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Sample records for five-axis cnc flank

  1. Flank wears Simulation by using back propagation neural network when cutting hardened H-13 steel in CNC End Milling

    NASA Astrophysics Data System (ADS)

    Hazza, Muataz Hazza F. Al; Adesta, Erry Y. T.; Riza, Muhammad

    2013-12-01

    High speed milling has many advantages such as higher removal rate and high productivity. However, higher cutting speed increase the flank wear rate and thus reducing the cutting tool life. Therefore estimating and predicting the flank wear length in early stages reduces the risk of unaccepted tooling cost. This research presents a neural network model for predicting and simulating the flank wear in the CNC end milling process. A set of sparse experimental data for finish end milling on AISI H13 at hardness of 48 HRC have been conducted to measure the flank wear length. Then the measured data have been used to train the developed neural network model. Artificial neural network (ANN) was applied to predict the flank wear length. The neural network contains twenty hidden layer with feed forward back propagation hierarchical. The neural network has been designed with MATLAB Neural Network Toolbox. The results show a high correlation between the predicted and the observed flank wear which indicates the validity of the models.

  2. Evaluation of five-axis lathe for producing squib valve housings. Final report

    SciTech Connect

    McGrath, J T

    1994-03-01

    The process of machining squib valve housings is often a complex process involving many different operations on various machines. This process has a long flowtime, and a considerable number of production hours are invested in the finished product. New technology combining traditional turning centers with driven tools, such as milling cutters, has the potential to reduce machining time as well as flowtime. A five-axis computer numerical controlled (CNC) turning machine, with driven tools, was evaluated and determined to reduce both machining hours and flowtime on suitable valve housings.

  3. Five-Axis, Three-Magnetic-Bearing Dynamic Spin Rig

    NASA Technical Reports Server (NTRS)

    Morrison, Carlos R.; Provenza, Andrew; Kurkov, Anatole; Mehmed, Oral; Johnson, Dexter; Montague, Gerald; Duffy, Kirsten; Jansen, Ralph

    2005-01-01

    The Five-Axis, Three-Magnetic-Bearing Dynamic Spin Rig is an apparatus for vibration testing of turbomachine blades in a vacuum at rotational speeds from 0 to 40,000 rpm. This rig includes (1) a vertically oriented shaft on which is mounted an assembly comprising a rotor holding the blades to be tested, (2) two actively controlled heteropolar radial magnetic bearings at opposite ends of the shaft, and (3) an actively controlled magnetic thrust bearing at the upper end of the shaft. This rig is a more capable successor to a prior apparatus, denoted the Dynamic Spin Rig (DSR), that included a vertically oriented shaft with a mechanical thrust bearing at the upper end and a single actively controlled heteropolar radial magnetic bearing at the lower end.

  4. Flank pain

    MedlinePlus

    Pain - side; Side pain ... Flank pain can be a sign of a kidney problem. But, since many organs are in this area, other causes are possible. If you have flank pain and fever , chills, blood in the urine, or ...

  5. Identification of kinematic errors of five-axis machine tool trunnion axis from finished test piece

    NASA Astrophysics Data System (ADS)

    Zhang, Ya; Fu, Jianzhong; Chen, Zichen

    2014-09-01

    Compared with the traditional non-cutting measurement, machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users. However, measurement and calculation of the machining tests in the literature are quite difficult and time-consuming. A new method of the machining tests for the trunnion axis of five-axis machine tool is proposed. Firstly, a simple mathematical model of the cradle-type five-axis machine tool was established by optimizing the coordinate system settings based on robot kinematics. Then, the machining tests based on error-sensitive directions were proposed to identify the kinematic errors of the trunnion axis of cradle-type five-axis machine tool. By adopting the error-sensitive vectors in the matrix calculation, the functional relationship equations between the machining errors of the test piece in the error-sensitive directions and the kinematic errors of C-axis and A-axis of five-axis machine tool rotary table was established based on the model of the kinematic errors. According to our previous work, the kinematic errors of C-axis can be treated as the known quantities, and the kinematic errors of A-axis can be obtained from the equations. This method was tested in Mikron UCP600 vertical machining center. The machining errors in the error-sensitive directions can be obtained by CMM inspection from the finished test piece to identify the kinematic errors of five-axis machine tool trunnion axis. Experimental results demonstrated that the proposed method can reduce the complexity, cost, and the time consumed substantially, and has a wider applicability. This paper proposes a new method of the machining tests for the trunnion axis of five-axis machine tool.

  6. CNC Programming I.

    ERIC Educational Resources Information Center

    Casey, Joe

    This document contains five units for a course in computer numerical control (CNC) for computer-aided manufacturing. It is intended to familiarize students with the principles and techniques necessary to create proper CNC programs manually. Each unit consists of an introduction, instructional objectives, learning materials, learning activities,…

  7. Open architecture CNC system

    SciTech Connect

    Tal, J.; Lopez, A.; Edwards, J.M.

    1995-04-01

    In this paper, an alternative solution to the traditional CNC machine tool controller has been introduced. Software and hardware modules have been described and their incorporation in a CNC control system has been outlined. This type of CNC machine tool controller demonstrates that technology is accessible and can be readily implemented into an open architecture machine tool controller. Benefit to the user is greater controller flexibility, while being economically achievable. PC based, motion as well as non-motion features will provide flexibility through a Windows environment. Up-grading this type of controller system through software revisions will keep the machine tool in a competitive state with minimal effort. Software and hardware modules are mass produced permitting competitive procurement and incorporation. Open architecture CNC systems provide diagnostics thus enhancing maintainability, and machine tool up-time. A major concern of traditional CNC systems has been operator training time. Training time can be greatly minimized by making use of Windows environment features.

  8. Development of a micro-CMM with five-axis scanning touch probe

    NASA Astrophysics Data System (ADS)

    Chu, Chih-Liang; Chen, Hung-Chi

    2016-01-01

    The purpose of this study is to develop with low cost, high precision, low contact force micro-CMM that has fiveaxis scanning touch probe. In this study, the measurement performance of the proposed system is enhanced through the use of a rigid aluminum double-arch-bridge structure to support the five-axis scanning touch probe. Furthermore, the reliability of the scanning probe mechanism of three degrees of freedom was analyzed and validated. in addition two axis (A-axis and C-axis) was added on the scanning probe. This design can be achieved independent of measurement, and minimize the dynamic error. In terms of software, a PC-Based controller was integrates five-axis motion systems with the measurement system through a five-axis control card and a data acquisition card. It also completed the functional modules of Set, Manual and Measurement. In the measurement system, we used our own developed coordinate measurement software, with the XYZ platforms system, rotating mechanism and scanning probe to achieve complex surface measurements. The micro-CMM has a working volume the micro-CMM has a working volume of 80×80×40 mm3 , and the overall dimensions is 486 × 486 × 448 mm.

  9. CAD/CAM/CNC.

    ERIC Educational Resources Information Center

    Domermuth, Dave; And Others

    1996-01-01

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

  10. Fully Suspended, Five-Axis, Three-Magnetic-Bearing Dynamic Spin Rig With Forced Excitation

    NASA Technical Reports Server (NTRS)

    Morrison, Carlos R.; Provenza, Andrew; Kurkov, Anatole; Montague, Gerald; Duffy, Kirsten; Mehmed, Oral; Johnson, Dexter; Jansen, Ralph

    2004-01-01

    The Five-Axis, Three-Magnetic-Bearing Dynamic Spin Rig, a significant advancement in the Dynamic Spin Rig (DSR), is used to perform vibration tests of turbomachinery blades and components under rotating and nonrotating conditions in a vacuum. The rig has as its critical components three magnetic bearings: two heteropolar radial active magnetic bearings and a magnetic thrust bearing. The bearing configuration allows full vertical rotor magnetic suspension along with a feed-forward control feature, which will enable the excitation of various natural blade modes in bladed disk test articles. The theoretical, mechanical, electrical, and electronic aspects of the rig are discussed. Also presented are the forced-excitation results of a fully levitated, rotating and nonrotating, unbladed rotor and a fully levitated, rotating and nonrotating, bladed rotor in which a pair of blades was arranged 180 degrees apart from each other. These tests include the bounce mode excitation of the rotor in which the rotor was excited at the blade natural frequency of 144 Hz. The rotor natural mode frequency of 355 Hz was discerned from the plot of acceleration versus frequency. For nonrotating blades, a blade-tip excitation amplitude of approximately 100 g/A was achieved at the first-bending critical (approximately 144 Hz) and at the first-torsional and second-bending blade modes. A blade-tip displacement of 70 mils was achieved at the first-bending critical by exciting the blades at a forced-excitation phase angle of 908 relative to the vertical plane containing the blades while simultaneously rotating the shaft at 3000 rpm.

  11. Accurate identification and compensation of geometric errors of 5-axis CNC machine tools using double ball bar

    NASA Astrophysics Data System (ADS)

    Lasemi, Ali; Xue, Deyi; Gu, Peihua

    2016-05-01

    Five-axis CNC machine tools are widely used in manufacturing of parts with free-form surfaces. Geometric errors of machine tools have significant effects on the quality of manufactured parts. This research focuses on development of a new method to accurately identify geometric errors of 5-axis CNC machines, especially the errors due to rotary axes, using the magnetic double ball bar. A theoretical model for identification of geometric errors is provided. In this model, both position-independent errors and position-dependent errors are considered as the error sources. This model is simplified by identification and removal of the correlated and insignificant error sources of the machine. Insignificant error sources are identified using the sensitivity analysis technique. Simulation results reveal that the simplified error identification model can result in more accurate estimations of the error parameters. Experiments on a 5-axis CNC machine tool also demonstrate significant reduction in the volumetric error after error compensation.

