An Investigation of the Incorporation of Virtual Microscopy in the Cytotechnology Educational Curriculum

ERIC Educational Resources Information Center

Mukherjee, Maheswari S.

2012-01-01

Traditionally, cytotechnology (CT) students have been trained by using light microscopy (LM) and glass slides. However, this method of training has some drawbacks. Several other educational programs with similar issues have incorporated virtual microscopy (VM) in their curricula. In VM, the specimens on glass slides are converted into virtual…

Study of a control strategy for grid side converter in doubly- fed wind power system

NASA Astrophysics Data System (ADS)

Zhu, D. J.; Tan, Z. L.; Yuan, F.; Wang, Q. Y.; Ding, M.

2016-08-01

The grid side converter is an important part of the excitation system of doubly-fed asynchronous generator used in wind power system. As a three-phase voltage source PWM converter, it can not only transfer slip power in the form of active power, but also adjust the reactive power of the grid. This paper proposed a control approach for improving its performance. In this control approach, the dc voltage is regulated by a sliding mode variable structure control scheme and current by a variable structure controller based on the input output linearization. The theoretical bases of the sliding mode variable structure control were introduced, and the stability proof was presented. Switching function of the system has been deduced, sliding mode voltage controller model has been established, and the output of the outer voltage loop is the instruction of the inner current loop. Affine nonlinear model of two input two output equations on d-q axis for current has been established its meeting conditions of exact linearization were proved. In order to improve the anti-jamming capability of the system, a variable structure control was added in the current controller, the control law was deduced. The dual-loop control with sliding mode control in outer voltage loop and linearization variable structure control in inner current loop was proposed. Simulation results demonstrate the effectiveness of the proposed control strategy even during the dc reference voltage and system load variation.

Efficiency of Do-It-Yourself Slide-Tape Programs as an Alternative to the Lecture in Medical Biochemistry

ERIC Educational Resources Information Center

Baggott, James; And Others

1977-01-01

Evidence suggests that a well-developed lecture script on a topic in medical biochemistry can quickly and easily be converted into an effective slide-tape program that is as educationally effective and well-received as one that is painstakingly tailored to the nature of the medium. (LBH)

Safely Converting an Entire Academic Medical Center From Sliding Scale to Basal Bolus Insulin via Implementation of the eGlycemic Management System.

PubMed

Newsom, Rosalina; Patty, Christopher; Camarena, Emma; Sawyer, Regina; McFarland, Raymie; Gray, Thomas; Mabrey, Melanie

2018-01-01

Hyperglycemia is common in the inpatient setting and providers frequently rely on sliding scale insulin. This case study reviews the experience of one hospital moving from high utilization of sliding scale to basal bolus insulin therapy. This Retrospective Quality Improvement Study describes the journey of clinicians at a 580-bed hospital to convert from high usage of SSI to BBI. Hyperglycemic adult patients prescribed insulin, with/without a diagnosis of diabetes, were included. Data over the first year showed that patients treated with Glucommander (GM) spent more time in the target range of 70-180 mg/dL than patients treated with non-Glucommander (non-GM), with 2,434 fewer hypoglycemic events and 40,589 fewer hyperglycemic events. Prior to implementation of GM, SSI was close to 95%, BBI at 5%. Within the first month of use, 96% usage of BBI was achieved. Reduction of hypoglycemic events (% of BG < 70 mg/dL) by 21% with 2.16% non-GM compared to GM at 1.74% and severe Hypoglycemia (% of BG < 50 mg/dL) by 50% in the ICU 3% non-GM compared to GM at 1.5%. In addition, patients treated with GM had a shorter LOS than patients treated with non-GM by 3.18 days and used 47.4% less point of care tests per patient. Glycemic management improved with use of eGMS. The conversion from SSI to BBI enhanced overall patient safety, eliminated the time and effort otherwise required when manually titrating insulin and reduced overall cost of care for patients on insulin therapy.

Automated Selection of Hotspots (ASH): enhanced automated segmentation and adaptive step finding for Ki67 hotspot detection in adrenal cortical cancer.

PubMed

Lu, Hao; Papathomas, Thomas G; van Zessen, David; Palli, Ivo; de Krijger, Ronald R; van der Spek, Peter J; Dinjens, Winand N M; Stubbs, Andrew P

2014-11-25

In prognosis and therapeutics of adrenal cortical carcinoma (ACC), the selection of the most active areas in proliferative rate (hotspots) within a slide and objective quantification of immunohistochemical Ki67 Labelling Index (LI) are of critical importance. In addition to intratumoral heterogeneity in proliferative rate i.e. levels of Ki67 expression within a given ACC, lack of uniformity and reproducibility in the method of quantification of Ki67 LI may confound an accurate assessment of Ki67 LI. We have implemented an open source toolset, Automated Selection of Hotspots (ASH), for automated hotspot detection and quantification of Ki67 LI. ASH utilizes NanoZoomer Digital Pathology Image (NDPI) splitter to convert the specific NDPI format digital slide scanned from the Hamamatsu instrument into a conventional tiff or jpeg format image for automated segmentation and adaptive step finding hotspots detection algorithm. Quantitative hotspot ranking is provided by the functionality from the open source application ImmunoRatio as part of the ASH protocol. The output is a ranked set of hotspots with concomitant quantitative values based on whole slide ranking. We have implemented an open source automated detection quantitative ranking of hotspots to support histopathologists in selecting the 'hottest' hotspot areas in adrenocortical carcinoma. To provide wider community easy access to ASH we implemented a Galaxy virtual machine (VM) of ASH which is available from http://bioinformatics.erasmusmc.nl/wiki/Automated_Selection_of_Hotspots . The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_216.

DPS Discovery Slide Sets for the Introductory Astronomy Instructor

NASA Astrophysics Data System (ADS)

Meinke, Bonnie K.; Jackson, Brian; Buxner, Sanlyn; Horst, Sarah; Brain, David; Schneider, Nicholas M.

2016-10-01

The DPS actively supports the E/PO needs of the society's membership, including those at the front of the college classroom. The DPS Discovery Slide Sets are an opportunity for instructors to put the latest planetary science into their lectures and for scientists to get their exciting results to college students.In an effort to keep the astronomy classroom apprised of the fast moving field of planetary science, the Division for Planetary Sciences (DPS) has developed "DPS Discoveries", which are 3-slide presentations that can be incorporated into college lectures. The slide sets are targeted at the Introductory Astronomy undergraduate level. Each slide set consists of three slides which cover a description of the discovery, a discussion of the underlying science, and a presentation of the big picture implications of the discovery, with a fourth slide that includes links to associated press releases, images, and primary sources. Topics span all subdisciplines of planetary science, and 26 sets are available in Farsi and Spanish. We intend for these slide sets to help Astronomy 101 instructors include new developments (not yet in their textbooks) into the broader context of the course. If you need supplemental material for your classroom, please checkout the archived collection: http://dps.aas.org/education/dpsdiscMore slide sets are now in development and will be available soon! In the meantime, we seek input, feedback, and help from the DPS membership to add fresh slide sets to the series and to connect the college classroom to YOUR science. It's easy to get involved - we'll provide a content template, tips and tricks for a great slide set, and pedagogy reviews. Talk to a coauthor to find out how you can disseminate your science or get involved in E/PO with your contributions.

Coral disease and health workshop: Coral Histopathology II, July 12-14, 2005

USGS Publications Warehouse

Galloway, S.B.; Woodley, Cheryl M.; McLaughlin, S.M.; Work, Thierry M.; Bochsler, V.S.; Meteyer, Carol U.; Sileo, Louis; Peters, E.C.; Kramarsky-Winters, E.; Morado, J. Frank; Parnell, P.G.; Rotstein, D.S.; Harely, R.A.; Reynolds, T.L.

2005-01-01

An exciting highlight of this meeting was provided by Professor Robert Ogilvie (MUSC Department of Cell Biology and Anatomy) when he introduced participants to a new digital technology that is revolutionizing histology and histopathology in the medical field. The Virtual Slide technology creates digital images of histological tissue sections by computer scanning actual slides in high definition and storing the images for retrieval and viewing. Virtual slides now allow any investigator with access to a computer and the web to view, search, annotate and comment on the same tissue sections in real time. Medical and veterinary slide libraries across the country are being converted into virtual slides to enhance biomedical education, research and diagnosis. The coral health and disease researchers at this workshop deem virtual slides as a significant way to increase capabilities in coral histology and a means for pathology consultations on coral disease cases on a global scale. 

How to Transform Mechanical Work into Electrical Energy Using a Capacitor

ERIC Educational Resources Information Center

Skumiel, A.

2011-01-01

In this paper the method of converting mechanical work into electrical energy with the participation of a preliminarily charged condenser while the electrodes are sliding in it is presented. Using this method, we can obtain a considerable increase of converted electrical power, depending on the initial energy of the charged condenser, distance…

Chiral cell sliding drives left-right asymmetric organ twisting

PubMed Central

Inaki, Mikiko; Hatori, Ryo; Nakazawa, Naotaka; Okumura, Takashi; Ishibashi, Tomoki; Kikuta, Junichi; Ishii, Masaru

2018-01-01

Polarized epithelial morphogenesis is an essential process in animal development. While this process is mostly attributed to directional cell intercalation, it can also be induced by other mechanisms. Using live-imaging analysis and a three-dimensional vertex model, we identified ‘cell sliding,’ a novel mechanism driving epithelial morphogenesis, in which cells directionally change their position relative to their subjacent (posterior) neighbors by sliding in one direction. In Drosophila embryonic hindgut, an initial left-right (LR) asymmetry of the cell shape (cell chirality in three dimensions), which occurs intrinsically before tissue deformation, is converted through LR asymmetric cell sliding into a directional axial twisting of the epithelial tube. In a Drosophila inversion mutant showing inverted cell chirality and hindgut rotation, cell sliding occurs in the opposite direction to that in wild-type. Unlike directional cell intercalation, cell sliding does not require junctional remodeling. Cell sliding may also be involved in other cases of LR-polarized epithelial morphogenesis. PMID:29891026

Chiral cell sliding drives left-right asymmetric organ twisting.

PubMed

Inaki, Mikiko; Hatori, Ryo; Nakazawa, Naotaka; Okumura, Takashi; Ishibashi, Tomoki; Kikuta, Junichi; Ishii, Masaru; Matsuno, Kenji; Honda, Hisao

2018-06-12

Polarized epithelial morphogenesis is an essential process in animal development. While this process is mostly attributed to directional cell intercalation, it can also be induced by other mechanisms. Using live-imaging analysis and a three-dimensional vertex model, we identified 'cell sliding,' a novel mechanism driving epithelial morphogenesis, in which cells directionally change their position relative to their subjacent (posterior) neighbors by sliding in one direction. In Drosophila embryonic hindgut, an initial left-right (LR) asymmetry of the cell shape (cell chirality in three dimensions), which occurs intrinsically before tissue deformation, is converted through LR asymmetric cell sliding into a directional axial twisting of the epithelial tube. In a Drosophila inversion mutant showing inverted cell chirality and hindgut rotation, cell sliding occurs in the opposite direction to that in wild-type. Unlike directional cell intercalation, cell sliding does not require junctional remodeling. Cell sliding may also be involved in other cases of LR-polarized epithelial morphogenesis. © 2018, Inaki et al.

Prediction Study on Anti-Slide Control of Railway Vehicle Based on RBF Neural Networks

NASA Astrophysics Data System (ADS)

Yang, Lijun; Zhang, Jimin

While railway vehicle braking, Anti-slide control system will detect operating status of each wheel-sets e.g. speed difference and deceleration etc. Once the detected value on some wheel-set is over pre-defined threshold, brake effort on such wheel-set will be adjusted automatically to avoid blocking. Such method takes effect on guarantee safety operation of vehicle and avoid wheel-set flatness, however it cannot adapt itself to the rail adhesion variation. While wheel-sets slide, the operating status is chaotic time series with certain law, and can be predicted with the law and experiment data in certain time. The predicted values can be used as the input reference signals of vehicle anti-slide control system, to judge and control the slide status of wheel-sets. In this article, the RBF neural networks is taken to predict wheel-set slide status in multi-step with weight vector adjusted based on online self-adaptive algorithm, and the center & normalizing parameters of active function of the hidden unit of RBF neural networks' hidden layer computed with K-means clustering algorithm. With multi-step prediction simulation, the predicted signal with appropriate precision can be used by anti-slide system to trace actively and adjust wheel-set slide tendency, so as to adapt to wheel-rail adhesion variation and reduce the risk of wheel-set blocking.

NASA SMD E/PO Community Addresses the needs of the Higher Ed Community: Introducing Slide sets for the Introductory Earth and Space Science Instructor

NASA Astrophysics Data System (ADS)

Buxner, S.; Meinke, B. K.; Brain, D.; Schneider, N. M.; Schultz, G. R.; Smith, D. A.; Grier, J.; Shipp, S. S.

2014-12-01

The NASA Science Mission Directorate (SMD) Science Education and Public Outreach (E/PO) community and Forums work together to bring the cutting-edge discoveries of NASA Astrophysics and Planetary Science missions to the introductory astronomy college classroom. These mission- and grant-based E/PO programs are uniquely poised to foster collaboration between scientists with content expertise and educators with pedagogy expertise. We present two new opportunities for college instructors to bring the latest NASA discoveries in Space Science into their classrooms. The NASA Science Mission Directorate (SMD) Astrophysics Education and Public Outreach Forum is coordinating the development of a pilot series of slide sets to help Astronomy 101 instructors incorporate new discoveries in their classrooms. The "Astro 101 slide sets" are presentations 5-7 slides in length on a new development or discovery from a NASA Astrophysics mission relevant to topics in introductory astronomy courses. We intend for these slide sets to help Astronomy 101 instructors include new developments (discoveries not yet in their textbooks) into the broader context of the course. In a similar effort to keep the astronomy classroom apprised of the fast moving field of planetary science, the Division of Planetary Sciences (DPS) has developed the Discovery slide sets, which are 3-slide presentations that can be incorporated into college lectures. The slide sets are targeted at the Introductory Astronomy undergraduate level. Each slide set consists of three slides which cover a description of the discovery, a discussion of the underlying science, and a presentation of the big picture implications of the discovery, with a fourth slide includes links to associated press releases, images, and primary sources. Topics span all subdisciplines of planetary science, and sets are available in Farsi and Spanish. The NASA SMD Planetary Science Forum has recently partnered with the DPS to continue producing the Discovery slides and connect them to NASA mission science.

"Discoveries in Planetary Sciences": Slide Sets Highlighting New Advances for Astronomy Educators

NASA Astrophysics Data System (ADS)

Brain, David; Schneider, N.; Molaverdikhani, K.; Afsharahmadi, F.

2012-10-01

We present two new features of an ongoing effort to bring recent newsworthy advances in planetary science to undergraduate lecture halls. The effort, called 'Discoveries in Planetary Sciences', summarizes selected recently announced discoveries that are 'too new for textbooks' in the form of 3-slide PowerPoint presentations. The first slide describes the discovery, the second slide discusses the underlying planetary science concepts at a level appropriate for students of 'Astronomy 101', and the third presents the big picture implications of the discovery. A fourth slide includes links to associated press releases, images, and primary sources. This effort is generously sponsored by the Division for Planetary Sciences of the American Astronomical Society, and the slide sets are available at http://dps.aas.org/education/dpsdisc/ for download by undergraduate instructors or any interested party. Several new slide sets have just been released, and we summarize the topics covered. The slide sets are also being translated into languages other than English (including Spanish and Farsi), and we will provide an overview of the translation strategy and process. Finally, we will present web statistics on how many people are using the slide sets, as well as individual feedback from educators.

Adaptive fuzzy sliding control of single-phase PV grid-connected inverter.

PubMed

Fei, Juntao; Zhu, Yunkai

2017-01-01

In this paper, an adaptive fuzzy sliding mode controller is proposed to control a two-stage single-phase photovoltaic (PV) grid-connected inverter. Two key technologies are discussed in the presented PV system. An incremental conductance method with adaptive step is adopted to track the maximum power point (MPP) by controlling the duty cycle of the controllable power switch of the boost DC-DC converter. An adaptive fuzzy sliding mode controller with an integral sliding surface is developed for the grid-connected inverter where a fuzzy system is used to approach the upper bound of the system nonlinearities. The proposed strategy has strong robustness for the sliding mode control can be designed independently and disturbances can be adaptively compensated. Simulation results of a PV grid-connected system verify the effectiveness of the proposed method, demonstrating the satisfactory robustness and performance.

Optimal Control Allocation with Load Sensor Feedback for Active Load Suppression

NASA Technical Reports Server (NTRS)

Miller, Christopher

2017-01-01

These slide sets describe the OCLA formulation and associated algorithms as a set of new technologies in the first practical application of load limiting flight control utilizing load feedback as a primary control measurement. Slide set one describes Experiment Development and slide set two describes Flight-Test Performance.

Adaptive fuzzy sliding control of single-phase PV grid-connected inverter

PubMed Central

Zhu, Yunkai

2017-01-01

In this paper, an adaptive fuzzy sliding mode controller is proposed to control a two-stage single-phase photovoltaic (PV) grid-connected inverter. Two key technologies are discussed in the presented PV system. An incremental conductance method with adaptive step is adopted to track the maximum power point (MPP) by controlling the duty cycle of the controllable power switch of the boost DC-DC converter. An adaptive fuzzy sliding mode controller with an integral sliding surface is developed for the grid-connected inverter where a fuzzy system is used to approach the upper bound of the system nonlinearities. The proposed strategy has strong robustness for the sliding mode control can be designed independently and disturbances can be adaptively compensated. Simulation results of a PV grid-connected system verify the effectiveness of the proposed method, demonstrating the satisfactory robustness and performance. PMID:28797060

The effect of seasonal variation on the performances of grid connected photovoltaic system in southern of Algeria

NASA Astrophysics Data System (ADS)

Zaghba, L.; Khennane, M.; Terki, N.; Borni, A.; Bouchakour, A.; Fezzani, A.; Mahamed, I. Hadj; Oudjana, S. H.

2017-02-01

This paper presents modeling, simulation, and analysis evaluation of the grid-connected PV generation system performance under MATLAB/Simulink. The objective is to study the effect of seasonal variation on the performances of grid connected photovoltaic system in southern of Algeria. This system works with a power converter. This converter allows the connection to the network and extracts maximum power from photovoltaic panels with the MPPT algorithm based on robust neuro-fuzzy sliding approach. The photovoltaic energy produced by the PV generator will be completely injected on the network. Simulation results show that the system controlled by the neuro-fuzzy sliding adapts to changing external disturbances and show their effectiveness not only for continued maximum power point but also for response time and stability.

Student perceptions of digital versus traditional slide use in undergraduate education.

PubMed

Solberg, Brooke L

2012-01-01

Digitized slides provide a number of intriguing benefits for educators. Before their implementation, however, educators should consider student opinion related to their use. This mixed-methods study directly compared Medical Laboratory Science (MLS) student perceptions of learning experiences in both digital and traditional slide laboratory settings. Results suggested that the majority of students preferred learning with digital slides, and numerous reasons for this preference were identified. Survey responses indicated that students using digital slides tended to view their performances, instructor feedback, and their learning environment more positively than students using traditional slides. Apprehensions about digital slide use were also detected from students preferring traditional slides. These findings provide a guide on how best to exploit both digital and traditional slides in an educational setting.

Five years of experience teaching pathology to dental students using the WebMicroscope

PubMed Central

2011-01-01

Background We describe development and evaluation of the user-friendly web based virtual microscopy - WebMicroscope for teaching and learning dental students basic and oral pathology. Traditional students microscopes were replaced by computer workstations. Methods The transition of the basic and oral pathology courses from light to virtual microscopy has been completed gradually over a five-year period. A pilot study was conducted in academic year 2005/2006 to estimate the feasibility of integrating virtual microscopy into a traditional light microscopy-based pathology course. The entire training set of glass slides was subsequently converted to virtual slides and placed on the WebMicroscope server. Giving access to fully digitized slides on the web with a browser and a viewer plug-in, the computer has become a perfect companion of the student. Results The study material consists now of over 400 fully digitized slides which covering 15 entities in basic and systemic pathology and 15 entities in oral pathology. Digitized slides are linked with still macro- and microscopic images, organized with clinical information into virtual cases and supplemented with text files, syllabus, PowerPoint presentations and animations on the web, serving additionally as material for individual studies. After their examinations, the students rated the use of the software, quality of the images, the ease of handling the images, and the effective use of virtual slides during the laboratory practicals. Responses were evaluated on a standardized scale. Because of the positive opinions and support from the students, the satisfaction surveys had shown a progressive improvement over the past 5 years. The WebMicroscope as a didactic tool for laboratory practicals was rated over 8 on a 1-10 scale for basic and systemic pathology and 9/10 for oral pathology especially as various students’ suggestions were implemented. Overall, the quality of the images was rated as very good. Conclusions An overwhelming majority of our students regarded a possibility of using virtual slides at their convenience as highly desirable. Our students and faculty consider the use of the virtual microscope for the study of basic as well as oral pathology as a significant improvement over the light microscope. PMID:21489183

Effect of Physicochemical Anomalies of Soda-Lime Silicate Slides on Biomolecule Immobilization

DTIC Science & Technology

2009-01-01

roughness. EXPERIMENTAL SECTION Materials. Standard soda - lime glass microscope slides were obtained from several sources (Table 1). Rabbit anti-lipid A...had changed, confir- mation was obtained from the manufacturers that slides in set A1 were the same soda - lime glass slides as those in set A2 and...manufacture of soda - lime glass slides. X-ray Photoelectron Spectroscopy (XPS). To identify el- emental disparities in the glass surface, relative atomic

The myosin converter domain modulates muscle performance.

PubMed

Swank, Douglas M; Knowles, Aileen F; Suggs, Jennifer A; Sarsoza, Floyd; Lee, Annie; Maughan, David W; Bernstein, Sanford I

2002-04-01

Myosin is the molecular motor that powers muscle contraction as a result of conformational changes during its mechanochemical cycle. We demonstrate that the converter, a compact structural domain that differs in sequence between Drosophila melanogaster myosin isoforms, dramatically influences the kinetic properties of myosin and muscle fibres. Transgenic replacement of the converter in the fast indirect flight muscle with the converter from an embryonic muscle slowed muscle kinetics, forcing a compensatory reduction in wing beat frequency to sustain flight. Conversely, replacing the embryonic converter with the flight muscle converter sped up muscle kinetics and increased maximum power twofold, compared to flight muscles expressing the embryonic myosin isoform. The substitutions also dramatically influenced in vitro actin sliding velocity, suggesting that the converter modulates a rate-limiting step preceding cross-bridge detachment. Our integrative analysis demonstrates that isoform-specific differences in the myosin converter allow different muscle types to meet their specific locomotion demands.

Open source tools for management and archiving of digital microscopy data to allow integration with patient pathology and treatment information.

PubMed

Khushi, Matloob; Edwards, Georgina; de Marcos, Diego Alonso; Carpenter, Jane E; Graham, J Dinny; Clarke, Christine L

2013-02-12

Virtual microscopy includes digitisation of histology slides and the use of computer technologies for complex investigation of diseases such as cancer. However, automated image analysis, or website publishing of such digital images, is hampered by their large file sizes. We have developed two Java based open source tools: Snapshot Creator and NDPI-Splitter. Snapshot Creator converts a portion of a large digital slide into a desired quality JPEG image. The image is linked to the patient's clinical and treatment information in a customised open source cancer data management software (Caisis) in use at the Australian Breast Cancer Tissue Bank (ABCTB) and then published on the ABCTB website (http://www.abctb.org.au) using Deep Zoom open source technology. Using the ABCTB online search engine, digital images can be searched by defining various criteria such as cancer type, or biomarkers expressed. NDPI-Splitter splits a large image file into smaller sections of TIFF images so that they can be easily analysed by image analysis software such as Metamorph or Matlab. NDPI-Splitter also has the capacity to filter out empty images. Snapshot Creator and NDPI-Splitter are novel open source Java tools. They convert digital slides into files of smaller size for further processing. In conjunction with other open source tools such as Deep Zoom and Caisis, this suite of tools is used for the management and archiving of digital microscopy images, enabling digitised images to be explored and zoomed online. Our online image repository also has the capacity to be used as a teaching resource. These tools also enable large files to be sectioned for image analysis. The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5330903258483934.

Open source tools for management and archiving of digital microscopy data to allow integration with patient pathology and treatment information

PubMed Central

2013-01-01

Background Virtual microscopy includes digitisation of histology slides and the use of computer technologies for complex investigation of diseases such as cancer. However, automated image analysis, or website publishing of such digital images, is hampered by their large file sizes. Results We have developed two Java based open source tools: Snapshot Creator and NDPI-Splitter. Snapshot Creator converts a portion of a large digital slide into a desired quality JPEG image. The image is linked to the patient’s clinical and treatment information in a customised open source cancer data management software (Caisis) in use at the Australian Breast Cancer Tissue Bank (ABCTB) and then published on the ABCTB website (http://www.abctb.org.au) using Deep Zoom open source technology. Using the ABCTB online search engine, digital images can be searched by defining various criteria such as cancer type, or biomarkers expressed. NDPI-Splitter splits a large image file into smaller sections of TIFF images so that they can be easily analysed by image analysis software such as Metamorph or Matlab. NDPI-Splitter also has the capacity to filter out empty images. Conclusions Snapshot Creator and NDPI-Splitter are novel open source Java tools. They convert digital slides into files of smaller size for further processing. In conjunction with other open source tools such as Deep Zoom and Caisis, this suite of tools is used for the management and archiving of digital microscopy images, enabling digitised images to be explored and zoomed online. Our online image repository also has the capacity to be used as a teaching resource. These tools also enable large files to be sectioned for image analysis. Virtual Slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/5330903258483934 PMID:23402499

Emergence of flagellar beating from the collective behavior of individual ATP-powered dyneins

NASA Astrophysics Data System (ADS)

Namdeo, S.; Onck, P. R.

2016-10-01

Flagella are hair-like projections from the surface of eukaryotic cells, and they play an important role in many cellular functions, such as cell-motility. The beating of flagella is enabled by their internal architecture, the axoneme, and is powered by a dense distribution of motor proteins, dyneins. The dyneins deliver the required mechanical work through the hydrolysis of ATP. Although the dynein-ATP cycle, the axoneme microstructure, and the flagellar-beating kinematics are well studied, their integration into a coherent picture of ATP-powered flagellar beating is still lacking. Here we show that a time-delayed negative-work-based switching mechanism is able to convert the individual sliding action of hundreds of dyneins into a regular overall beating pattern leading to propulsion. We developed a computational model based on a minimal representation of the axoneme consisting of two representative doublet microtubules connected by nexin links. The relative sliding of the microtubules is incorporated by modeling two groups of ATP-powered dyneins, each responsible for sliding in opposite directions. A time-delayed switching mechanism is postulated, which is key in converting the local individual sliding action of multiple dyneins into global beating. Our results demonstrate that an overall nonreciprocal beating pattern can emerge with time due to the spatial and temporal coordination of the individual dyneins. These findings provide insights in the fundamental working mechanism of axonemal dyneins and could possibly open new research directions in the field of flagellar motility.

Emergence of flagellar beating from the collective behavior of individual ATP-powered dyneins.

PubMed

Namdeo, S; Onck, P R

2016-10-01

Flagella are hair-like projections from the surface of eukaryotic cells, and they play an important role in many cellular functions, such as cell-motility. The beating of flagella is enabled by their internal architecture, the axoneme, and is powered by a dense distribution of motor proteins, dyneins. The dyneins deliver the required mechanical work through the hydrolysis of ATP. Although the dynein-ATP cycle, the axoneme microstructure, and the flagellar-beating kinematics are well studied, their integration into a coherent picture of ATP-powered flagellar beating is still lacking. Here we show that a time-delayed negative-work-based switching mechanism is able to convert the individual sliding action of hundreds of dyneins into a regular overall beating pattern leading to propulsion. We developed a computational model based on a minimal representation of the axoneme consisting of two representative doublet microtubules connected by nexin links. The relative sliding of the microtubules is incorporated by modeling two groups of ATP-powered dyneins, each responsible for sliding in opposite directions. A time-delayed switching mechanism is postulated, which is key in converting the local individual sliding action of multiple dyneins into global beating. Our results demonstrate that an overall nonreciprocal beating pattern can emerge with time due to the spatial and temporal coordination of the individual dyneins. These findings provide insights in the fundamental working mechanism of axonemal dyneins and could possibly open new research directions in the field of flagellar motility.

"Discoveries in Planetary Sciences": Slide Sets Highlighting New Advances for Astronomy Educators

NASA Astrophysics Data System (ADS)

Brain, D. A.; Schneider, N. M.; Beyer, R. A.

2010-12-01

Planetary science is a field that evolves rapidly, motivated by spacecraft mission results. Exciting new mission results are generally communicated rather quickly to the public in the form of press releases and news stories, but it can take several years for new advances to work their way into college textbooks. Yet it is important for students to have exposure to these new advances for a number of reasons. In some cases, new work renders older textbook knowledge incorrect or incomplete. In some cases, new discoveries make it possible to emphasize older textbook knowledge in a new way. In all cases, new advances provide exciting and accessible examples of the scientific process in action. To bridge the gap between textbooks and new advances in planetary sciences we have developed content on new discoveries for use by undergraduate instructors. Called 'Discoveries in Planetary Sciences', each new discovery is summarized in a 3-slide PowerPoint presentation. The first slide describes the discovery, the second slide discusses the underlying planetary science concepts, and the third presents the big picture implications of the discovery. A fourth slide includes links to associated press releases, images, and primary sources. This effort is generously sponsored by the Division for Planetary Sciences of the American Astronomical Society, and the slide sets are available at http://dps.aas.org/education/dpsdisc/. Sixteen slide sets have been released so far covering topics spanning all sub-disciplines of planetary science. Results from the following spacecraft missions have been highlighted: MESSENGER, the Spirit and Opportunity rovers, Cassini, LCROSS, EPOXI, Chandrayan, Mars Reconnaissance Orbiter, Mars Express, and Venus Express. Additionally, new results from Earth-orbiting and ground-based observing platforms and programs such as Hubble, Keck, IRTF, the Catalina Sky Survey, HARPS, MEarth, Spitzer, and amateur astronomers have been highlighted. 4-5 new slide sets are scheduled for release before December 2010. In this presentation we will discuss our motivation for this project, our implementation approach (from choosing topics to creating the slide sets, to getting them reviewed and released), and give examples of slide sets. We will present information in the form of web statistics on how many educators are using the slide sets, and which topics are most popular. We will also present feedback from educators who have used them in the classroom, and possible new directions for our activity.

Visual memory effects on intraoperator study design: determining a minimum time gap between case reviews to reduce recall bias.

PubMed

Campbell, W Scott; Talmon, Geoffrey A; Foster, Kirk W; Baker, John J; Smith, Lynette M; Hinrichs, Steven H

2015-03-01

The objective of this research was to determine test intervals between intraoperator case reviews to minimize the impact of recall. Three pathologists were presented with a group of 120 slides and subsequently challenged with a study set of 120 slides after 2-week and 4-week intervals. The challenge set consisted of 60 slides seen during the initial review and 60 slides previously unseen within the study. Pathologists rendered a diagnosis for each slide and indicated whether they recalled seeing the slide previously (yes/no). Two weeks after having been shown 60 cases from a challenge set of 120 cases, the pathologists correctly remembered 26, 22, and 24 cases or 40% overall. After 4 weeks, the pathologists correctly recalled 31% of cases previously seen. Pathologists were capable of recalling from memory cases seen previously at 2 and 4 weeks. Recall rates may be sufficiently high to affect intraobserver study design. Copyright© by the American Society for Clinical Pathology.

Slide Set: Reproducible image analysis and batch processing with ImageJ.

PubMed

Nanes, Benjamin A

2015-11-01

Most imaging studies in the biological sciences rely on analyses that are relatively simple. However, manual repetition of analysis tasks across multiple regions in many images can complicate even the simplest analysis, making record keeping difficult, increasing the potential for error, and limiting reproducibility. While fully automated solutions are necessary for very large data sets, they are sometimes impractical for the small- and medium-sized data sets common in biology. Here we present the Slide Set plugin for ImageJ, which provides a framework for reproducible image analysis and batch processing. Slide Set organizes data into tables, associating image files with regions of interest and other relevant information. Analysis commands are automatically repeated over each image in the data set, and multiple commands can be chained together for more complex analysis tasks. All analysis parameters are saved, ensuring transparency and reproducibility. Slide Set includes a variety of built-in analysis commands and can be easily extended to automate other ImageJ plugins, reducing the manual repetition of image analysis without the set-up effort or programming expertise required for a fully automated solution.

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

Lei, Hongzhuan; Lu, Zhiming; Vesselinov, Velimir Valentinov

These are slides from a presentation on identifying heterogeneities in subsurface environment using the level set method. The slides start with the motivation, then explain Level Set Method (LSM), the algorithms, some examples are given, and finally future work is explained.

Molecular mechanisms of microtubule-dependent kinetochore transport toward spindle poles

PubMed Central

Tanaka, Kozo; Kitamura, Etsushi; Kitamura, Yoko; Tanaka, Tomoyuki U.

2007-01-01

In mitosis, kinetochores are initially captured by the lateral sides of single microtubules and are subsequently transported toward spindle poles. Mechanisms for kinetochore transport are not yet known. We present two mechanisms involved in microtubule-dependent poleward kinetochore transport in Saccharomyces cerevisiae. First, kinetochores slide along the microtubule lateral surface, which is mainly and probably exclusively driven by Kar3, a kinesin-14 family member that localizes at kinetochores. Second, kinetochores are tethered at the microtubule distal ends and pulled poleward as microtubules shrink (end-on pulling). Kinetochore sliding is often converted to end-on pulling, enabling more processive transport, but the opposite conversion is rare. The establishment of end-on pulling is partly hindered by Kar3, and its progression requires the Dam1 complex. We suggest that the Dam1 complexes, which probably encircle a single microtubule, can convert microtubule depolymerization into the poleward kinetochore-pulling force. Thus, microtubule-dependent poleward kinetochore transport is ensured by at least two distinct mechanisms. PMID:17620411

Nanoscale wear and kinetic friction between atomically smooth surfaces sliding at high speeds

NASA Astrophysics Data System (ADS)

Rajauria, Sukumar; Canchi, Sripathi V.; Schreck, Erhard; Marchon, Bruno

2015-02-01

The kinetic friction and wear at high sliding speeds is investigated using the head-disk interface of hard disk drives, wherein the head and the disk are less than 10 nm apart and move at sliding speeds of 5-10 m/s relative to each other. While the spacing between the sliding surfaces is of the same order of magnitude as various AFM based fundamental studies on friction, the sliding speed is nearly six orders of magnitude larger, allowing a unique set-up for a systematic study of nanoscale wear at high sliding speeds. In a hard disk drive, the physical contact between the head and the disk leads to friction, wear, and degradation of the head overcoat material (typically diamond like carbon). In this work, strain gauge based friction measurements are performed; the friction coefficient as well as the adhering shear strength at the head-disk interface is extracted; and an experimental set-up for studying friction between high speed sliding surfaces is exemplified.

Stress relaxation at a gelatin hydrogel-glass interface in direct shear sliding

NASA Astrophysics Data System (ADS)

Gupta, Vinit; Singh, Arun K.

2018-01-01

In this paper, we study experimentally the stress relaxation behavior of soft solids such as gelatin hydrogels on a smooth glass surface in direct shear sliding. It is observed experimentally that irrespective of pulling velocity, the sliding block relaxes to the same level of nonzero residual stress. However, residual stress increases with increasing gelatin concentration in the hydrogels. We have also validated a friction model for strong bond formation during steady relaxation in light of the experimental observations. Our theoretical analysis establishes that population of dangling chains at the sliding interface significantly affects the relaxation process. As a result, residual stress increases with increasing gelatin concentration or decreasing mesh size of the three-dimensional structures in the hydrogels. It is also found that the transition time, at which a weak bond converts to strong bond, increases with increasing mesh size of the hydrogels. Moreover, relaxation time constant of a strong bond decreases with increasing mesh size. However, activation length of a strong bond increases with mesh size. Finally, this study signifies the role of residual strength in frictional shear sliding and it is believed that these results should be useful to understand the role of residual stress in stick-slip instability.

MOVES2014 at the Project Level for Experienced Users, October 2014 Webinar Slides

EPA Pesticide Factsheets

This webinar covers the changes that enhance the MOtor Vehicle Emission Simulator at the project scale, changes to its graphical user interface at the project scale, how to convert a MOVES2010b project-level input file to MOVES2014 format, and new input.

[Performance assessment employing slide sets: A tool for the classification of senior microscopists from Colombia´s Malaria Control Program].

PubMed

Mendoza, Nohora Marcela; González, Nohora Elizabeth

2015-01-01

One of the most important activities for quality assurance of malaria diagnosis is performance assessment. In Colombia, performance assessment of malaria microscopists has been done through the external performance assessment and indirect external performance assessment programs. To assess the performance of malaria microscopists of public reference laboratories using slide sets, and to describe the methodology used for this purpose. This was a retrospective study to evaluate the concordance of senior microscopists regarding parasite detection, species identification and parasite count based on the results of the assessment of competences using two sets, one comprising 40 slides, and another one with 17 slides. The concordance for parasite detection was 96.9% (95% CI: 96.0-97.5) and 88.7% (95% CI: 86.6-90.5) for species identification. The average percentage of concordant slides in the group evaluated was 89.7% (95% CI: 87.5-91.6). Most of the senior microscopists in Colombia were classified in the two top categories in the performance assessment using slide sets. The most common difficulty encountered was the identification of parasite species. The use of this tool to assess individual performance of microscopists in the evaluation of samples with different degrees of difficulty allows for characterizing the members of the malaria diagnosis network and strengthening the abilities of those who require it.

Transition of a dental histology course from light to virtual microscopy.

PubMed

Weaker, Frank J; Herbert, Damon C

2009-10-01

The transition of the dental histology course at the University of Texas Health Science Center at San Antonio Dental School was completed gradually over a five-year period. A pilot project was initially conducted to study the feasibility of integrating virtual microscopy into a traditional light microscopic lecture and laboratory course. Because of the difficulty of procuring quality calcified and decalcified sections of teeth, slides from the student loan collection in the oral histology block of the course were outsourced for conversion to digital images and placed on DVDs along with a slide viewer. The slide viewer mimicked the light microscope, allowing horizontal and vertical movement and changing of magnification, and, in addition, a feature to capture static images. In a survey, students rated the ease of use of the software, quality of the images, maneuverability of the images, and questions regarding use of the software, effective use of laboratory, and faculty time. Because of the positive support from the students, our entire student loan collection of 153 glass slides was subsequently converted to virtual images and distributed on an Apricorn pocket external hard drive. Students were asked to assess the virtual microscope over a four-year period. As a result of the surveys, light microscopes have been totally eliminated, and microscope exams have been replaced with project slide examinations. In the future, we plan to expand our virtual slides and incorporate computer testing.

The dynamic behaviour of data-driven Δ-M and ΔΣ-M in sliding mode control

NASA Astrophysics Data System (ADS)

Almakhles, Dhafer; Swain, Akshya K.; Nasiri, Alireza

2017-11-01

In recent years, delta (Δ-M) and delta-sigma modulators (ΔΣ-M) are increasingly being used as efficient data converters due to numerous advantages they offer. This paper investigates various dynamical features of these modulators/systems (both in continuous and discrete time domain) and derives their stability conditions using the theory of sliding mode. The upper bound of the hitting time (step) has been estimated. The equivalent mode conditions, i.e. where the outputs of the modulators are equivalent to the inputs, are established. The results of the analysis are validated through simulations considering a numerical example.

EPA activities related to emerging air sensor technology

EPA Science Inventory

This slide set was developed through contributions of NERL and NRMRL research groups and organized to explain the diversity of ongoing research related to emerging air sensor technology for an international audience. Gayle will be walking OAQPS through the slide set in advance o...

On-the-fly selection of cell-specific enhancers, genes, miRNAs and proteins across the human body using SlideBase

PubMed Central

Ienasescu, Hans; Li, Kang; Andersson, Robin; Vitezic, Morana; Rennie, Sarah; Chen, Yun; Vitting-Seerup, Kristoffer; Lagoni, Emil; Boyd, Mette; Bornholdt, Jette; de Hoon, Michiel J. L.; Kawaji, Hideya; Lassmann, Timo; Hayashizaki, Yoshihide; Forrest, Alistair R. R.; Carninci, Piero; Sandelin, Albin

2016-01-01

Genomics consortia have produced large datasets profiling the expression of genes, micro-RNAs, enhancers and more across human tissues or cells. There is a need for intuitive tools to select subsets of such data that is the most relevant for specific studies. To this end, we present SlideBase, a web tool which offers a new way of selecting genes, promoters, enhancers and microRNAs that are preferentially expressed/used in a specified set of cells/tissues, based on the use of interactive sliders. With the help of sliders, SlideBase enables users to define custom expression thresholds for individual cell types/tissues, producing sets of genes, enhancers etc. which satisfy these constraints. Changes in slider settings result in simultaneous changes in the selected sets, updated in real time. SlideBase is linked to major databases from genomics consortia, including FANTOM, GTEx, The Human Protein Atlas and BioGPS. Database URL: http://slidebase.binf.ku.dk PMID:28025337

Semantic focusing allows fully automated single-layer slide scanning of cervical cytology slides.

PubMed

Lahrmann, Bernd; Valous, Nektarios A; Eisenmann, Urs; Wentzensen, Nicolas; Grabe, Niels

2013-01-01

Liquid-based cytology (LBC) in conjunction with Whole-Slide Imaging (WSI) enables the objective and sensitive and quantitative evaluation of biomarkers in cytology. However, the complex three-dimensional distribution of cells on LBC slides requires manual focusing, long scanning-times, and multi-layer scanning. Here, we present a solution that overcomes these limitations in two steps: first, we make sure that focus points are only set on cells. Secondly, we check the total slide focus quality. From a first analysis we detected that superficial dust can be separated from the cell layer (thin layer of cells on the glass slide) itself. Then we analyzed 2,295 individual focus points from 51 LBC slides stained for p16 and Ki67. Using the number of edges in a focus point image, specific color values and size-inclusion filters, focus points detecting cells could be distinguished from focus points on artifacts (accuracy 98.6%). Sharpness as total focus quality of a virtual LBC slide is computed from 5 sharpness features. We trained a multi-parameter SVM classifier on 1,600 images. On an independent validation set of 3,232 cell images we achieved an accuracy of 94.8% for classifying images as focused. Our results show that single-layer scanning of LBC slides is possible and how it can be achieved. We assembled focus point analysis and sharpness classification into a fully automatic, iterative workflow, free of user intervention, which performs repetitive slide scanning as necessary. On 400 LBC slides we achieved a scanning-time of 13.9±10.1 min with 29.1±15.5 focus points. In summary, the integration of semantic focus information into whole-slide imaging allows automatic high-quality imaging of LBC slides and subsequent biomarker analysis.

Midwestern Medieval Illuminations Archives.

ERIC Educational Resources Information Center

Purdue Univ., Lafayette, IN. Audio-Visual Center.

This catalog lists the slides of medieval manuscript illuminations available at the Midwestern Medieval Illuminations Archives at the Purdue University Audio-Visual Center. Instructions are provided for ordering slides from the Center. Slide sets are listed by title, with citations including catalog number, rental price, producer/vendor code,…

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

Rajauria, Sukumar, E-mail: sukumar.rajauria@hgst.com; Canchi, Sripathi V., E-mail: sripathi.canchi@hgst.com; Schreck, Erhard

The kinetic friction and wear at high sliding speeds is investigated using the head-disk interface of hard disk drives, wherein the head and the disk are less than 10 nm apart and move at sliding speeds of 5–10 m/s relative to each other. While the spacing between the sliding surfaces is of the same order of magnitude as various AFM based fundamental studies on friction, the sliding speed is nearly six orders of magnitude larger, allowing a unique set-up for a systematic study of nanoscale wear at high sliding speeds. In a hard disk drive, the physical contact between the head andmore » the disk leads to friction, wear, and degradation of the head overcoat material (typically diamond like carbon). In this work, strain gauge based friction measurements are performed; the friction coefficient as well as the adhering shear strength at the head-disk interface is extracted; and an experimental set-up for studying friction between high speed sliding surfaces is exemplified.« less

Diagnostic Assessment of Deep Learning Algorithms for Detection of Lymph Node Metastases in Women With Breast Cancer.

PubMed

Ehteshami Bejnordi, Babak; Veta, Mitko; Johannes van Diest, Paul; van Ginneken, Bram; Karssemeijer, Nico; Litjens, Geert; van der Laak, Jeroen A W M; Hermsen, Meyke; Manson, Quirine F; Balkenhol, Maschenka; Geessink, Oscar; Stathonikos, Nikolaos; van Dijk, Marcory Crf; Bult, Peter; Beca, Francisco; Beck, Andrew H; Wang, Dayong; Khosla, Aditya; Gargeya, Rishab; Irshad, Humayun; Zhong, Aoxiao; Dou, Qi; Li, Quanzheng; Chen, Hao; Lin, Huang-Jing; Heng, Pheng-Ann; Haß, Christian; Bruni, Elia; Wong, Quincy; Halici, Ugur; Öner, Mustafa Ümit; Cetin-Atalay, Rengul; Berseth, Matt; Khvatkov, Vitali; Vylegzhanin, Alexei; Kraus, Oren; Shaban, Muhammad; Rajpoot, Nasir; Awan, Ruqayya; Sirinukunwattana, Korsuk; Qaiser, Talha; Tsang, Yee-Wah; Tellez, David; Annuscheit, Jonas; Hufnagl, Peter; Valkonen, Mira; Kartasalo, Kimmo; Latonen, Leena; Ruusuvuori, Pekka; Liimatainen, Kaisa; Albarqouni, Shadi; Mungal, Bharti; George, Ami; Demirci, Stefanie; Navab, Nassir; Watanabe, Seiryo; Seno, Shigeto; Takenaka, Yoichi; Matsuda, Hideo; Ahmady Phoulady, Hady; Kovalev, Vassili; Kalinovsky, Alexander; Liauchuk, Vitali; Bueno, Gloria; Fernandez-Carrobles, M Milagro; Serrano, Ismael; Deniz, Oscar; Racoceanu, Daniel; Venâncio, Rui

2017-12-12

Application of deep learning algorithms to whole-slide pathology images can potentially improve diagnostic accuracy and efficiency. Assess the performance of automated deep learning algorithms at detecting metastases in hematoxylin and eosin-stained tissue sections of lymph nodes of women with breast cancer and compare it with pathologists' diagnoses in a diagnostic setting. Researcher challenge competition (CAMELYON16) to develop automated solutions for detecting lymph node metastases (November 2015-November 2016). A training data set of whole-slide images from 2 centers in the Netherlands with (n = 110) and without (n = 160) nodal metastases verified by immunohistochemical staining were provided to challenge participants to build algorithms. Algorithm performance was evaluated in an independent test set of 129 whole-slide images (49 with and 80 without metastases). The same test set of corresponding glass slides was also evaluated by a panel of 11 pathologists with time constraint (WTC) from the Netherlands to ascertain likelihood of nodal metastases for each slide in a flexible 2-hour session, simulating routine pathology workflow, and by 1 pathologist without time constraint (WOTC). Deep learning algorithms submitted as part of a challenge competition or pathologist interpretation. The presence of specific metastatic foci and the absence vs presence of lymph node metastasis in a slide or image using receiver operating characteristic curve analysis. The 11 pathologists participating in the simulation exercise rated their diagnostic confidence as definitely normal, probably normal, equivocal, probably tumor, or definitely tumor. The area under the receiver operating characteristic curve (AUC) for the algorithms ranged from 0.556 to 0.994. The top-performing algorithm achieved a lesion-level, true-positive fraction comparable with that of the pathologist WOTC (72.4% [95% CI, 64.3%-80.4%]) at a mean of 0.0125 false-positives per normal whole-slide image. For the whole-slide image classification task, the best algorithm (AUC, 0.994 [95% CI, 0.983-0.999]) performed significantly better than the pathologists WTC in a diagnostic simulation (mean AUC, 0.810 [range, 0.738-0.884]; P < .001). The top 5 algorithms had a mean AUC that was comparable with the pathologist interpreting the slides in the absence of time constraints (mean AUC, 0.960 [range, 0.923-0.994] for the top 5 algorithms vs 0.966 [95% CI, 0.927-0.998] for the pathologist WOTC). In the setting of a challenge competition, some deep learning algorithms achieved better diagnostic performance than a panel of 11 pathologists participating in a simulation exercise designed to mimic routine pathology workflow; algorithm performance was comparable with an expert pathologist interpreting whole-slide images without time constraints. Whether this approach has clinical utility will require evaluation in a clinical setting.

Diagnostic Assessment of Deep Learning Algorithms for Detection of Lymph Node Metastases in Women With Breast Cancer

PubMed Central

Veta, Mitko; Johannes van Diest, Paul; van Ginneken, Bram; Karssemeijer, Nico; Litjens, Geert; van der Laak, Jeroen A. W. M.; Hermsen, Meyke; Manson, Quirine F; Balkenhol, Maschenka; Geessink, Oscar; Stathonikos, Nikolaos; van Dijk, Marcory CRF; Bult, Peter; Beca, Francisco; Beck, Andrew H; Wang, Dayong; Khosla, Aditya; Gargeya, Rishab; Irshad, Humayun; Zhong, Aoxiao; Dou, Qi; Li, Quanzheng; Chen, Hao; Lin, Huang-Jing; Heng, Pheng-Ann; Haß, Christian; Bruni, Elia; Wong, Quincy; Halici, Ugur; Öner, Mustafa Ümit; Cetin-Atalay, Rengul; Berseth, Matt; Khvatkov, Vitali; Vylegzhanin, Alexei; Kraus, Oren; Shaban, Muhammad; Rajpoot, Nasir; Awan, Ruqayya; Sirinukunwattana, Korsuk; Qaiser, Talha; Tsang, Yee-Wah; Tellez, David; Annuscheit, Jonas; Hufnagl, Peter; Valkonen, Mira; Kartasalo, Kimmo; Latonen, Leena; Ruusuvuori, Pekka; Liimatainen, Kaisa; Albarqouni, Shadi; Mungal, Bharti; George, Ami; Demirci, Stefanie; Navab, Nassir; Watanabe, Seiryo; Seno, Shigeto; Takenaka, Yoichi; Matsuda, Hideo; Ahmady Phoulady, Hady; Kovalev, Vassili; Kalinovsky, Alexander; Liauchuk, Vitali; Bueno, Gloria; Fernandez-Carrobles, M. Milagro; Serrano, Ismael; Deniz, Oscar; Racoceanu, Daniel; Venâncio, Rui

2017-01-01

Importance Application of deep learning algorithms to whole-slide pathology images can potentially improve diagnostic accuracy and efficiency. Objective Assess the performance of automated deep learning algorithms at detecting metastases in hematoxylin and eosin–stained tissue sections of lymph nodes of women with breast cancer and compare it with pathologists’ diagnoses in a diagnostic setting. Design, Setting, and Participants Researcher challenge competition (CAMELYON16) to develop automated solutions for detecting lymph node metastases (November 2015-November 2016). A training data set of whole-slide images from 2 centers in the Netherlands with (n = 110) and without (n = 160) nodal metastases verified by immunohistochemical staining were provided to challenge participants to build algorithms. Algorithm performance was evaluated in an independent test set of 129 whole-slide images (49 with and 80 without metastases). The same test set of corresponding glass slides was also evaluated by a panel of 11 pathologists with time constraint (WTC) from the Netherlands to ascertain likelihood of nodal metastases for each slide in a flexible 2-hour session, simulating routine pathology workflow, and by 1 pathologist without time constraint (WOTC). Exposures Deep learning algorithms submitted as part of a challenge competition or pathologist interpretation. Main Outcomes and Measures The presence of specific metastatic foci and the absence vs presence of lymph node metastasis in a slide or image using receiver operating characteristic curve analysis. The 11 pathologists participating in the simulation exercise rated their diagnostic confidence as definitely normal, probably normal, equivocal, probably tumor, or definitely tumor. Results The area under the receiver operating characteristic curve (AUC) for the algorithms ranged from 0.556 to 0.994. The top-performing algorithm achieved a lesion-level, true-positive fraction comparable with that of the pathologist WOTC (72.4% [95% CI, 64.3%-80.4%]) at a mean of 0.0125 false-positives per normal whole-slide image. For the whole-slide image classification task, the best algorithm (AUC, 0.994 [95% CI, 0.983-0.999]) performed significantly better than the pathologists WTC in a diagnostic simulation (mean AUC, 0.810 [range, 0.738-0.884]; P < .001). The top 5 algorithms had a mean AUC that was comparable with the pathologist interpreting the slides in the absence of time constraints (mean AUC, 0.960 [range, 0.923-0.994] for the top 5 algorithms vs 0.966 [95% CI, 0.927-0.998] for the pathologist WOTC). Conclusions and Relevance In the setting of a challenge competition, some deep learning algorithms achieved better diagnostic performance than a panel of 11 pathologists participating in a simulation exercise designed to mimic routine pathology workflow; algorithm performance was comparable with an expert pathologist interpreting whole-slide images without time constraints. Whether this approach has clinical utility will require evaluation in a clinical setting. PMID:29234806

A High-Resolution Tile-Based Approach for Classifying Biological Regions in Whole-Slide Histopathological Images

PubMed Central

Hoffman, R.A.; Kothari, S.; Phan, J.H.; Wang, M.D.

2016-01-01

Computational analysis of histopathological whole slide images (WSIs) has emerged as a potential means for improving cancer diagnosis and prognosis. However, an open issue relating to the automated processing of WSIs is the identification of biological regions such as tumor, stroma, and necrotic tissue on the slide. We develop a method for classifying WSI portions (512x512-pixel tiles) into biological regions by (1) extracting a set of 461 image features from each WSI tile, (2) optimizing tile-level prediction models using nested cross-validation on a small (600 tile) manually annotated tile-level training set, and (3) validating the models against a much larger (1.7x106 tile) data set for which ground truth was available on the whole-slide level. We calculated the predicted prevalence of each tissue region and compared this prevalence to the ground truth prevalence for each image in an independent validation set. Results show significant correlation between the predicted (using automated system) and reported biological region prevalences with p < 0.001 for eight of nine cases considered. PMID:27532012

A High-Resolution Tile-Based Approach for Classifying Biological Regions in Whole-Slide Histopathological Images.

PubMed

Hoffman, R A; Kothari, S; Phan, J H; Wang, M D

Computational analysis of histopathological whole slide images (WSIs) has emerged as a potential means for improving cancer diagnosis and prognosis. However, an open issue relating to the automated processing of WSIs is the identification of biological regions such as tumor, stroma, and necrotic tissue on the slide. We develop a method for classifying WSI portions (512x512-pixel tiles) into biological regions by (1) extracting a set of 461 image features from each WSI tile, (2) optimizing tile-level prediction models using nested cross-validation on a small (600 tile) manually annotated tile-level training set, and (3) validating the models against a much larger (1.7x10 6 tile) data set for which ground truth was available on the whole-slide level. We calculated the predicted prevalence of each tissue region and compared this prevalence to the ground truth prevalence for each image in an independent validation set. Results show significant correlation between the predicted (using automated system) and reported biological region prevalences with p < 0.001 for eight of nine cases considered.

Robust Stabilization of T-S Fuzzy Stochastic Descriptor Systems via Integral Sliding Modes.

PubMed

Li, Jinghao; Zhang, Qingling; Yan, Xing-Gang; Spurgeon, Sarah K

2017-09-19

This paper addresses the robust stabilization problem for T-S fuzzy stochastic descriptor systems using an integral sliding mode control paradigm. A classical integral sliding mode control scheme and a nonparallel distributed compensation (Non-PDC) integral sliding mode control scheme are presented. It is shown that two restrictive assumptions previously adopted developing sliding mode controllers for Takagi-Sugeno (T-S) fuzzy stochastic systems are not required with the proposed framework. A unified framework for sliding mode control of T-S fuzzy systems is formulated. The proposed Non-PDC integral sliding mode control scheme encompasses existing schemes when the previously imposed assumptions hold. Stability of the sliding motion is analyzed and the sliding mode controller is parameterized in terms of the solutions of a set of linear matrix inequalities which facilitates design. The methodology is applied to an inverted pendulum model to validate the effectiveness of the results presented.

Internally architectured materials with directionally asymmetric friction

PubMed Central

Bafekrpour, Ehsan; Dyskin, Arcady; Pasternak, Elena; Molotnikov, Andrey; Estrin, Yuri

2015-01-01

Internally Architectured Materials (IAMs) that exhibit different friction forces for sliding in the opposite directions are proposed. This is achieved by translating deformation normal to the sliding plane into a tangential force in a manner that is akin to a toothbrush with inclined bristles. Friction asymmetry is attained by employing a layered material or a structure with parallel ‘ribs’ inclined to the direction of sliding. A theory of directionally asymmetric friction is presented, along with prototype IAMs designed, fabricated and tested. The friction anisotropy (the ξ-coefficient) is characterised by the ratio of the friction forces for two opposite directions of sliding. It is further demonstrated that IAM can possess very high levels of friction anisotropy, with ξ of the order of 10. Further increase in ξ is attained by modifying the shape of the ribs to provide them with directionally dependent bending stiffness. Prototype IAMs produced by 3D printing exhibit truly giant friction asymmetry, with ξ in excess of 20. A novel mechanical rectifier, which can convert oscillatory movement into unidirectional movement by virtue of directionally asymmetric friction, is proposed. Possible applications include locomotion in a constrained environment and energy harvesting from oscillatory noise and vibrations. PMID:26040634

Field-programmable analogue arrays for the sensorless control of DC motors

NASA Astrophysics Data System (ADS)

Rivera, J.; Dueñas, I.; Ortega, S.; Del Valle, J. L.

2018-02-01

This work presents the analogue implementation of a sensorless controller for direct current motors based on the super-twisting (ST) sliding mode technique, by means of field programmable analogue arrays (FPAA). The novelty of this work is twofold, first is the use of the ST algorithm in a sensorless scheme for DC motors, and the implementation method of this type of sliding mode controllers in FPAAs. The ST algorithm reduces the chattering problem produced with the deliberate use of the sign function in classical sliding mode approaches. On the other hand, the advantages of the implementation method over a digital one are that the controller is not digitally approximated, the controller gains are not fine tuned and the implementation does not require the use of analogue-to-digital and digital-to-analogue converter circuits. In addition to this, the FPAA is a reconfigurable, lower cost and power consumption technology. Simulation and experimentation results were registered, where a more accurate transient response and lower power consumption were obtained by the proposed implementation method when compared to a digital implementation. Also, a more accurate performance by the DC motor is obtained with proposed sensorless ST technique when compared with a classical sliding mode approach.

Fully automated three-dimensional microscopy system

NASA Astrophysics Data System (ADS)

Kerschmann, Russell L.

2000-04-01

Tissue-scale structures such as vessel networks are imaged at micron resolution with the Virtual Tissue System (VT System). VT System imaging of cubic millimeters of tissue and other material extends the capabilities of conventional volumetric techniques such as confocal microscopy, and allows for the first time the integrated 2D and 3D analysis of important tissue structural relationships. The VT System eliminates the need for glass slide-mounted tissue sections and instead captures images directly from the surface of a block containing a sample. Tissues are en bloc stained with fluorochrome compounds, embedded in an optically conditioned polymer that suppresses image signals form dep within the block , and serially sectioned for imaging. Thousands of fully registered 2D images are automatically captured digitally to completely convert tissue samples into blocks of high-resolution information. The resulting multi gigabyte data sets constitute the raw material for precision visualization and analysis. Cellular function may be seen in a larger anatomical context. VT System technology makes tissue metrics, accurate cell enumeration and cell cycle analyses possible while preserving full histologic setting.

Towards better digital pathology workflows: programming libraries for high-speed sharpness assessment of Whole Slide Images.

PubMed

Ameisen, David; Deroulers, Christophe; Perrier, Valérie; Bouhidel, Fatiha; Battistella, Maxime; Legrès, Luc; Janin, Anne; Bertheau, Philippe; Yunès, Jean-Baptiste

2014-01-01

Since microscopic slides can now be automatically digitized and integrated in the clinical workflow, quality assessment of Whole Slide Images (WSI) has become a crucial issue. We present a no-reference quality assessment method that has been thoroughly tested since 2010 and is under implementation in multiple sites, both public university-hospitals and private entities. It is part of the FlexMIm R&D project which aims to improve the global workflow of digital pathology. For these uses, we have developed two programming libraries, in Java and Python, which can be integrated in various types of WSI acquisition systems, viewers and image analysis tools. Development and testing have been carried out on a MacBook Pro i7 and on a bi-Xeon 2.7GHz server. Libraries implementing the blur assessment method have been developed in Java, Python, PHP5 and MySQL5. For web applications, JavaScript, Ajax, JSON and Sockets were also used, as well as the Google Maps API. Aperio SVS files were converted into the Google Maps format using VIPS and Openslide libraries. We designed the Java library as a Service Provider Interface (SPI), extendable by third parties. Analysis is computed in real-time (3 billion pixels per minute). Tests were made on 5000 single images, 200 NDPI WSI, 100 Aperio SVS WSI converted to the Google Maps format. Applications based on our method and libraries can be used upstream, as calibration and quality control tool for the WSI acquisition systems, or as tools to reacquire tiles while the WSI is being scanned. They can also be used downstream to reacquire the complete slides that are below the quality threshold for surgical pathology analysis. WSI may also be displayed in a smarter way by sending and displaying the regions of highest quality before other regions. Such quality assessment scores could be integrated as WSI's metadata shared in clinical, research or teaching contexts, for a more efficient medical informatics workflow.

Tribology. Mechanisms of antiwear tribofilm growth revealed in situ by single-asperity sliding contacts.

PubMed

Gosvami, N N; Bares, J A; Mangolini, F; Konicek, A R; Yablon, D G; Carpick, R W

2015-04-03

Zinc dialkyldithiophosphates (ZDDPs) form antiwear tribofilms at sliding interfaces and are widely used as additives in automotive lubricants. The mechanisms governing the tribofilm growth are not well understood, which limits the development of replacements that offer better performance and are less likely to degrade automobile catalytic converters over time. Using atomic force microscopy in ZDDP-containing lubricant base stock at elevated temperatures, we monitored the growth and properties of the tribofilms in situ in well-defined single-asperity sliding nanocontacts. Surface-based nucleation, growth, and thickness saturation of patchy tribofilms were observed. The growth rate increased exponentially with either applied compressive stress or temperature, consistent with a thermally activated, stress-assisted reaction rate model. Although some models rely on the presence of iron to catalyze tribofilm growth, the films grew regardless of the presence of iron on either the tip or substrate, highlighting the critical role of stress and thermal activation. Copyright © 2015, American Association for the Advancement of Science.

Linear motor drive system for continuous-path closed-loop position control of an object

DOEpatents

Barkman, William E.

1980-01-01

A precision numerical controlled servo-positioning system is provided for continuous closed-loop position control of a machine slide or platform driven by a linear-induction motor. The system utilizes filtered velocity feedback to provide system stability required to operate with a system gain of 100 inches/minute/0.001 inch of following error. The filtered velocity feedback signal is derived from the position output signals of a laser interferometer utilized to monitor the movement of the slide. Air-bearing slides mounted to a stable support are utilized to minimize friction and small irregularities in the slideway which would tend to introduce positioning errors. A microprocessor is programmed to read command and feedback information and converts this information into the system following error signal. This error signal is summed with the negative filtered velocity feedback signal at the input of a servo amplifier whose output serves as the drive power signal to the linear motor position control coil.

Dynamics of solid lubrication as observed by optical microscopy

NASA Technical Reports Server (NTRS)

Sliney, H. E.

1976-01-01

A bench metallograph was converted into a micro contact imager by the addition of a tribometer employing a steel ball in sliding contact with a glass disk. The sliding contact was viewed in real time by means of projection microscope optics. The dynamics of abrasive particles and of solid lubricant particles within the contact were observed in detail. The contact was characterized by a constantly changing pattern of elastic strain with the passage of surface discontinuities and solid particles. Abrasive particles fragmented upon entering the contact, embedded in one surface and scratched the other; in contrast, the solid lubricant particles flowed plastically into thin films. The rheological behavior of the lubricating solids gave every appearance of a paste-like consistency within the Hertzian contact.

Adaptive Control for Buck Power Converter Using Fixed Point Inducting Control and Zero Average Dynamics Strategies

NASA Astrophysics Data System (ADS)

Hoyos Velasco, Fredy Edimer; García, Nicolás Toro; Garcés Gómez, Yeison Alberto

In this paper, the output voltage of a buck power converter is controlled by means of a quasi-sliding scheme. The Fixed Point Inducting Control (FPIC) technique is used for the control design, based on the Zero Average Dynamics (ZAD) strategy, including load estimation by means of the Least Mean Squares (LMS) method. The control scheme is tested in a Rapid Control Prototyping (RCP) system based on Digital Signal Processing (DSP) for dSPACE platform. The closed loop system shows adequate performance. The experimental and simulation results match. The main contribution of this paper is to introduce the load estimator by means of LMS, to make ZAD and FPIC control feasible in load variation conditions. In addition, comparison results for controlled buck converter with SMC, PID and ZAD-FPIC control techniques are shown.

Digital and traditional slides for teaching cellular morphology: a comparative analysis of learning outcomes.

PubMed

Solberg, Brooke L

2012-01-01

Recent advances in technology have brought forth an intriguing new tool for teaching hematopoietic cellular identification skills: the digital slide. Although digitized slides offer a number of appealing options for educators, little research has been done to examine how their utilization would impact learning outcomes. To fill that void, this study was designed to examine student performance, skill retention and transferability, and self-efficacy beliefs amongst undergraduate MLS students learning cellular morphology with digital versus traditional slides. Results showed that students learning with digital slides performed better on assessments containing only traditional slide specimens than students learning with traditional slides, both immediately following the learning activity and after a considerable duration of time. Students learning with digital slides also reported slightly higher levels of self-efficacy related to cellular identification. The findings of this study suggest that students learning cellular identification skills with digital slides are able to transfer that skill directly to traditional slides, and that their ability to identify cells is not negatively affected in present or future settings.

Rock Slide Risk Assessment: A Semi-Quantitative Approach

NASA Astrophysics Data System (ADS)

Duzgun, H. S. B.

2009-04-01

Rock slides can be better managed by systematic risk assessments. Any risk assessment methodology for rock slides involves identification of rock slide risk components, which are hazard, elements at risk and vulnerability. For a quantitative/semi-quantitative risk assessment for rock slides, a mathematical value the risk has to be computed and evaluated. The quantitative evaluation of risk for rock slides enables comparison of the computed risk with the risk of other natural and/or human-made hazards and providing better decision support and easier communication for the decision makers. A quantitative/semi-quantitative risk assessment procedure involves: Danger Identification, Hazard Assessment, Elements at Risk Identification, Vulnerability Assessment, Risk computation, Risk Evaluation. On the other hand, the steps of this procedure require adaptation of existing or development of new implementation methods depending on the type of landslide, data availability, investigation scale and nature of consequences. In study, a generic semi-quantitative risk assessment (SQRA) procedure for rock slides is proposed. The procedure has five consecutive stages: Data collection and analyses, hazard assessment, analyses of elements at risk and vulnerability and risk assessment. The implementation of the procedure for a single rock slide case is illustrated for a rock slope in Norway. Rock slides from mountain Ramnefjell to lake Loen are considered to be one of the major geohazards in Norway. Lake Loen is located in the inner part of Nordfjord in Western Norway. Ramnefjell Mountain is heavily jointed leading to formation of vertical rock slices with height between 400-450 m and width between 7-10 m. These slices threaten the settlements around Loen Valley and tourists visiting the fjord during summer season, as the released slides have potential of creating tsunami. In the past, several rock slides had been recorded from the Mountain Ramnefjell between 1905 and 1950. Among them, four of the slides caused formation of tsunami waves which washed up to 74 m above the lake level. Two of the slides resulted in many fatalities in the inner part of the Loen Valley as well as great damages. There are three predominant joint structures in Ramnefjell Mountain, which controls failure and the geometry of the slides. The first joint set is a foliation plane striking northeast-southwest and dipping 35˚ -40˚ to the east-southeast. The second and the third joint sets are almost perpendicular and parallel to the mountain side and scarp, respectively. These three joint sets form slices of rock columns with width ranging between 7-10 m and height of 400-450 m. It is stated that the joints in set II are opened between 1-2 m, which may bring about collection of water during heavy rainfall or snow melt causing the slices to be pressed out. It is estimated that water in the vertical joints both reduces the shear strength of sliding plane and causes reduction of normal stress on the sliding plane due to formation of uplift force. Hence rock slides in Ramnefjell mountain occur in plane failure mode. The quantitative evaluation of rock slide risk requires probabilistic analysis of rock slope stability and identification of consequences if the rock slide occurs. In this study failure probability of a rock slice is evaluated by first-order reliability method (FORM). Then in order to use the calculated probability of failure value (Pf) in risk analyses, it is required to associate this Pf with frequency based probabilities (i.ePf / year) since the computed failure probabilities is a measure of hazard and not a measure of risk unless they are associated with the consequences of the failure. This can be done by either considering the time dependent behavior of the basic variables in the probabilistic models or associating the computed Pf with frequency of the failures in the region. In this study, the frequency of previous rock slides in the previous century in Remnefjell is used for evaluation of frequency based probability to be used in risk assessment. The major consequence of a rock slide is generation of a tsunami in the lake Loen, causing inundation of residential areas around the lake. Risk is assessed by adapting damage probability matrix approach, which is originally developed for risk assessment for buildings in case of earthquake.

