Role of Computer Aided Diagnosis (CAD) in the detection of pulmonary nodules on 64 row multi detector computed tomography.

PubMed

Prakashini, K; Babu, Satish; Rajgopal, K V; Kokila, K Raja

2016-01-01

To determine the overall performance of an existing CAD algorithm with thin-section computed tomography (CT) in the detection of pulmonary nodules and to evaluate detection sensitivity at a varying range of nodule density, size, and location. A cross-sectional prospective study was conducted on 20 patients with 322 suspected nodules who underwent diagnostic chest imaging using 64-row multi-detector CT. The examinations were evaluated on reconstructed images of 1.4 mm thickness and 0.7 mm interval. Detection of pulmonary nodules, initially by a radiologist of 2 years experience (RAD) and later by CAD lung nodule software was assessed. Then, CAD nodule candidates were accepted or rejected accordingly. Detected nodules were classified based on their size, density, and location. The performance of the RAD and CAD system was compared with the gold standard that is true nodules confirmed by consensus of senior RAD and CAD together. The overall sensitivity and false-positive (FP) rate of CAD software was calculated. Of the 322 suspected nodules, 221 were classified as true nodules on the consensus of senior RAD and CAD together. Of the true nodules, the RAD detected 206 (93.2%) and 202 (91.4%) by the CAD. CAD and RAD together picked up more number of nodules than either CAD or RAD alone. Overall sensitivity for nodule detection with the CAD program was 91.4%, and FP detection per patient was 5.5%. The CAD showed comparatively higher sensitivity for nodules of size 4-10 mm (93.4%) and nodules in hilar (100%) and central (96.5%) location when compared to RAD's performance. CAD performance was high in detecting pulmonary nodules including the small size and low-density nodules. CAD even with relatively high FP rate, assists and improves RAD's performance as a second reader, especially for nodules located in the central and hilar region and for small nodules by saving RADs time.

Role of Computer Aided Diagnosis (CAD) in the detection of pulmonary nodules on 64 row multi detector computed tomography

PubMed Central

Prakashini, K; Babu, Satish; Rajgopal, KV; Kokila, K Raja

2016-01-01

Aims and Objectives: To determine the overall performance of an existing CAD algorithm with thin-section computed tomography (CT) in the detection of pulmonary nodules and to evaluate detection sensitivity at a varying range of nodule density, size, and location. Materials and Methods: A cross-sectional prospective study was conducted on 20 patients with 322 suspected nodules who underwent diagnostic chest imaging using 64-row multi-detector CT. The examinations were evaluated on reconstructed images of 1.4 mm thickness and 0.7 mm interval. Detection of pulmonary nodules, initially by a radiologist of 2 years experience (RAD) and later by CAD lung nodule software was assessed. Then, CAD nodule candidates were accepted or rejected accordingly. Detected nodules were classified based on their size, density, and location. The performance of the RAD and CAD system was compared with the gold standard that is true nodules confirmed by consensus of senior RAD and CAD together. The overall sensitivity and false-positive (FP) rate of CAD software was calculated. Observations and Results: Of the 322 suspected nodules, 221 were classified as true nodules on the consensus of senior RAD and CAD together. Of the true nodules, the RAD detected 206 (93.2%) and 202 (91.4%) by the CAD. CAD and RAD together picked up more number of nodules than either CAD or RAD alone. Overall sensitivity for nodule detection with the CAD program was 91.4%, and FP detection per patient was 5.5%. The CAD showed comparatively higher sensitivity for nodules of size 4–10 mm (93.4%) and nodules in hilar (100%) and central (96.5%) location when compared to RAD's performance. Conclusion: CAD performance was high in detecting pulmonary nodules including the small size and low-density nodules. CAD even with relatively high FP rate, assists and improves RAD's performance as a second reader, especially for nodules located in the central and hilar region and for small nodules by saving RADs time. PMID:27578931

A tool to convert CAD models for importation into Geant4

NASA Astrophysics Data System (ADS)

Vuosalo, C.; Carlsmith, D.; Dasu, S.; Palladino, K.; LUX-ZEPLIN Collaboration

2017-10-01

The engineering design of a particle detector is usually performed in a Computer Aided Design (CAD) program, and simulation of the detector’s performance can be done with a Geant4-based program. However, transferring the detector design from the CAD program to Geant4 can be laborious and error-prone. SW2GDML is a tool that reads a design in the popular SOLIDWORKS CAD program and outputs Geometry Description Markup Language (GDML), used by Geant4 for importing and exporting detector geometries. Other methods for outputting CAD designs are available, such as the STEP format, and tools exist to convert these formats into GDML. However, these conversion methods produce very large and unwieldy designs composed of tessellated solids that can reduce Geant4 performance. In contrast, SW2GDML produces compact, human-readable GDML that employs standard geometric shapes rather than tessellated solids. This paper will describe the development and current capabilities of SW2GDML and plans for its enhancement. The aim of this tool is to automate importation of detector engineering models into Geant4-based simulation programs to support rapid, iterative cycles of detector design, simulation, and optimization.

Development of an aerosol chamber for calibration of 220Rn progeny detectors

NASA Astrophysics Data System (ADS)

Sorimachi, Atsuyuki; Ishikawa, Tetsuo; Tokonami, Shinji

2014-09-01

This paper describes an aerosol chamber system that can be used for calibrations and performance experiments of passive 220Rn progeny detectors. For the purpose of this study, an aerosol generation system using carnauba wax as the aerosol material was mounted into the 220Rn chamber. We used the chamber to measure characteristics of the equilibrium factor (F) of 220Rn and unattached fraction (fp) of 220Rn progeny, which are important parameters for dose estimation. The first experiment showed that continuous and stable generation of the unattached and aerosol-attached 220Rn progeny concentrations was obtained. We observed that the spatial distributions in the chamber of the vertical profiles of the unattached and aerosol-attached 220Rn progeny concentrations were homogeneous, as were the particle number concentration and count median diameter. The values of F and fp and their characteristics observed in this study were in the same range as the values reported from indoor measurements. We found that the characteristics of F and fp were dependent on the aerosol conditions (particle diameter and particle number concentration).

In Situ Aerosol Detector

NASA Technical Reports Server (NTRS)

Vakhtin, Andrei; Krasnoperov, Lev

2011-01-01

An affordable technology designed to facilitate extensive global atmospheric aerosol measurements has been developed. This lightweight instrument is compatible with newly developed platforms such as tethered balloons, blimps, kites, and even disposable instruments such as dropsondes. This technology is based on detection of light scattered by aerosol particles where an optical layout is used to enhance the performance of the laboratory prototype instrument, which allows detection of smaller aerosol particles and improves the accuracy of aerosol particle size measurement. It has been determined that using focused illumination geometry without any apertures is advantageous over using the originally proposed collimated beam/slit geometry (that is supposed to produce uniform illumination over the beam cross-section). The illumination source is used more efficiently, which allows detection of smaller aerosol particles. Second, the obtained integral scattered light intensity measured for the particle can be corrected for the beam intensity profile inhomogeneity based on the measured beam intensity profile and measured particle location. The particle location (coordinates) in the illuminated sample volume is determined based on the information contained in the image frame. The procedure considerably improves the accuracy of determination of the aerosol particle size.

Comparison between evaporative light scattering detection and charged aerosol detection for the analysis of saikosaponins.

PubMed

Eom, Han Young; Park, So-Young; Kim, Min Kyung; Suh, Joon Hyuk; Yeom, Hyesun; Min, Jung Won; Kim, Unyong; Lee, Jeongmi; Youm, Jeong-Rok; Han, Sang Beom

2010-06-25

Saikosaponins are triterpene saponins derived from the roots of Bupleurum falcatum L. (Umbelliferae), which has been traditionally used to treat fever, inflammation, liver diseases, and nephritis. It is difficult to analyze saikosaponins using HPLC-UV due to the lack of chromophores. Therefore, evaporative light scattering detection (ELSD) is used as a valuable alternative to UV detection. More recently, a charged aerosol detection (CAD) method has been developed to improve the sensitivity and reproducibility of ELSD. In this study, we compared CAD and ELSD methods in the simultaneous analysis of 10 saikosaponins, including saikosaponins-A, -B(1), -B(2), -B(3), -B(4), -C, -D, -G, -H and -I. A mixture of the 10 saikosaponins was injected into the Ascentis Express C18 column (100 mm x 4.6 mm, 2.7 microm) with gradient elution and detection with CAD and ELSD by splitting. We examined various factors that could affect the sensitivity of the detectors including various concentrations of additives, pH and flow rate of the mobile phase, purity of nitrogen gas and the CAD range. The sensitivity was determined based on the signal-to-noise ratio. The best sensitivity for CAD was achieved with 0.1 mM ammonium acetate at pH 4.0 in the mobile phase with a flow rate of 1.0 mL/min, and the CAD range at 100 pA, whereas that for ELSD was achieved with 0.01% acetic acid in the mobile phase with a flow rate at 0.8 mL/min. The purity of the nitrogen gas had only minor effects on the sensitivities of both detectors. Finally, the sensitivity for CAD was two to six times better than that of ELSD. Taken together, these results suggest that CAD provides a more sensitive analysis of the 10 saikosaponins than does ELSD. Copyright 2010 Elsevier B.V. All rights reserved.

A four parameter optimization and troubleshooting of a RPLC - charged aerosol detection stability indicating method for determination of S-lysophosphatidylcholines in a phospholipid formulation.

PubMed

Tam, James; Ahmad, Imad A Haidar; Blasko, Andrei

2018-06-05

A four parameter optimization of a stability indicating method for non-chromophoric degradation products of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), 1-stearoyl-sn-glycero-3-phosphocholine and 2-stearoyl-sn-glycero-3-phosphocholine was achieved using a reverse phase liquid chromatography-charged aerosol detection (RPLC-CAD) technique. Using the hydrophobic subtraction model of selectivity, a core-shell, polar embedded RPLC column was selected followed by gradient-temperature optimization, resulting in ideal relative peak placements for a robust, stability indicating separation. The CAD instrument parameters, power function value (PFV) and evaporator temperature were optimized for lysophosphatidylcholines to give UV absorbance detector-like linearity performance within a defined concentration range. The two lysophosphatidylcholines gave the same response factor in the selected conditions. System specific power function values needed to be set for the two RPLC-CAD instruments used. A custom flow-divert profile, sending only a portion of the column effluent to the detector, was necessary to mitigate detector response drifting effects. The importance of the PFV optimization for each instrument of identical build and how to overcome recovery issues brought on by the matrix effects from the lipid-RP stationary phase interaction is reported. Copyright © 2018 Elsevier B.V. All rights reserved.

Particulate and aerosol detector

NASA Technical Reports Server (NTRS)

Wortman, J. J.; Donovan, R. P.; Brooks, A. D.; Monteith, L. K.; Kinard, W. H.; Oneil, R. L. (Inventor)

1976-01-01

A device is described for counting aerosols and sorting them according to either size, mass or energy. The component parts are an accelerator, a capacitor sensor and a readout. The accelerator is a means for accelerating the aerosols toward the face of the capacitor sensor with such force that they partially penetrate the capacitor sensor, momentarily discharging it. The readout device is a means for counting the number of discharges of the capacitor sensor and measuring the amplitudes of these different discharges. The aerosols are accelerated by the accelerator in the direction of the metal layer with such force that they penetrate the metal and damage the oxide layers, thereby allowing the electrical charge on the capacitor to discharge through the damaged region. Each incident aerosol initiates a discharge path through the capacitor in such a fashion as to vaporize the conducting path. Once the discharge action is complete, the low resistance path no longer exists between the two capacitor plates and the capacitor is again able to accept a charge. The active area of the capacitor is reduced in size by the damaged area each time a discharge occurs.

Quantification aspects of constant pressure (ultra) high pressure liquid chromatography using mass-sensitive detectors with a nebulizing interface.

PubMed

Verstraeten, M; Broeckhoven, K; Lynen, F; Choikhet, K; Landt, K; Dittmann, M; Witt, K; Sandra, P; Desmet, G

2013-01-25

The present contribution investigates the quantitation aspects of mass-sensitive detectors with nebulizing interface (ESI-MSD, ELSD, CAD) in the constant pressure gradient elution mode. In this operation mode, the pressure is controlled and maintained at a set value and the liquid flow rate will vary according to the inverse mobile phase viscosity. As the pressure is continuously kept at the allowable maximum during the entire gradient run, the average liquid flow rate is higher compared to that in the conventional constant flow rate operation mode, thus shortening the analysis time. The following three mass-sensitive detectors were investigated: mass spectrometry detector (MS), evaporative light scattering detector (ELSD) and charged aerosol detector (CAD) and a wide variety of samples (phenones, polyaromatic hydrocarbons, wine, cocoa butter) has been considered. It was found that the nebulizing efficiency of the LC-interfaces of the three detectors under consideration changes with the increasing liquid flow rate. For the MS, the increasing flow rate leads to a lower peak area whereas for the ELSD the peak area increases compared to the constant flow rate mode. The peak area obtained with a CAD is rather insensitive to the liquid flow rate. The reproducibility of the peak area remains similar in both modes, although variation in system permeability compromises the 'long-term' reproducibility. This problem can however be overcome by running a flow rate program with an optimized flow rate and composition profile obtained from the constant pressure mode. In this case, the quantification remains reproducibile, despite any occuring variations of the system permeability. Furthermore, the same fragmentation pattern (MS) has been found in the constant pressure mode compared to the customary constant flow rate mode. Copyright © 2012 Elsevier B.V. All rights reserved.

Sulfate Aerosols Promote Lung Cancer Metastasis by Epigenetically Regulating the Epithelial-to-Mesenchymal Transition (EMT).

PubMed

Yun, Yang; Gao, Rui; Yue, Huifeng; Guo, Lin; Li, Guangke; Sang, Nan

2017-10-03

Secondary inorganic aerosols (SIA), particularly sulfate aerosols, are central particulate matter (PM) constituents of severe haze formation in China and exert profound impacts on human health; however, our understanding of the mechanisms by which sulfate aerosols cause malignancy in lung carcinogenesis remains incomplete. Here, we show that exposure to secondary inorganic aerosols induced the invasion and migration of lung epithelial cells, and that (NH 4 ) 2 SO 4 exerted the most serious effects in vitro and promoted lung tumor metastasis in vivo. This action was associated with alterations of phenotype markers in the epithelial-to-mesenchymal transition (EMT), such as the up-regulation of fibronectin (Fn1) and the down-regulation of E-cadherin (E-cad). Hypoxia-inducible factor 1α (HIF-1α)-Snail signaling, regulated by the generation of reactive oxygen species (ROS), was involved in the (NH 4 ) 2 SO 4 -induced EMT, and the potent antioxidant N-acetylcysteine (NAC) inhibited the activation of HIF-1α-Snail and blocked the EMT, cell invasion, and migration in response to (NH 4 ) 2 SO 4 . Additionally, CpG hypermethylation in the E-cad promoter regions partly contributed to the (NH 4 ) 2 SO 4 -regulated E-cad repression, and the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (5-Aza) restored the (NH 4 ) 2 SO 4 -induced down-regulation of E-cad. Our findings reveal a potential mechanistic basis for exploring the association between sulfate aerosol exposure and increased malignancy during lung carcinogenesis, and suggest new approaches for the treatment, improvement, and prevention of lung cancer resulting from sulfate aerosol exposure in severe haze-fog.

Development and validation of a hydrophilic interaction chromatography method coupled with a charged aerosol detector for quantitative analysis of nonchromophoric α-hydroxyamines, organic impurities of metoprolol.

PubMed

Xu, Qun; Tan, Shane; Petrova, Katya

2016-01-25

The European Pharmacopeia (EP) metoprolol impurities M and N are polar, nonchromophoric α-hydroxyamines, which are poorly retained in a conventional reversed-phase chromatographic system and are invisible for UV detection. Impurities M and N are currently analyzed by TLC methods in the EP as specified impurities and in the United States Pharmacopeia-National Formulary (USP-NF) as unspecified impurities. In order to modernize the USP monographs of metoprolol drug substances and related drug products, a hydrophilic interaction chromatography (HILIC) method coupled with a charged aerosol detector (CAD) was explored for the analysis of the two impurities. A comprehensive column screening that covers a variety of HILIC stationary phases (underivatized silica, amide, diol, amino, zwitterionic, polysuccinimide, cyclodextrin, and mixed-mode) and optimization of HPLC conditions led to the identification of a Halo Penta HILIC column (4.6 × 150 mm, 5 μm) and a mobile phase comprising 85% acetonitrile and 15% ammonium formate buffer (100 mM, pH 3.2). Efficient separations of metoprolol, succinic acid, and EP metoprolol impurities M and N were achieved within a short time frame (<8 min). The HILIC-CAD method was subsequently validated per USP validation guidelines with respect to specificity, robustness, linearity, accuracy, and precision, and could be incorporated into the current USP-NF monographs to replace the outdated TLC methods. Furthermore, the developed method was successfully applied to determine organic impurities in metoprolol drug substance (metoprolol succinate) and drug products (metoprolol tartrate injection and metoprolol succinate extended release tablets). Copyright © 2015 Elsevier B.V. All rights reserved.

Preliminary Experiments Using a Passive Detector for Measuring Indoor 220Rn Progeny Concentrations with an Aerosol Chamber.

PubMed

Sorimachi, Atsuyuki; Tokonami, Shinji; Kranrod, Chutima; Ishikawa, Tetsuo

2015-06-01

This paper describes preliminary experiments using a passive detector for integrating measurements of indoor thoron (²²⁰Rn) progeny concentrations with an aerosol chamber. A solid state nuclear detector (CR-39) covered with a thin aluminum-vaporized polyethylene plate (Mylar film) was used to detect only alpha particles emitted from ²¹²Po due to ²²⁰Rn progeny deposited on the detector surfaces. The initial experiment showed that Mylar film with area density of more than 5 mg cm⁻² was suitable to cut off completely alpha particles of 7.7 MeV from ²¹⁴Po of ²²²Rn progeny decay. In the experiment using the passive detector, it was observed that the net track density increased linearly with an increase of time-integrating ²²⁰Rn progeny concentration. As a result of dividing deposition rates by atom concentrations, the deposition velocity was given as 0.023 cm s⁻¹ for total ²²⁰Rn progeny. The model estimates of deposition velocities were 0.330 cm s⁻¹ for unattached ²²⁰Rn progeny and 0.0011 cm s⁻¹ for aerosol-attached ²²⁰Rn progeny using Lai-Nazaroff formulae. These deposition velocities were in the same range with the results reported in the literature. It was also found that the exposure experiments showed little influence of vertical profiles and surface orientations of the passive detector in the chamber on the detection responses, which was in good agreement with that in the model estimates. Furthermore, it was inferred that the main uncertainty of the passive detector was inhomogeneous deposition of Rn progeny onto its detection surfaces.

Development and Validation of a Chromatography Method Using Tandem UV/Charged Aerosol Detector for Simultaneous Determination of Amlodipine Besylate and Olmesartan Medoxomil: Application to Drug-Excipient Compatibility Study

PubMed Central

Brondi, Ariadne M.; Garcia, Jerusa S.

2017-01-01

A study was carried out to investigate compatibility of amlodipine besylate and olmesartan medoxomil with a variety of pharmaceutical excipients. Both drugs are antihypertensive agents that can be administered alone, in monotherapy, or in pharmaceutical association. The studies were performed using binary and ternary mixtures, and samples were stored for 3 and 6 months at 40°C under 75% relative humidity and dry conditions. For this study, a method based on high-performance liquid chromatography (HPLC) was developed and validated for the simultaneous determination of amlodipine besylate and olmesartan medoxomil in samples from pharmaceutical preformulation studies using diode array detector (DAD) and charged aerosol detector (CAD). The runtime per sample was 10 min with retention time of 7.926 min and 4.408 min for amlodipine and olmesartan, respectively. The validation was performed according to ICH guidelines. The calibration curve presents linear dynamic range from 12 to 250 μg mL−1 for amlodipine and from 25 to 500 μg mL−1 for olmesartan with coefficient of determination (R2 ≥ 0.9908) while repeatability and reproducibility (expressed as relative standard deviation) were lower than 1.0%. The excipients such as corn starch, croscarmellose sodium, magnesium stearate, polyvinyl alcohol, talc, polyvinylpyrrolidone, lactose monohydrate, and polyethylene glycol showed potential incompatibilities after accelerated stability testing. PMID:29391967

Cloud and aerosol polarimetric imager

NASA Astrophysics Data System (ADS)

Zhang, Junqiang; Shao, Jianbing; Yan, Changxiang

2014-02-01

Cloud and Aerosol Polarimetric Imager (CAPI), which is the first onboard cloud and aerosol Polarimetric detector of CHINA, is developed to get cloud and aerosol data of atmosphere to retrieve aerosol optical and microphysical properties to increase the reversion precision of greenhouse gasses (GHGs). The instrument is neither a Polarization and Direction of Earth's Reflectance (POLDER) nor a Directional Polarimetric Camera (DPC) type polarized camera. It is a multispectral push broom system using linear detectors, and can get 5 bands spectral data, from ultraviolet (UV) to SWIR, of the same ground feature at the same time without any moving structure. This paper describes the CAPI instrument characteristics, composition, calibration, and the nearest development.

Two-Column Aerosol Project: Aerosol Light Extinction Measurements Field Campaign Report

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

Dubey, Manvendra; Aiken, Allison; Berg, Larry

We deployed Aerodyne Research Inc.’s first Cavity Attenuated Phase Shift extinction (CAPS PMex) monitor (built by Aerodyne) that measures light extinction by using a visible-light-emitting diode (LED) as a light source, a sample cell incorporating two high-reflectivity mirrors centered at the wavelength of the LED, and a vacuum photodiode detector in Cape Cod in 2012/13 for the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility’s Two-Column Aerosol Project (TCAP). The efficacy of this instrument is based on the fact that aerosols are broadband scatterers and absorbers of light. The input LED is square-wave modulated and passedmore » through the sample cell that distorts it due to exponential decay by aerosol light absorption and scattering; this is measured at the detector. The amount of phase shift of the light at the detector is used to determine the light extinction. This extinction measurement provides an absolute value, requiring no calibration. The goal was to compare the CAPS performance with direct measurements of absorption with ARM’s baseline photoacoustic soot spectrometer (PASS-3) and nephelometer instruments to evaluate its performance.« less

An application protocol for CAD to CAD transfer of electronic information

NASA Technical Reports Server (NTRS)

Azu, Charles C., Jr.

1993-01-01

The exchange of Computer Aided Design (CAD) information between dissimilar CAD systems is a problem. This is especially true for transferring electronics CAD information such as multi-chip module (MCM), hybrid microcircuit assembly (HMA), and printed circuit board (PCB) designs. Currently, there exists several neutral data formats for transferring electronics CAD information. These include IGES, EDIF, and DXF formats. All these formats have limitations for use in exchanging electronic data. In an attempt to overcome these limitations, the Navy's MicroCIM program implemented a project to transfer hybrid microcircuit design information between dissimilar CAD systems. The IGES (Initial Graphics Exchange Specification) format is used since it is well established within the CAD industry. The goal of the project is to have a complete transfer of microelectronic CAD information, using IGES, without any data loss. An Application Protocol (AP) is being developed to specify how hybrid microcircuit CAD information will be represented by IGES entity constructs. The AP defines which IGES data items are appropriate for describing HMA geometry, connectivity, and processing as well as HMA material characteristics.

CAD/CAE Integration Enhanced by New CAD Services Standard

NASA Technical Reports Server (NTRS)

Claus, Russell W.

2002-01-01

A Government-industry team led by the NASA Glenn Research Center has developed a computer interface standard for accessing data from computer-aided design (CAD) systems. The Object Management Group, an international computer standards organization, has adopted this CAD services standard. The new standard allows software (e.g., computer-aided engineering (CAE) and computer-aided manufacturing software to access multiple CAD systems through one programming interface. The interface is built on top of a distributed computing system called the Common Object Request Broker Architecture (CORBA). CORBA allows the CAD services software to operate in a distributed, heterogeneous computing environment.

Aerosol Optical Depth Changes in Version 4 CALIPSO Level 2 Product

NASA Astrophysics Data System (ADS)

Kim, M. H.; Omar, A. H.; Tackett, J. L.; Vaughan, M.; Winker, D. M.; Trepte, C. R.; Hu, Y.; Liu, Z.

2017-12-01

The Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) version 4 (V4) products were released in November 2016 with substantial enhancements. There have been improvements in the V4 CALIOP level 2 aerosol optical depth (AOD) compared to V3 (version 3) due to various factors. To analyze the AOD changes we selected every bin whose the vertical feature mask (VFM) is determined as aerosol for either V3 or V4 (or both) from the CALIOP level 2 profile product from 2007 to 2009. We isolated the AOD differences due to changes in six factors: layer detection, cloud-aerosol discrimination (CAD), surface detection, stratospheric aerosol, aerosol subtype, and lidar ratio. Total mean (± standard deviation) column AOD increases from V3 in V4 by 0.051±0.296 and 0.075±0.383 for daytime and nighttime, respectively. Dominant reasons for AOD change are differences in aerosol layer detection, CAD, aerosol subtype, and lidar ratio between V3 and V4 with AOD changes of 0.011 (0.027), 0.018 (0.015), -0.002 (0.009), 0.016 (0.017) for daytime (nighttime), respectively. CALIOP AOD was compared with the Moderate Resolution Imaging Spectroradiometer (MODIS) and Aerosol Robotic Network (AERONET) for both V3 and V4. The comparison shows that mean AOD biases with AERONET and MODIS (collection 6, over ocean) decrease in V4 compared to V3. Mean AOD difference with MODIS for cloud-screened data changes from -0.012±0.079 in V3 to -0.008±0.067 in V4. Mean AOD difference with AERONET is -0.071±0.207 and -0.023±0.233 for V3 and V4, respectively. There is reduction in the CALIOP AOD negative bias with respect to both MODIS and AERONET.

Determination of Gentamicin Sulphate Composition and Related Substances in Pharmaceutical Preparations by LC with Charged Aerosol Detection

PubMed Central

Stypulkowska, Karolina; Fijalek, Zbigniew; Sarna, Katarzyna

2010-01-01

A new, simple and repeatable liquid chromatography method with charged aerosol detection (LC-CAD) for the determination of gentamicin sulphate composition and related substances has been developed. Gentamicin lacks of chromophores, therefore its determination is quite problematic. Using a universal CAD enables to achieve good separation without sample derivatization. Mass spectrometry was employed to confirm the LC-CAD peak profile. The proposed method was validated and applied for the determination of gentamicin sulphate composition and related substances in pharmaceutical preparations. PMID:21212825

A thermoluminescent method for aerosol characterization

NASA Technical Reports Server (NTRS)

Long, E. R., Jr.; Rogowski, R. S.

1976-01-01

A thermoluminescent method has been used to study the interactions of aerosols with ozone. The preliminary results show that ozone reacts with many compounds found in aerosols, and that the thermoluminescence curves obtained from ozonated aerosols are characteristic of the aerosol. The results suggest several important applications of the thermoluminescent method: development of a detector for identification of effluent sources; a sensitive experimental tool for study of heterogeneous chemistry; evaluation of importance of aerosols in atmospheric chemistry; and study of formation of toxic, electronically excited species in airborne particles.

Comparison of ultraviolet detection and charged aerosol detection methods for liquid-chromatographic determination of protoescigenin.

PubMed

Filip, Katarzyna; Grynkiewicz, Grzegorz; Gruza, Mariusz; Jatczak, Kamil; Zagrodzki, Bogdan

2014-01-01

Escin, a complex mixture of pentacyclic triterpene saponins obtained from horse chestnut seeds extract (HCSE; Aesculus hippocastanum L.), constitutes a traditional herbal active substance of preparations (drugs) used for a treatment of chronic venous insufficiency and capillary blood vessel leakage. A new approach to exploitation of pharmacological potential of this saponin complex has been recently proposed, in which the β-escin mixture is perceived as a source of a hitherto unavailable raw material, pentacyclic triterpene aglycone-protoescigenin. Although many liquid chromatography methods are described in the literature for saponins determination, analysis of protoescigenin is barely mentioned. In this work, a new ultra-high performance liquid chromatography (UHPLC) method developed for protoescigenin quantification has been described. CAD (charged aerosol detection), as a relatively new detection method based on aerosol charging, has been applied in this method as an alternative to ultraviolet (UV) detection. The influence of individual parameters on CAD response and sensitivity was studied. The detection was performed using CAD and UV (200 nm) simultaneously and the results were compared with reference to linearity, accuracy, precision and limit of detection.

ProperCAD: A portable object-oriented parallel environment for VLSI CAD

NASA Technical Reports Server (NTRS)

Ramkumar, Balkrishna; Banerjee, Prithviraj

1993-01-01

Most parallel algorithms for VLSI CAD proposed to date have one important drawback: they work efficiently only on machines that they were designed for. As a result, algorithms designed to date are dependent on the architecture for which they are developed and do not port easily to other parallel architectures. A new project under way to address this problem is described. A Portable object-oriented parallel environment for CAD algorithms (ProperCAD) is being developed. The objectives of this research are (1) to develop new parallel algorithms that run in a portable object-oriented environment (CAD algorithms using a general purpose platform for portable parallel programming called CARM is being developed and a C++ environment that is truly object-oriented and specialized for CAD applications is also being developed); and (2) to design the parallel algorithms around a good sequential algorithm with a well-defined parallel-sequential interface (permitting the parallel algorithm to benefit from future developments in sequential algorithms). One CAD application that has been implemented as part of the ProperCAD project, flat VLSI circuit extraction, is described. The algorithm, its implementation, and its performance on a range of parallel machines are discussed in detail. It currently runs on an Encore Multimax, a Sequent Symmetry, Intel iPSC/2 and i860 hypercubes, a NCUBE 2 hypercube, and a network of Sun Sparc workstations. Performance data for other applications that were developed are provided: namely test pattern generation for sequential circuits, parallel logic synthesis, and standard cell placement.

Teaching for CAD Expertise

ERIC Educational Resources Information Center

Chester, Ivan

2007-01-01

CAD (Computer Aided Design) has now become an integral part of Technology Education. The recent introduction of highly sophisticated, low-cost CAD software and CAM hardware capable of running on desktop computers has accelerated this trend. There is now quite widespread introduction of solid modeling CAD software into secondary schools but how…

[The CAD-S, an instrument for the assessment of adaptation to divorce - separation].

PubMed

Yárnoz Yaben, Sagrario; Comino González, Priscila

2010-02-01

The CAD-S, an Instrument for the Assessment of Adaptation to Divorce - Separation. This paper presents an instrument for the evaluation of the adaptation to divorce-separation. The CAD-S is a questionnaire created in Spanish, made up of 20 items whose aim is the evaluation of the family's adaptation to divorce-separation, using one of the parents as informant. Data were collected in four different samples of divorced persons and their children from different autonomous comunities from the Spanish state. 223 parents and 160 children from divorced families took part in this study. Four factors emerged, accounting for 52.39 percent of the total variance: psychological and emotional difficulties, conflict with the ex-partner, disposition to co-parentality, and negative outcomes of separation for children. The results suggest that CAD-S appears to be a reliable and valid instrument, with high internal consistency (Cronbach's alpha) and adequate construct validity supported by its relations with measures of satisfaction with life (SWLS), in the case of parents, and conduct problems (CBCL) for children.

CAD for small hydro projects

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

Bishop, N.A. Jr.

1994-04-01

Over the past decade, computer-aided design (CAD) has become a practical and economical design tool. Today, specifying CAD hardware and software is relatively easy once you know what the design requirements are. But finding experienced CAD professionals is often more difficult. Most CAD users have only two or three years of design experience; more experienced design personnel are frequently not CAD literate. However, effective use of CAD can be the key to lowering design costs and improving design quality--a quest familiar to every manager and designer. By emphasizing computer-aided design literacy at all levels of the firm, a Canadian joint-venturemore » company that specializes in engineering small hydroelectric projects has cut costs, become more productive and improved design quality. This article describes how they did it.« less

Biological aerosol background characterization

NASA Astrophysics Data System (ADS)

Blatny, Janet; Fountain, Augustus W., III

2011-05-01

To provide useful information during military operations, or as part of other security situations, a biological aerosol detector has to respond within seconds or minutes to an attack by virulent biological agents, and with low false alarms. Within this time frame, measuring virulence of a known microorganism is extremely difficult, especially if the microorganism is of unknown antigenic or nucleic acid properties. Measuring "live" characteristics of an organism directly is not generally an option, yet only viable organisms are potentially infectious. Fluorescence based instruments have been designed to optically determine if aerosol particles have viability characteristics. Still, such commercially available biological aerosol detection equipment needs to be improved for their use in military and civil applications. Air has an endogenous population of microorganisms that may interfere with alarm software technologies. To design robust algorithms, a comprehensive knowledge of the airborne biological background content is essential. For this reason, there is a need to study ambient live bacterial populations in as many locations as possible. Doing so will permit collection of data to define diverse biological characteristics that in turn can be used to fine tune alarm algorithms. To avoid false alarms, improving software technologies for biological detectors is a crucial feature requiring considerations of various parameters that can be applied to suppress alarm triggers. This NATO Task Group will aim for developing reference methods for monitoring biological aerosol characteristics to improve alarm algorithms for biological detection. Additionally, they will focus on developing reference standard methodology for monitoring biological aerosol characteristics to reduce false alarm rates.

Evaluation of Five Microcomputer CAD Packages.

ERIC Educational Resources Information Center

Leach, James A.

1987-01-01

Discusses the similarities, differences, advanced features, applications and number of users of five microcomputer computer-aided design (CAD) packages. Included are: "AutoCAD (V.2.17)"; "CADKEY (V.2.0)"; "CADVANCE (V.1.0)"; "Super MicroCAD"; and "VersaCAD Advanced (V.4.00)." Describes the…

A Comparison of the Marginal and Internal Fit of Cobalt- Chromium Copings Fabricated by Two Different CAD/CAM Systems (CAD/ Milling, CAD/ Ceramill Sintron).

PubMed

Vojdani, Mahroo; Torabi, Kianoosh; Atashkar, Berivan; Heidari, Hossein; Torabi Ardakani, Mahshid

2016-12-01

Marginal fitness is the most important criteria for evaluation of the clinical acceptability of a cast restoration. Marginal gap which is due to cement solubility and plaque retention is potentially detrimental to both tooth and periodontal tissues. This in vitro study aimed to evaluate the marginal and internal fit of cobalt- chromium (Co-Cr) copings fabricated by two different CAD/CAM systems: (CAD/ milling and CAD/ Ceramill Sintron). We prepared one machined standard stainless steel master model with following dimensions: 7 mm height, 5mm diameter, 90˚ shoulder marginal finish line with 1 mm width, 10˚ convergence angle and anti-rotational surface on the buccal aspect of the die. There were 10 copings produced from hard presintered Co-Cr blocks according to CAD/ Milling technique and ten copings from soft non- presintered Co-Cr blocks according to CAD/ Ceramill Sintron technique. Marginal and internal accuracies of copings were documented by the replica technique. Replicas were examined at ten reference points under a digital microscope (230X). The Student's t-test was used for statistical analysis. p < 0.001 was considered significant. Statistically significant differences existed between the groups ( p < 0.001). The CAD/milling group (hard copings) had a mean marginal discrepancy (MD) of 104 µm, axial discrepancy (AD) of 23 µm and occlusal discrepancy of 130 µm. For CAD/ Ceramill Sintron group, these values were 195 µm (MD), 46 µm (AD), and 232 µm (OD). Internal total discrepancy (ITD) for the CAD/milling group was 77 µm, whereas for the CAD/Ceramill Sintron group was 143 µm. Hard presintered Co-Cr copings had significantly higher marginal and internal accuracies compared to the soft non-presintered copings.

A Comparison of the Marginal and Internal Fit of Cobalt- Chromium Copings Fabricated by Two Different CAD/CAM Systems (CAD/ Milling, CAD/ Ceramill Sintron)

PubMed Central

Vojdani, Mahroo; Torabi, Kianoosh; Atashkar, Berivan; Heidari, Hossein; Torabi Ardakani, Mahshid

2016-01-01

Statement of the Problem: Marginal fitness is the most important criteria for evaluation of the clinical acceptability of a cast restoration. Marginal gap which is due to cement solubility and plaque retention is potentially detrimental to both tooth and periodontal tissues. Purpose: This in vitro study aimed to evaluate the marginal and internal fit of cobalt- chromium (Co-Cr) copings fabricated by two different CAD/CAM systems: (CAD/ milling and CAD/ Ceramill Sintron). Materials and Method: We prepared one machined standard stainless steel master model with following dimensions: 7 mm height, 5mm diameter, 90˚ shoulder marginal finish line with 1 mm width, 10˚ convergence angle and anti-rotational surface on the buccal aspect of the die. There were 10 copings produced from hard presintered Co-Cr blocks according to CAD/ Milling technique and ten copings from soft non- presintered Co-Cr blocks according to CAD/ Ceramill Sintron technique. Marginal and internal accuracies of copings were documented by the replica technique. Replicas were examined at ten reference points under a digital microscope (230X). The Student's t-test was used for statistical analysis. p< 0.001 was considered significant. Results: Statistically significant differences existed between the groups (p< 0.001). The CAD/milling group (hard copings) had a mean marginal discrepancy (MD) of 104 µm, axial discrepancy (AD) of 23 µm and occlusal discrepancy of 130 µm. For CAD/ Ceramill Sintron group, these values were 195 µm (MD), 46 µm (AD), and 232 µm (OD). Internal total discrepancy (ITD) for the CAD/milling group was 77 µm, whereas for the CAD/Ceramill Sintron group was 143 µm. Conclusion: Hard presintered Co-Cr copings had significantly higher marginal and internal accuracies compared to the soft non-presintered copings. PMID:27942545

Cool-and Unusual-CAD Applications

ERIC Educational Resources Information Center

Calhoun, Ken

2004-01-01

This article describes several very useful applications of AutoCAD that may lie outside the normal scope of application. AutoCAD commands used in this article are based on AutoCAD 2000I. The author and his students used a Hewlett Packard 750C DesignJet plotter for plotting. (Contains 5 figures and 5 photos.)

CAD: Designs on Business.

ERIC Educational Resources Information Center

Milburn, Ken

1988-01-01

Provides a general review of the field of Computer-Aided Design Software including specific reviews of "Autosketch,""Generic CADD,""Drafix 1 Plus,""FastCAD," and "Autocad Release 9." Brief articles include "Blueprint for Generation,""CAD for Every Department,""Ideas…

Performance Testing of Tracer Gas and Tracer Aerosol Detectors for use in Radionuclide NESHAP Compliance Testing

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

Fuehne, David Patrick; Lattin, Rebecca Renee

The Rad-NESHAP program, part of the Air Quality Compliance team of LANL’s Compliance Programs group (EPC-CP), and the Radiation Instrumentation & Calibration team, part of the Radiation Protection Services group (RP-SVS), frequently partner on issues relating to characterizing air flow streams. This memo documents the most recent example of this partnership, involving performance testing of sulfur hexafluoride detectors for use in stack gas mixing tests. Additionally, members of the Rad-NESHAP program performed a functional trending test on a pair of optical particle counters, comparing results from a non-calibrated instrument to a calibrated instrument. Prior to commissioning a new stack samplingmore » system, the ANSI Standard for stack sampling requires that the stack sample location must meet several criteria, including uniformity of tracer gas and aerosol mixing in the air stream. For these mix tests, tracer media (sulfur hexafluoride gas or liquid oil aerosol particles) are injected into the stack air stream and the resulting air concentrations are measured across the plane of the stack at the proposed sampling location. The coefficient of variation of these media concentrations must be under 20% when evaluated over the central 2/3 area of the stack or duct. The instruments which measure these air concentrations must be tested prior to the stack tests in order to ensure their linear response to varying air concentrations of either tracer gas or tracer aerosol. The instruments used in tracer gas and aerosol mix testing cannot be calibrated by the LANL Standards and Calibration Laboratory, so they would normally be sent off-site for factory calibration by the vendor. Operational requirements can prevent formal factory calibration of some instruments after they have been used in hazardous settings, e.g., within a radiological facility with potential airborne contamination. The performance tests described in this document are intended to demonstrate the

CAD Services: an Industry Standard Interface for Mechanical CAD Interoperability

NASA Technical Reports Server (NTRS)

Claus, Russell; Weitzer, Ilan

2002-01-01

Most organizations seek to design and develop new products in increasingly shorter time periods. At the same time, increased performance demands require a team-based multidisciplinary design process that may span several organizations. One approach to meet these demands is to use 'Geometry Centric' design. In this approach, design engineers team their efforts through one united representation of the design that is usually captured in a CAD system. Standards-based interfaces are critical to provide uniform, simple, distributed services that enable the 'Geometry Centric' design approach. This paper describes an industry-wide effort, under the Object Management Group's (OMG) Manufacturing Domain Task Force, to define interfaces that enable the interoperability of CAD, Computer Aided Manufacturing (CAM), and Computer Aided Engineering (CAE) tools. This critical link to enable 'Geometry Centric' design is called: Cad Services V1.0. This paper discusses the features of this standard and proposed application.

Lipid analysis via HPLC with a charged aerosol detector

USDA-ARS?s Scientific Manuscript database

Most lipid extracts are a mixture of saturated and unsaturated molecules. Therefore, the most successful HPLC detectors for the quantitative analysis of lipids have involved the use of “universal” or “mass” detectors such as flame ionization detectors (FID) and evaporative light scattering detectors...

Compact Efficient Lidar Receiver for Measuring Atmospheric Aerosols

NASA Technical Reports Server (NTRS)

Gili, Christopher; De Young, Russell

2006-01-01

A small, light weight, and efficient aerosol lidar receiver was constructed and tested. Weight and space savings were realized by using rigid optic tubes and mounting cubes to package the steering optics and detectors in a compact assembly. The receiver had a 1064nm channel using an APD detector. The 532nm channel was split (90/10) into an analog channel (90%) and a photon counting channel (10%). The efficiency of the 1064nm channel with optical filter was 44.0%. The efficiency of the analog 532nm channel was 61.4% with the optical filter, and the efficiency of the 532nm photon counting channel was 7.6% with the optical filter. The results of the atmospheric tests show that the detectors were able to consistently return accurate results. The lidar receiver was able to detect distinct cloud layers, and the lidar returns also agreed across the different detectors. The use of a light weight fiber-coupled telescope reduced weight and allowed great latitude in detector assembly positioning due to the flexibility enabled by the use of fiber optics. The receiver is now ready to be deployed for aircraft or ground based aerosol lidar measurements.

CAD/CAM. High-Technology Training Module.

ERIC Educational Resources Information Center

Zuleger, Robert

This high technology training module is an advanced course on computer-assisted design/computer-assisted manufacturing (CAD/CAM) for grades 11 and 12. This unit, to be used with students in advanced drafting courses, introduces the concept of CAD/CAM. The content outline includes the following seven sections: (1) CAD/CAM software; (2) computer…

CAD/CAM data management

NASA Technical Reports Server (NTRS)

Bray, O. H.

1984-01-01

The role of data base management in CAD/CAM, particularly for geometric data is described. First, long term and short term objectives for CAD/CAM data management are identified. Second, the benefits of the data base management approach are explained. Third, some of the additional work needed in the data base area is discussed.

Project CAD as of July 1978: CAD support project, situation in July 1978

NASA Technical Reports Server (NTRS)

Boesch, L.; Lang-Lendorff, G.; Rothenberg, R.; Stelzer, V.

1979-01-01

The structure of Computer Aided Design (CAD) and the requirements for program developments in past and future are described. The actual standard and the future aims of CAD programs are presented. The developed programs in: (1) civil engineering; (2) mechanical engineering; (3) chemical engineering/shipbuilding; (4) electrical engineering; and (5) general programs are discussed.

Role of CadC and CadD in the 2,4-dichlorophenoxyacetic acid oxygenase system of Sphingomonas agrestis 58-1.

PubMed

Kijima, Kumiko; Mita, Hajime; Kawakami, Mitsuyasu; Amada, Kei

2018-02-02

In the present study, we confirm that 2,4-dichlorophenoxyacetic acid (2,4-D) oxygenase from Sphingomonas agrestis 58-1 belongs to the family of Rieske non-heme iron aromatic ring-hydroxylating oxygenases, which comprise a core enzyme (oxygenase), ferredoxin, and oxidoreductase. It has previously been shown that cadAB genes are necessary for the conversion of 2,4-D to 2,4-dichlorophenol; however, the respective roles of ferredoxin and oxidoreductase in the 2,4-D oxygenase system from S. agrestis 58-1 remain unknown. Using nucleotide sequence analysis of the plasmid pCADAB1 from Sphingomonas sp. ERG5, which degrades 4-chloro-2-methylphenoxyacetic acid and 2,4-D, Nielsen et al. identified orf95, upstream of cadA, and orf98, downstream of cadB, which were predicted and designated as cadD (oxidoreductase) and cadC (ferredoxin), respectively (Nielsen et al., PLoS One, 8, 1-9, 2013). These designations were the result of sequence analysis; therefore, we constructed an expression system of CadABC and CadABCD in Escherichia coli and assayed their enzyme activities. Our findings indicate that CadC is essential for the activity of 2,4-D oxygenase and CadD promotes CadABC activity in recombinant E. coli cells. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

PIXE Analysis of Indoor Aerosols

NASA Astrophysics Data System (ADS)

Johnson, Christopher; Turley, Colin; Moore, Robert; Battaglia, Maria; Labrake, Scott; Vineyard, Michael

2011-10-01

We have performed a proton-induced X-ray emission (PIXE) analysis of aerosol samples collected in academic buildings at Union College to investigate the air quality in these buildings and the effectiveness of their air filtration systems. This is also the commissioning experiment for a new scattering chamber in the Union College Ion-Beam Analysis Laboratory. The aerosol samples were collected on Kapton foils using a nine-stage cascade impactor that separates particles according to their aerodynamic size. The foils were bombarded with beams of 2.2-MeV protons from the Union College 1.1-MV Pelletron Accelerator and the X-ray products were detected with an Amptek silicon drift detector. After subtracting the contribution from the Kapton foils, the X-ray energy spectra of the aerosol samples were analyzed using GUPIX software to determine the elemental concentrations of the samples. We will describe the collection of the aerosol samples, discuss the PIXE analysis, and present the results.

The Enzyme Activity and Substrate Specificity of Two Major Cinnamyl Alcohol Dehydrogenases in Sorghum (Sorghum bicolor), SbCAD2 and SbCAD4.

PubMed

Jun, Se-Young; Walker, Alexander M; Kim, Hoon; Ralph, John; Vermerris, Wilfred; Sattler, Scott E; Kang, ChulHee

2017-08-01

Cinnamyl alcohol dehydrogenase (CAD) catalyzes the final step in monolignol biosynthesis, reducing sinapaldehyde, coniferaldehyde, and p -coumaraldehyde to their corresponding alcohols in an NADPH-dependent manner. Because of its terminal location in monolignol biosynthesis, the variation in substrate specificity and activity of CAD can result in significant changes in overall composition and amount of lignin. Our in-depth characterization of two major CAD isoforms, SbCAD2 (Brown midrib 6 [bmr6]) and SbCAD4, in lignifying tissues of sorghum ( Sorghum bicolor ), a strategic plant for generating renewable chemicals and fuels, indicates their similarity in both structure and activity to Arabidopsis ( Arabidopsis thaliana ) CAD5 and Populus tremuloides sinapyl alcohol dehydrogenase, respectively. This first crystal structure of a monocot CAD combined with enzyme kinetic data and a catalytic model supported by site-directed mutagenesis allows full comparison with dicot CADs and elucidates the potential signature sequence for their substrate specificity and activity. The L119W/G301F-SbCAD4 double mutant displayed its substrate preference in the order coniferaldehyde > p -coumaraldehyde > sinapaldehyde, with higher catalytic efficiency than that of both wild-type SbCAD4 and SbCAD2. As SbCAD4 is the only major CAD isoform in bmr6 mutants, replacing SbCAD4 with L119W/G301F-SbCAD4 in bmr6 plants could produce a phenotype that is more amenable to biomass processing. © 2017 American Society of Plant Biologists. All Rights Reserved.

A CAD System for Hemorrhagic Stroke.

PubMed

Nowinski, Wieslaw L; Qian, Guoyu; Hanley, Daniel F

2014-09-01

Computer-aided detection/diagnosis (CAD) is a key component of routine clinical practice, increasingly used for detection, interpretation, quantification and decision support. Despite a critical need, there is no clinically accepted CAD system for stroke yet. Here we introduce a CAD system for hemorrhagic stroke. This CAD system segments, quantifies, and displays hematoma in 2D/3D, and supports evacuation of hemorrhage by thrombolytic treatment monitoring progression and quantifying clot removal. It supports seven-step workflow: select patient, add a new study, process patient's scans, show segmentation results, plot hematoma volumes, show 3D synchronized time series hematomas, and generate report. The system architecture contains four components: library, tools, application with user interface, and hematoma segmentation algorithm. The tools include a contour editor, 3D surface modeler, 3D volume measure, histogramming, hematoma volume plot, and 3D synchronized time-series hematoma display. The CAD system has been designed and implemented in C++. It has also been employed in the CLEAR and MISTIE phase-III, multicenter clinical trials. This stroke CAD system is potentially useful in research and clinical applications, particularly for clinical trials.

Viewing CAD Drawings on the Internet

ERIC Educational Resources Information Center

Schwendau, Mark

2004-01-01

Computer aided design (CAD) has been producing 3-D models for years. AutoCAD software is frequently used to create sophisticated 3-D models. These CAD files can be exported as 3DS files for import into Autodesk's 3-D Studio Viz. In this program, the user can render and modify the 3-D model before exporting it out as a WRL (world file hyperlinked)…

TRAD or CAD? A Comparison.

ERIC Educational Resources Information Center

Resetarits, Paul J.

1989-01-01

Studies whether traditional drafting equipment (TRAD) or computer aided drafting equipment (CAD) is more effective. Proposes that students using only CAD can learn principles of drafting as well as students using only TRAD. Reports no significant difference either on achievement or attitude. (MVL)

Computing Mass Properties From AutoCAD

NASA Technical Reports Server (NTRS)

Jones, A.

1990-01-01

Mass properties of structures computed from data in drawings. AutoCAD to Mass Properties (ACTOMP) computer program developed to facilitate quick calculations of mass properties of structures containing many simple elements in such complex configurations as trusses or sheet-metal containers. Mathematically modeled in AutoCAD or compatible computer-aided design (CAD) system in minutes by use of three-dimensional elements. Written in Microsoft Quick-Basic (Version 2.0).

Use of CAD Geometry in MDO

NASA Technical Reports Server (NTRS)

Samareh, Jamshid A.

1996-01-01

The purpose of this paper is to discuss the use of Computer-Aided Design (CAD) geometry in a Multi-Disciplinary Design Optimization (MDO) environment. Two techniques are presented to facilitate the use of CAD geometry by different disciplines, such as Computational Fluid Dynamics (CFD) and Computational Structural Mechanics (CSM). One method is to transfer the load from a CFD grid to a CSM grid. The second method is to update the CAD geometry for CSM deflection.

Incorporating CAD Instruction into the Drafting Curriculum.

ERIC Educational Resources Information Center

Yuen, Steve Chi-Yin

1990-01-01

If education is to meet the challenged posed by the U.S. productivity crisis and the large number of computer-assisted design (CAD) workstations forecast as necessary in the future, schools must integrate CAD into the drafting curriculum and become aggressive in providing CAD training. Teachers need to maintain close contact with local industries…

Education and Training Packages for CAD/CAM.

ERIC Educational Resources Information Center

Wright, I. C.

1986-01-01

Discusses educational efforts in the fields of Computer Assisted Design and Manufacturing (CAD/CAM). Describes two educational training initiatives underway in the United Kingdom, one of which is a resource materials package for teachers of CAD/CAM at the undergraduate level, and the other a training course for managers of CAD/CAM systems. (TW)

CAD Skills Increased through Multicultural Design Project

ERIC Educational Resources Information Center

Clemons, Stephanie

2006-01-01

This article discusses how students in a college-entry-level CAD course researched four generations of their family histories and documented cultural and symbolic influences within their family backgrounds. AutoCAD software was then used to manipulate those cultural and symbolic images to create the design for a multicultural area rug. AutoCAD was…

Atmosphere aerosol satellite project Aerosol-UA

NASA Astrophysics Data System (ADS)

Milinevsky, Gennadi; Yatskiv, Yaroslav; Syniavskyi, Ivan; Bovchaliuk, Andrii; Degtyaryov, Oleksandr; Sosonkin, Mikhail; Mishchenko, Michael; Danylevsky, Vassyl; Ivanov, Yury; Oberemok, Yevgeny; Masley, Volodymyr; Rosenbush, Vera; Moskalev, Sergii

2017-04-01

channels of the MSIP are the intensity channels that serve to obtain images in eight spectral wavebands to retrieve the aerosol optical depth. The main feature of the each MSIP channel is the splitting of the image by a special prism-splitter to four images on the same CCD detector. In that way we can simultaneously measure four polarization components at 0°, 45°, 90° and 135° as images in each of three polarization channels. One of the special features of ScanPol/MSIP concept is calibration of the MSIP using ScanPol data in the same field-of-view with 1% expected polarization accuracy. The Aerosol-UA experiment is planned to be launched in 2020 at the new satellite platform YuzhSat developed in the Yuzhnoye Design Office. The GRASP algorithm (Dubovik et al. 2014, doi: 10.1117/2.1201408.005558) is planned for Aerosol-UA data processing and AERONET sun photometers observations for validation. Acknowledgements. The work was partly supported by the Special Complex Program for Space Research 2012-2016 of the National Academy of Sciences of Ukraine, by the project 16BF051-02 of the Taras Shevchenko National University of Kyiv, and by the grant of the State Fund for Fundamental Research, project F73/115-2016.

Structured reporting platform improves CAD-RADS assessment.

PubMed

Szilveszter, Bálint; Kolossváry, Márton; Karády, Júlia; Jermendy, Ádám L; Károlyi, Mihály; Panajotu, Alexisz; Bagyura, Zsolt; Vecsey-Nagy, Milán; Cury, Ricardo C; Leipsic, Jonathon A; Merkely, Béla; Maurovich-Horvat, Pál

2017-11-01

Structured reporting in cardiac imaging is strongly encouraged to improve quality through consistency. The Coronary Artery Disease - Reporting and Data System (CAD-RADS) was recently introduced to facilitate interdisciplinary communication of coronary CT angiography (CTA) results. We aimed to assess the agreement between manual and automated CAD-RADS classification using a structured reporting platform. Five readers prospectively interpreted 500 coronary CT angiographies using a structured reporting platform that automatically calculates the CAD-RADS score based on stenosis and plaque parameters manually entered by the reader. In addition, all readers manually assessed CAD-RADS blinded to the automatically derived results, which was used as the reference standard. We evaluated factors influencing reader performance including CAD-RADS training, clinical load, time of the day and level of expertise. Total agreement between manual and automated classification was 80.2%. Agreement in stenosis categories was 86.7%, whereas the agreement in modifiers was 95.8% for "N", 96.8% for "S", 95.6% for "V" and 99.4% for "G". Agreement for V improved after CAD-RADS training (p = 0.047). Time of the day and clinical load did not influence reader performance (p > 0.05 both). Less experienced readers had a higher total agreement as compared to more experienced readers (87.0% vs 78.0%, respectively; p = 0.011). Even though automated CAD-RADS classification uses data filled in by the readers, it outperforms manual classification by preventing human errors. Structured reporting platforms with automated calculation of the CAD-RADS score might improve data quality and support standardization of clinical decision making. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Investigation of IGES for CAD/CAE data transfer

NASA Technical Reports Server (NTRS)

Zobrist, George W.

1989-01-01

In a CAD/CAE facility there is always the possibility that one may want to transfer the design graphics database from the native system to a non-native system. This may occur because of dissimilar systems within an organization or a new CAD/CAE system is to be purchased. The Initial Graphics Exchange Specification (IGES) was developed in an attempt to solve this scenario. IGES is a neutral database format into which the CAD/CAE native database format can be translated to and from. Translating the native design database format to IGES requires a pre-processor and transling from IGES to the native database format requires a post-processor. IGES is an artifice to represent CAD/CAE product data in a neutral environment to allow interfacing applications, archive the database, interchange of product data between dissimilar CAD/CAE systems, and other applications. The intent here is to present test data on translating design product data from a CAD/CAE system to itself and to translate data initially prepared in IGES format to various native design formats. This information can be utilized in planning potential procurement and developing a design discipline within the CAD/CAE community.

Phylogeny and expression profiling of CAD and CAD-like genes in hybrid Populus (P. deltoides × P. nigra): evidence from herbivore damage for subfunctionalization and functional divergence

PubMed Central

2010-01-01

Background Cinnamyl Alcohol Dehydrogenase (CAD) proteins function in lignin biosynthesis and play a critical role in wood development and plant defense against stresses. Previous phylogenetic studies did not include genes from seedless plants and did not reflect the deep evolutionary history of this gene family. We reanalyzed the phylogeny of CAD and CAD-like genes using a representative dataset including lycophyte and bryophyte sequences. Many CAD/CAD-like genes do not seem to be associated with wood development under normal growth conditions. To gain insight into the functional evolution of CAD/CAD-like genes, we analyzed their expression in Populus plant tissues in response to feeding damage by gypsy moth larvae (Lymantria dispar L.). Expression of CAD/CAD-like genes in Populus tissues (xylem, leaves, and barks) was analyzed in herbivore-treated and non-treated plants by real time quantitative RT-PCR. Results CAD family genes were distributed in three classes based on sequence conservation. All the three classes are represented by seedless as well as seed plants, including the class of bona fide lignin pathway genes. The expression of some CAD/CAD-like genes that are not associated with xylem development were induced following herbivore damage in leaves, while other genes were induced in only bark or xylem tissues. Five of the CAD/CAD-like genes, however, showed a shift in expression from one tissue to another between non-treated and herbivore-treated plants. Systemic expression of the CAD/CAD-like genes was generally suppressed. Conclusions Our results indicated a correlation between the evolution of the CAD gene family and lignin and that the three classes of genes may have evolved in the ancestor of land plants. Our results also suggest that the CAD/CAD-like genes have evolved a diversity of expression profiles and potentially different functions, but that they are nonetheless co-regulated under stress conditions. PMID:20509918

Comprehensive BRL-CAD Primitive Database

DTIC Science & Technology

2015-03-01

are not to be construed as an official Department of the Army position unless so designated by other authorized documents. Citation of...database provides the target describers of BRL–CAD with a representative example of each primitive’s shape and its properties. In addition to the...database was completed, a tool was created to generate primitive shapes automatically. This provides target describers—CAD experts who generate

Machinability of CAD-CAM materials.

PubMed

Chavali, Ramakiran; Nejat, Amir H; Lawson, Nathaniel C

2017-08-01

Although new materials are available for computer-aided design and computer-aided manufacturing (CAD-CAM) fabrication, limited information is available regarding their machinability. The depth of penetration of a milling tool into a material during a timed milling cycle may indicate its machinability. The purpose of this in vitro study was to compare the tool penetration rate for 2 polymer-containing CAD-CAM materials (Lava Ultimate and Enamic) and 2 ceramic-based CAD-CAM materials (e.max CAD and Celtra Duo). The materials were sectioned into 4-mm-thick specimens (n=5/material) and polished with 320-grit SiC paper. Each specimen was loaded into a custom milling apparatus. The apparatus pushed the specimens against a milling tool (E4D Tapered 2016000) rotating at 40 000 RPM with a constant force of 0.98 N. After a 6-minute timed milling cycle, the length of each milling cut was measured with image analysis software under a digital light microscope. Representative specimens and milling tools were examined with scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy. The penetration rate of Lava Ultimate (3.21 ±0.46 mm/min) and Enamic (2.53 ±0.57 mm/min) was significantly greater than that of e.max CAD (1.12 ±0.32 mm/min) or Celtra Duo (0.80 ±0.21 mm/min) materials. SEM observations showed little tool damage, regardless of material type. Residual material was found on the tools used with polymer-containing materials, and wear of the embedding medium was seen on the tools used with the ceramic-based materials. Edge chipping was noted on cuts made in the ceramic-based materials. Lava Ultimate and Enamic have greater machinability and less edge chipping than e.max CAD and Celtra Duo. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

The Challenging Academic Development (CAD) Collective

ERIC Educational Resources Information Center

Peseta, Tai

2005-01-01

This article discusses the Challenging Academic Development (CAD) Collective and describes how it came out of a symposium called "Liminality, identity, and hybridity: On the promise of new conceptual frameworks for theorising academic/faculty development." The CAD Collective is and represents a space where people can open up their…

CAD/CAM produces dentures with improved fit.

PubMed

Steinmassl, Otto; Dumfahrt, Herbert; Grunert, Ingrid; Steinmassl, Patricia-Anca

2018-02-22

Resin polymerisation shrinkage reduces the congruence of the denture base with denture-bearing tissues and thereby decreases the retention of conventionally fabricated dentures. CAD/CAM denture manufacturing is a subtractive process, and polymerisation shrinkage is not an issue anymore. Therefore, CAD/CAM dentures are assumed to show a higher denture base congruence than conventionally fabricated dentures. It has been the aim of this study to test this hypothesis. CAD/CAM dentures provided by four different manufacturers (AvaDent, Merz Dental, Whole You, Wieland/Ivoclar) were generated from ten different master casts. Ten conventional dentures (pack and press, long-term heat polymerisation) made from the same master casts served as control group. The master casts and all denture bases were scanned and matched digitally. The absolute incongruences were measured using a 2-mm mesh. Conventionally fabricated dentures showed a mean deviation of 0.105 mm, SD = 0.019 from the master cast. All CAD/CAM dentures showed lower mean incongruences. From all CAD/CAM dentures, AvaDent Digital Dentures showed the highest congruence with the master cast surface with a mean deviation of 0.058 mm, SD = 0.005. Wieland Digital Dentures showed a mean deviation of 0.068 mm, SD = 0.005, Whole You Nexteeth prostheses showed a mean deviation of 0.074 mm, SD = 0.011 and Baltic Denture System prostheses showed a mean deviation of 0.086 mm, SD = 0.012. CAD/CAM produces dentures with better fit than conventional dentures. The present study explains the clinically observed enhanced retention and lower traumatic ulcer-frequency in CAD/CAM dentures.

RESEARCH AND DESIGN ABOUT VERSATILE 3D-CAD ENGINE FOR CONSTRUCTION

NASA Astrophysics Data System (ADS)

Tanaka, Shigenori; Kubota, Satoshi; Kitagawa, Etsuji; Monobe, Kantaro; Nakamura, Kenji

In the construction field of Japan, it is an important subject to build the environment where 3D-CAD data is used for CALS/EC, information construction, and an improvement in productivity. However, in the construction field, 3D-CAD software does not exist under the present circumstances. Then, in order to support development of domestic 3D-CAD software, it is required to develop a 3D-CAD engine. In this research, in order to familiarize the 3D-CAD software at low cost and quickly and build the environment where the 3D-CAD software is utilizable, investigation for designing a 3D-CAD engine is proposed. The target for investigation are the use scene of 3D-CAD, the seeds which accompany 3D-CAD, a standardization trend, existing products, IT component engineering. Based on results of the investigation, the functional requirements for the 3D-CAD engine for the construction field were concluded.

Potential Retrieval of Aerosol Microphysics From Multistatic Space-Borne Lidar

NASA Astrophysics Data System (ADS)

Levitan, Nathaniel; Gross, Barry; Moshary, Fred; Wu, Yonghua

2018-04-01

HSRL lidars are being considered for deployment to space to retrieve aerosol microphysics. The literature is mostly focused on the monostatic configuration; but, in this paper, we explore whether additional information for the retrieval of microphysics can be obtained by adding a second detector in a bistatic configuration. The information gained from the additional measurements can under certain conditions reduce the ill-posed nature of aerosol microphysics retrieval and reducing the uncertainty in the retrievals.

YAG aerosol lidar

NASA Technical Reports Server (NTRS)

Sullivan, R.

1988-01-01

The Global Atmospheric Backscatter Experiment (GLOBE) Mission, using the NASA DC-8 aircraft platform, is designed to provide the magnitude and statistical distribution of atmospheric backscatter cross section at lidar operating wavelengths. This is a fundamental parameter required for the Doppler lidar proposed to be used on a spacecraft platform for global wind field measurements. The prime measurements will be made by a CO2 lidar instrument in the 9 to 10 micron range. These measurements will be complemented with the Goddard YAG Aerosol Lidar (YAL) data in two wavelengths, 0.532 and 1.06 micron, in the visible and near-infrared. The YAL, is being designed to utilize as much existing hardware, as feasible, to minimize cost and reduce implementation time. The laser, energy monitor, telescope and detector package will be mounted on an optical breadboard. The optical breadboard is mounted through isolation mounts between two low boy racks. The detector package will utilize a photomultiplier tube for the 0.532 micron channel and a silicon avalanche photo detector (APD) for the 1.06 micron channel.