  12. Analysis, measurement, and compensation of mechanical errors of IR-systems mounted on a five-axis motion table

    NASA Astrophysics Data System (ADS)

    Tomaszunas, Jerzy J.; Plorin, Jürgen; Kipfelsberger, Bernhard; Sonner, Christian; Engelhardt, Wolfgang

    2003-09-01

    LFK-Lenkflugkörpersysteme GmbH develops missile systems for a wide field of military purposes. The Hardware-in-the-Loop (HWIL) facility of LFK in Unterschleissheim uses a five axis motion simulation table and an IR scene projection system. The system is designed for test and evaluation of several missile programs due to the dimensions of the five axis table and it's dynamic performance /1/. In a certain cruise missile program there was the need for system tests with nearly all components of the missile as well as special investigations and validation trials for the subsystem consisting of the IR-seeker and the image processing computer. The components had also to pass their qualification tests with the assistance of the HWIL team. These tests and their analysis are focussed to the mechanical accuracy of the gimbals and resolvers of the IR seeker and the tracking accuracy of the image processing computer. Before starting tests in the HWIL it is absolutely necessary to identify errors caused by mechanical tolerances of the test equipment (e.g. mounting of the seeker and the IR projection system) on the five axis motion simulator. Otherwise the obtained test results includes these errors and lead to incorrect system performance evaluation. There are different mechanical errors in mounting which can occur are analysed below. The main problem is caused by possible shifts of the IR-seeker in a plane perpendicular to the optical axis (with gimbals in zero position). Therefore a procedure has been developed using IR test images, a frame grabber and image processing routines to determine the mounting failures. These can be corrected by using mechanical adjustment tools designed and realised for this purpose.

  13. CNC Preparation Meets Manufacturing Opportunity

    ERIC Educational Resources Information Center

    Cassola, Joel

    2006-01-01

    This article features the machining technology program at Cape Fear Community College (CFCC) of Wilmington, North Carolina. North Carolina's Cape Fear Community College is working to meet diverse industry needs through its CNC training. The school's program has gained the attention of the local manufacturing community and students when it shifted…

  14. CNC electrical discharge machining centers

    SciTech Connect

    Jaggars, S.R.

    1991-10-01

    Computer numerical control (CNC) electrical discharge machining (EDM) centers were investigated to evaluate the application and cost effectiveness of establishing this capability at Allied-Signal Inc., Kansas City Division (KCD). In line with this investigation, metal samples were designed, prepared, and machined on an existing 15-year-old EDM machine and on two current technology CNC EDM machining centers at outside vendors. The results were recorded and evaluated. The study revealed that CNC EDM centers are a capability that should be established at KCD. From the information gained, a machine specification was written and a shop was purchased and installed in the Engineering Shop. The older machine was exchanged for a new model. Additional machines were installed in the Tool Design and Fabrication and Precision Microfinishing departments. The Engineering Shop machine will be principally used for the following purposes: producing deep cavities in small corner radii, machining simulated casting models, machining difficult-to-machine materials, and polishing difficult-to-hand polish mold cavities. 2 refs., 18 figs., 3 tabs.

  15. Kinematic self-calibration of non-contact five-axis measuring machine using improved genetic algorithm

    NASA Astrophysics Data System (ADS)

    Fei, Zhigen; Xu, Xiaojie; Xiao, Yanqiu; Meier, Nicolas; Georgiadis, Anthimos

    2016-02-01

    A novel non-contact, five-axis measuring machine with high measurement accuracy of workpiece dimensions is introduced in this paper. The kinematic model, as well as the kinematic error model, is developed. A self-calibration method using a steel ball is proposed to improve the measurement accuracy in the workspace. The calibration process is low-budget and easy-to-operate due to the fact there is no need to rely on other instruments or devices except for the laser probe carried by the measuring machine itself. The objective function is defined in terms of center-to-center distance deviation, namely the theoretical ball center and tested ball center, and to improve the speed of the convergence rate and to increase the optimization accuracy of the genetic algorithm. The simulation and practical experiments both illustrate the feasibility and validity of the proposed kinematic model and self-calibration method. Finally, the actual measurement results of a Φ12 sphere illustrate that the measurement accuracy of this machine has improved greatly by using calibrated parameters against nominal parameters.

  16. Synthetical Reliability Analysis Model of CNC Software System

    NASA Astrophysics Data System (ADS)

    Xu, Yue; Xia, Yinjie; Wan, Yi

    CNC technology is the core of advanced manufacturing technology, and CNC software system is the very important part of numerical control system. The entire CNC system will not work normally, once the potential failure makes the software invalid. As to the current study of CNC sysytem, in use of the FAULT glitch tree, established a glitch tree for the CNC system; find the minimum cut sets with Fussed method and then according to the probability of several common glitches, make quantitative analysis in the reliability of the CNC system so that scientific ways can be provided for the reliability design, maintenance and management of the CNC system.

  17. Flank solar wind interaction

    NASA Technical Reports Server (NTRS)

    Moses, Stewart L.; Greenstadt, Eugene W.; Coroniti, Ferdinand V.

    1994-01-01

    In this report we will summarize the results of the work performed under the 'Flank Solar Wind Interaction' investigation in support of NASA's Space Physics Guest Investigator Program. While this investigation was focused on the interaction of the Earth's magnetosphere with the solar wind as observed by instruments on the International Sun-Earth Explorer (ISEE) 3 spacecraft, it also represents the culmination of decades of research performed by scientists at TRW on the rich phenomenology of collisionless shocks in space.

  18. Arsia Mons Flank

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This VIS image shows the part of the NE flank of Arsia Mons where it meets the plains. The flank of the volcano is comprised of long flows. Collapse features are present at the flank margin.

    Image information: VIS instrument. Latitude -7.9, Longitude 241.9 East (118.1 West). 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  19. Improving Energy Efficiency in CNC Machining

    NASA Astrophysics Data System (ADS)

    Pavanaskar, Sushrut S.

    We present our work on analyzing and improving the energy efficiency of multi-axis CNC milling process. Due to the differences in energy consumption behavior, we treat 3- and 5-axis CNC machines separately in our work. For 3-axis CNC machines, we first propose an energy model that estimates the energy requirement for machining a component on a specified 3-axis CNC milling machine. Our model makes machine-specific predictions of energy requirements while also considering the geometric aspects of the machining toolpath. Our model - and the associated software tool - facilitate direct comparison of various alternative toolpath strategies based on their energy-consumption performance. Further, we identify key factors in toolpath planning that affect energy consumption in CNC machining. We then use this knowledge to propose and demonstrate a novel toolpath planning strategy that may be used to generate new toolpaths that are inherently energy-efficient, inspired by research on digital micrography -- a form of computational art. For 5-axis CNC machines, the process planning problem consists of several sub-problems that researchers have traditionally solved separately to obtain an approximate solution. After illustrating the need to solve all sub-problems simultaneously for a truly optimal solution, we propose a unified formulation based on configuration space theory. We apply our formulation to solve a problem variant that retains key characteristics of the full problem but has lower dimensionality, allowing visualization in 2D. Given the complexity of the full 5-axis toolpath planning problem, our unified formulation represents an important step towards obtaining a truly optimal solution. With this work on the two types of CNC machines, we demonstrate that without changing the current infrastructure or business practices, machine-specific, geometry-based, customized toolpath planning can save energy in CNC machining.

  20. Entering the operative correction machining processes CNC

    NASA Astrophysics Data System (ADS)

    Nekrasov, R. Yu; Starikov, A. I.; Lasukov, A. A.

    2015-09-01

    The article describes the solution to the problem of compensation of errors occurring during machining on CNC machines. We propose a method of mathematical modeling of processes diagnostics and control of technological equipment. The results of the diagnosis of the CNC machine, as well as the mathematical model describing the dependence of the positioning error of the executive bodies of operating component of cutting force PZ, in the range of movement OX.

  1. Pavonis Mons Flank

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Context image for PIA03040 Pavonis Mons Flank

    This image shows a portion of the flank of Pavonis Mons. The collapse features at the bottom of the image are related to subsurface tubes that once contained lava.

    Image information: VIS instrument. Latitude 0.6S, Longitude 247.0E. 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  2. Review on CNC-Rapid Prototyping

    NASA Astrophysics Data System (ADS)

    Z, M. Nafis O.; Y, Nafrizuan M.; A, Munira M.; J, Kartina

    2012-09-01

    This article reviewed developments of Computerized Numerical Control (CNC) technology in rapid prototyping process. Rapid prototyping (RP) can be classified into three major groups; subtractive, additive and virtual. CNC rapid prototyping is grouped under the subtractive category which involves material removal from the workpiece that is larger than the final part. Richard Wysk established the use of CNC machines for rapid prototyping using sets of 2½-D tool paths from various orientations about a rotary axis to machine parts without refixturing. Since then, there are few developments on this process mainly aimed to optimized the operation and increase the process capabilities to stand equal with common additive type of RP. These developments include the integration between machining and deposition process (hybrid RP), adoption of RP to the conventional machine and optimization of the CNC rapid prototyping process based on controlled parameters. The article ended by concluding that the CNC rapid prototyping research area has a vast space for improvement as in the conventional machining processes. Further developments and findings will enhance the usage of this method and minimize the limitation of current approach in building a prototype.

  3. An intelligent CNC machine control system architecture

    SciTech Connect

    Miller, D.J.; Loucks, C.S.

    1996-10-01

    Intelligent, agile manufacturing relies on automated programming of digitally controlled processes. Currently, processes such as Computer Numerically Controlled (CNC) machining are difficult to automate because of highly restrictive controllers and poor software environments. It is also difficult to utilize sensors and process models for adaptive control, or to integrate machining processes with other tasks within a factory floor setting. As part of a Laboratory Directed Research and Development (LDRD) program, a CNC machine control system architecture based on object-oriented design and graphical programming has been developed to address some of these problems and to demonstrate automated agile machining applications using platform-independent software.

  4. Arsia Mons Southern Flank

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    The final VIS image of Arsia Mons is located on the southern flank of the volcano adjacent to the NE trending feature. There has been a significant amount of collapse features formed in this region.

    Image information: VIS instrument. Latitude -11.1, Longitude 238.6 East (121.4 West). 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  5. Development of Lathe Attachment for a CNC Machine

    NASA Astrophysics Data System (ADS)

    Roy, V.; Kumar, S.

