionality for a few of these advanced applications including correction for photoresist top loss and resist scumming hotspots.

  17. Role of Polyamine Oxidase (PAOh1/SMO) in Human Breast Cancer

    DTIC Science & Technology

    2007-04-01

    polyamine spermidine , 3-aminopropanal, and the reactive oxygen species, H2O2. Previous work by our research group has shown that SMO can be induced by...spermine/ spermidine N1-acetyltransferase (SSAT). Treatment of MCF-10a cells with CSE resulted in a rapid 3-fold induction of SSAT mRNA at the one hour time...and spermine/ spermidine N1 acetyl- transferase (SSAT, open bars) in MCF- 10a human breast cancer cells by cigarette smoke extract (CSE) at the

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

    Lemaire, H.; Barat, E.; Carrel, F.

    In this work, we tested Maximum likelihood expectation-maximization (MLEM) algorithms optimized for gamma imaging applications on two recent coded mask gamma cameras. We respectively took advantage of the characteristics of the GAMPIX and Caliste HD-based gamma cameras: noise reduction thanks to mask/anti-mask procedure but limited energy resolution for GAMPIX, high energy resolution for Caliste HD. One of our short-term perspectives is the test of MAPEM algorithms integrating specific prior values for the data to reconstruct adapted to the gamma imaging topic. (authors)

  19. The bright-star masks for the HSC-SSP survey

    NASA Astrophysics Data System (ADS)

    Coupon, Jean; Czakon, Nicole; Bosch, James; Komiyama, Yutaka; Medezinski, Elinor; Miyazaki, Satoshi; Oguri, Masamune

    2018-01-01

    We present the procedure to build and validate the bright-star masks for the Hyper-Suprime-Cam Strategic Subaru Proposal (HSC-SSP) survey. To identify and mask the saturated stars in the full HSC-SSP footprint, we rely on the Gaia and Tycho-2 star catalogues. We first assemble a pure star catalogue down to GGaia < 18 after removing ˜1.5% of sources that appear extended in the Sloan Digital Sky Survey (SDSS). We perform visual inspection on the early data from the S16A internal release of HSC-SSP, finding that our star catalogue is 99.2% pure down to GGaia < 18. Second, we build the mask regions in an automated way using stacked detected source measurements around bright stars binned per GGaia magnitude. Finally, we validate those masks by visual inspection and comparison with the literature of galaxy number counts and angular two-point correlation functions. This version (Arcturus) supersedes the previous version (Sirius) used in the S16A internal and DR1 public releases. We publicly release the full masks and tools to flag objects in the entire footprint of the planned HSC-SSP observations at "ftp://obsftp.unige.ch/pub/coupon/brightStarMasks/HSC-SSP/".

  20. Machine learning for inverse lithography: using stochastic gradient descent for robust photomask synthesis

    NASA Astrophysics Data System (ADS)

    Jia, Ningning; Y Lam, Edmund

    2010-04-01

    Inverse lithography technology (ILT) synthesizes photomasks by solving an inverse imaging problem through optimization of an appropriate functional. Much effort on ILT is dedicated to deriving superior masks at a nominal process condition. However, the lower k1 factor causes the mask to be more sensitive to process variations. Robustness to major process variations, such as focus and dose variations, is desired. In this paper, we consider the focus variation as a stochastic variable, and treat the mask design as a machine learning problem. The stochastic gradient descent approach, which is a useful tool in machine learning, is adopted to train the mask design. Compared with previous work, simulation shows that the proposed algorithm is effective in producing robust masks.

  1. The masking of beluga whale (Delphinapterus leucas) vocalizations by icebreaker noise

    NASA Astrophysics Data System (ADS)

    Erbe, Christine

    1998-11-01

    This thesis examines the masking effect of underwater noise on beluga whale communication. As ocean water is greatly opaque for light but well conducting for sound, marine mammals rely primarily on their hearing for orientation and communication. Man-made underwater noise has the potential of interfering with sounds used by marine mammals. Masking to the point of incomprehensibility can have fatal results-for the individual, but ultimately for the entire species. As part of our understanding of whether marine mammals can cope with human impact on nature, this thesis is the first to study the interference of real ocean noises with complex animal vocalizations. At the Vancouver Aquarium, a beluga whale was trained for acoustic experiments, during which masked hearing thresholds were measured. Focus lay on noise created by icebreaking ships in the Arctic. As experiments with trained animals are time and cost expensive, various techniques were examined for their ability to model the whale's response. These were human hearing tests, visual spectrogram discrimination, matched filtering, spectrogram cross-correlation, critical band cross-correlation, adaptive filtering and various types of artificial neural networks. The most efficient method with respect to similarity to the whale's data and speed, was a backpropagation neural net. Masked hearing thresholds would be of little use if they could not be related to accessible quantities in the wild. An ocean sound propagation model was applied to determine critical distances between a noise source, a calling whale and a listening whale. Colour diagrams, called maskograms, were invented to illustrate zones of masking in the wild. Results are that bubbler system noise with a source level of 194 dB re 1 μPa at 1 m has a maximum radius of masking of 15 km in a 3- dimensional ocean. Propeller noise with a source level of 203 dB re 1 μPa at 1 m has a maximum radius of masking of 22 km. A naturally occurring icecracking event with a source level of 147 dB re 1 μPa at 1 m only masks if the listening whale is within 8 m of the event. Therefore, in the wild, propeller cavitation noise masks furthest, followed by bubbler system noise, then icecracking noise.

  2. Molecular evolution of the polyamine oxidase gene family in Metazoa

    PubMed Central

    2012-01-01

    Background Polyamine oxidase enzymes catalyze the oxidation of polyamines and acetylpolyamines. Since polyamines are basic regulators of cell growth and proliferation, their homeostasis is crucial for cell life. Members of the polyamine oxidase gene family have been identified in a wide variety of animals, including vertebrates, arthropodes, nematodes, placozoa, as well as in plants and fungi. Polyamine oxidases (PAOs) from yeast can oxidize spermine, N1-acetylspermine, and N1-acetylspermidine, however, in vertebrates two different enzymes, namely spermine oxidase (SMO) and acetylpolyamine oxidase (APAO), specifically catalyze the oxidation of spermine, and N1-acetylspermine/N1-acetylspermidine, respectively. Little is known about the molecular evolutionary history of these enzymes. However, since the yeast PAO is able to catalyze the oxidation of both acetylated and non acetylated polyamines, and in vertebrates these functions are addressed by two specialized polyamine oxidase subfamilies (APAO and SMO), it can be hypothesized an ancestral reference for the former enzyme from which the latter would have been derived. Results We analysed 36 SMO, 26 APAO, and 14 PAO homologue protein sequences from 54 taxa including various vertebrates and invertebrates. The analysis of the full-length sequences and the principal domains of vertebrate and invertebrate PAOs yielded consensus primary protein sequences for vertebrate SMOs and APAOs, and invertebrate PAOs. This analysis, coupled to molecular modeling techniques, also unveiled sequence regions that confer specific structural and functional properties, including substrate specificity, by the different PAO subfamilies. Molecular phylogenetic trees revealed a basal position of all the invertebrates PAO enzymes relative to vertebrate SMOs and APAOs. PAOs from insects constitute a monophyletic clade. Two PAO variants sampled in the amphioxus are basal to the dichotomy between two well supported monophyletic clades including, respectively, all the SMOs and APAOs from vertebrates. The two vertebrate monophyletic clades clustered strictly mirroring the organismal phylogeny of fishes, amphibians, reptiles, birds, and mammals. Evidences from comparative genomic analysis, structural evolution and functional divergence in a phylogenetic framework across Metazoa suggested an evolutionary scenario where the ancestor PAO coding sequence, present in invertebrates as an orthologous gene, has been duplicated in the vertebrate branch to originate the paralogous SMO and APAO genes. A further genome evolution event concerns the SMO gene of placental, but not marsupial and monotremate, mammals which increased its functional variation following an alternative splicing (AS) mechanism. Conclusions In this study the explicit integration in a phylogenomic framework of phylogenetic tree construction, structure prediction, and biochemical function data/prediction, allowed inferring the molecular evolutionary history of the PAO gene family and to disambiguate paralogous genes related by duplication event (SMO and APAO) and orthologous genes related by speciation events (PAOs, SMOs/APAOs). Further, while in vertebrates experimental data corroborate SMO and APAO molecular function predictions, in invertebrates the finding of a supported phylogenetic clusters of insect PAOs and the co-occurrence of two PAO variants in the amphioxus urgently claim the need for future structure-function studies. PMID:22716069

  3. Molecular evolution of the polyamine oxidase gene family in Metazoa.

    PubMed

    Polticelli, Fabio; Salvi, Daniele; Mariottini, Paolo; Amendola, Roberto; Cervelli, Manuela

    2012-06-20

    Polyamine oxidase enzymes catalyze the oxidation of polyamines and acetylpolyamines. Since polyamines are basic regulators of cell growth and proliferation, their homeostasis is crucial for cell life. Members of the polyamine oxidase gene family have been identified in a wide variety of animals, including vertebrates, arthropodes, nematodes, placozoa, as well as in plants and fungi. Polyamine oxidases (PAOs) from yeast can oxidize spermine, N1-acetylspermine, and N1-acetylspermidine, however, in vertebrates two different enzymes, namely spermine oxidase (SMO) and acetylpolyamine oxidase (APAO), specifically catalyze the oxidation of spermine, and N1-acetylspermine/N1-acetylspermidine, respectively. Little is known about the molecular evolutionary history of these enzymes. However, since the yeast PAO is able to catalyze the oxidation of both acetylated and non acetylated polyamines, and in vertebrates these functions are addressed by two specialized polyamine oxidase subfamilies (APAO and SMO), it can be hypothesized an ancestral reference for the former enzyme from which the latter would have been derived. We analysed 36 SMO, 26 APAO, and 14 PAO homologue protein sequences from 54 taxa including various vertebrates and invertebrates. The analysis of the full-length sequences and the principal domains of vertebrate and invertebrate PAOs yielded consensus primary protein sequences for vertebrate SMOs and APAOs, and invertebrate PAOs. This analysis, coupled to molecular modeling techniques, also unveiled sequence regions that confer specific structural and functional properties, including substrate specificity, by the different PAO subfamilies. Molecular phylogenetic trees revealed a basal position of all the invertebrates PAO enzymes relative to vertebrate SMOs and APAOs. PAOs from insects constitute a monophyletic clade. Two PAO variants sampled in the amphioxus are basal to the dichotomy between two well supported monophyletic clades including, respectively, all the SMOs and APAOs from vertebrates. The two vertebrate monophyletic clades clustered strictly mirroring the organismal phylogeny of fishes, amphibians, reptiles, birds, and mammals. Evidences from comparative genomic analysis, structural evolution and functional divergence in a phylogenetic framework across Metazoa suggested an evolutionary scenario where the ancestor PAO coding sequence, present in invertebrates as an orthologous gene, has been duplicated in the vertebrate branch to originate the paralogous SMO and APAO genes. A further genome evolution event concerns the SMO gene of placental, but not marsupial and monotremate, mammals which increased its functional variation following an alternative splicing (AS) mechanism. In this study the explicit integration in a phylogenomic framework of phylogenetic tree construction, structure prediction, and biochemical function data/prediction, allowed inferring the molecular evolutionary history of the PAO gene family and to disambiguate paralogous genes related by duplication event (SMO and APAO) and orthologous genes related by speciation events (PAOs, SMOs/APAOs). Further, while in vertebrates experimental data corroborate SMO and APAO molecular function predictions, in invertebrates the finding of a supported phylogenetic clusters of insect PAOs and the co-occurrence of two PAO variants in the amphioxus urgently claim the need for future structure-function studies.

  4. Wafer hot spot identification through advanced photomask characterization techniques

    NASA Astrophysics Data System (ADS)

    Choi, Yohan; Green, Michael; McMurran, Jeff; Ham, Young; Lin, Howard; Lan, Andy; Yang, Richer; Lung, Mike

    2016-10-01

    As device manufacturers progress through advanced technology nodes, limitations in standard 1-dimensional (1D) mask Critical Dimension (CD) metrics are becoming apparent. Historically, 1D metrics such as Mean to Target (MTT) and CD Uniformity (CDU) have been adequate for end users to evaluate and predict the mask impact on the wafer process. However, the wafer lithographer's process margin is shrinking at advanced nodes to a point that the classical mask CD metrics are no longer adequate to gauge the mask contribution to wafer process error. For example, wafer CDU error at advanced nodes is impacted by mask factors such as 3-dimensional (3D) effects and mask pattern fidelity on subresolution assist features (SRAFs) used in Optical Proximity Correction (OPC) models of ever-increasing complexity. These items are not quantifiable with the 1D metrology techniques of today. Likewise, the mask maker needs advanced characterization methods in order to optimize the mask process to meet the wafer lithographer's needs. These advanced characterization metrics are what is needed to harmonize mask and wafer processes for enhanced wafer hot spot analysis. In this paper, we study advanced mask pattern characterization techniques and their correlation with modeled wafer performance.

  5. 75 FR 81422 - Airworthiness Directives; The Boeing Company Model 767 Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-28

    ... valve, oxygen mask deployment, and burned wires, which could be an ignition source in a hidden area of... extremely remote, and disagrees with the references to the spar shut-off valve, oxygen masks, and... engine. In regard to the airplane's oxygen system, while failure of the oxygen mask deployment system...

  6. The Mask Designs for Space Interferometer Mission (SIM)

    NASA Technical Reports Server (NTRS)

    Wang, Xu

    2008-01-01

    The Space Interferometer Mission (SIM) consists of three interferometers (science, guide1, and guide2) and two optical paths (metrology and starlight). The system requirements for each interferometer/optical path combination are different and sometimes work against each other. A diffraction model is developed to design and optimize various masks to simultaneously meet the system requirements of three interferometers. In this paper, the details of this diffraction model will be described first. Later, the mask design for each interferometer will be presented to demonstrate the system performance compliance. In the end, a tolerance sensitivity study on the geometrical dimension, shape, and the alignment of these masks will be discussed.

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

    Winnek, D.F.

    A method and apparatus for making X-ray photographs which can be viewed in three dimensions with the use of a lenticular screen. The apparatus includes a linear tomograph having a moving X-ray source on one side of a support on which an object is to be placed so that X-rays can pass through the object to the opposite side of the support. A movable cassette on the opposite side of the support moves in a direction opposite to the direction of travel of the X-ray source as the source moves relative to the support. The cassette has an intensifying screen,more » a grating mask provided with uniformly spaced slots for passing X-rays, a lenticular member adjacent to the mask, and a photographic emulsion adjacent to the opposite side of the lenticular member. The cassette has a power device for moving the lenticular member and the emulsion relative to the mask a distance equal to the spacing between a pair of adjacent slots in the mask. The X-rays from the source, after passing through an object on the support, pass into the cassette through the slots of the mask and are focused on the photographic emulsion to result in a continuum of X-ray views of the object. When the emulsion is developed and viewed through the lenticular member, the object can be seen in three dimensions.« less

  8. Second medical opinions: the views of oncology patients and their physicians.

    PubMed

    Philip, Jennifer; Gold, Michelle; Schwarz, Max; Komesaroff, Paul

    2010-09-01

    Second medical opinions (SMOs) are common in oncology practice, but the nature of these consultations has received relatively little attention. This study examines the views of patients with advanced cancer and their physicians of SMOs. Parallel, concurrent surveys were developed for patients and physicians. The first was distributed to outpatients with advanced cancer-attending specialist clinics in an Australian quaternary hospital. The second survey, developed on the basis of results of exploratory interviews with medical oncologists, was distributed to medical oncologists in Australia. Seventeen of fifty two (33%) patients had sought a SMO, most commonly prompted by concerns around communication with their first doctor, the extreme and desperate nature of their medical condition and the need for reassurance. Most (94%) patients found the SMO helpful, with satisfaction related to improved communication and reassurance. Patients were concerned that seeking a second medical opinion may affect their relationship with their primary doctor. Most physicians (82%) reported seeing between one and five SMO per month, with patients being motivated by the need for additional information and reassurance. Physicians regarded SMO patients as having greater information needs (84%), greater psychosocial needs (58%) and requiring more of the physician's time and energy (77%) than other patients. SMOs are common in cancer care with most patients motivated by the need for improved communication, additional information and reassurance. Physicians identify patients who seek SMOs as having additional psychosocial needs compared with other oncology patients.

  9. Speech segregation based-on binaural cue: interaural time difference (itd) and interaural level difference (ild)

    NASA Astrophysics Data System (ADS)

    Nur Farid, Mifta; Arifianto, Dhany

    2016-11-01

    A person who is suffering from hearing loss can be helped by using hearing aids and the most optimal performance of hearing aids are binaural hearing aids because it has similarities to human auditory system. In a conversation at a cocktail party, a person can focus on a single conversation even though the background sound and other people conversation is quite loud. This phenomenon is known as the cocktail party effect. In an early study, has been explained that binaural hearing have an important contribution to the cocktail party effect. So in this study, will be performed separation on the input binaural sound with 2 microphone sensors of two sound sources based on both the binaural cue, interaural time difference (ITD) and interaural level difference (ILD) using binary mask. To estimate value of ITD, is used cross-correlation method which the value of ITD represented as time delay of peak shifting at time-frequency unit. Binary mask is estimated based on pattern of ITD and ILD to relative strength of target that computed statistically using probability density estimation. Results of sound source separation performing well with the value of speech intelligibility using the percent correct word by 86% and 3 dB by SNR.

  10. Expanding the printable design space for lithography processes utilizing a cut mask

    NASA Astrophysics Data System (ADS)

    Wandell, Jerome; Salama, Mohamed; Wilkinson, William; Curtice, Mark; Feng, Jui-Hsuan; Gao, Shao Wen; Asthana, Abhishek

    2016-03-01

    The utilization of a cut-mask in semiconductor patterning processes has been in practice for logic devices since the inception of 32nm-node devices, notably with unidirectional gate level printing. However, the microprocessor applications where cut-mask patterning methods are used are expanding as Self-Aligned Double Patterning (SADP) processes become mainstream for 22/14nm fin diffusion, and sub-14nm metal levels. One common weakness for these types of lithography processes is that the initial pattern requiring the follow-up cut-mask typically uses an extreme off-axis imaging source such as dipole to enhance the resolution and line-width roughness (LWR) for critical dense patterns. This source condition suffers from poor process margin in the semi-dense (forbidden pitch) realm and wrong-way directional design spaces. Common pattern failures in these limited design regions include bridging and extra-printing defects that are difficult to resolve with traditional mask improvement means. This forces the device maker to limit the allowable geometries that a designer may use on a device layer. This paper will demonstrate methods to expand the usable design space on dipole-like processes such as unidirectional gate and SADP processes by utilizing the follow-up cut mask to improve the process window. Traditional mask enhancement means for improving the process window in this design realm will be compared to this new cut-mask approach. The unique advantages and disadvantages of the cut-mask solution will be discussed in contrast to those customary methods.

  11. Matching OPC and masks on 300-mm lithography tools utilizing variable illumination settings

    NASA Astrophysics Data System (ADS)

    Palitzsch, Katrin; Kubis, Michael; Schroeder, Uwe P.; Schumacher, Karl; Frangen, Andreas

    2004-05-01

    CD control is crucial to maximize product yields on 300mm wafers. This is particularly true for DRAM frontend lithography layers, like gate level, and deep trench (capacitor) level. In the DRAM process, large areas of the chip are taken up by array structures, which are difficult to structure due to aggressive pitch requirements. Consequently, the lithography process is centered such that the array structures are printed on target. Optical proximity correction is applied to print gate level structures in the periphery circuitry on target. Only slight differences of the different Zernike terms can cause rather large variations of the proximity curves, resulting in a difference of isolated and semi-isolated lines printed on different tools. If the deviations are too large, tool specific OPC is needed. The same is true for deep trench level, where the length to width ratio of elongated contact-like structures is an important parameter to adjust the electrical properties of the chip. Again, masks with specific biases for tools with different Zernikes are needed to optimize product yield. Additionally, mask making contributes to the CD variation of the process. Theoretically, the CD deviation caused by an off-centered mask process can easily eat up the majority of the CD budget of a lithography process. In practice, masks are very often distributed intelligently among production tools, such that lens and mask effects cancel each other. However, only dose adjusting and mask allocation may still result in a high CD variation with large systematical contributions. By adjusting the illumination settings, we have successfully implemented a method to reduce CD variation on our advanced processes. Especially inner and outer sigma for annular illumination, and the numerical aperture, can be optimized to match mask and stepper properties. This process will be shown to overcome slight lens and mask differences effectively. The effects on lithography process windows have to be considered, nonetheless.

  12. Marquardt's Phi mask: pitfalls of relying on fashion models and the golden ratio to describe a beautiful face.

    PubMed

    Holland, E

    2008-03-01

    Stephen Marquardt has derived a mask from the golden ratio that he claims represents the "ideal" facial archetype. Many have found his mask convincing, including cosmetic surgeons. However, Marquardt's mask is associated with numerous problems. The method used to examine goodness of fit with the proportions in the mask is faulty. The mask is ill-suited for non-European populations, especially sub-Saharan Africans and East Asians. The mask also appears to approximate the face shape of masculinized European women. Given that the general public strongly and overwhelmingly prefers above average facial femininity in women, white women seeking aesthetic facial surgery would be ill-advised to aim toward a better fit with Marquardt's mask. This article aims to show the proper way of assessing goodness of fit with Marquardt's mask, to address the shape of the mask as it pertains to masculinity-femininity, and to discuss the broader issue of an objective assessment of facial attractiveness. Generalized Procrustes analysis is used to show how goodness of fit with Marquardt's mask can be assessed. Thin-plate spline analysis is used to illustrate visually how sample faces, including northwestern European averages, differ from Marquardt's mask. Marquardt's mask best describes the facial proportions of masculinized white women as seen in fashion models. Marquardt's mask does not appear to describe "ideal" face shape even for white women because its proportions are inconsistent with the optimal preferences of most people, especially with regard to femininity.

  13. Optimization of wavefront coding imaging system using heuristic algorithms

    NASA Astrophysics Data System (ADS)

    González-Amador, E.; Padilla-Vivanco, A.; Toxqui-Quitl, C.; Zermeño-Loreto, O.

    2017-08-01

    Wavefront Coding (WFC) systems make use of an aspheric Phase-Mask (PM) and digital image processing to extend the Depth of Field (EDoF) of computational imaging systems. For years, several kinds of PM have been designed to produce a point spread function (PSF) near defocus-invariant. In this paper, the optimization of the phase deviation parameter is done by means of genetic algorithms (GAs). In this, the merit function minimizes the mean square error (MSE) between the diffraction limited Modulated Transfer Function (MTF) and the MTF of the system that is wavefront coded with different misfocus. WFC systems were simulated using the cubic, trefoil, and 4 Zernike polynomials phase-masks. Numerical results show defocus invariance aberration in all cases. Nevertheless, the best results are obtained by using the trefoil phase-mask, because the decoded image is almost free of artifacts.

  14. Optimized phase mask to realize retro-reflection reduction for optical systems

    NASA Astrophysics Data System (ADS)

    He, Sifeng; Gong, Mali

    2017-10-01

    Aiming at the threats to the active laser detection systems of electro-optical devices due to the cat-eye effect, a novel solution is put forward to realize retro-reflection reduction in this paper. According to the demands of both cat-eye effect reduction and the image quality maintenance of electro-optical devices, a symmetric phase mask is achieved from a stationary phase method and a fast Fourier transform algorithm. Then, based on a comparison of peak normalized cross-correlation (PNCC) between the different defocus parameters, the optimal imaging position can be obtained. After modification with the designed phase mask, the cat-eye effect peak intensity can be reduced by two orders of magnitude while maintaining good image quality and high modulation transfer function (MTF). Furthermore, a practical design example is introduced to demonstrate the feasibility of our proposed approach.

  15. Wafer hot spot identification through advanced photomask characterization techniques: part 2

    NASA Astrophysics Data System (ADS)

    Choi, Yohan; Green, Michael; Cho, Young; Ham, Young; Lin, Howard; Lan, Andy; Yang, Richer; Lung, Mike

    2017-03-01

    Historically, 1D metrics such as Mean to Target (MTT) and CD Uniformity (CDU) have been adequate for mask end users to evaluate and predict the mask impact on the wafer process. However, the wafer lithographer's process margin is shrinking at advanced nodes to a point that classical mask CD metrics are no longer adequate to gauge the mask contribution to wafer process error. For example, wafer CDU error at advanced nodes is impacted by mask factors such as 3-dimensional (3D) effects and mask pattern fidelity on sub-resolution assist features (SRAFs) used in Optical Proximity Correction (OPC) models of ever-increasing complexity. To overcome the limitation of 1D metrics, there are numerous on-going industry efforts to better define wafer-predictive metrics through both standard mask metrology and aerial CD methods. Even with these improvements, the industry continues to struggle to define useful correlative metrics that link the mask to final device performance. In part 1 of this work, we utilized advanced mask pattern characterization techniques to extract potential hot spots on the mask and link them, theoretically, to issues with final wafer performance. In this paper, part 2, we complete the work by verifying these techniques at wafer level. The test vehicle (TV) that was used for hot spot detection on the mask in part 1 will be used to expose wafers. The results will be used to verify the mask-level predictions. Finally, wafer performance with predicted and verified mask/wafer condition will be shown as the result of advanced mask characterization. The goal is to maximize mask end user yield through mask-wafer technology harmonization. This harmonization will provide the necessary feedback to determine optimum design, mask specifications, and mask-making conditions for optimal wafer process margin.

  16. Wavelet-Smoothed Interpolation of Masked Scientific Data for JPEG 2000 Compression

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

    Brislawn, Christopher M.

    2012-08-13

    How should we manage scientific data with 'holes'? Some applications, like JPEG 2000, expect logically rectangular data, but some sources, like the Parallel Ocean Program (POP), generate data that isn't defined on certain subsets. We refer to grid points that lack well-defined, scientifically meaningful sample values as 'masked' samples. Wavelet-smoothing is a highly scalable interpolation scheme for regions with complex boundaries on logically rectangular grids. Computation is based on forward/inverse discrete wavelet transforms, so runtime complexity and memory scale linearly with respect to sample count. Efficient state-of-the-art minimal realizations yield small constants (O(10)) for arithmetic complexity scaling, and in-situ implementationmore » techniques make optimal use of memory. Implementation in two dimensions using tensor product filter banks is straighsorward and should generalize routinely to higher dimensions. No hand-tuning required when the interpolation mask changes, making the method aeractive for problems with time-varying masks. Well-suited for interpolating undefined samples prior to JPEG 2000 encoding. The method outperforms global mean interpolation, as judged by both SNR rate-distortion performance and low-rate artifact mitigation, for data distributions whose histograms do not take the form of sharply peaked, symmetric, unimodal probability density functions. These performance advantages can hold even for data whose distribution differs only moderately from the peaked unimodal case, as demonstrated by POP salinity data. The interpolation method is very general and is not tied to any particular class of applications, could be used for more generic smooth interpolation.« less

  17. Deformably registering and annotating whole CLARITY brains to an atlas via masked LDDMM

    NASA Astrophysics Data System (ADS)

    Kutten, Kwame S.; Vogelstein, Joshua T.; Charon, Nicolas; Ye, Li; Deisseroth, Karl; Miller, Michael I.

    2016-04-01

    The CLARITY method renders brains optically transparent to enable high-resolution imaging in the structurally intact brain. Anatomically annotating CLARITY brains is necessary for discovering which regions contain signals of interest. Manually annotating whole-brain, terabyte CLARITY images is difficult, time-consuming, subjective, and error-prone. Automatically registering CLARITY images to a pre-annotated brain atlas offers a solution, but is difficult for several reasons. Removal of the brain from the skull and subsequent storage and processing cause variable non-rigid deformations, thus compounding inter-subject anatomical variability. Additionally, the signal in CLARITY images arises from various biochemical contrast agents which only sparsely label brain structures. This sparse labeling challenges the most commonly used registration algorithms that need to match image histogram statistics to the more densely labeled histological brain atlases. The standard method is a multiscale Mutual Information B-spline algorithm that dynamically generates an average template as an intermediate registration target. We determined that this method performs poorly when registering CLARITY brains to the Allen Institute's Mouse Reference Atlas (ARA), because the image histogram statistics are poorly matched. Therefore, we developed a method (Mask-LDDMM) for registering CLARITY images, that automatically finds the brain boundary and learns the optimal deformation between the brain and atlas masks. Using Mask-LDDMM without an average template provided better results than the standard approach when registering CLARITY brains to the ARA. The LDDMM pipelines developed here provide a fast automated way to anatomically annotate CLARITY images; our code is available as open source software at http://NeuroData.io.

  18. The Effects of Screw Configuration and Polymeric Carriers on Hot-Melt Extruded Taste-Masked Formulations Incorporated into Orally Disintegrating Tablets

    PubMed Central

    Morott, Joseph T.; Pimparade, Manjeet; Park, Jun-Bom; Worley, Chelsea P.; Majumdar, Soumyajit; Lian, Zhuoyang; Pinto, Elanor; Bi, Yunxia; Durig, Thomas; Repka, Michael A.

    2015-01-01

    The primary aim of this research was to produce successfully taste masked formulations of Sildenafil Citrate (SC) using hot-melt extrusion (HME) technology. Multiple screw configurations and polymeric carriers were evaluated for their effects on taste masking efficiency, which was assessed by both E-tongue analysis and in vitro dissolution in simulated salivary fluid (SSF, pH 6.8 artificial saliva). The screw configurations were further assessed for their effects on the morphology of the API using PXRD, FT-IR and mid-infrared chemical imaging. It was determined that the screw configuration had a profound effect on the taste masking efficiency of the formulations as a result of altering the physical state of the API. Selected extruded formulations using ethylcellulose (EC) with a pore former were further formulated into orally disintegrating tablets (ODTs), which were optimized by varying the grade and percentage of the superdisintegrant used. An optimized disintegration time of approximately 8 seconds was achieved. The final ODT formulation exhibited excellent taste masking properties with over 85% drug release in gastric media as well as physical tablet properties. Interestingly, friability, which tends to be a common concern when formulating ODTs, was well within the acceptable limits (<1%) for common tablets. PMID:25410968

  19. The Role of RT Carry-Over for Congruence Sequence Effects in Masked Priming

    ERIC Educational Resources Information Center

    Huber-Huber, Christoph; Ansorge, Ulrich

    2017-01-01

    The present study disentangles 2 sources of the congruence sequence effect with masked primes: congruence and response time of the previous trial (reaction time [RT] carry-over). Using arrows as primes and targets and a metacontrast masking procedure we found congruence as well as congruence sequence effects. In addition, congruence sequence…

  20. Design and Optimization of a Light-Emitting Diode Projection Micro-Stereolithography Three-Dimensional Manufacturing System

    DTIC Science & Technology

    2012-12-11

    ment, and difficulties creating high aspect ratio features. In addition, conventional mask-based lithography cannot create curved surfaces in the...There are three types of digital mask technologies: (1) liquid crystal display (LCD); (2) digital micromirror device (DMD); and (3) LCoS. LCD is the

  1. Method and apparatus for inspecting an EUV mask blank

    DOEpatents

    Goldberg, Kenneth A.

    2005-11-08

    An apparatus and method for at-wavelength EUV mask-blank characterization for inspection of moderate and low spatial frequency coating uniformity using a synchrotron or other source of EUV light. The apparatus provides for rapid, non-destruction, non-contact, at-wavelength qualification of large mask areas, and can be self-calibrating or be calibrated to well-characterized reference samples. It can further check for spatial variation of mask reflectivity or for global differences among masks. The apparatus and method is particularly suited for inspection of coating uniformity and quality and can detect defects in the order of 50 .mu.m and above.

  2. Assessment of molecular contamination in mask pod

    NASA Astrophysics Data System (ADS)

    Foray, Jean Marie; Dejaune, Patrice; Sergent, Pierre; Gough, Stuart; Cheung, D.; Davenet, Magali; Favre, Arnaud; Rude, C.; Trautmann, T.; Tissier, Michel; Fontaine, H.; Veillerot, M.; Avary, K.; Hollein, I.; Lerit, R.

    2008-04-01

    Context/ study Motivation: Contamination and especially Airbone Molecular Contamination (AMC) is a critical issue for mask material flow with a severe and fairly unpredictable risk of induced contamination and damages especially for 193 nm lithography. It is therefore essential to measure, to understand and then try to reduce AMC in mask environment. Mask material flow was studied in a global approach by a pool of European partners, especially within the frame of European MEDEA+ project, so called "MUSCLE". This paper deals with results and assessment of mask pod environment in term of molecular contamination in a first step, then in a second step preliminary studies to reduce mask pod influence and contamination due to material out gassing. Approach and techniques: A specific assessment of environmental / molecular contamination along the supply chain was performed by all partners. After previous work presented at EMLC 07, further studies were performed on real time contamination measurement pod at different sites locations (including Mask manufacturing site, blank manufacturing sites, IC fab). Studies were linked to the main critical issues: cleaning, storage, handling, materials and processes. Contamination measurement campaigns were carried out along the mask supply chain using specific Adixen analyzer in order to monitor in real time organic contaminants (ppb level) in mask pods. Key results would be presented: VOC, AMC and humidity level on different kinds of mask carriers, impact of basic cleaning on pod outgassing measurement (VOC, NH3), and process influence on pod contamination... In a second step, preliminary specific pod conditioning studies for better pod environment were performed based on Adixen vacuum process. Process influence had been experimentally measured in term of molecular outgassing from mask pods. Different AMC experimental characterization methods had been carried out leading to results on a wide range of organic and inorganic contaminants: by inline techniques based on Adixen humidity, also VOC and organic sensors, together by off-line techniques already used in the extensive previous mask pods benchmark (TD-GCMS & Ionic Chromatography). Humidity and VOC levels from mask carriers had shown significant reduction after Adixen pod conditioning process. Focus had been made on optimized vacuum step (for AMC) after particles carrier cleaning cycle. Based upon these key results new procedures, as well as guidelines for mask carrier cleaning optimization are proposed to improve pod contamination control. Summary results/next steps: This paper reports molecular contamination measurement campaigns performed by a pool of European partners along the mask supply chain. It allows us to investigate, identify and quantify critical molecular contamination in mask pod, as well as VOC and humidity, issues depending on locations, uses, and carrier's type. Preliminary studies highlight initial process solutions for pods conditioning that are being used for short term industrialization and further industrialized.

  3. Masked Proportional Routing

    NASA Technical Reports Server (NTRS)

    Wolpert, David

    2004-01-01

    Masked proportional routing is an improved procedure for choosing links between adjacent nodes of a network for the purpose of transporting an entity from a source node ("A") to a destination node ("B"). The entity could be, for example, a physical object to be shipped, in which case the nodes would represent waypoints and the links would represent roads or other paths between waypoints. For another example, the entity could be a message or packet of data to be transmitted from A to B, in which case the nodes could be computer-controlled switching stations and the links could be communication channels between the stations. In yet another example, an entity could represent a workpiece while links and nodes could represent, respectively, manufacturing processes and stages in the progress of the workpiece towards a finished product. More generally, the nodes could represent states of an entity and the links could represent allowed transitions of the entity. The purpose of masked proportional routing and of related prior routing procedures is to schedule transitions of entities from their initial states ("A") to their final states ("B") in such a manner as to minimize a cost or to attain some other measure of optimality or efficiency. Masked proportional routing follows a distributed (in the sense of decentralized) approach to probabilistically or deterministically choosing the links. It was developed to satisfy a need for a routing procedure that 1. Does not always choose the same link(s), even for two instances characterized by identical estimated values of associated cost functions; 2. Enables a graceful transition from one set of links to another set of links as the circumstances of operation of the network change over time; 3. Is preferably amenable to separate optimization of different portions of the network; 4. Is preferably usable in a network in which some of the routing decisions are made by one or more other procedure(s); 5. Preferably does not cause an entity to visit the same node twice; and 6. Preferably can be modified so that separate entities moving from A to B do not arrive out of order.

  4. Optical inspection of NGL masks

    NASA Astrophysics Data System (ADS)

    Pettibone, Donald W.; Stokowski, Stanley E.

    2004-12-01

    For the last five years KLA-Tencor and our joint venture partners have pursued a research program studying the ability of optical inspection tools to meet the inspection needs of possible NGL lithographies. The NGL technologies that we have studied include SCALPEL, PREVAIL, EUV lithography, and Step and Flash Imprint Lithography. We will discuss the sensitivity of the inspection tools and mask design factors that affect tool sensitivity. Most of the work has been directed towards EUV mask inspection and how to optimize the mask to facilitate inspection. Our partners have succeeded in making high contrast EUV masks ranging in contrast from 70% to 98%. Die to die and die to database inspection of EUV masks have been achieved with a sensitivity that is comparable to what can be achieved with conventional photomasks, approximately 80nm defect sensitivity. We have inspected SCALPEL masks successfully. We have found a limitation of optical inspection when applied to PREVAIL stencil masks. We have run inspections on SFIL masks in die to die, reflected light, in an effort to provide feedback to improve the masks. We have used a UV inspection system to inspect both unpatterned EUV substrates (no coatings) and blanks (with EUV multilayer coatings). These inspection results have proven useful in driving down the substrate and blank defect levels.

  5. Investigating gas sensing mechanism of graphene oxide (GO) thin films through cross-selectivity to various gases

    NASA Astrophysics Data System (ADS)

    Kumar, Shani; Dhingra, Vishal; Garg, Amit; Chowdhuri, Arijit

    2016-05-01

    Worldwide researchers are actively engaged in utilizing Graphene and its related materials in gas sensing applications. A high surface-to-volume ratio that offers scope of optimization leading to enhanced sensing performance besides lower sensor operating temperatures are some advantages that graphene based sensors possess over conventional semiconducting metal oxide (SMO) sensors. Conventional SMO based gas sensors are known to suffer from problems of cross-selectivity where selectivity is understood to be a gas sensor's ability to preferentially detect one particular gas without responding to or experiencing interference from other gases present in the ambient. In the current study gas sensing mechanism of Graphene oxide (GO) thin films is investigated by repeatedly exposing the sensing configuration to various gases and its cross-selectivity response to the same is examined. In the investigation typical gas sensing response characteristics of the sensor configuration are studied in both oxidizing as well as reducing environments. The gas sensing data is acquired by means of Keithley 6487 picoammeter which is interfaced with a customized Gas Sensing Test Rig (GSTR) that provides a controlled ambient to the sensors for measurement of reproducible characteristics. GSTR further provided the option of varying the operating temperature and gas concentration for the different sensor configurations under study. XRD studies indicate formation of GO with typical crystallite size of 4.2 nm. UV-Vis investigations reveal a typical band-gap of 4.42 (eV) which is in conformity with those reported in the available literature.1,2

  6. Coherent optical processing using noncoherent light after source masking.

    PubMed

    Boopathi, V; Vasu, R M

    1992-01-10

    Coherent optical processing starting with spatially noncoherent illumination is described. Good spatial coherence is introduced in the far field by modulating a noncoherent source when masks with sharp autocorrelation are used. The far-field mutual coherence function of light is measured and it is seen that, for the masks and the source size used here, we get a fairly large area over which the mutual coherence function is high and flat. We demonstrate traditional coherent processing operations such as Fourier transformation and image deblurring when coherent light that is produced in the above fashion is used. A coherence-redundancy merit function is defined for this type of processing system. It is experimentally demonstrated that the processing system introduced here has superior blemish tolerance compared with a traditional processor that uses coherent illumination.

  7. Advances in low-defect multilayers for EUVL mask blanks

    NASA Astrophysics Data System (ADS)

    Folta, James A.; Davidson, J. Courtney; Larson, Cindy C.; Walton, Christopher C.; Kearney, Patrick A.

    2002-07-01

    Low-defect multilayer coatings are required to fabricate mask blanks for Extreme Ultraviolet Lithography (EUVL). The mask blanks consist of high reflectance EUV multilayers on low thermal expansion substrates. A defect density of 0.0025 printable defects/cm2 for both the mask substrate and the multilayer is required to provide a mask blank yield of 60 percent. Current low defect multilayer coating technology allows repeated coating-added defect levels of 0.05/cm2 for defects greater than 90 nm polystyrene latex sphere (PSL) equivalent size for lots of 20 substrates. Extended clean operation of the coating system at levels below 0.08/cm2 for 3 months of operation has also been achieved. Two substrates with zero added defects in the quality area have been fabricated, providing an existence proof that ultra low defect coatings are possible. Increasing the ion source-to-target distance from 410 to 560 mm to reduce undesired coating of the ion source caused the defect density to increase to 0.2/cm2. Deposition and etching diagnostic witness substrates and deposition pinhole cameras showed a much higher level of ion beam spillover (ions missing the sputter target) than expected. Future work will quantify beam spillover, and test designs to reduce spillover, if it is confirmed to be the cause of the increased defect level. The LDD system will also be upgraded to allow clean coating of standard format mask substrates. The upgrade will confirm that the low defect process developed on Si wafers is compatible with the standard mask format 152 mm square substrates, and will provide a clean supply of EUVL mask blanks needed to support development of EUVL mask patterning processes and clean mask handling technologies.

  8. Applications of MICP source for next-generation photomask process

    NASA Astrophysics Data System (ADS)

    Kwon, Hyuk-Joo; Chang, Byung-Soo; Choi, Boo-Yeon; Park, Kyung H.; Jeong, Soo-Hong

    2000-07-01

    As critical dimensions of photomask extends into submicron range, critical dimension uniformity, edge roughness, macro loading effect, and pattern slope become tighter than before. Fabrication of photomask relies on the ability to pattern features with anisotropic profile. To improve critical dimension uniformity, dry etcher is one of the solution and inductively coupled plasma (ICP) sources have become one of promising high density plasma sources for dry etcher. In this paper, we have utilized dry etcher system with multi-pole ICP source for Cr etch and MoSi etch and have investigated critical dimension uniformity, slope, and defects. We will present dry etch process data by process optimization of newly designed dry etcher system. The designed pattern area is 132 by 132 mm2 with 23 by 23 matrix test patterns. 3 (sigma) of critical dimension uniformity is below 12 nm at 0.8 - 3.0 micrometers . In most cases, we can obtain zero defect masks which is operated by face- down loading.

  9. Design criteria for small coded aperture masks in gamma-ray astronomy

    NASA Technical Reports Server (NTRS)

    Sembay, S.; Gehrels, Neil

    1990-01-01

    Most theoretical work on coded aperture masks in X-ray and low-energy gamma-ray astronomy has concentrated on masks with large numbers of elements. For gamma-ray spectrometers in the MeV range, the detector plane usually has only a few discrete elements, so that masks with small numbers of elements are called for. For this case it is feasible to analyze by computer all the possible mask patterns of given dimension to find the ones that best satisfy the desired performance criteria. A particular set of performance criteria for comparing the flux sensitivities, source positioning accuracies and transparencies of different mask patterns is developed. The results of such a computer analysis for masks up to dimension 5 x 5 unit cell are presented and it is concluded that there is a great deal of flexibility in the choice of mask pattern for each dimension.

  10. Use of an Innovative Personality-Mindset Profiling Tool to Guide Culture-Change Strategies among Different Healthcare Worker Groups.

    PubMed

    Grayson, M Lindsay; Macesic, Nenad; Huang, G Khai; Bond, Katherine; Fletcher, Jason; Gilbert, Gwendolyn L; Gordon, David L; Hellsten, Jane F; Iredell, Jonathan; Keighley, Caitlin; Stuart, Rhonda L; Xuereb, Charles S; Cruickshank, Marilyn

    2015-01-01

    Important culture-change initiatives (e.g. improving hand hygiene compliance) are frequently associated with variable uptake among different healthcare worker (HCW) categories. Inherent personality differences between these groups may explain change uptake and help improve future intervention design. We used an innovative personality-profiling tool (ColourGrid®) to assess personality differences among standard HCW categories at five large Australian hospitals using two data sources (HCW participant surveys [PS] and generic institution-wide human resource [HR] data) to: a) compare the relative accuracy of these two sources; b) identify differences between HCW groups and c) use the observed profiles to guide design strategies to improve uptake of three clinically-important initiatives (improved hand hygiene, antimicrobial stewardship and isolation procedure adherence). Results from 34,243 HCWs (HR data) and 1045 survey participants (PS data) suggest that HCWs were different from the general population, displaying more individualism, lower power distance, less uncertainty avoidance and greater cynicism about advertising messages. HR and PS data were highly concordant in identifying differences between the three key HCW categories (doctors, nursing/allied-health, support services) and predicting appropriate implementation strategies. Among doctors, the data suggest that key messaging should differ between full-time vs part-time (visiting) senior medical officers (SMO, VMO) and junior hospital medical officers (HMO), with SMO messaging focused on evidence-based compliance, VMO initiatives emphasising structured mandatory controls and prestige loss for non-adherence, and for HMOs focusing on leadership opportunity and future career risk for non-adherence. Compared to current standardised approaches, targeted interventions based on personality differences between HCW categories should result in improved infection control-related culture-change uptake. Personality profiling based on HR data may represent a useful means of developing a national culture-change "blueprint" for HCW education.