Next Generation CAD/CAM/CAE Systems

NASA Technical Reports Server (NTRS)

Noor, Ahmed K. (Compiler); Malone, John B. (Compiler)

1997-01-01

This document contains presentations from the joint UVA/NASA Workshop on Next Generation CAD/CAM/CAE Systems held at NASA Langley Research Center in Hampton, Virginia on March 18-19, 1997. The presentations focused on current capabilities and future directions of CAD/CAM/CAE systems, aerospace industry projects, and university activities related to simulation-based design. Workshop attendees represented NASA, commercial software developers, the aerospace industry, government labs, and academia. The workshop objectives were to assess the potential of emerging CAD/CAM/CAE technology for use in intelligent simulation-based design and to provide guidelines for focused future research leading to effective use of CAE systems for simulating the entire life cycle of aerospace systems.

Increased exposure to pollutant aerosols under high voltage power lines.

PubMed

Fews, A P; Henshaw, D L; Keitch, P A; Close, J J; Wilding, R J

1999-12-01

To assess increased exposure to airborne pollutants near power lines by investigating theoretically and experimentally the behaviour of 222Rn decay product marker aerosols in the 50 Hz electric field under power lines. The behaviour of aerosols in outdoor air including those carrying 222Rn decay products was modelled theoretically in the presence of an AC field. TASTRAK alpha-particle spectroscopy was used to characterize 218Po and 214Po aerosols outdoors. Sampling points were chosen along a line at right angles up to 200 m from a number of high voltage power (transmission) lines. Each sampling point comprised an arrangement of mutually orthogonal TASTRAK detectors. Exposures were carried out at different power line locations in various weather conditions. The model predicts a two- to three-fold increase in deposition of aerosols on spherical surfaces mimicking the human head under high voltage power lines. Experimental measurements using detectors mounted on grounded metal spheres showed an enhanced deposition of both 218Po and 214Po aerosols. Enhanced 218Po deposition on 400 kV lines ranged from 1.96+/-0.15 to 2.86+/-0.32. Enhanced 214Po deposition on 275 kV and 132 kV lines were 1.43+/-0.07 and 1.11+/-0.21, respectively, where the latter value was not significant. The observations demonstrate a mode of increased exposure to pollutant aerosols under high voltage power lines by increased deposition on the body. The total (indoor + outdoor) 218Po and 214Po dose to the basal layer of facial skin is estimated to be increased by between 1.2 and 2.0 for 10% of time spent outdoors under high voltage power lines.

Simulation of the CRIPT Detector

DTIC Science & Technology

2015-03-01

National Defence, 2015 c© Sa Majesté la Reine (en droit du Canada), telle que réprésentée par le ministre de la Défense nationale, 2015 Abstract The...iron slabs of the spectrometer. The red plates are the panels containing the scintillator bars. 3 3 Monte Carlo Geometry The geometry of the detector is...instead of hollow), • parts were in wrong location (eg. spectrometer iron plates). To fix this, Computer Aided Design ( CAD ) drawings were provided for

Shape optimization and CAD

NASA Technical Reports Server (NTRS)

Rasmussen, John

1990-01-01

Structural optimization has attracted the attention since the days of Galileo. Olhoff and Taylor have produced an excellent overview of the classical research within this field. However, the interest in structural optimization has increased greatly during the last decade due to the advent of reliable general numerical analysis methods and the computer power necessary to use them efficiently. This has created the possibility of developing general numerical systems for shape optimization. Several authors, eg., Esping; Braibant & Fleury; Bennet & Botkin; Botkin, Yang, and Bennet; and Stanton have published practical and successful applications of general optimization systems. Ding and Homlein have produced extensive overviews of available systems. Furthermore, a number of commercial optimization systems based on well-established finite element codes have been introduced. Systems like ANSYS, IDEAS, OASIS, and NISAOPT are widely known examples. In parallel to this development, the technology of computer aided design (CAD) has gained a large influence on the design process of mechanical engineering. The CAD technology has already lived through a rapid development driven by the drastically growing capabilities of digital computers. However, the systems of today are still considered as being only the first generation of a long row of computer integrated manufacturing (CIM) systems. These systems to come will offer an integrated environment for design, analysis, and fabrication of products of almost any character. Thus, the CAD system could be regarded as simply a database for geometrical information equipped with a number of tools with the purpose of helping the user in the design process. Among these tools are facilities for structural analysis and optimization as well as present standard CAD features like drawing, modeling, and visualization tools. The state of the art of structural optimization is that a large amount of mathematical and mechanical techniques are

CAD/CAM/CNC.

ERIC Educational Resources Information Center

Domermuth, Dave; And Others

1996-01-01

Includes "Quick Start CNC (computer numerical control) with a Vacuum Filter and Laminated Plastic" (Domermuth); "School and Industry Cooperate for Mutual Benefit" (Buckler); and "CAD (computer-assisted drafting) Careers--What Professionals Have to Say" (Skinner). (JOW)

Concerns of Hydrothermal Degradation in CAD/CAM Zirconia

PubMed Central

Kim, J.-W.; Covel, N.S.; Guess, P.C.; Rekow, E.D.; Zhang, Y.

2010-01-01

Zirconia-based restorations are widely used in prosthetic dentistry; however, their susceptibility to hydrothermal degradation remains elusive. We hypothesized that CAD/CAM machining and subsequent surface treatments, i.e., grinding and/or grit-blasting, have marked effects on the hydrothermal degradation behavior of Y-TZP. CAD/CAM-machined Y-TZP plates (0.5 mm thick), both with and without subsequent grinding with various grit sizes or grit-blasting with airborne alumina particles, were subjected to accelerated aging tests in a steam autoclave. Results showed that the CAD/CAM-machined surfaces initially exhibited superior hydrothermal degradation resistance, but deteriorated at a faster rate upon prolonged autoclave treatment compared with ground and grit-blasted surfaces. The accelerated hydrothermal degradation of CAD/CAM surfaces is attributed to the CAD/CAM machining damage and the absence of surface compressive stresses in the fully sintered material. Clinical relevance for surface treatments of zirconia frameworks in terms of hydrothermal and structural stabilities is addressed. PMID:19966039

Performance and value of CAD-deficient pine- Final Report

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

Bailian Li; Houmin Chang; Hasan Jameel

2007-02-28

The southern US produces 58% of the nation's timber, much of it grown in intensively managed plantations of genetically improved loblolly pine. One of the fastest-growing loblolly pine selections made by the NCSU-Industry Cooperative Tree Improvement Program, whose progeny are widely planted, is also the only known natural carrier of a rare gene, cadn1. This allele codes for deficiency in an enzyme, cinnamyl alcohol dehydrogenase, which catalyzes the last step in the biosynthesis of lignin precursors. This study is to characterize this candidate gene for marker-assisted selection and deployment in the breeding program. This research will enhance the sustainability ofmore » forest production in the South, where land-use pressures will limit the total area available in the future for intensively managed plantations. Furthermore, this research will provide information to establish higher-value plantation forests with more desirable wood/fiber quality traits. A rare mutant allele (cad-n1) of the cad gene in loblolly pine (Pinus taeda L.) causes a deficiency in the production of cinnamyl alcohol dehydrogenase (CAD). The effects of this allele were examined by comparing wood density and growth traits of cad-n1 heterozygous trees with those of wild-type trees in a 10-year-old open-pollinated family trial growing under two levels of fertilization in Scotland County, North Carolina. In all, 200 trees were sampled with 100 trees for each treatment. Wood density measurements were collected from wood cores at breast height using x-ray densitometry. We found that the substitution of cad-n1 for a wild-type allele (Cad) was associated with a significant effect on wood density. The cad-n1 heterozygotes had a significantly higher wood density (+2.6%) compared to wild-type trees. The higher density was apparently due to the higher percentage of latewood in the heterozygotes. The fertilization effect was highly significant for both growth and wood density traits. While no cad

Writing DNA with GenoCAD.

PubMed

Czar, Michael J; Cai, Yizhi; Peccoud, Jean

2009-07-01

Chemical synthesis of custom DNA made to order calls for software streamlining the design of synthetic DNA sequences. GenoCAD (www.genocad.org) is a free web-based application to design protein expression vectors, artificial gene networks and other genetic constructs composed of multiple functional blocks called genetic parts. By capturing design strategies in grammatical models of DNA sequences, GenoCAD guides the user through the design process. By successively clicking on icons representing structural features or actual genetic parts, complex constructs composed of dozens of functional blocks can be designed in a matter of minutes. GenoCAD automatically derives the construct sequence from its comprehensive libraries of genetic parts. Upon completion of the design process, users can download the sequence for synthesis or further analysis. Users who elect to create a personal account on the system can customize their workspace by creating their own parts libraries, adding new parts to the libraries, or reusing designs to quickly generate sets of related constructs.

Bonding Effectiveness of Luting Composites to Different CAD/CAM Materials.

PubMed

Peumans, Marleen; Valjakova, Emilija Bajraktarova; De Munck, Jan; Mishevska, Cece Bajraktarova; Van Meerbeek, Bart

To evaluate the influence of different surface treatments of six novel CAD/CAM materials on the bonding effectiveness of two luting composites. Six different CAD/CAM materials were tested: four ceramics - Vita Mark II; IPS Empress CAD and IPS e.max CAD; Celtra Duo - one hybrid ceramic, Vita Enamic, and one composite CAD/CAM block, Lava Ultimate. A total of 60 blocks (10 per material) received various mechanical surface treatments: 1. 600-grit SiC paper; 2. sandblasting with 30-μm Al2O3; 3. tribochemical silica coating (CoJet). Subsequent chemical surface treatments involved either no further treatment (control), HF acid etching (HF), silanization (S, or HF acid etching followed by silanization (HF+S). Two specimens with the same surface treatment were bonded together using two dual-curing luting composites: Clearfil Esthetic Cement (self-etching) or Panavia SA Cement (self-adhesive). After 1 week of water storage, the microtensile bond strength of the sectioned microspecimens was measured and the failure mode was evaluated. The bonding performance of the six CAD/CAM materials was significantly influenced by surface treatment (linear mixed models, p < 0.05). The luting cement had a significant influence on bond strength for Celtra Duo and Lava Ultimate (linear mixed models, p < 0.05). Mechanical surface treatment significantly influenced the bond strength for Celtra Duo (p = 0.0117), IPS e.max CAD (p = 0.0115), and Lava Ultimate (p < 0.0001). Different chemical surface treatments resulted in the highest bond strengths for the six CAD/CAM materials: Vita Mark II and IPS Empress CAD: S, HF+S; Celtra Duo: HF, HF+S; IPS e.max CAD: HF+S; Vita Enamic: HF+S, S. For Lava Ultimate, the highest bond strengths were obtained with HF, S, HF+S. Failure analysis showed a relation between bond strength and failure type: more mixed failures were observed with higher bond strengths. Mainly adhesive failures were noticed if no further surface treatment was done. The percentage of

Automation in the Teaching of Descriptive Geometry and CAD. High-Level CAD Templates Using Script Languages

NASA Astrophysics Data System (ADS)

Moreno, R.; Bazán, A. M.

2017-10-01

The main purpose of this work is to study improvements to the learning method of technical drawing and descriptive geometry through exercises with traditional techniques that are usually solved manually by applying automated processes assisted by high-level CAD templates (HLCts). Given that an exercise with traditional procedures can be solved, detailed step by step in technical drawing and descriptive geometry manuals, CAD applications allow us to do the same and generalize it later, incorporating references. Traditional teachings have become obsolete and current curricula have been relegated. However, they can be applied in certain automation processes. The use of geometric references (using variables in script languages) and their incorporation into HLCts allows the automation of drawing processes. Instead of repeatedly creating similar exercises or modifying data in the same exercises, users should be able to use HLCts to generate future modifications of these exercises. This paper introduces the automation process when generating exercises based on CAD script files, aided by parametric geometry calculation tools. The proposed method allows us to design new exercises without user intervention. The integration of CAD, mathematics, and descriptive geometry facilitates their joint learning. Automation in the generation of exercises not only saves time but also increases the quality of the statements and reduces the possibility of human error.

Impacts of Cross-Platform Vicarious Calibration on the Deep Blue Aerosol Retrievals for Moderate Resolution Imaging Spectroradiometer Aboard Terra

NASA Technical Reports Server (NTRS)

Jeong, Myeong-Jae; Hsu, N. Christina; Kwiatkowska, Ewa J.; Franz, Bryan A.; Meister, Gerhard; Salustro, Clare E.

2012-01-01

The retrieval of aerosol properties from spaceborne sensors requires highly accurate and precise radiometric measurements, thus placing stringent requirements on sensor calibration and characterization. For the Terra/Moderate Resolution Imaging Spedroradiometer (MODIS), the characteristics of the detectors of certain bands, particularly band 8 [(B8); 412 nm], have changed significantly over time, leading to increased calibration uncertainty. In this paper, we explore a possibility of utilizing a cross-calibration method developed for characterizing the Terral MODIS detectors in the ocean bands by the National Aeronautics and Space Administration Ocean Biology Processing Group to improve aerosol retrieval over bright land surfaces. We found that the Terra/MODIS B8 reflectance corrected using the cross calibration method resulted in significant improvements for the retrieved aerosol optical thickness when compared with that from the Multi-angle Imaging Spectroradiometer, Aqua/MODIS, and the Aerosol Robotic Network. The method reported in this paper is implemented for the operational processing of the Terra/MODIS Deep Blue aerosol products.

AutoCAD-To-NASTRAN Translator Program

NASA Technical Reports Server (NTRS)

Jones, A.

1989-01-01

Program facilitates creation of finite-element mathematical models from geometric entities. AutoCAD to NASTRAN translator (ACTON) computer program developed to facilitate quick generation of small finite-element mathematical models for use with NASTRAN finite-element modeling program. Reads geometric data of drawing from Data Exchange File (DXF) used in AutoCAD and other PC-based drafting programs. Written in Microsoft Quick-Basic (Version 2.0).

Resin-composite blocks for dental CAD/CAM applications.

PubMed

Ruse, N D; Sadoun, M J

2014-12-01

Advances in digital impression technology and manufacturing processes have led to a dramatic paradigm shift in dentistry and to the widespread use of computer-aided design/computer-aided manufacturing (CAD/CAM) in the fabrication of indirect dental restorations. Research and development in materials suitable for CAD/CAM applications are currently the most active field in dental materials. Two classes of materials are used in the production of CAD/CAM restorations: glass-ceramics/ceramics and resin composites. While glass-ceramics/ceramics have overall superior mechanical and esthetic properties, resin-composite materials may offer significant advantages related to their machinability and intra-oral reparability. This review summarizes recent developments in resin-composite materials for CAD/CAM applications, focusing on both commercial and experimental materials. © International & American Associations for Dental Research.

Comparative in vitro evaluation of CAD/CAM vs conventional provisional crowns.

PubMed

Abdullah, Adil Othman; Tsitrou, Effrosyni A; Pollington, Sarah

2016-01-01

This study compared the marginal gap, internal fit, fracture strength, and mode of fracture of CAD/CAM provisional crowns with that of direct provisional crowns. An upper right first premolar phantom tooth was prepared for full ceramic crown following tooth preparation guidelines. The materials tested were: VITA CAD-Temp®, Polyetheretherketone "PEEK", Telio CAD-Temp, and Protemp™4 (control group). The crowns were divided into four groups (n=10), Group1: VITA CAD-Temp®, Group 2: PEEK, Group 3: Telio CAD-Temp, and Group 4: Protemp™4. Each crown was investigated for marginal and internal fit, fracture strength, and mode of fracture. Statistical analysis was performed using GraphPad Prism software version 6.0. The average marginal gap was: VITA CAD-Temp® 60.61 (±9.99) µm, PEEK 46.75 (±8.26) µm, Telio CAD-Temp 56.10 (±5.65) µm, and Protemp™4 193.07(±35.96) µm (P<0.001). The average internal fit was: VITA CAD-Temp® 124.94 (±22.96) µm, PEEK 113.14 (±23.55) µm, Telio CAD-Temp 110.95 (±11.64) µm, and Protemp™4 143.48(±26.74) µm. The average fracture strength was: VITA CAD-Temp® 361.01 (±21.61) N, PEEK 802.23 (±111.29) N, Telio CAD-Temp 719.24 (±95.17) N, and Protemp™4 416.40 (±69.14) N. One-way ANOVA test showed a statistically significant difference for marginal gap, internal gap, and fracture strength between all groups (p<0.001). However, the mode of fracture showed no differences between the groups (p>0.05). CAD/CAM fabricated provisional crowns demonstrated superior fit and better strength than direct provisional crowns.

Comparative in vitro evaluation of CAD/CAM vs conventional provisional crowns

PubMed Central

ABDULLAH, Adil Othman; TSITROU, Effrosyni A; POLLINGTON, Sarah

2016-01-01

ABSTRACT Objective This study compared the marginal gap, internal fit, fracture strength, and mode of fracture of CAD/CAM provisional crowns with that of direct provisional crowns. Material and Methods An upper right first premolar phantom tooth was prepared for full ceramic crown following tooth preparation guidelines. The materials tested were: VITA CAD-Temp®, Polyetheretherketone “PEEK”, Telio CAD-Temp, and Protemp™4 (control group). The crowns were divided into four groups (n=10), Group1: VITA CAD-Temp®, Group 2: PEEK, Group 3: Telio CAD-Temp, and Group 4: Protemp™4. Each crown was investigated for marginal and internal fit, fracture strength, and mode of fracture. Statistical analysis was performed using GraphPad Prism software version 6.0. Results The average marginal gap was: VITA CAD-Temp® 60.61 (±9.99) µm, PEEK 46.75 (±8.26) µm, Telio CAD-Temp 56.10 (±5.65) µm, and Protemp™4 193.07(±35.96) µm (P<0.001). The average internal fit was: VITA CAD-Temp® 124.94 (±22.96) µm, PEEK 113.14 (±23.55) µm, Telio CAD-Temp 110.95 (±11.64) µm, and Protemp™4 143.48(±26.74) µm. The average fracture strength was: VITA CAD-Temp® 361.01 (±21.61) N, PEEK 802.23 (±111.29) N, Telio CAD-Temp 719.24 (±95.17) N, and Protemp™4 416.40 (±69.14) N. One-way ANOVA test showed a statistically significant difference for marginal gap, internal gap, and fracture strength between all groups (p<0.001). However, the mode of fracture showed no differences between the groups (p>0.05). Conclusions CAD/CAM fabricated provisional crowns demonstrated superior fit and better strength than direct provisional crowns. PMID:27383707

Use of CAD systems in design of Space Station and space robots

NASA Technical Reports Server (NTRS)

Dwivedi, Suren N.; Yadav, P.; Jones, Gary; Travis, Elmer W.

1988-01-01

The evolution of CAD systems is traced. State-of-the-art CAD systems are reviewed and various advanced CAD facilities and supplementing systems being used at NASA-Goddard are described. CAD hardware, computer software, and protocols are detailed.

Fracture strength testing of crowns made of CAD/CAM composite resins.

PubMed

Okada, Ryota; Asakura, Masaki; Ando, Akihiro; Kumano, Hirokazu; Ban, Seiji; Kawai, Tatsushi; Takebe, Jun

2018-03-28

The purpose of this study was to ascertain whether computer aided design/computer aided manufacturing (CAD/CAM) composite resin crowns have sufficient strength to withstand the bite force of the molar teeth. The null hypothesis was that the fracture strength of CAD/CAM composite resin crowns is lower than the average maximum bite force of the molar tooth. The crowns, which shape is the right maxillary first molar, were fabricated using four CAD/CAM blanks made of composite resins (Block HC: HC, KZR-CAD HR: HR, KZR-CAD HR2: HR2, Avencia Block: AVE) and one CAD/CAM blank made of lithium disilicate glass-ceramic (IPS e.max CAD: IPS), which was used as a control. Fracture strength of fabricated crowns bonded to metal abutment and biaxial flexural strength of the materials were evaluated. The results of fracture strength test and biaxial flexural strength test showed different tendencies. The fracture strength of CAD/CAM composite resin crowns except HC ranged from 3.3kN to 3.9kN, and was similar to that of IPS (3.3kN). In contrast, biaxial flexural strength of CAD/CAM composite resins ranged from 175MPa to 247MPa, and was significantly lower than that of IPS (360MPa). All CAD/CAM composite resin crowns studied presented about 3-4 times higher fracture strength than the average maximum bite force of the molar tooth (700-900N), which result leads to the conclusion that CAD/CAM composite resin crowns would have sufficient strength to withstand the bite force of the molar teeth. Copyright © 2017 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

A CAD (Classroom Assessment Design) of a Computer Programming Course

ERIC Educational Resources Information Center

Hawi, Nazir S.

2012-01-01

This paper presents a CAD (classroom assessment design) of an entry-level undergraduate computer programming course "Computer Programming I". CAD has been the product of a long experience in teaching computer programming courses including teaching "Computer Programming I" 22 times. Each semester, CAD is evaluated and modified…

CAD-centric Computation Management System for a Virtual TBM

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

Ramakanth Munipalli; K.Y. Szema; P.Y. Huang

HyPerComp Inc. in research collaboration with TEXCEL has set out to build a Virtual Test Blanket Module (VTBM) computational system to address the need in contemporary fusion research for simulating the integrated behavior of the blanket, divertor and plasma facing components in a fusion environment. Physical phenomena to be considered in a VTBM will include fluid flow, heat transfer, mass transfer, neutronics, structural mechanics and electromagnetics. We seek to integrate well established (third-party) simulation software in various disciplines mentioned above. The integrated modeling process will enable user groups to interoperate using a common modeling platform at various stages of themore » analysis. Since CAD is at the core of the simulation (as opposed to computational meshes which are different for each problem,) VTBM will have a well developed CAD interface, governing CAD model editing, cleanup, parameter extraction, model deformation (based on simulation,) CAD-based data interpolation. In Phase-I, we built the CAD-hub of the proposed VTBM and demonstrated its use in modeling a liquid breeder blanket module with coupled MHD and structural mechanics using HIMAG and ANSYS. A complete graphical user interface of the VTBM was created, which will form the foundation of any future development. Conservative data interpolation via CAD (as opposed to mesh-based transfer), the regeneration of CAD models based upon computed deflections, are among the other highlights of phase-I activity.« less

Turnkey CAD/CAM systems' integration with IPAD systems

NASA Technical Reports Server (NTRS)

Blauth, R. E.

1980-01-01

Today's commercially available turnkey CAD/CAM systems provide a highly interactive environment, and support many specialized application functions for the design/drafting/manufacturing process. This paper presents an overview of several aerospace companies which have successfully integrated turnkey CAD/CAM systems with their own company wide engineering and manufacturing systems. It also includes a vendor's view of the benefits as well as the disadvantages of such integration efforts. Specific emphasis is placed upon the selection of standards for representing geometric engineering data and for communicating such information between different CAD/CAM systems.

A new CAD approach for improving efficacy of cancer screening

NASA Astrophysics Data System (ADS)

Zheng, Bin; Qian, Wei; Li, Lihua; Pu, Jiantao; Kang, Yan; Lure, Fleming; Tan, Maxine; Qiu, Yuchen

2015-03-01

Since performance and clinical utility of current computer-aided detection (CAD) schemes of detecting and classifying soft tissue lesions (e.g., breast masses and lung nodules) is not satisfactory, many researchers in CAD field call for new CAD research ideas and approaches. The purpose of presenting this opinion paper is to share our vision and stimulate more discussions of how to overcome or compensate the limitation of current lesion-detection based CAD schemes in the CAD research community. Since based on our observation that analyzing global image information plays an important role in radiologists' decision making, we hypothesized that using the targeted quantitative image features computed from global images could also provide highly discriminatory power, which are supplementary to the lesion-based information. To test our hypothesis, we recently performed a number of independent studies. Based on our published preliminary study results, we demonstrated that global mammographic image features and background parenchymal enhancement of breast MR images carried useful information to (1) predict near-term breast cancer risk based on negative screening mammograms, (2) distinguish between true- and false-positive recalls in mammography screening examinations, and (3) classify between malignant and benign breast MR examinations. The global case-based CAD scheme only warns a risk level of the cases without cueing a large number of false-positive lesions. It can also be applied to guide lesion-based CAD cueing to reduce false-positives but enhance clinically relevant true-positive cueing. However, before such a new CAD approach is clinically acceptable, more work is needed to optimize not only the scheme performance but also how to integrate with lesion-based CAD schemes in the clinical practice.

Field Studies of Broadband Aerosol Optical Extinction in the Ultraviolet Spectral Region

NASA Astrophysics Data System (ADS)

Washenfelder, R. A.; Attwood, A.; Brock, C. A.; Brown, S. S.

2013-12-01

Aerosols influence the Earth's radiative budget by scattering and absorbing incoming solar radiation. The optical properties of aerosols vary as a function of wavelength, but few measurements have reported the wavelength dependence of aerosol extinction cross sections and complex refractive indices. In the case of brown carbon, its wavelength-dependent absorption in the ultraviolet spectral region has been suggested as an important component of aerosol radiative forcing. We describe a new field instrument to measure aerosol optical extinction as a function of wavelength, using cavity enhanced spectroscopy with a broadband light source. The instrument consists of two broadband channels which span the 360-390 and 385-420 nm spectral regions using two light emitting diodes (LED) and a grating spectrometer with charge-coupled device (CCD) detector. We deployed this instrument during the Fire Lab at Missoula Experiment during Fall 2012 to measure biomass burning aerosol, and again during the Southern Oxidant and Aerosol Study in summer 2013 to measure organic aerosol in the Southeastern U.S. In both field experiments, we determined aerosol optical extinction as a function of wavelength and can interpret this together with size distribution and composition measurements to characterize the aerosol optical properties and radiative forcing.

Chairside CAD/CAM materials. Part 2: Flexural strength testing.

PubMed

Wendler, Michael; Belli, Renan; Petschelt, Anselm; Mevec, Daniel; Harrer, Walter; Lube, Tanja; Danzer, Robert; Lohbauer, Ulrich

2017-01-01

Strength is one of the preferred parameters used in dentistry for determining clinical indication of dental restoratives. However, small dimensions of CAD/CAM blocks limit reliable measurements with standardized uniaxial bending tests. The objective of this study was to introduce the ball-on-three-ball (B3B) biaxial strength test for dental for small CAD/CAM block in the context of the size effect on strength predicted by the Weibull theory. Eight representative chairside CAD/CAM materials ranging from polycrystalline zirconia (e.max ZirCAD, Ivoclar-Vivadent), reinforced glasses (Vitablocs Mark II, VITA; Empress CAD, Ivoclar-Vivadent) and glass-ceramics (e.max CAD, Ivoclar-Vivadent; Suprinity, VITA; Celtra Duo, Dentsply) to hybrid materials (Enamic, VITA; Lava Ultimate, 3M ESPE) have been selected. Specimens were prepared with highly polished surfaces in rectangular plate (12×12×1.2mm 3 ) or round disc (Ø=12mm, thickness=1.2mm) geometries. Specimens were tested using the B3B assembly and the biaxial strength was determined using calculations derived from finite element analyses of the respective stress fields. Size effects on strength were determined based on results from 4-point-bending specimens. A good agreement was found between the biaxial strength results for the different geometries (plates vs. discs) using the B3B test. Strength values ranged from 110.9MPa (Vitablocs Mark II) to 1303.21MPa (e.max ZirCAD). The strength dependency on specimen size was demonstrated through the calculated effective volume/surface. The B3B test has shown to be a reliable and simple method for determining the biaxial strength restorative materials supplied as small CAD/CAM blocks. A flexible solution was made available for the B3B test in the rectangular plate geometry. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Aerosol mass spectrometry systems and methods

DOEpatents

Fergenson, David P.; Gard, Eric E.

2013-08-20

A system according to one embodiment includes a particle accelerator that directs a succession of polydisperse aerosol particles along a predetermined particle path; multiple tracking lasers for generating beams of light across the particle path; an optical detector positioned adjacent the particle path for detecting impingement of the beams of light on individual particles; a desorption laser for generating a beam of desorbing light across the particle path about coaxial with a beam of light produced by one of the tracking lasers; and a controller, responsive to detection of a signal produced by the optical detector, that controls the desorption laser to generate the beam of desorbing light. Additional systems and methods are also disclosed.

Making a Case for CAD in the Curriculum.

ERIC Educational Resources Information Center

Threlfall, K. Denise

1995-01-01

Computer-assisted design (CAD) technology is transforming the apparel industry. Students of fashion merchandising and clothing design must be prepared on state-of-the-art equipment. ApparelCAD software is one example of courseware for instruction in pattern design and production. (SK)

CAD-RADS - a new clinical decision support tool for coronary computed tomography angiography.

PubMed

Foldyna, Borek; Szilveszter, Bálint; Scholtz, Jan-Erik; Banerji, Dahlia; Maurovich-Horvat, Pál; Hoffmann, Udo

2018-04-01

Coronary computed tomography angiography (CTA) has been established as an accurate method to non-invasively assess coronary artery disease (CAD). The proposed 'Coronary Artery Disease Reporting and Data System' (CAD-RADS) may enable standardised reporting of the broad spectrum of coronary CTA findings related to the presence, extent and composition of coronary atherosclerosis. The CAD-RADS classification is a comprehensive tool for summarising findings on a per-patient-basis dependent on the highest-grade coronary artery lesion, ranging from CAD-RADS 0 (absence of CAD) to CAD-RADS 5 (total occlusion of a coronary artery). In addition, it provides suggestions for clinical management for each classification, including further testing and therapeutic options. Despite some limitations, CAD-RADS may facilitate improved communication between imagers and patient caregivers. As such, CAD-RADS may enable a more efficient use of coronary CTA leading to more accurate utilisation of invasive coronary angiograms. Furthermore, widespread use of CAD-RADS may facilitate registry-based research of diagnostic and prognostic aspects of CTA. • CAD-RADS is a tool for standardising coronary CTA reports. • CAD-RADS includes clinical treatment recommendations based on CTA findings. • CAD-RADS has the potential to reduce variability of CTA reports.

21 CFR 872.3661 - Optical Impression Systems for CAD/CAM.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Optical Impression Systems for CAD/CAM. 872.3661... (CAD/CAM) is a device used to record the topographical characteristics of teeth, dental impressions, or... Design and Manufacturing (CAD/CAM) of Dental Restorations; Guidance for Industry and FDA.” For the...

21 CFR 872.3661 - Optical Impression Systems for CAD/CAM.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Optical Impression Systems for CAD/CAM. 872.3661... (CAD/CAM) is a device used to record the topographical characteristics of teeth, dental impressions, or... Design and Manufacturing (CAD/CAM) of Dental Restorations; Guidance for Industry and FDA.” For the...

21 CFR 872.3661 - Optical Impression Systems for CAD/CAM.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Optical Impression Systems for CAD/CAM. 872.3661... (CAD/CAM) is a device used to record the topographical characteristics of teeth, dental impressions, or... Design and Manufacturing (CAD/CAM) of Dental Restorations; Guidance for Industry and FDA.” For the...

DeviceEditor visual biological CAD canvas

PubMed Central

2012-01-01

Background Biological Computer Aided Design (bioCAD) assists the de novo design and selection of existing genetic components to achieve a desired biological activity, as part of an integrated design-build-test cycle. To meet the emerging needs of Synthetic Biology, bioCAD tools must address the increasing prevalence of combinatorial library design, design rule specification, and scar-less multi-part DNA assembly. Results We report the development and deployment of web-based bioCAD software, DeviceEditor, which provides a graphical design environment that mimics the intuitive visual whiteboard design process practiced in biological laboratories. The key innovations of DeviceEditor include visual combinatorial library design, direct integration with scar-less multi-part DNA assembly design automation, and a graphical user interface for the creation and modification of design specification rules. We demonstrate how biological designs are rendered on the DeviceEditor canvas, and we present effective visualizations of genetic component ordering and combinatorial variations within complex designs. Conclusions DeviceEditor liberates researchers from DNA base-pair manipulation, and enables users to create successful prototypes using standardized, functional, and visual abstractions. Open and documented software interfaces support further integration of DeviceEditor with other bioCAD tools and software platforms. DeviceEditor saves researcher time and institutional resources through correct-by-construction design, the automation of tedious tasks, design reuse, and the minimization of DNA assembly costs. PMID:22373390

The application of CAD / CAM technology in Dentistry

NASA Astrophysics Data System (ADS)

Susic, I.; Travar, M.; Susic, M.

2017-05-01

Information and communication technologies have found their application in the healthcare sector, including the frameworks of modern dentistry. CAD / CAM application in dentistry is the process by which is attained finished dental restoration through fine milling process of ready ceramic blocks. CAD / CAM is an acronym of english words Computer-Aided-Design (CAD) / Computer-Aided-Manufacture (CAM), respectively dental computer aided design and computer aided manufacture of inlays, onlays, crowns and bridges. CAD / CAM technology essentially allows you to create a two-dimensional and three-dimensional models and their materialization by numerical controlled machines. In order to operate more efficiently, reduce costs, increase user/patient satisfaction and ultimately achieve profits, many dental offices in the world have their attention focused on implementation of modern IT solutions in everyday practice. In addition to the specialized clinic management software, inventory control, etc., or hardware such as the use of lasers in cosmetic dentistry or intraoral scanning, recently the importance is given to the application of CAD / CAM technology in the field of prosthetic. After the removal of pathologically altered tooth structure, it is necessary to achieve restoration that will be most similar to the anatomy of a natural tooth. Applying CAD / CAM technology on applicable ceramic blocks it can be obtained very quick, but also very accurate restoration, in the forms of inlays, onlays, bridges and crowns. The paper presents the advantages of using this technology as well as satisfaction of the patients and dentists by using systems as: Cercon, Celay, Cerec, Lava, Everest, which represent imperative of modern dentistry in creating fixed dental restorations.

Broadband Measurement of Aerosol Extinction in the Visible Range

NASA Astrophysics Data System (ADS)

He, Quanfu; Bluvshtein, Nir; Segev, Lior; Flores, Michel; Rudich, Yinon; Washenfelder, Rebecca; Brown, Steven

2017-04-01

Atmospheric aerosols influence the Earth's radiative budget directly by scattering and absorbing incoming solar radiation. Aerosol direct forcing remains one of the largest uncertainties in quantifying the role that aerosols play in the Earth's radiative budget. The optical properties of aerosols vary as a function of wavelength, but few measurements reported the wavelength dependence of aerosol extinction cross section and complex refractive indices, particularly in the blue and visible spectral range. There is also currently a large gap in our knowledge of how the optical properties evolve as a function of atmospheric aging in the visible spectrum. In this study, we constructed a new and novel laboratory instrument to measure aerosol extinction as a function of wavelength, using cavity enhanced spectroscopy with a white light source. This broadband cavity enhanced spectroscopy (BBCES) covers the 395-700 nm spectral region using a broadband light source and a grating spectrometer with charge-coupled device detector (CCD). We evaluated this BBCES by measuring extinction cross section for aerosols that are pure scattering, slightly absorbing and strongly absorbing atomized from standard materials. We also retrieved the refractive indices from the measured extinction cross sections. Secondary organic aerosols from biogenic and anthropogenic precursors were "aged" to differential time scales (1 to 10 days) in an Oxidation Flow Reactor (OFR) under the combined influence of OH, O3 and UV light. The new BBCES was used to online measure the extinction cross sections of the SOA. This talk will provide a comprehensive understanding of aerosol optical properties alerting during aging process in the 395 - 700 nm spectrum.

CAD/CAM approach to improving industry productivity gathers momentum

NASA Technical Reports Server (NTRS)

Fulton, R. E.

1982-01-01

Recent results and planning for the NASA/industry Integrated Programs for Aerospace-Vehicle Design (IPAD) program for improving productivity with CAD/CAM methods are outlined. The industrial group work is being mainly done by Boeing, and progress has been made in defining the designer work environment, developing requirements and a preliminary design for a future CAD/CAM system, and developing CAD/CAM technology. The work environment was defined by conducting a detailed study of a reference design process, and key software elements for a CAD/CAM system have been defined, specifically for interactive design or experiment control processes. Further work is proceeding on executive, data management, geometry and graphics, and general utility software, and dynamic aspects of the programs being developed are outlined

User productivity as a function of AutoCAD interface design.

PubMed

Mitta, D A; Flores, P L

1995-12-01

Increased operator productivity is a desired outcome of user-CAD interaction scenarios. Two objectives of this research were to (1) define a measure of operator productivity and (2) empirically investigate the potential effects of CAD interface design on operator productivity, where productivity is defined as the percentage of a drawing session correctly completed per unit time. Here, AutoCAD provides the CAD environment of interest. Productivity with respect to two AutoCAD interface designs (menu, template) and three task types (draw, dimension, display) was investigated. Analysis of user productivity data revealed significantly higher productivity under the menu interface condition than under the template interface condition. A significant effect of task type was also discovered, where user productivity under display tasks was higher than productivity under the draw and dimension tasks. Implications of these results are presented.

Analog Computer-Aided Detection (CAD) information can be more effective than binary marks.

PubMed

Cunningham, Corbin A; Drew, Trafton; Wolfe, Jeremy M

2017-02-01

In socially important visual search tasks, such as baggage screening and diagnostic radiology, experts miss more targets than is desirable. Computer-aided detection (CAD) programs have been developed specifically to improve performance in these professional search tasks. For example, in breast cancer screening, many CAD systems are capable of detecting approximately 90% of breast cancer, with approximately 0.5 false-positive detections per image. Nevertheless, benefits of CAD in clinical settings tend to be small (Birdwell, 2009) or even absent (Meziane et al., 2011; Philpotts, 2009). The marks made by a CAD system can be "binary," giving the same signal to any location where the signal is above some threshold. Alternatively, a CAD system presents an analog signal that reflects strength of the signal at a location. In the experiments reported, we compare analog and binary CAD presentations using nonexpert observers and artificial stimuli defined by two noisy signals: a visible color signal and an "invisible" signal that informed our simulated CAD system. We found that analog CAD generally yielded better overall performance than binary CAD. The analog benefit is similar at high and low target prevalence. Our data suggest that the form of the CAD signal can directly influence performance. Analog CAD may allow the computer to be more helpful to the searcher.

An Evaluation of Internet-Based CAD Collaboration Tools

ERIC Educational Resources Information Center

Smith, Shana Shiang-Fong

2004-01-01

Due to the now widespread use of the Internet, most companies now require computer aided design (CAD) tools that support distributed collaborative design on the Internet. Such CAD tools should enable designers to share product models, as well as related data, from geographically distant locations. However, integrated collaborative design…

CAD-model-based vision for space applications

NASA Technical Reports Server (NTRS)

Shapiro, Linda G.

1988-01-01

A pose acquisition system operating in space must be able to perform well in a variety of different applications including automated guidance and inspections tasks with many different, but known objects. Since the space station is being designed with automation in mind, there will be CAD models of all the objects, including the station itself. The construction of vision models and procedures directly from the CAD models is the goal of this project. The system that is being designed and implementing must convert CAD models to vision models, predict visible features from a given view point from the vision models, construct view classes representing views of the objects, and use the view class model thus derived to rapidly determine the pose of the object from single images and/or stereo pairs.

Analog Computer-Aided Detection (CAD) information can be more effective than binary marks

PubMed Central

Cunningham, Corbin A.; Drew, Trafton; Wolfe, Jeremy M.

2017-01-01

In socially important visual search tasks such as baggage screening and diagnostic radiology, experts miss more targets than is desirable. Computer Aided Detection (CAD) programs have been developed specifically to help improve performance in these professional search tasks. For example, in breast cancer screening, many CAD systems are capable of detecting approximately 90% of breast cancer, with approximately 0.5 false positive detections per image. Nevertheless, benefits of CAD in clinical settings tend to be small (Birdwell, 2009) or even absent (Meziane et al., 2011; Philpotts, 2009). The marks made by a CAD system can be “Binary”, giving the same signal to any location where the signal is above some threshold. Alternatively, a CAD system present an Analog signal that reflected strength of the signal at a location. In the experiments reported here, we compare analog and binary CAD presentations using non-expert observers and artificial stimuli defined by two noisy signals: a visible color signal and an "invisible" signal that informed our simulated CAD system. We found that analog CAD generally yielded better overall performance than binary CAD. The analog benefit is similar at high and low target prevalence. Our data suggest that the form of the CAD signal can directly influence performance. Analog CAD may allow the computer to be more helpful to the searcher. PMID:27928658

Rationale for the Use of CAD/CAM Technology in Implant Prosthodontics

PubMed Central

Abduo, Jaafar; Lyons, Karl

2013-01-01

Despite the predictable longevity of implant prosthesis, there is an ongoing interest to continue to improve implant prosthodontic treatment and outcomes. One of the developments is the application of computer-aided design and computer-aided manufacturing (CAD/CAM) to produce implant abutments and frameworks from metal or ceramic materials. The aim of this narrative review is to critically evaluate the rationale of CAD/CAM utilization for implant prosthodontics. To date, CAD/CAM allows simplified production of precise and durable implant components. The precision of fit has been proven in several laboratory experiments and has been attributed to the design of implants. Milling also facilitates component fabrication from durable and aesthetic materials. With further development, it is expected that the CAD/CAM protocol will be further simplified. Although compelling clinical evidence supporting the superiority of CAD/CAM implant restorations is still lacking, it is envisioned that CAD/CAM may become the main stream for implant component fabrication. PMID:23690778

Teach CAD and Measuring Skills through Reverse Engineering

ERIC Educational Resources Information Center

Board, Keith

2012-01-01

This article describes a reverse engineering activity that gives students hands-on, minds-on experience with measuring tools, machine parts, and CAD. The author developed this activity to give students an abundance of practical experience with measuring tools. Equally important, it provides a good interface between the virtual world of CAD 3D…

Evaluating the Learning Process of Mechanical CAD Students

ERIC Educational Resources Information Center

Hamade, R. F.; Artail, H. A.; Jaber, M. Y.

2007-01-01

There is little theoretical or experimental research on how beginner-level trainees learn CAD skills in formal training sessions. This work presents findings on how trainees develop their skills in utilizing a solid mechanical CAD tool (Pro/Engineer version 2000i[squared] and later version Wildfire). Exercises at the beginner and intermediate…

Alkali metal ionization detector

DOEpatents

Bauerle, James E.; Reed, William H.; Berkey, Edgar

1978-01-01

Variations in the conventional filament and collector electrodes of an alkali metal ionization detector, including the substitution of helical electrode configurations for either the conventional wire filament or flat plate collector; or, the substitution of a plurality of discrete filament electrodes providing an in situ capability for transferring from an operationally defective filament electrode to a previously unused filament electrode without removing the alkali metal ionization detector from the monitored environment. In particular, the helical collector arrangement which is coaxially disposed about the filament electrode, i.e. the thermal ionizer, provides an improved collection of positive ions developed by the filament electrode. The helical filament design, on the other hand, provides the advantage of an increased surface area for ionization of alkali metal-bearing species in a monitored gas environment as well as providing a relatively strong electric field for collecting the ions at the collector electrode about which the helical filament electrode is coaxially positioned. Alternatively, both the filament and collector electrodes can be helical. Furthermore, the operation of the conventional alkali metal ionization detector as a leak detector can be simplified as to cost and complexity, by operating the detector at a reduced collector potential while maintaining the sensitivity of the alkali metal ionization detector adequate for the relatively low concentration of alkali vapor and aerosol typically encountered in leak detection applications.

The threshold sensitivity of the molecular condensation nuclei detector

NASA Astrophysics Data System (ADS)

Kuptsov, Vladimir D.; Katelevsky, Vadim Y.; Valyukhov, Vladimir P.

2015-05-01

Molecular condensation nuclei (MCN) method is used in production engineering and process monitoring and relates to optical metrology methods of measuring the concentrations of various contaminants in the environment. Ultra high sensitivity of MCN method to a class of substances is determined by measuring the optical scattering aerosol particles, at the centers of which are located the detectable impurities molecules. This article investigates the influence of MCN manifestations coefficient (ratio of the concentration of aerosol particles to the concentration of molecules detectable impurities) on the sensitivity of the MCN detector. The MCN method is based on the application of various physicochemical processes to the flow of a gas containing impurities. As a result of these processes aerosol particle that are about 106 times larger than the original molecule of the impurity are produced. The ability of the aerosol particle to scatter incident light also increases ~1014 ÷1016 times compared with the original molecule and the aerosol particle with the molecule of the impurity in the center is easily detected by light scattering inside a photometer. By measuring of the light scattering intensity is determined concentration of chemical impurities in the air. An application nephelometric optical metrology scheme of light scattering by aerosol particles ensures stable operation of reliable and flexible measuring systems. Light scattering by aerosol particles is calculated on the basis of the Mie's theory as aerosol particle sizes comparable to the wavelength of the optical radiation. The experimental results are shown for detectable impurities of metal carbonyls. Gas analyzers based on the MCN method find application in industries with the possibility of highly toxic emissions into the atmosphere (carbonyl technology of metal coatings and products, destruction of chemical weapons, etc.), during storage and transportation of toxic substances, as well as in the

Computed-aided diagnosis (CAD) in the detection of breast cancer.

PubMed

Dromain, C; Boyer, B; Ferré, R; Canale, S; Delaloge, S; Balleyguier, C

2013-03-01

Computer-aided detection (CAD) systems have been developed for interpretation to improve mammographic detection of breast cancer at screening by reducing the number of false-negative interpretation that can be caused by subtle findings, radiologist distraction and complex architecture. They use a digitized mammographic image that can be obtained from both screen-film mammography and full field digital mammography. Its performance in breast cancer detection is dependent on the performance of the CAD itself, the population to which it is applied and the radiologists who use it. There is a clear benefit to the use of CAD in less experienced radiologist and in detecting breast carcinomas presenting as microcalcifications. This review gives a detailed description CAD systems used in mammography and their performance in assistance of reading in screening mammography and as an alternative to double reading. Other CAD systems developed for MRI and ultrasound are also presented and discussed. Copyright © 2012. Published by Elsevier Ireland Ltd.

CAD/CAM: Practical and Persuasive in Canadian Schools

ERIC Educational Resources Information Center

Willms, Ed

2007-01-01

Chances are that many high school students would not know how to use drafting instruments, but some might want to gain competence in computer-assisted design (CAD) and possibly computer-assisted manufacturing (CAM). These students are often attracted to tech courses by the availability of CAD/CAM instructions, and many go on to impress employers…

Particle and Smoke Detection on ISS for Next Generation Smoke Detectors

NASA Technical Reports Server (NTRS)

Urban, David L.; Ruff, Gary; Yuan, Zeng-guang; Sheredy, William; Funk, Greg

2007-01-01

Rapid fire detection requires the ability to differentiate fire signatures from background conditions and nuisance sources. Proper design of a fire detector requires detailed knowledge of all of these signal sources so that a discriminating detector can be designed. Owing to the absence of microgravity smoke data, all current spacecraft smoke detectors were designed based upon normal-g conditions. The removal of buoyancy reduces the velocities in the high temperature zones in flames, increasing the residence time of smoke particles and consequently allowing longer growth time for the particles. Recent space shuttle experiments confirmed that, in some cases, increased particles sizes are seen in low-gravity and that the relative performance of the ISS (International Space Station) and space-shuttle smoke-detectors changes in low-gravity; however, sufficient particle size information to design new detectors was not obtained. To address this issue, the SAME (Smoke Aerosol Measurement Experiment) experiment is manifested to fly on the ISS in 2007. The SAME experiment will make measurements of the particle size distribution of the smoke particulate from several typical spacecraft materials providing quantitative design data for spacecraft smoke detectors. A precursor experiment (DAFT: Dust Aerosol measurement Feasibility Test) flew recently on the ISS and provided the first measurement of the background smoke particulate levels on the ISS. These background levels are critical to the design of future smoke detectors. The ISS cabin was found to be a very clean environment with particulate levels substantially below the space shuttle and typical ground-based environments.

CAD Integration : new optical design possibilities

NASA Astrophysics Data System (ADS)

Haumonte, Jean-Baptiste; Venturino, Jean-Claude

2005-09-01

The development of optical design and analysis tools in a CAD software can help to optimise the design, size and performance of tomorrow's consumer products. While optics was still held back by software limitations, CAD programs were moving forward in leaps and bounds, improving manufacturing technologies and making it possible to design and produce highly innovative and sophisticated products. The problem was that in the past, 'traditional' optical design programs were only able to simulate spherical and aspherical lenses, meaning that the optical designers were limited to designing systems which were a series of imperfect lenses, each one correcting the last. That is why OPTIS has created the first optical design program to be fully integrated into a CAD program. The technology is available from OPTIS in an integrated SOLIDWORKS or CATIA V5 version. Users of this software can reduce the number of lenses needed in a system. Designers will now have access to complex surfaces such as NURBS meaning they will now be able to define free shape progressive lenses and even improve on optical performances using fewer lenses. This revolutionary technology will allow mechanical designers to work on optical systems and to share information with optical designers for the first time. Previously not possible in a CAD program you may now determine all the optical performances of any optical system, providing first order and third order performances, sequential and non-sequential ray-tracing, wavefront surfaces, point spread function, MTF, spot-diagram, using real optical surfaces and guaranteeing the mechanical precision necessary for an optical system.

Transcriptome-wide identification and characterization of CAD isoforms specific for podophyllotoxin biosynthesis from Podophyllum hexandrum.

PubMed

Bhattacharyya, Dipto; Hazra, Saptarshi; Banerjee, Anindyajit; Datta, Riddhi; Kumar, Deepak; Chakrabarti, Saikat; Chattopadhyay, Sharmila

2016-09-01

Podophyllotoxin (ptox) is a therapeutically important lignan derived from Podophyllum hexandrum and is used as a precursor for the synthesis of anticancer drugs etoposide, teniposide and etopophose. In spite of its enormous economic significance, genomic information on this endangered medicinal herb is scarce. We have performed de novo transcriptome analysis of methyl jasmonate (MeJA)-treated P. hexandrum cell cultures exhibiting enhanced ptox accumulation. The results revealed the maximum up-regulation of several isoforms of cinnamyl alcohol dehydrogenase (CAD). CAD catalyzes the synthesis of coniferyl alcohol and sinapyl alcohol from coniferaldehyde (CAld) and sinapaldehyde respectively. Coniferyl alcohol can produce both lignin and lignan while sinapyl alcohol produces only lignin. To isolate the CAD isoforms favoring ptox, we deduced full length cDNA sequences of four CAD isoforms: PhCAD1, PhCAD2, PhCAD3 and PhCAD4 from the contigs of the transcriptome data. In vitro enzyme assays indicated a higher affinity for CAld over sinapaldehyde for each isoform. In silico molecular docking analyses also suggested that PhCAD3 has a higher binding preference with CAld over sinapaldehyde, followed by PhCAD4, PhCAD2, and PhCAD1, respectively. The transgenic cell cultures overexpressing these isoforms independently revealed that PhCAD3 favored the maximum accumulation of ptox as compared to lignin followed by PhCAD4 and PhCAD2, whereas, PhCAD1 favored both equally. Together, our study reveals transcriptome-wide identification and characterization of ptox specific CAD isoforms from P. hexandrum. It provides a useful resource for future research not only on the ptox biosynthetic pathway but on overall P. hexandrum, an endangered medicinal herb with immense therapeutic importance.

Studying the Relation of Postprandial Triglyceride with Coronary Artery Disease (CAD).

PubMed

Manochehri, Mohammad; Moghadam, Adel Johari

2016-07-27

Coronary artery disease (CAD) is the most common cause of mortality worldwide and determination of contributing factors is essential. This study was conducted to study the relation of postprandial triglyceride as a risk of coronary artery disease in patients with proven CAD by angiography, referred to 502 Hospital of Army in 2015. This observational study conducted as a case-control and contained 80 male participants referred to 502 Hospital of Army. Half of these participants had proven CAD by angiography test and the other ones were healthy as a control group. Fasting serum triglyceride was evaluated in all participants and postprandial TG was checked 4 hours after a standard meal. Obtained data were analyzed by SPSS ver. 13. The results indicated that fasting TG and postprandial TG level were significantly higher in CAD patients (P-value=0.001). It was also shown evaluation of postprandial TG is more sensitive test than fasting TG in case of CAD patients. Our obtained results shown, evaluation of high level of postprandial TG is more reliable than fasting TG for patients whom suffer from CAD.

Biaxial flexural strength of CAD/CAM ceramics.

PubMed

Buso, L; Oliveira-Júnior, O B; Hiroshi Fujiy, F; Leão Lombardo, G H; Ramalho Sarmento, H; Campos, F; Assunção Souza, R O

2011-06-01

Aim of the study was to evaluate the biaxial flexural strength of ceramics processed using the Cerec inLab system. The hypothesis was that the flexural strength would be influenced by the type of ceramic. Ten samples (ISO 6872) of each ceramic (N.=50/n.=10) were made using Cerec inLab (software Cerec 3D) (Ø:15 mm, thickness: 1.2 mm). Three silica-based ceramics (Vita Mark II [VM], ProCad [PC] and e-max CAD ECAD]) and two yttria-stabilized tetragonal-zirconia-polycrystalline ceramics (Y-TZP) (e-max ZirCad [ZrCAD] and Vita In-Ceram 2000 YZ Cubes [VYZ]) were tested. The samples were finished with wet silicone carbide papers up to 1 200-grit and polished in a polishing machine with diamond paste (3 µm). The samples were then submitted to biaxial flexural strength testing in a universal testing machine (EMIC), 1 mm/min. The data (MPa) were analyzed using the Kruskal-Wallis and Dunn (5%) tests. Scanning electronic microscopy (SEM) was performed on a representative sample from each group. The values (median, mean±sd) obtained for the experimental groups were: VM (101.7, 102.1±13.65 MPa), PC (165.2, 160±34.7 MPa), ECAD (437.2, 416.1±50.1 MPa), ZrCAD (804.2, 800.8±64.47 MPa) and VYZ (792.7, 807±100.7 MPa). The type of ceramic influenced the flexural strength values (P=0.0001). The ceramics ECADa, e-max ZrCADa and VYZa presented similar flexural strength values which were significantly higher than the other groups (PCb and VM IIb), which were similar statistically between them (Dunn's test). The hypothesis was accepted. The polycrystalline ceramics (Y-TZP) should be material chosen for make FPDs because of their higher flexural strength values.

Optical properties of CAD-CAM ceramic systems.

PubMed

Della Bona, Alvaro; Nogueira, Audrea D; Pecho, Oscar E

2014-09-01

To evaluate the direct transmittance (T%), translucency, opacity and opalescence of CAD-CAM ceramic systems and the correlation between the translucency parameter (TP) and the contrast ratio (CR). Specimens of shades A1, A2 and A3 (n=5) were fabricated from CAD-CAM ceramic blocks (IPS e.max(®) CAD HT and LT, IPS Empress(®) CAD HT and LT, Paradigm™ C, and VITABLOCS(®) Mark II) and polished to 1.0±0.01mm in thickness. A spectrophotometer (Lambda 20) was used to measure T% on the wavelength range of 400-780nm. Another spectrophotometer (VITA Easyshade(®) Advance) was used to measure the CIE L(*)a(*)b(*) coordinates and the reflectance value (Y) of samples on white and black backgrounds. TP, CR and the opalescence parameter (OP) were calculated. Data were statistically analysed using VAF (variance accounting for) coefficient with Cauchy-Schwarz inequality, one-way ANOVA, Tukey's test, Bonferroni correction and Pearson's correlation. T% of some ceramic systems is dependent on the wavelength. The spectral behaviour showed a slight and constant increase in T% up to approximately 550nm, then some ceramics changed the behaviour as the wavelength gets longer. TP and CR values ranged, respectively, from 16.79 to 21.69 and from 0.52 to 0.64 (r(2)=-0.97). OP values ranged from 3.01 to 7.64. The microstructure of CAD-CAM ceramic systems influenced the optical properties. TP and CR showed a strong correlation for all ceramic systems evaluated. Yet, all ceramics showed some degree of light transmittance. In addition to shade, this study showed that other optical properties influence on the natural appearance of dental ceramics. Copyright © 2014 Elsevier Ltd. All rights reserved.

Aerosol Optical Properties at the Ground Sites during the 2010 CARES Field Campaign

NASA Astrophysics Data System (ADS)

Atkinson, D. B.; Radney, J. G.; Harworth, J. W.

2010-12-01

Preliminary results from the ground sites at the 2010 CARES field campaign (T0 near Sacramento, CA and T1 near Cool, CA) will be presented. A number of aerosol optical properties were measured at high time resolution for the four week study period using custom instruments. The aerosol extinction coefficient was measured at T0 using a cavity ring-down transmissometer (CRDT) at two wavelengths (532 and 1064 nm) and the aerosol scattering coefficient was measured at 532 nm using a Radiance Research M903 nephelometer. At T1, a new CRDT instrument was deployed that measured the extinction coefficient at three wavelengths (355, 532, and 1064 nm) for sub-10 μm (nominal) and sub-2.5 μm aerosols at ambient, elevated, and reduced relative humidity. A new type of custom nephelometer that measures the aerosol scattering coefficient at 532 nm using an array detector was also deployed at T1.

Cam Design Projects in an Advanced CAD Course for Mechanical Engineers

ERIC Educational Resources Information Center

Ault, H. K.

2009-01-01

The objective of this paper is to present applications of solid modeling aimed at modeling of complex geometries such as splines and blended surfaces in advanced CAD courses. These projects, in CAD-based Mechanical Engineering courses, are focused on the use of the CAD system to solve design problems for applications in machine design, namely the…

Incorporation of CAD/CAM Restoration Into Navy Dentistry

DTIC Science & Technology

2017-09-26

CAD/CAM Computer-aided design /Computer-assisted manufacturing CDT Common Dental Terminology DENCAS Dental Common Access System DTF Dental...to reduce avoidable dental emergencies for deployed sailors and marines. Dental Computer-aided design /Computer-assisted manufacturing (CAD/CAM...report will review and evaluate the placement rate by Navy dentists of digitally fabricated in-office ceramic restorations compared to traditional direct

Association of rs662799 in APOA5 with CAD in Chinese Han population.

PubMed

Chen, Hua; Ding, Shifang; Zhou, Mi; Wu, Xiayin; Liu, Xi; Wu, Yun; Liu, Dechao

2018-01-08

CAD (Coronary Artery Disease) is a complex disease that influenced by various environmental and genetic factors. Previous studies have found many single nucleotide polymorphisms (SNPs) associated with the risk of CAD occurrence. However, the results are inconsistent. In this study, we aim to investigate genetic etiology in Chinese Han population by analysis of 7 SNPs in lipid metabolism pathway that previously has been reported to be associated with CAD. A total of 631 samples were used in this study, including 435 CAD cases and 196 normal healthy controls. SNP genotyping were conducted via multiplex PCR amplifying followed by NGS (next-generation sequencing). Rs662799 in APOA5 (Apolipoprotein A5) gene was associated with CAD in Chinese Han population (Odds-ratio = 1.374, P-value = 0.03). No significant association was observed between the rest of SNPs and CAD. Stratified association analysis revealed rs5882 was associated with CAD in non-hypertension group (Odds-ratio = 1.593, P-value = 0.023). Rs1800588 was associated with CAD in smoking group (Odds-ratio = 1.603, P-value = 0.035). The minor allele of rs662799 was the risk factor of CAD occurrences in Chinese Han population.

CAD/CAM interface design of excimer laser micro-processing system

NASA Astrophysics Data System (ADS)

Jing, Liang; Chen, Tao; Zuo, Tiechuan

2005-12-01

Recently CAD/CAM technology has been gradually used in the field of laser processing. The excimer laser micro-processing system just identified G instruction before CAD/CAM interface was designed. However the course of designing a part with G instruction for users is too hard. The efficiency is low and probability of making errors is high. By secondary development technology of AutoCAD with Visual Basic, an application was developed to pick-up each entity's information in graph and convert them to each entity's processing parameters. Also an additional function was added into former controlling software to identify these processing parameters of each entity and realize continue processing of graphic. Based on the above CAD/CAM interface, Users can design a part in AutoCAD instead of using G instruction. The period of designing a part is sharply shortened. This new way of design greatly guarantees the processing parameters of the part is right and exclusive. The processing of complex novel bio-chip has been realized by this new function.

New apparatus of single particle trap system for aerosol visualization

NASA Astrophysics Data System (ADS)

Higashi, Hidenori; Fujioka, Tomomi; Endo, Tetsuo; Kitayama, Chiho; Seto, Takafumi; Otani, Yoshio

2014-08-01

Control of transport and deposition of charged aerosol particles is important in various manufacturing processes. Aerosol visualization is an effective method to directly observe light scattering signal from laser-irradiated single aerosol particle trapped in a visualization cell. New single particle trap system triggered by light scattering pulse signal was developed in this study. The performance of the device was evaluated experimentally. Experimental setup consisted of an aerosol generator, a differential mobility analyzer (DMA), an optical particle counter (OPC) and the single particle trap system. Polystylene latex standard (PSL) particles (0.5, 1.0 and 2.0 μm) were generated and classified according to the charge by the DMA. Singly charged 0.5 and 1.0 μm particles and doubly charged 2.0 μm particles were used as test particles. The single particle trap system was composed of a light scattering signal detector and a visualization cell. When the particle passed through the detector, trigger signal with a given delay time sent to the solenoid valves upstream and downstream of the visualization cell for trapping the particle in the visualization cell. The motion of particle in the visualization cell was monitored by CCD camera and the gravitational settling velocity and the electrostatic migration velocity were measured from the video image. The aerodynamic diameter obtained from the settling velocity was in good agreement with Stokes diameter calculated from the electrostatic migration velocity for individual particles. It was also found that the aerodynamic diameter obtained from the settling velocity was a one-to-one function of the scattered light intensity of individual particles. The applicability of this system will be discussed.

GPU-accelerated depth map generation for X-ray simulations of complex CAD geometries

NASA Astrophysics Data System (ADS)

Grandin, Robert J.; Young, Gavin; Holland, Stephen D.; Krishnamurthy, Adarsh

2018-04-01

Interactive x-ray simulations of complex computer-aided design (CAD) models can provide valuable insights for better interpretation of the defect signatures such as porosity from x-ray CT images. Generating the depth map along a particular direction for the given CAD geometry is the most compute-intensive step in x-ray simulations. We have developed a GPU-accelerated method for real-time generation of depth maps of complex CAD geometries. We preprocess complex components designed using commercial CAD systems using a custom CAD module and convert them into a fine user-defined surface tessellation. Our CAD module can be used by different simulators as well as handle complex geometries, including those that arise from complex castings and composite structures. We then make use of a parallel algorithm that runs on a graphics processing unit (GPU) to convert the finely-tessellated CAD model to a voxelized representation. The voxelized representation can enable heterogeneous modeling of the volume enclosed by the CAD model by assigning heterogeneous material properties in specific regions. The depth maps are generated from this voxelized representation with the help of a GPU-accelerated ray-casting algorithm. The GPU-accelerated ray-casting method enables interactive (> 60 frames-per-second) generation of the depth maps of complex CAD geometries. This enables arbitrarily rotation and slicing of the CAD model, leading to better interpretation of the x-ray images by the user. In addition, the depth maps can be used to aid directly in CT reconstruction algorithms.

Integrating CAD modules in a PACS environment using a wide computing infrastructure.

PubMed

Suárez-Cuenca, Jorge J; Tilve, Amara; López, Ricardo; Ferro, Gonzalo; Quiles, Javier; Souto, Miguel

2017-04-01

The aim of this paper is to describe a project designed to achieve a total integration of different CAD algorithms into the PACS environment by using a wide computing infrastructure. The aim is to build a system for the entire region of Galicia, Spain, to make CAD accessible to multiple hospitals by employing different PACSs and clinical workstations. The new CAD model seeks to connect different devices (CAD systems, acquisition modalities, workstations and PACS) by means of networking based on a platform that will offer different CAD services. This paper describes some aspects related to the health services of the region where the project was developed, CAD algorithms that were either employed or selected for inclusion in the project, and several technical aspects and results. We have built a standard-based platform with which users can request a CAD service and receive the results in their local PACS. The process runs through a web interface that allows sending data to the different CAD services. A DICOM SR object is received with the results of the algorithms stored inside the original study in the proper folder with the original images. As a result, a homogeneous service to the different hospitals of the region will be offered. End users will benefit from a homogeneous workflow and a standardised integration model to request and obtain results from CAD systems in any modality, not dependant on commercial integration models. This new solution will foster the deployment of these technologies in the entire region of Galicia.