    2013-04-01

    A lathe attachment has been developed for an existing CNC machine (installed with rapid prototyping attachment) using conceptual design. The CNC machine operates on mechatronic controls and a computer interface called CAMSOFT, and is used as a CNC Lathe after installing the respective attachment to it. The conceptual design phase, starts from an idea and different components of the lathe are designed as attachment using CAD modelling and is followed by fabrication phase. The lathe attachment is successfully developed and is installed to the CNC machine. The working of the CNC Lathe attachment is checked by making some machining operation like turning and thread cutting. The machining operations are successfully done. The CNC machine becomes multifunctional with the presently developed lathe attachment and the existing RP (rapid prototyping) attachment, and can be used accordingly by installing the respective attachment to it. The CNC machine is useful for carrying research work in both the fields, when installed with the appropriate attachment.

  6. CNC Machining Of The Complex Copper Electrodes

    NASA Astrophysics Data System (ADS)

    Popan, Ioan Alexandru; Balc, Nicolae; Popan, Alina

    2015-07-01

    This paper presents the machining process of the complex copper electrodes. Machining of the complex shapes in copper is difficult because this material is soft and sticky. This research presents the main steps for processing those copper electrodes at a high dimensional accuracy and a good surface quality. Special tooling solutions are required for this machining process and optimal process parameters have been found for the accurate CNC equipment, using smart CAD/CAM software.

  7. Volcano Flank Terraces on Mars

    NASA Astrophysics Data System (ADS)

    Byrne, P. K.; van Wyk de Vries, B.; Murray, J. B.; Troll, V. R.

    2008-12-01

    Flank terraces are bulge-like structures that occur on the slopes of at least nine large shield volcanoes on Mars, and three on Earth. Terraces have a convex-upward, convex-outward morphology, with an imbricate "fish scale" stacking pattern in plan. They occur at all elevations, are scale-invariant structures, and have similar proportions to thrust faults on Earth. Suggested mechanisms of formation include elastic self-loading, lithospheric flexure, magma chamber tumescence, flank relaxation, and shallow gravitational slumping. Terrace geometries predicted by most of these mechanisms do not agree with our observations, however. Only lithospheric flexure can fully account for terrace geometry on Mars and Earth, and so is the most likely candidate mechanism for flank terrace formation. To verify this hypothesis, we conducted scaled analogue modelling experiments, and investigated the structures formed during flexure. Cones of a sand-gypsum mix were placed upon a deep layer of silicone gel, to simulate volcanic loads upon viscoelastic Martian crust. Key parameters were varied across our experimental program. In all cases convex topographic structures developed on the cones' flanks, arranged in an imbricate, overlapping plan-view pattern. These structures closely resemble flank terraces observed on Mars, and our results provide for a basic kinematic model of terrace formation. Analogue volcanoes experienced a decrease in upper surface area whilst volume was conserved; the contractional surface strain was accommodated by outward verging, circumferentially striking thrusts. The morphology of experimental structures suggests an orientation of the principal stress axes of σ1 = radial, σ2 = concentric, and σ3 = vertical. Elsewhere (J. B. Murray et al., this volume) we detail the relationship between flank terraces and other structures such as pit craters and gräben, using Ascraeus Mons as a case study. We suggest that terraces may influence the distribution and location

  8. FPGA-based fused smart-sensor for tool-wear area quantitative estimation in CNC machine inserts.

    PubMed

    Trejo-Hernandez, Miguel; Osornio-Rios, Roque Alfredo; de Jesus Romero-Troncoso, Rene; Rodriguez-Donate, Carlos; Dominguez-Gonzalez, Aurelio; Herrera-Ruiz, Gilberto

    2010-01-01

    Manufacturing processes are of great relevance nowadays, when there is a constant claim for better productivity with high quality at low cost. The contribution of this work is the development of a fused smart-sensor, based on FPGA to improve the online quantitative estimation of flank-wear area in CNC machine inserts from the information provided by two primary sensors: the monitoring current output of a servoamplifier, and a 3-axis accelerometer. Results from experimentation show that the fusion of both parameters makes it possible to obtain three times better accuracy when compared with the accuracy obtained from current and vibration signals, individually used. PMID:22319304

  9. FPGA-Based Fused Smart-Sensor for Tool-Wear Area Quantitative Estimation in CNC Machine Inserts

    PubMed Central

    Trejo-Hernandez, Miguel; Osornio-Rios, Roque Alfredo; de Jesus Romero-Troncoso, Rene; Rodriguez-Donate, Carlos; Dominguez-Gonzalez, Aurelio; Herrera-Ruiz, Gilberto

    2010-01-01

    Manufacturing processes are of great relevance nowadays, when there is a constant claim for better productivity with high quality at low cost. The contribution of this work is the development of a fused smart-sensor, based on FPGA to improve the online quantitative estimation of flank-wear area in CNC machine inserts from the information provided by two primary sensors: the monitoring current output of a servoamplifier, and a 3-axis accelerometer. Results from experimentation show that the fusion of both parameters makes it possible to obtain three times better accuracy when compared with the accuracy obtained from current and vibration signals, individually used. PMID:22319304

  10. West Flank Downhole Temperature Data

    DOE Data Explorer

    Doug Blankenship

    2008-03-01

    Downhole temperature data for the three wells inside the West Flank FORGE footprint; 83-11, TCH 74-2 and TCH 48-11. TCH 74-2 and TCH 48-11 were both collected before 1990 and 83-11 was collected in 2009. The are compiled into one spreadsheet for ease of visualization.

  11. A Study on Micro-Machining Technology for the Machining of NiTi: Five-Axis Micro-Milling and Micro Deep-Hole Drilling

    NASA Astrophysics Data System (ADS)

    Biermann, D.; Kahleyss, F.; Krebs, E.; Upmeier, T.

    2011-07-01

    Micro-sized applications are gaining more and more relevance for NiTi-based shape memory alloys (SMA). Different types of micro-machining offer unique possibilities for the manufacturing of NiTi components. The advantage of machining is the low thermal influence on the workpiece. This is important, because the phase transformation temperatures of NiTi SMAs can be changed and the components may need extensive post manufacturing. The article offers a simulation-based approach to optimize five-axis micro-milling processes with respect to the special material properties of NiTi SMA. Especially, the influence of the various tool inclination angles is considered for introducing an intelligent tool inclination optimization algorithm. Furthermore, aspects of micro deep-hole drilling of SMAs are discussed. Tools with diameters as small as 0.5 mm are used. The possible length-to-diameter ratio reaches up to 50. This process offers new possibilities in the manufacturing of microstents. The study concentrates on the influence of the cutting speed, the feed and the tool design on the tool wear and the quality of the drilled holes.

  12. Understanding and Writing G & M Code for CNC Machines

    ERIC Educational Resources Information Center

    Loveland, Thomas

    2012-01-01

    In modern CAD and CAM manufacturing companies, engineers design parts for machines and consumable goods. Many of these parts are cut on CNC machines. Whether using a CNC lathe, milling machine, or router, the ideas and designs of engineers must be translated into a machine-readable form called G & M Code that can be used to cut parts to precise…

  13. Advanced CNC Programming (EZ-CAM). 439-366.

    ERIC Educational Resources Information Center

    Casey, Joe

    This document contains two units for an advanced course in computer numerical control (CNC) for computer-aided manufacturing. It is intended to familiarize students with the principles and techniques necessary to create proper CNC programs using computer software. Each unit consists of an introduction, instructional objectives, learning materials,…

  14. Flank tectonics of Martian volcanoes

    SciTech Connect

    Thomas, P.J. ); Squyres, S.W. ); Carr, M.H. )

    1990-08-30

    On the flanks of Olympus Mons is a series of terraces, concentrically distributed around the caldera. Their morphology and location suggest that they could be thrust faults caused by compressional failure of the cone. In an attempt to understand the mechanism of faulting and the possible influences of the interior structure of Olympus Mons, the authors have constructed a numerical model for elastic stresses within a Martian volcano. In the absence of internal pressurization, the middle slopes of the cone are subjected to compressional stress, appropriate to the formation of thrust faults. These stresses for Olympus Mons are {approximately}250 MPa. If a vacant magma chamber is contained within the cone, the region of maximum compressional stress is extended toward the base of the cone. If the magma chamber is pressurized, extensional stresses occur at the summit and on the upper slopes of the cone. For a filled but unpressurized magma chamber, the observed positions of the faults agree well with the calculated region of high compressional stress. Three other volcanoes on Mars, Ascraeus Mons, Arsia Mons, and Pavonis Mons, possess similar terraces. Extending the analysis to other Martian volcanoes, they find that only these three and Olympus Mons have flank stresses that exceed the compressional failure strength of basalt, lending support to the view that the terraces on all four are thrust faults.

  15. Flank tectonics of Martian volcanoes

    NASA Technical Reports Server (NTRS)

    Thomas, Paul J.; Squyres, Steven W.; Carr, Michael H.

    1990-01-01

    The origin of the numerous terraces on the flanks of the Olympus Mons volcano on Mars, seen on space images to be arranged in a roughly concentric pattern, is investigated. The images of the volcano show that the base of each terrace is marked by a modest but abrupt change in slope, suggesting that these terraces could be thrust faults caused by a compressional failure of the cone. The mechanism of faulting and the possible effect of the interior structure of Olympus Mons was investigated using a numerical model for elastic stresses within a Martian volcano, constructed for that purpose. Results of the analysis supports the view that the terraces on Olympus Mons, as well as on other three Martian volcanoes, including Ascraeus Mons, Arsia Mons, and Pavonis Mons are indeed thrust faults.

  16. Final Report: CNC Micromachines LDRD No.10793

    SciTech Connect

    JOKIEL JR., BERNHARD; BENAVIDES, GILBERT L.; BIEG, LOTHAR F.; ALLEN, JAMES J.