  11. Bubble masks for time-encoded imaging of fast neutrons.

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

    Brubaker, Erik; Brennan, James S.; Marleau, Peter

    2013-09-01

    Time-encoded imaging is an approach to directional radiation detection that is being developed at SNL with a focus on fast neutron directional detection. In this technique, a time modulation of a detected neutron signal is inducedtypically, a moving mask that attenuates neutrons with a time structure that depends on the source position. An important challenge in time-encoded imaging is to develop high-resolution two-dimensional imaging capabilities; building a mechanically moving high-resolution mask presents challenges both theoretical and technical. We have investigated an alternative to mechanical masks that replaces the solid mask with a liquid such as mineral oil. Instead of fixedmore » blocks of solid material that move in pre-defined patterns, the oil is contained in tubing structures, and carefully introduced air gapsbubblespropagate through the tubing, generating moving patterns of oil mask elements and air apertures. Compared to current moving-mask techniques, the bubble mask is simple, since mechanical motion is replaced by gravity-driven bubble propagation; it is flexible, since arbitrary bubble patterns can be generated by a software-controlled valve actuator; and it is potentially high performance, since the tubing and bubble size can be tuned for high-resolution imaging requirements. We have built and tested various single-tube mask elements, and will present results on bubble introduction and propagation as a function of tubing size and cross-sectional shape; real-time bubble position tracking; neutron source imaging tests; and reconstruction techniques demonstrated on simple test data as well as a simulated full detector system.« less

  12. Optimizing defect inspection strategy through the use of design-aware database control layers

    NASA Astrophysics Data System (ADS)

    Stoler, Dvori; Ruch, Wayne; Ma, Weimin; Chakravarty, Swapnajit; Liu, Steven; Morgan, Ray; Valadez, John; Moore, Bill; Burns, John

    2007-10-01

    Resolution limitations in the mask making process can cause differences between the features that appear in a database and those printed to a reticle. These differences may result from intentional or unintentional features in the database exceeding the resolution limit of the mask making process such as small gaps or lines in the data, line end shortening on small sub-resolution assist features etc creating challenges to both mask writing and mask inspection. Areas with high variance from design to mask, often referred to as high MEEF areas (mask error enhancement factor), become highly problematic and can directly impact mask and device yield, mask manufacturing cycle time and ultimately mask costs. Specific to mask inspection it may be desirable to inspect certain non-critical or non-relevant features at reduced sensitivity so as not to detect real, but less significant process defects. In contrast there may also be times where increased sensitivity is required for critical mask features or areas. Until recently, this process was extremely manual, creating added time and cost to the mask inspection cycle. Shifting to more intelligent and automated inspection flows is the key focus of this paper. A novel approach to importing design data directly into the mask inspection to include both MDP generated MRC errors files and LRC generated MEEF files. The results of recently developed inspection and review capability based upon controlling defect inspection using design aware data base control layers on a pixel basis are discussed. Typical mask shop applications and implementations will be shown.

  13. Trends in pharmaceutical taste masking technologies: a patent review.

    PubMed

    Ayenew, Zelalem; Puri, Vibha; Kumar, Lokesh; Bansal, Arvind K

    2009-01-01

    According to the year 2003 survey of pediatricians by the American Association of Pediatrics, unpleasant taste was the biggest barrier for completing treatment in pediatrics. The field of taste masking of active pharmaceutical ingredients (API) has been continuously evolving with varied technologies and new excipients. The article reviews the trends in taste masking technologies by studying the current state of the art patent database for the span of year 1997 to 2007. The worldwide database of European patent office (http://ep.espacenet.com) was employed to collect the patents and patent applications. It also discusses the possible reasons for the change of preferences in the taste masking technologies with time. The prime factors critical to the selection of an optimal taste masking technique such as the extent of drug bitterness, solubility, particle characteristics, dosage form and dose are briefly discussed.

  14. Cryogenic Etching of High Aspect Ratio 400 nm Pitch Silicon Gratings.

    PubMed

    Miao, Houxun; Chen, Lei; Mirzaeimoghri, Mona; Kasica, Richard; Wen, Han

    2016-10-01

    The cryogenic process and Bosch process are two widely used processes for reactive ion etching of high aspect ratio silicon structures. This paper focuses on the cryogenic deep etching of 400 nm pitch silicon gratings with various etching mask materials including polymer, Cr, SiO 2 and Cr-on-polymer. The undercut is found to be the key factor limiting the achievable aspect ratio for the direct hard masks of Cr and SiO 2 , while the etch selectivity responds to the limitation of the polymer mask. The Cr-on-polymer mask provides the same high selectivity as Cr and reduces the excessive undercut introduced by direct hard masks. By optimizing the etching parameters, we etched a 400 nm pitch grating to ≈ 10.6 μ m depth, corresponding to an aspect ratio of ≈ 53.

  15. Thyroid hormone regulates the expression of the sonic hedgehog signaling pathway in the embryonic and adult Mammalian brain.

    PubMed

    Desouza, Lynette A; Sathanoori, Malini; Kapoor, Richa; Rajadhyaksha, Neha; Gonzalez, Luis E; Kottmann, Andreas H; Tole, Shubha; Vaidya, Vidita A

    2011-05-01

    Thyroid hormone is important for development and plasticity in the immature and adult mammalian brain. Several thyroid hormone-responsive genes are regulated during specific developmental time windows, with relatively few influenced across the lifespan. We provide novel evidence that thyroid hormone regulates expression of the key developmental morphogen sonic hedgehog (Shh), and its coreceptors patched (Ptc) and smoothened (Smo), in the early embryonic and adult forebrain. Maternal hypo- and hyperthyroidism bidirectionally influenced Shh mRNA in embryonic forebrain signaling centers at stages before fetal thyroid hormone synthesis. Further, Smo and Ptc expression were significantly decreased in the forebrain of embryos derived from hypothyroid dams. Adult-onset thyroid hormone perturbations also regulated expression of the Shh pathway bidirectionally, with a significant induction of Shh, Ptc, and Smo after hyperthyroidism and a decline in Smo expression in the hypothyroid brain. Short-term T₃ administration resulted in a significant induction of cortical Shh mRNA expression and also enhanced reporter gene expression in Shh(+/LacZ) mice. Further, acute T₃ treatment of cortical neuronal cultures resulted in a rapid and significant increase in Shh mRNA, suggesting direct effects. Chromatin immunoprecipitation assays performed on adult neocortex indicated enhanced histone acetylation at the Shh promoter after acute T₃ administration, providing further support that Shh is a thyroid hormone-responsive gene. Our results indicate that maternal and adult-onset perturbations of euthyroid status cause robust and region-specific changes in the Shh pathway in the embryonic and adult forebrain, implicating Shh as a possible mechanistic link for specific neurodevelopmental effects of thyroid hormone.

  16. Current twin studies in Germany: report on CoSMoS, SOEP, and ChronoS.

    PubMed

    Hahn, Elisabeth; Gottschling, Juliana; Spinath, Frank M

    2013-02-01

    This article summarizes the status of three recent German twin studies: CoSMoS, SOEP, and ChronoS. The German twin study on Cognitive Ability, Self-Reported Motivation, and School Achievement (CoSMoS) is a three-wave longitudinal study of monozygotic and dizygotic twins reared together, and aims to investigate predictors of and influences on school performance. In the first wave of the data collection in 2005, 408 pairs of twins aged between 7 and 11 as well as their parents participated in CoSMoS. The SOEP twin study is an extended twin study, which has combined data from monozygotic and dizygotic twins reared together with additional data from full sibling pairs, mother-child, and grandparent-child dyads who participated in the German Socio-Economic Panel (GSOEP) study. The SOEP twin project comprises about 350 twin and 950 non-twin pairs aged between 17 and 70. Data were collected between 2009 and 2010, with a focus on personality traits, wellbeing, education, employment, income, living situation, life-satisfaction, and several attitudes. The aim of the Chronotype twin study (ChronoS) was to examine genetic and environmental influences on chronotype (morningness and eveningness), coping strategies, and several aspects of the previous SOEP twin project in a sample of 301 twin pairs aged between 19 and 76 years, recruited in 2010 and 2011. Part of the ChronoS twin sample also participated in the earlier SOEP twin study, representing a second wave of assessments. We briefly describe the design and contents of these three studies as well as selected recent findings.

  17. Projected 21st century coastal flooding in the Southern California Bight. Part 1: Development of the third generation CoSMoS model

    USGS Publications Warehouse

    O'Neill, Andrea; Erikson, Li; Barnard, Patrick; Limber, Patrick; Vitousek, Sean; Warrick, Jonathan; Foxgrover, Amy C.; Lovering, Jessica

    2018-01-01

    Due to the effects of climate change over the course of the next century, the combination of rising sea levels, severe storms, and coastal change will threaten the sustainability of coastal communities, development, and ecosystems as we know them today. To clearly identify coastal vulnerabilities and develop appropriate adaptation strategies due to projected increased levels of coastal flooding and erosion, coastal managers need local-scale hazards projections using the best available climate and coastal science. In collaboration with leading scientists world-wide, the USGS designed the Coastal Storm Modeling System (CoSMoS) to assess the coastal impacts of climate change for the California coast, including the combination of sea-level rise, storms, and coastal change. In this project, we directly address the needs of coastal resource managers in Southern California by integrating a vast range of global climate change projections in a thorough and comprehensive numerical modeling framework. In Part 1 of a two-part submission on CoSMoS, methods and the latest improvements are discussed, and an example of hazard projections is presented.

  18. Metabolites in vertebrate Hedgehog signaling.

    PubMed

    Roberg-Larsen, Hanne; Strand, Martin Frank; Krauss, Stefan; Wilson, Steven Ray

    2014-04-11

    The Hedgehog (HH) signaling pathway is critical in embryonic development, stem cell biology, tissue homeostasis, chemoattraction and synapse formation. Irregular HH signaling is associated with a number of disease conditions including congenital disorders and cancer. In particular, deregulation of HH signaling has been linked to skin, brain, lung, colon and pancreatic cancers. Key mediators of the HH signaling pathway are the 12-pass membrane protein Patched (PTC), the 7-pass membrane protein Smoothened (SMO) and the GLI transcription factors. PTC shares homology with the RND family of small-molecule transporters and it has been proposed that it interferes with SMO through metabolites. Although a conclusive picture is lacking, substantial efforts are made to identify and understand natural metabolites/sterols, including cholesterol, vitamin D3, oxysterols and glucocorticoides, that may be affected by, or influence the HH signaling cascade at the level of PTC and SMO. In this review we will elaborate the role of metabolites in HH signaling with a focus on oxysterols, and discuss advancements in modern analytical approaches in the field. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Primary Cilia Negatively Regulate Melanogenesis in Melanocytes and Pigmentation in a Human Skin Model.

    PubMed

    Choi, Hyunjung; Shin, Ji Hyun; Kim, Eun Sung; Park, So Jung; Bae, Il-Hong; Jo, Yoon Kyung; Jeong, In Young; Kim, Hyoung-June; Lee, Youngjin; Park, Hea Chul; Jeon, Hong Bae; Kim, Ki Woo; Lee, Tae Ryong; Cho, Dong-Hyung

    2016-01-01

    The primary cilium is an organelle protruding from the cell body that senses external stimuli including chemical, mechanical, light, osmotic, fluid flow, and gravitational signals. Skin is always exposed to the external environment and responds to external stimuli. Therefore, it is possible that primary cilia have an important role in skin. Ciliogenesis was reported to be involved in developmental processes in skin, such as keratinocyte differentiation and hair formation. However, the relation between skin pigmentation and primary cilia is largely unknown. Here, we observed that increased melanogenesis in melanocytes treated with a melanogenic inducer was inhibited by a ciliogenesis inducer, cytochalasin D, and serum-free culture. However, these inhibitory effects disappeared in GLI2 knockdown cells. In addition, activation of sonic hedgehog (SHH)-smoothened (Smo) signaling pathway by a Smo agonist, SAG inhibited melanin synthesis in melanocytes and pigmentation in a human skin model. On the contrary, an inhibitor of primary cilium formation, ciliobrevin A1, activated melanogenesis in melanocytes. These results suggest that skin pigmentation may be regulated partly by the induction of ciliogenesis through Smo-GLI2 signaling.

  20. Near perfect optics

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

    Goeke, R.; Farnsworth, A.V.; Neumann, C.C.

    1996-06-01

    This report discusses a novel fabrication process to produce nearly perfect optics. The process utilizes vacuum deposition techniques to optimally modify polished optical substrate surfaces. The surface figure, i.e. contour of a polished optical element, is improved by differentially filling in the low spots on the surface using flux from a physical vapor deposition source through an appropriate mask. The process is expected to enable the manufacture of diffraction-limited optical systems for the UV, extreme UV, and soft X-ray spectral regions, which would have great impact on photolithography and astronomy. This same technique may also reduce the fabrication cost ofmore » visible region optics with aspheric surfaces.« less

  1. Optimization of coronagraph design for segmented aperture telescopes

    NASA Astrophysics Data System (ADS)

    Jewell, Jeffrey; Ruane, Garreth; Shaklan, Stuart; Mawet, Dimitri; Redding, Dave

    2017-09-01

    The goal of directly imaging Earth-like planets in the habitable zone of other stars has motivated the design of coronagraphs for use with large segmented aperture space telescopes. In order to achieve an optimal trade-off between planet light throughput and diffracted starlight suppression, we consider coronagraphs comprised of a stage of phase control implemented with deformable mirrors (or other optical elements), pupil plane apodization masks (gray scale or complex valued), and focal plane masks (either amplitude only or complex-valued, including phase only such as the vector vortex coronagraph). The optimization of these optical elements, with the goal of achieving 10 or more orders of magnitude in the suppression of on-axis (starlight) diffracted light, represents a challenging non-convex optimization problem with a nonlinear dependence on control degrees of freedom. We develop a new algorithmic approach to the design optimization problem, which we call the "Auxiliary Field Optimization" (AFO) algorithm. The central idea of the algorithm is to embed the original optimization problem, for either phase or amplitude (apodization) in various planes of the coronagraph, into a problem containing additional degrees of freedom, specifically fictitious "auxiliary" electric fields which serve as targets to inform the variation of our phase or amplitude parameters leading to good feasible designs. We present the algorithm, discuss details of its numerical implementation, and prove convergence to local minima of the objective function (here taken to be the intensity of the on-axis source in a "dark hole" region in the science focal plane). Finally, we present results showing application of the algorithm to both unobscured off-axis and obscured on-axis segmented telescope aperture designs. The application of the AFO algorithm to the coronagraph design problem has produced solutions which are capable of directly imaging planets in the habitable zone, provided end-to-end telescope system stability requirements can be met. Ongoing work includes advances of the AFO algorithm reported here to design in additional robustness to a resolved star, and other phase or amplitude aberrations to be encountered in a real segmented aperture space telescope.

  2. Cross-orientation masking in human color vision: application of a two-stage model to assess dichoptic and monocular sources of suppression.

    PubMed

    Kim, Yeon Jin; Gheiratmand, Mina; Mullen, Kathy T

    2013-05-28

    Cross-orientation masking (XOM) occurs when the detection of a test grating is masked by a superimposed grating at an orthogonal orientation, and is thought to reveal the suppressive effects mediating contrast normalization. Medina and Mullen (2009) reported that XOM was greater for chromatic than achromatic stimuli at equivalent spatial and temporal frequencies. Here we address whether the greater suppression found in binocular color vision originates from a monocular or interocular site, or both. We measure monocular and dichoptic masking functions for red-green color contrast and achromatic contrast at three different spatial frequencies (0.375, 0.75, and 1.5 cpd, 2 Hz). We fit these functions with a modified two-stage masking model (Meese & Baker, 2009) to extract the monocular and interocular weights of suppression. We find that the weight of monocular suppression is significantly higher for color than achromatic contrast, whereas dichoptic suppression is similar for both. These effects are invariant across spatial frequency. We then apply the model to the binocular masking data using the measured values of the monocular and interocular sources of suppression and show that these are sufficient to account for color binocular masking. We conclude that the greater strength of chromatic XOM has a monocular origin that transfers through to the binocular site.

  3. PMJ panel discussion overview on mask complexities, cost, and cycle time in 32-nm system LSI generation: conflict or concurrent?

    NASA Astrophysics Data System (ADS)

    Hosono, Kunihiro; Kato, Kokoro

    2008-10-01

    This is a report on a panel discussion organized in Photomask Japan 2008, where the challenges about "Mask Complexities, Cost, and Cycle Time in 32-nm System LSI Generation" were addressed to have a look over the possible solutions from the standpoints of chipmaker, commercial mask shop, DA tool vendor and equipments makers. The wrap-up is as follows: Mask complexities justify the mask cost, while the acceptable increase rate of 32nm-mask cost significantly differs between mask suppliers or users side. The efficiency progress by new tools or DFM has driven their cycle-time reductions. Mask complexities and cost will be crucial issues prior to cycle time, and there seems to be linear correlation between them. Controlling complexity and cycle time requires developing a mix of advanced technologies, and especially for cost reduction, shot prices in writers and processing rates in inspection tools have been improved remarkably by tool makers. In addition, activities of consortium in Japan (Mask D2I) are expected to enhance the total optimization of mask design, writing and inspection. The cycle-time reduction potentially drives the lowering of mask cost, and, on the other, the pattern complexities and tighter mask specifications get in the way to 32nm generation as well as the nano-economics and market challenges. There are still many difficult problems in mask manufacturing now, and we are sure to go ahead to overcome a 32nm hurdle with the advances of technologies and collaborations by not only technologies but also finance.

  4. Improved mask-based CD uniformity for gridded-design-rule lithography

    NASA Astrophysics Data System (ADS)

    Faivishevsky, Lev; Khristo, Sergey; Sagiv, Amir; Mangan, Shmoolik

    2009-03-01

    The difficulties encountered during lithography of state-of-the-art 2D patterns are formidable, and originate from the fact that deep sub-wavelength features are being printed. This results in a practical limit of k1 >=0.4 as well as a multitude of complex restrictive design rules, in order to mitigate or minimize lithographic hot spots. An alternative approach, that is gradually attracting the lithographic community's attention, restricts the design of critical layers to straight, dense lines (a 1D grid), that can be relatively easily printed using current lithographic technology. This is then followed by subsequent, less critical trimming stages to obtain circuit functionality. Thus, the 1D gridded approach allows hotspot-free, proximity-effect free lithography of ultra low- k1 features. These advantages must be supported by a stable CD control mechanism. One of the overriding parameters impacting CDU performance is photo mask quality. Previous publications have demonstrated that IntenCDTM - a novel, mask-based CDU mapping technology running on Applied Materials' Aera2TM aerial imaging mask inspection tool - is ideally fit for detecting mask-based CDU issues in 1D (L&S) patterned masks for memory production. Owing to the aerial nature of image formation, IntenCD directly probes the CD as it is printed on the wafer. In this paper we suggest that IntenCD is naturally fit for detecting mask-based CDU issues in 1D GDR masks. We then study a novel method of recovering and quantifying the physical source of printed CDU, using a novel implementation of the IntenCD technology. We demonstrate that additional, simple measurements, which can be readily performed on board the Aera2TM platform with minimal throughput penalty, may complement IntenCD and allow a robust estimation of the specific nature and strength of mask error source, such as pattern width variation or phase variation, which leads to CDU issues on the printed wafer. We finally discuss the roles played by IntenCD in advanced GDR mask production, starting with tight control over mask production process, continuing to mask qualification at mask shop and ending at in-line wafer CDU correction in fabs.

  5. Program and Project Management Framework

    NASA Technical Reports Server (NTRS)

    Butler, Cassandra D.

    2002-01-01

    The primary objective of this project was to develop a framework and system architecture for integrating program and project management tools that may be applied consistently throughout Kennedy Space Center (KSC) to optimize planning, cost estimating, risk management, and project control. Project management methodology used in building interactive systems to accommodate the needs of the project managers is applied as a key component in assessing the usefulness and applicability of the framework and tools developed. Research for the project included investigation and analysis of industrial practices, KSC standards, policies, and techniques, Systems Management Office (SMO) personnel, and other documented experiences of project management experts. In addition, this project documents best practices derived from the literature as well as new or developing project management models, practices, and techniques.

  6. Machine learning based detection of age-related macular degeneration (AMD) and diabetic macular edema (DME) from optical coherence tomography (OCT) images

    PubMed Central

    Wang, Yu; Zhang, Yaonan; Yao, Zhaomin; Zhao, Ruixue; Zhou, Fengfeng

    2016-01-01

    Non-lethal macular diseases greatly impact patients’ life quality, and will cause vision loss at the late stages. Visual inspection of the optical coherence tomography (OCT) images by the experienced clinicians is the main diagnosis technique. We proposed a computer-aided diagnosis (CAD) model to discriminate age-related macular degeneration (AMD), diabetic macular edema (DME) and healthy macula. The linear configuration pattern (LCP) based features of the OCT images were screened by the Correlation-based Feature Subset (CFS) selection algorithm. And the best model based on the sequential minimal optimization (SMO) algorithm achieved 99.3% in the overall accuracy for the three classes of samples. PMID:28018716

  7. Underwater acoustic positioning system for the SMO and KM3NeT - Italia projects

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

    Viola, S.; Barbagallo, G.; Cacopardo, G.

    In the underwater neutrino telescopes, the positions of the Cherenkov light sensors and their movements must be known with an accuracy of few tens of centimetres. In this work, the activities of the SMO and KM3NeT-Italia teams for the development of an acoustic positioning system for KM3NeT-Italia project are presented. The KM3NeT-Italia project foresees the construction, within two years, of 8 towers in the view of the several km{sup 3}-scale neutrino telescope KM3NeT.

  8. Diffractive phase-shift lithography photomask operating in proximity printing mode.

    PubMed

    Cirino, Giuseppe A; Mansano, Ronaldo D; Verdonck, Patrick; Cescato, Lucila; Neto, Luiz G

    2010-08-02

    A phase shift proximity printing lithographic mask is designed, manufactured and tested. Its design is based on a Fresnel computer-generated hologram, employing the scalar diffraction theory. The obtained amplitude and phase distributions were mapped into discrete levels. In addition, a coding scheme using sub-cells structure was employed in order to increase the number of discrete levels, thus increasing the degree of freedom in the resulting mask. The mask is fabricated on a fused silica substrate and an amorphous hydrogenated carbon (a:C-H) thin film which act as amplitude modulation agent. The lithographic image is projected onto a resist coated silicon wafer, placed at a distance of 50 microm behind the mask. The results show a improvement of the achieved resolution--linewidth as good as 1.5 microm--what is impossible to obtain with traditional binary masks in proximity printing mode. Such achieved dimensions can be used in the fabrication of MEMS and MOEMS devices. These results are obtained with a UV laser but also with a small arc lamp light source exploring the partial coherence of this source.

  9. Facial and ocular deposition of nebulized budesonide: effects of face mask design.

    PubMed

    Harris, Keith W; Smaldone, Gerald C

    2008-02-01

    In vivo case reports and in vitro studies have indicated that aerosol therapy using face masks can result in drug deposition on the face and in the eyes, and that face mask design may affect drug delivery. To test different mask/nebulizer combinations for budesonide, a nebulized steroid used to treat pediatric patients with asthma. Using high-performance liquid chromatography, drug delivery (inhaled mass), facial, and ocular deposition of budesonide aerosols were studied in vitro using a ventilated face facsimile (tidal volume, 50 mL; rate, 25 breaths/min, duty cycle 0.4), a tight-fitting test mask, a standard commercial mask, and a prototype mask designed to optimize delivery by reducing particle inertia. Nebulizer insertion into the mask (front loaded vs bottom loaded) was also tested. Particle size was measured by cascade impaction. Pari LC Plus (PARI Respiratory Equipment; Midlothian, VA) and MistyNeb (Allegiance; McGaw Park, IL) nebulizers were tested. Inhaled mass for tight-fitting and prototype masks was similar (13.2 +/- 1.85% vs 14.4 +/- 0.67% [percentage of nebulizer charge], p = 0.58) and significantly greater than for the commercial mask (3.03 +/- 0.26%, p = 0.005). Mask insertion of nebulizer was a key factor (inhaled mass: front loaded vs bottom loaded, 8.23 +/- 0.18% vs 3.03 +/- 0.26%; p = 0.005). Ocular deposition varied by an order of magnitude and was a strong function of mask design (4.77 +/- 0.24% vs 0.35 +/- 0.05%, p = 0.002, tight fitting vs prototype). Particle sizes (7.3 to 9 microm) were larger than previously reported for budesonide. For pediatric breathing patterns, mask design is a key factor defining budesonide delivery to the lungs, face, and eyes. Front-loaded nebulizer mask combinations are more efficient than bottom-loaded systems.

  10. Tracking the mutual shaping of the technical and social dimensions of solar-powered mosquito trapping systems (SMoTS) for malaria control on Rusinga Island, western Kenya.

    PubMed

    Oria, Prisca A; Hiscox, Alexandra; Alaii, Jane; Ayugi, Margaret; Mukabana, Wolfgang Richard; Takken, Willem; Leeuwis, Cees

    2014-11-18

    There has been increasing effort in recent years to incorporate user needs in technology design and re-design. This project employed a bottom-up approach that engaged end users from the outset. Bottom-up approaches have the potential to bolster novel interventions and move them towards adaptive and evidence-based strategies. The present study concerns an innovative use of solar-powered mosquito trapping systems (SMoTS) to control malaria in western Kenya. Our paper highlights the co-dependence of research associated with the development of the SMoTS technology on one hand and research for enhancing the sustainable uptake of that very same intervention within the community on the other. During the pre-intervention year, we examined the design, re-design and piloting of a novel technology to generate lessons for malaria elimination on Rusinga Island. Initial ideas about many technological necessities were evaluated and re-designed following feedback from various sources, including technical and social research as well as broader interactions with the social environment. We documented the interlocking of the multiple processes and activities that took place through process observation and document reviews. We analysed the data within the conceptual framework of system innovation by identifying mutual shaping between technical and social factors. Our findings illustrate how various project stakeholders including project staff, collaborators, donor, and community members simultaneously pursued interdependent technological transformations and social interests. In the ongoing process, we observed how partial outcomes in the technological domain influenced social events at a later phase and vice versa. Looking at malaria intervention projects employing novel technologies as niches that may evolve towards system innovation, helps to reveal interrelations between the various technical and social aspects. Revealing these interrelations requires a different role for research and different perspective on innovation where innovation is more than the technical aspects. This approach therefore requires that research is designed in a way that enables obtaining feedback from both aspects.

  11. Efficacy of a new device to optimize positive pressure ventilation via face mask in edentulous patients: a randomized trial.

    PubMed

    Niño, Maria C; Pauwels, Andres; Raffan, Fernando; Arango, Enrique; Romero, David J; Benitez, Daniel

    2017-04-01

    Mask ventilation is routinely performed during anesthesia. Under some circumstances, it might be difficult to perform, such as in edentulous patients, due to inadequate mask seal. We developed a new device called NIPARA and studied its use For ventilation optimization in edentulous patients. This randomized controlled trial included edentulous adults who had no other predictors of difficult airway, scheduled to undergo general anesthesia. Patients were assigned either to the NIPARA device group or to the control group (oral airway only). The primary outcomes were peak inspiratory pressure and tidal volume values of the first 14 breaths. The secondary outcome was the incidence of complications. Data from 37 patients were collected during a one-year period (twenty in the NIPARA device group and 17 in the control group). The difference in mean PIP was not statistically significant. The tidal volume was 1.5 times greater in the NIPARA group than in the control group. One patient from the intervention group had minimal oral trauma. In the administration of face mask ventilation, NIPARA is an effective device that significantly improves the tidal volume administered in edentulous patients.

  12. Development and Evaluation of Taste Masked Granular Formulation of Satranidazole by Melt Granulation Technique

    PubMed Central

    Pawar, Harshal Ashok; Joshi, Pooja Rasiklal

    2014-01-01

    Drugs from nitroimidazole category are generally bitter in taste. Oral formulation with bitter taste is not palatable. Geriatrics and pediatrics patients usually suffer from swallowing difficulties. Many other patients in some disease conditions avoid swallowing tablets. Satranidazole is a new nitro-imidazole derivative with bitter taste and is available in market as film coated tablet. The purpose of this research was to mask the bitter taste of Satranidazole by coating complexation with low melting point wax and Eudragit EPO. Different types of wax (glyceryl monostearate, stearic acid and cetyl alcohol) were tried for taste masking. The drug to stearic acid ratio 1 : 2 was found to be optimum on the basis of taste evaluation and in vitro release. The formulated granules were found to possess good flow property. FTIR studies confirmed that there was no interaction between drug and excipients. Scanning Electron Microscopy of drug and the optimized batch of granules was performed. The in vitro release of drug from granules was compared with marketed tablet formulation. The taste masked granules of optimized batch showed 87.65% release of drug in 1 hr which is comparable to that of marketed tablet formulation. PMID:26556200

  13. Fabrication of a novel quartz micromachined gyroscope

    NASA Astrophysics Data System (ADS)

    Xie, Liqiang; Xing, Jianchun; Wang, Haoxu; Wu, Xuezhong

    2015-04-01

    A novel quartz micromachined gyroscope is proposed in this paper. The novel gyroscope is realized by quartz anisotropic wet etching and 3-dimensional electrodes deposition. In the quartz wet etching process, the quality of Cr/Au mask films affecting the process are studied by experiment. An excellent mask film with 100 Å Cr and 2000 Å Au is achieved by optimization of experimental parameters. Crystal facets after etching seriously affect the following sidewall electrodes deposition process and the structure's mechanical behaviours. Removal of crystal facets is successfully implemented by increasing etching time based on etching rate ratios between facets and crystal planes. In the electrodes deposition process, an aperture mask evaporation method is employed to prepare electrodes on 3-dimensional surfaces of the gyroscope structure. The alignments among the aperture masks are realized by the ABM™ Mask Aligner System. Based on the processes described above, a z-axis quartz gyroscope is fabricated successfully.

  14. Secondary gamma-ray production in a coded aperture mask

    NASA Technical Reports Server (NTRS)

    Owens, A.; Frye, G. M., Jr.; Hall, C. J.; Jenkins, T. L.; Pendleton, G. N.; Carter, J. N.; Ramsden, D.; Agrinier, B.; Bonfand, E.; Gouiffes, C.

    1985-01-01

    The application of the coded aperture mask to high energy gamma-ray astronomy will provide the capability of locating a cosmic gamma-ray point source with a precision of a few arc-minutes above 20 MeV. Recent tests using a mask in conjunction with drift chamber detectors have shown that the expected point spread function is achieved over an acceptance cone of 25 deg. A telescope employing this technique differs from a conventional telescope only in that the presence of the mask modifies the radiation field in the vicinity of the detection plane. In addition to reducing the primary photon flux incident on the detector by absorption in the mask elements, the mask will also be a secondary radiator of gamma-rays. The various background components in a CAMTRAC (Coded Aperture Mask Track Chamber) telescope are considered. Monte-Carlo calculations are compared with recent measurements obtained using a prototype instrument in a tagged photon beam line.

  15. Condenser for photolithography system

    DOEpatents

    Sweatt, William C.

    2004-03-02

    A condenser for a photolithography system, in which a mask image from a mask is projected onto a wafer through a camera having an entrance pupil, includes a source of propagating radiation, a first mirror illuminated by the radiation, a mirror array illuminated by the radiation reflected from said first mirror, and a second mirror illuminated by the radiation reflected from the array. The mirror array includes a plurality of micromirrors. Each of the micromirrors is selectively actuatable independently of each other. The first mirror and the second mirror are disposed such that the source is imaged onto a plane of the mask and the mirror array is imaged into the entrance pupil of the camera.

  16. Observation of EUVL mask using coherent EUV scatterometry microscope with high-harmonic-generation EUV source

    NASA Astrophysics Data System (ADS)

    Mamezaki, Daiki; Harada, Tetsuo; Nagata, Yutaka; Watanabe, Takeo

    2017-07-01

    In extreme ultraviolet (EUV) lithography, development of review tools for EUV mask pattern and phase defect at working wavelength of 13.5 nm is required. The EUV mask is composed of an absorber pattern (50 - 70 nm thick) and Mo/Si multilayer (280 nm thick) on a glass substrate. This mask pattern seems three-dimensional (3D) structure. This 3D structure would modulate EUV reflection phase, which would cause focus and pattern shifts. Thus, EUV phase imaging is important to evaluate this phase modulation. We have developed coherent EUV scatterometry microscope (CSM), which is a simple microscope without objective optics. EUV phase and intensity image are reconstructed with diffraction images by ptychography with coherent EUV illumination. The high-harmonic-generation (HHG) EUV source was employed for standalone CSM system. In this study, we updated HHG system of pump-laser reduction and gas-pressure control. Two types of EUV mask absorber patterns were observed. An 88-nm lines-and-spaces and a cross-line patterns were clearly reconstructed by ptychography. In addition, a natural defect with 2-μm diameter on the cross-line was well reconstructed. This demonstrated the high capability of the standalone CSM, which system will be used in the factories, such as mask shops and semiconductor fabrication plants.

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

    Naulleau, Patrick

    With demonstrated resist resolution of 20 nm half pitch, the SEMATECH Berkeley BUV microfield exposure tool continues to push crucial advances in the areas of BUY resists and masks. The ever progressing shrink in computer chip feature sizes has been fueled over the years by a continual reduction in the wavelength of light used to pattern the chips. Recently, this trend has been threatened by unavailability of lens materials suitable for wavelengths shorter than 193 nm. To circumvent this roadblock, a reflective technology utilizing a significantly shorter extreme ultraviolet (EUV) wavelength (13.5 nm) has been under development for the pastmore » decade. The dramatic wavelength shrink was required to compensate for optical design limitations intrinsic in mirror-based systems compared to refractive lens systems. With this significant reduction in wavelength comes a variety of new challenges including developing sources of adequate power, photoresists with suitable resolution, sensitivity, and line-edge roughness characteristics, as well as the fabrication of reflection masks with zero defects. While source development can proceed in the absence of available exposure tools, in order for progress to be made in the areas of resists and masks it is crucial to have access to advanced exposure tools with resolutions equal to or better than that expected from initial production tools. These advanced development tools, however, need not be full field tools. Also, implementing such tools at synchrotron facilities allows them to be developed independent of the availability of reliable stand-alone BUY sources. One such tool is the SEMATECH Berkeley microfield exposure tool (MET). The most unique attribute of the SEMA TECH Berkeley MET is its use of a custom-coherence illuminator made possible by its implementation on a synchrotron beamline. With only conventional illumination and conventional binary masks, the resolution limit of the 0.3-NA optic is approximately 25 nm, however, with EUV not expected in production before the 22-nm half pitch node even finer resolution capabilities are now required from development tools. The SEMATECH Berkeley MET's custom-coherence illuminator allows it to be used with aggressive modified illumination enabling kJ factors as low as 0.25. Noting that the lithographic resolution of an exposure tool is defined as k{sub 1}{lambda}/NA, yielding an ultimate resolution limit of 11 nm. To achieve sub-20-nm aerial-image resolution while avoiding forbidden pitches on Manhattan-geometry features with the centrally-obscured MET optic, a 45-degree oriented dipole pupil fill is used. Figure 1 shows the computed aerial-image contrast as a function of half pitch for a dipole pupil fill optimized to print down to the 19-nm half pitch level. This is achieved with relatively uniform performance at larger dimensions. Using this illumination, printing down to the 20-nm half pitch level has been demonstrated in chemically amplified resists as shown in Fig. 2. The SEMATECH Berkeley MET tool plays a crucial role in the advancement of EUV resists. The unique programmable coherence properties of this tool enable it to achieve higher resolution than other EUV projection tools. As presented here, over the past year the tool has been used to demonstrate resist resolutions of 20 half pitch. Although not discussed here, because the Berkeley MET tool is a true projection lithography tool, it also plays a crucial role in advanced EUV mask research. Examples of the work done in this area include defect printability, mask architecture, and phase shift masks.« less

  18. Several organic parameters on underlying hazardous constituents list can not be measured at the universal treatment standards

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

    Johnson, H.C.

    1998-07-01

    The Idaho National Engineering and Environmental Laboratory (INEEL) has several permitted treatment, storage and disposal facilities. The INEEL Sample Management Office (SMO) conducts all analysis subcontracting activities for Department of Energy Environmental Management programs at the INEEL. In this role, the INEEL SMO has had the opportunity to subcontract the analyses of various wastes (including ash from an interim status incinerator) requesting a target analyte list equivalent to the constituents listed in 40 Code of Federal Regulations. These analyses are required to ensure that treated wastes do not contain underlying hazardous constituents (UHC) at concentrations greater than the universal treatmentmore » standards (UTS) prior to land disposal. The INEEL SMO has conducted a good-faith effort by negotiating with several commercial laboratories to identify the lowest possible quantitation and detection limits that can be achieved for the organic UHC analytes. The results of this negotiating effort has been the discovery that no single laboratory (currently under subcontract with the INEEL SMO) can achieve a detection level that is within an order of magnitude of the UTS for all organic parameters on a clean sample matrix (e.g., sand). This does not mean that there is no laboratory that can achieve the order of magnitude requirements for all organic UHCs on a clean sample matrix. The negotiations held to date indicate that it is likely that no laboratory can achieve the order of magnitude requirements for a difficult sample matrix (e.g., an incinerator ash). The authors suggest that the regulation needs to be revised to address the disparity between what is achievable in the laboratory and the regulatory levels required by the UTS.« less

  19. Development of the Coastal Storm Modeling System (CoSMoS) for predicting the impact of storms on high-energy, active-margin coasts

    USGS Publications Warehouse

    Barnard, Patrick; Maarten van Ormondt,; Erikson, Li H.; Jodi Eshleman,; Hapke, Cheryl J.; Peter Ruggiero,; Peter Adams,; Foxgrover, Amy C.

    2014-01-01

    The Coastal Storm Modeling System (CoSMoS) applies a predominantly deterministic framework to make detailed predictions (meter scale) of storm-induced coastal flooding, erosion, and cliff failures over large geographic scales (100s of kilometers). CoSMoS was developed for hindcast studies, operational applications (i.e., nowcasts and multiday forecasts), and future climate scenarios (i.e., sea-level rise + storms) to provide emergency responders and coastal planners with critical storm hazards information that may be used to increase public safety, mitigate physical damages, and more effectively manage and allocate resources within complex coastal settings. The prototype system, developed for the California coast, uses the global WAVEWATCH III wave model, the TOPEX/Poseidon satellite altimetry-based global tide model, and atmospheric-forcing data from either the US National Weather Service (operational mode) or Global Climate Models (future climate mode), to determine regional wave and water-level boundary conditions. These physical processes are dynamically downscaled using a series of nested Delft3D-WAVE (SWAN) and Delft3D-FLOW (FLOW) models and linked at the coast to tightly spaced XBeach (eXtreme Beach) cross-shore profile models and a Bayesian probabilistic cliff failure model. Hindcast testing demonstrates that, despite uncertainties in preexisting beach morphology over the ~500 km alongshore extent of the pilot study area, CoSMoS effectively identifies discrete sections of the coast (100s of meters) that are vulnerable to coastal hazards under a range of current and future oceanographic forcing conditions, and is therefore an effective tool for operational and future climate scenario planning.

  20. Vismodegib Exerts Targeted Efficacy Against Recurrent Sonic Hedgehog–Subgroup Medulloblastoma: Results From Phase II Pediatric Brain Tumor Consortium Studies PBTC-025B and PBTC-032

    PubMed Central

    Robinson, Giles W.; Orr, Brent A.; Wu, Gang; Gururangan, Sridharan; Lin, Tong; Qaddoumi, Ibrahim; Packer, Roger J.; Goldman, Stewart; Prados, Michael D.; Desjardins, Annick; Chintagumpala, Murali; Takebe, Naoko; Kaste, Sue C.; Rusch, Michael; Allen, Sariah J.; Onar-Thomas, Arzu; Stewart, Clinton F.; Fouladi, Maryam; Boyett, James M.; Gilbertson, Richard J.; Curran, Tom; Ellison, David W.; Gajjar, Amar

    2015-01-01

    Purpose Two phase II studies assessed the efficacy of vismodegib, a sonic hedgehog (SHH) pathway inhibitor that binds smoothened (SMO), in pediatric and adult recurrent medulloblastoma (MB). Patients and Methods Adult patients enrolled onto PBTC-025B and pediatric patients enrolled onto PBTC-032 were treated with vismodegib (150 to 300 mg/d). Protocol-defined response, which had to be sustained for 8 weeks, was confirmed by central neuroimaging review. Molecular tests to identify patterns of response and insensitivity were performed when tissue was available. Results A total of 31 patients were enrolled onto PBTC-025B, and 12 were enrolled onto PBTC-032. Three patients in PBTC-025B and one in PBTC-032, all with SHH-subgroup MB (SHH-MB), exhibited protocol-defined responses. Progression-free survival (PFS) was longer in those with SHH-MB than in those with non-SHH–MB, and prolonged disease stabilization occurred in 41% of patient cases of SHH-MB. Among those with SHH-MB, loss of heterozygosity of PTCH1 was associated with prolonged PFS, and diffuse staining of P53 was associated with reduced PFS. Whole-exome sequencing identified mutations in SHH genes downstream from SMO in four of four tissue samples from nonresponders and upstream of SMO in two of four patients with favorable responses. Conclusion Vismodegib exhibits activity against adult recurrent SHH-MB but not against recurrent non-SHH–MB. Inadequate accrual of pediatric patients precluded conclusions in this population. Molecular analyses support the hypothesis that SMO inhibitor activity depends on the genomic aberrations within the tumor. Such inhibitors should be advanced in SHH-MB studies; however, molecular and genomic work remains imperative to identify target populations that will truly benefit. PMID:26169613

  1. Widespread GLI expression but limited canonical hedgehog signaling restricted to the ductular reaction in human chronic liver disease

    PubMed Central

    Tirnitz-Parker, Janina Elke Eleonore; Hamson, Elizabeth Jane; Warren, Alessandra; Maneck, Bharvi; Chen, Jinbiao; Patkunanathan, Bramilla; Boland, Jade; Cheng, Robert; Shackel, Nicholas Adam; Seth, Devanshi; Bowen, David Geoffrey; Martelotto, Luciano Gastón; Watkins, D. Neil; McCaughan, Geoffrey William

    2017-01-01

    Canonical Hedgehog (Hh) signaling in vertebrate cells occurs following Smoothened activation/translocation into the primary cilia (Pc), followed by a GLI transcriptional response. Nonetheless, GLI activation can occur independently of the canonical Hh pathway. Using a murine model of liver injury, we previously identified the importance of canonical Hh signaling within the Pc+ liver progenitor cell (LPC) population and noted that SMO-independent, GLI-mediated signals were important in multiple Pc-ve GLI2+ intrahepatic populations. This study extends these observations to human liver tissue, and analyses the effect of GLI inhibition on LPC viability/gene expression. Human donor and cirrhotic liver tissue specimens were evaluated for SHH, GLI2 and Pc expression using immunofluorescence and qRT-PCR. Changes to viability and gene expression in LPCs in vitro were assessed following GLI inhibition. Identification of Pc (as a marker of canonical Hh signaling) in human cirrhosis was predominantly confined to the ductular reaction and LPCs. In contrast, GLI2 was expressed in multiple cell populations including Pc-ve endothelium, hepatocytes, and leukocytes. HSCs/myofibroblasts (>99%) expressed GLI2, with only 1.92% displaying Pc. In vitro GLI signals maintained proliferation/viability within LPCs and GLI inhibition affected the expression of genes related to stemness, hepatocyte/biliary differentiation and Hh/Wnt signaling. At least two mechanisms of GLI signaling (Pc/SMO-dependent and Pc/SMO-independent) mediate chronic liver disease pathogenesis. This may have significant ramifications for the choice of Hh inhibitor (anti-SMO or anti-GLI) suitable for clinical trials. We also postulate GLI delivers a pro-survival signal to LPCs whilst maintaining stemness. PMID:28187190

  2. Widespread GLI expression but limited canonical hedgehog signaling restricted to the ductular reaction in human chronic liver disease.