Rapid Preliminary Design of Interplanetary Trajectories Using the Evolutionary Mission Trajectory Generator

NASA Technical Reports Server (NTRS)

Englander, Jacob

2016-01-01

This set of tutorial slides is an introduction to the Evolutionary Mission Trajectory Generator (EMTG), NASA Goddard Space Flight Center's autonomous tool for preliminary design of interplanetary missions. This slide set covers the basics of creating and post-processing simple interplanetary missions in EMTG using both high-thrust chemical and low-thrust electric propulsion along with a variety of operational constraints.

Consider the Soil First. Narrative Guide for Color Slide Set and Film Strip C-183.

ERIC Educational Resources Information Center

Soil Conservation Service (USDA), Washington, DC.

The importance of soil, its use and suitability for agriculture and building construction, and the need for and value of soil surveys are emphasized in this pamphlet. It serves as the script for a set of color slides and filmstrip produced by the Soil Conservation Service, U.S. Department of Agriculture. Each of the 73 frames is illustrated with…

Active Learning: A Small Group Histology Laboratory Exercise in a Whole Class Setting Utilizing Virtual Slides and Peer Education

ERIC Educational Resources Information Center

Bloodgood, Robert A.

2012-01-01

Histology laboratory instruction is moving away from the sole use of the traditional combination of light microscopes and glass slides in favor of virtual microscopy and virtual slides. At the same time, medical curricula are changing so as to reduce scheduled time for basic science instruction as well as focusing on student-centered learning…

Carolyn Stern Grant - Home Page

Science.gov Websites

;New Windows on the Universe", a slide set of 175 slides of different astronomical objects in different wavelengths, which I did with Christine Jones and Bill Forman. I have also done a lot of work with

16 CFR 1207.1 - Scope, purpose, and findings.

Code of Federal Regulations, 2012 CFR

2012-01-01

... Fifth Circuit set aside portions of that standard (Aqua Slide ‘N’ Drive Corporation v. CPSC, 569 F.2d... materials of manufacture or structural characteristics of the slides. It is estimated that 350,000 of these...

16 CFR 1207.1 - Scope, purpose, and findings.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Fifth Circuit set aside portions of that standard (Aqua Slide ‘N’ Drive Corporation v. CPSC, 569 F.2d... materials of manufacture or structural characteristics of the slides. It is estimated that 350,000 of these...

16 CFR 1207.1 - Scope, purpose, and findings.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Fifth Circuit set aside portions of that standard (Aqua Slide ‘N’ Drive Corporation v. CPSC, 569 F.2d... materials of manufacture or structural characteristics of the slides. It is estimated that 350,000 of these...

Development of a teledermatopathology consultation system using virtual slides

PubMed Central

2012-01-01

Background An online consultation system using virtual slides (whole slide images; WSI) has been developed for pathological diagnosis, and could help compensate for the shortage of pathologists, especially in the field of dermatopathology and in other fields dealing with difficult cases. This study focused on the performance and future potential of the system. Method In our system, histological specimens on slide glasses are digitalized by a virtual slide instrument, converted into web data, and up-loaded to an open server. Using our own purpose-built online system, we then input patient details such as age, gender, affected region, clinical data, past history and other related items. We next select up to ten consultants. Finally we send an e-mail to all consultants simultaneously through a single command. The consultant receives an e-mail containing an ID and password which is used to access the open server and inspect the images and other data associated with the case. The consultant makes a diagnosis, which is sent to us along with comments. Because this was a pilot study, we also conducted several questionnaires with consultants concerning the quality of images, operability, usability, and other issues. Results We solicited consultations for 36 cases, including cases of tumor, and involving one to eight consultants in the field of dermatopathology. No problems were noted concerning the images or the functioning of the system on the sender or receiver sides. The quickest diagnosis was received only 18 minutes after sending our data. This is much faster than in conventional consultation using glass slides. There were no major problems relating to the diagnosis, although there were some minor differences of opinion between consultants. The results of questionnaires answered by many consultants confirmed the usability of this system for pathological consultation. (16 out of 23 consultants.) Conclusion We have developed a novel teledermatopathological consultation system using virtual slides, and investigated the usefulness of the system. The results demonstrate that our system can be a useful tool for international medical work, and we anticipate its wider application in the future. Virtual slides The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1902376044831574 PMID:23237667

Sliding-Mode Control Applied for Robust Control of a Highly Unstable Aircraft

NASA Technical Reports Server (NTRS)

Vetter, Travis Kenneth

2002-01-01

An investigation into the application of an observer based sliding mode controller for robust control of a highly unstable aircraft and methods of compensating for actuator dynamics is performed. After a brief overview of some reconfigurable controllers, sliding mode control (SMC) is selected because of its invariance properties and lack of need for parameter identification. SMC is reviewed and issues with parasitic dynamics, which cause system instability, are addressed. Utilizing sliding manifold boundary layers, the nonlinear control is converted to a linear control and sliding manifold design is performed in the frequency domain. An additional feedback form of model reference hedging is employed which is similar to a prefilter and has large benefits to system performance. The effects of inclusion of actuator dynamics into the designed plant is heavily investigated. Multiple Simulink models of the full longitudinal dynamics and wing deflection modes of the forward swept aero elastic vehicle (FSAV) are constructed. Additionally a linear state space models to analyze effects from various system parameters. The FSAV has a pole at +7 rad/sec and is non-minimum phase. The use of 'model actuators' in the feedback path, and varying there design, is heavily investigated for the resulting effects on plant robustness and tolerance to actuator failure. The use of redundant actuators is also explored and improved robustness is shown. All models are simulated with severe failure and excellent tracking, and task dependent handling qualities, and low pilot induced oscillation tendency is shown.

Preliminary study of head-up assessment techniques. 1: Viewing duration of instrument panel and HUD symbology using a recall methodology

NASA Technical Reports Server (NTRS)

Haines, R. F.

1978-01-01

Eight commercial pilots were shown 50 colored, high fidelity slides of a standard instrument panel (IP) with the needle positions of each instrument varying from slide to slide and then 50 slides of a head-up display (HUD) symbology format which contained an equivalent amount of flight-related information as the instrument panel slides. All stimuli were presented under controlled, static viewing conditions that allowed the measurement of the speed and accuracy with which one randomly selected flight parameter on each slide could be read. The subject did not know which parameter would be requested and, therefore, had to remember the total set of information in order to answer the question correctly. The results showed that from 6.6 - 8.7 sec total viewing time was required to correctly extract altitude, airspeed, heading, VSI, or ADI from the IP slides and from 6.1 to 7.4 sec for the HUD slides.

Method and system for ultra-precision positioning

DOEpatents

Montesanti, Richard C.; Locke, Stanley F.; Thompson, Samuel L.

2005-01-11

An apparatus and method is disclosed for ultra-precision positioning. A slide base provides a foundational support. A slide plate moves with respect to the slide base along a first geometric axis. Either a ball-screw or a piezoelectric actuator working separate or in conjunction displaces the slide plate with respect to the slide base along the first geometric axis. A linking device directs a primary force vector into a center-line of the ball-screw. The linking device consists of a first link which directs a first portion of the primary force vector to an apex point, located along the center-line of the ball-screw, and a second link for directing a second portion of the primary force vector to the apex point. A set of rails, oriented substantially parallel to the center-line of the ball-screw, direct movement of the slide plate with respect to the slide base along the first geometric axis and are positioned such that the apex point falls within a geometric plane formed by the rails. The slide base, the slide plate, the ball-screw, and the linking device together form a slide assembly. Multiple slide assemblies can be distributed about a platform. In such a configuration, the platform may be raised and lowered, or tipped and tilted by jointly or independently displacing the slide plates.

Ultra-precision positioning assembly

DOEpatents

Montesanti, Richard C.; Locke, Stanley F.; Thompson, Samuel L.

2002-01-01

An apparatus and method is disclosed for ultra-precision positioning. A slide base provides a foundational support. A slide plate moves with respect to the slide base along a first geometric axis. Either a ball-screw or a piezoelectric actuator working separate or in conjunction displaces the slide plate with respect to the slide base along the first geometric axis. A linking device directs a primary force vector into a center-line of the ball-screw. The linking device consists of a first link which directs a first portion of the primary force vector to an apex point, located along the center-line of the ball-screw, and a second link for directing a second portion of the primary force vector to the apex point. A set of rails, oriented substantially parallel to the center-line of the ball-screw, direct movement of the slide plate with respect to the slide base along the first geometric axis and are positioned such that the apex point falls within a geometric plane formed by the rails. The slide base, the slide plate, the ball-screw, and the linking device together form a slide assembly. Multiple slide assemblies can be distributed about a platform. In such a configuration, the platform may be raised and lowered, or tipped and tilted by jointly or independently displacing the slide plates.

Studies with Laser Cooled Atoms and Single Molecules

DTIC Science & Technology

2007-09-01

between soda lime glass slides. The bond-setting time can be tailored to allow time for precision optical alignment. We also extended our previous single...This method achieves 100% successful bonding rates between soda lime glass slides. The bond-setting time and be can tailored to allow time for...simple method to bond optical components using silica nanoparticle sol-gel chemistry. The silica nanoparticles polymerize into highly branched

Sliding temperatures of ice skates

NASA Astrophysics Data System (ADS)

Colbeck, S. C.; Najarian, L.; Smith, H. B.

1997-06-01

The two theories developed to explain the low friction of ice, pressure melting and frictional heating, require opposite temperature shifts at the ice-skate interface. The arguments against pressure melting are strong, but only theoretical. A set of direct temperature measurements shows that frictional heating is the dominant mechanism because temperature behaves in the manner predicted by the theory of frictional heating. Like snow skis, ice skates are warmed by sliding and then cool when the sliding stops. The temperature increases with speed and with thermal insulation. The sliding leaves a warm track on the ice surface behind the skate and the skate sprays warm ejecta.

Towards better digital pathology workflows: programming libraries for high-speed sharpness assessment of Whole Slide Images

PubMed Central

2014-01-01

Background Since microscopic slides can now be automatically digitized and integrated in the clinical workflow, quality assessment of Whole Slide Images (WSI) has become a crucial issue. We present a no-reference quality assessment method that has been thoroughly tested since 2010 and is under implementation in multiple sites, both public university-hospitals and private entities. It is part of the FlexMIm R&D project which aims to improve the global workflow of digital pathology. For these uses, we have developed two programming libraries, in Java and Python, which can be integrated in various types of WSI acquisition systems, viewers and image analysis tools. Methods Development and testing have been carried out on a MacBook Pro i7 and on a bi-Xeon 2.7GHz server. Libraries implementing the blur assessment method have been developed in Java, Python, PHP5 and MySQL5. For web applications, JavaScript, Ajax, JSON and Sockets were also used, as well as the Google Maps API. Aperio SVS files were converted into the Google Maps format using VIPS and Openslide libraries. Results We designed the Java library as a Service Provider Interface (SPI), extendable by third parties. Analysis is computed in real-time (3 billion pixels per minute). Tests were made on 5000 single images, 200 NDPI WSI, 100 Aperio SVS WSI converted to the Google Maps format. Conclusions Applications based on our method and libraries can be used upstream, as calibration and quality control tool for the WSI acquisition systems, or as tools to reacquire tiles while the WSI is being scanned. They can also be used downstream to reacquire the complete slides that are below the quality threshold for surgical pathology analysis. WSI may also be displayed in a smarter way by sending and displaying the regions of highest quality before other regions. Such quality assessment scores could be integrated as WSI's metadata shared in clinical, research or teaching contexts, for a more efficient medical informatics workflow. PMID:25565494

Evaluating the visibility of presentation slides

NASA Astrophysics Data System (ADS)

Sugawara, Genki; Umezu, Nobuyuki

2017-03-01

Presentations using slide software such as PowerPoint are widely performed in offices and schools. The improvement of presentation skills among ordinary people is required because these days such an opportunity of giving presentation is becoming so common. One of the key factors for making successful presentation is the visibility of the slides, as well as the contents themselves. We propose an algorithm to numerically evaluate the visibility of presentation slides. Our method receives a presentation as a set of images and eliminates the background from the slides to extract characters and figures. This algorithm then evaluates the visibility according to the number and size of characters, their colors, and figure layouts. The slide evaluation criteria are based on the series of experiments with 20 participants to parameterize typical values for visual elements in slides. The algorithm is implemented on an iMac and takes 0.5 sec. to evaluate a slide image. The evaluation score is given as a value between 0 and 100 and the users can improve their slide pages with lower scores. Our future work includes a series of experiments with various presentations and extending our method to publish as a web-based rating service for learning presentation skills.

RecutClub.com: An Open Source, Whole Slide Image-based Pathology Education System

PubMed Central

Christensen, Paul A.; Lee, Nathan E.; Thrall, Michael J.; Powell, Suzanne Z.; Chevez-Barrios, Patricia; Long, S. Wesley

2017-01-01

Background: Our institution's pathology unknown conferences provide educational cases for our residents. However, the cases have not been previously available digitally, have not been collated for postconference review, and were not accessible to a wider audience. Our objective was to create an inexpensive whole slide image (WSI) education suite to address these limitations and improve the education of pathology trainees. Materials and Methods: We surveyed residents regarding their preference between four unique WSI systems. We then scanned weekly unknown conference cases and study set cases and uploaded them to our custom built WSI viewer located at RecutClub.com. We measured site utilization and conference participation. Results: Residents preferred our OpenLayers WSI implementation to Ventana Virtuoso, Google Maps API, and OpenSlide. Over 16 months, we uploaded 1366 cases from 77 conferences and ten study sets, occupying 793.5 GB of cloud storage. Based on resident evaluations, the interface was easy to use and demonstrated minimal latency. Residents are able to review cases from home and from their mobile devices. Worldwide, 955 unique IP addresses from 52 countries have viewed cases in our site. Conclusions: We implemented a low-cost, publicly available repository of WSI slides for resident education. Our trainees are very satisfied with the freedom to preview either the glass slides or WSI and review the WSI postconference. Both local users and worldwide users actively and repeatedly view cases in our study set. PMID:28382224

A technigue exploitation about anti-slide tire polyploid on ice-snow road in winter

NASA Astrophysics Data System (ADS)

Xiaojie, Qi; Qiang, Wang; Zhao, Yang; Yunlong, Wang; Guotian, Wang; Degang, Lv

2017-04-01

Present studies focus on improving anti-slide property of tyes on ice-snow road by changing material modification of tyre tread and designing groove. However, the basic reason causing starting slide, long braking distance, turning slide slip and so on of tyres used in winter is that tyre tread materials are unitary and homogenous rubber composite which can’t coordinate driving demands of tyres in winter under muti-work condition, and can’t exert their best property when starting, braking and sliding slip. In order to improve comprehensive anti-slide property of tyres, this paper discusses about changing structure, shape and distribution proportion among haploid materials of tyre tread rubber. Polyploid bubber tyre tread technique based on artificial neural network which is in favor of starting, braking and anti-slide slip is optimized and combined. Friction feature and anti-slide mechanism on ice-snow road of polyploid rubber tyre tread are studied using testing technique of low-temperature cabin and computer simulation. A set high anti-slide theories and realizing method systems of polyploid rubber composite formed from basic theory, models and technique method are developped which will be applied into solving anti-slide problem of winter tyres, provide theory instruction for studies on high anti-slide winter tyres, and promote development of application and usage safety of winter tyres.

Carnegie Mellon University bioimaging day 2014: Challenges and opportunities in digital pathology

PubMed Central

Rohde, Gustavo K.; Ozolek, John A.; Parwani, Anil V.; Pantanowitz, Liron

2014-01-01

Recent advances in digital imaging is impacting the practice of pathology. One of the key enabling technologies that is leading the way towards this transformation is the use of whole slide imaging (WSI) which allows glass slides to be converted into large image files that can be shared, stored, and analyzed rapidly. Many applications around this novel technology have evolved in the last decade including education, research and clinical applications. This publication highlights a collection of abstracts, each corresponding to a talk given at Carnegie Mellon University's (CMU) Bioimaging Day 2014 co-sponsored by the Biomedical Engineering and Lane Center for Computational Biology Departments at CMU. Topics related specifically to digital pathology are presented in this collection of abstracts. These include topics related to digital workflow implementation, imaging and artifacts, storage demands, and automated image analysis algorithms. PMID:25250190

Carnegie Mellon University bioimaging day 2014: Challenges and opportunities in digital pathology.

PubMed

Rohde, Gustavo K; Ozolek, John A; Parwani, Anil V; Pantanowitz, Liron

2014-01-01

Recent advances in digital imaging is impacting the practice of pathology. One of the key enabling technologies that is leading the way towards this transformation is the use of whole slide imaging (WSI) which allows glass slides to be converted into large image files that can be shared, stored, and analyzed rapidly. Many applications around this novel technology have evolved in the last decade including education, research and clinical applications. This publication highlights a collection of abstracts, each corresponding to a talk given at Carnegie Mellon University's (CMU) Bioimaging Day 2014 co-sponsored by the Biomedical Engineering and Lane Center for Computational Biology Departments at CMU. Topics related specifically to digital pathology are presented in this collection of abstracts. These include topics related to digital workflow implementation, imaging and artifacts, storage demands, and automated image analysis algorithms.

Image microarrays (IMA): Digital pathology's missing tool

PubMed Central

Hipp, Jason; Cheng, Jerome; Pantanowitz, Liron; Hewitt, Stephen; Yagi, Yukako; Monaco, James; Madabhushi, Anant; Rodriguez-canales, Jaime; Hanson, Jeffrey; Roy-Chowdhuri, Sinchita; Filie, Armando C.; Feldman, Michael D.; Tomaszewski, John E.; Shih, Natalie NC.; Brodsky, Victor; Giaccone, Giuseppe; Emmert-Buck, Michael R.; Balis, Ulysses J.

2011-01-01

Introduction: The increasing availability of whole slide imaging (WSI) data sets (digital slides) from glass slides offers new opportunities for the development of computer-aided diagnostic (CAD) algorithms. With the all-digital pathology workflow that these data sets will enable in the near future, literally millions of digital slides will be generated and stored. Consequently, the field in general and pathologists, specifically, will need tools to help extract actionable information from this new and vast collective repository. Methods: To address this limitation, we designed and implemented a tool (dCORE) to enable the systematic capture of image tiles with constrained size and resolution that contain desired histopathologic features. Results: In this communication, we describe a user-friendly tool that will enable pathologists to mine digital slides archives to create image microarrays (IMAs). IMAs are to digital slides as tissue microarrays (TMAs) are to cell blocks. Thus, a single digital slide could be transformed into an array of hundreds to thousands of high quality digital images, with each containing key diagnostic morphologies and appropriate controls. Current manual digital image cut-and-paste methods that allow for the creation of a grid of images (such as an IMA) of matching resolutions are tedious. Conclusion: The ability to create IMAs representing hundreds to thousands of vetted morphologic features has numerous applications in education, proficiency testing, consensus case review, and research. Lastly, in a manner analogous to the way conventional TMA technology has significantly accelerated in situ studies of tissue specimens use of IMAs has similar potential to significantly accelerate CAD algorithm development. PMID:22200030

Screwworm Eradication Data System (SEDS) applications program documentation, part 2

NASA Technical Reports Server (NTRS)

1976-01-01

National Oceanic and Atmospheric Administration (NOAA) satellite data, which is in analog tape form, is converted into output data products. These products are used by investigators in determining optimum areas for airdrops of steril screwworm flies over Mexico. The output product of SEDS takes the form of imagery data film slides showing Mexico and the lower southwest portion of the United States. The area analog preprocessing phase of the SEDS task is covered.

A Failure to Communicate

PubMed Central

Kronert, William A.; Melkani, Girish C.; Melkani, Anju; Bernstein, Sanford I.

2015-01-01

Our molecular modeling studies suggest a charge-dependent interaction between residues Glu-497 in the relay domain and Arg-712 in the converter domain of human β-cardiac myosin. To test the significance of this putative interaction, we generated transgenic Drosophila expressing indirect flight muscle myosin with charge reversal mutations in the relay (E496R) or converter (R713E). Each mutation yielded dramatic reductions in myosin Ca-ATPase activity (∼80%) as well as in basal (∼67%) and actin-activated (∼84%) Mg-ATPase activity. E496R myosin-induced in vitro actin-sliding velocity was reduced by 71% and R713E myosin permitted no actin motility. Indirect flight muscles of late pupae from each mutant displayed disrupted myofibril assembly, with adults having severely abnormal myofibrils and no flight ability. To understand the molecular basis of these defects, we constructed a putative compensatory mutant that expresses myosin with both E496R and R713E. Intriguingly, ATPase values were restored to ∼73% of wild-type and actin-sliding velocity increased to 40%. The double mutation suppresses myofibril assembly defects in pupal indirect flight muscles and dramatically reduces myofibril disruption in young adults. Although sarcomere organization is not sustained in older flies and flight ability is not restored in homozygotes, young heterozygotes fly well. Our results indicate that this charge-dependent interaction between the myosin relay and converter domains is essential to the mechanochemical cycle and sarcomere assembly. Furthermore, the same inter-domain interaction is disrupted when modeling human β-cardiac myosin heavy chain cardiomyopathy mutations E497D or R712L, implying that abolishing this salt bridge is one cause of the human disease. PMID:26446785

Photographing the Night Sky (Without a Telescope).

ERIC Educational Resources Information Center

Scott, Roger L.

1983-01-01

Describes the use of a 35-millimeter camera with color slide film to produce photographs of constellations, star trails, bright comets, aurorae, and meteor showers. Discusses film speed, lenses, f-stop settings, exposure times, and other items related to astrophotographic technique; provides ideas for use of slides in the classroom. (JM)

Convergence analysis of sliding mode trajectories in multi-objective neural networks learning.

PubMed

Costa, Marcelo Azevedo; Braga, Antonio Padua; de Menezes, Benjamin Rodrigues

2012-09-01

The Pareto-optimality concept is used in this paper in order to represent a constrained set of solutions that are able to trade-off the two main objective functions involved in neural networks supervised learning: data-set error and network complexity. The neural network is described as a dynamic system having error and complexity as its state variables and learning is presented as a process of controlling a learning trajectory in the resulting state space. In order to control the trajectories, sliding mode dynamics is imposed to the network. It is shown that arbitrary learning trajectories can be achieved by maintaining the sliding mode gains within their convergence intervals. Formal proofs of convergence conditions are therefore presented. The concept of trajectory learning presented in this paper goes further beyond the selection of a final state in the Pareto set, since it can be reached through different trajectories and states in the trajectory can be assessed individually against an additional objective function. Copyright © 2012 Elsevier Ltd. All rights reserved.

A rolling-sliding bench test for investigating rear axle lubrication

DOE PAGES

Stump, Benjamin C.; Zhou, Yan; Viola, Michael B.; ...

2018-02-07

An automotive rear axle is composed of a set of hypoid gears, whose contact surfaces experience a complex combination of rolling contact fatigue damage and sliding wear. Full-scale rear axle dynamometer tests are used in the industry for efficiency and durability assessment. Here, this study developed a bench-scale rolling-sliding test protocol by simulating the contact pressure, oil temperature, and lubrication regime experienced in a dynamometer duty cycle test. Initial bench results have demonstrated the ability of generating both rolling contact-induced micropitting and sliding wear and the feasibility of investigating the impact of slide-to-roll ratio, surface roughness, test duration, and oilmore » temperature on the friction behavior, vibration noise, and surface damage. Finally, this bench test will allow studying candidate rear axle lubricants and materials under relevant conditions.« less

A rolling-sliding bench test for investigating rear axle lubrication

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

Stump, Benjamin C.; Zhou, Yan; Viola, Michael B.

An automotive rear axle is composed of a set of hypoid gears, whose contact surfaces experience a complex combination of rolling contact fatigue damage and sliding wear. Full-scale rear axle dynamometer tests are used in the industry for efficiency and durability assessment. Here, this study developed a bench-scale rolling-sliding test protocol by simulating the contact pressure, oil temperature, and lubrication regime experienced in a dynamometer duty cycle test. Initial bench results have demonstrated the ability of generating both rolling contact-induced micropitting and sliding wear and the feasibility of investigating the impact of slide-to-roll ratio, surface roughness, test duration, and oilmore » temperature on the friction behavior, vibration noise, and surface damage. Finally, this bench test will allow studying candidate rear axle lubricants and materials under relevant conditions.« less

A Day in the Life of an Industrial Hearing Conservationist: A Template for Successful Career Education and Outreach Presentations

NASA Technical Reports Server (NTRS)

Cooper, Beth A.

1997-01-01

Whether in a classroom setting or at a local community meeting, opportunities for providing descriptive and positive information about our professions to an audience unfamiliar with acoustics, noise control or hearing conservation often call for alternatives to technical demonstrations that illustrate principles of acoustics or noise control. More importantly, successful outreach presentations must convey images of our day-to-day activities and the challenges we address, many of which are non-technical. One successful approach to career outreach presentations makes use of a collection of photo slides featuring the speaker, his colleagues, customers and workplaces to vividly illustrate the specific job tasks, people and environment of the speaker's job or career. Against this fluid and multi-dimensional visual backdrop, an accompanying script addresses the main theme. A comprehensive photo slide collection may be established gradually, often by making use of and adding to technical and personal slides already in the speaker's possession. Slide collections are portable, easily and quickly reconfigured for back-to-back or spontaneous engagements, and they are well suited to speaking opportunities where technical presentations or demonstrations are not practical or appropriate. A carefully chosen sequence of photo slides minimizes the need for speaker's notes, as each photo itself provides a visual prompt. Although photo slide presentations are appropriate to a variety of outreach and professional settings, the specific illustrative and explanatory material presented here illustrates their application in career education outreach activities, using industrial hearing conservation as an example.

Earthquake damage to schools

USGS Publications Warehouse

McCullough, Heather

1994-01-01

These unusual slides show earthquake damage to school and university buildings around the world. They graphically illustrate the potential danger to our schools, and to the welfare of our children, that results from major earthquakes. The slides range from Algeria, where a collapsed school roof is held up only by students' desks; to Anchorage, Alaska, where an elementary school structure has split in half; to California and other areas, where school buildings have sustained damage to walls, roofs, and chimneys. Interestingly, all the United States earthquakes depicted in this set of slides occurred either on a holiday or before or after school hours, except the 1935 tremor in Helena, Montana, which occurred at 11:35 am. It undoubtedly would have caused casualties had the schools not been closed days earlier by Helena city officials because of a damaging foreshock. Students in Algeria, the People's Republic of China, Armenia, and other stricken countries were not so fortunate. This set of slides represents 17 destructive earthquakes that occurred in 9 countries, and covers more than a century--from 1886 to 1988. Two of the tremors, both of which occurred in the United States, were magnitude 8+ on the Richter Scale, and four were magnitude 7-7.9. The events represented by the slides (see table below) claimed more than a quarter of a million lives.

Rotor Current Control of DFIG for Improving Fault Ride - Through Using a Novel Sliding Mode Control Approach

NASA Astrophysics Data System (ADS)

Cai, Guowei; Liu, Cheng; Yang, Deyou

2013-11-01

The doubly fed induction generators (DFIG) have been recognized as the dominant technology used in wind power generation systems with the rapid development of wind power. However, continuous operation of DFIG may cause a serious wind turbine generators tripping accident, due to destructive over-current in the rotor winding which is caused by the power system fault or inefficient fault ride-through (FRT) strategy. A new rotor current control scheme in the rotor-side converter (RSC) ispresented to enhance FRT capacities of grid-connected DFIG. Due to the strongly nonlinear nature of DFIG and insensitive to DFIG parameter's variations, a novel sliding mode controller was designed. The controller combines extended state observer (ESO) with sliding model variable structure control theory. The simulation is carried out to verify the effectiveness of the proposed control approach under various types of grid disturbances. It is shown that the proposed controller provides enhanced transient features than the classic proportional-integral control. The proposed control method can effectively reduce over-current in the RSC, and the transient pulse value of electromagnetic torque is too large under power grid fault.

Fuzzy control system for a remote focusing microscope

NASA Astrophysics Data System (ADS)

Weiss, Jonathan J.; Tran, Luc P.

1992-01-01

Space Station Crew Health Care System procedures require the use of an on-board microscope whose slide images will be transmitted for analysis by ground-based microbiologists. Focusing of microscope slides is low on the list of crew priorities, so NASA is investigating the option of telerobotic focusing controlled by the microbiologist on the ground, using continuous video feedback. However, even at Space Station distances, the transmission time lag may disrupt the focusing process, severely limiting the number of slides that can be analyzed within a given bandwidth allocation. Substantial time could be saved if on-board automation could pre-focus each slide before transmission. The authors demonstrate the feasibility of on-board automatic focusing using a fuzzy logic ruled-based system to bring the slide image into focus. The original prototype system was produced in under two months and at low cost. Slide images are captured by a video camera, then digitized by gray-scale value. A software function calculates an index of 'sharpness' based on gray-scale contrasts. The fuzzy logic rule-based system uses feedback to set the microscope's focusing control in an attempt to maximize sharpness. The systems as currently implemented performs satisfactorily in focusing a variety of slide types at magnification levels ranging from 10 to 1000x. Although feasibility has been demonstrated, the system's performance and usability could be improved substantially in four ways: by upgrading the quality and resolution of the video imaging system (including the use of full color); by empirically defining and calibrating the index of image sharpness; by letting the overall focusing strategy vary depending on user-specified parameters; and by fine-tuning the fuzzy rules, set definitions, and procedures used.

9 CFR 130.14 - User fees for FADDL veterinary diagnostics.

Code of Federal Regulations, 2012 CFR

2012-01-01

... slides or plates Slide 49.00 50.00 51.00 53.00 Reference animal tissues for immunohistochemistry Set 171... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false User fees for FADDL veterinary diagnostics. 130.14 Section 130.14 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE...

9 CFR 130.14 - User fees for FADDL veterinary diagnostics.

Code of Federal Regulations, 2013 CFR

2013-01-01

... slides or plates Slide 49.00 50.00 51.00 53.00 Reference animal tissues for immunohistochemistry Set 171... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false User fees for FADDL veterinary diagnostics. 130.14 Section 130.14 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE...

9 CFR 130.14 - User fees for FADDL veterinary diagnostics.

Code of Federal Regulations, 2014 CFR

2014-01-01

... slides or plates Slide 49.00 50.00 51.00 53.00 Reference animal tissues for immunohistochemistry Set 171... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false User fees for FADDL veterinary diagnostics. 130.14 Section 130.14 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE...

Stereoscopic Projection in Organic Chemistry: Bridging the Gap between Two and Three Dimensions.

ERIC Educational Resources Information Center

Rozzelle, Arlene A.; Rosenfeld, Stuart M.

1985-01-01

Shows how to make stereo slides of three-dimensional molecular models. The slides have been used to teach chirality, conformational isomerism, how models and two-dimensional representations embody selected aspects of structure, and fundamentals of using the specific model set required in a particular organic chemistry course. (JN)

Fostering Student Engagement with Digital Microscopic Images Using ThingLink, an Image Annotation Program

ERIC Educational Resources Information Center

Appasamy, Pierette

2018-01-01

The teaching of histology has changed dramatically with virtual microscopy. Fewer students of histology spend significant time viewing slides on a microscope and instead study images available in digital slide sets, generally accessible via the internet. However, students must still be able to correctly identify the defining characteristics of…

Planning a Financial Aid Awareness Program.

ERIC Educational Resources Information Center

Department of Education, Washington, DC.

This booklet is intended to be used with a set of slides as part of presentations to students. Each page usually includes an illustration of the accompanying slide, the basic information to be communicated, background notes and answers to common questions as appropriate. The presentation first considers why a student should go to college or career…

Definite differences between in vitro actin-myosin sliding and muscle contraction as revealed using antibodies to myosin head.

PubMed

Sugi, Haruo; Chaen, Shigeru; Kobayashi, Takakazu; Abe, Takahiro; Kimura, Kazushige; Saeki, Yasutake; Ohnuki, Yoshiki; Miyakawa, Takuya; Tanokura, Masaru; Sugiura, Seiryo

2014-01-01

Muscle contraction results from attachment-detachment cycles between myosin heads extending from myosin filaments and actin filaments. It is generally believed that a myosin head first attaches to actin, undergoes conformational changes to produce force and motion in muscle, and then detaches from actin. Despite extensive studies, the molecular mechanism of myosin head conformational changes still remains to be a matter for debate and speculation. The myosin head consists of catalytic (CAD), converter (CVD) and lever arm (LD) domains. To give information about the role of these domains in the myosin head performance, we have examined the effect of three site-directed antibodies to the myosin head on in vitro ATP-dependent actin-myosin sliding and Ca2+-activated contraction of muscle fibers. Antibody 1, attaching to junctional peptide between 50K and 20K heavy chain segments in the CAD, exhibited appreciable effects neither on in vitro actin-myosin sliding nor muscle fiber contraction. Since antibody 1 covers actin-binding sites of the CAD, one interpretation of this result is that rigor actin-myosin linkage is absent or at most a transient intermediate in physiological actin-myosin cycling. Antibody 2, attaching to reactive lysine residue in the CVD, showed a marked inhibitory effect on in vitro actin-myosin sliding without changing actin-activated myosin head (S1) ATPase activity, while it showed no appreciable effect on muscle contraction. Antibody 3, attaching to two peptides of regulatory light chains in the LD, had no significant effect on in vitro actin-myosin sliding, while it reduced force development in muscle fibers without changing MgATPase activity. The above definite differences in the effect of antibodies 2 and 3 between in vitro actin-myosin sliding and muscle contraction can be explained by difference in experimental conditions; in the former, myosin heads are randomly oriented on a glass surface, while in the latter myosin heads are regularly arranged within filament-lattice structures.

Definite Differences between In Vitro Actin-Myosin Sliding and Muscle Contraction as Revealed Using Antibodies to Myosin Head

PubMed Central

Sugi, Haruo; Chaen, Shigeru; Kobayashi, Takakazu; Abe, Takahiro; Kimura, Kazushige; Saeki, Yasutake; Ohnuki, Yoshiki; Miyakawa, Takuya; Tanokura, Masaru; Sugiura, Seiryo

2014-01-01

Muscle contraction results from attachment-detachment cycles between myosin heads extending from myosin filaments and actin filaments. It is generally believed that a myosin head first attaches to actin, undergoes conformational changes to produce force and motion in muscle, and then detaches from actin. Despite extensive studies, the molecular mechanism of myosin head conformational changes still remains to be a matter for debate and speculation. The myosin head consists of catalytic (CAD), converter (CVD) and lever arm (LD) domains. To give information about the role of these domains in the myosin head performance, we have examined the effect of three site-directed antibodies to the myosin head on in vitro ATP-dependent actin-myosin sliding and Ca2+-activated contraction of muscle fibers. Antibody 1, attaching to junctional peptide between 50K and 20K heavy chain segments in the CAD, exhibited appreciable effects neither on in vitro actin-myosin sliding nor muscle fiber contraction. Since antibody 1 covers actin-binding sites of the CAD, one interpretation of this result is that rigor actin-myosin linkage is absent or at most a transient intermediate in physiological actin-myosin cycling. Antibody 2, attaching to reactive lysine residue in the CVD, showed a marked inhibitory effect on in vitro actin-myosin sliding without changing actin-activated myosin head (S1) ATPase activity, while it showed no appreciable effect on muscle contraction. Antibody 3, attaching to two peptides of regulatory light chains in the LD, had no significant effect on in vitro actin-myosin sliding, while it reduced force development in muscle fibers without changing MgATPase activity. The above definite differences in the effect of antibodies 2 and 3 between in vitro actin-myosin sliding and muscle contraction can be explained by difference in experimental conditions; in the former, myosin heads are randomly oriented on a glass surface, while in the latter myosin heads are regularly arranged within filament-lattice structures. PMID:24918754

Closed-loop analysis and control of a non-inverting buck-boost converter

NASA Astrophysics Data System (ADS)

Chen, Zengshi; Hu, Jiangang; Gao, Wenzhong

2010-11-01

In this article, a cascade controller is designed and analysed for a non-inverting buck-boost converter. The fast inner current loop uses sliding mode control. The slow outer voltage loop uses the proportional-integral (PI) control. Stability analysis and selection of PI gains are based on the nonlinear closed-loop error dynamics incorporating both the inner and outer loop controllers. The closed-loop system is proven to have a nonminimum phase structure. The voltage transient due to step changes of input voltage or resistance is predictable. The operating range of the reference voltage is discussed. The controller is validated by a simulation circuit. The simulation results show that the reference output voltage is well-tracked under system uncertainties or disturbances, confirming the validity of the proposed controller.

The LSLE echocardiograph - Commercial hardware aboard Spacelab. [Life Sciences Laboratory Equipment

NASA Technical Reports Server (NTRS)

Schwarz, R.

1983-01-01

The Life Sciences Laboratory Equipment Echocardiograph, a commercial 77020AC Ultrasound Imaging System modified to meet NASA's spacecraft standards, is described. The assembly consists of four models: display and control, scanner, scan converter, and physioamplifiers. Four separate processors communicate over an IEE-488 bus, and the system has more than 6000 individual components on 35 printed circuit cards. Three levels of self test are provided: a short test during power up, a basic test initiated by a front panel switch, and interactive tests for specific routines. Default mode operation further enhances reliability. Modifications of the original system include the replacement of ac power supplies with dc to dc converters, a slide-out keyboard (to prevent accidental operation), Teflon insulated wire, and additional shielding for the ultrasound transducer cable.

Robust control of the DC-DC boost converter based on the uncertainty and disturbance estimator

NASA Astrophysics Data System (ADS)

Oucheriah, Said

2017-11-01

In this paper, a robust non-linear controller based on the uncertainty and disturbance estimator (UDE) scheme is successfully developed and implemented for the output voltage regulation of the DC-DC boost converter. System uncertainties, external disturbances and unknown non-linear dynamics are lumped as a signal that is accurately estimated using a low-pass filter and their effects are cancelled by the controller. This methodology forms the basis of the UDE-based controller. A simple procedure is also developed that systematically determines the parameters of the controller to meet certain specifications. Using simulation, the effectiveness of the proposed controller is compared against the sliding-mode control (SMC). Experimental tests also show that the proposed controller is robust to system uncertainties, large input and load perturbations.

Adaptive disturbance compensation finite control set optimal control for PMSM systems based on sliding mode extended state observer

NASA Astrophysics Data System (ADS)

Wu, Yun-jie; Li, Guo-fei

2018-01-01

Based on sliding mode extended state observer (SMESO) technique, an adaptive disturbance compensation finite control set optimal control (FCS-OC) strategy is proposed for permanent magnet synchronous motor (PMSM) system driven by voltage source inverter (VSI). So as to improve robustness of finite control set optimal control strategy, a SMESO is proposed to estimate the output-effect disturbance. The estimated value is fed back to finite control set optimal controller for implementing disturbance compensation. It is indicated through theoretical analysis that the designed SMESO could converge in finite time. The simulation results illustrate that the proposed adaptive disturbance compensation FCS-OC possesses better dynamical response behavior in the presence of disturbance.

The frictional response of patterned soft polymer surfaces

NASA Astrophysics Data System (ADS)

Rand, Charles J.

2008-10-01

Friction plays an intricate role in our everyday lives, it is therefore critical to understand the underlying features of friction to better help control and manipulate the response anywhere two surfaces in contact move past each other by a sliding motion. Here we present results targeting a thorough understanding of soft material friction and how it can be manipulated with patterns. We found that the naturally occurring length scale or periodicity (lambda) of frictionally induced patterns, Schallamach waves, could be described using two materials properties (critical energy release rate Gc and complex modulus (E*), i.e. lambdainfinity Gc /E*). Following this, we evaluated the effect of a single defect at a sliding interface. Sliding over a defect can be used to model the sliding from one feature to another in a patterned surface. Defects decreased the sliding frictional force by as much as 80% sliding and this decrease was attributed to changes in tangential stiffness of the sliding interface. The frictional response of surface wrinkles, where multiple edges or defects are acting in concert, was also evaluated. Wrinkles were shown to decrease friction (F) and changes in contact area (A) could not describe this decrease. A tangential stiffness correction factor (fx) and changes in the critical energy release rate were used to describe this deviation (F infinity Gc *A*fx/ℓ, where ℓ is a materials defined length scale of dissipation). This scaling can be used to describe the friction of any topographically patterned surface including the Gecko's foot, where the feature size is smaller than ℓ and thus replaces ℓ, increasing the friction compared to a flat surface. Also, mechanically-induced surface defects were used to align osmotically driven surface wrinkles by creating stress discontinuities that convert the global biaxial stress state to local uniaxial stresses. Defect spacing was used to control the alignment process at the surface of the wrinkled rigid film/soft elastomer interface. These aligned wrinkled surfaces can be used to tune the adhesion and friction of an interface. The work presented here gives insight into tuning the friction of a soft polymeric surface as well as understanding the friction of complex hierarchical structures.

SLIDE - a web-based tool for interactive visualization of large-scale -omics data.

PubMed

Ghosh, Soumita; Datta, Abhik; Tan, Kaisen; Choi, Hyungwon

2018-06-28

Data visualization is often regarded as a post hoc step for verifying statistically significant results in the analysis of high-throughput data sets. This common practice leaves a large amount of raw data behind, from which more information can be extracted. However, existing solutions do not provide capabilities to explore large-scale raw datasets using biologically sensible queries, nor do they allow user interaction based real-time customization of graphics. To address these drawbacks, we have designed an open-source, web-based tool called Systems-Level Interactive Data Exploration, or SLIDE to visualize large-scale -omics data interactively. SLIDE's interface makes it easier for scientists to explore quantitative expression data in multiple resolutions in a single screen. SLIDE is publicly available under BSD license both as an online version as well as a stand-alone version at https://github.com/soumitag/SLIDE. Supplementary Information are available at Bioinformatics online.

Tribology of the lubricant quantized sliding state.

PubMed

Castelli, Ivano Eligio; Capozza, Rosario; Vanossi, Andrea; Santoro, Giuseppe E; Manini, Nicola; Tosatti, Erio

2009-11-07

In the framework of Langevin dynamics, we demonstrate clear evidence of the peculiar quantized sliding state, previously found in a simple one-dimensional boundary lubricated model [A. Vanossi et al., Phys. Rev. Lett. 97, 056101 (2006)], for a substantially less idealized two-dimensional description of a confined multilayer solid lubricant under shear. This dynamical state, marked by a nontrivial "quantized" ratio of the averaged lubricant center-of-mass velocity to the externally imposed sliding speed, is recovered, and shown to be robust against the effects of thermal fluctuations, quenched disorder in the confining substrates, and over a wide range of loading forces. The lubricant softness, setting the width of the propagating solitonic structures, is found to play a major role in promoting in-registry commensurate regions beneficial to this quantized sliding. By evaluating the force instantaneously exerted on the top plate, we find that this quantized sliding represents a dynamical "pinned" state, characterized by significantly low values of the kinetic friction. While the quantized sliding occurs due to solitons being driven gently, the transition to ordinary unpinned sliding regimes can involve lubricant melting due to large shear-induced Joule heating, for example at large speed.

Ergonomic evaluation of slide boards used by home care aides to assist client transfers.

PubMed

Sun, Chuan; Buchholz, Bryan; Quinn, Margaret; Punnett, Laura; Galligan, Catherine; Gore, Rebecca

2018-07-01

Home care aides risk musculoskeletal injury because they lift and move clients; the body weight of most adults exceeds the NIOSH recommended limit for lifting. Methods to reduce manual patient lifting in institutional settings are often technically or economically infeasible in home care. Our goal was to identify suitable, safe, low-technology transfer devices for home care use. Sixteen experienced home care aides performed client transfers from wheelchair to bed (upward) and bed to wheelchair (downward) in a simulated home care environment (laboratory), using four different slide boards and by hand without a device. Aides' hand forces were measured during client transfers; aides also evaluated usability of each board. Hand forces exerted while using slide boards were mostly lower than in manual transfer, and forces were lower in downward versus upward transfers. Aides judged a board with a sliding mechanism easier to use than boards without a sliding mechanism. Practitioner Summary: This paper provides quantitative biomechanical measurements showing that slide boards reduced the hand forces needed by home care aides to transfer clients from bed to wheel chair and vice versa, compared to manual lifting. Using a semi-quantitative usability survey, aides identified boards with a sliding mechanism easiest to use.

Fuel-cell based power generating system having power conditioning apparatus

DOEpatents

Mazumder, Sudip K.; Pradhan, Sanjaya K.

2010-10-05

A power conditioner includes power converters for supplying power to a load, a set of selection switches corresponding to the power converters for selectively connecting the fuel-cell stack to the power converters, and another set of selection switches corresponding to the power converters for selectively connecting the battery to the power converters. The power conveners output combined power that substantially optimally meets a present demand of the load.

Application of Digital Radiography to Weld Inspection for the Space Shuttle External Fuel Tank

NASA Technical Reports Server (NTRS)

Ussery, Warren

2009-01-01

This slide presentation reviews NASA's use of digital radiography to inspect the welds of the external tanks used to hold the cryogenic fuels for the Space Shuttle Main Engines. NASA has had a goal of replacing a significant portion of film used to inspect the welds, with digital radiography. The presentation reviews the objectives for converting to a digital system from film, the characteristics of the digital system, the Probability of detection study, the qualification and implementation of the system.

Localization of Diagnostically Relevant Regions of Interest in Whole Slide Images: a Comparative Study.

PubMed

Mercan, Ezgi; Aksoy, Selim; Shapiro, Linda G; Weaver, Donald L; Brunyé, Tad T; Elmore, Joann G

2016-08-01

Whole slide digital imaging technology enables researchers to study pathologists' interpretive behavior as they view digital slides and gain new understanding of the diagnostic medical decision-making process. In this study, we propose a simple yet important analysis to extract diagnostically relevant regions of interest (ROIs) from tracking records using only pathologists' actions as they viewed biopsy specimens in the whole slide digital imaging format (zooming, panning, and fixating). We use these extracted regions in a visual bag-of-words model based on color and texture features to predict diagnostically relevant ROIs on whole slide images. Using a logistic regression classifier in a cross-validation setting on 240 digital breast biopsy slides and viewport tracking logs of three expert pathologists, we produce probability maps that show 74 % overlap with the actual regions at which pathologists looked. We compare different bag-of-words models by changing dictionary size, visual word definition (patches vs. superpixels), and training data (automatically extracted ROIs vs. manually marked ROIs). This study is a first step in understanding the scanning behaviors of pathologists and the underlying reasons for diagnostic errors.

Rapid testing for malaria in settings where microscopy is available and peripheral clinics where only presumptive treatment is available: a randomised controlled trial in Ghana.

PubMed

Ansah, Evelyn K; Narh-Bana, Solomon; Epokor, Michael; Akanpigbiam, Samson; Quartey, Alberta Amu; Gyapong, John; Whitty, Christopher J M

2010-03-05

To test in West Africa the impact of rapid diagnostic tests on the prescription of antimalarials and antibiotics both where microscopy is used for the diagnosis of malaria and in clinical (peripheral) settings that rely on clinical diagnosis. Randomised, controlled, open label clinical trial. Four clinics in the rural Dangme West district of southern Ghana, one in which microscopy is used for diagnosis of malaria ("microscopy setting") and three where microscopy is not available and diagnosis of malaria is made on the basis of clinical symptoms ("clinical setting"). Patients with suspected malaria. Interventions Patients were randomly assigned to either a rapid diagnostic test or the current diagnostic method at the clinic (microscopy or clinical diagnosis). A blood sample for a research microscopy slide was taken for all patients. The primary outcome was the prescription of antimalarials to patients of any age whose double read research slide was negative for malaria. The major secondary outcomes were the correct prescription of antimalarials, the impact of test results on antibiotic prescription, and the correct prescription of antimalarials in children under 5 years. Of the 9236 patients screened, 3452 were randomised in the clinical setting and 3811 in the microscopy setting. Follow-up to 28 days was 97.6% (7088/7263). In the microscopy setting, 722 (51.6%) of the 1400 patients with negative research slides in the rapid diagnostic test arm were treated for malaria compared with 764 (55.0%) of the 1389 patients in the microscopy arm (adjusted odds ratio 0.87, 95% CI 0.71 to 1.1; P=0.16). In the clinical setting, 578 (53.9%) of the 1072 patients in the rapid diagnostic test arm with negative research slides were treated for malaria compared with 982 (90.1%) of the 1090 patients with negative slides in the clinical diagnosis arm (odds ratio 0.12, 95% CI 0.04 to 0.38; P=0.001). The use of rapid diagnostic tests led to better targeting of antimalarials and antibiotics in the clinical but not the microscopy setting, in both children and adults. There were no deaths in children under 5 years at 28 days follow-up in either arm. Where microscopy already exists, introducing rapid diagnostic tests had limited impact on prescriber behaviour. In settings where microscopy was not available, however, using rapid diagnostic tests led to a significant reduction in the overprescription of antimalarials, without any evidence of clinical harm, and to better targeting of antibiotics. Trial registration ClinicalTrials.gov NCT00493922.

Sliding mode control: an approach to regulate nonlinear chemical processes

PubMed

Camacho; Smith

2000-01-01

A new approach for the design of sliding mode controllers based on a first-order-plus-deadtime model of the process, is developed. This approach results in a fixed structure controller with a set of tuning equations as a function of the characteristic parameters of the model. The controller performance is judged by simulations on two nonlinear chemical processes.

How Prior Knowledge and Colour Contrast Interfere Visual Search Processes in Novice Learners: An Eye Tracking Study

ERIC Educational Resources Information Center

Sonmez, Duygu; Altun, Arif; Mazman, Sacide Guzin

2012-01-01

This study investigates how prior content knowledge and prior exposure to microscope slides on the phases of mitosis effect students' visual search strategies and their ability to differentiate cells that are going through any phases of mitosis. Two different sets of microscope slide views were used for this purpose; with high and low colour…

Whole-slide imaging: routine pathologic diagnosis.

PubMed

Cornish, Toby C; Swapp, Ryan E; Kaplan, Keith J

2012-05-01

Digital pathology systems offer pathologists an alternate, emerging mechanism to manage and interpret information. They offer increasingly fast and scalable hardware platforms for slide scanning and software that facilitates remote viewing, slide conferencing, archiving, and image analysis. Deployed initially and validated largely within the research and biopharmaceutical industries, WSI is increasingly being implemented for direct patient care. Improvements in image quality, scan times, and imageviewing browsers will hopefully allow pathologists to more seamlessly convert to digital pathology, much like our radiology colleagues have done before us. However, WSI creates both opportunities and challenges. Although niche applications of WSI technology for clinical, educational, and research purposes are clearly successful, it is evident that several areas still require attention and careful consideration before more widespread clinical adoption of WSI takes place. These include regulatory issues, development of standards of practice and validation guidelines, workflow modifications, as well as defining situations where WSI technology will really improve practice in a cost-effective way. Current progress on these and other issues, along with improving technology, will no doubt pave the way for increased adoption over the next decade, allowing the pathology community as a whole to harness the true potential of WSI for patient care. The digital decade will likely redefine how pathology is practiced and the role of the pathologist.

A new adjustable gains for second order sliding mode control of saturated DFIG-based wind turbine

NASA Astrophysics Data System (ADS)

Bounadja, E.; Djahbar, A.; Taleb, R.; Boudjema, Z.

2017-02-01

The control of Doubly-Fed induction generator (DFIG), used in wind energy conversion, has been given a great deal of interest. Frequently, this control has been dealt with ignoring the magnetic saturation effect in the DFIG model. The aim of the present work is twofold: firstly, the magnetic saturation effect is accounted in the control design model; secondly, a new second order sliding mode control scheme using adjustable-gains (AG-SOSMC) is proposed to control the DFIG via its rotor side converter. This scheme allows the independent control of the generated active and reactive power. Conventionally, the second order sliding mode control (SOSMC) applied to the DFIG, utilize the super-twisting algorithm with fixed gains. In the proposed AG-SOSMC, a simple means by which the controller can adjust its behavior is used. For that, a linear function is used to represent the variation in gain as a function of the absolute value of the discrepancy between the reference rotor current and its measured value. The transient DFIG speed response using the aforementioned characteristic is compared with the one determined by using the conventional SOSMC controller with fixed gains. Simulation results show, accurate dynamic performances, quicker transient response and more accurate control are achieved for different operating conditions.

Direct-current triboelectricity generation by a sliding Schottky nanocontact on MoS2 multilayers

NASA Astrophysics Data System (ADS)

Liu, Jun; Goswami, Ankur; Jiang, Keren; Khan, Faheem; Kim, Seokbeom; McGee, Ryan; Li, Zhi; Hu, Zhiyu; Lee, Jungchul; Thundat, Thomas

2018-02-01

The direct conversion of mechanical energy into electricity by nanomaterial-based devices offers potential for green energy harvesting1-3. A conventional triboelectric nanogenerator converts frictional energy into electricity by producing alternating current (a.c.) triboelectricity. However, this approach is limited by low current density and the need for rectification2. Here, we show that continuous direct-current (d.c.) with a maximum density of 106 A m-2 can be directly generated by a sliding Schottky nanocontact without the application of an external voltage. We demonstrate this by sliding a conductive-atomic force microscope tip on a thin film of molybdenum disulfide (MoS2). Finite element simulation reveals that the anomalously high current density can be attributed to the non-equilibrium carrier transport phenomenon enhanced by the strong local electrical field (105-106 V m-2) at the conductive nanoscale tip4. We hypothesize that the charge transport may be induced by electronic excitation under friction, and the nanoscale current-voltage spectra analysis indicates that the rectifying Schottky barrier at the tip-sample interface plays a critical role in efficient d.c. energy harvesting. This concept is scalable when combined with microfabricated or contact surface modified electrodes, which makes it promising for efficient d.c. triboelectricity generation.

Comparison study of the rates of manual peripheral blood smear review from 3 automated hematology analyzers, Unicel DxH 800, ADVIA 2120i, and XE 2100, using international consensus group guidelines.

PubMed

Kim, Sue Jung; Kim, Yoonjung; Shin, Saeam; Song, Jaewoo; Choi, Jong Rak

2012-11-01

In the clinical laboratory, it is important both to reduce the number of peripheral blood slide reviews to save time and money and to avoid reporting false results. To determine differences in the slide review rates of 3 widely used automated hematologic analyzers, the Unicel DxH 800 (Beckman Coulter Inc, Fullerton, California), ADVIA 2120i (Siemens Diagnostics, Tarrytown, New York), and XE 2100 (Sysmex, Kobe, Japan), using International Consensus Group for Hematology Review guidelines. A total of 1485 samples were tested, and 300 were manually reviewed. Slide review rates, sensitivity, specificity, and false-positive and false-negative rates were estimated using consensus group rules and compared using χ(2) tests, Fisher exact tests, or generalized estimating equations. Unicel DxH 800, ADVIA 2120i, and XE 2100 showed 22.8%, 20.2%, and 28.6% slide review rates; 14.3%, 14.3%, and 9.7% false-negative rates; and 13.7, 11.3%, and 17.3% false-positive rates, respectively. All analyzers showed significantly higher false-negative rates than that of the consensus group (2.9%). False-negative rates were higher than the recommended levels. Among 3 automated hematologic analyzers, XE 2100 showed the highest rate of slide review. Because the present study clearly shows that the slide review rates have distinct characteristics among the studied analyzers, each individual laboratory should consider selecting the most appropriate analyzer according to clinical characteristics. Analyzers with high sensitivity may be advantageous in outpatient settings for screening patients, whereas analyzers with high specificity may be beneficial in inpatient settings for efficient patient care.

Bifurcation Analysis of a DC-DC Bidirectional Power Converter Operating with Constant Power Loads

NASA Astrophysics Data System (ADS)

Cristiano, Rony; Pagano, Daniel J.; Benadero, Luis; Ponce, Enrique

Direct current (DC) microgrids (MGs) are an emergent option to satisfy new demands for power quality and integration of renewable resources in electrical distribution systems. This work addresses the large-signal stability analysis of a DC-DC bidirectional converter (DBC) connected to a storage device in an islanding MG. This converter is responsible for controlling the balance of power (load demand and generation) under constant power loads (CPLs). In order to control the DC bus voltage through a DBC, we propose a robust sliding mode control (SMC) based on a washout filter. Dynamical systems techniques are exploited to assess the quality of this switching control strategy. In this sense, a bifurcation analysis is performed to study the nonlinear stability of a reduced model of this system. The appearance of different bifurcations when load parameters and control gains are changed is studied in detail. In the specific case of Teixeira Singularity (TS) bifurcation, some experimental results are provided, confirming the mathematical predictions. Both a deeper insight in the dynamic behavior of the controlled system and valuable design criteria are obtained.

Fast acting multiple element valve

DOEpatents

Yang, Jefferson Y. S.; Wada, James M.

1991-01-01

A plurality of slide valve elements having plural axial-spaced annular parts and an internal slide are inserted into a bulkhead in a fluid conduit from a downstream side of the bulkhead, locked in place by a bayonet coupling and set screw, and project through the bulkhead into the upstream conduit. Pneumatic lines connecting the slide valve element actuator to pilot valves are brought out the throat of the valve element to the downstream side. Pilot valves are radially spaced around the exterior of the valve to permit the pneumatic lines to be made identical, thereby to minimize adverse timing tolerances in operation due to pressure variations. Ring manifolds surround the valve adjacent respective pilot valve arrangements to further reduce adverse timing tolerances due to pressure variations, the manifolds being directly connected to the respective pilot valves. Position sensors are provided the valve element slides to signal the precise time at which a slide reaches or passes through a particular point in its stroke to initiate a calibrated timing function.

Assessing and Improving Student Organizations: Resources for Facilitators CD-ROM. The Assessing and Improving Student Organization (AISO) Program

ERIC Educational Resources Information Center

Nolfi, Tricia; Ruben, Brent D.

2010-01-01

This companion to the "Guide for Students" and "Student Workbook" includes the complete set of PowerPoint slides, a PDF of the Facilitator's Guide in PPT (PowerPoint) slide show format, and PDFs of all scoring sheets, handouts and project planning guides needed for the AISO (Assessing and Improving Student Organization) process. The Assessing and…

A sliding mode control proposal for open-loop unstable processes.

PubMed

Rojas, Rubén; Camacho, Oscar; González, Luis

2004-04-01

This papers presents a sliding mode controller based on a first-order-plus-dead-time model of the process for controlling open-loop unstable systems. The proposed controller has a simple and fixed structure with a set of tuning equations as a function of the desired performance. Both linear and nonlinear models were used to study the controller performance by computer simulations.

Testing CuO nanowires as a novel X-ray to electron converter for gas-filled radiation detectors

NASA Astrophysics Data System (ADS)

Zarei, H.; Saramad, S.; Razaghi, S.

2017-10-01

Nanowires, due to their special physical properties and also high surface to volume ratio, can have considerable applications in designing and development of novel nanodevices. For the radiation shielding, higher absorption coefficient of nanostructures in comparison to bulk ones is an advantage. In gas detectors, designing a proper converter that absorbs higher energy of gamma and X-rays and convert it to more free electrons is one of the major problems. Since the nanowires have higher surface to volume ratio in comparison to the bulk one, so it is expected that by optimizing the thickness, the generated electrons can have higher chance to escape from the surface. In this work, the random CuO nanowires with diameter of 40 nm are deposited on thin glass slide. This nanostructure with different thicknesses are tested by plastic and CsI scintillators by X-ray tube with HVs in the range of 16 to 25 kV. The results show that for the same thickness, the CuO nanowires can release electrons six times more than the bulk ones and for the same energy the optimum QE of nanoconverter can be three times greater than the bulk converter. This novel nanoconverter with higher detection efficiency can have applications in high energy physics, medical imaging and also astronomy.

Slide-induced waves, seiching and ground fracturing caused by the earthquake of March 27, 1964 at Kenai Lake, Alaska: Chapter A in The Alaska earthquake, March 27, 1964: regional effects

USGS Publications Warehouse

McCulloch, David S.

1966-01-01

The March 27, 1964, earthquake dislodged slides from nine deltas in Kenai Lake, south-central Alaska. Sliding removed protruding parts of deltas-often the youngest parts-and steepened delta fronts, increasing the chances of further sliding. Fathograms show that debris from large slides spread widely over the lake floor, some reaching the toe of the opposite shore; at one place debris traveled 5,000 feet over the horizontal lake floor. Slides generated two kinds of local waves: a backfill and far-shore wave. Backfill waves were formed by water that rushed toward the delta to fill the void left by the sinking slide mass, overtopped the slide scrap, and came ashore over the delta. Some backfill waves had runup heights of 30 feet and ran inland more than 300 feet, uprooting and breaking off large trees. Far-shore waves hit the shore opposite the slides. They were formed by slide debris that crossed the lake floor and forced water ahead of it, which then ran up the opposite slope, burst above the lake surface, and struck the shore. One far-shore wave had a runup height of 72 feet. Kenai Lake was tilted and seiched; a power spectrum analysis of a limnogram shows a wave having the period of the calculated uninodal seiche (36 minutes) and several shorter period waves. In constricted and shallow reaches, waves caused by seiching had 20- and 30-foot runup heights. Deep lateral spreading of sediments toward delta margins displaced deeply driven railroad-bridge piles, and set up stress fields in the surface sediments which resulted in the formation of many shear and some tension fractures on the surface of two deltas.

Effect of surface mobility on the particle sliding along a bubble or a solid sphere.

PubMed

Wang, Weixing; Zhou, Zhiang; Nandakumar, K; Xu, Zhenghe; Masliyah, Jacob H

2003-03-01

The sliding velocity of glass beads on a spherical surface, made either of an air bubble or of a glass sphere held stationary, is measured to investigate the effect of surface mobility on the particle sliding velocity. The sliding process is recorded with a digital camera and analyzed frame by frame. The sliding glass bead was found to accelerate with increasing angular position on the collector's surface. It reaches a maximum velocity at an angular position of about 100 degrees and then, under certain conditions, the glass bead leaves the surface of the collector. The sliding velocity of the glass bead depends strongly on the surface mobility of a bubble, decreasing with decreasing surface mobility. By a mobile surface we mean one which cannot set up resistive forces to an applied stress on the surface. The sliding velocity on a rigid surface, such as a glass sphere, is much lower than that on a mobile bubble surface. The sliding velocity can be described through a modified Stokes equation. A numerical factor in the modified Stokes equation is determined by fitting the experimental data and is found to increase with decreasing surface mobility. Hydrophobic glass beads sliding on a hydrophobic glass sphere were found to stick at the point of impact without sliding if the initial angular position of the impact is less than some specific angle, which is defined as the critical sticking angle. The sticking of the glass beads can be attributed to the capillary contracting force created by the formation of a cavity due to spontaneous receding of the nonwetting liquid from the contact zone. The relationship between the critical sticking angle and the particle size is established based on the Yushchenko [J. Colloid Interface Sci. 96 (1983) 307] analysis.

Smith predictor based-sliding mode controller for integrating processes with elevated deadtime.

PubMed

Camacho, Oscar; De la Cruz, Francisco

2004-04-01

An approach to control integrating processes with elevated deadtime using a Smith predictor sliding mode controller is presented. A PID sliding surface and an integrating first-order plus deadtime model have been used to synthesize the controller. Since the performance of existing controllers with a Smith predictor decrease in the presence of modeling errors, this paper presents a simple approach to combining the Smith predictor with the sliding mode concept, which is a proven, simple, and robust procedure. The proposed scheme has a set of tuning equations as a function of the characteristic parameters of the model. For implementation of our proposed approach, computer based industrial controllers that execute PID algorithms can be used. The performance and robustness of the proposed controller are compared with the Matausek-Micić scheme for linear systems using simulations.

Welded slump-graded sand couplets: evidence for slide generated turbidity currents

NASA Astrophysics Data System (ADS)

Stanley, Daniel Jean

1982-09-01

Some massive channelized strata preserved in the rock record are characterized by a lower slump member which evolves upward to a turbidite. This merging is indicative of probable generation of sediment gravity flows from submarine sliding. Conditions essential for deposition of such sequences are short transport distance between point of failure and depositional site, and an environment likely to retain both facies. Fan valleys are a likely setting for welded couplets: flowing sand, initiated by the sliding event, comes to rest at nearly the same time and position as the slump mass deposited near the base of the valley wall and in the axis proper.

NCHHSTP Atlas

MedlinePlus

... disease and a combined set for all diseases. Social Determinants of Health Slide Sets County-level data on poverty, income, ... Hepatitis Slideset HIV Slideset STD Slideset Tuberculosis Slideset Social Determinants of Health Slideset Buttons AtlasPlus Application File Formats Help: How ...

DICOM to print, 35-mm slides, web, and video projector: tutorial using Adobe Photoshop.

PubMed

Gurney, Jud W

2002-10-01

Preparing images for publication has dealt with film and the photographic process. With picture archiving and communications systems, many departments will no longer produce film. This will change how images are produced for publication. DICOM, the file format for radiographic images, has to be converted and then prepared for traditional publication, 35-mm slides, the newest techniques of video projection, and the World Wide Web. Tagged image file format is the common format for traditional print publication, whereas joint photographic expert group is the current file format for the World Wide Web. Each medium has specific requirements that can be met with a common image-editing program such as Adobe Photoshop (Adobe Systems, San Jose, CA). High-resolution images are required for print, a process that requires interpolation. However, the Internet requires images with a small file size for rapid transmission. The resolution of each output differs and the image resolution must be optimized to match the output of the publishing medium.

Turning Microscopy in the Medical Curriculum Digital: Experiences from The Faculty of Health and Medical Sciences at University of Copenhagen

PubMed Central

Vainer, Ben; Mortensen, Niels Werner; Poulsen, Steen Seier; Sørensen, Allan Have; Olsen, Jørgen; Saxild, Hans Henrik; Johansen, Flemming Fryd

2017-01-01

Familiarity with the structure and composition of normal tissue and an understanding of the changes that occur during disease is pivotal to the study of the human body. For decades, microscope slides have been central to teaching pathology in medical courses and related subjects at the University of Copenhagen. Students had to learn how to use a microscope and envisage three-dimensional processes that occur in the body from two-dimensional glass slides. Here, we describe how a PathXL virtual microscopy system for teaching pathology and histology at the Faculty has recently been implemented, from an administrative, an economic, and a teaching perspective. This fully automatic digital microscopy system has been received positively by both teachers and students, and a decision was made to convert all courses involving microscopy to the virtual microscopy format. As a result, conventional analog microscopy will be phased out from the fall of 2016. PMID:28382225

Automated analysis and classification of melanocytic tumor on skin whole slide images.

PubMed

Xu, Hongming; Lu, Cheng; Berendt, Richard; Jha, Naresh; Mandal, Mrinal

2018-06-01

This paper presents a computer-aided technique for automated analysis and classification of melanocytic tumor on skin whole slide biopsy images. The proposed technique consists of four main modules. First, skin epidermis and dermis regions are segmented by a multi-resolution framework. Next, epidermis analysis is performed, where a set of epidermis features reflecting nuclear morphologies and spatial distributions is computed. In parallel with epidermis analysis, dermis analysis is also performed, where dermal cell nuclei are segmented and a set of textural and cytological features are computed. Finally, the skin melanocytic image is classified into different categories such as melanoma, nevus or normal tissue by using a multi-class support vector machine (mSVM) with extracted epidermis and dermis features. Experimental results on 66 skin whole slide images indicate that the proposed technique achieves more than 95% classification accuracy, which suggests that the technique has the potential to be used for assisting pathologists on skin biopsy image analysis and classification. Copyright © 2018 Elsevier Ltd. All rights reserved.

Como preparar un programa de informacion sobre la asistencia economica (Planning a Financial Aid Awareness Program).