    2003-04-01

    The three-year LDRD ''CNC Micromachines'' was successfully completed at the end of FY02. The project had four major breakthroughs in spatial motion control in MEMS: (1) A unified method for designing scalable planar and spatial on-chip motion control systems was developed. The method relies on the use of parallel kinematic mechanisms (PKMs) that when properly designed provide different types of motion on-chip without the need for post-fabrication assembly, (2) A new type of actuator was developed--the linear stepping track drive (LSTD) that provides open loop linear position control that is scalable in displacement, output force and step size. Several versions of this actuator were designed, fabricated and successfully tested. (3) Different versions of XYZ translation only and PTT motion stages were designed, successfully fabricated and successfully tested demonstrating absolutely that on-chip spatial motion control systems are not only possible, but are a reality. (4) Control algorithms, software and infrastructure based on MATLAB were created and successfully implemented to drive the XYZ and PTT motion platforms in a controlled manner. The control software is capable of reading an M/G code machine tool language file, decode the instructions and correctly calculate and apply position and velocity trajectories to the motion devices linear drive inputs to position the device platform along the trajectory as specified by the input file. A full and detailed account of design methodology, theory and experimental results (failures and successes) is provided.

  17. CNC grinding of valve housing piston holes

    SciTech Connect

    Ashbaugh, F.A.

    1991-11-01

    Grinding has traditionally been used for machining operations requiring close dimensional tolerances and better surface finishes than can be obtained from other metal removal techniques. Using a grinding process for the last metal removal operation, the close tolerances and surface finishes can be easily held while eliminating the adverse conditions from the current metal removal processes. Pre-machined test parts were sent to a machine tool supplier to have the critical inside features of a typical piston bore finish machined using an internal CNC grinder equipped with high-frequency spindles. The piston bore and sealing angle were ground using a standard 120-grit silicon carbide wheel. The wafer step was machined using a solid carbide tool designed and built at Allied-Signal Inc., Kansas City Division (KCD). Six consecutive parts were machined for evaluation. The repeatability on all six parts was within print requirements. The inside corner radii was less than 0.002 in. and the surface finish was 8.2 arithmetical average or better as defined by ANSI B46.1, Surface Texture. Machining parts by this grinding process would eliminate bellmouth, chatter, waviness, and traveler polishing operations. It would produce a superior surface finish, small inside radii, and small easily removable burrs. It would also hold tolerances closer and significantly reduce scrap, rework, rejects, and deviations. 1 fig.

  18. Cytochrome P450 CYP6DA2 regulated by cap 'n'collar isoform C (CncC) is associated with gossypol tolerance in Aphis gossypii Glover.

    PubMed

    Peng, T; Pan, Y; Gao, X; Xi, J; Zhang, L; Yang, C; Bi, R; Yang, S; Xin, X; Shang, Q

    2016-08-01

    Cotton plants accumulate phytotoxins, such as gossypol and related sesquiterpene aldehydes, to resist insect herbivores. The survival of insects exposed to toxic secondary metabolites depends on the detoxification metabolism mediated by limited groups of cytochrome P450. Gossypol has an antibiotic effect on Aphis gossypii, and as the concentrations of gossypol were increased in the present study, the mortality of cotton aphids increased from 4 to 28%. The fecundity of the cotton aphids exposed to gossypol was also significantly reduced compared with the control. The transcriptional levels of CYP6DA2 in cotton aphids were significantly induced when exposed to gossypol, and knockdown of the CYP6DA2 transcripts by RNA interference (RNAi) significantly increased the toxicity of gossypol to cotton aphids. To further understand the gossypol regulatory cascade, the 5'-flanking promoter sequences of CYP6DA2 were isolated with a genome walker, and the promoter was very active and was inducible by gossypol. Co-transfection of the cap 'n' collar isoform C (CncC) and CYP6DA2 promoters dramatically increased the expression of CYP6DA2, and suppression of the CncC transcripts by RNAi significantly decreased the expression levels of CYP6DA2, and significantly increased the toxicity of gossypol to cotton aphids. Thus, the transcriptional regulation of CYP6DA2 involved the transcriptional factor CncC. PMID:27005728

  19. Fidget with Widgets: CNC Activity Introduces the Flatbed Router

    ERIC Educational Resources Information Center

    Tryon, Daniel V.

    2006-01-01

    The computer numerical control (CNC) flatbed router is a powerful tool and a must-have piece of equipment for any technology education program in which students will produce a product--whether it involves Manufacturing, Materials Processing, or any of the vast array of Project Lead the Way courses. This article describes an activity--producing a…

  20. Implementation of Additive Rapid Prototyping on Retrofit CNC Mill

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Freeform fabrication techniques are gaining popularity as a means of making parts. Layered additive methods are associated with rapid prototyping. Many rapid prototyping methods are commercially proprietary and may cost thousands of dollars. Using a retrofit CNC mill for layered fabrication and C...

  1. CNC Turning Technician. A Competency-Based Instructional System.

    ERIC Educational Resources Information Center

    Sloan, Kelly; Hilley, Robert

    This competency-based curriculum guide for instructing students in using computer numerically controlled (CNC) turning machines is one of a series of instructional guides for the machinist field developed in Oklahoma. Although developed jointly with Baxter Technologies Corporation and oriented toward the Baxter Vo-Tec 2000 Future Builder CNC…

  2. Generation of gear tooth surfaces by application of CNC machines

    NASA Technical Reports Server (NTRS)

    Litvin, F. L.; Chen, N. X.

    1994-01-01

    This study will demonstrate the importance of application of computer numerically controlled (CNC) machines in generation of gear tooth surfaces with new topology. This topology decreases gear vibration and will extend the gear capacity and service life. A preliminary investigation by a tooth contact analysis (TCA) program has shown that gear tooth surfaces in line contact (for instance, involute helical gears with parallel axes, worm gear drives with cylindrical worms, etc.) are very sensitive to angular errors of misalignment that cause edge contact and an unfavorable shape of transmission errors and vibration. The new topology of gear tooth surfaces is based on the localization of bearing contact, and the synthesis of a predesigned parabolic function of transmission errors that is able to absorb a piecewise linear function of transmission errors caused by gear misalignment. The report will describe the following topics: description of kinematics of CNC machines with six degrees of freedom that can be applied for generation of gear tooth surfaces with new topology. A new method for grinding of gear tooth surfaces by a cone surface or surface of revolution based on application of CNC machines is described. This method provides an optimal approximation of the ground surface to the given one. This method is especially beneficial when undeveloped ruled surfaces are to be ground. Execution of motions of the CNC machine is also described. The solution to this problem can be applied as well for the transfer of machine tool settings from a conventional generator to the CNC machine. The developed theory required the derivation of a modified equation of meshing based on application of the concept of space curves, space curves represented on surfaces, geodesic curvature, surface torsion, etc. Condensed information on these topics of differential geometry is provided as well.

  3. On the polymorphic and morphological changes of cellulose nanocrystals (CNC-I) upon mercerization and conversion to CNC-II.

    PubMed

    Jin, Ersuo; Guo, Jiaqi; Yang, Fang; Zhu, Yangyang; Song, Junlong; Jin, Yongcan; Rojas, Orlando J

    2016-06-01

    Polymorphic and morphological transformations of cellulosic materials are strongly associated to their properties and applications, especially in the case of emerging nanocelluloses. Related changes that take place upon treatment of cellulose nanocrystals (CNC) in alkaline conditions are studied here by XRD, TEM, AFM, and other techniques. The results indicate polymorphic transformation of CNC proceeds gradually in a certain range of alkali concentrations, i.e. from about 8% to 12.5% NaOH. In such transition alkali concentration, cellulose I and II allomorphs coexists. Such value and range of the transition concentration is strongly interdependent with the crystallite size of CNCs. In addition, it is distinctively lower than that for macroscopic fibers (12-15% NaOH). Transmission electron microscopy and particle sizing reveals that after mercerization CNCs tend to associate. Furthermore, TEMPO-oxidized mercerized CNC reveals the morphology of individual nanocrystal of the cellulose II type, which is composed of some interconnected granular structures. Overall, this work reveals how the polymorphism and morphology of individual CNC change in alkali conditions and sheds light onto the polymorphic transition from cellulose I to II. PMID:27083376

  4. Absolute and geometric parameters of contact binary GW Cnc

    NASA Astrophysics Data System (ADS)

    Gürol, B.; Gökay, G.; Saral, G.; Gürsoytrak, S. H.; Cerit, S.; Terzioğlu, Z.

    2016-07-01

    We present the results of our investigation on the geometrical and physical parameters of the W UMa type binary system GW Cnc. We analyzed the photometric data obtained in 2010 and 2011 at Ankara University Observatory (AUO) and the spectroscopic data obtained in 2010 at TUBITAK National Observatory (TUG) by using the Wilson-Devinney (2013 revision) code to obtain the absolute and geometrical parameters. We derived masses and radii of the eclipsing system to be M1 = 0.257M⊙ , M2 = 0.971M⊙ , R1 = 0.526R⊙ and R2 = 0.961R⊙ with an orbital inclination i(∘) = 83.38 ± 0.25 and we determined the GW Cnc system to be a W-type W UMa over-contact binary with a mass ratio of q = 3.773 ± 0.007 .

  5. ROSSITER-MCLAUGHLIN OBSERVATIONS OF 55 Cnc e

    SciTech Connect

    López-Morales, Mercedes; Rodler, Florian; Dumusque, Xavier; Buchhave, Lars A.; Latham, David W.; Triaud, Amaury H. M. J.; Harutyunyan, Avet; Hoyer, Sergio; Alonso, Roi; Gillon, Michaël; Kaib, Nathan A.; Lovis, Christophe; Pepe, Francesco; Queloz, Didier; Ségransan, Damien; Udry, Stéphane; Raymond, Sean N.; Waldmann, Ingo P.

    2014-09-10

    We present Rossiter-McLaughlin observations of the transiting super-Earth 55 Cnc e collected during six transit events between 2012 January and 2013 November with HARPS and HARPS-N. We detect no radial velocity signal above 35 cm s{sup –1} (3σ) and confine the stellar v sin i {sub *} to 0.2 ± 0.5 km s{sup –1}. The star appears to be a very slow rotator, producing a very low amplitude Rossiter-McLaughlin effect. Given such a low amplitude, the Rossiter-McLaughlin effect of 55 Cnc e is undetected in our data, and any spin-orbit angle of the system remains possible. We also performed Doppler tomography and reach a similar conclusion. Our results offer a glimpse of the capacity of future instrumentation to study low amplitude Rossiter-McLaughlin effects produced by super-Earths.