    PubMed

    Grzelak, Candice Alexandra; Sigglekow, Nicholas David; Tirnitz-Parker, Janina Elke Eleonore; Hamson, Elizabeth Jane; Warren, Alessandra; Maneck, Bharvi; Chen, Jinbiao; Patkunanathan, Bramilla; Boland, Jade; Cheng, Robert; Shackel, Nicholas Adam; Seth, Devanshi; Bowen, David Geoffrey; Martelotto, Luciano Gastón; Watkins, D Neil; McCaughan, Geoffrey William

    2017-01-01

    Canonical Hedgehog (Hh) signaling in vertebrate cells occurs following Smoothened activation/translocation into the primary cilia (Pc), followed by a GLI transcriptional response. Nonetheless, GLI activation can occur independently of the canonical Hh pathway. Using a murine model of liver injury, we previously identified the importance of canonical Hh signaling within the Pc+ liver progenitor cell (LPC) population and noted that SMO-independent, GLI-mediated signals were important in multiple Pc-ve GLI2+ intrahepatic populations. This study extends these observations to human liver tissue, and analyses the effect of GLI inhibition on LPC viability/gene expression. Human donor and cirrhotic liver tissue specimens were evaluated for SHH, GLI2 and Pc expression using immunofluorescence and qRT-PCR. Changes to viability and gene expression in LPCs in vitro were assessed following GLI inhibition. Identification of Pc (as a marker of canonical Hh signaling) in human cirrhosis was predominantly confined to the ductular reaction and LPCs. In contrast, GLI2 was expressed in multiple cell populations including Pc-ve endothelium, hepatocytes, and leukocytes. HSCs/myofibroblasts (>99%) expressed GLI2, with only 1.92% displaying Pc. In vitro GLI signals maintained proliferation/viability within LPCs and GLI inhibition affected the expression of genes related to stemness, hepatocyte/biliary differentiation and Hh/Wnt signaling. At least two mechanisms of GLI signaling (Pc/SMO-dependent and Pc/SMO-independent) mediate chronic liver disease pathogenesis. This may have significant ramifications for the choice of Hh inhibitor (anti-SMO or anti-GLI) suitable for clinical trials. We also postulate GLI delivers a pro-survival signal to LPCs whilst maintaining stemness.

  3. Thyroid Hormone Regulates the Expression of the Sonic Hedgehog Signaling Pathway in the Embryonic and Adult Mammalian Brain

    PubMed Central

    Desouza, Lynette A.; Sathanoori, Malini; Kapoor, Richa; Rajadhyaksha, Neha; Gonzalez, Luis E.; Kottmann, Andreas H.; Tole, Shubha

    2011-01-01

    Thyroid hormone is important for development and plasticity in the immature and adult mammalian brain. Several thyroid hormone-responsive genes are regulated during specific developmental time windows, with relatively few influenced across the lifespan. We provide novel evidence that thyroid hormone regulates expression of the key developmental morphogen sonic hedgehog (Shh), and its coreceptors patched (Ptc) and smoothened (Smo), in the early embryonic and adult forebrain. Maternal hypo- and hyperthyroidism bidirectionally influenced Shh mRNA in embryonic forebrain signaling centers at stages before fetal thyroid hormone synthesis. Further, Smo and Ptc expression were significantly decreased in the forebrain of embryos derived from hypothyroid dams. Adult-onset thyroid hormone perturbations also regulated expression of the Shh pathway bidirectionally, with a significant induction of Shh, Ptc, and Smo after hyperthyroidism and a decline in Smo expression in the hypothyroid brain. Short-term T3 administration resulted in a significant induction of cortical Shh mRNA expression and also enhanced reporter gene expression in Shh+/LacZ mice. Further, acute T3 treatment of cortical neuronal cultures resulted in a rapid and significant increase in Shh mRNA, suggesting direct effects. Chromatin immunoprecipitation assays performed on adult neocortex indicated enhanced histone acetylation at the Shh promoter after acute T3 administration, providing further support that Shh is a thyroid hormone-responsive gene. Our results indicate that maternal and adult-onset perturbations of euthyroid status cause robust and region-specific changes in the Shh pathway in the embryonic and adult forebrain, implicating Shh as a possible mechanistic link for specific neurodevelopmental effects of thyroid hormone. PMID:21363934

  4. Overactivation of hedgehog signaling alters development of the ovarian vasculature in mice.

    PubMed

    Ren, Yi; Cowan, Robert G; Migone, Fernando F; Quirk, Susan M

    2012-06-01

    The hedgehog (HH) signaling pathway is critical for ovarian function in Drosophila, but its role in the mammalian ovary has not been defined. Previously, expression of a dominant active allele of the HH signal transducer protein smoothened (SMO) in Amhr2(cre/+)SmoM2 mice caused anovulation in association with a lack of smooth muscle in the theca of developing follicles. The current study examined events during the first 2 wk of life in Amhr2(cre/+)SmoM2 mice to gain insight into the cause of anovulation. Expression of transcriptional targets of HH signaling, Gli1, Ptch1, and Hhip, which are used as measures of pathway activity, were elevated during the first several days of life in Amhr2(cre/+)SmoM2 mice compared to controls but were similar to controls in older mice. Microarray analysis showed that genes with increased expression in 2-day-old mutants compared to controls were enriched for the processes of vascular and tube development and steroidogenesis. The density of platelet endothelial cell adhesion molecule (PECAM)-labeled endothelial tubes was increased in the cortex of newborn ovaries of mutant mice. Costaining of preovulatory follicles for PECAM and smooth muscle actin showed that muscle-type vascular support cells are deficient in theca of mutant mice. Expression of genes for steroidogenic enzymes that are normally expressed in the fetal adrenal gland were elevated in newborn ovaries of mutant mice. In summary, overactivation of HH signaling during early life alters gene expression and vascular development and this is associated with the lifelong development of anovulatory follicles in which the thecal vasculature fails to mature appropriately.

  5. Overactivation of Hedgehog Signaling Alters Development of the Ovarian Vasculature in Mice1

    PubMed Central

    Ren, Yi; Cowan, Robert G.; Migone, Fernando F.; Quirk, Susan M.

    2012-01-01

    ABSTRACT The hedgehog (HH) signaling pathway is critical for ovarian function in Drosophila, but its role in the mammalian ovary has not been defined. Previously, expression of a dominant active allele of the HH signal transducer protein smoothened (SMO) in Amhr2cre/+SmoM2 mice caused anovulation in association with a lack of smooth muscle in the theca of developing follicles. The current study examined events during the first 2 wk of life in Amhr2cre/+SmoM2 mice to gain insight into the cause of anovulation. Expression of transcriptional targets of HH signaling, Gli1, Ptch1, and Hhip, which are used as measures of pathway activity, were elevated during the first several days of life in Amhr2cre/+SmoM2 mice compared to controls but were similar to controls in older mice. Microarray analysis showed that genes with increased expression in 2-day-old mutants compared to controls were enriched for the processes of vascular and tube development and steroidogenesis. The density of platelet endothelial cell adhesion molecule (PECAM)-labeled endothelial tubes was increased in the cortex of newborn ovaries of mutant mice. Costaining of preovulatory follicles for PECAM and smooth muscle actin showed that muscle-type vascular support cells are deficient in theca of mutant mice. Expression of genes for steroidogenic enzymes that are normally expressed in the fetal adrenal gland were elevated in newborn ovaries of mutant mice. In summary, overactivation of HH signaling during early life alters gene expression and vascular development and this is associated with the lifelong development of anovulatory follicles in which the thecal vasculature fails to mature appropriately. PMID:22402963

  6. Transcriptional profiles of SHH pathway genes in keratocystic odontogenic tumor and ameloblastoma.

    PubMed

    Gurgel, Clarissa Araújo Silva; Buim, Marcilei Eliza Cavichiolli; Carvalho, Kátia Cândido; Sales, Caroline Brandi Schlaepfer; Reis, Mitermayer Galvão; de Souza, Renata Oliveira; de Faro Valverde, Ludmila; de Azevedo, Roberto Almeida; Dos Santos, Jean Nunes; Soares, Fernando Augusto; Ramos, Eduardo Antônio Gonçalves

    2014-09-01

    Sonic hedgehog (SHH) pathway activation has been identified as a key factor in the development of many types of tumors, including odontogenic tumors. Our study examined the expression of genes in the SHH pathway to characterize their roles in the pathogenesis of keratocystic odontogenic tumors (KOT) and ameloblastomas (AB). We quantified the expression of SHH, SMO, PTCH1, SUFU, GLI1, CCND1, and BCL2 genes by qPCR in a total of 23 KOT, 11 AB, and three non-neoplastic oral mucosa (NNM). We also measured the expression of proteins related to this pathway (CCND1 and BCL2) by immunohistochemistry. We observed overexpression of SMO, PTCH1, GLI1, and CCND1 genes in both KOT (23/23) and AB (11/11). However, we did not detect expression of the SHH gene in 21/23 KOT and 10/11 AB tumors. Low levels of the SUFU gene were expressed in KOT (P = 0.0199) and AB (P = 0.0127) relative to the NNM. Recurrent KOT exhibited high levels of SMO (P = 0.035), PTCH1 (P = 0.048), CCND1 (P = 0.048), and BCL2 (P = 0.045) transcripts. Using immunolabeling of CCND1, we observed no statistical difference between primary and recurrent KOT (P = 0.8815), sporadic and NBCCS-KOT (P = 0.7688), and unicystic and solid AB (P = 0.7521). Overexpression of upstream (PTCH1 and SMO) and downstream (GLI1, CCND1 and BCL2) genes in the SHH pathway leads to the constitutive activation of this pathway in KOT and AB and may suggest a mechanism for the development of these types of tumors. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Beetroot-based gel supplementation improves handgrip strength, forearm muscle O2 saturation but not exercise tolerance and blood volume in jiu-jitsu athletes.

    PubMed

    de Oliveira, Gustavo Vieira; Nascimento, Luiz; Volino-Souza, Mônica; Mesquita, Jacilene; Alvares, Thiago

    2018-03-22

    The ergogenic effect of beetroot on the exercise performance of trained cyclists, runners, kayakers, and swimmers has been demonstrated. However, whether or not beetroot supplementation presents a beneficial effect on the exercise performance of jiu-jitsu athletes (JJA) remains inconclusive. Therefore, present study assessed the effect of beetroot-based gel (BG) supplementation on maximal voluntary contraction (MVC), exercise time until fatigue (ETF), muscle O2 saturation (SmO2), blood volume (tHb), and plasma nitrate and lactate in response to handgrip isotonic exercise (HIE) in JJA. In a randomized, crossover, double-blind design, 12 JJA performed three sets of HIE at 40% of the MVC until fatigue after 8 days (8th dose was offered 120 min previous exercise) of BG supplementation or a nitrate-depleted gel (PLA), and forearm SmO2 and tHb were continuously monitored by using near-infrared spectroscopy. Blood samples were taken before, immediately after exercise, and 20 min after exercise recovery in PLA and BG condition. MVC was evaluated at baseline and 20 min after HIE. There was a significant reduction in ∆MVC decline after HIE in BG condition. Forearm SmO2 during exercise recovery was significantly greater only after BG supplementation. No significant difference in ETF and tHb were observed between both BG and PLA in response to HIE. Plasma nitrate increased only after BG, whereas the exercise-induced increase in plasma lactate was significantly lower in BG when compared to PLA. In conclusion, BG supplementation may be a good nutritional strategy to improve forearm SmO2 and prevent force decline in response to exercise in JJA.

  8. Lithographic qualification of high-transmission mask blank for 10nm node and beyond

    NASA Astrophysics Data System (ADS)

    Xu, Yongan; Faure, Tom; Viswanathan, Ramya; Lobb, Granger; Wistrom, Richard; Burns, Sean; Hu, Lin; Graur, Ioana; Bleiman, Ben; Fischer, Dan; Mignot, Yann; Sakamoto, Yoshifumi; Toda, Yusuke; Bolton, John; Bailey, Todd; Felix, Nelson; Arnold, John; Colburn, Matthew

    2016-04-01

    In this paper, we discuss the lithographic qualification of high transmission (High T) mask for Via and contact hole applications in 10nm node and beyond. First, the simulated MEEF and depth of focus (DoF) data are compared between the 6% and High T attnPSM masks with the transmission of High T mask blank varying from 12% to 20%. The 12% High T blank shows significantly better MEEF and larger DoF than those of 6% attnPSM mask blank, which are consistent with our wafer data. However, the simulations show no obvious advantage in MEEF and DoF when the blank transmittance is larger than 12%. From our wafer data, it has been seen that the common process window from High T mask is 40nm bigger than that from the 6% attnPSM mask. In the elongated bar structure with smaller aspect ratio, 1.26, the 12% High T mask shows significantly less develop CD pull back in the major direction. Compared to the High T mask, the optimized new illumination condition for 6% attnPSM shows limited improvement in MEEF and the DoF through pitch. In addition, by using the High T mask blank, we have also investigated the SRAF printing, side lobe printing and the resist profile through cross sections, and no patterning risk has been found for manufacturing. As part of this work new 12% High T mask blank materials and processes were developed, and a brief overview of key mask technology development results have been shared. Overall, it is concluded that the High T mask, 12% transmission, provides the most robust and extendable lithographic solution for 10nm node and beyond.

  9. Manufacturability study of masks created by inverse lithography technology (ILT)

    NASA Astrophysics Data System (ADS)

    Martin, Patrick M.; Progler, C. J.; Xiao, G.; Gray, R.; Pang, L.; Liu, Y.

    2005-11-01

    As photolithography is pushed to fabricate deep-sub wavelength devices for 90nm, 65nm and smaller technology nodes using available exposure tools (i.e., 248nm, 193nm steppers), photomask capability is becoming extremely critical. For example, PSM masks require more complicated processing; aggressive OPC makes the writing time longer and sometimes unpredictable; and, high MEEF imposes much more stringent demands on mask quality. Therefore, in order for any new lithography technology to be adopted into production, mask manufacturability must be studied thoroughly and carefully. In this paper we will present the mask manufacturability study on mask patterns created using Inverse Lithography Technology (ILT). Unlike conventional OPC methodologies, ILT uses a unique outcome-based technology to mathematically determine the mask features that produce the desired on-wafer results. ILT solves the most critical litho challenges of the deep sub-wavelength era. Potential benefits include: higher yield; expanded litho process windows; superb pattern fidelity at 90, 65 & 45-nm nodes; and reduced time-to-silicon - all without changing the existing lithography infrastructure and design-to-silicon flow. In this study a number of cell structures were selected and used as test patterns. "Luminized patterns" were generated for binary mask and attenuated phase-shift mask. Both conventional OPC patterns and "luminized patterns" were put on a test reticle side by side, and they all have a number of variations in term of correction aggressivity level and mask complexity. Mask manufacturability, including data fracturing, writing time, mask inspection, and metrology were studied. The results demonstrate that, by optimizing the inspection recipe, masks created using ILT technology can be made and qualified using current processes with a reasonable turn-around time.

  10. Spectral identification of a 90Sr source in the presence of masking nuclides using Maximum-Likelihood deconvolution

    NASA Astrophysics Data System (ADS)

    Neuer, Marcus J.

    2013-11-01

    A technique for the spectral identification of strontium-90 is shown, utilising a Maximum-Likelihood deconvolution. Different deconvolution approaches are discussed and summarised. Based on the intensity distribution of the beta emission and Geant4 simulations, a combined response matrix is derived, tailored to the β- detection process in sodium iodide detectors. It includes scattering effects and attenuation by applying a base material decomposition extracted from Geant4 simulations with a CAD model for a realistic detector system. Inversion results of measurements show the agreement between deconvolution and reconstruction. A detailed investigation with additional masking sources like 40K, 226Ra and 131I shows that a contamination of strontium can be found in the presence of these nuisance sources. Identification algorithms for strontium are presented based on the derived technique. For the implementation of blind identification, an exemplary masking ratio is calculated.

  11. Extraction and utilization of the repeating patterns for CP writing in mask making

    NASA Astrophysics Data System (ADS)

    Shoji, Masahiro; Inoue, Tadao; Yamabe, Masaki

    2010-05-01

    In May 2006, the Mask Design, Drawing, and Inspection Technology Research Department (Mask D2I) at the Association of Super-Advanced Electronics Technologies (ASET) launched a 4-year program for reducing mask manufacturing cost and TAT by concurrent optimization of Mask Data Preparation (MDP), mask writing, and mask inspection [1]. Figure 1 shows an outline of the project at Mask D2I at ASET. As one of the tasks being pursued at the Mask Design Data Technology Research Laboratory we have evaluated the effect of reducing the writing shot counts by utilizing the repeating patterns, and that showed positive impact on mask making by using CP writing. During the past four years, we have developed a software to extract repeating patterns from fractured OPCed mask data and have evaluated the efficiency of reducing the writing shot counts using the repeating patterns with this software. In this evaluation, we have used many actual device production data obtained from the member companies of Mask D2I. To the extraction software, we added new functions for extracting common repeating patterns from a set of multiple masks, and studied how this step affects the ratio of reducing the shot counts in comparison to the case of utilization of the repeating patterns for single mask. We have also developed a software that uses the result of extracting repeating patterns and prepares writing-data for the MCC/CP writing system which has been developed at the Mask Writing Equipment Technology Research Laboratory. With this software, we have examined how EB proximity effect on CP writing affects in reducing the shot count where CP shots with large CD errors have to be divided into VSB shots. In this paper we will report on making common CP mask from a set of multiple actual device data by using these software, and will also report on the results of CP writing and calculation of writing-TAT by MCC/CP writing system.

  12. Integration of mask and silicon metrology in DFM

    NASA Astrophysics Data System (ADS)

    Matsuoka, Ryoichi; Mito, Hiroaki; Sugiyama, Akiyuki; Toyoda, Yasutaka

    2009-03-01

    We have developed a highly integrated method of mask and silicon metrology. The method adopts a metrology management system based on DBM (Design Based Metrology). This is the high accurate contouring created by an edge detection algorithm used in mask CD-SEM and silicon CD-SEM. We have inspected the high accuracy, stability and reproducibility in the experiments of integration. The accuracy is comparable with that of the mask and silicon CD-SEM metrology. In this report, we introduce the experimental results and the application. As shrinkage of design rule for semiconductor device advances, OPC (Optical Proximity Correction) goes aggressively dense in RET (Resolution Enhancement Technology). However, from the view point of DFM (Design for Manufacturability), the cost of data process for advanced MDP (Mask Data Preparation) and mask producing is a problem. Such trade-off between RET and mask producing is a big issue in semiconductor market especially in mask business. Seeing silicon device production process, information sharing is not completely organized between design section and production section. Design data created with OPC and MDP should be linked to process control on production. But design data and process control data are optimized independently. Thus, we provided a solution of DFM: advanced integration of mask metrology and silicon metrology. The system we propose here is composed of followings. 1) Design based recipe creation: Specify patterns on the design data for metrology. This step is fully automated since they are interfaced with hot spot coordinate information detected by various verification methods. 2) Design based image acquisition: Acquire the images of mask and silicon automatically by a recipe based on the pattern design of CD-SEM.It is a robust automated step because a wide range of design data is used for the image acquisition. 3) Contour profiling and GDS data generation: An image profiling process is applied to the acquired image based on the profiling method of the field proven CD metrology algorithm. The detected edges are then converted to GDSII format, which is a standard format for a design data, and utilized for various DFM systems such as simulation. Namely, by integrating pattern shapes of mask and silicon formed during a manufacturing process into GDSII format, it makes it possible to bridge highly accurate pattern profile information over to the design field of various EDA systems. These are fully integrated into design data and automated. Bi-directional cross probing between mask data and process control data is allowed by linking them. This method is a solution for total optimization that covers Design, MDP, mask production and silicon device producing. This method therefore is regarded as a strategic DFM approach in the semiconductor metrology.

  13. Barriers to mask wearing for influenza-like illnesses among urban Hispanic households.

    PubMed

    Ferng, Yu-hui; Wong-McLoughlin, Jennifer; Barrett, Angela; Currie, Leanne; Larson, Elaine

    2011-01-01

    To identify barriers to mask wearing and to examine the factors associated with the willingness to wear masks among households. We used data sources from a study assessing the impact of 3 nonpharmaceutical interventions on the rates of influenza: exit interviews; home visits with a subset of the mask group; and a focus group. Risk perception score, univariate analysis, and logistic regression were conducted to identify the characteristics and predictors of mask use. Thematic barriers to mask wearing were identified from qualitative data obtained at home visits and focus group. Respondents from the mask group, when compared with the nonmask group, demonstrated higher risk perception scores concerning influenza (maximum score: 60, means: 37.6 and 30.2, p<.001) and increased perception of effectiveness of mask wearing (maximum score: 10, means: 7.8 and 7.3, p=.043). There was no significant association between demographic, attitudinal, or knowledge variables and adherence to wearing masks. Thematic barriers were identified such as social acceptability of mask use, comfort and fit, and perception of the risk/need for masks. Face masks may not be an effective intervention for seasonal or pandemic influenza unless the risk perception of influenza is high. Dissemination of culturally appropriate mask use information by health authorities and providers must be emphasized when educating the public. © 2010 Wiley Periodicals, Inc.

  14. Silicon Solar Cell Optimization.

    DTIC Science & Technology

    1981-06-01

    from the surface. (b) Oxide mask formation Etching grooves into the silicon requires an effective alkaline-resistant mask which will withstand the...face. This technique employs a very viscous photoresist, Furt #206, in conjunction with multiple spin-applications and bake periods, to effectively ...175 80 125 78 75 74 To compare the effects of groove depth, substrate thick- ness and bulk resistivity, an experiment was conducted. Using identical

  15. An improved land mask for the SSM/I grid

    NASA Technical Reports Server (NTRS)

    Martino, Michael G.; Cavalieri, Donald J.; Gloersen, Per; Zwally, H. Jay; Acker, James G. (Editor)

    1995-01-01

    This paper discusses the development of a new land/ocean/coastline mask for use with Defense Meteorological Satellite Program (DMSP) Special Sensor Microwave/Imager (SSM/I) data, and other types of data which are mapped to the polar stereographic SSM/I grid. Pre-existing land masks were found to disagree, to lack certain land features, and to disagree with land boundaries that are visible in high resolution sensor imagery, such as imagery from the Synthetic Aperture Radar (SAR) on the Earth Resources Satellite (ERS-1). The Digital Chart of the World (DCW) database was initially selected as a source of shoreline data for this effort. Techniques for developing a land mask from these shoreline data are discussed. The resulting land mask, although not perfect, is seen to exhibit significant improvement over previous land mask products.

  16. ScAlN etch mask for highly selective silicon etching

    DOE PAGES

    Henry, Michael David; Young, Travis R.; Griffin, Ben

    2017-09-08

    Here, this work reports the utilization of a recently developed film, ScAlN, as a silicon etch mask offering significant improvements in high etch selectivity to silicon. Utilization of ScAlN as a fluorine chemistry based deep reactive ion etch mask demonstrated etch selectivity at 23 550:1, four times better than AlN, 11 times better than Al 2O 3, and 148 times better than silicon dioxide with significantly less resputtering at high bias voltage than either Al 2O 3 or AlN. Ellipsometry film thickness measurements show less than 0.3 nm/min mask erosion rates for ScAlN. Micromasking of resputtered Al for Al 2Omore » 3, AlN, and ScAlN etch masks is also reported here, utilizing cross-sectional scanning electron microscope and confocal microscope roughness measurements. With lower etch bias, the reduced etch rate can be optimized to achieve a trench bottom surface roughness that is comparable to SiO 2 etch masks. Etch mask selectivity enabled by ScAlN is likely to make significant improvements in microelectromechanical systems, wafer level packaging, and plasma dicing of silicon.« less

  17. Model of visual contrast gain control and pattern masking

    NASA Technical Reports Server (NTRS)

    Watson, A. B.; Solomon, J. A.

    1997-01-01

    We have implemented a model of contrast gain and control in human vision that incorporates a number of key features, including a contrast sensitivity function, multiple oriented bandpass channels, accelerating nonlinearities, and a devisive inhibitory gain control pool. The parameters of this model have been optimized through a fit to the recent data that describe masking of a Gabor function by cosine and Gabor masks [J. M. Foley, "Human luminance pattern mechanisms: masking experiments require a new model," J. Opt. Soc. Am. A 11, 1710 (1994)]. The model achieves a good fit to the data. We also demonstrate how the concept of recruitment may accommodate a variant of this model in which excitatory and inhibitory paths have a common accelerating nonlinearity, but which include multiple channels tuned to different levels of contrast.

  18. Umbra/penumbra detector

    DOEpatents

    Carner, Jr., Don C.

    1988-01-01

    A device which monitors the characteristics of an image cast upon a radiation sensitive substrate. This includes a shadow casting object or mask and at least one source of radiation disposed above the object or mask so that the image cast on the substrate can be analyzed.

  19. An economic analysis for optimal distributed computing resources for mask synthesis and tape-out in production environment

    NASA Astrophysics Data System (ADS)

    Cork, Chris; Lugg, Robert; Chacko, Manoj; Levi, Shimon

    2005-06-01

    With the exponential increase in output database size due to the aggressive optical proximity correction (OPC) and resolution enhancement technique (RET) required for deep sub-wavelength process nodes, the CPU time required for mask tape-out continues to increase significantly. For integrated device manufacturers (IDMs), this can impact the time-to-market for their products where even a few days delay could have a huge commercial impact and loss of market window opportunity. For foundries, a shorter turnaround time provides a competitive advantage in their demanding market, too slow could mean customers looking elsewhere for these services; while a fast turnaround may even command a higher price. With FAB turnaround of a mature, plain-vanilla CMOS process of around 20-30 days, a delay of several days in mask tapeout would contribute a significant fraction to the total time to deliver prototypes. Unlike silicon processing, masks tape-out time can be decreased by simply purchasing extra computing resources and software licenses. Mask tape-out groups are taking advantage of the ever-decreasing hardware cost and increasing power of commodity processors. The significant distributability inherent in some commercial Mask Synthesis software can be leveraged to address this critical business issue. Different implementations have different fractions of the code that cannot be parallelized and this affects the efficiency with which it scales, as is described by Amdahl"s law. Very few are efficient enough to allow the effective use of 1000"s of processors, enabling run times to drop from days to only minutes. What follows is a cost aware methodology to quantify the scalability of this class of software, and thus act as a guide to estimating the optimal investment in terms of hardware and software licenses.

  20. Sensorless sliding mode observer for a five-phase permanent magnet synchronous motor drive.

    PubMed

    Hosseyni, Anissa; Trabelsi, Ramzi; Mimouni, Med Faouzi; Iqbal, Atif; Alammari, Rashid

    2015-09-01

    This paper deals with the sensorless vector controlled five-phase permanent magnet synchronous motor (PMSM) drive based on a sliding mode observer (SMO). The observer is designed considering the back electromotive force (EMF) of five-phase permanent magnet synchronous motor. The SMO structure and design are illustrated. Stability of the proposed observer is demonstrated using Lyapunov stability criteria. The proposed strategy is asymptotically stable in the context of Lyapunov theory. Simulated results on a five-phase PMSM drive are displayed to validate the feasibility and the effectiveness of the proposed control strategy. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  1. Robust In-Flight Sensor Fault Diagnostics for Aircraft Engine Based on Sliding Mode Observers

    PubMed Central

    Chang, Xiaodong; Huang, Jinquan; Lu, Feng

    2017-01-01

    For a sensor fault diagnostic system of aircraft engines, the health performance degradation is an inevitable interference that cannot be neglected. To address this issue, this paper investigates an integrated on-line sensor fault diagnostic scheme for a commercial aircraft engine based on a sliding mode observer (SMO). In this approach, one sliding mode observer is designed for engine health performance tracking, and another for sensor fault reconstruction. Both observers are employed in in-flight applications. The results of the former SMO are analyzed for post-flight updating the baseline model of the latter. This idea is practical and feasible since the updating process does not require the algorithm to be regulated or redesigned, so that ground-based intervention is avoided, and the update process is implemented in an economical and efficient way. With this setup, the robustness of the proposed scheme to the health degradation is much enhanced and the latter SMO is able to fulfill sensor fault reconstruction over the course of the engine life. The proposed sensor fault diagnostic system is applied to a nonlinear simulation of a commercial aircraft engine, and its effectiveness is evaluated in several fault scenarios. PMID:28398255

  2. Robust In-Flight Sensor Fault Diagnostics for Aircraft Engine Based on Sliding Mode Observers.

    PubMed

    Chang, Xiaodong; Huang, Jinquan; Lu, Feng

    2017-04-11

    For a sensor fault diagnostic system of aircraft engines, the health performance degradation is an inevitable interference that cannot be neglected. To address this issue, this paper investigates an integrated on-line sensor fault diagnostic scheme for a commercial aircraft engine based on a sliding mode observer (SMO). In this approach, one sliding mode observer is designed for engine health performance tracking, and another for sensor fault reconstruction. Both observers are employed in in-flight applications. The results of the former SMO are analyzed for post-flight updating the baseline model of the latter. This idea is practical and feasible since the updating process does not require the algorithm to be regulated or redesigned, so that ground-based intervention is avoided, and the update process is implemented in an economical and efficient way. With this setup, the robustness of the proposed scheme to the health degradation is much enhanced and the latter SMO is able to fulfill sensor fault reconstruction over the course of the engine life. The proposed sensor fault diagnostic system is applied to a nonlinear simulation of a commercial aircraft engine, and its effectiveness is evaluated in several fault scenarios.

  3. Ground-based FTIR retrievals of SF6 on Reunion Island

    NASA Astrophysics Data System (ADS)

    Zhou, Minqiang; Langerock, Bavo; Vigouroux, Corinne; Wang, Pucai; Hermans, Christian; Stiller, Gabriele; Walker, Kaley A.; Dutton, Geoff; Mahieu, Emmanuel; De Mazière, Martine

    2018-02-01

    SF6 total columns were successfully retrieved from FTIR (Fourier transform infrared) measurements (Saint Denis and Maïdo) on Reunion Island (21° S, 55° E) between 2004 and 2016 using the SFIT4 algorithm: the retrieval strategy and the error budget were presented. The FTIR SF6 retrieval has independent information in only one individual layer, covering the whole of the troposphere and the lower stratosphere. The trend in SF6 was analysed based on the FTIR-retrieved dry-air column-averaged mole fractions (XSF6) on Reunion Island, the in situ measurements at America Samoa (SMO) and the collocated satellite measurements (Michelson Interferometer for Passive Atmospheric Sounding, MIPAS, and Atmospheric Chemistry Experiment Fourier Transform Spectrometer, ACE-FTS) in the southern tropics. The SF6 annual growth rate from FTIR retrievals is 0.265 ± 0.013 pptv year-1 for 2004-2016, which is slightly weaker than that from the SMO in situ measurements (0.285 ± 0.002 pptv year-1) for the same time period. The SF6 trend in the troposphere from MIPAS and ACE-FTS observations is also close to the ones from the FTIR retrievals and the SMO in situ measurements.

  4. Coatings masking in near, medium, and far infrared used for ship camouflage

    NASA Astrophysics Data System (ADS)

    Milewski, S.; Dulski, R.; Kastek, M.; Trzaskawka, P.; Barela, J.; Firmanty, K.

    2011-11-01

    The increasing range of naval engagements results in development of camouflages applied on warships that mask their signatures first in visible and next in and IR spectra. Camouflage applied on warships that mask their IR signatures is one of the most basic countermeasure methods against attacks by heat-seeking missiles. A set of special coatings applied to the ship's hull allows misidentification by enemies weapon and so make the ship harder to destroy. Thus the knowledge on actual thermal contrast between the ship and surrounding background is required in order to provide an effective antimissile defense. The paper presents selected aspects related to ship's camouflage realized by altering its thermal signature as well as the results of radiometric measurement of thermal radiation of IR-masking coatings. Measurements were performed using IR imaging spectrometers in near, medium and far infrared spectra. The presented measurement results constitute the basis for the assessment of the effectiveness of IR masking methods and additionally provide the opportunity to effectively simulate the properties of masking coatings and further to optimize their radiometric properties in the infrared range.

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

    Henry, Michael David; Young, Travis R.; Griffin, Ben

    Here, this work reports the utilization of a recently developed film, ScAlN, as a silicon etch mask offering significant improvements in high etch selectivity to silicon. Utilization of ScAlN as a fluorine chemistry based deep reactive ion etch mask demonstrated etch selectivity at 23 550:1, four times better than AlN, 11 times better than Al 2O 3, and 148 times better than silicon dioxide with significantly less resputtering at high bias voltage than either Al 2O 3 or AlN. Ellipsometry film thickness measurements show less than 0.3 nm/min mask erosion rates for ScAlN. Micromasking of resputtered Al for Al 2Omore » 3, AlN, and ScAlN etch masks is also reported here, utilizing cross-sectional scanning electron microscope and confocal microscope roughness measurements. With lower etch bias, the reduced etch rate can be optimized to achieve a trench bottom surface roughness that is comparable to SiO 2 etch masks. Etch mask selectivity enabled by ScAlN is likely to make significant improvements in microelectromechanical systems, wafer level packaging, and plasma dicing of silicon.« less

  6. The INTEGRAL scatterometer SPI

    NASA Technical Reports Server (NTRS)

    Mandrou, P.; Vedrenne, G.; Jean, P.; Kandel, B.; vonBallmoos, P.; Albernhe, F.; Lichti, G.; Schoenfelder, V.; Diehl, R.; Georgii, R.; hide

    1997-01-01

    The INTErnational Gamma Ray Astrophysics Laboratory (INTEGRAL) mission's onboard spectrometer, the INTEGRAL spectrometer (SPI), is described. The SPI constitutes one of the four main mission instruments. It is optimized for detailed measurements of gamma ray lines and for the mapping of diffuse sources. It combines a coded aperture mask with an array of large volume, high purity germanium detectors. The detectors make precise measurements of the gamma ray energies over the 20 keV to 8 MeV range. The instrument's characteristics are described and the Monte Carlo simulation of its performance is outlined. It will be possible to study gamma ray emission from compact objects or line profiles with a high energy resolution and a high angular resolution.

  7. Umbra/penumbra detector

    DOEpatents

    Carner, D.C. Jr.

    1988-10-11

    A device which monitors the characteristics of an image cast upon a radiation sensitive substrate. This includes a shadow casting object or mask and at least one source of radiation disposed above the object or mask so that the image cast on the substrate can be analyzed. 23 figs.

  8. Development of new FIB technology for EUVL mask repair

    NASA Astrophysics Data System (ADS)

    Aramaki, Fumio; Ogawa, Takashi; Matsuda, Osamu; Kozakai, Tomokazu; Sugiyama, Yasuhiko; Oba, Hiroshi; Yasaka, Anto; Amano, Tsuyoshi; Shigemura, Hiroyuki; Suga, Osamu

    2011-04-01

    The next generation EUVL masks beyond hp15nm are difficult to repair for the current repair technologies including focused ion beam (FIB) and electron beam (EB) in view of the minimum repairable size. We developed a new FIB technology to repair EUVL masks. Conventional FIB use gallium ions (Ga+) generated by a liquid metal ion source (LMIS), but the new FIB uses hydrogen ions (H2+) generated by a gas field ion source (GFIS). The minimum reaction area of H2+ FIB is theoretically much smaller than that of EB. We investigated the repair performance of H2+ FIB. In the concrete, we evaluated image resolution, scan damage, etching rate, material selectivity of etching and actinic image of repaired area. The most important result is that there was no difference between the repaired area and the non-repaired one on actinic images. That result suggests that the H2+ GFIS technology is a promising candidate for the solution to repair the next generation EUVL masks beyond hp15nm.

  9. Green clay and aloe vera peel-off facial masks: response surface methodology applied to the formulation design.

    PubMed

    O'Reilly Beringhs, André; Rosa, Julia Macedo; Stulzer, Hellen Karine; Budal, Rosane Maria; Sonaglio, Diva

    2013-03-01

    This article describes the optimization of a peel-off facial mask formulation. An investigation was carried out on the parameters of the formulation that most affect the desirable characteristics of peel-off facial masks. Cereal alcohol had a significant effect on the drying time at concentrations of 1-12% (w/w). The applicability of the evaluated formulations was influenced by both carbomer (0-2.4%; w/w) and polyvinyl alcohol (PVA; 2.5-17.5%; w/w) content due to their ability to alter the formulation viscosity. Inverse concentrations of carbomer and PVA led to formulations with optimum viscosity for facial application. Film-forming performance was influenced only by the PVA concentration, achieving maximum levels at concentrations of around 11% (w/w). The optimized formulation, determined mathematically, contained 13% (w/w) PVA and 10% (w/w) cereal alcohol with no addition of carbomer. This formulation provided high levels of applicability and film-forming performance, the lowest drying time possible and excellent homogeneity of the green clay particles and aloe vera before and after drying. The preliminary stability study indicated that the optimized formulation is stable under normal storage conditions. The microbiological stability evaluation indicated that the preservative was efficient in terms of avoiding microbial growth. RSM was shown to be a useful statistical tool for the determination of the behavior of different compounds and their concentrations for the responses studied, allowing the investigation of the optimum conditions for the production of green clay and aloe vera peel-off facial masks.

  10. Retrieve polarization aberration from image degradation: a new measurement method in DUV lithography

    NASA Astrophysics Data System (ADS)

    Xiang, Zhongbo; Li, Yanqiu

    2017-10-01

    Detailed knowledge of polarization aberration (PA) of projection lens in higher-NA DUV lithographic imaging is necessary due to its impact to imaging degradations, and precise measurement of PA is conductive to computational lithography techniques such as RET and OPC. Current in situ measurement method of PA thorough the detection of degradations of aerial images need to do linear approximation and apply the assumption of 3-beam/2-beam interference condition. The former approximation neglects the coupling effect of the PA coefficients, which would significantly influence the accuracy of PA retrieving. The latter assumption restricts the feasible pitch of test masks in higher-NA system, conflicts with the Kirhhoff diffraction model of test mask used in retrieving model, and introduces 3D mask effect as a source of retrieving error. In this paper, a new in situ measurement method of PA is proposed. It establishes the analytical quadratic relation between the PA coefficients and the degradations of aerial images of one-dimensional dense lines in coherent illumination through vector aerial imaging, which does not rely on the assumption of 3-beam/2- beam interference and linear approximation. In this case, the retrieval of PA from image degradation can be convert from the nonlinear system of m-quadratic equations to a multi-objective quadratic optimization problem, and finally be solved by nonlinear least square method. Some preliminary simulation results are given to demonstrate the correctness and accuracy of the new PA retrieving model.

  11. Melt-in-Mouth Multi-particulate System for the Treatment of ADHD: A Convenient Platform for Pediatric Use.

    PubMed

    Patadia, Jalashri; Tripathi, Rahul; Joshi, Amita

    2016-08-01

    Generally, pellets obtained from extrusion/spheronization, containing microcrystalline cellulose (MCC), do not disintegrate. An attempt has been made to develop melt-in-mouth pellets of taste-masked atomoxetine hydrochloride, using extrusion-spheronization, for pediatric patients. Melt-in-mouth pellets were prepared using extrusion-spheronization method and optimized using 3(3) FFD. MCC (X1, %), mannitol (X2, %) and Indion 414: Pharmaburst 500 ratio (X3, ratio) were the factors (independent variables) studied, whereas responses studied (dependent variables) were friability (Y1, %), yield (Y2, %) shape (Y3, roundness) in vitro disintegration time (Y4, seconds). The optimized formulation obtained from FFD was characterized for friability, shape and morphology, in vitro disintegration time, porosity, moisture uptake, in vitro release study and in vivo taste and disintegration time in healthy human volunteers. Randomized, two-treatment, two-sequence, two-period, single dose, crossover sensory evaluation study of taste-masked melt-in-mouth pellet was carried out in 10 healthy human subjects. A statistically significant polynomial mathematical relationship was generated between the factors and responses to obtain an optimized formulation. The optimized formulation was characterized (in vitro and in vivo) and exhibited a rapid drug release in vitro attributed to fast disintegration of pellets and high solubility of drug in 0.1 N HCl and buffer (pH 6.8). In vivo, 40% of volunteers ranked taste-masked optimized formulation as slightly bitter while 60% ranked it as no taste. The optimized pellets were conveniently administered in volunteers and exhibited rapid in-vivo disintegration in the oral cavity. Melt-in-mouth pellets can be a used as a platform technology for administering drugs to paediatric patients accurately and conveniently resulting in patient compliance.

  12. Dynamic mask for producing uniform or graded-thickness thin films

    DOEpatents

    Folta, James A [Livermore, CA

    2006-06-13

    A method for producing single layer or multilayer films with high thickness uniformity or thickness gradients. The method utilizes a moving mask which blocks some of the flux from a sputter target or evaporation source before it deposits on a substrate. The velocity and position of the mask is computer controlled to precisely tailor the film thickness distribution. The method is applicable to any type of vapor deposition system, but is particularly useful for ion beam sputter deposition and evaporation deposition; and enables a high degree of uniformity for ion beam deposition, even for near-normal incidence of deposition species, which may be critical for producing low-defect multilayer coatings, such as required for masks for extreme ultraviolet lithography (EUVL). The mask can have a variety of shapes, from a simple solid paddle shape to a larger mask with a shaped hole through which the flux passes. The motion of the mask can be linear or rotational, and the mask can be moved to make single or multiple passes in front of the substrate per layer, and can pass completely or partially across the substrate.

  13. The Sensitivity of Coded Mask Telescopes

    NASA Technical Reports Server (NTRS)

    Skinner, Gerald K.

    2008-01-01

    Simple formulae are often used to estimate the sensitivity of coded mask X-ray or gamma-ray telescopes, but t,hese are strictly only applicable if a number of basic assumptions are met. Complications arise, for example, if a grid structure is used to support the mask elements, if the detector spatial resolution is not good enough to completely resolve all the detail in the shadow of the mask or if any of a number of other simplifying conditions are not fulfilled. We derive more general expressions for the Poisson-noise-limited sensitivity of astronomical telescopes using the coded mask technique, noting explicitly in what circumstances they are applicable. The emphasis is on using nomenclature and techniques that result in simple and revealing results. Where no convenient expression is available a procedure is given which allows the calculation of the sensitivity. We consider certain aspects of the optimisation of the design of a coded mask telescope and show that when the detector spatial resolution and the mask to detector separation are fixed, the best source location accuracy is obtained when the mask elements are equal in size to the detector pixels.

  14. Effects of annealing temperature on the H2-sensing properties of Pd-decorated WO3 nanorods

    NASA Astrophysics Data System (ADS)

    Lee, Sangmin; Lee, Woo Seok; Lee, Jae Kyung; Hyun, Soong Keun; Lee, Chongmu; Choi, Seungbok

    2018-03-01

    The temperature of the post-annealing treatment carried out after noble metal deposition onto semiconducting metal oxides (SMOs) must be carefully optimized to maximize the sensing performance of the metal-decorated SMO sensors. WO3 nanorods were synthesized by thermal evaporation of WO3 powders and decorated with Pd nanoparticles using a sol-gel method, followed by an annealing process. The effects of the annealing temperature on the hydrogen gas-sensing properties of the Pd-decorated WO3 nanorods were then examined; the optimal annealing temperature, leading to the highest response of the WO3 nanorod sensor to H2, was determined to be 600 °C. Post-annealing at 600 °C resulted in nanorods with the highest surface area-to-volume ratio, as well as in the optimal size and the largest number of deposited Pd nanoparticles, leading to the highest response and the shortest response/recovery times toward H2. The improved H2-sensing performance of the Pd-decorated WO3 nanorod sensor, compared to a sensor based on pristine WO3 nanorods, is attributed to the enhanced catalytic activity, increased surface area-to-volume ratio, and higher amounts of surface defects.