Effectiveness and efficiency of a CAD/CAM orthodontic bracket system.

PubMed

Brown, Matthew W; Koroluk, Lorne; Ko, Ching-Chang; Zhang, Kai; Chen, Mengqi; Nguyen, Tung

2015-12-01

The first straight-wire appliance was introduced over 40 years ago to increase the consistency and efficiency of orthodontic treatment. More recently, computer-aided design and computer-aided manufacturing (CAD/CAM) technology has been used to create individualized orthodontic appliances. The purpose of this study was to investigate the clinical effectiveness and efficiency of CAD/CAM customized orthodontic appliances compared with direct and indirect bonded stock orthodontic brackets. This retrospective study included 3 treatment groups: group 1 patients were direct bonded with self-ligating appliances, group 2 patients were indirect bonded with self-ligating appliances, and group 3 patients were indirect bonded with CAD/CAM self-ligating appliances. Complete pretreatment and posttreatment records were obtained for all patients. The American Board of Orthodontics (ABO) Discrepancy Index was used to evaluate the pretreatment records, and the posttreatment outcomes were analyzed using the ABO Cast-Radiograph Evaluation. All data collection and analysis were completed by 1 evaluator. There were no statistically significant differences in the ABO Discrepancy Index or the ABO Cast-Radiograph Evaluation among the groups. Treatment times for the 3 groups were significantly different; the CAD/CAM group was the shortest at 13.8 ± 3.4 months, compared with 21.9 ± 5.0 and 16.9 ± 4.1 months for the direct bonded and indirect bonded groups, respectively. The number of treatment appointments for the CAD/CAM group was significantly fewer than for the direct bonded group. The CAD/CAM orthodontic bracket system evaluated in this study was as effective in treatment outcome measures as were standard brackets bonded both directly and indirectly. The CAD/CAM appliance was more efficient in regard to treatment duration, although the decrease in total archwire appointments was minimal. Further investigation is needed to better quantify the clinical benefits of CAD/CAM orthodontic

Survey of UK dentists regarding the use of CAD/CAM technology.

PubMed

Tran, D; Nesbit, M; Petridis, H

2016-11-18

Statement of the problem Digital workflows (CAD/CAM) have been introduced in dentistry during recent years. No published information exists on dentists' use and reporting of this technology.Purpose The purpose of this survey was to identify the infiltration of CAD/CAM technology in UK dental practices and to investigate the relationship of various demographic factors to the answers regarding use or non-use of this technology.Materials and methods One thousand and thirty-one online surveys were sent to a sample of UK dentists composing of both users and non-users of CAD/CAM. It aimed to reveal information regarding type of usage, materials, perceived benefits, barriers to access, and disadvantages of CAD/CAM dentistry. Statistical analysis was undertaken to test the influence of various demographic variables such as country of work, dentist experience, level of training and type of work (NHS or private).Results The number of completed responses totalled 385. Most of the respondents did not use any part of a digital workflow, and the main barriers to CAD/CAM use were initial costs and a lack of perceived benefit over conventional methods. Dentists delivering mostly private work were most likely to have adopted CAD/CAM technology (P <0.001). Further training also correlated with a greater likelihood of CAD/CAM usage (P <0.001). Most users felt that the technology had led to a change in the use of dental materials, leading to increased use of, for example, zirconia and lithium disilicate. Most users were trained either by companies or self-trained, and a third felt that their training was insufficient. The majority of respondents (89%) felt that CAD/CAM had a big role to play in the future.Conclusion Most of the respondents did not use any part of a digital workflow. However, the majority of surveyed dentists were interested in incorporating CAD/CAM into their workflow, while most believed that it will have a big role in the future. There are still some concerns from

An Instructional Method for the AutoCAD Modeling Environment.

ERIC Educational Resources Information Center

Mohler, James L.

1997-01-01

Presents a command organizer for AutoCAD to aid new uses in operating within the 3-D modeling environment. Addresses analyzing the problem, visualization skills, nonlinear tools, a static view of a dynamic model, the AutoCAD organizer, environment attributes, and control of the environment. Contains 11 references. (JRH)

Computer-aided diagnosis (CAD) for colonoscopy

NASA Astrophysics Data System (ADS)

Gu, Jia; Poirson, Allen

2007-03-01

Colorectal cancer is the second leading cause of cancer deaths, and ranks third for new cancer cases and cancer mortality for both men and women. However, its death rate can be dramatically reduced by appropriate treatment when early detection is available. The purpose of colonoscopy is to identify and assess the severity of lesions, which may be flat or protruding. Due to the subjective nature of the examination, colonoscopic proficiency is highly variable and dependent upon the colonoscopist's knowledge and experience. An automated image processing system providing an objective, rapid, and inexpensive analysis of video from a standard colonoscope could provide a valuable tool for screening and diagnosis. In this paper, we present the design, functionality and preliminary results of its Computer-Aided-Diagnosis (CAD) system for colonoscopy - ColonoCAD TM. ColonoCAD is a complex multi-sensor, multi-data and multi-algorithm image processing system, incorporating data management and visualization, video quality assessment and enhancement, calibration, multiple view based reconstruction, feature extraction and classification. As this is a new field in medical image processing, our hope is that this paper will provide the framework to encourage and facilitate collaboration and discussion between industry, academia, and medical practitioners.

Studying the Relation of Postprandial Triglyceride with Coronary Artery Disease (CAD)

PubMed Central

Manochehri, Mohammad; Moghadam, Adel Johari

2016-01-01

Background: Coronary artery disease (CAD) is the most common cause of mortality worldwide and determination of contributing factors is essential. Aim: This study was conducted to study the relation of postprandial triglyceride as a risk of coronary artery disease in patients with proven CAD by angiography, referred to 502 Hospital of Army in 2015. Material and Methods: This observational study conducted as a case-control and contained 80 male participants referred to 502 Hospital of Army. Half of these participants had proven CAD by angiography test and the other ones were healthy as a control group. Fasting serum triglyceride was evaluated in all participants and postprandial TG was checked 4 hours after a standard meal. Obtained data were analyzed by SPSS ver. 13. Results: The results indicated that fasting TG and postprandial TG level were significantly higher in CAD patients (P-value=0.001). It was also shown evaluation of postprandial TG is more sensitive test than fasting TG in case of CAD patients. Conclusion: Our obtained results shown, evaluation of high level of postprandial TG is more reliable than fasting TG for patients whom suffer from CAD. PMID:27703285

AutoCAD-To-GIFTS Translator Program

NASA Technical Reports Server (NTRS)

Jones, Andrew

1989-01-01

AutoCAD-to-GIFTS translator program, ACTOG, developed to facilitate quick generation of small finite-element models using CASA/GIFTS finite-element modeling program. Reads geometric data of drawing from Data Exchange File (DXF) used in AutoCAD and other PC-based drafting programs. Geometric entities recognized by ACTOG include points, lines, arcs, solids, three-dimensional lines, and three-dimensional faces. From this information, ACTOG creates GIFTS SRC file, which then reads into GIFTS preprocessor BULKM or modified and reads into EDITM to create finite-element model. SRC file used as is or edited for any number of uses. Written in Microsoft Quick-Basic (Version 2.0).

Evaluation of prosthetic valve thrombosis by 64-row multi-detector computed tomography. .

PubMed

Tarzia, Vincenzo; Bortolussi, Giacomo; Rubino, Maurizio; Gallo, Michele; Bottio, Tomaso; Gerosa, Gino

2015-03-01

Multi-detector computed tomography (MDCT), combined with retrospective electrocardiographic gating, permits cardiac imaging with high accuracy. Recent advances in MDCT have seemed to respond adequately to the need for a non-invasive and reliable assessment of the coronary artery lumen. Two patients with prosthetic aortic valves (one bioprosthetic, one mechanical) presented at the authors' institution with dyspnea and syncopal episodes. MDCT was performed to evaluate thrombus characteristics and exclude coronary artery disease (CAD). Based on the MDCT coronary artery assessment, neither patient underwent preoperative invasive coronary angiography, abolishing the risk of any iatrogenic thrombus fragmentation and subsequent embolization. One patient underwent surgical treatment without complications, while medical therapy was successful in the other case. MDCT can be used for the accurate imaging of thrombi on prosthetic aortic valves, and to correctly assess possible CAD.

Deactivation of the E. coli pH stress sensor CadC by cadaverine.

PubMed

Haneburger, Ina; Fritz, Georg; Jurkschat, Nicole; Tetsch, Larissa; Eichinger, Andreas; Skerra, Arne; Gerland, Ulrich; Jung, Kirsten

2012-11-23

At acidic pH and in the presence of lysine, the pH sensor CadC activates transcription of the cadBA operon encoding the lysine/cadaverine antiporter CadB and the lysine decarboxylase CadA. In effect, these proteins contribute to acid stress adaptation in Escherichia coli. cadBA expression is feedback inhibited by cadaverine, and a cadaverine binding site is predicted within the central cavity of the periplasmic domain of CadC on the basis of its crystallographic analysis. Our present study demonstrates that this site only partially accounts for the cadaverine response in vivo. Instead, evidence for a second, pivotal binding site was collected, which overlaps with the pH-responsive patch of amino acids located at the dimer interface of the periplasmic domain. The temporal response of the E. coli Cad module upon acid shock was measured and modeled for two CadC variants with mutated cadaverine binding sites. These studies supported a cascade-like binding and deactivation model for the CadC dimer: binding of cadaverine within the pair of central cavities triggers a conformational transition that exposes two further binding sites at the dimer interface, and the occupation of those stabilizes the inactive conformation. Altogether, these data represent a striking example for the deactivation of a pH sensor. Copyright © 2012 Elsevier Ltd. All rights reserved.

Automated CAD design for sculptured airfoil surfaces

NASA Astrophysics Data System (ADS)

Murphy, S. D.; Yeagley, S. R.

1990-11-01

The design of tightly tolerated sculptured surfaces such as those for airfoils requires a significant design effort in order to machine the tools to create these surfaces. Because of the quantity of numerical data required to describe the airfoil surfaces, a CAD approach is required. Although this approach will result in productivity gains, much larger gains can be achieved by automating the design process. This paper discusses an application which resulted in an eightfold improvement in productivity by automating the design process on the CAD system.

Research on remote sensing image pixel attribute data acquisition method in AutoCAD

NASA Astrophysics Data System (ADS)

Liu, Xiaoyang; Sun, Guangtong; Liu, Jun; Liu, Hui

2013-07-01

The remote sensing image has been widely used in AutoCAD, but AutoCAD lack of the function of remote sensing image processing. In the paper, ObjectARX was used for the secondary development tool, combined with the Image Engine SDK to realize remote sensing image pixel attribute data acquisition in AutoCAD, which provides critical technical support for AutoCAD environment remote sensing image processing algorithms.

WE-E-217A-02: Methodologies for Evaluation of Standalone CAD System Performance.

PubMed

Sahiner, B

2012-06-01

Standalone performance evaluation of a CAD system provides information about the abnormality detection or classification performance of the computerized system alone. Although the performance of the reader with CAD is the final step in CAD system assessment, standalone performance evaluation is an important component for several reasons: First, standalone evaluation informs the reader about the performance level of the CAD system and may have an impact on how the reader uses the system. Second, it provides essential information to the system designer for algorithm optimization during system development. Third, standalone evaluation can provide a detailed description of algorithm performance (e.g., on subgroups of the population) because a larger data set with more samples from different subgroups can be included in standalone studies compared to reader studies. Proper standalone evaluation of a CAD system involves a number of key components, some of which are shared with the assessment of reader performance with CAD. These include (1) selection of a test data set that allows performance assessment with little or no bias and acceptable uncertainty; (2) a reference standard that indicates disease status as well as the location and extent of disease; (3) a clearly defined method for labeling each CAD mark as a true-positive or false-positive; and (4) a properly selected set of metrics to summarize the accuracy of the computer marks and their corresponding scores. In this lecture, we will discuss various approaches for the key components of standalone CAD performance evaluation listed above, and present some of the recommendations and opinions from the AAPM CAD subcommittee on these issues. Learning Objectives 1. Identify basic components and metrics in the assessment of standalone CAD systems 2. Understand how each component may affect the assessed performance 3. Learn about AAPM CAD subcommittee's opinions and recommendations on factors and metrics related to the

Comparative characterization of a novel cad-cam polymer-infiltrated-ceramic-network

PubMed Central

Pascual, Agustín; Camps, Isabel; Grau-Benitez, María

2015-01-01

Background The field of dental ceramics for CAD-CAM is enriched with a new innovative material composition having a porous three-dimensional structure of feldspathic ceramic infiltrated with acrylic resins.The aim of this study is to determine the mechanical properties of Polymer-Infiltrated-Ceramic-Network (PICN) and compare its performance with other ceramics and a nano-ceramic resin available for CAD-CAM systems. Material and Methods In this study a total of five different materials for CAD-CAM were investigated. A polymer-infiltrated ceramic (Vita Enamic), a nano-ceramic resin (Lava Ultimate), a feldspathic ceramic (Mark II), a lithium disilicate ceramic (IPS-e max CAD) and finally a Leucite based ceramic (Empress - CAD). From CAD-CAM blocks, 120 bars (30 for each material cited above) were cut to measure the flexural strength with a three-point-bending test. Strain at failure, fracture stress and Weibull modulus was calculated. Vickers hardness of each material was also measured. Results IPS-EMAX presents mechanical properties significantly better from the other materials studied. Its strain at failure, flexural strength and hardness exhibited significantly higher values in comparison with the others. VITA ENAMIC and LAVA ULTIMATE stand out as the next most resistant materials. Conclusions The flexural strength, elastic modulus similar to a tooth as well as having less hardness than ceramics make PICN materials an option to consider as a restorative material. Key words:Ceramic infiltrated with resin, CAD-CAM, Weibull modulus, flexural strength, micro hardness. PMID:26535096

Evaluation of mechanical and optical behavior of current esthetic dental restorative CAD/CAM composites.

PubMed

Stawarczyk, Bogna; Liebermann, Anja; Eichberger, Marlis; Güth, Jan-Frederik

2015-03-01

To determine the mechanical and optical properties of CAD/CAM composites (LAVA Ultimate, Cerasmart, Shofu Block and two exp. CAD/CAM composites), a hybrid material (VITA Enamic), a leucite (IPS Empress CAD) and a lithium disilicate glass-ceramic (IPS e.max CAD). Three-point flexural strength (FS) was investigated according ISO 6872:2008 (N=240/n=30). Two-body wear (TBW) was analyzed in a chewing simulator (1,200,000 cycles, 50N, 5°/55°C) using human teeth as antagonists (N=120/n=15). Quantitative analysis of wear was carried out with a 3D-scanner and associated matching software. Discoloration rate (DR) after 14 days of storage in cress, curry, red wine, and distilled water (N=384/n=12), and translucency (T) (N=384/n=48) of CAD/CAM materials were measured in a spectrophotometer (400-700nm wavelength). Data were analyzed using two-/one-way ANOVA with Scheffé post-hoc test, Kruskal-Wallis-H test, and linear mixed models (α=0.05). IPS e.max CAD showed the highest FS (p<0.001), followed by LAVA Ultimate; however, not different from the remaining CAD/CAM composites (exception: Shofu Block). The lowest FS showed VITA Enamic and IPS Empress CAD (p<0.001). IPS Empress CAD, VITA Enamic, exp. CAD/CAM composite 2, followed by IPS e.max presented lower material TBW than the remaining CAD/CAM materials (p<0.001). The highest antagonist wear was observed for the tested glass-ceramics and the hybrid material (p<0.001). Storage medium (red wine>curry>cress>distilled water) exerted the highest influence on DR (p<0.001), closely followed by CAD/CAM material. Glass-ceramics showed lower DR than CAD/CAM composites (p<0.001). CAD/CAM composites presented moderate FS, high T and antagonist friendly behavior. Glass-ceramic demonstrated the most favorable DR and lowest TBW on the material side. Copyright © 2015 Elsevier Ltd. All rights reserved.

USE OF CONTINUOUS MEASUREMENTS OF INTEGRAL AEROSOL PARAMETERS TO ESTIMATE PARTICLE SURFACE AREA

EPA Science Inventory

This study was undertaken because of interest in using particle surface area as an indicator for studies of the health effects of particulate matter. First, we wished to determine the integral parameter of the size distribution measured by the electrical aerosol detector. Secon...

Wear, strength, modulus and hardness of CAD/CAM restorative materials.

PubMed

Lawson, Nathaniel C; Bansal, Ritika; Burgess, John O

2016-11-01

To measure the mechanical properties of several CAD/CAM materials, including lithium disilicate (e.max CAD), lithium silicate/zirconia (Celtra Duo), 3 resin composites (Cerasmart, Lava Ultimate, Paradigm MZ100), and a polymer infiltrated ceramic (Enamic). CAD/CAM blocks were sectioned into 2.5mm×2.5mm×16mm bars for flexural strength and elastic modulus testing and 4mm thick blocks for hardness and wear testing. E.max CAD and half the Celtra Duo specimens were treated in a furnace. Flexural strength specimens (n=10) were tested in a three-point bending fixture. Vickers microhardness (n=2, 5 readings per specimen) was measured with a 1kg load and 15s dwell time. The CAD/CAM materials as well as labial surfaces of human incisors were mounted in the UAB wear device. Cusps of human premolars were mounted as antagonists. Specimens were tested for 400,000 cycles at 20N force, 2mm sliding distance, 1Hz frequency, 24°C, and 33% glycerin lubrication. Volumetric wear and opposing enamel wear were measured with non-contact profilometry. Data were analyzed with 1-way ANOVA and Tukey post-hoc analysis (alpha=0.05). Specimens were observed with SEM. Properties were different for each material (p<0.01). E.max CAD and Celtra Duo were generally stronger, stiffer, and harder than the other materials. E.max CAD, Celtra Duo, Enamic, and enamel demonstrated signs of abrasive wear, whereas Cerasmart, Lava Ultimate, Paradigm MZ100 demonstrated signs of fatigue. Resin composite and resin infiltrated ceramic materials have demonstrated adequate wear resistance for load bearing restorations, however, they will require at least similar material thickness as lithium disilicate restorations due to their strength. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

CAD mutations and uridine-responsive epileptic encephalopathy.

PubMed

Koch, Johannes; Mayr, Johannes A; Alhaddad, Bader; Rauscher, Christian; Bierau, Jörgen; Kovacs-Nagy, Reka; Coene, Karlien L M; Bader, Ingrid; Holzhacker, Monika; Prokisch, Holger; Venselaar, Hanka; Wevers, Ron A; Distelmaier, Felix; Polster, Tilman; Leiz, Steffen; Betzler, Cornelia; Strom, Tim M; Sperl, Wolfgang; Meitinger, Thomas; Wortmann, Saskia B; Haack, Tobias B

2017-02-01

Unexplained global developmental delay and epilepsy in childhood pose a major socioeconomic burden. Progress in defining the molecular bases does not often translate into effective treatment. Notable exceptions include certain inborn errors of metabolism amenable to dietary intervention. CAD encodes a multifunctional enzyme involved in de novo pyrimidine biosynthesis. Alternatively, pyrimidines can be recycled from uridine. Exome sequencing in three families identified biallelic CAD mutations in four children with global developmental delay, epileptic encephalopathy, and anaemia with anisopoikilocytosis. Two died aged 4 and 5 years after a neurodegenerative disease course. Supplementation of the two surviving children with oral uridine led to immediate cessation of seizures in both. A 4-year-old female, previously in a minimally conscious state, began to communicate and walk with assistance after 9 weeks of treatment. A 3-year-old female likewise showed developmental progress. Blood smears normalized and anaemia resolved. We establish CAD as a gene confidently implicated in this neurometabolic disorder, characterized by co-occurrence of global developmental delay, dyserythropoietic anaemia and seizures. While the natural disease course can be lethal in early childhood, our findings support the efficacy of uridine supplementation, rendering CAD deficiency a treatable neurometabolic disorder and therefore a potential condition for future (genetic) newborn screening. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Ceramic dental biomaterials and CAD/CAM technology: state of the art.

PubMed

Li, Raymond Wai Kim; Chow, Tak Wah; Matinlinna, Jukka Pekka

2014-10-01

Ceramics are widely used as indirect restorative materials in dentistry because of their high biocompatibility and pleasing aesthetics. The objective is to review the state of the arts of CAD/CAM all-ceramic biomaterials. CAD/CAM all-ceramic biomaterials are highlighted and a subsequent literature search was conducted for the relevant subjects using PubMed followed by manual search. Developments in CAD/CAM technology have catalyzed researches in all-ceramic biomaterials and their applications. Feldspathic glass ceramic and glass infiltrated ceramic can be fabricated by traditional laboratory methods or CAD/CAM. The advent of polycrystalline ceramics is a direct result of CAD/CAM technology without which the fabrication would not have been possible. The clinical uses of these ceramics have met with variable clinical success. Multiple options are now available to the clinicians for the fabrication of aesthetic all ceramic restorations. Copyright © 2014 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

Aerosol typing - key information from aerosol studies

NASA Astrophysics Data System (ADS)

Mona, Lucia; Kahn, Ralph; Papagiannopoulos, Nikolaos; Holzer-Popp, Thomas; Pappalardo, Gelsomina

2016-04-01

Aerosol typing is a key source of aerosol information from ground-based and satellite-borne instruments. Depending on the specific measurement technique, aerosol typing can be used as input for retrievals or represents an output for other applications. Typically aerosol retrievals require some a priori or external aerosol type information. The accuracy of the derived aerosol products strongly depends on the reliability of these assumptions. Different sensors can make use of different aerosol type inputs. A critical review and harmonization of these procedures could significantly reduce related uncertainties. On the other hand, satellite measurements in recent years are providing valuable information about the global distribution of aerosol types, showing for example the main source regions and typical transport paths. Climatological studies of aerosol load at global and regional scales often rely on inferred aerosol type. There is still a high degree of inhomogeneity among satellite aerosol typing schemes, which makes the use different sensor datasets in a consistent way difficult. Knowledge of the 4d aerosol type distribution at these scales is essential for understanding the impact of different aerosol sources on climate, precipitation and air quality. All this information is needed for planning upcoming aerosol emissions policies. The exchange of expertise and the communication among satellite and ground-based measurement communities is fundamental for improving long-term dataset consistency, and for reducing aerosol type distribution uncertainties. Aerosol typing has been recognized as one of its high-priority activities of the AEROSAT (International Satellite Aerosol Science Network, http://aero-sat.org/) initiative. In the AEROSAT framework, a first critical review of aerosol typing procedures has been carried out. The review underlines the high heterogeneity in many aspects: approach, nomenclature, assumed number of components and parameters used for the

A new data integration approach for AutoCAD and GIS

NASA Astrophysics Data System (ADS)

Ye, Hongmei; Li, Yuhong; Wang, Cheng; Li, Lijun

2006-10-01

GIS has its advantages both on spatial data analysis and management, particularly on the geometric and attributive information management, which has also attracted lots attentions among researchers around world. AutoCAD plays more and more important roles as one of the main data sources of GIS. Various work and achievements can be found in the related literature. However, the conventional data integration from AutoCAD to GIS is time-consuming, which also can cause the information loss both in the geometric aspects and the attributive aspects for a large system. It is necessary and urgent to sort out new approach and algorithm for the efficient high-quality data integration. In this paper, a novel data integration approach from AutoCAD to GIS will be introduced based on the spatial data mining technique through the data structure analysis both in the AutoCAD and GIS. A practicable algorithm for the data conversion from CAD to GIS will be given as well. By a designed evaluation scheme, the accuracy of the conversion both in the geometric and the attributive information will be demonstrated. Finally, the validity and feasibility of the new approach will be shown by an experimental analysis.

Comparison of Flexural Strength of Different CAD/CAM PMMA-Based Polymers.

PubMed

Alp, Gülce; Murat, Sema; Yilmaz, Burak

2018-01-28

To compare the flexural strength of different computer-aided design/computer-aided manufacturing (CAD/CAM) poly(methyl methacrylate)-based (PMMA) polymers and conventional interim resin materials after thermocycling. Rectangular-shaped specimens (n = 15, for each material) (25 × 2 × 2 mm 3 ) were fabricated from 3 CAD/CAM PMMA-based polymers (Telio CAD [T]; M-PM-Disc [M]; Polident-PMMA [P]), 1 bis-acrylate composite resin (Protemp 4 [PT]), and 1 conventional PMMA (ArtConcept Artegral Dentine [C]) according to ISO 10477:2004 Standards (Dentistry-Polymer-Based Crown and Bridge Materials). The specimens were subjected to 10,000 thermocycles (5 to 55°C). Three-point flexural strength of the specimens was tested in a universal testing machine at a 1.0 mm/min crosshead speed, and the flexural strength data (σ) were calculated (MPa). The flexural strength values were statistically analyzed using 1-way ANOVA, and Tukey HSD post-hoc test for multiple comparisons (α = 0.05). Flexural strength values ranged between 66.1 ± 13.1 and 131.9 ± 19.8 MPa. There were significant differences among the flexural strengths of tested materials, except for between T and P CAD/CAM PMMA-based polymers (p > 0.05). CAD/CAM PMMA-based polymer M had the highest flexural strength and conventional PMMA had the lowest (p < 0.05). CAD/CAM PMMA-based T and P polymers had significantly higher flexural strength than the bis-acrylate composite resin (p < 0.05), and conventional PMMA (p < 0.0001), and significantly lower flexural strength compared to CAD/CAM PMMA-based M (p < 0.05). The flexural strength of CAD/CAM PMMA-based polymers was greater than the flexural strength of bis-acrylate composite resin, which had a greater flexural strength compared to conventional PMMA resin. © 2018 by the American College of Prosthodontists.

Note: Real time optical sensing of alpha-radiation emitting radioactive aerosols based on solid state nuclear track detector.

PubMed

Kulkarni, A; Ha, S; Joshirao, P; Manchanda, V; Bak, M S; Kim, T

2015-06-01

A sensitive radioactive aerosols sensor has been designed and developed. Its design guidance is based on the need for a low operational cost and reliable measurements to provide daily aerosol monitoring. The exposure of diethylene-glycol bis (allylcarbonate) to radiation causes modification of its physico-chemical properties like surface roughness and reflectance. In the present study, optical sensor based on the reflectance measurement has been developed with an aim to monitor real time presence of alpha radioactive aerosols emitted from thorium nitrate hydrate. The results shows that the fabricated sensor can detect 0.0157 kBq to 0.1572 kBq of radio activity by radioactive aerosols generated from (Th(NO3)4 ⋅ 5H2O) at 0.1 ml/min flow rate. The proposed instrument will be helpful to monitor radioactive aerosols in/around a nuclear facility, building construction sites, mines, and granite polishing factories.

Comparative fracture strength analysis of Lava and Digident CAD/CAM zirconia ceramic crowns

PubMed Central

Kwon, Taek-Ka; Pak, Hyun-Soon; Han, Jung-Suk; Lee, Jai-Bong; Kim, Sung-Hun

2013-01-01

PURPOSE All-ceramic crowns are subject to fracture during function. To minimize this common clinical complication, zirconium oxide has been used as the framework for all-ceramic crowns. The aim of this study was to compare the fracture strengths of two computer-aided design/computer-aided manufacturing (CAD/CAM) zirconia crown systems: Lava and Digident. MATERIALS AND METHODS Twenty Lava CAD/CAM zirconia crowns and twenty Digident CAD/CAM zirconia crowns were fabricated. A metal die was also duplicated from the original prepared tooth for fracture testing. A universal testing machine was used to determine the fracture strength of the crowns. RESULTS The mean fracture strengths were as follows: 54.9 ± 15.6 N for the Lava CAD/CAM zirconia crowns and 87.0 ± 16.0 N for the Digident CAD/CAM zirconia crowns. The difference between the mean fracture strengths of the Lava and Digident crowns was statistically significant (P<.001). Lava CAD/CAM zirconia crowns showed a complete fracture of both the veneering porcelain and the core whereas the Digident CAD/CAM zirconia crowns showed fracture only of the veneering porcelain. CONCLUSION The fracture strengths of CAD/CAM zirconia crowns differ depending on the compatibility of the core material and the veneering porcelain. PMID:23755332

Comparative fracture strength analysis of Lava and Digident CAD/CAM zirconia ceramic crowns.

PubMed

Kwon, Taek-Ka; Pak, Hyun-Soon; Yang, Jae-Ho; Han, Jung-Suk; Lee, Jai-Bong; Kim, Sung-Hun; Yeo, In-Sung

2013-05-01

All-ceramic crowns are subject to fracture during function. To minimize this common clinical complication, zirconium oxide has been used as the framework for all-ceramic crowns. The aim of this study was to compare the fracture strengths of two computer-aided design/computer-aided manufacturing (CAD/CAM) zirconia crown systems: Lava and Digident. Twenty Lava CAD/CAM zirconia crowns and twenty Digident CAD/CAM zirconia crowns were fabricated. A metal die was also duplicated from the original prepared tooth for fracture testing. A universal testing machine was used to determine the fracture strength of the crowns. THE MEAN FRACTURE STRENGTHS WERE AS FOLLOWS: 54.9 ± 15.6 N for the Lava CAD/CAM zirconia crowns and 87.0 ± 16.0 N for the Digident CAD/CAM zirconia crowns. The difference between the mean fracture strengths of the Lava and Digident crowns was statistically significant (P<.001). Lava CAD/CAM zirconia crowns showed a complete fracture of both the veneering porcelain and the core whereas the Digident CAD/CAM zirconia crowns showed fracture only of the veneering porcelain. The fracture strengths of CAD/CAM zirconia crowns differ depending on the compatibility of the core material and the veneering porcelain.

Stress-induced alteration of left ventricular eccentricity: An additional marker of multivessel CAD.

PubMed

Gimelli, Alessia; Liga, Riccardo; Giorgetti, Assuero; Casagranda, Mirta; Marzullo, Paolo

2017-03-28

Abnormal left ventricular (LV) eccentricity index (EI) is a marker of adverse cardiac remodeling. However, the interaction between stress-induced alterations of EI and major cardiac parameters has not been explored. We sought to evaluate the relationship between LV EI and coronary artery disease (CAD) burden in patients submitted to myocardial perfusion imaging (MPI). Three-hundred and forty-three patients underwent MPI and coronary angiography. LV ejection fraction (EF) and EI were computed from gated stress images as measures of stress-induced functional impairment. One-hundred and thirty-six (40%), 122 (35%), and 85 (25%) patients had normal coronary arteries, single-vessel CAD, and multivessel CAD, respectively. Post-stress EI was lower in patients with multivessel CAD than in those with normal coronary arteries and single-vessel CAD (P = 0.001). This relationship was confirmed only in patients undergoing exercise stress test, where a lower post-stress EI predicted the presence of multivessel CAD (P = 0.039). Post-stress alterations of LV EI on MPI may unmask the presence of multivessel CAD.

Outdoor chamber measurements of biological aerosols with a passive FTIR spectrometer

NASA Astrophysics Data System (ADS)

D'Amico, Francis M.; Emge, Darren K.; Roelant, Geoffrey J.

2004-02-01

Outdoor measurements of dry bacillus subtilis (BG) spores were conducted with a passive Fourier transform infrared (FTIR) spectrometer using two types of chambers. One was a large open-ended cell, and the other was a canyon of similar dimensions. The canyon exposes the aerosol plume to downwelling sky radiance, while the open-ended cell does not. The goal of the experiments was to develop a suitable test methodology for evaluation of passive standoff detectors for open-air aerosol measurements. Dry BG aerosol particles were dispersed with a blower through an opening in the side of the chamber to create a pseudo-stationary plume, wind conditions permitting. Numerous trials were performed with the FTIR spectrometer positioned to view mountain, sky and mixed mountain-sky backgrounds. This paper will discuss the results of the FTIR measurements for BG and Kaolin dust releases.

CAD-Based Shielding Analysis for ITER Port Diagnostics

NASA Astrophysics Data System (ADS)

Serikov, Arkady; Fischer, Ulrich; Anthoine, David; Bertalot, Luciano; De Bock, Maartin; O'Connor, Richard; Juarez, Rafael; Krasilnikov, Vitaly

2017-09-01

Radiation shielding analysis conducted in support of design development of the contemporary diagnostic systems integrated inside the ITER ports is relied on the use of CAD models. This paper presents the CAD-based MCNP Monte Carlo radiation transport and activation analyses for the Diagnostic Upper and Equatorial Port Plugs (UPP #3 and EPP #8, #17). The creation process of the complicated 3D MCNP models of the diagnostics systems was substantially accelerated by application of the CAD-to-MCNP converter programs MCAM and McCad. High performance computing resources of the Helios supercomputer allowed to speed-up the MCNP parallel transport calculations with the MPI/OpenMP interface. The found shielding solutions could be universal, reducing ports R&D costs. The shield block behind the Tritium and Deposit Monitor (TDM) optical box was added to study its influence on Shut-Down Dose Rate (SDDR) in Port Interspace (PI) of EPP#17. Influence of neutron streaming along the Lost Alpha Monitor (LAM) on the neutron energy spectra calculated in the Tangential Neutron Spectrometer (TNS) of EPP#8. For the UPP#3 with Charge eXchange Recombination Spectroscopy (CXRS-core), an excessive neutron streaming along the CXRS shutter, which should be prevented in further design iteration.

Database construction for PromoterCAD: synthetic promoter design for mammals and plants.

PubMed

Nishikata, Koro; Cox, Robert Sidney; Shimoyama, Sayoko; Yoshida, Yuko; Matsui, Minami; Makita, Yuko; Toyoda, Tetsuro

2014-03-21

Synthetic promoters can control a gene's timing, location, and expression level. The PromoterCAD web server ( http://promotercad.org ) allows the design of synthetic promoters to control plant gene expression, by novel arrangement of cis-regulatory elements. Recently, we have expanded PromoterCAD's scope with additional plant and animal data: (1) PLACE (Plant Cis-acting Regulatory DNA Elements), including various sized sequence motifs; (2) PEDB (Mammalian Promoter/Enhancer Database), including gene expression data for mammalian tissues. The plant PromoterCAD data now contains 22 000 Arabidopsis thaliana genes, 2 200 000 microarray measurements in 20 growth conditions and 79 tissue organs and developmental stages, while the new mammalian PromoterCAD data contains 679 Mus musculus genes and 65 000 microarray measurements in 96 tissue organs and cell types ( http://promotercad.org/mammal/ ). This work presents step-by-step instructions for adding both regulatory motif and gene expression data to PromoterCAD, to illustrate how users can expand PromoterCAD functionality for their own applications and organisms.

Format conversion between CAD data and GIS data based on ArcGIS

NASA Astrophysics Data System (ADS)

Xie, Qingqing; Wei, Bo; Zhang, Kailin; Wang, Zhichao

2015-12-01

To make full use of the data resources and realize a sharing for the different types of data in different industries, a method of format conversion between CAD data and GIS data based on ArcGIS was proposed. To keep the integrity of the converted data, some key steps to process CAD data before conversion were made in AutoCAD. For examples, deleting unnecessary elements such as title, border and legend avoided the appearance of unnecessary elements after conversion, as layering data again by a national standard avoided the different types of elements to appear in a same layer after conversion. In ArcGIS, converting CAD data to GIS data was executed by the correspondence of graphic element classification between AutoCAD and ArcGIS. In addition, an empty geographic database and feature set was required to create in ArcGIS for storing the text data of CAD data. The experimental results show that the proposed method avoids a large amount of editing work in data conversion and maintains the integrity of spatial data and attribute data between before and after conversion.

Understanding dental CAD/CAM for restorations--accuracy from a mechanical engineering viewpoint.

PubMed

Tapie, Laurent; Lebon, Nicolas; Mawussi, Bernardin; Fron-Chabouis, Hélène; Duret, Francois; Attal, Jean-Pierre

2015-01-01

As is the case in the field of medicine, as well as in most areas of daily life, digital technology is increasingly being introduced into dental practice. Computer-aided design/ computer-aided manufacturing (CAD/CAM) solutions are available not only for chairside practice but also for creating inlays, crowns, fixed partial dentures (FPDs), implant abutments, and other dental prostheses. CAD/CAM dental practice can be considered as the handling of devices and software processing for the almost automatic design and creation of dental restorations. However, dentists who want to use dental CAD/CAM systems often do not have enough information to understand the variations offered by such technology practice. Knowledge of the random and systematic errors in accuracy with CAD/CAM systems can help to achieve successful restorations with this technology, and help with the purchasing of a CAD/CAM system that meets the clinical needs of restoration. This article provides a mechanical engineering viewpoint of the accuracy of CAD/ CAM systems, to help dentists understand the impact of this technology on restoration accuracy.

PromoterCAD: data-driven design of plant regulatory DNA

PubMed Central

Cox, Robert Sidney; Nishikata, Koro; Shimoyama, Sayoko; Yoshida, Yuko; Matsui, Minami; Makita, Yuko; Toyoda, Tetsuro

2013-01-01

Synthetic promoters can control the timing, location and amount of gene expression for any organism. PromoterCAD is a web application for designing synthetic promoters with altered transcriptional regulation. We use a data-first approach, using published high-throughput expression and motif data from for Arabidopsis thaliana to guide DNA design. We demonstrate data mining tools for finding motifs related to circadian oscillations and tissue-specific expression patterns. PromoterCAD is built on the LinkData open platform for data publication and rapid web application development, allowing new data to be easily added, and the source code modified to add new functionality. PromoterCAD URL: http://promotercad.org. LinkData URL: http://linkdata.org. PMID:23766287

3D surface and body documentation in forensic medicine: 3-D/CAD Photogrammetry merged with 3D radiological scanning.

PubMed

Thali, Michael J; Braun, Marcel; Wirth, Joachim; Vock, Peter; Dirnhofer, Richard

2003-11-01

A main goal of forensic medicine is to document and to translate medical findings to a language and/or visualization that is readable and understandable for judicial persons and for medical laymen. Therefore, in addition to classical methods, scientific cutting-edge technologies can and should be used. Through the use of the Forensic, 3-D/CAD-supported Photogrammetric method the documentation of so-called "morphologic fingerprints" has been realized. Forensic, 3-D/CAD-supported Photogrammetry creates morphologic data models of the injury and of the suspected injury-causing instrument allowing the evaluation of a match between the injury and the instrument. In addition to the photogrammetric body surface registration, the radiological documentation provided by a volume scan (i.e., spiral, multi-detector CT, or MRI) registers the sub-surface injury, which is not visible to Photogrammetry. The new, combined method of merging Photogrammetry and Radiology data sets creates the potential to perform many kinds of reconstructions and postprocessing of (patterned) injuries in the realm of forensic medical case work. Using this merging method of colored photogrammetric surface and gray-scale radiological internal documentation, a great step towards a new kind of reality-based, high-tech wound documentation and visualization in forensic medicine is made. The combination of the methods of 3D/CAD Photogrammetry and Radiology has the advantage of being observer-independent, non-subjective, non-invasive, digitally storable over years or decades and even transferable over the web for second opinion.

CAD-based Automatic Modeling Method for Geant4 geometry model Through MCAM

NASA Astrophysics Data System (ADS)

Wang, Dong; Nie, Fanzhi; Wang, Guozhong; Long, Pengcheng; LV, Zhongliang; LV, Zhongliang

2014-06-01

Geant4 is a widely used Monte Carlo transport simulation package. Before calculating using Geant4, the calculation model need be established which could be described by using Geometry Description Markup Language (GDML) or C++ language. However, it is time-consuming and error-prone to manually describe the models by GDML. Automatic modeling methods have been developed recently, but there are some problem existed in most of present modeling programs, specially some of them were not accurate or adapted to specifically CAD format. To convert the GDML format models to CAD format accurately, a Geant4 Computer Aided Design (CAD) based modeling method was developed for automatically converting complex CAD geometry model into GDML geometry model. The essence of this method was dealing with CAD model represented with boundary representation (B-REP) and GDML model represented with constructive solid geometry (CSG). At first, CAD model was decomposed to several simple solids which had only one close shell. And then the simple solid was decomposed to convex shell set. Then corresponding GDML convex basic solids were generated by the boundary surfaces getting from the topological characteristic of a convex shell. After the generation of these solids, GDML model was accomplished with series boolean operations. This method was adopted in CAD/Image-based Automatic Modeling Program for Neutronics & Radiation Transport (MCAM), and tested with several models including the examples in Geant4 install package. The results showed that this method could convert standard CAD model accurately, and can be used for Geant4 automatic modeling.

CAD in der Praxis

NASA Astrophysics Data System (ADS)

Labisch, Susanna

Konstruktion und Fertigung erfolgen in der Praxis fast ausschließlich rechnerunterstützt. Mit diesem Rechnereinsatz beim Konstruieren (CAD, Computer Aided Design) und Fertigen CAM (Computer Aided Manufacturing) scheint die technische Zeichnung an Bedeutung zu verlieren, da die Verständigung zwischen Konstruktions- und Fertigungsabteilung primär durch den Austausch digitaler Daten erfolgen kann.

X-ray Vision for Aerosol Scientists: LCLS Snapshots of Soot (Narrated)

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

None

2012-10-22

This short conceptual animation depicts how scientists can now simultaneously capture fractal morphology (structure), chemical composition and nanoscale imagery of individual aerosol particles in flight. These particles, known as "PM2.5" because they are smaller than 2.5 microns in diameter, affect climate by interacting with sunlight and impact human health by entering the lungs. The single LCLS laser pulses travel to the Atomic, Molecular and Optical Sciences (AMO) laboratory in the Near Experimental Hall. As we zoom in, we see deep inside a simplified aerosol inlet, where the complex fractal structure of the soot particles, each one completely unique, is shown.more » Individual soot particles are then delivered into the pulses of the LCLS beam, which destroys them. X-rays are scattered to the detector before the particle is destroyed, giving information about the morphology of the particle. Ion fragments released in the explosion are sent into a mass spectrometer, which measures their mass-to-charge ratio -- giving scientists information about the chemical composition of the particle. Many different particles are analyzed in this manner, allowing scientists to probe variations in the particles due to changes in their environment before being sent through the aerosol inlet. The final visual of aerosols emitted from a factory is representative of the goal that such LCLS aerosol dynamics experiments can provide critical feedback into modeling and understanding combustion, aerosol processes in manufacturing or aerosol effects on climate change.« less

X-ray Vision for Aerosol Scientists: LCLS Snapshots of Soot (Narrated)

ScienceCinema

None

2018-01-26

This short conceptual animation depicts how scientists can now simultaneously capture fractal morphology (structure), chemical composition and nanoscale imagery of individual aerosol particles in flight. These particles, known as "PM2.5" because they are smaller than 2.5 microns in diameter, affect climate by interacting with sunlight and impact human health by entering the lungs. The single LCLS laser pulses travel to the Atomic, Molecular and Optical Sciences (AMO) laboratory in the Near Experimental Hall. As we zoom in, we see deep inside a simplified aerosol inlet, where the complex fractal structure of the soot particles, each one completely unique, is shown. Individual soot particles are then delivered into the pulses of the LCLS beam, which destroys them. X-rays are scattered to the detector before the particle is destroyed, giving information about the morphology of the particle. Ion fragments released in the explosion are sent into a mass spectrometer, which measures their mass-to-charge ratio -- giving scientists information about the chemical composition of the particle. Many different particles are analyzed in this manner, allowing scientists to probe variations in the particles due to changes in their environment before being sent through the aerosol inlet. The final visual of aerosols emitted from a factory is representative of the goal that such LCLS aerosol dynamics experiments can provide critical feedback into modeling and understanding combustion, aerosol processes in manufacturing or aerosol effects on climate change.

Multi-aperture laser transmissometer system for long-path aerosol extinction rate measurement.

PubMed

Wu, Chensheng; Rzasa, John R; Ko, Jonathan; Paulson, Daniel A; Coffaro, Joseph; Spychalsky, Jonathan; Crabbs, Robert F; Davis, Christopher C

2018-01-20

We present the theory, design, simulation, and experimental evaluations of a new laser transmissometer system for aerosol extinction rate measurement over long paths. The transmitter emits an ON/OFF modulated Gaussian beam that does not require strict collimation. The receiver uses multiple point detectors to sample the sub-aperture irradiance of the arriving beam. The sparse detector arrangement makes our transmissometer system immune to turbulence-induced beam distortion and beam wander caused by the atmospheric channel. Turbulence effects often cause spatial discrepancies in beam propagation and lead to miscalculation of true power loss when using the conventional approach of measuring the total beam power directly with a large-aperture optical concentrator. Our transmissometer system, on the other hand, combines the readouts from distributed detectors to rule out turbulence-induced temporal power fluctuations. As a result, we show through both simulation and field experiments that our transmissometer system works accurately with turbulence strength Cn2 up to 10 -12   m -2/3 over a typical 1-km atmospheric channel. In application, our turbulence- and weather-resistant laser transmissometer system has significant advantages for the measurement and study of aerosol concentration, absorption, and scattering properties, which are crucial for directed energy systems, ground-level free-space optical communication systems, environmental monitoring, and weather forecasting.

Comparison of denture tooth movement between CAD-CAM and conventional fabrication techniques.

PubMed

Goodacre, Brian J; Goodacre, Charles J; Baba, Nadim Z; Kattadiyil, Mathew T

2018-01-01

Data comparing the denture tooth movement of computer-aided design and computer-aided manufacturing (CAD-CAM) and conventional denture processing techniques are lacking. The purpose of this in vitro study was to compare the denture tooth movement of pack-and-press, fluid resin, injection, CAD-CAM-bonded, and CAD-CAM monolithic techniques for fabricating dentures to determine which process produces the most accurate and reproducible prosthesis. A total of 50 dentures were evaluated, 10 for each of the 5 groups. A master denture was fabricated and milled from prepolymerized poly(methyl methacrylate). For the conventional processing techniques (pack-and-press, fluid resin, and injection) a polyvinyl siloxane putty mold of the master denture was made in which denture teeth were placed and molten wax injected. The cameo surface of each wax-festooned denture was laser scanned, resulting in a standard tessellation language (STL) format file. The CAD-CAM dentures included 2 subgroups: CAD-CAM-bonded teeth in which the denture teeth were bonded into the milled denture base and CAD-CAM monolithic teeth in which the denture teeth were milled as part of the denture base. After all specimens had been fabricated, they were hydrated for 24 hours, and the cameo surface laser scanned. The preprocessing and postprocessing scan files of each denture were superimposed using surface-matching software. Measurements were made at 64 locations, allowing evaluation of denture tooth movement in a buccal, lingual, mesial-distal, and occlusal direction. The use of median and interquartile range values was used to assess accuracy and reproducibility. Levene and Kruskal-Wallis analyses of variance were used to evaluate differences between processing techniques (α=.05). The CAD-CAM monolithic technique was the most accurate, followed by fluid resin, CAD-CAM-bonded, pack-and-press, and injection. CAD-CAM monolithic technique was the most reproducible, followed by pack-and-press, CAD

In Vitro Analysis of the Fracture Resistance of CAD/CAM Denture Base Resins.

PubMed

Steinmassl, Otto; Offermanns, Vincent; Stöckl, Wolfgang; Dumfahrt, Herbert; Grunert, Ingrid; Steinmassl, Patricia-Anca

2018-03-08

Computer-aided design and computer-aided manufacturing (CAD/CAM) denture base manufacturers claim to produce their resin pucks under high heat and pressure. Therefore, CAD/CAM dentures are assumed to have enhanced mechanical properties and, as a result, are often produced with lower denture base thicknesses than conventional, manually fabricated dentures. The aim of this study was to investigate if commercially available CAD/CAM denture base resins have more favourable mechanical properties than conventionally processed denture base resins. For this purpose, a series of three-point bending tests conforming to ISO specifications were performed on a total of 80 standardised, rectangular CAD/CAM denture base resin specimens from five different manufacturers (AvaDent, Baltic Denture System, Vita VIONIC, Whole You Nexteeth, and Wieland Digital Dentures). A heat-polymerising resin and an autopolymerising resin served as the control groups. The breaking load, fracture toughness, and the elastic modulus were assessed. Additionally, the fracture surface roughness and texture were investigated. Only one CAD/CAM resin showed a significantly increased breaking load. Two CAD/CAM resins had a significantly higher fracture toughness than the control groups, and all CAD/CAM resins had higher elastic moduli than the controls. Our results indicate that CAD/CAM denture base resins do not generally have better mechanical properties than manually processed resins. Therefore, the lower minimum denture base thicknesses should be regarded with some caution.

In Vitro Analysis of the Fracture Resistance of CAD/CAM Denture Base Resins

PubMed Central

Stöckl, Wolfgang; Dumfahrt, Herbert; Grunert, Ingrid

2018-01-01

Computer-aided design and computer-aided manufacturing (CAD/CAM) denture base manufacturers claim to produce their resin pucks under high heat and pressure. Therefore, CAD/CAM dentures are assumed to have enhanced mechanical properties and, as a result, are often produced with lower denture base thicknesses than conventional, manually fabricated dentures. The aim of this study was to investigate if commercially available CAD/CAM denture base resins have more favourable mechanical properties than conventionally processed denture base resins. For this purpose, a series of three-point bending tests conforming to ISO specifications were performed on a total of 80 standardised, rectangular CAD/CAM denture base resin specimens from five different manufacturers (AvaDent, Baltic Denture System, Vita VIONIC, Whole You Nexteeth, and Wieland Digital Dentures). A heat-polymerising resin and an autopolymerising resin served as the control groups. The breaking load, fracture toughness, and the elastic modulus were assessed. Additionally, the fracture surface roughness and texture were investigated. Only one CAD/CAM resin showed a significantly increased breaking load. Two CAD/CAM resins had a significantly higher fracture toughness than the control groups, and all CAD/CAM resins had higher elastic moduli than the controls. Our results indicate that CAD/CAM denture base resins do not generally have better mechanical properties than manually processed resins. Therefore, the lower minimum denture base thicknesses should be regarded with some caution. PMID:29518022

Anniversary Paper: History and status of CAD and quantitative image analysis: The role of Medical Physics and AAPM

PubMed Central

Giger, Maryellen L.; Chan, Heang-Ping; Boone, John

2008-01-01

The roles of physicists in medical imaging have expanded over the years, from the study of imaging systems (sources and detectors) and dose to the assessment of image quality and perception, the development of image processing techniques, and the development of image analysis methods to assist in detection and diagnosis. The latter is a natural extension of medical physicists’ goals in developing imaging techniques to help physicians acquire diagnostic information and improve clinical decisions. Studies indicate that radiologists do not detect all abnormalities on images that are visible on retrospective review, and they do not always correctly characterize abnormalities that are found. Since the 1950s, the potential use of computers had been considered for analysis of radiographic abnormalities. In the mid-1980s, however, medical physicists and radiologists began major research efforts for computer-aided detection or computer-aided diagnosis (CAD), that is, using the computer output as an aid to radiologists—as opposed to a completely automatic computer interpretation—focusing initially on methods for the detection of lesions on chest radiographs and mammograms. Since then, extensive investigations of computerized image analysis for detection or diagnosis of abnormalities in a variety of 2D and 3D medical images have been conducted. The growth of CAD over the past 20 years has been tremendous—from the early days of time-consuming film digitization and CPU-intensive computations on a limited number of cases to its current status in which developed CAD approaches are evaluated rigorously on large clinically relevant databases. CAD research by medical physicists includes many aspects—collecting relevant normal and pathological cases; developing computer algorithms appropriate for the medical interpretation task including those for segmentation, feature extraction, and classifier design; developing methodology for assessing CAD performance; validating the

Anniversary Paper: History and status of CAD and quantitative image analysis: The role of Medical Physics and AAPM

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

Giger, Maryellen L.; Chan, Heang-Ping; Boone, John

2008-12-15

The roles of physicists in medical imaging have expanded over the years, from the study of imaging systems (sources and detectors) and dose to the assessment of image quality and perception, the development of image processing techniques, and the development of image analysis methods to assist in detection and diagnosis. The latter is a natural extension of medical physicists' goals in developing imaging techniques to help physicians acquire diagnostic information and improve clinical decisions. Studies indicate that radiologists do not detect all abnormalities on images that are visible on retrospective review, and they do not always correctly characterize abnormalities thatmore » are found. Since the 1950s, the potential use of computers had been considered for analysis of radiographic abnormalities. In the mid-1980s, however, medical physicists and radiologists began major research efforts for computer-aided detection or computer-aided diagnosis (CAD), that is, using the computer output as an aid to radiologists--as opposed to a completely automatic computer interpretation--focusing initially on methods for the detection of lesions on chest radiographs and mammograms. Since then, extensive investigations of computerized image analysis for detection or diagnosis of abnormalities in a variety of 2D and 3D medical images have been conducted. The growth of CAD over the past 20 years has been tremendous--from the early days of time-consuming film digitization and CPU-intensive computations on a limited number of cases to its current status in which developed CAD approaches are evaluated rigorously on large clinically relevant databases. CAD research by medical physicists includes many aspects--collecting relevant normal and pathological cases; developing computer algorithms appropriate for the medical interpretation task including those for segmentation, feature extraction, and classifier design; developing methodology for assessing CAD performance; validating the

A SINDA thermal model using CAD/CAE technologies

NASA Technical Reports Server (NTRS)

Rodriguez, Jose A.; Spencer, Steve

1992-01-01

The approach to thermal analysis described by this paper is a technique that incorporates Computer Aided Design (CAD) and Computer Aided Engineering (CAE) to develop a thermal model that has the advantages of Finite Element Methods (FEM) without abandoning the unique advantages of Finite Difference Methods (FDM) in the analysis of thermal systems. The incorporation of existing CAD geometry, the powerful use of a pre and post processor and the ability to do interdisciplinary analysis, will be described.

Microhardness evaluations of CAD/CAM ceramics irradiated with CO2 or Nd:YAP laser

PubMed Central

Rocca, Jean Paul; Fornaini, Carlo; Medioni, Etienne; Brulat-Bouchard, Nathalie

2017-01-01

Background and aims The aim of this study was to measure the microhardness values of irradiated computer-aided design/computer-aided manufacturing (CAD/CAM) ceramics surfaces before and after thermal treatment. Materials and Methods Sixty CAD/CAM ceramic discs were prepared and grouped by material, i.e. lithium disilicate ceramic (Emax CAD) and zirconia ceramic (Emax ZirCAD). Laser irradiation at the material surface was performed with a carbon dioxide laser at 5 Watt (W) or 10 W power in continuous mode (CW mode), or with a neodymium:yttrium aluminum perovskite (Nd:YAP) laser at 10 W on graphite and non-graphite surfaces. Vickers hardness was tested at 0.3 kgf for lithium disilicate and 1 kgf for zirconia. Results Emax CAD irradiated with CO2 at 5 W increased microhardness by 6.32 GPa whereas Emax ZirCAD irradiated with Nd:YAP decreased microhardness by 17.46 GPa. Conclusion CO2 laser effectively increases the microhardness of lithium disilicate ceramics (Emax CAD). PMID:28740324

Information fusion for diabetic retinopathy CAD in digital color fundus photographs.

PubMed

Niemeijer, Meindert; Abramoff, Michael D; van Ginneken, Bram

2009-05-01

The purpose of computer-aided detection or diagnosis (CAD) technology has so far been to serve as a second reader. If, however, all relevant lesions in an image can be detected by CAD algorithms, use of CAD for automatic reading or prescreening may become feasible. This work addresses the question how to fuse information from multiple CAD algorithms, operating on multiple images that comprise an exam, to determine a likelihood that the exam is normal and would not require further inspection by human operators. We focus on retinal image screening for diabetic retinopathy, a common complication of diabetes. Current CAD systems are not designed to automatically evaluate complete exams consisting of multiple images for which several detection algorithm output sets are available. Information fusion will potentially play a crucial role in enabling the application of CAD technology to the automatic screening problem. Several different fusion methods are proposed and their effect on the performance of a complete comprehensive automatic diabetic retinopathy screening system is evaluated. Experiments show that the choice of fusion method can have a large impact on system performance. The complete system was evaluated on a set of 15,000 exams (60,000 images). The best performing fusion method obtained an area under the receiver operator characteristic curve of 0.881. This indicates that automated prescreening could be applied in diabetic retinopathy screening programs.

Aqueous aerosol SOA formation: impact on aerosol physical properties.

PubMed

Woo, Joseph L; Kim, Derek D; Schwier, Allison N; Li, Ruizhi; McNeill, V Faye

2013-01-01

Organic chemistry in aerosol water has recently been recognized as a potentially important source of secondary organic aerosol (SOA) material. This SOA material may be surface-active, therefore potentially affecting aerosol heterogeneous activity, ice nucleation, and CCN activity. Aqueous aerosol chemistry has also been shown to be a potential source of light-absorbing products ("brown carbon"). We present results on the formation of secondary organic aerosol material in aerosol water and the associated changes in aerosol physical properties from GAMMA (Gas-Aerosol Model for Mechanism Analysis), a photochemical box model with coupled gas and detailed aqueous aerosol chemistry. The detailed aerosol composition output from GAMMA was coupled with two recently developed modules for predicting a) aerosol surface tension and b) the UV-Vis absorption spectrum of the aerosol, based on our previous laboratory observations. The simulation results suggest that the formation of oligomers and organic acids in bulk aerosol water is unlikely to perturb aerosol surface tension significantly. Isoprene-derived organosulfates are formed in high concentrations in acidic aerosols under low-NO(x) conditions, but more experimental data are needed before the potential impact of these species on aerosol surface tension may be evaluated. Adsorption of surfactants from the gas phase may further suppress aerosol surface tension. Light absorption by aqueous aerosol SOA material is driven by dark glyoxal chemistry and is highest under high-NO(x) conditions, at high relative humidity, in the early morning hours. The wavelength dependence of the predicted absorption spectra is comparable to field observations and the predicted mass absorption efficiencies suggest that aqueous aerosol chemistry can be a significant source of aerosol brown carbon under urban conditions.

A visual LISP program for voxelizing AutoCAD solid models

NASA Astrophysics Data System (ADS)

Marschallinger, Robert; Jandrisevits, Carmen; Zobl, Fritz

2015-01-01

AutoCAD solid models are increasingly recognized in geological and geotechnical 3D modeling. In order to bridge the currently existing gap between AutoCAD solid models and the grid modeling realm, a Visual LISP program is presented that converts AutoCAD solid models into voxel arrays. Acad2Vox voxelizer works on a 3D-model that is made up of arbitrary non-overlapping 3D-solids. After definition of the target voxel array geometry, 3D-solids are scanned at grid positions and properties are streamed to an ASCII output file. Acad2Vox has a novel voxelization strategy that combines a hierarchical reduction of sampling dimensionality with an innovative use of AutoCAD-specific methods for a fast and memory-saving operation. Acad2Vox provides georeferenced, voxelized analogs of 3D design data that can act as regions-of-interest in later geostatistical modeling and simulation. The Supplement includes sample geological solid models with instructions for practical work with Acad2Vox.

Management of CAD/CAM information: Key to improved manufacturing productivity

NASA Technical Reports Server (NTRS)

Fulton, R. E.; Brainin, J.

1984-01-01

A key element to improved industry productivity is effective management of CAD/CAM information. To stimulate advancements in this area, a joint NASA/Navy/Industry project designated Integrated Programs for Aerospace-Vehicle Design (IPAD) is underway with the goal of raising aerospace industry productivity through advancement of technology to integrate and manage information involved in the design and manufacturing process. The project complements traditional NASA/DOD research to develop aerospace design technology and the Air Force's Integrated Computer-Aided Manufacturing (ICAM) program to advance CAM technology. IPAD research is guided by an Industry Technical Advisory Board (ITAB) composed of over 100 repesentatives from aerospace and computer companies. The IPAD accomplishments to date in development of requirements and prototype software for various levels of company-wide CAD/CAM data management are summarized and plans for development of technology for management of distributed CAD/CAM data and information required to control future knowledge-based CAD/CAM systems are discussed.

Vagus-brain communication in atherosclerosis-related inflammation: a neuroimmunomodulation perspective of CAD.

PubMed

Gidron, Yori; Kupper, Nina; Kwaijtaal, Martijn; Winter, Jobst; Denollet, Johan

2007-12-01

The current understanding of the pathophysiology of atherosclerosis leading to coronary artery disease (CAD) emphasizes the role of inflammatory mediators. Given the bidirectional communication between the immune and central nervous systems, an important question is whether the brain can be "informed" about and modulate CAD-related inflammation. A candidate communicator and modulator is the vagus nerve. Until now, the vagus nerve has received attention in cardiology mainly due to its role in the parasympathetic cardiovascular response. However, the vagus nerve can also "inform" the brain about peripheral inflammation since its paraganglia have receptors for interleukin-1. Furthermore, its efferent branch has a local anti-inflammatory effect. These effects have not been considered in research on the vagus nerve in CAD or in vagus nerve stimulation trials in CAD. In addition, various behavioural interventions, including relaxation, may influence CAD prognosis by affecting vagal activity. Based on this converging evidence, we propose a neuroimmunomodulation approach to atherogenesis. In this model, the vagus nerve "informs" the brain about CAD-related cytokines; in turn, activation of the vagus (via vagus nerve stimulation, vagomimetic drugs or relaxation) induces an anti-inflammatory response that can slow down the chronic process of atherogenesis.

Repairability of CAD/CAM high-density PMMA- and composite-based polymers.

PubMed

Wiegand, Annette; Stucki, Lukas; Hoffmann, Robin; Attin, Thomas; Stawarczyk, Bogna

2015-11-01

The study aimed to analyse the shear bond strength of computer-aided design and computer-aided manufacturing (CAD/CAM) polymethyl methacrylate (PMMA)- and composite-based polymer materials repaired with a conventional methacrylate-based composite after different surface pretreatments. Each 48 specimens was prepared from six different CAD/CAM polymer materials (Ambarino high-class, artBloc Temp, CAD-Temp, Lava Ultimate, Telio CAD, Everest C-Temp) and a conventional dimethacrylate-based composite (Filtek Supreme XTE, control) and aged by thermal cycling (5000 cycles, 5-55 °C). The surfaces were left untreated or were pretreated by mechanical roughening, aluminium oxide air abrasion or silica coating/silanization (each subgroup n = 12). The surfaces were further conditioned with an etch&rinse adhesive (OptiBond FL) before the repair composite (Filtek Supreme XTE) was adhered to the surface. After further thermal cycling, shear bond strength was tested, and failure modes were assessed. Shear bond strength was statistically analysed by two- and one-way ANOVAs and Weibull statistics, failure mode by chi(2) test (p ≤ 0.05). Shear bond strength was highest for silica coating/silanization > aluminium oxide air abrasion = mechanical roughening > no surface pretreatment. Independently of the repair pretreatment, highest bond strength values were observed in the control group and for the composite-based Everest C-Temp and Ambarino high-class, while PMMA-based materials (artBloc Temp, CAD-Temp and Telio CAD) presented significantly lowest values. For all materials, repair without any surface pretreatment resulted in adhesive failures only, which mostly were reduced when surface pretreatment was performed. Repair of CAD/CAM high-density polymers requires surface pretreatment prior to adhesive and composite application. However, four out of six of the tested CAD/CAM materials did not achieve the repair bond strength of a conventional dimethacrylate

Marginal adaptation and CAD-CAM technology: A systematic review of restorative material and fabrication techniques.