ERIC Educational Resources Information Center

Department of Education, Washington, DC.

This booklet, written in Spanish, is intended to be used with a set of slides as part of a presentation to students on "How To Apply for Federal Student Aid" ("Como Solicitar la Asistencia Economica Federal para Estudiantes"). The first part of the book is a script based on the slides. After the script is a guide to hosting a financial aid…

Robust and real-time rotor control with magnetic bearings

NASA Technical Reports Server (NTRS)

Sinha, A.; Wang, K. W.; Mease, K. L.

1991-01-01

This paper deals with the sliding mode control of a rigid rotor via radial magnetic bearings. The digital control algorithm and the results from numerical simulations are presented for an experimental rig. The experimental system which has been set up to digitally implement and validate the sliding mode control algorithm is described. Two methods for the development of control softwares are presented. Experimental results for individual rotor axis are discussed.

Tissue floaters and contaminants in the histology laboratory.

PubMed

Platt, Eric; Sommer, Paul; McDonald, Linda; Bennett, Ana; Hunt, Jennifer

2009-06-01

Anatomic pathology diagnosis is often based on morphologic features. In recent years, an appropriate increased attention to patient safety has led to an emphasis on improving maintenance of patient identity. Decreasing or eliminating cross-contamination from one specimen to another is an example of a patient identity issue for which process improvement can be initiated. To quantify the presence of cross-contamination from histology water baths and the slide stainers. We assessed for the presence of contaminants in water baths at cutting stations and in linear stainer stain baths. We assessed the potential for tissue discohesion and carryover in tissue samples and we assessed the potential for carryover onto blank slides sent through the stainer. In the 13 water baths examined (totalling 195 L of water), only one fragment of tissue was identified. The stain baths, however, contained abundant tissue contaminants, ranging in size from 2 to 3 cells to hundreds of cells. The first sets of xylenes and alcohols were the most heavily contaminated. Cross-contamination to blank slides occurred at a rate of 8%, with the highest frequency in the late afternoon. Cross-contamination can present a significant challenge in the histology laboratory. Although the histotechnologists' water baths are not heavily contaminated, the stainer baths do contain contaminating tissue fragments. Cross-contamination does occur onto blank slides in the experimental setting.

Safety in the Chemical Laboratory: An Undergraduate Chemical Laboratory Safety Course.

ERIC Educational Resources Information Center

Nicholls, L. Jewel

1982-01-01

Describes a two-quarter hour college chemistry course focusing on laboratory safety. Includes lists of topics/assignments, problem sets (toxicology, storage, and energy) and videotapes, films, and slide sets used in the course. (JN)

Efficient Residue to Binary Conversion Based on a Modified Flexible Moduli Set

NASA Astrophysics Data System (ADS)

Molahosseini, Amir Sabbagh

2011-09-01

The Residue Number System (RNS) is a non-weighted number system which can perform addition (subtraction) and multiplication on residues without carry-propagation; resulting in high-speed hardware implementations of computation systems. The problem of converting residue numbers to equivalent binary weighted form has been attracted a lot of research for many years. Recently, some researchers proposed using flexible moduli sets instead of previous traditional moduli sets to enhance the performance of residue to binary converters. This paper introduces the modified flexible moduli set {22p+k. 22p+1, 2p+1, 2p-1} which is achieved from the flexible set {2p+k, 22p+1, 2p+1, 2p-1} by enhancing modulo 2p+k. Next, new Chinese remainder theorem-1 is used to design simple and efficient residue to binary converter for this modified set with better performance than the converter of the moduli set {2p+k, 22p+1, 2p+1, 2p-1}.

Codimension-1 Sliding Bifurcations of a Filippov Pest Growth Model with Threshold Policy

NASA Astrophysics Data System (ADS)

Tang, Sanyi; Tang, Guangyao; Qin, Wenjie

A Filippov system is proposed to describe the stage structured nonsmooth pest growth with threshold policy control (TPC). The TPC measure is represented by the total density of both juveniles and adults being chosen as an index for decisions on when to implement chemical control strategies. The proposed Filippov system can have three pieces of sliding segments and three pseudo-equilibria, which result in rich sliding mode bifurcations and local sliding bifurcations including boundary node (boundary focus, or boundary saddle) and tangency bifurcations. As the threshold density varies the model exhibits the interesting global sliding bifurcations sequentially: touching → buckling → crossing → sliding homoclinic orbit to a pseudo-saddle → crossing → touching bifurcations. In particular, bifurcation of a homoclinic orbit to a pseudo-saddle with a figure of eight shape, to a pseudo-saddle-node or to a standard saddle-node have been observed for some parameter sets. This implies that control outcomes are sensitive to the threshold level, and hence it is crucial to choose the threshold level to initiate control strategy. One more sliding segment (or pseudo-equilibrium) is induced by the total density of a population guided switching policy, compared to only the juvenile density guided policy, implying that this control policy is more effective in terms of preventing multiple pest outbreaks or causing the density of pests to stabilize at a desired level such as an economic threshold.

Image Montaging for Creating a Virtual Pathology Slide: An Innovative and Economical Tool to Obtain a Whole Slide Image

PubMed Central

Pandurangappa, Rohit; Annavajjula, Saileela; Rajashekaraiah, Premalatha Bidadi

2016-01-01

Background. Microscopes are omnipresent throughout the field of biological research. With microscopes one can see in detail what is going on at the cellular level in tissues. Though it is a ubiquitous tool, the limitation is that with high magnification there is a small field of view. It is often advantageous to see an entire sample at high magnification. Over the years technological advancements in optics have helped to provide solutions to this limitation of microscopes by creating the so-called dedicated “slide scanners” which can provide a “whole slide digital image.” These scanners can provide seamless, large-field-of-view, high resolution image of entire tissue section. The only disadvantage of such complete slide imaging system is its outrageous cost, thereby hindering their practical use by most laboratories, especially in developing and low resource countries. Methods. In a quest for their substitute, we tried commonly used image editing software Adobe Photoshop along with a basic image capturing device attached to a trinocular microscope to create a digital pathology slide. Results. The seamless image created using Adobe Photoshop maintained its diagnostic quality. Conclusion. With time and effort photomicrographs obtained from a basic camera-microscope set up can be combined and merged in Adobe Photoshop to create a whole slide digital image of practically usable quality at a negligible cost. PMID:27747147

Image Montaging for Creating a Virtual Pathology Slide: An Innovative and Economical Tool to Obtain a Whole Slide Image.

PubMed

Banavar, Spoorthi Ravi; Chippagiri, Prashanthi; Pandurangappa, Rohit; Annavajjula, Saileela; Rajashekaraiah, Premalatha Bidadi

2016-01-01

Background . Microscopes are omnipresent throughout the field of biological research. With microscopes one can see in detail what is going on at the cellular level in tissues. Though it is a ubiquitous tool, the limitation is that with high magnification there is a small field of view. It is often advantageous to see an entire sample at high magnification. Over the years technological advancements in optics have helped to provide solutions to this limitation of microscopes by creating the so-called dedicated "slide scanners" which can provide a "whole slide digital image." These scanners can provide seamless, large-field-of-view, high resolution image of entire tissue section. The only disadvantage of such complete slide imaging system is its outrageous cost, thereby hindering their practical use by most laboratories, especially in developing and low resource countries. Methods . In a quest for their substitute, we tried commonly used image editing software Adobe Photoshop along with a basic image capturing device attached to a trinocular microscope to create a digital pathology slide. Results . The seamless image created using Adobe Photoshop maintained its diagnostic quality. Conclusion . With time and effort photomicrographs obtained from a basic camera-microscope set up can be combined and merged in Adobe Photoshop to create a whole slide digital image of practically usable quality at a negligible cost.

A developmental model of recreation choice behavior

Treesearch

Daniel R. Williams

1985-01-01

Recreation choices are viewed as including, at least implicitly, a selection of an activity, a setting, and a set of companions. With development these three elements become increasingly differentiated from one another. The model is tested by examining the perceived similarities among a set of 15 recreation choices depicted in color slides.

Expression Analysis of p16, c-Myc, and mSin3A in Non-small Cell Lung Cancer by Computer Aided Scoring and Analysis (CASA).

PubMed

Salmaninejad, Arash; Estiar, Mehrdad Asghari; Gill, Rajbir K; Shih, Joanna H; Hewitt, Stephen; Jeon, Hyo-Sung; Fukuoka, Junya; Shilo, Konstantin; Shakoori, Abbas; Jen, Jin

2015-01-01

Immunohistochemical analysis (IHC) of tissue microarray (TMA) slides enables large sets of tissue samples to be analyzed simultaneously on a single slide. However, manual evaluation of small cores on a TMA slide is time consuming and error prone. We describe a computer aided scoring and analysis (CASA) method to allow facile and reliable scoring of IHC staining using TMA containing 300 non-small cell lung cancer (NSCLC) cases. In the two previous published papers utilizing our TMA slides of lung cancer we examined 18 proteins involved in the chromatin machinery. We developed our study using more proteins of the chromatin complex and several transcription factors that facilitate the chromatin machinery. Then, a total of 78 antibodies were evaluated by CASA to derive a normalized intensity value that correlated with the overall staining status of the targeting protein. The intensity values for TMA cores were then examined for association to clinical variables and predictive significance individually and with other factors. RESULTs: Using our TMA, the intensity of several protein pairs were significantly correlated with an increased risk of death in NSCLC. These included c-Myc with p16, mSin3A with p16 and c-Myc with mSinA. Predictive values of these pairs remained significant when evaluated based on standard IHC scores. Our results demonstrate the usefulness of CASA as a valuable tool for systematic assessment of TMA slides to identify potential predictive biomarkers using a large set of primary human tissues.

Observer-based robust finite time H∞ sliding mode control for Markovian switching systems with mode-dependent time-varying delay and incomplete transition rate.

PubMed

Gao, Lijun; Jiang, Xiaoxiao; Wang, Dandan

2016-03-01

This paper investigates the problem of robust finite time H∞ sliding mode control for a class of Markovian switching systems. The system is subjected to the mode-dependent time-varying delay, partly unknown transition rate and unmeasurable state. The main difficulty is that, a sliding mode surface cannot be designed based on the unknown transition rate and unmeasurable state directly. To overcome this obstacle, the set of modes is firstly divided into two subsets standing for known transition rate subset and unknown one, based on which a state observer is established. A component robust finite-time sliding mode controller is also designed to cope with the effect of partially unknown transition rate. It is illustrated that the reachability, finite-time stability, finite-time boundedness, finite-time H∞ state feedback stabilization of sliding mode dynamics can be ensured despite the unknown transition rate. Finally, the simulation results verify the effectiveness of robust finite time control problem. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Development of an Organic Rankine Cycle system for exhaust energy recovery in internal combustion engines

NASA Astrophysics Data System (ADS)

Cipollone, Roberto; Bianchi, Giuseppe; Gualtieri, Angelo; Di Battista, Davide; Mauriello, Marco; Fatigati, Fabio

2015-11-01

Road transportation is currently one of the most influencing sectors for global energy consumptions and CO2 emissions. Nevertheless, more than one third of the fuel energy supplied to internal combustion engines is still rejected to the environment as thermal waste at the exhaust. Therefore, a greater fuel economy might be achieved recovering the energy from exhaust gases and converting it into useful power on board. In the current research activity, an ORC-based energy recovery system was developed and coupled with a diesel engine. The innovative feature of the recovery power unit relies upon the usage of sliding vane rotary machines as pump and expander. After a preliminary exhaust gas mapping, which allowed to assess the magnitude of the thermal power to be recovered, a thermodynamic analysis was carried out to design the ORC system and the sliding vane machines using R236fa as working fluid. An experimental campaign was eventually performed at different operating regimes according to the ESC procedure and investigated the recovery potential of the power unit at design and off-design conditions. Mechanical power recovered ranged from 0.7 kW up to 1.9 kW, with an overall cycle efficiency from 3.8% up to 4.8% respectively. These results candidate sliding vane machines as efficient and reliable devices for waste heat recovery applications.

Discrete element modeling of the mass movement and loose material supplying the gully process of a debris avalanche in the Bayi Gully, Southwest China

NASA Astrophysics Data System (ADS)

Zhou, Jia-wen; Huang, Kang-xin; Shi, Chong; Hao, Ming-hui; Guo, Chao-xu

2015-03-01

The dynamic process of a debris avalanche in mountainous areas is influenced by the landslide volume, topographical conditions, mass-material composition, mechanical properties and other factors. A good understanding of the mass movement and loose material supplying the gully process is very important for understanding the dynamic properties of debris avalanches. Three-dimensional particle flow code (PFC3D) was used to simulate a debris avalanche in Quaternary deposits at the Bayi Gully, Southwest China. FORTRAN and AutoCAD were used for the secondary development to display the mass movement process and to quantitatively describe the mass movement and loose material supplying the gully process. The simulated results show that after the landslide is initiated, the gravitational potential energy is converted into kinetic energy with a variation velocity for the sliding masses. Two stages exist for the average-movement velocity: the acceleration stage and the slowdown stage, which are influenced by the topographical conditions. For the loose materials supplying the gully process, the cumulative volume of the sliding masses into the gully gradually increases over the time. When the landslide volume is not large enough, the increasing landslide volume does not obviously influence the movement process of the sliding masses. The travel distance and movement velocity increase with the decreasing numerical parameters, and the mass-movement process is finished more quickly using low-value parameters. The deposition area of the sliding masses decreases with the increasing numerical parameters and the corresponding deposition thickness increases. The mass movement of the debris avalanche is not only influenced by the mechanical parameters but is also controlled by the topographical conditions.

Variability in Pathologists’ Interpretations of Individual Breast Biopsy Slides: A Population Perspective

PubMed Central

Elmore, Joann G.; Nelson, Heidi D.; Pepe, Margaret S.; Longton, Gary M.; Tosteson, Anna N.A.; Geller, Berta; Onega, Tracy; Carney, Patricia A.; Jackson, Sara L.; Allison, Kimberly H.; Weaver, Donald L.

2016-01-01

Background The effect of physician diagnostic variability on accuracy at a population level depends on the prevalence of diagnoses. Objective To estimate how diagnostic variability affects accuracy from the perspective of a U.S. woman aged 50 to 59 years having a breast biopsy. Design Applied probability using Bayes theorem. Setting B-Path (Breast Pathology) Study comparing pathologists’ interpretations of a single biopsy slide versus a reference consensus interpretation from 3 experts. Participants 115 practicing pathologists (6900 total interpretations from 240 distinct cases). Measurements A single representative slide from each of the 240 cases was used to estimate the proportion of biopsies with a diagnosis that would be verified if the same slide were interpreted by a reference group of 3 expert pathologists. Probabilities of confirmation (predictive values) were estimated using B-Path Study results and prevalence of biopsy diagnoses for women aged 50 to 59 years in the Breast Cancer Surveillance Consortium. Results Overall, if 1 representative slide were used per case, 92.3% (95% CI, 91.4% to 93.1%) of breast biopsy diagnoses would be verified by reference consensus diagnoses, with 4.6% (CI, 3.9% to 5.3%) overinterpreted and 3.2% (CI, 2.7% to 3.6%) underinterpreted. Verification of invasive breast cancer and benign without atypia diagnoses is highly probable; estimated predictive values were 97.7% (CI, 96.5% to 98.7%) and 97.1% (CI, 96.7% to 97.4%), respectively. Verification is less probable for atypia (53.6% overinterpreted and 8.6% underinterpreted) and ductal carcinoma in situ (DCIS) (18.5% overinterpreted and 11.8% underinterpreted). Limitations Estimates are based on a testing situation with 1 slide used per case and without access to second opinions. Population-adjusted estimates may differ for women from other age groups, unscreened women, or women in different practice settings. Conclusion This analysis, based on interpretation of a single breast biopsy slide per case, predicts a low likelihood that a diagnosis of atypia or DCIS would be verified by a reference consensus diagnosis. This diagnostic gray zone should be considered in clinical management decisions in patients with these diagnoses. Primary Funding Source National Cancer Institute. PMID:26999810

Mouse cursor movement and eye tracking data as an indicator of pathologists’ attention when viewing digital whole slide images

PubMed Central

Raghunath, Vignesh; Braxton, Melissa O.; Gagnon, Stephanie A.; Brunyé, Tad T.; Allison, Kimberly H.; Reisch, Lisa M.; Weaver, Donald L.; Elmore, Joann G.; Shapiro, Linda G.

2012-01-01

Context: Digital pathology has the potential to dramatically alter the way pathologists work, yet little is known about pathologists’ viewing behavior while interpreting digital whole slide images. While tracking pathologist eye movements when viewing digital slides may be the most direct method of capturing pathologists’ viewing strategies, this technique is cumbersome and technically challenging to use in remote settings. Tracking pathologist mouse cursor movements may serve as a practical method of studying digital slide interpretation, and mouse cursor data may illuminate pathologists’ viewing strategies and time expenditures in their interpretive workflow. Aims: To evaluate the utility of mouse cursor movement data, in addition to eye-tracking data, in studying pathologists’ attention and viewing behavior. Settings and Design: Pathologists (N = 7) viewed 10 digital whole slide images of breast tissue that were selected using a random stratified sampling technique to include a range of breast pathology diagnoses (benign/atypia, carcinoma in situ, and invasive breast cancer). A panel of three expert breast pathologists established a consensus diagnosis for each case using a modified Delphi approach. Materials and Methods: Participants’ foveal vision was tracked using SensoMotoric Instruments RED 60 Hz eye-tracking system. Mouse cursor movement was tracked using a custom MATLAB script. Statistical Analysis Used: Data on eye-gaze and mouse cursor position were gathered at fixed intervals and analyzed using distance comparisons and regression analyses by slide diagnosis and pathologist expertise. Pathologists’ accuracy (defined as percent agreement with the expert consensus diagnoses) and efficiency (accuracy and speed) were also analyzed. Results: Mean viewing time per slide was 75.2 seconds (SD = 38.42). Accuracy (percent agreement with expert consensus) by diagnosis type was: 83% (benign/atypia); 48% (carcinoma in situ); and 93% (invasive). Spatial coupling was close between eye-gaze and mouse cursor positions (highest frequency ∆x was 4.00px (SD = 16.10), and ∆y was 37.50px (SD = 28.08)). Mouse cursor position moderately predicted eye gaze patterns (Rx = 0.33 and Ry = 0.21). Conclusions: Data detailing mouse cursor movements may be a useful addition to future studies of pathologists’ accuracy and efficiency when using digital pathology. PMID:23372984

Online frequency estimation with applications to engine and generator sets

NASA Astrophysics Data System (ADS)

Manngård, Mikael; Böling, Jari M.

2017-07-01

Frequency and spectral analysis based on the discrete Fourier transform is a fundamental task in signal processing and machine diagnostics. This paper aims at presenting computationally efficient methods for real-time estimation of stationary and time-varying frequency components in signals. A brief survey of the sliding time window discrete Fourier transform and Goertzel filter is presented, and two filter banks consisting of: (i) sliding time window Goertzel filters (ii) infinite impulse response narrow bandpass filters are proposed for estimating instantaneous frequencies. The proposed methods show excellent results on both simulation studies and on a case study using angular speed data measurements of the crankshaft of a marine diesel engine-generator set.

Turbocharger with sliding piston, and having vanes and leakage dams

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

Roberts, Quentin; Alnega, Ahmed

2011-12-06

A turbocharger having a sliding piston for regulating exhaust gas flow into the turbine wheel includes a set of first vanes mounted on a fixed first wall of the turbine nozzle and projecting axially toward an opposite second wall of the nozzle, and/or a set of second vanes mounted on the end of the piston and projecting in an opposite axial direction toward the first wall of the nozzle. For the/each set of vanes, there are leakage dams formed on the wall that is adjacent the vane tips when the piston is closed. The leakage dams are closely adjacent themore » vane tips and discourage exhaust gas from leaking in a generally radial direction past the vane tips as the piston just begins to open from its fully closed position.« less

A Randomized Study Comparing Digital Imaging to Traditional Glass Slide Microscopy for Breast Biopsy and Cancer Diagnosis.

PubMed

Elmore, Joann G; Longton, Gary M; Pepe, Margaret S; Carney, Patricia A; Nelson, Heidi D; Allison, Kimberly H; Geller, Berta M; Onega, Tracy; Tosteson, Anna N A; Mercan, Ezgi; Shapiro, Linda G; Brunyé, Tad T; Morgan, Thomas R; Weaver, Donald L

2017-01-01

Digital whole slide imaging may be useful for obtaining second opinions and is used in many countries. However, the U.S. Food and Drug Administration requires verification studies. Pathologists were randomized to interpret one of four sets of breast biopsy cases during two phases, separated by ≥9 months, using glass slides or digital format (sixty cases per set, one slide per case, n = 240 cases). Accuracy was assessed by comparing interpretations to a consensus reference standard. Intraobserver reproducibility was assessed by comparing the agreement of interpretations on the same cases between two phases. Estimated probabilities of confirmation by a reference panel (i.e., predictive values) were obtained by incorporating data on the population prevalence of diagnoses. Sixty-five percent of responding pathologists were eligible, and 252 consented to randomization; 208 completed Phase I (115 glass, 93 digital); and 172 completed Phase II (86 glass, 86 digital). Accuracy was slightly higher using glass compared to digital format and varied by category: invasive carcinoma, 96% versus 93% ( P = 0.04); ductal carcinoma in situ (DCIS), 84% versus 79% ( P < 0.01); atypia, 48% versus 43% ( P = 0.08); and benign without atypia, 87% versus 82% ( P < 0.01). There was a small decrease in intraobserver agreement when the format changed compared to when glass slides were used in both phases ( P = 0.08). Predictive values for confirmation by a reference panel using glass versus digital were: invasive carcinoma, 98% and 97% (not significant [NS]); DCIS, 70% and 57% ( P = 0.007); atypia, 38% and 28% ( P = 0.002); and benign without atypia, 97% and 96% (NS). In this large randomized study, digital format interpretations were similar to glass slide interpretations of benign and invasive cancer cases. However, cases in the middle of the spectrum, where more inherent variability exists, may be more problematic in digital format. Future studies evaluating the effect these findings exert on clinical practice and patient outcomes are required.

Registration of organs with sliding interfaces and changing topologies

NASA Astrophysics Data System (ADS)

Berendsen, Floris F.; Kotte, Alexis N. T. J.; Viergever, Max A.; Pluim, Josien P. W.

2014-03-01

Smoothness and continuity assumptions on the deformation field in deformable image registration do not hold for applications where the imaged objects have sliding interfaces. Recent extensions to deformable image registration that accommodate for sliding motion of organs are limited to sliding motion along approximately planar surfaces or cannot model sliding that changes the topological configuration in case of multiple organs. We propose a new extension to free-form image registration that is not limited in this way. Our method uses a transformation model that consists of uniform B-spline transformations for each organ region separately, which is based on segmentation of one image. Since this model can create overlapping regions or gaps between regions, we introduce a penalty term that minimizes this undesired effect. The penalty term acts on the surfaces of the organ regions and is optimized simultaneously with the image similarity. To evaluate our method registrations were performed on publicly available inhale-exhale CT scans for which performances of other methods are known. Target registration errors are computed on dense landmark sets that are available with these datasets. On these data our method outperforms the other methods in terms of target registration error and, where applicable, also in terms of overlap and gap volumes. The approximation of the other methods of sliding motion along planar surfaces is reasonably well suited for the motion present in the lung data. The ability of our method to handle sliding along curved boundaries and for changing region topology configurations was demonstrated on synthetic images.

Robust sliding-window reconstruction for Accelerating the acquisition of MR fingerprinting.

PubMed

Cao, Xiaozhi; Liao, Congyu; Wang, Zhixing; Chen, Ying; Ye, Huihui; He, Hongjian; Zhong, Jianhui

2017-10-01

To develop a method for accelerated and robust MR fingerprinting (MRF) with improved image reconstruction and parameter matching processes. A sliding-window (SW) strategy was applied to MRF, in which signal and dictionary matching was conducted between fingerprints consisting of mixed-contrast image series reconstructed from consecutive data frames segmented by a sliding window, and a precalculated mixed-contrast dictionary. The effectiveness and performance of this new method, dubbed SW-MRF, was evaluated in both phantom and in vivo. Error quantifications were conducted on results obtained with various settings of SW reconstruction parameters. Compared with the original MRF strategy, the results of both phantom and in vivo experiments demonstrate that the proposed SW-MRF strategy either provided similar accuracy with reduced acquisition time, or improved accuracy with equal acquisition time. Parametric maps of T 1 , T 2 , and proton density of comparable quality could be achieved with a two-fold or more reduction in acquisition time. The effect of sliding-window width on dictionary sensitivity was also estimated. The novel SW-MRF recovers high quality image frames from highly undersampled MRF data, which enables more robust dictionary matching with reduced numbers of data frames. This time efficiency may facilitate MRF applications in time-critical clinical settings. Magn Reson Med 78:1579-1588, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

Optimizing inpatient glycemic control with basal-bolus insulin therapy.

PubMed

Pollom, R Daniel

2010-11-01

Hyperglycemia is highly prevalent in the acute-care setting and is associated with an increased risk of morbidity and mortality. Evidence suggests that glycemic control in this population is suboptimal, due in part to continued use of nonphysiologic sliding-scale insulin strategies without scheduled basal insulin doses or prandial insulin with concomitant correction doses. Although the ineffectiveness and risks of sliding-scale insulin regimens have been criticized for decades, sliding-scale insulin is still the most commonly prescribed subcutaneous insulin regimen among inpatients. Improving inpatient management requires the use of scheduled basal-bolus insulin therapy that includes basal insulin, nutritional insulin, and supplemental, or correctional, insulin. Insulin analogs are the preferred insulins, as they provide a more physiologic action than human insulin regimens, are associated with a lower risk of hypoglycemia, and are more convenient to administer than human insulins. Standardized insulin protocols and subcutaneous insulin order sets are critical components of effective inpatient glycemic control. Although preliminary data have demonstrated that inpatient diabetes management programs involving basal-bolus insulin therapy are effective and well tolerated, more research is needed.

Vehicle detection in aerial surveillance using dynamic Bayesian networks.

PubMed

Cheng, Hsu-Yung; Weng, Chih-Chia; Chen, Yi-Ying

2012-04-01

We present an automatic vehicle detection system for aerial surveillance in this paper. In this system, we escape from the stereotype and existing frameworks of vehicle detection in aerial surveillance, which are either region based or sliding window based. We design a pixelwise classification method for vehicle detection. The novelty lies in the fact that, in spite of performing pixelwise classification, relations among neighboring pixels in a region are preserved in the feature extraction process. We consider features including vehicle colors and local features. For vehicle color extraction, we utilize a color transform to separate vehicle colors and nonvehicle colors effectively. For edge detection, we apply moment preserving to adjust the thresholds of the Canny edge detector automatically, which increases the adaptability and the accuracy for detection in various aerial images. Afterward, a dynamic Bayesian network (DBN) is constructed for the classification purpose. We convert regional local features into quantitative observations that can be referenced when applying pixelwise classification via DBN. Experiments were conducted on a wide variety of aerial videos. The results demonstrate flexibility and good generalization abilities of the proposed method on a challenging data set with aerial surveillance images taken at different heights and under different camera angles.

Foliated breccias in the active Portuguese Bend landslide complex, California: bearing on melange genesis

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

Larue, D.K.; Hudleston, P.J.

1987-05-01

The active portion of the Portuguese Bend landslide complex is approximately 3 km/sup 2/ in area and 30-50 m thick. Measured displacement rates range from less than one to greater than 30 mm/day on different parts of the landslide, with total displacements over the last 30 yrs ranging from about 10 to greater than 150 m. Six types of breccia, each locally with a foliated matrix, were recognized in the active landslide complex and are absent outside the landslide complex. Slide-body breccias are of two types, the first formed by extensional fracturing during bulk pure shear at the top ofmore » the landslide (slide-top breccia) and the second by flow of tuffaceous shales and fracture of embedded siliceous shales during simple shear deep in the landslide to the basal decollement (slide-bottom breccias). Slide-margin breccias, also in simple shear, are produced on the lateral margins of individual slide blocks accompanying wrench-fault motion. Other breccias (fault-ramp breccias) are formed during motion over ramps. Colluvial deposits within tension gashes (crack-fill breccias) and at the toe of the slide (slide-toe breccias) represent a fifth breccia type. Diapirs originating from over-pressured zones at the slide base also contain breccia. Recognition of different breccia types in ancient rocks would be difficult, because fabrics in the different types are similar. Foliations are defined by: scaly cleavage, compositional banding and color banding (in shear zones), stretched mud clasts, and aligned hard grains. Foliated breccias are synonymous with melanges. The authors regard the six breccia types described herein as representing the principal types of melange that occur in ancient accretionary settings.« less

Information Systems Plan.

DTIC Science & Technology

1985-04-01

increase in load factors. CURENUT YEARLY COST OF INFOR TION MANAGEK1KUT 0.04 FTE’s $876 DATA SET: Natural Resource (Management) VINAGE .QUIRRmuT OF...OF DATA SITS NEEDED TO SUPPORT IDENTIFIED DISTRICT PROCESSES PXOCESSz 53 - Provide Audio-Visual Services DATA SET: Equipment (Slide File) VINAG

Data-Driven Haptic Modeling and Rendering of Viscoelastic and Frictional Responses of Deformable Objects.

PubMed

Yim, Sunghoon; Jeon, Seokhee; Choi, Seungmoon

2016-01-01

In this paper, we present an extended data-driven haptic rendering method capable of reproducing force responses during pushing and sliding interaction on a large surface area. The main part of the approach is a novel input variable set for the training of an interpolation model, which incorporates the position of a proxy - an imaginary contact point on the undeformed surface. This allows us to estimate friction in both sliding and sticking states in a unified framework. Estimating the proxy position is done in real-time based on simulation using a sliding yield surface - a surface defining a border between the sliding and sticking regions in the external force space. During modeling, the sliding yield surface is first identified via an automated palpation procedure. Then, through manual palpation on a target surface, input data and resultant force data are acquired. The data are used to build a radial basis interpolation model. During rendering, this input-output mapping interpolation model is used to estimate force responses in real-time in accordance with the interaction input. Physical performance evaluation demonstrates that our approach achieves reasonably high estimation accuracy. A user study also shows plausible perceptual realism under diverse and extensive exploration.

Calculation of Non-Bonded Forces Due to Sliding of Bundled Carbon Nanotubes

NASA Technical Reports Server (NTRS)

Frankland, S. J. V.; Bandorawalla, T.; Gates, T. S.

2003-01-01

An important consideration for load transfer in bundles of single-walled carbon nanotubes is the nonbonded (van der Waals) forces between the nanotubes and their effect on axial sliding of the nanotubes relative to each other. In this research, the non-bonded forces in a bundle of seven hexagonally packed (10,10) single-walled carbon nanotubes are represented as an axial force applied to the central nanotube. A simple model, based on momentum balance, is developed to describe the velocity response of the central nanotube to the applied force. The model is verified by comparing its velocity predictions with molecular dynamics simulations that were performed on the bundle with different force histories applied to the central nanotube. The model was found to quantitatively predict the nanotube velocities obtained from the molecular dynamics simulations. Both the model and the simulations predict a threshold force at which the nanotube releases from the bundle. This force converts to a shear yield strength of 10.5-11.0 MPa for (10,10) nanotubes in a bundle.

Modern Instrumentation of a Historical Landslide to Understand Dynamic Processes Governing Slope Movement in a Hostile Environment.

NASA Astrophysics Data System (ADS)

Johnson, K. A.

2017-12-01

The Milepost 6.2 Landslide on Many Glacier Road in Glacier National Park, Montana, has been moving since construction of the roadway in the early 1900's. Movement of the slide has a direct impact on Park operations and requires regrading and reconstruction of the road on a nearly annual basis. Prior attempts to stabilize the slope were not effective. Despite the history of this slide, very little quality data was available to delineate the depth and shape of the slide or the groundwater pressures that influence slope stability due to only seasonal data collection and a hostile winter environment. Landslide dynamics are further complicated where the toe of the slide becomes submerged seasonally by Lake Sherburne. In addition, due to irrigation use the lake levels fluctuate rapidly with seasonal rise and drops commonly greater than 30 feet in elevation. Five Shape Accelerometer Array inclinometers (SAAs) were installed to depths between 60 and 200 feet, along with 10 vibrating wire piezometers, one tipping bucket rain gauge, and onsite data acquisition system with a real-time satellite communication link enabling year-round data collection. Measurements of groundwater pressures and slide dynamics were used to develop a well constrained 2-D dynamic model of slide movement. Movement is controlled by clayey zones in glacial till deposits that mantle the valley slopes, along with water pressures from groundwater in the slope and fluctuating lake levels at the toe of the slope. The SAAs document slide plane locations and rates of slide movement as it changes through the year in response to the dynamic hydrologic setting. SAAs document sliding of over 3 feet and continue to operate and generate additional data. The data collected enabled the design of an extensive horizontal drain system to lower the groundwater pressures and stabilize the slope. Continuous year-round monitoring allowed comparison of slope movement in response to changes in lake elevation and precipitation events.

An LED Approach for Measuring the Photocatalytic Breakdown of Crystal Violet Dye

NASA Technical Reports Server (NTRS)

Ryan, Robert E.; Underwood, Lauren W.; ONeal, Duane; Pagnutti, Mary; Davis, Bruce A.

2009-01-01

A simple technique to assess the reactivity of photocatalytic coatings sprayed onto transmissive glass surfaces was developed. This new method uses ultraviolet (UV) gallium nitride (GaN) light-emitting diodes (LEDs) to drive a photocatalytic reaction (the photocatalytic breakdown of a UV-resistant dye applied to a surface coated with the semiconductor titanium dioxide); and then a combination of a stabilized white light LED and a spectrometer to track the dye degradation as a function of time. Simple, standardized evaluation techniques that assess photocatalytic materials over a variety of environmental conditions, including illumination level, are not generally available and are greatly needed prior to in situ application of photocatalytic technologies. To date, much research pertaining to this aspect of photocatalysis has been limited and has focused primarily on laboratory experiments using mercury lamps. Mercury lamp illumination levels are difficult to control over large ranges and are temporally modulated by line power, limiting their use in helping to understand and predict how photocatalytic materials will behave in natural environmental settings and conditions. The methodology described here, using steady-state LEDs and time series spectroradiometric techniques, is a novel approach to explore the effect of UV light on the photocatalytic degradation of a UV resistant dye (crystal violet). GaN UV LED arrays, centered around 365 nm with an adjustable DC power supply, are used to create a small, spatially uniform light field where the steady state light level can be varied over three to four orders of magnitude. For this study, a set of glass microscope slides was custom coated with a thinly sprayed layer of photocatalytic titanium dioxide. Crystal violet was then applied to these titanium-dioxide coated slides and to uncoated control slides. The slides were then illuminated at various light levels from the dye side of the slide by the UV LED array. To monitor dye degradation on the slides over time, a temperature-stabilized white light LED was used to illuminate the opposite side of the slides. As the dye degraded, the amount of light from the white light LED transmitted through the slide was monitored with a spectrometer and subsequently analyzed to determine and compare the rate of dye degradation for photocatalytically coated versus uncoated slide surfaces. The long-term stability of the spectrometer/white light LED combination, which required only a single reference spectra to be taken for a time series sequence of several hours, enabled accurate measurements of transmitted light over time. Time series transmission curves were generated and results demonstrated that over time the transmission increased much more rapidly on the coated slides than on the control slides. This experimental configuration and methodology for photocatalytic activity measurement minimizes many external variable effects and allows low light level studies to be performed. This study also compares the advantages of this novel LED light source design to traditional mercury lamp systems and non-LED lamp approaches that have conventionally been used. The methodology and experimental design research summarized in this abstract is partly funded by the Department of Homeland Security, Science and Technology Directorate, and by the NASA Stennis Space Center Innovative Partnerships Program.

AV Corner.

ERIC Educational Resources Information Center

Berry, Donna A., Ed.

1990-01-01

Reviewed are two 35MM slide sets "Halley's Comet Revealed" and "Supernova 1987A"; and a videotape entitled "Experiments; Physics Level 1. Magnetic Fields." Features, availability, strengths and weaknesses are discussed. (CW)

Direct Torque Control of a Small Wind Turbine with a Sliding-Mode Speed Controller

NASA Astrophysics Data System (ADS)

Sri Lal Senanayaka, Jagath; Karimi, Hamid Reza; Robbersmyr, Kjell G.

2016-09-01

In this paper. the method of direct torque control in the presence of a sliding-mode speed controller is proposed for a small wind turbine being used in water heating applications. This concept and control system design can be expanded to grid connected or off-grid applications. Direct torque control of electrical machines has shown several advantages including very fast dynamics torque control over field-oriented control. Moreover. the torque and flux controllers in the direct torque control algorithms are based on hvsteretic controllers which are nonlinear. In the presence of a sliding-mode speed control. a nonlinear control system can be constructed which is matched for AC/DC conversion of the converter that gives fast responses with low overshoots. The main control objectives of the proposed small wind turbine can be maximum power point tracking and soft-stall power control. This small wind turbine consists of permanent magnet synchronous generator and external wind speed. and rotor speed measurements are not required for the system. However. a sensor is needed to detect the rated wind speed overpass events to activate proper speed references for the wind turbine. Based on the low-cost design requirement of small wind turbines. an available wind speed sensor can be modified. or a new sensor can be designed to get the required measurement. The simulation results will be provided to illustrate the excellent performance of the closed-loop control system in entire wind speed range (4-25 m/s).

Effect of Intraoral Aging on Debris Accumulation and Friction of First Molar Tubes.

PubMed

Chaptini, Edmond; Khoury, Elie; Cacciafesta, Vittorio; Naaman, Nada

2016-11-01

The aim of this article was to evaluate the impact of intraoral aging and site specificity on debris accumulation and friction in molar tubes after intraoral use. A total of 80 intraorally used first molar convertible tubes were provided by 20 orthodontic adolescent patients after 6 months of treatment. The specimens were divided into eight groups (n = 10) according to the mouth quadrant and the type of examination [four groups of ten tubes for scanning electron microscope (SEM) and four groups of ten tubes for friction test]. Scanning electron microscope examination was performed after opening the convertible caps and friction test was executed using a 0.019'' × 0.025'' stainless steel wire, which was inserted in the tubes belonging to each group. The Mann-Whitney test, analysis of variance (ANOVA), and Bonferroni tests were performed for statistical analysis at 0.01 level of significance. There was a significant increase in the amount of debris and frictional force after 6 months of intraoral exposure (p < 0.0001). Debris scores were higher (10% increase) on the upper tubes when compared with the lower ones, with no statistical difference. Mean frictional force ranged from 0.22 to 0.26 N according to the mouth quadrant, but the difference between groups was also not significant. After 6 months of intraoral exposure, there was a significant increase in the amount of debris in the first molar tube slots, leading to significantly higher frictional forces during sliding mechanics. The influence of site specificity on the amount of debris and on frictional forces of the first molar tubes could not be demonstrated. Molar tubes should be cleaned, before and during sliding mechanics, in order to minimize friction.

A data model and database for high-resolution pathology analytical image informatics.

PubMed

Wang, Fusheng; Kong, Jun; Cooper, Lee; Pan, Tony; Kurc, Tahsin; Chen, Wenjin; Sharma, Ashish; Niedermayr, Cristobal; Oh, Tae W; Brat, Daniel; Farris, Alton B; Foran, David J; Saltz, Joel

2011-01-01

The systematic analysis of imaged pathology specimens often results in a vast amount of morphological information at both the cellular and sub-cellular scales. While microscopy scanners and computerized analysis are capable of capturing and analyzing data rapidly, microscopy image data remain underutilized in research and clinical settings. One major obstacle which tends to reduce wider adoption of these new technologies throughout the clinical and scientific communities is the challenge of managing, querying, and integrating the vast amounts of data resulting from the analysis of large digital pathology datasets. This paper presents a data model, which addresses these challenges, and demonstrates its implementation in a relational database system. This paper describes a data model, referred to as Pathology Analytic Imaging Standards (PAIS), and a database implementation, which are designed to support the data management and query requirements of detailed characterization of micro-anatomic morphology through many interrelated analysis pipelines on whole-slide images and tissue microarrays (TMAs). (1) Development of a data model capable of efficiently representing and storing virtual slide related image, annotation, markup, and feature information. (2) Development of a database, based on the data model, capable of supporting queries for data retrieval based on analysis and image metadata, queries for comparison of results from different analyses, and spatial queries on segmented regions, features, and classified objects. The work described in this paper is motivated by the challenges associated with characterization of micro-scale features for comparative and correlative analyses involving whole-slides tissue images and TMAs. Technologies for digitizing tissues have advanced significantly in the past decade. Slide scanners are capable of producing high-magnification, high-resolution images from whole slides and TMAs within several minutes. Hence, it is becoming increasingly feasible for basic, clinical, and translational research studies to produce thousands of whole-slide images. Systematic analysis of these large datasets requires efficient data management support for representing and indexing results from hundreds of interrelated analyses generating very large volumes of quantifications such as shape and texture and of classifications of the quantified features. We have designed a data model and a database to address the data management requirements of detailed characterization of micro-anatomic morphology through many interrelated analysis pipelines. The data model represents virtual slide related image, annotation, markup and feature information. The database supports a wide range of metadata and spatial queries on images, annotations, markups, and features. We currently have three databases running on a Dell PowerEdge T410 server with CentOS 5.5 Linux operating system. The database server is IBM DB2 Enterprise Edition 9.7.2. The set of databases consists of 1) a TMA database containing image analysis results from 4740 cases of breast cancer, with 641 MB storage size; 2) an algorithm validation database, which stores markups and annotations from two segmentation algorithms and two parameter sets on 18 selected slides, with 66 GB storage size; and 3) an in silico brain tumor study database comprising results from 307 TCGA slides, with 365 GB storage size. The latter two databases also contain human-generated annotations and markups for regions and nuclei. Modeling and managing pathology image analysis results in a database provide immediate benefits on the value and usability of data in a research study. The database provides powerful query capabilities, which are otherwise difficult or cumbersome to support by other approaches such as programming languages. Standardized, semantic annotated data representation and interfaces also make it possible to more efficiently share image data and analysis results.

Pure moment testing for spinal biomechanics applications: Fixed versus sliding ring cable-driven test designs.

PubMed

Eguizabal, Johnny; Tufaga, Michael; Scheer, Justin K; Ames, Christopher; Lotz, Jeffrey C; Buckley, Jenni M

2010-05-07

In vitro multi-axial bending testing using pure moment loading conditions has become the standard in evaluating the effects of different types of surgical intervention on spinal kinematics. Simple, cable-driven experimental set-ups have been widely adopted because they require little infrastructure. Traditionally, "fixed ring" cable-driven experimental designs have been used; however, there have been concerns with the validity of this set-up in applying pure moment loading. This study involved directly comparing the loading state induced by a traditional "fixed ring" apparatus versus a novel "sliding ring" approach. Flexion-extension bending was performed on an artificial spine model and a single cadaveric test specimen, and the applied loading conditions to the specimen were measured with an in-line multiaxial load cell. The results showed that the fixed ring system applies flexion-extension moments that are 50-60% less than the intended values. This design also imposes non-trivial anterior-posterior shear forces, and non-uniform loading conditions were induced along the length of the specimen. The results of this study indicate that fixed ring systems have the potential to deviate from a pure moment loading state and that our novel sliding ring modification corrects this error in the original test design. This suggests that the proposed sliding ring design should be used for future in vitro spine biomechanics studies involving a cable-driven pure moment apparatus. Copyright 2010 Elsevier Ltd. All rights reserved.

Potential effects of gas hydrate on human welfare

USGS Publications Warehouse

Kvenvolden, K.A.

1999-01-01

For almost 30 years, serious interest has been directed toward natural gas hydrate, a crystalline solid composed of water and methane, as a potential (i) energy resource, (ii) factor in global climate change, and (iii) sub-marine geohazard. Although each of these issues can affect human welfare, only (iii) is considered to be of immediate importance. Assessments of gas hydrate as an energy resource have often been overly optimistic, based in part on its very high methane content and on its worldwide occurrence in continental margins. Although these attributes are attractive, geologic settings, reservoir properties, and phase-equilibria considerations diminish the energy resource potential of natural gas hydrate. The possible role of gas hydrate in global climate change has been often overstated. Although methane is a 'greenhouse' gas in the atmosphere, much methane from dissociated gas hydrate may never reach the atmosphere, but rather may be converted to carbon dioxide and sequestered by the hydrosphere/biosphere before reaching the atmosphere. Thus, methane from gas hydrate may have little opportunity to affect global climate change. However, submarine geohazards (such as sediment instabilities and slope failures on local and regional scales, leading to debris flows, slumps, slides, and possible tsunamis) caused by gas-hydrate dissociation are of immediate and increasing importance as humankind moves to exploit seabed resources in ever-deepening waters of coastal oceans. The vulnerability of gas hydrate to temperature and sea level changes enhances the instability of deep-water oceanic sediments, and thus human activities and installations in this setting can be affected.

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

Bajric, Sendin

These are a set of slides that give the personal background of the author, information about his LANL organization, and information about his internship project at LANL about additive manufacturing and selective laser sintering (SLS).

Operation strategy for grid-tied DC-coupling power converter interface integrating wind/solar/battery

NASA Astrophysics Data System (ADS)

Jou, H. L.; Wu, J. C.; Lin, J. H.; Su, W. N.; Wu, T. S.; Lin, Y. T.

2017-11-01

The operation strategy for a small-capacity grid-tied DC-coupling power converter interface (GDPCI) integrating wind energy, solar energy and battery energy storage is proposed. The GDPCI is composed of a wind generator, a solar module set a battery bank, a boost DC-DC power converter (DDPC), a bidirectional DDPC power converter, an AC-DC power converter (ADPC) and a five-level DC-AC inverter (DAI). A solar module set, a wind generator and a battery bank are coupled to the common DC bus through the boost DDPC, the ADPC and the bidirectional DDPC, respectively. For verifying the performance of the GDPCI under different operation modes, computer simulation is carried out by PSIM.

40 CFR 459.11 - Specialized definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... definitions, abbreviations and methods of analysis set forth in part 401 of this chapter shall apply to this... as paper prints, slides, negatives, enlargements, movie film and other sensitized materials. ...

A Randomized Study Comparing Digital Imaging to Traditional Glass Slide Microscopy for Breast Biopsy and Cancer Diagnosis

PubMed Central

Elmore, Joann G.; Longton, Gary M.; Pepe, Margaret S.; Carney, Patricia A.; Nelson, Heidi D.; Allison, Kimberly H.; Geller, Berta M.; Onega, Tracy; Tosteson, Anna N. A.; Mercan, Ezgi; Shapiro, Linda G.; Brunyé, Tad T.; Morgan, Thomas R.; Weaver, Donald L.

2017-01-01

Background: Digital whole slide imaging may be useful for obtaining second opinions and is used in many countries. However, the U.S. Food and Drug Administration requires verification studies. Methods: Pathologists were randomized to interpret one of four sets of breast biopsy cases during two phases, separated by ≥9 months, using glass slides or digital format (sixty cases per set, one slide per case, n = 240 cases). Accuracy was assessed by comparing interpretations to a consensus reference standard. Intraobserver reproducibility was assessed by comparing the agreement of interpretations on the same cases between two phases. Estimated probabilities of confirmation by a reference panel (i.e., predictive values) were obtained by incorporating data on the population prevalence of diagnoses. Results: Sixty-five percent of responding pathologists were eligible, and 252 consented to randomization; 208 completed Phase I (115 glass, 93 digital); and 172 completed Phase II (86 glass, 86 digital). Accuracy was slightly higher using glass compared to digital format and varied by category: invasive carcinoma, 96% versus 93% (P = 0.04); ductal carcinoma in situ (DCIS), 84% versus 79% (P < 0.01); atypia, 48% versus 43% (P = 0.08); and benign without atypia, 87% versus 82% (P < 0.01). There was a small decrease in intraobserver agreement when the format changed compared to when glass slides were used in both phases (P = 0.08). Predictive values for confirmation by a reference panel using glass versus digital were: invasive carcinoma, 98% and 97% (not significant [NS]); DCIS, 70% and 57% (P = 0.007); atypia, 38% and 28% (P = 0.002); and benign without atypia, 97% and 96% (NS). Conclusions: In this large randomized study, digital format interpretations were similar to glass slide interpretations of benign and invasive cancer cases. However, cases in the middle of the spectrum, where more inherent variability exists, may be more problematic in digital format. Future studies evaluating the effect these findings exert on clinical practice and patient outcomes are required. PMID:28382226

Observed Variability of Tsunamigenic Potential of Enormous Submarine Landslides Explained Through Modeling - A Comparison of the Holocene Storegga and Trænadjupet Events.

NASA Astrophysics Data System (ADS)

Løvholt, F.; Kim, J.; Laberg, J. S.

2016-12-01

The continental margin offshore Norway have experienced a range of giant submarine landslides having volumes ranging from hundreds to thousands of km3. The most recent and well documented of these events, are the 4500 BP Trænadjupet and the 8100 BP Storegga landslides. Both of these landslides are clay-rich, and involve common features such as retrogressive mass and momentum release mechanisms and weak layers that affect the tsunami generation. The retrogressive behaviour involved the release of several slide blocks which made the multistage failure and landslide evolution complex. The Storegga Slide reveals a rich and well documented onshore footprint in terms of paleotsunami deposits along the coastlines of Denmark, UK, the Faroe Islands, and Norway. In striking contrast, there exists no firm evidence of similar paleotsunami deposits from the younger Trænadjupet landslide. Here, we use a suit of new retrogressive and viscoplastic landslide models to simulate the run-out of both of these landslide events, and then couple the landslide to dispersive tsunami models. By using the new landslide models, we are able to obtain a better agreement with the observed paleotsunami deposits from the Storegga Slide compared to previous studies, and at the same time, to link the results to a landslide model that comply better with the slide morphology. Using the landslide model and soil parameters established for the Storegga Slide as the starting point, we set up a similar set of model scenarios for the Trænadjupet Slide. We discuss how the scenarios for the Trænadjupet landslide with different soil parameters produce different landslide velocities and tsunami heights. We then compare the resulting tsunami heights with constraints from the lack of onshore tsunami observations taking into account the contemporary shoreline position. Finally we briefly discuss the findings from the modeling in terms of both differences in tsunami observations and landslide morphology. The research leading to these results has received funding from the Research Council of Norway under grant number 231252 (Project TsunamiLand) and the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement 603839 (Project ASTARTE).

Resources from the NASA SMD Astrophysics Forum: Addressing the needs of the higher education community (Invited)

NASA Astrophysics Data System (ADS)

Meinke, B. K.; Schultz, G. R.; Smith, D.; Bianchi, L.; Blair, W. P.; Fraknoi, A.

2013-12-01

Four NASA Science Mission Directorate (SMD) Science Education and Public Outreach Forums organize individual SMD-funded E/PO projects and their teams into a coordinated effort. The Forums assist scientists and educators with becoming involved in SMD E/PO and make SMD E/PO resources and expertise accessible to the science and education communities. The Astrophysics Forum and the Astrophysics E/PO community have focused efforts to support and engage the higher education community on enhancing awareness of the resources available to them. To ensure Astrophysics higher education efforts are grounded in audience needs, we held informal conversations with instructors of introductory astronomy courses, convened sessions with higher education faculty and E/PO professionals at conferences, and examined existing literature and findings of the SMD Higher Education Working Group. This work indicates that most Astronomy 101 instructors are not specialists in areas of astrophysics where rapid progress is being made, older textbooks are out of date, and ideas are challenging for students. Instructors are seeking resources and training that support them in effectively teaching the latest science and are in need both basic material and information on new results. In this session, we will discuss our efforts to address these expressed needs, namely through Resource Guides and Slide Sets, and how these are applicable to topics in Heliophysics and Planetary Science. We have collaborated with the Astrophysics E/PO community, researchers, and Astronomy 101 instructors to create two Resource Guides on the topics of cosmology and exoplanets. These fields are ripe with scientific developments that college instructors have told us they find challenging to stay current. Each guide includes a wide variety of sources of background information, links to animations/simulations, classroom activities, and references on teaching each topic. Feedback from Astronomy 101 instructors indicated that the Cosmology Resource Guide is very useful for them and their teaching and that they are very likely to recommend the resource to another instructor. The two guides are available through the ASP website: http://www.astrosociety.org/education/astronomy-resource-guides/ To complement the resource guides, we are developing a series of slide sets to help Astronomy 101 instructors incorporate new discoveries in their classrooms. The 'Astro 101 slide sets' are 5-7 slide presentations on a new development or discovery from a NASA SMD Astrophysics mission relevant to an Astronomy 101 topic. We intend for these slide sets to help Astronomy 101 instructors include new, unfamiliar developments (discoveries not yet in their textbooks) into the 'big-picture' context of the course. With their modular design and non-technical language, the slide sets may also serve audiences beyond Astro101 instruction and are adaptable to different needs. An example on exoplanets will be highlighted in this session. The Astrophysics Forum is supported by NASA under Cooperative Agreement NNX09AQ11A issued by the NASA Science Mission Directorate, and is a partnership between the Space Telescope Science Institute, the Adler Planetarium, the Astronomical Society of the Pacific, and Johns Hopkins University.

The afterlife of the slide: exploring emotional attachment to artefactualised bodily traces.

PubMed

Parry, Bronwyn

2013-01-01

In this paper I explore the role of the slide, not as familiar scientific object, but rather as a fixed remnant that testifies to the lived experience of an individual. Returning to the scene of the public scandal that surrounded the unauthorised retention of children's organs and tissues at two British hospitals in the late 1990s, I investigate the emotional significance that here came to be attached to archived slides. In so doing I draw attention to the ways in which the facticity of the slide--its ability to testify to the fact, or the existence, not only of the person from whom it is drawn, but also, when created for histopathological reasons, the disease that ultimately killed them--acts to efface their presumed ephemerality. In the final section of the paper I turn to consider how the events that I describe have come to shape the ways in which this kind of highly artefactualised bodily material is now accommodated in the institutional setting of the tissue bank and with what implications for research and the wider dissemination of scientific knowledge. Specifically, I explore how and why slides have come to acquire a "personality" and, with it, something akin to legally constituted "personality rights" including rights relating to publicity and privacy.

Measurement of Gear Tooth Dynamic Friction

NASA Technical Reports Server (NTRS)

Rebbechi, Brian; Oswald, Fred B.; Townsend, Dennis P.

1996-01-01

Measurements of dynamic friction forces at the gear tooth contact were undertaken using strain gages at the root fillets of two successive teeth. Results are presented from two gear sets over a range of speeds and loads. The results demonstrate that the friction coefficient does not appear to be significantly influenced by the sliding reversal at the pitch point, and that the friction coefficient values found are in accord with those in general use. The friction coefficient was found to increase at low sliding speeds. This agrees with the results of disc machine testing.

Enterprise Implementation of Digital Pathology: Feasibility, Challenges, and Opportunities.

PubMed

Hartman, D J; Pantanowitz, L; McHugh, J S; Piccoli, A L; OLeary, M J; Lauro, G R

2017-10-01

Digital pathology is becoming technically possible to implement for routine pathology work. At our institution, we have been using digital pathology for second opinion intraoperative consultations for over 10 years. Herein, we describe our experience in converting to a digital pathology platform for primary pathology diagnosis. We implemented an incremental rollout for digital pathology on subspecialty benches, beginning with cases that contained small amounts of tissue (biopsy specimens). We successfully scanned over 40,000 slides through our digital pathology system. Several lessons (both challenges and opportunities) were learned through this implementation. A successful conversion to digital pathology requires pre-imaging adjustments, integrated software and post-imaging evaluations.

A novel application of the MIRC repository in medical education.

PubMed

Roth, Christopher J; Weadock, William J; Dipietro, Michael A

2005-06-01

Medical students on the radiology elective in our institution create electronic presentations to present to each other as part of the requirements for the rotation. Access was given to previous students' presentations via the web-based system, Medical Imaging Resource Center (MIRC) project, created and supported by the Radiological Society of North America (RSNA). RadPix Power 2 MIRC (Weadock Software, LLC, Ann Arbor, MI) software converted the Microsoft PowerPoint (Redmond, WA) presentations to a MIRC-compatible format. The textual information on each slide is searchable across the entire MIRC database. Future students will be able to benefit from the work of their predecessors.

Virtual microscopy: an evaluation of its validity and diagnostic performance in routine histologic diagnosis of skin tumors.

PubMed

Nielsen, Patricia Switten; Lindebjerg, Jan; Rasmussen, Jan; Starklint, Henrik; Waldstrøm, Marianne; Nielsen, Bjarne

2010-12-01

Digitization of histologic slides is associated with many advantages, and its use in routine diagnosis holds great promise. Nevertheless, few articles evaluate virtual microscopy in routine settings. This study is an evaluation of the validity and diagnostic performance of virtual microscopy in routine histologic diagnosis of skin tumors. Our aim is to investigate whether conventional microscopy of skin tumors can be replaced by virtual microscopy. Ninety-six skin tumors and skin-tumor-like changes were consecutively gathered over a 1-week period. Specimens were routinely processed, and digital slides were captured on Mirax Scan (Carl Zeiss MicroImaging, Göttingen, Germany). Four pathologists evaluated the 96 virtual slides and the associated 96 conventional slides twice with intermediate time intervals of at least 3 weeks. Virtual slides that caused difficulties were reevaluated to identify possible reasons for this. The accuracy was 89.2% for virtual microscopy and 92.7% for conventional microscopy. All κ coefficients expressed very good intra- and interobserver agreement. The sensitivities were 85.7% (78.0%-91.0%) and 92.0% (85.5%-95.7%) for virtual and conventional microscopy, respectively. The difference between the sensitivities was 6.3% (0.8%-12.6%). The subsequent reevaluation showed that virtual slides were as useful as conventional slides when rendering a diagnosis. Differences seen are presumed to be due to the pathologists' lack of experience using the virtual microscope. We conclude that it is feasible to make histologic diagnosis on the skin tumor types represented in this study using virtual microscopy after pathologists have completed a period of training. Larger studies should be conducted to verify whether virtual microscopy can replace conventional microscopy in routine practice. Copyright © 2010 Elsevier Inc. All rights reserved.

A Duo of Potassium-Responsive Histidine Kinases Govern the Multicellular Destiny of Bacillus subtilis

PubMed Central

de Oña, Paula; Kunert, Maritta; Leñini, Cecilia; Gallegos-Monterrosa, Ramses; Mhatre, Eisha; Vileta, Darío; Hölscher, Theresa; Kuipers, Oscar P.

2015-01-01

ABSTRACT Multicellular biofilm formation and surface motility are bacterial behaviors considered mutually exclusive. However, the basic decision to move over or stay attached to a surface is poorly understood. Here, we discover that in Bacillus subtilis, the key root biofilm-controlling transcription factor Spo0A~Pi (phosphorylated Spo0A) governs the flagellum-independent mechanism of social sliding motility. A Spo0A-deficient strain was totally unable to slide and colonize plant roots, evidencing the important role that sliding might play in natural settings. Microarray experiments plus subsequent genetic characterization showed that the machineries of sliding and biofilm formation share the same main components (i.e., surfactin, the hydrophobin BslA, exopolysaccharide, and de novo-formed fatty acids). Sliding proficiency was transduced by the Spo0A-phosphorelay histidine kinases KinB and KinC. We discovered that potassium, a previously known inhibitor of KinC-dependent biofilm formation, is the specific sliding-activating signal through a thus-far-unnoticed cytosolic domain of KinB, which resembles the selectivity filter sequence of potassium channels. The differential expression of the Spo0A~Pi reporter abrB gene and the different levels of the constitutively active form of Spo0A, Sad67, in Δspo0A cells grown in optimized media that simultaneously stimulate motile and sessile behaviors uncover the spatiotemporal response of KinB and KinC to potassium and the gradual increase in Spo0A~Pi that orchestrates the sequential activation of sliding, followed by sessile biofilm formation and finally sporulation in the same population. Overall, these results provide insights into how multicellular behaviors formerly believed to be antagonistic are coordinately activated in benefit of the bacterium and its interaction with the host. PMID:26152584

Flagellar oscillation: a commentary on proposed mechanisms.

PubMed

Woolley, David M

2010-08-01

Eukaryotic flagella and cilia have a remarkably uniform internal 'engine' known as the '9+2' axoneme. With few exceptions, the function of cilia and flagella is to beat rhythmically and set up relative motion between themselves and the liquid that surrounds them. The molecular basis of axonemal movement is understood in considerable detail, with the exception of the mechanism that provides its rhythmical or oscillatory quality. Some kind of repetitive 'switching' event is assumed to occur; there are several proposals regarding the nature of the 'switch' and how it might operate. Herein I first summarise all the factors known to influence the rate of the oscillation (the beating frequency). Many of these factors exert their effect through modulating the mean sliding velocity between the nine doublet microtubules of the axoneme, this velocity being the determinant of bend growth rate and bend propagation rate. Then I explain six proposed mechanisms for flagellar oscillation and review the evidence on which they are based. Finally, I attempt to derive an economical synthesis, drawing for preference on experimental research that has been minimally disruptive of the intricate structure of the axoneme. The 'provisional synthesis' is that flagellar oscillation emerges from an effect of passive sliding direction on the dynein arms. Sliding in one direction facilitates force-generating cycles and dynein-to-dynein synchronisation along a doublet; sliding in the other direction is inhibitory. The direction of the initial passive sliding normally oscillates because it is controlled hydrodynamically through the alternating direction of the propulsive thrust. However, in the absence of such regulation, there can be a perpetual, mechanical self-triggering through a reversal of sliding direction due to the recoil of elastic structures that deform as a response to the prior active sliding. This provisional synthesis may be a useful basis for further examination of the problem.

7 CFR 500.24 - Fee Schedule.

Code of Federal Regulations, 2011 CFR

2011-01-01

... natural or cultural resources or administrative facilities; or take place where members of the public are.... Cinematography: Set Preparation $30$250 plus Supervision Application FeePer Whole Day. Set up; no filming. Filming $1,500 to $3,900 Per Whole Day Sliding scale based on number of people in cast and crew and number...

7 CFR 500.24 - Fee Schedule.

Code of Federal Regulations, 2013 CFR

2013-01-01

... natural or cultural resources or administrative facilities; or take place where members of the public are.... Cinematography: Set Preparation $30 $250 plus Supervision Application FeePer Whole Day. Set up; no filming. Filming $1,500 to $3,900 Per Whole Day Sliding scale based on number of people in cast and crew and number...

7 CFR 500.24 - Fee Schedule.

Code of Federal Regulations, 2014 CFR

2014-01-01

... natural or cultural resources or administrative facilities; or take place where members of the public are.... Cinematography: Set Preparation $30$250 plus Supervision Application FeePer Whole Day. Set up; no filming. Filming $1,500 to $3,900 Per Whole Day Sliding scale based on number of people in cast and crew and number...

7 CFR 500.24 - Fee Schedule.

Code of Federal Regulations, 2012 CFR

2012-01-01

... natural or cultural resources or administrative facilities; or take place where members of the public are.... Cinematography: Set Preparation $30$250 plus Supervision Application FeePer Whole Day. Set up; no filming. Filming $1,500 to $3,900 Per Whole Day Sliding scale based on number of people in cast and crew and number...

Gender differences in emotional responses: a psychophysiological study.

PubMed

Bianchin, Marta; Angrilli, Alessandro

2012-02-28

Gender differences in emotional responses have been investigated in two groups of students, 22 males and 21 females. Participants watched a set of sixty emotional standardized slides divided into pleasant, neutral and unpleasant, while Startle reflex, Evoked Potentials, Heart Rate, facial EMG and Skin Conductance were recorded. Startle reflex amplitude, an index modulated by amygdala and orbitofrontal cortex and sensitive to aversive emotional stimuli, was overall larger in women. In addition, startle emotion modulation was greater in women with respect to men. Slow Evoked Potentials (400-800 ms), a measure representing the cognitive component of the emotional response, revealed gender differences in the left prefrontal site, with women showing greater positivity to unpleasant compared with pleasant slides while men had greater positivity to pleasant vs. neutral slides. Women, compared with men, perceived all slides as less pleasant and reported greater arousal to unpleasant condition. Results are in line with known functional brain differences, at level of limbic and paralimbic structures, between men and women, and point to biologically grounded greater sensitivity and vulnerability of women to adverse/stressful events. Copyright © 2011 Elsevier Inc. All rights reserved.

Sliding Mode Fault Tolerant Control with Adaptive Diagnosis for Aircraft Engines

NASA Astrophysics Data System (ADS)

Xiao, Lingfei; Du, Yanbin; Hu, Jixiang; Jiang, Bin

2018-03-01

In this paper, a novel sliding mode fault tolerant control method is presented for aircraft engine systems with uncertainties and disturbances on the basis of adaptive diagnostic observer. By taking both sensors faults and actuators faults into account, the general model of aircraft engine control systems which is subjected to uncertainties and disturbances, is considered. Then, the corresponding augmented dynamic model is established in order to facilitate the fault diagnosis and fault tolerant controller design. Next, a suitable detection observer is designed to detect the faults effectively. Through creating an adaptive diagnostic observer and based on sliding mode strategy, the sliding mode fault tolerant controller is constructed. Robust stabilization is discussed and the closed-loop system can be stabilized robustly. It is also proven that the adaptive diagnostic observer output errors and the estimations of faults converge to a set exponentially, and the converge rate greater than some value which can be adjusted by choosing designable parameters properly. The simulation on a twin-shaft aircraft engine verifies the applicability of the proposed fault tolerant control method.

Permeability Evolution With Shearing of Simulated Faults in Unconventional Shale Reservoirs

NASA Astrophysics Data System (ADS)

Wu, W.; Gensterblum, Y.; Reece, J. S.; Zoback, M. D.

2016-12-01

Horizontal drilling and multi-stage hydraulic fracturing can lead to fault reactivation, a process thought to influence production from extremely low-permeability unconventional reservoir. A fundamental understanding of permeability changes with shear could be helpful for optimizing reservoir stimulation strategies. We examined the effects of confining pressure and frictional sliding on fault permeability in Eagle Ford shale samples. We performed shear-flow experiments in a triaxial apparatus on four shale samples: (1) clay-rich sample with sawcut fault, (2) calcite-rich sample with sawcut fault, (3) clay-rich sample with natural fault, and (4) calcite-rich sample with natural fault. We used pressure pulse-decay and steady-state flow techniques to measure fault permeability. Initial pore and confining pressures are set to 2.5 MPa and 5.0 MPa, respectively. To investigate the influence of confining pressure on fault permeability, we incrementally raised and lowered the confining pressure and measure permeability at different effective stresses. To examine the effect of frictional sliding on fault permeability, we slide the samples four times at a constant shear displacement rate of 0.043 mm/min for 10 minutes each and measure fault permeability before and after frictional sliding. We used a 3D Laser Scanner to image fault surface topography before and after the experiment. Our results show that frictional sliding can enhance fault permeability at low confining pressures (e.g., ≥5.0 MPa) and reduce fault permeability at high confining pressures (e.g., ≥7.5 MPa). The permeability of sawcut faults almost fully recovers when confining pressure returns to the initial value, and increases with sliding due to asperity damage and subsequent dilation at low confining pressures. In contrast, the permeability of natural faults does not fully recover. It initially increases with sliding, but then decreases with further sliding most likely due to fault gouge blocking fluid pathways.

Accuracy of reading liquid based cytology slides using the ThinPrep Imager compared with conventional cytology: prospective study

PubMed Central

d'Assuncao, Jefferson; Irwig, Les; Macaskill, Petra; Chan, Siew F; Richards, Adele; Farnsworth, Annabelle

2007-01-01

Objective To compare the accuracy of liquid based cytology using the computerised ThinPrep Imager with that of manually read conventional cytology. Design Prospective study. Setting Pathology laboratory in Sydney, Australia. Participants 55 164 split sample pairs (liquid based sample collected after conventional sample from one collection) from consecutive samples of women choosing both types of cytology and whose specimens were examined between August 2004 and June 2005. Main outcome measures Primary outcome was accuracy of slides for detecting squamous lesions. Secondary outcomes were rate of unsatisfactory slides, distribution of squamous cytological classifications, and accuracy of detecting glandular lesions. Results Fewer unsatisfactory slides were found for imager read cytology than for conventional cytology (1.8% v 3.1%; P<0.001). More slides were classified as abnormal by imager read cytology (7.4% v 6.0% overall and 2.8% v 2.2% for cervical intraepithelial neoplasia of grade 1 or higher). Among 550 patients in whom imager read cytology was cervical intraepithelial neoplasia grade 1 or higher and conventional cytology was less severe than grade 1, 133 of 380 biopsy samples taken were high grade histology. Among 294 patients in whom imager read cytology was less severe than cervical intraepithelial neoplasia grade 1 and conventional cytology was grade 1 or higher, 62 of 210 biopsy samples taken were high grade histology. Imager read cytology therefore detected 71 more cases of high grade histology than did conventional cytology, resulting from 170 more biopsies. Similar results were found when one pathologist reread the slides, masked to cytology results. Conclusion The ThinPrep Imager detects 1.29 more cases of histological high grade squamous disease per 1000 women screened than conventional cytology, with cervical intraepithelial neoplasia grade 1 as the threshold for referral to colposcopy. More imager read slides than conventional slides were satisfactory for examination and more contained low grade cytological abnormalities. PMID:17604301

Analysis of Fixed Duty Cycle Hysteretic Flyback Converter for Firing Set Applications.