  15. Optimized distributed computing environment for mask data preparation

    NASA Astrophysics Data System (ADS)

    Ahn, Byoung-Sup; Bang, Ju-Mi; Ji, Min-Kyu; Kang, Sun; Jang, Sung-Hoon; Choi, Yo-Han; Ki, Won-Tai; Choi, Seong-Woon; Han, Woo-Sung

    2005-11-01

    As the critical dimension (CD) becomes smaller, various resolution enhancement techniques (RET) are widely adopted. In developing sub-100nm devices, the complexity of optical proximity correction (OPC) is severely increased and applied OPC layers are expanded to non-critical layers. The transformation of designed pattern data by OPC operation causes complexity, which cause runtime overheads to following steps such as mask data preparation (MDP), and collapse of existing design hierarchy. Therefore, many mask shops exploit the distributed computing method in order to reduce the runtime of mask data preparation rather than exploit the design hierarchy. Distributed computing uses a cluster of computers that are connected to local network system. However, there are two things to limit the benefit of the distributing computing method in MDP. First, every sequential MDP job, which uses maximum number of available CPUs, is not efficient compared to parallel MDP job execution due to the input data characteristics. Second, the runtime enhancement over input cost is not sufficient enough since the scalability of fracturing tools is limited. In this paper, we will discuss optimum load balancing environment that is useful in increasing the uptime of distributed computing system by assigning appropriate number of CPUs for each input design data. We will also describe the distributed processing (DP) parameter optimization to obtain maximum throughput in MDP job processing.

  16. Utilizing Hierarchical Segmentation to Generate Water and Snow Masks to Facilitate Monitoring Change with Remotely Sensed Image Data

    NASA Technical Reports Server (NTRS)

    Tilton, James C.; Lawrence, William T.; Plaza, Antonio J.

    2006-01-01

    The hierarchical segmentation (HSEG) algorithm is a hybrid of hierarchical step-wise optimization and constrained spectral clustering that produces a hierarchical set of image segmentations. This segmentation hierarchy organizes image data in a manner that makes the image's information content more accessible for analysis by enabling region-based analysis. This paper discusses data analysis with HSEG and describes several measures of region characteristics that may be useful analyzing segmentation hierarchies for various applications. Segmentation hierarchy analysis for generating landwater and snow/ice masks from MODIS (Moderate Resolution Imaging Spectroradiometer) data was demonstrated and compared with the corresponding MODIS standard products. The masks based on HSEG segmentation hierarchies compare very favorably to the MODIS standard products. Further, the HSEG based landwater mask was specifically tailored to the MODIS data and the HSEG snow/ice mask did not require the setting of a critical threshold as required in the production of the corresponding MODIS standard product.

  17. ION PRODUCING MECHANISM

    DOEpatents

    Oppenheimer, F.F.

    1959-06-01

    A calutron ion source is described which masks the ends of the arc to provide a more stable beam from the middle portion. The masking is effected by milling the arc slit in a single sheet of material which is secured to the open face of the arc block. (T.R.H.)

  18. Undersampling strategies for compressed sensing accelerated MR spectroscopic imaging

    NASA Astrophysics Data System (ADS)

    Vidya Shankar, Rohini; Hu, Houchun Harry; Bikkamane Jayadev, Nutandev; Chang, John C.; Kodibagkar, Vikram D.

    2017-03-01

    Compressed sensing (CS) can accelerate magnetic resonance spectroscopic imaging (MRSI), facilitating its widespread clinical integration. The objective of this study was to assess the effect of different undersampling strategy on CS-MRSI reconstruction quality. Phantom data were acquired on a Philips 3 T Ingenia scanner. Four types of undersampling masks, corresponding to each strategy, namely, low resolution, variable density, iterative design, and a priori were simulated in Matlab and retrospectively applied to the test 1X MRSI data to generate undersampled datasets corresponding to the 2X - 5X, and 7X accelerations for each type of mask. Reconstruction parameters were kept the same in each case(all masks and accelerations) to ensure that any resulting differences can be attributed to the type of mask being employed. The reconstructed datasets from each mask were statistically compared with the reference 1X, and assessed using metrics like the root mean square error and metabolite ratios. Simulation results indicate that both the a priori and variable density undersampling masks maintain high fidelity with the 1X up to five-fold acceleration. The low resolution mask based reconstructions showed statistically significant differences from the 1X with the reconstruction failing at 3X, while the iterative design reconstructions maintained fidelity with the 1X till 4X acceleration. In summary, a pilot study was conducted to identify an optimal sampling mask in CS-MRSI. Simulation results demonstrate that the a priori and variable density masks can provide statistically similar results to the fully sampled reference. Future work would involve implementing these two masks prospectively on a clinical scanner.

  19. Implementation of random contact hole design with CPL mask by using IML technology

    NASA Astrophysics Data System (ADS)

    Hsu, Michael; Van Den Broeke, Doug; Hsu, Stephen; Chen, J. Fung; Shi, Xuelong; Corcoran, Noel; Yu, Linda

    2005-11-01

    The contact hole imaging is a very challenge task for the optical lithography process during IC manufacturing. Lots of RETs were proposed to improve the contrast of small opening hole. Scattering Bar (SB) OPC, together with optimized illumination, is no doubt one of the critical enablers for low k1 contact imaging. In this study, an effective model-based SB OPC based on IML technology is implemented for contact layer at 90nm, 65nm, and 45nm nodes. For our full-chip implementation flow, the first step is to determine the critical design area and then to proceed with NA and illumination optimization. Then, we selected the best NA in combination with optimum illumination via a Diffraction Optical Element (DOE). With optimized illumination, it is now possible to construct an interference map for the full-chip mask pattern. Utilizing the interference map, the model-based SB OPC is performed. Next, model OPC can be applied with the presence of SB for the entire chip. It is important to note that, for patterning at k1 near 0.35 or below, it may be necessary to include 3D mask effects with a high NA OPC model. With enhanced DOF by IML and immersion process, the low k1 production worthy contact process is feasible.

  20. Effects of noise levels and call types on the source levels of killer whale calls.

    PubMed

    Holt, Marla M; Noren, Dawn P; Emmons, Candice K

    2011-11-01

    Accurate parameter estimates relevant to the vocal behavior of marine mammals are needed to assess potential effects of anthropogenic sound exposure including how masking noise reduces the active space of sounds used for communication. Information about how these animals modify their vocal behavior in response to noise exposure is also needed for such assessment. Prior studies have reported variations in the source levels of killer whale sounds, and a more recent study reported that killer whales compensate for vessel masking noise by increasing their call amplitude. The objectives of the current study were to investigate the source levels of a variety of call types in southern resident killer whales while also considering background noise level as a likely factor related to call source level variability. The source levels of 763 discrete calls along with corresponding background noise were measured over three summer field seasons in the waters surrounding the San Juan Islands, WA. Both noise level and call type were significant factors on call source levels (1-40 kHz band, range of 135.0-175.7 dB(rms) re 1 [micro sign]Pa at 1 m). These factors should be considered in models that predict how anthropogenic masking noise reduces vocal communication space in marine mammals.

  1. EUVL masks: paving the path for commercialization

    NASA Astrophysics Data System (ADS)

    Mangat, Pawitter J. S.; Hector, Scott D.

    2001-09-01

    Optical projection lithography has been the principal vehicle of semiconductor manufacturing for more than 20 years and is marching aggressively to satisfy the needs of semiconductor manufacturers for 100nm devices. However, the complexity of optical lithography continues to increase as wavelength reduction continues to 157nm. Extreme Ultraviolet Lithography (EUVL), with wavelength from 13-14 nm, is evolving as a leading next generation lithography option for semiconductor industry to stay on the path laid by Moore's Law. Masks are a critical part of the success of any technology and are considered to be high risk both for optical lithography and NGL technologies for sub-100nm lithography. Two key areas of EUV mask fabrication are reflective multilayer deposition and absorber patterning. In the case of reflective multilayers, delivering defect free multilayers for mask blanks is the biggest challenge. Defect mitigation is being explored as a possible option to smooth the multilayer defects in addition to optimization of the deposition process to reduce defect density. The mask patterning process needs focus on the defect-free absorber stack patterning process, mask cleaning, inspection and repair. In addition, there is considerable effort to understand by simulations, the defect printability, thermal and mechanical distortions, and non-telecentric illumination, to mention a few. To protect the finished mask from defects added during use, a removable pellicle strategy combined with thermophoretic protection during exposure is being developed. Recent migration to square form factor using low thermal expansion material (LTEM) is advantageous as historical developments in optical masks can be applied to EUV mask patterning. This paper addresses recent developments in the EUV mask patterning and highlights critical manufacturing process controls needed to fabricate defect-free full field masks with CD and image placement specifications for sub-70nm node lithography. No technology can be implemented without establishing the commercial infrastructure. The rising cost seems to be a major issue affecting the technology development. With respect to mask fabrication for commercial availability, a virtual mask shop analysis is presented that indicates that the process cost for EUVL masks are comparable to the high end optical mask with a reasonable yield. However, the cost for setting up a new mask facility is considerably high.

  2. Auditory Masking Patterns in Bottlenose Dolphins from Anthropogenic and Natural Sound Sources

    DTIC Science & Technology

    2011-09-30

    in Comparative Psychoacoustics, Birkhäuser Verlag Basel, Switzerland. pp. 307-318. Erbe C. (2008) Critical ratios of beluga whales ( Delphinapterus ... leucas ) and masked signal duration. Journal of the Acoustical Society of America 124:2216-2223. Levitt H. (1971) Transformed up-down methods in

  3. Defining defect specifications to optimize photomask production and requalification

    NASA Astrophysics Data System (ADS)

    Fiekowsky, Peter

    2006-10-01

    Reducing defect repairs and accelerating defect analysis is becoming more important as the total cost of defect repairs on advanced masks increases. Photomask defect specs based on printability, as measured on AIMS microscopes has been used for years, but the fundamental defect spec is still the defect size, as measured on the photomask, requiring the repair of many unprintable defects. ADAS, the Automated Defect Analysis System from AVI is now available in most advanced mask shops. It makes the use of pure printability specs, or "Optimal Defect Specs" practical. This software uses advanced algorithms to eliminate false defects caused by approximations in the inspection algorithm, classify each defect, simulate each defect and disposition each defect based on its printability and location. This paper defines "optimal defect specs", explains why they are now practical and economic, gives a method of determining them and provides accuracy data.

  4. Atomic-scale distortion of optically activated Sm dopants identified with site-selective X-ray absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Ishii, Masashi; Crowe, Iain F.; Halsall, Matthew P.; Hamilton, Bruce; Hu, Yongfeng; Sham, Tsun-Kong; Harako, Susumu; Zhao, Xin-Wei; Komuro, Shuji

    2013-10-01

    The local structure of luminescent Sm dopants was investigated using an X-ray absorption fine-structure technique with X-ray-excited optical luminescence. Because this technique evaluates X-ray absorption from luminescence, only optically active sites are analyzed. The Sm L3 near-edge spectrum contains split 5d states and a shake-up transition that are specific to luminescent Sm. Theoretical calculations using cluster models identified an atomic-scale distortion that can reproduce the split 5d states. The model with C4v local symmetry and compressive bond length of Sm-O of a six-fold oxygen (SmO6) cluster is most consistent with the experimental results.

  5. Noncanonical Hedgehog Signaling

    PubMed Central

    Brennan, Donna; Chen, Xiaole; Cheng, Lan; Mahoney, My; Riobo, Natalia A.

    2012-01-01

    The notion of noncanonical hedgehog (Hh) signaling in mammals has started to receive support from numerous observations. By noncanonical, we refer to all those cellular and tissue responses to any of the Hh isoforms that are independent of transcriptional changes mediated by the Gli family of transcription factors. In this chapter, we discuss the most recent findings that suggest that Patched1 can regulate cell proliferation and apoptosis independently of Smoothened (Smo) and Gli and the reports that Smo modulates actin cytoskeleton-dependent processes such as fibroblast migration, endothelial cell tubulogenesis, axonal extension, and neurite formation by diverse mechanisms that exclude any involvement of Gli-dependent transcription. We also acknowledge the existence of less stronger evidence of noncanonical signaling in Drosophila. PMID:22391299

  6. Semiconductor metal oxide compounds based gas sensors: A literature review

    NASA Astrophysics Data System (ADS)

    Patil, Sunil Jagannath; Patil, Arun Vithal; Dighavkar, Chandrakant Govindrao; Thakare, Kashinath Shravan; Borase, Ratan Yadav; Nandre, Sachin Jayaram; Deshpande, Nishad Gopal; Ahire, Rajendra Ramdas

    2015-03-01

    This paper gives a statistical view about important contributions and advances on semiconductor metal oxide (SMO) compounds based gas sensors developed to detect the air pollutants such as liquefied petroleum gas (LPG), H2S, NH3, CO2, acetone, ethanol, other volatile compounds and hazardous gases. Moreover, it is revealed that the alloy/composite made up of SMO gas sensors show better gas response than their counterpart single component gas sensors, i.e., they are found to enhance the 4S characteristics namely speed, sensitivity, selectivity and stability. Improvement of such types of sensors used for detection of various air pollutants, which are reported in last two decades, is highlighted herein.

  7. Techniques for the analysis of data from coded-mask X-ray telescopes

    NASA Technical Reports Server (NTRS)

    Skinner, G. K.; Ponman, T. J.; Hammersley, A. P.; Eyles, C. J.

    1987-01-01

    Several techniques useful in the analysis of data from coded-mask telescopes are presented. Methods of handling changes in the instrument pointing direction are reviewed and ways of using FFT techniques to do the deconvolution considered. Emphasis is on techniques for optimally-coded systems, but it is shown that the range of systems included in this class can be extended through the new concept of 'partial cycle averaging'.

  8. Formulation and evaluation of sublingual tablets containing Sumatriptan succinate

    PubMed Central

    Prajapati, Shailesh T; Patel, Parth B; Patel, Chhagan N

    2012-01-01

    Objective: Sumatriptan succinate is a selective 5-hydroxytryptamine-1 receptor agonist effective in the acute treatment of migraine headaches, having low bioavailability of about 15% orally due to first-pass metabolism. The purpose of this research was to mask the intensely bitter taste of Sumatriptan succinate and to formulate fast-acting, taste-masked sublingual tablet formulation. Materials and Methods: Taste masking was performed by solid dispersion method with mannitol and ion exchange with Kyron T 114 because it releases the drug in salivary pH. The resultant batches were evaluated for in-vivo taste masking as well compatability study (Fourier transform infrared (FTIR) and differential scanning calorimetry (DSC)). For a better feel in the mouth, menthol and sweetener Na saccharine were added to the tablet formulation. The tablets were prepared by direct compression and evaluated for weight variation, thickness, friability, drug content, hardness, disintegration time, wetting time, in vitro drug release, and in vitro permeation study. Results and Discussion: Optimized batches disintegrated in vitro within 28-34 s. Maximum drug release could be achieved with in 10 min for the solid dispersion batches and 14-15 min for the ion-exchange batches with Kyron T 114. The optimized tablet formulation showed better taste and the formulated sublingual tablets may act as a potential alternate for the Sumatriptan succinate oral tablet. Conclusion: Sumatriptan succinate can be successfully taste-masked by both the solid dispersion method using mannitol by the melting method and Ion exchange resin with Kyron T114. It was also concluded that prepared formulation improve bioavailability by prevention of first pass metabolism. PMID:23373008

  9. A mask manufacturer's perspective on maskless lithography

    NASA Astrophysics Data System (ADS)

    Buck, Peter; Biechler, Charles; Kalk, Franklin

    2005-11-01

    Maskless Lithography (ML2) is again being considered for use in mainstream CMOS IC manufacturing. Sessions at technical conferences are being devoted to ML2. A multitude of new companies have been formed in the last several years to apply new concepts to breaking the throughput barrier that has in the past prevented ML2 from achieving the cost and cycle time performance necessary to become economically viable, except in rare cases. Has Maskless Lithography's (we used to call it "Direct Write Lithography") time really come? If so, what is the expected impact on the mask manufacturer and does it matter? The lithography tools used today in mask manufacturing are similar in concept to ML2 except for scale, both in throughput and feature size. These mask tools produce highly accurate lithographic images directly from electronic pattern files, perform multi-layer overlay, and mix-n-match across multiple tools, tool types and sites. Mask manufacturers are already accustomed to the ultimate low volume - one substrate per design layer. In order to achieve the economically required throughput, proposed ML2 systems eliminate or greatly reduce some of the functions that are the source of the mask writer's accuracy. Can these ML2 systems meet the demanding lithographic requirements without these functions? ML2 may eliminate the reticle but many of the processes and procedures performed today by the mask manufacturer are still required. Examples include the increasingly complex mask data preparation step and the verification performed to ensure that the pattern on the reticle is accurately representing the design intent. The error sources that are fixed on a reticle are variable with time on an ML2 system. It has been proposed that if ML2 is successful it will become uneconomical to be in the mask business - that ML2, by taking the high profit masks will take all profitability out of mask manufacturing and thereby endanger the entire semiconductor industry. Others suggest that a successful ML2 system solves the mask cost issue and thereby reduces the need and attractiveness of ML2. Are these concerns valid? In this paper we will present a perspective on maskless lithography from the considerable "direct write" experience of a mask manufacturer. We will examine the various business models proposed for ML2 insertion as well as the key technical challenges to achieving simultaneously the throughput and the lithographic quality necessary to become economically viable. We will consider the question of the economic viability of the mask industry in a post-ML2 world and will propose possible models where the mask industry can meaningfully participate.

  10. Masked priming effect reflects evidence accumulated by the prime.

    PubMed

    Kinoshita, Sachiko; Norris, Dennis

    2010-01-01

    In the same-different match task, masked priming is observed with the same responses but not different responses. Norris and Kinoshita's (2008) Bayesian reader account of masked priming explains this pattern based on the same principle as that explaining the absence of priming for nonwords in the lexical decision task. The pattern of priming follows from the way the model makes optimal decisions in the two tasks; priming does not depend on first activating the prime and then the target. An alternative explanation is in terms of a bias towards responding "same" that exactly counters the facilitatory effect of lexical access. The present study tested these two views by varying both the degree to which the prime predicts the response and the visibility of the prime. Unmasked primes produced effects expected from the view that priming is influenced by the degree to which the prime predicts the response. In contrast, with masked primes, the size of priming for the same response was completely unaffected by predictability. These results rule out response bias as an explanation of the absence of masked priming for different responses and, in turn, indicate that masked priming is not a consequence of automatic lexical access of the prime.

  11. Patterning of light-extraction nanostructures on sapphire substrates using nanoimprint and ICP etching with different masking materials.

    PubMed

    Chen, Hao; Zhang, Qi; Chou, Stephen Y

    2015-02-27

    Sapphire nanopatterning is the key solution to GaN light emitting diode (LED) light extraction. One challenge is to etch deep nanostructures with a vertical sidewall in sapphire. Here, we report a study of the effects of two masking materials (SiO2 and Cr) and different etching recipes (the reaction gas ratio, the reaction pressure and the inductive power) in a chlorine-based (BCl3 and Cl2) inductively coupled plasma (ICP) etching of deep nanopillars in sapphire, and the etching process optimization. The masking materials were patterned by nanoimprinting. We have achieved high aspect ratio sapphire nanopillar arrays with a much steeper sidewall than the previous etching methods. We discover that the SiO2 mask has much slower erosion rate than the Cr mask under the same etching condition, leading to the deep cylinder-shaped nanopillars (122 nm diameter, 200 nm pitch, 170 nm high, flat top, and a vertical sidewall of 80° angle), rather than the pyramid-shaped shallow pillars (200 nm based diameter, 52 nm height, and 42° sidewall) resulted by using Cr mask. The processes developed are scalable to large volume LED manufacturing.

  12. Protein-bound Polysaccharide-K Inhibits Hedgehog Signaling Through Down-regulation of MAML3 and RBPJ Transcription Under Hypoxia, Suppressing the Malignant Phenotype in Pancreatic Cancer.

    PubMed

    Yamasaki, Akio; Onishi, Hideya; Imaizumi, Akira; Kawamoto, Makoto; Fujimura, Akiko; Oyama, Yasuhiro; Katano, Mitsuo

    2016-08-01

    Hedgehog signaling is activated in pancreatic cancer and could be a therapeutic target. We previously demonstrated that recombination signal binding protein for immunoglobulin-kappa-J region (RBPJ) and mastermind-like 3 (MAML3) contribute to the hypoxia-induced up-regulation of Smoothened (SMO) transcription. We have also shown that protein-bound polysaccharide-K (PSK) could be effective for refractory pancreatic cancer that down-regulates SMO transcription under hypoxia. In this study, we evaluated whether the anticancer mechanism of PSK involves inhibiting RBPJ and MAML3 expression under hypoxia. PSK reduced SMO, MAML3 and RBPJ expression in pancreatic cancer cells under hypoxia. PSK also blocked RBPJ-induced invasiveness under hypoxia by inhibiting matrix metalloproteinase expression. Lastly, we showed that PSK attenuated RBPJ-induced proliferation both in vitro and in vivo. These results suggest that PSK suppresses Hedgehog signaling through down-regulation of MAML3 and RBPJ transcription under hypoxia, inhibiting the induction of a malignant phenotype in pancreatic cancer. Our results may lead to development of new treatments for refractory pancreatic cancer using PSK as a Hedgehog inhibitor. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  13. Mutations in the human SC4MOL gene encoding a methyl sterol oxidase cause psoriasiform dermatitis, microcephaly, and developmental delay

    PubMed Central

    He, Miao; Kratz, Lisa E.; Michel, Joshua J.; Vallejo, Abbe N.; Ferris, Laura; Kelley, Richard I.; Hoover, Jacqueline J.; Jukic, Drazen; Gibson, K. Michael; Wolfe, Lynne A.; Ramachandran, Dhanya; Zwick, Michael E.; Vockley, Jerry

    2011-01-01

    Defects in cholesterol synthesis result in a wide variety of symptoms, from neonatal lethality to the relatively mild dysmorphic features and developmental delay found in individuals with Smith-Lemli-Opitz syndrome. We report here the identification of mutations in sterol-C4-methyl oxidase–like gene (SC4MOL) as the cause of an autosomal recessive syndrome in a human patient with psoriasiform dermatitis, arthralgias, congenital cataracts, microcephaly, and developmental delay. This gene encodes a sterol-C4-methyl oxidase (SMO), which catalyzes demethylation of C4-methylsterols in the cholesterol synthesis pathway. C4-Methylsterols are meiosis-activating sterols (MASs). They exist at high concentrations in the testis and ovary and play roles in meiosis activation. In this study, we found that an accumulation of MASs in the patient led to cell overproliferation in both skin and blood. SMO deficiency also substantially altered immunocyte phenotype and in vitro function. MASs serve as ligands for liver X receptors α and β (LXRα and LXRβ), which are important in regulating not only lipid transport in the epidermis, but also innate and adaptive immunity. Deficiency of SMO represents a biochemical defect in the cholesterol synthesis pathway, the clinical spectrum of which remains to be defined. PMID:21285510

  14. Basal cell carcinoma pathogenesis and therapy involving hedgehog signaling and beyond.

    PubMed

    Bakshi, Anshika; Chaudhary, Sandeep C; Rana, Mehtab; Elmets, Craig A; Athar, Mohammad

    2017-12-01

    Basal cell carcinoma (BCC) of the skin is driven by aberrant hedgehog signaling. Thus blocking this signaling pathway by small molecules such as vismodegib inhibits tumor growth. Primary cilium in the epidermal cells plays an integral role in the processing of hedgehog signaling-related proteins. Recent genomic studies point to the involvement of additional genetic mutations that might be associated with the development of BCCs, suggesting significance of other signaling pathways, such as WNT, NOTCH, mTOR, and Hippo, aside from hedgehog in the pathogenesis of this human neoplasm. Some of these pathways could be regulated by noncoding microRNA. Altered microRNA expression profile is recognized with the progression of these lesions. Stopping treatment with Smoothened (SMO) inhibitors often leads to tumor reoccurrence in the patients with basal cell nevus syndrome, who develop 10-100 of BCCs. In addition, the initial effectiveness of these SMO inhibitors is impaired due to the onset of mutations in the drug-binding domain of SMO. These data point to a need to develop strategies to overcome tumor recurrence and resistance and to enhance efficacy by developing novel single agent-based or multiple agents-based combinatorial approaches. Immunotherapy and photodynamic therapy could be additional successful approaches particularly if developed in combination with chemotherapy for inoperable and metastatic BCCs. © 2017 Wiley Periodicals, Inc.

  15. Basal cell carcinoma pathogenesis and therapy involving hedgehog signaling and beyond

    PubMed Central

    Bakshi, Anshika; Chaudhary, Sandeep C.; Rana, Mehtab; Elmets, Craig A.; Athar, Mohammad

    2018-01-01

    Basal cell carcinoma (BCC) of the skin is driven by aberrant hedgehog signaling. Thus blocking this signaling pathway by small molecules such as vismodegib inhibits tumor growth. Primary cilium in the epidermal cells plays an integral role in the processing of hedgehog signaling-related proteins. Recent genomic studies point to the involvement of additional genetic mutations that might be associated with the development of BCCs, suggesting significance of other signaling pathways, such as WNT, NOTCH, mTOR, and Hippo, aside from hedgehog in the pathogenesis of this human neoplasm. Some of these pathways could be regulated by noncoding microRNA. Altered microRNA expression profile is recognized with the progression of these lesions. Stopping treatment with Smoothened (SMO) inhibitors often leads to tumor reoccurrence in the patients with basal cell nevus syndrome, who develop 10–100 of BCCs. In addition, the initial effectiveness of these SMO inhibitors is impaired due to the onset of mutations in the drug-binding domain of SMO. These data point to a need to develop strategies to overcome tumor recurrence and resistance and to enhance efficacy by developing novel single agent-based or multiple agents-based combinatorial approaches. Immunotherapy and photodynamic therapy could be additional successful approaches particularly if developed in combination with chemotherapy for inoperable and metastatic BCCs. PMID:28574612

  16. Imaging performance improvement of coherent extreme-ultraviolet scatterometry microscope with high-harmonic-generation extreme-ultraviolet source

    NASA Astrophysics Data System (ADS)

    Mamezaki, Daiki; Harada, Tetsuo; Nagata, Yutaka; Watanabe, Takeo

    2017-06-01

    In extreme-ultraviolet (EUV) lithography, the development of a review apparatus for the EUV mask pattern at an exposure wavelength of 13.5 nm is required. The EUV mask is composed of an absorber pattern and a Mo/Si multilayer on a glass substrate. This mask pattern has a three-dimensional (3D) structure. The 3D structure would modulate the EUV reflection phase, which would cause focus and pattern shifts. Thus, the review of the EUV phase image is also important. We have developed a coherent EUV scatterometry microscope (CSM), which is a simple microscope without objective optics. The EUV phase and intensity images were reconstructed with diffraction images by ptychography. For a standalone mask review, the high-harmonic-generation (HHG) EUV source was employed. In this study, we updated the sample stage, pump-laser reduction system, and gas-pressure control system to reconstruct the image. As a result, an 88 nm line-and-space pattern and a cross-line pattern were reconstructed. In addition, a particle defect of 2 µm diameter was well reconstructed. This demonstrated the high capability of the standalone CSM, which can hence be used in factories, such as mask shops and semiconductor fabrication plants.

  17. Use of an Innovative Personality-Mindset Profiling Tool to Guide Culture-Change Strategies among Different Healthcare Worker Groups

    PubMed Central

    Grayson, M. Lindsay; Macesic, Nenad; Huang, G. Khai; Bond, Katherine; Fletcher, Jason; Gilbert, Gwendolyn L.; Gordon, David L.; Hellsten, Jane F.; Iredell, Jonathan; Keighley, Caitlin; Stuart, Rhonda L.; Xuereb, Charles S.; Cruickshank, Marilyn

    2015-01-01

    Introduction Important culture-change initiatives (e.g. improving hand hygiene compliance) are frequently associated with variable uptake among different healthcare worker (HCW) categories. Inherent personality differences between these groups may explain change uptake and help improve future intervention design. Materials and Methods We used an innovative personality-profiling tool (ColourGrid®) to assess personality differences among standard HCW categories at five large Australian hospitals using two data sources (HCW participant surveys [PS] and generic institution-wide human resource [HR] data) to: a) compare the relative accuracy of these two sources; b) identify differences between HCW groups and c) use the observed profiles to guide design strategies to improve uptake of three clinically-important initiatives (improved hand hygiene, antimicrobial stewardship and isolation procedure adherence). Results Results from 34,243 HCWs (HR data) and 1045 survey participants (PS data) suggest that HCWs were different from the general population, displaying more individualism, lower power distance, less uncertainty avoidance and greater cynicism about advertising messages. HR and PS data were highly concordant in identifying differences between the three key HCW categories (doctors, nursing/allied-health, support services) and predicting appropriate implementation strategies. Among doctors, the data suggest that key messaging should differ between full-time vs part-time (visiting) senior medical officers (SMO, VMO) and junior hospital medical officers (HMO), with SMO messaging focused on evidence-based compliance, VMO initiatives emphasising structured mandatory controls and prestige loss for non-adherence, and for HMOs focusing on leadership opportunity and future career risk for non-adherence. Discussion Compared to current standardised approaches, targeted interventions based on personality differences between HCW categories should result in improved infection control-related culture-change uptake. Personality profiling based on HR data may represent a useful means of developing a national culture-change “blueprint” for HCW education. PMID:26489012

  18. Attenuation of harmonic noise in vibroseis data using Simulated Annealing

    NASA Astrophysics Data System (ADS)

    Sharma, S. P.; Tildy, Peter; Iranpour, Kambiz; Scholtz, Peter

    2009-04-01

    Processing of high productivity vibroseis seismic data (such as slip-sweep acquisition records) suffers from the well known disadvantage of harmonic distortion. Harmonic distortions are observed after cross-correlation of the recorded seismic signal with the pilot sweep and affect the signals in negative time (before the actual strong reflection event). Weak reflection events of the earlier sweeps falling in the negative time window of the cross-correlation sequence are being masked by harmonic distortions. Though the amplitude of the harmonic distortion is small (up to 10-20 %) compared to the fundamental amplitude of the reflection events, but it is significant enough to mask weak reflected signals. Elimination of harmonic noise due to source signal distortion from the cross-correlated seismic trace is a challenging task since the application of vibratory sources started and it still needs improvement. An approach has been worked out that minimizes the level of harmonic distortion by designing the signal similar to the harmonic distortion. An arbitrary length filter is optimized using the Simulated Annealing global optimization approach to design a harmonic signal. The approach deals with the convolution of a ratio trace (ratio of the harmonics with respect to the fundamental sweep) with the correlated "positive time" recorded signal and an arbitrary filter. Synthetic data study has revealed that this procedure of designing a signal similar to the desired harmonics using convolution of a suitable filter with theoretical ratio of harmonics with fundamental sweep helps in reducing the problem of harmonic distortion. Once we generate a similar signal for a vibroseis source using an optimized filter, then, this filter could be used to generate harmonics, which can be subtracted from the main cross-correlated trace to get the better, undistorted image of the subsurface. Designing the predicted harmonics to reduce the energy in the trace by considering weak reflection and observed harmonics together yields the desired result (resolution of weak reflected signal from the harmonic distortion). As optimization steps proceeds forward it is possible to observe from the difference plots of desired and predicted harmonics how weak reflections evolved from the harmonic distortion gradually during later iterations of global optimization. The procedure is applied in resolving weak reflections from a number of traces considered together. For a more precise design of harmonics SA procedure needs longer computation time which is impractical to deal with voluminous seismic data. However, the objective of resolving weak reflection signal in the strong harmonic noise can be achieved with fast computation using faster cooling schedule and less number of iterations and number of moves in simulated annealing procedure. This process could help in reducing the harmonics distortion and achieving the objective of resolving the lost weak reflection events in the cross-correlated seismic traces. Acknowledgements: The research was supported under the European Marie Curie Host Fellowships for Transfer of Knowledge (TOK) Development Host Scheme (contract no. MTKD-CT-2006-042537).

  19. Dry etching technologies for the advanced binary film

    NASA Astrophysics Data System (ADS)

    Iino, Yoshinori; Karyu, Makoto; Ita, Hirotsugu; Yoshimori, Tomoaki; Azumano, Hidehito; Muto, Makoto; Nonaka, Mikio

    2011-11-01

    ABF (Advanced Binary Film) developed by Hoya as a photomask for 32 (nm) and larger specifications provides excellent resistance to both mask cleaning and 193 (nm) excimer laser and thereby helps extend the lifetime of the mask itself compared to conventional photomasks and consequently reduces the semiconductor manufacturing cost [1,2,3]. Because ABF uses Ta-based films, which are different from Cr film or MoSi films commonly used for photomask, a new process is required for its etching technology. A patterning technology for ABF was established to perform the dry etching process for Ta-based films by using the knowledge gained from absorption layer etching for EUV mask that required the same Ta-film etching process [4]. Using the mask etching system ARES, which is manufactured by Shibaura Mechatronics, and its optimized etching process, a favorable CD (Critical Dimension) uniformity, a CD linearity and other etching characteristics were obtained in ABF patterning. Those results are reported here.

  20. [Thermoplastic mask in radiotherapy: a source of anxiety for the patient?].

    PubMed

    Arino, C; Stadelmaier, N; Dupin, C; Kantor, G; Henriques de Figueiredo, B

    2014-12-01

    The thermoplastic mask often used to immobilize patients in radiotherapy can cause varying levels of stress and anxiety. This study aimed at evaluating the anxiety related to the use of radiotherapy masks and the coping strategies adopted by patients. Nineteen patients treated with radiotherapy mask for head and neck cancer, a brain tumour or a lymphoma, were met twice by a psychologist, either after the making of the mask and the first course of radiotherapy, or in the middle and at the end of treatment. Thirty-four semi-structured interviews were treated using a thematic content analysis and 13 patients answered to anxiety (STAI-YB) and coping (WCC) scales. The STAI-YB anxiety scores related to wearing the masks were low during the radiotherapy treatment period, and were confirmed by the remarks of patients recorded during the semi-structured interviews. Most patients had a positive perception of the mask, and considered it as a friend or protection. Twelve out of the 13 patients admitting to anxiety benefited from problem focused coping strategies. Thermoplastic mask-related anxiety is low and possibly lies in the positive representation patients have about the mask. The explanations provided by health professionals on the radiotherapy mask possibly have a very positive effect on this perception. Copyright © 2014 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  1. The oxidation of alkylaryl sulfides and benzo[b]thiophenes by Escherichia coli cells expressing wild-type and engineered styrene monooxygenase from Pseudomonas putida CA-3.

    PubMed

    Nikodinovic-Runic, Jasmina; Coulombel, Lydie; Francuski, Djordje; Sharma, Narain D; Boyd, Derek R; Ferrall, Rory Moore O; O'Connor, Kevin E

    2013-06-01

    Nine different sulfur-containing compounds were biotransformed to the corresponding sulfoxides by Escherichia coli Bl21(DE3) cells expressing styrene monooxygenase (SMO) from Pseudomonas putida CA-3. Thioanisole was consumed at 83.3 μmoles min(-1) g cell dry weight(-1) resulting mainly in the formation of R-thioanisole sulfoxide with an enantiomeric excess (ee) value of 45 %. The rate of 2-methyl-, 2-chloro- and 2-bromo-thioanisole consumption was 2-fold lower than that of thioanisole. Surprisingly, the 2-methylthioanisole sulfoxide product had the opposite (S) configuration to that of the other 2-substituted thioanisole derivatives and had a higher ee value (84 %). The rate of oxidation of 4-substituted thioanisoles was higher than the corresponding 2-substituted substrates but the ee values of the products were consistently lower (10-23 %). The rate of benzo[b]thiophene and 2-methylbenzo[b]thiophene sulfoxidation was approximately 10-fold lower than that of thioanisole. The ee value of the benzo[b]thiophene sulfoxide could not be determined as the product racemized rapidly. E. coli cells expressing an engineered SMO (SMOeng R3-11) oxidised 2-substituted thioanisoles between 1.8- and 2.8-fold faster compared to cells expressing the wild-type enzyme. SMOeng R3-11 oxidised benzo[b]thiophene and 2-methylbenzo[b]thiophene 10.1 and 5.6 times faster that the wild-type enzyme. The stereospecificity of the reaction catalysed by SMOeng was unchanged from that of the wild type. Using the X-ray crystal structure of the P. putida S12 SMO, it was evident that the entrance of substrates into the SMO active site is limited by the binding pocket bottleneck formed by the side chains of Val-211 and Asn-46 carboxyamide group.

  2. An orbital angular momentum radio communication system optimized by intensity controlled masks effectively: Theoretical design and experimental verification

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

    Gao, Xinlu; Applied Optics Beijing Area Major Laboratory, Department of Physics, Beijing Normal University, Beijing 100875; Huang, Shanguo, E-mail: shghuang@bupt.edu.cn

    A system of generating and receiving orbital angular momentum (OAM) radio beams, which are collectively formed by two circular array antennas (CAAs) and effectively optimized by two intensity controlled masks, is proposed and experimentally investigated. The scheme is effective in blocking of the unwanted OAM modes and enhancing the power of received radio signals, which results in the capacity gain of system and extended transmission distance of the OAM radio beams. The operation principle of the intensity controlled masks, which can be regarded as both collimator and filter, is feasible and simple to realize. Numerical simulations of intensity and phasemore » distributions at each key cross-sectional plane of the radio beams demonstrate the collimated results. The experimental results match well with the theoretical analysis and the receive distance of the OAM radio beam at radio frequency (RF) 20 GHz is extended up to 200 times of the wavelength of the RF signals, the measured distance is 5 times of the original measured distance. The presented proof-of-concept experiment demonstrates the feasibility of the system.« less

  3. Electrophysiological Evidence for the Sources of the Masking Level Difference

    ERIC Educational Resources Information Center

    Fowler, Cynthia G.

    2017-01-01

    Purpose: The purpose of this review article is to review evidence from auditory evoked potential studies to describe the contributions of the auditory brainstem and cortex to the generation of the masking level difference (MLD). Method: A literature review was performed, focusing on the auditory brainstem, middle, and late latency responses used…

  4. Near-Infrared Spectroscopic Measurements of Calf Muscle during Walking at Simulated Reduced Gravity - Preliminary Results

    NASA Technical Reports Server (NTRS)

    Ellerby, Gwenn E. C.; Lee, Stuart M. C.; Stroud, Leah; Norcross, Jason; Gernhardt, Michael; Soller, Babs R.

    2008-01-01

    Consideration for lunar and planetary exploration space suit design can be enhanced by investigating the physiologic responses of individual muscles during locomotion in reduced gravity. Near-infrared spectroscopy (NIRS) provides a non-invasive method to study the physiology of individual muscles in ambulatory subjects during reduced gravity simulations. PURPOSE: To investigate calf muscle oxygen saturation (SmO2) and pH during reduced gravity walking at varying treadmill inclines and added mass conditions using NIRS. METHODS: Four male subjects aged 42.3 +/- 1.7 years (mean +/- SE) and weighing 77.9 +/- 2.4 kg walked at a moderate speed (3.2 +/- 0.2 km/h) on a treadmill at inclines of 0, 10, 20, and 30%. Unsuited subjects were attached to a partial gravity simulator which unloaded the subject to simulate body weight plus the additional weight of a space suit (121 kg) in lunar gravity (0.17G). Masses of 0, 11, 23, and 34 kg were added to the subject and then unloaded to maintain constant weight. Spectra were collected from the lateral gastrocnemius (LG), and SmO2 and pH were calculated using previously published methods (Yang et al. 2007 Optics Express ; Soller et al. 2008 J Appl Physiol). The effects of incline and added mass on SmO2 and pH were analyzed through repeated measures ANOVA. RESULTS: SmO2 and pH were both unchanged by added mass (p>0.05), so data from trials at the same incline were averaged. LG SmO2 decreased significantly with increasing incline (p=0.003) from 61.1 +/- 2.0% at 0% incline to 48.7 +/- 2.6% at 30% incline, while pH was unchanged by incline (p=0.12). CONCLUSION: Increasing the incline (and thus work performed) during walking causes the LG to extract more oxygen from the blood supply, presumably to support the increased metabolic cost of uphill walking. The lack of an effect of incline on pH may indicate that, while the intensity of exercise has increased, the LG has not reached a level of work above the anaerobic threshold. In these preliminary studies, 30% incline walking at reduced gravity may not require anaerobic LG activity due to the low exercise intensity (42.8 +/- 1.6% of VO(sub 2max)). It is also possible that at reduced gravity additional work is being done by muscle groups other than the calf.

  5. A large format membrane-based x-ray mask for microfluidic chip fabrication

    NASA Astrophysics Data System (ADS)

    Wang, Lin; Zhang, Min; Desta, Yohannes; Melzak, J.; Wu, C. H.; Peng, Zhengchun

    2006-02-01

    X-ray lithography is a very good option for the fabrication of micro-devices especially when high aspect ratio patterns are required. Membrane-based x-ray masks are commonly used for high-resolution x-ray lithography. A thin layer of silicon nitride (Si3N4) or silicon carbide (SiC) film (1-2 µm) is normally used as the membrane material for x-ray mask fabrication (Wells G M, Reilly M, Nachman R, Cerrina F, El-Khakani M A and Chaker M 1993 Mater. Res. Soc. Conf. Proc. 306 81-9 Shoki T, Nagasawa H, Kosuga H, Yamaguchi Y, Annaka N, Amemiya I and Nagarekawa O 1993 SPIE Proc. 1924 450-6). The freestanding membrane window of an x-ray mask, which defines the exposing area of the x-ray mask, can be obtained by etching a pre-defined area on a silicon wafer from the backside (Wang L, Desta Y, Fettig R K, Goettert J, Hein H, Jakobs P and Chulz J 2004 J. Micromech. Microeng. 14 722-6). Usually, the window size of an x-ray mask is around 20 × 20 mm because of the low tensile stress of the membrane (10-100 MPa), and the larger window dimension of an x-ray mask may cause the deformation of membranes and lower the mask quality. However, x-ray masks with larger windows are preferred for micro-device fabrication in order to increase the productivity. We analyzed the factors which influence the flatness of large format x-ray masks and fabricated x-ray masks with a window size of 55 × 55 mm and 46 × 65 mm on 1 µm thick membranes by increasing the tensile stress of the membranes (>300 MPa) and optimizing the stress of the absorber layer. The large format x-ray mask was successfully applied for the fabrication of microfluidic chips.

  6. N-terminus determines activity and specificity of styrene monooxygenase reductases.

    PubMed

    Heine, Thomas; Scholtissek, Anika; Westphal, Adrie H; van Berkel, Willem J H; Tischler, Dirk

    2017-12-01

    Styrene monooxygenases (SMOs) are two-enzyme systems that catalyze the enantioselective epoxidation of styrene to (S)-styrene oxide. The FADH 2 co-substrate of the epoxidase component (StyA) is supplied by an NADH-dependent flavin reductase (StyB). The genome of Rhodococcus opacus 1CP encodes two SMO systems. One system, which we define as E1-type, displays homology to the SMO from Pseudomonas taiwanensis VLB120. The other system, originally reported as a fused system (RoStyA2B), is defined as E2-type. Here we found that E1-type RoStyB is inhibited by FMN, while RoStyA2B is known to be active with FMN. To rationalize the observed specificity of RoStyB for FAD, we generated an artificial reductase, designated as RoStyBart, in which the first 22 amino acid residues of RoStyB were joined to the reductase part of RoStyA2B, while the oxygenase part (A2) was removed. RoStyBart mainly purified as apo-protein and mimicked RoStyB in being inhibited by FMN. Pre-incubation with FAD yielded a turnover number at 30°C of 133.9±3.5s -1 , one of the highest rates observed for StyB reductases. RoStyBart holo-enzyme switches to a ping-pong mechanism and fluorescence analysis indicated for unproductive binding of FMN to the second (co-substrate) binding site. In summary, it is shown for the first time that optimization of the N-termini of StyB reductases allows the evolution of their activity and specificity. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Spatial Attention Enhances Perceptual Processing of Single-Element Displays

    NASA Technical Reports Server (NTRS)

    Bacon, William; Johnston, James C.; Remington, Roger W.; Null, Cynthia H. (Technical Monitor)

    1994-01-01

    Shiu and Pashler (1993) reported that precueing masked, single-element displays had negligible effects on identification accuracy. They argued that spatial attention does not actually enhance stimulus perceptibility, but only reduces decision noise. Alternatively, such negative results may arise if cues are sub-optimal, or if masks place an insufficient premium on timely deployment of attention. We report results showing that valid cueing enhances processing of even single-element displays. Spatial attention does indeed enhance perceptual processes.