PubMed

Papadiochou, Sofia; Pissiotis, Argirios L

2018-04-01

The comparative assessment of computer-aided design and computer-aided manufacturing (CAD-CAM) technology and other fabrication techniques pertaining to marginal adaptation should be documented. Limited evidence exists on the effect of restorative material on the performance of a CAD-CAM system relative to marginal adaptation. The purpose of this systematic review was to investigate whether the marginal adaptation of CAD-CAM single crowns, fixed dental prostheses, and implant-retained fixed dental prostheses or their infrastructures differs from that obtained by other fabrication techniques using a similar restorative material and whether it depends on the type of restorative material. An electronic search of English-language literature published between January 1, 2000, and June 30, 2016, was conducted of the Medline/PubMed database. Of the 55 included comparative studies, 28 compared CAD-CAM technology with conventional fabrication techniques, 12 contrasted CAD-CAM technology and copy milling, 4 compared CAD-CAM milling with direct metal laser sintering (DMLS), and 22 investigated the performance of a CAD-CAM system regarding marginal adaptation in restorations/infrastructures produced with different restorative materials. Most of the CAD-CAM restorations/infrastructures were within the clinically acceptable marginal discrepancy (MD) range. The performance of a CAD-CAM system relative to marginal adaptation is influenced by the restorative material. Compared with CAD-CAM, most of the heat-pressed lithium disilicate crowns displayed equal or smaller MD values. Slip-casting crowns exhibited similar or better marginal accuracy than those fabricated with CAD-CAM. Cobalt-chromium and titanium implant infrastructures produced using a CAD-CAM system elicited smaller MD values than zirconia. The majority of cobalt-chromium restorations/infrastructures produced by DMLS displayed better marginal accuracy than those fabricated with the casting technique. Compared with copy

Aerosol algorithm evaluation within aerosol-CCI

NASA Astrophysics Data System (ADS)

Kinne, Stefan; Schulz, Michael; Griesfeller, Jan

Properties of aerosol retrievals from space are difficult. Even data from dedicated satellite sensors face contaminations which limit the accuracy of aerosol retrieval products. Issues are the identification of complete cloud-free scenes, the need to assume aerosol compositional features in an underdetermined solution space and the requirement to characterize the background at high accuracy. Usually the development of aerosol is a slow process, requiring continuous feedback from evaluations. To demonstrate maturity, these evaluations need to cover different regions and seasons and many different aerosol properties, because aerosol composition is quite diverse and highly variable in space and time, as atmospheric aerosol lifetimes are only a few days. Three years ago the ESA Climate Change Initiative started to support aerosol retrieval efforts in order to develop aerosol retrieval products for the climate community from underutilized ESA satellite sensors. The initial focus was on retrievals of AOD (a measure for the atmospheric column amount) and of Angstrom (a proxy for aerosol size) from the ATSR and MERIS sensors on ENVISAT. The goal was to offer retrieval products that are comparable or better in accuracy than commonly used NASA products of MODIS or MISR. Fortunately, accurate reference data of ground based sun-/sky-photometry networks exist. Thus, retrieval assessments could and were conducted independently by different evaluation groups. Here, results of these evaluations for the year 2008 are summarized. The capability of these newly developed retrievals is analyzed and quantified in scores. These scores allowed a ranking of competing efforts and also allow skill comparisons of these new retrievals against existing and commonly used retrievals.

Performance evaluation of the NASA/KSC CAD/CAE and office automation LAN's

NASA Technical Reports Server (NTRS)

Zobrist, George W.

1994-01-01

This study's objective is the performance evaluation of the existing CAD/CAE (Computer Aided Design/Computer Aided Engineering) network at NASA/KSC. This evaluation also includes a similar study of the Office Automation network, since it is being planned to integrate this network into the CAD/CAE network. The Microsoft mail facility which is presently on the CAD/CAE network was monitored to determine its present usage. This performance evaluation of the various networks will aid the NASA/KSC network managers in planning for the integration of future workload requirements into the CAD/CAE network and determining the effectiveness of the planned FDDI (Fiber Distributed Data Interface) migration.

Dental students' preferences and performance in crown design: conventional wax-added versus CAD.

PubMed

Douglas, R Duane; Hopp, Christa D; Augustin, Marcus A

2014-12-01

The purpose of this study was to evaluate dental students' perceptions of traditional waxing vs. computer-aided crown design and to determine the effectiveness of either technique through comparative grading of the final products. On one of twoidentical tooth preparations, second-year students at one dental school fabricated a wax pattern for a full contour crown; on the second tooth preparation, the same students designed and fabricated an all-ceramic crown using computer-aided design (CAD) and computer-aided manufacturing (CAM) technology. Projects were graded for occlusion and anatomic form by three faculty members. On completion of the projects, 100 percent of the students (n=50) completed an eight-question, five-point Likert scalesurvey, designed to assess their perceptions of and learning associated with the two design techniques. The average grades for the crown design projects were 78.3 (CAD) and 79.1 (wax design). The mean numbers of occlusal contacts were 3.8 (CAD) and 2.9(wax design), which was significantly higher for CAD (p=0.02). The survey results indicated that students enjoyed designing afull contour crown using CAD as compared to using conventional wax techniques and spent less time designing the crown using CAD. From a learning perspective, students felt that they learned more about position and the size/strength of occlusal contacts using CAD. However, students recognized that CAD technology has limits in terms of representing anatomic contours and excursive occlusion compared to conventional wax techniques. The results suggest that crown design using CAD could be considered as an adjunct to conventional wax-added techniques in preclinical fixed prosthodontic curricula.

21 CFR 872.3661 - Optical Impression Systems for CAD/CAM.

Code of Federal Regulations, 2011 CFR

2011-04-01

... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3661 Optical Impression Systems for CAD... (CAD/CAM) is a device used to record the topographical characteristics of teeth, dental impressions, or stone models by analog or digital methods for use in the computer-assisted design and manufacturing of...

Multi-Parameter Aerosol Scattering Sensor

NASA Technical Reports Server (NTRS)

Greenberg, Paul S.; Fischer, David G.

2011-01-01

This work relates to the development of sensors that measure specific aerosol properties. These properties are in the form of integrated moment distributions, i.e., total surface area, total mass, etc., or mathematical combinations of these moment distributions. Specifically, the innovation involves two fundamental features: a computational tool to design and optimize such sensors and the embodiment of these sensors in actual practice. The measurement of aerosol properties is a problem of general interest. Applications include, but are not limited to, environmental monitoring, assessment of human respiratory health, fire detection, emission characterization and control, and pollutant monitoring. The objectives for sensor development include increased accuracy and/or dynamic range, the inclusion in a single sensor of the ability to measure multiple aerosol properties, and developing an overall physical package that is rugged, compact, and low in power consumption, so as to enable deployment in harsh or confined field applications, and as distributed sensor networks. Existing instruments for this purpose include scattering photometers, direct-reading mass instruments, Beta absorption devices, differential mobility analyzers, and gravitational samplers. The family of sensors reported here is predicated on the interaction of light and matter; specifically, the scattering of light from distributions of aerosol particles. The particular arrangement of the sensor, e.g. the wavelength(s) of incident radiation, the number and location of optical detectors, etc., can be derived so as to optimize the sensor response to aerosol properties of practical interest. A key feature of the design is the potential embodiment as an extremely compact, integrated microsensor package. This is of fundamental importance, as it enables numerous previously inaccessible applications. The embodiment of these sensors is inherently low maintenance and high reliability by design. The novel and

Sandblasting may damage the surface of composite CAD-CAM blocks.

PubMed

Yoshihara, Kumiko; Nagaoka, Noriyuki; Maruo, Yukinori; Nishigawa, Goro; Irie, Masao; Yoshida, Yasuhiro; Van Meerbeek, Bart

2017-03-01

CAD-CAM blocks to fabricate semi-direct and indirect restorations are available in different sorts of ceramics as well as composite. In order to bond restorations prepared out of composite blocks into tooth cavities, it is recommended to gently sandblast the surface prior to the application of a primer/adhesive. Today, the effect of sandblasting composite block surfaces has not thoroughly been investigated. In this study, the ultra-structure of composite CAD-CAM blocks was investigated with special attention to the effect of sandblasting on the surface topography and of silanization on the bonding performance. Five different composite CAD-CAM blocks were involved. We correlatively investigated their structural and chemical composition using X-ray diffraction (XRD), energy dispersion spectroscopy (EDS), scanning electron microscopy (SEM) and (scanning) transmission electron microscopy ((S)TEM). The effect of sandblasting was also imaged in cross-section and at the interface with composite cement. Finally, we measured the shear bond strength to the sandblasted block surface with and without silanization. All composite blocks revealed a different ultra-structure. Sandblasting increased surface roughness and resulted in an irregular surface with some filler exposure. Sandblasting also damaged the surface. When the sandblasted composite blocks were silanized, superior bonding receptiveness in terms of higher bond strength was achieved except for Shofu Block HC. Sandblasting followed by silanization improved the bond strength to composite CAD-CAM blocks. However, sandblasting may also damage the composite CAD-CAM block surface. For the composite CAD-CAM block Shofu Block HC, the damage was so severe that silanization did not improve bond strength. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Preparing Students for Computer Aided Drafting (CAD). A Conceptual Approach.

ERIC Educational Resources Information Center

Putnam, A. R.; Duelm, Brian

This presentation outlines guidelines for developing and implementing an introductory course in computer-aided drafting (CAD) that is geared toward secondary-level students. The first section of the paper, which deals with content identification and selection, includes lists of mechanical drawing and CAD competencies and a list of rationales for…

Observations of winds with an incoherent lidar detector

NASA Technical Reports Server (NTRS)

Abreu, Vincent J.; Barnes, John E.; Hays, Paul B.

1992-01-01

A Fabry-Perot interferometer and image-plane detector system to be used as a receiver for a Doppler lidar have been developed. This system incorporates the latest technology in multichannel detectors, and it is an important step toward the development of operational wind profiler systems for the atmosphere. The instrumentation includes a stable high-resolution optically contacted plane etalon and a multiring anode detector to scan the image plane of the Fabry-Perot interferometer spatially. The high wavelength resolution provided by the interferometer permits the aerosol and molecular components of the backscattered signal to be distinguished, and the Doppler shift of either component can then be used to determine the wind altitude profile. The receiver performance has been tested by measuring the wind profile in the boundary layer. The Fabry-Perot interferometer and image-plane detector characteristics are described and sample measurements are presented. The potential of the system as a wind profiler in the troposphere, the stratosphere, and the mesosphere is also considered.

Structure, functional characterization, and evolution of the dihydroorotase domain of human CAD.

PubMed

Grande-García, Araceli; Lallous, Nada; Díaz-Tejada, Celsa; Ramón-Maiques, Santiago

2014-02-04

Upregulation of CAD, the multifunctional protein that initiates and controls the de novo biosynthesis of pyrimidines in animals, is essential for cell proliferation. Deciphering the architecture and functioning of CAD is of interest for its potential usage as an antitumoral target. However, there is no detailed structural information about CAD other than that it self-assembles into hexamers of ∼1.5 MDa. Here we report the crystal structure and functional characterization of the dihydroorotase domain of human CAD. Contradicting all assumptions, the structure reveals an active site enclosed by a flexible loop with two Zn²⁺ ions bridged by a carboxylated lysine and a third Zn coordinating a rare histidinate ion. Site-directed mutagenesis and functional assays prove the involvement of the Zn and flexible loop in catalysis. Comparison with homologous bacterial enzymes supports a reclassification of the DHOase family and provides strong evidence against current models of the architecture of CAD. Copyright © 2014 Elsevier Ltd. All rights reserved.

Broadband measurements of aerosol extinction in the ultraviolet spectral region

NASA Astrophysics Data System (ADS)

Washenfelder, R. A.; Flores, J. M.; Brock, C. A.; Brown, S. S.; Rudich, Y.

2013-04-01

Aerosols influence the Earth's radiative budget by scattering and absorbing incoming solar radiation. The optical properties of aerosols vary as a function of wavelength, but few measurements have reported the wavelength dependence of aerosol extinction cross sections and complex refractive indices. We describe a new laboratory instrument to measure aerosol optical extinction as a function of wavelength, using cavity enhanced spectroscopy with a broadband light source. The instrument consists of two broadband channels which span the 360-390 and 385-420 nm spectral regions using two light emitting diodes (LED) and a grating spectrometer with charge-coupled device (CCD) detector. We determined aerosol extinction cross sections and directly observed Mie scattering resonances for aerosols that are purely scattering (polystyrene latex spheres and ammonium sulfate), slightly absorbing (Suwannee River fulvic acid), and strongly absorbing (nigrosin dye). We describe an approach for retrieving refractive indices as a function of wavelength from the measured extinction cross sections over the 360-420 nm wavelength region. The retrieved refractive indices for PSL and ammonium sulfate agree within uncertainty with the literature values for this spectral region. The refractive index determined for nigrosin is 1.78 (± 0.03) + 0.19 (± 0.08)i at 360 nm and 1.63 (± 0.03) + 0.21 (± 0.05)i at 420 nm. The refractive index determined for Suwannee River fulvic acid is 1.71 (± 0.02) + 0.07 (± 0.06)i at 360 nm and 1.66 (± 0.02) + 0.06 (± 0.04)i at 420 nm. These laboratory results support the potential for a field instrument capable of determining ambient aerosol optical extinction, average aerosol extinction cross section, and complex refractive index as a function of wavelength.

Broadband measurements of aerosol extinction in the ultraviolet spectral region

NASA Astrophysics Data System (ADS)

Washenfelder, R. A.; Flores, J. M.; Brock, C. A.; Brown, S. S.; Rudich, Y.

2013-01-01

Aerosols influence the Earth's radiative budget by scattering and absorbing incoming solar radiation. The optical properties of aerosols vary as a function of wavelength, but few measurements have reported the wavelength dependence of aerosol extinction cross-sections and complex refractive indices. We describe a new laboratory instrument to measure aerosol optical extinction as a function of wavelength, using cavity enhanced spectroscopy with a broadband light source. The instrument consists of two broadband channels which span the 360-390 and 385-420 nm spectral regions using two light emitting diodes (LED) and a grating spectrometer with charge-coupled device (CCD) detector. We determined aerosol extinction cross-sections and directly observed Mie scattering resonances for aerosols that are purely scattering (polystyrene latex spheres and ammonium sulfate), slightly absorbing (Suwannee River fulvic acid), and strongly absorbing (nigrosin dye). We describe an approach for retrieving refractive indices as a function of wavelength from the measured extinction cross-sections over the 360-420 nm wavelength region. The retrieved refractive indices for PSL and ammonium sulfate agree within uncertainty with literature values for this spectral region. The refractive index determined for nigrosin is 1.78 (±0.03) + 0.19 (±0.08) i at 360 nm and 1.53 (±0.03) + 0.21 (±0.05) i at 420 nm. The refractive index determined for Suwannee River fulvic acid is 1.71 (±0.02) + 0.07 (±0.06) i at 360 nm and 1.66 (±0.02) + 0.06 (±0.04) i at 420 nm. These laboratory results support the potential for a field instrument capable of determining ambient aerosol optical extinction, average aerosol extinction cross-section, and complex refractive index as a function of wavelength.

Do CAD/CAM dentures really release less monomer than conventional dentures?

PubMed

Steinmassl, Patricia-Anca; Wiedemair, Verena; Huck, Christian; Klaunzer, Florian; Steinmassl, Otto; Grunert, Ingrid; Dumfahrt, Herbert

2017-06-01

Computer-aided design (CAD)/computer-aided manufacturing (CAM) dentures are assumed to have more favourable material properties than conventionally fabricated dentures, among them a lower methacrylate monomer release. The aim of this study was to test this hypothesis. CAD/CAM dentures were generated from ten different master casts by using four different CAD/CAM systems. Conventional, heat-polymerised dentures served as control group. Denture weight and volume were measured; the density was calculated, and the denture surface area was assessed digitally. The monomer release after 7 days of water storage was measured by high-performance liquid chromatography. Whole You Nexteeth and Wieland Digital Dentures had significantly lower mean volume and weight than conventional dentures. Baltic Denture System and Whole You Nexteeth had a significantly increased density. Baltic Denture System had a significantly smaller surface area. None of the CAD/CAM dentures released significantly less monomer than the control group. All tested dentures released very low amounts of methacrylate monomer, but not significantly less than conventional dentures. A statistically significant difference might nevertheless exist in comparison to other, less recommendable denture base materials, such as the frequently used autopolymerising resins. CAD/CAM denture fabrication has numerous advantages. It enables the fabrication of dentures with lower resin volume and lower denture weight. Both could increase the patient comfort. Dentures with higher density might exhibit more favourable mechanical properties. The hypothesis that CAD/CAM dentures release less monomer than conventional dentures could, however, not be verified.

Automatic image database generation from CAD for 3D object recognition

NASA Astrophysics Data System (ADS)

Sardana, Harish K.; Daemi, Mohammad F.; Ibrahim, Mohammad K.

1993-06-01

The development and evaluation of Multiple-View 3-D object recognition systems is based on a large set of model images. Due to the various advantages of using CAD, it is becoming more and more practical to use existing CAD data in computer vision systems. Current PC- level CAD systems are capable of providing physical image modelling and rendering involving positional variations in cameras, light sources etc. We have formulated a modular scheme for automatic generation of various aspects (views) of the objects in a model based 3-D object recognition system. These views are generated at desired orientations on the unit Gaussian sphere. With a suitable network file sharing system (NFS), the images can directly be stored on a database located on a file server. This paper presents the image modelling solutions using CAD in relation to multiple-view approach. Our modular scheme for data conversion and automatic image database storage for such a system is discussed. We have used this approach in 3-D polyhedron recognition. An overview of the results, advantages and limitations of using CAD data and conclusions using such as scheme are also presented.

Computer-aided-diagnosis (CAD) for colposcopy

NASA Astrophysics Data System (ADS)

Lange, Holger; Ferris, Daron G.

2005-04-01

Uterine cervical cancer is the second most common cancer among women worldwide. Colposcopy is a diagnostic method, whereby a physician (colposcopist) visually inspects the lower genital tract (cervix, vulva and vagina), with special emphasis on the subjective appearance of metaplastic epithelium comprising the transformation zone on the cervix. Cervical cancer precursor lesions and invasive cancer exhibit certain distinctly abnormal morphologic features. Lesion characteristics such as margin; color or opacity; blood vessel caliber, intercapillary spacing and distribution; and contour are considered by colposcopists to derive a clinical diagnosis. Clinicians and academia have suggested and shown proof of concept that automated image analysis of cervical imagery can be used for cervical cancer screening and diagnosis, having the potential to have a direct impact on improving women"s health care and reducing associated costs. STI Medical Systems is developing a Computer-Aided-Diagnosis (CAD) system for colposcopy -- ColpoCAD. At the heart of ColpoCAD is a complex multi-sensor, multi-data and multi-feature image analysis system. A functional description is presented of the envisioned ColpoCAD system, broken down into: Modality Data Management System, Image Enhancement, Feature Extraction, Reference Database, and Diagnosis and directed Biopsies. The system design and development process of the image analysis system is outlined. The system design provides a modular and open architecture built on feature based processing. The core feature set includes the visual features used by colposcopists. This feature set can be extended to include new features introduced by new instrument technologies, like fluorescence and impedance, and any other plausible feature that can be extracted from the cervical data. Preliminary results of our research on detecting the three most important features: blood vessel structures, acetowhite regions and lesion margins are shown. As this is a new

21 CFR 872.3661 - Optical Impression Systems for CAD/CAM.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Optical Impression Systems for CAD/CAM. 872.3661 Section 872.3661 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Design and Manufacturing (CAD/CAM) of Dental Restorations; Guidance for Industry and FDA.” For the...

Discoloration of various CAD/CAM blocks after immersion in coffee.

PubMed

Lauvahutanon, Sasipin; Shiozawa, Maho; Takahashi, Hidekazu; Iwasaki, Naohiko; Oki, Meiko; Finger, Werner J; Arksornnukit, Mansuang

2017-02-01

This study evaluated color differences (Δ E s) and translucency parameter changes (Δ TP s) of various computer-aided design/computer-aided manufacturing (CAD/CAM) blocks after immersion in coffee. Eight CAD/CAM blocks and four restorative composite resins were evaluated. The CIE L * a * b * values of 2.0 mm thick disk-shaped specimens were measured using the spectrophotometer on white and black backgrounds ( n = 6). The Δ E s and Δ TP s of one day, one week, and one month immersion in coffee or water were calculated. The values of each material were analyzed by two-way ANOVA and Tukey's multiple comparisons (α = 0.05). The Δ E s after prophylaxis paste polishing of 1 month coffee immersion specimens, water sorption and solubility were also evaluated. After one month in coffee, Δ E s of CAD/CAM composite resin blocks and restorative composites ranged from 1.6 to 3.7 and from 2.1 to 7.9, respectively, and Δ TP s decreased. The ANOVA of Δ E s and Δ TP s revealed significant differences in two main factors, immersion periods and media, and their interaction except for Δ E s of TEL (Telio CAD, Ivoclar Vivadent). The Δ E s significantly decreased after prophylaxis polishing except GRA (Gradia Block, GC). There was no significant correlation between Δ E s and water sorption or solubility in water. The Δ E s of CAD/CAM blocks after immersion in coffee varied among products and were comparable to those of restorative composite resins. The discoloration of CAD/CAM composite resin blocks could be effectively removed with prophylaxis paste polishing, while that of some restorative composites could not be removed.

Quantitative assessment of multiple sclerosis lesion load using CAD and expert input

NASA Astrophysics Data System (ADS)

Gertych, Arkadiusz; Wong, Alexis; Sangnil, Alan; Liu, Brent J.

2008-03-01

Multiple sclerosis (MS) is a frequently encountered neurological disease with a progressive but variable course affecting the central nervous system. Outline-based lesion quantification in the assessment of lesion load (LL) performed on magnetic resonance (MR) images is clinically useful and provides information about the development and change reflecting overall disease burden. Methods of LL assessment that rely on human input are tedious, have higher intra- and inter-observer variability and are more time-consuming than computerized automatic (CAD) techniques. At present it seems that methods based on human lesion identification preceded by non-interactive outlining by CAD are the best LL quantification strategies. We have developed a CAD that automatically quantifies MS lesions, displays 3-D lesion map and appends radiological findings to original images according to current DICOM standard. CAD is also capable to display and track changes and make comparison between patient's separate MRI studies to determine disease progression. The findings are exported to a separate imaging tool for review and final approval by expert. Capturing and standardized archiving of manual contours is also implemented. Similarity coefficients calculated from quantities of LL in collected exams show a good correlation of CAD-derived results vs. those incorporated as expert's reading. Combining the CAD approach with an expert interaction may impact to the diagnostic work-up of MS patients because of improved reproducibility in LL assessment and reduced time for single MR or comparative exams reading. Inclusion of CAD-generated outlines as DICOM-compliant overlays into the image data can serve as a better reference in MS progression tracking.

The Nucleotide Synthesis Enzyme CAD Inhibits NOD2 Antibacterial Function in Human Intestinal Epithelial Cells

PubMed Central

Richmond, Amy L.; Kabi, Amrita; Homer, Craig R.; García, Noemí Marina; Nickerson, Kourtney P.; NesvizhskiI, Alexey I.; Sreekumar, Arun; Chinnaiyan, Arul M.; Nuñez, Gabriel; McDonald, Christine

2013-01-01

BACKGROUND & AIMS Polymorphisms that reduce the function of nucleotide-binding oligomerization domain (NOD)2, a bacterial sensor, have been associated with Crohn’s disease (CD). No proteins that regulate NOD2 activity have been identified as selective pharmacologic targets. We sought to discover regulators of NOD2 that might be pharmacologic targets for CD therapies. METHODS Carbamoyl phosphate synthetase/ aspartate transcarbamylase/dihydroorotase (CAD) is an enzyme required for de novo pyrimidine nucleotide synthesis; it was identified as a NOD2-interacting protein by immunoprecipitation-coupled mass spectrometry. CAD expression was assessed in colon tissues from individuals with and without inflammatory bowel disease by immunohistochemistry. The interaction between CAD and NOD2 was assessed in human HCT116 intestinal epithelial cells by immunoprecipitation, immunoblot, reporter gene, and gentamicin protection assays. We also analyzed human cell lines that express variants of NOD2 and the effects of RNA interference, overexpression and CAD inhibitors. RESULTS CAD was identified as a NOD2-interacting protein expressed at increased levels in the intestinal epithelium of patients with CD compared with controls. Overexpression of CAD inhibited NOD2-dependent activation of nuclear factor κB and p38 mitogen-activated protein kinase, as well as intracellular killing of Salmonella. Reduction of CAD expression or administration of CAD inhibitors increased NOD2-dependent signaling and antibacterial functions of NOD2 variants that are and are not associated with CD. CONCLUSIONS The nucleotide synthesis enzyme CAD is a negative regulator of NOD2. The antibacterial function of NOD2 variants that have been associated with CD increased in response to pharmacologic inhibition of CAD. CAD is a potential therapeutic target for CD. PMID:22387394

Creation of Anatomically Accurate Computer-Aided Design (CAD) Solid Models from Medical Images

NASA Technical Reports Server (NTRS)

Stewart, John E.; Graham, R. Scott; Samareh, Jamshid A.; Oberlander, Eric J.; Broaddus, William C.

1999-01-01

Most surgical instrumentation and implants used in the world today are designed with sophisticated Computer-Aided Design (CAD)/Computer-Aided Manufacturing (CAM) software. This software automates the mechanical development of a product from its conceptual design through manufacturing. CAD software also provides a means of manipulating solid models prior to Finite Element Modeling (FEM). Few surgical products are designed in conjunction with accurate CAD models of human anatomy because of the difficulty with which these models are created. We have developed a novel technique that creates anatomically accurate, patient specific CAD solids from medical images in a matter of minutes.

Fatigue Resistance of CAD/CAM Resin Composite Molar Crowns

PubMed Central

Shembish, Fatma A.; Tong, Hui; Kaizer, Marina; Janal, Malvin N.; Thompson, Van P.; Opdam, Niek J.; Zhang, Yu

2016-01-01

Objective To demonstrate the fatigue behavior of CAD/CAM resin composite molar crowns using a mouth-motion step-stress fatigue test. Monolithic leucite-reinforced glass-ceramic crowns were used as a reference. Methods Fully anatomically shaped monolithic resin composite molar crowns (Lava Ultimate, n = 24) and leucite reinforced glass-ceramic crowns (IPS Empress CAD, n = 24) were fabricated using CAD/CAM systems. Crowns were cemented on aged dentin-like resin composite tooth replicas (Filtek Z100) with resin-based cements (RelyX Ultimate for Lava Ultimate or Multilink Automix for IPS Empress). Three step-stress profiles (aggressive, moderate and mild) were employed for the accelerated sliding-contact mouth-motion fatigue test. Twenty one crowns from each group were randomly distributed among these three profiles (1:2:4). Failure was designated as chip-off or bulk fracture. Optical and electronic microscopes were used to examine the occlusal surface and subsurface damages, as well as the material microstructures. Results The resin composite crowns showed only minor occlusal damage during mouth-motion step-stress fatigue loading up to 1700 N. Cross-sectional views revealed contact-induced cone cracks in all specimens, and flexural radial cracks in 2 crowns. Both cone and radial cracks were relatively small compared to the crown thickness. Extending these cracks to the threshold for catastrophic failure would require much higher indentation loads or more loading cycles. In contrast, all of the glass-ceramic crowns fractured, starting at loads of approximately 450 N. Significance Monolithic CAD/CAM resin composite crowns endure, with only superficial damage, fatigue loads 3 – 4 times higher than those causing catastrophic failure in glass-ceramic CAD crowns. PMID:26777092

Microcomputer Simulated CAD for Engineering Graphics.

ERIC Educational Resources Information Center

Huggins, David L.; Myers, Roy E.

1983-01-01

Describes a simulated computer-aided-graphics (CAD) program at The Pennsylvania State University. Rationale for the program, facilities, microcomputer equipment (Apple) used, and development of a software package for simulating applied engineering graphics are considered. (JN)

Lidar sprectroscopy instrument (LISSI): An infrastructure facility for chemical aerosol profiling at the University of Hertfordshire

NASA Astrophysics Data System (ADS)

Tesche, Matthias; Tatarov, Boyan; Noh, Youngmin; Müller, Detlef

2018-04-01

The lidar development at the University of Hertfordshire explores the feasibility of using Raman backscattering for chemical aerosol profiling. This paper provides an overview of the new facility. A high-power Nd:YAG/OPO setup is used to excite Raman backscattering at a wide range of wavelengths. The receiver combines a spectrometer with a 32-channel detector or an ICCD camera to resolve Raman signals of various chemical compounds. The new facility will open new avenues for chemical profiling of aerosol pollution from measurements of Raman scattering by selected chemical compounds, provide data that allow to close the gap between optical and microphysical aerosol profiling with lidar and enables connecting lidar measurements to parameters used in atmospheric modelling.

HDL subfractions and very early CAD: novel findings from untreated patients in a Chinese cohort.

PubMed

Zhang, Yan; Zhu, Cheng-Gang; Xu, Rui-Xia; Li, Sha; Li, Xiao-Lin; Guo, Yuan-Lin; Wu, Na-Qiong; Gao, Ying; Qing, Ping; Cui, Chuan-Jue; Sun, Jing; Li, Jian-Jun

2016-08-04

Coronary artery disease (CAD) in very young individuals is a rare disease associated with poor prognosis. However, the role of specific lipoprotein subfractions in very young CAD patients (≤45 years) is not established yet. A total of 734 consecutive CAD subjects were enrolled and were classified as very early (n = 81, ≤45), early (n = 304, male: 45-55; female: 45-65), and late (n = 349, male: >55; female: >65) groups. Meanwhile, a group of non-CAD subjects were also enrolled as controls (n = 56, ≤45). The lipoprotein separation was performed using Lipoprint System. As a result, the very early CAD patients have lower large high-density lipoprotein (HDL) subfraction and higher small low-density lipoprotein (LDL) subfraction (p < 0.05). Although body mass index was inversely related to large HDL subfraction, overweight did not influence its association with very early CAD. In the logistic regression analysis, large HDL was inversely [OR 95% CI: 0.872 (0.825-0.922)] while small LDL was positively [1.038 (1.008-1.069)] related to very early CAD. However, after adjusting potential confounders, the association was only significant for large HDL [0.899 (0.848-0.954)]. This study firstly demonstrated that large HDL subfraction was negatively related to very early CAD suggestive of its important role in very early CAD incidence.

Computer-aided detection (CAD) of breast cancer on full field digital and screening film mammograms

NASA Astrophysics Data System (ADS)

Sun, Xuejun; Qian, Wei; Song, Xiaoshan; Qian, Yuyan; Song, Dansheng; Clark, Robert A.

2003-05-01

Full-field digital mammography (FFDM) as a new breast imaging modality has potential to detect more breast cancers or to detect them at smaller sizes and earlier stages compared with screening film mammography (SFM). However, its performance needs verification, and it would pose new problems for the development of CAD methods for breast cancer detection and diagnosis. Performance evaluation of CAD systems on FFDM and SFM has been conducted in this study, respectively. First, an adaptive CAD system employing a series of advanced modules has been developed on FFDM. Second, a standardization approach has been developed to make the CAD system independent of characteristics of digitizer or imaging modalities for mammography. CAD systems developed previously for SFM and developed in this study for FFDM have been evaluated on FFDM and SFM images without and with standardization, respectively, to examine the performance improvement of the CAD system developed in this study. Computerized free-response receiver operating characteristic (FROC) analysis has been adopted as performance evaluation method. Compared with previous one, the CAD system developed in this study demonstrated significantly performance improvements. However, the comparison results have shown that the performances of final CAD system in this study are not significantly different on FFDM and on SFM after standardization. It needs further study on the assessment of CAD system performance on FFDM and SFM modalities.

A Step-by-Step Conservative Approach for CAD-CAM Laminate Veneers

PubMed Central

Henríquez Gutiérrez, Ismael; Guzmán Marusic, Álvaro; Báez Rosales, Abelardo; Tisi Lanchares, José Pablo

2017-01-01

The use of CAD/CAM technology has allowed the fabrication of ceramic restorations efficiently and with predictable results. Lithium disilicate is a type of glass ceramic material that can be used for the elaboration of laminate veneers, being monolithic restorations which require characterization through a covering ceramic in order to achieve acceptable esthetic results. The next case report shows a predictable clinical protocol for the rehabilitation of the anterior teeth through the preparation of CAD/CAM veneers (e.max CAD, Ivoclar Vivadent, Liechtenstein) which have been characterized by a nanofluorapatite ceramic (e.max Ceram, Ivoclar Vivadent, Liechtenstein) through the layering technique. PMID:28884029

Design of Complete Dentures by Adopting CAD Developed for Fixed Prostheses.

PubMed

Li, Yanfeng; Han, Weili; Cao, Jing; Iv, Yuan; Zhang, Yue; Han, Yishi; Shen, Yi; Ma, Zheng; Liu, Huanyue

2018-02-01

The demand for complete dentures is expected to increase worldwide, but complete dentures are mainly designed and fabricated manually involving a broad series of clinical and laboratory procedures. Therefore, the quality of complete dentures largely depends on the skills of the dentist and technician, leading to difficulty in quality control. Computer-aided design and manufacturing (CAD/CAM) has been used to design and fabricate various dental restorations including dental inlays, veneers, crowns, partial crowns, and fixed partial dentures (FPDs). It has been envisioned that the application of CAD/CAM technology could reduce intensive clinical/laboratory work for the fabrication of complete dentures; however, CAD/CAM is seldom used to fabricate complete dentures due to the lack of suitable CAD software to design virtual complete dentures although the CAM techniques are in a much advanced stage. Here we report the successful design of virtual complete dentures using CAD software of 3Shape Dental System 2012, which was developed for designing fixed prostheses instead of complete dentures. Our results demonstrated that complete dentures could be successfully designed by the combination of two modeling processes, single coping and full anatomical FPD, available in the 3Shape Dental System 2012. © 2016 by the American College of Prosthodontists.

BioNetCAD: design, simulation and experimental validation of synthetic biochemical networks

PubMed Central

Rialle, Stéphanie; Felicori, Liza; Dias-Lopes, Camila; Pérès, Sabine; El Atia, Sanaâ; Thierry, Alain R.; Amar, Patrick; Molina, Franck

2010-01-01

Motivation: Synthetic biology studies how to design and construct biological systems with functions that do not exist in nature. Biochemical networks, although easier to control, have been used less frequently than genetic networks as a base to build a synthetic system. To date, no clear engineering principles exist to design such cell-free biochemical networks. Results: We describe a methodology for the construction of synthetic biochemical networks based on three main steps: design, simulation and experimental validation. We developed BioNetCAD to help users to go through these steps. BioNetCAD allows designing abstract networks that can be implemented thanks to CompuBioTicDB, a database of parts for synthetic biology. BioNetCAD enables also simulations with the HSim software and the classical Ordinary Differential Equations (ODE). We demonstrate with a case study that BioNetCAD can rationalize and reduce further experimental validation during the construction of a biochemical network. Availability and implementation: BioNetCAD is freely available at http://www.sysdiag.cnrs.fr/BioNetCAD. It is implemented in Java and supported on MS Windows. CompuBioTicDB is freely accessible at http://compubiotic.sysdiag.cnrs.fr/ Contact: stephanie.rialle@sysdiag.cnrs.fr; franck.molina@sysdiag.cnrs.fr Supplementary information: Supplementary data are available at Bioinformatics online. PMID:20628073

Classifying aerosol type using in situ surface spectral aerosol optical properties

NASA Astrophysics Data System (ADS)

Schmeisser, Lauren; Andrews, Elisabeth; Ogren, John A.; Sheridan, Patrick; Jefferson, Anne; Sharma, Sangeeta; Kim, Jeong Eun; Sherman, James P.; Sorribas, Mar; Kalapov, Ivo; Arsov, Todor; Angelov, Christo; Mayol-Bracero, Olga L.; Labuschagne, Casper; Kim, Sang-Woo; Hoffer, András; Lin, Neng-Huei; Chia, Hao-Ping; Bergin, Michael; Sun, Junying; Liu, Peng; Wu, Hao

2017-10-01

Knowledge of aerosol size and composition is important for determining radiative forcing effects of aerosols, identifying aerosol sources and improving aerosol satellite retrieval algorithms. The ability to extrapolate aerosol size and composition, or type, from intensive aerosol optical properties can help expand the current knowledge of spatiotemporal variability in aerosol type globally, particularly where chemical composition measurements do not exist concurrently with optical property measurements. This study uses medians of the scattering Ångström exponent (SAE), absorption Ångström exponent (AAE) and single scattering albedo (SSA) from 24 stations within the NOAA/ESRL Federated Aerosol Monitoring Network to infer aerosol type using previously published aerosol classification schemes.Three methods are implemented to obtain a best estimate of dominant aerosol type at each station using aerosol optical properties. The first method plots station medians into an AAE vs. SAE plot space, so that a unique combination of intensive properties corresponds with an aerosol type. The second typing method expands on the first by introducing a multivariate cluster analysis, which aims to group stations with similar optical characteristics and thus similar dominant aerosol type. The third and final classification method pairs 3-day backward air mass trajectories with median aerosol optical properties to explore the relationship between trajectory origin (proxy for likely aerosol type) and aerosol intensive parameters, while allowing for multiple dominant aerosol types at each station.The three aerosol classification methods have some common, and thus robust, results. In general, estimating dominant aerosol type using optical properties is best suited for site locations with a stable and homogenous aerosol population, particularly continental polluted (carbonaceous aerosol), marine polluted (carbonaceous aerosol mixed with sea salt) and continental dust/biomass sites

On the Use of CAD and Cartesian Methods for Aerodynamic Optimization

NASA Technical Reports Server (NTRS)

Nemec, M.; Aftosmis, M. J.; Pulliam, T. H.

2004-01-01

The objective for this paper is to present the development of an optimization capability for Curt3D, a Cartesian inviscid-flow analysis package. We present the construction of a new optimization framework and we focus on the following issues: 1) Component-based geometry parameterization approach using parametric-CAD models and CAPRI. A novel geometry server is introduced that addresses the issue of parallel efficiency while only sparingly consuming CAD resources; 2) The use of genetic and gradient-based algorithms for three-dimensional aerodynamic design problems. The influence of noise on the optimization methods is studied. Our goal is to create a responsive and automated framework that efficiently identifies design modifications that result in substantial performance improvements. In addition, we examine the architectural issues associated with the deployment of a CAD-based approach in a heterogeneous parallel computing environment that contains both CAD workstations and dedicated compute engines. We demonstrate the effectiveness of the framework for a design problem that features topology changes and complex geometry.

Two-body wear rate of CAD/CAM resin blocks and their enamel antagonists.

PubMed

Stawarczyk, Bogna; Özcan, Mutlu; Trottmann, Albert; Schmutz, Felix; Roos, Malgorzata; Hämmerle, Christoph

2013-05-01

Computer-aided design and computer-aided manufacturing (CAD/CAM) resins exhibit good mechanical properties and can be used as long-term restorations. The wear rate of such resins and their enamel antagonists is unknown. The purpose of this study was to test and compare the 2-body wear rate of CAD/CAM resin blocks. Wear specimens (N=42, n=6) were made from 5 CAD/CAM resins: ZENO PMMA (ZP), artBloc Temp (AT), Telio CAD (TC), Blanc High-class (HC), CAD-Temp (CT); 1 manually polymerized resin: Integral esthetic press (negative control group, IEP); and 1 glass-ceramic: VITA Mark II (positive control group, VM2). The specimens for the wear resistance were aged in a thermomechanical loading machine (49 N, 1.67 Hz, 5/50°C) with human enamel antagonists. The material loss of all specimens before, during, and after aging was evaluated with a 3DS profilometer. The measured material loss data of all tested groups were statistically evaluated with linear mixed model analysis (a=.05). Manually polymerized resin showed significantly higher material wear (P<.001) than all other tested groups. Glass-ceramic showed significantly lower wear values (P<.001) than CAD/CAM resins ZP, AT, HC, CT, and IES. CAD/CAM resin TC was not significantly different from the positive control group. Glass-ceramic showed the highest enamel wear values (P<.001) of all tested resins. No differences were found in the enamel wear among all resins. The glass-ceramic group showed damage in the form of cracks on the worn enamel surface in 50% of specimens. CAD/CAM resins showed lower wear rates than those conventionally polymerized. Only one CAD/CAM resin, TC, presented material wear values comparable with glass-ceramic. The tested glass-ceramic developed cracks in the enamel antagonist and showed the highest enamel wear values of all other tested groups. Copyright © 2013 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

Distortion of CAD-CAM-fabricated implant-fixed titanium and zirconia complete dental prosthesis frameworks.

PubMed

Al-Meraikhi, Hadi; Yilmaz, Burak; McGlumphy, Edwin; Brantley, William A; Johnston, William M

2018-01-01

Computer-aided design and computer-aided manufacturing (CAD-CAM)-fabricated titanium and zirconia implant-supported fixed dental prostheses have become increasingly popular for restoring patients with complete edentulism. However, the distortion level of these frameworks is not well known. The purpose of this in vitro study was to compare the 3-dimensional (3D) distortion of CAD-CAM zirconia and titanium implant-fixed screw-retained complete dental prostheses. A master edentulous model with 4 implants at the positions of the maxillary first molars and canines was used. Multiunit abutments (Nobel Biocare) secured to the model were digitally scanned using scan bodies and a laboratory scanner (S600 ARTI; Zirkonzahn). Titanium (n=5) and zirconia (n=5) frameworks were milled using a CAD-CAM system (Zirkonzahn M1; Zirkonzahn). All frameworks were scanned using an industrial computed tomography (CT) scanner (Nikon/X-Tek XT H 225kV MCT Micro-Focus). The direct CT scans were reconstructed to generate standard tessellation language (STL) files. To calculate the 3D distortion of the frameworks, STL files of the CT scans were aligned to the CAD model using a sum of the least squares best-fit algorithm. Surface comparison points were placed on the CAD model on the midfacial aspect of all teeth. The 3D distortion of each direct scan to the CAD model was calculated. In addition, color maps of the scan-to-CAD comparison were constructed using a ±0.500 mm color scale range. Both materials exhibited distortion; however, no significant difference was found in the amount of distortion from the CAD model between the materials (P=.747). Absolute values of deviations from the CAD model were evident in the x and y plane and less so in the z direction. Zirconia and titanium frameworks showed similar 3D distortion compared with the CAD model for the tested CAD-CAM and implant systems. The distortion was more pronounced in the horizontal and sagittal plane than in the vertical plane

When and why might a Computer Aided Detection (CAD) system interfere with visual search? An eye-tracking study

PubMed Central

Drew, Trafton; Cunningham, Corbin; Wolfe, Jeremy

2012-01-01

Rational and Objectives Computer Aided Detection (CAD) systems are intended to improve performance. This study investigates how CAD might actually interfere with a visual search task. This is a laboratory study with implications for clinical use of CAD. Methods 47 naïve observers in two studies were asked to search for a target, embedded in 1/f2.4 noise while we monitored their eye-movements. For some observers, a CAD system marked 75% of targets and 10% of distractors while other observers completed the study without CAD. In Experiment 1, the CAD system’s primary function was to tell observers where the target might be. In Experiment 2, CAD provided information about target identity. Results In Experiment 1, there was a significant enhancement of observer sensitivity in the presence of CAD (t(22)=4.74, p<.001), but there was also a substantial cost. Targets that were not marked by the CAD system were missed more frequently than equivalent targets in No CAD blocks of the experiment (t(22)=7.02, p<.001). Experiment 2 showed no behavioral benefit from CAD, but also no significant cost on sensitivity to unmarked targets (t(22)=0.6, p=n.s.). Finally, in both experiments, CAD produced reliable changes in eye-movements: CAD observers examined a lower total percentage of the search area than the No CAD observers (Ex 1: t(48)=3.05, p<.005; Ex 2: t(50)=7.31, p<.001). Conclusions CAD signals do not combine with observers’ unaided performance in a straight-forward manner. CAD can engender a sense of certainty that can lead to incomplete search and elevated chances of missing unmarked stimuli. PMID:22958720

On the Use of CAD-Native Predicates and Geometry in Surface Meshing

NASA Technical Reports Server (NTRS)

Aftosmis, M. J.

1999-01-01

Several paradigms for accessing computer-aided design (CAD) geometry during surface meshing for computational fluid dynamics are discussed. File translation, inconsistent geometry engines, and nonnative point construction are all identified as sources of nonrobustness. The paper argues in favor of accessing CAD parts and assemblies in their native format, without translation, and for the use of CAD-native predicates and constructors in surface mesh generation. The discussion also emphasizes the importance of examining the computational requirements for exact evaluation of triangulation predicates during surface meshing.

CAD-Based Aerodynamic Design of Complex Configurations using a Cartesian Method

NASA Technical Reports Server (NTRS)

Nemec, Marian; Aftosmis, Michael J.; Pulliam, Thomas H.

2003-01-01

A modular framework for aerodynamic optimization of complex geometries is developed. By working directly with a parametric CAD system, complex-geometry models are modified nnd tessellated in an automatic fashion. The use of a component-based Cartesian method significantly reduces the demands on the CAD system, and also provides for robust and efficient flowfield analysis. The optimization is controlled using either a genetic or quasi-Newton algorithm. Parallel efficiency of the framework is maintained even when subject to limited CAD resources by dynamically re-allocating the processors of the flow solver. Overall, the resulting framework can explore designs incorporating large shape modifications and changes in topology.

Marginal and internal fit of nano-composite CAD/CAM restorations.

PubMed

Park, So-Hyun; Yoo, Yeon-Jee; Shin, Yoo-Jin; Cho, Byeong-Hoon; Baek, Seung-Ho

2016-02-01

The purpose of this study was to compare the marginal and internal fit of nano-composite CAD-CAM restorations. A full veneer crown and an mesio-occluso-distal (MOD) inlay cavity, which were prepared on extracted human molars, were used as templates of epoxy resin replicas. The prepared teeth were scanned and CAD-CAM restorations were milled using Lava Ultimate (LU) and experimental nano-composite CAD/CAM blocks (EB) under the same milling parameters. To assess the marginal and internal fit, the restorations were cemented to replicas and were embedded in an acrylic mold for sectioning at 0.5 mm intervals. The measured gap data were pooled according to the block types and measuring points for statistical analysis. Both the block type and measuring point significantly affected gap values, and their interaction was significant (p = 0.000). In crowns and inlays made from the two blocks, gap values were significantly larger in the occlusal area than in the axial area, while gap values in the marginal area were smallest (p < 0.001). Among the blocks, the restorations milled from EB had a significantly larger gap at all measuring points than those milled from LU (p = 0.000). The marginal and internal gaps of the two nano-composite CAD/CAM blocks differed according to the measuring points. Among the internal area of the two nano-composite CAD/CAM restorations, occlusal gap data were significantly larger than axial gap data. The EB crowns and inlays had significantly larger gaps than LU restorations.

Marginal and internal fit of nano-composite CAD/CAM restorations

PubMed Central

Park, So-Hyun; Shin, Yoo-Jin

2016-01-01

Objectives The purpose of this study was to compare the marginal and internal fit of nano-composite CAD-CAM restorations. Materials and Methods A full veneer crown and an mesio-occluso-distal (MOD) inlay cavity, which were prepared on extracted human molars, were used as templates of epoxy resin replicas. The prepared teeth were scanned and CAD-CAM restorations were milled using Lava Ultimate (LU) and experimental nano-composite CAD/CAM blocks (EB) under the same milling parameters. To assess the marginal and internal fit, the restorations were cemented to replicas and were embedded in an acrylic mold for sectioning at 0.5 mm intervals. The measured gap data were pooled according to the block types and measuring points for statistical analysis. Results Both the block type and measuring point significantly affected gap values, and their interaction was significant (p = 0.000). In crowns and inlays made from the two blocks, gap values were significantly larger in the occlusal area than in the axial area, while gap values in the marginal area were smallest (p < 0.001). Among the blocks, the restorations milled from EB had a significantly larger gap at all measuring points than those milled from LU (p = 0.000). Conclusions The marginal and internal gaps of the two nano-composite CAD/CAM blocks differed according to the measuring points. Among the internal area of the two nano-composite CAD/CAM restorations, occlusal gap data were significantly larger than axial gap data. The EB crowns and inlays had significantly larger gaps than LU restorations. PMID:26877989

Different CAD/CAM-processing routes for zirconia restorations: influence on fitting accuracy.

PubMed

Kohorst, Philipp; Junghanns, Janet; Dittmer, Marc P; Borchers, Lothar; Stiesch, Meike

2011-08-01

The aim of the present in vitro study was to evaluate the influence of different processing routes on the fitting accuracy of four-unit zirconia fixed dental prostheses (FDPs) fabricated by computer-aided design/computer-aided manufacturing (CAD/CAM). Three groups of zirconia frameworks with ten specimens each were fabricated. Frameworks of one group (CerconCAM) were produced by means of a laboratory CAM-only system. The other frameworks were made with different CAD/CAM systems; on the one hand by in-laboratory production (CerconCAD/CAM) and on the other hand by centralized production in a milling center (Compartis) after forwarding geometrical data. Frameworks were then veneered with the recommended ceramics, and marginal accuracy was determined using a replica technique. Horizontal marginal discrepancy, vertical marginal discrepancy, absolute marginal discrepancy, and marginal gap were evaluated. Statistical analyses were performed by one-way analysis of variance (ANOVA), with the level of significance chosen at 0.05. Mean horizontal discrepancies ranged between 22 μm (CerconCAM) and 58 μm (Compartis), vertical discrepancies ranged between 63 μm (CerconCAD/CAM) and 162 μm (CerconCAM), and absolute marginal discrepancies ranged between 94 μm (CerconCAD/CAM) and 181 μm (CerconCAM). The marginal gap varied between 72 μm (CerconCAD/CAM) and 112 μm (CerconCAM, Compartis). Statistical analysis revealed that, with all measurements, the marginal accuracy of the zirconia FDPs was significantly influenced by the processing route used (p < 0.05). Within the limitations of this study, all restorations showed a clinically acceptable marginal accuracy; however, the results suggest that the CAD/CAM systems are more precise than the CAM-only system for the manufacture of four-unit FDPs.

Edge strength of CAD/CAM materials.

PubMed

Pfeilschifter, Maria; Preis, Verena; Behr, Michael; Rosentritt, Martin

2018-05-16

To investigate the edge force of CAD/CAM materials as a function of (a) material, (b) thickness, and (c) distance from the margin. Materials intended for processing with CAD/CAM were investigated: eight resin composites, one resin-infiltrated ceramic, and a clinically proven lithiumdisilicate ceramic (reference). To measure edge force (that is, load to failure/crack), plates (d = 1 mm) were fixed and loaded with a Vickers diamond indenter (1 mm/min, Zwick 1446) at a distance of 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1.0 mm from the edge. Edge force was defined as a loading force at a distance of 0.5 mm. The type of failure was determined. To investigate the influence of the thickness, all data were determined on 1-mm and 2-mm plates. To test the influence of bonding and an underlying dentin, individual 1-mm plates were bonded to a 1-mm-thick dentin-like (concerning modulus of elasticity) resin composite. For the 1-mm plates, edge force varied between 64.4 ± 24.2 N (Shofu Block HC) and 183.2 ± 63.3 N (ceramic reference), with significant (p ≤ 0.001) differences between the materials. For the 2-mm plates, values between 129.2 ± 32.5 N (Lava Ultimate) and 230.3 ± 67.5 N (Cerasmart) were found. Statistical comparison revealed no significant differences (p > 0.109) between the materials. Brilliant Crios (p = 0.023), Enamic (p = 0.000), Shofu Blocks HC (p = 0.009), and Grandio Bloc (p = 0.002) showed significantly different edge force between the 1-mm- and 2-mm-thick plates. The failure pattern was either cracking, (severe) chipping, or fracture. Material, material thickness, and distance from the edge impact the edge force of CAD/CAM materials. CAD/CAM materials should be carefully selected on the basis of their individual edge force and performance during milling. Copyright © 2018 Elsevier Ltd. All rights reserved.

Impact of IPAD on CAD/CAM database university research

NASA Technical Reports Server (NTRS)

Leach, L. M.; Wozny, M. J.

1984-01-01

IPAD program has provided direction, focus and software products which impacted on CAD/CAM data base research and follow-on research. The relationship of IPAD to the research projects which involve the storage of geometric data in common data ase facilities such as data base machines, the exchange of data between heterogeneous data bases, the development of IGES processors, the migration of lrge CAD/CAM data base management systems to noncompatible hosts, and the value of RIM as a research tool is described.

Light-Absorbing Brown Carbon Aerosol Constituents from Combustion of Indonesian Peat and Biomass.

PubMed

Budisulistiorini, Sri Hapsari; Riva, Matthieu; Williams, Michael; Chen, Jing; Itoh, Masayuki; Surratt, Jason D; Kuwata, Mikinori

2017-04-18

Light-absorbing brown carbon (BrC) constituents of organic aerosol (OA) have been shown to significantly absorb ultraviolet (UV) and visible light and thus impact radiative forcing. However, molecular identification of the BrC constituents is still limited. In this study, we characterize BrC constituents at the molecular level in (i) aerosols emitted by combustion of peat, fern/leaf, and charcoal from Indonesia and (ii) ambient aerosols collected in Singapore during the 2015 haze episode. Aerosols were analyzed using ultra performance liquid chromatography instrument interfaced to a diode array detector and electrospray ionization high-resolution quadrupole time-of-flight mass spectrometer operated in the negative ion mode. In the laboratory-generated aerosols, we identified 41 compounds that can potentially absorb near-UV and visible wavelengths, such as oxygenated-conjugated compounds, nitroaromatics, and S-containing compounds. The sum of BrC constituents in peat, fern/leaf, and charcoal burning aerosols are 16%, 35%, and 28% of the OA mass, respectively, giving an average contribution of 24%. On average, the BrC constituents account for 0.4% of the ambient OA mass; however, large uncertainties in mass closure remain because of the lack of authentic standards. This study highlights the potential of light-absorbing BrC OA constituents from peat, fern/leaf, and charcoal burning and their importance in the atmosphere.

Effect of Home Bleaching on the Translucency of CAD/CAM Systems.

PubMed

Karci, Muhammet; Demir, Necla

2017-11-10

To evaluate the effect of a home bleaching agent (Opalescence PF) on the translucency of CAD/CAM ceramic systems. The 28 sintered ceramic specimens (IPS Empress CAD and IPS e.max CAD; 15 mm long, 10 mm wide, 1 mm thick) were divided into two subgroups as control and bleaching groups (n = 7). Carbamide peroxide (CP), 16%, home bleaching agent was applied onto the surface of each specimen for 6 hours per day for 7 days. A spectrophotometer (VITA Easyshade Advance) was used to measure the CIE L * a * b * coordinates and the reflectance value (Y) of the specimens on white and black backgrounds. The translucency parameter (TP), contrast ratio (CR), and opalescence parameter (OP) of the specimens were calculated. The data were statistically analyzed using Kolmogorov-Smirnov, one-way ANOVA, Tukey's test, and Pearson's correlation. Statistically significant differences in the TP values after 16% CP bleaching treatment were observed (p ˂ 0.05); however, no significant differences were found in the OP and CR values after the surface treatment (p ˃ 0.05). According to our study, patients who have all-ceramic restorations in their mouths should be careful when using home bleaching agents, because whitening agents can affect the translucency of all-ceramic restorations such as e.max CAD and Empress CAD. © 2017 by the American College of Prosthodontists.

Using the OMI Aerosol Index and Absorption Aerosol Optical Depth to evaluate the NASA MERRA Aerosol Reanalysis

NASA Astrophysics Data System (ADS)

Buchard, V.; da Silva, A. M.; Colarco, P. R.; Darmenov, A.; Randles, C. A.; Govindaraju, R.; Torres, O.; Campbell, J.; Spurr, R.

2014-12-01

A radiative transfer interface has been developed to simulate the UV Aerosol Index (AI) from the NASA Goddard Earth Observing System version 5 (GEOS-5) aerosol assimilated fields. The purpose of this work is to use the AI and Aerosol Absorption Optical Depth (AAOD) derived from the Ozone Monitoring Instrument (OMI) measurements as independent validation for the Modern Era Retrospective analysis for Research and Applications Aerosol Reanalysis (MERRAero). MERRAero is based on a version of the GEOS-5 model that is radiatively coupled to the Goddard Chemistry, Aerosol, Radiation, and Transport (GOCART) aerosol module and includes assimilation of Aerosol Optical Depth (AOD) from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. Since AI is dependent on aerosol concentration, optical properties and altitude of the aerosol layer, we make use of complementary observations to fully diagnose the model, including AOD from the Multi-angle Imaging SpectroRadiometer (MISR), aerosol retrievals from the Aerosol Robotic Network (AERONET) and attenuated backscatter coefficients from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) mission to ascertain potential misplacement of plume height by the model. By sampling dust, biomass burning and pollution events in 2007 we have compared model produced AI and AAOD with the corresponding OMI products, identifying regions where the model representation of absorbing aerosols was deficient. As a result of this study over the Saharan dust region, we have obtained a new set of dust aerosol optical properties that retains consistency with the MODIS AOD data that were assimilated, while resulting in better agreement with aerosol absorption measurements from OMI. The analysis conducted over the South African and South American biomass burning regions indicates that revising the spectrally-dependent aerosol absorption properties in the near-UV region improves the modeled-observed AI comparisons

Using the OMI aerosol index and absorption aerosol optical depth to evaluate the NASA MERRA Aerosol Reanalysis

NASA Astrophysics Data System (ADS)

Buchard, V.; da Silva, A. M.; Colarco, P. R.; Darmenov, A.; Randles, C. A.; Govindaraju, R.; Torres, O.; Campbell, J.; Spurr, R.

2015-05-01

A radiative transfer interface has been developed to simulate the UV aerosol index (AI) from the NASA Goddard Earth Observing System version 5 (GEOS-5) aerosol assimilated fields. The purpose of this work is to use the AI and aerosol absorption optical depth (AAOD) derived from the Ozone Monitoring Instrument (OMI) measurements as independent validation for the Modern Era Retrospective analysis for Research and Applications Aerosol Reanalysis (MERRAero). MERRAero is based on a version of the GEOS-5 model that is radiatively coupled to the Goddard Chemistry, Aerosol, Radiation, and Transport (GOCART) aerosol module and includes assimilation of aerosol optical depth (AOD) from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. Since AI is dependent on aerosol concentration, optical properties and altitude of the aerosol layer, we make use of complementary observations to fully diagnose the model, including AOD from the Multi-angle Imaging SpectroRadiometer (MISR), aerosol retrievals from the AErosol RObotic NETwork (AERONET) and attenuated backscatter coefficients from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) mission to ascertain potential misplacement of plume height by the model. By sampling dust, biomass burning and pollution events in 2007 we have compared model-produced AI and AAOD with the corresponding OMI products, identifying regions where the model representation of absorbing aerosols was deficient. As a result of this study over the Saharan dust region, we have obtained a new set of dust aerosol optical properties that retains consistency with the MODIS AOD data that were assimilated, while resulting in better agreement with aerosol absorption measurements from OMI. The analysis conducted over the southern African and South American biomass burning regions indicates that revising the spectrally dependent aerosol absorption properties in the near-UV region improves the modeled-observed AI comparisons

A step-by-step introduction to rule-based design of synthetic genetic constructs using GenoCAD.

PubMed

Wilson, Mandy L; Hertzberg, Russell; Adam, Laura; Peccoud, Jean

2011-01-01

GenoCAD is an open source web-based system that provides a streamlined, rule-driven process for designing genetic sequences. GenoCAD provides a graphical interface that allows users to design sequences consistent with formalized design strategies specific to a domain, organization, or project. Design strategies include limited sets of user-defined parts and rules indicating how these parts are to be combined in genetic constructs. In addition to reducing design time to minutes, GenoCAD improves the quality and reliability of the finished sequence by ensuring that the designs follow established rules of sequence construction. GenoCAD.org is a publicly available instance of GenoCAD that can be found at www.genocad.org. The source code and latest build are available from SourceForge to allow advanced users to install and customize GenoCAD for their unique needs. This chapter focuses primarily on how the GenoCAD tools can be used to organize genetic parts into customized personal libraries, then how these libraries can be used to design sequences. In addition, GenoCAD's parts management system and search capabilities are described in detail. Instructions are provided for installing a local instance of GenoCAD on a server. Some of the future enhancements of this rapidly evolving suite of applications are briefly described. Copyright © 2011 Elsevier Inc. All rights reserved.

Individualized Human CAD Models: Anthropmetric Morphing and Body Tissue Layering

DTIC Science & Technology

2014-07-31

Part Flow Chart of the Interaction among VBA Macros, Excel® Spreadsheet, and SolidWorks Front View of the Male and Female Soldier CAD Model...yellow highlighting. The spreadsheet is linked to the CAD model by macros created with the Visual Basic for Application ( VBA ) editor in Microsoft Excel...basically three working parts to the anthropometric morphing that are all interconnected ( VBA macros, Excel spreadsheet, and SolidWorks). The flow

Analysis of HOM Problems in the C-ADS Main Linac

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

Huang, Burn; Ng, King Yuen

2017-05-18

Excitation of higher-order modes (HOMs) in superconducting cavities may severely affect the operation of the main linac in the Chinese Accelerator Driven System (CADS). Preliminary analysis is made on the effects of beam dynamic, which includes possible longitudinal and transverse emittance enlargements, as well as the possibility of beam breakup. Suggestions are given for further investigation. Comparison is made between the C-ADS and the Fermilab Project X.

Version control system of CAD documents and PLC projects

NASA Astrophysics Data System (ADS)

Khudyakov, P. Yu; Kisel’nikov, A. Yu; Startcev, I. M.; Kovalev, A. A.

2018-05-01

The paper presents the process of developing a version control system for CAD documents and PLC projects. The software was tested and the optimal composition of the modules was selected. The introduction of the system has made it possible to increase the safety and stability of the process control systems, as well as to reduce the number of conflicts for versions of CAD files. The number of incidents at the enterprise related to the use of incorrect versions of PLC projects is reduced to 0.

Chairside CAD/CAM materials. Part 3: Cyclic fatigue parameters and lifetime predictions.

PubMed

Wendler, Michael; Belli, Renan; Valladares, Diana; Petschelt, Anselm; Lohbauer, Ulrich

2018-06-01

Chemical and mechanical degradation play a key role on the lifetime of dental restorative materials. Therefore, prediction of their long-term performance in the oral environment should base on fatigue, rather than inert strength data, as commonly observed in the dental material's field. The objective of the present study was to provide mechanistic fatigue parameters of current dental CAD/CAM materials under cyclic biaxial flexure and assess their suitability in predicting clinical fracture behaviors. Eight CAD/CAM materials, including polycrystalline zirconia (IPS e.max ZirCAD), reinforced glasses (Vitablocs Mark II, IPS Empress CAD), glass-ceramics (IPS e.max CAD, Suprinity PC, Celtra Duo), as well as hybrid materials (Enamic, Lava Ultimate) were evaluated. Rectangular plates (12×12×1.2mm 3 ) with highly polished surfaces were prepared and tested in biaxial cyclic fatigue in water until fracture using the Ball-on-Three-Balls (B3B) test. Cyclic fatigue parameters n and A* were obtained from the lifetime data for each material and further used to build SPT diagrams. The latter were used to compare in-vitro with in-vivo fracture distributions for IPS e.max CAD and IPS Empress CAD. Susceptibility to subcritical crack growth under cyclic loading was observed for all materials, being more severe (n≤20) in lithium-based glass-ceramics and Vitablocs Mark II. Strength degradations of 40% up to 60% were predicted after only 1 year of service. Threshold stress intensity factors (K th ) representing the onset of subcritical crack growth (SCG), were estimated to lie in the range of 0.37-0.44 of K Ic for the lithium-based glass-ceramics and Vitablocs Mark II and between 0.51-0.59 of K Ic for the other materials. Failure distributions associated with mechanistic estimations of strength degradation in-vitro showed to be useful in interpreting failure behavior in-vivo. The parameter K th stood out as a better predictor of clinical performance in detriment to the SCG n

An automated distinction of DICOM images for lung cancer CAD system

NASA Astrophysics Data System (ADS)

Suzuki, H.; Saita, S.; Kubo, M.; Kawata, Y.; Niki, N.; Nishitani, H.; Ohmatsu, H.; Eguchi, K.; Kaneko, M.; Moriyama, N.

2009-02-01

Automated distinction of medical images is an important preprocessing in Computer-Aided Diagnosis (CAD) systems. The CAD systems have been developed using medical image sets with specific scan conditions and body parts. However, varied examinations are performed in medical sites. The specification of the examination is contained into DICOM textual meta information. Most DICOM textual meta information can be considered reliable, however the body part information cannot always be considered reliable. In this paper, we describe an automated distinction of DICOM images as a preprocessing for lung cancer CAD system. Our approach uses DICOM textual meta information and low cost image processing. Firstly, the textual meta information such as scan conditions of DICOM image is distinguished. Secondly, the DICOM image is set to distinguish the body parts which are identified by image processing. The identification of body parts is based on anatomical structure which is represented by features of three regions, body tissue, bone, and air. The method is effective to the practical use of lung cancer CAD system in medical sites.

The marginal fit of lithium disilicate crowns: Press vs. CAD/CAM.

PubMed

Azar, Basel; Eckert, Steve; Kunkela, Josef; Ingr, Tomaš; Mounajjed, Radek

2018-01-01

This study aimed to compare the vertical marginal gap of teeth restored with lithium disilicate crowns fabricated using CAD/CAM or by pressed ceramic approach. Twenty mandibular third molar teeth were collected after surgical extractions and prepared to receive full veneer crowns. Teeth were optically scanned and lithium disilicate blocks were used to fabricate crowns using CAD/CAM technique. Polyvinyl siloxane impressions of the prepared teeth were made and monolithic pressed lithium disilicate crowns were fabricated. The marginal gap was measured using optical microscope at 200× magnification (Keyence VHX-5000, Japan). Statistical analysis was performed using Wilcoxon test. The lithium disilicate pressed crowns had significantly smaller (p = 0.006) marginal gaps (38 ± 12 μm) than the lithium disilicate CAD/CAM crowns (45 ± 12 μm). This research indicates that lithium disilicate crowns fabricated with the press technique have measurably smaller marginal gaps compared with those fabricated with CAD/CAM technique within in vitro environments. The marginal gaps achieved by the crowns across all groups were within a clinically acceptable range.