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

Love, Thomas Michael

2017-05-01

This paper analyzes several performance aspects of the fixed-duty-cycle, hysteretic flyback converter topology typically used in firing sets. Topologies with and without active pulse-by-pulse current limiting are considered, and closed-form expressions in terms of basic operating parameters are derived.

The Ammonia-Soda Process.

ERIC Educational Resources Information Center

Tingle, M.

1979-01-01

This article is a condensed version of a commentary written to accompany a set of slides which describes the ammonia-soda process used by the ammonia-soda plant at Northwich of the United Kingdom. (HM)

Marine ice sheet model performance depends on basal sliding physics and sub-shelf melting

NASA Astrophysics Data System (ADS)

Gladstone, Rupert Michael; Warner, Roland Charles; Galton-Fenzi, Benjamin Keith; Gagliardini, Olivier; Zwinger, Thomas; Greve, Ralf

2017-01-01

Computer models are necessary for understanding and predicting marine ice sheet behaviour. However, there is uncertainty over implementation of physical processes at the ice base, both for grounded and floating glacial ice. Here we implement several sliding relations in a marine ice sheet flow-line model accounting for all stress components and demonstrate that model resolution requirements are strongly dependent on both the choice of basal sliding relation and the spatial distribution of ice shelf basal melting.Sliding relations that reduce the magnitude of the step change in basal drag from grounded ice to floating ice (where basal drag is set to zero) show reduced dependence on resolution compared to a commonly used relation, in which basal drag is purely a power law function of basal ice velocity. Sliding relations in which basal drag goes smoothly to zero as the grounding line is approached from inland (due to a physically motivated incorporation of effective pressure at the bed) provide further reduction in resolution dependence.A similar issue is found with the imposition of basal melt under the floating part of the ice shelf: melt parameterisations that reduce the abruptness of change in basal melting from grounded ice (where basal melt is set to zero) to floating ice provide improved convergence with resolution compared to parameterisations in which high melt occurs adjacent to the grounding line.Thus physical processes, such as sub-glacial outflow (which could cause high melt near the grounding line), impact on capability to simulate marine ice sheets. If there exists an abrupt change across the grounding line in either basal drag or basal melting, then high resolution will be required to solve the problem. However, the plausible combination of a physical dependency of basal drag on effective pressure, and the possibility of low ice shelf basal melt rates next to the grounding line, may mean that some marine ice sheet systems can be reliably simulated at a coarser resolution than currently thought necessary.

Failure mechanism of coated biomaterials under high impact-sliding contact stresses

NASA Astrophysics Data System (ADS)

Chen, Ying

This study uses a newly developed testing method--- inclined cyclic impact-sliding test to investigate the failure behaviors of different types of biomaterials, (SS316L, Ti6Al4V and CoCr) coated by different coatings (TiN, DLC and PEO), under extremely high dynamic contact stress conditions. This test method can simulate the combined impact and sliding/rolling loading conditions, which is very practical in many aspects of commercial usages. During the tests, fatigue cracking, chipping, peeling and material transferring were observed in damaged area. This research is mainly focused on the failure behaviors of load-bearing materials which cyclic impacting and sliding are always involved. This purpose was accomplished in the three stages: First, impact-sliding test was carried out on TiN coated unhardened M2. It was found that soft substrate can cause early failure of coating due to the considerable plastic deformation in the substrate. In this case, stronger substrate is required to support coating better when tested under high contact stresses. Second, PEO coated Ti-6Al-4V was tested under pure sliding and impact-sliding wear conditions. PEO coating was found not strong enough to afford the high contact pressure under cyclic impact-sliding wear test due to its porous surface structure. However, the wear performance of PEO coating was enhanced due to the sub-stoichiometric oxide. To sum up, for load-bearing biomedical implants involved in high impacting movement, PEO coating may not be a promising surface protection. Third, the dense, smooth PVD/CVD bio-inert coatings were reconsidered. DLC and TiN coatings, combined by different substrates together with different interface materials were tested under the cyclic impact-sliding test using a set of proper loading. The results show that to choose a proper combination of coating, interface and substrate based on their mechanical properties is of great importance under the test condition. Hard substrates provide support to coating better and a ductile and adhesive interface layer can delay the cracked coating from peeled-off.

Deep Learning for Classification of Colorectal Polyps on Whole-slide Images

PubMed Central

Korbar, Bruno; Olofson, Andrea M.; Miraflor, Allen P.; Nicka, Catherine M.; Suriawinata, Matthew A.; Torresani, Lorenzo; Suriawinata, Arief A.; Hassanpour, Saeed

2017-01-01

Context: Histopathological characterization of colorectal polyps is critical for determining the risk of colorectal cancer and future rates of surveillance for patients. However, this characterization is a challenging task and suffers from significant inter- and intra-observer variability. Aims: We built an automatic image analysis method that can accurately classify different types of colorectal polyps on whole-slide images to help pathologists with this characterization and diagnosis. Setting and Design: Our method is based on deep-learning techniques, which rely on numerous levels of abstraction for data representation and have shown state-of-the-art results for various image analysis tasks. Subjects and Methods: Our method covers five common types of polyps (i.e., hyperplastic, sessile serrated, traditional serrated, tubular, and tubulovillous/villous) that are included in the US Multisociety Task Force guidelines for colorectal cancer risk assessment and surveillance. We developed multiple deep-learning approaches by leveraging a dataset of 2074 crop images, which were annotated by multiple domain expert pathologists as reference standards. Statistical Analysis: We evaluated our method on an independent test set of 239 whole-slide images and measured standard machine-learning evaluation metrics of accuracy, precision, recall, and F1 score and their 95% confidence intervals. Results: Our evaluation shows that our method with residual network architecture achieves the best performance for classification of colorectal polyps on whole-slide images (overall accuracy: 93.0%, 95% confidence interval: 89.0%–95.9%). Conclusions: Our method can reduce the cognitive burden on pathologists and improve their efficacy in histopathological characterization of colorectal polyps and in subsequent risk assessment and follow-up recommendations. PMID:28828201

Tuberculin Skin Testing

MedlinePlus

... Aggregate Reports Slide Sets Epidemiology of Tuberculosis Among Non-U.S.​–Born Persons in the United States, 1993– ... immunosuppressed for other reasons (e.g., taking the equivalent of >15 mg/day of prednisone for 1 ...

Hierarchical opal grating films prepared by slide coating of colloidal dispersions in binary liquid media.

PubMed

Lee, Wonmok; Kim, Seulgi; Kim, Seulki; Kim, Jin-Ho; Lee, Hyunjung

2015-02-15

There are active researches on well ordered opal films due to their possible applications to various photonic devices. A recently developed slide coating method is capable of rapid fabrication of large area opal films from aqueous colloidal dispersion. In the current study, the slide coating of polystyrene colloidal dispersions in water/i-propanol (IPA) binary media is investigated. Under high IPA content in a dispersing medium, resulting opal film showed a deterioration of long range order, as well as a decreased film thickness due to dilution effect. From the binary liquid, the dried opal films exhibited the unprecedented topological groove patterns with varying periodic distances as a function of alcohol contents in the media. The groove patterns were consisted of the hierarchical structures of the terraced opal layers with periodic thickness variations. The origin of the groove patterns was attributed to a shear-induced periodic instability of colloidal concentration within a thin channel during the coating process which was directly converted to a groove patterns in a resulting opal film due to rapid evaporation of liquid. The groove periods of opal films were in the range of 50-500 μm, and the thickness differences between peak and valley of the groove were significantly large enough to be optically distinguishable, such that the coated films can be utilized as the optical grating film to disperse infra-red light. Utilizing a lowered hydrophilicity of water/IPA dispersant, an opal film could be successfully coated on a flexible Mylar film without significant dewetting problem. Copyright © 2014 Elsevier Inc. All rights reserved.

A novel fluorescence sensor based on covalent immobilization of 3-amino-9-ethylcarbazole by using silver nanoparticles as bridges and carriers.

PubMed

Tan, Shu-Zhen; Hu, Yan-Jun; Gong, Fu-Chun; Cao, Zhong; Xia, Jiao-Yun; Zhang, Ling

2009-03-23

A novel technique of covalent immobilization of indicator dyes in the preparation of fluorescence sensors is developed. Silver nanoparticles are used as bridges and carriers for anchoring indicator dyes. 3-amino-9-ethylcarbazole (AEC) was employed as an example of indicator dyes with terminal amino groups and covalently immobilized onto the outmost surface of a quartz glass slide. First, the glass slide was functionalized by (3-mercaptopropyl) trimethoxysilane (MPS) to form a thiol-terminated self-assembled monolayer, where silver nanoparticles were strongly bound to the surface through covalent bonding. Then, 16-mercaptohexadecanoic acid (MHDA) was self-assembled to bring carboxylic groups onto the surface of silver nanoparticles. A further activation by using 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) converted the carboxylic groups into succinimide esters. Finally, the active succinimide esters on the surface of silver nanoparticles were reacted with AEC. Thus, AEC was covalently bound to the glass slide and an AEC-immobilized sensor was obtained. The sensor exhibited very satisfactory reproducibility and reversibility, rapid response and no dye-leaching. Rutin can quench the fluorescence intensity of the sensor and be measured by using the sensor. The linear response of the sensor to rutin covers the range from 2.0 x 10(-6) to 1.5 x 10(-4) molL(-1) with a detection limit of 8.0 x 10(-7) molL(-1). The proposed technique may be feasible to the covalent immobilization of other dyes with primary amino groups.

Phase and speed synchronization control of four eccentric rotors driven by induction motors in a linear vibratory feeder with unknown time-varying load torques using adaptive sliding mode control algorithm

NASA Astrophysics Data System (ADS)

Kong, Xiangxi; Zhang, Xueliang; Chen, Xiaozhe; Wen, Bangchun; Wang, Bo

2016-05-01

In this paper, phase and speed synchronization control of four eccentric rotors (ERs) driven by induction motors in a linear vibratory feeder with unknown time-varying load torques is studied. Firstly, the electromechanical coupling model of the linear vibratory feeder is established by associating induction motor's model with the dynamic model of the system, which is a typical under actuated model. According to the characteristics of the linear vibratory feeder, the complex control problem of the under actuated electromechanical coupling model converts to phase and speed synchronization control of four ERs. In order to keep the four ERs operating synchronously with zero phase differences, phase and speed synchronization controllers are designed by employing adaptive sliding mode control (ASMC) algorithm via a modified master-slave structure. The stability of the controllers is proved by Lyapunov stability theorem. The proposed controllers are verified by simulation via Matlab/Simulink program and compared with the conventional sliding mode control (SMC) algorithm. The results show the proposed controllers can reject the time-varying load torques effectively and four ERs can operate synchronously with zero phase differences. Moreover, the control performance is better than the conventional SMC algorithm and the chattering phenomenon is attenuated. Furthermore, the effects of reference speed and parametric perturbations are discussed to show the strong robustness of the proposed controllers. Finally, experiments on a simple vibratory test bench are operated by using the proposed controllers and without control, respectively, to validate the effectiveness of the proposed controllers further.

Compact 3D printed module for fluorescence and label-free imaging using evanescent excitation

NASA Astrophysics Data System (ADS)

Pandey, Vikas; Gupta, Shalini; Elangovan, Ravikrishnan

2018-01-01

Total internal reflection fluorescence (TIRF) microscopy is widely used for selective excitation and high-resolution imaging of fluorophores, and more recently label-free nanosized objects, with high vertical confinement near a liquid-solid interface. Traditionally, high numerical aperture objectives (>1.4) are used to simultaneously generate evanescent waves and collect fluorescence emission signals which limits their use to small area imaging (<0.1 mm2). Objective-based TIRFs are also expensive as they require dichroic mirrors and efficient notch filters to prevent specular reflection within the objective lenses. We have developed a compact 3D module called cTIRF that can generate evanescent waves in microscope glass slides via a planar waveguide illumination. The module can be attached as a fixture to any existing optical microscope, converting it into a TIRF and enabling high signal-to-noise ratio (SNR) fluorescence imaging using any magnification objective. As the incidence optics is perpendicular to the detector, label-free evanescent scattering-based imaging of submicron objects can also be performed without using emission filters. SNR is significantly enhanced in this case as compared to cTIRF alone, as seen through our model experiments performed on latex beads and mammalian cells. Extreme flexibility and the low cost of our approach makes it scalable for limited resource settings.

9 CFR 130.50 - Payment of user fees.

Code of Federal Regulations, 2011 CFR

2011-01-01

..., such as tests on samples submitted to NVSL or FADDL, diagnostic reagents, slide sets, tissue sets, and..., MD 20738-1231. (2) All types of checks, including traveler's checks, drawn on a U.S. bank in U.S.... bank in U.S. dollars and made payable to the U.S. Department of Agriculture or USDA; or (4) Credit...

9 CFR 130.50 - Payment of user fees.

Code of Federal Regulations, 2013 CFR

2013-01-01

..., such as tests on samples submitted to NVSL or FADDL, diagnostic reagents, slide sets, tissue sets, and..., MD 20738-1231. (2) All types of checks, including traveler's checks, drawn on a U.S. bank in U.S.... bank in U.S. dollars and made payable to the U.S. Department of Agriculture or USDA; or (4) Credit...

9 CFR 130.50 - Payment of user fees.

Code of Federal Regulations, 2010 CFR

2010-01-01

..., such as tests on samples submitted to NVSL or FADDL, diagnostic reagents, slide sets, tissue sets, and..., MD 20738-1231. (2) All types of checks, including traveler's checks, drawn on a U.S. bank in U.S.... bank in U.S. dollars and made payable to the U.S. Department of Agriculture or USDA; or (4) Credit...

9 CFR 130.50 - Payment of user fees.

Code of Federal Regulations, 2012 CFR

2012-01-01

..., such as tests on samples submitted to NVSL or FADDL, diagnostic reagents, slide sets, tissue sets, and..., MD 20738-1231. (2) All types of checks, including traveler's checks, drawn on a U.S. bank in U.S.... bank in U.S. dollars and made payable to the U.S. Department of Agriculture or USDA; or (4) Credit...

9 CFR 130.50 - Payment of user fees.

Code of Federal Regulations, 2014 CFR

2014-01-01

..., such as tests on samples submitted to NVSL or FADDL, diagnostic reagents, slide sets, tissue sets, and..., MD 20738-1231. (2) All types of checks, including traveler's checks, drawn on a U.S. bank in U.S.... bank in U.S. dollars and made payable to the U.S. Department of Agriculture or USDA; or (4) Credit...

The Use of the Ambulatory Setting for Patient Self-Education.

ERIC Educational Resources Information Center

Newkirk, Gary; And Others

1979-01-01

A self-instructional health education program that utilizes a slide-tape device was studied to determine whether it could be educationally effective in an ambulatory clinical setting without being an inconvenience to patients. Infant and child nutrition was chosen as the topic to be used in the waiting room of a pediatric clinic. (JMD)

Educators Guide to Free Filmstrips. Twenty-Third Edition.

ERIC Educational Resources Information Center

Horkheimer, Mary Foley, Comp.; Diffor, John C., Comp.

A total of 453 titles of filmstrips, slide sets, and sets of transparencies available free of charge to educators are listed in this guide. More than 20,000 separate frames are offered from 95 sources. Twenty of the filmstrips may be retained permanently by the borrower. The films cover topics in the fields of accident prevention, aerospace…

Digital Pathology Evaluation in the Multicenter Nephrotic Syndrome Study Network (NEPTUNE)

PubMed Central

Nast, Cynthia C.; Jennette, J. Charles; Hodgin, Jeffrey B.; Herzenberg, Andrew M.; Lemley, Kevin V.; Conway, Catherine M.; Kopp, Jeffrey B.; Kretzler, Matthias; Lienczewski, Christa; Avila-Casado, Carmen; Bagnasco, Serena; Sethi, Sanjeev; Tomaszewski, John; Gasim, Adil H.

2013-01-01

Summary Pathology consensus review for clinical trials and disease classification has historically been performed by manual light microscopy with sequential section review by study pathologists, or multi-headed microscope review. Limitations of this approach include high intra- and inter-reader variability, costs, and delays for slide mailing and consensus reviews. To improve this, the Nephrotic Syndrome Study Network (NEPTUNE) is systematically applying digital pathology review in a multicenter study using renal biopsy whole slide imaging (WSI) for observation-based data collection. Study pathology materials are acquired, scanned, uploaded, and stored in a web-based information system that is accessed through a web-browser interface. Quality control includes metadata and image quality review. Initially, digital slides are annotated, with each glomerulus identified, given a unique number, and maintained in all levels until the glomerulus disappears or sections end. The software allows viewing and annotation of multiple slide sections concurrently. Analysis utilizes “descriptors” for patterns of injury, rather than diagnoses, in renal parenchymal compartments. This multidimensional representation via WSI, allows more accurate glomerular counting and identification of all lesions in each glomerulus, with data available in a searchable database. The use of WSI brings about efficiency critical to pathology review in a clinical trial setting, including independent review by multiple pathologists, improved intraobserver and interobserver reproducibility, efficiencies and risk reduction in slide circulation and mailing, centralized management of data integrity and slide images for current or future studies, and web-based consensus meetings. The overall effect is improved incorporation of pathology review in a budget neutral approach. PMID:23393107

Optical redox imaging of fixed unstained tissue slides to identify biomarkers for breast cancer diagnosis/prognosis: feasibility study

NASA Astrophysics Data System (ADS)

Xu, He N.; Tchou, Julia; Li, Yusheng; Feng, Min; Zhang, Paul; Quinn, William J.; Baur, Joseph A.; Li, Lin Z.

2018-02-01

We previously showed that optical redox imaging (ORI) of snap-frozen breast biopsies by the Chance redox scanner readily discriminates cancer from normal tissue. Moreover, indices of redox heterogeneity differentiate among tumor xenografts with different metastatic potential. These observations suggest that ORI of fluorescence of NADH and oxidized flavoproteins (Fp) may provide diagnostic/prognostic value for clinical applications. In this work, we investigate whether ORI of formalin-fixed-paraffin-embedded (FFPE) unstained clinical tissue slides of breast tumors is feasible and comparable to ORI of snap-frozen tumors. If ORI of FFPE is validated, it will enhance the versatility of ORI as a novel diagnostic/prognostic assay as FFPE samples are readily available. ORI of fixed tissue slides was performed using a fluorescence microscope equipped with a precision automated stage and appropriate optical filters. We developed a vignette correction algorithm to remove the tiling effect of stitched-images. The preliminary data from imaging fixed slides of breast tumor xenografts showed intratumor redox heterogeneity patterns similar to that of the frozen tissues imaged by the Chance redox scanner. From ORI of human breast tissue slides we identified certain redox differences among normal, ductal carcinoma in situ, and invasive carcinoma. We found paraformaldehyde fixation causes no change in NADH signals but enhances Fp signals of fresh muscle fibers. We also investigated the stability of the fluorescence microscope and reproducibility of tissue slide fluorescence signals. We plan to validate the diagnostic/prognostic value of ORI using clinically annotated breast cancer sample set from patients with long-term follow-up data.

Assessing the chronology of bedrock landslides in the Oregon Coastal Range using visible near-infrared spectroscopy

NASA Astrophysics Data System (ADS)

Mathabane, N.; Cerovski-Darriau, C.; Sweeney, K. E.; Roering, J. J.

2013-12-01

Obtaining accurate chronological data for landslides is critical to understanding their causes as well as their dynamics. The ability to easily and inexpensively date various parts of a landslide can provide insight not only into the 'When' of landslides but also on the 'How' and 'Why' as well. In this study, we apply visible near-infrared (VisNIR) spectroscopy as a means to date landslide soils in a setting with uniform climate and bedrock lithology. In our Oregon Coast Range site, as sandstone-derived soils weather over time, pedogenic hematite accumulates and alters the color of the soil at a quantifiable and discernable rate. This rate having already been established through a soil chronosequence study, we can use the redness of a soil as a proxy for soil age. This is a potentially economical dating method as it does not rely on expensive radioisotopes and requires only a small amount of sample to process. We collected 39 B-horizon soil samples from 7 different slides and used VisNIR spectroscopy to identify the soil residence time of the landslides. The majority of the samples possessed ages between 75,000 and 150,000 years of age, though several slides registered ages over 200,000 years. The average percent error associated with the landslide ages was ~30-35%, although this value was lower for younger slides (<100,000 years) and greater for slides (>200,000 years). Younger slides were more homogenous in age while older slides exhibited more variability. Additionally, there was lower variability in auger-collected samples when compared to samples collected from road-cuts. Our results suggest that VisNIR spectroscopy may prove a more useful dating method on younger, less disturbed landslides but fail to truly capture the age of older, more complicated slides due to its reliance on a specific pedogentic model for hematite weathering as well as the increased risk for complex slide history. This method could be useful in a regional characterization of landslide chronology for similar biomes and provide scientists with a currently lacking catalogue of ancient landslide ages. Such a catalogue could provide significant insight into the mechanisms and potential triggers of bedrock landslides. Landslide ages and geospatial distribution of the four largest slides sampled in the course of this study. There was significant local variability in slide ages, especially in older, redder slides like Vaughn and Wolf Creek.

BCG (Bacille Calmette-Guerin) Vaccine

MedlinePlus

... Aggregate Reports Slide Sets Epidemiology of Tuberculosis Among Non-U.S.​–Born Persons in the United States, 1993– ... immunosuppressed for other reasons (e.g., taking the equivalent of >15 mg/day of prednisone for 1 ...

Earthquakes in Alaska

USGS Publications Warehouse

Haeussler, Peter J.; Plafker, George

1995-01-01

Earthquake risk is high in much of the southern half of Alaska, but it is not the same everywhere. This map shows the overall geologic setting in Alaska that produces earthquakes. The Pacific plate (darker blue) is sliding northwestward past southeastern Alaska and then dives beneath the North American plate (light blue, green, and brown) in southern Alaska, the Alaska Peninsula, and the Aleutian Islands. Most earthquakes are produced where these two plates come into contact and slide past each other. Major earthquakes also occur throughout much of interior Alaska as a result of collision of a piece of crust with the southern margin.

Lunar Missions and Datasets

NASA Technical Reports Server (NTRS)

Cohen, Barbara A.

2009-01-01

There are two slide presentations contained in this document. The first reviews the lunar missions from Surveyor, Galileo, Clementine, the Lunar Prospector, to upcoming lunar missions, Lunar Reconnaissance Orbiter (LRO), Lunar Crater Observation & Sensing Satellite (LCROSS), Acceleration, Reconnection, Turbulence and Electrodynamics of Moon's Interaction with the Sun (ARTEMIS), Gravity Recovery and Interior Laboratory (GRAIL), Lunar Atmosphere, Dust and Environment Explorer (LADEE), ILN and a possible Robotic sample return mission. The information that the missions about the moon is reviewed. The second set of slides reviews the lunar meteorites, and the importance of lunar meteorites to adding to our understanding of the moon.

Riding the storm--landslide danger in the San Francisco Bay Area

USGS Publications Warehouse

Adams, Karen

2007-01-01

Movie Synopsis: --A catastrophic 1982 rainstorm triggered 18,000 landslides in the Bay Area, claiming 25 lives and causing $66 million in property damage. --The combination of steep slopes, weak rocks, and intense winter storms make Bay Area uplands an ideal setting for landslides. --Landslides include both swift, potentially deadly debris flows and slower, but destructive deepseated slides. --Learn what USGS scientists have discovered about landslide dynamics and which slopes are most susceptible to sliding. --Hear the devastating stories of Bay Area residents affected by landslides and learn to recognize the danger signs.

Mining disease state converters for medical intervention of diseases.

PubMed

Dong, Guozhu; Duan, Lei; Tang, Changjie

2010-02-01

In applications such as gene therapy and drug design, a key goal is to convert the disease state of diseased objects from an undesirable state into a desirable one. Such conversions may be achieved by changing the values of some attributes of the objects. For example, in gene therapy one may convert cancerous cells to normal ones by changing some genes' expression level from low to high or from high to low. In this paper, we define the disease state conversion problem as the discovery of disease state converters; a disease state converter is a small set of attribute value changes that may change an object's disease state from undesirable into desirable. We consider two variants of this problem: personalized disease state converter mining mines disease state converters for a given individual patient with a given disease, and universal disease state converter mining mines disease state converters for all samples with a given disease. We propose a DSCMiner algorithm to discover small and highly effective disease state converters. Since real-life medical experiments on living diseased instances are expensive and time consuming, we use classifiers trained from the datasets of given diseases to evaluate the quality of discovered converter sets. The effectiveness of a disease state converter is measured by the percentage of objects that are successfully converted from undesirable state into desirable state as deemed by state-of-the-art classifiers. We use experiments to evaluate the effectiveness of our algorithm and to show its effectiveness. We also discuss possible research directions for extensions and improvements. We note that the disease state conversion problem also has applications in customer retention, criminal rehabilitation, and company turn-around, where the goal is to convert class membership of objects whose class is an undesirable class.

Analysis and Design of High-Order Parallel Resonant Converters

NASA Astrophysics Data System (ADS)

Batarseh, Issa Eid

1990-01-01

In this thesis, a special state variable transformation technique has been derived for the analysis of high order dc-to-dc resonant converters. Converters comprised of high order resonant tanks have the advantage of utilizing the parasitic elements by making them part of the resonant tank. A new set of state variables is defined in order to make use of two-dimensional state-plane diagrams in the analysis of high order converters. Such a method has been successfully used for the analysis of the conventional Parallel Resonant Converters (PRC). Consequently, two -dimensional state-plane diagrams are used to analyze the steady state response for third and fourth order PRC's when these converters are operated in the continuous conduction mode. Based on this analysis, a set of control characteristic curves for the LCC-, LLC- and LLCC-type PRC are presented from which various converter design parameters are obtained. Various design curves for component value selections and device ratings are given. This analysis of high order resonant converters shows that the addition of the reactive components to the resonant tank results in converters with better performance characteristics when compared with the conventional second order PRC. Complete design procedure along with design examples for 2nd, 3rd and 4th order converters are presented. Practical power supply units, normally used for computer applications, were built and tested by using the LCC-, LLC- and LLCC-type commutation schemes. In addition, computer simulation results are presented for these converters in order to verify the theoretical results.

Potential effects of gas hydrate on human welfare

PubMed Central

Kvenvolden, Keith A.

1999-01-01

For almost 30 years. serious interest has been directed toward natural gas hydrate, a crystalline solid composed of water and methane, as a potential (i) energy resource, (ii) factor in global climate change, and (iii) submarine geohazard. Although each of these issues can affect human welfare, only (iii) is considered to be of immediate importance. Assessments of gas hydrate as an energy resource have often been overly optimistic, based in part on its very high methane content and on its worldwide occurrence in continental margins. Although these attributes are attractive, geologic settings, reservoir properties, and phase-equilibria considerations diminish the energy resource potential of natural gas hydrate. The possible role of gas hydrate in global climate change has been often overstated. Although methane is a “greenhouse” gas in the atmosphere, much methane from dissociated gas hydrate may never reach the atmosphere, but rather may be converted to carbon dioxide and sequestered by the hydrosphere/biosphere before reaching the atmosphere. Thus, methane from gas hydrate may have little opportunity to affect global climate change. However, submarine geohazards (such as sediment instabilities and slope failures on local and regional scales, leading to debris flows, slumps, slides, and possible tsunamis) caused by gas-hydrate dissociation are of immediate and increasing importance as humankind moves to exploit seabed resources in ever-deepening waters of coastal oceans. The vulnerability of gas hydrate to temperature and sea level changes enhances the instability of deep-water oceanic sediments, and thus human activities and installations in this setting can be affected. PMID:10097052

Magnetic Analysis of Post-mortem Hippocampal Tissue from Alzheimer's Patients: Changes with Progression of the Disease.

NASA Astrophysics Data System (ADS)

Fuller, M.; Zinin, P.; Favia, J.; Tatsumi, L.; Kletetschka, G.; Adachi, T.

2007-12-01

Increases of iron in the human brain with age have been observed and may be accompanied by the development of neurodegenerative diseases, such as Alzheimer's. We have measured the magnetic characteristics of several sets of slides of hippocampal tissue from deceased Alzheimer patients. The slides were made available by the Harvard Brain Bank. The pathology of the tissue was classified in the Braak stages I to VI used to describe the progression of the disease. In general, the slides from patients with higher Braak stages and development of fibrillary tangles and plaques had greater magnetic moments than did those with Braak stage II. However, the peak values were at stage IV and V. To mitigate errors due to the inevitable differences in masses of the tissue on individual slides and their precise location in the hippocampus, ratios of magnetic properties were also observed. Ratios of Anhysteretic Remanent Magnetizaton (ARM) to Isothermal Remanent Magnetization (IRM) were obtained and showed a decrease from Stage II to the more advanced stages, with the minimum values at stages IV and V. The acquisition and demagnetization of IRM are consistent with the presence of magnetite, but also indicate a magnetically harder phase.

A new fuzzy-disturbance observer-enhanced sliding controller for vibration control of a train-car suspension with magneto-rheological dampers

NASA Astrophysics Data System (ADS)

Nguyen, Sy Dzung; Choi, Seung-Bok; Nguyen, Quoc Hung

2018-05-01

Semi-active train-car suspensions are always impacted negatively by uncertainty and disturbance (UAD). In order to deal with this, we propose a novel optimal fuzzy disturbance observer-enhanced sliding mode controller (FDO-SMC) for magneto-rheological damper (MRD)-based semi-active train-car suspensions subjected to UAD whose variability rate may be high but bounded. The two main parts of the FDO-SMC are an adaptive sliding mode controller (ad-SMC) and an optimal fuzzy disturbance observer (op-FDO). As the first step, the initial structures of the sliding mode controller (SMC) and disturbance observer (DO) are built. Adaptive update laws for the SMC and DO are then set up synchronously via Lyapunov stability analysis. Subsequently, an optimal fuzzy system (op-FS) is designed to fully implement a parameter constraint mechanism so as to guarantee the system stability converging to the desired state even if the UAD variability rate increases in a given range. As a result, both the ad-SMC and op-FDO are formulated. It is shown from the comparative work with existing controllers that the proposed method provides the best vibration control capability with relatively low consumed power.

Bifurcation of elastic solids with sliding interfaces

NASA Astrophysics Data System (ADS)

Bigoni, D.; Bordignon, N.; Piccolroaz, A.; Stupkiewicz, S.

2018-01-01

Lubricated sliding contact between soft solids is an interesting topic in biomechanics and for the design of small-scale engineering devices. As a model of this mechanical set-up, two elastic nonlinear solids are considered jointed through a frictionless and bilateral surface, so that continuity of the normal component of the Cauchy traction holds across the surface, but the tangential component is null. Moreover, the displacement can develop only in a way that the bodies in contact do neither detach, nor overlap. Surprisingly, this finite strain problem has not been correctly formulated until now, so this formulation is the objective of the present paper. The incremental equations are shown to be non-trivial and different from previously (and erroneously) employed conditions. In particular, an exclusion condition for bifurcation is derived to show that previous formulations based on frictionless contact or `spring-type' interfacial conditions are not able to predict bifurcations in tension, while experiments-one of which, ad hoc designed, is reported-show that these bifurcations are a reality and become possible when the correct sliding interface model is used. The presented results introduce a methodology for the determination of bifurcations and instabilities occurring during lubricated sliding between soft bodies in contact.

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

Skidmore, Cary Bradford; Preston, Daniel N.

These are a set of slides for educational outreach to children on high explosives science. It gives an introduction to the elements involved in this science: carbon, hydrogen, nitrogen, and oxygen. Combined, these form the molecule HMX. Many pictures are also included to illustrate explosions.

Implementation of LED fluorescence microscopy for diagnosis of pulmonary and HIV-associated tuberculosis in a hospital setting in Indonesia.

PubMed

Chaidir, Lidya; Parwati, Ida; Annisa, Jessi; Muhsinin, Soni; Meilana, Intan; Alisjahbana, Bachti; van Crevel, Reinout

2013-01-01

Fluorescence microscopy (FM) has not been implemented widely in TB endemic settings and little evaluation has been done in HIV-infected patients. We evaluated diagnostic performance, time and costs of FM with light-emitting diodes technology (LED-FM), compared with conventional (Zieh-Neelsen) microscopy in a hospital in Indonesia which acts as referral centre for HIV-infected patients. We included pulmonary tuberculosis suspects from the outpatient and HIV clinic. Direct and concentrated sputum smears were examined using LED-FM and ZN microscopy by two technicians who were blinded for the HIV-status and the result of the comparative test. Mean reading time per slide was recorded and cost of each slide was calculated. Mycobacteria culture served as the reference standard. Among 404 tuberculosis suspects from the outpatient clinic and 256 from the HIV clinic, mycobacteria culture was positive in 12.6% and 27%, respectively. The optimal sensitivity of LED-FM was achieved by using a threshold of ≥2 AFB/length. LED-FM had a higher sensitivity (75.5% vs. 54.9%, P<0.01) but lower specificity (90.0% vs 96.6%, P<0.01) compared to ZN microscopy. HIV was associated with a lower sensitivity but similar specificity. The average reading time using LED-FM was significantly shorter (2.23±0.78 vs 5.82±1.60 minutes, P<0.01), while costs per slide were similar. High sensitivity of LED-FM combined with shorter reading time of sputum smear slides make this method a potential alternative to ZN microscopy. Additional data on specificity are needed for effective implementation of this technique in high burden TB laboratories.

Enabling digital pathology in the diagnostic setting: navigating through the implementation journey in an academic medical centre.

PubMed

Cheng, Chee Leong; Azhar, Rafay; Sng, Shi Hui Adeline; Chua, Yong Quan; Hwang, Jacqueline Siok Gek; Chin, Jennifer Poi Fun; Seah, Waih Khuen; Loke, Janel Chui Ling; Ang, Roy Hang Leng; Tan, Puay Hoon

2016-09-01

As digital pathology (DP) and whole slide imaging (WSI) technology advance and mature, there is an increasing drive to incorporate DP into the diagnostic environment. However, integration of DP into the diagnostic laboratory is a non-trivial task and filled with unexpected challenges unlike standalone implementations. We share our journey of implementing DP in the diagnostic laboratory setting, highlighting seven key guiding principles that drive the progression through implementation into deployment and beyond. The DP implementation with laboratory information system integration was completed in 8 months, including validation of the solution for diagnostic use in accordance with College of American Pathologists guidelines. We also conducted prospective validation via paired delivery of glass slides and WSI to our pathologists postdeployment. Common themes in our guiding principles included emphasis on workflow and being comprehensive in the approach, looking beyond pathologist user champions and expanding into an extended project team involving laboratory technicians, clerical/data room staff and archival staff. Concordance between glass slides and WSI ranged from 93% to 100% among various applications on validation. We also provided equal opportunities for every pathologist throughout the department to be competent and confident with DP through prospective validation, with overall concordance of 96% compared with glass slides, allowing appreciation of the advantages and limitations of WSI, hence enabling the use of DP as a useful diagnostic modality. Smooth integration of DP into the diagnostic laboratory is possible with careful planning, discipline and a systematic approach adhering to our guiding principles. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Ocean floor mounting of wave energy converters

DOEpatents

Siegel, Stefan G

2015-01-20

A system for mounting a set of wave energy converters in the ocean includes a pole attached to a floor of an ocean and a slider mounted on the pole in a manner that permits the slider to move vertically along the pole and rotate about the pole. The wave energy converters can then be mounted on the slider to allow adjustment of the depth and orientation of the wave energy converters.

Analysis of self-oscillating dc-to-dc converters

NASA Technical Reports Server (NTRS)

Burger, P.

1974-01-01

The basic operational characteristics of dc-to-dc converters are analyzed along with the basic physical characteristics of power converters. A simple class of dc-to-dc power converters are chosen which could satisfy any set of operating requirements, and three different controlling methods in this class are described in detail. Necessary conditions for the stability of these converters are measured through analog computer simulation whose curves are related to other operational characteristics, such as ripple and regulation. Further research is suggested for the solution of absolute stability and efficient physical design of this class of power converters.

Role of gas hydrates in slope failure on frontal ridge of northern Cascadia margin

NASA Astrophysics Data System (ADS)

Yelisetti, Subbarao; Spence, George D.; Riedel, Michael

2014-10-01

Several slope failures are observed near the deformation front on the frontal ridges of the northern Cascadia accretionary margin off Vancouver Island. The cause for these events is not clear, although several lines of evidence indicate a possible connection between the occurrence of gas hydrate and submarine landslide features. The presence of gas hydrate is indicated by a prominent bottom-simulating reflector (BSR), at a depth of ˜265-275 m beneath the seafloor (mbsf), as interpreted from vertical-incidence and wide-angle seismic data beneath the ridge crests of the frontal ridges. For one slide, informally called Slipstream Slide, the velocity structure inferred from tomography analyses shows anomalous high velocities values of about 2.0 km s-1 at shallow depths of 100 mbsf. The estimated depth of the glide plane (100 ± 10 m) closely matches the depth of these shallow high velocities. In contrast, at a frontal ridge slide just to the northwest (informally called Orca Slide), the glide plane occurs at the same depth as the current BSR. Our new results indicate that the glide plane of the Slipstream slope failure is associated with the contrast between sediments strengthened by gas hydrate and overlying sediments where little or no hydrate is present. In contrast, the glide plane of Orca Slide is between sediment strengthened by hydrate underlain by sediments beneath the gas hydrate stability zone, possibly containing free gas. Additionally, a set of margin perpendicular normal faults are imaged from seafloor down to BSR depth at both frontal ridges. As inferred from the multibeam bathymetry, the estimated volume of the material lost during the slope failure at Slipstream Slide is about 0.33 km3, and ˜0.24 km3 of this volume is present as debris material on the ocean basin floor. The 20 per cent difference is likely due to more widely distributed fine sediments not easily detectable as bathymetric anomalies. These volume estimates on the Cascadia margin are approaching the mass failure volume for other slides that have generated large tsunamis-for example 1-3 km3 for a 1998 Papua New Guinea slide.

Combination of statistical and physically based methods to assess shallow slide susceptibility at the basin scale

NASA Astrophysics Data System (ADS)

Oliveira, Sérgio C.; Zêzere, José L.; Lajas, Sara; Melo, Raquel

2017-07-01

Approaches used to assess shallow slide susceptibility at the basin scale are conceptually different depending on the use of statistical or physically based methods. The former are based on the assumption that the same causes are more likely to produce the same effects, whereas the latter are based on the comparison between forces which tend to promote movement along the slope and the counteracting forces that are resistant to motion. Within this general framework, this work tests two hypotheses: (i) although conceptually and methodologically distinct, the statistical and deterministic methods generate similar shallow slide susceptibility results regarding the model's predictive capacity and spatial agreement; and (ii) the combination of shallow slide susceptibility maps obtained with statistical and physically based methods, for the same study area, generate a more reliable susceptibility model for shallow slide occurrence. These hypotheses were tested at a small test site (13.9 km2) located north of Lisbon (Portugal), using a statistical method (the information value method, IV) and a physically based method (the infinite slope method, IS). The landslide susceptibility maps produced with the statistical and deterministic methods were combined into a new landslide susceptibility map. The latter was based on a set of integration rules defined by the cross tabulation of the susceptibility classes of both maps and analysis of the corresponding contingency tables. The results demonstrate a higher predictive capacity of the new shallow slide susceptibility map, which combines the independent results obtained with statistical and physically based models. Moreover, the combination of the two models allowed the identification of areas where the results of the information value and the infinite slope methods are contradictory. Thus, these areas were classified as uncertain and deserve additional investigation at a more detailed scale.

A History of Repeated Failures: Stratigraphy of the Currituck and Cape Fear Slide Complexes on the Central U.S. Atlantic Margin

NASA Astrophysics Data System (ADS)

Hill, J. C.; Brothers, D. S.; Ten Brink, U. S.

2016-12-01

The Currituck and Cape Fear Slide complexes, offshore of North Carolina, are two of the largest (>150 km3) submarine slope failure provinces on the U.S. Atlantic margin. Detailed stratigraphy of these slides and the surrounding regions is derived from a combination of high-resolution sparker multichannel seismic (MCS) data collected by the USGS in 2012, airgun MCS collected as part of the NSF GeoPRISMs Community Seismic Experiment in 2014 & legacy industry airgun MCS data collected in 1970s and 80s. Both the Currituck and Cape Fear Slide complexes are located in regions with high sediment input that resulted in the development of a broad, low gradient (<6°) margin with thick slope sediment accumulation since at least the Miocene. Bedding parallel failure planes highlight the influence of subsurface stratigraphy here. Differential compaction across buried scarps and other erosional surfaces found in proximity to many of the headwalls may have contributed to excess pore pressure in these zones, setting the stage for repeated failures. Within the Currituck Slide complex, there appear to be several buried mass transport deposits (MTDs) within both the Quaternary and Pliocene sections that may be related to buried scarps found beneath both the upper and lower headwalls. At the Cape Fear Slide, the Quaternary section upslope of a large salt diapir displays evidence of possible downslope creep folding within strata that downlap onto a possible buried failure plane. While submarine slope failure along this portion of the margin has long been linked with hydrate dissociation and/or salt tectonics, features that are pervasive along the margin, our new stratigraphic analyses suggest that antecedent margin physiography and sediment loading may be critical factors in determining the locations of large-scale slope failures.

Detailed analysis of the Valdes slide: a landward facing slope failure off Chile

NASA Astrophysics Data System (ADS)

Anasetti, Andrea; Krastel, Sebastian; Weinrebe, Willy; Klaucke, Ingo; Bialas, Jorge

2010-05-01

The Chilean continental margin is a very active area interested by important tectonic movements and characterized by a fast morphological evolution. Geophysical data acquired during cruise JC 23, aboard RV JAMES COOK in March/April 2008 and previous cruises cover most of the active Chilean continental margin between 33° and 37° S. Integrated interpretation of multi-beam bathymetric, sub-bottom profiles, side-scan sonar and seismic data allowed the identification of a number of slope failures. The main topic of this project is the morphological and sedimentological analysis of the Valdes slide, a medium-sized submarine landslide offshore the city of Talcahuano (300 km south of Santiago). In contrast to most other slides along continental margins, the Valdes slide is located on the landward facing eastern slope of a submarine ridge. This setting has important implications for the associated tsunami wave field (first arrival of positive amplitude). We measured geometrical parameters of the failure and adjacent slope. The slide affected an area of 19 km2 between ~1060 m and >1700 m water depths. Its is ~ 6 km long, up to 3 km wide and involved a total sedimentary volume of about 0,8 km3. The failure process was characterized by a multiple-event and we assume its tsunami potential to be high. Using the high resolution bathymetric data and the seismic profiles along the slide deposit it was possible to reconstruct the original morphology of the area in order to understand the relation between the slide event and the structural evolution of the ridge. Through the analysis of the data and bibliographic information about the Chilean margin, we analyzed potential trigger mechanisms for the landslide. The Valdes slide is situated on a steep ridge flank. The ridge follows an elongated fault zone running app. parallel to the margin. This fault zone has a dextral component which in combination with the faults elongation results in a compressional regime that is superimposed on the overall subduction-related compression and ultimately generated this ridge. Over-steepening (slope angle >6° ) of rapidly accumulated sediments (high sedimentation rate) and the huge uplift of the ridge seem to be the most important preconditioning factors of this slide. Seismic data and core analysis suggest that a weak layer acted as sliding surface. The most likely trigger can be assumed one of the frequently occurring strong earthquakes in this area.

Parallel resonant converter with LLC-type commutation

NASA Astrophysics Data System (ADS)

Lee, C. Q.; Liu, Rui; Batarseh, Issa

1989-11-01

It is shown that by using a proper transformation of state variables, the third-order system of the parallel resonant converter (PRC) with LLC-type commutation can be analyzed by means of a two-dimensional state-plane diagram. A set of characteristic curves which can be used for the converter design is derived from the analysis. It is shown from these curves that the converter possesses more desirable features than the conventional PRC.

The dynamic response of Kennicott Glacier, Alaska, USA, to the Hidden Creek Lake outburst flood

USGS Publications Warehouse

Anderson, R. Scott; Walder, J.S.; Anderson, S.P.; Trabant, D.C.; Fountain, A.G.

2005-01-01

Glacier sliding is commonly linked with elevated water pressure at the glacier bed. Ice surface motion during a 3 week period encompassing an outburst of ice-dammed Hidden Creek Lake (HCL) at Kennicott Glacier, Alaska, USA, showed enhanced sliding during the flood. Two stakes, 1.2 km from HCL, revealed increased speed in two episodes, both associated with uplift of the ice surface relative to the trajectory of bed-parallel motion. Uplift of the surface began 12 days before the flood, initially stabilizing at a value of 0.25 m. Two days after lake drainage began, further uplift (reaching 0.4 m) occurred while surface speed peaked at 1.2 m d-1. Maximum surface uplift coincided with peak discharge from HCL, high water level in a down-glacier ice-marginal basin, and low solute concentrations in the Kennicott River. Each of these records is consistent with high subglacial water pressure. We interpret the ice surface motion as arising from sliding up backs of bumps on the bed, which enlarges cavities and produces bed separation. The outburst increased water pressure over a broad region, promoting sliding, inhibiting cavity closure, and blocking drainage of solute-rich water from the distributed system. Pressure drop upon termination of the outburst drained water from and depressurized the distributed system, reducing sliding speeds. Expanded cavities then collapsed with a 1 day time-scale set by the local ice thickness.

Learning pathology using collaborative vs. individual annotation of whole slide images: a mixed methods trial.

PubMed

Sahota, Michael; Leung, Betty; Dowdell, Stephanie; Velan, Gary M

2016-12-12

Students in biomedical disciplines require understanding of normal and abnormal microscopic appearances of human tissues (histology and histopathology). For this purpose, practical classes in these disciplines typically use virtual microscopy, viewing digitised whole slide images in web browsers. To enhance engagement, tools have been developed to enable individual or collaborative annotation of whole slide images within web browsers. To date, there have been no studies that have critically compared the impact on learning of individual and collaborative annotations on whole slide images. Junior and senior students engaged in Pathology practical classes within Medical Science and Medicine programs participated in cross-over trials of individual and collaborative annotation activities. Students' understanding of microscopic morphology was compared using timed online quizzes, while students' perceptions of learning were evaluated using an online questionnaire. For senior medical students, collaborative annotation of whole slide images was superior for understanding key microscopic features when compared to individual annotation; whilst being at least equivalent to individual annotation for junior medical science students. Across cohorts, students agreed that the annotation activities provided a user-friendly learning environment that met their flexible learning needs, improved efficiency, provided useful feedback, and helped them to set learning priorities. Importantly, these activities were also perceived to enhance motivation and improve understanding. Collaborative annotation improves understanding of microscopic morphology for students with sufficient background understanding of the discipline. These findings have implications for the deployment of annotation activities in biomedical curricula, and potentially for postgraduate training in Anatomical Pathology.

A Frequency-Domain Implementation of a Sliding-Window Traffic Sign Detector for Large Scale Panoramic Datasets

NASA Astrophysics Data System (ADS)

Creusen, I. M.; Hazelhoff, L.; De With, P. H. N.

2013-10-01

In large-scale automatic traffic sign surveying systems, the primary computational effort is concentrated at the traffic sign detection stage. This paper focuses on reducing the computational load of particularly the sliding window object detection algorithm which is employed for traffic sign detection. Sliding-window object detectors often use a linear SVM to classify the features in a window. In this case, the classification can be seen as a convolution of the feature maps with the SVM kernel. It is well known that convolution can be efficiently implemented in the frequency domain, for kernels larger than a certain size. We show that by careful reordering of sliding-window operations, most of the frequency-domain transformations can be eliminated, leading to a substantial increase in efficiency. Additionally, we suggest to use the overlap-add method to keep the memory use within reasonable bounds. This allows us to keep all the transformed kernels in memory, thereby eliminating even more domain transformations, and allows all scales in a multiscale pyramid to be processed using the same set of transformed kernels. For a typical sliding-window implementation, we have found that the detector execution performance improves with a factor of 5.3. As a bonus, many of the detector improvements from literature, e.g. chi-squared kernel approximations, sub-class splitting algorithms etc., can be more easily applied at a lower performance penalty because of an improved scalability.

Comprehensive investigation of submarine slide zones and mass movements at the northern continental slope of South China Sea

NASA Astrophysics Data System (ADS)

Chen, Hongjun; Liang, Jin; Gong, Yuehua

2018-02-01

Multi-beam bathymetry and seismic sequence surveys in the northern slope of the South China Sea reveal detailed geomorphology and seismic stratigraphy characteristics of canyons, gullies, and mass movements. Modern canyons and gullies are roughly elongated NNW-SSW with U-shaped cross sections at water depths of 400-1000 m. Mass movements include slide complexes, slide scars, and debris/turbidity flows. Slide complexes and slide scars are oriented in the NE-SW direction and cover an area of about 1790 and 926 km2, respectively. The debris/turbidity flows developed along the lower slope. A detailed facies analysis suggests that four seismic facies exist, and the late Cenozoic stratigraphy above the acoustic basement can be roughly subdivided into three sequences separated by regional unconformities in the study area. The occurrence of gas hydrates is marked by seismic velocity anomalies, bottom-simulating reflectors, gas chimneys, and pockmarks in the study area. Seismic observations suggest that modern canyons and mass movements formed around the transition between the last glacial period and the current interglacial period. The possible existence and dissociation of gas hydrates and the regional tectonic setting may trigger instability and mass movements on the seafloor. Canyons may be the final result of gas hydrate dissociation. Our study aims to contribute new information that is applicable to engineering construction required for deep-water petroleum exploration and gas hydrate surveys along any marginal sea.

Triggering factor evolution and dynamic process simulation of the Formosa Highway dip-slope failure, northern Taiwan

NASA Astrophysics Data System (ADS)

Huang, Mei-Jen; Chiang, Yi-Lin; Chang, Ho-Shyang; Chang, Kuo-Jen

2013-04-01

Taiwan, due to the high seismicity and high annual rainfall, numerous landslides triggered every year and severe impacts affect the island. Accordingly, if the new-built construction does not take into account this threaten, tremendous disasters will occur. On April 25th 2010, Formosa Freeway dip-slope failure caused four deaths, resulted from artificial slope cutting and rock-bot supporting system weakening. This research integrates high resolution Digital Terrain Model (DTM) and numerical simulation to evaluate the triggering mechanism and dynamic process of the landslide. First of all, to access the landslide geometry, the morphology of the event before and after landslide is constructed from high resolution DTM by means of aerial photos. The slid and the deposit volumes of the landslide are thus estimated accordingly. Only part of the surface of separation between slide block and slide slope is exposed. Based on the exposed planar strata/sliding surface, situated on the upper part of the slope, by means of extrapolating part of the plane to mimic the entire slide surface. From DTMs, the slide block is approximately 0.15 million cubic meters. The extrapolated planar surface serves as sliding surface for the numerical models. For numerical model preparation, the particle clusters produced by isotropic stress and the porosity are take into account. To ensure the production range should cover the entire slid mass from the source area, the particle clusters represent the slid block is been rotated, scaled and translated to the source area. Then, part of the particles are been eliminated if it is situated outside the upper and lower surface from the DTM before and after landslide. According to the geological map, the model of the particles to mimic the slide block can be divided into two parts: 1) the underneath interbedded sandstone and shale which may soften by water 2) the supposed upper layer composed of sandstone. Furthermore, set up a layer of particles to simulate ground anchor. The advantages of DTM collocate PFC3d are that real terrain can be represented on the model, and can be simulated the complete landslide process dynamically. Comparing with continuum mechanic analysis that only provides state of instability, but by using discrete element method it can provide the dynamical process of sliding include trajectory, velocity change, sliding distance and also accumulation patterns after landslide and know the affected areas from the disaster event. Results shows: 1) the peak and the residual frictional angle of the sliding surface should be small than 14 and 4 degree, respectively, in the condition of 30% effective resistance of rock-bolt remains. 2)The maximum sliding speed could be as high as 15.34 m/s, caused thus hazard event.

Ten simple rules for Lightning and PechaKucha presentations.

NASA Astrophysics Data System (ADS)

Lortie, C. J.

2016-12-01

An interesting opportunity has emerged that bridges the gap between lengthy, detailed presentations of scientific findings and `sound bites' appropriate for media reporting - very short presentations often presented in sets. Lightning or Ignite (20 slides @15 seconds each) and PechaKucha (20 slides @20 seconds each) presentations are common formats for short, rapid communications at scientific conferences and public events. The simple rules for making good presentations also apply, but these presentation formats provide both unique communication opportunities and novel challenges. In the spirit of light, quick, and exact (but without the fox), here are ten simple rules for presentation formats that do not wait for the speaker.

Practical quantification of necrosis in histological whole-slide images.

PubMed

Homeyer, André; Schenk, Andrea; Arlt, Janine; Dahmen, Uta; Dirsch, Olaf; Hahn, Horst K

2013-06-01

Since the histological quantification of necrosis is a common task in medical research and practice, we evaluate different image analysis methods for quantifying necrosis in whole-slide images. In a practical usage scenario, we assess the impact of different classification algorithms and feature sets on both accuracy and computation time. We show how a well-chosen combination of multiresolution features and an efficient postprocessing step enables the accurate quantification necrosis in gigapixel images in less than a minute. The results are general enough to be applied to other areas of histological image analysis as well. Copyright © 2013 Elsevier Ltd. All rights reserved.

Semi-active sliding mode control of vehicle suspension with magneto-rheological damper

NASA Astrophysics Data System (ADS)

Zhang, Hailong; Wang, Enrong; Zhang, Ning; Min, Fuhong; Subash, Rakheja; Su, Chunyi

2015-01-01

The vehicle semi-active suspension with magneto-rheological damper(MRD) has been a hot topic since this decade, in which the robust control synthesis considering load variation is a challenging task. In this paper, a new semi-active controller based upon the inverse model and sliding mode control (SMC) strategies is proposed for the quarter-vehicle suspension with the magneto-rheological (MR) damper, wherein an ideal skyhook suspension is employed as the control reference model and the vehicle sprung mass is considered as an uncertain parameter. According to the asymptotical stability of SMC, the dynamic errors between the plant and reference systems are used to derive the control damping force acquired by the MR quarter-vehicle suspension system. The proposed modified Bouc-wen hysteretic force-velocity ( F- v) model and its inverse model of MR damper, as well as the proposed continuous modulation (CM) filtering algorithm without phase shift are employed to convert the control damping force into the direct drive current of the MR damper. Moreover, the proposed semi-active sliding mode controller (SSMC)-based MR quarter-vehicle suspension is systematically evaluated through comparing the time and frequency domain responses of the sprung and unsprung mass displacement accelerations, suspension travel and the tire dynamic force with those of the passive quarter-vehicle suspension, under three kinds of varied amplitude harmonic, rounded pulse and real-road measured random excitations. The evaluation results illustrate that the proposed SSMC can greatly suppress the vehicle suspension vibration due to uncertainty of the load, and thus improve the ride comfort and handling safety. The study establishes a solid theoretical foundation as the universal control scheme for the adaptive semi-active control of the MR full-vehicle suspension decoupled into four MR quarter-vehicle sub-suspension systems.

A superconducting homopolar motor and generator—new approaches

NASA Astrophysics Data System (ADS)

Fuger, Rene; Matsekh, Arkadiy; Kells, John; Sercombe, D. B. T.; Guina, Ante

2016-03-01

Homopolar machines were the first continuously running electromechanical converters ever demonstrated but engineering challenges and the rapid development of AC technology prevented wider commercialisation. Recent developments in superconducting, cryogenic and sliding contact technology together with new areas of application have led to a renewed interest in homopolar machines. Some of the advantages of these machines are ripple free constant torque, pure DC operation, high power-to-weight ratio and that rotating magnets or coils are not required. In this paper we present our unique approach to high power and high torque homopolar electromagnetic turbines using specially designed high field superconducting magnets and liquid metal current collectors. The unique arrangement of the superconducting coils delivers a high static drive field as well as effective shielding for the field critical sliding contacts. The novel use of additional shielding coils reduces weight and stray field of the system. Liquid metal current collectors deliver a low resistance, stable and low maintenance sliding contact by using a thin liquid metal layer that fills a circular channel formed by the moving edge of a rotor and surrounded by a conforming stationary channel of the stator. Both technologies are critical to constructing high performance machines. Homopolar machines are pure DC devices that utilise only DC electric and magnetic fields and have no AC losses in the coils or the supporting structure. Guina Energy Technologies has developed, built and tested different motor and generator concepts over the last few years and has combined its experience to develop a new generation of homopolar electromagnetic turbines. This paper summarises the development process, general design parameters and first test results of our high temperature superconducting test motor.

Selectivity of Vibrio cholerae H-NOX for Gaseous Ligands Follows “Sliding Scale Rule” Hypothesis

PubMed Central

Wu, Gang; Liu, Wen; Berka, Vladimir; Tsai, Ah-lim

2014-01-01

Vc H-NOX (or VCA0720) is an H-NOX (heme-nitric oxide and oxygen binding) protein from facultative aerobic bacterium Vibrio cholerae. It shares significant sequence homology with soluble guanylyl cyclase (sGC), a NO sensor protein commonly found in animals. Similar to sGC, Vc H-NOX binds strongly to NO and CO with affinities of 0.27 nM and 0.77 μM, respectively, but weakly to O2. When positioned in “sliding scale” plot {Tsai, A.-L. et. al. (2012) Biochemistry, 51, pp172-86}, the line connecting logKD(NO) and logKD(CO) of Vc H-NOX is almost superimposable with that of Ns H-NOX. Therefore, the measured affinities and kinetic parameters of gaseous ligands to Vc H-NOX provide more evidence to validate the “sliding scale rule” hypothesis. Like sGC, Vc H-NOX binds NO in multiple steps, forming first a 6-coordinate heme-NO complex with a rate of 1.1 × 109 M−1s−1, and then converts to a 5c heme-NO complex at a rate also dependent on [NO]. Although the formation of oxyferrous Vc H-NOX is not detectable under normal atmospheric oxygen level, ferrous Vc H-NOX is oxidized to ferric form at a rate of 0.06 s−1 when mixed with O2. Ferric Vc H-NOX exists as a mixture of high- and low-spin states and is influenced by binding to different ligands. Characterization of both ferric and ferrous Vc H-NOX and their complexes with various ligands lay the foundation for understanding the possible dual roles in gas and redox sensing of Vc H-NOX. PMID:24351060

Textural development of clayey and quartzofeldspathic fault gouges relative to their sliding behavior

USGS Publications Warehouse

Moore, Diane E.; Byerlee, J.D.

1990-01-01

Many of the secondary fault structures developed during triaxial friction experiments have been generally correlated with the structures of natural fault zones. Therefore, any physical differences that can be found between laboratory samples that slide stably and those that show stick-slip motion may help to identify the cause of earthquakes. We have examined petrographically the run products of many triaxial friction experiments using clayey and quartzofeldspathic gouges, which comprise the principal types of natural fault gouge material. The examined samples were tested under a wide range of temperature, confining and fluid pressure, and velocity conditions. The clayey and quartzofeldspathic gouges show some textural differences, owing to their different mineral contents and grain sizes and shapes. In the clayey gouges, for example, a clay mineral fabric and kink band sets are commonly developed, whereas in the quartzofeldspathic gouges fracturing and crushing of the predominately quartz and feldspar grains are important processes. For both types of gouge, however, and whatever the pressure-temperature-velocity conditions of the experiments, the transition from stable sliding to stick-slip motion is correlated with: (i) a change from pervasive deformation of the gouge layer to localized slip in subsidiary shears; and (ii) an increase in the angle betweem the shears that crosscut the gouge layer (Riedel shears) and ones that form along the gouge-rock cylinder boundaries (boundary shears). This suggests that the localization of shear within a fault zone combined with relatively high Riedel-shear angles are somehow connected with earthquakes. Secondary fracture sets similar to Riedel shears have been identified at various scales in major strike-slip faults such as the San Andreas of the western United States (Wallace, 1973) and the Luhuo and Fuyun earthquake faults of China (Deng and Zhang, 1984; Deng et al., 1986). The San Andreas also contains locked and creeping sections that correspond to the stick-slip and stably sliding experimental samples, respectively. We plan to study the physical structure of the San Andreas fault, to see if the experimentally observed differences related to sliding behavior can also be distinguished in the field. ?? 1990.

Tissue Photolithography

NASA Technical Reports Server (NTRS)

Wade, Lawrence A.; Kartalov, Emil; Shibata, Darryl; Taylor, Clive

2011-01-01

Tissue lithography will enable physicians and researchers to obtain macromolecules with high purity (greater than 90 percent) from desired cells in conventionally processed, clinical tissues by simply annotating the desired cells on a computer screen. After identifying the desired cells, a suitable lithography mask will be generated to protect the contents of the desired cells while allowing destruction of all undesired cells by irradiation with ultraviolet light. The DNA from the protected cells can be used in a number of downstream applications including DNA sequencing. The purity (i.e., macromolecules isolated form specific cell types) of such specimens will greatly enhance the value and information of downstream applications. In this method, the specific cells are isolated on a microscope slide using photolithography, which will be faster, more specific, and less expensive than current methods. It relies on the fact that many biological molecules such as DNA are photosensitive and can be destroyed by ultraviolet irradiation. Therefore, it is possible to protect the contents of desired cells, yet destroy undesired cells. This approach leverages the technologies of the microelectronics industry, which can make features smaller than 1 micrometer with photolithography. A variety of ways has been created to achieve identification of the desired cell, and also to designate the other cells for destruction. This can be accomplished through chrome masks, direct laser writing, and also active masking using dynamic arrays. Image recognition is envisioned as one method for identifying cell nuclei and cell membranes. The pathologist can identify the cells of interest using a microscopic computerized image of the slide, and appropriate custom software. In one of the approaches described in this work, the software converts the selection into a digital mask that can be fed into a direct laser writer, e.g. the Heidelberg DWL66. Such a machine uses a metalized glass plate (with chrome metallization) on which there is a thin layer of photoresist. The laser transfers the digital mask onto the photoresist by direct writing, with typical best resolution of 2 micrometers. The plate is then developed to remove the exposed photoresist, which leaves the exposed areas susceptible to chemical chrome etch. The etch removes the unprotected chrome. The rest of the photoresist is then removed, by either ultraviolet organic solvent or over-development. The remaining chrome pattern is quickly oxidized by atmospheric exposure (typically within 30 seconds). The ready chrome mask is now applied to the tissue slide and aligned manually, or using automatic software and pre-designed alignment marks. The slide plate sandwich is then exposed to UV to destroy the DNA of the unwanted cells. The slide and plate are separated and the slide is processed in a standard way to prepare for polymerase chain reaction (PCR) and potential identification of cancer sequences.

Meteorites for K-12 Classrooms: NASA Meteorite Educational Materials

NASA Astrophysics Data System (ADS)

Lindstrom, M.; Allen, J.

1995-09-01

The fall of a new meteorite is an event that catches the interest of the public in matters of science. The threat of a huge impact like last year's comet Shoemaker-Levy 9 gives us all reason to evaluate such potential risks. NASA's meteorite educational materials use our natural interest in rocks from space to present classroom activities on planetary science. The meteorite educational package includes a meteorite sample disk, a teachers's guide and a slide set. The sample disk is a lucite disk containing chips of six different kinds of meteorites (3 chondrites, achondrite, iron, stony-iron). EXPLORING METEORITE MYSTERIES is a teacher's guide with background information and 19 hands-on or heads-on activities for grades 4-12. It was prepared in a partnership of planetary scientists and teachers. The slide set consists of 48 slides with captions to be used with the activities. The materials will be available in Fall 1995. Teachers may obtain a loan of the whole package from NASA Teacher Resource Centers; researchers may borrow them from the JSC meteorite curator. The booklet is available separately from the same sources, and the slide set will be available from NASA CORE. EXPLORING METEORITE MYSTERIES is an interdisciplinary planetary science unit which teaches basic science concepts and techniques together with math, reading, writing and social studies The activities are done in a variety of different teaching styles which emphasize observation, experimentation and critical thinking. The activities are ideal for middle schools where teaming makes interdisciplinary units desireable, but most of the activities can be easily modified for grade levels from upper elementary through high school. Meteorites are a natural subject for interdisciplinary teaching because their study involves all fields of science and offers fascinating historical accounts and possibilities for creative expression. Topics covered in EXPLORING METEORITE MYSTERES are centered around basic questions: Where did they come from? What are they? How did they form? How do they affect people? The unit begins with the story of two boys who observed the fall of the Noblesville meteorite in 1991 and concludes with activities on using space resources, careers, and tabloid science. The NASA meteorite educational materials provide teachers with information, activities and slides to use meteorites to teach the interdisciplinary science of the solar system. It also provides planetary scientists with activities to take to local schools and ideas for sharing their knowledge with their communities.

New side-view imaging technique for observing posterior chamber structures during cataract surgery in porcine eyes

PubMed Central

2013-01-01

Background To develop a side-view imaging technique for observing the dynamic behavior of posterior chamber structures (PCSs) in porcine eyes which mimics closed-eye cataract surgery in humans. Methods Enucleated porcine eyes were placed into liquid nitrogen for 5 seconds and immediately bisected at about a 45-degree angle to the equatorial plane. The anterior portion was attached firmly to a glass slide with superglue and sprinkled with wheat flour. Phacoemulsification and aspiration (PEA) was performed as in humans on 10 consecutive porcine eyes. The movements of the PCSs were monitored through the glass slide with a high-resolution video camera set below the cut surface of the eye. The intraocular pressure (IOP) was monitored during the surgery. The highest IOP, operation time, and volume of irrigation fluid of 10 whole eyes were compared to that obtained from the bisected eyes glued to a glass slide. In a second set of experiments, the strength of the seal between the bisected eye and the glass slide was tested in three sets of eyes: 1) frozen eye fixed with superglue with wheat flour for 3 min; 2) frozen eye fixed with superglue for 3 min; and 3) non-frozen eye fixed with superglue for 30 min. The highest IOP that led to a disruption of the seal was compared among the three groups. Results PEA was successfully performed on 9 of 10 (90%) eyes with the movements of the PCSs clearly observed. The average maximum intraocular pressure of the 9 bisected eyes was 55.8 ± 4.7 mmHg and that for the 10 unbisected eyes was 55.3 ± 5.0 mmHg (P = 0.650). The frozen eye fixed with superglue in combination with wheat flour (Group 1) had the strongest sealing strength with an average IOP at the breaking point of 117.3 ± 36.2 mmHg. Conclusions Our side-view imaging technique can be used to evaluate the changes of the PCSs during intraocular surgery and for surgical training of new residents. PMID:24053470

Mutation of the myosin converter domain alters cross-bridge elasticity

PubMed Central

Köhler, Jan; Winkler, Gerhard; Schulte, Imke; Scholz, Tim; McKenna, William; Brenner, Bernhard; Kraft, Theresia

2002-01-01

Elastic distortion of a structural element of the actomyosin complex is fundamental to the ability of myosin to generate motile forces. An elastic element allows strain to develop within the actomyosin complex (cross-bridge) before movement. Relief of this strain then drives filament sliding, or more generally, movement of a cargo. Even with the known crystal structure of the myosin head, however, the structural element of the actomyosin complex in which elastic distortion occurs remained unclear. To assign functional relevance to various structural elements of the myosin head, e.g., to identify the elastic element within the cross-bridge, we studied mechanical properties of muscle fibers from patients with familial hypertrophic cardiomyopathy with point mutations in the head domain of the β-myosin heavy chain. We found that the Arg-719 → Trp (Arg719Trp) mutation, which is located in the converter domain of the myosin head fragment, causes an increase in force generation and fiber stiffness under isometric conditions by 48–59%. Under rigor and relaxing conditions, fiber stiffness was 45–47% higher than in control fibers. Yet, kinetics of active cross-bridge cycling were unchanged. These findings, especially the increase in fiber stiffness under rigor conditions, indicate that cross-bridges with the Arg719Trp mutation are more resistant to elastic distortion. The data presented here strongly suggest that the converter domain that forms the junction between the catalytic and the light-chain-binding domain of the myosin head is not only essential for elastic distortion of the cross-bridge, but that the main elastic distortion may even occur within the converter domain itself. PMID:11904418

Indentation theory on a half-space of transversely isotropic multi-ferroic composite medium: sliding friction effect

NASA Astrophysics Data System (ADS)

Wu, F.; Wu, T.-H.; Li, X.-Y.