  8. Identifying typical physical activity on smartphone with varying positions and orientations.

    PubMed

    Miao, Fen; He, Yi; Liu, Jinlei; Li, Ye; Ayoola, Idowu

    2015-04-13

    Traditional activity recognition solutions are not widely applicable due to a high cost and inconvenience to use with numerous sensors. This paper aims to automatically recognize physical activity with the help of the built-in sensors of the widespread smartphone without any limitation of firm attachment to the human body. By introducing a method to judge whether the phone is in a pocket, we investigated the data collected from six positions of seven subjects, chose five signals that are insensitive to orientation for activity classification. Decision trees (J48), Naive Bayes and Sequential minimal optimization (SMO) were employed to recognize five activities: static, walking, running, walking upstairs and walking downstairs. The experimental results based on 8,097 activity data demonstrated that the J48 classifier produced the best performance with an average recognition accuracy of 89.6% during the three classifiers, and thus would serve as the optimal online classifier. The utilization of the built-in sensors of the smartphone to recognize typical physical activities without any limitation of firm attachment is feasible.

  9. High-radiance LDP source for mask inspection and beam line applications (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Teramoto, Yusuke; Santos, Bárbara; Mertens, Guido; Kops, Ralf; Kops, Margarete; von Wezyk, Alexander; Bergmann, Klaus; Yabuta, Hironobu; Nagano, Akihisa; Ashizawa, Noritaka; Taniguchi, Yuta; Yamatani, Daiki; Shirai, Takahiro; Kasama, Kunihiko

    2017-04-01

    High-throughput actinic mask inspection tools are needed as EUVL begins to enter into volume production phase. One of the key technologies to realize such inspection tools is a high-radiance EUV source of which radiance is supposed to be as high as 100 W/mm2/sr. Ushio is developing laser-assisted discharge-produced plasma (LDP) sources. Ushio's LDP source is able to provide sufficient radiance as well as cleanliness, stability and reliability. Radiance behind the debris mitigation system was confirmed to be 120 W/mm2/sr at 9 kHz and peak radiance at the plasma was increased to over 200 W/mm2/sr in the recent development which supports high-throughput, high-precision mask inspection in the current and future technology nodes. One of the unique features of Ushio's LDP source is cleanliness. Cleanliness evaluation using both grazing-incidence Ru mirrors and normal-incidence Mo/Si mirrors showed no considerable damage to the mirrors other than smooth sputtering of the surface at the pace of a few nm per Gpulse. In order to prove the system reliability, several long-term tests were performed. Data recorded during the tests was analyzed to assess two-dimensional radiance stability. In addition, several operating parameters were monitored to figure out which contributes to the radiance stability. The latest model that features a large opening angle was recently developed so that the tool can utilize a large number of debris-free photons behind the debris shield. The model was designed both for beam line application and high-throughput mask inspection application. At the time of publication, the first product is supposed to be in use at the customer site.

  10. Statistical mechanics of image processing by digital halftoning

    NASA Astrophysics Data System (ADS)

    Inoue, Jun-Ichi; Norimatsu, Wataru; Saika, Yohei; Okada, Masato

    2009-03-01

    We consider the problem of digital halftoning (DH). The DH is an image processing representing each grayscale in images in terms of black and white dots, and it is achieved by making use of the threshold dither mask, namely, each pixel is determined as black if the grayscale pixel is greater than or equal to the mask value and as white vice versa. To determine the mask for a given grayscale image, we assume that human-eyes might recognize the BW dots as the corresponding grayscale by linear filters. Then, the Hamiltonian is constructed as a distance between the original and recognized images which is written in terms of the mask. Finding the ground state of the Hamiltonian via deterministic annealing, we obtain the optimal mask and the BW dots simultaneously. From the spectrum analysis, we find that the BW dots are desirable from the view point of human-eyes modulation properties. We also show that the lower bound of the mean square error for the inverse process of the DH is minimized on the Nishimori line which is well-known in the research field of spin glasses.

  11. Antigen Masking During Fixation and Embedding, Dissected

    PubMed Central

    Scalia, Carla Rossana; Boi, Giovanna; Bolognesi, Maddalena Maria; Riva, Lorella; Manzoni, Marco; DeSmedt, Linde; Bosisio, Francesca Maria; Ronchi, Susanna; Leone, Biagio Eugenio; Cattoretti, Giorgio

    2016-01-01

    Antigen masking in routinely processed tissue is a poorly understood process caused by multiple factors. We sought to dissect the effect on antigenicity of each step of processing by using frozen sections as proxies of the whole tissue. An equivalent extent of antigen masking occurs across variable fixation times at room temperature. Most antigens benefit from longer fixation times (>24 hr) for optimal detection after antigen retrieval (AR; for example, Ki-67, bcl-2, ER). The transfer to a graded alcohol series results in an enhanced staining effect, reproduced by treating the sections with detergents, possibly because of a better access of the polymeric immunohistochemical detection system to tissue structures. A second round of masking occurs upon entering the clearing agent, mostly at the paraffin embedding step. This may depend on the non-freezable water removal. AR fully reverses the masking due both to the fixation time and the paraffin embedding. AR itself destroys some epitopes which do not survive routine processing. Processed frozen sections are a tool to investigate fixation and processing requirements for antigens in routine specimens. PMID:27798289

  12. Coded aperture ptychography: uniqueness and reconstruction

    NASA Astrophysics Data System (ADS)

    Chen, Pengwen; Fannjiang, Albert

    2018-02-01

    Uniqueness of solution is proved for any ptychographic scheme with a random mask under a minimum overlap condition and local geometric convergence analysis is given for the alternating projection (AP) and Douglas-Rachford (DR) algorithms. DR is shown to possess a unique fixed point in the object domain and for AP a simple criterion for distinguishing the true solution among possibly many fixed points is given. A minimalist scheme, where the adjacent masks overlap 50% of the area and each pixel of the object is illuminated by exactly four illuminations, is conveniently parametrized by the number q of shifted masks in each direction. The lower bound 1  -  C/q 2 is proved for the geometric convergence rate of the minimalist scheme, predicting a poor performance with large q which is confirmed by numerical experiments. The twin-image ambiguity is shown to arise for certain Fresnel masks and degrade the performance of reconstruction. Extensive numerical experiments are performed to explore the general features of a well-performing mask, the optimal value of q and the robustness with respect to measurement noise.

  13. Photomask etch system and process for 10nm technology node and beyond

    NASA Astrophysics Data System (ADS)

    Chandrachood, Madhavi; Grimbergen, Michael; Yu, Keven; Leung, Toi; Tran, Jeffrey; Chen, Jeff; Bivens, Darin; Yalamanchili, Rao; Wistrom, Richard; Faure, Tom; Bartlau, Peter; Crawford, Shaun; Sakamoto, Yoshifumi

    2015-10-01

    While the industry is making progress to offer EUV lithography schemes to attain ultimate critical dimensions down to 20 nm half pitch, an interim optical lithography solution to address an immediate need for resolution is offered by various integration schemes using advanced PSM (Phase Shift Mask) materials including thin e-beam resist and hard mask. Using the 193nm wavelength to produce 10nm or 7nm patterns requires a range of optimization techniques, including immersion and multiple patterning, which place a heavy demand on photomask technologies. Mask schemes with hard mask certainly help attain better selectivity and hence better resolution but pose integration challenges and defectivity issues. This paper presents a new photomask etch solution for attenuated phase shift masks that offers high selectivity (Cr:Resist > 1.5:1), tighter control on the CD uniformity with a 3sigma value approaching 1 nm and controllable CD bias (5-20 nm) with excellent CD linearity performance (<5 nm) down to the finer resolution. The new system has successfully demonstrated capability to meet the 10 nm node photomask CD requirements without the use of more complicated hard mask phase shift blanks. Significant improvement in post wet clean recovery performance was demonstrated by the use of advanced chamber materials. Examples of CD uniformity, linearity, and minimum feature size, and etch bias performance on 10 nm test site and production mask designs will be shown.

  14. Full-chip level MEEF analysis using model based lithography verification

    NASA Astrophysics Data System (ADS)

    Kim, Juhwan; Wang, Lantian; Zhang, Daniel; Tang, Zongwu

    2005-11-01

    MEEF (Mask Error Enhancement Factor) has become a critical factor in CD uniformity control since optical lithography process moved to sub-resolution era. A lot of studies have been done by quantifying the impact of the mask CD (Critical Dimension) errors on the wafer CD errors1-2. However, the benefits from those studies were restricted only to small pattern areas of the full-chip data due to long simulation time. As fast turn around time can be achieved for the complicated verifications on very large data by linearly scalable distributed processing technology, model-based lithography verification becomes feasible for various types of applications such as post mask synthesis data sign off for mask tape out in production and lithography process development with full-chip data3,4,5. In this study, we introduced two useful methodologies for the full-chip level verification of mask error impact on wafer lithography patterning process. One methodology is to check MEEF distribution in addition to CD distribution through process window, which can be used for RET/OPC optimization at R&D stage. The other is to check mask error sensitivity on potential pinch and bridge hotspots through lithography process variation, where the outputs can be passed on to Mask CD metrology to add CD measurements on those hotspot locations. Two different OPC data were compared using the two methodologies in this study.

  15. An optimized OPC and MDP flow for reducing mask write time and mask cost

    NASA Astrophysics Data System (ADS)

    Yang, Ellyn; Li, Cheng He; Park, Se Jin; Zhu, Yu; Guo, Eric

    2010-09-01

    In the process of optical proximity correction, layout edge or fragment is migrating to proper position in order to minimize edge placement error (EPE). During this fragment migration, several factors other than EPE can be also taken into account as a part of cost function for optimal fragment displacement. Several factors are devised in favor of OPC stability, which can accommodate room for high mask error enhancement factor (MEEF), lack of process window, catastrophic pattern failure such as pinch/bridge and improper fragmentation. As technology node becomes finer, there happens conflict between OPC accuracy and stability. Especially for metal layers, OPC has focused on the stability by loss of accurate OPC results. On this purpose, several techniques have been introduced, which are target smoothing, process window aware OPC, model-based retargeting and adaptive OPC. By utilizing those techniques, OPC enables more stabilized patterning, instead of realizing design target exactly on wafer. Inevitably, post-OPC layouts become more complicated because those techniques invoke additional edge, or fragments prior to correction or during OPC iteration. As a result, jogs of post OPC layer can be dramatically increased, which results in huge number of shot count after data fracturing. In other words, there is trade-off relationship between data complexity and various methods for OPC stability. In this paper, those relationships have been investigated with respect to several technology nodes. The mask shot count reduction is achieved by reducing the number of jogs with which EPE difference are within pre-specified value. The effect of jog smoothing on OPC output - in view of OPC performance and mask data preparation - was studied quantitatively for respective technology nodes.

  16. Masked Phonological Priming Effects in English: Are They Real? Do They Matter?

    ERIC Educational Resources Information Center

    Rastle, Kathleen; Brysbaert, Marc

    2006-01-01

    For over 15 years, masked phonological priming effects have been offered as evidence that phonology plays a leading role in visual word recognition. The existence of these effects--along with their theoretical implications--has, however, been disputed. The authors present three sources of evidence relevant to an assessment of the existence and…

  17. Production of EUV mask blanks with low killer defects

    NASA Astrophysics Data System (ADS)

    Antohe, Alin O.; Kearney, Patrick; Godwin, Milton; He, Long; John Kadaksham, Arun; Goodwin, Frank; Weaver, Al; Hayes, Alan; Trigg, Steve

    2014-04-01

    For full commercialization, extreme ultraviolet lithography (EUVL) technology requires the availability of EUV mask blanks that are free of defects. This remains one of the main impediments to the implementation of EUV at the 22 nm node and beyond. Consensus is building that a few small defects can be mitigated during mask patterning, but defects over 100 nm (SiO2 equivalent) in size are considered potential "killer" defects or defects large enough that the mask blank would not be usable. The current defect performance of the ion beam sputter deposition (IBD) tool will be discussed and the progress achieved to date in the reduction of large size defects will be summarized, including a description of the main sources of defects and their composition.

  18. Development of a 0.1 μm linewidth fabrication process for x-ray lithography with a laser plasma source

    NASA Astrophysics Data System (ADS)

    Bobkowski, Romuald; Fedosejevs, Robert; Broughton, James N.

    1999-06-01

    A process has been developed for the purpose of fabricating 0.1 micron linewidth interdigital electrode patterns based on proximity x-ray lithography using a laser-plasma source. Such patterns are required in the manufacture of surface acoustic wave devices. The x-ray lithography was carried out using emission form a Cu plasma produced by a 15Hz, 248nm KrF excimer laser. A temporally multiplexed 50ps duration seed pulse was used to extract the KrF laser energy producing a train of several 50ps pulses spaced approximately 2ns apart within each output pulse. Each short pulse within the train gave the high focal spot intensity required to achieve high efficiency emission of keV x-rays. The first stage of the overall process involves the fabrication of x-ray mask patterns on 1 micron thick Si3N4 membranes using 3-beam lithography followed by gold electroplating. The second stage involves x-ray exposure of a chemically amplified resist through the mask patterns to produce interdigital electrode patterns with 0.1 micron linewidth. Helium background gas and thin polycarbonate/aluminum filters are employed to prevent debris particles from the laser-plasma source form reaching the exposed sample. A computer control system fires the laser and monitors the x-ray flux from the laser-plasma source to insure the desired x-ray exposure is achieved at the resist. In order to reduce diffusion effects in the chemically amplified resist during the post exposure bake the temperature had to be reduced from that normally used. Good reproduction of 0.1 micron linewidth patterns into the x-ray resist was obtained once the exposure parameters and post exposure bake were optimized. A compact exposure station using flowing helium at atmospheric pressure has also been developed for the process, alleviating the need for a vacuum chamber. The details of the overall process and the compact exposure station will be presented.

  19. VizieR Online Data Catalog: Radial velocities in A1914 (Barrena+, 2013)

    NASA Astrophysics Data System (ADS)

    Barrena, R.; Girardi, M.; Boschin, W.

    2014-04-01

    We performed observations of A1914 using Device Optimized for the Low Resolution (DOLORES) multi-object spectrograph at the TNG telescope in 2010 March. We used the LR-B grism, which provides a dispersion of 187Å/mm. DOLORES works with a 2048x2048 pixels E2V CCD. The pixel size is 13.5um. We retrieved a total of four multi-object spectroscopy (MOS) masks containing 146 slits. We exposed 3600s for each mask. (1 data file).

  20. VizieR Online Data Catalog: Velocities in ZwCl2341.1+0000 field (Boschin+, 2013)

    NASA Astrophysics Data System (ADS)

    Boschin, W.; Girardi, M.; Barrena, R.

    2014-07-01

    Multi-object spectroscopic observations of ZwCl 2341+00 were carried out at the TNG in 2009 October, 2011 August and 2011 December. We used the instrument Device Optimized for the Low Resolution (DOLORES) in multi-object spectroscopy (MOS) mode with the LR-B Grism. In summary, we observed four MOS masks for a total of 142 slits. The total exposure time was 3600s for three masks and 5400s for the last one. (1 data file).

  1. Tradeoff between insensitivity to depth-induced spherical aberration and resolution of 3D fluorescence imaging due to the use of wavefront encoding with a radially symmetric phase mask

    NASA Astrophysics Data System (ADS)

    Doblas, Ana; Dutta, Ananya; Saavedra, Genaro; Preza, Chrysanthe

    2018-02-01

    Previously, a wavefront encoded (WFE) imaging system implemented using a squared cubic (SQUBIC) phase mask has been verified to reduce the sensitivity of the imaging system to spherical aberration (SA). The strength of the SQUBIC phase mask and, as consequence, the performance of the WFE system are controlled by a design parameter, A. Although the higher the A-value, the more tolerant the WFE system is to SA, this is accomplished at the expense of the effective imaging resolution. In this contribution, we investigate this tradeoff in order to find an optimal A-value to balance the effect of SA and loss of resolution.

  2. Study of shape evaluation for mask and silicon using large field of view

    NASA Astrophysics Data System (ADS)

    Matsuoka, Ryoichi; Mito, Hiroaki; Shinoda, Shinichi; Toyoda, Yasutaka

    2010-09-01

    We have developed a highly integrated method of mask and silicon metrology. The aim of this integration is evaluating the performance of the silicon corresponding to Hotspot on a mask. It can use the mask shape of a large field, besides. The method adopts a metrology management system based on DBM (Design Based Metrology). This is the high accurate contouring created by an edge detection algorithm used in mask CD-SEM and silicon CD-SEM. Currently, as semiconductor manufacture moves towards even smaller feature size, this necessitates more aggressive optical proximity correction (OPC) to drive the super-resolution technology (RET). In other words, there is a trade-off between highly precise RET and mask manufacture, and this has a big impact on the semiconductor market that centers on the mask business. As an optimal solution to these issues, we provide a DFM solution that extracts 2-dimensional data for a more realistic and error-free simulation by reproducing accurately the contour of the actual mask, in addition to the simulation results from the mask data. On the other hand, there is roughness in the silicon form made from a mass-production line. Moreover, there is variation in the silicon form. For this reason, quantification of silicon form is important, in order to estimate the performance of a pattern. In order to quantify, the same form is equalized in two dimensions. And the method of evaluating based on the form is popular. In this study, we conducted experiments for averaging method of the pattern (Measurement Based Contouring) as two-dimensional mask and silicon evaluation technique. That is, observation of the identical position of a mask and a silicon was considered. The result proved its detection accuracy and reliability of variability on two-dimensional pattern (mask and silicon) and is adaptable to following fields of mask quality management. •Discrimination of nuisance defects for fine pattern. •Determination of two-dimensional variability of pattern. •Verification of the performance of the pattern of various kinds of Hotspots. In this report, we introduce the experimental results and the application. We expect that the mask measurement and the shape control on mask production will make a huge contribution to mask yield-enhancement and that the DFM solution for mask quality control process will become much more important technology than ever. It is very important to observe the form of the same location of Design, Mask, and Silicon in such a viewpoint. And we report it about algorithm of the image composition in Large Field.

  3. DfM requirements and ROI analysis for system-on-chip

    NASA Astrophysics Data System (ADS)

    Balasinski, Artur

    2005-11-01

    DfM (Design-for-Manufacturability) has become staple requirement beyond 100 nm technology node for efficient generation of mask data, cost reduction, and optimal circuit performance. Layout pattern has to comply to many requirements pertaining to database structure and complexity, suitability for image enhancement by the optical proximity correction, and mask data pattern density and distribution over the image field. These requirements are of particular complexity for Systems-on-Chip (SoC). A number of macro-, meso-, and microscopic effects such as reticle macroloading, planarization dishing, and pattern bridging or breaking would compromise fab yield, device performance, or both. In order to determine the optimal set of DfM rules applicable to the particular designs, Return-on-Investment and Failure Mode and Effect Analysis (FMEA) are proposed.

  4. Small Indian mongooses and masked palm civets serve as new reservoirs of Bartonella henselae and potential sources of infection for humans.

    PubMed

    Sato, S; Kabeya, H; Shigematsu, Y; Sentsui, H; Une, Y; Minami, M; Murata, K; Ogura, G; Maruyama, S

    2013-12-01

    The prevalence and genetic properties of Bartonella species were investigated in small Indian mongooses and masked palm civets in Japan. Bartonella henselae, the causative agent of cat-scratch disease (CSD) was isolated from 15.9% (10/63) of the mongooses and 2.0% (1/50) of the masked palm civets, respectively. The bacteraemic level ranged from 3.0 × 10(1) to 8.9 × 10(3) CFU/mL in mongooses and was 7.0 × 10(3) CFU/mL in the masked palm civet. Multispacer typing (MST) analysis based on nine intergenic spacers resulted in the detection of five MST genotypes (MSTs 8, 14, 37, 58 and 59) for the isolates, which grouped in lineage 1 with MST genotypes of isolates from all CSD patients and most of the cats in Japan. It was also found that MST14 from the mongoose strains was the predominant genotype of cat and human strains. This is the first report on the isolation of B. henselae from small Indian mongooses and masked palm civets. The data obtained in the present study suggest that these animals serve as new reservoirs for B. henselae, and may play a role as potential sources of human infection. © 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.

  5. An automatic iris occlusion estimation method based on high-dimensional density estimation.

    PubMed

    Li, Yung-Hui; Savvides, Marios

    2013-04-01

    Iris masks play an important role in iris recognition. They indicate which part of the iris texture map is useful and which part is occluded or contaminated by noisy image artifacts such as eyelashes, eyelids, eyeglasses frames, and specular reflections. The accuracy of the iris mask is extremely important. The performance of the iris recognition system will decrease dramatically when the iris mask is inaccurate, even when the best recognition algorithm is used. Traditionally, people used the rule-based algorithms to estimate iris masks from iris images. However, the accuracy of the iris masks generated this way is questionable. In this work, we propose to use Figueiredo and Jain's Gaussian Mixture Models (FJ-GMMs) to model the underlying probabilistic distributions of both valid and invalid regions on iris images. We also explored possible features and found that Gabor Filter Bank (GFB) provides the most discriminative information for our goal. Finally, we applied Simulated Annealing (SA) technique to optimize the parameters of GFB in order to achieve the best recognition rate. Experimental results show that the masks generated by the proposed algorithm increase the iris recognition rate on both ICE2 and UBIRIS dataset, verifying the effectiveness and importance of our proposed method for iris occlusion estimation.

  6. Passive monitoring for near surface void detection using traffic as a seismic source

    NASA Astrophysics Data System (ADS)

    Zhao, Y.; Kuzma, H. A.; Rector, J.; Nazari, S.

    2009-12-01

    In this poster we present preliminary results based on our several field experiments in which we study seismic detection of voids using a passive array of surface geophones. The source of seismic excitation is vehicle traffic on nearby roads, which we model as a continuous line source of seismic energy. Our passive seismic technique is based on cross-correlation of surface wave fields and studying the resulting power spectra, looking for "shadows" caused by the scattering effect of a void. High frequency noise masks this effect in the time domain, so it is difficult to see on conventional traces. Our technique does not rely on phase distortions caused by small voids because they are generally too tiny to measure. Unlike traditional impulsive seismic sources which generate highly coherent broadband signals, perfect for resolving phase but too weak for resolving amplitude, vehicle traffic affords a high power signal a frequency range which is optimal for finding shallow structures. Our technique results in clear detections of an abandoned railroad tunnel and a septic tank. The ultimate goal of this project is to develop a technology for the simultaneous imaging of shallow underground structures and traffic monitoring near these structures.

  7. Status of EUVL mask development in Europe (Invited Paper)

    NASA Astrophysics Data System (ADS)

    Peters, Jan H.

    2005-06-01

    EUV lithography is the prime candidate for the next generation lithography technology after 193 nm immersion lithography. The commercial onset for this technology is expected for the 45 nm half-pitch technology or below. Several European and national projects and quite a large number of companies and research institutions in Europe work on various aspects of the technological challenges to make EUV a commercially viable technology in the not so far future. Here the development of EUV sources, the development of an EUV exposure tools, metrology tools dedicated for characterization of mask, the production of EUV mask blanks and the mask structuring itself are the key areas in which major activities can be found. In this talk we will primarily focus on those activities, which are related to establish an EUV mask supply chain with all its ingredients from substrate production, polishing, deposition of EUV layers, blank characterization, mask patterning process and the consecutive metrology and defect inspection as well as shipping and handling from blank supply to usage in the wafer fab. The EUV mask related projects on the national level are primarily supported by the French Ministry of Economics and Finance (MinEFi) and the German Ministry of Education and Research (BMBF).

  8. A randomised controlled trial on the effect of mask choice on residual respiratory events with continuous positive airway pressure treatment.

    PubMed

    Ebben, Matthew R; Narizhnaya, Mariya; Segal, Alan Z; Barone, Daniel; Krieger, Ana C

    2014-06-01

    It has been found that mask style can affect the amount of continuous positive airway pressure (CPAP) required to reduce an apnoea/hyponoea index (AHI) to < 5/h on a titration study. However, it was not previously known whether switching from one CPAP mask style to another post titration could affect the residual AHI with CPAP. The purpose of this study was to investigate the differences in residual AHI with CPAP treatment between oronasal and nasal masks. Twenty-one subjects (age mean (M)=62.9, body mass index (BMI) M=29.6 kg/m2) were randomised (14 subjects completed the protocol) to undergo an in-laboratory CPAP titration with either a nasal mask or an oronasal mask. Subjects were then assigned this mask for 3weeks of at-home CPAP use with the optimal treatment pressure determined on the laboratory study (CPAP M=8.4 cm of H2O). At the end of this 3-week period, data were collected from the CPAP machine and the subject was given the other mask to use with the same CPAP settings for the next 3weeks at home (if the nasal mask was given initially, the oronasal one was given later and vice versa). On completion of the second 3-week period, data on residual AHI were again collected and compared with the first 3-week period on CPAP. A Wilcoxon Signed-Rank Test (two-tailed) revealed that residual AHI with CPAP treatment was significantly higher with the oronasal compared with the nasal mask (z = -3.296, p<0.001). All 14 subjects had a higher residual AHI with the oronasal versus nasal mask, and 50% of the subjects had a residual AHI >10/h in the oronasal mask condition, even though all of these subjects were titrated to an AHI of < 5/h in the laboratory. A higher residual AHI was seen in all patients with the use of an oronasal mask compared with a nasal mask. Switching to an oronasal mask post titration results in an increase in residual AHI with CPAP treatment, and pressure adjustment may be warranted. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Severe maternal morbidity and near miss due to postpartum hemorrhage in a national multicenter surveillance study.

    PubMed

    Rocha Filho, Edilberto A; Costa, Maria L; Cecatti, Jose G; Parpinelli, Mary A; Haddad, Samira M; Pacagnella, Rodolfo C; Sousa, Maria H; Melo, Elias F; Surita, Fernanda G; Souza, Joao P

    2015-02-01

    To assess the occurrence of severe maternal complications owing to postpartum hemorrhage (PPH) and its associated factors. A secondary analysis of data from a multicenter cross-sectional prospective surveillance study included 9555 cases of severe maternal morbidity at 27 centers in Brazil between July 2009 and June 2010. Complications of PPH, conditions of severity management, and sociodemographic and obstetric characteristics were assessed. Factors independently associated with severe maternal outcome (SMO) were identified using multiple regression analysis. Overall, 1192 (12.5%) of the 9555 women experienced complications owing to PPH (981 had potentially life-threatening conditions, 181 maternal near miss, and 30 had died). The SMO ratio was 2.6 per 1000 live births among women with PPH and 8.5 per 1000 live births among women with other complications. Women with PPH had a higher risk of blood transfusion and return to the operating theater than did those with complications from other causes. Maternal age, length of pregnancy, previous uterine scar, and cesarean delivery were the main factors associated with an increased risk of SMO secondary to PPH. PPH frequently leads to severe maternal morbidity. A surveillance system can identify the main causes of morbidity and could help to improve care, especially among women identified as being at high risk of PPH. Copyright © 2014 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  10. Rescue therapy by switching to total face mask after failure of face mask-delivered noninvasive ventilation in do-not-intubate patients in acute respiratory failure.

    PubMed

    Lemyze, Malcolm; Mallat, Jihad; Nigeon, Olivier; Barrailler, Stéphanie; Pepy, Florent; Gasan, Gaëlle; Vangrunderbeeck, Nicolas; Grosset, Philippe; Tronchon, Laurent; Thevenin, Didier

    2013-02-01

    To evaluate the impact of switching to total face mask in cases where face mask-delivered noninvasive mechanical ventilation has already failed in do-not-intubate patients in acute respiratory failure. Prospective observational study in an ICU and a respiratory stepdown unit over a 12-month study period. Switching to total face mask, which covers the entire face, when noninvasive mechanical ventilation using facial mask (oronasal mask) failed to reverse acute respiratory failure. Seventy-four patients with a do-not-intubate order and treated by noninvasive mechanical ventilation for acute respiratory failure. Failure of face mask-delivered noninvasive mechanical ventilation was associated with a three-fold increase in in-hospital mortality (36% vs. 10.5%; p = 0.009). Nevertheless, 23 out of 36 patients (64%) in whom face mask-delivered noninvasive mechanical ventilation failed to reverse acute respiratory failure and, therefore, switched to total face mask survived hospital discharge. Reasons for switching from facial mask to total face mask included refractory hypercapnic acute respiratory failure (n = 24, 66.7%), painful skin breakdown or facial mask intolerance (n = 11, 30%), and refractory hypoxemia (n = 1, 2.7%). In the 24 patients switched from facial mask to total face mask because of refractory hypercapnia, encephalopathy score (3 [3-4] vs. 2 [2-3]; p < 0.0001), PaCO2 (87 ± 25 mm Hg vs. 70 ± 17 mm Hg; p < 0.0001), and pH (7.24 ± 0.1 vs. 7.32 ± 0.09; p < 0.0001) significantly improved after 2 hrs of total face mask-delivered noninvasive ventilation. Patients switched early to total face mask (in the first 12 hrs) developed less pressure sores (n = 5, 24% vs. n = 13, 87%; p = 0.0002), despite greater length of noninvasive mechanical ventilation within the first 48 hrs (44 hrs vs. 34 hrs; p = 0.05) and less protective dressings (n = 2, 9.5% vs. n = 8, 53.3%; p = 0.007). The optimal cutoff value for face mask-delivered noninvasive mechanical ventilation duration in predicting facial pressure sores was 11 hrs (area under the receiver operating characteristic curve, 0.86 ± 0.04; 95% confidence interval 0.76-0.93; p < 0.0001; sensitivity, 84%; specificity, 71%). In patients in hypercapnic acute respiratory failure, for whom escalation to intubation is deemed inappropriate, switching to total face mask can be proposed as a last resort therapy when face mask-delivered noninvasive mechanical ventilation has already failed to reverse acute respiratory failure. This strategy is particularly adapted to provide prolonged periods of continuous noninvasive mechanical ventilation while preventing facial pressure sores.

  11. Coma measurement by use of an alternating phase-shifting mask mark with a specific phase width

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

    Qiu Zicheng; Wang Xiangzhao; Yuan Qiongyan

    2009-01-10

    The correlation between the coma sensitivity of the alternating phase-shifting mask (Alt-PSM) mark and the mark's structure is studied based on the Hopkins theory of partially coherent imaging and positive resist optical lithography (PROLITH) simulation. It is found that an optimized Alt-PSM mark with its phase width being two-thirds its pitch has a higher sensitivity to coma than Alt-PSM marks with the same pitch and the different phase widths. The pitch of the Alt-PSM mark is also optimized by PROLITH simulation, and the structure of p=1.92{lambda}/NA and pw=2p/3 proves to be with the highest sensitivity. The optimized Alt-PSM mark ismore » used as a measurement mark to retrieve coma aberration from the projection optics in lithographic tools. In comparison with an ordinary Alt-PSM mark with its phase width being a half its pitch, the measurement accuracies of Z7 and Z14 apparently increase.« less

  12. NASA Tech Briefs, July 2007

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Topics covered include: Miniature Intelligent Sensor Module; "Smart" Sensor Module; Portable Apparatus for Electrochemical Sensing of Ethylene; Increasing Linear Dynamic Range of a CMOS Image Sensor; Flight Qualified Micro Sun Sensor; Norbornene-Based Polymer Electrolytes for Lithium Cells; Making Single-Source Precursors of Ternary Semiconductors; Water-Free Proton-Conducting Membranes for Fuel Cells; Mo/Ti Diffusion Bonding for Making Thermoelectric Devices; Photodetectors on Coronagraph Mask for Pointing Control; High-Energy-Density, Low-Temperature Li/CFx Primary Cells; G4-FETs as Universal and Programmable Logic Gates; Fabrication of Buried Nanochannels From Nanowire Patterns; Diamond Smoothing Tools; Infrared Imaging System for Studying Brain Function; Rarefying Spectra of Whispering-Gallery-Mode Resonators; Large-Area Permanent-Magnet ECR Plasma Source; Slot-Antenna/Permanent-Magnet Device for Generating Plasma; Fiber-Optic Strain Gauge With High Resolution And Update Rate; Broadband Achromatic Telecentric Lens; Temperature-Corrected Model of Turbulence in Hot Jet Flows; Enhanced Elliptic Grid Generation; Automated Knowledge Discovery From Simulators; Electro-Optical Modulator Bias Control Using Bipolar Pulses; Generative Representations for Automated Design of Robots; Mars-Approach Navigation Using In Situ Orbiters; Efficient Optimization of Low-Thrust Spacecraft Trajectories; Cylindrical Asymmetrical Capacitors for Use in Outer Space; Protecting Against Faults in JPL Spacecraft; Algorithm Optimally Allocates Actuation of a Spacecraft; and Radar Interferometer for Topographic Mapping of Glaciers and Ice Sheets.

  13. Robust resolution enhancement optimization methods to process variations based on vector imaging model

    NASA Astrophysics Data System (ADS)

    Ma, Xu; Li, Yanqiu; Guo, Xuejia; Dong, Lisong

    2012-03-01

    Optical proximity correction (OPC) and phase shifting mask (PSM) are the most widely used resolution enhancement techniques (RET) in the semiconductor industry. Recently, a set of OPC and PSM optimization algorithms have been developed to solve for the inverse lithography problem, which are only designed for the nominal imaging parameters without giving sufficient attention to the process variations due to the aberrations, defocus and dose variation. However, the effects of process variations existing in the practical optical lithography systems become more pronounced as the critical dimension (CD) continuously shrinks. On the other hand, the lithography systems with larger NA (NA>0.6) are now extensively used, rendering the scalar imaging models inadequate to describe the vector nature of the electromagnetic field in the current optical lithography systems. In order to tackle the above problems, this paper focuses on developing robust gradient-based OPC and PSM optimization algorithms to the process variations under a vector imaging model. To achieve this goal, an integrative and analytic vector imaging model is applied to formulate the optimization problem, where the effects of process variations are explicitly incorporated in the optimization framework. The steepest descent algorithm is used to optimize the mask iteratively. In order to improve the efficiency of the proposed algorithms, a set of algorithm acceleration techniques (AAT) are exploited during the optimization procedure.

  14. Body temperature variability (Part 2): masking influences of body temperature variability and a review of body temperature variability in disease.

    PubMed

    Kelly, Gregory S

    2007-03-01

    This is the second of a two-part review on body temperature variability. Part 1 discussed historical and modern findings on average body temperatures. It also discussed endogenous sources of temperature variability, including variations caused by site of measurement; circadian, menstrual, and annual biological rhythms; fitness; and aging. Part 2 reviews the effects of exogenous masking agents - external factors in the environment, diet, or lifestyle that can be a significant source of body temperature variability. Body temperature variability findings in disease states are also reviewed.

  15. Procedures for dealing with certain types of noise and systematic errors common to many Hadamard transform optical systems

    NASA Technical Reports Server (NTRS)

    Harwit, M.

    1977-01-01

    Sources of noise and error correcting procedures characteristic of Hadamard transform optical systems were investigated. Reduction of spectral noise due to noise spikes in the data, the effect of random errors, the relative performance of Fourier and Hadamard transform spectrometers operated under identical detector-noise-limited conditions, and systematic means for dealing with mask defects are among the topics discussed. The distortion in Hadamard transform optical instruments caused by moving Masks, incorrect mask alignment, missing measurements, and diffraction is analyzed and techniques for reducing or eliminating this distortion are described.

  16. Detection and Localization of Money Bills Concealed Behind Wooden Walls Using Compton Scattering

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

    Wart, Jason A. van; Hussein, Esam M.A.; Waller, Edward J

    2005-05-15

    This work presents a portable device for detecting visually obscured contraband money bills that may be hidden within conventional household walls for the purpose of avoiding confiscation. The device utilizes the Compton backscattering of photons emitted from a collimated {sup 241}Am source. The scattered photons are detected with a thin NaI(Tl) detector, either over a wide field of view for surface scanning of the wall or within a confined view field for depth scanning. The design of the device was optimized for best density contrast and highest count rate for a given source activity. It was shown that the minimummore » detectable amount of contraband, with >95% confidence level, is 86 paper bills. The contraband was detectable when hidden in household walls made of gyprock or wooden paneling, even when masked by higher density materials such as metallic piping. The device's capability exceeded those of commercially available density-based portable contraband detectors.« less

  17. Mask-to-wafer alignment system

    DOEpatents

    Sweatt, William C.; Tichenor, Daniel A.; Haney, Steven J.

    2003-11-04

    A modified beam splitter that has a hole pattern that is symmetric in one axis and anti-symmetric in the other can be employed in a mask-to-wafer alignment device. The device is particularly suited for rough alignment using visible light. The modified beam splitter transmits and reflects light from a source of electromagnetic radiation and it includes a substrate that has a first surface facing the source of electromagnetic radiation and second surface that is reflective of said electromagnetic radiation. The substrate defines a hole pattern about a central line of the substrate. In operation, an input beam from a camera is directed toward the modified beam splitter and the light from the camera that passes through the holes illuminates the reticle on the wafer. The light beam from the camera also projects an image of a corresponding reticle pattern that is formed on the mask surface of the that is positioned downstream from the camera. Alignment can be accomplished by detecting the radiation that is reflected from the second surface of the modified beam splitter since the reflected radiation contains both the image of the pattern from the mask and a corresponding pattern on the wafer.

  18. A novel and discriminative method of in vitro disintegration time for preparation and optimization of taste-masked orally disintegrating tablets of carbinoxamine maleate.

    PubMed

    Liu, Yali; Li, Peng; Qian, Rong; Sun, Tianyu; Fang, Fangzhi; Wang, Zonghua; Ke, Xue; Xu, Bohui

    2018-08-01

    The primary objective of this study was to mask bitter taste and decrease the disintegration time of carbinoxamine maleate (CAM) orally disintegrating tablets (ODTs). In order to screen the prescription of ODTs, a novel modified in vitro disintegration method (MIVDM) was developed to measure the in vitro disintegration time. In this method, different concentrations of ethanol served as disintegration medium in order to delay the in vitro water absorption and disintegration process of tablets. The MIVDM demonstrated good in vitro and in vivo correlation and proved more precise and discriminative than other reported methods. In this research, ion exchange resins (IERs) were used to mask bitter taste for improving mouthfeel. The drug-resin ratio and reaction temperature were investigated to obtain the optimum carbinoxamine resin complexes (CRCs). The characterization of CRCs revealed an amorphous state. ODTs were prepared by direct compression. Superdisintegrants and diluents of ODTs were screened first. Further optimization was carried out by using Box-Behnken design. The effect of (X 1 ) mannitol/microcrystalline cellulose ratio, (X 2 ) the amount of low-substituted hydroxypropylcellulose and (X 3 ) the hardness was investigated for achieving the lowest (Y) in vitro disintegration time. Technological characterization, wetting time, water absorption ratio, and roughness degree were evaluated. The CRCs and ODTs proved successful taste-masking efficiency. The end product improved patients' compliance. The developed MIVDM was practical for commercial use.

  19. Apparatus and method for generating partially coherent illumination for photolithography

    DOEpatents

    Sweatt, William C.

    2001-01-01

    The present invention introduces a novel scatter plate into the optical path of source light used for illuminating a replicated object. The scatter plate has been designed to interrupt a focused, incoming light beam by introducing between about 8 to 24 diffraction zones blazed onto the surface of the scatter plate which intercept the light and redirect it to a like number of different positions in the condenser entrance pupil each of which is determined by the relative orientation and the spatial frequency of the diffraction grating in each of the several zones. Light falling onto the scatter plate, therefore, generates a plurality of unphased sources of illumination as seen by the back half of the optical system. The system comprises a high brightness source, such as a laser, creating light which is taken up by a beam forming optic which focuses the incoming light into a condenser which in turn, focuses light into a field lens creating Kohler illumination image of the source in a camera entrance pupil. The light passing through the field lens illuminates a mask which interrupts the source light as either a positive or negative image of the object to be replicated. Light passing by the mask is focused into the entrance pupil of the lithographic camera creating an image of the mask onto a receptive media.

  20. Complex Pupil Masks for Aberrated Imaging of Closely Spaced Objects

    NASA Astrophysics Data System (ADS)

    Reddy, A. N. K.; Sagar, D. K.; Khonina, S. N.

    2017-12-01

    Current approach demonstrates the suppression of optical side-lobes and the contraction of the main lobe in the composite image of two object points of the optical system under the influence of defocusing effect when an asymmetric phase edges are imposed over the apodized circular aperture. The resolution of two point sources having different intensity ratio is discussed in terms of the modified Sparrow criterion, functions of the degree of coherence of the illumination, the intensity difference and the degree of asymmetric phase masking. Here we have introduced and explored the effects of focus aberration (defect-of-focus) on the two-point resolution of the optical systems. Results on the aberrated composite image of closely spaced objects with amplitude mask and asymmetric phase masks forms a significant contribution in astronomical and microscopic observations.

  1. A Deep Ensemble Learning Method for Monaural Speech Separation.

    PubMed

    Zhang, Xiao-Lei; Wang, DeLiang

    2016-03-01

    Monaural speech separation is a fundamental problem in robust speech processing. Recently, deep neural network (DNN)-based speech separation methods, which predict either clean speech or an ideal time-frequency mask, have demonstrated remarkable performance improvement. However, a single DNN with a given window length does not leverage contextual information sufficiently, and the differences between the two optimization objectives are not well understood. In this paper, we propose a deep ensemble method, named multicontext networks, to address monaural speech separation. The first multicontext network averages the outputs of multiple DNNs whose inputs employ different window lengths. The second multicontext network is a stack of multiple DNNs. Each DNN in a module of the stack takes the concatenation of original acoustic features and expansion of the soft output of the lower module as its input, and predicts the ratio mask of the target speaker; the DNNs in the same module employ different contexts. We have conducted extensive experiments with three speech corpora. The results demonstrate the effectiveness of the proposed method. We have also compared the two optimization objectives systematically and found that predicting the ideal time-frequency mask is more efficient in utilizing clean training speech, while predicting clean speech is less sensitive to SNR variations.

  2. Bayesian cloud detection for MERIS, AATSR, and their combination

    NASA Astrophysics Data System (ADS)

    Hollstein, A.; Fischer, J.; Carbajal Henken, C.; Preusker, R.

    2014-11-01

    A broad range of different of Bayesian cloud detection schemes is applied to measurements from the Medium Resolution Imaging Spectrometer (MERIS), the Advanced Along-Track Scanning Radiometer (AATSR), and their combination. The cloud masks were designed to be numerically efficient and suited for the processing of large amounts of data. Results from the classical and naive approach to Bayesian cloud masking are discussed for MERIS and AATSR as well as for their combination. A sensitivity study on the resolution of multidimensional histograms, which were post-processed by Gaussian smoothing, shows how theoretically insufficient amounts of truth data can be used to set up accurate classical Bayesian cloud masks. Sets of exploited features from single and derived channels are numerically optimized and results for naive and classical Bayesian cloud masks are presented. The application of the Bayesian approach is discussed in terms of reproducing existing algorithms, enhancing existing algorithms, increasing the robustness of existing algorithms, and on setting up new classification schemes based on manually classified scenes.

  3. ArF halftone PSM cleaning process optimization for next-generation lithography

    NASA Astrophysics Data System (ADS)

    Son, Yong-Seok; Jeong, Seong-Ho; Kim, Jeong-Bae; Kim, Hong-Seok

    2000-07-01

    ArF lithography which is expected for the next generation optical lithography is adapted for 0.13 micrometers design-rule and beyond. ArF half-tone phase shift mask (HT PSM) will be applied as 1st generation of ArF lithography. Also ArF PSM cleaning demands by means of tighter controls related to phase angle, transmittance and contamination on the masks. Phase angle on ArF HT PSM should be controlled within at least +/- 3 degree and transmittance controlled within at least +/- 3 percent after cleaning process and pelliclization. In the cleaning process of HT PSM, requires not only the remove the particle on mask, but also control to half-tone material for metamorphosis. Contamination defects on the Qz of half tone type PSM is not easy to remove on the photomask surface. New technology and methods of cleaning will be developed in near future, but we try to get out for limit contamination on the mask, without variation of phase angle and transmittance after cleaning process.