  6. CNC subaperture polishing process arrangement for microroughness minimisation

    NASA Astrophysics Data System (ADS)

    Prochaska, F.; Matousek, O.; Tomka, D.; Polak, J.; Poláková, I.

    2015-01-01

    The aim of this study was to determine the optimal subaperture polishing procedure for aspherical surfaces on the Optotech MCP 250 CNC machine. Due to the fact that the CNC subaperture polishing process runs along well defined paths, certain frequencies develop on the polished surface, which can be limiting for the resulting microroughness. A proper sequence of polishing steps in different tool motion control modes can minimize these frequencies and help to substantially reduce microroughness. In this context, various tool motion control modes ("Spiral spindle mode", "Spiral axis mode" and "Raster mode") in combination with different tools were tested. The resulting microroughness values were observed in the defined mid-frequency and high-frequency areas. The best results, i.e. the lowest microroughness values were obtained using a combination of the processes "Ball spiral axis mode", "FEM raster mode", "spiral spindle 2D FEM correction mode" and "AFJ spiral axis mode"

  7. Motion Simulation Analysis of Rail Weld CNC Fine Milling Machine

    NASA Astrophysics Data System (ADS)

    Mao, Huajie; Shu, Min; Li, Chao; Zhang, Baojun

    CNC fine milling machine is a new advanced equipment of rail weld precision machining with high precision, high efficiency, low environmental pollution and other technical advantages. The motion performance of this machine directly affects its machining accuracy and stability, which makes it an important consideration for its design. Based on the design drawings, this article completed 3D modeling of 60mm/kg rail weld CNC fine milling machine by using Solidworks. After that, the geometry was imported into Adams to finish the motion simulation analysis. The displacement, velocity, angular velocity and some other kinematical parameters curves of the main components were obtained in the post-processing and these are the scientific basis for the design and development for this machine.

  8. Research and exploitation of CNC laser manufacturing online monitoring system based on OpenGL

    NASA Astrophysics Data System (ADS)

    Wang, Gang; Hu, Shengsun; Wang, Mingjian; Ding, Wei; Zhao, Jie

    2010-12-01

    CNC manufacturing online monitoring technology is a significant method to improve the processing quality and achieve an important part of intelligent processing. Based on OpenGL 3D graphics technology, a Computer Numerical Control (CNC ) Laser Manufacturing 3D model is established; based on the model and the powerful ability of OpenGL, a CNC manufacturing on-line monitoring system is developed so as to achieve the ability of CNC remote real-time online monitoring in different working locations. Remote real-time online monitoring of different position of the CNC is realized. The online monitoring scope of the CNC is enlarged, with more flexibility to meet the demands of practical application, meanwhile the cost of hardware investment is greatly reduced.

  9. Integrated CAD/CAM/CNC system based on STEP-NC and intelligent manufacturing

    NASA Astrophysics Data System (ADS)

    Du, Juan; Tian, Xitian; Zhang, Zhenming; Xu, Jianxin; Zhu, Mingquan

    2005-12-01

    In order to realize bi-direction exchange of information and knowledge sharing between CAD/CAM systems and CNC machines, a method of information integration was proposed based on process data model and STEP-NC neutral file. A frame of integrated CAD/CAM/CNC systems was established, and the key integration techniques including process data modeling based on XML form and automatic feature recognition were studied. Since the STEP-NC based CNC (STEP- CNC) system can undertake various intelligent functions that cannot be performed by the conventional CNC based on ISO 6983, the intelligent manufacturing functions of STEP- CNC system was also discussed. The presented methodology combining with the modern net and communication technologies provides an effective means for developing intelligent, integrated manufacturing systems for the 21 century.

  10. Volcano Flank Structures on Earth and Mars

    NASA Astrophysics Data System (ADS)

    van Wyk de Vries, B.; Byrne, P. K.; Mathieu, L.; Murray, J. B.; Troll, V. R.

    2007-12-01

    Shield volcanoes on Earth and Mars share common features, including calderas and pit crater chains. A set of structures present on the sides of several of the large shields on Mars are not regarded as having Earth analogues, however. Flank terraces are topographically subtle structures, characterised by a gentle convex profile and a distinctive "fish scale" imbricate distribution pattern. Magma chamber inflation, lithospheric flexure, flank relaxation, or gravitational slumping have been suggested as terrace formation mechanisms. Terraces on both Mars and Earth are clearly visible only in slope maps, and may thus escape visual detection in the field. We show that both Mauna Loa (Hawaii) and Etna (Sicily) display the same characteristic "fish scale" terrace pattern. This pattern delineates structures that we contend are terrestrial flank terraces. Heterogeneities in volcano geometry, due to buttressing or extension, result in terrace distributions that are not as evenly circumferential as those on Mars. Plan and cross-sectional profiles, however, parallel those of the Martian structures. These structures may also be present on Alayta (Ethiopia), Santa Cruz (Galapagos), and Tendürek Dagi (Turkey). Another type of structure, larger and steeper than flank terraces but sharing a similar plan-view morphology, is also present on Mauna Lau and Etna. These "flank bulges" appear to correlate with structures on Piton de la Fournaise (La Réunion), Cosiguina (Nicaragua), and Karthala (Comoros) on Earth, and Apollinaris Patera and Tharsis Tholus on Mars. Elsewhere (Paul K. Byrne et al., this volume) we argue that lithospheric flexure is a likely formation mechanism for Martian terraces. Flexure is active beneath Mauna Loa, and possibly under Etna, and so may also be responsible for terrestrial flank terraces. Scaled analogue models suggest that the larger flank bulges are due to magma intrusions derived from large chambers within these edifices. There is thus a strong

  11. CNC Turning Center Advanced Operations. Computer Numerical Control Operator/Programmer. 444-332.

    ERIC Educational Resources Information Center

    Skowronski, Steven D.; Tatum, Kenneth

    This student guide provides materials for a course designed to introduce the student to the operations and functions of a two-axis computer numerical control (CNC) turning center. The course consists of seven units. Unit 1 presents course expectations and syllabus, covers safety precautions, and describes the CNC turning center components, CNC…

  12. Researches Regarding The Circular Interpolation Algorithms At CNC Laser Cutting Machines

    NASA Astrophysics Data System (ADS)

    Tîrnovean, Mircea Sorin

    2015-09-01

    This paper presents an integrated simulation approach for studying the circular interpolation regime of CNC laser cutting machines. The circular interpolation algorithm is studied, taking into consideration the numerical character of the system. A simulation diagram, which is able to generate the kinematic inputs for the feed drives of the CNC laser cutting machine is also presented.

  13. Intellectual Control System of Processing on CNC Machines

    NASA Astrophysics Data System (ADS)

    Nekrasov, R. Y.; Lasukov, A. A.; Starikov, A. I.; Soloviev, I. V.; Bekareva, O. V.

    2016-04-01

    Scientific and technical progress makes great demands for quality of engineering production. The priority is to ensure metalworking equipment with required dimensional accuracy during the entire period of operation at minimum manufacturing costs. In article considered the problem of increasing of accuracy of processing products on CNC. The authors offers a solution to the problem by providing compensating adjustment in the trajectory of the cutting tool and machining mode. The necessity of creation of mathematical models of processes behavior in an automated technological system operations (OATS). Based on the research, authors have proposed a generalized diagram of diagnosis and input operative correction and approximate mathematical models of individual processes of diagnosis.

  14. Integration, calibration, and testing of resistor array dynamic infrared scene projector on the outer axis of a five-axis flight motion simulator for real-time hardware-in-the-loop simulations

    NASA Astrophysics Data System (ADS)

    Goldsmith, George C., II; Amick, Mary Amenda; Jones, Lawrence E.

    1996-05-01

    The Air Force Development Test Center's (AFDTC) Guided Weapons Evaluation Facility (GWEF), is designed to test guided munitions performance using Hardware-In-the-Loop simulations. Evaluation of imaging infrared guided munitions requires the generation and projection of complex infrared (IR) `fly-in' scenes to the unit under test which is mounted to a flight motion simulator. Members of AFDTC's 46 Test Wing and Avionics Systems Command's Wright Labs have teamed to develop and integrate this capability within the GWEF and Wright Lab's Kinetic Kill Hardware-In-the-Loop Simulation (KHILS) facility. The major Hardware-In-the-Loop (HIL) components for the GWEF include an IR scene generator, an IR projector, a five axis flight motion simulator (FMS), a 6 degree of freedom missile flight simulation, and the opto- mechanical interface to mount the projector onto the 5 axis FMS. GWEF's unique HIL solution is utilizing the 512 X 512 resistor array technology developed by KHILS, and off- the-shelf state-of-the-art scene generation computer, FMS, and optics. Details on this in-house development effort include acquisition and configuration/integration issues, thermal information to radiance bandpass output validation, IR scene generation and frame latency, generated IR scene input to projected output calibration, and simulation guidance from launch to impact verification. This capability has been successfully integrated into the GWEF, meeting a March 1996 HIL test.