2018-03-01

This article aims to present a systematic indentation theory on a half-space of multi-ferroic composite medium with transverse isotropy. The effect of sliding friction between the indenter and substrate is taken into account. The cylindrical flat-ended indenter is assumed to be electrically/magnetically conducting or insulating, which leads to four sets of mixed boundary-value problems. The indentation forces in the normal and tangential directions are related to the Coulomb friction law. For each case, the integral equations governing the contact behavior are developed by means of the generalized method of potential theory, and the corresponding coupling field is obtained in terms of elementary functions. The effect of sliding on the contact behavior is investigated. Finite element method (FEM) in the context of magneto-electro-elasticity is developed to discuss the validity of the analytical solutions. The obtained analytical solutions may serve as benchmarks to various simplified analyses and numerical codes and as a guide for future experimental studies.

Correlation between automatic detection of malaria on thin film and experts' parasitaemia scores

NASA Astrophysics Data System (ADS)

Sunarko, Budi; Williams, Simon; Prescott, William R.; Byker, Scott M.; Bottema, Murk J.

2017-03-01

An algorithm was developed to diagnose the presence of malaria and to estimate the depth of infection by automatically counting individual normal and infected erythrocytes in images of thin blood smears. During the training stage, the parameters of the algorithm were optimized to maximize correlation with estimates of parasitaemia from expert human observers. The correlation was tested on a set of 1590 images from seven thin film blood smears. The correlation between the results from the algorithm and expert human readers was r = 0.836. Results indicate that reliable estimates of parasitaemia may be achieved by computational image analysis methods applied to images of thin film smears. Meanwhile, compared to biological experiments, the algorithm fitted well the three high parasitaemia slides and a mid-level parasitaemia slide, and overestimated the three low parasitaemia slides. To improve the parasitaemia estimation, the sources of the overestimation were identified. Emphasis is laid on the importance of further research in order to identify parasites independently of their erythrocyte hosts

Classification, Properties, and Management of Aridisols.

ERIC Educational Resources Information Center

Mack, C. B.; And Others

1990-01-01

Described is a slide set which is designed to illustrate the entire range of soils found in the arid regions of the earth's surface. Information on physical and chemical soil properties, soil classification, and related soil management considerations for agricultural development are included. (CW)

Developing an Approach for Analyzing and Verifying System Communication

NASA Technical Reports Server (NTRS)

Stratton, William C.; Lindvall, Mikael; Ackermann, Chris; Sibol, Deane E.; Godfrey, Sally

2009-01-01

This slide presentation reviews a project for developing an approach for analyzing and verifying the inter system communications. The motivation for the study was that software systems in the aerospace domain are inherently complex, and operate under tight constraints for resources, so that systems of systems must communicate with each other to fulfill the tasks. The systems of systems requires reliable communications. The technical approach was to develop a system, DynSAVE, that detects communication problems among the systems. The project enhanced the proven Software Architecture Visualization and Evaluation (SAVE) tool to create Dynamic SAVE (DynSAVE). The approach monitors and records low level network traffic, converting low level traffic into meaningful messages, and displays the messages in a way the issues can be detected.

Cleanroom Garment Silicone Contamination

NASA Technical Reports Server (NTRS)

Geer, Wayne; Lepage, Colette

2006-01-01

The slide presentation reviews actions taken at Goddard Space Flight Center (GSFC) to eliminate contamination by silicone in clean rooms. Background information includes facilities and hardware affected by silicon contamination, a discussion of the negative aspects of silicone contamination, clean room garments, and how the problem was identified at GSFC. Actions taken by the GSFC Contamination Engineering Group and lessons learned are detailed. Results include: awareness of the silicone issue in laundry, increase in infrastructure and support of the testing lab, establishment of protocols for garment verification, closer relationship established with laundry and converter, specifications for laundry services and garments were strengthened, all consumables are tested before use in clean rooms, and established procedures were used to identify and treat silicone found on face masks.

Speed-Selector Guard For Machine Tool

NASA Technical Reports Server (NTRS)

Shakhshir, Roda J.; Valentine, Richard L.

1992-01-01

Simple guardplate prevents accidental reversal of direction of rotation or sudden change of speed of lathe, milling machine, or other machine tool. Custom-made for specific machine and control settings. Allows control lever to be placed at only one setting. Operator uses handle to slide guard to engage or disengage control lever. Protects personnel from injury and equipment from damage occurring if speed- or direction-control lever inadvertently placed in wrong position.

Preliminary evaluation of a fully automated quantitative framework for characterizing general breast tissue histology via color histogram and color texture analysis

NASA Astrophysics Data System (ADS)

Keller, Brad M.; Gastounioti, Aimilia; Batiste, Rebecca C.; Kontos, Despina; Feldman, Michael D.

2016-03-01

Visual characterization of histologic specimens is known to suffer from intra- and inter-observer variability. To help address this, we developed an automated framework for characterizing digitized histology specimens based on a novel application of color histogram and color texture analysis. We perform a preliminary evaluation of this framework using a set of 73 trichrome-stained, digitized slides of normal breast tissue which were visually assessed by an expert pathologist in terms of the percentage of collagenous stroma, stromal collagen density, duct-lobular unit density and the presence of elastosis. For each slide, our algorithm automatically segments the tissue region based on the lightness channel in CIELAB colorspace. Within each tissue region, a color histogram feature vector is extracted using a common color palette for trichrome images generated with a previously described method. Then, using a whole-slide, lattice-based methodology, color texture maps are generated using a set of color co-occurrence matrix statistics: contrast, correlation, energy and homogeneity. The extracted features sets are compared to the visually assessed tissue characteristics. Overall, the extracted texture features have high correlations to both the percentage of collagenous stroma (r=0.95, p<0.001) and duct-lobular unit density (r=0.71, p<0.001) seen in the tissue samples, and several individual features were associated with either collagen density and/or the presence of elastosis (p<=0.05). This suggests that the proposed framework has promise as a means to quantitatively extract descriptors reflecting tissue-level characteristics and thus could be useful in detecting and characterizing histological processes in digitized histology specimens.

Enhanced distributed energy resource system

DOEpatents

Atcitty, Stanley [Albuquerque, NM; Clark, Nancy H [Corrales, NM; Boyes, John D [Albuquerque, NM; Ranade, Satishkumar J [Las Cruces, NM

2007-07-03

A power transmission system including a direct current power source electrically connected to a conversion device for converting direct current into alternating current, a conversion device connected to a power distribution system through a junction, an energy storage device capable of producing direct current connected to a converter, where the converter, such as an insulated gate bipolar transistor, converts direct current from an energy storage device into alternating current and supplies the current to the junction and subsequently to the power distribution system. A microprocessor controller, connected to a sampling and feedback module and the converter, determines when the current load is higher than a set threshold value, requiring triggering of the converter to supply supplemental current to the power transmission system.

Stability of Molasse: TLS for structural analysis in the valley of Gotteron-Fribourg, Switzerland

NASA Astrophysics Data System (ADS)

Ben Hammouda, Mariam; Jaboyedoff, Michel; Derron, Marc Henri; Bouaziz, Samir; Mazotti, Benoit

2016-04-01

The marine molasses of Fribourg (Switzerland) is an area where the cliff collapses and rockfalls are quite frequent and difficult to predict due to this particular lithology, a poorly consolidated greywacke. Because of some recent rockfall events, the situation became critical especially in the valley of Gotteron where a big block has slightly moved down and might destroy a house in case of rupture. The cliff made of jointed sandstone and thin layers of clay and siltstone presents many fractures, joints and massive cross bedding surfaces which increases the possibility of slab failure. This paper presents a detailed structural analysis of the cliff and the identification of the potential failure mechanisms. The methodology is about combining field observation and terrestrial LiDAR scanning point cloud in order to assess the stability of potential slope instabilities of molasses. Three LiDAR scans were done i) to extract discontinuity families depending to the dip and the dip direction of joints and ii) to run kinematic tests in order to identify responsible sets for each potential failure mechanisms. Raw point clouds were processed using IMAlign module of Polyworks and CloudCompare software. The structural analysis based on COLTOP 3D (Jaboyedoff et al. 2007) allowed the identification of four discontinuity sets that were not measured in the field. Two different failure mechanisms have been identified as critical: i) planar sliding which is the main responsible mechanism of the present fallen block and ii) wedge sliding. The planar sliding is defined by the discontinuity sets J1 and J5 with a direction parallel to the slope and with a steep dip angle. The wedges, defined by couples of discontinuity sets, contribute to increase cracks' opening and to the detachment of slabs. The use of TLS combined with field survey provides us a first interpretation of instabilities and a very promising structural analysis.

Convolutional neural networks for an automatic classification of prostate tissue slides with high-grade Gleason score

NASA Astrophysics Data System (ADS)

Jiménez del Toro, Oscar; Atzori, Manfredo; Otálora, Sebastian; Andersson, Mats; Eurén, Kristian; Hedlund, Martin; Rönnquist, Peter; Müller, Henning

2017-03-01

The Gleason grading system was developed for assessing prostate histopathology slides. It is correlated to the outcome and incidence of relapse in prostate cancer. Although this grading is part of a standard protocol performed by pathologists, visual inspection of whole slide images (WSIs) has an inherent subjectivity when evaluated by different pathologists. Computer aided pathology has been proposed to generate an objective and reproducible assessment that can help pathologists in their evaluation of new tissue samples. Deep convolutional neural networks are a promising approach for the automatic classification of histopathology images and can hierarchically learn subtle visual features from the data. However, a large number of manual annotations from pathologists are commonly required to obtain sufficient statistical generalization when training new models that can evaluate the daily generated large amounts of pathology data. A fully automatic approach that detects prostatectomy WSIs with high-grade Gleason score is proposed. We evaluate the performance of various deep learning architectures training them with patches extracted from automatically generated regions-of-interest rather than from manually segmented ones. Relevant parameters for training the deep learning model such as size and number of patches as well as the inclusion or not of data augmentation are compared between the tested deep learning architectures. 235 prostate tissue WSIs with their pathology report from the publicly available TCGA data set were used. An accuracy of 78% was obtained in a balanced set of 46 unseen test images with different Gleason grades in a 2-class decision: high vs. low Gleason grade. Grades 7-8, which represent the boundary decision of the proposed task, were particularly well classified. The method is scalable to larger data sets with straightforward re-training of the model to include data from multiple sources, scanners and acquisition techniques. Automatically generated heatmaps for theWSIs could be useful for improving the selection of patches when training networks for big data sets and to guide the visual inspection of these images.

Multivariate classification of the infrared spectra of cell and tissue samples

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

Haaland, D.M.; Jones, H.D.; Thomas, E.V.

1997-03-01

Infrared microspectroscopy of biopsied canine lymph cells and tissue was performed to investigate the possibility of using IR spectra coupled with multivariate classification methods to classify the samples as normal, hyperplastic, or neoplastic (malignant). IR spectra were obtained in transmission mode through BaF{sub 2} windows and in reflection mode from samples prepared on gold-coated microscope slides. Cytology and histopathology samples were prepared by a variety of methods to identify the optimal methods of sample preparation. Cytospinning procedures that yielded a monolayer of cells on the BaF{sub 2} windows produced a limited set of IR transmission spectra. These transmission spectra weremore » converted to absorbance and formed the basis for a classification rule that yielded 100{percent} correct classification in a cross-validated context. Classifications of normal, hyperplastic, and neoplastic cell sample spectra were achieved by using both partial least-squares (PLS) and principal component regression (PCR) classification methods. Linear discriminant analysis applied to principal components obtained from the spectral data yielded a small number of misclassifications. PLS weight loading vectors yield valuable qualitative insight into the molecular changes that are responsible for the success of the infrared classification. These successful classification results show promise for assisting pathologists in the diagnosis of cell types and offer future potential for {ital in vivo} IR detection of some types of cancer. {copyright} {ital 1997} {ital Society for Applied Spectroscopy}« less

Morphological texture assessment of oral bone as a screening tool for osteoporosis

NASA Astrophysics Data System (ADS)

Analoui, Mostafa; Eggertsson, Hafsteinn; Eckert, George

2001-07-01

Three classes of texture analysis approaches have been employed to assess the textural characteristic of oral bone. A set of linear structuring elements was used to compute granulometric features of trabecular bone. Multifractal analysis was also used to compute the fractal dimension of the corresponding tissues. In addition, some statistical features and histomorphometric parameters were computed. To assess the proposed approach we acquired digital intraoral radiographs of 47 subjects (14 males and 33 females). All radiographs were captured at 12 bits/pixel. Images were converted to binary form through a sliding locally adaptive thresholding approach. Each subject was scanned by DEXA for bone dosimetry. Subject were classified into one of the following three categories according World Health Organization (WHO) standard (1) healthy, (2) with osteopenia and (3) osteoporosis. In this study fractal dimension showed very low correlation with bone mineral density (BMD) measurements, which did not reach a level of statistical significance (p<0.5). However, entropy of pattern spectrum (EPS), along with statistical features and histomorphometric parameters, has shown correlation coefficients ranging from low to high, with statistical significance for both males and females. The results of this study indicate the utility of this approach for bone texture analysis. It is conjectured that designing a 2-D structuring element, specially tuned to trabecular bone texture, will increase the efficacy of the proposed method.

Seismic isolation of nuclear power plants using sliding isolation bearings

NASA Astrophysics Data System (ADS)

Kumar, Manish

Nuclear power plants (NPP) are designed for earthquake shaking with very long return periods. Seismic isolation is a viable strategy to protect NPPs from extreme earthquake shaking because it filters a significant fraction of earthquake input energy. This study addresses the seismic isolation of NPPs using sliding bearings, with a focus on the single concave Friction Pendulum(TM) (FP) bearing. Friction at the sliding surface of an FP bearing changes continuously during an earthquake as a function of sliding velocity, axial pressure and temperature at the sliding surface. The temperature at the sliding surface, in turn, is a function of the histories of coefficient of friction, sliding velocity and axial pressure, and the travel path of the slider. A simple model to describe the complex interdependence of the coefficient of friction, axial pressure, sliding velocity and temperature at the sliding surface is proposed, and then verified and validated. Seismic hazard for a seismically isolated nuclear power plant is defined in the United States using a uniform hazard response spectrum (UHRS) at mean annual frequencies of exceedance (MAFE) of 10-4 and 10 -5. A key design parameter is the clearance to the hard stop (CHS), which is influenced substantially by the definition of the seismic hazard. Four alternate representations of seismic hazard are studied, which incorporate different variabilities and uncertainties. Response-history analyses performed on single FP-bearing isolation systems using ground motions consistent with the four representations at the two shaking levels indicate that the CHS is influenced primarily by whether the observed difference between the two horizontal components of ground motions in a given set is accounted for. The UHRS at the MAFE of 10-4 is increased by a design factor (≥ 1) for conventional (fixed base) nuclear structure to achieve a target annual frequency of unacceptable performance. Risk oriented calculations are performed for eight sites across the United States to show that the factor is equal to 1.0 for seismically isolated NPPs, if the risk is dominated by horizontal earthquake shaking. Response-history analyses using different models of seismically isolated NPPs are performed to understand the importance of the choice of friction model, model complexity and vertical ground motion for calculating horizontal displacement response across a wide range of sites and shaking intensities. A friction model for the single concave FP bearing should address heating. The pressure- and velocity-dependencies were not important for the models and sites studied. Isolation-system displacements can be computed using a macro model comprising a single FP bearing.

A Duo of Potassium-Responsive Histidine Kinases Govern the Multicellular Destiny of Bacillus subtilis.

PubMed

Grau, Roberto R; de Oña, Paula; Kunert, Maritta; Leñini, Cecilia; Gallegos-Monterrosa, Ramses; Mhatre, Eisha; Vileta, Darío; Donato, Verónica; Hölscher, Theresa; Boland, Wilhelm; Kuipers, Oscar P; Kovács, Ákos T

2015-07-07

Multicellular biofilm formation and surface motility are bacterial behaviors considered mutually exclusive. However, the basic decision to move over or stay attached to a surface is poorly understood. Here, we discover that in Bacillus subtilis, the key root biofilm-controlling transcription factor Spo0A~Pi (phosphorylated Spo0A) governs the flagellum-independent mechanism of social sliding motility. A Spo0A-deficient strain was totally unable to slide and colonize plant roots, evidencing the important role that sliding might play in natural settings. Microarray experiments plus subsequent genetic characterization showed that the machineries of sliding and biofilm formation share the same main components (i.e., surfactin, the hydrophobin BslA, exopolysaccharide, and de novo-formed fatty acids). Sliding proficiency was transduced by the Spo0A-phosphorelay histidine kinases KinB and KinC. We discovered that potassium, a previously known inhibitor of KinC-dependent biofilm formation, is the specific sliding-activating signal through a thus-far-unnoticed cytosolic domain of KinB, which resembles the selectivity filter sequence of potassium channels. The differential expression of the Spo0A~Pi reporter abrB gene and the different levels of the constitutively active form of Spo0A, Sad67, in Δspo0A cells grown in optimized media that simultaneously stimulate motile and sessile behaviors uncover the spatiotemporal response of KinB and KinC to potassium and the gradual increase in Spo0A~Pi that orchestrates the sequential activation of sliding, followed by sessile biofilm formation and finally sporulation in the same population. Overall, these results provide insights into how multicellular behaviors formerly believed to be antagonistic are coordinately activated in benefit of the bacterium and its interaction with the host. Alternation between motile and sessile behaviors is central to bacterial adaptation, survival, and colonization. However, how is the collective decision to move over or stay attached to a surface controlled? Here, we use the model plant-beneficial bacterium Bacillus subtilis to answer this question. Remarkably, we discover that sessile biofilm formation and social sliding motility share the same structural components and the Spo0A regulatory network via sensor kinases, KinB and KinC. Potassium, an inhibitor of KinC-dependent biofilm formation, triggers sliding via a potassium-perceiving cytosolic domain of KinB that resembles the selectivity filter of potassium channels. The spatiotemporal response of these kinases to variable potassium levels and the gradual increase in Spo0A~Pi levels that orchestrates the activation of sliding before biofilm formation shed light on how multicellular behaviors formerly believed to be antagonistic work together to benefit the population fitness. Copyright © 2015 Grau et al.

Direct detection of Mycobacterium tuberculosis rifampin resistance in bio-safe stained sputum smears.

PubMed

Lavania, Surabhi; Anthwal, Divya; Bhalla, Manpreet; Singh, Nagendra; Haldar, Sagarika; Tyagi, Jaya Sivaswami

2017-01-01

Direct smear microscopy of sputum forms the mainstay of TB diagnosis in resource-limited settings. Stained sputum smear slides can serve as a ready-made resource to transport sputum for molecular drug susceptibility testing. However, bio-safety is a major concern during transport of sputum/stained slides and for laboratory workers engaged in processing Mycobacterium tuberculosis infected sputum specimens. In this study, a bio-safe USP (Universal Sample Processing) concentration-based sputum processing method (Bio-safe method) was assessed on 87 M. tuberculosis culture positive sputum samples. Samples were processed for Ziehl-Neelsen (ZN) smear, liquid culture and DNA isolation. DNA isolated directly from sputum was subjected to an IS6110 PCR assay. Both sputum DNA and DNA extracted from bio-safe ZN concentrated smear slides were subjected to rpoB PCR and simultaneously assessed by DNA sequencing for determining rifampin (RIF) resistance. All sputum samples were rendered sterile by Bio-safe method. Bio-safe smears exhibited a 5% increment in positivity over direct smear with a 14% increment in smear grade status. All samples were positive for IS6110 and rpoB PCR. Thirty four percent samples were RIF resistant by rpoB PCR product sequencing. A 100% concordance (κ value = 1) was obtained between sequencing results derived from bio-safe smear slides and bio-safe sputum. This study demonstrates that Bio-safe method can address safety issues associated with sputum processing, provide an efficient alternative to sample transport in the form of bio-safe stained concentrated smear slides and can also provide information on drug (RIF) resistance by direct DNA sequencing.

Direct detection of Mycobacterium tuberculosis rifampin resistance in bio-safe stained sputum smears

PubMed Central

Lavania, Surabhi; Anthwal, Divya; Bhalla, Manpreet; Singh, Nagendra; Haldar, Sagarika; Tyagi, Jaya Sivaswami

2017-01-01

Direct smear microscopy of sputum forms the mainstay of TB diagnosis in resource-limited settings. Stained sputum smear slides can serve as a ready-made resource to transport sputum for molecular drug susceptibility testing. However, bio-safety is a major concern during transport of sputum/stained slides and for laboratory workers engaged in processing Mycobacterium tuberculosis infected sputum specimens. In this study, a bio-safe USP (Universal Sample Processing) concentration-based sputum processing method (Bio-safe method) was assessed on 87 M. tuberculosis culture positive sputum samples. Samples were processed for Ziehl-Neelsen (ZN) smear, liquid culture and DNA isolation. DNA isolated directly from sputum was subjected to an IS6110 PCR assay. Both sputum DNA and DNA extracted from bio-safe ZN concentrated smear slides were subjected to rpoB PCR and simultaneously assessed by DNA sequencing for determining rifampin (RIF) resistance. All sputum samples were rendered sterile by Bio-safe method. Bio-safe smears exhibited a 5% increment in positivity over direct smear with a 14% increment in smear grade status. All samples were positive for IS6110 and rpoB PCR. Thirty four percent samples were RIF resistant by rpoB PCR product sequencing. A 100% concordance (κ value = 1) was obtained between sequencing results derived from bio-safe smear slides and bio-safe sputum. This study demonstrates that Bio-safe method can address safety issues associated with sputum processing, provide an efficient alternative to sample transport in the form of bio-safe stained concentrated smear slides and can also provide information on drug (RIF) resistance by direct DNA sequencing. PMID:29216262

New insights into the timing, triggers and emplacement processes of prodigious submarine landslides in the Nordic Seas

NASA Astrophysics Data System (ADS)

Talling, Peter; Pope, Ed; Hunt, James; Allin, Joshua; Cartigny, Matthieu; Long, David; Mozzato, Alessandro; Stanford, Jennifer; Tappin, David; Watts, Camilla

2015-04-01

Submarine landslides can generate tsunamis with the potential to cause severe damage. This is illustrated by the huge (> 3,000 cubic km) Storegga landslide offshore Norway that occurred 8,200 years ago, and which produced a tsunami that ran up surrounding coastlines for up to 20m. Here we report on a 1 month research cruise on the RV Pelagia in July 2014 to the Nordic Seas, which collected 88 sediment cores totalling more than 500m, together with over 7,000 square km of swath bathymetry. The overall aim of this research expedition was to better understand the tsunami risk from large submarine landslides in the Nordic Seas. This includes a better understanding of the timing and frequency of submarine landslides, factors that potentially trigger or precondition slope failure, and the manner in which landslides are emplaced. Much of the expedition was then devoted to understanding the age and emplacement mechanism of the ~900 cubic km Traenadjupet landslide, located to the north of the Storegga Slide. This included sampling and mapping of the main Traenadjupet Slide, four lobes froming the distal Traenadjupet Slide deposit. A newly discovered debris flow deposit with large blocks was found to continue from the most westerly of these lobes, and it was mapped to its termination. If the previously established age of ~4ka for the Traenadjupet Slide is correct, then it does not appear to produced a major tsunami (unlike the Storegga Slide). Indeed, the morphology of the Traenadjupet Slide suggests much slower emplacement than the Storegga Slide, which would be consistent with such a lack of major tsunami. Turbidites in cores from the deep-water Lofoten Basin will help to understand the frequency and character of faster moving slope failures around the basin margin. Cores were collected from the Lofoten Contourite Drift located next to the Traenadjupet Slide, and these contouritic sediment may provide a paleoceanographic record that can be compared to slide timing, in order to determine whether climatic change can trigger major slope failure. A set of cores from the Bear Island Fan were taken to understand timing of deposition on very large volumes of sediment, and loading of continental slopes. This material may also help to understand the past history of the Barents Ice Sheet. Cores were collected in order to date movement on extensive cracklines on the seafloor near to the headwall of the Storegga Slide, to determine whether deformation has continued beyond 8.2ka. The final work off the Aegir Ridge successfully penetrated through a very large mega-turbidite that lies beneath a mega-turbidite formed by the Storegga Slide. Available geophysical data suggests that older mega-bed may be even more voluminous than the Storegga mega-bed, which itself contains ~1,000km3 of sediment. Further work will aim to date this earlier mega-event bed, which will help to understand large landslide timing in the region.

Dynamics of static friction between steel and silicon

PubMed Central

Yang, Zhiping; Zhang, H. P.; Marder, M.

2008-01-01

We conducted experiments in which steel and silicon or quartz are clamped together. Even with the smallest tangential forces we could apply, we always found reproducible sliding motions on the nanometer scale. The velocities we study are thousands of times smaller than in previous investigations. The samples first slide and then lock up even when external forces hold steady. One might call the result “slip-stick” friction. We account for the results with a phenomenological theory that results from considering the rate and state theory of dynamic friction at low velocities. Our measurements lead us to set the instantaneous coefficient of static friction that normally enters rate and state theories to zero. PMID:18768792

Impulse position control algorithms for nonlinear systems

NASA Astrophysics Data System (ADS)

Sesekin, A. N.; Nepp, A. N.

2015-11-01

The article is devoted to the formalization and description of impulse-sliding regime in nonlinear dynamical systems that arise in the application of impulse position controls of a special kind. The concept of trajectory impulse-sliding regime formalized as some limiting network element Euler polygons generated by a discrete approximation of the impulse position control This paper differs from the previously published papers in that it uses a definition of solutions of systems with impulse controls, it based on the closure of the set of smooth solutions in the space of functions of bounded variation. The need for the study of such regimes is the fact that they often arise when parry disturbances acting on technical or economic control system.

Possible Nuclear Safeguards Applications: Workshop on Next-Generation Laser Compton Gamma Source

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

Durham, J. Matthew

2016-11-17

These are a set of slides for the development of a next-generation photon source white paper. The following topics are covered in these slides: Nuclear Safeguards; The Nuclear Fuel Cycle; Precise isotopic determination via NRF; UF 6 Enrichment Assay; and Non-Destructive Assay of Spent Nuclear Fuel. In summary: A way to non-destructively measure precise isotopics of ~kg and larger samples has multiple uses in nuclear safeguards; Ideally this is a compact, fieldable device that can be used by international inspectors. Must be rugged and reliable; A next-generation source can be used as a testing ground for these techniques as technologymore » develops.« less

Development of multichannel soft tactile sensors having fingerprint structure.

PubMed

Tsutsui, H; Murashima, Y; Honma, N; Kobayashi, K

2014-01-01

It is possible to accurately recognize the shape of an object or to grip it by setting soft tactile sensors on a robot's hands. We studied a multichannel soft tactile sensor as an artificial hand and evaluated the pressure's response performance from several directions and the slipping and sliding responses. The tactile sensor consisted of multiple pneumatic sensors and a soft cap with a fingerprint structure that was made of silicone gum and was separated from multiple spaces. Evaluation tests showed that the multiple soft tactile sensors estimate both an object's contact force and its contact location. Our tactile sensor also measured the object's roughness by the slide on surface texture.

78 FR 22263 - Agency Information Collection Activities; Proposed Collection; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-15

... produce effectiveness and comparative effectiveness research. The Effective Health Care Program also... materials and translation products that are currently available are designed to help practicing clinicians... started developing some tools, such as faculty slide sets based on comparative effectiveness reviews of...

The X-Ray Optics for the High Angular Resolution Imager (HARI)

NASA Technical Reports Server (NTRS)

Weisskopf, M. C.

2010-01-01

This slide presentation shows the basic parameters of the x-ray optics, the housing,a graph of the effective area vs energy, another graph showing the angular off-set vs HEW, and a series of graphs showing the detector offsets and tilts,

Astronomical Resources. The Solar System: An Introductory Bibliography.

ERIC Educational Resources Information Center

Fraknoi, Andrew

This reference surveys resources of astronomical information including books and articles about the solar system, Mercury, Venus, Earth, the Moon, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto, Asteroids, Comets, and Meteors. Also included is a list of seven available slide sets about the solar system. (CW)

Adaptive sliding mode back-stepping pitch angle control of a variable-displacement pump controlled pitch system for wind turbines.

PubMed

Yin, Xiu-xing; Lin, Yong-gang; Li, Wei; Liu, Hong-wei; Gu, Ya-jing

2015-09-01

A variable-displacement pump controlled pitch system is proposed to mitigate generator power and flap-wise load fluctuations for wind turbines. The pitch system mainly consists of a variable-displacement hydraulic pump, a fixed-displacement hydraulic motor and a gear set. The hydraulic motor can be accurately regulated by controlling the pump displacement and fluid flows to change the pitch angle through the gear set. The detailed mathematical representation and dynamic characteristics of the proposed pitch system are thoroughly analyzed. An adaptive sliding mode pump displacement controller and a back-stepping stroke piston controller are designed for the proposed pitch system such that the resulting pitch angle tracks its desired value regardless of external disturbances and uncertainties. The effectiveness and control efficiency of the proposed pitch system and controllers have been verified by using realistic dataset of a 750 kW research wind turbine. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Mouse cursor movement and eye tracking data as an indicator of pathologists' attention when viewing digital whole slide images.

PubMed

Raghunath, Vignesh; Braxton, Melissa O; Gagnon, Stephanie A; Brunyé, Tad T; Allison, Kimberly H; Reisch, Lisa M; Weaver, Donald L; Elmore, Joann G; Shapiro, Linda G

2012-01-01

Digital pathology has the potential to dramatically alter the way pathologists work, yet little is known about pathologists' viewing behavior while interpreting digital whole slide images. While tracking pathologist eye movements when viewing digital slides may be the most direct method of capturing pathologists' viewing strategies, this technique is cumbersome and technically challenging to use in remote settings. Tracking pathologist mouse cursor movements may serve as a practical method of studying digital slide interpretation, and mouse cursor data may illuminate pathologists' viewing strategies and time expenditures in their interpretive workflow. To evaluate the utility of mouse cursor movement data, in addition to eye-tracking data, in studying pathologists' attention and viewing behavior. Pathologists (N = 7) viewed 10 digital whole slide images of breast tissue that were selected using a random stratified sampling technique to include a range of breast pathology diagnoses (benign/atypia, carcinoma in situ, and invasive breast cancer). A panel of three expert breast pathologists established a consensus diagnosis for each case using a modified Delphi approach. Participants' foveal vision was tracked using SensoMotoric Instruments RED 60 Hz eye-tracking system. Mouse cursor movement was tracked using a custom MATLAB script. Data on eye-gaze and mouse cursor position were gathered at fixed intervals and analyzed using distance comparisons and regression analyses by slide diagnosis and pathologist expertise. Pathologists' accuracy (defined as percent agreement with the expert consensus diagnoses) and efficiency (accuracy and speed) were also analyzed. Mean viewing time per slide was 75.2 seconds (SD = 38.42). Accuracy (percent agreement with expert consensus) by diagnosis type was: 83% (benign/atypia); 48% (carcinoma in situ); and 93% (invasive). Spatial coupling was close between eye-gaze and mouse cursor positions (highest frequency ∆x was 4.00px (SD = 16.10), and ∆y was 37.50px (SD = 28.08)). Mouse cursor position moderately predicted eye gaze patterns (Rx = 0.33 and Ry = 0.21). Data detailing mouse cursor movements may be a useful addition to future studies of pathologists' accuracy and efficiency when using digital pathology.

PDF Lecture Materials for Online and ``Flipped'' Format Astronomy Courses

NASA Astrophysics Data System (ADS)

Kary, D. M.; Eisberg, J.

2013-04-01

Online astronomy courses typically rely on students reading the textbook and/or a set of text-based lecture notes to replace the “lecture” material. However, many of our students report that this is much less engaging than in-person lectures, especially given the amount of interactive work such as “think-pair-share” problems done in many astronomy classes. Students have similarly criticized direct lecture-capture. To address this, we have developed a set of PowerPoint-style presentations with embedded lecture audio combined with prompts for student interaction including think-pair-share questions. These are formatted PDF packages that can be used on a range of different computers using free software. The presentations are first developed using Microsoft PowerPoint software. Audio recordings of scripted lectures are then synchronized with the presentations and the entire package is converted to PDF using Adobe Presenter. This approach combines the ease of editing that PowerPoint provides along with the platform-independence of PDF. It's easy to add, remove, or edit individual slides as needed, and PowerPoint supports internal links so that think-pair-share questions can be inserted with links to feedback based on the answers selected. Modern PDF files support animated visuals with synchronized audio and they can be read using widely available free software. Using these files students in an online course can get many of the benefits of seeing and hearing the course material presented in an in-person lecture format. Students needing extra help in traditional lecture classes can use these presentations to help review the materials covered in lecture. Finally, the presentations can be used in a “flipped” format in which students work through the presentations outside of class time while spending the “lecture” time on in-class interaction.

Fuzzy CMAC With incremental Bayesian Ying-Yang learning and dynamic rule construction.

PubMed

Nguyen, M N

2010-04-01

Inspired by the philosophy of ancient Chinese Taoism, Xu's Bayesian ying-yang (BYY) learning technique performs clustering by harmonizing the training data (yang) with the solution (ying). In our previous work, the BYY learning technique was applied to a fuzzy cerebellar model articulation controller (FCMAC) to find the optimal fuzzy sets; however, this is not suitable for time series data analysis. To address this problem, we propose an incremental BYY learning technique in this paper, with the idea of sliding window and rule structure dynamic algorithms. Three contributions are made as a result of this research. First, an online expectation-maximization algorithm incorporated with the sliding window is proposed for the fuzzification phase. Second, the memory requirement is greatly reduced since the entire data set no longer needs to be obtained during the prediction process. Third, the rule structure dynamic algorithm with dynamically initializing, recruiting, and pruning rules relieves the "curse of dimensionality" problem that is inherent in the FCMAC. Because of these features, the experimental results of the benchmark data sets of currency exchange rates and Mackey-Glass show that the proposed model is more suitable for real-time streaming data analysis.

Thermionic converter

DOEpatents

Fitzpatrick, G.O.

1987-05-19

A thermionic converter is set forth which includes an envelope having an electron collector structure attached adjacent to a wall. An electron emitter structure is positioned adjacent the collector structure and spaced apart from opposite wall. The emitter and collector structures are in a common chamber. The emitter structure is heated substantially only by thermal radiation. Very small interelectrode gaps can be maintained utilizing the thermionic converter whereby increased efficiency results. 10 figs.

Jig For Stereoscopic Photography

NASA Technical Reports Server (NTRS)

Nielsen, David J.

1990-01-01

Separations between views adjusted precisely for best results. Simple jig adjusted to set precisely, distance between right and left positions of camera used to make stereoscopic photographs. Camera slides in slot between extreme positions, where it takes stereoscopic pictures. Distance between extreme positions set reproducibly with micrometer. In view of trend toward very-large-scale integration of electronic circuits, training method and jig used to make training photographs useful to many companies to reduce cost of training manufacturing personnel.

A statistical overview of mass movement characteristics on the North American Atlantic outer continental margin

USGS Publications Warehouse

Booth, James S.; O'Leary, Dennis W.

1992-01-01

An analysis of 179 mass movements on the North American Atlantic continental slope and upper rise shows that slope failures have occurred throughout the geographic extent of the outer margin. Although the slope failures show no striking affinity for a particular depth as an origination level, there is a broad, primary mode centered at about 900 m. The resulting slides terminate at almost all depths and have a primary mode at 1100 m, but the slope/rise boundary (at 2200 m) also is an important mode. Slope failures have occurred at declivities ranging from 1° to 30° (typically, 4°); the resultant mass movement deposits vary in width from 0.2 to 50 km (typically, 1-2 km) and in length from 0.3 to 380 km (typically, 2–4 km), and they have been reported to be as thick as 650 m. On a numeric basis, mass movements are slightly more prevalent on open slopes than in other physiographic settings, and both translational and rotational failure surfaces are common. The typical mass movement is disintegrative in nature. Open slope slides tend to occur at lower slope angles and are larger than canyon slides. Further, large‐scale slides rather than small‐scale slides tend to originate on gentle slopes (≍ 3-4°). Rotational slope failures appear to have a slightly greater chance of occurring in canyons, but there is no analogous bias associated with translational failures. Similarly, disintegrative slides seem more likely to be associated with rotational slope failures than translational ones and are longer than their nondisintegrative counterparts. The occurrence of such a variety of mass movements at low declivities implies that a regional failure mechanism has prevailed. We suggest that earthquakes or, perhaps in some areas, gas hydrates are the most likely cause of the slope failures.

Overview of EPA Office of Research and Development (ORD) Research Activities Related to Nanomaterials

EPA Science Inventory

The product is the presentation - a draft set of slides is attached. The presentation is organized around a comprehensive framework for nanomaterial evaluation published last year (Boyes et al., 2017). The framework considers nanomaterial enabled products across their life span...

78 FR 5805 - Agency Information Collection Activities: Proposed Collection; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-28

... comparative effectiveness research. The Effective Health Care Program also translates research findings into a... that are currently available are designed to help practicing clinicians, consumers/patients, and..., such as faculty slide sets based on comparative effectiveness reviews of the literature, to reach this...

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

Funk, David John

The topic is presented in a series of slides arranged according to the following outline: LANL nitrate salt incident as thermal runaway (thermally sensitive surrogates, full-scale tests), temperature control for processing, treatment options and down selection, assessment of engineering options, anticipated control set for treatment, and summary of the overall steps for RNS.

NASA SMD and DPS Resources for Higher Education Faculty

NASA Astrophysics Data System (ADS)

Buxner, Sanlyn; Grier, Jennifer; Meinke, Bonnie; Schneider, Nick; Low, Rusty; Schultz, Greg; Manning, James; Fraknoi, Andrew; Gross, Nicholas

2015-11-01

The NASA Education and Public Outreach Forums have developed and provided resources for higher education for the past six years through a cooperative agreement with NASA’s Science Mission Directorate. Collaborations with science organizations, including AAS’s Division of Planetary Sciences, have resulted in more tools, professional training opportunities, and dissemination of resources for teaching in the undergraduate classroom. Resources have been developed through needs assessments of the community and with input from scientists and undergraduate instructors. All resources are freely available.NASA Wavelength (nasawavelength.org) is a collection of digital peer reviewed Earth and space science resources for formal and informal educators of all levels. All resources were developed through funding of the NASA Science Mission Directorate and have undergone a peer-review process through which educators and scientists ensure the content is accurate and useful in an educational setting. Within NASA Wavelength are specific lists of activities and resources for higher education faculty. Additionally, several resources have been developed for introductory college classrooms. The DPS Discovery slide sets are 3-slide presentations that can be incorporated into college lectures to keep classes apprised of the fast moving field of planetary science (http://dps.aas.org/education/dpsdisc). The “Astro 101 slide sets”, developed by the Astro Forum, are presentations 5-7 slides in length on a new development or discovery from a NASA Astrophysics mission relevant to topics in introductory astronomy courses of discoveries not yet in textbooks. Additional resources guides are available for Astro 101 courses and include cosmology and exoplanets. (https://www.astrosociety.org/education/resources-for-the-higher-education-audience/).Professional development opportunities are available to faculty to increase content knowledge and pedagogical tools. These include workshops at scientific meetings and online webinars that are archived for later viewing. For more information, visit the SMD E/PO community workspace at http://smdepo.org.

Space technology putting it in the educational perspective

NASA Technical Reports Server (NTRS)

Hankins, D. B.

1975-01-01

One of the precepts of the company was to provide educators with practical, innovative, and manageable audio-visual teaching aids in a wide spectrum of educational fields, but primarily geography, geology and social science. A pilot slide set was prepared, demonstrating primary areas along the entire length of the San Andreas Fault Zone in California and Mexico. This set utilized several NASA infrared research aircraft photos, to more clearly delineate fault traces. A decision was made to mount a massive program of repackaging NASA generated infrared aircraft imagery into topical teaching sets.

Automatic Nuclei Segmentation in H&E Stained Breast Cancer Histopathology Images

PubMed Central

Veta, Mitko; van Diest, Paul J.; Kornegoor, Robert; Huisman, André; Viergever, Max A.; Pluim, Josien P. W.

2013-01-01

The introduction of fast digital slide scanners that provide whole slide images has led to a revival of interest in image analysis applications in pathology. Segmentation of cells and nuclei is an important first step towards automatic analysis of digitized microscopy images. We therefore developed an automated nuclei segmentation method that works with hematoxylin and eosin (H&E) stained breast cancer histopathology images, which represent regions of whole digital slides. The procedure can be divided into four main steps: 1) pre-processing with color unmixing and morphological operators, 2) marker-controlled watershed segmentation at multiple scales and with different markers, 3) post-processing for rejection of false regions and 4) merging of the results from multiple scales. The procedure was developed on a set of 21 breast cancer cases (subset A) and tested on a separate validation set of 18 cases (subset B). The evaluation was done in terms of both detection accuracy (sensitivity and positive predictive value) and segmentation accuracy (Dice coefficient). The mean estimated sensitivity for subset A was 0.875 (±0.092) and for subset B 0.853 (±0.077). The mean estimated positive predictive value was 0.904 (±0.075) and 0.886 (±0.069) for subsets A and B, respectively. For both subsets, the distribution of the Dice coefficients had a high peak around 0.9, with the vast majority of segmentations having values larger than 0.8. PMID:23922958

Automatic nuclei segmentation in H&E stained breast cancer histopathology images.

PubMed

Veta, Mitko; van Diest, Paul J; Kornegoor, Robert; Huisman, André; Viergever, Max A; Pluim, Josien P W

2013-01-01

The introduction of fast digital slide scanners that provide whole slide images has led to a revival of interest in image analysis applications in pathology. Segmentation of cells and nuclei is an important first step towards automatic analysis of digitized microscopy images. We therefore developed an automated nuclei segmentation method that works with hematoxylin and eosin (H&E) stained breast cancer histopathology images, which represent regions of whole digital slides. The procedure can be divided into four main steps: 1) pre-processing with color unmixing and morphological operators, 2) marker-controlled watershed segmentation at multiple scales and with different markers, 3) post-processing for rejection of false regions and 4) merging of the results from multiple scales. The procedure was developed on a set of 21 breast cancer cases (subset A) and tested on a separate validation set of 18 cases (subset B). The evaluation was done in terms of both detection accuracy (sensitivity and positive predictive value) and segmentation accuracy (Dice coefficient). The mean estimated sensitivity for subset A was 0.875 (±0.092) and for subset B 0.853 (±0.077). The mean estimated positive predictive value was 0.904 (±0.075) and 0.886 (±0.069) for subsets A and B, respectively. For both subsets, the distribution of the Dice coefficients had a high peak around 0.9, with the vast majority of segmentations having values larger than 0.8.

High resolution computational on-chip imaging of biological samples using sparsity constraint (Conference Presentation)

NASA Astrophysics Data System (ADS)

Rivenson, Yair; Wu, Chris; Wang, Hongda; Zhang, Yibo; Ozcan, Aydogan

2017-03-01

Microscopic imaging of biological samples such as pathology slides is one of the standard diagnostic methods for screening various diseases, including cancer. These biological samples are usually imaged using traditional optical microscopy tools; however, the high cost, bulkiness and limited imaging throughput of traditional microscopes partially restrict their deployment in resource-limited settings. In order to mitigate this, we previously demonstrated a cost-effective and compact lens-less on-chip microscopy platform with a wide field-of-view of >20-30 mm^2. The lens-less microscopy platform has shown its effectiveness for imaging of highly connected biological samples, such as pathology slides of various tissue samples and smears, among others. This computational holographic microscope requires a set of super-resolved holograms acquired at multiple sample-to-sensor distances, which are used as input to an iterative phase recovery algorithm and holographic reconstruction process, yielding high-resolution images of the samples in phase and amplitude channels. Here we demonstrate that in order to reconstruct clinically relevant images with high resolution and image contrast, we require less than 50% of the previously reported nominal number of holograms acquired at different sample-to-sensor distances. This is achieved by incorporating a loose sparsity constraint as part of the iterative holographic object reconstruction. We demonstrate the success of this sparsity-based computational lens-less microscopy platform by imaging pathology slides of breast cancer tissue and Papanicolaou (Pap) smears.

Repeated Measurements on Distinct Scales With Censoring—A Bayesian Approach Applied to Microarray Analysis of Maize

PubMed Central

Love, Tanzy; Carriquiry, Alicia

2009-01-01

We analyze data collected in a somatic embryogenesis experiment carried out on Zea mays at Iowa State University. The main objective of the study was to identify the set of genes in maize that actively participate in embryo development. Embryo tissue was sampled and analyzed at various time periods and under different mediums and light conditions. As is the case in many microarray experiments, the operator scanned each slide multiple times to find the slide-specific ‘optimal’ laser and sensor settings. The multiple readings of each slide are repeated measurements on different scales with differing censoring; they cannot be considered to be replicate measurements in the traditional sense. Yet it has been shown that the choice of reading can have an impact on genetic inference. We propose a hierarchical modeling approach to estimating gene expression that combines all available readings on each spot and accounts for censoring in the observed values. We assess the statistical properties of the proposed expression estimates using a simulation experiment. As expected, combining all available scans using an approach with good statistical properties results in expression estimates with noticeably lower bias and root mean squared error relative to other approaches that have been proposed in the literature. Inferences drawn from the somatic embryogenesis experiment, which motivated this work changed drastically when data were analyzed using the standard approaches or using the methodology we propose. PMID:19960120

Performance of Landslide-HySEA tsunami model for NTHMP benchmarking validation process

NASA Astrophysics Data System (ADS)

Macias, Jorge

2017-04-01

In its FY2009 Strategic Plan, the NTHMP required that all numerical tsunami inundation models be verified as accurate and consistent through a model benchmarking process. This was completed in 2011, but only for seismic tsunami sources and in a limited manner for idealized solid underwater landslides. Recent work by various NTHMP states, however, has shown that landslide tsunami hazard may be dominant along significant parts of the US coastline, as compared to hazards from other tsunamigenic sources. To perform the above-mentioned validation process, a set of candidate benchmarks were proposed. These benchmarks are based on a subset of available laboratory date sets for solid slide experiments and deformable slide experiments, and include both submarine and subaerial slides. A benchmark based on a historic field event (Valdez, AK, 1964) close the list of proposed benchmarks. The Landslide-HySEA model has participated in the workshop that was organized at Texas A&M University - Galveston, on January 9-11, 2017. The aim of this presentation is to show some of the numerical results obtained for Landslide-HySEA in the framework of this benchmarking validation/verification effort. Acknowledgements. This research has been partially supported by the Junta de Andalucía research project TESELA (P11-RNM7069), the Spanish Government Research project SIMURISK (MTM2015-70490-C02-01-R) and Universidad de Málaga, Campus de Excelencia Internacional Andalucía Tech. The GPU computations were performed at the Unit of Numerical Methods (University of Malaga).

Benchmarking Multilayer-HySEA model for landslide generated tsunami. HTHMP validation process.

NASA Astrophysics Data System (ADS)

Macias, J.; Escalante, C.; Castro, M. J.

2017-12-01

Landslide tsunami hazard may be dominant along significant parts of the coastline around the world, in particular in the USA, as compared to hazards from other tsunamigenic sources. This fact motivated NTHMP about the need of benchmarking models for landslide generated tsunamis, following the same methodology already used for standard tsunami models when the source is seismic. To perform the above-mentioned validation process, a set of candidate benchmarks were proposed. These benchmarks are based on a subset of available laboratory data sets for solid slide experiments and deformable slide experiments, and include both submarine and subaerial slides. A benchmark based on a historic field event (Valdez, AK, 1964) close the list of proposed benchmarks. A total of 7 benchmarks. The Multilayer-HySEA model including non-hydrostatic effects has been used to perform all the benchmarking problems dealing with laboratory experiments proposed in the workshop that was organized at Texas A&M University - Galveston, on January 9-11, 2017 by NTHMP. The aim of this presentation is to show some of the latest numerical results obtained with the Multilayer-HySEA (non-hydrostatic) model in the framework of this validation effort.Acknowledgements. This research has been partially supported by the Spanish Government Research project SIMURISK (MTM2015-70490-C02-01-R) and University of Malaga, Campus de Excelencia Internacional Andalucía Tech. The GPU computations were performed at the Unit of Numerical Methods (University of Malaga).

Geo-structural modelling for potential large rock slide in Machu Picchu

NASA Astrophysics Data System (ADS)

Spizzichino, D.; Delmonaco, G.; Margottini, C.; Mazzoli, S.

2009-04-01

The monumental complex of the Historical Sanctuary of Machu Picchu, declared as World Heritage Site by UNESCO in 1983, is located in the Andean chain at approx. 80 km from Cuzco (Peru) and at an elevation of 2430 m a.s.l. along the Urubamba River Valley. From a geological point of view, the Machu Picchu granitoid pluton, forming part of the larger "Quillabamba granite", is one of a series of plutons intruded along the axial zone of the high Eastern Cordillera Permo-Liassic rift system including a variety of rock types, dominantly granites and granodiorites. The most evident structures at the outcrop scale consist of planar joint sets that may be variably reactivated and exhibiting 4 main orientations. At present, the site is affected by geological risk due to frequent landslides that threaten security and tourist exploitation. In the last years, the international landslide scientific community has promoted a multi-discipline joint programme mainly finalised to slope deformation monitoring and analysis after the warning, launched in 2001, of a potential collapse of the citadel, caused by a huge rock slide. The contribute of the Italian research team was devoted to implement a landslide risk analysis and an innovative remote sensing techniques. The main scope of this work is to present the implementation of a geo-structural modelling aimed at defining present and potential slope stability conditions of the Machu Picchu Citadel. Data have been collected by geological, structural and geomechanical field surveys and laboratory tests in order to reconstruct the geomorphological evolution of the area. Landslide types and evolution are strictly controlled by regional tectonic uplift and structural setting. Several slope instability phenomena have been identified and classified according to mechanism, material involved and state of activity. Rock falls, debris flows, rock slides and debris slides are the main surveyed landslide types. Rock slides and rock falls may produce blocks with dimensions variable from 10-1 to 102m3 that form the toe accumulation on steeper slopes. The area of the citadel has also been interpreted as affected by a deep mass movement (>100m) that, if confirmed by the present day monitoring systems, could be referred to a deep-seated gravitational slope deformation (DSGSD), probably of the type of the compound bi-planar sagging (CB) described by Hutchinson (1988). The analysis of active strain processes (e.g. tension cracks) along with the damage pattern surveyed on archaeological structures (e.g. sinking, swelling, tilting) suggest that the potential failure of a large rock slide may be located at a depth of ca. 30m. The various data sets have been integrated in order to obtain a general geo-structural and geotechnical model (strength and deformation parameters, seismic input) of the citadel at the slope scale. This represents a first step in implementing a slope stability analysis capable of reconstructing present and potential landslide evolution under static and dynamic conditions. This multi-discipline study, based on geological and structural analysis integrated with geotechnical and geomechanical interpretation, will aid defining actual landslide hazard and risk levels, indispensable for the design of low impact mitigation measures to be applied at Machu Picchu Citadel.

[Digital pathology : The time has come!

PubMed

Grobholz, R

2018-05-01

Digital pathology (DP) and whole-slide imaging (WSI) technology have matured substantially over the last few years. Meanwhile, commercial systems are available that can be used in routine practice. Illustration of DP experiences in a routine diagnostic setting. A DP system offers several advantages: 1) glass slides are no longer unique; 2) access to cases is possible from any location; 3) digital image analysis can be applied; and 4) archived WSI can be easily accessed. From this point, several secondary advantages arise: a) the slide compilation of the case and the case assignment is fast and safe; b) carrying cases to the pathologist is obsolete and paperless work is possible; c) WSI can be used for a second opinion and be accessible in remote locations; d) WSI of referred cases are still accessible after returning the slides; e) histological images can easily be provided in tumor boards; f) the office desk is clean; and g) a "home office" is possible. To introduce a DP system, a comprehensive workflow analysis is needed that clarifies the needs and wishes of the respective institute. In order to optimally meet the requirements, open DP platforms are of particular advantage, because they enable the integration of scanners from various manufacturers. Further developments in image analysis, such as virtual tissue reconstruction, could enrich the diagnostic process in the future and improve treatment quality.

The virtual microscopy database-sharing digital microscope images for research and education.

PubMed

Lee, Lisa M J; Goldman, Haviva M; Hortsch, Michael

2018-02-14

Over the last 20 years, virtual microscopy has become the predominant modus of teaching the structural organization of cells, tissues, and organs, replacing the use of optical microscopes and glass slides in a traditional histology or pathology laboratory setting. Although virtual microscopy image files can easily be duplicated, creating them requires not only quality histological glass slides but also an expensive whole slide microscopic scanner and massive data storage devices. These resources are not available to all educators and researchers, especially at new institutions in developing countries. This leaves many schools without access to virtual microscopy resources. The Virtual Microscopy Database (VMD) is a new resource established to address this problem. It is a virtual image file-sharing website that allows researchers and educators easy access to a large repository of virtual histology and pathology image files. With the support from the American Association of Anatomists (Bethesda, MD) and MBF Bioscience Inc. (Williston, VT), registration and use of the VMD are currently free of charge. However, the VMD site is restricted to faculty and staff of research and educational institutions. Virtual Microscopy Database users can upload their own collection of virtual slide files, as well as view and download image files for their own non-profit educational and research purposes that have been deposited by other VMD clients. Anat Sci Educ. © 2018 American Association of Anatomists. © 2018 American Association of Anatomists.

Power dissipation in the mixed metal-insulator state of self-heated VO2 single crystals and the effect of sliding domains

NASA Astrophysics Data System (ADS)

Fisher, B.; Patlagan, L.

2018-06-01

The mixed metal-insulator state in VO2 sets on within the current-controlled negative differential resistivity regime of I-V loops traced at ambient temperature. In this state, the stability of I(V) and/or spontaneous switching between initial and final steady states are governed by the load resistance RL in series with the sample. With increasing current (decreasing voltage), the power P = IV reaches a maximum (Pmax) and drops to a minimum (Pmin) along a path that depends on RL. For low enough RL, the ratio Pmax/Pmin may exceed by far the contrast in thermal emissivity from films of VO2 over the metal-insulator transition as reported in Kats et al. [Phys. Rev. X 3, 041004 (2013)]. The minimum is followed by a range of currents where the power increases with current. The return path overlaps the original path and continues towards backward switching. For a few samples, there is evidence from optical microscopy that the portion of the P(I) loop between Pmin and backward switching coincides with the range of currents where semiconducting domains slide within a metallic background. Damage induced in crystals by repeated I-V cycling suppresses domain sliding and flattens P(I) in the respective range of currents. This is consistent with the current dependent excess power dissipation being induced by the sliding domains.

Improvement of McKibben Artificial Muscle with Long Stroke Motion and Its Application

NASA Astrophysics Data System (ADS)

Akagi, Tetsuya; Dohta, Shujiro; Kuno, Hiroaki; Ihara, Michinori

The actuators required for a wearable system need to be flexible so as not to injure the body. The purpose of this study is to develop a flexible and lightweight actuator which can be safe enough to be attached to the human body. In the previous study, a new type of McKibben artificial muscle that had a long stroke of more than 80 % of its original length was proposed and tested. However, the damages on the tube of the actuator were found. They are caused by a large friction between the slide stage and the tube. Therefore, the life time of the actuator becomes shorter. In this paper, the improved McKibben actuator which consists of a McKibben artificial muscle on the market (FESTO Co. Ltd.), steel balls as a cylinder head and two pairs of slide stages is proposed and tested. The slide stage has steel balls set on the inner bore of the stage to decrease the friction. The steel ball in the McKibben actuator is held by two pairs of slide stages from both sides of the ball. As a result, the minimum driving pressure of the improved actuator decreases about 68 % compared with that of the previous one. The actuator can realize both pushing and pulling motion even if it has flexibility. By using these properties of the actuator, the various rehabilitation devices were proposed and tested.

Effects of modifying the World Health Organization standard operating procedures for malaria microscopy to improve surveillance in resource poor settings.

PubMed

Fernando, Sumadhya D; Ihalamulla, Ratnasiri L; Wickremasinghe, Renu; de Silva, Nipun L; Thilakarathne, Janani H; Wijeyaratne, Pandu; Premaratne, Risintha G

2014-03-15

Individuals with fever are screened for malaria in specially-established malaria diagnostic laboratories set up in rural hospitals in the Northern and Eastern Provinces of Sri Lanka. Large numbers of blood smears negative for malaria parasites are being screened daily. Good quality smears are essential to maintain a high diagnostic competency among the technical staff. The modifications made to the World Health Organization (WHO) standard operating procedures to improve the quality of smears have been studied. A blinded, controlled, interventional study was conducted in 22 intervention and 21 control malaria diagnostic laboratories. Changes were made to the WHO standard operating procedure protocols to prepare, stain and examine blood smears for malaria parasite detection which were implemented in intervention laboratories. These included wipe-cleaning slides, preparing both thick and thin smears on the same slide, reversing the order of collecting blood for thick and thin smears, dry fixing thick smear for 20-25 minutes under table lamp, polishing the edge of spreader slide with sand paper and fixing the thin smear with methanol if not stained within four hours. Parameters with respect to quality of the smear as per WHO criteria were studied using randomly selected slides, and time taken for the report to be issued was recorded in both groups before and after the intervention. There were no significant differences observed in the parameters studied at baseline between the two groups or pre and post intervention in the control group. In the intervention group streak formation in thin smears was reduced from 29.4% to 5.0%. The average fixing time of thick smears was reduced from 2.4 hours to 20 minutes. Inappropriate thickness of thick smears reduced from 18.3% to 1.5%. Overall quality of thick smears and thin smears increased from 76.1% to 98.0% and 81.7% to 87.0%, respectively. The quality of slides bearing both thick and thin smears increased from 60.0% to 87.0%. New protocols with amendments to the WHO standard technical procedures ensure that good quality blood smears are prepared rapidly to diagnose malaria and the time required to issue the reports was reduced.

Futuristics for Today's Student: A Course Description.

ERIC Educational Resources Information Center

Aanestad, Naedine

The humanities course described in this paper encourages high school students to examine alternatives for the future and to make decisions on the basis of the most desirable outcomes. Classroom instructional materials include films, sound and slide sets, film strips, tape recorders, a record player, and a television. Students participate in…

Design and Implementation of a Simulation-Based Learning System for International Trade

ERIC Educational Resources Information Center

Luo, Guo-Heng; Liu, Eric Zhi-Feng; Kuo, Hung-Wei; Yuan, Shyan-Ming

2014-01-01

In the traditional instructional method used in international trade, teachers provide knowledge to learners by lecturing using slides and setting assignments; however, these methods merely deliver international trade knowledge rather than facilitating student development of relevant skills. To solve these problems, we proposed a simulation-based…

(Mis)Understanding Radiation

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

Schreiber, Stephen Bruce

2016-02-10

This set of slides discusses radiation and fears concerning it at a non-technical level. Included are some misconceptions and practical consequences resulting from these. The concept of radiation hormesis is explained. The author concludes that a number of significant societal benefits are being foregone because of overly cautious concerns about low-level radiation.

The Classical Performing Arts of India.

ERIC Educational Resources Information Center

Curtiss, Marie Joy

A monograph of the numerous activities that have contributed to the current renaissance of India's classical performing arts covers the theoretical aspects, musical instruments, the main schools of classical dance, and drama. Besides the basic research described, the total project produced a set of 300 slides with annotated listing, picturing the…

Measuring the Multiplication of Spent Fuel Assemblies – It’s easier than you think!

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

Tobin, Stephen Joseph

This is a set of eight slides which advertise how easy it can be to measure the multiplication of a spent fuel assembly. A robust (fission chambers), rapid (under 15 minutes), direct (multiplication is measured, not photons from fission fragments) measurement of multiplication is possible.

Effect of Teaching a Conceptual Hierarchy on Concept Classification Performance.

ERIC Educational Resources Information Center

Wilcox, Wayne C.; And Others

1981-01-01

In the research study described, 80 subjects in one control and four treatment groups viewed sets of slides on types of sailboats. Results indicate that making apparent the hierarchical relationships among concepts of a conceptual hierarchy enhances learner performance in classifying unencountered instances of those concepts. Thirty-eight…

Susceptibility analysis for slides and rockfall: an example from the Northern Calcareous Alps (Vorarlberg, Austria)

NASA Astrophysics Data System (ADS)

Ruff, Michael; Rohn, Joachim

2008-07-01

In this paper a tool for semi-quantitative susceptibility assessment at a regional scale is presented which is applicable at areas with complex geological setting. At a study area within the Northern Calcareous Alps geotechnical mappings were implemented into a Geographical Information System and analysed as grid data with a cell size of 25 m. The susceptibility to sliding and falling processes was considered according to five classes (very low, low, medium, high, very high). Susceptibility to sliding was analysed using an index method. The layers of lithology, bedding conditions, tectonic faults, slope angle, slope aspect, vegetation and erosion were combined iteratively. Dropout zones of rockfall material were determined with help of a Digital Elevation Model. The movement of rolling rock samples was modelled by a cost analysis of all potential rockfall trajectories. These trajectories were also divided into five susceptibility classes. The susceptibility maps are presented in a general way to be used by communities and spatial planners. Conflict areas of susceptibility and landuse were located and can be presented destinctively.

Parametric output-only identification of time-varying structures using a kernel recursive extended least squares TARMA approach

NASA Astrophysics Data System (ADS)

Ma, Zhi-Sai; Liu, Li; Zhou, Si-Da; Yu, Lei; Naets, Frank; Heylen, Ward; Desmet, Wim

2018-01-01

The problem of parametric output-only identification of time-varying structures in a recursive manner is considered. A kernelized time-dependent autoregressive moving average (TARMA) model is proposed by expanding the time-varying model parameters onto the basis set of kernel functions in a reproducing kernel Hilbert space. An exponentially weighted kernel recursive extended least squares TARMA identification scheme is proposed, and a sliding-window technique is subsequently applied to fix the computational complexity for each consecutive update, allowing the method to operate online in time-varying environments. The proposed sliding-window exponentially weighted kernel recursive extended least squares TARMA method is employed for the identification of a laboratory time-varying structure consisting of a simply supported beam and a moving mass sliding on it. The proposed method is comparatively assessed against an existing recursive pseudo-linear regression TARMA method via Monte Carlo experiments and shown to be capable of accurately tracking the time-varying dynamics. Furthermore, the comparisons demonstrate the superior achievable accuracy, lower computational complexity and enhanced online identification capability of the proposed kernel recursive extended least squares TARMA approach.

Design of isolated buildings with S-FBI system subjected to near-fault earthquakes using NSGA-II algorithm

NASA Astrophysics Data System (ADS)

Ozbulut, O. E.; Silwal, B.

2014-04-01

This study investigates the optimum design parameters of a superelastic friction base isolator (S-FBI) system through a multi-objective genetic algorithm and performance-based evaluation approach. The S-FBI system consists of a flat steel- PTFE sliding bearing and a superelastic NiTi shape memory alloy (SMA) device. Sliding bearing limits the transfer of shear across the isolation interface and provides damping from sliding friction. SMA device provides restoring force capability to the isolation system together with additional damping characteristics. A three-story building is modeled with S-FBI isolation system. Multiple-objective numerical optimization that simultaneously minimizes isolation-level displacements and superstructure response is carried out with a genetic algorithm (GA) in order to optimize S-FBI system. Nonlinear time history analyses of the building with S-FBI system are performed. A set of 20 near-field ground motion records are used in numerical simulations. Results show that S-FBI system successfully control response of the buildings against near-fault earthquakes without sacrificing in isolation efficacy and producing large isolation-level deformations.

A comparison of digitized frozen section and smear preparations for intraoperative neurotelepathology.

PubMed

Gould, Peter V; Saikali, Stephan

2012-01-01

Intraoperative consultations in neuropathology are often assessed by smear preparations rather than by frozen sections. Both techniques are standard practice for light microscopic examination on site, but there is little data comparing these techniques in a telepathology setting. Thirty cases of brain tumours submitted for intraoperative consultation at our institution between July and December 2010 were identified in which both frozen section and tissue smear preparations were available for digitization at 20× magnification. Slides were digitized using a Hamamatsu Nanozoomer 2.0 HT whole slide scanner, and resulting digital images were visualized at 1680 × 1050 pixel resolution with NDP. view software. The original intraoperative diagnosis was concordant with the sign out diagnosis in 29/30 cases; one tumeur was initially interpreted as a high grade glioma but proved to be a lymphoma at sign out. Digitized frozen section slides were sufficient for diagnosis at 10× magnification in 27/30 cases. Digitized tissue smears were sufficient for diagnosis at 10× magnification in 28/30 cases. In two cases tumour was present on the tissue smear but not the frozen section (one case of recurrent astrocytoma, one case of meningeal carcinomatosis). In one case of lymphoma, tumour was present on frozen section only. These discrepancies were attributed to tissue sampling rather than image quality. Examination of digitized slides at higher magnfication (20×) permitted confirmation of mitoses and Rosenthal fibers on tissue smear preparations, but did not change the primary diagnosis. Intra-slide variations in tissue thickness on smear preparations led to variable loss of focus in digitized images, but did not affect image quality in thinner areas of the smear or impede diagnosis. Digitized tissue smears are suitable for intraoperative neurotelepathology and provide comparable information to digitized frozen sections at medium power magnification.

ALK status testing in non-small-cell lung carcinoma by FISH on ThinPrep slides with cytology material.

PubMed

Minca, Eugen C; Lanigan, Christopher P; Reynolds, Jordan P; Wang, Zhen; Ma, Patrick C; Cicenia, Joseph; Almeida, Francisco A; Pennell, Nathan A; Tubbs, Raymond R

2014-04-01

Oncogenic anaplastic lymphoma kinase (ALK) gene rearrangements in non-small-cell lung carcinomas (NSCLC) provide the basis for targeted therapy with crizotinib and other specific ALK inhibitors. Treatment eligibility is conventionally determined by the Food and Drug Administration-approved companion diagnostic fluorescence in situ hybridization (FISH) assay on paraffin-embedded tissue (PET). On limited samples such as fine needle aspiration-derived cytoblocks, FISH for ALK is often uninformative. FISH performed on liquid-based ThinPrep slides (ThinPrep-FISH) may represent a robust alternative. Two hundred thirty cytology samples from 217 patients with advanced NSCLC, including a consecutive series of 179 specimens, were used to generate matched ThinPrep slides and paraffin cytoblocks. The same ThinPrep slides used for cytologic diagnosis were assessed by standard ALK break-apart two-color probe FISH, after etching of tumor areas. Ultrasensitive ALK immunohistochemistry (IHC) on corresponding cytoblocks [D5F3 antibody, OptiView signal amplification] served as the reference data set. ThinPrep-FISH ALK signals were robust in 228 of 230 cases and not compromised by nuclear truncation inherent in paraffin-embedded tissue-FISH; only two samples displayed no signals. Nine of 178 informative cases (5%) in the consecutive series and 18 of 228 informative cases (7.8%) overall were ALK rearranged by ThinPrep-FISH. In 154 informative matched ThinPrep-FISH and cytoblock-IHC samples, 152 were concordant (10, 6.5% ALK status positive; 142, 92.2% ALK status negative), and two (1.3%) were ThinPrep-FISH positive but IHC negative (sensitivity 100%, specificity 98.6%, overall agreement 98.7%). Detection of ALK gene rearrangements in liquid cytology ThinPrep slides derived from patients with NSCLC can be confidently used for clinical ALK molecular testing.

Energy Consumption of Actively Beating Flagella

NASA Astrophysics Data System (ADS)

Chen, Daniel; Nicastro, Daniela; Dogic, Zvonimir

2012-02-01

Motile cilia and flagella are important for propelling cells or driving fluid over tissues. The microtubule-based core in these organelles, the axoneme, has a nearly universal ``9+2'' arrangement of 9 outer doublet microtubules assembled around two singlet microtubules in the center. Thousands of molecular motor proteins are attached to the doublets and walk on neighboring outer doublets. The motors convert the chemical energy of ATP hydrolysis into sliding motion between adjacent doublet microtubules, resulting in precisely regulated oscillatory beating. Using demembranated sea urchin sperm flagella as an experimental platform, we simultaneously monitor the axoneme's consumption of ATP and its beating dynamics while key parameters, such as solution viscosity and ATP concentration, are varied. Insights into motor cooperativity during beating and energetic consequences of hydrodynamic interactions will be presented.