  4. Controlling bridging and pinching with pixel-based mask for inverse lithography

    NASA Astrophysics Data System (ADS)

    Kobelkov, Sergey; Tritchkov, Alexander; Han, JiWan

    2016-03-01

    Inverse Lithography Technology (ILT) has become a viable computational lithography candidate in recent years as it can produce mask output that results in process latitude and CD control in the fab that is hard to match with conventional OPC/SRAF insertion approaches. An approach to solving the inverse lithography problem as a nonlinear, constrained minimization problem over a domain mask pixels was suggested in the paper by Y. Granik "Fast pixel-based mask optimization for inverse lithography" in 2006. The present paper extends this method to satisfy bridging and pinching constraints imposed on print contours. Namely, there are suggested objective functions expressing penalty for constraints violations, and their minimization with gradient descent methods is considered. This approach has been tested with an ILT-based Local Printability Enhancement (LPTM) tool in an automated flow to eliminate hotspots that can be present on the full chip after conventional SRAF placement/OPC and has been applied in 14nm, 10nm node production, single and multiple-patterning flows.

  5. Process optimization for particle removal on blank chrome mask plates in preparation for resist application

    NASA Astrophysics Data System (ADS)

    Osborne, Stephen; Smith, Eryn; Woster, Eric; Pelayo, Anthony

    2002-03-01

    As integrated circuits require smaller lines to provide the memory and processing capability for tomorrow's marketplace, the photomask industry is adopting higher contrast resists to improve photomask lithography. Photomask yield for several high-contrast resist recipes may be improved by coating masks at the mask shop. When coating at a mask shop, an effective method is available that uses coat/bake cluster tools to ensure blanks are clean prior to coating. Many high-contrast resists are available, and some are more susceptible to time-dependent performance factors than conventional resists. One of these factors is the time between coating and writing. Although future methods may reduce the impact of this factor, one current trend is to reduce this time by coating plates at the mask shop just prior to writing. Establishing an effective process to clean blanks prior to coating is necessary for product quality control and is a new task that is critical for maskmakers who previously purchased mask plates but have decided to begin coating them within their facility. This paper provides a strategy and method to be used within coat/bake cluster tools to remove particle contamination from mask blanks. The process uses excimer-UV ionizing radiation and ozone to remove organic contaminants, and then uses a wet process combined with megasonic agitation, surfactant, and spin forces. Megasonic agitation with surfactant lifts up particles, while the convective outflow of water enhances centripetal shear without accumulating harmful charge.

  6. Vector scattering analysis of TPF coronagraph pupil masks

    NASA Astrophysics Data System (ADS)

    Ceperley, Daniel P.; Neureuther, Andrew R.; Lieber, Michael D.; Kasdin, N. Jeremy; Shih, Ta-Ming

    2004-10-01

    Rigorous finite-difference time-domain electromagnetic simulation is used to simulate the scattering from proto-typical pupil mask cross-section geometries and to quantify the differences from the normally assumed ideal on-off behavior. Shaped pupil plane masks are a promising technology for the TPF coronagraph mission. However the stringent requirements placed on the optics require that the detailed behavior of the edge-effects of these masks be examined carefully. End-to-end optical system simulation is essential and an important aspect is the polarization and cross-section dependent edge-effects which are the subject of this paper. Pupil plane masks are similar in many respects to photomasks used in the integrated circuit industry. Simulation capabilities such as the FDTD simulator, TEMPEST, developed for analyzing polarization and intensity imbalance effects in nonplanar phase-shifting photomasks, offer a leg-up in analyzing coronagraph masks. However, the accuracy in magnitude and phase required for modeling a chronograph system is extremely demanding and previously inconsequential errors may be of the same order of magnitude as the physical phenomena under study. In this paper, effects of thick masks, finite conductivity metals, and various cross-section geometries on the transmission of pupil-plane masks are illustrated. Undercutting the edge shape of Cr masks improves the effective opening width to within λ/5 of the actual opening but TE and TM polarizations require opposite compensations. The deviation from ideal is examined at the reference plane of the mask opening. Numerical errors in TEMPEST, such as numerical dispersion, perfectly matched layer reflections, and source haze are also discussed along with techniques for mitigating their impacts.

  7. New method of contour-based mask-shape compiler

    NASA Astrophysics Data System (ADS)

    Matsuoka, Ryoichi; Sugiyama, Akiyuki; Onizawa, Akira; Sato, Hidetoshi; Toyoda, Yasutaka

    2007-10-01

    We have developed a new method of accurately profiling a mask shape by utilizing a Mask CD-SEM. The method is intended to realize high accuracy, stability and reproducibility of the Mask CD-SEM adopting an edge detection algorithm as the key technology used in CD-SEM for high accuracy CD measurement. In comparison with a conventional image processing method for contour profiling, it is possible to create the profiles with much higher accuracy which is comparable with CD-SEM for semiconductor device CD measurement. In this report, we will introduce the algorithm in general, the experimental results and the application in practice. As shrinkage of design rule for semiconductor device has further advanced, an aggressive OPC (Optical Proximity Correction) is indispensable in RET (Resolution Enhancement Technology). From the view point of DFM (Design for Manufacturability), a dramatic increase of data processing cost for advanced MDP (Mask Data Preparation) for instance and surge of mask making cost have become a big concern to the device manufacturers. In a sense, it is a trade-off between the high accuracy RET and the mask production cost, while it gives a significant impact on the semiconductor market centered around the mask business. To cope with the problem, we propose the best method for a DFM solution in which two dimensional data are extracted for an error free practical simulation by precise reproduction of a real mask shape in addition to the mask data simulation. The flow centering around the design data is fully automated and provides an environment where optimization and verification for fully automated model calibration with much less error is available. It also allows complete consolidation of input and output functions with an EDA system by constructing a design data oriented system structure. This method therefore is regarded as a strategic DFM approach in the semiconductor metrology.

  8. Dynamics of normalization underlying masking in human visual cortex.

    PubMed

    Tsai, Jeffrey J; Wade, Alex R; Norcia, Anthony M

    2012-02-22

    Stimulus visibility can be reduced by other stimuli that overlap the same region of visual space, a process known as masking. Here we studied the neural mechanisms of masking in humans using source-imaged steady state visual evoked potentials and frequency-domain analysis over a wide range of relative stimulus strengths of test and mask stimuli. Test and mask stimuli were tagged with distinct temporal frequencies and we quantified spectral response components associated with the individual stimuli (self terms) and responses due to interaction between stimuli (intermodulation terms). In early visual cortex, masking alters the self terms in a manner consistent with a reduction of input contrast. We also identify a novel signature of masking: a robust intermodulation term that peaks when the test and mask stimuli have equal contrast and disappears when they are widely different. We fit all of our data simultaneously with family of a divisive gain control models that differed only in their dynamics. Models with either very short or very long temporal integration constants for the gain pool performed worse than a model with an integration time of ∼30 ms. Finally, the absolute magnitudes of the response were controlled by the ratio of the stimulus contrasts, not their absolute values. This contrast-contrast invariance suggests that many neurons in early visual cortex code relative rather than absolute contrast. Together, these results provide a more complete description of masking within the normalization framework of contrast gain control and suggest that contrast normalization accomplishes multiple functional goals.

  9. Optical and microwave detection using Bi-Sr-Ca-Cu-O thin films

    NASA Technical Reports Server (NTRS)

    Grabow, B. E.; Sova, R. M.; Boone, B. G.; Moorjani, K.; Kim, B. F.; Bohandy, J.; Adrian, F.; Green, W. J.

    1990-01-01

    Recent progress at the Johns Hopkins University Applied Physics Laboratory (JHU/APL) in the development of optical and microwave detectors using high temperature superconducting thin films is described. Several objectives of this work have been accomplished, including: deposition of Bi-Sr-Ca-Cu-O thin films by laser abation processing (LAP); development of thin film patterning techniques, including in situ masking, wet chemical etching and laser patterning; measurements of bolometric and non-bolometric signatures in patterned Bi-Sr-Ca-Cu-O films using optical and microwave sources, respectively; analysis and design of an optimized bolometer through computer simulation, and investigation of its use in a Fourier transform spectrometer. The focus here is primarily on results from the measurement of the bolometric and non-bolometric response.

  10. Optical and microwave detection using Bi-Sr-Ca-Cu-O thin films

    NASA Technical Reports Server (NTRS)

    Grabow, B. E.; Sova, R. M.; Boone, B. G.; Moorjani, K.; Kim, B. F.; Bohandy, J.; Adrian, F.; Green, W. J.

    1991-01-01

    Recent progress at the Johns Hopkins University Applied Physics Laboratory (JHU/APL) in the development of optical and microwave detectors using high temperature superconducting thin films is described. Several objectives of this work have been accomplished, including: deposition of Bi-Sr-Ca-Cu-O thin films by laser abation processing (LAP); development of thin film patterning techniques, including in situ masking, wet chemical etching, and laser patterning; measurements of bolometric and non-bolometric signatures in patterned Bi-Sr-Ca-Cu-O films using optical and microwave sources, respectively; analysis and design of an optimized bolometer through computer simulation; and investigation of its use in a Fourier transform spectrometer. The focus here is primarily on results from the measurement of the bolometric and non-bolometric response.

  11. The effect of SF6 addition in a Cl2/Ar inductively coupled plasma for deep titanium etching

    NASA Astrophysics Data System (ADS)

    Laudrel, E.; Tillocher, T.; Meric, Y.; Lefaucheux, P.; Boutaud, B.; Dussart, R.

    2018-05-01

    Titanium is a material of interest for the biomedical field and more particularly for body implantable devices. Titanium deep etching by plasma was carried out in an inductively coupled plasma with a chlorine-based chemistry for the fabrication of titanium-based microdevices. Bulk titanium etch rate was first studied in Cl2/Ar plasma mixture versus the source power and the self-bias voltage. The plasma was characterized by Langmuir probe and by optical emission spectroscopy. The addition of SF6 in the plasma mixture was investigated. Titanium etch rate was optimized and reached a value of 2.4 µm · min-1. The nickel hard mask selectivity was also enhanced. The etched titanium surface roughness was reduced significantly.

  12. SpcAudace: Spectroscopic processing and analysis package of Audela software

    NASA Astrophysics Data System (ADS)

    Mauclaire, Benjamin

    2017-11-01

    SpcAudace processes long slit spectra with automated pipelines and performs astrophysical analysis of the latter data. These powerful pipelines do all the required steps in one pass: standard preprocessing, masking of bad pixels, geometric corrections, registration, optimized spectrum extraction, wavelength calibration and instrumental response computation and correction. Both high and low resolution long slit spectra are managed for stellar and non-stellar targets. Many types of publication-quality figures can be easily produced: pdf and png plots or annotated time series plots. Astrophysical quantities can be derived from individual or large amount of spectra with advanced functions: from line profile characteristics to equivalent width and periodogram. More than 300 documented functions are available and can be used into TCL scripts for automation. SpcAudace is based on Audela open source software.

  13. Plasma-Induced, Self-Masking, One-Step Approach to an Ultrabroadband Antireflective and Superhydrophilic Subwavelength Nanostructured Fused Silica Surface.

    PubMed

    Ye, Xin; Shao, Ting; Sun, Laixi; Wu, Jingjun; Wang, Fengrui; He, Junhui; Jiang, Xiaodong; Wu, Wei-Dong; Zheng, Wanguo

    2018-04-25

    In this work, antireflective and superhydrophilic subwavelength nanostructured fused silica surfaces have been created by one-step, self-masking reactive ion etching (RIE). Bare fused silica substrates with no mask were placed in a RIE vacuum chamber, and then nanoscale fluorocarbon masks and subwavelength nanostructures (SWSs) automatically formed on these substrate after the appropriate RIE plasma process. The mechanism of plasma-induced self-masking SWS has been proposed in this paper. Plasma parameter effects on the morphology of SWS have been investigated to achieve perfect nanocone-like SWS for excellent antireflection, including process time, reactive gas, and pressure of the chamber. Optical properties, i.e., antireflection and optical scattering, were simulated by the finite difference time domain (FDTD) method. Calculated data agree well with the experiment results. The optimized SWS show ultrabroadband antireflective property (up to 99% from 500 to 1360 nm). An excellent improvement of transmission was achieved for the deep-ultraviolet (DUV) range. The proposed low-cost, highly efficient, and maskless method was applied to achieve ultrabroadband antireflective and superhydrophilic SWSs on a 100 mm optical window, which promises great potential for applications in the automotive industry, goggles, and optical devices.

  14. Phase-shifting coronagraph

    NASA Astrophysics Data System (ADS)

    Hénault, François; Carlotti, Alexis; Vérinaud, Christophe

    2017-09-01

    With the recent commissioning of ground instruments such as SPHERE or GPI and future space observatories like WFIRST-AFTA, coronagraphy should probably become the most efficient tool for identifying and characterizing extrasolar planets in the forthcoming years. Coronagraphic instruments such as Phase mask coronagraphs (PMC) are usually based on a phase mask or plate located at the telescope focal plane, spreading the starlight outside the diameter of a Lyot stop that blocks it. In this communication is investigated the capability of a PMC to act as a phase-shifting wavefront sensor for better control of the achieved star extinction ratio in presence of the coronagraphic mask. We discuss the two main implementations of the phase-shifting process, either introducing phase-shifts in a pupil plane and sensing intensity variations in an image plane, or reciprocally. Conceptual optical designs are described in both cases. Numerical simulations allow for better understanding of the performance and limitations of both options, and optimizing their fundamental parameters. In particular, they demonstrate that the phase-shifting process is a bit more efficient when implemented into an image plane, and is compatible with the most popular phase masks currently employed, i.e. fourquadrants and vortex phase masks.

  15. Use of MODIS Satellite Data to Evaluate Juniperus spp. Pollen Phenology to Support a Pollen Dispersal Model, PREAM, to Support Public Health Allergy Alerts

    NASA Technical Reports Server (NTRS)

    Luvall, J. C.; Sprigg, W.; Levetin, E.; Huete, A.; Nickovic, S.; Pejanovic, G. A.; Vukovic, A.; VandeWater, P.; Budge, A.; Hudspeth, W.; hide

    2012-01-01

    Juniperus spp. pollen is a significant aeroallergen that can be transported 200-600 km from the source. Local observations of Juniperus spp. phenology may not be consistent with the timing and source of pollen collected by pollen sampling instruments. Methods: The Dust REgional Atmospheric Model (DREAM)is a verified model for atmospheric dust transport modeling using MODIS data products to identify source regions and quantities of dust. We successfully modified the DREAM model to incorporate pollen transport (PREAM) and used MODIS satellite images to develop Juniperus ashei pollen input source masks. The Pollen Release Potential Source Map, also referred to as a source mask in model applications, may use different satellite platforms and sensors and a variety of data sets other than the USGS GAP data we used to map J. ashei cover type. MODIS derived percent tree cover is obtained from MODIS Vegetation Continuous Fields (VCF) product (collection 3 and 4, MOD44B, 500 and 250 m grid resolution). We use updated 2010 values to calculate pollen concentration at source (J. ashei ). The original MODIS derived values are converted from native approx. 250 m to 990m (approx. 1 km) for the calculation of a mask to fit the model (PREAM) resolution. Results: The simulation period is chosen following the information that in the last 2 weeks of December 2010. The PREAM modeled near-surface concentrations (Nm-3) shows the transport patterns of J. ashei pollen over a 5 day period (Fig. 2). Typical scales of the simulated transport process are regional.

  16. Pharmaceutical optimization of lipid-based dosage forms for the improvement of taste-masking, chemical stability and solubilizing capacity of phenobarbital.

    PubMed

    Monteagudo, Ezequiel; Langenheim, Mariana; Salerno, Claudia; Buontempo, Fabián; Bregni, Carlos; Carlucci, Adriana

    2014-06-01

    Microemulsions (MEs) and self-emulsifying drug delivery systems (SEEDS) containing phenobarbital (Phe) were developed to improve its chemical stability, solubilizing capacity and taste-masking in oral liquid dosage forms. Cremophor® RH40 and Labrasol® were used as surfactants for the screening of ME regions, Capmul® MCM L, Captex® 355, Imwitor® 408, Myglyol® 840 and Isopropyl myristate were the oil phases assayed; Transcutol® P, Polyethylene-glycol 400, glycerol, Propylene-glycol and ethanol the cosurfactants. Phe stability assay was carried out (20:4:20:56% and 20:4:35:41% (w/w); surfactant:oily phase:cosurfactant:water) for both surfactants; only one containing ethanol showed significant dismissing in its drug content. Solubility capacity for these selected formulations were also evaluated, an amount between 17 and 58 mg/mL of Phe could be loaded. At last, an optimized ME formulation with Cremophor® RH40 20%, Capmul® MCM L 4%, PEG 400 35% and sucralose 2% (w/w) was chosen in order to optimize taste-masking using an electronic tongue. Strawberry along with banana and tutti-frutti flavors plus mint flavor proved to be the best ones. Labrasol-based pre-concentrates were tested for (micro)emulsifying properties; all of them resulted to behave as SEDDS. In summary, a rationale experimental design conducted to an optimized ME for Phe oral pediatric administration which was able to load 5-fold times the currently used dose (4 mg/mL), with no sign of physical or chemical instability and with improved taste; SEDDS for capsule filling were also obtained. The biopharmaceutical advantages described for these dosage forms encourage furthering in vivo evaluation.

  17. Masking disrupts reentrant processing in human visual cortex.

    PubMed

    Fahrenfort, J J; Scholte, H S; Lamme, V A F

    2007-09-01

    In masking, a stimulus is rendered invisible through the presentation of a second stimulus shortly after the first. Over the years, authors have typically explained masking by postulating some early disruption process. In these feedforward-type explanations, the mask somehow "catches up" with the target stimulus, disrupting its processing either through lateral or interchannel inhibition. However, studies from recent years indicate that visual perception--and most notably visual awareness itself--may depend strongly on cortico-cortical feedback connections from higher to lower visual areas. This has led some researchers to propose that masking derives its effectiveness from selectively interrupting these reentrant processes. In this experiment, we used electroencephalogram measurements to determine what happens in the human visual cortex during detection of a texture-defined square under nonmasked (seen) and masked (unseen) conditions. Electro-encephalogram derivatives that are typically associated with reentrant processing turn out to be absent in the masked condition. Moreover, extrastriate visual areas are still activated early on by both seen and unseen stimuli, as shown by scalp surface Laplacian current source-density maps. This conclusively shows that feedforward processing is preserved, even when subject performance is at chance as determined by objective measures. From these results, we conclude that masking derives its effectiveness, at least partly, from disrupting reentrant processing, thereby interfering with the neural mechanisms of figure-ground segmentation and visual awareness itself.

  18. Stress engineering in GaN structures grown on Si(111) substrates by SiN masking layer application

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

    Szymański, Tomasz, E-mail: tomasz.szymanski@pwr.edu.pl; Wośko, Mateusz; Paszkiewicz, Bogdan

    2015-07-15

    GaN layers without and with an in-situ SiN mask were grown by using metal organic vapor phase epitaxy for three different approaches used in GaN on silicon(111) growth, and the physical and optical properties of the GaN layers were studied. For each approach applied, GaN layers of 1.4 μm total thickness were grown, using silan SiH{sub 4} as Si source in order to grow Si{sub x}N{sub x} masking layer. The optical micrographs, scanning electron microscope images, and atomic force microscope images of the grown samples revealed cracks for samples without SiN mask, and micropits, which were characteristic for the samples grownmore » with SiN mask. In situ reflectance signal traces were studied showing a decrease of layer coalescence time and higher degree of 3D growth mode for samples with SiN masking layer. Stress measurements were conducted by two methods—by recording micro-Raman spectra and ex-situ curvature radius measurement—additionally PLs spectra were obtained revealing blueshift of PL peak positions with increasing stress. The authors have shown that a SiN mask significantly improves physical and optical properties of GaN multilayer systems reducing stress in comparison to samples grown applying the same approaches but without SiN masking layer.« less

  19. Topology-changing shape optimization with the genetic algorithm

    NASA Astrophysics Data System (ADS)

    Lamberson, Steven E., Jr.

    The goal is to take a traditional shape optimization problem statement and modify it slightly to allow for prescribed changes in topology. This modification enables greater flexibility in the choice of parameters for the topology optimization problem, while improving the direct physical relevance of the results. This modification involves changing the optimization problem statement from a nonlinear programming problem into a form of mixed-discrete nonlinear programing problem. The present work demonstrates one possible way of using the Genetic Algorithm (GA) to solve such a problem, including the use of "masking bits" and a new modification to the bit-string affinity (BSA) termination criterion specifically designed for problems with "masking bits." A simple ten-bar truss problem proves the utility of the modified BSA for this type of problem. A more complicated two dimensional bracket problem is solved using both the proposed approach and a more traditional topology optimization approach (Solid Isotropic Microstructure with Penalization or SIMP) to enable comparison. The proposed approach is able to solve problems with both local and global constraints, which is something traditional methods cannot do. The proposed approach has a significantly higher computational burden --- on the order of 100 times larger than SIMP, although the proposed approach is able to offset this with parallel computing.

  20. Engineering the on-axis intensity of Bessel beam by a feedback tuning loop

    NASA Astrophysics Data System (ADS)

    Li, Runze; Yu, Xianghua; Yang, Yanlong; Peng, Tong; Yao, Baoli; Zhang, Chunmin; Ye, Tong

    2018-02-01

    The Bessel beam belongs to a typical class of non-diffractive optical fields that are characterized by their invariant focal profiles along the propagation direction. However, ideal Bessel beams only rigorously exist in theory; Bessel beams generated in the lab are quasi-Bessel beams with finite focal extensions and varying intensity profiles along the propagation axis. The ability to engineer the on-axis intensity profile to the desired shape is essential for many applications. Here we demonstrate an iterative optimization-based approach to engineering the on-axis intensity of Bessel beams. The genetic algorithm is used to demonstrate this approach. Starting with a traditional axicon phase mask, in the design process, the computed on-axis beam profile is fed into a feedback tuning loop of an iterative optimization process, which searches for an optimal radial phase distribution that can generate a generalized Bessel beam with the desired onaxis intensity profile. The experimental implementation involves a fine-tuning process that adjusts the originally targeted profile so that the optimization process can optimize the phase mask to yield an improved on-axis profile. Our proposed method has been demonstrated in engineering several zeroth-order Bessel beams with customized on-axis profiles. High accuracy and high energy throughput merit its use in many applications.

  1. Blood pressure and calf muscle oxygen extraction during plantar flexion exercise in peripheral artery disease.

    PubMed

    Luck, J Carter; Miller, Amanda J; Aziz, Faisal; Radtka, John F; Proctor, David N; Leuenberger, Urs A; Sinoway, Lawrence I; Muller, Matthew D

    2017-07-01

    Peripheral artery disease (PAD) is an atherosclerotic vascular disease that affects 200 million people worldwide. Although PAD primarily affects large arteries, it is also associated with microvascular dysfunction, an exaggerated blood pressure (BP) response to exercise, and high cardiovascular mortality. We hypothesized that fatiguing plantar flexion exercise that evokes claudication elicits a greater reduction in skeletal muscle oxygenation (SmO 2 ) and a higher rise in BP in PAD compared with age-matched healthy subjects, but low-intensity steady-state plantar flexion elicits similar responses between groups. In the first experiment, eight patients with PAD and eight healthy controls performed fatiguing plantar flexion exercise (from 0.5 to 7 kg for up to 14 min). In the second experiment, seven patients with PAD and seven healthy controls performed low-intensity plantar flexion exercise (2.0 kg for 14 min). BP, heart rate (HR), and SmO 2 were measured continuously using near-infrared spectroscopy (NIRS). SmO 2 is the ratio of oxygenated hemoglobin to total hemoglobin, expressed as a percent. At fatigue, patients with PAD had a greater increase in mean arterial BP (18 ± 2 vs. vs. 10 ± 2 mmHg, P = 0.029) and HR (14 ± 2 vs. 6 ± 2 beats/min, P = 0.033) and a greater reduction in SmO 2 (-54 ± 10 vs. -12 ± 4%, P = 0.001). However, both groups had similar physiological responses to low-intensity, nonpainful plantar flexion exercise. These data suggest that patients with PAD have altered oxygen uptake and/or utilization during fatiguing exercise coincident with an augmented BP response. NEW & NOTEWORTHY In this laboratory study, patients with peripheral artery disease performed plantar flexion exercise in the supine posture until symptoms of claudication occurred. Relative to age- and sex-matched healthy subjects we found that patients had a higher blood pressure response, a higher heart rate response, and a greater reduction in skeletal muscle oxygenation as determined by near-infrared spectroscopy. Our data suggest that muscle ischemia contributes to the augmented exercise pressor reflex in peripheral artery disease. Copyright © 2017 the American Physiological Society.

  2. Active-duty military service members’ visual representations of PTSD and TBI in masks

    PubMed Central

    Walker, Melissa S.; Kaimal, Girija; Gonzaga, Adele M. L.; Myers-Coffman, Katherine A.; DeGraba, Thomas J.

    2017-01-01

    ABSTRACT Active-duty military service members have a significant risk of sustaining physical and psychological trauma resulting in traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD). Within an interdisciplinary treatment approach at the National Intrepid Center of Excellence, service members participated in mask making during art therapy sessions. This study presents an analysis of the mask-making experiences of service members (n = 370) with persistent symptoms from combat- and mission-related TBI, PTSD, and other concurrent mood issues. Data sources included mask images and therapist notes collected over a five-year period. The data were coded and analyzed using grounded theory methods. Findings indicated that mask making offered visual representations of the self related to individual personhood, relationships, community, and society. Imagery themes referenced the injury, relational supports/losses, identity transitions/questions, cultural metaphors, existential reflections, and conflicted sense of self. These visual insights provided an increased understanding of the experiences of service members, facilitating their recovery. PMID:28452610

  3. Active-duty military service members' visual representations of PTSD and TBI in masks.

    PubMed

    Walker, Melissa S; Kaimal, Girija; Gonzaga, Adele M L; Myers-Coffman, Katherine A; DeGraba, Thomas J

    2017-12-01

    Active-duty military service members have a significant risk of sustaining physical and psychological trauma resulting in traumatic brain injury (TBI) and post-traumatic stress disorder (PTSD). Within an interdisciplinary treatment approach at the National Intrepid Center of Excellence, service members participated in mask making during art therapy sessions. This study presents an analysis of the mask-making experiences of service members (n = 370) with persistent symptoms from combat- and mission-related TBI, PTSD, and other concurrent mood issues. Data sources included mask images and therapist notes collected over a five-year period. The data were coded and analyzed using grounded theory methods. Findings indicated that mask making offered visual representations of the self related to individual personhood, relationships, community, and society. Imagery themes referenced the injury, relational supports/losses, identity transitions/questions, cultural metaphors, existential reflections, and conflicted sense of self. These visual insights provided an increased understanding of the experiences of service members, facilitating their recovery.

  4. ILT optimization of EUV masks for sub-7nm lithography

    NASA Astrophysics Data System (ADS)

    Hooker, Kevin; Kuechler, Bernd; Kazarian, Aram; Xiao, Guangming; Lucas, Kevin

    2017-06-01

    The 5nm and 7nm technology nodes will continue recent scaling trends and will deliver significantly smaller minimum features, standard cell areas and SRAM cell areas vs. the 10nm node. There are tremendous economic pressures to shrink each subsequent technology, though in a cost-effective and performance enhancing manner. IC manufacturers are eagerly awaiting EUV so that they can more aggressively shrink their technology than they could by using complicated MPT. The current 0.33NA EUV tools and processes also have their patterning limitations. EUV scanner lenses, scanner sources, masks and resists are all relatively immature compared to the current lithography manufacturing baseline of 193i. For example, lens aberrations are currently several times larger (as a function of wavelength) in EUV scanners than for 193i scanners. Robustly patterning 16nm L/S fully random logic metal patterns and 40nm pitch random logic rectangular contacts with 0.33NA EUV are tough challenges that will benefit from advanced OPC/RET. For example, if an IC manufacturer can push single exposure device layer resolution 10% tighter using improved ILT to avoid using DPT, there will be a significant cost and process complexity benefit to doing so. ILT is well known to have considerable benefits in finding flexible 193i mask pattern solutions to improve process window, improve 2D CD control, improve resolution in low K1 lithography regime and help to delay the introduction of DPT. However, ILT has not previously been applied to EUV lithography. In this paper, we report on new developments which extend ILT method to EUV lithography and we characterize the benefits seen vs. traditional EUV OPC/RET methods.

  5. Measurements from preterm infants to guide face mask size.

    PubMed

    O'Shea, Joyce E; Thio, Marta; Owen, Louise S; Wong, Connie; Dawson, Jennifer A; Davis, Peter G

    2016-07-01

    International guidelines recommend that an appropriately sized face mask for providing positive pressure ventilation should cover the mouth and nose but not the eyes and should not overlap the chin. This study aimed to measure the dimensions of preterm infants' faces and compare these with the size of the most commonly available face masks (external diameter 50 mm) and the smallest masks available (external diameters 35 and 42 mm). Infants 24-33 weeks' postmenstrual age (PMA) were photographed in a standardised manner. Images were analysed using ImageJ software (National Institute of Health, USA) to calculate the distance from the nasofrontal groove to the mental protuberance. This facial measurement corresponds to the external diameter of an optimally fitting mask. A cohort of 107 infants between 24 and 33 weeks' gestational age, including at least 10 infants per week of gestation, was photographed within 72 h after birth and weekly until 33 weeks' PMA. 347 photographs were analysed. Infants of 24, 26, 28, 30 and 32 weeks' PMA had mean (SD) facial measurements of 32 (2), 36 (3), 38 (4), 41 (2) and 43 (4) mm, respectively. There were no significant differences when examined by gender or when small for gestational age infants were excluded. The smallest size of some brands of mask is too large for many preterm infants. Masks of 35 mm diameter are suitable for infants <29 weeks' PMA or 1000 g. Masks of 42 mm diameter are suitable for infants 27-33 weeks' PMA or 750-2500 g. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  6. AN IMAGE-PLANE ALGORITHM FOR JWST'S NON-REDUNDANT APERTURE MASK DATA

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

    Greenbaum, Alexandra Z.; Pueyo, Laurent; Sivaramakrishnan, Anand

    2015-01-10

    The high angular resolution technique of non-redundant masking (NRM) or aperture masking interferometry (AMI) has yielded images of faint protoplanetary companions of nearby stars from the ground. AMI on James Webb Space Telescope (JWST)'s Near Infrared Imager and Slitless Spectrograph (NIRISS) has a lower thermal background than ground-based facilities and does not suffer from atmospheric instability. NIRISS AMI images are likely to have 90%-95% Strehl ratio between 2.77 and 4.8 μm. In this paper we quantify factors that limit the raw point source contrast of JWST NRM. We develop an analytic model of the NRM point spread function which includesmore » different optical path delays (pistons) between mask holes and fit the model parameters with image plane data. It enables a straightforward way to exclude bad pixels, is suited to limited fields of view, and can incorporate effects such as intra-pixel sensitivity variations. We simulate various sources of noise to estimate their effect on the standard deviation of closure phase, σ{sub CP} (a proxy for binary point source contrast). If σ{sub CP} < 10{sup –4} radians—a contrast ratio of 10 mag—young accreting gas giant planets (e.g., in the nearby Taurus star-forming region) could be imaged with JWST NIRISS. We show the feasibility of using NIRISS' NRM with the sub-Nyquist sampled F277W, which would enable some exoplanet chemistry characterization. In the presence of small piston errors, the dominant sources of closure phase error (depending on pixel sampling, and filter bandwidth) are flat field errors and unmodeled variations in intra-pixel sensitivity. The in-flight stability of NIRISS will determine how well these errors can be calibrated by observing a point source. Our results help develop efficient observing strategies for space-based NRM.« less

  7. Development for 2D pattern quantification method on mask and wafer

    NASA Astrophysics Data System (ADS)

    Matsuoka, Ryoichi; Mito, Hiroaki; Toyoda, Yasutaka; Wang, Zhigang

    2010-03-01

    We have developed the effective method of mask and silicon 2-dimensional metrology. The aim of this method is evaluating the performance of the silicon corresponding to Hotspot on a mask. The method adopts a metrology management system based on DBM (Design Based Metrology). This is the high accurate contouring created by an edge detection algorithm used in mask CD-SEM and silicon CD-SEM. Currently, as semiconductor manufacture moves towards even smaller feature size, this necessitates more aggressive optical proximity correction (OPC) to drive the super-resolution technology (RET). In other words, there is a trade-off between highly precise RET and mask manufacture, and this has a big impact on the semiconductor market that centers on the mask business. 2-dimensional Shape quantification is important as optimal solution over these problems. Although 1-dimensional shape measurement has been performed by the conventional technique, 2-dimensional shape management is needed in the mass production line under the influence of RET. We developed the technique of analyzing distribution of shape edge performance as the shape management technique. On the other hand, there is roughness in the silicon shape made from a mass-production line. Moreover, there is variation in the silicon shape. For this reason, quantification of silicon shape is important, in order to estimate the performance of a pattern. In order to quantify, the same shape is equalized in two dimensions. And the method of evaluating based on the shape is popular. In this study, we conducted experiments for averaging method of the pattern (Measurement Based Contouring) as two-dimensional mask and silicon evaluation technique. That is, observation of the identical position of a mask and a silicon was considered. It is possible to analyze variability of the edge of the same position with high precision. The result proved its detection accuracy and reliability of variability on two-dimensional pattern (mask and silicon) and is adaptable to following fields of mask quality management. - Estimate of the correlativity of shape variability and a process margin. - Determination of two-dimensional variability of pattern. - Verification of the performance of the pattern of various kinds of Hotspots. In this report, we introduce the experimental results and the application. We expect that the mask measurement and the shape control on mask production will make a huge contribution to mask yield-enhancement and that the DFM solution for mask quality control process will become much more important technology than ever. It is very important to observe the shape of the same location of Design, Mask, and Silicon in such a viewpoint.

  8. SEMATECH EUVL mask program status

    NASA Astrophysics Data System (ADS)

    Yun, Henry; Goodwin, Frank; Huh, Sungmin; Orvek, Kevin; Cha, Brian; Rastegar, Abbas; Kearney, Patrick

    2009-04-01

    As we approach the 22nm half-pitch (hp) technology node, the industry is rapidly running out of patterning options. Of the several lithography techniques highlighted in the International Technology Roadmap for Semiconductors (ITRS), the leading contender for the 22nm hp insertion is extreme ultraviolet lithography (EUVL). Despite recent advances with EUV resist and improvements in source power, achieving defect free EUV mask blank and enabling the EUV mask infrastructure still remain critical issues. To meet the desired EUV high volume manufacturing (HVM) insertion target date of 2013, these obstacles must be resolved on a timely bases. Many of the EUV mask related challenges remain in the pre-competitive stage and a collaborative industry based consortia, such as SEMATECH can play an important role to enable the EUVL landscape. SEMATECH based in Albany, NY is an international consortium representing several of the largest manufacturers in the semiconductor market. Full members include Intel, Samsung, AMD, IBM, Panasonic, HP, TI, UMC, CNSE (College of Nanoscience and Engineering), and Fuller Road Management. Within the SEMATECH lithography division a major thrust is centered on enabling the EUVL ecosystem from mask development, EUV resist development and addressing EUV manufacturability concerns. An important area of focus for the SEMATECH mask program has been the Mask Blank Development Center (MBDC). At the MBDC key issues in EUV blank development such as defect reduction and inspection capabilities are actively pursued together with research partners, key suppliers and member companies. In addition the mask program continues a successful track record of working with the mask community to manage and fund critical mask tools programs. This paper will highlight recent status of mask projects and longer term strategic direction at the MBDC. It is important that mask technology be ready to support pilot line development HVM by 2013. In several areas progress has been made but a continued collaborative effort will be needed along with timely infrastructure investments to meet these challenging goals.

  9. Prognostic value of hedgehog signaling pathway in digestive system cancers: A systematic review and meta-analysis.

    PubMed

    Wang, Yihan; Peng, Qian; Jia, Hongyuan; Du, Xiao

    2016-01-01

    The Hedgehog (Hh) signaling pathway has recently been reported to be associated with the prognosis of digestive system cancers. However, the results are inconsistent. This study aimed to investigate the association between Hh pathway components and survival outcomes in patients with digestive system cancers. We conducted a comprehensive retrieval in PubMed, EMBASE and Cochrane library for relevant literatures until May 1st, 2015. The pooled hazard ratios (HRs) for overall survival (OS) and disease-free survival (DFS) with 95% confidence intervals (CIs) were calculated to clarify the prognostic value of Hh pathway components, including Shh, Gli1, Gli2, Smo and Ptch1. A total of 16 eligible articles with 3222 patients were included in the meta-analysis. Pooled HR suggested that over-expression of Shh and Gli1 were both associated with poor OS (HR = 1.87, 95% CI: 1.14-3.07 and HR = 1.96, 95% CI: 1.66-2.32, respectively) and DFS (HR = 2.37, 95% CI: 1.19-4.72 and HR = 2.18, 95% CI: 1.61-2.96, respectively). In addition, over-expression of Smo was associated with poor DFS (HR = 1.38, 95% CI: 1.08-1.75). This study reveals that over-expressed Hh pathway components, including Shh, Gli1 and Smo, are associated with poor prognosis in digestive system cancer patients. Hh signaling pathway may become a potential therapeutic target in digestive system cancers.

  10. Portuguese propolis disturbs glycolytic metabolism of human colorectal cancer in vitro

    PubMed Central

    2013-01-01

    Background Propolis is a resin collected by bees from plant buds and exudates, which is further processed through the activity of bee enzymes. Propolis has been shown to possess many biological and pharmacological properties, such as antimicrobial, antioxidant, immunostimulant and antitumor activities. Due to this bioactivity profile, this resin can become an alternative, economic and safe source of natural bioactive compounds. Antitumor action has been reported in vitro and in vivo for propolis extracts or its isolated compounds; however, Portuguese propolis has been little explored. The aim of this work was to evaluate the in vitro antitumor activity of Portuguese propolis on the human colon carcinoma cell line HCT-15, assessing the effect of different fractions (hexane, chloroform and ethanol residual) of a propolis ethanol extract on cell viability, proliferation, metabolism and death. Methods Propolis from Angra do Heroísmo (Azores) was extracted with ethanol and sequentially fractionated in solvents with increasing polarity, n-hexane and chloroform. To assess cell viability, cell proliferation and cell death, Sulforhodamine B, BrDU incorporation assay and Anexin V/Propidium iodide were used, respectively. Glycolytic metabolism was estimated using specific kits. Results All propolis samples exhibited a cytotoxic effect against tumor cells, in a dose- and time-dependent way. Chloroform fraction, the most enriched in phenolic compounds, appears to be the most active, both in terms of inhibition of viability and cell death. Data also show that this cytotoxicity involves disturbance in tumor cell glycolytic metabolism, seen by a decrease in glucose consumption and lactate production. Conclusion Our results show that Portuguese propolis from Angra do Heroísmo (Azores) can be a potential therapeutic agent against human colorectal cancer. PMID:23870175

  11. Crater-lake Santa Maria del Oro as a Pristine Reference for Persistent Organic Pollutants (POP' s) and Heavy Metals Content in Environmental Investigations in Western Mexico (Project Conacyt-Semarnat 2002-C01-0463, in Progress).

    NASA Astrophysics Data System (ADS)

    Zarate-Del Valle, P. F.; Gomez-Hermosillo, C. M.; Venegas-Garcia, D. J.

    2007-12-01

    Santa Maria del Oro Lake ( SMO) (21.37° N, 104.57° W; 750 m a.s.l.) is a quaternary crater-lake located at western Mexico in the natural border between two geological provinces: the plio-quaternary Trans-Mexican Volcanic Belt and the oligo-miocenic silicic volcanic province Sierra Madre Occidental. SMO, a tropical freshwater lake, is a warm-monomictic lake having a diameter of ca. 2 km and a mean depth at the depocenter of ca. 60 m, where three benthos cores were recovered. Contents of POP' s, total inorganic carbon (TIC), total organic carbon (TOC) and heavy metals were analyzed. Geochemistry and mineralogy also were studied in shallow sediments which corresponded to the decade of 50-60's, otherwise the beginning of industrial development of central Mexico; which is considered the possible source of emission of POP' s and heavy metals. Dioxin, furan, plaguicides and PCB' s contents were analyzed by a GC-MS applying USEPA methods. In the first 40 cm (n= 20) of the sedimentary column ( SC) the absence of POP' s was evidenced, applying a method detection limit ( MDL) of 5 μ g/ml for dioxin, furan and PCB' s. For plaguicides like chlordane and toxaphene the MDL was 0.5 μ g/ml and for plaguicides like DDT, aldrin, endrin, dieldrin, heptachlore and mirex the MDL was 5 μ g/ml. The MDL for HCB was 1 μ g/ml. The average (n= 30) for TIC, TOC and total carbon (TC) for the first 40 cm of the SC is as follows: TIC 2.4 %, TOC 3.7 % and TC 6.12 %. The average (n= 20) content (in ppm) of heavy metals for the first 20 cm of the SC is as follows: As 5.97, Cr 27.54, Cu 16.31, Ni 12.29, Pb 21.35 and Zn 82.46. These contents are roughly similar to the clarke of these metals in volcanic rocks. After the criteria of severe effect level ( SEL) of heavy metal in sediments, the content of these metals is below SEL levels. These results permit us to conclude that the sediments of SMO can be considered in unaffected state with respect to antropogenic contamination like POP' s and heavy metals. Consequently, Santa Maria del Oro Lake can be considered as a pristine reference in paleo-ecological and environmental investigations in western Mexico.

  12. Face mask sampling for the detection of Mycobacterium tuberculosis in expelled aerosols.

    PubMed

    Williams, Caroline M L; Cheah, Eddy S G; Malkin, Joanne; Patel, Hemu; Otu, Jacob; Mlaga, Kodjovi; Sutherland, Jayne S; Antonio, Martin; Perera, Nelun; Woltmann, Gerrit; Haldar, Pranabashis; Garton, Natalie J; Barer, Michael R

    2014-01-01

    Although tuberculosis is transmitted by the airborne route, direct information on the natural output of bacilli into air by source cases is very limited. We sought to address this through sampling of expelled aerosols in face masks that were subsequently analyzed for mycobacterial contamination. In series 1, 17 smear microscopy positive patients wore standard surgical face masks once or twice for periods between 10 minutes and 5 hours; mycobacterial contamination was detected using a bacteriophage assay. In series 2, 19 patients with suspected tuberculosis were studied in Leicester UK and 10 patients with at least one positive smear were studied in The Gambia. These subjects wore one FFP30 mask modified to contain a gelatin filter for one hour; this was subsequently analyzed by the Xpert MTB/RIF system. In series 1, the bacteriophage assay detected live mycobacteria in 11/17 patients with wearing times between 10 and 120 minutes. Variation was seen in mask positivity and the level of contamination detected in multiple samples from the same patient. Two patients had non-tuberculous mycobacterial infections. In series 2, 13/20 patients with pulmonary tuberculosis produced positive masks and 0/9 patients with extrapulmonary or non-tuberculous diagnoses were mask positive. Overall, 65% of patients with confirmed pulmonary mycobacterial infection gave positive masks and this included 3/6 patients who received diagnostic bronchoalveolar lavages. Mask sampling provides a simple means of assessing mycobacterial output in non-sputum expectorant. The approach shows potential for application to the study of airborne transmission and to diagnosis.

  13. Face Mask Sampling for the Detection of Mycobacterium tuberculosis in Expelled Aerosols

    PubMed Central

    Malkin, Joanne; Patel, Hemu; Otu, Jacob; Mlaga, Kodjovi; Sutherland, Jayne S.; Antonio, Martin; Perera, Nelun; Woltmann, Gerrit; Haldar, Pranabashis; Garton, Natalie J.; Barer, Michael R.