  15. Understanding Etna flank instability through numerical models

    NASA Astrophysics Data System (ADS)

    Apuani, Tiziana; Corazzato, Claudia; Merri, Andrea; Tibaldi, Alessandro

    2013-02-01

    As many active volcanoes, Mount Etna shows clear evidence of flank instability, and different mechanisms were suggested to explain this flank dynamics, based on the recorded deformation pattern and character. Shallow and deep deformations, mainly associated with both eruptive and seismic events, are concentrated along recognised fracture and fault systems, mobilising the eastern and south-eastern flank of the volcano. Several interacting causes were postulated to control the phenomenon, including gravity force, magma ascent along the feeding system, and a very complex local and/or regional tectonic activity. Nevertheless, the complexity of such dynamics is still an open subject of research and being the volcano flanks heavily urbanised, the comprehension of the gravitative dynamics is a major issue for public safety and civil protection. The present research explores the effects of the main geological features (in particular the role of the subetnean clays, interposed between the Apennine-Maghrebian flysch and the volcanic products) and the role of weakness zones, identified by fracture and fault systems, on the slope instability process. The effects of magma intrusions are also investigated. The problem is addressed by integrating field data, laboratory tests and numerical modelling. A bi- and tri-dimensional stress-strain analysis was performed by a finite difference numerical code (FLAC and FLAC3D), mainly aimed at evaluating the relationship among geological features, volcano-tectonic structures and magmatic activity in controlling the deformation processes. The analyses are well supported by dedicated structural-mechanical field surveys, which allowed to estimate the rock mass strength and deformability parameters. To take into account the uncertainties which inevitably occur in a so complicated model, many efforts were done in performing a sensitivity analysis along a WNW-ESE section crossing the volcano summit and the Valle del Bove depression. This was

  16. MULTIBAND PHOTOMETRIC AND SPECTROSCOPIC ANALYSIS OF HV Cnc

    SciTech Connect

    Gökay, G.; Gürol, B.; Derman, E.

    2013-11-01

    In this paper, radial velocity and VI- and JHK{sub S} - (Two Micron All Sky Survey) band photometric data of the detached system HV Cnc have been analyzed. The primary component of HV Cnc, which is a member of the M67 cluster, is suspected to be either a blue straggler or turn-off star. The system is a single-lined spectroscopic binary and its light curve shows a total eclipse. Spectroscopic observations of the system revealed the third component, which shows contribution to the total light of the system. Light curve and radial velocity data have been analyzed using the Wilson-Devinney (W-D) code and JHK{sub S} filter definitions computed for the W-D code in this work. Our analysis shows that the mass and radius of the primary and secondary components are 1.31 M {sub ☉}, 0.52 M {sub ☉}, 1.87 R {sub ☉}, and 0.48 R {sub ☉}, respectively. All results are compared with previously published literature values and discussed.

  17. TX Cnc AS A MEMBER OF THE PRAESEPE OPEN CLUSTER

    SciTech Connect

    Zhang, X. B.; Deng, L.; Lu, P.

    2009-08-15

    We present B-, V-, and I-band CCD photometry of the W UMa-type binary system TX Cnc, which is a member star of the Praesepe open cluster. Based on the observations, new ephemeris and a revised photometric solution of the binary system were derived. Combined with the results of the radial velocity solution contributed by Pribulla et al., the absolute parameters of the system were determined. The mass, radius, and luminosity of the primary component are derived to be 1.35 {+-} 0.02 M {sub sun}, 1.27 {+-} 0.04 R {sub sun}, and 2.13 {+-} 0.11 L {sub sun}. Those for the secondary star are computed as 0.61 {+-} 0.01 M {sub sun}, 0.89 {+-} 0.03 R {sub sun}, and 1.26 {+-} 0.07 L {sub sun}, respectively. Based on these results, a distance modulus of (m - M) {sub V} = 6.34 {+-} 0.05 is determined for the star. It confirms the membership of TX Cnc to the Praesepe open cluster. The evolutionary status and the physical nature of the binary system are discussed compared with the theoretical model.

  18. CNC water-jet machining and cutting center

    SciTech Connect

    Bartlett, D.C.

    1991-09-01

    CNC water-jet machining was investigated to determine the potential applications and cost-effectiveness that would result by establishing this capability in the engineering shops of Allied-Signal Inc., Kansas City Division (KCD). Both conductive and nonconductive samples were machined at KCD on conventional machining equipment (a three-axis conversational programmed mill and a wire electrical discharge machine) and on two current-technology water-jet machines at outside vendors. These samples were then inspected, photographed, and evaluated. The current-technology water-jet machines were not as accurate as the conventional equipment. The resolution of the water-jet equipment was only {plus minus}0.005 inch, as compared to {plus minus}0.0002 inch for the conventional equipment. The principal use for CNC water-jet machining would be as follows: Contouring to near finished shape those items made from 300 and 400 series stainless steels, titanium, Inconel, aluminum, glass, or any material whose fabrication tolerance is less than the machine resolution of {plus minus}0.005 inch; and contouring to finished shape those items made from Kevlar, rubber, fiberglass, foam, aluminum, or any material whose fabrication specifications allow the use of a machine with {plus minus}0.005 inch tolerance. Additional applications are possible because there is minimal force generated on the material being cut and because the water-jet cuts without generating dust. 12 figs.

  19. West Flank Coso, CA FORGE Seismic Reflection

    DOE Data Explorer

    Doug Blankenship

    2016-05-16

    PDFs of seismic reflection profiles 101,110, 111 local to the West Flank FORGE site. 45 line kilometers of seismic reflection data are processed data collected in 2001 through the use of vibroseis trucks. The initial analysis and interpretation of these data was performed by Unruh et al. (2001). Optim processed these data by inverting the P-wave first arrivals to create a 2-D velocity structure. Kirchhoff images were then created for each line using velocity tomograms (Unruh et al., 2001).

  20. [Flank pain in renal and ureteral calculus].

    PubMed

    Pedersen, Katja Venborg; Drewes, Asbjørn Mohr; Osther, Palle Jørn Sloth

    2011-02-14

    Flank pain is common and often associated with stone colics. Similar pain characteristics can, however, be observed in other diseases. Stone colics have all the characteristics of visceral pain. The pain is diffuse, often referred to the body wall and accompanied by autonomic reflexes. In patients with recurrent stones, the colics may be more intense due to sensitisation of the nervous system. Furthermore, painful diseases in the reproductive organs can enhance stone colics. Non-steroidal anti-inflammatory drugs are the first choice for stone colics because they act by reducing the renal pelvic pressure. PMID:21320415

  1. West Flank Coso, CA FORGE Magnetotelluric Inversion

    DOE Data Explorer

    Doug Blankenship

    2016-05-16

    The Coso Magnetotelluric (MT) dataset of which the West Flank FORGE MT data is a subset, was collected by Schlumberger / WesternGeco and initially processed by the WesternGeco GeoSolutions Integrated EM Center of Excellence in Milan, Italy. The 2011 data was based on 99 soundings that were centered on the West Flank geothermal prospect. The new soundings along with previous data from 2003 and 2006 were incorporated into a 3D inversion. Full impedance tensor data were inverted in the 1-3000 Hz range. The modelling report notes several noise sources, specifically the DC powerline that is 20,000 feet west of the survey area, and may have affected data in the 0.02 to 10 Hz range. Model cell dimensions of 450 x 450 x 65 feet were used to avoid computational instability in the 3D model. The fit between calculated and observed MT values for the final model run had an RMS value of 1.807. The included figure from the WesternGeco report shows the sounding locations from the 2011, 2006 and 2003 surveys.

  2. [Excruciating flank pain: "acute renal colic"].

    PubMed

    Thomas, A; Andrianne, R

    2004-04-01

    The classic presentation of acute renal colic is the sudden onset of very severe pain in the flank primarily caused by the acute ureteral obstruction. The diagnosis is often made on clinical symptoms only, although confirmatory exams are generally performed because many others significant disorders may present with symptom of flank pain that mimics renal colic. Life threatening emergency such as abdominal aortic aneurysm must be ruled out. While non contrast CT has become the standard imaging modality, in some situations, a plain abdominal radiograph associated with a renal ultrasound or a contrast study such as intravenous pyelogram may be preferred. Hematuria is frequently present on urine analysis. The usual therapy represented by analgesic and nonsteroidal anti-inflammatory drugs should be started as soon as possible. Size and location of the stone are the most important predictors of spontaneous passage. Uncontrolled pain by medical therapy, fever, oligo-anuria suggest complicated stone disease. Such conditions require emergency treatment by drainage or stone extraction. Although recurrent stone rate is important, extensive metabolic explorations are not recommended after an uncomplicated first episode. Nevertheless fluid intake is encouraged and a stone chemical analysis should be performed whenever possible. PMID:15182032

  3. Modeling of tool path for the CNC sheet cutting machines

    NASA Astrophysics Data System (ADS)

    Petunin, Aleksandr A.

    2015-11-01

    In the paper the problem of tool path optimization for CNC (Computer Numerical Control) cutting machines is considered. The classification of the cutting techniques is offered. We also propose a new classification of toll path problems. The tasks of cost minimization and time minimization for standard cutting technique (Continuous Cutting Problem, CCP) and for one of non-standard cutting techniques (Segment Continuous Cutting Problem, SCCP) are formalized. We show that the optimization tasks can be interpreted as discrete optimization problem (generalized travel salesman problem with additional constraints, GTSP). Formalization of some constraints for these tasks is described. For the solution GTSP we offer to use mathematical model of Prof. Chentsov based on concept of a megalopolis and dynamic programming.

  4. Design and performance of a small precision CNC turning machine

    SciTech Connect

    Donaldson, R.R.; Thompson, D.C.

    1986-02-26

    This paper describes the design of a CNC turning machine that is capable of machining workpieces up to 100 mm in diameter with a high contour accuracy and a very low surface roughness. Two nearly identical machines have been built and put into operation using this design, one for serial parts manufacture and the other for research into improving the accuracy of single-point machining; information based on this operational experience is also presented. The first machine has demonstrated an accuracy of 0.1 ..mu..m peak-to-valley on contoured workpieces, while the second machine has produced surface roughnesses of 1 nm rms in flat facing of electroless nickel with a diamond tool.

  5. Hybridization Capture Using Short PCR Products Enriches Small Genomes by Capturing Flanking Sequences (CapFlank)

    PubMed Central

    Tsangaras, Kyriakos; Wales, Nathan; Sicheritz-Pontén, Thomas; Rasmussen, Simon; Michaux, Johan; Ishida, Yasuko; Morand, Serge; Kampmann, Marie-Louise; Gilbert, M. Thomas P.; Greenwood, Alex D.