A triboelectric wind turbine for small-scale energy harvesting

NASA Astrophysics Data System (ADS)

Perez, Matthias; Boisseau, Sebastien; Geisler, Matthias; Despesse, Ghislain; Reboud, Jean Luc

2016-11-01

This paper deals with a rotational energy harvester including a Horizontal Axis Wind Turbine (HAWT), a cylindrical stator covered by several electrodes, and thin Teflon dielectric membranes hung on the rotor. The sliding contact of the Teflon membranes on the stator provides simultaneously large capacitance variations and a polarization source for the electrostatic converter by exploiting triboelectric phenomena. 1μW has been harvested at 4m/s; 130μW at 10m/s and 550μW at 20m/s with a 40mmØ device. In order to validate the energy harvesting chain, the airflow energy harvester has been connected to a power management circuit implementing Synchronous Electric Charge Extraction (SECE) to supply a wireless sensor node with temperature and acceleration measurements, transmitted to a computer at 868MHz.

Sliding window prior data assisted compressed sensing for MRI tracking of lung tumors.

PubMed

Yip, Eugene; Yun, Jihyun; Wachowicz, Keith; Gabos, Zsolt; Rathee, Satyapal; Fallone, B G

2017-01-01

Hybrid magnetic resonance imaging and radiation therapy devices are capable of imaging in real-time to track intrafractional lung tumor motion during radiotherapy. Highly accelerated magnetic resonance (MR) imaging methods can potentially reduce system delay time and/or improves imaging spatial resolution, and provide flexibility in imaging parameters. Prior Data Assisted Compressed Sensing (PDACS) has previously been proposed as an acceleration method that combines the advantages of 2D compressed sensing and the KEYHOLE view-sharing technique. However, as PDACS relies on prior data acquired at the beginning of a dynamic imaging sequence, decline in image quality occurs for longer duration scans due to drifts in MR signal. Novel sliding window-based techniques for refreshing prior data are proposed as a solution to this problem. MR acceleration is performed by retrospective removal of data from the fully sampled sets. Six patients with lung tumors are scanned with a clinical 3 T MRI using a balanced steady-state free precession (bSSFP) sequence for 3 min at approximately 4 frames per second, for a total of 650 dynamics. A series of distinct pseudo-random patterns of partial k-space acquisition is generated such that, when combined with other dynamics within a sliding window of 100 dynamics, covers the entire k-space. The prior data in the sliding window are continuously refreshed to reduce the impact of MR signal drifts. We intended to demonstrate two different ways to utilize the sliding window data: a simple averaging method and a navigator-based method. These two sliding window methods are quantitatively compared against the original PDACS method using three metrics: artifact power, centroid displacement error, and Dice's coefficient. The study is repeated with pseudo 0.5 T images by adding complex, normally distributed noise with a standard deviation that reduces image SNR, relative to original 3 T images, by a factor of 6. Without sliding window implemented, PDACS-reconstructed dynamic datasets showed progressive increases in image artifact power as the 3 min scan progresses. With sliding windows implemented, this increase in artifact power is eliminated. Near the end of a 3 min scan at 3 T SNR and 5× acceleration, implementation of an averaging (navigator) sliding window method improves our metrics by the following ways: artifact power decreases from 0.065 without sliding window to 0.030 (0.031), centroid error decreases from 2.64 to 1.41 mm (1.28 mm), and Dice coefficient agreement increases from 0.860 to 0.912 (0.915). At pseudo 0.5 T SNR, the improvements in metrics are as follows: artifact power decreases from 0.110 without sliding window to 0.0897 (0.0985), centroid error decreases from 2.92 mm to 1.36 mm (1.32 mm), and Dice coefficient agreements increases from 0.851 to 0.894 (0.896). In this work we demonstrated the negative impact of slow changes in MR signal for longer duration PDACS dynamic scans, namely increases in image artifact power and reductions of tumor tracking accuracy. We have also demonstrated sliding window implementations (i.e., refreshing of prior data) of PDACS are effective solutions to this problem at both 3 T and simulated 0.5 T bSSFP images. © 2016 American Association of Physicists in Medicine.

[The reaction to viewing slides on tropical medicine. Evaluation study].

PubMed

Gateff, C; Merouze, F; Gaud, R; Bourrel, P

1985-01-01

A series of slides on health priorities in Africa was shown to an audience of 123 people, of which 19 were not medical specialists. The authors of this experiment wanted to verify that the objectives set by the producers were met. The study, conducted in the form of a questionnaire, asked the people questioned to give their opinion on the objectives, the kind of public aimed at, the standard of the various subjects covered and the usefulness and cost-efficiency ratio of the type of audio-visual equipment used. Although the analysis of collected data reveals certain discrepancies as to the professional status of those questioned, the vast majority of participants considered this documentary support to be extremely worthwhile.

Reliable Detection and Smart Deletion of Malassez Counting Chamber Grid in Microscopic White Light Images for Microbiological Applications.

PubMed

Denimal, Emmanuel; Marin, Ambroise; Guyot, Stéphane; Journaux, Ludovic; Molin, Paul

2015-08-01

In biology, hemocytometers such as Malassez slides are widely used and are effective tools for counting cells manually. In a previous work, a robust algorithm was developed for grid extraction in Malassez slide images. This algorithm was evaluated on a set of 135 images and grids were accurately detected in most cases, but there remained failures for the most difficult images. In this work, we present an optimization of this algorithm that allows for 100% grid detection and a 25% improvement in grid positioning accuracy. These improvements make the algorithm fully reliable for grid detection. This optimization also allows complete erasing of the grid without altering the cells, which eases their segmentation.

Scanning microarray slides.

PubMed

Ares, Manuel

2014-02-01

Here we describe some practical concerns surrounding the scanning of microarray slides that have been hybridized with fluorescent dyes. We use a laser scanner that has two lasers, each set to excite a different fluor, and separate detectors to capture emission from each fluor. The laser passes over an address (position on the scanned surface) and the detectors capture photons emitted from each address. Two superimposed image files are written that carry intensities for each channel for each pixel of the image scan. These are the raw data. Image analysis software is used to identify and summarize the intensities of the pixels that make up each spot. After comparison to background pixels, the processed intensity levels representing the gene expression measurements are associated with the identity of each spot.

Impulse position control algorithms for nonlinear systems

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

Sesekin, A. N., E-mail: sesekin@list.ru; Institute of Mathematics and Mechanics, Ural Division of Russian Academy of Sciences, 16 S. Kovalevskaya, Ekaterinburg, 620990; Nepp, A. N., E-mail: anepp@urfu.ru

2015-11-30

The article is devoted to the formalization and description of impulse-sliding regime in nonlinear dynamical systems that arise in the application of impulse position controls of a special kind. The concept of trajectory impulse-sliding regime formalized as some limiting network element Euler polygons generated by a discrete approximation of the impulse position control This paper differs from the previously published papers in that it uses a definition of solutions of systems with impulse controls, it based on the closure of the set of smooth solutions in the space of functions of bounded variation. The need for the study of suchmore » regimes is the fact that they often arise when parry disturbances acting on technical or economic control system.« less

Printing Proteins as Microarrays for High-Throughput Function Determination

NASA Astrophysics Data System (ADS)

MacBeath, Gavin; Schreiber, Stuart L.

2000-09-01

Systematic efforts are currently under way to construct defined sets of cloned genes for high-throughput expression and purification of recombinant proteins. To facilitate subsequent studies of protein function, we have developed miniaturized assays that accommodate extremely low sample volumes and enable the rapid, simultaneous processing of thousands of proteins. A high-precision robot designed to manufacture complementary DNA microarrays was used to spot proteins onto chemically derivatized glass slides at extremely high spatial densities. The proteins attached covalently to the slide surface yet retained their ability to interact specifically with other proteins, or with small molecules, in solution. Three applications for protein microarrays were demonstrated: screening for protein-protein interactions, identifying the substrates of protein kinases, and identifying the protein targets of small molecules.

Meltwater Origin of the 2005 Mount Steller Landslide Confirmed by Analysis of Global Fiducials Program Imagery

NASA Astrophysics Data System (ADS)

Molnia, B. F.; Angeli, K.

2012-12-01

Alaska's Mt. Steller, a 3,236 m Chugach Mountains peak, is one of the target areas of the Bering Glacier Global Fiducials Program (GFP) site. On September 14, 2005, a large mass of rock, glacier ice, and snow, with a volume of ~50 million cubic meters, fell from just below Mt. Steller's south-facing summit and landed on the surface of a tributary to Bering Glacier, nearly 2,500 m below. The slide, which extended ~8 km down-glacier, was actually an ice-rock avalanche. The impact generated a seismic signal recorded with a magnitude of up to 5.2. Oblique aerial photography of the mountain, the head scarp, and the slide mass was collected for the U.S. Geological Survey's Alaska Volcano Observatory (AVO) on September 15, 2005. The photography delineated the morphology of the failed south-facing slope of the mountain and showed details of the sheared, near-summit hanging glacier and snow mass. Based on the photography, the AVO calculated the slide volume and length. Several weeks later, the AVO provided the first author with digital copies of the September 15 photography. These images were enhanced and examined in order to determine properties of the slide and to evaluate if the cause of the event could be determined. A number of features observed led to the conclusion that meltwater was probably responsible for destabilizing the glacier ice-bedrock contact and triggering the landslide. Specifically, a 10-15 m diameter englacial stream channel was seen in the truncated glacier ice that comprised the east wall of the landslide scarp and a water-polished channel opening was noted on the west wall scarp. Additionally, several depressions were noted that might have temporarily stored water. To confirm these observations, new cloud-free GFP imagery was obtained on October 24 and 28, 2005. Analysis of both sets of imagery documented that: (1) more than a month after the event, meltwater was exiting the east wall scarp channel and flowing down the face of the mountain; (2) the roof of the west wall channel tunnel had collapsed and its path could be discerned in the remaining ice and snow; (3) several near-summit depressions remained that suggested liquid water may have existed and been temporarily stored; (4) the surface on which the slide occurred had a slope that was >50 degrees; (5) the slide mass had many unique components suggesting a complex series of related failures; and (6) there was an absence of large rock bodies in the slide debris, suggesting that much of the failed material may have previously been fractured by freeze-thaw processes. The timely collection of GFP imagery confirmed the continued presence of meltwater near the point of origin of this slide. Coupled with the September 15 oblique photography, interpretation of these images suggests that a large volume of water had recently been flowing on Steller's east summit ridge and that the water might have had a role in triggering the landslide. The presence of a large volume of water close to the summit raises questions about climate change and its role in the future generation of high elevation landslides. Although Mt. Steller is tens of kilometers from the closest human infrastructure, there are numerous other settings around the world where mountains with similar elevations, hanging glaciers, and sun-facing orientations are in close proximity to human infrastructure.

Rapid preparation of lecture slides.

PubMed

Persson, A V; Frusha, J D; Chevalier, R J

1985-02-01

When lecture slides must be prepared at a moment's notice, these methods of rapid preparation will allow you to create good quality slides. Although rush jobs are usually associated with higher costs, using these methods will keep the price per slide to a minimum. An investment must be made for the initial equipment, but the cost per slide is much less than that of slides produced by the standard methods. Type produced by typewriters or computer printers is adequate for most slides, but better slides can be produced with KroyType or Letraset letters. The KL film is preferred for reverse slides of text or line drawings, and the RPC film for production of radiographic slides. If an X-omat developer is not available, Polaroid film is a good alternative for rapid production of slides. The KL reverse slide projects best and can be colored, but RPC film produces a good positive slide of typed material. We have also photographed from a computer terminal screen using the KL film to make positive slides, the Polaroid continuous tone film for reverse slides, and Polaroid color film for color slides of material composed on a computer terminal with multicolor and graphics capabilities.

Image Transform Based on the Distribution of Representative Colors for Color Deficient

NASA Astrophysics Data System (ADS)

Ohata, Fukashi; Kudo, Hiroaki; Matsumoto, Tetsuya; Takeuchi, Yoshinori; Ohnishi, Noboru

This paper proposes the method to convert digital image containing distinguishing difficulty sets of colors into the image with high visibility. We set up four criteria, automatically processing by a computer, retaining continuity in color space, not making images into lower visible for people with normal color vision, and not making images not originally having distinguishing difficulty sets of colors into lower visible. We conducted the psychological experiment. We obtained the result that the visibility of a converted image had been improved at 60% for 40 images, and we confirmed the main criterion of the continuity in color space was kept.

Use of a magnetic force exciter to vibrate a piezocomposite generating element in a small-scale windmill

NASA Astrophysics Data System (ADS)

Truyen Luong, Hung; Goo, Nam Seo

2012-02-01

A piezocomposite generating element (PCGE) can be used to convert ambient vibrations into electrical energy that can be stored and used to power other devices. This paper introduces a design of a magnetic force exciter for a small-scale windmill that vibrates a PCGE to convert wind energy into electrical energy. A small-scale windmill was designed to be sensitive to low-speed wind in urban regions for the purpose of collecting wind energy. The magnetic force exciter consists of exciting magnets attached to the device’s input rotor and a secondary magnet fixed at the tip of the PCGE. The PCGE is fixed to a clamp that can be adjusted to slide on the windmill’s frame in order to change the gap between exciting and secondary magnets. Under an applied wind force, the input rotor rotates to create a magnetic force interaction that excites the PCGE. The deformation of the PCGE enables it to generate electric power. Experiments were performed with different numbers of exciting magnets and different gaps between the exciting and secondary magnets to determine the optimal configuration for generating the peak voltage and harvesting the maximum wind energy for the same range of wind speeds. In a battery-charging test, the charging time for a 40 mA h battery was approximately 3 h for natural wind in an urban region. The experimental results show that the prototype can harvest energy in urban regions with low wind speeds and convert the wasted wind energy into electricity for city use.

An Easy Method for Preparing Presentation Slides.

ERIC Educational Resources Information Center

Wright, Norman A.; Blevins, Dennis D.

1984-01-01

Describes a simplified method of preparing 35mm projection slides with a minimum of equipment and expertise. The quality of these slides compares favorably to professionally produced diazo slides. Twenty-five slides can easily be prepared in less than three hours. Material cost per slide is comparable to professional color slide processing. (JN)

Solar power generation system for reducing leakage current

NASA Astrophysics Data System (ADS)

Wu, Jinn-Chang; Jou, Hurng-Liahng; Hung, Chih-Yi

2018-04-01

This paper proposes a transformer-less multi-level solar power generation system. This solar power generation system is composed of a solar cell array, a boost power converter, an isolation switch set and a full-bridge inverter. A unipolar pulse-width modulation (PWM) strategy is used in the full-bridge inverter to attenuate the output ripple current. Circuit isolation is accomplished by integrating the isolation switch set between the solar cell array and the utility, to suppress the leakage current. The isolation switch set also determines the DC bus voltage for the full-bridge inverter connecting to the solar cell array or the output of the boost power converter. Accordingly, the proposed transformer-less multi-level solar power generation system generates a five-level voltage, and the partial power of the solar cell array is also converted to AC power using only the full-bridge inverter, so the power efficiency is increased. A prototype is developed to validate the performance of the proposed transformer-less multi-level solar power generation system.

Portable convertible blast effects shield

DOEpatents

Pastrnak, John W.; Hollaway, Rocky; Henning, Carl D.; Deteresa, Steve; Grundler, Walter; Hagler,; Lisle B.; Kokko, Edwin; Switzer, Vernon A

2010-10-26

A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more telescoping cylindrical rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration, such as by click locks.

Portable convertible blast effects shield

DOEpatents

Pastrnak, John W [Livermore, CA; Hollaway, Rocky [Modesto, CA; Henning, Carl D [Livermore, CA; Deteresa, Steve [Livermore, CA; Grundler, Walter [Hayward, CA; Hagler, Lisle B [Berkeley, CA; Kokko, Edwin [Dublin, CA; Switzer, Vernon A [Livermore, CA

2007-05-22

A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more telescoping cylindrical rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration, such as by click locks.

Cost-effectiveness analysis of fixation options for intertrochanteric hip fractures.

PubMed

Swart, Eric; Makhni, Eric C; Macaulay, William; Rosenwasser, Melvin P; Bozic, Kevin J

2014-10-01

Intertrochanteric hip fractures are a major source of morbidity and financial burden, accounting for 7% of osteoporotic fractures and costing nearly $6 billion annually in the United States. Traditionally, "stable" fracture patterns have been treated with an extramedullary sliding hip screw whereas "unstable" patterns have been treated with the more expensive intramedullary nail. The purpose of this study was to identify parameters to guide cost-effective implant choices with use of decision-analysis techniques to model these common clinical scenarios. An expected-value decision-analysis model was constructed to estimate the total costs and health utility based on the choice of a sliding hip screw or an intramedullary nail for fixation of an intertrochanteric hip fracture. Values for critical parameters, such as fixation failure rate, were derived from the literature. Three scenarios were evaluated: (1) a clearly stable fracture (AO type 31-A1), (2) a clearly unstable fracture (A3), or (3) a fracture with questionable stability (A2). Sensitivity analysis was performed to test the validity of the model. The fixation failure rate and implant cost were the most important factors in determining implant choice. When the incremental cost for the intramedullary nail was set at the median value ($1200), intramedullary nailing had an incremental cost-effectiveness ratio of $50,000/quality-adjusted life year when the incremental failure rate of sliding hip screws was 1.9%. When the incremental failure rate of sliding hip screws was >5.0%, intramedullary nails dominated with lower cost and better health outcomes. The sliding hip screw was always more cost-effective for A1 fractures, and the intramedullary nail always dominated for A3 fractures. As for A2 fractures, the sliding hip screw was cost-effective in 70% of the cases, although this was highly sensitive to the failure rate. Sliding hip screw fixation is likely more cost-effective for stable intertrochanteric fractures (A1) or those with questionable stability (A2), whereas intramedullary nail fixation is more cost-effective for reverse obliquity fractures (A3). These conclusions are highly sensitive to the fixation failure rate, which was the major influence on the model results. Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.

Size Constraints on Late Miocene to Pliocene Submarine Slope Failures along the Colombian Caribbean Subduction Margin as a Basis for Assessing Circum-Caribbean Impact of Future Tsunami Events

NASA Astrophysics Data System (ADS)

Leslie, S.; Mann, P.

2015-12-01

The Colombian Caribbean margin provides an ideal setting for the formation of large mass transport deposits (MTDs): 1) the Caribbean Plate is slowly subducting at rates of 20 mm/yr with infrequent large thrust earthquakes and a complete lack of subduction events in the 400-year-long historical record; 2) the margin is a broad zone of active faults including a ~50 km-wide accretionary prism and strike-slip faults landward of the prism; 3) the active margin is draped by the Magdalena delta and submarine fan fed by the Magdalena River, the 26th largest in the world; and 4) the margin is over-steepened to slopes of up to 7° from the combination of tectonic activity and rapid rates of deltaic progradation. Using seismic data we have identified three late Miocene-Pliocene MTDs, the largest of which is between 4500 and 6000 km3, comparable in size to the well-studied Storegga slide of Norway. The tsunamigenic potential of future, analog MTD events are modeled using GeoWave tsunami modeling software. The largest and youngest of these MTDs, the Santa Marta slide, is used as an analog to infer the location and input parameters for the tsunami model. The event is modeled as a translational slide ~46 km long and ~37 km wide with the center of the slide located ~57 km W/NW from the mouth of the present day Magdalena River in water depths of 1500 m. The volume for the initial failure is conservatively estimated at ~680 km3 of material. The resulting tsunami wave from such an event has an initial maximum trough amplitude of -65.8 m and a peak amplitude of 19.2 m. The impact of such a tsunami would include: 1) Kingston, Jamaica (population 938K), tsunami height 7.5 m, peak arrival at 60 min.; 2) Santo Domingo, Dominican Republic (population 965K, height 6 m, peak arrival at 80 min.); and 3) Cartagena, Colombia (population 845K, height 21 m, peak arrival at 34 min.). A number of parameters to the model are varied to analyze sensitivity of modeling results to changes in slide depth, angle of failure, slide volume, and slide density.

Thermionic converter

DOEpatents

Fitzpatrick, Gary O.

1987-05-19

A thermionic converter (10) is set forth which includes an envelope (12) having an electron collector structure (22) attached adjacent to a wall (16). An electron emitter structure (24) is positioned adjacent the collector structure (22) and spaced apart from opposite wall (14). The emitter (24) and collector (22) structures are in a common chamber (20). The emitter structure (24) is heated substantially only by thermal radiation. Very small interelectrode gaps (28) can be maintained utilizing the thermionic converter (10) whereby increased efficiency results.

Therapeutic Influence as a Function of Therapist Attire and the Seating Arrangement in an Initial Interview.

ERIC Educational Resources Information Center

Gass, Carlton S.

1984-01-01

Investigated the impact of therapist attire and seating arrangement on observers' perceptions of a therapist's attractiveness, expertise, and trustworthiness. Undergraduates (N=233) listened to an audiotaped interview while viewing a slide presentation. The casual attire/no desk setting elicited the highest attraction ratings, mediated by the…

Behavioral Objectives, Science Processes, and Learning from Inquiry-Oriented Instructional Materials.

ERIC Educational Resources Information Center

Anderson, Elaine J.; And Others

Investigated was the effect of systematically combined high and low level cognitive objectives upon the acquisition of science learning. An instructional unit based on a Biological Sciences Curriculum Study (BSCS) Inquiry Slide Set (structure and function, control of blood sugar, a homeostatic mechanism) was chosen because it included stimuli for…

A Resource Guide on Indian Arts and Crafts for Elementary and Secondary Teachers.

ERIC Educational Resources Information Center

Fagot, Madeleine

American Indian arts and crafts reference materials (published 1923-1973) are listed in this annotated resource guide for elementary and secondary school teachers. Approximately 260 listings are given for: books, films and filmstrips, maps and charts, picture sets, magazines, bibliographies and indexes, slide kits, transparencies, distributor's…

Eyewitness Evidence: A Trainer's Manual for Law Enforcement. NIJ Special Report.

ERIC Educational Resources Information Center

Department of Justice, Washington, DC. National Inst. of Justice.

This training manual and guide (which consists of a set of 142 slides) were created by experienced law enforcement investigators, prosecutors, defense lawyers, and psychology researchers and are intended to be used by law enforcement trainers to teach law enforcement personnel how to collect accurate and reliable eyewitness evidence. The manual…

Planetary data system requirements: Multi-mission radio science requirements for the 1978 to 1988 era

NASA Technical Reports Server (NTRS)

Howard, H. T. (Editor)

1979-01-01

The functional and performance requirements for support of multimission radio science are established. The classes of radio science investigation are described and the needed data is discussed. This document is for a sliding ten year period and will be iterated as the mission set evolves.

The Winogradsky Column and Biofilms: Models for Teaching Nutrient Cycling and Succession in an Ecosystem.

ERIC Educational Resources Information Center

Anderson, Delia Castro; Hairston, Rosalina V.

1999-01-01

Presents protocols for setting up a Winogradsky column and biofilm slides, interpreting the chemical transformations that occur in the column as a result of color changes in the soil, identifying common microorganisms, and determining the microbial composition of the column over specified intervals of time. (WRM)

Easy Demonstration of the Poisson Spot

ERIC Educational Resources Information Center

Gluck, Paul

2010-01-01

Many physics teachers have a set of slides of single, double and multiple slits to show their students the phenomena of interference and diffraction. Thomas Young's historic experiments with double slits were indeed a milestone in proving the wave nature of light. But another experiment, namely the Poisson spot, was also important historically and…

Trickling Filters. Instructor's Guide. Biological Treatment Process Control.

ERIC Educational Resources Information Center

Richwine, Reynold D.

This instructor's guide contains materials needed for teaching a two-lesson unit on trickling filters. These materials include: (1) an overview of the two lessons; (2) lesson plans; (3) lecture outline (keyed to a set of slides accompanying the unit); (4) overhead transparency masters; (5) student worksheet (with answers); and (6) two copies of a…

The Interaction of Color Realism and Pictorial Recall Memory.

ERIC Educational Resources Information Center

Berry, Louis H.

This study investigated the interaction of variations in color realism on pictorial recall memory in order to better understand the effects of variations in color realism, and to draw comparisons between visual recall memory and visual recognition memory in terms of color information processing. Stimulus materials used were three sets of slides,…

Un document authentique pedagogique: le constat amiable (An Authentic Pedagogical Document: The Accident Report)

ERIC Educational Resources Information Center

Davoine, Jean-Pierre

1978-01-01

A discussion of the use of an accident report form, especially for practice in past tense usage. A lesson plan is outlined as follows: introduction using slides, a question-answer session between two sets of students and the actual writing of the report. (Text is in French.) (AMH)

42 CFR 493.945 - Cytology; gynecologic examinations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... dysplasia/CIN-2 and severe dysplasia/carcinoma in-situ/CIN-3. (2) Squamous cell carcinoma. (3... gynecologic examinations (Pap smears) in cytology, a program must provide test sets composed of 10- and 20..., provided the slides have been retained by the laboratory for the required period specified in §§ 493.1105(a...

Novel chromatin texture features for the classification of pap smears

NASA Astrophysics Data System (ADS)

Bejnordi, Babak E.; Moshavegh, Ramin; Sujathan, K.; Malm, Patrik; Bengtsson, Ewert; Mehnert, Andrew

2013-03-01

This paper presents a set of novel structural texture features for quantifying nuclear chromatin patterns in cells on a conventional Pap smear. The features are derived from an initial segmentation of the chromatin into bloblike texture primitives. The results of a comprehensive feature selection experiment, including the set of proposed structural texture features and a range of different cytology features drawn from the literature, show that two of the four top ranking features are structural texture features. They also show that a combination of structural and conventional features yields a classification performance of 0.954±0.019 (AUC±SE) for the discrimination of normal (NILM) and abnormal (LSIL and HSIL) slides. The results of a second classification experiment, using only normal-appearing cells from both normal and abnormal slides, demonstrates that a single structural texture feature measuring chromatin margination yields a classification performance of 0.815±0.019. Overall the results demonstrate the efficacy of the proposed structural approach and that it is possible to detect malignancy associated changes (MACs) in Papanicoloau stain.

An adaptable navigation strategy for Virtual Microscopy from mobile platforms.

PubMed

Corredor, Germán; Romero, Eduardo; Iregui, Marcela

2015-04-01

Real integration of Virtual Microscopy with the pathologist service workflow requires the design of adaptable strategies for any hospital service to interact with a set of Whole Slide Images. Nowadays, mobile devices have the actual potential of supporting an online pervasive network of specialists working together. However, such devices are still very limited. This article introduces a novel highly adaptable strategy for streaming and visualizing WSI from mobile devices. The presented approach effectively exploits and extends the granularity of the JPEG2000 standard and integrates it with different strategies to achieve a lossless, loosely-coupled, decoder and platform independent implementation, adaptable to any interaction model. The performance was evaluated by two expert pathologists interacting with a set of 20 virtual slides. The method efficiently uses the available device resources: the memory usage did not exceed a 7% of the device capacity while the decoding times were smaller than the 200 ms per Region of Interest, i.e., a window of 256×256 pixels. This model is easily adaptable to other medical imaging scenarios. Copyright © 2015 Elsevier Inc. All rights reserved.

Pharmacogenetic studies of antidepressant response: how far from the clinic?

PubMed

Perlis, Roy H

2007-03-01

Because the US FDA has begun to focus on disclosure of pharmacogenetic testing results in applications for new drug approval and review of existing drugs (see, eg, http://www.fda.gov/OHRMS/DOCKETS/AC/05/slides/2005-4194S1_Slide-Index.htm), the application of such testing in a clinical setting is likely to increase substantially. Instead of small cohorts of patients, potentially nearly every participant in the large pivotal trials required for drug approval could help inform the future application of that drug. Psychiatry as a whole, and antidepressant prescribing ni particular, stands to benefit in the near term from the identification of newer treatment targets that may overcome some of the limitations of current therapeutics. On the other hand, despite the excitement about the rapid pace of development in psychiatric pharmacogenetics, a number of key issues remain to be addressed before these discoveries are applied in a clinical setting. Close coordination will be required between those who study treatment efficacy and effectiveness and those who study genetic variation in populations to ensure that studies yield results that have scientific importance and clinical importance as well.

Alpha2-Adrenergic Receptors and Breast Tumor Stroma: A Novel Pathway Driving Breast Cancer Growth and Metastasis

DTIC Science & Technology

2015-10-01

sectioned into 5-micron sections. Three serial sections were mounted onto each slide and stained using hematoxylin and eosin (H&E). Five sets of... serial sections were taken from each lung, 100 µm distance between each set. This spacing allows surveillance of metastatic lesions throughout the lung...functions that promote tumor growth may be altered by DEX treatment. For example, IFN- is associated with effector function of natural killer cells

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

Gluskin, Efim; Trakhtenberg, Emil; Xu, Joseph Z.

A method and apparatus for implementing dynamic compensation of magnetic forces for undulators are provided. An undulator includes a respective set of magnet arrays, each attached to a strongback, and placed on horizontal slides and positioned parallel relative to each other with a predetermined gap. Magnetic forces are compensated by a set of compensation springs placed along the strongback. The compensation springs are conical springs having exponential-force characteristics that substantially match undulator magnetic forces independently of the predetermined gap. The conical springs are positioned along the length of the magnets.

Unified System Of Data On Materials And Processes

NASA Technical Reports Server (NTRS)

Key, Carlo F.

1989-01-01

Wide-ranging sets of data for aerospace industry described. Document describes Materials and Processes Technical Information System (MAPTIS), computerized set of integrated data bases for use by NASA and aerospace industry. Stores information in standard format for fast retrieval in searches and surveys of data. Helps engineers select materials and verify their properties. Promotes standardized nomenclature as well as standarized tests and presentation of data. Format of document of photographic projection slides used in lectures. Presents examples of reports from various data bases.

Tools for the IDL widget set within the X-windows environment

NASA Technical Reports Server (NTRS)

Turgeon, B.; Aston, A.

1992-01-01

New tools using the IDL widget set are presented. In particular, a utility allowing the easy creation and update of slide presentations, XSlideManager, is explained in detail and examples of its application are shown. In addition to XSlideManager, other mini-utilities are discussed. These various pieces of software follow the philosophy of the X-Windows distribution system and are made available to anyone within the Internet network. Acquisition procedures through anonymous ftp are clearly explained.

Baseball and softball sliding injuries: incidence and correlates during one high school league varsity season.

PubMed

Stovak, Mark; Parikh, Amit; Harvey, Anne T

2012-11-01

To estimate injury rates associated with sliding in high school baseball and softball. Prospective cohort study. Community high school athletic events. Ten high school varsity baseball and softball teams over 1 season. All sliding attempts were recorded during each game and recorded as headfirst, feetfirst, or diveback. Base type, playing surface, and field conditions were also noted. Injury exposure rates by game exposures and sliding/diveback exposures. Data were collected from 153 baseball games and 166 softball games. A greater proportion of slides were associated with injury in softball than in baseball (42.0 and 4.9 per 1000 slides; P < 0.05). Headfirst slides led to more injuries than feetfirst slides in baseball (16.8 vs 0 per 1000 slides; P < 0.05) but not in softball (55 vs 35 per 1000 slides; P = 0.74). More powerful studies are required to determine whether efforts to prevent baseball sliding injuries at the high school level should focus on better education in sliding technique or changes in equipment. Softball players are vulnerable to injury when wearing inadequate protective sliding apparel.

A method for normalizing pathology images to improve feature extraction for quantitative pathology.

PubMed

Tam, Allison; Barker, Jocelyn; Rubin, Daniel

2016-01-01

With the advent of digital slide scanning technologies and the potential proliferation of large repositories of digital pathology images, many research studies can leverage these data for biomedical discovery and to develop clinical applications. However, quantitative analysis of digital pathology images is impeded by batch effects generated by varied staining protocols and staining conditions of pathological slides. To overcome this problem, this paper proposes a novel, fully automated stain normalization method to reduce batch effects and thus aid research in digital pathology applications. Their method, intensity centering and histogram equalization (ICHE), normalizes a diverse set of pathology images by first scaling the centroids of the intensity histograms to a common point and then applying a modified version of contrast-limited adaptive histogram equalization. Normalization was performed on two datasets of digitized hematoxylin and eosin (H&E) slides of different tissue slices from the same lung tumor, and one immunohistochemistry dataset of digitized slides created by restaining one of the H&E datasets. The ICHE method was evaluated based on image intensity values, quantitative features, and the effect on downstream applications, such as a computer aided diagnosis. For comparison, three methods from the literature were reimplemented and evaluated using the same criteria. The authors found that ICHE not only improved performance compared with un-normalized images, but in most cases showed improvement compared with previous methods for correcting batch effects in the literature. ICHE may be a useful preprocessing step a digital pathology image processing pipeline.

Effects of off-axis elliptical training on reducing pain and improving knee function in individuals with patellofemoral pain

PubMed Central

Tsai, Liang-Ching; Lee, Song Joo; Yang, Aaron J.; Ren, Yupeng; Press, Joel M.; Zhang, Li-Qun

2014-01-01

Objective To examine whether an off-axis elliptical training program reduces pain and improves knee function in individuals with patellofemoral pain (PFP). Design Controlled laboratory study, pre-test-post-test. Setting University rehabilitation center. Participants Twelve adult subjects with PFP. Interventions Subjects with PFP completed an exercise program consisting of 18 sessions of lower extremity off-axis training using a custom-made elliptical trainer that allows frontal-plane sliding and transverse-plane pivoting of the footplates. Main Outcome Measures Changes in knee pain and function post-training and 6 weeks following training were evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and International Knee Documentation Committee (IKDC) scores. Lower extremity off-axis control was assessed by pivoting and sliding instability, calculated as the root mean square (RMS) of the footplate pivoting angle and sliding distance during elliptical exercise. Subjects’ single-leg hop distance and proprioception in detecting lower extremity pivoting motion were also evaluated. Results Subjects reported significantly greater KOOS and IKDC scores (increased by 12–18 points) and hop distance (increased by 0.2 m) following training. A significant decrease in the pivoting and sliding RMS was also observed following training. Additionally, subjects with PFP demonstrated improved pivoting proprioception when tested under a minimum-weight-bearing position. Conclusions An off-axis elliptical training program was effective in enhancing lower extremity neuromuscular control on the frontal and transverse planes, reducing pain and improving knee function in persons with PFP. PMID:25591131

Seismo-Live: Training in Seismology with Jupyter Notebooks

NASA Astrophysics Data System (ADS)

Krischer, Lion; Tape, Carl; Igel, Heiner

2016-04-01

Seismological training tends to occur within the isolation of a particular institution with a limited set of tools (codes, libraries) that are often not transferrable outside. Here, we propose to overcome these limitations with a community-driven library of Jupyter notebooks dedicated to training on any aspect of seismology for purposes of education and outreach, on-site or archived tutorials for codes, classroom instruction, and research. A Jupyter notebook (jupyter.org) is an open-source interactive computational environment that allows combining code execution, rich text, mathematics, and plotting. It can be considered a platform that supports reproducible research, as all inputs and outputs may be stored. Text, external graphics, equations can be handled using Markdown (incl. LaTeX) format. Jupyter notebooks are driven by standard web browsers, can be easily exchanged in text format, or converted to other documents (e.g. PDF, slide shows). They provide an ideal format for practical training in seismology. A pilot-platform was setup with a dedicated server such that the Jupyter notebooks can be run in any browser (PC, notepad, smartphone). We show the functionalities of the Seismo-Live platform with examples from computational seismology, seismic data access and processing using the ObsPy library, seismic inverse problems, and others. The current examples are all using the Python programming language but any free language can be used. Potentially, such community platforms could be integrated with the EPOS-IT infrastructure and extended to other fields of Earth sciences.

Implementing virtual microscopy improves outcomes in a hematology morphology course.

PubMed

Brueggeman, Mauri S; Swinehart, Cheryl; Yue, Mary Jane; Conway-Klaassen, Janice M; Wiesner, Stephen M

2012-01-01

In this study, we evaluated the efficacy of virtual microscopy as the primary mode of laboratory instruction in undergraduate level clinical hematology teaching. Distance education (DE) has become a popular option for expanding education and optimizing expenses but continues to be controversial. The challenge of delivering an equitable curriculum to distant locations along with the need to preserve our slide collection directed our effort to digitize the slide sets used in our teaching laboratories. Students enrolled at two performance sites were randomly assigned to either traditional microscopy (TM) or virtual microscopy (VM) instruction. The VM group performed significantly better than the TM group. We anticipate that this approach will play a central role in the distributed delivery of hematology through distance education as new programs are initiated to address workforce shortage needs.

Flagging threshold optimization for manual blood smear review in primary care laboratory.

PubMed

Bihl, Pierre-Adrien

2018-04-01

Manual blood smear review is required when an anomaly detected by the automated hematologic analyzer triggers a flag. Our will through this study is to optimize these flagging thresholds for manual slide review in order to limit workload, while insuring clinical care through no extra false-negative. Flagging causes of 4,373 samples were investigated by manual slide review, after having been run on ADVIA 2120i. A set of 6 user-adjustments is proposed. By implementing all recommendations that we made, false-positive rate falls from 81.8% to 58.6%, while PPV increases from 18.2% to 23.7%. Hence, use of such optimized thresholds enables us to maximize efficiency without altering clinical care, but each laboratory should establish its own criteria to take into consideration local distinctive features.

Active Learning with Ubiquitous Presenter and Tablet PCs

NASA Astrophysics Data System (ADS)

Price, Edward; Simon, B.

2006-12-01

Ubiquitous Presenter (UP)* is a digital presentation system that facilitates spontaneity and interactivity in the classroom. Using the system, an instructor with a Tablet PC can spontaneously modify prepared slides. Furthermore, students with web-enabled devices can add digital 'ink' or text to the instructor's slides and submit them to the instructor during class. We have used this system to facilitate interactive engagement techniques in an introductory physics class where approximately one-third of the students had access to a Tablet PC during class. Class time was used for Interactive Lecture Demonstrations, Peer Instruction, and group problem solving. We describe the implementation of these active learning activities with UP and Tablet PCs, show examples of student contributions, and describe the impact on the classroom setting. *http://up.ucsd.edu/about/

A parameter estimation algorithm for spatial sine testing - Theory and evaluation

NASA Technical Reports Server (NTRS)

Rost, R. W.; Deblauwe, F.

1992-01-01

This paper presents the theory and an evaluation of a spatial sine testing parameter estimation algorithm that uses directly the measured forced mode of vibration and the measured force vector. The parameter estimation algorithm uses an ARMA model and a recursive QR algorithm is applied for data reduction. In this first evaluation, the algorithm has been applied to a frequency response matrix (which is a particular set of forced mode of vibration) using a sliding frequency window. The objective of the sliding frequency window is to execute the analysis simultaneously with the data acquisition. Since the pole values and the modal density are obtained from this analysis during the acquisition, the analysis information can be used to help determine the forcing vectors during the experimental data acquisition.

Nonlinear control of magnetic bearings

NASA Technical Reports Server (NTRS)

Pradeep, A. K.; Gurumoorthy, R.

1994-01-01

In this paper we present a variety of nonlinear controllers for the magnetic bearing that ensure both stability and robustness. We utilize techniques of discontinuous control to design novel control laws for the magnetic bearing. We present in particular sliding mode controllers, time optimal controllers, winding algorithm based controllers, nested switching controllers, fractional controllers, and synchronous switching controllers for the magnetic bearing. We show existence of solutions to systems governed by discontinuous control laws, and prove stability and robustness of the chosen control laws in a rigorous setting. We design sliding mode observers for the magnetic bearing and prove the convergence of the state estimates to their true values. We present simulation results of the performance of the magnetic bearing subject to the aforementioned control laws, and conclude with comments on design.

Assessing the Relative Mobility of Submarine Landslides from Deposit Morphology and Physical Properties: an Example from Nankai Trough, Offshore Japan

NASA Astrophysics Data System (ADS)

Sawyer, D.; Moore, Z. T.

2014-12-01

A prominent landslide deposit in the Slope Basin seaward of the Megasplay Fault in the Nankai Trough was emplaced by a high-mobility landslide based on analysis of physical properties and seismic geomorphology. Slide acceleration is a critical variable that determines amplitude of slide-generated tsunami but is many times a variable with large uncertainty. In controlled laboratory experiments, the ratio of the shear stress to yield strength, defined as the Flow Factor, controls a wide spectrum of mass movement styles from slow, retrogressive failure to rapid, liquefied flows. We apply the laboratory Flow Factor approach to a natural landslide in the Nankai Trough by constraining pre-failure particle size analysis and porosity. Several mass transport deposits (MTDs), were drilled and cored at Site C0021 in the Nankai Trough during Integrated Ocean Drilling Program (IODP) Expedition 338. The largest, MTD-6, occurs at 133-176 meters below seafloor and occurred approximately 0.87 Mya. Slide volume is 2 km3, transport distance is 5 km, and average deposit thickness is 50 m (maximum 180 m). Pre-failure water content was estimated from shallow sediments at Site C0018 (porosity = 72%). The average grain size distribution is 39% clay-sized, 58% silt-sized, and 3% sand-size particles as determined by hydrometer analyses of the MTD. Together, the porosity and clay fraction predict a Flow Factor of approximately 4, which corresponds to a relatively high mobility slide. We interpret this result to indicate the landslide that created MTD-6 was a single event that transported the slide mass relatively rapidly as opposed to a slow, episodic landslide event. This is supported by the observation of a completely evacuated source area with no remnant blocks or retrogressive headscarp and the internally chaotic seismic facies with large entrained blocks. Future works will focus on the tsunamigenic potential of this high mobility slide. This approach can be extended to other field settings characterized by fine-grained siliciclastics and where porosity and clay content are known.

Diagnostic Accuracy of History and Physical Examination of Superior Labrum Anterior-Posterior Lesions

PubMed Central

Michener, Lori A.; Doukas, William C.; Murphy, Kevin P.; Walsworth, Matthew K.

2011-01-01

Context: Type I superior labrum anterior-posterior (SLAP) lesions involve degenerative fraying and probably are not the cause of shoulder pain. Type II to IV SLAP lesions are tears of the labrum. Objective: To determine the diagnostic accuracy of patient history and the active compression, anterior slide, and crank tests for type I and type II to IV SLAP lesions. Design: Cohort study. Setting: Clinic. Patients or Other Participants: Fifty-five patients (47 men, 8 women; age = 40.6 ± 15.1 years) presenting with shoulder pain. Intervention(s): For each patient, an orthopaedic surgeon conducted a clinical examination of history of trauma; sudden onset of symptoms; history of popping, clicking, or catching; age; and active compression, crank, and anterior slide tests. The reference standard was the intraoperative diagnosis. The operating surgeon was blinded to the results of the clinical examination. Main Outcome Measure(s): Diagnostic utility was calculated using the receiver operating characteristic curve and area under the curve (AUC), sensitivity, specificity, positive likelihood ratio (+LR), and negative likelihood ratio (−LR). Forward stepwise binary regression was used to determine a combination of tests for diagnosis. Results: No history item or physical examination test had diagnostic accuracy for type I SLAP lesions (n = 13). The anterior slide test had utility (AUC = 0.70, +LR = 2.25, −LR = 0.44) to confirm and exclude type II to IV SLAP lesions (n = 10). The combination of a history of popping, clicking, or catching and the anterior slide test demonstrated diagnostic utility for confirming type II to IV SLAP lesions (+LR = 6.00). Conclusions: The anterior slide test had limited diagnostic utility for confirming and excluding type II to IV SLAP lesions; diagnostic values indicated only small shifts in probability. However, the combination of the anterior slide test with a history of popping, clicking, or catching had moderate diagnostic utility for confirming type II to IV SLAP lesions. No single item or combination of history items and physical examination tests had diagnostic utility for type I SLAP lesions. PMID:21944065

A multioutput LLC-type parallel resonant converter

NASA Astrophysics Data System (ADS)

Liu, Rui; Lee, C. Q.; Upadhyay, Anand K.

1992-07-01

When an LLC-type parallel resonant converter (LLC-PRC) operates above resonant frequency, the switching transistors can be turned off at zero voltage. Further study reveals that the LLC-PRC possesses the advantage of lower converter voltage gain as compared with the conventional PRC. Based on analytic results, a complete set of design curves is obtained, from which a systematic design procedure is developed. Experimental results from a 150 W 150 kHz multioutput LLC-type PRC power supply are presented.

Development and validation of a registry-based definition of eosinophilic esophagitis in Denmark

PubMed Central

Dellon, Evan S; Erichsen, Rune; Pedersen, Lars; Shaheen, Nicholas J; Baron, John A; Sørensen, Henrik T; Vyberg, Mogens

2013-01-01

AIM: To develop and validate a case definition of eosinophilic esophagitis (EoE) in the linked Danish health registries. METHODS: For case definition development, we queried the Danish medical registries from 2006-2007 to identify candidate cases of EoE in Northern Denmark. All International Classification of Diseases-10 (ICD-10) and prescription codes were obtained, and archived pathology slides were obtained and re-reviewed to determine case status. We used an iterative process to select inclusion/exclusion codes, refine the case definition, and optimize sensitivity and specificity. We then re-queried the registries from 2008-2009 to yield a validation set. The case definition algorithm was applied, and sensitivity and specificity were calculated. RESULTS: Of the 51 and 49 candidate cases identified in both the development and validation sets, 21 and 24 had EoE, respectively. Characteristics of EoE cases in the development set [mean age 35 years; 76% male; 86% dysphagia; 103 eosinophils per high-power field (eos/hpf)] were similar to those in the validation set (mean age 42 years; 83% male; 67% dysphagia; 77 eos/hpf). Re-review of archived slides confirmed that the pathology coding for esophageal eosinophilia was correct in greater than 90% of cases. Two registry-based case algorithms based on pathology, ICD-10, and pharmacy codes were successfully generated in the development set, one that was sensitive (90%) and one that was specific (97%). When these algorithms were applied to the validation set, they remained sensitive (88%) and specific (96%). CONCLUSION: Two registry-based definitions, one highly sensitive and one highly specific, were developed and validated for the linked Danish national health databases, making future population-based studies feasible. PMID:23382628

Pressure vessel sliding support unit and system using the sliding support unit

DOEpatents

Breach, Michael R.; Keck, David J.; Deaver, Gerald A.

2013-01-15

Provided is a sliding support and a system using the sliding support unit. The sliding support unit may include a fulcrum capture configured to attach to a support flange, a fulcrum support configured to attach to the fulcrum capture, and a baseplate block configured to support the fulcrum support. The system using the sliding support unit may include a pressure vessel, a pedestal bracket, and a plurality of sliding support units.

Velocity dependence of sliding friction on a crystalline surface

PubMed Central

Apostoli, Christian; Giusti, Giovanni; Ciccoianni, Jacopo; Riva, Gabriele; Capozza, Rosario; Woulaché, Rosalie Laure; Vanossi, Andrea; Panizon, Emanuele

2017-01-01

We introduce and study a minimal 1D model for the simulation of dynamic friction and dissipation at the atomic scale. This model consists of a point mass (slider) that moves over and interacts weakly with a linear chain of particles interconnected by springs, representing a crystalline substrate. This interaction converts a part of the kinetic energy of the slider into phonon waves in the substrate. As a result, the slider experiences a friction force. As a function of the slider speed, we observe dissipation peaks at specific values of the slider speed, whose nature we understand by means of a Fourier analysis of the excited phonon modes. By relating the phonon phase velocities with the slider velocity, we obtain an equation whose solutions predict which phonons are being excited by the slider moving at a given speed. PMID:29114445

Cloth-Based Power Shirt for Wearable Energy Harvesting and Clothes Ornamentation.

PubMed

Li, Suling; Zhong, Qize; Zhong, Junwen; Cheng, Xiaofeng; Wang, Bo; Hu, Bin; Zhou, Jun

2015-07-15

Harvesting ambient mechanical energy from human body motion has attracted great research interest. In this work, a power shirt based on triboelectrification and the electrostatic induction effect between fluorinated ethylene propylene (FEP) and external objects is demonstrated. This power shirt can effectively convert the ambient mechanical energy into electric power, and the working mechanism is systematically discussed. A maximum short-circuit current density of ∼0.37 μA/cm2 and a maximum peak power density of ∼4.65 μW/cm2 were achieved. Simultaneously, 11 blue LEDs were lit by sliding the sleeve and power shirt, indicating the potential application of the power shirt in clothes ornamentation and risk warning. This study develops an efficient path for harvesting human body energy and promoting the development of wearable electronics and smart garments.

In vitro evaluation of resistance to sliding in self-ligating and conventional bracket systems during dental alignment.

PubMed

Cordasco, Giancarlo; Lo Giudice, Antonino; Militi, Angela; Nucera, Riccardo; Triolo, Giuseppe; Matarese, Giovanni

2012-08-01

To investigate the resistance to sliding (RS) in self-ligating and conventional ligation bracket systems at 5 different second-order bracket angulations by using low-stiffness alignment wires in a 3-bracket experimental model and to verify the performance of the main RS components in both systems when these wires are used. Interactive self-ligating brackets with closed and open slides were used for the self-ligating (SL) and conventional ligation (CL) groups, respectively; elastomeric ligatures (1 mm inner diameter) were used in the latter system. The alignment wire used was 0.014 inch heat-activated NiTi (austenitic finish temperature set at 36℃ by the manufacturer). A custom-made testing machine was used to measure frictional resistance. Tests were repeated 5 times at every angulation simulated. All data were analyzed statistically. The RS increased significantly with increasing angulation in both SL and CL groups (p < 0.0001). However, the RS values were significantly higher at every angulation (p < 0.0001) in the CL group. Despite the relevance of the binding phenomenon, ligation forces predominantly affect the RS when low-stiffness alignment wires are used.

In vitro evaluation of resistance to sliding in self-ligating and conventional bracket systems during dental alignment

PubMed Central

Cordasco, Giancarlo; Lo Giudice, Antonino; Militi, Angela; Nucera, Riccardo; Triolo, Giuseppe

2012-01-01

Objective To investigate the resistance to sliding (RS) in self-ligating and conventional ligation bracket systems at 5 different second-order bracket angulations by using low-stiffness alignment wires in a 3-bracket experimental model and to verify the performance of the main RS components in both systems when these wires are used. Methods Interactive self-ligating brackets with closed and open slides were used for the self-ligating (SL) and conventional ligation (CL) groups, respectively; elastomeric ligatures (1 mm inner diameter) were used in the latter system. The alignment wire used was 0.014 inch heat-activated NiTi (austenitic finish temperature set at 36℃ by the manufacturer). A custom-made testing machine was used to measure frictional resistance. Tests were repeated 5 times at every angulation simulated. All data were analyzed statistically. Results The RS increased significantly with increasing angulation in both SL and CL groups (p < 0.0001). However, the RS values were significantly higher at every angulation (p < 0.0001) in the CL group. Conclusions Despite the relevance of the binding phenomenon, ligation forces predominantly affect the RS when low-stiffness alignment wires are used. PMID:23112953

Positive sliding mode control for blood glucose regulation

NASA Astrophysics Data System (ADS)

Menani, Karima; Mohammadridha, Taghreed; Magdelaine, Nicolas; Abdelaziz, Mourad; Moog, Claude H.

2017-11-01

Biological systems involving positive variables as concentrations are some examples of so-called positive systems. This is the case of the glycemia-insulinemia system considered in this paper. To cope with these physical constraints, it is shown that a positive sliding mode control (SMC) can be designed for glycemia regulation. The largest positive invariant set (PIS) is obtained for the insulinemia subsystem in open and closed loop. The existence of a positive SMC for glycemia regulation is shown here for the first time. Necessary conditions to design the sliding surface and the discontinuity gain are derived to guarantee a positive SMC for the insulin dynamics. SMC is designed to be positive everywhere in the largest closed-loop PIS of plasma insulin system. Two-stage SMC is employed; the last stage SMC2 block uses the glycemia error to design the desired insulin trajectory. Then the plasma insulin state is forced to track the reference via SMC1. The resulting desired insulin trajectory is the required virtual control input of the glycemia system to eliminate blood glucose (BG) error. The positive control is tested in silico on type-1 diabetic patients model derived from real-life clinical data.

Bathymetry at the head of the Cape Fear Slide, offshore North Carolina

USGS Publications Warehouse

Schmuck, Eric A.; Popenoe, Peter; Paull, Charles K.; Brown, Carol

1992-01-01

The Cape Fear Slide is the largest mass-movement that has been observed on the U.S. Atlantic Margin. It is located off the Carolinas on the continental rise in approximately 1,200-5,500 m water depth and extends downslope for over 300 km (Popenoe, 1982). These maps show the bathymetry at the head of the Cape Fear Slide as interpreted from single-channel 3.5 kHz seismic-reflection profiles and mid-range Sea Marc I sidescan sonar imagery (Popenoe, 1985; Popenoe and others, 1991; Schmuck, 1991). The 3.5 kHz data consist of over 1000 km of profiles that were collected in 1988 for the University of North Carolina, Department of Geology. The UNC 3.5 kHz data were used as the main data set in interpreting the bathymetry. The sidescan sonar data were collected in 1980 by the U.S. Geological Survey in cooperation with the Lamont-Doherty Geological Observatory for the U.S. Bureau of Land Management Environmental Studies Program. Only 28 km (5 km swath width) of the sidescan data were used in the interpretation to identify the morphology of the main slump scarp and visible secondary scarps.

Women and Work--New Options. A Guide to Nonprint Media.

ERIC Educational Resources Information Center

Artel, Linda; Wheat, Valerie

The purpose of this guide is to gather together in one volume information about nonprint media dealing with new career options for women. The 112 films, filmstrips, videotapes and cassettes, slides, photograph sets and games included in the guide are listed in alphabetical order by title. For each entry the following information is provided:…

Activated Biological Filters (ABF Towers). Instructor's Guide. Biological Treatment Process Control.

ERIC Educational Resources Information Center

Wooley, John F.

This instructor's manual contains materials needed to teach a two-lesson unit on activated bio-filters (ABF). These materials include: (1) an overview of the two lessons; (2) lesson plans; (3) lecture outlines (keyed to a set of slides designed for use with the lessons); (4) overhead transparency masters; (5) worksheets for each lesson (with…

Integrating SFA Technology into the Sales Curriculum: Helping Students Understand What, Why, and When

ERIC Educational Resources Information Center

Jelinek, Ronald

2018-01-01

While sales force automation (SFA) and customer relationship management are important concepts in business-to-business selling, many instructors struggle to effectively integrate these topics into their curriculum. The research described in this article offers a role play and two coordinating sets of slides that aim to help students better…

Health Instruction Packages: Consumer--Your Heart and Blood Pressure.

ERIC Educational Resources Information Center

Woods, James W.; And Others

Text, illustrations, and exercises are utilized in this set of learning modules to instruct the general public in the prevention and treatment of heart disease. The first module, by James W. Woods, presents a medical definition of high blood pressure, reviews its causes and effects, and discusses its treatment. A script to a slide version of this…

International Lunar Network (ILN) Anchor Nodes

NASA Technical Reports Server (NTRS)

Cohen, Barbara A.

2009-01-01

This slide presentation reviews the United States' contribution to the International Lunar Network (ILN) project, the Anchor Nodes project. The ILN is an initiative of 9 national space agencies to establish a set of robotic geophysical monitoring stations on the surface of the Moon. The project is aimed at furthering the understanding of the lunar composition, and interior structure.

Contrasting Urban Lifestyles in Brazil. A Precollegiate Curriculum Unit: Grades Six-Twelve.

ERIC Educational Resources Information Center

Stanford Univ., CA. Stanford Program on International and Cross Cultural Education.

This unit, designed for use with students in grades 6-12, concerns the diverse and unifying forces that characterize life in Brazil's urban centers. Comprised of seven lessons and used with a set of slides, lesson 1, "Geography," distinguishes Brazil from other South American countries through an examination of the country's geographic…

Sliding U.S. Dollar Packs a Wallop to Wallets Worldwide

ERIC Educational Resources Information Center

Bowman, Quinn

2008-01-01

The dollar, once one of the world's strongest currencies, has fallen dramatically in recent years--a development impacting attitudes from corporate boardrooms to the sets of music videos where artists are choosing to flash the euro over American cash. When measured against a collection of other leading worldwide currencies--like the European euro,…

The Education and Lifestyle of the Chinese Literati. Lesson Plan.

ERIC Educational Resources Information Center

Smithsonian Institution, Washington, DC. Arthur M. Sackler Gallery.

This teaching package describes the education and lifestyle of the Chinese literati, popular from the Ming to the Qing dynasties (1368-1911). It consists of four lesson plans and a teacher's guide to a slide set. The latter illustrates painting formats popular during the late Ming period (1573-1644), hanging scrolls, handscrolls, the album leaf,…

Geoscience Videos and Their Role in Supporting Student Learning

ERIC Educational Resources Information Center

Wiggen, Jennifer; McDonnell, David

2017-01-01

A series of short (5 to 7 minutes long) geoscience videos were created to support student learning in a flipped class setting for an introductory geology class at North Carolina State University. Videos were made using a stylus, tablet, microphone, and video editing software. Essentially, we narrate a slide, sketch a diagram, or explain a figure…

How to Set Up a Resource Center to be Compatible with an Outdoor Program.

ERIC Educational Resources Information Center

Stilson, Jan

A materials collection can provide indirect experiences that will supplement the direct learning experiences offered by an outdoor education nature center. The Instructional Materials Center at Lorado Taft Field Campus provides such multiple learning experiences as it offers print media as well as slides, films, tapes, and projection and field…

A Semantic Parsing Method for Mapping Clinical Questions to Logical Forms

PubMed Central

Roberts, Kirk; Patra, Braja Gopal

2017-01-01

This paper presents a method for converting natural language questions about structured data in the electronic health record (EHR) into logical forms. The logical forms can then subsequently be converted to EHR-dependent structured queries. The natural language processing task, known as semantic parsing, has the potential to convert questions to logical forms with extremely high precision, resulting in a system that is usable and trusted by clinicians for real-time use in clinical settings. We propose a hybrid semantic parsing method, combining rule-based methods with a machine learning-based classifier. The overall semantic parsing precision on a set of 212 questions is 95.6%. The parser’s rules furthermore allow it to “know what it does not know”, enabling the system to indicate when unknown terms prevent it from understanding the question’s full logical structure. When combined with a module for converting a logical form into an EHR-dependent query, this high-precision approach allows for a question answering system to provide a user with a single, verifiably correct answer. PMID:29854217

Robust Timing Synchronization in Aeronautical Mobile Communication Systems

NASA Technical Reports Server (NTRS)

Xiong, Fu-Qin; Pinchak, Stanley

2004-01-01

This work details a study of robust synchronization schemes suitable for satellite to mobile aeronautical applications. A new scheme, the Modified Sliding Window Synchronizer (MSWS), is devised and compared with existing schemes, including the traditional Early-Late Gate Synchronizer (ELGS), the Gardner Zero-Crossing Detector (GZCD), and the Sliding Window Synchronizer (SWS). Performance of the synchronization schemes is evaluated by a set of metrics that indicate performance in digital communications systems. The metrics are convergence time, mean square phase error (or root mean-square phase error), lowest SNR for locking, initial frequency offset performance, midstream frequency offset performance, and system complexity. The performance of the synchronizers is evaluated by means of Matlab simulation models. A simulation platform is devised to model the satellite to mobile aeronautical channel, consisting of a Quadrature Phase Shift Keying modulator, an additive white Gaussian noise channel, and a demodulator front end. Simulation results show that the MSWS provides the most robust performance at the cost of system complexity. The GZCD provides a good tradeoff between robustness and system complexity for communication systems that require high symbol rates or low overall system costs. The ELGS has a high system complexity despite its average performance. Overall, the SWS, originally designed for multi-carrier systems, performs very poorly in single-carrier communications systems. Table 5.1 in Section 5 provides a ranking of each of the synchronization schemes in terms of the metrics set forth in Section 4.1. Details of comparison are given in Section 5. Based on the results presented in Table 5, it is safe to say that the most robust synchronization scheme examined in this work is the high-sample-rate Modified Sliding Window Synchronizer. A close second is its low-sample-rate cousin. The tradeoff between complexity and lowest mean-square phase error determines the rankings of the Gardner Zero-Crossing Detector and both versions of the Early-Late Gate Synchronizer. The least robust models are the high and low-sample-rate Sliding Window Synchronizers. Consequently, the recommended replacement synchronizer for NASA's Advanced Air Transportation Technologies mobile aeronautical communications system is the high-sample-rate Modified Sliding Window Synchronizer. By incorporating this synchronizer into their system, NASA can be assured that their system will be operational in extremely adverse conditions. The quick convergence time of the MSWS should allow the use of high-level protocols. However, if NASA feels that reduced system complexity is the most important aspect of their replacement synchronizer, the Gardner Zero-Crossing Detector would be the best choice.

Effect of sliding velocity on the tribological behavior of copper and associated nanostructure development

NASA Astrophysics Data System (ADS)

Emge, Andrew

The unlubricated sliding of metals is important in many mechanical devices covering a wide range of sliding velocities. However, the effect of sliding velocity on the tribological behavior of unlubricated metals has not been widely studied. Similarly, the relationship between microstructures developed at high sliding velocities and tribological behavior has not been studied in depth. Microstructures produced at low sliding velocities have been studied extensively and commonly include nanocrystalline or fine grained material near the sliding surface with heavily deformed microstructures further from the surface. The current research relates two aspects of the sliding friction of ductile metals, the effect of sliding velocity and the production of nanocrystalline tribomaterial. The project focused on the effects of sliding velocity on the frictional behavior of oxygen free high conductivity (OFHC) copper sliding against 440C stainless steel, Nitronic 40 stainless steel, and copper. Low velocity tests were performed with a pin on disk tribometer. High velocity tests were performed with a rotating barrel gas gun (RBGG) which combined impact with sliding. The RBGG provides sliding velocities as high as 5.5 m/s and impact velocities as high as 12 m/s while maintaining sliding times on the order of tens of microseconds. Changes in the coefficient of friction, microstructure, and composition were studied. Surface and subsurface microstructures of the worn samples were characterized with a range of instruments including scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS), focused ion beam (FIB) milling and imaging, transmission electron microscopy (TEM) with EDS, orientation imaging microscopy (OIM), and nanoindentation. In the case of self-mated copper the sliding velocity had little effect on the coefficient of friction for both experimental apparatuses. For the case of copper sliding against 440C stainless steel on the pin on disk system the friction was found to increase with sliding velocity and was strongly influenced by material transfer from the copper to the steel pin. An increase in the coefficient of friction with sliding velocity was observed for the sliding of OFHC copper against Nitronic 40 steel in RBGG tests. The increase in the coefficient of friction was correlated to an increase in subsurface plastic deformation and grain refinement. The growth of the nanocrystalline tribolayer in copper after sliding against 440C stainless steel at varying times was studied at sliding velocities of 0.05 and 1.0 m/s. A sliding velocity of 0.05 m/s produced a consistent nanocrystalline layer in as little as 10 s. The thickness of the nanocrystalline layer grew to an average thickness of 3 microm after 10 ks of sliding, but large variations in thickness were observed. A sliding velocity of 1.0 m/s produced a continuous nanocrystalline layer after 10 s of sliding. Ledges developed on the wear tracks at longer sliding times which greatly influenced the tribolayer thickness making it difficult to quantify. Dynamic recrystallization of the tribolayer also led to difficulties in measuring its thickness.

Wall Area of Influence and Growing Wall Heat Transfer due to Sliding Bubbles in Subcooled Boiling Flow

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

Yoo, Junsoo; Estrada-Perez, Carlos E.; Hassan, Yassin A.

A variety of dynamical features of sliding bubbles and their impact on wall heat transfer were observed at subcooled flow boiling conditions in a vertical square test channel. Among the wide range of parameters observed, we particularly focus in this paper on (i) the sliding bubbles’ effect on wall heat transfer (supplemantry discussion to the authors’ previous work in Yoo et al. (2016a,b)) and (ii) the wall area influenced by sliding bubbles in subcooled boiling flow. At first, this study reveals that the degree of wall heat transfer improvement due to sliding bubbles depended less on the wall superheat conditionmore » as the mass flux increased. Also, the sliding bubble trajectory was found to be one of the critical factors in order to properly describe the wall heat transfer associated with sliding bubbles. In particular, the wall area influenced by sliding bubbles depended strongly on both sliding bubble trajectory and sliding bubble size; the sliding bubble trajectory was also observed to be closely related to the sliding bubble size. Importantly, these results indicate the limitation of current approach in CFD analyses especially for the wall area of bubble influence. In addition, the analyses on the temporal fraction of bubbles’ residence (FR) along the heated wall show that the sliding bubbles typically travel through narrow path with high frequency while the opposite was observed downstream. That is, both FR and sliding bubble trajectory depended substantially on the distance from nucleation site, which is expected to be similar for the quenching heat transfer mode induced by sliding bubbles.« less

Power converters for the 120 V bus supply control

NASA Astrophysics Data System (ADS)

Elisabelar, Christian

1993-03-01

Power converters for the 120 V bus supply control in such projects as Columbus and Hermes are addressed. Because of the power levels involved and the existing state of the art, several converter modules need to be connected in parallel to supply a single bus. To simplify the study, the power of each converter is set at around 1 kW. Many converter structures which satisfy requirement specifications and several solutions, with or without galvanic insulation, are proposed. The choice and sizing of the converter structure are considered. Stress factors and available technology are selection criteria in determining the most suitable structures. The dimensions of each structure, taking into account the rules of space design enable efficiency to be analytically estimated and it is subsequently verified experimentally. The converter command and its functional performance are then addressed. Numerical simulations with SUCCESS software are run to observe the actual operation of the power part of the converter and to develop the command law with its regulation parameters. The converter is simulated in its entirety and different transients are studied like load variation, no load operating point, short circuit. The response time, stability and behavior under disturbed conditions are thus known. A comparison of the various structures studied enabled the optimal converter to be chosen for some 120 V regulated bus applications.

Friction between various self-ligating brackets and archwire couples during sliding mechanics.

PubMed

Stefanos, Sennay; Secchi, Antonino G; Coby, Guy; Tanna, Nipul; Mante, Francis K

2010-10-01

The aim of this study was to evaluate the frictional resistance between active and passive self-ligating brackets and 0.019 × 0.025-in stainless steel archwire during sliding mechanics by using an orthodontic sliding simulation device. Maxillary right first premolar active self-ligating brackets In-Ovation R, In-Ovation C (both, GAC International, Bohemia, NY), and SPEED (Strite Industries, Cambridge, Ontario, Canada), and passive self-ligating brackets SmartClip (3M Unitek, Monrovia, Calif), Synergy R (Rocky Mountain Orthodontics, Denver, Colo), and Damon 3mx (Ormco, Orange, Calif) with 0.022-in slots were used. Frictional force was measured by using an orthodontic sliding simulation device attached to a universal testing machine. Each bracket-archwire combination was tested 30 times at 0° angulation relative to the sliding direction. Statistical comparisons were performed with 1-way analysis of variance (ANOVA) followed by Dunn multiple comparisons. The level of statistical significance was set at P <0.05. The Damon 3mx brackets had significantly the lowest mean static frictional force (8.6 g). The highest mean static frictional force was shown by the SPEED brackets (83.1 g). The other brackets were ranked as follows, from highest to lowest, In-Ovation R, In-Ovation C, SmartClip, and Synergy R. The mean static frictional forces were all statistically different. The ranking of the kinetic frictional forces of bracket-archwire combinations was the same as that for static frictional forces. All bracket-archwire combinations showed significantly different kinetic frictional forces except SmartClip and In-Ovation C, which were not significantly different from each other. Passive self-ligating brackets have lower static and kinetic frictional resistance than do active self-ligating brackets with 0.019 × 0.025-in stainless steel wire. Copyright © 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

Toward implementation of a regional quality assurance program in cytopathology: the Hong Kong experience.