Structural Insight into the Core of CAD, the Multifunctional Protein Leading De Novo Pyrimidine Biosynthesis.

PubMed

Moreno-Morcillo, María; Grande-García, Araceli; Ruiz-Ramos, Alba; Del Caño-Ochoa, Francisco; Boskovic, Jasminka; Ramón-Maiques, Santiago

2017-06-06

CAD, the multifunctional protein initiating and controlling de novo biosynthesis of pyrimidines in animals, self-assembles into ∼1.5 MDa hexamers. The structures of the dihydroorotase (DHO) and aspartate transcarbamoylase (ATC) domains of human CAD have been previously determined, but we lack information on how these domains associate and interact with the rest of CAD forming a multienzymatic unit. Here, we prove that a construct covering human DHO and ATC oligomerizes as a dimer of trimers and that this arrangement is conserved in CAD-like from fungi, which holds an inactive DHO-like domain. The crystal structures of the ATC trimer and DHO-like dimer from the fungus Chaetomium thermophilum confirm the similarity with the human CAD homologs. These results demonstrate that, despite being inactive, the fungal DHO-like domain has a conserved structural function. We propose a model that sets the DHO and ATC complex as the central element in the architecture of CAD. Copyright © 2017 Elsevier Ltd. All rights reserved.

Complete Dentures Fabricated with CAD/CAM Technology and a Traditional Clinical Recording Method.

PubMed

Janeva, Nadica; Kovacevska, Gordana; Janev, Edvard

2017-10-15

The introduction of computer-aided design/computer-aided manufacturing (CAD/CAM) technology into complete denture (CD) fabrication ushered in a new era in removable prosthodontics. Commercially available CAD/CAM denture systems are expected to improve upon the disadvantages associated with conventional fabrication. The purpose of this report is to present the workflow involved in fabricating a CD with a traditional clinical recording method and CAD/CAM technology and to summarize the advantages to the dental practitioner and the patient.

rCAD: A Novel Database Schema for the Comparative Analysis of RNA.

PubMed

Ozer, Stuart; Doshi, Kishore J; Xu, Weijia; Gutell, Robin R

2011-12-31

Beyond its direct involvement in protein synthesis with mRNA, tRNA, and rRNA, RNA is now being appreciated for its significance in the overall metabolism and regulation of the cell. Comparative analysis has been very effective in the identification and characterization of RNA molecules, including the accurate prediction of their secondary structure. We are developing an integrative scalable data management and analysis system, the RNA Comparative Analysis Database (rCAD), implemented with SQL Server to support RNA comparative analysis. The platformagnostic database schema of rCAD captures the essential relationships between the different dimensions of information for RNA comparative analysis datasets. The rCAD implementation enables a variety of comparative analysis manipulations with multiple integrated data dimensions for advanced RNA comparative analysis workflows. In this paper, we describe details of the rCAD schema design and illustrate its usefulness with two usage scenarios.

rCAD: A Novel Database Schema for the Comparative Analysis of RNA

PubMed Central

Ozer, Stuart; Doshi, Kishore J.; Xu, Weijia; Gutell, Robin R.

2013-01-01

Beyond its direct involvement in protein synthesis with mRNA, tRNA, and rRNA, RNA is now being appreciated for its significance in the overall metabolism and regulation of the cell. Comparative analysis has been very effective in the identification and characterization of RNA molecules, including the accurate prediction of their secondary structure. We are developing an integrative scalable data management and analysis system, the RNA Comparative Analysis Database (rCAD), implemented with SQL Server to support RNA comparative analysis. The platformagnostic database schema of rCAD captures the essential relationships between the different dimensions of information for RNA comparative analysis datasets. The rCAD implementation enables a variety of comparative analysis manipulations with multiple integrated data dimensions for advanced RNA comparative analysis workflows. In this paper, we describe details of the rCAD schema design and illustrate its usefulness with two usage scenarios. PMID:24772454

TopoCad - A unified system for geospatial data and services

NASA Astrophysics Data System (ADS)

Felus, Y. A.; Sagi, Y.; Regev, R.; Keinan, E.

2013-10-01

"E-government" is a leading trend in public sector activities in recent years. The Survey of Israel set as a vision to provide all of its services and datasets online. The TopoCad system is the latest software tool developed in order to unify a number of services and databases into one on-line and user friendly system. The TopoCad system is based on Web 1.0 technology; hence the customer is only a consumer of data. All data and services are accessible for the surveyors and geo-information professional in an easy and comfortable way. The future lies in Web 2.0 and Web 3.0 technologies through which professionals can upload their own data for quality control and future assimilation with the national database. A key issue in the development of this complex system was to implement a simple and easy (comfortable) user experience (UX). The user interface employs natural language dialog box in order to understand the user requirements. The system then links spatial data with alpha-numeric data in a flawless manner. The operation of the TopoCad requires no user guide or training. It is intuitive and self-taught. The system utilizes semantic engines and machine understanding technologies to link records from diverse databases in a meaningful way. Thus, the next generation of TopoCad will include five main modules: users and projects information, coordinates transformations and calculations services, geospatial data quality control, linking governmental systems and databases, smart forms and applications. The article describes the first stage of the TopoCad system and gives an overview of its future development.

Elevated Glucose Oxidation, Reduced Insulin Secretion, and a Fatty Heart May Be Protective Adaptions in Ischemic CAD.

PubMed

Hannukainen, J C; Lautamäki, R; Mari, A; Pärkkä, J P; Bucci, M; Guzzardi, M A; Kajander, S; Tuokkola, T; Knuuti, J; Iozzo, P

2016-07-01

Insulin resistance, β-cell dysfunction, and ectopic fat deposition have been implicated in the pathogenesis of coronary artery disease (CAD) and type 2 diabetes, which is common in CAD patients. We investigated whether CAD is an independent predictor of these metabolic abnormalities and whether this interaction is influenced by superimposed myocardial ischemia. We studied CAD patients with (n = 8) and without (n = 14) myocardial ischemia and eight non-CAD controls. Insulin sensitivity and secretion and substrate oxidation were measured during fasting and oral glucose tolerance testing. We used magnetic resonance imaging/spectroscopy, positron emission and computerized tomography to characterize CAD, cardiac function, pericardial and abdominal adipose tissue, and myocardial, liver, and pancreatic triglyceride contents. Ischemic CAD was characterized by elevated oxidative glucose metabolism and a proportional decline in β-cell insulin secretion and reduction in lipid oxidation. Cardiac function was preserved in CAD groups, whereas cardiac fat depots were elevated in ischemic CAD compared to non-CAD subjects. Liver and pancreatic fat contents were similar in all groups and related with surrounding adipose masses or systemic insulin sensitivity. In ischemic CAD patients, glucose oxidation is enhanced and correlates inversely with insulin secretion. This can be seen as a mechanism to prevent glucose lowering because glucose is required in oxygen-deprived tissues. On the other hand, the accumulation of cardiac triglycerides may be a physiological adaptation to the limited fatty acid oxidative capacity. Our results underscore the urgent need of clinical trials that define the optimal/safest glycemic range in situations of myocardial ischemia.

Elevated Glucose Oxidation, Reduced Insulin Secretion, and a Fatty Heart May Be Protective Adaptions in Ischemic CAD

PubMed Central

Hannukainen, J. C.; Lautamäki, R.; Mari, A.; Pärkkä, J. P.; Bucci, M.; Guzzardi, M. A.; Kajander, S.; Tuokkola, T.; Knuuti, J.

2016-01-01

Background: Insulin resistance, β-cell dysfunction, and ectopic fat deposition have been implicated in the pathogenesis of coronary artery disease (CAD) and type 2 diabetes, which is common in CAD patients. We investigated whether CAD is an independent predictor of these metabolic abnormalities and whether this interaction is influenced by superimposed myocardial ischemia. Methods and Results: We studied CAD patients with (n = 8) and without (n = 14) myocardial ischemia and eight non-CAD controls. Insulin sensitivity and secretion and substrate oxidation were measured during fasting and oral glucose tolerance testing. We used magnetic resonance imaging/spectroscopy, positron emission and computerized tomography to characterize CAD, cardiac function, pericardial and abdominal adipose tissue, and myocardial, liver, and pancreatic triglyceride contents. Ischemic CAD was characterized by elevated oxidative glucose metabolism and a proportional decline in β-cell insulin secretion and reduction in lipid oxidation. Cardiac function was preserved in CAD groups, whereas cardiac fat depots were elevated in ischemic CAD compared to non-CAD subjects. Liver and pancreatic fat contents were similar in all groups and related with surrounding adipose masses or systemic insulin sensitivity. Conclusions: In ischemic CAD patients, glucose oxidation is enhanced and correlates inversely with insulin secretion. This can be seen as a mechanism to prevent glucose lowering because glucose is required in oxygen-deprived tissues. On the other hand, the accumulation of cardiac triglycerides may be a physiological adaptation to the limited fatty acid oxidative capacity. Our results underscore the urgent need of clinical trials that define the optimal/safest glycemic range in situations of myocardial ischemia. PMID:27045985

Design Automation Using Script Languages. High-Level CAD Templates in Non-Parametric Programs

NASA Astrophysics Data System (ADS)

Moreno, R.; Bazán, A. M.

2017-10-01

The main purpose of this work is to study the advantages offered by the application of traditional techniques of technical drawing in processes for automation of the design, with non-parametric CAD programs, provided with scripting languages. Given that an example drawing can be solved with traditional step-by-step detailed procedures, is possible to do the same with CAD applications and to generalize it later, incorporating references. In today’s modern CAD applications, there are striking absences of solutions for building engineering: oblique projections (military and cavalier), 3D modelling of complex stairs, roofs, furniture, and so on. The use of geometric references (using variables in script languages) and their incorporation into high-level CAD templates allows the automation of processes. Instead of repeatedly creating similar designs or modifying their data, users should be able to use these templates to generate future variations of the same design. This paper presents the automation process of several complex drawing examples based on CAD script files aided with parametric geometry calculation tools. The proposed method allows us to solve complex geometry designs not currently incorporated in the current CAD applications and to subsequently create other new derivatives without user intervention. Automation in the generation of complex designs not only saves time but also increases the quality of the presentations and reduces the possibility of human errors.

Informing Aerosol Transport Models With Satellite Multi-Angle Aerosol Measurements

NASA Technical Reports Server (NTRS)

Limbacher, J.; Patadia, F.; Petrenko, M.; Martin, M. Val; Chin, M.; Gaitley, B.; Garay, M.; Kalashnikova, O.; Nelson, D.; Scollo, S.

2011-01-01

As the aerosol products from the NASA Earth Observing System's Multi-angle Imaging SpectroRadiometer (MISR) mature, we are placing greater focus on ways of using the aerosol amount and type data products, and aerosol plume heights, to constrain aerosol transport models. We have demonstrated the ability to map aerosol air-mass-types regionally, and have identified product upgrades required to apply them globally, including the need for a quality flag indicating the aerosol type information content, that varies depending upon retrieval conditions. We have shown that MISR aerosol type can distinguish smoke from dust, volcanic ash from sulfate and water particles, and can identify qualitative differences in mixtures of smoke, dust, and pollution aerosol components in urban settings. We demonstrated the use of stereo imaging to map smoke, dust, and volcanic effluent plume injection height, and the combination of MISR and MODIS aerosol optical depth maps to constrain wildfire smoke source strength. This talk will briefly highlight where we stand on these application, with emphasis on the steps we are taking toward applying the capabilities toward constraining aerosol transport models, planet-wide.

Aircraft-based Aerosol Size and Composition Measurements during ACE-Asia and CRYSTAL-FACE using an Aerodyne Aerosol Mass Spectrometer

NASA Astrophysics Data System (ADS)

Bahreini, R.; Jimenez, J.; Delia, A.; Flagan, R. C.; Seinfeld, J. H.; Jayne, J. T.; Worsnop, D. R.

2002-12-01

An Aerodyne Aerosol Mass Spectrometer (AMS) was deployed in an aircraft for the first time during the ACE-Asia field campaign. The AMS was operated on board the CIRPAS Twin Otter aircraft to measure the size-resolved chemical composition of the submicron aerosols in the outflow from Eastern Asia. Research flights were carried out from March 31 to May 1, 2001 in an area that covered 127 E-135 E and 32 N-38 N on longitude and latitude, respectively. The submicron aerosol was typically distributed in distinct layers (from the boundary layer to ~ 3700 m). This is consistent with other on-board measurements. The aerosol in the pollution layers was mainly composed of sulfate, ammonium, and organics separated by cleaner layers. Sub-micron nitrate aerosols were also detected in some layers. Since the molar ratio of positive to negative ions did not exceed one on most of the constant altitude legs of the flights, the particles were not completely neutralized. Sulfate and organics concentrations of up to 10 and 5 ug m-3 (STP), respectively, were measured on some pollution layers. AMS measurements of sulfate concentration and NH4/SO4 mass ratio (~0.16 on average) are consistent with previously reported measurements at Cheju Island, South Korea [Charmichael et al., 1997; Chen et al., 1997] and Sapporo, Japan [Kaneyasu et al., 1995]. The mass-weighed size distribution of the sub-micron sulfate was relatively constant from day to day and layer to layer, with an aerodynamic mode at 350-500 nm (vacuum aerodynamic diameter) and FWHM ~ 400 nm on most of the layers. Furthermore, the ratios between SO4/ NH4/ NO3/ Organics were approximately independent of size in the sub-micron size range. Comparisons of AMS data to other on-board aerosol measurements will be presented. In particular, the AMS mass concentration correlates well with the aerosol volume determined by the on-board Differential Automated Classifying Aerosol Detector (DCAD). In addition, preliminary results of airborne size

How to Quickly Import CAD Geometry into Thermal Desktop

NASA Technical Reports Server (NTRS)

Wright, Shonte; Beltran, Emilio

2002-01-01

There are several groups at JPL (Jet Propulsion Laboratory) that are committed to concurrent design efforts, two are featured here. Center for Space Mission Architecture and Design (CSMAD) enables the practical application of advanced process technologies in JPL's mission architecture process. Team I functions as an incubator for projects that are in the Discovery, and even pre-Discovery proposal stages. JPL's concurrent design environment is to a large extent centered on the CAD (Computer Aided Design) file. During concurrent design sessions CAD geometry is ported to other more specialized engineering design packages.

Evaluation of a hydrophilic interaction liquid chromatography design space for sugars and sugar alcohols.

PubMed

Hetrick, Evan M; Kramer, Timothy T; Risley, Donald S

2017-03-17

Based on a column-screening exercise, a column ranking system was developed for sample mixtures containing any combination of 26 sugar and sugar alcohol analytes using 16 polar stationary phases in the HILIC mode with acetonitrile/water or acetone/water mobile phases. Each analyte was evaluated on the HILIC columns with gradient elution and the subsequent chromatography data was compiled into a statistical software package where any subset of the analytes can be selected and the columns are then ranked by the greatest separation. Since these analytes lack chromophores, aerosol-based detectors, including an evaporative light scattering detector (ELSD) and a charged aerosol detector (CAD) were employed for qualitative and quantitative detection. Example qualitative applications are provided to illustrate the practicality and efficiency of this HILIC column ranking. Furthermore, the design-space approach was used as a starting point for a quantitative method for the trace analysis of glucose in trehalose samples in a complex matrix. Knowledge gained from evaluating the design-space led to rapid development of a capable method as demonstrated through validation of the following parameters: specificity, accuracy, precision, linearity, limit of quantitation, limit of detection, and range. Copyright © 2017 Elsevier B.V. All rights reserved.

Fracture and Fatigue Resistance of Cemented versus Fused CAD-on Veneers over Customized Zirconia Implant Abutments.

PubMed

Nossair, Shereen Ahmed; Aboushelib, Moustafa N; Morsi, Tarek Salah

2015-01-05

To evaluate the fracture mechanics of cemented versus fused CAD-on veneers on customized zirconia implant abutments. Forty-five identical customized CAD/CAM zirconia implant abutments (0.5 mm thick) were prepared and seated on short titanium implant abutments (Ti base). A second scan was made to fabricate 45 CAD-on veneers (IPS Empress CAD, A2). Fifteen CAD-on veneers were cemented on the zirconia abutments (Panavia F2.0). Another 15 were fused to the zirconia abutments using low-fusing glass, while manually layered veneers served as control (n = 15). The restorations were subjected to artificial aging (3.2 million cycles between 5 and 10 kg in a water bath at 37°C) before being axially loaded to failure. Fractured specimens were examined using scanning electron microscopy to detect fracture origin, location, and size of critical crack. Stress at failure was calculated using fractography principles (alpha = 0.05). Cemented CAD-on restorations demonstrated significantly higher (F = 72, p < 0.001) fracture load compared to fused CAD-on and manually layered restorations. Fractographic analysis of fractured specimens indicated that cemented CAD-on veneers failed due to radial cracks originating from the veneer/resin interface. Branching of the critical crack was observed in the bulk of the veneer. Fused CAD-on veneers demonstrated cohesive fracture originating at the thickest part of the veneer ceramic, while manually layered veneers failed due to interfacial fracture at the zirconia/veneer interface. Within the limitations of this study, cemented CAD-on veneers on customized zirconia implant abutments demonstrated higher fracture than fused and manually layered veneers. © 2014 by the American College of Prosthodontists.

Flexural resistance of heat-pressed and CAD-CAM lithium disilicate with different translucencies.

PubMed

Fabian Fonzar, Riccardo; Carrabba, Michele; Sedda, Maurizio; Ferrari, Marco; Goracci, Cecilia; Vichi, Alessandro

2017-01-01

To compare flexural strength of CAD-CAM and heat-pressed lithium disilicate. For Pressed specimens (Group A), acrylate polymer blocks were cut with a saw in bars shape. Sprueing, investing and preheating procedures were carried out following manufacturer's instructions. IPS e.max Press ingots (Ivoclar-Vivadent) were divided into subgroups (n=15) according to translucency: A.1=HT-A3; A.2=MT-A3; A.3=LT-A3; A.4=MO2. Ingots were then pressed following manufacturer's instructions. For CAD-CAM specimens (Group B) blocks of IPS e.max CAD (Ivoclar-Vivadent) were divided into subgroups: B.1=HT-A3; B.2=MT-A3; B.3=LT-A3; B.4=MO2. Specimens (n=15) were obtained by cutting the blocks with a saw. Final crystallization was performed following manufacturer's instructions. Both Press and CAD specimens were polished and finished with silica carbide papers of increasing grit. Final dimensions of the specimens were 4.0±0.2mm, 1.2±0.2mm, and 16.0±0.2mm. Specimens were tested using a three-point bending test. Flexural strength, Weibull modulus, and Weibull characteristic strength were calculated. Flexural strength data were statistically analyzed. The overall means of Press and CAD specimens did not differ significantly. Within the Press group different translucencies were found to have similar flexural strength. Within the CAD group, statistically significant differences emerged among the tested translucencies (p<0.001). Specifically, MT had significantly higher flexural strength than HT and MO. Also, LT exhibited significantly higher flexural strength than MO. The choice between IPS e.max Press and IPS e.max CAD formulations can be based on different criteria than flexural resistance. Within each formulation, for IPS e.max Press translucency does not affect the flexural strength while for IPS e.max CAD it is an influential factor. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Biology of the Coarse Aerosol Mode: Insights Into Urban Aerosol Ecology

NASA Astrophysics Data System (ADS)

Dueker, E.; O'Mullan, G. D.; Montero, A.

2015-12-01

Microbial aerosols have been understudied, despite implications for climate studies, public health, and biogeochemical cycling. Because viable bacterial aerosols are often associated with coarse aerosol particles, our limited understanding of the coarse aerosol mode further impedes our ability to develop models of viable bacterial aerosol production, transport, and fate in the outdoor environment, particularly in crowded urban centers. To address this knowledge gap, we studied aerosol particle biology and size distributions in a broad range of urban and rural settings. Our previously published findings suggest a link between microbial viability and local production of coarse aerosols from waterways, waste treatment facilities, and terrestrial systems in urban and rural environments. Both in coastal Maine and in New York Harbor, coarse aerosols and viable bacterial aerosols increased with increasing wind speeds above 4 m s-1, a dynamic that was observed over time scales ranging from minutes to hours. At a New York City superfund-designated waterway regularly contaminated with raw sewage, aeration remediation efforts resulted in significant increases of coarse aerosols and bacterial aerosols above that waterway. Our current research indicates that bacterial communities in aerosols at this superfund site have a greater similarity to bacterial communities in the contaminated waterway with wind speeds above 4 m s-1. Size-fractionated sampling of viable microbial aerosols along the urban waterfront has also revealed significant shifts in bacterial aerosols, and specifically bacteria associated with coarse aerosols, when wind direction changes from onshore to offshore. This research highlights the key connections between bacterial aerosol viability and the coarse aerosol fraction, which is important in assessments of production, transport, and fate of bacterial contamination in the urban environment.

Aerosol Angstrom Absorption Coefficient Comparisons during MILAGRO.

NASA Astrophysics Data System (ADS)

Marley, N. A.; Marchany-Rivera, A.; Kelley, K. L.; Mangu, A.; Gaffney, J. S.

2007-12-01

Measurements of aerosol absorption were obtained as part of the MAX-Mex component of the MILAGRO field campaign at site T0 (Instituto Mexicano de Petroleo in Mexico City) by using a 7-channel aethalometer (Thermo- Anderson) during the month of March, 2006. The absorption measurements obtained in the field at 370, 470, 520, 590, 660, 880, and 950 nm were used to determine the aerosol Angstrom absorption exponents by linear regression. Since, unlike other absorbing aerosol species (e.g. humic like substances, nitrated PAHs), black carbon absorption is relatively constant from the ultraviolet to the infrared with an Angstrom absorption exponent of -1 (1), a comparison of the Angstrom exponents can indicate the presence of aerosol components with an enhanced UV absorption over that expected from BC content alone. The Angstrom exponents determined from the aerosol absorption measurements obtained in the field varied from - 0.7 to - 1.3 during the study and was generally lower in the afternoon than the morning hours, indicating an increase in secondary aerosol formation and photochemically generated UV absorbing species in the afternoon. Twelve-hour integrated samples of fine atmospheric aerosols (<0.1micron) were also collected at site T0 and T1 (Universidad Technologica de Tecamac, State of Mexico) from 5 am to 5 pm (day) and from 5 pm to 5 am (night) during the month of March 2006. Samples were collected on quartz fiber filters with high volume impactor samplers. Continuous absorption spectra of these aerosol samples have been obtained in the laboratory from 280 to 900nm with the use of an integrating sphere coupled to a UV spectrometer (Beckman DU with a Labsphere accessory). The integrating sphere allows the detector to collect and spatially integrate the total radiant flux reflected from the sample and therefore allows for the measurement of absorption on highly reflective or diffusely scattering samples. These continuous spectra have also been used to obtain the

Measurements of Semi-volatile Aerosol and Its Effect on Aerosol Optical Properties During Southern Oxidant and Aerosol Study

NASA Astrophysics Data System (ADS)

Khlystov, A.; Grieshop, A. P.; Saha, P.; Subramanian, R.

2013-12-01

Semi-volatile compounds, including particle-bound water, comprise a large part of aerosol mass and have a significant influence on aerosol lifecycle and its optical properties. Understanding the properties of semi-volatile compounds, especially those pertaining to gas/aerosol partitioning, is of critical importance for our ability to predict concentrations and properties of ambient aerosol. A set of state-of-the-art instruments was deployed at the SEARCH site near Centerville, AL during the Southern Oxidant and Aerosol Study (SOAS) campaign in summer 2013 to measure the effect of temperature and relative humidity on aerosol size distribution, composition and optical properties. Light scattering and absorption by temperature- and humidity-conditioned aerosols was measured using three photo-acoustic extinctiometers (PAX) at three wavelengths (405 nm, 532 nm, and 870 nm). In parallel to these measurements, a long residence time temperature-stepping thermodenuder and a variable residence time constant temperature thermodenuder in combination with three SMPS systems and an Aerosol Chemical Speciation Monitor (ACSM) were used to assess aerosol volatility and kinetics of aerosol evaporation. It was found that both temperature and relative humidity have a strong effect on aerosol optical properties. The variable residence time thermodenuder data suggest that aerosol equilibrated fairly quickly, within 2 s, in contrast to other ambient observations. Preliminary analysis show that approximately 50% and 90% of total aerosol mass evaporated at temperatures of 100 C and 180C, respectively. Evaporation varied substantially with ambient aerosol loading and composition and meteorology. During course of this study, T50 (temperatures at which 50% aerosol mass evaporates) varied from 60 C to more than 120 C.

Pipe Drafting with CAD. Teacher Edition.

ERIC Educational Resources Information Center

Smithson, Buddy

This teacher's guide contains nine units of instruction for a course on computer-assisted pipe drafting. The course covers the following topics: introduction to pipe drafting with CAD (computer-assisted design); flow diagrams; pipe and pipe components; valves; piping plans and elevations; isometrics; equipment fabrication drawings; piping design…

Grinding damage assessment for CAD-CAM restorative materials.

PubMed

Curran, Philippe; Cattani-Lorente, Maria; Anselm Wiskott, H W; Durual, Stéphane; Scherrer, Susanne S

2017-03-01

To assess surface/subsurface damage after grinding with diamond discs on five CAD-CAM restorative materials and to estimate potential losses in strength based on crack size measurements of the generated damage. The materials tested were: Lithium disilicate (LIT) glass-ceramic (e.max CAD), leucite glass-ceramic (LEU) (Empress CAD), feldspar ceramic (VM2) (Vita Mark II), feldspar ceramic-resin infiltrated (EN) (Enamic) and a composite reinforced with nano ceramics (LU) (Lava Ultimate). Specimens were cut from CAD-CAM blocs and pair-wise mirror polished for the bonded interface technique. Top surfaces were ground with diamond discs of respectively 75, 54 and 18μm. Chip damage was measured on the bonded interface using SEM. Fracture mechanics relationships were used to estimate fracture stresses based on average and maximum chip depths assuming these to represent strength limiting flaws subjected to tension and to calculate potential losses in strength compared to manufacturer's data. Grinding with a 75μm diamond disc induced on a bonded interface critical chips averaging 100μm with a potential strength loss estimated between 33% and 54% for all three glass-ceramics (LIT, LEU, VM2). The softer materials EN and LU were little damage susceptible with chips averaging respectively 26μm and 17μm with no loss in strength. Grinding with 18μm diamond discs was still quite detrimental for LIT with average chip sizes of 43μm and a potential strength loss of 42%. It is essential to understand that when grinding glass-ceramics or feldspar ceramics with diamond discs surface and subsurface damage are induced which have the potential of lowering the strength of the ceramic. Careful polishing steps should be carried out after grinding especially when dealing with glass-ceramics. Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Spatial data software integration - Merging CAD/CAM/mapping with GIS and image processing

NASA Technical Reports Server (NTRS)

Logan, Thomas L.; Bryant, Nevin A.

1987-01-01

The integration of CAD/CAM/mapping with image processing using geographic information systems (GISs) as the interface is examined. Particular emphasis is given to the development of software interfaces between JPL's Video Image Communication and Retrieval (VICAR)/Imaged Based Information System (IBIS) raster-based GIS and the CAD/CAM/mapping system. The design and functions of the VICAR and IBIS are described. Vector data capture and editing are studied. Various software programs for interfacing between the VICAR/IBIS and CAD/CAM/mapping are presented and analyzed.

The Effect of Aerosol Hygroscopicity and Volatility on Aerosol Optical Properties During Southern Oxidant and Aerosol Study

NASA Astrophysics Data System (ADS)

Khlystov, A.; Grieshop, A. P.; Saha, P.; Subramanian, R.

2014-12-01

Secondary organic aerosol (SOA) from biogenic sources can influence optical properties of ambient aerosol by altering its hygroscopicity and contributing to light absorption directly via formation of brown carbon and indirectly by enhancing light absorption by black carbon ("lensing effect"). The magnitude of these effects remains highly uncertain. A set of state-of-the-art instruments was deployed at the SEARCH site near Centerville, AL during the Southern Oxidant and Aerosol Study (SOAS) campaign in summer 2013 to measure the effect of relative humidity and temperature on aerosol size distribution, composition and optical properties. Light scattering and absorption by temperature- and humidity-conditioned aerosols was measured using three photo-acoustic extinctiometers (PAX) at three wavelengths (405 nm, 532 nm, and 870 nm). The sample-conditioning system provided measurements at ambient RH, 10%RH ("dry"), 85%RH ("wet"), and 200 C ("TD"). In parallel to these measurements, a long residence time temperature-stepping thermodenuder (TD) and a variable residence time constant temperature TD in combination with three SMPS systems and an Aerosol Chemical Speciation Monitor (ACSM) were used to assess aerosol volatility and kinetics of aerosol evaporation. We will present results of the on-going analysis of the collected data set. We will show that both temperature and relative humidity have a strong effect on aerosol optical properties. SOA appears to increase aerosol light absorption by about 10%. TD measurements suggest that aerosol equilibrated fairly quickly, within 2 s. Evaporation varied substantially with ambient aerosol loading and composition and meteorology.

Stress Perfusion Coronary Flow Reserve Versus Cardiac Magnetic Resonance for Known or Suspected CAD.

PubMed

Kato, Shingo; Saito, Naka; Nakachi, Tatsuya; Fukui, Kazuki; Iwasawa, Tae; Taguri, Masataka; Kosuge, Masami; Kimura, Kazuo

2017-08-15

Phase-contrast (PC) cine magnetic resonance imaging (MRI) of the coronary sinus is a noninvasive method to quantify coronary flow reserve (CFR). This study sought to compare the prognostic value of CFR by cardiac magnetic resonance (CMR) and stress perfusion CMR to predict major adverse cardiac events (MACE). Participants included 276 patients with known coronary artery disease (CAD) and 400 with suspected CAD. CFR was calculated as myocardial blood flow during adenosine triphosphate infusion divided by myocardial blood flow at rest using PC cine MRI of the coronary sinus. During a median follow-up of 2.3 years, 47 patients (7%) experienced MACE. Impaired CFR (<2.0) and >10% ischemia on stress perfusion CMR were significantly associated with MACE in patients with known CAD (hazard ratio [HR]: 5.17 and HR: 5.10, respectively) and suspected CAD (HR: 14.16 and HR: 6.50, respectively). The area under the curve for predicting MACE was 0.773 for CFR and 0.731 for stress perfusion CMR (p = 0.58) for patients with known CAD, and 0.885 for CFR and 0.776 for stress perfusion CMR (p = 0.059) in the group with suspected CAD. In patients with known CAD, sensitivity, specificity, and positive and negative predictive values to predict MACE were 64%, 91%, 38%, and 97%, respectively, for CFR, and 82%, 59%, 15%, and 97%, respectively, for stress perfusion CMR. In the suspected CAD group, these values were 65%, 99%, 80%, and 97%, respectively, for CFR, and 72%, 83%, 22%, and 98%, respectively, for stress perfusion CMR. The predictive values of CFR and stress perfusion CMR for MACE were comparable in patients with known CAD. In patients with suspected CAD, CFR showed higher HRs and areas under the curve than stress perfusion CMR, suggesting that CFR assessment by PC cine MRI might provide better risk stratification for patients with suspected CAD. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Rule-Based Design of Plant Expression Vectors Using GenoCAD.

PubMed

Coll, Anna; Wilson, Mandy L; Gruden, Kristina; Peccoud, Jean

2015-01-01

Plant synthetic biology requires software tools to assist on the design of complex multi-genic expression plasmids. Here a vector design strategy to express genes in plants is formalized and implemented as a grammar in GenoCAD, a Computer-Aided Design software for synthetic biology. It includes a library of plant biological parts organized in structural categories and a set of rules describing how to assemble these parts into large constructs. Rules developed here are organized and divided into three main subsections according to the aim of the final construct: protein localization studies, promoter analysis and protein-protein interaction experiments. The GenoCAD plant grammar guides the user through the design while allowing users to customize vectors according to their needs. Therefore the plant grammar implemented in GenoCAD will help plant biologists take advantage of methods from synthetic biology to design expression vectors supporting their research projects.

Chairside CAD/CAM materials. Part 1: Measurement of elastic constants and microstructural characterization.

PubMed

Belli, Renan; Wendler, Michael; de Ligny, Dominique; Cicconi, Maria Rita; Petschelt, Anselm; Peterlik, Herwig; Lohbauer, Ulrich

2017-01-01

A deeper understanding of the mechanical behavior of dental restorative materials requires an insight into the materials elastic constants and microstructure. Here we aim to use complementary methodologies to thoroughly characterize chairside CAD/CAM materials and discuss the benefits and limitations of different analytical strategies. Eight commercial CAM/CAM materials, ranging from polycrystalline zirconia (e.max ZirCAD, Ivoclar-Vivadent), reinforced glasses (Vitablocs Mark II, VITA; Empress CAD, Ivoclar-Vivadent) and glass-ceramics (e.max CAD, Ivoclar-Vivadent; Suprinity, VITA; Celtra Duo, Dentsply) to hybrid materials (Enamic, VITA; Lava Ultimate, 3M ESPE) have been selected. Elastic constants were evaluated using three methods: Resonant Ultrasound Spectroscopy (RUS), Resonant Beam Technique (RBT) and Ultrasonic Pulse-Echo (PE). The microstructures were characterized using Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), Raman Spectroscopy and X-ray Diffraction (XRD). Young's modulus (E), Shear modulus (G), Bulk modulus (B) and Poisson's ratio (ν) were obtained for each material. E and ν reached values ranging from 10.9 (Lava Ultimate) to 201.4 (e.max ZirCAD) and 0.173 (Empress CAD) to 0.47 (Lava Ultimate), respectively. RUS showed to be the most complex and reliable method, while the PE method the easiest to perform but most unreliable. All dynamic methods have shown limitations in measuring the elastic constants of materials showing high damping behavior (hybrid materials). SEM images, Raman spectra and XRD patterns were made available for each material, showing to be complementary tools in the characterization of their crystal phases. Here different methodologies are compared for the measurement of elastic constants and microstructural characterization of CAD/CAM restorative materials. The elastic properties and crystal phases of eight materials are herein fully characterized. Copyright © 2016 The Academy of Dental Materials

Novel concept for neutron detection: proportional counter filled with 10B nanoparticle aerosol

NASA Astrophysics Data System (ADS)

Amaro, F. D.; Monteiro, C. M. B.; Dos Santos, J. M. F.; Antognini, A.

2017-02-01

The high neutron detection efficiency, good gamma-ray discrimination and non-toxicity of 3He made of proportional counters filled with this gas the obvious choice for neutron detection, particularly in radiation portal monitors (RPM), used to control the illicit transport of nuclear material, of which neutron detectors are key components. 3He is very rare and during the last decade this gas has become increasingly difficult to acquire. With the exception of BF3, which is toxic, no other gas can be used for neutron detection in proportional counters. We present an alternative where the 3He atoms are replaced by nanoparticles made of another neutron sensitive material, 10B. The particles are dispersed in a gaseous volume, forming an aerosol with neutron sensitive properties. A proportional counter filled with such aerosol was exposed to a thermal neutron beam and the recorded response indicates that the neutrons have interacted with the particles in the aerosol. This original technique, which transforms a standard proportional gas mixture into a neutron sensitive aerosol, is a breakthrough in the field of radiation detection and has the potential to become an alternative to the use of 3He in proportional counters.

Constructing An Event Based Aerosol Product Under High Aerosol Loading Conditions

NASA Astrophysics Data System (ADS)

Levy, R. C.; Shi, Y.; Mattoo, S.; Remer, L. A.; Zhang, J.

2016-12-01

High aerosol loading events, such as the Indonesia's forest fire in Fall 2015 or the persistent wintertime haze near Beijing, gain tremendous interests due to their large impact on regional visibility and air quality. Understanding the optical properties of these events and further being able to simulate and predict these events are beneficial. However, it is a great challenge to consistently identify and then retrieve aerosol optical depth (AOD) from passive sensors during heavy aerosol events. Some reasons include:1). large differences between optical properties of high-loading aerosols and those under normal conditions, 2) spectral signals of optically thick aerosols can be mistaken with surface depending on aerosol types, and 3) Extremely optically thick aerosol plumes can also be misidentified as clouds due to its high optical thickness. Thus, even under clear-sky conditions, the global distribution of extreme aerosol events is not well captured in datasets such as the MODIS Dark-Target (DT) aerosol product. In this study, with the synthetic use of OMI Aerosol Index, MODIS cloud product, and operational DT product, the heavy smoke events over the seven sea region are identified and retrieved over the dry season. An event based aerosol product that would compensate the standard "global" aerosol retrieval will be created and evaluated. The impact of missing high AOD retrievals on the regional aerosol climatology will be studied using this newly developed research product.

TARDEC FIXED HEEL POINT (FHP): DRIVER CAD ACCOMMODATION MODEL VERIFICATION REPORT

DTIC Science & Technology

2017-11-09

SUPPLEMENTARY NOTES N/A 14. ABSTRACT Easy-to-use Computer-Aided Design (CAD) tools, known as accommodation models, are needed by the ground vehicle... designers when developing the interior workspace for the occupant. The TARDEC Fixed Heel Point (FHP): Driver CAD Accommodation Model described in this...is intended to provide the composite boundaries representing the body of the defined target design population, including posture prediction

Implant-supported fixed dental prostheses with CAD/CAM-fabricated porcelain crown and zirconia-based framework.

PubMed

Takaba, Masayuki; Tanaka, Shinpei; Ishiura, Yuichi; Baba, Kazuyoshi

2013-07-01

Recently, fixed dental prostheses (FDPs) with a hybrid structure of CAD/CAM porcelain crowns adhered to a CAD/CAM zirconia framework (PAZ) have been developed. The aim of this report was to describe the clinical application of a newly developed implant-supported FDP fabrication system, which uses PAZ, and to evaluate the outcome after a maximum application period of 36 months. Implants were placed in three patients with edentulous areas in either the maxilla or mandible. After the implant fixtures had successfully integrated with bone, gold-platinum alloy or zirconia custom abutments were first fabricated. Zirconia framework wax-up was performed on the custom abutments, and the CAD/CAM zirconia framework was prepared using the CAD/CAM system. Next, wax-up was performed on working models for porcelain crown fabrication, and CAD/CAM porcelain crowns were fabricated. The CAD/CAM zirconia frameworks and CAD/CAM porcelain crowns were bonded using adhesive resin cement, and the PAZ was cemented. Cementation of the implant superstructure improved the esthetics and masticatory efficiency in all patients. No undesirable outcomes, such as superstructure chipping, stomatognathic dysfunction, or periimplant bone resorption, were observed in any of the patients. PAZ may be a potential solution for ceramic-related clinical problems such as chipping and fracture and associated complicated repair procedures in implant-supported FDPs. © 2012 by the American College of Prosthodontists.

Comparison between five CAD/CAM systems for fit of zirconia copings.

PubMed

Habib, Syed Rashid; Al Otaibi, Asim Khaled; Al Anazi, Talal Ali; Al Anazi, Samer Mosleh

2018-01-01

The aim of this in-vitro study was to investigate the marginal and internal fit of zirconia copings fabricated by five CAD/CAM (computer-aided design/computer-assisted manufacture) systems. A typodont mandibular right first molar was prepared according to ideal parameters for a zirconia crown, scanned digitally, and 100 identical resin dies fabricated by 3D printing. Samples were randomly divided into five groups and sent to CAD/CAM systems for zirconia copings (A, Ceramill-Motion 2, Amann Girrbach; B, Weiland, Ivoclar Vivadent; C, Cerec, Ivoclar Vivadent; D, Prettau Zirconia, Zirkonzahn; E, Cad4dent). CAD of the copings included standardized cement space of 30 µm and CAM was carried out. Copings were tried/adjusted on the respective dies and embedded under a standardized load of 20 N in self-curing resin. Samples were sectioned mesiodistally into two halves. Marginal and internal gap values were measured with a digital microscope at 50 to 200 × magnification at nine sites. The lowest and highest mean gap values of 46.93 ± 13.50 and 101.65 ± 35.56 μm were found for Group A and Group D, respectively. ANOVA showed a statistically significant difference between the mean values of all the groups (P = .000). Multiple comparisons with post hoc Tukey test indicated a statistically significant difference (P < .05) between: Group A and all groups except B; B with D; C with A; D with A; and B and E with A. Mean buccal/lingual gap value was found to be 51.54 ± 58.54 μm. Of the nine sites, the least gap resulted at the buccal axial wall and the greatest at the central groove. The overall mean gap recorded for the copings was 72.43 ± 57.56 μm. Marginal and internal adaptations of CAD/CAM zirconia copings is influenced by manufacturing technique, and variations exist for different systems. Measurement sites showed different levels. CAD/CAM systems investigated showed a clinically acceptable level of gap values (< 120 µm).

Improving digital breast tomosynthesis reading time: A pilot multi-reader, multi-case study using concurrent Computer-Aided Detection (CAD).

PubMed

Balleyguier, Corinne; Arfi-Rouche, Julia; Levy, Laurent; Toubiana, Patrick R; Cohen-Scali, Franck; Toledano, Alicia Y; Boyer, Bruno

2017-12-01

Evaluate concurrent Computer-Aided Detection (CAD) with Digital Breast Tomosynthesis (DBT) to determine impact on radiologist performance and reading time. The CAD system detects and extracts suspicious masses, architectural distortions and asymmetries from DBT planes that are blended into corresponding synthetic images to form CAD-enhanced synthetic images. Review of CAD-enhanced images and navigation to corresponding planes to confirm or dismiss potential lesions allows radiologists to more quickly review DBT planes. A retrospective, crossover study with and without CAD was conducted with six radiologists who read an enriched sample of 80 DBT cases including 23 malignant lesions in 21 women. Area Under the Receiver Operating Characteristic (ROC) Curve (AUC) compared the readings with and without CAD to determine the effect of CAD on overall interpretation performance. Sensitivity, specificity, recall rate and reading time were also assessed. Multi-reader, multi-case (MRMC) methods accounting for correlation and requiring correct lesion localization were used to analyze all endpoints. AUCs were based on a 0-100% probability of malignancy (POM) score. Sensitivity and specificity were based on BI-RADS scores, where 3 or higher was positive. Average AUC across readers without CAD was 0.854 (range: 0.785-0.891, 95% confidence interval (CI): 0.769,0.939) and 0.850 (range: 0.746-0.905, 95% CI: 0.751,0.949) with CAD (95% CI for difference: -0.046,0.039), demonstrating non-inferiority of AUC. Average reduction in reading time with CAD was 23.5% (95% CI: 7.0-37.0% improvement), from an average 48.2 (95% CI: 39.1,59.6) seconds without CAD to 39.1 (95% CI: 26.2,54.5) seconds with CAD. Per-patient sensitivity was the same with and without CAD (0.865; 95% CI for difference: -0.070,0.070), and there was a small 0.022 improvement (95% CI for difference: -0.046,0.089) in per-lesion sensitivity from 0.790 without CAD to 0.812 with CAD. A slight reduction in specificity with a -0

Mechanical Drafting with CAD. Teacher Edition.

ERIC Educational Resources Information Center

McClain, Gerald R.

This instructor's manual contains 13 units of instruction for a course on mechanical drafting with options for using computer-aided drafting (CAD). Each unit includes some or all of the following basic components of a unit of instruction: objective sheet, suggested activities for the teacher, assignment sheets and answers to assignment sheets,…

Three-Dimensional Digital Evaluation of the Fit of Endocrowns Fabricated from Different CAD/CAM Materials.

PubMed

Zimmermann, Moritz; Valcanaia, Andre; Neiva, Gisele; Mehl, Albert; Fasbinder, Dennis

2018-03-06

A wide variety of CAD/CAM materials are available for single-tooth restorations. CAD/CAM material characteristics are different and may influence CAM fabrication accuracy. There is no study investigating the influence of different CAD/CAM materials on the final fit of the restoration. The aim of this study was to evaluate the fit of endocrowns fabricated from different CAD/CAM materials using a new 3D evaluation method with an intraoral scanning system. The null hypothesis was that there are no significant differences for the fitting accuracy of different CAD/CAM materials. Preparation for an endocrown was performed on a maxillary right first molar on a typodont, and restorations were fabricated with a chairside CAD/CAM system (CEREC Omnicam, MCXL). Three groups using three different CAD/CAM materials were established (each n = 10): zirconia-reinforced lithium silicate ceramic (Celtra Duo; CD), leucite-reinforced silicate ceramic (Empress CAD; EM), resin nanoceramic (Lava Ultimate; LU). A 3D digital measurement technique (OraCheck, Cyfex AG) using an intraoral scanner (CEREC Omnicam) was used to measure the difference in fit between the three materials for a master endocrown preparation. The preparation scan and the endocrown fit scan were matched with special difference analysis software OraCheck. Three areas were selected for fitting accuracy measurements: margin (MA), axial (AX), occlusal (OC). Statistical analysis was performed using 80% percentile, one-way ANOVA, and post-hoc Scheffé test. Significance level was set to p = 0.05. Results varied from best 88.9 ± 7.7 μm for marginal fit of resin nanoceramic restorations (LU_MA) to worst 182.3 ± 24.0 μm for occlusal fit of zirconia-reinforced lithium silicate restorations (CD_OC). Statistically significant differences were found both within and among the test groups. Group CD performed statistically significantly different from group LU for marginal fit (MA) and axial fit (AX) (p < 0.05). For occlusal fit (OC

Analysis on the workspace of palletizing robot based on AutoCAD

NASA Astrophysics Data System (ADS)

Li, Jin-quan; Zhang, Rui; Guan, Qi; Cui, Fang; Chen, Kuan

2017-10-01

In this paper, a four-degree-of-freedom articulated palletizing robot is used as the object of research. Based on the analysis of the overall configuration of the robot, the kinematic mathematical model is established by D-H method to figure out the workspace of the robot. In order to meet the needs of design and analysis, using AutoCAD secondary development technology and AutoLisp language to develop AutoCAD-based 2D and 3D workspace simulation interface program of palletizing robot. At last, using AutoCAD plugin, the influence of structural parameters on the shape and position of the working space is analyzed when the structure parameters of the robot are changed separately. This study laid the foundation for the design, control and planning of palletizing robots.

Imaging aerosol viscosity

NASA Astrophysics Data System (ADS)

Pope, Francis; Athanasiadis, Thanos; Botchway, Stan; Davdison, Nicholas; Fitzgerald, Clare; Gallimore, Peter; Hosny, Neveen; Kalberer, Markus; Kuimova, Marina; Vysniauskas, Aurimas; Ward, Andy

2017-04-01

Organic aerosol particles play major roles in atmospheric chemistry, climate, and public health. Aerosol particle viscosity is important since it can determine the ability of chemical species such as oxidants, organics or water to diffuse into the particle bulk. Recent measurements indicate that OA may be present in highly viscous states; however, diffusion rates of small molecules such as water appear not to be limited by these high viscosities. We have developed a technique for measuring viscosity that allows for the imaging of aerosol viscosity in micron sized aerosols through use of fluorescence lifetime imaging of viscosity sensitive dyes which are also known as 'molecular rotors'. These rotors can be introduced into laboratory generated aerosol by adding minute quantities of the rotor to aerosol precursor prior to aerosolization. Real world aerosols can also be studied by doping them in situ with the rotors. The doping is achieved through generation of ultrafine aerosol particles that contain the rotors; the ultrafine aerosol particles deliver the rotors to the aerosol of interest via impaction and coagulation. This work has been conducted both on aerosols deposited on microscope coverslips and on particles that are levitated in their true aerosol phase through the use of a bespoke optical trap developed at the Central Laser Facility. The technique allows for the direct observation of kinetic barriers caused by high viscosity and low diffusivity in aerosol particles. The technique is non-destructive thereby allowing for multiple experiments to be carried out on the same sample. It can dynamically quantify and track viscosity changes during atmospherically relevant processes such oxidation and hygroscopic growth (1). This presentation will focus on the oxidation of aerosol particles composed of unsaturated and saturated organic species. It will discuss how the type of oxidant, oxidation rate and the composition of the oxidized products affect the time

Manipulating cinnamyl alcohol dehydrogenase (CAD) expression in flax affects fibre composition and properties

PubMed Central

2014-01-01

Background In recent decades cultivation of flax and its application have dramatically decreased. One of the reasons for this is unpredictable quality and properties of flax fibre, because they depend on environmental factors, retting duration and growing conditions. These factors have contribution to the fibre composition, which consists of cellulose, hemicelluloses, lignin and pectin. By far, it is largely established that in flax, lignin reduces an accessibility of enzymes either to pectin, hemicelluloses or cellulose (during retting or in biofuel synthesis and paper production). Therefore, in this study we evaluated composition and properties of flax fibre from plants with silenced CAD (cinnamyl alcohol dehydrogenase) gene, which is key in the lignin biosynthesis. There is evidence that CAD is a useful tool to improve lignin digestibility and/or to lower the lignin levels in plants. Results Two studied lines responded differentially to the introduced modification due to the efficiency of the CAD silencing. Phylogenetic analysis revealed that flax CAD belongs to the “bona-fide” CAD family. CAD down-regulation had an effect in the reduced lignin amount in the flax fibre cell wall and as FT-IR results suggests, disturbed lignin composition and structure. Moreover introduced modification activated a compensatory mechanism which was manifested in the accumulation of cellulose and/or pectin. These changes had putative correlation with observed improved fiber’s tensile strength. Moreover, CAD down-regulation did not disturb at all or has only slight effect on flax plants’ development in vivo, however, the resistance against flax major pathogen Fusarium oxysporum decreased slightly. The modification positively affected fibre possessing; it resulted in more uniform retting. Conclusion The major finding of our paper is that the modification targeted directly to block lignin synthesis caused not only reduced lignin level in fibre, but also affected amount and

On the Use of CAD-Native Predicates and Geometry in Surface Meshing

NASA Technical Reports Server (NTRS)

Aftosmis, M. J.

1999-01-01

Several paradigms for accessing CAD geometry during surface meshing for CFD are discussed. File translation, inconsistent geometry engines and non-native point construction are all identified as sources of non-robustness. The paper argues in favor of accessing CAD parts and assemblies in their native format, without translation, and for the use of CAD-native predicates and constructors in surface mesh generation. The discussion also emphasizes the importance of examining the computational requirements for exact evaluation of triangulation predicates during surface meshing. The native approach is demonstrated through an algorithm for the generation of closed manifold surface triangulations from CAD geometry. CAD parts and assemblies are used in their native format, and a part's native geometry engine is accessed through a modeler-independent application programming interface (API). In seeking a robust and fully automated procedure, the algorithm is based on a new physical space manifold triangulation technique specially developed to avoid robustness issues associated with poorly conditioned mappings. In addition, this approach avoids the usual ambiguities associated with floating-point predicate evaluation on constructed coordinate geometry in a mapped space. The technique is incremental, so that each new site improves the triangulation by some well defined quality measure. The algorithm terminates after achieving a prespecified measure of mesh quality and produces a triangulation such that no angle is less than a given angle bound, a or greater than pi - 2alpha. This result also sets bounds on the maximum vertex degree, triangle aspect-ratio and maximum stretching rate for the triangulation. In addition to the output triangulations for a variety of CAD parts, the discussion presents related theoretical results which assert the existence of such an angle bound, and demonstrate that maximum bounds of between 25 deg and 30 deg may be achieved in practice.

Color change of CAD-CAM materials and composite resin cements after thermocycling.

PubMed

Gürdal, Isil; Atay, Ayse; Eichberger, Marlis; Cal, Ebru; Üsümez, Aslihan; Stawarczyk, Bogna

2018-04-24

The color of resin cements and computer-aided-design and computer-aided-manufacturing (CAD-CAM) restorations may change with aging. The purpose of this in vitro study was to analyze the influence of thermocycling on the color of CAD-CAM materials with underlying resin cement. Seven different CAD-CAM materials, composite resins and glass-ceramics were cut into 0.7-mm and 1.2-mm thicknesses (n=10) and cemented with a dual-polymerizing resin cement, a light-polymerizing resin cement, and a preheated composite resin (N=420). Color values were measured by using spectrophotometry. Specimens were subjected to thermocycling (5°C and 55°C; 5000 cycles). The measured color difference (ΔE) data were analyzed by using descriptive statistics. Normality of data distribution was tested by using the Kolmogorov-Smirnov test. Three-way and 1-way ANOVA followed by the Scheffé post-hoc test and unpaired 2-sample Student t test were computed to determine the significant differences among the tested parameters (α=.05). ΔE values were significantly influenced by the CAD-CAM material (η p 2 =0.85, P<.001) and the resin composite cement (η P 2 =0.03, P=.003) but were not influenced by thickness (P=.179). Significant interactions were present among thickness, cement, and CAD-CAM materials (P<.001). Vita Suprinity and GC Cerasmart showed significantly the lowest ΔE values (P<.001). The highest ΔE values were observed for IPS Empress CAD. The dual-polymerizing resin cement showed significantly lower ΔE values than the preheated composite resin (P=.003). Restoration materials and composite resin cement types used for cementation influence the amount of color change due to aging. Copyright © 2018 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Identifying Aerosol Type/Mixture from Aerosol Absorption Properties Using AERONET

NASA Technical Reports Server (NTRS)

Giles, D. M.; Holben, B. N.; Eck, T. F.; Sinyuk, A.; Dickerson, R. R.; Thompson, A. M.; Slutsker, I.; Li, Z.; Tripathi, S. N.; Singh, R. P.;

Study on the integration approaches to CAD/CAPP/FMS in garment CIMS

NASA Astrophysics Data System (ADS)

Wang, Xiankui; Tian, Wensheng; Liu, Chengying; Li, Zhizhong

1995-08-01

Computer integrated manufacturing system (CIMS), as an advanced methodology, has been applied in many industry fields. There is, however, little research on the application of CIMS in the garment industry, especially on the integrated approach to CAD, CAPP, and FMS in garment CIMS. In this paper, the current situations of CAD, CAPP, and FMS in the garment industry are discussed, and information requirements between them as well as the integrated approaches are also investigated. The representation of the garments' product data by the group technology coding is proposed. Based on the group technology, a shared data base as an integration element can be constructed, which leads to the integration of CAD/CAPP/FMS in garment CIMS.

Potential effect of CAD systems on the detection of actionable nodules in chest CT scans during routine reporting

NASA Astrophysics Data System (ADS)

Wormanns, Dag; Beyer, Florian; Butzbach, Arnauld; Zierott, Livia; Heindel, Walter

2006-03-01

The purpose of the presented study was to determine the impact of two different CAD systems used as concur-rent reader for detection of actionable nodules (>4 mm) on the interpretation of chest CT scans during routine reporting. Fifty consecutive MDCT scans (1 mm or 1.25 mm slice thickness, 0.8 mm reconstruction increment) were se-lected from clinical routine. All cases were read by a resident and a staff radiologist, and a written report was available in the radiology information system (RIS). The RIS report mentioned at least one actionable pulmonary nodule in 18 cases (50%) and did not report any pulmonary nodule in the remaining 32 cases. Two different recent CAD systems were independently applied to the 50 CT scans as concurrent reader with two radiologists: Siemens LungCare NEV and MEDIAN CAD-Lung. Two radiologists independently reviewed the CAD results and determined if a CAD result was a true positive or a false positive finding. Patients were classified into two groups: in group A if at least one actionable nodule was detected and in group B if no actionable nodules were found. The effect of CAD on routine reporting was simulated as set union of the findings of routine reporting and CAD thus applying CAD as concurrent reader. According to the RIS report group A (patients with at least one actionable nodule) contained 18 cases (36% of all 50 cases), and group B contained 32 cases. Application of a CAD system as concurrent reader resulted in detec-tion of additional CT scans with actionable nodules and reclassification into group A in 16 resp. 18 cases (radi-ologist 1 resp. radiologist 2) with Siemens NEV and in 19 resp. 18 cases with MEDIAN CAD-Lung. In seven cases MEDIAN CAD-Lung and in four cases Siemens NEV reclassified a case into group A while the other CAD system missed the relevant finding. Sensitivity on a nodule (>4 mm) base was .45 for Siemens NEV and .55 for MEDIAN CAD-Lung; the difference was not yet significant (p=.077). In our study use of CAD

Variation in CAD Secondary Prevention Prescription among Outpatient Cardiology Practices: Insights from the NCDR®

PubMed Central

Maddox, Thomas M.; Chan, Paul S.; Spertus, John A.; Tang, Fengming; Jones, Phil; Ho, P. Michael; Bradley, Steven M.; Tsai, Thomas T.; Bhatt, Deepak L.; Peterson, Pamela N.

2014-01-01

Objectives This study assesses practice variation of secondary prevention medication prescription among coronary artery disease (CAD) patients treated in outpatient practices participating in the NCDR® PINNACLE Registry®. Background Among patients with CAD, secondary prevention with a combination of beta-blockers, angiotensin converting enzyme inhibitors/angiotensin receptor blockers, and statins reduces cardiac mortality and myocardial infarction (MI). Accordingly, every CAD patient should receive the combination of these medications for which they are eligible. However, little is known about current prescription patterns of these medications and the variation in use among outpatient cardiology clinics. Methods Using data from NCDR® PINNACLE Registry®, a national outpatient cardiology practice registry, we assessed medication prescription patterns among eligible CAD patients between July 2008 and December 2010. Overall rates of prescription and variation by practice were calculated, adjusting for patient characteristics. Results Among 156,145 CAD patients in 58 practices, 103,830 (66.5%) were prescribed the optimal combination of medications for which they were eligible. The median rate of optimal combined prescription by practice was 73.5% and varied from 28.8% to 100%. After adjustment for patient factors, the practice median rate ratio for prescription was 1.25 (95% CI 1.2,1.32), indicating a 25% likelihood that 2 random practices would differ in treating identical CAD patients. Conclusions Among a national registry of CAD patients treated in outpatient cardiology practices, over one-third of patients failed to receive their optimal combination of secondary prevention medications. Significant variation was observed across practices, even after adjusting for patient characteristics, suggesting that quality improvement efforts may be needed to support more uniform practice. PMID:24184238

Experimental CAD Course Uses Low-Cost Systems.

ERIC Educational Resources Information Center

Wohlers, Terry

1984-01-01

Describes the outstanding results obtained when a department of industrial sciences used special software on microcomputers to teach computer-aided design (CAD) as an alternative to much more expensive equipment. The systems used and prospects for the future are also considered. (JN)

Assessment of reliability of CAD-CAM tooth-colored implant custom abutments.

PubMed

Guilherme, Nuno Marques; Chung, Kwok-Hung; Flinn, Brian D; Zheng, Cheng; Raigrodski, Ariel J

2016-08-01

Information is lacking about the fatigue resistance of computer-aided design and computer-aided manufacturing (CAD-CAM) tooth-colored implant custom abutment materials. The purpose of this in vitro study was to investigate the reliability of different types of CAD-CAM tooth-colored implant custom abutments. Zirconia (Lava Plus), lithium disilicate (IPS e.max CAD), and resin-based composite (Lava Ultimate) abutments were fabricated using CAD-CAM technology and bonded to machined titanium-6 aluminum-4 vanadium (Ti-6Al-4V) alloy inserts for conical connection implants (NobelReplace Conical Connection RP 4.3×10 mm; Nobel Biocare). Three groups (n=19) were assessed: group ZR, CAD-CAM zirconia/Ti-6Al-4V bonded abutments; group RC, CAD-CAM resin-based composite/Ti-6Al-4V bonded abutments; and group LD, CAD-CAM lithium disilicate/Ti-6Al-4V bonded abutments. Fifty-seven implant abutments were secured to implants and embedded in autopolymerizing acrylic resin according to ISO standard 14801. Static failure load (n=5) and fatigue failure load (n=14) were tested. Weibull cumulative damage analysis was used to calculate step-stress reliability at 150-N and 200-N loads with 2-sided 90% confidence limits. Representative fractured specimens were examined using stereomicroscopy and scanning electron microscopy to observe fracture patterns. Weibull plots revealed β values of 2.59 for group ZR, 0.30 for group RC, and 0.58 for group LD, indicating a wear-out or cumulative fatigue pattern for group ZR and load as the failure accelerating factor for groups RC and LD. Fractographic observation disclosed that failures initiated in the interproximal area where the lingual tensile stresses meet the compressive facial stresses for the early failure specimens. Plastic deformation of titanium inserts with fracture was observed for zirconia abutments in fatigue resistance testing. Significantly higher reliability was found in group ZR, and no significant differences in reliability were

Computer Aided Detection (CAD) Systems for Mammography and the Use of GRID in Medicine

NASA Astrophysics Data System (ADS)

Lauria, Adele

It is well known that the most effective way to defeat breast cancer is early detection, as surgery and medical therapies are more efficient when the disease is diagnosed at an early stage. The principal diagnostic technique for breast cancer detection is X-ray mammography. Screening programs have been introduced in many European countries to invite women to have periodic radiological breast examinations. In such screenings, radiologists are often required to examine large numbers of mammograms with a double reading, that is, two radiologists examine the images independently and then compare their results. In this way an increment in sensitivity (the rate of correctly identified images with a lesion) of up to 15% is obtained.1,2 In most radiological centres, it is a rarity to find two radiologists to examine each report. In recent years different Computer Aided Detection (CAD) systems have been developed as a support to radiologists working in mammography: one may hope that the "second opinion" provided by CAD might represent a lower cost alternative to improve the diagnosis. At present, four CAD systems have obtained the FDA approval in the USA. † Studies3,4 show an increment in sensitivity when CAD systems are used. Freer and Ulissey in 2001 5 demonstrated that the use of a commercial CAD system (ImageChecker M1000, R2 Technology) increases the number of cancers detected up to 19.5% with little increment in recall rate. Ciatto et al.,5 in a study simulating a double reading with a commercial CAD system (SecondLook‡), showed a moderate increment in sensitivity while reducing specificity (the rate of correctly identified images without a lesion). Notwithstanding these optimistic results, there is an ongoing debate to define the advantages of the use of CAD as second reader: the main limits underlined, e.g., by Nishikawa6 are that retrospective studies are considered much too optimistic and that clinical studies must be performed to demonstrate a statistically

Aerosol mobility size spectrometer

DOEpatents

Wang, Jian; Kulkarni, Pramod

2007-11-20

A device for measuring aerosol size distribution within a sample containing aerosol particles. The device generally includes a spectrometer housing defining an interior chamber and a camera for recording aerosol size streams exiting the chamber. The housing includes an inlet for introducing a flow medium into the chamber in a flow direction, an aerosol injection port adjacent the inlet for introducing a charged aerosol sample into the chamber, a separation section for applying an electric field to the aerosol sample across the flow direction and an outlet opposite the inlet. In the separation section, the aerosol sample becomes entrained in the flow medium and the aerosol particles within the aerosol sample are separated by size into a plurality of aerosol flow streams under the influence of the electric field. The camera is disposed adjacent the housing outlet for optically detecting a relative position of at least one aerosol flow stream exiting the outlet and for optically detecting the number of aerosol particles within the at least one aerosol flow stream.

Advancements in CAD/CAM technology: Options for practical implementation.

PubMed

Alghazzawi, Tariq F

2016-04-01

The purpose of this review is to present a comprehensive review of the current published literature investigating the various methods and techniques for scanning, designing, and fabrication of CAD/CAM generated restorations along with detailing the new classifications of CAD/CAM technology. I performed a review of a PubMed using the following search terms "CAD/CAM, 3D printing, scanner, digital impression, and zirconia". The articles were screened for further relevant investigations. The search was limited to articles written in English, published from 2001 to 2015. In addition, a manual search was also conducted through articles and reference lists retrieved from the electronic search and peer-reviewed journals. CAD/CAM technology has advantages including digital impressions and models, and use of virtual articulators. However, the implementation of this technology is still considered expensive and requires highly trained personnel. Currently, the design software has more applications including complete dentures and removable partial denture frameworks. The accuracy of restoration fabrication can be best attained with 5 axes milling units. The 3D printing technology has been incorporated into dentistry, but does not include ceramics and is limited to polymers. In the future, optical impressions will be replaced with ultrasound impressions using ultrasonic waves, which have the capability to penetrate the gingiva non-invasively without retraction cords and not be affected by fluids. The coming trend for most practitioners will be the use of an acquisition camera attached to a computer with the appropriate software and the capability of forwarding the image to the laboratory. Copyright © 2016 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

ANRIL rs2383207 polymorphism and coronary artery disease (CAD) risk: a meta-analysis with observational studies.