    2014-01-01

    Background Although tuberculosis is transmitted by the airborne route, direct information on the natural output of bacilli into air by source cases is very limited. We sought to address this through sampling of expelled aerosols in face masks that were subsequently analyzed for mycobacterial contamination. Methods In series 1, 17 smear microscopy positive patients wore standard surgical face masks once or twice for periods between 10 minutes and 5 hours; mycobacterial contamination was detected using a bacteriophage assay. In series 2, 19 patients with suspected tuberculosis were studied in Leicester UK and 10 patients with at least one positive smear were studied in The Gambia. These subjects wore one FFP30 mask modified to contain a gelatin filter for one hour; this was subsequently analyzed by the Xpert MTB/RIF system. Results In series 1, the bacteriophage assay detected live mycobacteria in 11/17 patients with wearing times between 10 and 120 minutes. Variation was seen in mask positivity and the level of contamination detected in multiple samples from the same patient. Two patients had non-tuberculous mycobacterial infections. In series 2, 13/20 patients with pulmonary tuberculosis produced positive masks and 0/9 patients with extrapulmonary or non-tuberculous diagnoses were mask positive. Overall, 65% of patients with confirmed pulmonary mycobacterial infection gave positive masks and this included 3/6 patients who received diagnostic bronchoalveolar lavages. Conclusion Mask sampling provides a simple means of assessing mycobacterial output in non-sputum expectorant. The approach shows potential for application to the study of airborne transmission and to diagnosis. PMID:25122163

  14. Application of advanced structure to multi-tone mask for FPD process

    NASA Astrophysics Data System (ADS)

    Song, Jin-Han; Jeong, Jin-Woong; Kim, Kyu-Sik; Jeong, Woo-Gun; Yun, Sang-Pil; Lee, Dong-Heok; Choi, Sang-Soo

    2017-07-01

    In accordance with improvement of FPD technology, masks such as phase shift mask (PSM) and multi-tone mask (MTM) for a particular purpose also have been developed. Above all, the MTM consisted of more than tri-tone transmittance has a substantial advantage which enables to reduce the number of mask demand in FPD fabrication process contrast to normal mask of two-tone transmittance.[1,2] A chromium (Cr)-based MTM (Typically top type) is being widely employed because of convenience of etch process caused by its only Cr-based structure consisted of Cr absorber layer and Cr half-tone layer. However, the top type of Cr-based MTM demands two Cr sputtering processes after each layer etching process and writing process. For this reason, a different material from the Cr-based MTM is required for reduction of mask fabrication time and cost. In this study, we evaluate a MTM which has a structure combined Cr with molybdenum silicide (MoSi) to resolve the issues mentioned above. The MoSi which is demonstrated by integrated circuit (IC) process is a suitable material for MTM evaluation. This structure could realize multi-transmittance in common with the Cr-based MTM. Moreover, it enables to reduce the number of sputtering process. We investigate a optimized structure upon consideration of productivity along with performance such as critical dimension (CD) variation and transmittance range of each structure. The transmittance is targeted at h-line wavelength (405 nm) in the evaluation. Compared with Cr-based MTM, the performances of all Cr-/MoSi-based MTMs are considered.

  15. Apparatus and method for generating partially coherent illumination for photolithography

    DOEpatents

    Sweatt, W.C.

    1999-07-06

    The present invention relates an apparatus and method for creating a bright, uniform source of partially coherent radiation for illuminating a pattern, in order to replicate an image of said pattern with a high degree of acuity. The present invention introduces a novel scatter plate into the optical path of source light used for illuminating a replicated object. The scatter plate has been designed to interrupt a focused, incoming light beam by introducing between about 8 to 24 diffraction zones blazed onto the surface of the scatter plate which intercept the light and redirect it to a like number of different positions in the condenser entrance pupil each of which is determined by the relative orientation and the spatial frequency of the diffraction grating in each of the several zones. Light falling onto the scatter plate, therefore, generates a plurality of unphased sources of illumination as seen by the back half of the optical system. The system includes a high brightness source, such as a laser, creating light which is taken up by a beam forming optic which focuses the incoming light into a condenser which in turn, focuses light into a field lens creating Kohler illumination image of the source in a camera entrance pupil. The light passing through the field lens illuminates a mask which interrupts the source light as either a positive or negative image of the object to be replicated. Light passing by the mask is focused into the entrance pupil of the lithographic camera creating an image of the mask onto a receptive media. 7 figs.

  16. Apparatus and method for generating partially coherent illumination for photolithography

    DOEpatents

    Sweatt, William C.

    1999-01-01

    The present invention relates an apparatus and method for creating a bright, uniform source of partially coherent radiation for illuminating a pattern, in order to replicate an image of said pattern with a high degree of acuity. The present invention introduces a novel scatter plate into the optical path of source light used for illuminating a replicated object. The scatter plate has been designed to interrupt a focused, incoming light beam by introducing between about 8 to 24 diffraction zones blazed onto the surface of the scatter plate which intercept the light and redirect it to a like number of different positions in the condenser entrance pupil each of which is determined by the relative orientation and the spatial frequency of the diffraction grating in each of the several zones. Light falling onto the scatter plate, therefore, generates a plurality of unphased sources of illumination as seen by the back half of the optical system. The system includes a high brightness source, such as a laser, creating light which is taken up by a beam forming optic which focuses the incoming light into a condenser which in turn, focuses light into a field lens creating Kohler illumination image of the source in a camera entrance pupil. The light passing through the field lens illuminates a mask which interrupts the source light as either a positive or negative image of the object to be replicated. Light passing by the mask is focused into the entrance pupil of the lithographic camera creating an image of the mask onto a receptive media.

  17. A Rotating Scatter Mask for Inexpensive Gamma-Ray Imaging in Orphan Source Search: Simulation Results

    NASA Astrophysics Data System (ADS)

    FitzGerald, Jack G. M.

    2015-02-01

    The Rotating Scatter Mask (RSM) system is an inexpensive retrofit that provides imaging capabilities to scintillating detectors. Unlike traditional collimator systems that primarily absorb photons in order to form an image, this system primarily scatters the photons. Over a single rotation, there is a unique, smooth response curve for each defined source position. Testing was conducted using MCNPX simulations. Image reconstruction was performed using a chi-squared reconstruction technique. A simulated 100 uCi, Cs-137 source at 10 meters was detected after a single, 50-second rotation when a uniform terrestrial background was present. A Cs-137 extended source was also tested. The RSM field-of-view is 360 degrees azimuthally as well as 54 degrees above and 54 degrees below the horizontal plane. Since the RSM is built from polyethylene, the overall cost and weight of the system is low. The system was designed to search for lost or stolen radioactive material, also known as the orphan source problem.

  18. Design of wavefront coding optical system with annular aperture

    NASA Astrophysics Data System (ADS)

    Chen, Xinhua; Zhou, Jiankang; Shen, Weimin

    2016-10-01

    Wavefront coding can extend the depth of field of traditional optical system by inserting a phase mask into the pupil plane. In this paper, the point spread function (PSF) of wavefront coding system with annular aperture are analyzed. Stationary phase method and fast Fourier transform (FFT) method are used to compute the diffraction integral respectively. The OTF invariance is analyzed for the annular aperture with cubic phase mask under different obscuration ratio. With these analysis results, a wavefront coding system using Maksutov-Cassegrain configuration is designed finally. It is an F/8.21 catadioptric system with annular aperture, and its focal length is 821mm. The strength of the cubic phase mask is optimized with user-defined operand in Zemax. The Wiener filtering algorithm is used to restore the images and the numerical simulation proves the validity of the design.

  19. SU-E-T-65: A Prospective Trial of Open Face Masks for Head and Neck Radiotherapy

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

    Wiant, D; Squire, S; Maurer, J

    Purpose: Open face head and neck masks allow for active patient monitoring during treatment and may reduced claustrophobia and anxiety compared to closed masks. The ability of open masks to limit intrafraction motion and to preserve the patient shape/position from simulation over protracted treatments should be considered. Methods: Thirty-two head and neck patients were prospectively randomized to treatment in a closed mask or a novel open face mask. All patients received daily volumetric imaging. The daily images were automatically rigidly registered to the planning CT’s offline using a commercial image processing tool. The shifts needed to optimize the registration, themore » mutual information coefficient (MI), and the Pearson correlation (PC) coefficients were recorded to evaluate shape preservation. The open group was set-up and monitored with surface imaging at treatment. The real time surface imaging information was recorded to evaluate intrafraction motion. Results: Sixteen patients were included in each group. Evaluations were made over a total of 984 fractions. The mean MI and PC showed significantly higher shape preservation for the open group than for the closed group (p = 0). The mean rotations for the open group were smaller or < 0.15° larger versus the closed group. The mean intrafraction motion for the open group was 0.93 +/−0.99 mm (2 SD). The maximum single fraction displacement was 3.2 mm. Fourteen of 16 patients showed no significant correlation of motion with fraction number (p > 0.05). Conclusion: The open masks preserved shape as well as the closed masks, and they limited motion to < 2 mm for 95% of the treated fractions. These results are consistent over treatment courses of up to 35 fractions. The open mask is suitable for treatment with or without active monitoring. This work was partially supported by Qfix.« less

  20. Utilization of optical emission endpoint in photomask dry etch processing

    NASA Astrophysics Data System (ADS)

    Faure, Thomas B.; Huynh, Cuc; Lercel, Michael J.; Smith, Adam; Wagner, Thomas

    2002-03-01

    Use of accurate and repeatable endpoint detection during dry etch processing of photomask is very important for obtaining good mask mean-to-target and CD uniformity performance. It was found that the typical laser reflectivity endpoint detecting system used on photomask dry etch systems had several key limitations that caused unnecessary scrap and non-optimum image size performance. Consequently, work to develop and implement use of a more robust optical emission endpoint detection system for chrome dry etch processing of photomask was performed. Initial feasibility studies showed that the emission technique was sensitive enough to monitor pattern loadings on contact and via level masks down to 3 percent pattern coverage. Additional work was performed to further improve this to 1 percent pattern coverage by optimizing the endpoint detection parameters. Comparison studies of mask mean-to-target performance and CD uniformity were performed with the use of optical emission endpoint versus laser endpoint for masks built using TOK IP3600 and ZEP 7000 resist systems. It was found that an improvement in mean-to-target performance and CD uniformity was realized on several types of production masks. In addition, part-to-part endpoint time repeatability was found to be significantly improved with the use of optical emission endpoint.

  1. Masking release for words in amplitude-modulated noise as a function of modulation rate and task

    PubMed Central

    Buss, Emily; Whittle, Lisa N.; Grose, John H.; Hall, Joseph W.

    2009-01-01

    For normal-hearing listeners, masked speech recognition can improve with the introduction of masker amplitude modulation. The present experiments tested the hypothesis that this masking release is due in part to an interaction between the temporal distribution of cues necessary to perform the task and the probability of those cues temporally coinciding with masker modulation minima. Stimuli were monosyllabic words masked by speech-shaped noise, and masker modulation was introduced via multiplication with a raised sinusoid of 2.5–40 Hz. Tasks included detection, three-alternative forced-choice identification, and open-set identification. Overall, there was more masking release associated with the closed than the open-set tasks. The best rate of modulation also differed as a function of task; whereas low modulation rates were associated with best performance for the detection and three-alternative identification tasks, performance improved with modulation rate in the open-set task. This task-by-rate interaction was also observed when amplitude-modulated speech was presented in a steady masker, and for low- and high-pass filtered speech presented in modulated noise. These results were interpreted as showing that the optimal rate of amplitude modulation depends on the temporal distribution of speech cues and the information required to perform a particular task. PMID:19603883

  2. Modeling of intense pulsed ion beam heated masked targets for extreme materials characterization

    DOE PAGES

    Barnard, John J.; Schenkel, Thomas

    2017-11-15

    Intense, pulsed ion beams locally heat materials and deliver dense electronic excitations that can induce material modifications and phase transitions. Material properties can potentially be stabilized by rapid quenching. Pulsed ion beams with pulse lengths of order ns have recently become available for materials processing. Here, we optimize mask geometries for local modification of materials by intense ion pulses. The goal is to rapidly excite targets volumetrically to the point where a phase transition or local lattice reconstruction is induced followed by rapid cooling that stabilizes desired material's properties fast enough before the target is altered or damaged by, e.g.,more » hydrodynamic expansion. By using a mask, the longitudinal dimension can be large compared to the transverse dimension, allowing the possibility of rapid transverse cooling. We performed HYDRA simulations that calculate peak temperatures for a series of excitation conditions and cooling rates of silicon targets with micro-structured masks and compare these to a simple analytical model. In conclusion, the model gives scaling laws that can guide the design of targets over a wide range of pulsed ion beam parameters.« less

  3. Modeling of intense pulsed ion beam heated masked targets for extreme materials characterization

    NASA Astrophysics Data System (ADS)

    Barnard, John J.; Schenkel, Thomas

    2017-11-01

    Intense, pulsed ion beams locally heat materials and deliver dense electronic excitations that can induce material modifications and phase transitions. Material properties can potentially be stabilized by rapid quenching. Pulsed ion beams with pulse lengths of order ns have recently become available for materials processing. Here, we optimize mask geometries for local modification of materials by intense ion pulses. The goal is to rapidly excite targets volumetrically to the point where a phase transition or local lattice reconstruction is induced followed by rapid cooling that stabilizes desired material's properties fast enough before the target is altered or damaged by, e.g., hydrodynamic expansion. By using a mask, the longitudinal dimension can be large compared to the transverse dimension, allowing the possibility of rapid transverse cooling. We performed HYDRA simulations that calculate peak temperatures for a series of excitation conditions and cooling rates of silicon targets with micro-structured masks and compare these to a simple analytical model. The model gives scaling laws that can guide the design of targets over a wide range of pulsed ion beam parameters.

  4. A Self-Aligned a-IGZO Thin-Film Transistor Using a New Two-Photo-Mask Process with a Continuous Etching Scheme.

    PubMed

    Fan, Ching-Lin; Shang, Ming-Chi; Li, Bo-Jyun; Lin, Yu-Zuo; Wang, Shea-Jue; Lee, Win-Der

    2014-08-11

    Minimizing the parasitic capacitance and the number of photo-masks can improve operational speed and reduce fabrication costs. Therefore, in this study, a new two-photo-mask process is proposed that exhibits a self-aligned structure without an etching-stop layer. Combining the backside-ultraviolet (BUV) exposure and backside-lift-off (BLO) schemes can not only prevent the damage when etching the source/drain (S/D) electrodes but also reduce the number of photo-masks required during fabrication and minimize the parasitic capacitance with the decreasing of gate overlap length at same time. Compared with traditional fabrication processes, the proposed process yields that thin-film transistors (TFTs) exhibit comparable field-effect mobility (9.5 cm²/V·s), threshold voltage (3.39 V), and subthreshold swing (0.3 V/decade). The delay time of an inverter fabricated using the proposed process was considerably decreased.

  5. A Self-Aligned a-IGZO Thin-Film Transistor Using a New Two-Photo-Mask Process with a Continuous Etching Scheme

    PubMed Central

    Fan, Ching-Lin; Shang, Ming-Chi; Li, Bo-Jyun; Lin, Yu-Zuo; Wang, Shea-Jue; Lee, Win-Der

    2014-01-01

    Minimizing the parasitic capacitance and the number of photo-masks can improve operational speed and reduce fabrication costs. Therefore, in this study, a new two-photo-mask process is proposed that exhibits a self-aligned structure without an etching-stop layer. Combining the backside-ultraviolet (BUV) exposure and backside-lift-off (BLO) schemes can not only prevent the damage when etching the source/drain (S/D) electrodes but also reduce the number of photo-masks required during fabrication and minimize the parasitic capacitance with the decreasing of gate overlap length at same time. Compared with traditional fabrication processes, the proposed process yields that thin-film transistors (TFTs) exhibit comparable field-effect mobility (9.5 cm2/V·s), threshold voltage (3.39 V), and subthreshold swing (0.3 V/decade). The delay time of an inverter fabricated using the proposed process was considerably decreased. PMID:28788159

  6. Masking in three pinnipeds: underwater, low-frequency critical ratios.

    PubMed

    Southall, B L; Schusterman, R J; Kastak, D

    2000-09-01

    Behavioral techniques were used to determine underwater masked hearing thresholds for a northern elephant seal (Mirounga angustirostris), a harbor seal (Phoca vitulina), and a California sea lion (Zalophus californianus). Octave-band white noise maskers were centered at five test frequencies ranging from 200 to 2500 Hz; a slightly wider noise band was used for testing at 100 Hz. Critical ratios were calculated at one masking noise level for each test frequency. Above 200 Hz, critical ratios increased with frequency. This pattern is similar to that observed in most animals tested, and indicates that these pinnipeds lack specializations for detecting low-frequency tonal sounds in noise. However, the individual pinnipeds in this study, particularly the northern elephant seal, detected signals at relatively low signal-to-noise ratios. These results provide a means of estimating zones of auditory masking for pinnipeds exposed to anthropogenic noise sources.

  7. General imaging of advanced 3D mask objects based on the fully-vectorial extended Nijboer-Zernike (ENZ) theory

    NASA Astrophysics Data System (ADS)

    van Haver, Sven; Janssen, Olaf T. A.; Braat, Joseph J. M.; Janssen, Augustus J. E. M.; Urbach, H. Paul; Pereira, Silvania F.

    2008-03-01

    In this paper we introduce a new mask imaging algorithm that is based on the source point integration method (or Abbe method). The method presented here distinguishes itself from existing methods by exploiting the through-focus imaging feature of the Extended Nijboer-Zernike (ENZ) theory of diffraction. An introduction to ENZ-theory and its application in general imaging is provided after which we describe the mask imaging scheme that can be derived from it. The remainder of the paper is devoted to illustrating the advantages of the new method over existing methods (Hopkins-based). To this extent several simulation results are included that illustrate advantages arising from: the accurate incorporation of isolated structures, the rigorous treatment of the object (mask topography) and the fully vectorial through-focus image formation of the ENZ-based algorithm.

  8. Protection of extreme ultraviolet lithography masks. II. Showerhead flow mitigation of nanoscale particulate contamination [Protection of EUV lithography masks II: Showerhead flow mitigation of nanoscale particulate contamination

    DOE PAGES

    Klebanoff, Leonard E.; Torczynski, John R.; Geller, Anthony S.; ...

    2015-03-27

    An analysis is presented of a method to protect the reticle (mask) in an extreme ultraviolet (EUV) mask inspection tool using a showerhead plenum to provide a continuous flow of clean gas over the surface of a reticle. The reticle is suspended in an inverted fashion (face down) within a stage/holder that moves back and forth over the showerhead plenum as the reticle is inspected. It is essential that no particles of 10-nm diameter or larger be deposited on the reticle during inspection. Particles can originate from multiple sources in the system, and mask protection from each source is explicitlymore » analyzed. The showerhead plate has an internal plenum with a solid conical wall isolating the aperture. The upper and lower surfaces of the plate are thin flat sheets of porous-metal material. These porous sheets form the top and bottom showerheads that supply the region between the showerhead plate and the reticle and the region between the conical aperture and the Optics Zone box with continuous flows of clean gas. The model studies show that the top showerhead provides robust reticle protection from particles of 10-nm diameter or larger originating from the Reticle Zone and from plenum surfaces contaminated by exposure to the Reticle Zone. Protection is achieved with negligible effect on EUV transmission. Furthermore, the bottom showerhead efficiently protects the reticle from nanoscale particles originating from the Optics Zone.« less

  9. Method for ultrafast optical deflection enabling optical recording via serrated or graded light illumination

    DOEpatents

    Heebner, John E [Livermore, CA

    2009-09-08

    In one general embodiment, a method for deflecting an optical signal input into a waveguide is provided. In operation, an optical input signal is propagated through a waveguide. Additionally, an optical control signal is applied to a mask positioned relative to the waveguide such that the application of the optical control signal to the mask is used to influence the optical input signal propagating in the waveguide. Furthermore, the deflected optical input signal output from the waveguide is detected in parallel on an array of detectors. In another general embodiment, a beam deflecting structure is provided for deflecting an optical signal input into a waveguide, the structure comprising at least one wave guiding layer for guiding an optical input signal and at least one masking layer including a pattern configured to influence characteristics of a material of the guiding layer when an optical control signal is passed through the masking layer in a direction of the guiding layer. In another general embodiment, a system is provided including a waveguide, an attenuating mask positioned on the waveguide, and an optical control source positioned to propagate pulsed laser light towards the attenuating mask and the waveguide such that a pattern of the attenuating mask is applied to the waveguide and material properties of at least a portion of the waveguide are influenced.

  10. Supermassive Black Holes and Their Host Spheroids. I. Disassembling Galaxies

    NASA Astrophysics Data System (ADS)

    Savorgnan, G. A. D.; Graham, A. W.

    2016-01-01

    Several recent studies have performed galaxy decompositions to investigate correlations between the black hole mass and various properties of the host spheroid, but they have not converged on the same conclusions. This is because their models for the same galaxy were often significantly different and not consistent with each other in terms of fitted components. Using 3.6 μm Spitzer imagery, which is a superb tracer of the stellar mass (superior to the K band), we have performed state-of-the-art multicomponent decompositions for 66 galaxies with directly measured black hole masses. Our sample is the largest to date and, unlike previous studies, contains a large number (17) of spiral galaxies with low black hole masses. We paid careful attention to the image mosaicking, sky subtraction, and masking of contaminating sources. After a scrupulous inspection of the galaxy photometry (through isophotal analysis and unsharp masking) and—for the first time—2D kinematics, we were able to account for spheroids large-scale, intermediate-scale, and nuclear disks bars rings spiral arms halos extended or unresolved nuclear sources; and partially depleted cores. For each individual galaxy, we compared our best-fit model with previous studies, explained the discrepancies, and identified the optimal decomposition. Moreover, we have independently performed one-dimensional (1D) and two-dimensional (2D) decompositions and concluded that, at least when modeling large, nearby galaxies, 1D techniques have more advantages than 2D techniques. Finally, we developed a prescription to estimate the uncertainties on the 1D best-fit parameters for the 66 spheroids that takes into account systematic errors, unlike popular 2D codes that only consider statistical errors.

  11. SUPERMASSIVE BLACK HOLES AND THEIR HOST SPHEROIDS. I. DISASSEMBLING GALAXIES

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

    Savorgnan, G. A. D.; Graham, A. W., E-mail: gsavorgn@astro.swin.edu.au

    Several recent studies have performed galaxy decompositions to investigate correlations between the black hole mass and various properties of the host spheroid, but they have not converged on the same conclusions. This is because their models for the same galaxy were often significantly different and not consistent with each other in terms of fitted components. Using 3.6 μm Spitzer imagery, which is a superb tracer of the stellar mass (superior to the K band), we have performed state-of-the-art multicomponent decompositions for 66 galaxies with directly measured black hole masses. Our sample is the largest to date and, unlike previous studies, containsmore » a large number (17) of spiral galaxies with low black hole masses. We paid careful attention to the image mosaicking, sky subtraction, and masking of contaminating sources. After a scrupulous inspection of the galaxy photometry (through isophotal analysis and unsharp masking) and—for the first time—2D kinematics, we were able to account for spheroids; large-scale, intermediate-scale, and nuclear disks; bars; rings; spiral arms; halos; extended or unresolved nuclear sources; and partially depleted cores. For each individual galaxy, we compared our best-fit model with previous studies, explained the discrepancies, and identified the optimal decomposition. Moreover, we have independently performed one-dimensional (1D) and two-dimensional (2D) decompositions and concluded that, at least when modeling large, nearby galaxies, 1D techniques have more advantages than 2D techniques. Finally, we developed a prescription to estimate the uncertainties on the 1D best-fit parameters for the 66 spheroids that takes into account systematic errors, unlike popular 2D codes that only consider statistical errors.« less

  12. Experimental geometry for simultaneous beam characterization and sample imaging allowing for pink beam Fourier transform holography or coherent diffractive imaging

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

    Flewett, Samuel; Eisebitt, Stefan

    2011-02-20

    One consequence of the self-amplified stimulated emission process used to generate x rays in free electron lasers (FELs) is the intrinsic shot-to-shot variance in the wavelength and temporal coherence. In order to optimize the results from diffractive imaging experiments at FEL sources, it will be advantageous to acquire a means of collecting coherence and spectral information simultaneously with the diffraction pattern from the sample we wish to study. We present a holographic mask geometry, including a grating structure, which can be used to extract both temporal and spatial coherence information alongside the sample scatter from each individual FEL shot andmore » also allows for the real space reconstruction of the sample using either Fourier transform holography or iterative phase retrieval.« less

  13. Eye Safety in Dentistry and Associated Liability.

    PubMed

    Arsenault, Peter; Tayebi, Amad

    2016-01-01

    The first objective of this article is to expressan experimental-work-supported opinion ofits authors regarding the inadequacy of thepresent dental mask and regular eyewearcombination for protecting dental care practitioners. Its second objective is to suggestamending OSHA Standard 1910.133(a)(1) tomandate effective eye protection for dentalcare practitioners by requiring the use ofeffective means for closing the bottom gapsbetween the lower rims of the lenses of theprotective eyewear and the upper edge ofthe mask worn by the practitioner.The various types and sources of dentalpractice eye occupational hazards and thepossible entry routes of dental debris towarddental practitioners'eyes are discussed.Experimental work, confirming theinadequacy of the present dental mask andeyewear combination for protecting dentalcare practitioners, is presented.

  14. Printability Optimization For Fine Pitch Solder Bonding

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

    Kwon, Sang-Hyun; Lee, Chang-Woo; Yoo, Sehoon

    2011-01-17

    Effect of metal mask and pad design on solder printability was evaluated by DOE in this study. The process parameters were stencil thickness, squeegee angle, squeegee speed, mask separating speed, and pad angle of PCB. The main process parameters for printability were stencil thickness and squeegee angle. The response surface showed that maximum printability of 1005 chip was achieved at the stencil thickness of 0.12 mm while the maximum printability of 0603 and 0402 chip was obtained at the stencil thickness of 0.05 mm. The bonding strength of the MLCC chips was also directly related with the printability.

  15. Micro-Fabricated Perforated Polymer Devices for Long-Term Drug Delivery

    DTIC Science & Technology

    2011-02-24

    conventional manufacturing methods. We have used a biocompatible polymer ( polyimide ) to serve as a reservoir and photolithographically produced microholes for...RIE with ICP source was used to etch holes on polyimide surface. Biocompatible materials Ti, SiO2 and SiNx were studied as mask materials. Ti film...used to fabricate micro holes on the surface of polyimide tubes. Several materials have been used to form the etching mask, including titanium film

  16. Improvement in defect classification efficiency by grouping disposition for reticle inspection

    NASA Astrophysics Data System (ADS)

    Lai, Rick; Hsu, Luke T. H.; Chang, Peter; Ho, C. H.; Tsai, Frankie; Long, Garrett; Yu, Paul; Miller, John; Hsu, Vincent; Chen, Ellison

    2005-11-01

    As the lithography design rule of IC manufacturing continues to migrate toward more advanced technology nodes, the mask error enhancement factor (MEEF) increases and necessitates the use of aggressive OPC features. These aggressive OPC features pose challenges to reticle inspection due to high false detection, which is time-consuming for defect classification and impacts the throughput of mask manufacturing. Moreover, higher MEEF leads to stricter mask defect capture criteria so that new generation reticle inspection tool is equipped with better detection capability. Hence, mask process induced defects, which were once undetectable, are now detected and results in the increase of total defect count. Therefore, how to review and characterize reticle defects efficiently is becoming more significant. A new defect review system called ReviewSmart has been developed based on the concept of defect grouping disposition. The review system intelligently bins repeating or similar defects into defect groups and thus allows operators to review massive defects more efficiently. Compared to the conventional defect review method, ReviewSmart not only reduces defect classification time and human judgment error, but also eliminates desensitization that is formerly inevitable. In this study, we attempt to explore the most efficient use of ReviewSmart by evaluating various defect binning conditions. The optimal binning conditions are obtained and have been verified for fidelity qualification through inspection reports (IRs) of production masks. The experiment results help to achieve the best defect classification efficiency when using ReviewSmart in the mask manufacturing and development.

  17. The SomnuSeal Oral Mask Is Reasonably Tolerated by Otherwise CPAP Noncompliant Patients with OSA

    PubMed Central

    Katz, N.; Adir, Y.; Etzioni, T.; Kurtz, E.; Pillar, G.

    2013-01-01

    Compliance with CPAP is the major limiting factor in treating patients with OSA. The novel SomnuSeal mask is an oral self-adaptable mask located between the teeth and the lips ensuring that there are no air leaks or skin abrasions. Fifty patients with AHI > 20, who failed previous CPAP trials, were asked to sleep with the mask for one month. In all patients, the mask was connected to an AutoPAP machine with a heated humidifier. Efficacy, convenience, and compliance (average usage for 4 or more hours per night) were monitored. Fifty patients (41 m and 9 f, mean age 57 ± 12 years, BMI 33.6 ± 4.9 kg/m2, and AHI 47 ± 23/h) participated. Eleven were classified as compliant (average mask usage of 26 nights, 4.7 hours per night), five were only partially compliant (average usage of 13 nights, 2.9 hours per night), and 34 could not comply with it. In all patients who slept with it, the efficacy (assessed by residual AHI derived from the CPAP device) was good with an AHI of less than 8/hour. Interestingly, the required optimal pressure decreased from an average of 9.3 cmH2O to 4.6 cmH2O. The SomnuSeal oral interface is effective and may result in converting noncompliant untreated patients with OSA into well-treated ones. PMID:24228181

  18. Mobile geographic information system solution for pavement condition surveys [summary].

    DOT National Transportation Integrated Search

    2012-01-01

    The State Materials Office (SMO) of the Florida : Department of Transportation (FDOT) performs : annual Pavement Condition Surveys (PCS) of : the Departments extensive pavement network. : This work is performed by single-person crews in : inertial...

  19. Semiconducting Metal Oxide Based Sensors for Selective Gas Pollutant Detection

    PubMed Central

    Kanan, Sofian M.; El-Kadri, Oussama M.; Abu-Yousef, Imad A.; Kanan, Marsha C.

    2009-01-01

    A review of some papers published in the last fifty years that focus on the semiconducting metal oxide (SMO) based sensors for the selective and sensitive detection of various environmental pollutants is presented. PMID:22408500

  20. New strain states and radical property tuning of metal oxides using a nanocomposite thin film approach

    DOE PAGES

    MacManus-Driscoll, Judith; Suwardi, Ady; Kursumovic, Ahmed; ...

    2015-05-05

    Auxetic-like strain states were generated in self-assembled nanocomposite thin films of (Ba 0.6Sr 0.4TiO 3) 1–x – (Sm 2O 3) x(BSTO – SmO). A switch from auxetic-like to elastic-like strain behavior was observed for x > 0.50, when the SmO switched from being nanopillars in the BSTO matrix to being the matrix with BSTO nanopillars embedded in it. A simple model was adopted to explain how in-plane strain varies with x. At high x (0.75), strongly enhanced ferroelectric properties were obtained compared to pure BSTO films. Furthermore, the nanocomposite method represents a powerful new way to tune the properties ofmore » a wide range of strongly correlated metal oxides whose properties are very sensitive to strain.« less

  1. Janus Monolayer Transition-Metal Dichalcogenides.

    PubMed

    Zhang, Jing; Jia, Shuai; Kholmanov, Iskandar; Dong, Liang; Er, Dequan; Chen, Weibing; Guo, Hua; Jin, Zehua; Shenoy, Vivek B; Shi, Li; Lou, Jun

    2017-08-22

    The crystal configuration of sandwiched S-Mo-Se structure (Janus SMoSe) at the monolayer limit has been synthesized and carefully characterized in this work. By controlled sulfurization of monolayer MoSe 2 , the top layer of selenium atoms is substituted by sulfur atoms, while the bottom selenium layer remains intact. The structure of this material is systematically investigated by Raman, photoluminescence, transmission electron microscopy, and X-ray photoelectron spectroscopy and confirmed by time-of-flight secondary ion mass spectrometry. Density functional theory (DFT) calculations are performed to better understand the Raman vibration modes and electronic structures of the Janus SMoSe monolayer, which are found to correlate well with corresponding experimental results. Finally, high basal plane hydrogen evolution reaction activity is discovered for the Janus monolayer, and DFT calculation implies that the activity originates from the synergistic effect of the intrinsic defects and structural strain inherent in the Janus structure.

  2. Janus Monolayer Transition-Metal Dichalcogenides

    DOE PAGES

    Zhang, Jing; Jia, Shuai; Kholmanov, Iskandar; ...

    2017-08-03

    In this work, the crystal configuration of sandwiched S–Mo–Se structure (Janus SMoSe) at the monolayer limit has been synthesized and carefully characterized. By controlled sulfurization of monolayer MoSe 2, the top layer of selenium atoms is substituted by sulfur atoms, while the bottom selenium layer remains intact. Furthermore, the structure of this material is systematically investigated by Raman, photoluminescence, transmission electron microscopy, and X-ray photoelectron spectroscopy and confirmed by time-of-flight secondary ion mass spectrometry. Density functional theory (DFT) calculations are performed to better understand the Raman vibration modes and electronic structures of the Janus SMoSe monolayer, which are found tomore » correlate well with corresponding experimental results. Finally, high basal plane hydrogen evolution reaction activity is discovered for the Janus monolayer, and DFT calculation implies that the activity originates from the synergistic effect of the intrinsic defects and structural strain inherent in the Janus structure.« less

  3. Scanner qualification with IntenCD based reticle error correction

    NASA Astrophysics Data System (ADS)

    Elblinger, Yair; Finders, Jo; Demarteau, Marcel; Wismans, Onno; Minnaert Janssen, Ingrid; Duray, Frank; Ben Yishai, Michael; Mangan, Shmoolik; Cohen, Yaron; Parizat, Ziv; Attal, Shay; Polonsky, Netanel; Englard, Ilan

    2010-03-01

    Scanner introduction into the fab production environment is a challenging task. An efficient evaluation of scanner performance matrices during factory acceptance test (FAT) and later on during site acceptance test (SAT) is crucial for minimizing the cycle time for pre and post production-start activities. If done effectively, the matrices of base line performance established during the SAT are used as a reference for scanner performance and fleet matching monitoring and maintenance in the fab environment. Key elements which can influence the cycle time of the SAT, FAT and maintenance cycles are the imaging, process and mask characterizations involved with those cycles. Discrete mask measurement techniques are currently in use to create across-mask CDU maps. By subtracting these maps from their final wafer measurement CDU map counterparts, it is possible to assess the real scanner induced printed errors within certain limitations. The current discrete measurement methods are time consuming and some techniques also overlook mask based effects other than line width variations, such as transmission and phase variations, all of which influence the final printed CD variability. Applied Materials Aera2TM mask inspection tool with IntenCDTM technology can scan the mask at high speed, offer full mask coverage and accurate assessment of all masks induced source of errors simultaneously, making it beneficial for scanner qualifications and performance monitoring. In this paper we report on a study that was done to improve a scanner introduction and qualification process using the IntenCD application to map the mask induced CD non uniformity. We will present the results of six scanners in production and discuss the benefits of the new method.

  4. Towards hybrid pixel detectors for energy-dispersive or soft X-ray photon science

    PubMed Central

    Jungmann-Smith, J. H.; Bergamaschi, A.; Brückner, M.; Cartier, S.; Dinapoli, R.; Greiffenberg, D.; Huthwelker, T.; Maliakal, D.; Mayilyan, D.; Medjoubi, K.; Mezza, D.; Mozzanica, A.; Ramilli, M.; Ruder, Ch.; Schädler, L.; Schmitt, B.; Shi, X.; Tinti, G.

    2016-01-01

    JUNGFRAU (adJUstiNg Gain detector FoR the Aramis User station) is a two-dimensional hybrid pixel detector for photon science applications at free-electron lasers and synchrotron light sources. The JUNGFRAU 0.4 prototype presented here is specifically geared towards low-noise performance and hence soft X-ray detection. The design, geometry and readout architecture of JUNGFRAU 0.4 correspond to those of other JUNGFRAU pixel detectors, which are charge-integrating detectors with 75 µm × 75 µm pixels. Main characteristics of JUNGFRAU 0.4 are its fixed gain and r.m.s. noise of as low as 27 e− electronic noise charge (<100 eV) with no active cooling. The 48 × 48 pixels JUNGFRAU 0.4 prototype can be combined with a charge-sharing suppression mask directly placed on the sensor, which keeps photons from hitting the charge-sharing regions of the pixels. The mask consists of a 150 µm tungsten sheet, in which 28 µm-diameter holes are laser-drilled. The mask is aligned with the pixels. The noise and gain characterization, and single-photon detection as low as 1.2 keV are shown. The performance of JUNGFRAU 0.4 without the mask and also in the charge-sharing suppression configuration (with the mask, with a ‘software mask’ or a ‘cluster finding’ algorithm) is tested, compared and evaluated, in particular with respect to the removal of the charge-sharing contribution in the spectra, the detection efficiency and the photon rate capability. Energy-dispersive and imaging experiments with fluorescence X-ray irradiation from an X-ray tube and a synchrotron light source are successfully demonstrated with an r.m.s. energy resolution of 20% (no mask) and 14% (with the mask) at 1.2 keV and of 5% at 13.3 keV. The performance evaluation of the JUNGFRAU 0.4 prototype suggests that this detection system could be the starting point for a future detector development effort for either applications in the soft X-ray energy regime or for an energy-dispersive detection system. PMID:26917124

  5. Single image super-resolution using self-optimizing mask via fractional-order gradient interpolation and reconstruction.

    PubMed

    Yang, Qi; Zhang, Yanzhu; Zhao, Tiebiao; Chen, YangQuan

    2017-04-04

    Image super-resolution using self-optimizing mask via fractional-order gradient interpolation and reconstruction aims to recover detailed information from low-resolution images and reconstruct them into high-resolution images. Due to the limited amount of data and information retrieved from low-resolution images, it is difficult to restore clear, artifact-free images, while still preserving enough structure of the image such as the texture. This paper presents a new single image super-resolution method which is based on adaptive fractional-order gradient interpolation and reconstruction. The interpolated image gradient via optimal fractional-order gradient is first constructed according to the image similarity and afterwards the minimum energy function is employed to reconstruct the final high-resolution image. Fractional-order gradient based interpolation methods provide an additional degree of freedom which helps optimize the implementation quality due to the fact that an extra free parameter α-order is being used. The proposed method is able to produce a rich texture detail while still being able to maintain structural similarity even under large zoom conditions. Experimental results show that the proposed method performs better than current single image super-resolution techniques. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  6. Designing to win in sub-90nm mask production

    NASA Astrophysics Data System (ADS)

    Zhang, Yuan

    2005-11-01

    An informal survey conducted with key customers by Photronics indicates that the time gap between technology nodes has accelerated in recent years. Previously the cycle was three years. However, between 130nm and 90nm there was less than a 2 year gap, and between 90nm and 65nm a 1.5 year gap exists. As a result, the technical challenges have increased substantially. In addition, mask costs are rising exponentially due to high capital equipment cost, a shrinking customer base, long write times and increased applications of 193nm EAPSM or AAPSM. Collaboration among EDA companies, mask houses and wafer manufacturers is now more important than ever. This paper will explore avenues for reducing mask costs, mainly in the areas of: write-time reduction through design for manufacturing (DFM), and yield improvement through specification relaxation. Our study conducted through layout vertex modeling suggests that a simple design shape such as a square versus a circle or an angled structure helps reduce shot count and write time. Shot count reduction through mask layout optimization, and advancement in new generation E-beam writers can reduce write time up to 65%. An advanced laser writer can produce those less critical E-beam layers in less than half the time of an e-beam writer. Additionally, the emerging imprint lithography brings new life and new challenges to the photomask industry with applications in many fields outside of the semiconductor industry. As immersion lithography is introduced for 45nm device production, polarization and MEEF effects due to the mask will become severe. Larger magnification not only provides benefits on CD control and MEEF, but also extends the life time of current 90nm/65nm tool sets where 45nm mask sets can be produced at a lower cost.

  7. An in-vitro-in-vivo taste assessment of bitter drug: comparative electronic tongues study.

    PubMed

    Maniruzzaman, Mohammed; Douroumis, Dennis

    2015-01-01

    The efficiency of the Astree e-tongue and Taste Sensing system TS5000Z for the evaluation of the taste masking effect of hot melt extruded formulations was investigated in this study. Hot melt extrusion (HME) processing was optimized using Randcastle single screw extruder (USA) to manufacture extrudates with desirable characteristics. Cationic model drug propranolol HCl (PRP) was processed with the anionic polymers - Eudragit L100 (L100) and Eudragit L100-55 (Acryl-EZE). Solid state of the drug in polymer matrices was evaluated by scanning electron microscopy (SEM), differential scanning calorimetry, particle size analysis, Fourier transform infrared (FTIR) and Nuclear magnetic resonance (NMR) analysis. In-vitro taste masking efficiency of the two polymers was performed by using two different e-tongues (Astree e-tongue and TS5000Z). The results obtained from both e-tongues were further compared and contrast to find out the sensor outputs in all formulations. Solid state analysis of the extruded formulations revealed the presence of amorphous PRP. Both e-tongues were able to detect the taste masking variations of the extrudates and were in good agreement with the in-vivo results obtained from a panel of six healthy human volunteers (R(2)  > 0.84). However, each e-tongue sensor demonstrated different sensitivity, suggesting a careful consideration of the experimental findings during melt extrusion, is necessary for the development of taste-masked formulations. Furthermore, FTIR spectroscopy and NMR studies revealed possible drug polymer intermolecular interactions as the mechanism of successful taste masking. HME can effectively be used to manufacture taste-masked extruded formulations, while both e-tongues demonstrated satisfactory taste analysis for the development of taste-masked formulations. © 2014 Royal Pharmaceutical Society.

  8. Spectral Topography Generation for Arbitrary Grids

    NASA Astrophysics Data System (ADS)

    Oh, T. J.

    2015-12-01

    A new topography generation tool utilizing spectral transformation technique for both structured and unstructured grids is presented. For the source global digital elevation data, the NASA Shuttle Radar Topography Mission (SRTM) 15 arc-second dataset (gap-filling by Jonathan de Ferranti) is used and for land/water mask source, the NASA Moderate Resolution Imaging Spectroradiometer (MODIS) 30 arc-second land water mask dataset v5 is used. The original source data is coarsened to a intermediate global 2 minute lat-lon mesh. Then, spectral transformation to the wave space and inverse transformation with wavenumber truncation is performed for isotropic topography smoothness control. Target grid topography mapping is done by bivariate cubic spline interpolation from the truncated 2 minute lat-lon topography. Gibbs phenomenon in the water region can be removed by overwriting ocean masked target coordinate grids with interpolated values from the intermediate 2 minute grid. Finally, a weak smoothing operator is applied on the target grid to minimize the land/water surface height discontinuity that might have been introduced by the Gibbs oscillation removal procedure. Overall, the new topography generation approach provides spectrally-derived, smooth topography with isotropic resolution and minimum damping, enabling realistic topography forcing in the numerical model. Topography is generated for the cubed-sphere grid and tested on the KIAPS Integrated Model (KIM).

  9. Poisson-Spot Intensity Reduction with a Partially-Transparent Petal-Shaped Optical Mask

    NASA Technical Reports Server (NTRS)

    Shiri, Shahram; Wasylkiwskyj, Wasyl

    2013-01-01

    The presence of Poisson's spot, also known as the spot of Arago, formed along the optical axis in the geometrical shadow behind an obstruction, has been known since the 18th century. The presence of this spot can best be described as the consequence of constructive interference of light waves diffracted on the edge of the obstruction where its central position can··be determined by the symmetry of the object More recently, the elimination of this spot has received attention in the fields of particle physics, high-energy lasers, astronomy and lithography. In this paper, we introduce a novel, partially transparent petaled mask shape that suppresses the bright spot by up to 10 orders of magnitude in intensity, with powerful applications to many of the above fields. The optimization technique formulated in this design can identify mask shapes having partial transparency only near the petal tips.

  10. Micropellets coated with Kollicoat® Smartseal 30D for taste masking in liquid oral dosage forms.

    PubMed

    Dashevskiy, Andriy; Mohylyuk, Valentyn; Ahmed, Abid Riaz; Kolter, Karl; Guth, Felicitas; Bodmeier, Roland

    2017-09-01

    The objective of this study was to develop delivery systems for taste masking based on multiparticulates coated with Kollicoat ® Smartseal 30D formulated as liquid oral suspensions. Coating of particles containing bitter drugs with Kollicoat ® Smartseal reduced drug leaching into aqueous medium, especially when increasing pH, therefore can be used for the formulation of liquid dosage forms. Application of an intermediate layer of ion exchange resins between drug layer and coating can further decrease drug leaching into aqueous vehicle that is beneficial in terms of taste masking. Using optimized compositions of liquid vehicles such as addition of sugar alcohols and ion exchange resin, reconstitutable or ready-to-use liquid dosage forms with micropellets can be developed with bitter taste protection after redispersion lasting longer than 3 weeks, which exceeds the usual period of application.