PubMed

Ng, Wai-Kuen; Chiu, Conrad S C; Cheng, Yue; Chan, Eva T Y; Chiu, Fanny L L; Collins, Robert J

2006-01-01

To develop a local quality assurance program in cytopathology based on circulation of patient specimens on glass slides, with limited resources. A working group was set up for design and running of the program. Participation is on a laboratory basis. The scope and frequency of testing are defined. Well-documented cases (including gynecologic, nongynecologic and fine needle aspiration cytology) with commonly encountered diagnoses are collected. Consensus concerning the diagnosis, interpretive menu and scoring system is sought before the actual slide circulations using express mail. After returning their answers to the program organizer, the participating laboratories receive immediate feedback on their scores, with reference answers, explanatory notes, "whole-mount" images of glass slides and cumulative responses of peer laboratories for on-site checking. At the end of each year, an electronic file containing representative photomicrographs of all cases examined is provided to individual laboratories for their permanent records and training purposes. The program was launched in mid-2003. There were 24 and 27 participating laboratories from Hong Kong (and Macau) in 2003 and 2004, respectively. To date, >150 well-documented cytology cases are available in the slide pool and ready for circulation. As the revenue is mainly to cover the expenses of express mail, the program can be carried out at a relatively low cost. In order to have any cytology quality assurance program accepted by local laboratories, it has to be fair and practical. Strict confidentiality needs to be observed throughout the process. This program emphasizes both performance assessment and educational value. Adequate representation from experienced local cytology workers, detailed documentation support from authorities and assistance from dedicated staff are essential to the success of any external proficiency testing scheme. Regular review and evaluation are also necessary for continuous improvement. The Hong Kong experience can serve as an example of running a glass slide-based cytology quality assurance program in a small region with limited resources.

Wirelessly powered microfluidic dielectrophoresis devices using printable RF circuits.

PubMed

Qiao, Wen; Cho, Gyoujin; Lo, Yu-Hwa

2011-03-21

We report the first microfluidic device integrated with a printed RF circuit so the device can be wirelessly powered by a commercially available RFID reader. For conventional dielectrophoresis devices, electrical wires are needed to connect the electric components on the microchip to external equipment such as power supplies, amplifiers, function generators, etc. Such a procedure is unfamiliar to most clinicians and pathologists who are used to working with a microscope for examination of samples on microscope slides. The wirelessly powered device reported here eliminates the entire need for wire attachments and external instruments so the operators can use the device in essentially the same manner as they do with microscope slides. The integrated circuit can be fabricated on a flexible plastic substrate at very low cost using a roll-to-roll printing method. Electrical power at 13.56 MHz transmitted by a radio-frequency identification (RFID) reader is inductively coupled to the printed RFIC and converted into 10 V DC (direct current) output, which provides sufficient power to drive a microfluidic device to manipulate biological particles such as beads and proteins via the DC dielectrophoresis (DC-DEP) effect. To our best knowledge, this is the first wirelessly powered microfluidic dielectrophoresis device. Although the work is preliminary, the device concept, the architecture, and the core technology are expected to stimulate many efforts in the future and transform the technology to a wide range of clinical and point-of-care applications. This journal is © The Royal Society of Chemistry 2011

Non-linear control of the output stage of a solar microinverter

NASA Astrophysics Data System (ADS)

Lopez-Santos, Oswaldo; Garcia, Germain; Martinez-Salamero, Luis; Avila-Martinez, Juan C.; Seguier, Lionel

2017-01-01

This paper presents a proposal to control the output stage of a two-stage solar microinverter to inject real power into the grid. The input stage of the microinverter is used to extract the maximum available power of a photovoltaic module enforcing a power source behavior in the DC-link to feed the output stage. The work here reported is devoted to control a grid-connected power source inverter with a high power quality level at the grid side ensuring the power balance of the microinverter regulating the voltage of the DC-link. The proposed control is composed of a sinusoidal current reference generator and a cascade type controller composed by a current tracking loop and a voltage regulation loop. The current reference is obtained using a synchronized generator based on phase locked loop (PLL) which gives the shape, the frequency and phase of the current signal. The amplitude of the reference is obtained from a simple controller regulating the DC-link voltage. The tracking of the current reference is accomplished by means of a first-order sliding mode control law. The solution takes advantage of the rapidity and inherent robustness of the sliding mode current controller allowing a robust behavior in the regulation of the DC-link using a simple linear controller. The analytical expression to determine the power quality indicators of the micro-inverter's output is theoretically solved giving expressions relating the converter parameters. The theoretical approach is validated using simulation and experimental results.

Heat Source/Sink in a Magneto-Hydrodynamic Non-Newtonian Fluid Flow in a Porous Medium: Dual Solutions.

PubMed

Hayat, Tasawar; Awais, Muhammad; Imtiaz, Amna

2016-01-01

This communication deals with the properties of heat source/sink in a magneto-hydrodynamic flow of a non-Newtonian fluid immersed in a porous medium. Shrinking phenomenon along with the permeability of the wall is considered. Mathematical modelling is performed to convert the considered physical process into set of coupled nonlinear mathematical equations. Suitable transformations are invoked to convert the set of partial differential equations into nonlinear ordinary differential equations which are tackled numerically for the solution computations. It is noted that dual solutions for various physical parameters exist which are analyzed in detail.

Laboratory observations of fault strength in response to changes in normal stress

USGS Publications Warehouse

Kilgore, Brian D.; Lozos, Julian; Beeler, Nicholas M.; Oglesby, David

2012-01-01

Changes in fault normal stress can either inhibit or promote rupture propagation, depending on the fault geometry and on how fault shear strength varies in response to the normal stress change. A better understanding of this dependence will lead to improved earthquake simulation techniques, and ultimately, improved earthquake hazard mitigation efforts. We present the results of new laboratory experiments investigating the effects of step changes in fault normal stress on the fault shear strength during sliding, using bare Westerly granite samples, with roughened sliding surfaces, in a double direct shear apparatus. Previous experimental studies examining the shear strength following a step change in the normal stress produce contradictory results: a set of double direct shear experiments indicates that the shear strength of a fault responds immediately, and then is followed by a prolonged slip-dependent response, while a set of shock loading experiments indicates that there is no immediate component, and the response is purely gradual and slip-dependent. In our new, high-resolution experiments, we observe that the acoustic transmissivity and dilatancy of simulated faults in our tests respond immediately to changes in the normal stress, consistent with the interpretations of previous investigations, and verify an immediate increase in the area of contact between the roughened sliding surfaces as normal stress increases. However, the shear strength of the fault does not immediately increase, indicating that the new area of contact between the rough fault surfaces does not appear preloaded with any shear resistance or strength. Additional slip is required for the fault to achieve a new shear strength appropriate for its new loading conditions, consistent with previous observations made during shock loading.

Determination of esophageal eosinophil counts and other histologic features of eosinophilic esophagitis by pathology trainees is highly accurate

PubMed Central

Rusin, Spencer; Covey, Shannon; Perjar, Irina; Hollyfield, Johnny; Speck, Olga; Woodward, Kimberly; Woosley, John T.; Dellon, Evan S.

2017-01-01

Summary Many studies of eosinophilic esophagitis (EoE) utilize expert pathology review, but it is unknown whether less experienced pathologists can reliably assess EoE histology. We aimed to determine whether trainee pathologists can accurately quantify esophageal eosinophil counts and identify associated histologic features of EoE, as compared to expert pathologists. We used a set of 40 digitized slides from patients with varying degrees of esophageal eosinophilia. Each of six trainee pathologists underwent a teaching session and used our validated protocol to determine eosinophil counts and associated EoE findings. The same slides had previously been evaluated by expert pathologists, and these results comprised the gold standard. Eosinophil counts were correlated, and agreement was calculated for the diagnostic threshold of 15 eosinophils per high-power field (eos/hpf) as well as for associated EoE findings. Peak eosinophil counts were highly correlated between the trainees and the gold standard (Rho ranged from 0.87–0.92; p<0.001 for all). Peak counts were also highly correlated between trainees (0.75–0.91; p<0.001), and results were similar for mean counts. Agreement was excellent for determining if a count exceeded the diagnostic threshold (kappa ranged from 0.83 to 0.89; p<0.001). Agreement was very good for eosinophil degranulation (kappa 0.54 to 0.83; p<0.01) and spongiosis (kappa 0.44–0.87; p<0.01), but was lower for eosinophil microabscesses (kappa 0.37–0.64; p<0.01). In conclusion, using a teaching session, digitized slide set, and validated protocol, the agreement between pathology trainees and expert pathologists for determining eosinophil counts was excellent. Agreement was very good for eosinophil degranulation and spongiosis, but less so for microabscesses. PMID:28041975

Determination of esophageal eosinophil counts and other histologic features of eosinophilic esophagitis by pathology trainees is highly accurate.

PubMed

Rusin, Spencer; Covey, Shannon; Perjar, Irina; Hollyfield, Johnny; Speck, Olga; Woodward, Kimberly; Woosley, John T; Dellon, Evan S

2017-04-01

Many studies of eosinophilic esophagitis (EoE) use expert pathology review, but it is unknown whether less experienced pathologists can reliably assess EoE histology. We aimed to determine whether trainee pathologists can accurately quantify esophageal eosinophil counts and identify associated histologic features of EoE, as compared with expert pathologists. We used a set of 40 digitized slides from patients with varying degrees of esophageal eosinophilia. Each of 6 trainee pathologists underwent a teaching session and used our validated protocol to determine eosinophil counts and associated EoE findings. The same slides had previously been evaluated by expert pathologists, and these results comprised the criterion standard. Eosinophil counts were correlated, and agreement was calculated for the diagnostic threshold of 15 eosinophils per high-power field as well as for associated EoE findings. Peak eosinophil counts were highly correlated between the trainees and the criterion standard (ρ ranged from 0.87 to 0.92; P<.001 for all). Peak counts were also highly correlated between trainees (0.75-0.91; P<.001), and results were similar for mean counts. Agreement was excellent for determining if a count exceeded the diagnostic threshold (κ ranged from 0.83 to 0.89; P<.001). Agreement was very good for eosinophil degranulation (κ = 0.54-0.83; P<.01) and spongiosis (κ = 0.44-0.87; P<.01) but was lower for eosinophil microabscesses (κ = 0.37-0.64; P<.01). In conclusion, using a teaching session, digitized slide set, and validated protocol, the agreement between pathology trainees and expert pathologists for determining eosinophil counts was excellent. Agreement was very good for eosinophil degranulation and spongiosis but less so for microabscesses. Copyright © 2016 Elsevier Inc. All rights reserved.

Onsite Portable Alarm System - Its Merit and Application

NASA Astrophysics Data System (ADS)

Saita, J.; Sato, T.; Nakamura, Y.

2007-12-01

Recently an existence of the earthquake early warning system (EEWS) becomes popular. In general, the EEWS will be installed in a fixed observation site and it may consist of several separated components such as a sensing portion, A/D converter, an information processing potion and so on. The processed information for warning may be transmitted to network via fixed communication line, and therefore this kind of alarm system is called as Network Alarm System. On the other hand, after the severe earthquake damage, it is very important to save the disaster victims immediately. These rescue staffs are also under the risk of aftershocks and need a local alarm not depending on the network, so this kind of alarm can be called as Onsite Alarm. But the common early warning system is too complex to set onsite temporary, and even if possible to install, the alarm is too late to receive at the epicentral area. However, the new generation earthquake early warning system FREQL can issue the P wave alarm by minimum 0.2 seconds after P wave detection. And FREQL is characterized as the unique all-in-one seismometer with power unit. At the time of the 2004 Niigata-Ken-Chuetsu earthquake, a land slide attacked a car just passing. A hyper rescue team of Tokyo Fire Department pulled the survivor, one baby, from the land slide area. During their activity the rescue team was exposed to the risk of secondary hazards caused by the aftershocks. It was clear that it is necessary to use a portable warning system to issue the onsite P wave alarm. Because FREQL was originally developed as portable equipment, Tokyo Fire Department asked us to modify it to the portable equipment with the loud sound and the light signal. In this moment, this portable FREQL has equipped in nation wide. When the hyper rescue team of Tokyo Fire Department was sent to Pakistan as a task force for rescue work of the 2005 Pakistan earthquake, the portable FREQL was used as important onsite portable warning system and P wave alarms was actually issued by three times during the rescue work. Although this is one example for the actual application of portable onsite alarm, it is possible to apply the other field as the construction field. In this presentation, Portable Onsite Alarm is discussed from views of its necessity and application.

Portable convertible blast effects shield

DOEpatents

Pastrnak, John W [Livermore, CA; Hollaway, Rocky [Modesto, CA; Henning, Carl D [Livermore, CA; Deteresa, Steve [Livermore, CA; Grundler, Walter [Hayward, CA; Hagler, Lisle B [Berkeley, CA; Kokko, Edwin [Dublin, CA; Switzer, Vernon A [Livermore, CA

2011-03-15

A rapidly deployable portable convertible blast effects shield/ballistic shield includes a set two or more frusto-conically-tapered telescoping rings operably connected to each other to convert between a telescopically-collapsed configuration for storage and transport, and a telescopically-extended upright configuration forming an expanded inner volume. In a first embodiment, the upright configuration provides blast effects shielding, such as against blast pressures, shrapnel, and/or fire balls. And in a second embodiment, the upright configuration provides ballistic shielding, such as against incoming weapons fire, shrapnel, etc. Each ring has a high-strength material construction, such as a composite fiber and matrix material, capable of substantially inhibiting blast effects and impinging projectiles from passing through the shield. And the set of rings are releasably securable to each other in the telescopically-extended upright configuration by the friction fit of adjacent pairs of frusto-conically-tapered rings to each other.

RandomSpot: A web-based tool for systematic random sampling of virtual slides.

PubMed

Wright, Alexander I; Grabsch, Heike I; Treanor, Darren E

2015-01-01

This paper describes work presented at the Nordic Symposium on Digital Pathology 2014, Linköping, Sweden. Systematic random sampling (SRS) is a stereological tool, which provides a framework to quickly build an accurate estimation of the distribution of objects or classes within an image, whilst minimizing the number of observations required. RandomSpot is a web-based tool for SRS in stereology, which systematically places equidistant points within a given region of interest on a virtual slide. Each point can then be visually inspected by a pathologist in order to generate an unbiased sample of the distribution of classes within the tissue. Further measurements can then be derived from the distribution, such as the ratio of tumor to stroma. RandomSpot replicates the fundamental principle of traditional light microscope grid-shaped graticules, with the added benefits associated with virtual slides, such as facilitated collaboration and automated navigation between points. Once the sample points have been added to the region(s) of interest, users can download the annotations and view them locally using their virtual slide viewing software. Since its introduction, RandomSpot has been used extensively for international collaborative projects, clinical trials and independent research projects. So far, the system has been used to generate over 21,000 sample sets, and has been used to generate data for use in multiple publications, identifying significant new prognostic markers in colorectal, upper gastro-intestinal and breast cancer. Data generated using RandomSpot also has significant value for training image analysis algorithms using sample point coordinates and pathologist classifications.

Automated detection of prostate cancer in digitized whole-slide images of H and E-stained biopsy specimens

NASA Astrophysics Data System (ADS)

Litjens, G.; Ehteshami Bejnordi, B.; Timofeeva, N.; Swadi, G.; Kovacs, I.; Hulsbergen-van de Kaa, C.; van der Laak, J.

2015-03-01

Automated detection of prostate cancer in digitized H and E whole-slide images is an important first step for computer-driven grading. Most automated grading algorithms work on preselected image patches as they are too computationally expensive to calculate on the multi-gigapixel whole-slide images. An automated multi-resolution cancer detection system could reduce the computational workload for subsequent grading and quantification in two ways: by excluding areas of definitely normal tissue within a single specimen or by excluding entire specimens which do not contain any cancer. In this work we present a multi-resolution cancer detection algorithm geared towards the latter. The algorithm methodology is as follows: at a coarse resolution the system uses superpixels, color histograms and local binary patterns in combination with a random forest classifier to assess the likelihood of cancer. The five most suspicious superpixels are identified and at a higher resolution more computationally expensive graph and gland features are added to refine classification for these superpixels. Our methods were evaluated in a data set of 204 digitized whole-slide H and E stained images of MR-guided biopsy specimens from 163 patients. A pathologist exhaustively annotated the specimens for areas containing cancer. The performance of our system was evaluated using ten-fold cross-validation, stratified according to patient. Image-based receiver operating characteristic (ROC) analysis was subsequently performed where a specimen containing cancer was considered positive and specimens without cancer negative. We obtained an area under the ROC curve of 0.96 and a 0.4 specificity at a 1.0 sensitivity.

Towards machine learned quality control: A benchmark for sharpness quantification in digital pathology.

PubMed

Campanella, Gabriele; Rajanna, Arjun R; Corsale, Lorraine; Schüffler, Peter J; Yagi, Yukako; Fuchs, Thomas J

2018-04-01

Pathology is on the verge of a profound change from an analog and qualitative to a digital and quantitative discipline. This change is mostly driven by the high-throughput scanning of microscope slides in modern pathology departments, reaching tens of thousands of digital slides per month. The resulting vast digital archives form the basis of clinical use in digital pathology and allow large scale machine learning in computational pathology. One of the most crucial bottlenecks of high-throughput scanning is quality control (QC). Currently, digital slides are screened manually to detected out-of-focus regions, to compensate for the limitations of scanner software. We present a solution to this problem by introducing a benchmark dataset for blur detection, an in-depth comparison of state-of-the art sharpness descriptors and their prediction performance within a random forest framework. Furthermore, we show that convolution neural networks, like residual networks, can be used to train blur detectors from scratch. We thoroughly evaluate the accuracy of feature based and deep learning based approaches for sharpness classification (99.74% accuracy) and regression (MSE 0.004) and additionally compare them to domain experts in a comprehensive human perception study. Our pipeline outputs spacial heatmaps enabling to quantify and localize blurred areas on a slide. Finally, we tested the proposed framework in the clinical setting and demonstrate superior performance over the state-of-the-art QC pipeline comprising commercial software and human expert inspection by reducing the error rate from 17% to 4.7%. Copyright © 2017. Published by Elsevier Ltd.

A method for normalizing pathology images to improve feature extraction for quantitative pathology

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

Tam, Allison; Barker, Jocelyn; Rubin, Daniel

Purpose: With the advent of digital slide scanning technologies and the potential proliferation of large repositories of digital pathology images, many research studies can leverage these data for biomedical discovery and to develop clinical applications. However, quantitative analysis of digital pathology images is impeded by batch effects generated by varied staining protocols and staining conditions of pathological slides. Methods: To overcome this problem, this paper proposes a novel, fully automated stain normalization method to reduce batch effects and thus aid research in digital pathology applications. Their method, intensity centering and histogram equalization (ICHE), normalizes a diverse set of pathology imagesmore » by first scaling the centroids of the intensity histograms to a common point and then applying a modified version of contrast-limited adaptive histogram equalization. Normalization was performed on two datasets of digitized hematoxylin and eosin (H&E) slides of different tissue slices from the same lung tumor, and one immunohistochemistry dataset of digitized slides created by restaining one of the H&E datasets. Results: The ICHE method was evaluated based on image intensity values, quantitative features, and the effect on downstream applications, such as a computer aided diagnosis. For comparison, three methods from the literature were reimplemented and evaluated using the same criteria. The authors found that ICHE not only improved performance compared with un-normalized images, but in most cases showed improvement compared with previous methods for correcting batch effects in the literature. Conclusions: ICHE may be a useful preprocessing step a digital pathology image processing pipeline.« less

Deep Learning for Classification of Colorectal Polyps on Whole-slide Images.

PubMed

Korbar, Bruno; Olofson, Andrea M; Miraflor, Allen P; Nicka, Catherine M; Suriawinata, Matthew A; Torresani, Lorenzo; Suriawinata, Arief A; Hassanpour, Saeed

2017-01-01

Histopathological characterization of colorectal polyps is critical for determining the risk of colorectal cancer and future rates of surveillance for patients. However, this characterization is a challenging task and suffers from significant inter- and intra-observer variability. We built an automatic image analysis method that can accurately classify different types of colorectal polyps on whole-slide images to help pathologists with this characterization and diagnosis. Our method is based on deep-learning techniques, which rely on numerous levels of abstraction for data representation and have shown state-of-the-art results for various image analysis tasks. Our method covers five common types of polyps (i.e., hyperplastic, sessile serrated, traditional serrated, tubular, and tubulovillous/villous) that are included in the US Multisociety Task Force guidelines for colorectal cancer risk assessment and surveillance. We developed multiple deep-learning approaches by leveraging a dataset of 2074 crop images, which were annotated by multiple domain expert pathologists as reference standards. We evaluated our method on an independent test set of 239 whole-slide images and measured standard machine-learning evaluation metrics of accuracy, precision, recall, and F1 score and their 95% confidence intervals. Our evaluation shows that our method with residual network architecture achieves the best performance for classification of colorectal polyps on whole-slide images (overall accuracy: 93.0%, 95% confidence interval: 89.0%-95.9%). Our method can reduce the cognitive burden on pathologists and improve their efficacy in histopathological characterization of colorectal polyps and in subsequent risk assessment and follow-up recommendations.

Transmission geometry laser ablation into a non-contact liquid vortex capture probe for mass spectrometry imaging.

PubMed

Ovchinnikova, Olga S; Bhandari, Deepak; Lorenz, Matthias; Van Berkel, Gary J

2014-08-15

Capture of material from a laser ablation plume into a continuous flow stream of solvent provides the means for uninterrupted sampling, transport and ionization of collected material for coupling with mass spectral analysis. Reported here is the use of vertically aligned transmission geometry laser ablation in combination with a new non-contact liquid vortex capture probe coupled with electrospray ionization for spot sampling and chemical imaging with mass spectrometry. A vertically aligned continuous flow liquid vortex capture probe was positioned directly underneath a sample surface in a transmission geometry laser ablation (355 nm, 10 Hz, 7 ns pulse width) set up to capture into solution the ablated material. The outlet of the vortex probe was coupled to the Turbo V™ ion source of an AB SCIEX TripleTOF 5600+ mass spectrometer. System operation and performance metrics were tested using inked patterns and thin tissue sections. Glass slides and slides designed especially for laser capture microdissection, viz., DIRECTOR(®) slides and PEN 1.0 (polyethylene naphthalate) membrane slides, were used as sample substrates. The estimated capture efficiency of laser-ablated material was 24%, which was enabled by the use of a probe with large liquid surface area (~2.8 mm(2) ) and with gravity to help direct ablated material vertically down towards the probe. The swirling vortex action of the liquid surface potentially enhanced capture and dissolution not only of particulates, but also of gaseous products of the laser ablation. The use of DIRECTOR(®) slides and PEN 1.0 (polyethylene naphthalate) membrane slides as sample substrates enabled effective ablation of a wide range of sample types (basic blue 7, polypropylene glycol, insulin and cyctochrome c) without photodamage using a UV laser. Imaging resolution of about 6 µm was demonstrated for stamped ink on DIRECTOR(®) slides based on the ability to distinguish features present both in the optical and in the chemical image. This imaging resolution was 20 times better than the previous best reported results with laser ablation/liquid sample capture mass spectrometry imaging. Using thin sections of brain tissue the chemical image of a selected lipid was obtained with an estimated imaging resolution of about 50 µm. A vertically aligned, transmission geometry laser ablation liquid vortex capture probe, electrospray ionization mass spectrometry system provides an effective means for spatially resolved spot sampling and imaging with mass spectrometry. Published in 2014. This article is a U.S. Government work and is in the public domain in the USA.

Using slides to test for changes in crown defoliation assessment methods. Part I: Visual assessment of slides.

PubMed

Dobbertin, Matthias; Hug, Christian; Mizoue, Nobuya

2004-11-01

In this study we used photographs of tree crowns to test whether the assessment methods for tree defoliation in Switzerland have changed over time. We randomly selected 24 series of slides of Norway spruce with field assessments made between 1986 and 1995. The slides were randomly arranged and assessed by three experts without prior knowledge of the year when the slide was taken or the tree number. Defoliation was assessed using the Swiss reference photo guide. Although the correlations between the field assessments and slide assessments were high (Spearman's rank correlation coefficient ranged between 0.79 and 0.83), we found significant differences between field and slide assessments (4.3 to 9% underprediction by the slide assessors) and between the slide assessments. However, no significant trends in field assessment methods could be detected. When the mean differences between field and slide assessments were subtracted, in some years, field assessors consistently underpredicted (1990, 1992) or overpredicted defoliation (1987, 1991). Defoliation tended to be overpredicted in slides taken against the light, and underpredicted for trees with more than 25% crown overlap. We conclude that slide series can be used to detect changes in assessment methods. However, potential observer bias calls for more objective methods of assessment.

Review of Solids Handling. Instructor's Guide. Biological Treatment Process Control.

ERIC Educational Resources Information Center

Carnegie, John W.

This unit (which consists of a single lesson) summarizes and reviews most of the solids handling processes in common use in municipal treatment plants. The instructor's guide for the unit includes: (1) an overview of the lesson; (2) lesson plan; (3) lecture outline (keyed to a set of 72 slides); (4) student worksheet (with answers); and (5) two…

Matter-Energy Interactions in Natural Systems. Science III and IIIA.

ERIC Educational Resources Information Center

Pfeiffer, Carl H.

The two student notebooks in this set provide the basic outline and assignments for the third year of a four year senior high school unified science program. This course is the more technical of the two third-year courses offered in the program. The first unit, Extensions of the Particle Theories, deals with slide rule review, molecular theory and…

What Are Altmetrics? Are They Important? | Poster

Cancer.gov

Altmetrics, also known as alternative metrics, offer a way to gauge the attention that research output (such as articles, data sets, program code, slide decks, and posters) is generating on social media, reference sharing sites (such as Mendeley), blogs, and other online media.? The term “altmetrics” was coined on Twitter in 2010 by Jason Priem, then a graduate student at the

A Laboratory Activity on the Eddy Current Brake

ERIC Educational Resources Information Center

Molina-Bolivar, J. A.; Abella-Palacios, A. J.

2012-01-01

The aim of this paper is to introduce a simple and low-cost experimental setup that can be used to study the eddy current brake, which considers the motion of a sliding magnet on an inclined conducting plane in terms of basic physical principles. We present a set of quantitative experiments performed to study the influence of the geometrical and…

Sharing Our Land With Wildlife. Narrative Guide for Color Slide Set and Film Strip C-177.

ERIC Educational Resources Information Center

Soil Conservation Service (USDA), Washington, DC.

The coexistence of wildlife with American agriculture is explored in this pamphlet. Studied is the importance and value of good soil and water conservation to conserve wildlife, relating it to the feeding and living habits of wildlife, economic and aesthetic values of wildlife, the growing of specific plants and provision of watering places for…

Plugged in or Tuned out? Students and Educators Reflect on Current Technology in the Classroom

ERIC Educational Resources Information Center

Blankenship, Mark

2010-01-01

Not long ago, television sets in classrooms were a novel idea and most professors could remember the days of slide rules, mimeograph machines, and manual typewriters. Now, even DVD players can seem quaint. But education has been altered by the breathtakingly rapid technological advancements of the last 10 years, and just like the rest of the…

Creating Visual Aids with Graphic Organisers on an Infinite Canvas--The Impact on the Presenter

ERIC Educational Resources Information Center

Casteleyn, Jordi; Mottart, Andre; Valcke, Martin

2015-01-01

Instead of the traditional set of slides, the visual aids of a presentation can now be graphic organisers (concept maps, knowledge maps, mind maps) on an infinite canvas. Constructing graphic organisers has a beneficial impact on learning, but this topic has not been studied in the context of giving a presentation. The present study examined this…

Presentation Extensions of the SOAP

NASA Technical Reports Server (NTRS)

Carnright, Robert; Stodden, David; Coggi, John

2009-01-01

A set of extensions of the Satellite Orbit Analysis Program (SOAP) enables simultaneous and/or sequential presentation of information from multiple sources. SOAP is used in the aerospace community as a means of collaborative visualization and analysis of data on planned spacecraft missions. The following definitions of terms also describe the display modalities of SOAP as now extended: In SOAP terminology, View signifies an animated three-dimensional (3D) scene, two-dimensional still image, plot of numerical data, or any other visible display derived from a computational simulation or other data source; a) "Viewport" signifies a rectangular portion of a computer-display window containing a view; b) "Palette" signifies a collection of one or more viewports configured for simultaneous (split-screen) display in the same window; c) "Slide" signifies a palette with a beginning and ending time and an animation time step; and d) "Presentation" signifies a prescribed sequence of slides. For example, multiple 3D views from different locations can be crafted for simultaneous display and combined with numerical plots and other representations of data for both qualitative and quantitative analysis. The resulting sets of views can be temporally sequenced to convey visual impressions of a sequence of events for a planned mission.

Fundamentals of the Slide Library.

ERIC Educational Resources Information Center

Boerner, Susan Zee

This paper is an introduction to the fundamentals of the art (including architecture) slide library, with some emphasis on basic procedures of the science slide library. Information in this paper is particularly relevant to the college, university, and museum slide library. Topics addressed include: (1) history of the slide library; (2) duties of…

Virtual microscopy in a veterinary curriculum.

PubMed

Sims, Michael H; Mendis-Handagama, Chamindrani; Moore, Robert N

2007-01-01

Teaching faculty in the University of Tennessee College of Veterinary Medicine assist students in their professional education by providing a new way of viewing microscopic slides digitally. Faculty who teach classes in which glass slides are used participate in a program called Virtual Microscopy. Glass slides are digitized using a state-of-the-art integrated system, and a personal computer functions as the "microscope." Additionally, distribution of the interactive images is enhanced because they are available to students online. The digital slide offers equivalent quality and resolution to the original glass slide viewed on a microscope and has several additional advantages over microscopes. Students can choose to examine the entire slide at any of several objectives; they are able to access the slides (called WebSlides) from the college's server, using either Internet Explorer or a special browser developed by Bacus Laboratories, Inc.,(a) called the WebSlide browser, which lets the student simultaneously view a low-objective image and one or two high-objective images of the same slide. The student can "move the slide" by clicking and dragging the image to a new location. Easy archiving, annotation of images, and Web conferencing are additional features of the system.

Modelling the initiation of basal sliding

NASA Astrophysics Data System (ADS)

Mantelli, E.; Schoof, C.

2017-12-01

The initiation of basal sliding is a thermally-controlled process that affects ice speed, englacial heat transport, and melt water production at the bed, and ultimately influences the large-scale dynamics of ice sheets. From a modelling perspective, describing the onset of sliding in thin-film models suitable for ice sheet scale simulations is problematic. In particular, previous work concluded that, under shallow-ice mechanics, the scenario of a hard switch from frozen to molten bed leads to an infinite vertical velocity at the onset, and higher-order mechanical formulations are needed to describe sliding initiation. An alternative view considers the occurrence of subtemperate sliding, which allows for a smooth sliding velocity across the onset. However, the sliding velocity decreases rapidly as temperature drops below the melting point, thus raising the issue of whether a mechanical model that does not resolve the ice sheet thickness scale is ever appropriate to model the onset of sliding. In this study we first present a boundary layer model for the hard switch scenario. Our analysis, which considers a thermo-mechanically coupled Stokes flow near the onset, shows that the abrupt onset of sliding is never possible. In fact, the acceleration of ice flow deflects the flowlines towards the bed, which freezes again immediately downstream to the onset. This leads to the conclusion that the sliding velocity must change smoothly across the onset, thus the temperature dependence of sliding needs to be taken into account. In this context, we examine a limiting case of standard temperature-dependent sliding laws, where sliding onset takes the form of an extended transition region interposed between fully frozen and temperate bed. In the transition region basal temperature is at the melting point, and the sliding velocity varies smoothly as dictated by the energy budget of the bed. As the extent of this region is not small compared to the ice sheet length scale, we couple this description of sliding initiation to a shallow-ice model, which is appropriate so long as sliding velocities are not large. We present numerical and analytical results concerning the steady states and the stability of this ice sheet model, and discuss implications of sliding initiation with respect to pattern formation.

Training a cell-level classifier for detecting basal-cell carcinoma by combining human visual attention maps with low-level handcrafted features

PubMed Central

Corredor, Germán; Whitney, Jon; Arias, Viviana; Madabhushi, Anant; Romero, Eduardo

2017-01-01

Abstract. Computational histomorphometric approaches typically use low-level image features for building machine learning classifiers. However, these approaches usually ignore high-level expert knowledge. A computational model (M_im) combines low-, mid-, and high-level image information to predict the likelihood of cancer in whole slide images. Handcrafted low- and mid-level features are computed from area, color, and spatial nuclei distributions. High-level information is implicitly captured from the recorded navigations of pathologists while exploring whole slide images during diagnostic tasks. This model was validated by predicting the presence of cancer in a set of unseen fields of view. The available database was composed of 24 cases of basal-cell carcinoma, from which 17 served to estimate the model parameters and the remaining 7 comprised the evaluation set. A total of 274 fields of view of size 1024×1024  pixels were extracted from the evaluation set. Then 176 patches from this set were used to train a support vector machine classifier to predict the presence of cancer on a patch-by-patch basis while the remaining 98 image patches were used for independent testing, ensuring that the training and test sets do not comprise patches from the same patient. A baseline model (M_ex) estimated the cancer likelihood for each of the image patches. M_ex uses the same visual features as M_im, but its weights are estimated from nuclei manually labeled as cancerous or noncancerous by a pathologist. M_im achieved an accuracy of 74.49% and an F-measure of 80.31%, while M_ex yielded corresponding accuracy and F-measures of 73.47% and 77.97%, respectively. PMID:28382314

External quality assessment of AFB smear microscopy performances and its associated factors in selected private health facilities in Addis Ababa, Ethiopia.

PubMed

Mosissa, Lemi; Kebede, Abebaw; Mindaye, Tedla; Getahun, Muluwork; Tulu, Sisay; Desta, Kassu

2016-01-01

Tuberculosis (TB) is still a public health problem in sub Saharan African countries. In resource-limited settings, TB diagnosis relies on sputum smear microscopy, with low and variable sensitivities, especially in paucibacillary pediatric and HIV-associated TB patients. Tuberculosis microscopy centers have several weaknesses like overworking, insufficiently trained personnel, inconsistent reagent supplies, and poorly maintained equipments; thus, there is a critical need for investments in laboratory infrastructure, capacity building, and quality assurance schemes. The performance of TB microscopy centers in the private health facilities in Addis Ababa is not known so far. The main objective of the study was to assess laboratory performance of acid fast bacilli (AFB) smear microscopy and its associated factors in selected private health facilities in Addis Ababa, Ethiopia. A cross-sectional study was conducted in 33 selected private health facilities of Addis Ababa, Ethiopia comprising 7 hospitals, 2 NGO health centers, 23 higher clinics and 1 diagnostic laboratory that provide AFB smear microscopy services. The study was conducted from January to April 2014. A total of 283 stained sputum smears were randomly collected from participant laboratories for blinded rechecking, 320 panel slides were sent to 32 microscopy centers to evaluate their performance on AFB reading, staining and reporting. Checklists were used to assess quality issues of laboratories. Data were captured, cleaned, and analyzed using SPSS version 16.0; χ(2) tests, kappa statistics were used for comparison purpose. P value < 0.05 considered statistically significant. Among the 32 participant laboratories, 2-scored 100%, 15 scored 80-95% & the remaining 15 scored 50-75% for overall proficiency test performance. There were 10 (3.15%) major errors and 121 (37.8%) minor errors. The sensitivity, specificity, PPV and NPV of panel reading by microscopy centers were 89%, 96%, 96%, and 90% respectively. Out of 283 randomly selected slides for blind rechecking, 11 (3.9%) slides interpreted falsely for AFB, with overall agreement of 97.5%, sensitivity of 88.4% and specificity of 99.3%. In terms of slide quality assessment, 71.6% of AFB slides were graded as good for evenness, cleanness, thickness, size, staining and labeling. The performance score for AFB slide evenness was 56.9% (161 slides) and for labeling quality was 90.8% (257 slides); having significant difference in slide quality (p value < 0.05). On-site evaluation indicated problems in terms of infrastructure, standard operating procedure, reagent quality; equipment maintenance, data management and training issues. Most of the health facilities had poor maintenance scheme for microscope (53.5%) and poor inventory management (25.0%) system. Microscopy centers that scored a proficiency of 75.5%; which is below the acceptable minimum score of 80% and an overall error rate of 3.9% for blinded rechecking needs attention. Moreover, there are gaps identified through on site assessment including poor SOP, reagent quality, equipment maintenance, data management & lack of updated training on AFB microscopy techniques, requiring a concerted effort to alleviate the bottle neck problems and strengthening the public private partnership to control TB.

External quality assessment of AFB smear microscopy performances and its associated factors in selected private health facilities in Addis Ababa, Ethiopia

PubMed Central

Mosissa, Lemi; Kebede, Abebaw; Mindaye, Tedla; Getahun, Muluwork; Tulu, Sisay; Desta, Kassu

2016-01-01

Tuberculosis (TB) is still a public health problem in sub Saharan African countries. In resource-limited settings, TB diagnosis relies on sputum smear microscopy, with low and variable sensitivities, especially in paucibacillary pediatric and HIV-associated TB patients. Tuberculosis microscopy centers have several weaknesses like overworking, insufficiently trained personnel, inconsistent reagent supplies, and poorly maintained equipments; thus, there is a critical need for investments in laboratory infrastructure, capacity building, and quality assurance schemes. The performance of TB microscopy centers in the private health facilities in Addis Ababa is not known so far. The main objective of the study was to assess laboratory performance of acid fast bacilli (AFB) smear microscopy and its associated factors in selected private health facilities in Addis Ababa, Ethiopia. A cross-sectional study was conducted in 33 selected private health facilities of Addis Ababa, Ethiopia comprising 7 hospitals, 2 NGO health centers, 23 higher clinics and 1 diagnostic laboratory that provide AFB smear microscopy services. The study was conducted from January to April 2014. A total of 283 stained sputum smears were randomly collected from participant laboratories for blinded rechecking, 320 panel slides were sent to 32 microscopy centers to evaluate their performance on AFB reading, staining and reporting. Checklists were used to assess quality issues of laboratories. Data were captured, cleaned, and analyzed using SPSS version 16.0; χ2 tests, kappa statistics were used for comparison purpose. P value < 0.05 considered statistically significant. Among the 32 participant laboratories, 2-scored 100%, 15 scored 80-95% & the remaining 15 scored 50-75% for overall proficiency test performance. There were 10 (3.15%) major errors and 121 (37.8%) minor errors. The sensitivity, specificity, PPV and NPV of panel reading by microscopy centers were 89%, 96%, 96%, and 90% respectively. Out of 283 randomly selected slides for blind rechecking, 11 (3.9%) slides interpreted falsely for AFB, with overall agreement of 97.5%, sensitivity of 88.4% and specificity of 99.3%. In terms of slide quality assessment, 71.6% of AFB slides were graded as good for evenness, cleanness, thickness, size, staining and labeling. The performance score for AFB slide evenness was 56.9% (161 slides) and for labeling quality was 90.8% (257 slides); having significant difference in slide quality (p value < 0.05). On-site evaluation indicated problems in terms of infrastructure, standard operating procedure, reagent quality; equipment maintenance, data management and training issues. Most of the health facilities had poor maintenance scheme for microscope (53.5%) and poor inventory management (25.0%) system. Microscopy centers that scored a proficiency of 75.5%; which is below the acceptable minimum score of 80% and an overall error rate of 3.9% for blinded rechecking needs attention. Moreover, there are gaps identified through on site assessment including poor SOP, reagent quality, equipment maintenance, data management & lack of updated training on AFB microscopy techniques, requiring a concerted effort to alleviate the bottle neck problems and strengthening the public private partnership to control TB. PMID:27642463

Selected Landscape Plants. Slide Script.

ERIC Educational Resources Information Center

McCann, Kevin

This slide script, part of a series of slide scripts designed for use in vocational agriculture classes, deals with commercially important woody ornamental landscape plants. Included in the script are narrations for use with a total of 253 slides illustrating 92 different plants. Several slides are used to illustrate each plant: besides a view of…

The Munson-Nygren slide: A major lower-slope slide off Georges Bank

USGS Publications Warehouse

O'Leary, Dennis W.

1986-01-01

The Munson-Nygren slide is a large compound slide located between Munson and Nygren Canyons below 1900 m depth on the Continental Slope off Georges Bank. Its structural and morphological features are recognized in high-resolution seismic-reflection profiles. The slide comprises an axial trough which has a relief as great as 325 m and a width of 6-10 km. The trough is flanked by displaced and disrupted strata for a total lateral extent of approximately 20 km and a downslope extent of at least 35 km. The slide is unrelated genetically to the adjacent canyons and may postdate Munson Canyon. There is evidence of plastic deformation at the base of the section subjected to sliding. Certain features of the slide complex resemble those seen in landforms on the Laurentian Rise and attributed by Emery et al.* * Emery et al. (1970). to the 1929 Grand Banks earthquake. The Munson-Nygren slide may have been triggered by a large earthquake in late Pleistocene time or later. Destructional landforms associated with the slide are similar to those widely present along the lower slope off Georges Bank. ?? 1986.

Modulation and control of matrix converter for aerospace application

NASA Astrophysics Data System (ADS)

Kobravi, Keyhan

In the context of modern aircraft systems, a major challenge is power conversion to supply the aircraft's electrical instruments. These instruments are energized through a fixed-frequency internal power grid. In an aircraft, the available sources of energy are a set of variable-speed generators which provide variable-frequency ac voltages. Therefore, to energize the internal power grid of an aircraft, the variable-frequency ac voltages should be converted to a fixed-frequency ac voltage. As a result, an ac to ac power conversion is required within an aircraft's power system. This thesis develops a Matrix Converter to energize the aircraft's internal power grid. The Matrix Converter provides a direct ac to ac power conversion. A major challenge of designing Matrix Converters for aerospace applications is to minimize the volume and weight of the converter. These parameters are minimized by increasing the switching frequency of the converter. To design a Matrix Converter operating at a high switching frequency, this thesis (i) develops a scheme to integrate fast semiconductor switches within the current available Matrix Converter topologies, i.e., MOSFET-based Matrix Converter, and (ii) develops a new modulation strategy for the Matrix Converter. This Matrix Converter and the new modulation strategy enables the operation of the converter at a switching-frequency of 40kHz. To provide a reliable source of energy, this thesis also develops a new methodology for robust control of Matrix Converter. To verify the performance of the proposed MOSFET-based Matrix Converter, modulation strategy, and control design methodology, various simulation and experimental results are presented. The experimental results are obtained under operating condition present in an aircraft. The experimental results verify the proposed Matrix Converter provides a reliable power conversion in an aircraft under extreme operating conditions. The results prove the superiority of the proposed Matrix Converter technology for ac to ac power conversion regarding the existing technologies of Matrix Converters.

Comparison of four DNA extraction methods for the detection of Mycobacterium leprae from Ziehl-Neelsen-stained microscopic slides.

PubMed

Ruiz-Fuentes, Jenny Laura; Díaz, Alexis; Entenza, Anayma Elena; Frión, Yahima; Suárez, Odelaisy; Torres, Pedro; de Armas, Yaxsier; Acosta, Lucrecia

2015-12-01

The diagnosis of leprosy has been a challenge due to the low sensibility of the conventional methods and the impossibility of culturing the causative organism. In this study, four methods for Mycobacterium leprae nucleic-acid extraction from Ziehl-Neelsen-stained slides (ZNS slides) were compared: Phenol/chloroform, Chelex 100 resin, and two commercial kits (Wizard Genomic DNA Purification Kit and QIAamp DNA Mini Kit). DNA was extracted from four groups of slides: a high-codification-slide group (bacteriological index [BI]⩾4), a low-codification-slide group (BI=1), a negative-slide group (BI=0), and a negative-control-slide group (BI=0). Quality DNA was evidenced by the amplification of specific repetitive element present in M. leprae genomic DNA (RLEP) using a nested polymerase chain reaction. This is the first report comparing four different extraction methods for obtaining M. leprae DNA from ZNS slides in Cuban patients, and applied in molecular diagnosis. Good-quality DNA and positive amplification were detected in the high-codification-slide group with the four methods, while from the low-codification-slide group only the QIAGEN and phenol-chloroform methods obtained amplification of M. leprae. In the negative-slide group, only the QIAGEN method was able to obtain DNA with sufficient quality for positive amplification of the RLEP region. No amplification was observed in the negative-control-slide group by any method. Patients with ZNS negative slides can still transmit the infection, and molecular methods can help identify and treat them, interrupting the chain of transmission and preventing the onset of disabilities. The ZNS slides can be sent easily to reference laboratories for later molecular analysis that can be useful not only to improve the diagnosis, but also for the application of other molecular techniques. Copyright © 2015 Asian-African Society for Mycobacteriology. Published by Elsevier Ltd. All rights reserved.

Evaluation of the friction force generated by monocristalyne and policristalyne ceramic brackets in sliding mechanics.

PubMed

Pimentel, Roberta Ferreira; de Oliveira, Roberto Sotto Maior Fortes; Chaves, Maria das Graças Afonso Miranda; Elias, Carlos Nelson; Gravina, Marco Abdo

2013-01-01

To evaluate and compare "in vitro" the maximum friction force generated by three types of esthetic brackets, two types of polycrystalline conventional ceramic brackets (20/40 and InVu) and one type of sapphire monocrystalline bracket (Radiance) in dry and artificial saliva wet settings. Also, to evaluate the influence exerted by artificial saliva on the friction forces of those brackets. Tests were performed in dry and artificial saliva wet setting (Oral Balance) by using an EMIC DL 10000 testing machine, simulating a 2 mm slide of 0.019 x 0.025-in rectangular stainless steel wires over the pre-angulated and pre-torqued (right superior canine, Roth prescription, slot 0.022 x 0.030-in) brackets (n = 18 for each bracket). In order to compare groups in dry and wet settings, the ANOVA was used. For comparisons related to the dry versus wet setting, the student t test was used for each group. The results showed that in the absence of saliva the Radiance monocrystalline brackets showed the highest friction coefficients, followed by the 20/40 and the InVu polycrystalline brackets. In tests with artificial saliva, the Radiance and the 20/40 brackets had statistically similar friction coefficients and both were greater than that presented by the InVu brackets. The artificial saliva did not change the maximum friction force of the Radiance brackets, but, for the others (20/40 and InVu), an increase of friction was observed in its presence. The InVu brackets showed, in the absence and in the presence of saliva, the lowest friction coefficient.

Single-Event Transient Testing of the Crane Aerospace and Electronics SMHF2812D Dual DC-DC Converter

NASA Technical Reports Server (NTRS)

Casey, Megan

2015-01-01

The purpose of this testing was to characterize the Crane Aerospace & Electronics (Crane) Interpoint SMHF2812D for single-event transient (SET) susceptibility. These data shall be used for flight lot evaluation, as well as qualification by similarity of the SMHF family of converters, all of which use the same active components.

Design of Phoneme MIDI Codes Using the MIDI Encoding Tool “Auto-F” and Realizing Voice Synthesizing Functions Based on Musical Sounds

NASA Astrophysics Data System (ADS)

Modegi, Toshio

Using our previously developed audio to MIDI code converter tool “Auto-F”, from given vocal acoustic signals we can create MIDI data, which enable to playback the voice-like signals with a standard MIDI synthesizer. Applying this tool, we are constructing a MIDI database, which consists of previously converted simple harmonic structured MIDI codes from a set of 71 Japanese male and female syllable recorded signals. And we are developing a novel voice synthesizing system based on harmonically synthesizing musical sounds, which can generate MIDI data and playback voice signals with a MIDI synthesizer by giving Japanese plain (kana) texts, referring to the syllable MIDI code database. In this paper, we propose an improved MIDI converter tool, which can produce temporally higher-resolution MIDI codes. Then we propose an algorithm separating a set of 20 consonant and vowel phoneme MIDI codes from 71 syllable MIDI converted codes in order to construct a voice synthesizing system. And, we present the evaluation results of voice synthesizing quality between these separated phoneme MIDI codes and their original syllable MIDI codes by our developed 4-syllable word listening tests.

Control Strategies for the DAB Based PV Interface System

PubMed Central

El-Helw, Hadi M.; Al-Hasheem, Mohamed; Marei, Mostafa I.

2016-01-01

This paper presents an interface system based on the Dual Active Bridge (DAB) converter for Photovoltaic (PV) arrays. Two control strategies are proposed for the DAB converter to harvest the maximum power from the PV array. The first strategy is based on a simple PI controller to regulate the terminal PV voltage through the phase shift angle of the DAB converter. The Perturb and Observe (P&O) Maximum Power Point Tracking (MPPT) technique is utilized to set the reference of the PV terminal voltage. The second strategy presented in this paper employs the Artificial Neural Network (ANN) to directly set the phase shift angle of the DAB converter that results in harvesting maximum power. This feed-forward strategy overcomes the stability issues of the feedback strategy. The proposed PV interface systems are modeled and simulated using MATLAB/SIMULINK and the EMTDC/PSCAD software packages. The simulation results reveal accurate and fast response of the proposed systems. The dynamic performance of the proposed feed-forward strategy outdoes that of the feedback strategy in terms of accuracy and response time. Moreover, an experimental prototype is built to test and validate the proposed PV interface system. PMID:27560138

Quantitative analysis of the text and graphic content in ophthalmic slide presentations.

PubMed

Ing, Edsel; Celo, Erdit; Ing, Royce; Weisbrod, Lawrence; Ing, Mercedes

2017-04-01

To determine the characteristics of ophthalmic digital slide presentations. Retrospective quantitative analysis. Slide presentations from a 2015 Canadian primary eye care conference were analyzed for their duration, character and word count, font size, words per minute (wpm), lines per slide, words per slide, slides per minute (spm), text density product (wpm × spm), proportion of graphic content, and Flesch Reading Ease (FRE) score using Microsoft PowerPoint and Word. The median audience evaluation score for the lectures was used to dichotomize the higher scoring lectures (HSL) from the lower scoring lectures (LSL). A priori we hypothesized that there would be a difference in the wpm, spm, text density product, and FRE score between HSL and LSL. Wilcoxon rank-sum tests with Bonferroni correction were utilized. The 17 lectures had medians of 2.5 spm, 20.3 words per slide, 5.0 lines per slide, 28-point sans serif font, 36% graphic content, and text density product of 136.4 words × slides/minute 2 . Although not statistically significant, the HSL had more wpm, fewer words per slide, more graphics per slide, greater text density, and higher FRE score than LSL. There was a statistically significant difference in the spm of the HSL (3.1 ± 1.0) versus the LSL (2.2 ± 1.0) at p = 0.0124. All presenters showed more than 1 slide per minute. The HSL showed more spm than the LSL. The descriptive statistics from this study may aid in the preparation of slides used for teaching and conferences. Copyright © 2017 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

Automated single-slide staining device

NASA Technical Reports Server (NTRS)

Wilkins, J. R.; Mills, S. M. (Inventor)

1977-01-01

A simple apparatus and method is disclosed for making individual single Gram stains on bacteria inoculated slides to assist in classifying bacteria in the laboratory as Gram-positive or Gram-negative. The apparatus involves positioning a single inoculated slide in a stationary position and thereafter automatically and sequentially flooding the slide with increments of a primary stain, a mordant, a decolorizer, a counterstain and a wash solution in a sequential manner without the individual lab technician touching the slide and with minimum danger of contamination thereof from other slides.

Omniview motionless camera orientation system

NASA Technical Reports Server (NTRS)

Martin, H. Lee (Inventor); Kuban, Daniel P. (Inventor); Zimmermann, Steven D. (Inventor); Busko, Nicholas (Inventor)

2010-01-01

An apparatus and method is provided for converting digital images for use in an imaging system. The apparatus includes a data memory which stores digital data representing an image having a circular or spherical field of view such as an image captured by a fish-eye lens, a control input for receiving a signal for selecting a portion of the image, and a converter responsive to the control input for converting digital data corresponding to the selected portion into digital data representing a planar image for subsequent display. Various methods include the steps of storing digital data representing an image having a circular or spherical field of view, selecting a portion of the image, and converting the stored digital data corresponding to the selected portion into digital data representing a planar image for subsequent display. In various embodiments, the data converter and data conversion step may use an orthogonal set of transformation algorithms.

Single Event Effects and Total Dose Testing of the Intersil ISL 70003SEH Integrated Point of Load Converter

NASA Astrophysics Data System (ADS)

van Vonno, N. W.; White, J. D.; Pearce, L. G.; Thomson, E. J.; Gill, J. S.; Mansilla, O. E.

2014-08-01

Single-event transient (SET) phenomena in power management applications has evolved into a key issue, particularly in point of load (POL) buck regulators, as the loads driven by these devices are sensitive to even short-term overvoltage conditions. We preface this paper by a discussion of earlier destructive and nondestructive SEE testing of Intersil integrated point of load regulators, with emphasis on SET phenomena and some of the lessons learned in this work. We then report recent results of SET and destructive SEE testing of the ISL70003SEH POL converter, together with a brief discussion of the part's electrical and radiation hardness specifications. We conclude with a brief overview of low and high dose rate total dose testing of the part.

On the numerical modeling of sliding beams: A comparison of different approaches

NASA Astrophysics Data System (ADS)

Steinbrecher, Ivo; Humer, Alexander; Vu-Quoc, Loc

2017-11-01

The transient analysis of sliding beams represents a challenging problem of structural mechanics. Typically, the sliding motion superimposed by large flexible deformation requires numerical methods as, e.g., finite elements, to obtain approximate solutions. By means of the classical sliding spaghetti problem, the present paper provides a guideline to the numerical modeling with conventional finite element codes. For this purpose, two approaches, one using solid elements and one using beam elements, respectively, are employed in the analysis, and the characteristics of each approach are addressed. The contact formulation realizing the interaction of the beam with its support demands particular attention in the context of sliding structures. Additionally, the paper employs the sliding-beam formulation as a third approach, which avoids the numerical difficulties caused by the large sliding motion through a suitable coordinate transformation. The present paper briefly outlines the theoretical fundamentals of the respective approaches for the modeling of sliding structures and gives a detailed comparison by means of the sliding spaghetti serving as a representative example. The specific advantages and limitations of the different approaches with regard to accuracy and computational efficiency are discussed in detail. Through the comparison, the sliding-beam formulation, which proves as an effective approach for the modeling, can be validated for the general problem of a sliding structure subjected to large deformation.

Experimental study on bubble dynamics and wall heat transfer arising from a single nucleation site at subcooled flow boiling conditions – Part 2: Data analysis on sliding bubble characteristics and associated wall heat transfer

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

Yooa, Junsoo; Estrada-Perez, Carlos E.; Hassan, Yassin A.

In this second of two companion papers presents an analysis of sliding bubble and wall heat transfer parameters measured during subcooled boiling in a square, vertical, upward flow channel. Bubbles were generated only from a single nucleation site for better observation of both the sliding bubbles’ characteristics and their impact on wall heat transfer through optical measurement techniques. Specific interests include: (i) bubbles departure and subsequent growth while sliding, (ii) bubbles release frequency, (iii) coalescence of sliding bubbles, (iv) sliding bubbles velocity, (v) bubbles size distribution and (vi) wall heat transfer influenced by sliding bubbles. Our results showed that slidingmore » bubbles involve two distinct growth behaviors: (i) at low mass fluxes, sliding bubbles grew fast near the nucleation site, subsequently shrank, and then grew again, (ii) as mass flux increased, however, sliding bubbles grew more steadily. The bubbles originating from the single nucleation site coalesced frequently while sliding, which showed close relation with bubbles release frequency. The sliding bubble velocity near the nucleation site consistently decreased by increasing mass flux, while the observation often became reversed as the bubbles slid downstream due to the effect of interfacial drag. The sliding bubbles moved faster than the local liquid (i.e., ur<0) at low mass flux conditions, but it became reversed as the mass flux increased. The size distribution of sliding bubbles followed Gaussian distribution well both near and far from the nucleation site. The standard deviation of bubble size varied insignificantly through sliding compared to the changes in mean bubble size. Lastly, the sliding bubbles enhanced the wall heat transfer and the effect became more noticeable as inlet subcooling/mass flux decreased or wall heat flux increased. Particularly, the sliding bubble characteristics such as bubble growth behavior observed near the nucleation site played a dominant role in determining the ultimate level of wall heat transfer enhancement within the test channel.« less

Experimental study on bubble dynamics and wall heat transfer arising from a single nucleation site at subcooled flow boiling conditions – Part 2: Data analysis on sliding bubble characteristics and associated wall heat transfer

DOE PAGES

Yooa, Junsoo; Estrada-Perez, Carlos E.; Hassan, Yassin A.

2016-04-28

In this second of two companion papers presents an analysis of sliding bubble and wall heat transfer parameters measured during subcooled boiling in a square, vertical, upward flow channel. Bubbles were generated only from a single nucleation site for better observation of both the sliding bubbles’ characteristics and their impact on wall heat transfer through optical measurement techniques. Specific interests include: (i) bubbles departure and subsequent growth while sliding, (ii) bubbles release frequency, (iii) coalescence of sliding bubbles, (iv) sliding bubbles velocity, (v) bubbles size distribution and (vi) wall heat transfer influenced by sliding bubbles. Our results showed that slidingmore » bubbles involve two distinct growth behaviors: (i) at low mass fluxes, sliding bubbles grew fast near the nucleation site, subsequently shrank, and then grew again, (ii) as mass flux increased, however, sliding bubbles grew more steadily. The bubbles originating from the single nucleation site coalesced frequently while sliding, which showed close relation with bubbles release frequency. The sliding bubble velocity near the nucleation site consistently decreased by increasing mass flux, while the observation often became reversed as the bubbles slid downstream due to the effect of interfacial drag. The sliding bubbles moved faster than the local liquid (i.e., ur<0) at low mass flux conditions, but it became reversed as the mass flux increased. The size distribution of sliding bubbles followed Gaussian distribution well both near and far from the nucleation site. The standard deviation of bubble size varied insignificantly through sliding compared to the changes in mean bubble size. Lastly, the sliding bubbles enhanced the wall heat transfer and the effect became more noticeable as inlet subcooling/mass flux decreased or wall heat flux increased. Particularly, the sliding bubble characteristics such as bubble growth behavior observed near the nucleation site played a dominant role in determining the ultimate level of wall heat transfer enhancement within the test channel.« less

The Load and Time Dependence of Chemical Bonding-Induced Frictional Ageing of Silica at the Nanoscale

NASA Astrophysics Data System (ADS)

Tian, K.; Gosvami, N. N.; Goldsby, D. L.; Carpick, R. W.

2015-12-01

Rate and state friction (RSF) laws are empirical relationships that describe the frictional behavior of rocks and other materials in experiments, and reproduce a variety of observed natural behavior when employed in earthquake models. A pervasive observation from rock friction experiments is the linear increase of static friction with the log of contact time, or 'ageing'. Ageing is usually attributed to an increase in real area of contact associated with asperity creep. However, recent atomic force microscopy (AFM) experiments demonstrate that ageing of nanoscale silica-silica contacts is due to progressive formation of interfacial chemical bonds in the absence of plastic deformation, in a manner consistent with the multi-contact ageing behavior of rocks [Li et al., 2011]. To further investigate chemical bonding-induced ageing, we explored the influence of normal load (and thus contact normal stress) and contact time on ageing. Experiments that mimic slide-hold-slide rock friction experiments were conducted in the AFM for contact loads and hold times ranging from 23 to 393 nN and 0.1 to 100 s, respectively, all in humid air (~50% RH) at room temperature. Experiments were conducted by sequentially sliding the AFM tip on the sample at a velocity V of 0.5 μm/s, setting V to zero and holding the tip stationary for a given time, and finally resuming sliding at 0.5 μm/s to yield a peak value of friction followed by a drop to the sliding friction value. Chemical bonding-induced ageing, as measured by the peak friction minus the sliding friction, increases approximately linearly with the product of normal load and the log of the hold time. Theoretical studies of the roles of reaction energy barriers in nanoscale ageing indicate that frictional ageing depends on the total number of reaction sites and the hold time [Liu & Szlufarska, 2012]. We combine chemical kinetics analyses with contact mechanics models to explain our results, and develop a new approach for curve fitting ageing vs. load data which shows that the friction drop data points all fall on a master curve. The analysis yields physically reasonable values for the activation energy and activation volume of the chemical bonding process. Our study provides a basis to hypothesize that the kinetic processes in chemical bonding-induced ageing do not depend strongly on normal load.

Green mosses date the Storegga tsunami to the chilliest decades of the 8.2 ka cold event

NASA Astrophysics Data System (ADS)

Bondevik, Stein; Stormo, Svein Kristian; Skjerdal, Gudrun

2012-06-01

Chlorophyll in dead plants ordinarily decomposes completely before permanent burial through exposure to light, water and oxygen. Here we describe 8000-year-old terrestrial mosses that retain several percent of its original chlorophyll. The mosses were ripped of the land surface, carried 50-100 m off the Norwegian coast of the time, and deposited in depressions on the sea floor by the Storegga tsunami. A little of the chlorophyll survived because, within hours after entraining it, the tsunami buried the mosses in shell-rich sediments. These sediments preserved the chlorophyll by keeping out light and oxygen, and by keeping the pH above 7—three factors known to favour chlorophyll's stability. Because the green mosses were buried alive, their radiocarbon clock started ticking within hours after the Storegga Slide had set off the tsunami. Radiocarbon measurement of the mosses therefore give slide ages of uncommon geological precision, and these, together with a sequence of ages above and below the boundary, date the Storegga Slide to the chilliest decades of the 8.2 ka cold event at 8120-8175 years before AD 1950. North Atlantic coastal- and fjord- climatic records claimed to show evidence of the 8.2 cold event should be carefully examined for possible contamination and disturbance from the Storegga tsunami.

Design and analysis of adaptive Super-Twisting sliding mode control for a microgyroscope.

PubMed

Feng, Zhilin; Fei, Juntao

2018-01-01

This paper proposes a novel adaptive Super-Twisting sliding mode control for a microgyroscope under unknown model uncertainties and external disturbances. In order to improve the convergence rate of reaching the sliding surface and the accuracy of regulating and trajectory tracking, a high order Super-Twisting sliding mode control strategy is employed, which not only can combine the advantages of the traditional sliding mode control with the Super-Twisting sliding mode control, but also guarantee that the designed control system can reach the sliding surface and equilibrium point in a shorter finite time from any initial state and avoid chattering problems. In consideration of unknown parameters of micro gyroscope system, an adaptive algorithm based on Lyapunov stability theory is designed to estimate the unknown parameters and angular velocity of microgyroscope. Finally, the effectiveness of the proposed scheme is demonstrated by simulation results. The comparative study between adaptive Super-Twisting sliding mode control and conventional sliding mode control demonstrate the superiority of the proposed method.

Analysis and Synthesis of Memory-Based Fuzzy Sliding Mode Controllers.

PubMed

Zhang, Jinhui; Lin, Yujuan; Feng, Gang

2015-12-01

This paper addresses the sliding mode control problem for a class of Takagi-Sugeno fuzzy systems with matched uncertainties. Different from the conventional memoryless sliding surface, a memory-based sliding surface is proposed which consists of not only the current state but also the delayed state. Both robust and adaptive fuzzy sliding mode controllers are designed based on the proposed memory-based sliding surface. It is shown that the sliding surface can be reached and the closed-loop control system is asymptotically stable. Furthermore, to reduce the chattering, some continuous sliding mode controllers are also presented. Finally, the ball and beam system is used to illustrate the advantages and effectiveness of the proposed approaches. It can be seen that, with the proposed control approaches, not only can the stability be guaranteed, but also its transient performance can be improved significantly.

FORMATOMATIC: a program for converting diploid allelic data between common formats for population genetic analysis.

PubMed

Manoukis, Nicholas C

2007-07-01

There has been a great increase in both the number of population genetic analysis programs and the size of data sets being studied with them. Since the file formats required by the most popular and useful programs are variable, automated reformatting or conversion between them is desirable. formatomatic is an easy to use program that can read allelic data files in genepop, raw (csv) or convert formats and create data files in nine formats: raw (csv), arlequin, genepop, immanc/bayesass +, migrate, newhybrids, msvar, baps and structure. Use of formatomatic should greatly reduce time spent reformatting data sets and avoid unnecessary errors.

System and Method for Providing a Real Time Audible Message to a Pilot

NASA Technical Reports Server (NTRS)

Johnson, Walter W. (Inventor); Lachter, Joel B. (Inventor); Koteskey, Robert W. (Inventor); Battiste, Vernol (Inventor)

2016-01-01

A system and method for providing information to a crew of the aircraft while in-flight. The system includes a module having: a receiver for receiving a message while in-flight; a filter having a set of screening parameters and operative to filter the message based on the set of screening parameters; and a converter for converting the message into an audible message. The message includes a pilot report having at least one of weather information, separation information, congestion information, flight deviation information and destination information. The message is sent to the aircraft by another aircraft or an air traffic controller.

Heat Source/Sink in a Magneto-Hydrodynamic Non-Newtonian Fluid Flow in a Porous Medium: Dual Solutions

PubMed Central

Hayat, Tasawar; Awais, Muhammad; Imtiaz, Amna

2016-01-01

This communication deals with the properties of heat source/sink in a magneto-hydrodynamic flow of a non-Newtonian fluid immersed in a porous medium. Shrinking phenomenon along with the permeability of the wall is considered. Mathematical modelling is performed to convert the considered physical process into set of coupled nonlinear mathematical equations. Suitable transformations are invoked to convert the set of partial differential equations into nonlinear ordinary differential equations which are tackled numerically for the solution computations. It is noted that dual solutions for various physical parameters exist which are analyzed in detail. PMID:27598314

An Automatic Speed Control for Wind Tunnels

NASA Technical Reports Server (NTRS)

Zahm, A F

1928-01-01

Described here is an automatic control that has been used in several forms in wind tunnels at the Washington Navy Yard. The form now in use with the 8-foot tunnel at the Navy Yard is considered here. Details of the design and operation of the automatic control system are given. Leads from a Pitot tube are joined to an inverted cup manometer located above a rheostat. When the sliding weight of this instrument is set to a given notch, say for 40 m.p.h, the beam tip vibrates between two electric contacts that feed the little motor. Thus, when the wind is too strong or too weak, the motor automatically throws the rheostat slide forward and backward. If it failed to function well, the operator would notice the effect on his meniscus, and would operate the hand control by merely pressing the switch.

Rotary fast tool servo system and methods

DOEpatents

Montesanti, Richard C.; Trumper, David L.

2007-10-02

A high bandwidth rotary fast tool servo provides tool motion in a direction nominally parallel to the surface-normal of a workpiece at the point of contact between the cutting tool and workpiece. Three or more flexure blades having all ends fixed are used to form an axis of rotation for a swing arm that carries a cutting tool at a set radius from the axis of rotation. An actuator rotates a swing arm assembly such that a cutting tool is moved in and away from the lathe-mounted, rotating workpiece in a rapid and controlled manner in order to machine the workpiece. A pair of position sensors provides rotation and position information for a swing arm to a control system. A control system commands and coordinates motion of the fast tool servo with the motion of a spindle, rotating table, cross-feed slide, and in-feed slide of a precision lathe.

Rotary fast tool servo system and methods

DOEpatents

Montesanti, Richard C [Cambridge, MA; Trumper, David L [Plaistow, NH; Kirtley, Jr., James L.

2009-08-18

A high bandwidth rotary fast tool servo provides tool motion in a direction nominally parallel to the surface-normal of a workpiece at the point of contact between the cutting tool and workpiece. Three or more flexure blades having all ends fixed are used to form an axis of rotation for a swing arm that carries a cutting tool at a set radius from the axis of rotation. An actuator rotates a swing arm assembly such that a cutting tool is moved in and away from the lathe-mounted, rotating workpiece in a rapid and controlled manner in order to machine the workpiece. One or more position sensors provides rotation and position information for a swing arm to a control system. A control system commands and coordinates motion of the fast tool servo with the motion of a spindle, rotating table, cross-feed slide, and in-feed slide of a precision lathe.

The contribution of MIB 1 in the accurate grading of vulvar intraepithelial neoplasia.

PubMed

van Beurden, M; de Craen, A J; de Vet, H C; Blaauwgeers, J L; Drillenburg, P; Gallee, M P; de Kraker, N W; Lammes, F B; ten Kate, F J

1999-11-01

To determine the interobserver variation in scoring presence and grade of vulvar intraepithelial neoplasia (VIN) in haematoxylin/eosin (H/E) slides, MIB 1 slides, and the combined use of H/E and MIB 1 slides. 10 slides were stained with H/E and MIB 1 with each of the following diagnoses: normal vulvar skin, VIN 1, VIN 2, and VIN 3. Six observers first scored the H/E slides separately from the MIB 1 slides and second the combined H/E and MIB 1 slides. Unweighted group kappa for MIB 1 was 0.62 and the weighted group kappa was 0.91. This was significantly better than the unweighted group kappa for H/E slides (0.47, p = 0.023) as well as the weighted group kappa for H/E slides (0.82, p = 0.014). There was no improvement by the combined use of H/E and MIB 1 slides. VIN 2 is far less confused with VIN 3 in the combined use of H/E and MIB 1 slides (9%) than in H/E slides (38%) (p = 0.007). There is a tendency to grade VIN in a two tailed grading system rather than a three tailed grading system, which became more apparent with the combined use of H/E and MIB 1 slides. The interobserver variation with sole use of MIB 1 is better than with the use of H/E stain in VIN. The use of MIB 1 in grading VIN diminishes confusion between VIN 2 and VIN 3 fourfold. A two tailed grading system for VIN seems already to work in daily practice.