PubMed

Wang, P; Dong, P; Yang, X

2016-10-31

Some studies investigated the association of antisense non-coding RNA in the INK4 locus (ANRIL) rs2383207 polymorphism with coronary artery disease (CAD) risk. However, the result was still inconsistent. The aim of this study was to investigate whether there is an association between the ANRIL rs2383207 polymorphism and CAD risk. We carried out a PubMed (Medline), EMBASE database search covering all published articles. The strength of association between ANRIL rs2383207 polymorphism and CAD risk was assessed by calculating OR with 95% CI. A total of 13 case-control studies involving 6796 cases and 9956 controls were included in this meta-analysis. ANRIL rs2383207polymorphism was associated with a significantly an increased risk of CAD (OR=1.47; 95%CI, 1.33-1.62). We also found that this polymorphism increased CAD risk in Caucasians (OR=1.51; 95%CI, 1.28-1.77) and Asians (OR=1.42; 95%CI, 1.26-1.61). In the subgroup analysis according to gender, both women and men were significantly associated with the increased risk of CAD (OR=1.36; 95%CI, 1.03-1.79 and OR=1.58; 95%CI, 1.20-2.09). In the subgroup analysis by age, ANRIL rs2383207 polymorphism showed significant results in old CAD patients and young CAD patients (OR=1.32; 95%CI, 1.20-1.44 and OR=1.53; 95%CI, 1.32-1.77). Furthermore, this polymorphism also influenced myocardial infarction risk (OR=1.75; 95%CI, 1.24-2.47). Even the studies with adjustment for age, gender, smoking were included, the significant association was also observed (OR=1.43; 95%CI, 1.26-1.62). In conclusion, this meta-analysis suggested that ANRIL rs2383207 polymorphism is associated with CAD risk.

Tropospheric Aerosols

NASA Astrophysics Data System (ADS)

Buseck, P. R.; Schwartz, S. E.

2003-12-01

It is widely believed that "On a clear day you can see forever," as proclaimed in the 1965 Broadway musical of the same name. While an admittedly beautiful thought, we all know that this concept is only figurative. Aside from Earth's curvature and Rayleigh scattering by air molecules, aerosols - colloidal suspensions of solid or liquid particles in a gas - limit our vision. Even on the clearest day, there are billions of aerosol particles per cubic meter of air.Atmospheric aerosols are commonly referred to as smoke, dust, haze, and smog, terms that are loosely reflective of their origin and composition. Aerosol particles have arisen naturally for eons from sea spray, volcanic emissions, wind entrainment of mineral dust, wildfires, and gas-to-particle conversion of hydrocarbons from plants and dimethylsulfide from the oceans. However, over the industrial period, the natural background aerosol has been greatly augmented by anthropogenic contributions, i.e., those produced by human activities. One manifestation of this impact is reduced visibility (Figure 1). Thus, perhaps more than in other realms of geochemistry, when considering the composition of the troposphere one must consider the effects of these activities. The atmosphere has become a reservoir for vast quantities of anthropogenic emissions that exert important perturbations on it and on the planetary ecosystem in general. Consequently, much recent research focuses on the effects of human activities on the atmosphere and, through them, on the environment and Earth's climate. For these reasons consideration of the geochemistry of the atmosphere, and of atmospheric aerosols in particular, must include the effects of human activities. (201K)Figure 1. Impairment of visibility by aerosols. Photographs at Yosemite National Park, California, USA. (a) Low aerosol concentration (particulate matter of aerodynamic diameter less than 2.5 μm, PM2.5=0.3 μg m-3; particulate matter of aerodynamic diameter less than 10 �

Black carbon aerosol mixing state, organic aerosols and aerosol optical properties over the UK

NASA Astrophysics Data System (ADS)

McMeeking, G. R.; Morgan, W. T.; Flynn, M.; Highwood, E. J.; Turnbull, K.; Haywood, J.; Coe, H.

2011-05-01

Black carbon (BC) aerosols absorb sunlight thereby leading to a positive radiative forcing and a warming of climate and can also impact human health through their impact on the respiratory system. The state of mixing of BC with other aerosol species, particularly the degree of internal/external mixing, has been highlighted as a major uncertainty in assessing its radiative forcing and hence its climate impact, but few in situ observations of mixing state exist. We present airborne single particle soot photometer (SP2) measurements of refractory BC (rBC) mass concentrations and mixing state coupled with aerosol composition and optical properties measured in urban plumes and regional pollution over the UK. All data were obtained using instrumentation flown on the UK's BAe-146-301 large Atmospheric Research Aircraft (ARA) operated by the Facility for Airborne Atmospheric Measurements (FAAM). We measured sub-micron aerosol composition using an aerosol mass spectrometer (AMS) and used positive matrix factorization to separate hydrocarbon-like (HOA) and oxygenated organic aerosols (OOA). We found a higher number fraction of thickly coated rBC particles in air masses with large OOA relative to HOA, higher ozone-to-nitrogen oxides (NOx) ratios and large concentrations of total sub-micron aerosol mass relative to rBC mass concentrations. The more ozone- and OOA-rich air masses were associated with transport from continental Europe, while plumes from UK cities had higher HOA and NOx and fewer thickly coated rBC particles. We did not observe any significant change in the rBC mass absorption efficiency calculated from rBC mass and light absorption coefficients measured by a particle soot absorption photometer despite observing significant changes in aerosol composition and rBC mixing state. The contributions of light scattering and absorption to total extinction (quantified by the single scattering albedo; SSA) did change for different air masses, with lower SSA observed in

Higher macrophage superoxide anion production in coronary artery disease (CAD) patients with Type D personality.

PubMed

Zuccarella-Hackl, Claudia; von Känel, Roland; Thomas, Livia; Kuebler, Peggy; Schmid, Jean-Paul; Mattle, Heinrich P; Mono, Marie-Louise; Rieben, Robert; Wiest, Roland; Wirtz, Petra H

2016-06-01

Type D personality (Type D) is an independent psychosocial risk factor for poor cardiac prognosis and increased mortality in patients with cardiovascular disease (CVD), but the involved mechanisms are poorly understood. Macrophages play a pivotal role in atherosclerosis, the process underlying coronary artery disease (CAD). We investigated macrophage superoxide anion production in production in CAD patients with and without Type D. We studied 20 male CAD patients with Type D (M:66.7±9.9years) and 20 age-matched male CAD patients without Type D (M:67.7±8.5years). Type D was measured using the DS14 questionnaire with the two subscales 'negative affectivity' and 'social inhibition'. We assessed macrophage superoxide anion production using the WST-1 assay. All analyses were controlled for potential confounders. CAD patients with Type D showed higher superoxide anion production compared to CAD patients without Type D (F(1,38)=15.57, p<0.001). Complementary analyses using the Type D subscales 'negative affectivity' and 'social inhibition', and their interaction as continuous measures, showed that both Type D subscales (negative affectivity: (ß=0.48, p=0.002, R(2)=0.227); social inhibition: (ß=0.46, p=0.003, R(2)=0.208)) and their interaction (ß=0.36, p=0.022, R(2)=0.130) were associated with higher WST-1 reduction scores. Results remained significant when controlling for classical CVD risk factors (i.e. body mass index, mean arterial blood pressure), atherosclerosis severity (i.e. intima media thickness, presence of carotid plaques), and psychological factors (depressive symptom severity, chronic stress). Our results indicate higher macrophage superoxide anion production in CAD patients with Type D compared to those without Type D. This may suggest a mechanism contributing to increased morbidity and mortality in CAD patients with Type D. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Association between Androgenic Hormone Levels and the Risk of Developing Coronary Artery Disease (CAD).

PubMed

Allameh, Farzad; Pourmand, Gholamreza; Bozorgi, Ali; Nekuie, Sepideh; Namdari, Farshad

2016-01-01

The aim of the study was to evaluate the relationship between the serum levels of androgens and Coronary Artery Disease (CAD) in an Iranian population. Male individuals admitted to Tehran Heart Center and Sina Hospital, Tehran, Iran from 2011-2012 were categorized into CAD and control groups based on selective coronary angiography. Baseline demographic data, including age, BMI, diabetes, and a history of hypertension were recorded. Patients were also assessed for their serum levels of total testosterone, free testosterone, estradiol, dehydroepi and rosterone sulfate (DHEA-S), and Sex Hormone Binding Globulin (SHBG). Data analysis was carried out chi-square and ANOVA tests as well as logistic regression analysis. Two hundred patients were in the CAD group and 135 individuals in control group. In the CAD group, 69 had single-vessel disease, 49 had two-vessel diseases, and 82 had three-vessel diseases. Statistically significant differences were observed between the individuals in the two groups with respect to age (P<0.0001), diabetes (P<0.0001), and a history of hypertension (P=0.018). The serum levels of free testosterone (P=0.048) and DHEA-S (P<0.0001) were significantly higher in the control group than in the CAD group; however, the serum level of SHBG was higher in the CAD group than in the control group (P=0.007). Results of the logistic regression analysis indicated that only age (P=0.042) and diabetes (P=0.003) had significant relationships with CAD. Although the serum levels of some of the androgens were significantly different between the two groups, no association was found between androgenic hormone levels and the risk of CAD, due mainly to the effect of age and diabetes.

Reliability and validity of the AutoCAD software method in lumbar lordosis measurement

PubMed Central

Letafatkar, Amir; Amirsasan, Ramin; Abdolvahabi, Zahra; Hadadnezhad, Malihe

2011-01-01

Objective The aim of this study was to determine the reliability and validity of the AutoCAD software method in lumbar lordosis measurement. Methods Fifty healthy volunteers with a mean age of 23 ± 1.80 years were enrolled. A lumbar lateral radiograph was taken on all participants, and the lordosis was measured according to the Cobb method. Afterward, the lumbar lordosis degree was measured via AutoCAD software and flexible ruler methods. The current study is accomplished in 2 parts: intratester and intertester evaluations of reliability as well as the validity of the flexible ruler and software methods. Results Based on the intraclass correlation coefficient, AutoCAD's reliability and validity in measuring lumbar lordosis were 0.984 and 0.962, respectively. Conclusions AutoCAD showed to be a reliable and valid method to measure lordosis. It is suggested that this method may replace those that are costly and involve health risks, such as radiography, in evaluating lumbar lordosis. PMID:22654681

Reliability and validity of the AutoCAD software method in lumbar lordosis measurement.

PubMed

Letafatkar, Amir; Amirsasan, Ramin; Abdolvahabi, Zahra; Hadadnezhad, Malihe

2011-12-01

The aim of this study was to determine the reliability and validity of the AutoCAD software method in lumbar lordosis measurement. Fifty healthy volunteers with a mean age of 23 ± 1.80 years were enrolled. A lumbar lateral radiograph was taken on all participants, and the lordosis was measured according to the Cobb method. Afterward, the lumbar lordosis degree was measured via AutoCAD software and flexible ruler methods. The current study is accomplished in 2 parts: intratester and intertester evaluations of reliability as well as the validity of the flexible ruler and software methods. Based on the intraclass correlation coefficient, AutoCAD's reliability and validity in measuring lumbar lordosis were 0.984 and 0.962, respectively. AutoCAD showed to be a reliable and valid method to measure lordosis. It is suggested that this method may replace those that are costly and involve health risks, such as radiography, in evaluating lumbar lordosis.

From Artisanal to CAD-CAM Blocks: State of the Art of Indirect Composites.

PubMed

Mainjot, A K; Dupont, N M; Oudkerk, J C; Dewael, T Y; Sadoun, M J

2016-05-01

Indirect composites have been undergoing an impressive evolution over the last few years. Specifically, recent developments in computer-aided design-computer-aided manufacturing (CAD-CAM) blocks have been associated with new polymerization modes, innovative microstructures, and different compositions. All these recent breakthroughs have introduced important gaps among the properties of the different materials. This critical state-of-the-art review analyzes the strengths and weaknesses of the different varieties of CAD-CAM composite materials, especially as compared with direct and artisanal indirect composites. Indeed, new polymerization modes used for CAD-CAM blocks-especially high temperature (HT) and, most of all, high temperature-high pressure (HT-HP)-are shown to significantly increase the degree of conversion in comparison with light-cured composites. Industrial processes also allow for the augmentation of the filler content and for the realization of more homogeneous structures with fewer flaws. In addition, due to their increased degree of conversion and their different monomer composition, some CAD-CAM blocks are more advantageous in terms of toxicity and monomer release. Finally, materials with a polymer-infiltrated ceramic network (PICN) microstructure exhibit higher flexural strength and a more favorable elasticity modulus than materials with a dispersed filler microstructure. Consequently, some high-performance composite CAD-CAM blocks-particularly experimental PICNs-can now rival glass-ceramics, such as lithium-disilicate glass-ceramics, for use as bonded partial restorations and crowns on natural teeth and implants. Being able to be manufactured in very low thicknesses, they offer the possibility of developing innovative minimally invasive treatment strategies, such as "no prep" treatment of worn dentition. Current issues are related to the study of bonding and wear properties of the different varieties of CAD-CAM composites. There is also a crucial

[National disease management guidelines (NVL) for chronic CAD : What is new, what is particularly important?].

PubMed

Werdan, K

2016-09-01

Coronary heart disease (CAD) is widespread and affects 1 in 10 of the population in the age group 40-79 years in Germany. The German national management guidelines on chronic CAD comprise evidence and expert-based recommendations for the diagnostics of chronic stable CAD as well as for interdisciplinary/multidisciplinary therapy and care of patients with stable CAD. The focus is on the diagnostics, prevention, medication therapy, revascularization, rehabilitation, general practitioner care and coordination of care. Recommendations for optimizing cooperation between all medical specialties involved as well as the definition of mandatory and appropriate measures are essential aims of the guidelines both to improve the quality of care and to strengthen the position of the patient.

Identification of the CAD gene from Eucalyptus urophylla GLU4 and its functional analysis in transgenic tobacco.

PubMed

Chen, B W; Xiao, Y F; Li, J J; Liu, H L; Qin, Z H; Gai, Y; Jiang, X N

2016-12-02

Cinnamyl alcohol dehydrogenase (CAD) catalyzes the final step in lignin biosynthesis. The genus Eucalyptus belongs to the family Myrtaceae, which is the main cultivated species in China. Eucalyptus urophylla GLU4 (GLU4) is widely grown in Guangxi. It is preferred for pulping because of its excellent cellulose content and fiber length. Based on GLU4 and CAD gene expression, a Eucalyptus variety low in lignin content should be obtained using transgenic technology, which could reduce the cost of pulp and improve the pulping rate, and have favorable prospects for application. However, the role and function of CAD in GLU4 is still unclear. In the present study, EuCAD was cloned from GLU4 and identified using bioinformatic tools. Subsequently, in order to evaluate its impact on lignin synthesis, a full-length EuCAD RNAi vector was constructed, and transgenic tobacco was obtained via Agrobacterium-mediated transformation. A significant decrease in CAD expression and lignin content in transgenic tobacco demonstrated a key role for EuCAD in lignin biosynthesis and established a regulatory role for RNAi. In our study, the direct molecular basis of EuCAD expression was determined, and the potential regulatory effects of this RNAi vector on lignin biosynthesis in E. urophylla GLU4 were demonstrated. Our results provide a theoretical basis for the study of lignin biosynthesis in Eucalyptus.

Aerosol Lidar and MODIS Satellite Comparisons for Future Aerosol Loading Forecast

NASA Technical Reports Server (NTRS)

DeYoung, Russell; Szykman, James; Severance, Kurt; Chu, D. Allen; Rosen, Rebecca; Al-Saadi, Jassim

2006-01-01

Knowledge of the concentration and distribution of atmospheric aerosols using both airborne lidar and satellite instruments is a field of active research. An aircraft based aerosol lidar has been used to study the distribution of atmospheric aerosols in the California Central Valley and eastern US coast. Concurrently, satellite aerosol retrievals, from the MODIS (Moderate Resolution Imaging Spectroradiometer) instrument aboard the Terra and Aqua satellites, were take over the Central Valley. The MODIS Level 2 aerosol data product provides retrieved ambient aerosol optical properties (e.g., optical depth (AOD) and size distribution) globally over ocean and land at a spatial resolution of 10 km. The Central Valley topography was overlaid with MODIS AOD (5x5 sq km resolution) and the aerosol scattering vertical profiles from a lidar flight. Backward air parcel trajectories for the lidar data show that air from the Pacific and northern part of the Central Valley converge confining the aerosols to the lower valley region and below the mixed layer. Below an altitude of 1 km, the lidar aerosol and MODIS AOD exhibit good agreement. Both data sets indicate a high presence of aerosols near Bakersfield and the Tehachapi Mountains. These and other results to be presented indicate that the majority of the aerosols are below the mixed layer such that the MODIS AOD should correspond well with surface measurements. Lidar measurements will help interpret satellite AOD retrievals so that one day they can be used on a routine basis for prediction of boundary layer aerosol pollution events.

TinkerCell: modular CAD tool for synthetic biology.

PubMed

Chandran, Deepak; Bergmann, Frank T; Sauro, Herbert M

2009-10-29

Synthetic biology brings together concepts and techniques from engineering and biology. In this field, computer-aided design (CAD) is necessary in order to bridge the gap between computational modeling and biological data. Using a CAD application, it would be possible to construct models using available biological "parts" and directly generate the DNA sequence that represents the model, thus increasing the efficiency of design and construction of synthetic networks. An application named TinkerCell has been developed in order to serve as a CAD tool for synthetic biology. TinkerCell is a visual modeling tool that supports a hierarchy of biological parts. Each part in this hierarchy consists of a set of attributes that define the part, such as sequence or rate constants. Models that are constructed using these parts can be analyzed using various third-party C and Python programs that are hosted by TinkerCell via an extensive C and Python application programming interface (API). TinkerCell supports the notion of a module, which are networks with interfaces. Such modules can be connected to each other, forming larger modular networks. TinkerCell is a free and open-source project under the Berkeley Software Distribution license. Downloads, documentation, and tutorials are available at http://www.tinkercell.com. An ideal CAD application for engineering biological systems would provide features such as: building and simulating networks, analyzing robustness of networks, and searching databases for components that meet the design criteria. At the current state of synthetic biology, there are no established methods for measuring robustness or identifying components that fit a design. The same is true for databases of biological parts. TinkerCell's flexible modeling framework allows it to cope with changes in the field. Such changes may involve the way parts are characterized or the way synthetic networks are modeled and analyzed computationally. TinkerCell can readily accept

TinkerCell: modular CAD tool for synthetic biology

PubMed Central

Chandran, Deepak; Bergmann, Frank T; Sauro, Herbert M

2009-01-01

Background Synthetic biology brings together concepts and techniques from engineering and biology. In this field, computer-aided design (CAD) is necessary in order to bridge the gap between computational modeling and biological data. Using a CAD application, it would be possible to construct models using available biological "parts" and directly generate the DNA sequence that represents the model, thus increasing the efficiency of design and construction of synthetic networks. Results An application named TinkerCell has been developed in order to serve as a CAD tool for synthetic biology. TinkerCell is a visual modeling tool that supports a hierarchy of biological parts. Each part in this hierarchy consists of a set of attributes that define the part, such as sequence or rate constants. Models that are constructed using these parts can be analyzed using various third-party C and Python programs that are hosted by TinkerCell via an extensive C and Python application programming interface (API). TinkerCell supports the notion of a module, which are networks with interfaces. Such modules can be connected to each other, forming larger modular networks. TinkerCell is a free and open-source project under the Berkeley Software Distribution license. Downloads, documentation, and tutorials are available at . Conclusion An ideal CAD application for engineering biological systems would provide features such as: building and simulating networks, analyzing robustness of networks, and searching databases for components that meet the design criteria. At the current state of synthetic biology, there are no established methods for measuring robustness or identifying components that fit a design. The same is true for databases of biological parts. TinkerCell's flexible modeling framework allows it to cope with changes in the field. Such changes may involve the way parts are characterized or the way synthetic networks are modeled and analyzed computationally. TinkerCell can readily

Is computer aided detection (CAD) cost effective in screening mammography? A model based on the CADET II study

PubMed Central

2011-01-01

Background Single reading with computer aided detection (CAD) is an alternative to double reading for detecting cancer in screening mammograms. The aim of this study is to investigate whether the use of a single reader with CAD is more cost-effective than double reading. Methods Based on data from the CADET II study, the cost-effectiveness of single reading with CAD versus double reading was measured in terms of cost per cancer detected. Cost (Pound (£), year 2007/08) of single reading with CAD versus double reading was estimated assuming a health and social service perspective and a 7 year time horizon. As the equipment cost varies according to the unit size a separate analysis was conducted for high, average and low volume screening units. One-way sensitivity analyses were performed by varying the reading time, equipment and assessment cost, recall rate and reader qualification. Results CAD is cost increasing for all sizes of screening unit. The introduction of CAD is cost-increasing compared to double reading because the cost of CAD equipment, staff training and the higher assessment cost associated with CAD are greater than the saving in reading costs. The introduction of single reading with CAD, in place of double reading, would produce an additional cost of £227 and £253 per 1,000 women screened in high and average volume units respectively. In low volume screening units, the high cost of purchasing the equipment will results in an additional cost of £590 per 1,000 women screened. One-way sensitivity analysis showed that the factors having the greatest effect on the cost-effectiveness of CAD with single reading compared with double reading were the reading time and the reader's professional qualification (radiologist versus advanced practitioner). Conclusions Without improvements in CAD effectiveness (e.g. a decrease in the recall rate) CAD is unlikely to be a cost effective alternative to double reading for mammography screening in UK. This study

The MAC aerosol climatology

NASA Astrophysics Data System (ADS)

Kinne, S.

2015-12-01

Aerosol is highly diverse in space and time. And many different aerosol optical properties are needed (consistent to each other) for the determination of radiative effects. To sidestep a complex (and uncertain) aerosol treatment (emission to mass to optics) a monthly gridded climatology for aerosol properties has been developed. This MPI Aerosol Climatology (MAC) is strongly tied to observational statistics for aerosol column optical properties by AERONET (over land) and by MAN (over oceans). To fill spatial gaps, to address decadal change and to address vertical variability, these sparsely distributed local data are extended with central data of an ensemble of output from global models with complex aerosol modules. This data merging in performed for aerosol column amount (AOD), for aerosol size (AOD,fine) and for aerosol absorption (AAOD). The resulting MAC aerosol climatology is an example for the combination of high quality local observations with spatial, temporal and vertical context from model simulations.

Incidence of undetected cement on CAD/CAM monolithic zirconia crowns and customized CAD/CAM implant abutments. A prospective case series.

PubMed

Wasiluk, Grzegorz; Chomik, Ewa; Gehrke, Peter; Pietruska, Małgorzata; Skurska, Anna; Pietruski, Jan

2017-07-01

The aim of this study was to assess the frequency of cement residues after cementation of CAD/CAM monolithic zirconia crowns on customized CAD/CAM titanium abutments. Sixty premolars and molars were restored on Astra Tech Osseospeed TX ™ implants using single monolithic zirconia crowns fixed on two types of custom-made abutments: Atlantis ™ titanium or Atlantis ™ Gold Hue. Occlusal openings providing access to the abutment screws were designed for retrievability of the crown/abutment connection. After fixation with glass ionomer cement, the crown/abutment units were unscrewed to evaluate the presence of residual cement. Dichotomous assessment of the presence or absence of cement at the crown/abutment unit and peri-implant tissues was performed. Clinically undetected cement excess was visible on 44 of 60 restorations (73.3%). There was no interdependency between residual cement presence and implant location or diameter. However, a dependency between the presence of residual cement and the aspect of the abutment/crown connection could be noted. The majority of the residues were observed on the distal (17.9%) and mesial (15%) aspects. While on the palatal/lingual aspect, the cement was visible in 8.8%; only 3.4% of all surfaces displayed cement residues. Within the limitations of the study, it can be concluded that the use of customized CAD/CAM abutments do not guarantee avoidance of subgingival cement residues after crown cementation. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Remote Sensing of Aerosol and Non-Aerosol Absorption

NASA Technical Reports Server (NTRS)

Kaufman, Y. J.; Dubovik, O.; Holben, B. N.; Remer, L. A.; Tanre, D.; Lau, William K. M. (Technical Monitor)

2001-01-01

Remote sensing of aerosol from the new satellite instruments (e.g. MODIS from Terra) and ground based radiometers (e.g. the AERONET) provides the opportunity to measure the absorption characteristics of the ambient undisturbed aerosol in the entire atmospheric column. For example Landsat and AERONET data are used to measure spectral absorption of sunlight by dust from West Africa. Both Application of the Landsat and AERONET data demonstrate that Saharan dust absorption of solar radiation is several times smaller than the current international standards. This is due to difficulties of measuring dust absorption in situ, and due to the often contamination of dust properties by the presence of air pollution or smoke. We use the remotely sensed aerosol absorption properties described by the spectral sin le scattering albedo, together with statistics of the monthly optical thickness for the fine and coarse aerosol derived from the MODIS data. The result is an estimate of the flux of solar radiation absorbed by the aerosol layer in different regions around the globe where aerosol is prevalent. If this aerosol forcing through absorption is not included in global circulation models, it may be interpreted as anomalous absorption in these regions. In a preliminary exercise we also use the absorption measurements by AERONET, to derive the non-aerosol absorption of the atmosphere in cloud free conditions. The results are obtained for the atmospheric windows: 0.44 microns, 0.66 microns, 0.86 microns and 1.05 microns. In all the locations over the land and ocean that were tested no anomalous absorption in these wavelengths, was found within absorption optical thickness of +/- 0.005.

The efficacy of using computer-aided detection (CAD) for detection of breast cancer in mammography screening: a systematic review.

PubMed

Henriksen, Emilie L; Carlsen, Jonathan F; Vejborg, Ilse Mm; Nielsen, Michael B; Lauridsen, Carsten A

2018-01-01

Background Early detection of breast cancer (BC) is crucial in lowering the mortality. Purpose To present an overview of studies concerning computer-aided detection (CAD) in screening mammography for early detection of BC and compare diagnostic accuracy and recall rates (RR) of single reading (SR) with SR + CAD and double reading (DR) with SR + CAD. Material and Methods PRISMA guidelines were used as a review protocol. Articles on clinical trials concerning CAD for detection of BC in a screening population were included. The literature search resulted in 1522 records. A total of 1491 records were excluded by abstract and 18 were excluded by full text reading. A total of 13 articles were included. Results All but two studies from the SR vs. SR + CAD group showed an increased sensitivity and/or cancer detection rate (CDR) when adding CAD. The DR vs. SR + CAD group showed no significant differences in sensitivity and CDR. Adding CAD to SR increased the RR and decreased the specificity in all but one study. For the DR vs. SR + CAD group only one study reported a significant difference in RR. Conclusion All but two studies showed an increase in RR, sensitivity and CDR when adding CAD to SR. Compared to DR no statistically significant differences in sensitivity or CDR were reported. Additional studies based on organized population-based screening programs, with longer follow-up time, high-volume readers, and digital mammography are needed to evaluate the efficacy of CAD.

Pou5f1-dependent EGF expression controls E-cad endocytosis, cell adhesion, and zebrafish epiboly movements

PubMed Central

Song, Sungmin; Eckerle, Stephanie; Onichtchouk, Daria; Marrs, James A.; Nitschke, Roland; Driever, Wolfgang

2013-01-01

Summary Initiation of motile cell behavior in embryonic development occurs during late blastula stages when gastrulation begins. At this stage, the strong adhesion of blastomeres has to be modulated to enable dynamic behavior, similar to epithelial-to-mesenchymal transitions. We show that in zebrafish MZspg embryos mutant for the stem cell transcription factor Pou5f1/Oct4, which are severely delayed in the epiboly gastrulation movement, all blastomeres are defective in E-cad endosomal trafficking and E-cad accumulates at the plasma membrane. We find that Pou5f1-dependent control of EGF expression regulates endosomal E-cad trafficking. EGFR may act via modulation of p120 activity. Loss of E-cad dynamics reduces cohesion of cells in reaggregation assays. Quantitative analysis of cell behavior indicates that dynamic E-cad endosomal trafficking is required for epiboly cell movements. We hypothesize that dynamic control of E-cad trafficking is essential to effectively generate new adhesion sites when cells move relative to each other. PMID:23484854

Productivity increase through implementation of CAD/CAE workstation

NASA Technical Reports Server (NTRS)

Bromley, L. K.

1985-01-01

The tracking and communication division computer aided design/computer aided engineering system is now operational. The system is utilized in an effort to automate certain tasks that were previously performed manually. These tasks include detailed test configuration diagrams of systems under certification test in the ESTL, floorplan layouts of future planned laboratory reconfigurations, and other graphical documentation of division activities. The significant time savings achieved with this CAD/CAE system are examined: (1) input of drawings and diagrams; (2) editing of initial drawings; (3) accessibility of the data; and (4) added versatility. It is shown that the Applicon CAD/CAE system, with its ease of input and editing, the accessibility of data, and its added versatility, has made more efficient many of the necessary but often time-consuming tasks associated with engineering design and testing.

Impact of aerosol size representation on modeling aerosol-cloud interactions

DOE PAGES

Zhang, Y.; Easter, R. C.; Ghan, S. J.; ...

2002-11-07

In this study, we use a 1-D version of a climate-aerosol-chemistry model with both modal and sectional aerosol size representations to evaluate the impact of aerosol size representation on modeling aerosol-cloud interactions in shallow stratiform clouds observed during the 2nd Aerosol Characterization Experiment. Both the modal (with prognostic aerosol number and mass or prognostic aerosol number, surface area and mass, referred to as the Modal-NM and Modal-NSM) and the sectional approaches (with 12 and 36 sections) predict total number and mass for interstitial and activated particles that are generally within several percent of references from a high resolution 108-section approach.more » The modal approach with prognostic aerosol mass but diagnostic number (referred to as the Modal-M) cannot accurately predict the total particle number and surface areas, with deviations from the references ranging from 7-161%. The particle size distributions are sensitive to size representations, with normalized absolute differences of up to 12% and 37% for the 36- and 12-section approaches, and 30%, 39%, and 179% for the Modal-NSM, Modal-NM, and Modal-M, respectively. For the Modal-NSM and Modal-NM, differences from the references are primarily due to the inherent assumptions and limitations of the modal approach. In particular, they cannot resolve the abrupt size transition between the interstitial and activated aerosol fractions. For the 12- and 36-section approaches, differences are largely due to limitations of the parameterized activation for non-log-normal size distributions, plus the coarse resolution for the 12-section case. Differences are larger both with higher aerosol (i.e., less complete activation) and higher SO2 concentrations (i.e., greater modification of the initial aerosol distribution).« less

Some Workplace Effects of CAD and CAM.

ERIC Educational Resources Information Center

Ebel, Karl-H.; Ulrich, Erhard

1987-01-01

Examines the impact of computer-aided design (CAD) and computer-aided manufacturing (CAM) on employment, work organization, working conditions, job content, training, and industrial relations in several countries. Finds little evidence of negative employment effects since productivity gains are offset by various compensatory factors. (Author/CH)

Fabricating CAD/CAM Implant-Retained Mandibular Bar Overdentures: A Clinical and Technical Overview.

PubMed

Goo, Chui Ling; Tan, Keson Beng Choon

2017-01-01

This report describes the clinical and technical aspects in the oral rehabilitation of an edentulous patient with knife-edge ridge at the mandibular anterior edentulous region, using implant-retained overdentures. The application of computer-aided design and computer-aided manufacturing (CAD/CAM) in the fabrication of the overdenture framework simplifies the laboratory process of the implant prostheses. The Nobel Procera CAD/CAM System was utilised to produce a lightweight titanium overdenture bar with locator attachments. It is proposed that the digital workflow of CAD/CAM milled implant overdenture bar allows us to avoid numerous technical steps and possibility of casting errors involved in the conventional casting of such bars.

3D-CAD Effects on Creative Design Performance of Different Spatial Abilities Students

ERIC Educational Resources Information Center

Chang, Y.

2014-01-01

Students' creativity is an important focus globally and is interrelated with students' spatial abilities. Additionally, three-dimensional computer-assisted drawing (3D-CAD) overcomes barriers to spatial expression during the creative design process. Does 3D-CAD affect students' creative abilities? The purpose of this study was to explore the…

Ovulation leads women to perceive sexy cads as good dads.

PubMed

Durante, Kristina M; Griskevicius, Vladas; Simpson, Jeffry A; Cantú, Stephanie M; Li, Norman P

2012-08-01

Why do some women pursue relationships with men who are attractive, dominant, and charming but who do not want to be in relationships--the prototypical sexy cad? Previous research shows that women have an increased desire for such men when they are ovulating, but it is unclear why ovulating women would think it is wise to pursue men who may be unfaithful and could desert them. Using both college-age and community-based samples, in 3 studies we show that ovulating women perceive charismatic and physically attractive men, but not reliable and nice men, as more committed partners and more devoted future fathers. Ovulating women perceive that sexy cads would be good fathers to their own children but not to the children of other women. This ovulatory-induced perceptual shift is driven by women who experienced early onset of puberty. Taken together, the current research identifies a novel proximate reason why ovulating women pursue relationships with sexy cads, complementing existing research that identifies the ultimate, evolutionary reasons for this behavior.

Shear Bond Strength of Repair Systems to New CAD/CAM Restorative Materials.

PubMed

Üstün, Özlem; Büyükhatipoğlu, Işıl Keçik; Seçilmiş, Aslı

2016-11-23

To evaluate the bond strength of repair systems (Ceramic Repair, Clearfil Repair) to computer-aided design/computer-assisted machining (CAD/CAM) restorative materials (IPS e.max CAD, Vita Suprinity, Vita Enamic, Lava Ultimate). Thermally aged CAD/CAM restorative material specimens (5000 cycles between 5°C and 55°C) were randomly divided into two groups according to the repair system: Ceramic Repair (37% phosphoric acid + Monobond-S + Heliobond + Tetric N Ceram) or Clearfil Repair (40% phosphoric acid + mixture of Clearfil Porcelain Bond Activator and Clearfil SE Bond Primer + Clearfil SE Bond + Filtek Z250). The resin composite was light-cured on conditioned specimens. All specimens were stored in distilled water at 37°C for 24 hours and then additionally aged for 5000 thermal cycles. The shear bond strength test was performed using a universal testing machine (0.5 mm/min). Two-way ANOVA was used to detect significance differences according to the CAD/CAM material and composite repair system factors. Subgroup analyses were conducted using the least significant difference post-hoc test. The results of two-way ANOVA indicated that bond strength values varied according to the restorative materials (p < 0.05). No significant differences were observed between the CAD/CAM restorative materials (p > 0.05), except in the Vita Suprinity group (p < 0.05). Moreover, no differences were observed between the repair systems. Both the Clearfil and Ceramic repair systems used in the study allow for successful repairs. © 2016 by the American College of Prosthodontists.

The Sentinel-4 detectors: architecture and performance

NASA Astrophysics Data System (ADS)

Skegg, Michael P.; Hermsen, Markus; Hohn, Rüdiger; Williges, Christian; Woffinden, Charles; Levillain, Yves; Reulke, Ralf

2017-09-01

The Sentinel-4 instrument is an imaging spectrometer, developed by Airbus under ESA contract in the frame of the joint European Union (EU)/ESA COPERNICUS program. SENTINEL-4 will provide accurate measurements of trace gases from geostationary orbit, including key atmospheric constituents such as ozone, nitrogen dioxide, sulfur dioxide, formaldehyde, as well as aerosol and cloud properties. Key to achieving these atmospheric measurements are the two CCD detectors, covering the wavelengths in the ranges 305 nm to 500 nm (UVVIS) and 750 to 775 nm (NIR) respectively. The paper describes the architecture, and operation of these two CCD detectors, which have an unusually high full-well capacity and a very specific architecture and read-out sequence to match the requirements of the Sentinel- 4 instrument. The key performance aspects and their verification through measurement are presented, with a focus on an unusual, bi-modal dark signal generation rate observed during test.

The influence of polishing techniques on pre-polymerized CAD\\CAM acrylic resin denture bases

PubMed Central

Alammari, Manal Rahma

2017-01-01

Background Lately, computer-aided design and computer-aided manufacturing (CAD/CAM) has broadly been successfully employed in dentistry. The CAD/CAM systems have recently become commercially available for fabrication of complete dentures, and are considered as an alternative technique to conventionally processed acrylic resin bases. However, they have not yet been fully investigated. Objective The purpose of this study was to inspect the effects of mechanical polishing and chemical polishing on the surface roughness (Ra) and contact angle (wettability) of heat-cured, auto-cured and CAD/CAM denture base acrylic resins. Methods This study was conducted at the Advanced Dental Research Laboratory Center of King Abdulaziz University from March to June 2017. Three denture base materials were selected: heat cure poly-methylmethacrylate resin, thermoplastic (polyamide resin) and (CAD\\CAM) denture base resin. Sixty specimens were prepared and divided into three groups, twenty in each. Each group was divided according to the polishing techniques into (Mech P) and (Chem P), ten specimens in each; surface roughness and wettability were investigated. Data were analyzed by SPSS version 22, using one-way ANOVA and Pearson coefficient. Results One-way analysis of variance (ANOVA) and post hoc tests were used for comparing the surface roughness values between three groups which revealed a statistical significant difference between them (p1<0.001). Heat-cured denture base material of (Group I) in both methods, showed the highest mean surface roughness value (2.44±0.07, 2.72±0.09, Mech P and Chem P respectively); while CAD\\CAM denture base material (group III) showed the least mean values (1.08±0.23, 1.39±0.31, Mech P and Chem P respectively). CAD/CAM showed the least contact angle in both polishing methods, which were statistically significant at 5% level (p=0.034 and p<0.001). Conclusion Mechanical polishing produced lower surface roughness of CAD\\CAM denture base resin with

The influence of polishing techniques on pre-polymerized CAD\\CAM acrylic resin denture bases.

PubMed

Alammari, Manal Rahma

2017-10-01

Lately, computer-aided design and computer-aided manufacturing (CAD/CAM) has broadly been successfully employed in dentistry. The CAD/CAM systems have recently become commercially available for fabrication of complete dentures, and are considered as an alternative technique to conventionally processed acrylic resin bases. However, they have not yet been fully investigated. The purpose of this study was to inspect the effects of mechanical polishing and chemical polishing on the surface roughness (Ra) and contact angle (wettability) of heat-cured, auto-cured and CAD/CAM denture base acrylic resins. This study was conducted at the Advanced Dental Research Laboratory Center of King Abdulaziz University from March to June 2017. Three denture base materials were selected: heat cure poly-methylmethacrylate resin, thermoplastic (polyamide resin) and (CAD\\CAM) denture base resin. Sixty specimens were prepared and divided into three groups, twenty in each. Each group was divided according to the polishing techniques into (Mech P) and (Chem P), ten specimens in each; surface roughness and wettability were investigated. Data were analyzed by SPSS version 22, using one-way ANOVA and Pearson coefficient. One-way analysis of variance (ANOVA) and post hoc tests were used for comparing the surface roughness values between three groups which revealed a statistical significant difference between them (p 1 <0.001). Heat-cured denture base material of (Group I) in both methods, showed the highest mean surface roughness value (2.44±0.07, 2.72±0.09, Mech P and Chem P respectively); while CAD\\CAM denture base material (group III) showed the least mean values (1.08±0.23, 1.39±0.31, Mech P and Chem P respectively). CAD/CAM showed the least contact angle in both polishing methods, which were statistically significant at 5% level (p=0.034 and p<0.001). Mechanical polishing produced lower surface roughness of CAD\\CAM denture base resin with superior smooth surface compared to chemical

Comparison of denture base adaptation between CAD-CAM and conventional fabrication techniques.

PubMed

Goodacre, Brian J; Goodacre, Charles J; Baba, Nadim Z; Kattadiyil, Mathew T

2016-08-01

Currently no data comparing the denture base adaptation of CAD-CAM and conventional denture processing techniques have been reported. The purpose of this in vitro study was to compare the denture base adaptation of pack and press, pour, injection, and CAD-CAM techniques for fabricating dentures to determine which process produces the most accurate and reproducible adaptation. A definitive cast was duplicated to create 40 gypsum casts that were laser scanned before any fabrication procedures were initiated. A master denture was made using the CAD-CAM process and was then used to create a putty mold for the fabrication of 30 standardized wax festooned dentures, 10 for each of the conventional processing techniques (pack and press, pour, injection). Scan files from 10 casts were sent to Global Dental Science, LLC for fabrication of the CAD-CAM test specimens. After specimens for each of the 4 techniques had been fabricated, they were hydrated for 24 hours and the intaglio surface laser scanned. The scan file of each denture was superimposed on the scan file of the corresponding preprocessing cast using surface matching software. Measurements were made at 60 locations, providing evaluation of fit discrepancies at the following areas: apex of the denture border, 6 mm from the denture border, crest of the ridge, palate, and posterior palatal seal. The use of median and interquartile range was used to assess accuracy and reproducibility. The Levine and Kruskal-Wallis analysis of variance was used to evaluate differences between processing techniques at the 5 specified locations (α=.05). The ranking of results based on median and interquartile range determined that the accuracy and reproducibility of the CAD-CAM technique was more consistently localized around zero at 3 of the 5 locations. Therefore, the CAD-CAM technique showed the best combination of accuracy and reproducibility among the tested fabrication techniques. The pack and press technique was more accurate at

Black carbon aerosol mixing state, organic aerosols and aerosol optical properties over the United Kingdom

NASA Astrophysics Data System (ADS)

McMeeking, G. R.; Morgan, W. T.; Flynn, M.; Highwood, E. J.; Turnbull, K.; Haywood, J.; Coe, H.

2011-09-01

Black carbon (BC) aerosols absorb sunlight thereby leading to a positive radiative forcing and a warming of climate and can also impact human health through their impact on the respiratory system. The state of mixing of BC with other aerosol species, particularly the degree of internal/external mixing, has been highlighted as a major uncertainty in assessing its radiative forcing and hence its climate impact, but few in situ observations of mixing state exist. We present airborne single particle soot photometer (SP2) measurements of refractory BC (rBC) mass concentrations and mixing state coupled with aerosol composition and optical properties measured in urban plumes and regional pollution over the United Kingdom. All data were obtained using instrumentation flown on the UK's BAe-146-301 large Atmospheric Research Aircraft (ARA) operated by the Facility for Airborne Atmospheric Measurements (FAAM). We measured sub-micron aerosol composition using an aerosol mass spectrometer (AMS) and used positive matrix factorization to separate hydrocarbon-like (HOA) and oxygenated organic aerosols (OOA). We found a higher number fraction of thickly coated rBC particles in air masses with large OOA relative to HOA, higher ozone-to-nitrogen oxides (NOx) ratios and large concentrations of total sub-micron aerosol mass relative to rBC mass concentrations. The more ozone- and OOA-rich air masses were associated with transport from continental Europe, while plumes from UK cities had higher HOA and NOx and fewer thickly coated rBC particles. We did not observe any significant change in the rBC mass absorption efficiency calculated from rBC mass and light absorption coefficients measured by a particle soot absorption photometer despite observing significant changes in aerosol composition and rBC mixing state. The contributions of light scattering and absorption to total extinction (quantified by the single scattering albedo; SSA) did change for different air masses, with lower SSA

CAD-CAE in Electrical Machines and Drives Teaching.

ERIC Educational Resources Information Center

Belmans, R.; Geysen, W.

1988-01-01

Describes the use of computer-aided design (CAD) techniques in teaching the design of electrical motors. Approaches described include three technical viewpoints, such as electromagnetics, thermal, and mechanical aspects. Provides three diagrams, a table, and conclusions. (YP)

Characterization of urban aerosol in Cork city (Ireland) using aerosol mass spectrometry

NASA Astrophysics Data System (ADS)

Dall'Osto, M.; Ovadnevaite, J.; Ceburnis, D.; Martin, D.; Healy, R. M.; O'Connor, I. P.; Kourtchev, I.; Sodeau, J. R.; Wenger, J. C.; O'Dowd, C.

2013-05-01

Ambient wintertime background urban aerosol in Cork city, Ireland, was characterized using aerosol mass spectrometry. During the three-week measurement study in 2009, 93% of the ca. 1 350 000 single particles characterized by an Aerosol Time-of-Flight Mass Spectrometer (TSI ATOFMS) were classified into five organic-rich particle types, internally mixed to different proportions with elemental carbon (EC), sulphate and nitrate, while the remaining 7% was predominantly inorganic in nature. Non-refractory PM1 aerosol was characterized using a High Resolution Time-of-Flight Aerosol Mass Spectrometer (Aerodyne HR-ToF-AMS) and was also found to comprise organic aerosol as the most abundant species (62%), followed by nitrate (15%), sulphate (9%) and ammonium (9%), and chloride (5%). Positive matrix factorization (PMF) was applied to the HR-ToF-AMS organic matrix, and a five-factor solution was found to describe the variance in the data well. Specifically, "hydrocarbon-like" organic aerosol (HOA) comprised 20% of the mass, "low-volatility" oxygenated organic aerosol (LV-OOA) comprised 18%, "biomass burning" organic aerosol (BBOA) comprised 23%, non-wood solid-fuel combustion "peat and coal" organic aerosol (PCOA) comprised 21%, and finally a species type characterized by primary {m/z} peaks at 41 and 55, similar to previously reported "cooking" organic aerosol (COA), but possessing different diurnal variations to what would be expected for cooking activities, contributed 18%. Correlations between the different particle types obtained by the two aerosol mass spectrometers are also discussed. Despite wood, coal and peat being minor fuel types used for domestic space heating in urban areas, their relatively low combustion efficiencies result in a significant contribution to PM1 aerosol mass (44% and 28% of the total organic aerosol mass and non-refractory total PM1, respectively).

Estimating Marine Aerosol Particle Volume and Number from Maritime Aerosol Network Data

NASA Technical Reports Server (NTRS)

Sayer, A. M.; Smirnov, A.; Hsu, N. C.; Munchak, L. A.; Holben, B. N.

2012-01-01

As well as spectral aerosol optical depth (AOD), aerosol composition and concentration (number, volume, or mass) are of interest for a variety of applications. However, remote sensing of these quantities is more difficult than for AOD, as it is more sensitive to assumptions relating to aerosol composition. This study uses spectral AOD measured on Maritime Aerosol Network (MAN) cruises, with the additional constraint of a microphysical model for unpolluted maritime aerosol based on analysis of Aerosol Robotic Network (AERONET) inversions, to estimate these quantities over open ocean. When the MAN data are subset to those likely to be comprised of maritime aerosol, number and volume concentrations obtained are physically reasonable. Attempts to estimate surface concentration from columnar abundance, however, are shown to be limited by uncertainties in vertical distribution. Columnar AOD at 550 nm and aerosol number for unpolluted maritime cases are also compared with Moderate Resolution Imaging Spectroradiometer (MODIS) data, for both the present Collection 5.1 and forthcoming Collection 6. MODIS provides a best-fitting retrieval solution, as well as the average for several different solutions, with different aerosol microphysical models. The average solution MODIS dataset agrees more closely with MAN than the best solution dataset. Terra tends to retrieve lower aerosol number than MAN, and Aqua higher, linked with differences in the aerosol models commonly chosen. Collection 6 AOD is likely to agree more closely with MAN over open ocean than Collection 5.1. In situations where spectral AOD is measured accurately, and aerosol microphysical properties are reasonably well-constrained, estimates of aerosol number and volume using MAN or similar data would provide for a greater variety of potential comparisons with aerosol properties derived from satellite or chemistry transport model data.

Understanding dental CAD/CAM for restorations--the digital workflow from a mechanical engineering viewpoint.

PubMed

Tapie, L; Lebon, N; Mawussi, B; Fron Chabouis, H; Duret, F; Attal, J-P

2015-01-01

As digital technology infiltrates every area of daily life, including the field of medicine, so it is increasingly being introduced into dental practice. Apart from chairside practice, computer-aided design/computer-aided manufacturing (CAD/CAM) solutions are available for creating inlays, crowns, fixed partial dentures (FPDs), implant abutments, and other dental prostheses. CAD/CAM dental solutions can be considered a chain of digital devices and software for the almost automatic design and creation of dental restorations. However, dentists who want to use the technology often do not have the time or knowledge to understand it. A basic knowledge of the CAD/CAM digital workflow for dental restorations can help dentists to grasp the technology and purchase a CAM/CAM system that meets the needs of their office. This article provides a computer-science and mechanical-engineering approach to the CAD/CAM digital workflow to help dentists understand the technology.

The CD4/CD8 ratio is associated with coronary artery disease (CAD) in elderly Chinese patients.

PubMed

Gao, Pan; Rong, Hong-Hui; Lu, Ting; Tang, Gang; Si, Liang-Yi; Lederer, James A; Xiong, Wei

2017-01-01

The aim of this study was to investigate the relationship between number of circulating T cells and coronary artery disease (CAD) in an elderly Chinese population. A total of 295 elderly inpatients (age≥60) were included in this cross-sectional study. Their clinical and biochemical characteristics were recorded. Patients were divided to two groups: control patients and CAD patients. The risk factors of CAD were explored by binary logistic regression analysis. Compared with control patients, the ratio of CD4 to CD8 T cells was significantly increased in CAD patients. There was no difference in the number of CD3, CD4, and CD8 T cells between the two groups. Multiple logistic regression analysis showed that CAD was independently associated with age, gender, body mass index (BMI), systolic blood pressure (SBP), chronic heart failure (CHF) and the CD4/CD8 ratio. In addition, after adjusting for different clinical parameters (including gender, age, CHF, hypertension, arrhythmia, SBP, and BMI), the risk of CAD was significantly increased in patients with a CD4/CD8 ratio>1.5. There was a strong and independent association between the ratio of CD4/CD8 and CAD in elderly Chinese population. Copyright © 2016. Published by Elsevier B.V.

Research on AutoCAD secondary development and function expansion based on VBA technology

NASA Astrophysics Data System (ADS)

Zhang, Runmei; Gu, Yehuan

2017-06-01

AutoCAD is the most widely used drawing tool among the similar design drawing products. In the process of drawing different types of design drawings of the same product, there are a lot of repetitive and single work contents. The traditional manual method uses a drawing software AutoCAD drawing graphics with low efficiency, high error rate and high input cost shortcomings and many more. In order to solve these problems, the design of the parametric drawing system of the hot-rolled I-beam (steel beam) cross-section is completed by using the VBA secondary development tool and the Access database software with large-capacity storage data, and the analysis of the functional extension of the plane drawing and the parametric drawing design in this paper. For the secondary development of AutoCAD functions, the system drawing work will be simplified and work efficiency also has been greatly improved. This introduction of parametric design of AutoCAD drawing system to promote the industrial mass production and related industries economic growth rate similar to the standard I-beam hot-rolled products.

Fracture analysis of CAD-CAM high-density polymers used for interim implant-supported fixed, cantilevered prostheses.

PubMed

Yilmaz, Burak; Alp, Gülce; Seidt, Jeremy; Johnston, William M; Vitter, Roger; McGlumphy, Edwin A

2018-01-06

The load-to-fracture performance of computer-assisted design and computer-assisted manufacturing (CAD-CAM) high-density polymer (HDP) materials in cantilevers is unknown. The purposes of this in vitro study were to evaluate the load-to-fracture performance of CAD-CAM-fabricated HDPs and to compare that with performance of autopolymerized and injection-molded acrylic resins. Specimens from 8 different brands of CAD-CAM HDPs, including Brylic Solid (BS); Brylic Gradient (BG); AnaxCAD Temp EZ (AE); AnaxCAD Temp Plus (AP); Zirkonzahn Temp Basic (Z); GDS Tempo-CAD (GD); Polident (Po); Merz M-PM-Disc (MAT); an autopolymerized acrylic resin, Imident (Conv) and an injection-molded acrylic resin, SR-IvoBase High Impact (Inj) were evaluated for load-to-fracture analysis (n=5). CAD-CAM specimens were milled from poly(methyl methacrylate) (PMMA) blocks measuring 7 mm in buccolingual width, 8 mm in occlusocervical thickness, and 30 mm in length. A wax pattern was prepared in the same dimensions used for CAD-CAM specimens, flasked, and boiled out. Autopolymerizing acrylic resin was packed and polymerized in a pressure container for 30 minutes. An identical wax pattern was flasked and boiled out, and premeasured capsules were injected (SR-IvoBase) and polymerized under hydraulic pressure for 35 minutes for the injection-molded PMMA. Specimens were thermocycled 5000 times (5°C to 55°C) and fixed to a universal testing machine to receive static loads on the 10-mm cantilever, vertically at a 1 mm/min crosshead speed until fracture occurred. Maximum load-to-fracture values were recorded. ANOVA was used to analyze the maximum force values. Significant differences among materials were analyzed by using the Ryan-Einot-Gabriel-Welsch multiple range test (α=.05). Statistically significant differences were found among load-to-fracture values of different HDPs (P<.001). GD and Po materials had significantly higher load-to-fracture values than other materials (P<.001), and no

Project Integration Architecture (PIA) and Computational Analysis Programming Interface (CAPRI) for Accessing Geometry Data from CAD Files

NASA Technical Reports Server (NTRS)

Benyo, Theresa L.

2002-01-01

Integration of a supersonic inlet simulation with a computer aided design (CAD) system is demonstrated. The integration is performed using the Project Integration Architecture (PIA). PIA provides a common environment for wrapping many types of applications. Accessing geometry data from CAD files is accomplished by incorporating appropriate function calls from the Computational Analysis Programming Interface (CAPRI). CAPRI is a CAD vendor neutral programming interface that aids in acquiring geometry data directly from CAD files. The benefits of wrapping a supersonic inlet simulation into PIA using CAPRI are; direct access of geometry data, accurate capture of geometry data, automatic conversion of data units, CAD vendor neutral operation, and on-line interactive history capture. This paper describes the PIA and the CAPRI wrapper and details the supersonic inlet simulation demonstration.

On the Use of Parmetric-CAD Systems and Cartesian Methods for Aerodynamic Design

NASA Technical Reports Server (NTRS)

Nemec, Marian; Aftosmis, Michael J.; Pulliam, Thomas H.

2004-01-01

Automated, high-fidelity tools for aerodynamic design face critical issues in attempting to optimize real-life geometry arid in permitting radical design changes. Success in these areas promises not only significantly shorter design- cycle times, but also superior and unconventional designs. To address these issues, we investigate the use of a parmetric-CAD system in conjunction with an embedded-boundary Cartesian method. Our goal is to combine the modeling capabilities of feature-based CAD with the robustness and flexibility of component-based Cartesian volume-mesh generation for complex geometry problems. We present the development of an automated optimization frame-work with a focus on the deployment of such a CAD-based design approach in a heterogeneous parallel computing environment.

Aerodynamic Design of Complex Configurations Using Cartesian Methods and CAD Geometry

NASA Technical Reports Server (NTRS)

Nemec, Marian; Aftosmis, Michael J.; Pulliam, Thomas H.

2003-01-01

The objective for this paper is to present the development of an optimization capability for the Cartesian inviscid-flow analysis package of Aftosmis et al. We evaluate and characterize the following modules within the new optimization framework: (1) A component-based geometry parameterization approach using a CAD solid representation and the CAPRI interface. (2) The use of Cartesian methods in the development Optimization techniques using a genetic algorithm. The discussion and investigations focus on several real world problems of the optimization process. We examine the architectural issues associated with the deployment of a CAD-based design approach in a heterogeneous parallel computing environment that contains both CAD workstations and dedicated compute nodes. In addition, we study the influence of noise on the performance of optimization techniques, and the overall efficiency of the optimization process for aerodynamic design of complex three-dimensional configurations. of automated optimization tools. rithm and a gradient-based algorithm.

Utilization of CAD/CAE for concurrent design of structural aircraft components

NASA Technical Reports Server (NTRS)

Kahn, William C.

1993-01-01

The feasibility of installing the Stratospheric Observatory for Infrared Astronomy telescope (named SOFIA) into an aircraft for NASA astronomy studies is investigated using CAD/CAE equipment to either design or supply data for every facet of design engineering. The aircraft selected for the platform was a Boeing 747, chosen on the basis of its ability to meet the flight profiles required for the given mission and payload. CAD models of the fuselage of two of the aircraft models studied (747-200 and 747 SP) were developed, and models for the component parts of the telescope and subsystems were developed by the various concurrent engineering groups of the SOFIA program, to determine the requirements for the cavity opening and for design configuration. It is noted that, by developing a plan to use CAD/CAE for concurrent engineering at the beginning of the study, it was possible to produce results in about two-thirds of the time required using traditional methods.

Mechanical properties and internal fit of 4 CAD-CAM block materials.

PubMed

Goujat, Alexis; Abouelleil, Hazem; Colon, Pierre; Jeannin, Christophe; Pradelle, Nelly; Seux, Dominique; Grosgogeat, Brigitte

2018-03-01

Recent polymer-based computer-assisted design and computer-assisted manufacturing (CAD-CAM) materials have been commercialized for inlay restorations, a polymer-infiltrated ceramic-network (PICN) and composite resin nanoceramics. Little independent evidence regarding their mechanical properties exists. Internal adaptation is an important factor for the clinical success and longevity of a restoration, and data concerning this parameter for inlays made with these blocks are scarce. The purpose of this in vitro study was to evaluate and compare the mechanical properties (flexural strength, flexural modulus, Vickers hardness, fracture toughness) and the internal adaptation of these recent polymer-based blocks with a lithium disilicate glass-ceramic block. The materials tested in this study were a PICN material (Vita Enamic), 2 composite resin nanoceramics (Lava Ultimate; 3M ESPE and Cerasmart; GCDental Products), and a lithium disilicate glass-ceramic (IPS e.max CAD). Mechanical properties were evaluated according to ISO norm DIS 6872:2013. Bar-shaped specimens (18×3×3 mm) were prepared and submitted to a 3-point bend test using a universal testing machine at a cross-head speed of 0.5 mm/min. In addition, identical cavities were prepared in 60 human mandibular extracted molars (n=15) and optically scanned to receive mesioocclusodistal inlays milled with the 4 materials tested in a CEREC Inlab milling machine. The replica technique and a stereomicroscope (×20) were used to measure the internal fit of the inlays at 9 preselected locations. All data were statistically analyzed using 1-way ANOVA and the post hoc Tukey multiple comparison or Games-Howell test (α=.05). The mean flexural strength of the tested blocks ranged from 148.7 ±9.5 MPa (Vita Enamic) to 216.5 ±28.3 MPa (Cerasmart). The mean flexural modulus ranged from 23.3 ±6.4 GPa (Vita Enamic) to 52.8 ±10.5 GPa (IPS e.max CAD). The mean Vickers hardness ranged from 0.66 ±0.02 GPa (Cerasmart) to 5.98 ±0

Digital Sketch Modelling: Integrating Digital Sketching as a Transition between Sketching and CAD in Industrial Design Education

ERIC Educational Resources Information Center

Ranscombe, Charlie; Bissett-Johnson, Katherine

2017-01-01

Literature on the use of design tools in educational settings notes an uneasy relationship between student use of traditional hand sketching and digital modelling tools (CAD) during the industrial design process. This is often manifested in the transition from sketching to CAD and exacerbated by a preference of current students to use CAD. In this…

Aerosols

Atmospheric Science Data Center

2013-04-17

... depth. A color scale is used to represent this quantity, and high aerosol amount is indicated by yellow or green pixels, and clearer skies ... out most clearly, whereas MISR's oblique cameras enhance sensitivity to even thin layers of aerosols. In the March image, the only ...

The Effect of Molar Axial Wall Height on CAD/CAM Ceramic Crowns With Moderate Occlusal Convergence

DTIC Science & Technology

2006-05-01

CEREC e.max* CAD crowns on preparations with moderate total occlusal convergence (16 degrees). Methods: 60 recently-extracted maxillary third molars ...The Effect of Molar Axial Wall Height on CAD/CAM Ceramic Crowns With Moderate Occlusal Convergence Wyeth L. Hoopes The Effect of Molar Axial Wall... Molar Axial Wall Height on CAD/CAM Ceramic Crowns With Moderate Occlusal Convergence is appropria tely acknowledged and beyond brief excerpts, is with

Rapid Measurements of Aerosol Size Distribution and Hygroscopic Growth via Image Processing with a Fast Integrated Mobility Spectrometer (FIMS)

NASA Astrophysics Data System (ADS)

Wang, Y.; Pinterich, T.; Spielman, S. R.; Hering, S. V.; Wang, J.

2017-12-01

Aerosol size distribution and hygroscopicity are among key parameters in determining the impact of atmospheric aerosols on global radiation and climate change. In situ submicron aerosol size distribution measurements commonly involve a scanning mobility particle sizer (SMPS). The SMPS scanning time is in the scale of minutes, which is often too slow to capture the variation of aerosol size distribution, such as for aerosols formed via nucleation processes or measurements onboard research aircraft. To solve this problem, a Fast Integrated Mobility Spectrometer (FIMS) based on image processing was developed for rapid measurements of aerosol size distributions from 10 to 500 nm. The FIMS consists of a parallel plate classifier, a condenser, and a CCD detector array. Inside the classifier an electric field separates charged aerosols based on electrical mobilities. Upon exiting the classifier, the aerosols pass through a three stage growth channel (Pinterich et al. 2017; Spielman et al. 2017), where aerosols as small as 7 nm are enlarged to above 1 μm through water or heptanol condensation. Finally, the grown aerosols are illuminated by a laser sheet and imaged onto a CCD array. The images provide both aerosol concentration and position, which directly relate to the aerosol size distribution. By this simultaneous measurement of aerosols with different sizes, the FIMS provides aerosol size spectra nearly 100 times faster than the SMPS. Recent deployment onboard research aircraft demonstrated that the FIMS is capable of measuring aerosol size distributions in 1s (Figure), thereby offering a great advantage in applications requiring high time resolution (Wang et al. 2016). In addition, the coupling of the FIMS with other conventional aerosol instruments provides orders of magnitude more rapid characterization of aerosol optical and microphysical properties. For example, the combination of a differential mobility analyzer, a relative humidity control unit, and a FIMS was

Digital impression and jaw relation record for the fabrication of CAD/CAM custom tray.

PubMed

Kanazawa, Manabu; Iwaki, Maiko; Arakida, Toshio; Minakuchi, Shunsuke

2018-03-16

This article describes the protocol of a digital impression technique to make an impression and recording of the jaw relationship of edentulous patients for the fabrication of CAD/CAM custom tray using computer-aided design and manufacturing (CAD/CAM) technology. Scan the maxillary and mandibular edentulous jaws using an intraoral scanner. Scan the silicone jig with the maxillary and mandibular jaws while keeping the jig between the jaws. Import the standard tessellation language data of the maxillary and mandibular jaws and jig to make a jaw relation record and fabricate custom trays (CAD/CAM trays) using a rapid prototyping system. Make a definitive impression of the maxillary and mandibular jaws using the CAD/CAM trays. Digitalization of the complete denture fabrication process can simplify the complicated treatment and laboratory process of conventional methods In addition, the proposed method enables quality control regardless of the operator's experience and technique. Copyright © 2018. Published by Elsevier Ltd.

ClusterCAD: a computational platform for type I modular polyketide synthase design

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

Eng, Clara H.; Backman, Tyler W H; Bailey, Constance B.

Here, we present ClusterCAD, a web-based toolkit designed to leverage the collinear structure and deterministic logic of type I modular polyketide synthases (PKSs) for synthetic biology applications. The unique organization of these megasynthases, combined with the diversity of their catalytic domain building blocks, has fueled an interest in harnessing the biosynthetic potential of PKSs for the microbial production of both novel natural product analogs and industrially relevant small molecules. However, a limited theoretical understanding of the determinants of PKS fold and function poses a substantial barrier to the design of active variants, and identifying strategies to reliably construct functional PKSmore » chimeras remains an active area of research. In this work, we formalize a paradigm for the design of PKS chimeras and introduce ClusterCAD as a computational platform to streamline and simplify the process of designing experiments to test strategies for engineering PKS variants. ClusterCAD provides chemical structures with stereochemistry for the intermediates generated by each PKS module, as well as sequence- and structure-based search tools that allow users to identify modules based either on amino acid sequence or on the chemical structure of the cognate polyketide intermediate. ClusterCAD can be accessed at https://clustercad.jbei.org and at http://clustercad.igb.uci.edu.« less

ClusterCAD: a computational platform for type I modular polyketide synthase design

DOE PAGES

Eng, Clara H.; Backman, Tyler W H; Bailey, Constance B.; ...