    2014-01-01

    Solution hybridization capture methods utilize biotinylated oligonucleotides as baits to enrich homologous sequences from next generation sequencing (NGS) libraries. Coupled with NGS, the method generates kilo to gigabases of high confidence consensus targeted sequence. However, in many experiments, a non-negligible fraction of the resulting sequence reads are not homologous to the bait. We demonstrate that during capture, the bait-hybridized library molecules add additional flanking library sequences iteratively, such that baits limited to targeting relatively short regions (e.g. few hundred nucleotides) can result in enrichment across entire mitochondrial and bacterial genomes. Our findings suggest that some of the off-target sequences derived in capture experiments are non-randomly enriched, and that CapFlank will facilitate targeted enrichment of large contiguous sequences with minimal prior target sequence information. PMID:25275614

  6. Rapid deformation of the south flank of Kilauea Volcano, Hawaii

    USGS Publications Warehouse

    Owen, S.; Segall, P.; Freymueller, Jeffrey T.; Miklius, Asta; Denlinger, R.; Arnadottir, T.; Sako, M.; Burgmann, R.

    1995-01-01

    The south flank of Kilauea volcano has experienced two large [magnitude (M) 7.2 and M 6.1] earthquakes in the past two decades. Global Positioning System measurements conducted between 1990 and 1993 reveal seaward displacements of Kilauea's central south flank at rates of up to about 10 centimeters per year. In contrast, the northern side of the volcano and the distal ends of the south flank did not displace significantly. The observations can be explained by slip on a low-angle fault beneath the south flank combined with dilation deep within Kilauea's rift system, both at rates of at least 15 centimeters per year.

  7. Shared and service-oriented CNC machining system for intelligent manufacturing process

    NASA Astrophysics Data System (ADS)

    Li, Yao; Liu, Qiang; Tong, Ronglei; Cui, Xiaohong

    2015-11-01

    To improve efficiency, reduce cost, ensure quality effectively, researchers on CNC machining have focused on virtual machine tool, cloud manufacturing, wireless manufacturing. However, low level of information shared among different systems is a common disadvantage. In this paper, a machining database with data evaluation module is set up to ensure integrity and update. An online monitoring system based on internet of things and multi-sensors "feel" a variety of signal features to "percept" the state in CNC machining process. A high efficiency and green machining parameters optimization system "execute" service-oriented manufacturing, intelligent manufacturing and green manufacturing. The intelligent CNC machining system is applied in production. CNC machining database effectively shares and manages process data among different systems. The prediction accuracy of online monitoring system is up to 98.8% by acquiring acceleration and noise in real time. High efficiency and green machining parameters optimization system optimizes the original processing parameters, and the calculation indicates that optimized processing parameters not only improve production efficiency, but also reduce carbon emissions. The application proves that the shared and service-oriented CNC machining system is reliable and effective. This research presents a shared and service-oriented CNC machining system for intelligent manufacturing process.

  8. Cellulose nanocrystals (CNC) as carriers for a spirooxazine dye and its effect on photochromic efficiency.

    PubMed

    Sun, Bo; Hou, Qingxi; He, Zhibin; Liu, Zehua; Ni, Yonghao

    2014-10-13

    Nanocrystalline cellulose (CNC) as a renewable/sustainable material, has received much attention. Herein we studied CNC as carriers for a hydrophobic spirooxazine (SO)-based dye, 1,3-dihydro-1,3,3-trimethylspiro[2H-indole-2,3'-[3H]naphtha[2,1-b][1,4]oxazine], which may have potential applications in reversible memory photo-devices, textiles, photo-sensitive paper coatings, and inkjet printing inks. Due to the high cost and water-insolubility of this dye, it is desirable to improve its coloration efficiency and water-dispersibility. The experimental approach was to use CNC as carriers for the SO dye, thus obtaining a stable photochromic dye in aqueous systems. Transmission electron microscope (TEM) observation confirmed that the SO dye adsorbed on the surface of the CNC, which functioned as carriers for the photochromic dye. An impregnation process was adopted to anchor the dye onto cellulosic paper. It was found that the use of CNC resulted in a significant improvement in the SO coloration efficiency. The color stability and fatigue resistance were also studied. The use of CNC as carriers for a hydrophobic compound, its enhancement of associated properties, and its subsequent application were demonstrated. PMID:25037370

  9. Positioning the actual interference fringe pattern on the tooth flank in measuring gear tooth flanks by laser interferometry

    NASA Astrophysics Data System (ADS)

    Fang, Suping; Wang, Leijie; Liu, Shiqiao; Komori, Masaharu; Kubo, Aizoh

    2011-05-01

    In measuring form deviation of gear tooth flanks by laser interferometry, the collected interference fringe pattern (IFP) is badly distorted, in the case of shape, relative to the actual tooth flank. Meanwhile, a clear and definite mapping relationship between the collected IFP and the actual tooth flank is indispensable for both transforming phase differences into deviation values and positioning the measurement result on the actual tooth flank. In order to solve these problems, this paper proposes a method using the simulation tooth image as a bridge connecting the actual tooth flank and the collected IFP. The mapping relationship between the simulation tooth image and the actual tooth flank has been obtained by ray tracing methods [Fang et al., Appl. Opt. 49(33), 6409-6415 (2010)]. This paper mainly discusses how to build the relationship between the simulation tooth image and the collected IFP by using a matching algorithm of two characteristic point sets. With the combination of the two above-mentioned assistant mapping relationships, the mapping relationship between the collected IFP and the actual tooth flank can be built; the collected IFP can be positioned on the actual tooth flank. Finally, the proposed method is employed in a measurement of the form deviation of a gear tooth flank and the result proves the feasibility of the proposed method.

  10. West Flank Coso, CA FORGE ArcGIS data 2

    DOE Data Explorer

    Doug Blankenship

    2016-03-01

    archive of ArcGIS data from the West Flank FORGE site located in Coso, California. Archive contains: 8 shapefiles polygon of the 3D geologic model polylines of the traces 3D modeled faults polylines of the fault traces from Duffield and Bacon, 1980 polygon of the West Flank FORGE site polylines of the traces of the geologic cross-sections (cross-sections in a separate archive in the GDR) polylines of the traces of the seismic reflection profiles through and adjacent to the West Flank site (seismic reflection profiles in a separate archive in the GDR) points of the well collars in and around the West Flank site polylines of the surface expression of the West Flank well paths

  11. Systematics for checking geometric errors in CNC lathes

    NASA Astrophysics Data System (ADS)

    Araújo, R. P.; Rolim, T. L.

    2015-10-01

    Non-idealities presented in machine tools compromise directly both the geometry and the dimensions of machined parts, generating distortions in the project. Given the competitive scenario among different companies, it is necessary to have knowledge of the geometric behavior of these machines in order to be able to establish their processing capability, avoiding waste of time and materials as well as satisfying customer requirements. But despite the fact that geometric tests are important and necessary to clarify the use of the machine correctly, therefore preventing future damage, most users do not apply such tests on their machines for lack of knowledge or lack of proper motivation, basically due to two factors: long period of time and high costs of testing. This work proposes a systematics for checking straightness and perpendicularity errors in CNC lathes demanding little time and cost with high metrological reliability, to be used on factory floors of small and medium-size businesses to ensure the quality of its products and make them competitive.

  12. The design of an ultra-precision CNC measuring machine

    SciTech Connect

    Thompson, D.C.

    1989-01-01

    A specialized ultra-precision CNC measuring machine is being developed to provide an inspection capability compatible with existing precision turning machines. The instrument is to be applied to the inspection of the inner and outer surfaces of hemispherical shells and other axisymmetric parts, with diameters of up to 400 mm. The overall accuracy of the machine operating in continuous path contouring mode is to be less than 0.75 micrometre (p-v) per surface, including both instrument and process-related errors. In addition, an accuracy of 1.75 micrometres is required for the inspection of wall thickness on some categories of parts, which in some instances may be distorted by gravity loading. This latter requirement dictates a single setup for the inspection of inner and outer surfaces, and effectively eliminates a standard Coordinate Measuring Machine (CMM) configuration for the new gauge. The new instrument is known as the Certification of Process (COP) Gauge. 9 refs., 5 figs., 2 tabs.

  13. Continuous tone printing in silicone from CNC milled matrices

    NASA Astrophysics Data System (ADS)

    Hoskins, S.; McCallion, P.

    2014-02-01

    Current research at the Centre for Fine Print Research (CFPR) at the University of the West of England, Bristol, is exploring the potential of creating coloured pictorial imagery from a continuous tone relief surface. To create the printing matrices the research team have been using CNC milled images where the height of the relief image is dictated by creating a tone curve and then milling this curve into a series of relief blocks from which the image is cast in a silicone ink. A translucent image is cast from each of the colour matrices and each colour is assembled - one on top of another - resulting is a colour continuous tone print, where colour tone is created by physical depth of colour. This process is a contemporary method of continuous tone colour printing based upon the Nineteenth Century black and white printing process of Woodburytype as developed by Walter Bentley Woodbury in 1865. Woodburytype is the only true continuous tone printing process invented, and although its delicate and subtle surfaces surpassed all other printing methods at the time. The process died out in the late nineteenth century as more expedient and cost effective methods of printing prevailed. New research at CFPR builds upon previous research that combines 19th Century Photomechanical techniques with digital technology to reappraise the potential of these processes.

  14. Spatial augmented reality on industrial CNC-machines

    NASA Astrophysics Data System (ADS)

    Olwal, Alex; Gustafsson, Jonny; Lindfors, Christoffer

    2008-02-01

    In this work we present how Augmented Reality (AR) can be used to create an intimate integration of process data with the workspace of an industrial CNC (computer numerical control) machine. AR allows us to combine interactive computer graphics with real objects in a physical environment - in this case, the workspace of an industrial lathe. ASTOR is an autostereoscopic optical see-through spatial AR system, which provides real-time 3D visual feedback without the need for user-worn equipment, such as head-mounted displays or sensors for tracking. The use of a transparent holographic optical element, overlaid onto the safety glass, allows the system to simultaneously provide bright imagery and clear visibility of the tool and workpiece. The system makes it possible to enhance visibility of occluded tools as well as to visualize real-time data from the process in the 3D space. The graphics are geometrically registered with the workspace and provide an intuitive representation of the process, amplifying the user's understanding and simplifying machine operation.