  11. Extreme ultraviolet patterned mask inspection performance of advanced projection electron microscope system for 11nm half-pitch generation

    NASA Astrophysics Data System (ADS)

    Hirano, Ryoichi; Iida, Susumu; Amano, Tsuyoshi; Watanabe, Hidehiro; Hatakeyama, Masahiro; Murakami, Takeshi; Suematsu, Kenichi; Terao, Kenji

    2016-03-01

    Novel projection electron microscope optics have been developed and integrated into a new inspection system named EBEYE-V30 ("Model EBEYE" is an EBARA's model code) , and the resulting system shows promise for application to half-pitch (hp) 16-nm node extreme ultraviolet lithography (EUVL) patterned mask inspection. To improve the system's inspection throughput for 11-nm hp generation defect detection, a new electron-sensitive area image sensor with a high-speed data processing unit, a bright and stable electron source, and an image capture area deflector that operates simultaneously with the mask scanning motion have been developed. A learning system has been used for the mask inspection tool to meet the requirements of hp 11-nm node EUV patterned mask inspection. Defects are identified by the projection electron microscope system using the "defectivity" from the characteristics of the acquired image. The learning system has been developed to reduce the labor and costs associated with adjustment of the detection capability to cope with newly-defined mask defects. We describe the integration of the developed elements into the inspection tool and the verification of the designed specification. We have also verified the effectiveness of the learning system, which shows enhanced detection capability for the hp 11-nm node.

  12. A combined spectroscopic and plasma chemical kinetic analysis of ionospheric samarium releases

    NASA Astrophysics Data System (ADS)

    Holmes, Jeffrey M.; Dressler, Rainer A.; Pedersen, Todd R.; Caton, Ronald G.; Miller, Daniel

    2017-05-01

    Two rocket-borne releases of samarium vapor in the upper atmosphere occurred in May 2013, as part of the Metal Oxide Space Clouds experiment. The releases were characterized by a combination of optical and RF diagnostic instruments located at the Roi-Namur launch site and surrounding islands and atolls. The evolution of the optical spectrum of the solar-illuminated cloud was recorded with a spectrograph covering a 400-800 nm spectral range. The spectra exhibit two distinct spectral regions centered at 496 and 636 nm within which the relative intensities change insignificantly. The ratio between the integrated intensities within these regions, however, changes with time, suggesting that they are associated with different species. With the help of an equilibrium plasma spectral model we attribute the region centered at 496 nm to neutral samarium atoms (Sm I radiance) and features peaking at 649 nm to a molecular species. No evidence for structure due to Sm+ (Sm II) is identified. The persistence of the Sm I radiance suggests a high dissociative recombination rate for the chemi-ionization product, SmO+. A one-dimensional plasma chemical kinetic model of the evolution of the density ratio NSmO/NSm(t) demonstrates that the molecular feature peaking at 649 nm can be attributed to SmO radiance. SmO+ radiance is not identified. By adjusting the Sm vapor mass of the chemical kinetic model input to match the evolution of the total electron density determined by ionosonde data, we conclude that less than 5% of the payload samarium was vaporized.

  13. Conditional loss of hepatocellular Hedgehog signaling in female mice leads to the persistence of hepatic steroidogenesis, androgenization and infertility.

    PubMed

    Rennert, Christiane; Eplinius, Franziska; Hofmann, Ute; Johänning, Janina; Rolfs, Franziska; Schmidt-Heck, Wolfgang; Guthke, Reinhardt; Gebhardt, Rolf; Ricken, Albert M; Matz-Soja, Madlen

    2017-11-01

    The Hedgehog signaling pathway is known to be involved in embryogenesis, tissue remodeling, and carcinogenesis. Because of its involvement in carcinogenesis, it seems an interesting target for cancer therapy. Indeed, Sonidegib, an approved inhibitor of the Hedgehog receptor Smoothened (Smo), is highly active against diverse carcinomas, but its use is also reported to be associated with several systemic side effects. Our former work in adult mice demonstrated hepatic Hedgehog signaling to play a key role in the insulin-like growth factor axis and lipid metabolism. The current work using mice with an embryonic and hepatocyte-specific Smo deletion describes an adverse impact of the hepatic Hedgehog pathway on female fertility. In female SAC-KO mice, we detected androgenization characterized by a 3.3-fold increase in testosterone at 12 weeks of age based on an impressive induction of steroidogenic gene expression in hepatocytes, but not in the classic steroidogenic organs (ovary and adrenal gland). Along with the elevated level of testosterone, the female SAC-KO mice showed infertility characterized by juvenile reproductive organs and acyclicity. The endocrine and reproductive alterations resembled polycystic ovarian syndrome and could be confirmed in a second mouse model with conditional deletion of Smo at 8 weeks of age after an extended period of 8 months. We conclude that the down-regulation of hepatic Hedgehog signaling leads to an impaired hormonal balance by the induction of steroidogenesis in the liver. These effects of Hedgehog signaling inhibition should be considered when using Hedgehog inhibitors as anti-cancer drugs.

  14. Fiber Bragg grating fabrication for the implementation of sensors in the electronics and optoelectronics laboratory at BUAP

    NASA Astrophysics Data System (ADS)

    Bracamontes Rodríguez, Y. E.; Beltrán Pérez, G.; Castillo Mixcóatl, J.; Muñoz Aguirre, S.

    2011-09-01

    Fiber Bragg gratings (FBG) are important optical devices since they have been quite successful not only in the field of communications but also in sensor systems and optical fiber lasers. In the sensors area they are generally used as detection elements for different physical parameters such as temperature, strain, flow, etc. In the electronics and optoelectronics laboratory at Benemérita Universidad Autónoma de Puebla (LEyO-BUAP), there are already experimental setups of sensors as well as laser systems, where FBGs are fundamental elements for their adequate performance. However, these FBGs are commercial devices and they present limited characteristics in their transmission profiles, bandwidth and reflectivity. On the other hand, in some occasions, the delivery time from the fabricant to the customer is quite long. Therefore, it is important for LEyO to implement a system to fabricate this kind of devices, which would mean LEyO independence in the technological development. In this work, results of FBGs fabrication based on the phase mask technique are presented. Such mask is optimized for UV and it has a period of 1060 nm. A Nd:YAG pulsed laser with a 5 ns pulse length and an energy of 40 mJ was used as the UV source employing the 4th harmonic generation to obtain a 266 nm wavelength. Ge-doped fiber was used to fabricate the devices.

  15. Active galactic nucleus and quasar science with aperture masking interferometry on the James Webb Space Telescope

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

    Ford, K. E. Saavik; McKernan, Barry; Sivaramakrishnan, Anand

    Due to feedback from accretion onto supermassive black holes (SMBHs), active galactic nuclei (AGNs) are believed to play a key role in ΛCDM cosmology and galaxy formation. However, AGNs extreme luminosities and the small angular size of their accretion flows create a challenging imaging problem. We show that the James Webb Space Telescope's Near Infrared Imager and Slitless Spectrograph (JWST-NIRISS) Aperture Masking Interferometry (AMI) mode will enable true imaging (i.e., without any requirement of prior assumptions on source geometry) at ∼65 mas angular resolution at the centers of AGNs. This is advantageous for studying complex extended accretion flows around SMBHsmore » and in other areas of angular-resolution-limited astrophysics. By simulating data sequences incorporating expected sources of noise, we demonstrate that JWST-NIRISS AMI mode can map extended structure at a pixel-to-pixel contrast of ∼10{sup –2} around an L = 7.5 point source, using short exposure times (minutes). Such images will test models of AGN feedback, fueling, and structure (complementary with ALMA observations), and are not currently supported by any ground-based IR interferometer or telescope. Binary point source contrast with NIRISS is ∼10{sup –4} (for observing binary nuclei in merging galaxies), significantly better than current ground-based optical or IR interferometry. JWST-NIRISS's seven-hole non-redundant mask has a throughput of 15%, and utilizes NIRISS's F277W (2.77 μm), F380M (3.8 μm), F430M (4.3 μm), and F480M (4.8 μm) filters. NIRISS's square pixels are 65 mas per side, with a field of view ∼2' × 2'. We also extrapolate our results to AGN science enabled by non-redundant masking on future 2.4 m and 16 m space telescopes working at long-UV to near-IR wavelengths.« less

  16. Coastal hazards in a changing world: projecting and communicating future coastal flood risk at the local-scale using the Coastal Storm Modeling System (CoSMoS)

    NASA Astrophysics Data System (ADS)

    O'Neill, Andrea; Barnard, Patrick; Erikson, Li; Foxgrover, Amy; Limber, Patrick; Vitousek, Sean; Fitzgibbon, Michael; Wood, Nathan

    2017-04-01

    The risk of coastal flooding will increase for many low-lying coastal regions as predominant contributions to flooding, including sea level, storm surge, wave setup, and storm-related fluvial discharge, are altered with climate change. Community leaders and local governments therefore look to science to provide insight into how climate change may affect their areas. Many studies of future coastal flooding vulnerability consider sea level and tides, but ignore other important factors that elevate flood levels during storm events, such as waves, surge, and discharge. Here we present a modelling approach that considers a broad range of relevant processes contributing to elevated storm water levels for open coast and embayment settings along the U.S. West Coast. Additionally, we present online tools for communicating community-relevant projected vulnerabilities. The Coastal Storm Modeling System (CoSMoS) is a numerical modeling system developed to predict coastal flooding due to both sea-level rise (SLR) and plausible 21st century storms for active-margin settings like the U.S. West Coast. CoSMoS applies a predominantly deterministic framework of multi-scale models encompassing large geographic scales (100s to 1000s of kilometers) to small-scale features (10s to 1000s of meters), resulting in flood extents that can be projected at a local resolution (2 meters). In the latest iteration of CoSMoS applied to Southern California, U.S., efforts were made to incorporate water level fluctuations in response to regional storm impacts, locally wind-generated waves, coastal river discharge, and decadal-scale shoreline and cliff changes. Coastal hazard projections are available in a user-friendly web-based tool (www.prbo.org/ocof), where users can view variations in flood extent, maximum flood depth, current speeds, and wave heights in response to a range of potential SLR and storm combinations, providing direct support to adaptation and management decisions. In order to capture the societal aspect of the hazard, projections are combined with socioeconomic exposure to produce clear, actionable information (https://www.usgs.gov/apps/hera/); this integrated approach to hazard displays provides an example of how to effectively translate complex climate impacts projections into simple, societally-relevant information.

  17. The role of RT carry-over for congruence sequence effects in masked priming.

    PubMed

    Huber-Huber, Christoph; Ansorge, Ulrich

    2017-05-01

    The present study disentangles 2 sources of the congruence sequence effect with masked primes: congruence and response time of the previous trial (reaction time [RT] carry-over). Using arrows as primes and targets and a metacontrast masking procedure we found congruence as well as congruence sequence effects. In addition, congruence sequence effects decreased when RT carry-over was accounted for in a mixed model analysis, suggesting that RT carry-over contributes to congruence sequence effects in masked priming. Crucially, effects of previous trial congruence were not cancelled out completely indicating that RT carry-over and previous trial congruence are 2 sources feeding into the congruence sequence effect. A secondary task requiring response speed judgments demonstrated general awareness of response speed (Experiments 1), but removing this secondary task (Experiment 2) showed that RT carry-over effects were also present in single-task conditions. During (dual-task) prime-awareness test parts of both experiments, however, RT carry-over failed to modulate congruence effects, suggesting that some task sets of the participants can prevent the effect. The basic RT carry-over effects are consistent with the conflict adaptation account, with the adaptation to the statistics of the environment (ASE) model, and possibly with the temporal learning explanation. Additionally considering the task-dependence of RT carry-over, the results are most compatible with the conflict adaptation account. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  18. SHIELD: FITGALAXY -- A Software Package for Automatic Aperture Photometry of Extended Sources

    NASA Astrophysics Data System (ADS)

    Marshall, Melissa

    2013-01-01

    Determining the parameters of extended sources, such as galaxies, is a common but time-consuming task. Finding a photometric aperture that encompasses the majority of the flux of a source and identifying and excluding contaminating objects is often done by hand - a lengthy and difficult to reproduce process. To make extracting information from large data sets both quick and repeatable, I have developed a program called FITGALAXY, written in IDL. This program uses minimal user input to automatically fit an aperture to, and perform aperture and surface photometry on, an extended source. FITGALAXY also automatically traces the outlines of surface brightness thresholds and creates surface brightness profiles, which can then be used to determine the radial properties of a source. Finally, the program performs automatic masking of contaminating sources. Masks and apertures can be applied to multiple images (regardless of the WCS solution or plate scale) in order to accurately measure the same source at different wavelengths. I present the fluxes, as measured by the program, of a selection of galaxies from the Local Volume Legacy Survey. I then compare these results with the fluxes given by Dale et al. (2009) in order to assess the accuracy of FITGALAXY.

  19. Thermal Neutron Point Source Imaging using a Rotating Modulation Collimator (RMC)

    DTIC Science & Technology

    2010-03-01

    Source Details.........................................................................................37 3.5 Simulation of RMC in MCNP ...passed through the masks at each rotation angle. ................................. 42 19. Figure 19: MCNP Generate Modulation Profile for Cadmium. The...Cadmium. The multi-energetic neutron source simulation from MCNP is used for this plot. The energy is values are shown per energy bin. The

  20. Monitoring of bacterial pathogens at workplaces in power plant using biochemical and molecular methods.

    PubMed

    Ławniczek-Wałczyk, Anna; Gołofit-Szymczak, Małgorzata; Cyprowski, Marcin; Stobnicka, Agata; Górny, Rafał L

    2017-04-01

    The aim of this study was to characterize the ways of spreading of the most common bacterial species isolated from workers as well as from the air and raw materials at the workplaces in power plant utilizing biomass sources. To monitor microbial transmission and identify the source of contamination in the working environment, a combination of molecular and biochemical methods was applied. The study was carried out at workplaces in power plant utilizes biomass as a main fuel source. At each of the studied workplaces, bioaerosol particles were collected on sterile Teflon filters using personal conical inhalable samplers (CIS), and biomass samples (straw pellets and briquettes, corn briquettes, sunflower pellets and wood chips) were directly taken from their storage places. Simultaneously with that, the swab samples from the hands of ten workers and their used respiratory masks (of FFP2 class) were also collected after the work shift to evaluate individual workers' microbial contamination. In all collected samples, total bacterial concentrations were assessed and the most common microbial isolates were identified to the species level using both biochemical (API tests) and molecular polymerase chain reaction (PCR), followed by random amplification of polymorphic DNA (RAPD) typing methods. The mean concentrations of culturable bacteria in the air and in biomass samples at the studied workplaces were high, i.e. 1.2 × 10 6 cfu/m 3 and 3.8 × 10 4 cfu/g, respectively. The number of bacteria in the swab and mask samples also reached a high level of 1.4 × 10 4 cfu/ml and 1.9 × 10 3 cfu/cm 2 , respectively. Among the most frequently isolated microorganisms from all types of samples were Gram-positive bacteria of the genus Bacillus and Staphylococcus xylosus. 37 bacterial strains belonging to the genus Bacillus (B. licheniformis 8, B. pumilus 15 and B. subtilis 4) and Staphylococcus (10) were genotyped by the RAPD-PCR method. Based on RAPD-PCR analyses, the genomic similarity among 19 Bacillus strains isolated from biomass, air, protective mask and hand samples as well as 6 S. xylosus strains isolated from air, mask and hand samples exceeded 80%. This study demonstrated that biomass is the primary source of bacteria at power plant workplaces. These results also revealed that biomass-associated bacteria can be easily transferred to workers' hands and mask during their routine activities. To improve health protection at the workplaces, adequate training courses on hand hygiene and how to use and remove respiratory masks correctly for workers should be introduced as a key element of the prevention strategy. From the occupational point of view, the PCR-based methods seem to be an efficient tool for a fast and precise typing of bacterial strains isolated from different sources in the occupational environment. Such methods may help to implement appropriate prophylactic procedures and minimize transmission of infectious agents at workplaces.

  1. Method of plasma etching Ga-based compound semiconductors

    DOEpatents

    Qiu, Weibin; Goddard, Lynford L.

    2012-12-25

    A method of plasma etching Ga-based compound semiconductors includes providing a process chamber and a source electrode adjacent to the process chamber. The process chamber contains a sample comprising a Ga-based compound semiconductor. The sample is in contact with a platen which is electrically connected to a first power supply, and the source electrode is electrically connected to a second power supply. The method includes flowing SiCl.sub.4 gas into the chamber, flowing Ar gas into the chamber, and flowing H.sub.2 gas into the chamber. RF power is supplied independently to the source electrode and the platen. A plasma is generated based on the gases in the process chamber, and regions of a surface of the sample adjacent to one or more masked portions of the surface are etched to create a substantially smooth etched surface including features having substantially vertical walls beneath the masked portions.

  2. LightLeaves: computer controlled kinetic reflection hologram installation and a brief discussion of earlier work

    NASA Astrophysics Data System (ADS)

    Connors Chen, Betsy

    2013-02-01

    LightLeaves is an installation combining leaf shaped, white light reflection holograms of landscape images with a special kinetic lighting device that houses a lamp and moving leaf shaped masks. The masks are controlled by an Arduino microcontroller and servomotors that position the masks in front of the illumination source of the holograms. The work is the most recent in a long series of landscapes that combine multi-hologram installations with computer controlled devices that play with the motion of the holograms, the light, sound or other elements in the work. LightLeaves was first exhibited at the Peabody Essex Museum in Salem, Massachusetts in a show titled "Eye Spy: Playing with Perception".

  3. Hybrid shearing and phase-shifting point diffraction interferometer

    DOEpatents

    Goldberg, Kenneth Alan; Naulleau, Patrick P.

    2003-06-03

    A new interferometry configuration combines the strengths of two existing interferometry methods, improving the quality and extending the dynamic range of both. On the same patterned mask, placed near the image-plane of an optical system under test, patterns for phase-shifting point diffraction interferometry and lateral shearing interferometry coexist. The former giving verifiable high accuracy for the measurement of nearly diffraction-limited optical systems. The latter enabling the measurement of optical systems with more than one wave of aberration in the system wavefront. The interferometry configuration is a hybrid shearing and point diffraction interferometer system for testing an optical element that is positioned along an optical path including: a source of electromagnetic energy in the optical path; a first beam splitter that is secured to a device that includes means for maneuvering the first beam splitter in a first position wherein the first beam splitter is in the optical path dividing light from the source into a reference beam and a test beam and in a second position wherein the first beam splitter is outside the optical path: a hybrid mask which includes a first section that defines a test window and at least one reference pinhole and a second section that defines a second beam splitter wherein the hybrid mask is secured to a device that includes means for maneuvering either the first section or the second section into the optical path positioned in an image plane that is created by the optical element, with the proviso that the first section of the hybrid mask is positioned in the optical path when first beam splitter is positioned in the optical path; and a detector positioned after the hybrid mask along the optical path.

  4. Microstructural investigation using synchrotron radiation X-ray microtomography reveals taste-masking mechanism of acetaminophen microspheres.

    PubMed

    Guo, Zhen; Yin, Xianzhen; Liu, Congbiao; Wu, Li; Zhu, Weifeng; Shao, Qun; York, Peter; Patterson, Laurence; Zhang, Jiwen

    2016-02-29

    The structure of solid drug delivery systems has considerable influence on drug release behaviors from particles and granules and also impacts other properties relevant to release characteristics such as taste. In this study, lipid-based microspheres of acetaminophen were prepared to mask the undesirable taste of drug and therefore to identify the optimal formulation for drug release. Synchrotron radiation X-ray computed microtomography (SR-μCT) was used to investigate the fine structural architectures of microspheres non-destructively at different sampling times during drug release test, which were simultaneously determined to quantitatively correlate the structural data with drug release behaviors. The results demonstrated that the polymeric formulation component, namely, cationic polymethacrylate (Eudragit E100), was the key factor to mask the bitter taste of acetaminophen by inhibiting immediate drug release thereby reducing the interaction intensity of the bitter material with the oral cavity taste buds. The structure and morphology of the microspheres were found to be influenced by the shape and particle size of the drug, which was also an important factor for taste-masking performance. The quantitative analysis generated detailed structural information which was correlated well with drug release behaviors. Thus, SR-μCT has been proved as a powerful tool to investigate the fine microstructure of particles and provides a new approach in the design of particles for taste masking. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Hot melt extrusion of ion-exchange resin for taste masking.

    PubMed

    Tan, David Cheng Thiam; Ong, Jeremy Jianming; Gokhale, Rajeev; Heng, Paul Wan Sia

    2018-05-30

    Taste masking is important for some unpleasant tasting bioactives in oral dosage forms. Among many methods available for taste-masking, use of ion-exchange resin (IER) holds promise. IER combined with hot melt extrusion (HME) may offer additional advantages over solvent methods. IER provides taste masking by complexing with the drug ions and preventing drug dissolution in the mouth. Drug-IER complexation approaches described in literatures are mainly based either on batch processing or column eluting. These methods of drug-IER complexation have obvious limitations such as high solvent volume requirements, multiprocessing steps and extended processing time. Thus, the objective of this study was to develop a single-step, solvent-free, continuous HME process for complexation of drug-IER. The screening study evaluated drug to IER ratio, types of IER and drug complexation methods. In the screening study, a potassium salt of a weakly acidic carboxylate-based cationic IER was found suitable for the HME method. Thereafter, optimization study was conducted by varying HME process parameters such as screw speed, extrusion temperature and drug to IER ratio. It was observed that extrusion temperature and drug to IER ratio are imperative in drug-IER complexation through HME. In summary, this study has established the feasibility of a continuous complexation method for drug to IER using HME for taste masking. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Mobile geographic information system (GIS) solution for pavement condition surveys.

    DOT National Transportation Integrated Search

    2012-06-28

    This report discusses the design and implementation of a software-based solution that will improve the data collection processes during the Pavement Condition Surveys (PCS) conducted by the State Materials Office (SMO) of the Florida Department of Tr...

  7. SU-E-T-541: Bolus Effect of Thermoplastic Masks in IMRT and VMAT Head and Neck Treatments

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

    Zhen, H; Nedzi, L; Chen, S

    2014-06-01

    Purpose: To quantitatively evaluate the bolus effect of thermoplalstic mask on patient skin dose during multi-field IMRT and VMAT treatment. Methods: The clinically approved target contours for five head and neck patients were deformably registered to an anthropomorphic Rando phantom. Two plans: Multifield IMRT plan with 7-9 beams and VMAT plan with 2-4 arcs were created for each patient following same dose constraints. 3mm skin was excluded from PTVs but not constrained during optimization. The prescription dose was 200-220 cGy/fraction. A thermoplastic head and shoulder mask was customized for the Rando phantom. Each plan was delivered to the phantom twicemore » with and without mask. During each delivery, two rectangular strips of EBT3 films (1cm x 6.8cm) were placed across the anterior upper and lower neck near PTVs to measure the surface dose. For consistency films were positioned at same locations for same patient. A total of 8 film strips were obtained for each patient. Film dose was calibrated in the range of 0-400cGy on the day of plan delivery. For dose comparison 3 regions of interests (ROIs) of 1×1 cm{sup 2} were selected at left, right and middle part of each film, resulting in 6 point doses at each plan delivery. Results: The films without mask show relatively uniform dose distribution while those with mask clearly show mesh pattern of mask, usually indicating an increase in skin dose. On average the increase in skin dose over all ROIs with mask was 31.9%(±14.8%) with a range of 11.4%- 58.4%. There is no statistically significant difference (p=0.44) between skin dose increase in VMAT (30.8%±15.3%) and IMRT delivery (33.0%±14.9%). Conclusion: Thermoplastic immobilization masks increase surface dose for HN patient by around 30%. The magnitude is comparable between multi-field IMRT and VMAT. Radiochromic EBT3 film serves as an effective tool to quantify bolus effect.« less

  8. Paving the way to a full chip gate level double patterning application

    NASA Astrophysics Data System (ADS)

    Haffner, Henning; Meiring, Jason; Baum, Zachary; Halle, Scott

    2007-10-01

    Double patterning lithography processes can offer significant yield enhancement for challenging circuit designs. Many decomposition (i.e. the process of dividing the layout design into first and second exposures) techniques are possible, but the focus of this paper is on the use of a secondary "cut" mask to trim away extraneous features left from the first exposure. This approach has the advantage that each exposure only needs to support a subset of critical features (e.g. dense lines with the first exposure, isolated spaces with the second one). The extraneous features ("printing assist features" or PrAFs) are designed to support the process window of critical features much like the role of the subresolution assist features (SRAFs) in conventional processes. However, the printing nature of PrAFs leads to many more design options, and hence a greater process and decomposition parameter exploration space, than are available for SRAFs. A decomposition scheme using PRAFs was developed for a gate level process. A critical driver of the work was to deliver improved across-chip linewidth variation (ACLV) performance versus an optimized single exposure process while providing support for a larger range of critical features. A variety of PRAF techniques were investigated by simulation, with a PrAF scheme similar to standard SRAF rules being chosen as the optimal solution [1]. This paper discusses aspects of the code development for an automated PrAF generation and placement scheme and the subsequent decomposition of a layout into two mask levels. While PrAF placement and decomposition is straightforward for layouts with pitch and orientation restrictions, it becomes rather complex for unrestricted layout styles. Because this higher complexity yields more irregularly shaped PrAFs, mask making becomes another critical driver of the optimum placement and clean-up strategies. Examples are given of how those challenges are met or can be successfully circumvented. During subsequent decomposition of the PrAF-enhanced layout into two independent mask levels, various geometric decomposition parameters have to be considered. As an example, the removal of PrAFs has to be guaranteed by a minimum required overlap of the cut mask opening past any PrAF edge. It is discussed that process assumptions such as CD tolerances and overlay as well as inter-level relationship ground rules need to be considered to successfully optimize the final decomposition scheme. Furthermore, simulation and experimental results regarding not only ACLV but also across-device linewidth variation (ADLV) are analyzed.

  9. [Carotid plaque assessment using inversion recovery T1 weighted-3 dimensions variable refocus flip angle turbo spin echo sampling perfection with application optimized contrast using different angle evolutions black blood imaging].

    PubMed

    Inoue, Yuji; Yoneyama, Masami; Nakamura, Masanobu; Ozaki, Satoshi; Ito, Kenjiro; Hiura, Mikio

    2012-01-01

    Vulnerable plaque can be attributed to induction of ischemic symptoms and magnetic resonance imaging of carotid artery is valuable to detect the plaque. Magnetization prepared rapid acquisition with gradient echo (MPRAGE) method could detect hemorrhagic vulnerable plaque as high intensity signal; however, blood flow is not sufficiently masked by this method. The contrast for plaque in T1 weighted image (T1WI) could not be obtained sufficiently with black blood image (BBI) by sampling perfection with application optimized contrast using different angle evolutions (SPACE) method as turbo spin echo (TSE). In addition, an appearance of artifact by slow flow is a problem. Considering these controversial situations in plaque imaging, we examined the modified BBI inversion recovery (IR)-SPACE in which IR was added for SPACE method so that the contrast for plaque in T1WI was optimized. We investigated the application of this method in plaque imaging. As a result of phantom imaging, the contrast for plaque in T1WI was definitely obtained by choosing an appropriate inversion time (TI) for the corresponding repetition time. In clinical cases, blood flow was sufficiently masked by IR-SPACE method and the plaque imaging was clearly obtained in clinical cases to the same extent as MPRAGE method. Since BBI with IR-SPACE method was derived from both IR pulse and flow void effect, this method could obtain the blood flow masking effect definitely. The present study suggested that SPACE method might be applicable to estimate properties of carotid artery plaque.

  10. Extending CO2 cryogenic aerosol cleaning for advanced optical and EUV mask cleaning

    NASA Astrophysics Data System (ADS)

    Varghese, Ivin; Bowers, Charles W.; Balooch, Mehdi

    2011-11-01

    Cryogenic CO2 aerosol cleaning being a dry, chemically-inert and residue-free process is used in the production of optical lithography masks. It is an attractive cleaning option for the mask industry to achieve the requirement for removal of all printable soft defects and repair debris down to the 50nm printability specification. In the technique, CO2 clusters are formed by sudden expansion of liquid from high to almost atmospheric pressure through an optimally designed nozzle orifice. They are then directed on to the soft defects or debris for momentum transfer and subsequent damage free removal from the mask substrate. Unlike aggressive acid based wet cleaning, there is no degradation of the mask after processing with CO2, i.e., no critical dimension (CD) change, no transmission/phase losses, or chemical residue that leads to haze formation. Therefore no restriction on number of cleaning cycles is required to be imposed, unlike other cleaning methods. CO2 aerosol cleaning has been implemented for several years as full mask final clean in production environments at several state of the art mask shops. Over the last two years our group reported successful removal of all soft defects without damage to the fragile SRAF features, zero adders (from the cleaning and handling mechanisms) down to a 50nm printability specification. In addition, CO2 aerosol cleaning is being utilized to remove debris from Post-RAVE repair of hard defects in order to achieve the goal of no printable defects. It is expected that CO2 aerosol cleaning can be extended to extreme ultraviolet (EUV) masks. In this paper, we report advances being made in nozzle design qualification for optimum snow properties (size, velocity and flux) using Phase Doppler Anemometry (PDA) technique. In addition the two new areas of focus for CO2 aerosol cleaning i.e. pellicle glue residue removal on optical masks, and ruthenium (Ru) film on EUV masks are presented. Usually, the residue left over after the pellicle has been removed from returned masks (after long term usage/exposure in the wafer fab), requires a very aggressive SPM wet clean, that drastically reduces the available budget for mask properties (CD, phase/transmission). We show that CO2aerosol cleaning can be utilized to remove the bulk of the glue residue effectively, while preserving the mask properties. This application required a differently designed nozzle to impart the required removal force for the sticky glue residue. A new nozzle was developed and qualified that resulted in PRE in the range of 92-98%. Results also include data on a patterned mask that was exposed in a lithography stepper in a wafer production environment. On EUV mask, our group has experimentally demonstrated that 50 CO2 cleaning cycles of Ru film on the EUV Front-side resulted in no appreciable reflectivity change, implying that no degradation of the Ru film occurs.

  11. Optimization of printing techniques for electrochemical biosensors

    NASA Astrophysics Data System (ADS)

    Zainuddin, Ahmad Anwar; Mansor, Ahmad Fairuzabadi Mohd; Rahim, Rosminazuin Ab; Nordin, Anis Nurashikin

    2017-03-01

    Electrochemical biosensors show great promise for point-of-care applications due to their low cost, portability and compatibility with microfluidics. The miniature size of these sensors provides advantages in terms of sensitivity, specificity and allows them to be mass produced in arrays. The most reliable fabrication technique for these sensors is lithography followed by metal deposition using sputtering or chemical vapor deposition techniques. This technique which is usually done in the cleanroom requires expensive masking followed by deposition. Recently, cheaper printing techniques such as screen-printing and ink-jet printing have become popular due to its low cost, ease of fabrication and mask-less method. In this paper, two different printing techniques namely inkjet and screen printing are demonstrated for an electrochemical biosensor. For ink-jet printing technique, optimization of key printing parameters, such as pulse voltages, drop spacing and waveform setting, in-house temperature and cure annealing for obtaining the high quality droplets, are discussed. These factors are compared with screen-printing parameters such as mesh size, emulsion thickness, minimum spacing of lines and curing times. The reliability and reproducibility of the sensors are evaluated using scotch tape test, resistivity and profile-meter measurements. It was found that inkjet printing is superior because it is mask-less, has minimum resolution of 100 µm compared to 200 µm for screen printing and higher reproducibility rate of 90% compared to 78% for screen printing.

  12. Optimization of plasma etching of SiO2 as hard mask for HgCdTe dry etching

    NASA Astrophysics Data System (ADS)

    Chen, Yiyu; Ye, Zhenhua; Sun, Changhong; Zhang, Shan; Xin, Wen; Hu, Xiaoning; Ding, Ruijun; He, Li

    2016-10-01

    HgCdTe is one of the dominating materials for infrared detection. To pattern this material, our group has proven the feasibility of SiO2 as a hard mask in dry etching process. In recent years, the SiO2 mask patterned by plasma with an auto-stopping layer of ZnS sandwiched between HgCdTe and SiO2 has been developed by our group. In this article, we will report the optimization of SiO2 etching on HgCdTe. The etching of SiO2 is very mature nowadays. Multiple etching recipes with deferent gas mixtures can be used. We utilized a recipe containing Ar and CHF3. With strictly controlled photolithography, the high aspect-ratio profile of SiO2 was firstly achieved on GaAs substrate. However, the same recipe could not work well on MCT because of the low thermal conductivity of HgCdTe and CdTe, resulting in overheated and deteriorated photoresist. By decreasing the temperature, the photoresist maintained its good profile. A starting table temperature around -5°C worked well enough. And a steep profile was achieved as checked by the SEM. Further decreasing of temperature introduced profile with beveled corner. The process window of the temperature is around 10°C. Reproducibility and uniformity were also confirmed for this recipe.

  13. Dissociable brain mechanisms underlying the conscious and unconscious control of behavior.

    PubMed

    van Gaal, Simon; Lamme, Victor A F; Fahrenfort, Johannes J; Ridderinkhof, K Richard

    2011-01-01

    Cognitive control allows humans to overrule and inhibit habitual responses to optimize performance in challenging situations. Contradicting traditional views, recent studies suggest that cognitive control processes can be initiated unconsciously. To further capture the relation between consciousness and cognitive control, we studied the dynamics of inhibitory control processes when triggered consciously versus unconsciously in a modified version of the stop task. Attempts to inhibit an imminent response were often successful after unmasked (visible) stop signals. Masked (invisible) stop signals rarely succeeded in instigating overt inhibition but did trigger slowing down of response times. Masked stop signals elicited a sequence of distinct ERP components that were also observed on unmasked stop signals. The N2 component correlated with the efficiency of inhibitory control when elicited by unmasked stop signals and with the magnitude of slowdown when elicited by masked stop signals. Thus, the N2 likely reflects the initiation of inhibitory control, irrespective of conscious awareness. The P3 component was much reduced in amplitude and duration on masked versus unmasked stop trials. These patterns of differences and similarities between conscious and unconscious cognitive control processes are discussed in a framework that differentiates between feedforward and feedback connections in yielding conscious experience.

  14. Matrix factorization-based data fusion for the prediction of lncRNA-disease associations.

    PubMed

    Fu, Guangyuan; Wang, Jun; Domeniconi, Carlotta; Yu, Guoxian

    2018-05-01

    Long non-coding RNAs (lncRNAs) play crucial roles in complex disease diagnosis, prognosis, prevention and treatment, but only a small portion of lncRNA-disease associations have been experimentally verified. Various computational models have been proposed to identify lncRNA-disease associations by integrating heterogeneous data sources. However, existing models generally ignore the intrinsic structure of data sources or treat them as equally relevant, while they may not be. To accurately identify lncRNA-disease associations, we propose a Matrix Factorization based LncRNA-Disease Association prediction model (MFLDA in short). MFLDA decomposes data matrices of heterogeneous data sources into low-rank matrices via matrix tri-factorization to explore and exploit their intrinsic and shared structure. MFLDA can select and integrate the data sources by assigning different weights to them. An iterative solution is further introduced to simultaneously optimize the weights and low-rank matrices. Next, MFLDA uses the optimized low-rank matrices to reconstruct the lncRNA-disease association matrix and thus to identify potential associations. In 5-fold cross validation experiments to identify verified lncRNA-disease associations, MFLDA achieves an area under the receiver operating characteristic curve (AUC) of 0.7408, at least 3% higher than those given by state-of-the-art data fusion based computational models. An empirical study on identifying masked lncRNA-disease associations again shows that MFLDA can identify potential associations more accurately than competing models. A case study on identifying lncRNAs associated with breast, lung and stomach cancers show that 38 out of 45 (84%) associations predicted by MFLDA are supported by recent biomedical literature and further proves the capability of MFLDA in identifying novel lncRNA-disease associations. MFLDA is a general data fusion framework, and as such it can be adopted to predict associations between other biological entities. The source code for MFLDA is available at: http://mlda.swu.edu.cn/codes.php? name = MFLDA. gxyu@swu.edu.cn. Supplementary data are available at Bioinformatics online.

  15. Lactate signalling regulates fungal β-glucan masking and immune evasion

    PubMed Central

    Ballou, Elizabeth R.; Avelar, Gabriela M.; Childers, Delma S.; Mackie, Joanna; Bain, Judith M.; Wagener, Jeanette; Kastora, Stavroula L.; Panea, Mirela D.; Hardison, Sarah E.; Walker, Louise A.; Erwig, Lars P.; Munro, Carol A.; Gow, Neil A.R.; Brown, Gordon D.; MacCallum, Donna M.; Brown, Alistair J.P.

    2017-01-01

    Summary Paragraph As they proliferate, fungi expose antigens at their cell surface that are potent stimulators of the innate immune response, and yet the commensal fungus Candida albicans is able to colonize immuno-competent individuals. We show that C. albicans may evade immune detection by presenting a moving immunological target. We report that the exposure of β-glucan, a key Pathogen Associated Molecular Pattern (PAMP) located at the cell surface of C. albicans and other pathogenic Candida species, is modulated in response to changes in carbon source. Exposure to lactate induces β-glucan masking in C. albicans via a signaling pathway that has recruited an evolutionarily conserved receptor (Gpr1) and transcriptional factor (Crz1) from other well-characterized pathways. In response to lactate, these regulators control the expression of cell wall related genes that contribute to β-glucan masking. This represents the first description of active PAMP masking by a Candida species, a process that reduces the visibility of the fungus to the immune system. PMID:27941860

  16. JAPE 91: Influence of terrain masking of the acoustic propagation of helicopter noise

    NASA Technical Reports Server (NTRS)

    Naz, P.

    1993-01-01

    The acoustic propagation in the case of a noise source masked by a small element of terrain has been investigated experimentally. These data have been measured during the 'terrain masking' experiment of the NATO JAPE 91 experimental campaign. The main objective of that experiment was to study the acoustic detection of a helicopter masked by a small hill. Microphones have been placed at different locations on the shadow zone of the hill to study the effect of the terrain obstruction on sound propagation. The results presented come from data measured by Atlas Elektronik and by ISL, and have been processed together. The terrain obstruction causes an excess attenuation of the SPL (Sound Pressure Level) for all the frequencies, but this attenuation is more effective for the high frequencies than for the low frequencies. Results typical of diffraction phenomena have been observed; the SPL is minimal at the foot of the hill and is relatively constant beyond it.

  17. Primer3_masker: integrating masking of template sequence with primer design software.

    PubMed

    Kõressaar, Triinu; Lepamets, Maarja; Kaplinski, Lauris; Raime, Kairi; Andreson, Reidar; Remm, Maido

    2018-06-01

    Designing PCR primers for amplifying regions of eukaryotic genomes is a complicated task because the genomes contain a large number of repeat sequences and other regions unsuitable for amplification by PCR. We have developed a novel k-mer based masking method that uses a statistical model to detect and mask failure-prone regions on the DNA template prior to primer design. We implemented the software as a standalone software primer3_masker and integrated it into the primer design program Primer3. The standalone version of primer3_masker is implemented in C. The source code is freely available at https://github.com/bioinfo-ut/primer3_masker/ (standalone version for Linux and macOS) and at https://github.com/primer3-org/primer3/ (integrated version). Primer3 web application that allows masking sequences of 196 animal and plant genomes is available at http://primer3.ut.ee/. maido.remm@ut.ee. Supplementary data are available at Bioinformatics online.

  18. Social learning spreads knowledge about dangerous humans among American crows.

    PubMed

    Cornell, Heather N; Marzluff, John M; Pecoraro, Shannon

    2012-02-07

    Individuals face evolutionary trade-offs between the acquisition of costly but accurate information gained firsthand and the use of inexpensive but possibly less reliable social information. American crows (Corvus brachyrhynchos) use both sources of information to learn the facial features of a dangerous person. We exposed wild crows to a novel 'dangerous face' by wearing a unique mask as we trapped, banded and released 7-15 birds at five study sites near Seattle, WA, USA. An immediate scolding response to the dangerous mask after trapping by previously captured crows demonstrates individual learning, while an immediate response by crows that were not captured probably represents conditioning to the trapping scene by the mob of birds that assembled during the capture. Later recognition of dangerous masks by lone crows that were never captured is consistent with horizontal social learning. Independent scolding by young crows, whose parents had conditioned them to scold the dangerous mask, demonstrates vertical social learning. Crows that directly experienced trapping later discriminated among dangerous and neutral masks more precisely than did crows that learned through social means. Learning enabled scolding to double in frequency and spread at least 1.2 km from the place of origin over a 5 year period at one site.

  19. Electron beam mask writer EBM-9500 for logic 7nm node generation

    NASA Astrophysics Data System (ADS)

    Matsui, Hideki; Kamikubo, Takashi; Nakahashi, Satoshi; Nomura, Haruyuki; Nakayamada, Noriaki; Suganuma, Mizuna; Kato, Yasuo; Yashima, Jun; Katsap, Victor; Saito, Kenichi; Kobayashi, Ryoei; Miyamoto, Nobuo; Ogasawara, Munehiro

    2016-10-01

    Semiconductor scaling is slowing down because of difficulties of device manufacturing below logic 7nm node generation. Various lithography candidates which include ArF immersion with resolution enhancement technology (like Inversed Lithography technology), Extreme Ultra Violet lithography and Nano Imprint lithography are being developed to address the situation. In such advanced lithography, shot counts of mask patterns are estimated to increase explosively in critical layers, and then it is hoped that multi beam mask writer (MBMW) is released to handle them within realistic write time. However, ArF immersion technology with multiple patterning will continue to be a mainstream lithography solution for most of the layers. Then, the shot counts in less critical layers are estimated to be stable because of the limitation of resolution in ArF immersion technology. Therefore, single beam mask writer (SBMW) can play an important role for mask production still, relative to MBMW. Also the demand of SBMW seems actually strong for the logic 7nm node. To realize this, we have developed a new SBMW, EBM-9500 for mask fabrication in this generation. A newly introduced electron beam source enables higher current density of 1200A/cm2. Heating effect correction function has also been newly introduced to satisfy the requirements for both pattern accuracy and throughput. In this paper, we will report the configuration and performance of EBM-9500.

  20. Enhancing Auditory Selective Attention Using a Visually Guided Hearing Aid.

    PubMed

    Kidd, Gerald

    2017-10-17

    Listeners with hearing loss, as well as many listeners with clinically normal hearing, often experience great difficulty segregating talkers in a multiple-talker sound field and selectively attending to the desired "target" talker while ignoring the speech from unwanted "masker" talkers and other sources of sound. This listening situation forms the classic "cocktail party problem" described by Cherry (1953) that has received a great deal of study over the past few decades. In this article, a new approach to improving sound source segregation and enhancing auditory selective attention is described. The conceptual design, current implementation, and results obtained to date are reviewed and discussed in this article. This approach, embodied in a prototype "visually guided hearing aid" (VGHA) currently used for research, employs acoustic beamforming steered by eye gaze as a means for improving the ability of listeners to segregate and attend to one sound source in the presence of competing sound sources. The results from several studies demonstrate that listeners with normal hearing are able to use an attention-based "spatial filter" operating primarily on binaural cues to selectively attend to one source among competing spatially distributed sources. Furthermore, listeners with sensorineural hearing loss generally are less able to use this spatial filter as effectively as are listeners with normal hearing especially in conditions high in "informational masking." The VGHA enhances auditory spatial attention for speech-on-speech masking and improves signal-to-noise ratio for conditions high in "energetic masking." Visual steering of the beamformer supports the coordinated actions of vision and audition in selective attention and facilitates following sound source transitions in complex listening situations. Both listeners with normal hearing and with sensorineural hearing loss may benefit from the acoustic beamforming implemented by the VGHA, especially for nearby sources in less reverberant sound fields. Moreover, guiding the beam using eye gaze can be an effective means of sound source enhancement for listening conditions where the target source changes frequently over time as often occurs during turn-taking in a conversation. http://cred.pubs.asha.org/article.aspx?articleid=2601621.

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