2017-10-11

Here, we present ClusterCAD, a web-based toolkit designed to leverage the collinear structure and deterministic logic of type I modular polyketide synthases (PKSs) for synthetic biology applications. The unique organization of these megasynthases, combined with the diversity of their catalytic domain building blocks, has fueled an interest in harnessing the biosynthetic potential of PKSs for the microbial production of both novel natural product analogs and industrially relevant small molecules. However, a limited theoretical understanding of the determinants of PKS fold and function poses a substantial barrier to the design of active variants, and identifying strategies to reliably construct functional PKSmore » chimeras remains an active area of research. In this work, we formalize a paradigm for the design of PKS chimeras and introduce ClusterCAD as a computational platform to streamline and simplify the process of designing experiments to test strategies for engineering PKS variants. ClusterCAD provides chemical structures with stereochemistry for the intermediates generated by each PKS module, as well as sequence- and structure-based search tools that allow users to identify modules based either on amino acid sequence or on the chemical structure of the cognate polyketide intermediate. ClusterCAD can be accessed at https://clustercad.jbei.org and at http://clustercad.igb.uci.edu.« less

Sources and Variability of Aerosols and Aerosol-Cloud Interactions in the Arctic

NASA Astrophysics Data System (ADS)

Liu, H.; Zhang, B.; Taylor, P. C.; Moore, R.; Barahona, D.; Fairlie, T. D.; Chen, G.; Ham, S. H.; Kato, S.

2017-12-01

Arctic sea ice in recent decades has significantly declined. This requires understanding of the Arctic surface energy balance, of which clouds are a major driver. However, the mechanisms for the formation and evolution of clouds in the Arctic and the roles of aerosols therein are highly uncertain. Here we conduct data analysis and global model simulations to examine the sources and variability of aerosols and aerosol-cloud interactions in the Arctic. We use the MERRA-2 reanalysis data (2006-present) from the NASA Global Modeling and Assimilation Office (GMAO) to (1) quantify contributions of different aerosol types to the aerosol budget and aerosol optical depths in the Arctic, (2) ­examine aerosol distributions and variability and diagnose the major pathways for mid-latitude pollution transport to the Arctic, including their seasonal and interannual variability, and (3) characterize the distribution and variability of clouds (cloud optical depth, cloud fraction, cloud liquid and ice water path, cloud top height) in the Arctic. We compare MERRA-2 aerosol and cloud properties with those from C3M, a 3-D aerosol and cloud data product developed at NASA Langley Research Center and merged from multiple A-Train satellite (CERES, CloudSat, CALIPSO, and MODIS) observations. We also conduct perturbation experiments using the NASA GEOS-5 chemistry-climate model (with GOCART aerosol module coupled with two-moment cloud microphysics), and discuss the roles of various types of aerosols in the formation and evolution of clouds in the Arctic.

Demonstration of a diode-laser-based high spectral resolution lidar (HSRL) for quantitative profiling of clouds and aerosols.

PubMed

Hayman, Matthew; Spuler, Scott

2017-11-27

We present a demonstration of a diode-laser-based high spectral resolution lidar. It is capable of performing calibrated retrievals of aerosol and cloud optical properties at a 150 m range resolution with less than 1 minute integration time over an approximate range of 12 km during day and night. This instrument operates at 780 nm, a wavelength that is well established for reliable semiconductor lasers and detectors, and was chosen because it corresponds to the D2 rubidium absorption line. A heated vapor reference cell of isotopic rubidium 87 is used as an effective and reliable aerosol signal blocking filter in the instrument. In principle, the diode-laser-based high spectral resolution lidar can be made cost competitive with elastic backscatter lidar systems, yet delivers a significant improvement in data quality through direct retrieval of quantitative optical properties of clouds and aerosols.

Aerosol Indirect Effects on Cirrus Clouds in Global Aerosol-Climate Models

NASA Astrophysics Data System (ADS)

Liu, X.; Zhang, K.; Wang, Y.; Neubauer, D.; Lohmann, U.; Ferrachat, S.; Zhou, C.; Penner, J.; Barahona, D.; Shi, X.

2015-12-01

Cirrus clouds play an important role in regulating the Earth's radiative budget and water vapor distribution in the upper troposphere. Aerosols can act as solution droplets or ice nuclei that promote ice nucleation in cirrus clouds. Anthropogenic emissions from fossil fuel and biomass burning activities have substantially perturbed and enhanced concentrations of aerosol particles in the atmosphere. Global aerosol-climate models (GCMs) have now been used to quantify the radiative forcing and effects of aerosols on cirrus clouds (IPCC AR5). However, the estimate uncertainty is very large due to the different representation of ice cloud formation and evolution processes in GCMs. In addition, large discrepancies have been found between model simulations in terms of the spatial distribution of ice-nucleating aerosols, relative humidity, and temperature fluctuations, which contribute to different estimates of the aerosol indirect effect through cirrus clouds. In this presentation, four GCMs with the start-of-the art representations of cloud microphysics and aerosol-cloud interactions are used to estimate the aerosol indirect effects on cirrus clouds and to identify the causes of the discrepancies. The estimated global and annual mean anthropogenic aerosol indirect effect through cirrus clouds ranges from 0.1 W m-2 to 0.3 W m-2 in terms of the top-of-the-atmosphere (TOA) net radiation flux, and 0.5-0.6 W m-2 for the TOA longwave flux. Despite the good agreement on global mean, large discrepancies are found at the regional scale. The physics behind the aerosol indirect effect is dramatically different. Our analysis suggests that burden of ice-nucleating aerosols in the upper troposphere, ice nucleation frequency, and relative role of ice formation processes (i.e., homogeneous versus heterogeneous nucleation) play key roles in determining the characteristics of the simulated aerosol indirect effects. In addition to the indirect effect estimate, we also use field campaign

Colour parameters and shade correspondence of CAD-CAM ceramic systems.

PubMed

Della Bona, Alvaro; Pecho, Oscar E; Ghinea, Razvan; Cardona, Juan C; Pérez, María M

2015-06-01

To evaluate colour differences between (1) CAD-CAM ceramic systems considering shades A1, A2 and A3 and the corresponding nominal shade of VC (Vita Classical shade guide) and (2) shades A1-A2, A2-A3 and A1, A2 and A3 within the same ceramic system. Samples of shades A1, A2 and A3 were fabricated (n=5) from CAD-CAM ceramic blocks (IPS e.max(®) CAD LT and HT, IPS Empress(®) CAD LT and HT, Paradigm™ C, and VITABLOCS(®) Mark II) and polished to 1.0±0.01mm in thickness. Spectral reflectance and colour coordinates were measured using a spectroradiometer inside a viewing booth using the CIE D65 illuminant and the d/0° geometry. Spectral reflectance curves were compared using VAF coefficient and were statistically analyzed using Kruskal-Wallis and the Mann-Whitney U test (α=0.05). Colour coordinates were statistically analyzed using one-way ANOVA, Tukey's test with Bonferroni correction (α=0.001). All colour differences (ΔEab(*) and ΔE00) were analyzed through comparisons with the PT - perceptibility and AT - acceptability thresholds for dental ceramics. ΔE between ceramic systems and its corresponding shade ranged from 6.32 to 13.42 (ΔEab(*)) and 4.48 to 9.30 (ΔE00). ΔE between shades A1-A2, A2-A3 and A1, A2 and A3 ranged, respectively, 1.93-4.82, 1.22-5.59 and 3.63-8.84 (ΔEab(*)); 1.54-3.87, 1.03-3.90 and 2.95-6.51 (ΔE00). Considering the corresponding nominal shade from VC, none of the ceramic systems showed colour differences below the AT. In addition, some ceramic systems showed colour differences below AT (shades A1-A2 and A2-A3) and below PT (shades A2-A3). Careful adjustments should be made to the final shade of CAD-CAM ceramic restorations to reach a clinically acceptable shade match. Copyright © 2015 Elsevier Ltd. All rights reserved.

Characterization of urban aerosol in Cork City (Ireland) using aerosol mass spectrometry

NASA Astrophysics Data System (ADS)

Dall'Osto, M.; Ovadnevaite, J.; Ceburnis, D.; Martin, D.; Healy, R. M.; O'Connor, I. P.; Sodeau, J. R.; Wenger, J. C.; O'Dowd, C.

2012-11-01

Ambient wintertime background urban aerosol in Cork City, Ireland, was characterized using aerosol mass spectrometry. During the three-week measurement study in 2009, 93% of the 1 200 000 single particles characterized by an Aerosol Time-Of-Flight Mass Spectrometer (TSI ATOFMS) were classified into five organic-rich particle types, internally-mixed to different proportions with Elemental Carbon (EC), sulphate and nitrate while the remaining 7% was predominantly inorganic in nature. Non-refractory PM1 aerosol was also characterized using a High Resolution Time-Of-Flight Aerodyne Aerosol Mass Spectrometer (HR-ToF-AMS) and was also found to comprise organic matter as the most abundant species (62%), followed by nitrate (15%), sulphate (9%) and ammonium (9%), and then chloride (5%). Positive matrix factorization (PMF) was applied to the HR-ToF-AMS organic matrix and a five-factor solution was found to describe the variance in the data well. Specifically, "Hydrocarbon-like" Organic Aerosol (HOA) comprised 19% of the mass, "Oxygenated low volatility" Organic Aerosols (LV-OOA) comprised 19%, "Biomass wood Burning" Organic Aerosol (BBOA) comprised 23%, non-wood solid-fuel combustion "Peat and Coal" Organic Aerosol (PCOA) comprised 21%, and finally, a species type characterized by primary m/z peaks at 41 and 55, similar to previously-reported "Cooking" Organic Aerosol (COA) but possessing different diurnal variations to what would be expected for cooking activities, contributed 18%. Despite wood, cool and peat being minor fuel types used for domestic space heating in urban areas, their relatively low combustion efficiencies result in a significant contribution to PM1 aerosol mass (44% and 28% of the total organic aerosols mass and non refractory PM1, respectively).

The effect of milling and postmilling procedures on the surface roughness of CAD/CAM materials.

PubMed

Mota, Eduardo Gonçalves; Smidt, Laura Nunes; Fracasso, Lisiane Martins; Burnett, Luiz Henrique; Spohr, Ana Maria

2017-11-12

The aim of this study was to evaluate the surface roughness and analyze the surface topography of five different CAD/CAM ceramics and one CAD/CAM composite resin for CEREC after milling and postmilling procedures. Blocks of the ceramics Mark II, IPS Empress CAD, IPS e.max CAD, Suprinity and Enamic, and blocks of the composite resin Lava Ultimate were milled at CEREC MCXL. Ten flat samples of each material were obtained. The surface roughness (Ra) test was performed before and after milling, crystallization, polishing, and glaze when indicated, followed by SEM and AFM analysis. Data were submitted to one-way ANOVA with repeated measures and the Tukey HSD test (α = 0.05). The milling step significantly increased the roughness of all the tested materials (P < .05). Lithium-based ceramics (IPS e.max CAD and Suprinity) were more suitable to roughness than the other tested materials (P < .05). The polishing methods were able to reduce roughness to baseline values, except for lithium-based ceramics. Glaze reduced significantly the roughness of lithium-based ceramics without a difference from the baseline. SEM and AFM images revealed that glazed surfaces are smoother than polished surfaces. All hard-milling CAD/CAM materials, that is, fully sintered, should be only hand polished. The glaze step can be suppressed resulting in time saving. However, the glaze step in soft-milling lithium disilicate is imperative. © 2017 Wiley Periodicals, Inc.

A CAD system and quality assurance protocol for bone age assessment utilizing digital hand atlas

NASA Astrophysics Data System (ADS)

Gertych, Arakadiusz; Zhang, Aifeng; Ferrara, Benjamin; Liu, Brent J.

2007-03-01

Determination of bone age assessment (BAA) in pediatric radiology is a task based on detailed analysis of patient's left hand X-ray. The current standard utilized in clinical practice relies on a subjective comparison of the hand with patterns in the book atlas. The computerized approach to BAA (CBAA) utilizes automatic analysis of the regions of interest in the hand image. This procedure is followed by extraction of quantitative features sensitive to skeletal development that are further converted to a bone age value utilizing knowledge from the digital hand atlas (DHA). This also allows providing BAA results resembling current clinical approach. All developed methodologies have been combined into one CAD module with a graphical user interface (GUI). CBAA can also improve the statistical and analytical accuracy based on a clinical work-flow analysis. For this purpose a quality assurance protocol (QAP) has been developed. Implementation of the QAP helped to make the CAD more robust and find images that cannot meet conditions required by DHA standards. Moreover, the entire CAD-DHA system may gain further benefits if clinical acquisition protocol is modified. The goal of this study is to present the performance improvement of the overall CAD-DHA system with QAP and the comparison of the CAD results with chronological age of 1390 normal subjects from the DHA. The CAD workstation can process images from local image database or from a PACS server.

Aerosol Climate Time Series in ESA Aerosol_cci

NASA Astrophysics Data System (ADS)

Popp, Thomas; de Leeuw, Gerrit; Pinnock, Simon

2016-04-01

Within the ESA Climate Change Initiative (CCI) Aerosol_cci (2010 - 2017) conducts intensive work to improve algorithms for the retrieval of aerosol information from European sensors. Meanwhile, full mission time series of 2 GCOS-required aerosol parameters are completely validated and released: Aerosol Optical Depth (AOD) from dual view ATSR-2 / AATSR radiometers (3 algorithms, 1995 - 2012), and stratospheric extinction profiles from star occultation GOMOS spectrometer (2002 - 2012). Additionally, a 35-year multi-sensor time series of the qualitative Absorbing Aerosol Index (AAI) together with sensitivity information and an AAI model simulator is available. Complementary aerosol properties requested by GCOS are in a "round robin" phase, where various algorithms are inter-compared: fine mode AOD, mineral dust AOD (from the thermal IASI spectrometer, but also from ATSR instruments and the POLDER sensor), absorption information and aerosol layer height. As a quasi-reference for validation in few selected regions with sparse ground-based observations the multi-pixel GRASP algorithm for the POLDER instrument is used. Validation of first dataset versions (vs. AERONET, MAN) and inter-comparison to other satellite datasets (MODIS, MISR, SeaWIFS) proved the high quality of the available datasets comparable to other satellite retrievals and revealed needs for algorithm improvement (for example for higher AOD values) which were taken into account for a reprocessing. The datasets contain pixel level uncertainty estimates which were also validated and improved in the reprocessing. For the three ATSR algorithms the use of an ensemble method was tested. The paper will summarize and discuss the status of dataset reprocessing and validation. The focus will be on the ATSR, GOMOS and IASI datasets. Pixel level uncertainties validation will be summarized and discussed including unknown components and their potential usefulness and limitations. Opportunities for time series extension

Wild fire aerosol optical properties measured by lidar at Haifa, Israel

NASA Astrophysics Data System (ADS)

Heese, Birgit; Hofer, Julian; Baars, Holger; Engelmann, Ronny; Althausen, Dietrich; Schechner, Yoav Y.

2018-04-01

Optical properties of fresh biomass burning aerosol were measured by lidar during the wild fires in Israel in November 2016. A single-wavelength lidar Polly was operated at the Technion Campus at Haifa. The detector with originally two channels at 532 and 607 nm was recently upgraded with a cross- and a co-polarised channel at 532 nm, and a rotational Raman channel at 530.2 nm. Preliminary results show high particle depolarisation ratios probably caused by soil dust and large fly-ash particles.

A Case Study in CAD Design Automation

ERIC Educational Resources Information Center

Lowe, Andrew G.; Hartman, Nathan W.

2011-01-01

Computer-aided design (CAD) software and other product life-cycle management (PLM) tools have become ubiquitous in industry during the past 20 years. Over this time they have continuously evolved, becoming programs with enormous capabilities, but the companies that use them have not evolved their design practices at the same rate. Due to the…

Characterization of Florida red tide aerosol and the temporal profile of aerosol concentration.

PubMed

Cheng, Yung Sung; Zhou, Yue; Pierce, Richard H; Henry, Mike; Baden, Daniel G

2010-05-01

Red tide aerosols containing aerosolized brevetoxins are produced during the red tide bloom and transported by wind to coastal areas of Florida. This study reports the characterization of Florida red tide aerosols in human volunteer studies, in which an asthma cohort spent 1h on Siesta Beach (Sarasota, Florida) during aerosolized red tide events and non-exposure periods. Aerosol concentrations, brevetoxin levels, and particle size distribution were measured. Hourly filter samples were taken and analyzed for brevetoxin and NaCl concentrations. In addition, the aerosol mass concentration was monitored in real time. The results indicated that during a non-exposure period in October 2004, no brevetoxin was detected in the water, resulting in non-detectable levels of brevetoxin in the aerosol. In March 2005, the time-averaged concentrations of brevetoxins in water samples were moderate, in the range of 5-10 microg/L, and the corresponding brevetoxin level of Florida red tide aerosol ranged between 21 and 39 ng/m(3). The temporal profiles of red tide aerosol concentration in terms of mass, NaCl, and brevetoxin were in good agreement, indicating that NaCl and brevetoxins are components of the red tide aerosol. By continuously monitoring the marine aerosol and wind direction at Siesta Beach, we observed that the marine aerosol concentration varied as the wind direction changed. The temporal profile of the Florida red tide aerosol during a sampling period could be explained generally with the variation of wind direction. Copyright 2009 Elsevier Ltd. All rights reserved.

CAD/CAM for development and fabrication of cosecant reflector antennas

NASA Astrophysics Data System (ADS)

Petri, U.

The application of CAD/CAM techniques to lower the cost of redesigning and manufacturing specialized cosecant reflector antennas for use in the mm-wave range is described and demonstrated. Consideration is given to the theoretical computation of reflector surfaces; the representation of a reflector surface in a CAD system; the numerically controlled milling of an Al, wood, or plastic model antenna; and the construction of the antenna (by spraying the 300-micron Sn-alloy conducting layer onto the coated model surface and then applying a 1-mm-thick epoxy-matrix GFRP layer, a 20-30-mm layer of flexible polyurethane foam, and a final GFRP layer). Diagrams and photographs are provided.

Analysis of quaternary ammonium and phosphonium ionic liquids by reversed-phase high-performance liquid chromatography with charged aerosol detection and unified calibration.

PubMed

Stojanovic, Anja; Lämmerhofer, Michael; Kogelnig, Daniel; Schiesel, Simone; Sturm, Martin; Galanski, Markus; Krachler, Regina; Keppler, Bernhard K; Lindner, Wolfgang

2008-10-31

Several hydrophobic ionic liquids (ILs) based on long-chain aliphatic ammonium- and phosphonium cations and selected aromatic anions were analyzed by reversed-phase high-performance liquid chromatography (RP-HPLC) employing trifluoroacetic acid as ion-pairing additive to the acetonitrile-containing mobile phase and adopting a step-gradient elution mode. The coupling of charged aerosol detection (CAD) for the non-chromophoric aliphatic cations with diode array detection (DAD) for the aromatic anions allowed their simultaneous analysis in a set of new ILs derived from either tricaprylmethylammonium chloride (Aliquat 336) and trihexyltetradecylphosphonium chloride as precursors. Aliquat 336 is a mix of ammonium cations with distinct aliphatic chain lengths. In the course of the studies it turned out that CAD generates an identical detection response for all the distinct aliphatic cations. Due to lack of single component standards of the individual Aliquat 336 cation species, a unified calibration function was established for the quantitative analysis of the quaternary ammonium cations of the ILs. The developed method was validated according to ICH guidelines, which confirmed the validity of the unified calibration. The application of the method revealed molar ratios of cation to anion close to 1 indicating a quantitative exchange of the chloride ions of the precursors by the various aromatic anions in the course of the synthesis of new ILs. Anomalies of CAD observed for the detection of some aromatic anions (thiosalicylate and benzoate) are discussed.

Aerosol nucleation and growth in the TTL, due to tropical convection, during the ACTIVE campaign

NASA Astrophysics Data System (ADS)

Waddicor, D.; Vaughan, G.; Choularton, T.

2009-04-01

The Aerosol and Chemical Transport In tropical convection (ACTIVE) campaign took place between October 2005 and February 2006. This investigation involved the sampling of deep convective storms that occur in the Tropics; the campaign was based in Darwin, Northern Territory, Australia - the latter half of the campaign coincided with the monsoon season. A range of scientific equipment was used to sample the inflow and outflow air from these storms; of particular importance were the NERC Dornier (low-level) and ARA Egrett (high-level outflow) aircraft. The Dornier held a range of aerosol, particle and chemical detectors for the purpose of analysing the planetary boundary layer (PBL), in the vicinity of tropical convection. The Egrett contained detection instrumentation for a range of sizes of aerosol and cloud particles (2 Condensation Particle Counters (CPC), CAPS, CIP, CPI) in the storm outflow. This allowed a quantifiable measurement to be made of the effect of deep tropical convection on the aerosol population in the Tropical Tropopause Layer (TTL). The ACTIVE campaign found that there were large numbers of aerosol particles in the 10 - 100 nm (up to 25,000 /cm3 STP) and 100 - 1000 nm (up to 600 /cm3) size ranges. These values, in many instances, surpassed those found in the PBL. The higher levels of aerosol found in the TTL compared to the PBL could indicate that aerosol nucleation was occurring in the TTL as a direct result of convective activity. Furthermore, the Egrett aircraft found distinct boundaries between the high levels of aerosol, which were found in cloud free regions, and very low numbers of aerosol, which were found in the cloudy regions (storm anvil). The air masses were determined, from back trajectories, to have been through convective uplift and were formerly part of the anvil cloud. The cloudy regions would have contained high levels of entrapped precursor gases. Reduced nucleation and cloud particle scavenging of aerosol and gases would give a

[Analysis of phthalates in aromatic and deodorant aerosol products and evaluation of exposure risk].

PubMed

Sato, Yoshiki; Sugaya, Naeko; Nakagawa, Tomoo; Morita, Masatoshi

2015-01-01

We established an analytical method for the detection of seven phthalates, dimethyl phthalate, diethyl phthalate (DEP), benzyl butyl phthalate, di-i-butyl phthalate, dibutyl phthalate (DBP), diethylhexyl phthalate (DEHP), and di-n-octhyl phthalate, using an ultra high performance liquid chromatograph equipped with a photodiode array detector. This method is quick, with minimal contamination, and was applied to the analysis of aromatic and deodorant aerosol products. Phthalates were detected in 15 of 52 samples purchased from 1999 to 2012 in Yokohama. Three types of phthalate (DEP, DBP, DEHP) were detected, and their concentrations ranged from 0.0085-0.23% DEP in nine samples, 0.012-0.045% DBP in four samples, and 0.012-0.033% DEHP in four samples. No other phthalate esters were detected. Furthermore, we estimated phthalate exposure via breathing in commonly used aromatic and deodorant aerosol products, then evaluated the associated risk. The estimated levels of phthalate exposure were lower than the tolerated daily limit, but the results indicated that aromatic and deodorant aerosol products could be a significant source of phthalate exposure.

The optical properties of absorbing aerosols with fractal soot aggregates: Implications for aerosol remote sensing

NASA Astrophysics Data System (ADS)

Cheng, Tianhai; Gu, Xingfa; Wu, Yu; Chen, Hao; Yu, Tao

2013-08-01

Applying sphere aerosol models to replace the absorbing fine-sized dominated aerosols can potentially result in significant errors in the climate models and aerosol remote sensing retrieval. In this paper, the optical properties of absorbing fine-sized dominated aerosol were modeled, which are taking into account the fresh emitted soot particles (agglomerates of primary spherules), aged soot particles (semi-externally mixed with other weakly absorbing aerosols), and coarse aerosol particles (dust particles). The optical properties of the individual fresh and aged soot aggregates are calculated using the superposition T-matrix method. In order to quantify the morphology effect of absorbing aerosol models on the aerosol remote sensing retrieval, the ensemble averaged optical properties of absorbing fine-sized dominated aerosols are calculated based on the size distribution of fine aerosols (fresh and aged soot) and coarse aerosols. The corresponding optical properties of sphere absorbing aerosol models using Lorenz-Mie solutions were presented for comparison. The comparison study demonstrates that the sphere absorbing aerosol models underestimate the absorption ability of the fine-sized dominated aerosol particles. The morphology effect of absorbing fine-sized dominated aerosols on the TOA radiances and polarized radiances is also investigated. It is found that the sphere aerosol models overestimate the TOA reflectance and polarized reflectance by approximately a factor of 3 at wavelength of 0.865 μm. In other words, the fine-sized dominated aerosol models can cause large errors in the retrieved aerosol properties if satellite reflectance measurements are analyzed using the conventional Mie theory for spherical particles.

MATRIX-VBS Condensing Organic Aerosols in an Aerosol Microphysics Model

NASA Technical Reports Server (NTRS)

Gao, Chloe Y.; Tsigaridis, Konstas; Bauer, Susanne E.

2015-01-01

The condensation of organic aerosols is represented in a newly developed box-model scheme, where its effect on the growth and composition of particles are examined. We implemented the volatility-basis set (VBS) framework into the aerosol mixing state resolving microphysical scheme Multiconfiguration Aerosol TRacker of mIXing state (MATRIX). This new scheme is unique and advances the representation of organic aerosols in models in that, contrary to the traditional treatment of organic aerosols as non-volatile in most climate models and in the original version of MATRIX, this new scheme treats them as semi-volatile. Such treatment is important because low-volatility organics contribute significantly to the growth of particles. The new scheme includes several classes of semi-volatile organic compounds from the VBS framework that can partition among aerosol populations in MATRIX, thus representing the growth of particles via condensation of low volatility organic vapors. Results from test cases representing Mexico City and a Finish forrest condistions show good representation of the time evolutions of concentration for VBS species in the gas phase and in the condensed particulate phase. Emitted semi-volatile primary organic aerosols evaporate almost completely in the high volatile range, and they condense more efficiently in the low volatility range.

Relationship between fluid bed aerosol generator operation and the aerosol produced

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

Carpenter, R.L.; Yerkes, K.

1980-12-01

The relationships between bed operation in a fluid bed aerosol generator and aerosol output were studied. A two-inch diameter fluid bed aerosol generator (FBG) was constructed using stainless steel powder as a fluidizing medium. Fly ash from coal combustion was aerosolized and the influence of FBG operating parameters on aerosol mass median aerodynamic diameter (MMAD), geometric standard deviation (sigma/sub g/) and concentration was examined. In an effort to extend observations on large fluid beds to small beds using fine bed particles, minimum fluidizing velocities and elutriation constant were computed. Although FBG minimum fluidizing velocity agreed well with calculations, FBG elutriationmore » constant did not. The results of this study show that the properties of aerosols produced by a FBG depend on fluid bed height and air flow through the bed after the minimum fluidizing velocity is exceeded.« less

Effect of staining beverages on color and translucency of CAD/CAM composites.

PubMed

Quek, S H Q; Yap, A U J; Rosa, V; Tan, K B C; Teoh, K H

2018-03-01

This study investigated the color (ΔE) and translucency changes (ΔTP) of CAD/CAM composites after exposure to staining solutions using both spectrophotometer and shade-matching device. Direct (Filtek Z350XT [ZT]), indirect (Shofu Ceramage [CE]) and CAD/CAM (Shofu HC Block [HC], Lava Ultimate [LU], Vita Enamic [EN]) composite specimens measuring 12 × 14 × 1.5 mm were fabricated, divided into five groups (n = 8), and immersed in cola, tea, coffee, red wine, distilled water (control) at 37°C for 7 days. Color parameters were determined with both spectrophotometer and shade-taking device at baseline and 1 week. Delta E (ΔE) with white and black backgrounds, and Delta TP (ΔTP) were computed. Statistical testing was performed with ANOVA and Tukey post hoc test (P < .05). Mean ΔE (white) values ranged from 0.20 ± 0.06 to 12.26 ± 1.95 while mean ΔE (black) varied from 0.22 ± 0.11 to 14.21 ± 2.37. Mean ΔTP values ranged from 0.13 ± 0.17 to -3.87 ± 2.16. CAD/CAM composites fared better in red wine than direct and indirect materials. Clinically perceptible color changes (ΔE > 3.3) were observed for almost all materials when exposed to wine, coffee and tea. Direct, indirect, and CAD/CAM composites are all susceptible to various degrees of discoloration and translucency changes after exposure to staining beverages. Red wine caused the most discoloration and translucency changes. Limitations of these materials must be considered when placing an aesthetic restoration. Direct, indirect, and CAD/CAM composites are all susceptible to various degrees of discoloration and translucency changes after exposure to staining beverages. Red wine generally caused the most discoloration and translucency changes. Although CAD/CAM composites were more color stable than direct and indirect materials when exposed to red wine, color changes were still clinically perceptible. © 2017 Wiley Periodicals, Inc.

Use of Existing CAD Models for Radiation Shielding Analysis

NASA Technical Reports Server (NTRS)

Lee, K. T.; Barzilla, J. E.; Wilson, P.; Davis, A.; Zachman, J.

2015-01-01

The utility of a radiation exposure analysis depends not only on the accuracy of the underlying particle transport code, but also on the accuracy of the geometric representations of both the vehicle used as radiation shielding mass and the phantom representation of the human form. The current NASA/Space Radiation Analysis Group (SRAG) process to determine crew radiation exposure in a vehicle design incorporates both output from an analytic High Z and Energy Particle Transport (HZETRN) code and the properties (i.e., material thicknesses) of a previously processed drawing. This geometry pre-process can be time-consuming, and the results are less accurate than those determined using a Monte Carlo-based particle transport code. The current work aims to improve this process. Although several Monte Carlo programs (FLUKA, Geant4) are readily available, most use an internal geometry engine. The lack of an interface with the standard CAD formats used by the vehicle designers limits the ability of the user to communicate complex geometries. Translation of native CAD drawings into a format readable by these transport programs is time consuming and prone to error. The Direct Accelerated Geometry -United (DAGU) project is intended to provide an interface between the native vehicle or phantom CAD geometry and multiple particle transport codes to minimize problem setup, computing time and analysis error.

Differences in wood density and growth of fertilized and nonfertilized loblolly pine associated with a mutant gene, cad-n1

Treesearch

Q. Yu; S.E. McKeand; C.D. Nelson; B. Li; J.R. Sherrill; T.J. Mullin

2005-01-01

A rare mutant allele (cad-n1) of the cad gene in loblolly pine (Pinus taeda L.) causes a deficiency in the production of cinnamyl alcohol dehydroganase (CAD). Effects associated with this allele were examined by comparing wood density and growth traits of cad-n1 heterozygous trees with those of wild-type trees in a 10-year-old open-pollinated family...

Web-based computer-aided-diagnosis (CAD) system for bone age assessment (BAA) of children

NASA Astrophysics Data System (ADS)

Zhang, Aifeng; Uyeda, Joshua; Tsao, Sinchai; Ma, Kevin; Vachon, Linda A.; Liu, Brent J.; Huang, H. K.

2008-03-01

Bone age assessment (BAA) of children is a clinical procedure frequently performed in pediatric radiology to evaluate the stage of skeletal maturation based on a left hand and wrist radiograph. The most commonly used standard: Greulich and Pyle (G&P) Hand Atlas was developed 50 years ago and exclusively based on Caucasian population. Moreover, inter- & intra-observer discrepancies using this method create a need of an objective and automatic BAA method. A digital hand atlas (DHA) has been collected with 1,400 hand images of normal children from Asian, African American, Caucasian and Hispanic descends. Based on DHA, a fully automatic, objective computer-aided-diagnosis (CAD) method was developed and it was adapted to specific population. To bring DHA and CAD method to the clinical environment as a useful tool in assisting radiologist to achieve higher accuracy in BAA, a web-based system with direct connection to a clinical site is designed as a novel clinical implementation approach for online and real time BAA. The core of the system, a CAD server receives the image from clinical site, processes it by the CAD method and finally, generates report. A web service publishes the results and radiologists at the clinical site can review it online within minutes. This prototype can be easily extended to multiple clinical sites and will provide the foundation for broader use of the CAD system for BAA.

Global Atmospheric Aerosol Modeling

NASA Technical Reports Server (NTRS)

Hendricks, Johannes; Aquila, Valentina; Righi, Mattia

2012-01-01

Global aerosol models are used to study the distribution and properties of atmospheric aerosol particles as well as their effects on clouds, atmospheric chemistry, radiation, and climate. The present article provides an overview of the basic concepts of global atmospheric aerosol modeling and shows some examples from a global aerosol simulation. Particular emphasis is placed on the simulation of aerosol particles and their effects within global climate models.

Aerosol Climate Time Series Evaluation In ESA Aerosol_cci

NASA Astrophysics Data System (ADS)

Popp, T.; de Leeuw, G.; Pinnock, S.

2015-12-01

Within the ESA Climate Change Initiative (CCI) Aerosol_cci (2010 - 2017) conducts intensive work to improve algorithms for the retrieval of aerosol information from European sensors. By the end of 2015 full mission time series of 2 GCOS-required aerosol parameters are completely validated and released: Aerosol Optical Depth (AOD) from dual view ATSR-2 / AATSR radiometers (3 algorithms, 1995 - 2012), and stratospheric extinction profiles from star occultation GOMOS spectrometer (2002 - 2012). Additionally, a 35-year multi-sensor time series of the qualitative Absorbing Aerosol Index (AAI) together with sensitivity information and an AAI model simulator is available. Complementary aerosol properties requested by GCOS are in a "round robin" phase, where various algorithms are inter-compared: fine mode AOD, mineral dust AOD (from the thermal IASI spectrometer), absorption information and aerosol layer height. As a quasi-reference for validation in few selected regions with sparse ground-based observations the multi-pixel GRASP algorithm for the POLDER instrument is used. Validation of first dataset versions (vs. AERONET, MAN) and inter-comparison to other satellite datasets (MODIS, MISR, SeaWIFS) proved the high quality of the available datasets comparable to other satellite retrievals and revealed needs for algorithm improvement (for example for higher AOD values) which were taken into account for a reprocessing. The datasets contain pixel level uncertainty estimates which are also validated. The paper will summarize and discuss the results of major reprocessing and validation conducted in 2015. The focus will be on the ATSR, GOMOS and IASI datasets. Pixel level uncertainties validation will be summarized and discussed including unknown components and their potential usefulness and limitations. Opportunities for time series extension with successor instruments of the Sentinel family will be described and the complementarity of the different satellite aerosol products

Quantification of myocardial blood flow using dynamic 320-row multi-detector CT as compared with ¹⁵O-H₂O PET.

PubMed

Kikuchi, Yasuka; Oyama-Manabe, Noriko; Naya, Masanao; Manabe, Osamu; Tomiyama, Yuuki; Sasaki, Tsukasa; Katoh, Chietsugu; Kudo, Kohsuke; Tamaki, Nagara; Shirato, Hiroki

2014-07-01

This study introduces a method to calculate myocardium blood flow (MBF) and coronary flow reserve (CFR) using the relatively low-dose dynamic 320-row multi-detector computed tomography (MDCT), validates the method against (15)O-H₂O positron-emission tomography (PET) and assesses the CFRs of coronary artery disease (CAD) patients. Thirty-two subjects underwent both dynamic CT perfusion (CTP) and PET perfusion imaging at rest and during pharmacological stress. In 12 normal subjects (pilot group), the calculation method for MBF and CFR was established. In the other 13 normal subjects (validation group), MBF and CFR obtained by dynamic CTP and PET were compared. Finally, the CFRs obtained by dynamic CTP and PET were compared between the validation group and CAD patients (n = 7). Correlation between MBF of MDCT and PET was strong (r = 0.95, P < 0.0001). CFR showed good correlation between dynamic CTP and PET (r = 0.67, P = 0.0126). CFRCT in the CAD group (2.3 ± 0.8) was significantly lower than that in the validation group (5.2 ± 1.8) (P = 0.0011). We established a method for measuring MBF and CFR with the relatively low-dose dynamic MDCT. Lower CFR was well demonstrated in CAD patients by dynamic CTP. • MBF and CFR can be calculated using dynamic CTP with 320-row MDCT. • MBF and CFR showed good correlation between dynamic CTP and PET. • Lower CFR was well demonstrated in CAD patients by dynamic CTP.

A Knowledge Based Approach to VLSI CAD

DTIC Science & Technology

1983-09-01

Avail-and/or Dist ISpecial L| OI. SEICURITY CLASIIrCATION OP THIS IPA.lErllm S Daene." A KNOwLEDE BASED APPROACH TO VLSI CAD’ Louis L Steinberg and...major issues lies in building up and managing the knowledge base of oesign expertise. We expect that, as with many recent expert systems, in order to

A Multidisciplinary Research Team Approach to Computer-Aided Drafting (CAD) System Selection. Final Report.

ERIC Educational Resources Information Center

Franken, Ken; And Others

A multidisciplinary research team was assembled to review existing computer-aided drafting (CAD) systems for the purpose of enabling staff in the Design Drafting Department at Linn Technical College (Missouri) to select the best system out of the many CAD systems in existence. During the initial stage of the evaluation project, researchers…

The Use of a Parametric Feature Based CAD System to Teach Introductory Engineering Graphics.

ERIC Educational Resources Information Center

Howell, Steven K.

1995-01-01

Describes the use of a parametric-feature-based computer-aided design (CAD) System, AutoCAD Designer, in teaching concepts of three dimensional geometrical modeling and design. Allows engineering graphics to go beyond the role of documentation and communication and allows an engineer to actually build a virtual prototype of a design idea and…

Evaluating Aerosol Process Modules within the Framework of the Aerosol Modeling Testbed

NASA Astrophysics Data System (ADS)

Fast, J. D.; Velu, V.; Gustafson, W. I.; Chapman, E.; Easter, R. C.; Shrivastava, M.; Singh, B.

2012-12-01

Factors that influence predictions of aerosol direct and indirect forcing, such as aerosol mass, composition, size distribution, hygroscopicity, and optical properties, still contain large uncertainties in both regional and global models. New aerosol treatments are usually implemented into a 3-D atmospheric model and evaluated using a limited number of measurements from a specific case study. Under this modeling paradigm, the performance and computational efficiency of several treatments for a specific aerosol process cannot be adequately quantified because many other processes among various modeling studies (e.g. grid configuration, meteorology, emission rates) are different as well. The scientific community needs to know the advantages and disadvantages of specific aerosol treatments when the meteorology, chemistry, and other aerosol processes are identical in order to reduce the uncertainties associated with aerosols predictions. To address these issues, an Aerosol Modeling Testbed (AMT) has been developed that systematically and objectively evaluates new aerosol treatments for use in regional and global models. The AMT consists of the modular Weather Research and Forecasting (WRF) model, a series testbed cases for which extensive in situ and remote sensing measurements of meteorological, trace gas, and aerosol properties are available, and a suite of tools to evaluate the performance of meteorological, chemical, aerosol process modules. WRF contains various parameterizations of meteorological, chemical, and aerosol processes and includes interactive aerosol-cloud-radiation treatments similar to those employed by climate models. In addition, the physics suite from the Community Atmosphere Model version 5 (CAM5) have also been ported to WRF so that they can be tested at various spatial scales and compared directly with field campaign data and other parameterizations commonly used by the mesoscale modeling community. Data from several campaigns, including the 2006

Applications of broadband cavity enhanced spectroscopy for measurements of trace gases and aerosols

NASA Astrophysics Data System (ADS)

Washenfelder, R. A.; Attwood, A. R.; Brock, C. A.; Brown, S. S.; Dube, W. P.; Flores, J. M.; Langford, A. O.; Min, K. E.; Rudich, Y.; Stutz, J.; Wagner, N.; Young, C.; Zarzana, K. J.

2015-12-01

Broadband cavity enhanced spectroscopy (BBCES) uses a broadband light source, optical cavity, and multichannel detector to measure light extinction with high sensitivity. This method differs from cavity ringdown spectroscopy, because it uses an inexpensive, incoherent light source and allows optical extinction to be determined simultaneously across a broad wavelength region.Spectral fitting methods can be used to retrieve multiple absorbers across the observed wavelength region. We have successfully used this method to measure glyoxal (CHOCHO), nitrous acid (HONO), and nitrogen dioxide (NO2) from ground-based and aircraft-based sampling platforms. The detection limit (2-sigma) in 5 s for retrievals of CHOCHO, HONO and NO2 is 32, 250 and 80 parts per trillion (pptv).Alternatively, gas-phase absorbers can be chemically removed to allow the accurate determination of aerosol extinction. In the laboratory, we have used the aerosol extinction measurements to determine scattering and absorption as a function of wavelength. We have deployed a ground-based field instrument to measure aerosol extinction, with a detection limit of approximately 0.2 Mm-1 in 1 min.BBCES methods are most widely used in the near-ultraviolet and visible spectral region. Recently, we have demonstrated measurements at 315-350 nm for formaldehyde (CH2O) and NO2. Extending the technique further into the ultraviolet spectral region will allow important additional measurements of trace gas species and aerosol extinction.

Influence of different surface treatments on bond strength of novel CAD/CAM restorative materials to resin cement.

PubMed

Kömürcüoğlu, Meltem Bektaş; Sağırkaya, Elçin; Tulga, Ayça

2017-12-01

To evaluate the effects of different surface treatments on the bond strength of novel CAD/CAM restorative materials to resin cement by four point bending test. The CAD/CAM materials under investigation were e.max CAD, Mark II, Lava Ultimate, and Enamic. A total of 400 bar specimens (4×1.2×12 mm) (n=10) milled from the CAD/CAM blocks underwent various pretreatments (no pretreatment (C), hydrofluoric acid (A), hydrofluoric acid + universal adhesive (Scotchbond) (AS), sandblasting (Sb), and sandblasting + universal adhesive (SbS)). The bars were luted end-to-end on the prepared surfaces with a dual curing adhesive resin cement (Variolink N, Ivoclar Vivadent) on the custom-made stainless steel mold. Ten test specimens for each treatment and material combination were performed with four point bending test method. Data were analyzed using ANOVA and Tukey's test. The surface treatment and type of CAD/CAM restorative material showed a significant effect on the four point bending strength (FPBS) ( P <.001). For LDC, AS surface treatment showed the highest FPBS results (100.31 ± 10.7 MPa) and the lowest values were obtained in RNC (23.63 ± 9.0 MPa) for control group. SEM analyses showed that the surface topography of CAD/CAM restorative materials was modified after treatments. The surface treatment of sandblasting or HF acid etching in combination with a universal adhesive containing MDP can be suggested for the adhesive cementation of the novel CAD/CAM restorative materials.

CAD-CAM plates versus conventional fixation plates for primary mandibular reconstruction: A biomechanical in vitro analysis.

PubMed

Rendenbach, Carsten; Sellenschloh, Kay; Gerbig, Lucca; Morlock, Michael M; Beck-Broichsitter, Benedicta; Smeets, Ralf; Heiland, Max; Huber, Gerd; Hanken, Henning

2017-11-01

CAD/CAM reconstruction plates have become a viable option for mandible reconstruction. The aim of this study was to determine whether CAD/CAM plates provide higher fatigue strength compared with conventional fixation systems. 1.0 mm miniplates, 2.0 mm conventional locking plates (DePuy Synthes, Umkirch, Germany), and 2.0 mm CAD/CAM plates (Materialise, Leuven, Belgium/DePuy Synthes) were used to reconstruct a polyurethane mandible model (Synbone, Malans, CH) with cortical and cancellous bone equivalents. Mastication was simulated via cyclic dynamic testing using a universal testing machine (MTS, Bionix, Eden Prairie, MN, USA) until material failure reached a rate of 1 Hz with increasing loads on the left side. No significant difference was found between the groups until a load of 300 N. At higher loads, vertical displacement differed increasingly, with a poorer performance of miniplates (p = 0.04). Plate breakage occurred in miniplates and conventional locking plates. Screw breakage was recorded as the primary failure mechanism in CAD/CAM plates. Stiffness was significantly higher with the CAD/CAM plates (p = 0.04). CAD/CAM plates and reconstruction plates provide higher fatigue strength than miniplates, and stiffness is highest in CAD/CAM systems. All tested fixation methods seem sufficiently stable for mandible reconstruction. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Comparison of Fit of Dentures Fabricated by Traditional Techniques Versus CAD/CAM Technology.

PubMed

McLaughlin, J Bryan; Ramos, Van; Dickinson, Douglas P

2017-11-14

To compare the shrinkage of denture bases fabricated by three methods: CAD/CAM, compression molding, and injection molding. The effect of arch form and palate depth was also tested. Nine titanium casts, representing combinations of tapered, ovoid, and square arch forms and shallow, medium, and deep palate depths, were fabricated using electron beam melting (EBM) technology. For each base fabrication method, three poly(vinyl siloxane) impressions were made from each cast, 27 dentures for each method. Compression-molded dentures were fabricated using Lucitone 199 poly methyl methacrylate (PMMA), and injection molded dentures with Ivobase's Hybrid Pink PMMA. For CAD/CAM, denture bases were designed and milled by Avadent using their Light PMMA. To quantify the space between the denture and the master cast, silicone duplicating material was placed in the intaglio of the dentures, the titanium master cast was seated under pressure, and the silicone was then trimmed and recovered. Three silicone measurements per denture were recorded, for a total of 243 measurements. Each silicone measurement was weighed and adjusted to the surface area of the respective arch, giving an average and standard deviation for each denture. Comparison of manufacturing methods showed a statistically significant difference (p = 0.0001). Using a ratio of the means, compression molding had on average 41% to 47% more space than injection molding and CAD/CAM. Comparison of arch/palate forms showed a statistically significant difference (p = 0.023), with shallow palate forms having more space with compression molding. The ovoid shallow form showed CAD/CAM and compression molding had more space than injection molding. Overall, injection molding and CAD/CAM fabrication methods produced equally well-fitting dentures, with both having a better fit than compression molding. Shallow palates appear to be more affected by shrinkage than medium or deep palates. Shallow ovoid arch forms appear to benefit from

The Coronary Artery Disease-Reporting and Data System (CAD-RADS): Prognostic and Clinical Implications Associated With Standardized Coronary Computed Tomography Angiography Reporting.

PubMed

Xie, Joe X; Cury, Ricardo C; Leipsic, Jonathon; Crim, Matthew T; Berman, Daniel S; Gransar, Heidi; Budoff, Matthew J; Achenbach, Stephan; Ó Hartaigh, Bríain; Callister, Tracy Q; Marques, Hugo; Rubinshtein, Ronen; Al-Mallah, Mouaz H; Andreini, Daniele; Pontone, Gianluca; Cademartiri, Filippo; Maffei, Erica; Chinnaiyan, Kavitha; Raff, Gilbert; Hadamitzky, Martin; Hausleiter, Joerg; Feuchtner, Gudrun; Dunning, Allison; DeLago, Augustin; Kim, Yong-Jin; Kaufmann, Philipp A; Villines, Todd C; Chow, Benjamin J W; Hindoyan, Niree; Gomez, Millie; Lin, Fay Y; Jones, Erica; Min, James K; Shaw, Leslee J

2018-01-01

This study sought to assess clinical outcomes associated with the novel Coronary Artery Disease-Reporting and Data System (CAD-RADS) scores used to standardize coronary computed tomography angiography (CTA) reporting and their potential utility in guiding post-coronary CTA care. Clinical decision support is a major focus of health care policies aimed at improving guideline-directed care. Recently, CAD-RADS was developed to standardize coronary CTA reporting and includes clinical recommendations to facilitate patient management after coronary CTA. In the multinational CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter) registry, 5,039 patients without known coronary artery disease (CAD) underwent coronary CTA and were stratified by CAD-RADS scores, which rank CAD stenosis severity as 0 (0%), 1 (1% to 24%), 2 (25% to 49%), 3 (50% to 69%), 4A (70% to 99% in 1 to 2 vessels), 4B (70% to 99% in 3 vessels or ≥50% left main), or 5 (100%). Kaplan-Meier and multivariable Cox models were used to estimate all-cause mortality or myocardial infarction (MI). Receiver-operating characteristic (ROC) curves were used to compare CAD-RADS to the Duke CAD Index and traditional CAD classification. Referrals to invasive coronary angiography (ICA) after coronary CTA were also assessed. Cumulative 5-year event-free survival ranged from 95.2% to 69.3% for CAD-RADS 0 to 5 (p < 0.0001). Higher scores were associated with elevations in event risk (hazard ratio: 2.46 to 6.09; p < 0.0001). The ROC curve for prediction of death or MI was 0.7052 for CAD-RADS, which was noninferior to the Duke Index (0.7073; p = 0.893) and traditional CAD classification (0.7095; p = 0.783). ICA rates were 13% for CAD-RADS 0 to 2, 66% for CAD-RADS 3, and 84% for CAD-RADS ≥4A. For CAD-RADS 3, 58% of all catheterizations occurred within the first 30 days of follow-up. In a patient subset with available medication data, 57% of CAD-RADS 3 patients who received 30

Integration of a CAD System Into an MDO Framework

NASA Technical Reports Server (NTRS)

Townsend, J. C.; Samareh, J. A.; Weston, R. P.; Zorumski, W. E.

1998-01-01

NASA Langley has developed a heterogeneous distributed computing environment, called the Framework for Inter-disciplinary Design Optimization, or FIDO. Its purpose has been to demonstrate framework technical feasibility and usefulness for optimizing the preliminary design of complex systems and to provide a working environment for testing optimization schemes. Its initial implementation has been for a simplified model of preliminary design of a high-speed civil transport. Upgrades being considered for the FIDO system include a more complete geometry description, required by high-fidelity aerodynamics and structures codes and based on a commercial Computer Aided Design (CAD) system. This report presents the philosophy behind some of the decisions that have shaped the FIDO system and gives a brief case study of the problems and successes encountered in integrating a CAD system into the FEDO framework.

A citizen science approach to optimising computer aided detection (CAD) in mammography

NASA Astrophysics Data System (ADS)

Ionescu, Georgia V.; Harkness, Elaine F.; Hulleman, Johan; Astley, Susan M.

2018-03-01

Computer aided detection (CAD) systems assist medical experts during image interpretation. In mammography, CAD systems prompt suspicious regions which help medical experts to detect early signs of cancer. This is a challenging task and prompts may appear in regions that are actually normal, whilst genuine cancers may be missed. The effect prompting has on readers performance is not fully known. In order to explore the effects of prompting errors, we have created an online game (Bat Hunt), designed for non-experts, that mirrors mammographic CAD. This allows us to explore a wider parameter space. Users are required to detect bats in images of flocks of birds, with image difficulty matched to the proportions of screening mammograms in different BI-RADS density categories. Twelve prompted conditions were investigated, along with unprompted detection. On average, players achieved a sensitivity of 0.33 for unprompted detection, and sensitivities of 0.75, 0.83, and 0.92 respectively for 70%, 80%, and 90% of targets prompted, regardless of CAD specificity. False prompts distract players from finding unprompted targets if they appear in the same image. Player performance decreases when the number of false prompts increases, and increases proportionally with prompting sensitivity. Median lowest d' was for unprompted condition (1.08) and the highest for sensitivity 90% and 0.5 false prompts per image (d'=4.48).

Incorporation of composite defects from ultrasonic NDE into CAD and FE models

NASA Astrophysics Data System (ADS)

Bingol, Onur Rauf; Schiefelbein, Bryan; Grandin, Robert J.; Holland, Stephen D.; Krishnamurthy, Adarsh

2017-02-01

Fiber-reinforced composites are widely used in aerospace industry due to their combined properties of high strength and low weight. However, owing to their complex structure, it is difficult to assess the impact of manufacturing defects and service damage on their residual life. While, ultrasonic testing (UT) is the preferred NDE method to identify the presence of defects in composites, there are no reasonable ways to model the damage and evaluate the structural integrity of composites. We have developed an automated framework to incorporate flaws and known composite damage automatically into a finite element analysis (FEA) model of composites, ultimately aiding in accessing the residual life of composites and make informed decisions regarding repairs. The framework can be used to generate a layer-by-layer 3D structural CAD model of the composite laminates replicating their manufacturing process. Outlines of structural defects, such as delaminations, are automatically detected from UT of the laminate and are incorporated into the CAD model between the appropriate layers. In addition, the framework allows for direct structural analysis of the resulting 3D CAD models with defects by automatically applying the appropriate boundary conditions. In this paper, we show a working proof-of-concept for the composite model builder with capabilities of incorporating delaminations between laminate layers and automatically preparing the CAD model for structural analysis using a FEA software.

Issues in assessing multi-institutional performance of BI-RADS-based CAD systems

NASA Astrophysics Data System (ADS)

Markey, Mia K.; Lo, Joseph Y.

2005-04-01

The purpose of this study was to investigate factors that impact the generalization of breast cancer computer-aided diagnosis (CAD) systems that utilize the Breast Imaging Reporting and Data System (BI-RADS). Data sets from four institutions were analyzed: Duke University Medical Center, University of Pennsylvania Medical Center, Massachusetts General Hospital, and Wake Forest University. The latter two data sets are subsets of the Digital Database for Screening Mammography. Each data set consisted of descriptions of mammographic lesions according to the BI-RADS lexicon, patient age, and pathology status (benign/malignant). Models were developed to predict pathology status from the BI-RADS descriptors and the patient age. Comparisons between the models built on data from the different institutions were made in terms of empirical (non-parametric) receiver operating characteristic (ROC) curves. Results suggest that BI-RADS-based CAD systems focused on specific classes of lesions may be more generally applicable than models that cover several lesion types. However, better generalization was seen in terms of the area under the ROC curve than in the partial area index (>90% sensitivity). Previous studies have illustrated the challenges in translating a BI-RADS-based CAD system from one institution to another. This study provides new insights into possible approaches to improve the generalization of BI-RADS-based CAD systems.

Survey on the use of CAD-CAM technology by UK and Irish dental technicians.

PubMed

Blackwell, E; Nesbit, M; Petridis, H

2017-05-12

Statement of the problem Digital workflows (CAD/CAM) have been introduced in dentistry during recent years. No published information exists on dental technicians' use and reporting of this technology.Purpose The aim of this cross sectional survey was to identify the extent digital technology has infiltrated the workplace and to investigate the factors affecting the use of CAD-CAM technology by dental laboratory technicians within Ireland and the UK.Materials and methods A web-based questionnaire was composed (Opinio, Object Planet Inc. Oslo, Norway) and distributed to UK and Irish dental technicians. Answers to all questions were anonymous and grouped such that general information was gathered initially, followed by branching of the survey into two sections depending on whether or not the respondent worked with CAD-CAM technology. Results were compiled and statistical analysis (Fisher's Exact test, SPSS, IBM, Armonk, New York, USA) was performed in order to investigate any correlation between various demographic variables and the answers provided.Results The survey was distributed to 760 UK technicians and 77 Irish technicians. The total number of completed surveys was 105, which yielded a total response rate of 14%. Most technicians reported using some form of CAD/CAM aspect in the workflow, and this was more significant for technicians working in large laboratories. Most training received was company-led. Large laboratories were also significantly correlated with less outsourcing of CAD/CAM work and a change in dental material use leading to the increase of zirconia and the decrease of noble alloys. Dental technicians did not report any significant change in working relationships and staffing as a result of CAD/CAM incorporation. High initial investment cost was the most common reason quoted from non-users, along with the lack of such technology in their working environment.

Supercritical Fluid Extraction and Analysis of Tropospheric Aerosol Particles

NASA Astrophysics Data System (ADS)

Hansen, Kristen J.

An integrated sampling and supercritical fluid extraction (SFE) cell has been designed for whole-sample analysis of organic compounds on tropospheric aerosol particles. The low-volume extraction cell has been interfaced with a sampling manifold for aerosol particle collection in the field. After sample collection, the entire SFE cell was coupled to a gas chromatograph; after on-line extraction, the cryogenically -focused sample was separated and the volatile compounds detected with either a mass spectrometer or a flame ionization detector. A 20-minute extraction at 450 atm and 90 ^circC with pure supercritical CO _2 is sufficient for quantitative extraction of most volatile compounds in aerosol particle samples. A comparison between SFE and thermal desorption, the traditional whole-sample technique for analyses of this type, was performed using ambient aerosol particle samples, as well as samples containing known amounts of standard analytes. The results of these studies indicate that SFE of atmospheric aerosol particles provides quantitative measurement of several classes of organic compounds. SFE provides information that is complementary to that gained by the thermal desorption analysis. The results also indicate that SFE with CO _2 can be validated as an alternative to thermal desorption for quantitative recovery of several organic compounds. In 1989, the organic constituents of atmospheric aerosol particles collected at Niwot Ridge, Colorado, along with various physical and meteorological data, were measured during a collaborative field study. Temporal changes in the composition of samples collected during summertime at the rural site were studied. Thermal desorption-GC/FID was used to quantify selected compounds in samples collected during the field study. The statistical analysis of the 1989 Niwot Ridge data set is presented in this work. Principal component analysis was performed on thirty-one variables selected from the data set in order to ascertain

Metabolite profiling reveals a role for atypical cinnamyl alcohol dehydrogenase CAD1 in the synthesis of coniferyl alcohol in tobacco xylem.

PubMed

Damiani, Isabelle; Morreel, Kris; Danoun, Saïda; Goeminne, Geert; Yahiaoui, Nabila; Marque, Christiane; Kopka, Joachim; Messens, Eric; Goffner, Deborah; Boerjan, Wout; Boudet, Alain-Michel; Rochange, Soizic

2005-11-01

In angiosperms, lignin is built from two main monomers, coniferyl and sinapyl alcohol, which are incorporated respectively as G and S units in the polymer. The last step of their synthesis has so far been considered to be performed by a family of dimeric cinnamyl alcohol dehydrogenases (CAD2). However, previous studies on Eucalyptus gunnii xylem showed the presence of an additional, structurally unrelated, monomeric CAD form named CAD1. This form reduces coniferaldehyde to coniferyl alcohol, but is inactive on sinapaldehyde. In this paper, we report the functional characterization of CAD1 in tobacco (Nicotiana tabacum L.). Transgenic tobacco plants with reduced CAD1 expression were obtained through an RNAi strategy. These plants displayed normal growth and development, and detailed biochemical studies were needed to reveal a role for CAD1. Lignin analyses showed that CAD1 down-regulation does not affect Klason lignin content, and has a moderate impact on G unit content of the non-condensed lignin fraction. However, comparative metabolic profiling of the methanol-soluble phenolic fraction from basal xylem revealed significant differences between CAD1 down-regulated and wild-type plants. Eight compounds were less abundant in CAD1 down-regulated lines, five of which were identified as dimers or trimers of monolignols, each containing at least one moiety derived from coniferyl alcohol. In addition, 3-trans-caffeoyl quinic acid accumulated in the transgenic plants. Together, our results support a significant contribution of CAD1 to the synthesis of coniferyl alcohol in planta, along with the previously characterized CAD2 enzymes.

A comparison of marginal fit between press-fabricated and CAD/CAM lithium disilicate crowns.

PubMed

Carlile, Richard S; Owens, Wade H; Greenwood, William J; Guevara, Peter H

2018-01-01

The purpose of this study was to compare the marginal fit of press-fabricated lithium disilicate crowns with that of computer-aided design/computer-aided manufacturing (CAD/CAM) lithium disilicate crowns to determine if the fabrication method has an influence on marginal fit. The marginal fit of 25 pressed and 25 CAD/CAM crowns was measured using the replica technique. The sites measured were the mesial, distal, facial, and lingual margins. A microscope at 10× magnification was used to obtain the measurements. Each site was measured 4 times, and intraclass correlation coefficients were used to assess measurement errors. An unpaired t test was used to evaluate the differences between the 2 groups. Mean marginal gap measurements were greater for CAD/CAM crowns than for pressed crowns at all sites. Only the difference in mean gap at the facial margin was statistically significant (P < 0.001). Press-fabricated lithium disilicate crowns provided a better marginal fit than those fabricated by CAD/CAM, but both fabrication methods provided crowns with a clinically acceptable marginal fit.

Unique CAD/CAM three-quarter crown restoration of a central incisor: a case report.

PubMed

Goldberg, Marvin B; Siegel, Sharon C; Rezakani, Niloufar

2013-07-01

Computer-aided design and computer-aided manufacturing (CAD/CAM) dentistry has been in use for more than 2 decades. Recent improvements in this technology have made CAD/CAM restorations a viable alternative for routine dental care. This technology is being taught in dental schools to prepare students for contemporary dental practice and is particularly useful in unique restorative situations that allow conservation of tooth structure. This case report describes the restoration of a central incisor that was previously restored with an unesthetic three-quarter gold crown. The tooth exhibited recurrent caries and an unaffected labial wall of supported enamel. A CAD/CAM three-quarter crown was planned to conserve tooth structure. After preparation, the tooth was scanned for a CAD/CAM crown in order to fabricate a ceramic restoration, which was then milled and bonded, producing an esthetic result. Typically, in cases of esthetic enhancement, a labial laminate restoration is fabricated, but in this situation, a different approach was necessary to make a design for the lingual surface of an anterior tooth.

Implant-prosthetic rehabilitation of hemimaxillectomy defects with CAD/CAM suprastructures.

PubMed

Mertens, Christian; de San Jose Gonzalez, Jose; Freudlsperger, Christian; Bodem, Jens; Krisam, Johannes; Hoffmann, Jürgen; Engel, Michael

2016-11-01

Patients with hemimaxillectomy defects after tumor surgery can alternatively be rehabilitated with dental obturators or microvascular flaps. When general medical or oncologic conditions do not permit microvascular surgery, dental obturators are the only solution, yet retention for edentulous patients is often poor. The aim of this study was to evaluate whether CAD/CAM suprastructures supported by implants placed in both residual alveolar ridges and contralateral zygomatic bone could enhance obturator stability and improve functional outcomes. Five edentulous patients with class IId hemimaxillectomy defects were included in the study. Implant-retained reconstructions were planned to support cross-arch CAD/CAM milled suprastructures. Patients had to rate their restorations on a 100-mm visual analogue scale before and after treatment. Additional evaluation was performed using the Oral Health Impact Profile (OHIP-EDENT) questionnaire. In the 5 patients, 7 conventional implants were placed in the remaining zygomatic bone and 16 in the remaining contralateral alveolar ridge. After 4 months of submerged healing, CAD/CAM suprastructures were fabricated that connected all respective implants with each other. All of the prosthetic restorations were removable and bar-retained. They all achieved good defect closure and showed significant improvements concerning general satisfaction (p = 0.0343), stability (p < 0.0001), ability to chew (p = 0.0077), esthetics (p = 0.0173) and foreign body sensation (p = 0.0207). According to the OHIP-EDENT questionnaire (p = 0.0036) the improvements were significant. During the observation period of 29.4 months, no mechanical or biological complications occurred. The CAD/CAM suprastructures improved retention in all treated patients without any complications. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Uncertainties of aerosol retrieval from neglecting non-sphericity of dust aerosols

NASA Astrophysics Data System (ADS)

Li, Chi; Xue, Yong; Yang, Leiku; Guang, Jie

2013-04-01

The Mie theory is conventionally applied to calculate aerosol optical properties in satellite remote sensing applications, while dust aerosols cannot be well modeled by the Mie calculation for their non-sphericity. It has been cited in Mishchenko et al. (1995; 1997) that neglecting non-sphericity can severely influence aerosol optical depth (AOD, ?) retrieval in case of dust aerosols because of large difference of phase functions under spherical and non-spherical assumptions, whereas this uncertainty has not been thoroughly studied. This paper aims at a better understanding of uncertainties on AOD retrieval caused by aerosol non-sphericity. A dust aerosol model with known refractive index and size distribution is generated from long-term AERONET observations since 1999 over China. Then aerosol optical properties, such as the extinction, phase function, single scattering albedo (SSA) are calculated respectively in the assumption of spherical and non-spherical aerosols. Mie calculation is carried out for spherical assumption, meanwhile for non-spherical aerosol modeling, we adopt the pre-calculated scattering kernels and software package presented by Dubovik et al. (2002; 2006), which describes dust as a shape mixture of randomly oriented polydisperse spheroids. Consequently we generate two lookup tables (LUTspheric and LUTspheroid) from simulated satellite received reflectance at top of atmosphere (TOA) under varieties of observing conditions and aerosol loadings using Second Simulation of a Satellite Signal in the Solar Spectrum - Vector (6SV) code. All the simulations are made at 550 nm, and for simplicity the Lambertian surface is assumed. Using the obtained LUTs we examine the differences of TOA reflectance (Δ?TOA = ?spheric - ?spheroid) under different surface reflectance and aerosol loadings. Afterwards AOD is retrieved using LUTspheric from the simulated TOA reflectance by LUTspheroid in order to detect the retrieval errors (Δ? = ?retreived -?input) induced

Overview of NASA MSFC IEC Multi-CAD Collaboration Capability

NASA Technical Reports Server (NTRS)

Moushon, Brian; McDuffee, Patrick

2005-01-01

This viewgraph presentation provides an overview of a Design and Data Management System (DDMS) for Computer Aided Design (CAD) collaboration in order to support the Integrated Engineering Capability (IEC) at Marshall Space Flight Center (MSFC).