The contribution of MIB 1 in the accurate grading of vulvar intraepithelial neoplasia.

PubMed Central

van Beurden, M; de Craen, A J; de Vet, H C; Blaauwgeers, J L; Drillenburg, P; Gallee, M P; de Kraker, N W; Lammes, F B; ten Kate, F J

1999-01-01

AIM: To determine the interobserver variation in scoring presence and grade of vulvar intraepithelial neoplasia (VIN) in haematoxylin/eosin (H/E) slides, MIB 1 slides, and the combined use of H/E and MIB 1 slides. METHODS: 10 slides were stained with H/E and MIB 1 with each of the following diagnoses: normal vulvar skin, VIN 1, VIN 2, and VIN 3. Six observers first scored the H/E slides separately from the MIB 1 slides and second the combined H/E and MIB 1 slides. RESULTS: Unweighted group kappa for MIB 1 was 0.62 and the weighted group kappa was 0.91. This was significantly better than the unweighted group kappa for H/E slides (0.47, p = 0.023) as well as the weighted group kappa for H/E slides (0.82, p = 0.014). There was no improvement by the combined use of H/E and MIB 1 slides. VIN 2 is far less confused with VIN 3 in the combined use of H/E and MIB 1 slides (9%) than in H/E slides (38%) (p = 0.007). There is a tendency to grade VIN in a two tailed grading system rather than a three tailed grading system, which became more apparent with the combined use of H/E and MIB 1 slides. CONCLUSIONS: The interobserver variation with sole use of MIB 1 is better than with the use of H/E stain in VIN. The use of MIB 1 in grading VIN diminishes confusion between VIN 2 and VIN 3 fourfold. A two tailed grading system for VIN seems already to work in daily practice. Images PMID:10690171

Making data matter: Voxel printing for the digital fabrication of data across scales and domains.

PubMed

Bader, Christoph; Kolb, Dominik; Weaver, James C; Sharma, Sunanda; Hosny, Ahmed; Costa, João; Oxman, Neri

2018-05-01

We present a multimaterial voxel-printing method that enables the physical visualization of data sets commonly associated with scientific imaging. Leveraging voxel-based control of multimaterial three-dimensional (3D) printing, our method enables additive manufacturing of discontinuous data types such as point cloud data, curve and graph data, image-based data, and volumetric data. By converting data sets into dithered material deposition descriptions, through modifications to rasterization processes, we demonstrate that data sets frequently visualized on screen can be converted into physical, materially heterogeneous objects. Our approach alleviates the need to postprocess data sets to boundary representations, preventing alteration of data and loss of information in the produced physicalizations. Therefore, it bridges the gap between digital information representation and physical material composition. We evaluate the visual characteristics and features of our method, assess its relevance and applicability in the production of physical visualizations, and detail the conversion of data sets for multimaterial 3D printing. We conclude with exemplary 3D-printed data sets produced by our method pointing toward potential applications across scales, disciplines, and problem domains.

The Impact of Pecha Kucha Presentations in the Assessment of a Translation Studies Unit at the University of Western Australia

ERIC Educational Resources Information Center

Colombi, Anna Gadd

2017-01-01

Results of a case study on the implementation of Pecha Kucha presentations undertaken at The University of Western Australia in 2015 are presented and discussed here. Pecha Kucha, a fast-paced presentation format consisting of 20 slides set to proceed automatically every 20 seconds, was used in the assessment of the unit "Translation…

One Sound Is Worth a Thousand Words: Using and Understanding Audio Files

ERIC Educational Resources Information Center

Frantiska, Joseph J., Jr.

2008-01-01

In the past few years, there has been an increased emphasis for teachers to become more adept at multimedia-based skills. Whether it's creating PowerPoint[R] slides, MPEG movies, image files, or a host of other tasks, today's K-12 teacher needs to have an appropriate level of expertise in multimedia development. One aspect of this skill set that…

Evaluation of an enclosed ultraviolet-C radiation device for decontamination of mobile handheld devices.

PubMed

Mathew, J Itty; Cadnum, Jennifer L; Sankar, Thriveen; Jencson, Annette L; Kundrapu, Sirisha; Donskey, Curtis J

2016-06-01

Mobile handheld devices used in health care settings may become contaminated with health care-associated pathogens. We demonstrated that an enclosed ultraviolet-C radiation device was effective in rapidly reducing methicillin-resistant Staphylococcus aureus, and with longer exposure times, Clostridium difficile spores, on glass slides and reducing contamination on in-use mobile handheld devices. Published by Elsevier Inc.

Evolution of a visual impact model to evaluate nuclear plant siting and design option

Treesearch

Brian A. Gray; John Ady; Grant R. Jones

1979-01-01

The development of a visual impact method- elegy is reviewed from first concepts (1973) to application.3/ The method can be used to train evaluators to use explicit criteria (vividness, intactness and unity) to assess change in a setting's visual quality as the result of construction of a nuclear facility, or any other visible alteration. Slides of "before...

Using First-Person Perspective Filming Techniques for a Chemistry Laboratory Demonstration to Facilitate a Flipped Pre-Lab

ERIC Educational Resources Information Center

Fung, Fun Man

2015-01-01

The current model of flipped classroom ensures that learning is not being restricted to the brick and mortar setting. Lessons can be conducted anywhere, anytime, as long as there is a good internet connection. Most of the flipped classroom and e-lectures are videos recording PowerPoint slides with a human voice as the audio instruction. In…

Moving Forward or Sliding Backward: The Evolution of Charter School Policies in Michigan and the District of Columbia

ERIC Educational Resources Information Center

Lacireno-Paquet, Natalie; Holyoke, Thomas T.

2007-01-01

What is the fate of charter school policy in the American states? The authors argue that dramatic new policies brought about by a radical reconfiguration of interests and politics are frequently short lived, though new policies are rarely erased; instead, they reach a compromise between competing sets of interests. The authors test this notion in…

Transition of Research into Medical Practice

NASA Technical Reports Server (NTRS)

Polk, James D.; Johnson-Throop, Kathy A.

2010-01-01

This slide presentation reviews the process of transforming medical research into practical medicine for astronauts and for every day people. Several examples of medical practices that started in space medical research and then were proved useful in other settings: Actigraphy, bone density scanning, the use of Potassium Citrate as a countermeasure used to lessen the risk of kidney stone formation, and ultrasound uses in remote and telemedicine,

Field Enhancement Properties of Nanotubes in a Field Emission Set-Up

NASA Technical Reports Server (NTRS)

Adessi, Ch.; Devel, M.

2001-01-01

This slide presentation reviews the mechanisms of emission of nanotubes. The field enhancement properties of carbon nanotubes, involved in the emission of electrons, is investigated theoretically for various single-wall (SWNT) and multi-wall nanotubes (MWNT). The presentation points out big differences between (n,0) and (n,n) nanotubes, and propose phenomenological laws for the variations of the enhancement factor with length and diameter

Graduate School and Fellowship Discussion

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

Farrar, Charles Reed

This was a presentation presented for the Los Alamos Dynamics Summer School. This is a set of slides about how to prepare for college, specifically graduate school. It gives instructions for succeeding and getting into a good school with financial aid through assistantships and scholarships, specifically applying to engineering backgrounds. Also, there are tips given for applying for fellowships and concludes with some general recommendations for graduate school.

Office of the CIO: Setting the Vision

NASA Technical Reports Server (NTRS)

Rinaldi, James J.

2006-01-01

This slide presentation reviews the vision of the Office of JPL's Chief Information Officer for future of information technology (IT) at JPL. This includes a strong working relation with industry to provide cost efficient and effective IT services. This includes a vision of taking desktop to the next level and the process to achieve it and ensuring that JPL becomes a world class IT provider.

Beyond the New Architectures - Enabling Rapid System Configurations

NASA Technical Reports Server (NTRS)

Smith, Dan

2009-01-01

This presentation slide document reviews the attempts to integrate systems and create common standards for missions. A primary example is telemetry and command sets for satellites. The XML Telemetric and Command Exchange (XTCE) exists, but this is not easy to implement. There is a need for a new standard. The document proposes a method to achieve the standard, and the benefits of using a new standard,

WTP Pretreatment Facility Potential Design Deficiencies--Sliding Bed and Sliding Bed Erosion Assessment

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

Hansen, E. K.

2015-05-06

This assessment is based on readily available literature and discusses both Newtonian and non-Newtonian slurries with respect to sliding beds and erosion due to sliding beds. This report does not quantify the size of the sliding beds or erosion rates due to sliding beds, but only assesses if they could be present. This assessment addresses process pipelines in the Pretreatment (PT) facility and the high level waste (HLW) transfer lines leaving the PT facility to the HLW vitrification facility concentrate receipt vessel.

Numerical Modelling of Tsunami Generated by Deformable Submarine Slides: Parameterisation of Slide Dynamics for Coupling to Tsunami Propagation Model

NASA Astrophysics Data System (ADS)

Smith, R. C.; Collins, G. S.; Hill, J.; Piggott, M. D.; Mouradian, S. L.

2015-12-01

Numerical modelling informs risk assessment of tsunami generated by submarine slides; however, for large-scale slides modelling can be complex and computationally challenging. Many previous numerical studies have approximated slides as rigid blocks that moved according to prescribed motion. However, wave characteristics are strongly dependent on the motion of the slide and previous work has recommended that more accurate representation of slide dynamics is needed. We have used the finite-element, adaptive-mesh CFD model Fluidity, to perform multi-material simulations of deformable submarine slide-generated waves at real world scales for a 2D scenario in the Gulf of Mexico. Our high-resolution approach represents slide dynamics with good accuracy, compared to other numerical simulations of this scenario, but precludes tracking of wave propagation over large distances. To enable efficient modelling of further propagation of the waves, we investigate an approach to extract information about the slide evolution from our multi-material simulations in order to drive a single-layer wave propagation model, also using Fluidity, which is much less computationally expensive. The extracted submarine slide geometry and position as a function of time are parameterised using simple polynomial functions. The polynomial functions are used to inform a prescribed velocity boundary condition in a single-layer simulation, mimicking the effect the submarine slide motion has on the water column. The approach is verified by successful comparison of wave generation in the single-layer model with that recorded in the multi-material, multi-layer simulations. We then extend this approach to 3D for further validation of this methodology (using the Gulf of Mexico scenario proposed by Horrillo et al., 2013) and to consider the effect of lateral spreading. This methodology is then used to simulate a series of hypothetical submarine slide events in the Arctic Ocean (based on evidence of historic slides) and examine the hazard posed to the UK coast.

Frictional sliding inclusions

NASA Astrophysics Data System (ADS)

Huang, Jin H.; Furuhashi, R.; Mura, T.

1993-02-01

S OLUTIONS ARE presented in closed form by using an averaging method for inclusions sliding along an interface due to uniform eigenstrains precribed in the inclusions. The associated stress fields are also analytically determined. A parameter s is introduced to indicate the relative magnitude of sliding compared with the extreme cases of perfect bonding and perfect sliding. When the parameter s becomes zero, the present solution coincides with Eshelby's solution which is the perfectly bonded case. In contrast, when the parameter s is unity, the solution agrees with Volterra's solution (M URA and F URUHASHI, 1984, J. appl. Mech.51, 308] for the perfect sliding case. Because of non-uniform elastic fields caused by sliding along the interface, the well-known Eshelby tensor is modified for the sliding inclusions. Moreover, based on the Mori-Tanaka theory (M ORI and T ANAKA, 1973, Acta Metall.21, 571), an overall stress-strain relation is established to characterize the sliding effect on the overall elastic moduli.

SlideJ: An ImageJ plugin for automated processing of whole slide images.

PubMed

Della Mea, Vincenzo; Baroni, Giulia L; Pilutti, David; Di Loreto, Carla

2017-01-01

The digital slide, or Whole Slide Image, is a digital image, acquired with specific scanners, that represents a complete tissue sample or cytological specimen at microscopic level. While Whole Slide image analysis is recognized among the most interesting opportunities, the typical size of such images-up to Gpixels- can be very demanding in terms of memory requirements. Thus, while algorithms and tools for processing and analysis of single microscopic field images are available, Whole Slide images size makes the direct use of such tools prohibitive or impossible. In this work a plugin for ImageJ, named SlideJ, is proposed with the objective to seamlessly extend the application of image analysis algorithms implemented in ImageJ for single microscopic field images to a whole digital slide analysis. The plugin has been complemented by examples of macro in the ImageJ scripting language to demonstrate its use in concrete situations.

Fuzzy fractional order sliding mode controller for nonlinear systems

NASA Astrophysics Data System (ADS)

Delavari, H.; Ghaderi, R.; Ranjbar, A.; Momani, S.

2010-04-01

In this paper, an intelligent robust fractional surface sliding mode control for a nonlinear system is studied. At first a sliding PD surface is designed and then, a fractional form of these networks PDα, is proposed. Fast reaching velocity into the switching hyperplane in the hitting phase and little chattering phenomena in the sliding phase is desired. To reduce the chattering phenomenon in sliding mode control (SMC), a fuzzy logic controller is used to replace the discontinuity in the signum function at the reaching phase in the sliding mode control. For the problem of determining and optimizing the parameters of fuzzy sliding mode controller (FSMC), genetic algorithm (GA) is used. Finally, the performance and the significance of the controlled system two case studies (robot manipulator and coupled tanks) are investigated under variation in system parameters and also in presence of an external disturbance. The simulation results signify performance of genetic-based fuzzy fractional sliding mode controller.

SlideJ: An ImageJ plugin for automated processing of whole slide images

PubMed Central

Baroni, Giulia L.; Pilutti, David; Di Loreto, Carla

2017-01-01

The digital slide, or Whole Slide Image, is a digital image, acquired with specific scanners, that represents a complete tissue sample or cytological specimen at microscopic level. While Whole Slide image analysis is recognized among the most interesting opportunities, the typical size of such images—up to Gpixels- can be very demanding in terms of memory requirements. Thus, while algorithms and tools for processing and analysis of single microscopic field images are available, Whole Slide images size makes the direct use of such tools prohibitive or impossible. In this work a plugin for ImageJ, named SlideJ, is proposed with the objective to seamlessly extend the application of image analysis algorithms implemented in ImageJ for single microscopic field images to a whole digital slide analysis. The plugin has been complemented by examples of macro in the ImageJ scripting language to demonstrate its use in concrete situations. PMID:28683129

A study of the 1963 Vajont landslide zonation by means of Lagrangian block modelling

NASA Astrophysics Data System (ADS)

Zaniboni, Filippo; Ausilia Paparo, Maria; Tinti, Stefano

2017-04-01

The 1963 landslide detaching from Mt. Toc (North-East Italy), that crashing on the underlying Vajont reservoir caused a huge wave that killed over 2000 people, is a well-known event that has been extensively and deeply investigated. Recently, studies appeared in the literature suggesting that the landslide dynamics can be explained in terms of a zonation of the moving mass. In this work, an additional support to the zonation hypothesis is given by focusing on the friction coefficient of the sliding surface, which is one of the chief parameters influencing the slide motion. Numerical simulations of the Vajont slide found in the literature assumed a homogenous value of the friction coefficient. We have systematically investigated a set of heterogeneous configurations. More specifically, we have divided the sliding surface into a number N of zones, and let the corresponding friction coefficient vary in the range 0-0.5. For each configuration we have run the numerical simulation via the Lagrangian block-based code UBO-BLOCK2 and have evaluated the configuration goodness by computing the misfit between the observed and the simulated deposits. The number of simulations required by this approach increases exponentially with the number N of zones. The main finding of this research is that a 4-sector zonation provides the best results in terms of deposit misfit. The zones can be roughly described as west-downhill (WD), west uphill (WU), east downhill (ED) and east uphill (EU). It is found that motion is mainly determined by friction in zones WD and EU, that friction coefficients in zone WD is remarkably smaller than in zone EU and that misfit is rather insensitive to the values of the friction coefficients in zones WU and ED.

Evaluation of laser ablation microtomy for correlative microscopy of hard tissues.

PubMed

Boyde, A

2018-02-27

Laser ablation machining or microtomy (LAM) is a relatively new approach to producing slide mounted sections of translucent materials. We evaluated the method with a variety of problems from the bone, joint and dental tissues fields where we require thin undecalcified and undistorted sections for correlative light microscopy (LM) and backscattered electron scanning electron microscopy (BSE SEM). All samples were embedded in poly-methylmethacrlate (PMMA) and flat block surfaces had been previously studied by BSE-SEM and confocal scanning light microscopy (CSLM). Most were also studied by X-yay microtomography (XMT). The block surface is stuck to a glass slide with cyanoacrylate adhesive. Setting the section thickness and levelling uses inbuilt optical coherence tomographic imaging. Tight focusing of near-infrared laser radiation in the sectioning plane gives extreme intensities causing photodisruption of material at the focal point. The laser beam is moved by a fast scanner to write a cutting line, which is simultaneously moved by an XY positioning unit to create a sectioning plane. The block is thereby released from the slide, leaving the section stuck to the slide. Light, wet polishing on the finest grade (4000 grit) silicon carbide polishing paper is used to remove a 1-2 μm thick damaged layer at the surface of the section. Sections produced by laser cutting are fine in quality and superior to those produced by mechanical cutting and can be thinner than the 'voxel' in most laboratory X-ray microtomography systems. The present extensive pilot studies have shown that it works to produce samples which we can study by both light and electron microscopy. © 2018 The Authors Journal of Microscopy © 2018 Royal Microscopical Society.

Effects of high and low temperatures on development time and mortality of house dust mite eggs.

PubMed

Mahakittikun, Vanna; Boitano, John Joseph; Ninsanit, Prapakorn; Wangapai, Teerapong; Ralukruedej, Kornraphat

2011-12-01

Hatching of Dermatophagoides pteronyssinus eggs was investigated when exposed to temperatures ranging from -70 to +70°C, at varying degrees of humidity (dry and wet heat, direct sunlight) and lengths of time (seven intervals, ranging from 0.5 to 5 h). Exposure to cold was induced using a domestic refrigerator at 4°C, its freezing compartment at -10°C and a deep freezer at -20, -40 and -70°C. For each time interval, there were three slides containing 30 eggs per slide, except for sunlight (five sets of slides). After treatment, all experimental groups were kept on an open work bench for 15 days of observation at ambient room temperature (ca. 22°C) and ca. 75% relative humidity. Control groups with 10 eggs per slide, in triplicate, followed a similar protocol. An egg was considered hatched if an emerging larva was detected from a cracked shell. Results indicated that at 40°C for both dry and wet heat, approximately 80% of all eggs survived. At direct sunlight and dry heat at 50°C, the thermal death point (TDP) occurred at 3 and 5 h, respectively. At 60 and 70°C both wet and dry heat, TDP occurred almost instantaneously. Under cold conditions, only the deep freezer at -70°C was effective in preventing hatching. It may be concluded that exposure to direct sunlight for 3 h, dry/wet heat of 60 and 70°C for a minimum of 30 min, and -70°C prevent egg hatching. This study may have relevance for mite control procedures.

Does fault strengthening in laboratory rock friction experiments really depend primarily upon time and not slip?

NASA Astrophysics Data System (ADS)

Bhattacharya, Pathikrit; Rubin, Allan M.; Beeler, Nicholas M.

2017-08-01

The popular constitutive formulations of rate-and-state friction offer two end-member views on whether friction evolves only with slip (Slip law) or with time even without slip (Aging law). While rate stepping experiments show support for the Slip law, laboratory-observed frictional behavior near-zero slip rates has traditionally been inferred as supporting Aging law style time-dependent healing, in particular, from the slide-hold-slide experiments of Beeler et al. (1994). Using a combination of new analytical results and explicit numerical (Bayesian) inversion, we show instead that the slide-hold-slide data of Beeler et al. (1994) favor slip-dependent state evolution during holds. We show that, while the stiffness-independent rate of growth of peak stress (following reslides) with hold duration is a property shared by both the Aging and (under a more restricted set of parameter combinations) Slip laws, the observed stiffness dependence of the rate of stress relaxation during long holds is incompatible with the Aging law with constant rate-state parameters. The Slip law consistently fits the evolution of the stress minima at the end of the holds well, whether fitting jointly with peak stresses or otherwise. But neither the Aging nor Slip laws fit all the data well when a - b is constrained to values derived from prior velocity steps. We also attempted to fit the evolution of stress peaks and minima with the Kato-Tullis hybrid law and the shear stress-dependent Nagata law, both of which, even with the freedom of an extra parameter, generally reproduced the best Slip law fits to the data.

Optimum design of bridges with superelastic-friction base isolators against near-field earthquakes

NASA Astrophysics Data System (ADS)

Ozbulut, Osman E.; Hurlebaus, Stefan

2010-04-01

The seismic response of a multi-span continuous bridge isolated with novel superelastic-friction base isolator (S-FBI) is investigated under near-field earthquakes. The isolation system consists of a flat steel-Teflon sliding bearing and a superelastic NiTi shape memory alloy (SMA) device. Sliding bearings limit the maximum seismic forces transmitted to the superstructure to a certain value that is a function of friction coefficient of sliding interface. Superelastic SMA device provides restoring capability to the isolation system together with additional damping characteristics. The key design parameters of an S-FBI system are the natural period of the isolated, yielding displacement of SMA device, and the friction coefficient of the sliding bearings. The goal of this study is to obtain optimal values for each design parameter by performing sensitivity analyses of the isolated bridge. First, a three-span continuous bridge is modeled as a two-degrees-of-freedom with S-FBI system. A neuro-fuzzy model is used to capture rate-dependent nonlinear behavior of SMA device. A time-dependent method which employs wavelets to adjust accelerograms to match a target response spectrum with minimum changes on the other characteristics of ground motions is used to generate ground motions used in the simulations. Then, a set of nonlinear time history analyses of the isolated bridge is performed. The variation of the peak response quantities of the isolated bridge is shown as a function of design parameters. Also, the influence of temperature variations on the effectiveness of S-FBI system is evaluated. The results show that the optimum design of the isolated bridge with S-FBI system can be achieved by a judicious specification of design parameters.

Comparing whole slide digital images versus traditional glass slides in the detection of common microscopic features seen in dermatitis

PubMed Central

Vyas, Nikki S.; Markow, Michael; Prieto-Granada, Carlos; Gaudi, Sudeep; Turner, Leslie; Rodriguez-Waitkus, Paul; Messina, Jane L.; Jukic, Drazen M.

2016-01-01

Background: The quality and limitations of digital slides are not fully known. We aimed to estimate intrapathologist discrepancy in detecting specific microscopic features on glass slides and digital slides created by scanning at ×20. Methods: Hematoxylin and eosin and periodic acid–Schiff glass slides were digitized using the Mirax Scan (Carl Zeiss Inc., Germany). Six pathologists assessed 50–71 digital slides. We recorded objective magnification, total time, and detection of the following: Mast cells; eosinophils; plasma cells; pigmented macrophages; melanin in the epidermis; fungal bodies; neutrophils; civatte bodies; parakeratosis; and sebocytes. This process was repeated using the corresponding glass slides after 3 weeks. The diagnosis was not required. Results: The mean time to assess digital slides was 176.77 s and 137.61 s for glass slides (P < 0.001, 99% confidence interval [CI]). The mean objective magnification used to detect features using digital slides was 18.28 and 14.07 for glass slides (P < 0.001, 99.99% CI). Parakeratosis, civatte bodies, pigmented macrophages, melanin in the epidermis, mast cells, eosinophils, plasma cells, and neutrophils, were identified at lower objectives on glass slides (P = 0.023–0.001, 95% CI). Average intraobserver concordance ranged from κ = 0.30 to κ = 0.78. Features with poor to fair average concordance were: Melanin in the epidermis (κ = 0.15–0.58); plasma cells (κ = 0.15–0.49); and neutrophils (κ = 0.12–0.48). Features with moderate average intrapathologist concordance were: parakeratosis (κ = 0.21–0.61); civatte bodies (κ = 0.21–0.71); pigment-laden macrophages (κ = 0.34–0.66); mast cells (κ = 0.29–0.78); and eosinophils (κ = 0.31–0.79). The average intrapathologist concordance was good for sebocytes (κ = 0.51–1.00) and fungal bodies (κ = 0.47–0.76). Conclusions: Telepathology using digital slides scanned at ×20 is sufficient for detection of histopathologic features routinely encountered in dermatitis cases, though less efficient than glass slides. PMID:27563489

An energy-absorbing sliding seat for reducing neck injury risks in rear impact--analysis for prototype built.

PubMed

Zhang, Xiaowei; Zhou, Qing

2016-01-01

This study investigated overall performance of an energy-absorbing sliding seat concept for whiplash neck injury prevention. The sliding seat allows its seat pan to slide backward for some distance under certain restraint force to absorb crash energy in rear impacts. A numerical model that consisted of vehicle interior, seat, seat belt, and BioRID II dummy was built in MADYMO to evaluate whiplash neck injury in rear impact. A parametric study of the effects of sliding seat parameters, including position and cushion stiffness of head restraint, seatback cushion stiffness, recliner characteristics, and especially sliding energy-absorbing (EA) restraint force, on neck injury criteria was conducted in order to compare the effectiveness of the sliding seat concept with that of other existing anti-whiplash mechanisms. Optimal sliding seat design configurations in rear crashes of different severities were obtained. A sliding seat prototype with bending of a steel strip as an EA mechanism was fabricated and tested in a sled test environment to validate the concept. The performance of the sliding seat under frontal and rollover impacts was checked to make sure the sliding mechanism did not result in any negative effects. The protective effect of the sliding seat with EA restraint force is comparable to that of head restraint-based and recliner stiffness-based anti-whiplash mechanisms. EA restraint force levels of 3 kN in rear impacts of low and medium severities and 6 kN in impacts of high severity were obtained from optimization. In frontal collision and rollover, compared to the nonsliding seat, the sliding seat does not result in any negative effects on occupant protection. The sled test results of the sliding seat prototype have shown the effectiveness of the concept for reducing neck injury risks. As a countermeasure, the sliding seat with appropriate restraint forces can significantly reduce whiplash neck injury risk in rear impacts of low, medium, and high severities with no negative effects on other crash load cases.

A method for reducing the sloughing of thick blood films for malaria diagnosis.

PubMed

Norgan, Andrew P; Arguello, Heather E; Sloan, Lynne M; Fernholz, Emily C; Pritt, Bobbi S

2013-07-08

The gold standard for malaria diagnosis is the examination of thick and thin blood films. Thick films contain 10 to 20 times more blood than thin films, correspondingly providing increased sensitivity for malaria screening. A potential complication of thick film preparations is sloughing of the blood droplet from the slide during staining or rinsing, resulting in the loss of sample. In this work, two methods for improving thick film slide adherence ('scratch' (SCM) and 'acetone dip' (ADM) methods) were compared to the 'standard method' (SM) of thick film preparation. Standardized blood droplets from 26 previously examined EDTA whole blood specimens (22 positive and four negative) were concurrently spread on glass slides using the SM, ADM, and SCM. For the SM and ADM prepared slides, the droplet was gently spread to an approximate 22 millimeters in diameter spot on the slide using the edge of a second glass slide. For the SCM, the droplet was spread by carefully grinding (or scratching) it into the slide with the point of a second glass slide. Slides were dried for one hour in a laminar flow hood. For the ADM, slides were dipped once in an acetone filled Coplin jar and allowed to air dry. All slides were then Giemsa-stained and examined in a blinded manner. Adherence was assessed by blinded reviewers. No significant or severe defects were observed for slides prepared with the SCM. In contrast, 8 slides prepared by the ADM and 3 prepared using the SM displayed significant or severe defects. Thick films prepared by the three methods were microscopically indistinguishable and concordant results (positive or negative) were obtained for the three methods. Estimated parasitaemia of the blood samples ranged from 25 to 429,169 parasites/μL of blood. The SCM is an inexpensive, rapid, and simple method that improves the adherence of thick blood films to standard glass slides without altering general slide preparation, microscopic appearance or interpretability. Using the SCM, thick films can be reliably examined less than two hours after sample receipt. This represents a significant diagnostic improvement over protocols requiring extended drying periods.

Optimal second order sliding mode control for nonlinear uncertain systems.

PubMed

Das, Madhulika; Mahanta, Chitralekha

2014-07-01

In this paper, a chattering free optimal second order sliding mode control (OSOSMC) method is proposed to stabilize nonlinear systems affected by uncertainties. The nonlinear optimal control strategy is based on the control Lyapunov function (CLF). For ensuring robustness of the optimal controller in the presence of parametric uncertainty and external disturbances, a sliding mode control scheme is realized by combining an integral and a terminal sliding surface. The resulting second order sliding mode can effectively reduce chattering in the control input. Simulation results confirm the supremacy of the proposed optimal second order sliding mode control over some existing sliding mode controllers in controlling nonlinear systems affected by uncertainty. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

Design and optimization of LCL-VSC grid-tied converter having short circuit fault current limiting ability

NASA Astrophysics Data System (ADS)

Liu, Mengqi; Liu, Haijun; Wang, Zhikai

2017-01-01

Traditional LCL grid-tied converters haven't the ability to limit the short-circuit fault current and only remove grid-connected converter using the breaker. However, the VSC converters become uncontrollable after the short circuit fault cutting off and the power switches may be damaged if the circuit breaker removes slowly. Compared to the filter function of the LCL passive components in traditional VSC converters, the novel LCL-VSC converter has the ability of limiting the short circuit fault current using the reasonable designed LCL parameters. In this paper the mathematical model of the LCL converter is established and the characteristics of the short circuit fault current generated by the ac side and dc side are analyzed. Thus one design and optimization scheme of the reasonable LCL passive parameter is proposed for the LCL-VSC converter having short circuit fault current limiting ability. In addition to ensuring the LCL passive components filtering the high-frequency harmonic, this scheme also considers the impedance characteristics to limit the fault current of AC and DC short circuit fault respectively flowing through the power switch no more than the maximum allowable operating current, in order to make the LCL converter working continuously. Finally, the 200kW simulation system is set up to prove the validity and feasibility of the theoretical analysis using the proposed design and optimization scheme.

Clinical chemistry measurements with commercially available test slides on a smartphone platform: Colorimetric determination of glucose and urea.

PubMed

Wu, Yuanyuan; Boonloed, Anukul; Sleszynski, Neal; Koesdjojo, Myra; Armstrong, Chadd; Bracha, Shay; Remcho, Vincent T

2015-08-25

Rapidly increasing healthcare costs in economically advantaged countries are currently unsustainable, while in many developing nations, even 50-year-old technologies are too expensive to implement. New and unconventional technologies are being explored as solutions to this problem. In this study, we examined the use of a smartphone as the detection platform for 2 well-developed, relatively inexpensive, commercially available clinical chemistry assays as a model for rapid and inexpensive clinical diagnostic testing. An Apple iPhone 4 camera phone equipped with a color analysis application (ColorAssist) was combined with Vitros® glucose and urea colorimetric assays. Color images of assay slides at various concentrations of glucose or urea were collected with the iPhone 4 and quantitated in three different spectral ranges (red/green/blue or RGB) using the ColorAssist app. When the diffuse reflectance data was converted into absorbance, it was possible to quantitate glucose or blood urea nitrogen (BUN) over their clinically important concentration ranges (30-515mg/dl for glucose or 2-190mg/dl for BUN), with good linearity (R(2)=0.9994 or 0.9996, respectively [n=5]). Data collected using the iPhone 4 and canine serum samples were in agreement with results from the instrumental "gold standard" (Beckman Coulter AU480 Chemistry System) (R(2)=0.9966 and slope=1.0001 for glucose; R(2)=0.9958 and slope=0.9454 for BUN). Glucose determinations of serum samples made using this smartphone method were as accurate as or more accurate than a commercial colorimetric dry slide analyzer (Heska® Element DC Chemistry Analyzer, Loveland, CO) and 2 glucometers: ReliOn® Ultima (Abbott Diabetes Care Inc) and Presto® (AgaMatrix Inc.H). BUN determinations made using the smartphone approach were comparable in accuracy to the Heska instrument. This demonstration shows that smartphones have the potential to be used as simple, effective colorimetric detectors for quantitative diagnostic tests, and may be applicable for both point-of-care applications in the developed world and field deployment in developing nations. Copyright © 2015 Elsevier B.V. All rights reserved.

Catalytic analysis of APOBEC3G involving real-time NMR spectroscopy reveals nucleic acid determinants for deamination.

PubMed

Kamba, Keisuke; Nagata, Takashi; Katahira, Masato

2015-01-01

APOBEC3G (A3G) is a single-stranded DNA-specific cytidine deaminase that preferentially converts cytidine to uridine at the third position of triplet cytosine (CCC) hotspots. A3G restricts the infectivity of viruses, such as HIV-1, by targeting CCC hotspots scattered through minus DNA strands, reverse-transcribed from genomic RNA. Previously, we developed a real-time NMR method and elucidated the origin of the 3'→5' polarity of deamination of DNA by the C-terminal domain of A3G (CD2), which is a phenomenon by which a hotspot located closer to the 5'-end is deaminated more effectively than one less close to the 5'-end, through quantitative analysis involving nonspecific binding to and sliding along DNA. In the present study we applied the real-time NMR method to analyze the catalytic activity of CD2 toward DNA oligonucleotides containing a nucleotide analog at a single or multiple positions. Analyses revealed the importance of the sugar and base moieties throughout the consecutive 5 nucleotides, the CCC hotspot being positioned at the center. It was also shown that the sugar or base moieties of the nucleotides outside this 5 nucleotide recognition sequence are also relevant as to CD2's activity. Analyses involving DNA oligonucleotides having two CCC hotspots linked by a long sequence of either deoxyribonucleotides, ribonucleotides or abasic deoxyribonucleotides suggested that the phosphate backbone is required for CD2 to slide along the DNA strand and to exert the 3'→5' polarity. Examination of the effects of different salt concentrations on the 3'→5' polarity indicated that the higher the salt concentration, the less prominent the 3'→5' polarity. This is most likely the result of alleviation of sliding due to a decrease in the affinity of CD2 with the phosphate backbone at high salt concentrations. We also investigated the reactivity of substrates containing 5-methylcytidine (5mC) or 5-hydroxymethylcytidine, and found that A3G exhibited low activity toward 5mC.

An Adaptive Supervisory Sliding Fuzzy Cerebellar Model Articulation Controller for Sensorless Vector-Controlled Induction Motor Drive Systems

PubMed Central

Wang, Shun-Yuan; Tseng, Chwan-Lu; Lin, Shou-Chuang; Chiu, Chun-Jung; Chou, Jen-Hsiang

2015-01-01

This paper presents the implementation of an adaptive supervisory sliding fuzzy cerebellar model articulation controller (FCMAC) in the speed sensorless vector control of an induction motor (IM) drive system. The proposed adaptive supervisory sliding FCMAC comprised a supervisory controller, integral sliding surface, and an adaptive FCMAC. The integral sliding surface was employed to eliminate steady-state errors and enhance the responsiveness of the system. The adaptive FCMAC incorporated an FCMAC with a compensating controller to perform a desired control action. The proposed controller was derived using the Lyapunov approach, which guarantees learning-error convergence. The implementation of three intelligent control schemes—the adaptive supervisory sliding FCMAC, adaptive sliding FCMAC, and adaptive sliding CMAC—were experimentally investigated under various conditions in a realistic sensorless vector-controlled IM drive system. The root mean square error (RMSE) was used as a performance index to evaluate the experimental results of each control scheme. The analysis results indicated that the proposed adaptive supervisory sliding FCMAC substantially improved the system performance compared with the other control schemes. PMID:25815450

An adaptive supervisory sliding fuzzy cerebellar model articulation controller for sensorless vector-controlled induction motor drive systems.

PubMed

Wang, Shun-Yuan; Tseng, Chwan-Lu; Lin, Shou-Chuang; Chiu, Chun-Jung; Chou, Jen-Hsiang

2015-03-25

This paper presents the implementation of an adaptive supervisory sliding fuzzy cerebellar model articulation controller (FCMAC) in the speed sensorless vector control of an induction motor (IM) drive system. The proposed adaptive supervisory sliding FCMAC comprised a supervisory controller, integral sliding surface, and an adaptive FCMAC. The integral sliding surface was employed to eliminate steady-state errors and enhance the responsiveness of the system. The adaptive FCMAC incorporated an FCMAC with a compensating controller to perform a desired control action. The proposed controller was derived using the Lyapunov approach, which guarantees learning-error convergence. The implementation of three intelligent control schemes--the adaptive supervisory sliding FCMAC, adaptive sliding FCMAC, and adaptive sliding CMAC--were experimentally investigated under various conditions in a realistic sensorless vector-controlled IM drive system. The root mean square error (RMSE) was used as a performance index to evaluate the experimental results of each control scheme. The analysis results indicated that the proposed adaptive supervisory sliding FCMAC substantially improved the system performance compared with the other control schemes.

Parametric pendulum based wave energy converter

NASA Astrophysics Data System (ADS)

Yurchenko, Daniil; Alevras, Panagiotis

2018-01-01

The paper investigates the dynamics of a novel wave energy converter based on the parametrically excited pendulum. The herein developed concept of the parametric pendulum allows reducing the influence of the gravity force thereby significantly improving the device performance at a regular sea state, which could not be achieved in the earlier proposed original point-absorber design. The suggested design of a wave energy converter achieves a dominant rotational motion without any additional mechanisms, like a gearbox, or any active control involvement. Presented numerical results of deterministic and stochastic modeling clearly reflect the advantage of the proposed design. A set of experimental results confirms the numerical findings and validates the new design of a parametric pendulum based wave energy converter. Power harvesting potential of the novel device is also presented.

Three-dimensional models of conventional and vertical junction laser-photovoltaic energy converters

NASA Technical Reports Server (NTRS)

Heinbockel, John H.; Walker, Gilbert H.

1988-01-01

Three-dimensional models of both conventional planar junction and vertical junction photovoltaic energy converters have been constructed. The models are a set of linear partial differential equations and take into account many photoconverter design parameters. The model is applied to Si photoconverters; however, the model may be used with other semiconductors. When used with a Nd laser, the conversion efficiency of the Si vertical junction photoconverter is 47 percent, whereas the efficiency for the conventional planar Si photoconverter is only 17 percent. A parametric study of the Si vertical junction photoconverter is then done in order to describe the optimum converter for use with the 1.06-micron Nd laser. The efficiency of this optimized vertical junction converter is 44 percent at 1 kW/sq cm.

Digital control of diode laser for atmospheric spectroscopy

NASA Technical Reports Server (NTRS)

Menzies, R. T.; Rutledge, C. W. (Inventor)

1985-01-01

A system is described for remote absorption spectroscopy of trace species using a diode laser tunable over a useful spectral region of 50 to 200 cm(-1) by control of diode laser temperature over range from 15 K to 100 K, and tunable over a smaller region of typically 0.1 to 10 cm(-1) by control of the diode laser current over a range from 0 to 2 amps. Diode laser temperature and current set points are transmitted to the instrument in digital form and stored in memory for retrieval under control of a microprocessor during measurements. The laser diode current is determined by a digital to analog converter through a field effect transistor for a high degree of ambient temperature stability, while the laser diode temperature is determined by set points entered into a digital to analog converter under control of the microprocessor. Temperature of the laser diode is sensed by a sensor diode to provide negative feedback to the temperature control circuit that responds to the temperature control digital to analog converter.

Slide system for machine tools

DOEpatents

Douglass, S.S.; Green, W.L.

1980-06-12

The present invention relates to a machine tool which permits the machining of nonaxisymmetric surfaces on a workpiece while rotating the workpiece about a central axis of rotation. The machine tool comprises a conventional two-slide system (X-Y) with one of these slides being provided with a relatively short travel high-speed auxiliary slide which carries the material-removing tool. The auxiliary slide is synchronized with the spindle speed and the position of the other two slides and provides a high-speed reciprocating motion required for the displacement of the cutting tool for generating a nonaxisymmetric surface at a selected location on the workpiece.

Slide system for machine tools

DOEpatents

Douglass, Spivey S.; Green, Walter L.

1982-01-01

The present invention relates to a machine tool which permits the machining of nonaxisymmetric surfaces on a workpiece while rotating the workpiece about a central axis of rotation. The machine tool comprises a conventional two-slide system (X-Y) with one of these slides being provided with a relatively short travel high-speed auxiliary slide which carries the material-removing tool. The auxiliary slide is synchronized with the spindle speed and the position of the other two slides and provides a high-speed reciprocating motion required for the displacement of the cutting tool for generating a nonaxisymmetric surface at a selected location on the workpiece.

Factors to keep in mind when introducing virtual microscopy.

PubMed

Glatz-Krieger, Katharina; Spornitz, Udo; Spatz, Alain; Mihatsch, Michael J; Glatz, Dieter

2006-03-01

Digitization of glass slides and delivery of so-called virtual slides (VS) emulating a real microscope over the Internet have become reality due to recent improvements in technology. We have implemented a virtual microscope for instruction of medical students and for continuing medical education. Up to 30,000 images per slide are captured using a microscope with an automated stage. The images are post-processed and then served by a plain hypertext transfer protocol (http)-server. A virtual slide client (vMic) based on Macromedia's Flash MX, a highly accepted technology available on every modern Web browser, has been developed. All necessary virtual slide parameters are stored in an XML file together with the image. Evaluation of the courses by questionnaire indicated that most students and many but not all pathologists regard virtual slides as an adequate replacement for traditional slides. All our virtual slides are publicly accessible over the World Wide Web (WWW) at http://vmic.unibas.ch . Recently, several commercially available virtual slide acquisition systems (VSAS) have been developed that use various technologies to acquire and distribute virtual slides. These systems differ in speed, image quality, compatibility, viewer functionalities and price. This paper gives an overview of the factors to keep in mind when introducing virtual microscopy.

Second order sliding mode control for a quadrotor UAV.

PubMed

Zheng, En-Hui; Xiong, Jing-Jing; Luo, Ji-Liang

2014-07-01

A method based on second order sliding mode control (2-SMC) is proposed to design controllers for a small quadrotor UAV. For the switching sliding manifold design, the selection of the coefficients of the switching sliding manifold is in general a sophisticated issue because the coefficients are nonlinear. In this work, in order to perform the position and attitude tracking control of the quadrotor perfectly, the dynamical model of the quadrotor is divided into two subsystems, i.e., a fully actuated subsystem and an underactuated subsystem. For the former, a sliding manifold is defined by combining the position and velocity tracking errors of one state variable, i.e., the sliding manifold has two coefficients. For the latter, a sliding manifold is constructed via a linear combination of position and velocity tracking errors of two state variables, i.e., the sliding manifold has four coefficients. In order to further obtain the nonlinear coefficients of the sliding manifold, Hurwitz stability analysis is used to the solving process. In addition, the flight controllers are derived by using Lyapunov theory, which guarantees that all system state trajectories reach and stay on the sliding surfaces. Extensive simulation results are given to illustrate the effectiveness of the proposed control method. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

Parametric and non-parametric masking of randomness in sequence alignments can be improved and leads to better resolved trees.

PubMed

Kück, Patrick; Meusemann, Karen; Dambach, Johannes; Thormann, Birthe; von Reumont, Björn M; Wägele, Johann W; Misof, Bernhard

2010-03-31

Methods of alignment masking, which refers to the technique of excluding alignment blocks prior to tree reconstructions, have been successful in improving the signal-to-noise ratio in sequence alignments. However, the lack of formally well defined methods to identify randomness in sequence alignments has prevented a routine application of alignment masking. In this study, we compared the effects on tree reconstructions of the most commonly used profiling method (GBLOCKS) which uses a predefined set of rules in combination with alignment masking, with a new profiling approach (ALISCORE) based on Monte Carlo resampling within a sliding window, using different data sets and alignment methods. While the GBLOCKS approach excludes variable sections above a certain threshold which choice is left arbitrary, the ALISCORE algorithm is free of a priori rating of parameter space and therefore more objective. ALISCORE was successfully extended to amino acids using a proportional model and empirical substitution matrices to score randomness in multiple sequence alignments. A complex bootstrap resampling leads to an even distribution of scores of randomly similar sequences to assess randomness of the observed sequence similarity. Testing performance on real data, both masking methods, GBLOCKS and ALISCORE, helped to improve tree resolution. The sliding window approach was less sensitive to different alignments of identical data sets and performed equally well on all data sets. Concurrently, ALISCORE is capable of dealing with different substitution patterns and heterogeneous base composition. ALISCORE and the most relaxed GBLOCKS gap parameter setting performed best on all data sets. Correspondingly, Neighbor-Net analyses showed the most decrease in conflict. Alignment masking improves signal-to-noise ratio in multiple sequence alignments prior to phylogenetic reconstruction. Given the robust performance of alignment profiling, alignment masking should routinely be used to improve tree reconstructions. Parametric methods of alignment profiling can be easily extended to more complex likelihood based models of sequence evolution which opens the possibility of further improvements.

Deformation and stabilisation mechanisms of slow rock slides in crystalline bedrock

NASA Astrophysics Data System (ADS)

Zangerl, C.; Prager, C.

2009-04-01

Deep-seated rock slides are slope instabilities which are characterised by deformation along one or several shear zones where most of the measured total slope displacement localizes. Generally, a high danger potential is given when rock slides fail in a rapid manner characterised by very high sliding velocities and/or when they develop into long run-out rock avalanches. However several field surveys and deformation monitoring data show that numerous deep-seated rock slides do not fail in a high velocity regime. In fact, many slides creep downwards at rates of some centimetres per year or even less and do not show any evidence for non-reversible acceleration in the past or in the future. Furthermore some of these slope instabilities are actually inactive (dormant) or have even reached a stabilised final state. Deformation monitoring on active rock slides show that acceleration phases characterised by velocities up to meters per day can occur. The trigger for these phases can be manifold and include heavy rainfall, snow melt, water level fluctuations of reservoirs at the slope foot, changes in the slope's equilibrium state due to antecedent slow creeping processes, changes in the material behaviour within the sliding zone, erosion along the foot of the slope, etc. Whereas the role of these triggers in promoting phases of acceleration are generally understood, the same can not be said regarding the kinematics and dynamic processes/mechanisms by which rock slide masses re-stabilise once the trigger impetus has been removed. In the context of this study the term "stabilisation" is used for rock slides which decelerate from high velocities to slow base activities or even stop moving after a certain amount of displacement. Given that reliable rock slide forecasts require the fundamental understanding of possible slope stabilisation mechanisms this study focuses on field-based and numerically obtained key-properties which influence the long-term slope deformation behaviour. On a regional scale several valleys located in amphibolites, ortho- and paragneisses of the Ötztal-Stubai crystalline basement (i.e. Kaunertal, Pitztal, Ötztal, Lüsenstal, all located in North Tyrol, Austria) were investigated. Therefore geological and morphological basis data were compiled and re-evaluated, remote sensing methods (i.e. airborne laser scanning terrain models and orthofotos) applied and field mapping campaigns performed. On a local scale several rock slides were investigated and analysed in high detail with regard to their lithological and structural inventory, geometry of sliding masses and -zones, failure mechanisms, kinematics and temporal deformation characteristics. Field data clearly show that competent rock masses, e.g. orthogneisses and amphibolites, are affected by rapid failure events and therefore are characterised by "brittle" rock mass behaviour. In contrast, the majority of the slowly moving and "self-stabilising" rock slides are located totally or partly in mica-rich incompetent crystalline rock masses, e.g. paragneisses and micaschists, and are characterised by moderately dipping sliding zones. Apart from a causal lithological influence, numerous field observations demonstrate a major influence of pre-existing geological structures on the formation and deformation behaviour of these rock slides. The nature of rock slides implies that the temporal deformation behaviour is primarily dominated by two key-features of the sliding zone i.e. the mechanical properties (shear strain strengthening or weakening) and the effective in-situ stresses. The in-situ stresses along a sliding zone are influenced by the geometry of both the sliding mass and sliding zone, the internal deformation of the sliding mass and the pore pressures. All these properties can vary during progressive shear displacements. Especially large shear displacements in the range of tens to hundreds of metres along a distinct sliding zone can cause significant in-situ stress changes which in turn may influence the slope deformation behaviour and stabilisation mechanisms. In order to study these processes for selected case studies in paragneissic rock masses the impact of the sliding mass geometry and sliding zone shape on the in-situ stresses has been investigated by applying the discrete element method. This numerical approach enables the simulation of large shear displacements and complex block assembly interactions. Results show that slope stabilisation can be achieved when the dip angle of the sliding zone flattens downslope. In this case and after a certain amount of displacement the lower part of the rock slide mass reaches stable slope conditions (shear strength of the sliding zone material exceeds the shear stress acting on the sliding zone) and acts as a resisting mass for the still unstable upper part of the slope. Furthermore numerical models show that secondary slides at the lower part of the slope have a similar effect. In both case cases the observed slope stabilisation can be clearly attributed to the formation of natural buttressing masses at the toe.

Whole slide images and digital media in pathology education, testing, and practice: the Oklahoma experience.

PubMed

Fung, Kar-Ming; Hassell, Lewis A; Talbert, Michael L; Wiechmann, Allan F; Chaser, Brad E; Ramey, Joel

2012-01-01

Examination of glass slides is of paramount importance in pathology training. Until the introduction of digitized whole slide images that could be accessed through computer networks, the sharing of pathology slides was a major logistic issue in pathology education and practice. With the help of whole slide images, our department has developed several online pathology education websites. Based on a modular architecture, this program provides online access to whole slide images, still images, case studies, quizzes and didactic text at different levels. Together with traditional lectures and hands-on experiences, it forms the back bone of our histology and pathology education system for residents and medical students. The use of digitized whole slide images has a.lso greatly improved the communication between clinicians and pathologist in our institute.

Sliding wear and friction behaviour of zircaloy-4 in water

NASA Astrophysics Data System (ADS)

Sharma, Garima; Limaye, P. K.; Jadhav, D. T.

2009-11-01

In water cooled nuclear reactors, the sliding of fuel bundles in fuel channel handling system can lead to severe wear and it is an important topic to study. In the present study, sliding wear behaviour of zircaloy-4 was investigated in water (pH ˜ 10.5) using ball-on-plate sliding wear tester. Sliding wear resistance zircaloy-4 against SS 316 was examined at room temperature. Sliding wear tests were carried out at different load and sliding frequencies. The coefficient of friction of zircaloy-4 was also measured during each tests and it was found to decrease slightly with the increase in applied load. The micro-mechanisms responsible for wear in zircaloy-4 were identified to be microcutting, micropitting and microcracking of deformed subsurface zones in water.

Diagnostic digital cytopathology: Are we ready yet?

PubMed Central

House, Jarret C.; Henderson-Jackson, Evita B.; Johnson, Joseph O.; Lloyd, Mark C.; Dhillon, Jasreman; Ahmad, Nazeel; Hakam, Ardeshir; Khalbuss, Walid E.; Leon, Marino E.; Chhieng, David; Zhang, Xiaohui; Centeno, Barbara A.; Bui, Marilyn M.

2013-01-01

Background: The cytology literature relating to diagnostic accuracy using whole slide imaging is scarce. We studied the diagnostic concordance between glass and digital slides among diagnosticians with different profiles to assess the readiness of adopting digital cytology in routine practice. Materials and Methods: This cohort consisted of 22 de-identified previously screened and diagnosed cases, including non-gynecological and gynecological slides using standard preparations. Glass slides were digitalized using Aperio ScanScope XT (×20 and ×40). Cytopathologists with (3) and without (3) digital experience, cytotechnologists (4) and senior pathology residents (2) diagnosed the digital slides independently first and recorded the results. Glass slides were read and recorded separately 1-3 days later. Accuracy of diagnosis, time to diagnosis and diagnostician's profile were analyzed. Results: Among 22 case pairs and four study groups, correct diagnosis (93% vs. 86%) was established using glass versus digital slides. Both methods more (>95%) accurately diagnosed positive cases than negatives. Cytopathologists with no digital experience were the most accurate in digital diagnosis, even the senior members. Cytotechnologists had the fastest diagnosis time (3 min/digital vs. 1.7 min/glass), but not the best accuracy. Digital time was 1.5 min longer than glass-slide time/per case for cytopathologists and cytotechnologists. Senior pathology residents were slower and less accurate with both methods. Cytopathologists with digital experience ranked 2nd fastest in time, yet last in accuracy for digital slides. Conclusions: There was good overall diagnostic agreement between the digital whole-slide images and glass slides. Although glass slide diagnosis was more accurate and faster, the results of technologists and pathologists with no digital cytology experience suggest that solid diagnostic ability is a strong indicator for readiness of digital adoption. PMID:24392242

Issues for application of virtual microscopy to cytoscreening, perspectives based on questionnaire to Japanese cytotechnologists

PubMed Central

Mori, Ichiro; Nunobiki, Osamu; Ozaki, Takashi; Taniguchi, Emiko; Kakudo, Kennichi

2008-01-01

To clarify the issues associated with the applications of virtual microscopy to the daily cytology slide screening, we conducted a survey at a slide conference of cytology. The survey was conducted specifically to the Japanese cytology technologists who use microscopes on a routine basis. Virtual slides (VS) were prepared from cytology slides using NanoZoomer (Hamamatsu Photonics, Japan), which is capable of adjusting focus on any part of the slide. A total of ten layers were scanned from the same slides, with 2 micrometer intervals. To simulate the cytology slide screening, no marker points were created. The total data volume of six slides was approximately 25 Giga Bytes. The slides were stored on the Windows 2003 Server, and were made accessible on the web to the cytology technologists. Most cytotechnologists answered "Satisfied" or "Acceptable" to the VS resolution and drawing speed, and "Dissatisfied" to the operation speed. To the ten layered focus, an answer "insufficient" was slightly more frequent than the answer "sufficient", while no one answered "fewer is acceptable" or "no need for depth". As for the use of cytology slide screening, answers "usable, but requires effort" and "not usable" were about equal in number. In a Japanese cytology meeting, a unique VS system has been used in slide conferences with markings to the discussion point for years. Therefore, Japanese cytotechnologists are relatively well accustomed to the use of VS, and the survey results showed that they regarded VS more positively than we expected. Currently, VS has the acceptable resolution and drawing speed even on the web. Most cytotechnologists regard the focusing capability crucial for cytology slide screening, but the consequential enlargement of data size, longer scanning time, and slower drawing speed are the issues that are yet to be resolved. PMID:18673503

Interaction of the Sliding Clamp β-Subunit and Hda, a DnaA-Related Protein

PubMed Central

Kurz, Mareike; Dalrymple, Brian; Wijffels, Gene; Kongsuwan, Kritaya

2004-01-01

In Escherichia coli, interactions between the replication initiation protein DnaA, the β subunit of DNA polymerase III (the sliding clamp protein), and Hda, the recently identified DnaA-related protein, are required to convert the active ATP-bound form of DnaA to an inactive ADP-bound form through the accelerated hydrolysis of ATP. This rapid hydrolysis of ATP is proposed to be the main mechanism that blocks multiple initiations during cell cycle and acts as a molecular switch from initiation to replication. However, the biochemical mechanism for this crucial step in DNA synthesis has not been resolved. Using purified Hda and β proteins in a plate binding assay and Ni-nitrilotriacetic acid pulldown analysis, we show for the first time that Hda directly interacts with β in vitro. A new β-binding motif, a hexapeptide with the consensus sequence QL[SP]LPL, related to the previously identified β-binding pentapeptide motif (QL[SD]LF) was found in the amino terminus of the Hda protein. Mutants of Hda with amino acid changes in the hexapeptide motif are severely defective in their ability to bind β. A 10-amino-acid peptide containing the E. coli Hda β-binding motif was shown to compete with Hda for binding to β in an Hda-β interaction assay. These results establish that the interaction of Hda with β is mediated through the hexapeptide sequence. We propose that this interaction may be crucial to the events that lead to the inactivation of DnaA and the prevention of excess initiation of rounds of replication. PMID:15150238

Interaction of the sliding clamp beta-subunit and Hda, a DnaA-related protein.

PubMed

Kurz, Mareike; Dalrymple, Brian; Wijffels, Gene; Kongsuwan, Kritaya

2004-06-01

In Escherichia coli, interactions between the replication initiation protein DnaA, the beta subunit of DNA polymerase III (the sliding clamp protein), and Hda, the recently identified DnaA-related protein, are required to convert the active ATP-bound form of DnaA to an inactive ADP-bound form through the accelerated hydrolysis of ATP. This rapid hydrolysis of ATP is proposed to be the main mechanism that blocks multiple initiations during cell cycle and acts as a molecular switch from initiation to replication. However, the biochemical mechanism for this crucial step in DNA synthesis has not been resolved. Using purified Hda and beta proteins in a plate binding assay and Ni-nitrilotriacetic acid pulldown analysis, we show for the first time that Hda directly interacts with beta in vitro. A new beta-binding motif, a hexapeptide with the consensus sequence QL[SP]LPL, related to the previously identified beta-binding pentapeptide motif (QL[SD]LF) was found in the amino terminus of the Hda protein. Mutants of Hda with amino acid changes in the hexapeptide motif are severely defective in their ability to bind beta. A 10-amino-acid peptide containing the E. coli Hda beta-binding motif was shown to compete with Hda for binding to beta in an Hda-beta interaction assay. These results establish that the interaction of Hda with beta is mediated through the hexapeptide sequence. We propose that this interaction may be crucial to the events that lead to the inactivation of DnaA and the prevention of excess initiation of rounds of replication.

Dip-slope and Dip-slope Failures in Taiwan - a Review

NASA Astrophysics Data System (ADS)

Lee, C.

2011-12-01

Taiwan is famous for dip-slope and dip-slope slides. Dip-slopes exist at many places in the fold-and-thrust belt of Taiwan. Under active cutting of stream channels and man-made excavations, a dip-slope may become unstable and susceptible for mass sliding. Daylight of a bedding parallel clay seam is the most dangerous type for dip-slope sliding. Buckling or shear-off features may also happen at toe of a long dip-slope. Besides, a dip-slope is also dangerous for shallow debris slides, if the slope angle is between 25 to 45 degrees and the debris (colluvium or slope wash) is thick (>1m). These unstable slopes may slide during a triggering event, earthquake or typhoon storm; or even slide without a triggering event, like the 2010 Tapu case. Initial buckling feature had been found in the dip-slope of the Feitsui arch dam abutment after detailed explorations. Shear-off feature have also been found in dip-slope located in right bank of the Nahua reservoir after field investigation and drilling. The Chiufengerhshan slide may also be shear-off type. On the other hand, the Tapu, the Tsaoling slides and others are of direct slide type. The Neihoo Bishan slide is a shallow debris slide on dip-slope. All these cases demonstrate the four different types of dip-slope slide. The hazard of a dip-slope should be investigated to cover these possible types of failure. The existence of bedding parallel clay seams is critical for the stability of a dip-slope, either for direct slide or buckling or shear-off type of failure, and is a hot point during investigation. Because, the stability of a dip-slope is changing with time, therefore, detailed explorations to including weathering and erosion rates are also very necessary to ensure the long-term stability of a dip-slope.

Comparative study of tool machinery sliding systems; comparison between plane and cylindrical basic shapes

NASA Astrophysics Data System (ADS)

Glăvan, D. O.; Babanatsas, T.; Babanatis Merce, R. M.; Glăvan, A.

2018-01-01

The paper brings in attention the importance that the sliding system of a tool machinery is having in the final precision of the manufacturing. We are basically comparing two type of slides, one constructed with plane surfaces and the other one with circular cross-sections (as known as cylindrical slides), analysing each solution from the point of view of its technology of manufacturing, of the precision that the particular slides are transferring to the tool machinery, cost of production, etc. Special attention is given to demonstrate theoretical and to confirm by experimental works what is happening with the stress distribution in the case of plane slides and cylindrical slides, both in longitudinal and in cross-over sections. Considering the results obtained for the stress distribution in the transversal and longitudinal cross sections, by composing them, we can obtain the stress distribution on the semicircular slide. Based on the results, special solutions for establishing the stress distribution between two surfaces without interact in the contact zone have been developed.

A Sliding Mode Controller Using Nonlinear Sliding Surface Improved With Fuzzy Logic: Application to the Coupled Tanks System

NASA Astrophysics Data System (ADS)

Boubakir, A.; Boudjema, F.; Boubakir, C.

2008-06-01

This paper proposes an approach of hybrid control that is based on the concept of combining fuzzy logic and the methodology of sliding mode control (SMC). In the present works, a first-order nonlinear sliding surface is presented, on which the developed control law is based. Mathematical proof for the stability and convergence of the system is presented. In order to reduce the chattering in sliding mode control, a fixed boundary layer around the switch surface is used. Within the boundary layer, since the fuzzy logic control is applied, the chattering phenomenon, which is inherent in a sliding mode control, is avoided by smoothing the switch signal. Outside the boundary, the sliding mode control is applied to driving the system states into the boundary layer. Experimental studies carried out on a coupled Tanks system indicate that the proposed fuzzy sliding mode control (FSMC) is a good candidate for control applications.

Fresh and aged human lymphocyte metaphase slides are equally usable for GTG banding.

PubMed

Sajjad, Naheed; Haque, Sayedul; SBurney, Syed Intesar; Shahid, Syed Muhammad; Zehra, Sitwat; Azhar, Abid

2014-09-01

The identification of chromosomes for routine cytogenetic analysis is based on quality of metaphases and good banding pattern. Fresh slides of human lymphocytes have been shown to produce good bands for the identification of chromosomes morphology. G-bands by Trypsin using Giemsa (GTG) banding of aged slides is generally considered hard to get desired band pattern of chromosomes persistently. The current study is focused on GTG banding of aged slides. A total of 340 subjects including 290 primary infertile and 50 fertile were selected. The blood samples were drawn aseptically for cytogenetic analysis. Lymphocytes were cultured and GTG banding was done on 1440 glass slides. Giemsa trypsin banding of aged slides were done by adjusting average trypsin time for each month according to the slide age and metaphase concentration. Correlation analyses showed a significant and positive correlation between slide ageing and trypsin pre-treatment time. The results of this study suggest that, the fresh and aged human lymphocyte metaphases are equally usable for GTG banding.

Modeling the Physics of Sliding Objects on Rotating Space Elevators and Other Non-relativistic Strings

NASA Astrophysics Data System (ADS)

Golubovic, Leonardo; Knudsen, Steven

2017-01-01

We consider general problem of modeling the dynamics of objects sliding on moving strings. We introduce a powerful computational algorithm that can be used to investigate the dynamics of objects sliding along non-relativistic strings. We use the algorithm to numerically explore fundamental physics of sliding climbers on a unique class of dynamical systems, Rotating Space Elevators (RSE). Objects sliding along RSE strings do not require internal engines or propulsion to be transported from the Earth's surface into outer space. By extensive numerical simulations, we find that sliding climbers may display interesting non-linear dynamics exhibiting both quasi-periodic and chaotic states of motion. While our main interest in this study is in the climber dynamics on RSEs, our results for the dynamics of sliding object are of more general interest. In particular, we designed tools capable of dealing with strongly nonlinear phenomena involving moving strings of any kind, such as the chaotic dynamics of sliding climbers observed in our simulations.

Reaction of perfluoroalkylpolyethers (PFPE) with 440C steel in vacuum under sliding conditions at room temperature

NASA Technical Reports Server (NTRS)

Mori, Shigeyuki; Morales, Wilfredo

1989-01-01

Reactions of perfluoroalkylpolyethers (PFPE: Fomblin, Demnum and Krytox) were studied during the sliding contact of stainless steel specimens under ultrahigh vacuum conditions. All three fluids reacted with the steel specimens during sliding. Fomblin, which has acetal linkages, decomposed under the sliding conditions generating gaseous products, (COF2 and fluorinated carbons) which were detected by a quadrupole mass spectrometer. Gaseous products were not detected for the Demnum and Krytox fluids. The amount of gaseous products from Fomblin increased with increasing sliding speed. At the end of the sliding experiments, the wear scar and deposits on the specimens were examined by small spot size XPS. The oxide layer on the specimen surface was removed during sliding, and metal fluorides were formed on the worn surface. The surface of the wear scar and deposits were covered with adsorbed PFPE. Based on these results, it was concluded that the decomposition reaction on Fomblin was initiated by contacting the fluid with a fresh metal surface which was formed during sliding.

Comparison of glass slides and various digital-slide modalities for cytopathology screening and interpretation.

PubMed

Hanna, Matthew G; Monaco, Sara E; Cuda, Jacqueline; Xing, Juan; Ahmed, Ishtiaque; Pantanowitz, Liron

2017-09-01

Whole-slide imaging in cytology is limited when glass slides are digitized without z-stacks for focusing. Different vendors have started to provide z-stacking solutions to overcome this limitation. The Panoptiq imaging system allows users to create digital files combining low-magnification panoramic images with regions of interest (ROIs) that are imaged with high-magnification z-stacks. The aim of this study was to compare such panoramic images with conventional whole-slide images and glass slides for the tasks of screening and interpretation in cytopathology. Thirty glass slides, including 10 ThinPrep Papanicolaou tests and 20 nongynecologic cytology cases, were digitized with an Olympus BX45 integrated microscope with an attached Prosilica GT camera. ViewsIQ software was used for image acquisition and viewing. These glass slides were also scanned on an Aperio ScanScope XT at ×40 (0.25 μm/pixel) with 1 z-plane and were viewed with ImageScope software. Digital and glass sides were screened and dotted/annotated by a cytotechnologist and were subsequently reviewed by 3 cytopathologists. For panoramic images, the cytotechnologist manually created digital maps and selected representative ROIs to generate z-stacks at a higher magnification. After 3-week washout periods, panoramic images were compared with Aperio digital slides and glass slides. The Panoptiq system permitted fine focusing of thick smears and cell clusters. In comparison with glass slides, the average screening times were 5.5 and 1.8 times longer with Panoptiq and Aperio images, respectively, but this improved with user experience. There was no statistical difference in diagnostic concordance between all 3 modalities. Users' diagnostic confidence was also similar for all modalities. The Aperio whole-slide scanner with 1 z-plane scanning and the Panoptiq imaging system with z-stacking are both suitable for cytopathology screening and interpretation. However, ROI z-stacks do offer a superior mechanism for overcoming focusing problems commonly encountered with digital cytology slides. Unlike whole-slide imaging, the acquisition of representative z-stack images with the Panoptiq system requires a trained cytologist to create digital files. Cancer Cytopathol 2017;125:701-9. © 2017 American Cancer Society. © 2017 American Cancer Society.

The complex emplacement dynamics and tsunami genesis of the 1888 Ritter Island sector collapse from 3D seismic data

NASA Astrophysics Data System (ADS)

Urlaub, M.; Karstens, J.; Berndt, C.; Watt, S. F.; Micallef, A.; Klaucke, I.; Klaeschen, D.; Brune, S.; Kühn, M.

2017-12-01

On March 13 1888, a large sector of the subaerial and submarine edifice of Ritter Island (Papua New Guinea) collapsed and slid into the Bismarck Sea, triggering a tsunami with run-up heights of more than 25 m on the neighboring islands. The tsunami traveled for more than 600 km and caused destruction in several settlements. German colonists described in detail the timing of the arriving waves. During research cruise SO252 onboard RV Sonne, we collected a comprehensive set of multibeam and sediment echosounder data, seafloor video footage, rock samples, 2D seismic profiles, and a 60 km2 high-resolution Pcable 3D seismic cube. This dataset, combined with the historic eyewitness accounts, allows detailed reconstruction of the large-scale volcanic sector collapse and the associated tsunami genesis. The 3D seismic cube reveals a change of emplacement dynamics during the collapse of the volcanic edifice. The initial failure occurred along a deep slide plane extending from the volcanic cone up to 300 m deep into the seafloor sediments adjacent to the volcanic edifice. Movement of large, intact sediment blocks and shortening characterize this deep-rooted mass-movement. In contrast to the well-preserved mobilization structures in the deep part of the volcanic edifice related to the initial phase of mass movement, there are hardly any deposits of the upper part of the volcanic cone comprising of well-stratified volcaniclastic layers. The 2 km3 cone was mobilized in the final stage of the sector collapse and its highly energetic slide mass eroded deeply into the previously emplaced slide deposits. The fast moving mass was channelized between two volcanic ridges, transported into the basin west of Sakar Island, and then deposited more than 30 km away from its source. We interpret the separation into two phases as the result of decoupling of the sliding mass of the cone from the deeper volcanic edifice. This process may be explained by gravitational acceleration of the sliding mass or a phreatomagmatic explosion due to the contact of the magmatic conduit with seawater.