An aerosol climatology for a rapidly growing arid region (southern Arizona): Major aerosol species and remotely sensed aerosol properties

NASA Astrophysics Data System (ADS)

Sorooshian, Armin; Wonaschütz, Anna; Jarjour, Elias G.; Hashimoto, Bryce I.; Schichtel, Bret A.; Betterton, Eric A.

2011-10-01

This study reports a comprehensive characterization of atmospheric aerosol particle properties in relation to meteorological and back trajectory data in the southern Arizona region, which includes two of the fastest growing metropolitan areas in the United States (Phoenix and Tucson). Multiple data sets (MODIS, AERONET, OMI/TOMS, MISR, GOCART, ground-based aerosol measurements) are used to examine monthly trends in aerosol composition, aerosol optical depth (AOD), and aerosol size. Fine soil, sulfate, and organics dominate PM2.5 mass in the region. Dust strongly influences the region between March and July owing to the dry and hot meteorological conditions and back trajectory patterns. Because monsoon precipitation begins typically in July, dust levels decrease, while AOD, sulfate, and organic aerosol reach their maximum levels because of summertime photochemistry and monsoon moisture. Evidence points to biogenic volatile organic compounds being a significant source of secondary organic aerosol in this region. Biomass burning also is shown to be a major contributor to the carbonaceous aerosol budget in the region, leading to enhanced organic and elemental carbon levels aloft at a sky-island site north of Tucson (Mt. Lemmon). Phoenix exhibits different monthly trends for aerosol components in comparison with the other sites owing to the strong influence of fossil carbon and anthropogenic dust. Trend analyses between 1988 and 2009 indicate that the strongest statistically significant trends are reductions in sulfate, elemental carbon, and organic carbon, and increases in fine soil during the spring (March-May) at select sites. These results can be explained by population growth, land-use changes, and improved source controls.

Detection of chemical agent aerosols

NASA Astrophysics Data System (ADS)

Fox, Jay A.; Ahl, Jeffrey L.; D'Amico, Francis M.; Vanderbeek, Richard G.; Moon, Raphael; Swim, Cynthia R.

1999-05-01

One of the major threats presented by a chemical agent attack is that of a munition exploding overhead and 'raining' aerosols which can contaminate surfaces when they impact. Since contact with these surfaces can be fatal, it is imperative to know when such an attack has taken place and the likely threat density and location. We present the results of an experiment designed to show the utility of a CO2 lidar in detecting such an attack. Testing occurred at Dugway Proving Grounds, Utah and involved the simulation of an explosive airburst chemical attack. Explosions occurred at a height of 30 m and liquid droplets from two chemicals, PEG-200 (polyethylene glycol 200) and TEP (triethylphosphate), were expelled and fell to the ground. The munition was the U.S. Army M9 Simulator, Projectile, Airburst, Liquid (SPAL) system that is designed for chemical warfare training exercises. The instrument that was used to detect the presence of the aerosols was the Laser Standoff Chemical Detector (LSCD) which is a light detection and ranging (LIDAR) system that utilizes a rapidly tunable, pulsed CO2 laser. The LIDAR scanned a horizontal path approximately 5 - 8 m above the ground in order to measure the concentration of liquid deposition. The LIDAR data were later correlated with card data to determine how well the system could predict the location and quantity of liquid deposition on the ground.

The design and integration of retinal CAD-SR to diabetes patient ePR system

NASA Astrophysics Data System (ADS)

Wu, Huiqun; Wei, Yufang; Liu, Brent J.; Shang, Yujuan; Shi, Lili; Jiang, Kui; Dong, Jiancheng

2017-03-01

Diabetic retinopathy (DR) is one of the serious complications of diabetes that could lead to blindness. Digital fundus camera is often used to detect retinal changes but the diagnosis relies too much on ophthalmologist's experience. Based on our previously developed algorithms for quantifying retinal vessels and lesions, we developed a computer aided detection-structured report (CAD-SR) template and implemented it into picture archiving and communication system (PACS). Furthermore, we mapped our CAD-SR into HL7 CDA to integrate CAD findings into diabetes patient electronic patient record (ePR) system. Such integration could provide more quantitative features from fundus image into ePR system, which is valuable for further data mining researches.

Dental biomaterials for chairside CAD/CAM: State of the art

PubMed Central

2017-01-01

The wide use of chairside CAD/CAM restorations has increased the diversity of the restorative material. For the practitioner, the selection of the appropriate material is difficult amongst the variety offered by the market. Information on the characteristics of the products can be difficult to assess due to the lack of up-to-date classification and the lack of reliability of manufacturer's advertising. The purpose of this article is to structure the data on restorative materials provided by various sources in order for the practitioner to choose the product most suited to the clinical situation. The objective is to classify chairside CAD/CAM materials and to define their characteristics and indications. PMID:29279770

From Oss CAD to Bim for Cultural Heritage Digital Representation

NASA Astrophysics Data System (ADS)

Logothetis, S.; Karachaliou, E.; Stylianidis, E.

2017-02-01

The paper illustrates the use of open source Computer-aided design (CAD) environments in order to develop Building Information Modelling (BIM) tools able to manage 3D models in the field of cultural heritage. Nowadays, the development of Free and Open Source Software (FOSS) has been rapidly growing and their use tends to be consolidated. Although BIM technology is widely known and used, there is a lack of integrated open source platforms able to support all stages of Historic Building Information Modelling (HBIM) processes. The present research aims to use a FOSS CAD environment in order to develop BIM plug-ins which will be able to import and edit digital representations of cultural heritage models derived by photogrammetric methods.

Circulating irisin levels are lower in patients with either stable coronary artery disease (CAD) or myocardial infarction (MI) versus healthy controls, whereas follistatin and activin A levels are higher and can discriminate MI from CAD with similar to CK-MB accuracy.

PubMed

Anastasilakis, Athanasios D; Koulaxis, Dimitrios; Kefala, Nikoleta; Polyzos, Stergios A; Upadhyay, Jagriti; Pagkalidou, Eirini; Economou, Fotios; Anastasilakis, Chrysostomos D; Mantzoros, Christos S

2017-08-01

Several myokines are produced by cardiac muscle. We investigated changes in myokine levels at the time of acute myocardial infarction (MI) and following reperfusion in relation to controls. Patients with MI (MI Group, n=31) treated with percutaneous coronary intervention (PCI) were compared to patients with stable coronary artery disease (CAD) subjected to scheduled PCI (CAD Group, n=40) and controls with symptoms mimicking CAD without stenosis in angiography (Control Group, n=43). The number and degree of stenosis were recorded. Irisin, follistatin, follistatin-like 3, activin A and B, ALT, AST, CK and CK-MB were measured at baseline and 6 or 24h after the intervention. MI and CAD patients had lower irisin than controls (p<0.001). MI patients had higher follistatin, activin A, CK, CK-MB and AST than CAD patients and controls (all p≤0.001). None of the myokines changed following reperfusion. Circulating irisin was associated with the degree of stenosis in all patients (p=0.05). Irisin was not inferior to CK-MB in predicting MI while folistatin and activin A could discriminate MI from CAD patients with similar to CK-MB accuracy. None of these myokines was altered following PCI in contrast to CK-MB. Irisin levels are lower in MI and CAD implying that their production may depend on myocadial blood supply. Follistatin and activin A are higher in MI than in CAD suggesting increased release due to myocardial necrosis. They can predict MI with accuracy similar to CK-MB and their role in the diagnosis of MI remains to be confirmed by prospective large clinical studies. Copyright © 2017 Elsevier Inc. All rights reserved.

Aerosols and lightning activity: The effect of vertical profile and aerosol type

NASA Astrophysics Data System (ADS)

Proestakis, E.; Kazadzis, S.; Lagouvardos, K.; Kotroni, V.; Amiridis, V.; Marinou, E.; Price, C.; Kazantzidis, A.

2016-12-01

The Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) instrument on board the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) satellite has been utilized for the first time in a study regarding lightning activity modulation due to aerosols. Lightning activity observations, obtained by the ZEUS long range Lightning Detection Network, European Centre for Medium range Weather Forecasts (ECMWF) Convective Available Potential Energy (CAPE) data and Cloud Fraction (CF) retrieved by MODIS on board Aqua satellite have been combined with CALIPSO CALIOP data over the Mediterranean basin and for the period March to November, from 2007 to 2014. The results indicate that lightning activity is enhanced during days characterized by higher Aerosol Optical Depth (AOD) values, compared to days with no lightning. This study contributes to existing studies on the link between lightning activity and aerosols, which have been based just on columnar AOD satellite retrievals, by performing a deeper analysis into the effect of aerosol profiles and aerosol types. Correlation coefficients of R = 0.73 between the CALIPSO AOD and the number of lightning strikes detected by ZEUS and of R = 0.93 between ECMWF CAPE and lightning activity are obtained. The analysis of extinction coefficient values at 532 nm indicates that at an altitudinal range exists, between 1.1 km and 2.9 km, where the values for extinction coefficient of lightning-active and non-lightning-active cases are statistically significantly different. Finally, based on the CALIPSO aerosol subtype classification, we have investigated the aerosol conditions of lightning-active and non-lightning-active cases. According to the results polluted dust aerosols are more frequently observed during non-lightning-active days, while dust and smoke aerosols are more abundant in the atmosphere during the lightning-active days.

Aerosol climatology: on the discrimination of aerosol types over four AERONET sites

NASA Astrophysics Data System (ADS)

Kaskaoutis, D. G.; Kambezidis, H. D.; Hatzianastassiou, N.; Kosmopoulos, P. G.; Badarinath, K. V. S.

2007-05-01

Aerosols have a significant regional and global effect on climate, which is about equal in magnitude but opposite in sign to that of greenhouse gases. Nevertheless, the aerosol climatic effect changes strongly with space and time because of the large variability of aerosol physical and optical properties, which is due to the variety of their sources, which are natural, and anthropogenic, and their dependence on the prevailing meteorological and atmospheric conditions. Characterization of aerosol properties is of major importance for the assessment of their role for climate. In the present study, 3-year AErosol RObotic NETwork (AERONET) data from ground-based sunphotometer measurements are used to establish climatologies of aerosol optical depth (AOD) and Ångström exponent α in several key locations of the world, characteristic of different atmospheric environments. Using daily mean values of AOD at 500 nm (AOD500) and Ångström exponent at the pair of wavelengths 440 and 870 nm (α 440-870), a discrimination of the different aerosol types occurring in each location is achieved. For this discrimination, appropriate thresholds for AOD500 and α 440-870 are applied. The discrimination of aerosol types in each location is made on an annual and seasonal basis. It is shown that a single aerosol type in a given location can exist only under specific conditions (e.g. intense forest fires or dust outbreaks), while the presence of well-mixed aerosols is the accustomed situation. Background clean aerosol conditions (AOD500<0.06) are mostly found over remote oceanic surfaces occurring on average in ~56.7% of total cases, while this situation is quite rare over land (occurrence of 3.8-13.7%). Our analysis indicates that these percentages change significantly from season to season. The spectral dependence of AOD exhibits large differences between the examined locations, while it exhibits a strong annual cycle.

Aerosol retrieval experiments in the ESA Aerosol_cci project

NASA Astrophysics Data System (ADS)

Holzer-Popp, T.; de Leeuw, G.; Griesfeller, J.; Martynenko, D.; Klüser, L.; Bevan, S.; Davies, W.; Ducos, F.; Deuzé, J. L.; Graigner, R. G.; Heckel, A.; von Hoyningen-Hüne, W.; Kolmonen, P.; Litvinov, P.; North, P.; Poulsen, C. A.; Ramon, D.; Siddans, R.; Sogacheva, L.; Tanre, D.; Thomas, G. E.; Vountas, M.; Descloitres, J.; Griesfeller, J.; Kinne, S.; Schulz, M.; Pinnock, S.

2013-08-01

Within the ESA Climate Change Initiative (CCI) project Aerosol_cci (2010-2013), algorithms for the production of long-term total column aerosol optical depth (AOD) datasets from European Earth Observation sensors are developed. Starting with eight existing pre-cursor algorithms three analysis steps are conducted to improve and qualify the algorithms: (1) a series of experiments applied to one month of global data to understand several major sensitivities to assumptions needed due to the ill-posed nature of the underlying inversion problem, (2) a round robin exercise of "best" versions of each of these algorithms (defined using the step 1 outcome) applied to four months of global data to identify mature algorithms, and (3) a comprehensive validation exercise applied to one complete year of global data produced by the algorithms selected as mature based on the round robin exercise. The algorithms tested included four using AATSR, three using MERIS and one using PARASOL. This paper summarizes the first step. Three experiments were conducted to assess the potential impact of major assumptions in the various aerosol retrieval algorithms. In the first experiment a common set of four aerosol components was used to provide all algorithms with the same assumptions. The second experiment introduced an aerosol property climatology, derived from a combination of model and sun photometer observations, as a priori information in the retrievals on the occurrence of the common aerosol components. The third experiment assessed the impact of using a common nadir cloud mask for AATSR and MERIS algorithms in order to characterize the sensitivity to remaining cloud contamination in the retrievals against the baseline dataset versions. The impact of the algorithm changes was assessed for one month (September 2008) of data: qualitatively by inspection of monthly mean AOD maps and quantitatively by comparing daily gridded satellite data against daily averaged AERONET sun photometer

Adherence of Candida to complete denture surfaces in vitro: A comparison of conventional and CAD/CAM complete dentures

PubMed Central

Al-mejrad, Lamya A.; Albarrag, Ahmed M.

2017-01-01

PURPOSE The goal of this study was to compare the adhesion of Candida albicans to the surfaces of CAD/CAM and conventionally fabricated complete denture bases. MATERIALS AND METHODS Twenty discs of acrylic resin poly (methyl methacrylate) were fabricated with CAD/CAM and conventional procedures (heat-polymerized acrylic resin). The specimens were divided into two groups: 10 discs were fabricated using the CAD/CAM procedure (Wieland Digital Denture Ivoclar Vivadent), and 10 discs were fabricated using a conventional flasking and pressure-pack technique. Candida colonization was performed on all the specimens using four Candida albicans isolates. The difference in Candida albicans adhesion on the discs was evaluated. The number of adherent yeast cells was calculated by the colony-forming units (CFU) and by Fluorescence microscopy. RESULTS There was a significant difference in the adhesion of Candida albicans to the complete denture bases created with CAD/CAM and the adhesion to those created with the conventional procedure. The CAD/CAM denture bases exhibited less adhesion of Candida albicans than did the denture bases created with the conventional procedure (P<.05). CONCLUSION The CAD/CAM procedure for fabricating complete dentures showed promising potential for reducing the adherence of Candida to the denture base surface. Clinical Implications. Complete dentures made with the CAD/CAM procedure might decrease the incidence of denture stomatitis compared with conventional dentures. PMID:29142649

Adherence of Candida to complete denture surfaces in vitro: A comparison of conventional and CAD/CAM complete dentures.

PubMed

Al-Fouzan, Afnan F; Al-Mejrad, Lamya A; Albarrag, Ahmed M

2017-10-01

The goal of this study was to compare the adhesion of Candida albicans to the surfaces of CAD/CAM and conventionally fabricated complete denture bases. Twenty discs of acrylic resin poly (methyl methacrylate) were fabricated with CAD/CAM and conventional procedures (heat-polymerized acrylic resin). The specimens were divided into two groups: 10 discs were fabricated using the CAD/CAM procedure (Wieland Digital Denture Ivoclar Vivadent), and 10 discs were fabricated using a conventional flasking and pressure-pack technique. Candida colonization was performed on all the specimens using four Candida albicans isolates. The difference in Candida albicans adhesion on the discs was evaluated. The number of adherent yeast cells was calculated by the colony-forming units (CFU) and by Fluorescence microscopy. There was a significant difference in the adhesion of Candida albicans to the complete denture bases created with CAD/CAM and the adhesion to those created with the conventional procedure. The CAD/CAM denture bases exhibited less adhesion of Candida albicans than did the denture bases created with the conventional procedure ( P <.05). The CAD/CAM procedure for fabricating complete dentures showed promising potential for reducing the adherence of Candida to the denture base surface. Clinical Implications. Complete dentures made with the CAD/CAM procedure might decrease the incidence of denture stomatitis compared with conventional dentures.

The Two-Column Aerosol Project: Phase I - Overview and Impact of Elevated Aerosol Layers on Aerosol Optical Depth

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

Berg, Larry K.; Fast, Jerome D.; Barnard, James C.

2016-01-08

The Two-Column Aerosol Project (TCAP), which was conducted from June 2012 through June 2013, was a unique field study that was designed to provide a comprehensive data set that can be used to investigate a number of important climate science questions, including those related to aerosol mixing state and aerosol radiative forcing. The study was designed to sample the atmosphere at a number of altitudes, from near the surface to as high as 8 km, within two atmospheric columns; one located near the coast of North America (over Cape Cod, MA) and a second over the Atlantic Ocean several hundredmore » kilometers from the coast. TCAP included the yearlong deployment of the U.S. Department of Energy’s (DOE) Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF) that was located at the base of the Cape Cod column, as well as summer and winter aircraft intensive observation periods of the ARM Aerial Facility. One important finding from TCAP is the relatively common occurrence (on four of six nearly cloud-free flights) of elevated aerosol layers in both the Cape Cod and maritime columns that were detected using the nadir pointing second-generation NASA high-spectral resolution lidar (HSRL-2). These layers contributed up to 60% of the total aerosol optical depth (AOD) observed in the column. Many of these layers were also intercepted by the aircraft configured for in situ sampling, and the aerosol in the layers was found to have increased amounts of biomass burning aerosol and nitrate compared to the aerosol found near the surface.« less

The Two-Column Aerosol Project: Phase I-Overview and impact of elevated aerosol layers on aerosol optical depth

DOE PAGES

Berg, Larry K.; Fast, Jerome D.; Barnard, James C.; ...

2016-01-08

The Two-Column Aerosol Project (TCAP), conducted from June 2012 through June 2013, was a unique study designed to provide a comprehensive data set that can be used to investigate a number of important climate science questions, including those related to aerosol mixing state and aerosol radiative forcing. The study was designed to sample the atmosphere between and within two atmospheric columns; one fixed near the coast of North America (over Cape Cod, MA) and a second moveable column over the Atlantic Ocean several hundred kilometers from the coast. The U.S. Department of Energy's (DOE) Atmospheric Radiation Measurement (ARM) Mobile Facilitymore » (AMF) was deployed at the base of the Cape Cod column, and the ARM Aerial Facility was utilized for the summer and winter intensive observation periods. One important finding from TCAP is that four of six nearly cloud-free flight days had aerosol layers aloft in both the Cape Cod and maritime columns that were detected using the nadir pointing second-generation NASA high-spectral resolution lidar (HSRL-2). In addition, these layers contributed up to 60% of the total observed aerosol optical depth (AOD). Many of these layers were also intercepted by the aircraft configured for in situ sampling, and the aerosol in the layers was found to have increased amounts of biomass burning material and nitrate compared to aerosol found near the surface. Lastly, while there was a great deal of spatial and day-to-day variability in the aerosol chemical composition and optical properties, no systematic differences between the two columns were observed.« less

The Two-Column Aerosol Project: Phase I - Overview and Impact of Elevated Aerosol Layers on Aerosol Optical Depth

NASA Technical Reports Server (NTRS)

Berg, Larry K.; Fast, Jerome D.; Barnard, James C.; Burton, Sharon P.; Cairns, Brian; Chand, Duli; Comstock, Jennifer M.; Dunagan, Stephen; Ferrare, Richard A.; Flynn, Connor J.;

The Two-Column Aerosol Project: Phase I—Overview and impact of elevated aerosol layers on aerosol optical depth

NASA Astrophysics Data System (ADS)

Berg, Larry K.; Fast, Jerome D.; Barnard, James C.; Burton, Sharon P.; Cairns, Brian; Chand, Duli; Comstock, Jennifer M.; Dunagan, Stephen; Ferrare, Richard A.; Flynn, Connor J.; Hair, Johnathan W.; Hostetler, Chris A.; Hubbe, John; Jefferson, Anne; Johnson, Roy; Kassianov, Evgueni I.; Kluzek, Celine D.; Kollias, Pavlos; Lamer, Katia; Lantz, Kathleen; Mei, Fan; Miller, Mark A.; Michalsky, Joseph; Ortega, Ivan; Pekour, Mikhail; Rogers, Ray R.; Russell, Philip B.; Redemann, Jens; Sedlacek, Arthur J.; Segal-Rosenheimer, Michal; Schmid, Beat; Shilling, John E.; Shinozuka, Yohei; Springston, Stephen R.; Tomlinson, Jason M.; Tyrrell, Megan; Wilson, Jacqueline M.; Volkamer, Rainer; Zelenyuk, Alla; Berkowitz, Carl M.

2016-01-01

The Two-Column Aerosol Project (TCAP), conducted from June 2012 through June 2013, was a unique study designed to provide a comprehensive data set that can be used to investigate a number of important climate science questions, including those related to aerosol mixing state and aerosol radiative forcing. The study was designed to sample the atmosphere between and within two atmospheric columns; one fixed near the coast of North America (over Cape Cod, MA) and a second moveable column over the Atlantic Ocean several hundred kilometers from the coast. The U.S. Department of Energy's (DOE) Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF) was deployed at the base of the Cape Cod column, and the ARM Aerial Facility was utilized for the summer and winter intensive observation periods. One important finding from TCAP is that four of six nearly cloud-free flight days had aerosol layers aloft in both the Cape Cod and maritime columns that were detected using the nadir pointing second-generation NASA high-spectral resolution lidar (HSRL-2). These layers contributed up to 60% of the total observed aerosol optical depth (AOD). Many of these layers were also intercepted by the aircraft configured for in situ sampling, and the aerosol in the layers was found to have increased amounts of biomass burning material and nitrate compared to aerosol found near the surface. In addition, while there was a great deal of spatial and day-to-day variability in the aerosol chemical composition and optical properties, no systematic differences between the two columns were observed.

Aerosol polarization effects on atmospheric correction and aerosol retrievals in ocean color remote sensing.

PubMed

Wang, Menghua

2006-12-10

The current ocean color data processing system for the Sea-viewing Wide Field-of-View Sensor (SeaWiFS) and the moderate resolution imaging spectroradiometer (MODIS) uses the Rayleigh lookup tables that were generated using the vector radiative transfer theory with inclusion of the polarization effects. The polarization effects, however, are not accounted for in the aerosol lookup tables for the ocean color data processing. I describe a study of the aerosol polarization effects on the atmospheric correction and aerosol retrieval algorithms in the ocean color remote sensing. Using an efficient method for the multiple vector radiative transfer computations, aerosol lookup tables that include polarization effects are generated. Simulations have been carried out to evaluate the aerosol polarization effects on the derived ocean color and aerosol products for all possible solar-sensor geometries and the various aerosol optical properties. Furthermore, the new aerosol lookup tables have been implemented in the SeaWiFS data processing system and extensively tested and evaluated with SeaWiFS regional and global measurements. Results show that in open oceans (maritime environment), the aerosol polarization effects on the ocean color and aerosol products are usually negligible, while there are some noticeable effects on the derived products in the coastal regions with nonmaritime aerosols.

Influence of different surface treatments on bond strength of novel CAD/CAM restorative materials to resin cement

PubMed Central

Kömürcüoğlu, Meltem Bektaş; Sağırkaya, Elçin

2017-01-01

PURPOSE To evaluate the effects of different surface treatments on the bond strength of novel CAD/CAM restorative materials to resin cement by four point bending test. MATERIALS AND METHODS The CAD/CAM materials under investigation were e.max CAD, Mark II, Lava Ultimate, and Enamic. A total of 400 bar specimens (4×1.2×12 mm) (n=10) milled from the CAD/CAM blocks underwent various pretreatments (no pretreatment (C), hydrofluoric acid (A), hydrofluoric acid + universal adhesive (Scotchbond) (AS), sandblasting (Sb), and sandblasting + universal adhesive (SbS)). The bars were luted end-to-end on the prepared surfaces with a dual curing adhesive resin cement (Variolink N, Ivoclar Vivadent) on the custom-made stainless steel mold. Ten test specimens for each treatment and material combination were performed with four point bending test method. Data were analyzed using ANOVA and Tukey's test. RESULTS The surface treatment and type of CAD/CAM restorative material showed a significant effect on the four point bending strength (FPBS) (P<.001). For LDC, AS surface treatment showed the highest FPBS results (100.31 ± 10.7 MPa) and the lowest values were obtained in RNC (23.63 ± 9.0 MPa) for control group. SEM analyses showed that the surface topography of CAD/CAM restorative materials was modified after treatments. CONCLUSION The surface treatment of sandblasting or HF acid etching in combination with a universal adhesive containing MDP can be suggested for the adhesive cementation of the novel CAD/CAM restorative materials. PMID:29279763

TNF-alpha-308G>A polymorphism and the risk of familial CAD in a Pakistani population.

PubMed

Hussain, Sabir; Iqbal, Tahir; Javed, Qamar

2015-01-01

A case-control and trio-families study was performed to establish a potential association between TNF-alpha gene promoter SNPs at -308 and -238, and occurrence of CAD in a Pakistani population. In the first phase, 150 patients and 150 controls were enrolled in the case-control association study. In the second phase, heritability of susceptible alleles was investigated from 88 trio-families with CAD affected offspring. Biochemical analysis of lipids and hs-CRP was carried out spectrophotometrically, while serum TNF-alpha concentrations were determined by enzyme-linked immunosorbent assay. Genotyping of the TNF-alpha SNPs were determined by PCR-RFLP method. Elevated serum TNF-alpha and hs-CRP were observed from CAD vs. controls (P<0.0001; for both). The evaluation of TNF-alpha-308G>A polymorphism in case-control study revealed that the said SNP was significantly associated with the increased risk of CAD. The findings demonstrated a significant link between the TNF-alpha variant allele A at -308 and CAD (P=0.0035), whereas the -238 SNP was not associated with the disease. Haplotype A-G of the TNF-alpha gene at -308G>A and -238G>A showed higher frequency in the patient group compared with controls (P<0.05). Moreover, data showed preferential transmission of the disease susceptible allele A at TNF-alpha-308 from parent to affected offspring in a trio-family study (P<0.0001). The current research leads to conclusion that the TNF-alpha-308G>A polymorphism is associated with CAD in the study population. Furthermore, for the first time, we showed that the TNF-alpha-308A allele was significantly associated with the familial CAD in our high risk population. Copyright © 2014. Published by Elsevier Inc.

JAMSTEC Compact Arctic Drifter (J-CAD): A new Generation drifting buoy to observe the Arctic Ocean

NASA Astrophysics Data System (ADS)

Hatakeyama, Kiyoshi; Hosono, Masuo; Shimada, Koji; Kikuchi, Takashi; Nishino, Shigeto

The Arctic Ocean is one of the most sensitive regions to the earth environment changes. Japan Marine Science and Technology Center developed a new drift buoy to observe the Arctic Ocean. The name of the buoy is J-CAD (JAMSTEC Compact Arctic Drifter). From 1991 to 1993, JAMSTEC developed Ice-Ocean Environmental Buoy (IOEB) as a buoy to observe the Arctic Ocean in cooperation with Woods Hole Oceanographic Institution. The J-CAD is the buoy, which adopted the latest technology based on the knowledge and experience of IOEB development. The J-CAD was designed and developed by JAMSTEC and made by a Canadian Company MetOcean. JAMSTEC did design and development, and a Canadian company Met-Ocean made the J-CAD. It acquires meteorological and oceanographic data of the Arctic Ocean, and transmits the data that it measured via satellite. It dose also store the data inside its memory. An Inductive Modem system, which was developed by Sea-Bird Electronics, Inc. in the United States, was adopted in the underwater transmission system that data on each ocean sensor were collected. An ORBCOMM communication system was adopted for the satellite data transmission. J-CAD-1 was installed at 89°41'N 130°20'W on April 24, 2000, and the observation was started. August 1st was the day when 100 days have passed since the J-CAD-1 was installed on the North Pole. And now, the distance J-CAD-1 has covered exceeds 400 km, and it has transmitted data more than 500 k byte. A part of the data is introduced to the public in the homepage (http://w3.jamstec.go.jp: 8338) of the Arctic research group of JAMSTEC.

The effect of organic aerosol material on aerosol reactivity towards ozone

NASA Astrophysics Data System (ADS)

Batenburg, Anneke; Gaston, Cassandra; Thornton, Joel; Virtanen, Annele

2015-04-01

After aerosol particles are formed or emitted into the atmosphere, heterogeneous reactions with gaseous oxidants cause them to 'age'. Aging can change aerosol properties, such as the hygroscopicity, which is an important parameter in how the particles scatter radiation and form clouds. Conversely, heterogeneous reactions on aerosol particles play a significant role in the cycles of various atmospheric trace gases. Organic compounds, a large part of the total global aerosol matter, can exist in liquid or amorphous (semi)solid physical phases. Different groups have shown that reactions with ozone (O3) can be limited by bulk diffusion in organic aerosol, particularly in viscous, (semi)solid materials, and that organic coatings alter the surface interactions between gas and aerosol particles. We aim to better understand and quantify how the viscosity and phase of organic aerosol matter affect gas-particle interactions. We have chosen the reaction of O3 with particles composed of a potassium iodide (KI) core and a variable organic coating as a model system. The reaction is studied in an aerosol flow reactor that consists of a laminar flow tube and a movable, axial injector for the injection of O3. The aerosol-containing air is inserted at the tube's top. The interaction length (and therefore time), between the particles and the O3 can be varied by moving the injector. Alternatively, the production of aerosol particles can be modulated. The remaining O3 concentration is monitored from the bottom of the tube and particle concentrations are measured simultaneously, which allows us to calculate the reactive uptake coefficient γ. We performed exploratory experiments with internally mixed KI and polyethylene glycol (PEG) particles at the University of Washington (UW) in a setup with a residence time around 50 s. Aerosol particles were generated in an atomizer from solutions with varying concentrations of KI and PEG and inserted into the flow tube after they were diluted and

Flexural strength and reliability of monolithic and trilayer ceramic structures obtained by the CAD-on technique.

PubMed

Basso, G R; Moraes, R R; Borba, M; Griggs, J A; Della Bona, A

2015-12-01

To evaluate the flexural strength, Weibull modulus, fracture toughness, and failure behavior of ceramic structures obtained by the CAD-on technique, testing the null hypothesis that trilayer structures show similar properties to monolithic structures. Bar-shaped (1.8mm×4mm×16mm) monolithic specimens of zirconia (IPS e.max ZirCAD - Ivoclar Vivadent) and trilayer specimens of zirconia/fusion ceramic/lithium dissilicate (IPS e.max ZirCAD/IPS e.max CAD Crystall./Connect/IPS e.max CAD, Ivoclar Vivadent) were fabricated (n=30). Specimens were tested in flexure in 37°C deionized water using a universal testing machine at a crosshead speed of 0.5mm/min. Failure loads were recorded, and the flexural strength values were calculated. Fractography principles were used to examine the fracture surfaces under optical and scanning electron microscopy. Data were statistically analyzed using Student's t-test and Weibull statistics (α=0.05). Monolithic and trilayer specimens showed similar mean flexural strengths, characteristic strengths, and Weibull moduli. Trilayer structures showed greater mean critical flaw and fracture toughness values than monolithic specimens (p<0.001). Most critical flaws in the trilayer groups were located on the Y-TZP surface subjected to tension and propagated catastrophically. Trilayer structures showed no flaw deflection at the interface. Considering the CAD-on technique, the trilayer structures showed greater fracture toughness than the monolithic zirconia specimens. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Development of a Bioaerosol single particle detector (BIO IN) for the Fast Ice Nucleus CHamber FINCH

NASA Astrophysics Data System (ADS)

Bundke, U.; Reimann, B.; Nillius, B.; Jaenicke, R.; Bingemer, H.

2010-02-01

In this work we present the setup and first tests of our new BIO IN detector. This detector was constructed to classify atmospheric ice nuclei (IN) for their biological content. It is designed to be coupled to the Fast Ice Nucleus CHamber FINCH. If one particle acts as an ice nucleus, it will be at least partly covered with ice at the end of the development section of the FINCH chamber. The device combines an auto-fluorescence detector and a circular depolarization detector for simultaneous detection of biological material and discrimination between water droplets, ice crystals and non activated large aerosol particles. The excitation of biological material with UV light and analysis of auto-fluorescence is a common principle used for flow cytometry, fluorescence microscopy, spectroscopy and imaging. The detection of auto-fluorescence of airborne single particles demands some more experimental effort. However, expensive commercial sensors are available for special purposes, e.g. size distribution measurements. But these sensors will not fit the specifications needed for the FINCH IN counter (e.g. high sample flow of up 10 LPM). The newly developed -low cost- BIO IN sensor uses a single high-power UV LED for the electronic excitation instead of much more expensive UV lasers. Other key advantages of the new sensor are the low weight, compact size, and the little effect on the aerosol sample, which allows it to be coupled with other instruments for further analysis. The instrument will be flown on one of the first missions of the new German research aircraft "HALO" (High Altitude and LOng range).

Clinical Evaluation of Indirect Particle-Filled Composite Resin CAD/CAM Partial Crowns after 24 Months.

PubMed

Zimmermann, Moritz; Koller, Christina; Reymus, Marcel; Mehl, Albert; Hickel, Reinhard

2017-04-19

Resin-based CAD/CAM compound materials might be promising for single-tooth restorations. Insufficient clinical data are available for this new material class. The purpose of this study was to describe initial clinical in vivo results for indirect particle-filled composite resin CAD/CAM restorations after 24 months. Indirect particle-filled composite resin restorations were fabricated with a CAD/CAM method (CEREC Bluecam intraoral scanner, CEREC MCXL milling unit) by calibrated dental students. Forty-two partial crown restorations were seated adhesively in 30 patients with caries lesions or insufficient restorations (baseline). Strict inclusion criteria were defined for the patient collective. Follow-up evaluation comprised 40 restorations after 12 months and 33 restorations after 24 months. Evaluation criteria were modified FDI criteria with grades (1) to (5). Rating with FDI criteria (5) was defined as clinical failure. Statistical analysis was performed with Wilcoxon-Test (p < 0.05). The success rate of indirect particle-filled composite resin CAD/CAM restorations after 12 months was 95.0% with two debondings observed. The cumulative success rate for indirect particle-filled composite resin CAD/CAM restorations after 24 months was 85.7% with two tooth fractures and one debonding. Statistically significant differences were found for baseline and 24-month follow-up evaluation for anatomic form and marginal adaptation criterion examined in respect to FDI criteria guidelines (Wilcoxon-Test, p < 0.05). This study demonstrates particle-filled composite resin CAD/CAM restorations having a clinical success rate of 85.7% after 24 months. Adhesive bonding procedures need to be ensured carefully. A longer clinical evaluation period is necessary to draw further conclusions. © 2017 by the American College of Prosthodontists.

Job expansion : an additional benefit of a computer aided dispatch/automatic vehicle locator (CAD/AVL) system

DOT National Transportation Integrated Search

2000-03-01

The Denver Regional Transportation District (RTD) acquired a CAD/AVL system that became fully operational in 1996. The CAD/AVL system added radio channels and covert alarms in buses, located vehicles in real time, and monitored schedule adherence. Th...

Transportable Rayleigh/Raman lidar for aerosol and water vapor profiling

NASA Astrophysics Data System (ADS)

Congeduti, Fernando; D'Aulerio, P.; Casadio, S.; Baldetti, P.; Belardinelli, F.

2001-01-01

A nighttime operating Raman/Rayleigh/Mie lidar system for the measurement of profiles of the water vapor mixing ratio and the aerosol backscatter ratio is described. The transmitter utilizes two laser beam at 532 nm and 355 nm from a Nd:YAG pulsed laser and the receiver consists of three Newtonian telescopes. Optical fibers carry the signal to the detectors. The system, which is installed in two containers, is transportable. Data are recorded with resolutions of 75-m in altitude and 1-min in time. Water vapor profiles from 200 m above the lidar altitude up to the upper troposphere and aerosol profiles form 500 m up to the lower stratosphere were obtained also at the lowest resolution. The lidar was deployed and used in the 'Target Area of the Lago Maggiore' during the MAP-SOP international campaign. Measurements taken during that campaign are reported to show the lidar performance. Improvements of the system by employing an array of nine 50-cm diameter telescopes are planned. These should effectively enhance the lidar performance.

Direct and semidirect aerosol effects of southern African biomass burning aerosol

NASA Astrophysics Data System (ADS)

Sakaeda, Naoko; Wood, Robert; Rasch, Philip J.

2011-06-01

Direct and semidirect radiative effects of biomass burning aerosols from southern African fires during July-October are investigated using 20 year runs of the Community Atmospheric Model (CAM) coupled to a slab ocean model. Aerosol optical depth is constrained using observations in clear skies from Moderate Resolution Imaging Spectroradiometer (MODIS) and for aerosol layers above clouds from Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO). Over the ocean, where the aerosol layers are primarily located above cloud, negative top of atmosphere (TOA) semidirect radiative effects associated with increased low cloud cover dominate over a weaker positive all-sky direct radiative effect (DRE). In contrast, over the land where the aerosols are often below or within cloud layers, reductions in cloud liquid water path (LWP) lead to a positive semidirect radiative effect that dominates over a near-zero DRE. Over the ocean, the cloud response can be understood as a response to increased lower tropospheric stability (LTS) which is caused both by radiative heating in overlying layers and surface cooling in response to direct aerosol forcing. The marine cloud changes are robust to changes in the cloud parameterization (removal of the hard-wired dependence of clouds on LTS), suggesting that they are physically realistic. Over land, decreased LWP is consistent with weaker convection driven by increased static stability. Over the entire region the overall TOA radiative effect from the biomass burning aerosols is almost zero due to opposing effects over the land and ocean. However, the surface forcing is strongly negative, which leads to a reduction in precipitation and also a reduction in sensible heat flux. The former is primarily realized through reductions in convective precipitation on both the southern and northern flanks of the convective precipitation region spanning the equatorial rain forest and the Intertropical Convergence Zone (ITCZ) in the

The accuracy of the CAD system using intraoral and extraoral scanners for designing of fixed dental prostheses.

PubMed

Shimizu, Sakura; Shinya, Akikazu; Kuroda, Soichi; Gomi, Harunori

2017-07-26

The accuracy of prostheses affects clinical success and is, in turn, affected by the accuracy of the scanner and CAD programs. Thus, their accuracy is important. The first aim of this study was to evaluate the accuracy of an intraoral scanner with active triangulation (Cerec Omnicam), an intraoral scanner with a confocal laser (3Shape Trios), and an extraoral scanner with active triangulation (D810). The second aim of this study was to compare the accuracy of the digital crowns designed with two different scanner/CAD combinations. The accuracy of the intraoral scanners and extraoral scanner was clinically acceptable. Marginal and internal fit of the digital crowns fabricated using the intraoral scanner and CAD programs were inferior to those fabricated using the extraoral scanner and CAD programs.

Solid aerosol generator

DOEpatents

Prescott, Donald S.; Schober, Robert K.; Beller, John

1992-01-01

An improved solid aerosol generator used to produce a gas borne stream of dry, solid particles of predetermined size and concentration. The improved solid aerosol generator nebulizes a feed solution of known concentration with a flow of preheated gas and dries the resultant wet heated aerosol in a grounded, conical heating chamber, achieving high recovery and flow rates.

Aerosol distribution apparatus

DOEpatents

Hanson, W.D.

An apparatus for uniformly distributing an aerosol to a plurality of filters mounted in a plenum, wherein the aerosol and air are forced through a manifold system by means of a jet pump and released into the plenum through orifices in the manifold. The apparatus allows for the simultaneous aerosol-testing of all the filters in the plenum.

Listeria monocytogenes CadC Regulates Cadmium Efflux and Fine-tunes Lipoprotein Localization to Escape the Host Immune Response and Promote Infection.

PubMed

Pombinho, Rita; Camejo, Ana; Vieira, Ana; Reis, Olga; Carvalho, Filipe; Almeida, Maria Teresa; Pinheiro, Jorge Campos; Sousa, Sandra; Cabanes, Didier

2017-05-01

Listeria monocytogenes is a major intracellular human foodborne bacterial pathogen. We previously revealed L. monocytogenes cadC as highly expressed during mouse infection. Here we show that L. monocytogenes CadC is a sequence-specific, DNA-binding and cadmium-dependent regulator of CadA, an efflux pump conferring cadmium resistance. CadC but not CadA is required for L. monocytogenes infection in vivo. Interestingly, CadC also directly represses lspB, a gene encoding a lipoprotein signal peptidase whose expression appears detrimental for infection. lspB overexpression promotes the release of the LpeA lipoprotein to the extracellular medium, inducing tumor necrosis factor α and interleukin 6 expression, thus impairing L. monocytogenes survival in macrophages. We propose that L. monocytogenes uses CadC to repress lspB expression during infection to avoid LpeA exposure to the host immune system, diminishing inflammatory cytokine expression and promoting intramacrophagic survival and virulence. CadC appears as the first metal efflux pump regulator repurposed during infection to fine-tune lipoprotein processing and host responses. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Light irradiance through novel CAD-CAM block materials and degree of conversion of composite cements.

PubMed

Lise, Diogo Pedrollo; Van Ende, Annelies; De Munck, Jan; Yoshihara, Kumiko; Nagaoka, Noriyuki; Cardoso Vieira, Luiz Clovis; Van Meerbeek, Bart

2018-02-01

To assess light irradiance (LI) delivered by two light-curing units (LCU's) and to measure the degree of conversion (DC) of three composite cements, when cured through different thicknesses of two novel CAD-CAM block materials. 100-μm-thick films of a dual-curable composite cement (G-CEM LinkAce, GC), a light-curable flowable resin-based composite (RBC) (G-ænial Universal Flo, GC) and a micro-hybrid RBC (G-ænial Posterior, GC) were investigated as luting agents. Two 'polymer-ceramic' CAD-CAM blocks (Cerasmart, GC; Enamic, Vita Zahnfabrik) were sectioned in slabs with different thicknesses (1, 3 and 5mm). LI at the bottom of the specimens was measured using a calibrated spectrometer, while being light-cured through the CAD-CAM block slabs for 40s with a low- (±500mW/cm 2 ) or high- (±1,600mW/cm 2 ) irradiance LCU (n=5). After light-curing, micro-Raman spectra of the composite films were acquired to determine DC at 5min, 10min, 1h and 24h. LI data were statistically analyzed by Kruskal-Wallis followed by post-hoc comparisons, while a linear mixed-effect model was applied for the DC analysis. In addition, the CAD-CAM blocks ultrastructure was characterized upon argon-ion slicing using scanning transmission electron microscopy (STEM). Finally, light transmission (LT) through each CAD-CAM block material was assessed using a spectrophotometer. Curing-light attenuation and DC were significantly influenced by thickness and type of the overlying material. LCU only had a significant effect on DC of the micro-hybrid RBC. DC significantly increased over time for all composite cements. CAD-CAM block structural analysis revealed a relatively small and homogenous filler configuration (mean filler size of 0.2-0.5μm) for Cerasmart, while Enamic contained ceramic grains varying in shape and size (1-10μm), which were interconnected by the polymer-based network. LT was much higher at a wavelength range of 300-800nm for Cerasmart than for Enamic. Light-curable composite cements

Introduction to CAD/Computers. High-Technology Training Module.

ERIC Educational Resources Information Center

Lockerby, Hugh

This learning module for an eighth-grade introductory technology course is designed to help teachers introduce students to computer-assisted design (CAD) in a communications unit on graphics. The module contains a module objective and five specific objectives, a content outline, suggested instructor methodology, student activities, a list of six…

simplified aerosol representations in global modeling

NASA Astrophysics Data System (ADS)

Kinne, Stefan; Peters, Karsten; Stevens, Bjorn; Rast, Sebastian; Schutgens, Nick; Stier, Philip

2015-04-01

The detailed treatment of aerosol in global modeling is complex and time-consuming. Thus simplified approaches are investigated, which prescribe 4D (space and time) distributions of aerosol optical properties and of aerosol microphysical properties. Aerosol optical properties are required to assess aerosol direct radiative effects and aerosol microphysical properties (in terms of their ability as aerosol nuclei to modify cloud droplet concentrations) are needed to address the indirect aerosol impact on cloud properties. Following the simplifying concept of the monthly gridded (1x1 lat/lon) aerosol climatology (MAC), new approaches are presented and evaluated against more detailed methods, including comparisons to detailed simulations with complex aerosol component modules.

Global Aerosol Optical Models and Lookup Tables for the New MODIS Aerosol Retrieval over Land

NASA Technical Reports Server (NTRS)

Levy, Robert C.; Remer, Loraine A.; Dubovik, Oleg

2007-01-01

Since 2000, MODIS has been deriving aerosol properties over land from MODIS observed spectral reflectance, by matching the observed reflectance with that simulated for selected aerosol optical models, aerosol loadings, wavelengths and geometrical conditions (that are contained in a lookup table or 'LUT'). Validation exercises have showed that MODIS tends to under-predict aerosol optical depth (tau) in cases of large tau (tau greater than 1.0), signaling errors in the assumed aerosol optical properties. Using the climatology of almucantur retrievals from the hundreds of global AERONET sunphotometer sites, we found that three spherical-derived models (describing fine-sized dominated aerosol), and one spheroid-derived model (describing coarse-sized dominated aerosol, presumably dust) generally described the range of observed global aerosol properties. The fine dominated models were separated mainly by their single scattering albedo (omega(sub 0)), ranging from non-absorbing aerosol (omega(sub 0) approx. 0.95) in developed urban/industrial regions, to neutrally absorbing aerosol (omega(sub 0) approx.90) in forest fire burning and developing industrial regions, to absorbing aerosol (omega(sub 0) approx. 0.85) in regions of savanna/grassland burning. We determined the dominant model type in each region and season, to create a 1 deg. x 1 deg. grid of assumed aerosol type. We used vector radiative transfer code to create a new LUT, simulating the four aerosol models, in four MODIS channels. Independent AERONET observations of spectral tau agree with the new models, indicating that the new models are suitable for use by the MODIS aerosol retrieval.

T null and M null genotypes of the glutathione S-transferase gene are risk factor for CAD independent of smoking

PubMed Central

Abu-Amero, Khaled K; Al-Boudari, Olayan M; Mohamed, Gamal H; Dzimiri, Nduna

2006-01-01

Background The association of the deletion in GSTT1 and GSTM1 genes with coronary artery disease (CAD) among smokers is controversial. In addition, no such investigation has previously been conducted among Arabs. Methods We genotyped 1054 CAD patients and 762 controls for GSTT1 and GSTM1 deletion by multiplex polymerase chain reaction. Both CAD and controls were Saudi Arabs. Results In the control group (n = 762), 82.3% had the T wild M wildgenotype, 9% had the Twild M null, 2.4% had the Tnull M wild and 6.3% had the Tnull M null genotype. Among the CAD group (n = 1054), 29.5% had the Twild M wild genotype, 26.6% (p < .001) had the Twild M null, 8.3% (p < .001) had the Tnull M wild and 35.6% (p < .001) had the Tnull M null genotype, indicating a significant association of the Twild M null, Tnull M wild and Tnull M null genotypes with CAD. Univariate analysis also showed that smoking, age, hypercholesterolemia and hypertriglyceridemia, diabetes mellitus, family history of CAD, hypertension and obesity are all associated with CAD, whereas gender and myocardial infarction are not. Binary logistic regression for smoking and genotypes indicated that only M null and Tnullare interacting with smoking. However, further subgroup analysis stratifying the data by smoking status suggested that genotype-smoking interactions have no effect on the development of CAD. Conclusion GSTT1 and GSTM1 null-genotypes are risk factor for CAD independent of genotype-smoking interaction. PMID:16620396

Bridging CAGD knowledge into CAD/CG applications: Mathematical theories as stepping stones of innovations

NASA Astrophysics Data System (ADS)

Gobithaasan, R. U.; Miura, Kenjiro T.; Hassan, Mohamad Nor

2014-07-01

Computer Aided Geometric Design (CAGD) which surpasses the underlying theories of Computer Aided Design (CAD) and Computer Graphics (CG) has been taught in a number of Malaysian universities under the umbrella of Mathematical Sciences' faculty/department. On the other hand, CAD/CG is taught either under the Engineering or Computer Science Faculty. Even though CAGD researchers/educators/students (denoted as contributors) have been enriching this field of study by means of article/journal publication, many fail to convert the idea into constructive innovation due to the gap that occurs between CAGD contributors and practitioners (engineers/product/designers/architects/artists). This paper addresses this issue by advocating a number of technologies that can be used to transform CAGD contributors into innovators where immediate impact in terms of practical application can be experienced by the CAD/CG practitioners. The underlying principle of solving this issue is twofold. First would be to expose the CAGD contributors on ways to turn mathematical ideas into plug-ins and second is to impart relevant CAGD theories to CAD/CG to practitioners. Both cases are discussed in detail and the final section shows examples to illustrate the importance of turning mathematical knowledge into innovations.

A CAM (continuous air monitor) sampler for collecting and assessing alpha-emitting aerosol particles

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

McFarland, A.R.; Bethel, E.L.; Ortiz, C.A.

1991-07-01

A new continuous air monitor (CAM) sampler for assessing alpha-emitting transuranic aerosol particles has been developed. The system has been designed to permit collection of particles that can potentially penetrate into the thoracic region of the human respiratory system. Wind tunnel testing of the sampler has been used to characterize the penetration of aerosol to the collection filter. Results show that greater than or equal to 50% of 10-micrograms aerodynamic equivalent diameter (AED) particles are collected by the filter at wind speeds of 0.3 to 2 m s-1 and at sampling flow rates of 28 to 113 L min-1 (1more » to 4 cfm). The deposition of 10-microns AED particles takes place primarily in the center of the filter, where the counting efficiency of the detector is highest.« less

Generating monodisperse pharmacological aerosols using the spinning-top aerosol generator.

PubMed

Biddiscombe, Martyn F; Barnes, Peter J; Usmani, Omar S

2006-01-01

Pharmacological aerosols of precisely controlled particle size and narrow dispersity can be generated using the spinning-top aerosol generator (STAG). The ability of the STAG to generate monodisperse aerosols from solutions of raw drug compounds makes it a valuable research instrument. In this paper, the versatility of this instrument has been further demonstrated by aerosolizing a range of commercially available nebulized pulmonary therapy preparations. Nebules of Flixotide (fluticasone propionate), Pulmicort (budesonide), Combivent (salbutamol sulphate and ipratropium bromide), Bricanyl (terbutaline sulphate), Atrovent(ipratropium bromide), and Salamol (salbutamol sulphate) were each mixed with ethanol and delivered to the STAG. Monodisperse drug aerosol distributions were generated with MMADs of 0.95-6.7 microm. To achieve larger particle sizes from the nebulizer drug suspensions, the STAG formed compound particle agglomerates derived from the smaller insoluble drug particles. These compound agglomerates behaved aerodynamically as a single particle, and this was verified using an aerodynamic particle sizer and an Andersen Cascade Impactor. Scanning electron microscope images demonstrated their physical structure. On the other hand using the nebulizer drug solutions, spherical particles proportional to the original droplet diameter were generated. The aerosols generated by the STAG can allow investigators to study the scientific principles of inhaled drug deposition and lung physiology for a range of therapeutic agents.

A Monte-Carlo Analysis of Organic Aerosol Volatility with Aerosol Microphysics

NASA Astrophysics Data System (ADS)

Gao, C. Y.; Tsigaridis, K.; Bauer, S. E.

2016-12-01

A newly developed box model scheme, MATRIX-VBS, includes the volatility-basis set (VBS) framework in an aerosol microphysical scheme MATRIX (Multiconfiguration Aerosol TRacker of mIXing state), which resolves aerosol mass and number concentrations and aerosol mixing state. The new scheme advanced the representation of organic aerosols in Earth system models by improving the traditional and simplistic treatment of organic aerosols as non-volatile and with a fixed size distribution. Further development includes adding the condensation of organics on coarse mode aerosols - dust and sea salt, thus making all organics in the system semi-volatile. To test and simplify the model, a Monte-Carlo analysis is performed to pin point which processes affect organics the most under which chemical and meteorological conditions. Since the model's parameterizations have the ability to capture a very wide range of conditions, from very clean to very polluted and for a wide range of meteorological conditions, all possible scenarios on Earth across the whole parameter space, including temperature, location, emissions and oxidant levels, are examined. The Monte-Carlo simulations provide quantitative information on the sensitivity of the newly developed model and help us understand how organics are affecting the size distribution, mixing state and volatility distribution at varying levels of meteorological conditions and pollution levels. In addition, these simulations give information on which parameters play a critical role in the aerosol distribution and evolution in the atmosphere and which do not, that will facilitate the simplification of the box model, an important step in its implementation in the global model.

Aerosol Optical Properties over the Oceans: Summary and Interpretation of Shadow-Band Radiometer Data from Six Cruises. Chapter 19

NASA Technical Reports Server (NTRS)

Miller, Mark A.; Reynolds, R. M.; Bartholomew, Mary Jane

2001-01-01

The aerosol scattering component of the total radiance measured at the detectors of ocean color satellites is determined with atmospheric correction algorithms. These algorithms are based on aerosol optical thickness measurements made in two channels that lie in the near-infrared portion of the electromagnetic spectrum. The aerosol properties in the near-infrared region are used because there is no significant contribution to the satellite-measured radiance from the underlying ocean surface in that spectral region. In the visible wavelength bands, the spectrum of radiation scattered from the turbid atmosphere is convolved with the spectrum of radiation scattered from the surface layers of the ocean. The radiance contribution made by aerosols in the visible bands is determined from the near-infrared measurements through the use of aerosol models and radiation transfer codes. Selection of appropriate aerosol models from the near-infrared measurements is a fundamental challenge. There are several challenges with respect to the development, improvement, and evaluation of satellite ocean-color atmospheric correction algorithms. A common thread among these challenges is the lack of over-ocean aerosol data. Until recently, one of the most important limitations has been the lack of techniques and instruments to make aerosol measurements at sea. There has been steady progress in this area over the past five years, and there are several new and promising devices and techniques for data collection. The development of new instruments and the collection of more aerosol data from over the world's oceans have brought the realization that aerosol measurements that can be directly compared with aerosol measurements from ocean color satellite measurements are difficult to obtain. There are two problems that limit these types of comparisons: the cloudiness of the atmosphere over the world's oceans and the limitations of the techniques and instruments used to collect aerosol data from

Solid aerosol generator

DOEpatents

Prescott, D.S.; Schober, R.K.; Beller, J.

1992-03-17

An improved solid aerosol generator used to produce a gas borne stream of dry, solid particles of predetermined size and concentration is disclosed. The improved solid aerosol generator nebulizes a feed solution of known concentration with a flow of preheated gas and dries the resultant wet heated aerosol in a grounded, conical heating chamber, achieving high recovery and flow rates. 2 figs.

MHDL CAD tool with fault circuit handling

NASA Astrophysics Data System (ADS)

Espinosa Flores-Verdad, Guillermo; Altamirano Robles, Leopoldo; Osorio Roque, Leticia

2003-04-01

Behavioral modeling and simulation, with Analog Hardware and Mixed Signal Description High Level Languages (MHDLs), have generated the development of diverse simulation tools that allow handling the requirements of the modern designs. These systems have million of transistors embedded and they are radically diverse between them. This tendency of simulation tools is exemplified by the development of languages for modeling and simulation, whose applications are the re-use of complete systems, construction of virtual prototypes, realization of test and synthesis. This paper presents the general architecture of a Mixed Hardware Description Language, based on the standard 1076.1-1999 IEEE VHDL Analog and Mixed-Signal Extensions known as VHDL-AMS. This architecture is novel by consider the modeling and simulation of faults. The main modules of the CAD tool are briefly described in order to establish the information flow and its transformations, starting from the description of a circuit model, going throw the lexical analysis, mathematical models generation and the simulation core, ending at the collection of the circuit behavior as simulation"s data. In addition, the incorporated mechanisms to the simulation core are explained in order to realize the handling of faults into the circuit models. Currently, the CAD tool works with algebraic and differential descriptions for the circuit models, nevertheless the language design is open to be able to handle different model types: Fuzzy Models, Differentials Equations, Transfer Functions and Tables. This applies for fault models too, in this sense the CAD tool considers the inclusion of mutants and saboteurs. To exemplified the results obtained until now, the simulated behavior of a circuit is shown when it is fault free and when it has been modified by the inclusion of a fault as a mutant or a saboteur. The obtained results allow the realization of a virtual diagnosis for mixed circuits. This language works in a UNIX system

Mobile Technology and CAD Technology Integration in Teaching Architectural Design Process for Producing Creative Product

ERIC Educational Resources Information Center

Bin Hassan, Isham Shah; Ismail, Mohd Arif; Mustafa, Ramlee

2011-01-01

The purpose of this research is to examine the effect of integrating the mobile and CAD technology on teaching architectural design process for Malaysian polytechnic architectural students in producing a creative product. The website is set up based on Caroll's minimal theory, while mobile and CAD technology integration is based on Brown and…

Roughness, surface energy, and superficial damages of CAD/CAM materials after surface treatment.

PubMed

Strasser, Thomas; Preis, Verena; Behr, Michael; Rosentritt, Martin

2018-02-05

The aim of this study was to examine the effects of surface pre-treatment on CAD/CAM materials including ceramics, zirconia, resin-infiltrated ceramic, and resin-based composite. Specimens were made of ten CAD/CAM materials (Celtra Duo, Degudent, D; Vita Suprinity, Vita, D; E.max CAD, Ivoclar-Vivadent, FL; E.max ZirCAD, Ivoclar-Vivadent, FL; Vita Enamic, Vita, D; Cerasmart, GC, B; LAVA Ultimate, 3M, D; SHOFU Block HC, SHOFU, US; Grandio Blocs, VOCO, D; BRILLIANT Crios, Coltene, CH) and pretreated to represent clinical procedures (Hf 20 s/5%; phosphoric acid 20 s/37%; Monobond etch and prime (Ivoclar-Vivadent, FL); water-cooled diamond bur (80 μm; 4 μm); Al 2 O 3 -blasting (50 μm/1 bar, 50 μm/2 bar, 120 μm/1 bar, 120 μm/2 bar); untreated; manufacturer's instructions). SEM-analysis (Phenom, FEI, NL) of the surfaces was performed (magnifications ≤ 10,000×). Roughness values R a , R z (KJ 3D, Keyence, J), and surface energy SE (OCA15 plus, SCA20, DataPhysics, D) were determined (statistics: non-parametric Mann-Whitney U test/Kruskal-Wallis test for independent specimen, α = 0.05). Kruskal-Wallis revealed significant (p < 0.001) differences for all materials with different surface treatments. Roughness ranged from R a  = 0.05 μm (VS; D4)/R z  = 0.41 μm (VS; D4) to R a  = 1.82 μm (EMA; SB120/2)/R z  = 12.05 μm (CS; SB 120/2), SE from 22.7 mN/m (VE; M) to 52.8 mN/m (CD; M). SEM analysis showed material-dependent damages after pre-treatment. Different CAD/CAM materials require individual pre-treatment for optimized and protective surface activation. Cementation is a key factor for clinical success. Given the variety of available CAD/CAM materials, specific procedures are needed.

3-D Human body models in C.A.D. : Anthropometric Aspects

NASA Astrophysics Data System (ADS)

Renaud, C.; Steck, R.; Pineau, J. C.

1986-07-01

Modeling and simulation methods of man-machine systems are developed at the laboratory by interactive infography and C.A.D. technics. In order to better apprehend the morphological variability of populations we have enriched the 3-D model with a parametric function using classical anthropometric dimensions. We have selected reference, associate and complementary dimensions : lengths, breadths, circumferences and depths, which depend on operator's tasks and characteristics of workplaces. All anthropometric values come from the International Data Bank of Human Biometry of ERGODATA System. The utilization of the parametric function brings a quick and accurate description of morphology for theoretic subjects and can be used in C.A.D. analysis.

IPAD 2: Advances in Distributed Data Base Management for CAD/CAM

NASA Technical Reports Server (NTRS)

Bostic, S. W. (Compiler)

1984-01-01

The Integrated Programs for Aerospace-Vehicle Design (IPAD) Project objective is to improve engineering productivity through better use of computer-aided design and manufacturing (CAD/CAM) technology. The focus is on development of technology and associated software for integrated company-wide management of engineering information. The objectives of this conference are as follows: to provide a greater awareness of the critical need by U.S. industry for advancements in distributed CAD/CAM data management capability; to present industry experiences and current and planned research in distributed data base management; and to summarize IPAD data management contributions and their impact on U.S. industry and computer hardware and software vendors.

Antarctic aerosols - A review

NASA Astrophysics Data System (ADS)

Shaw, Glenn E.

1988-02-01

Tropospheric aerosols with the diameter range of half a micron reside in the atmosphere for tens of days and teleconnect Antarctica with other regions by transport that reaches planetary scales of distances; thus, the aerosol on the Antarctic ice represents 'memory modules' of events that took place at regions separated from Antarctica by tens of thousands of kilometers. In terms of aerosol mass, the aerosol species include insoluble crustal products (less than 5 percent), transported sea-salt residues (highly variable but averaging about 10 percent), Ni-rich meteoric material, and anomalously enriched material with an unknown origin. Most (70-90 percent by mass) of the aerosol over the Antarctic ice shield, however, is the 'natural acid sulfate aerosol', apparently deriving from biological processes taking place in the surrounding oceans.

Characterization of urban aerosol using aerosol mass spectrometry and proton nuclear magnetic resonance spectroscopy

NASA Astrophysics Data System (ADS)

Cleveland, M. J.; Ziemba, L. D.; Griffin, R. J.; Dibb, J. E.; Anderson, C. H.; Lefer, B.; Rappenglück, B.

2012-07-01

Particulate matter was measured during August and September of 2006 in Houston as part of the Texas Air Quality Study II Radical and Aerosol Measurement Project. Aerosol size and composition were determined using an Aerodyne quadrupole aerosol mass spectrometer. Aerosol was dominated by sulfate (4.1 ± 2.6 μg m-3) and organic material (5.5 ± 4.0 μg m-3), with contributions of organic material from both primary (˜32%) and secondary (˜68%) sources. Secondary organic aerosol appears to be formed locally. In addition, 29 aerosol filter samples were analyzed using proton nuclear magnetic resonance (1H NMR) spectroscopy to determine relative concentrations of organic functional groups. Houston aerosols are less oxidized than those observed elsewhere, with smaller relative contributions of carbon-oxygen double bonds. These particles do not fit 1H NMR source apportionment fingerprints for identification of secondary, marine, and biomass burning organic aerosol, suggesting that a new fingerprint for highly urbanized and industrially influenced locations be established.

Bond strength of novel CAD/CAM restorative materials to self-adhesive resin cement: the effect of surface treatments.

PubMed

Elsaka, Shaymaa E

2014-12-01

To evaluate the effect of different surface treatments on the microtensile bond strength (μTBS) of novel CAD/CAM restorative materials to self-adhesive resin cement. Two types of CAD/CAM restorative materials (Vita Enamic [VE] and Lava Ultimate [LU]) were used. The specimens were divided into five groups in each test according to the surface treatment performed; Gr 1 (control; no treatment), Gr 2 (sandblasted [SB]), Gr 3 (SB+silane [S]), Gr 4 (hydrofluoric acid [HF]), and Gr 5 (HF+S). A dual-curing self-adhesive resin cement (Bifix SE [BF]) was applied to each group for testing the adhesion after 24 h of storage in distilled water or after 30 days using the μTBS test. Following fracture testing, specimens were examined with a stereomicroscope and SEM. Surface roughness and morphology of the CAD/CAM restorative materials were characterized after treatment. Data were analyzed using ANOVA and Tukey's test. The surface treatment, type of CAD/CAM restorative material, and water storage periods showed a significant effect on the μTBS (p<0.001). For the LU/BF system, there was no significant difference in the bond strength values between different surface treatments (p>0.05). On the other hand, for the VE/BF system, surface treatment with HF+S showed higher bond strength values compared with SB and HF surface treatments (p<0.05). Surface roughness and SEM analyses showed that the surface topography of CAD/CAM restorative materials was modified after treatments. The effect of surface treatments on the bond strength of novel CAD/CAM restorative materials to resin cement is material dependent. The VE/BF CAD/CAM material provided higher bond strength values compared with the LU/BF CAD/CAM material.

Effect of professional dental prophylaxis on the surface gloss and roughness of CAD/CAM restorative materials.

PubMed

Sugiyama, Toshiko; Kameyama, Atsushi; Enokuchi, Tomoka; Haruyama, Akiko; Chiba, Aoi; Sugiyama, Setsuko; Hosaka, Makoto; Takahashi, Toshiyuki

2017-06-01