  15. ADAM13 cleavage of cadherin-11 promotes CNC migration independently of the homophilic binding site.

    PubMed

    Abbruzzese, Genevieve; Becker, Sarah F; Kashef, Jubin; Alfandari, Dominique

    2016-07-15

    The cranial neural crest (CNC) is a highly motile population of cells that is responsible for forming the face and jaw in all vertebrates and perturbing their migration can lead to craniofacial birth defects. Cell motility requires a dynamic modification of cell-cell and cell-matrix adhesion. In the CNC, cleavage of the cell adhesion molecule cadherin-11 by ADAM13 is essential for cell migration. This cleavage generates a shed extracellular fragment of cadherin-11 (EC1-3) that possesses pro-migratory activity via an unknown mechanism. Cadherin-11 plays an important role in modulating contact inhibition of locomotion (CIL) in the CNC to regulate directional cell migration. Here, we show that while the integral cadherin-11 requires the homophilic binding site to promote CNC migration in vivo, the EC1-3 fragment does not. In addition, we show that increased ADAM13 activity or expression of the EC1-3 fragment increases CNC invasiveness in vitro and blocks the repulsive CIL response in colliding cells. This activity requires the presence of an intact homophilic binding site on the EC1-3 suggesting that the cleavage fragment may function as a competitive inhibitor of cadherin-11 adhesion in CIL but not to promote cell migration in vivo. PMID:26206614

  16. Synthesis of chemical cross-linked gelatin hydrogel reinforced with cellulose nanocrystals (CNC)

    NASA Astrophysics Data System (ADS)

    Yin, Ooi Shok; Ahmad, Ishak; Amin, Mohd. Cairul Iqbal Mohd

    2014-09-01

    A novel method was performed to obtain hydrogel with superior sensitivity towards changes in pH and temperature by incorporation of CNC into gelatin based hydrogel. Glutaraldehyde was used as cross-linker due to its high chemical reactivity towards NH2 group on gelatin. Different ratio of gelatin / CNC hydrogel was produced in order to study the effects of CNC towards the swelling behaviour of hydrogel at different pH and temperature. Swelling tests were performed at different pH range from pH 3 to pH 11. Temperature swelling tests were performed at 25 °C and 37 °C. The hydrogel showed impressive pH sensitivity and maximum swelling was obtained at pH 3. Higher swelling ratio was observed at higher temperature. SEM micrographs showed that the pore size of hydrogel decreased with increasing CNC content due to formation of more rigid hydrogel structure. The characteristics of the hydrogel to respond to different pH and temperature suggest that gelatin / CNC hydrogel are promising candidates to be developed as drug carrier.

  17. Repurposing mainstream CNC machine tools for laser-based additive manufacturing

    NASA Astrophysics Data System (ADS)

    Jones, Jason B.

    2016-04-01

    The advent of laser technology has been a key enabler for industrial 3D printing, known as Additive Manufacturing (AM). Despite its commercial success and unique technical capabilities, laser-based AM systems are not yet able to produce parts with the same accuracy and surface finish as CNC machining. To enable the geometry and material freedoms afforded by AM, yet achieve the precision and productivity of CNC machining, hybrid combinations of these two processes have started to gain traction. To achieve the benefits of combined processing, laser technology has been integrated into mainstream CNC machines - effectively repurposing them as hybrid manufacturing platforms. This paper reviews how this engineering challenge has prompted beam delivery innovations to allow automated changeover between laser processing and machining, using standard CNC tool changers. Handling laser-processing heads using the tool changer also enables automated change over between different types of laser processing heads, further expanding the breadth of laser processing flexibility in a hybrid CNC. This paper highlights the development, challenges and future impact of hybrid CNCs on laser processing.

  18. ADAM13 cleavage of cadherin-11 promotes CNC migration independently of the homophilic binding site

    PubMed Central

    Kashef, Jubin; Alfandari, Dominique

    2015-01-01

    The cranial neural crest (CNC) is a highly motile population of cells that is responsible for forming the face and jaw in all vertebrates and perturbing their migration can lead to craniofacial birth defects. Cell motility requires a dynamic modification of cell–cell and cell-matrix adhesion. In the CNC, cleavage of the cell adhesion molecule cadherin-11 by ADAM13 is essential for cell migration. This cleavage generates a shed extracellular fragment of cadherin-11 (EC1-3) that possesses pro-migratory activity via an unknown mechanism. Cadherin-11 plays an important role in modulating contact inhibition of locomotion (CIL) in the CNC to regulate directional cell migration. Here, we show that while the integral cadherin-11 requires the homophilic binding site to promote CNC migration in vivo, the EC1-3 fragment does not. In addition, we show that increased ADAM13 activity or expression of the EC1-3 fragment increases CNC invasiveness in vitro and blocks the repulsive CIL response in colliding cells. This activity requires the presence of an intact homophilic binding site on the EC1-3 suggesting that the cleavage fragment may function as a competitive inhibitor of cadherin-11 adhesion in CIL but not to promote cell migration in vivo. PMID:26206614

  19. Integrated study to define the hazard of the unstable flanks of Mt. Etna: the Italian DPC-INGV FLANK Project

    NASA Astrophysics Data System (ADS)

    Acocella, Valerio; Puglisi, Giuseppe

    2010-05-01

    Volcanoes are often characterized by unstable flanks. The eastern and south-eastern flanks of Mt. Etna (Italy) have shown repeated evidence of instability in the recent past. The extent and frequency of these processes varies widely, from nearly continuous creep-like movements of specific portions of the flank to the rarer slip of the entire eastern sector, involving also the off-shore portion. Estimated slip rates may vary enormously, from mm/yr to m/week. The most dramatic instability events are associated with major eruptions and shallow seismic activity, as during 2002-2003, posing a serious hazard to the inhabited flanks of the volcano. The Italian Department of Civil Defense (DPC), with the National Institute of Geophysics and Volcanology (INGV), as well as with the involvement of Italian Universities and other Research Institutes, has launched a 2-years project (may 2008-may 2010) devoted to minimize the hazard deriving from the instability of the Etna flanks. This multidisciplinary project embraces geological, geophysical, volcanological, modeling and hazard studies, both on the on-shore and the off-shore portions of the E and SE flanks of the volcano. Indeed, the main aims are to define: (a) the 3D geometry of the collapsing sector(s); (b) the relationships between flank movement and volcanic and seismic activity; (c) the hazard related to the flank instability. The collected data populate a GIS database implemented according the WoVo rules. This project represents the first attempt, at least in Europe, to use an integrated approach to minimize the hazard deriving from flank instability in a volcano. Here we briefly summarize the state of the art of the project at an advanced stage, highlighting the path of the different Tasks, as well as the main results.

  20. The Orbital Architecture of 55 Cnc: An Orbital Resonance, Jupiter Analog, and Transiting Super-Earth

    NASA Astrophysics Data System (ADS)

    Nelson, Benjamin E.; Payne, M.; Ford, E.; Wright, J.

    2011-09-01

    55 Cnc is the only naked eye star with a known transiting planet (Winn et al. 2011) and one of a few systems with five known planets characterized via Doppler methods. The planets span a wide range of masses and orbital periods. We investigate the orbital architecture, focusing on two of the giant planets near 3:1 mean-motion resonance and the potential impact on the dynamical effects on the other planets. To quantify the uncertainty in the orbital parameters of the 55 Cnc system requires exploring a high-dimensional ( 35) parameter space and using self-consistent N-body integrations, both of which are computationally demanding. To surmount these challenges, we apply a differential evolution Markov chain Monte Carlo algorithm to characterize the orbital properties and masses. We present these results and discuss the implications on the dynamical evolution of the 55 Cnc system.

  1. An iterative learning control method with application for CNC machine tools

    SciTech Connect

    Kim, D.I.; Kim, S.

    1996-01-01

    A proportional, integral, and derivative (PID) type iterative learning controller is proposed for precise tracking control of industrial robots and computer numerical controller (CNC) machine tools performing repetitive tasks. The convergence of the output error by the proposed learning controller is guaranteed under a certain condition even when the system parameters are not known exactly and unknown external disturbances exist. As the proposed learning controller is repeatedly applied to the industrial robot or the CNC machine tool with the path-dependent repetitive task, the distance difference between the desired path and the actual tracked or machined path, which is one of the most significant factors in the evaluation of control performance, is progressively reduced. The experimental results demonstrate that the proposed learning controller can improve machining accuracy when the CNC machine tool performs repetitive machining tasks.

  2. The study of opened CNC system of turning-grinding composite machine tool based on UMAC

    NASA Astrophysics Data System (ADS)

    Wang, Hongjun; Han, Qiushi; Wu, Guoxin; Ma, Chao

    2010-12-01

    The general function analysis of a turning-grinding composite machine tool (TGCM) is done. The structure of the TGCM based on 'process integration with one setup' theory in this paper is presented. The CNC system functions of TGCM are analyzed and the CNC framework of TGCM is discussed. Finally the opened-CNC system for this machine tool is developed based on UMAC (Universal Motion and Automation Controller) included hardware system and software system. The hardware structure layout is put forward and the software system is implemented by using VC++6.0. The hardware system was composed of IPC and UMAC. The general control system meets the requirement of integrity machining and matches the hardware structure system of TGCM. The practical machining experiment results showed that the system is valid with high accuracy and high reliability.

  3. The study of opened CNC system of turning-grinding composite machine tool based on UMAC

    NASA Astrophysics Data System (ADS)

    Wang, Hongjun; Han, Qiushi; Wu, Guoxin; Ma, Chao

    2011-05-01

    The general function analysis of a turning-grinding composite machine tool (TGCM) is done. The structure of the TGCM based on 'process integration with one setup' theory in this paper is presented. The CNC system functions of TGCM are analyzed and the CNC framework of TGCM is discussed. Finally the opened-CNC system for this machine tool is developed based on UMAC (Universal Motion and Automation Controller) included hardware system and software system. The hardware structure layout is put forward and the software system is implemented by using VC++6.0. The hardware system was composed of IPC and UMAC. The general control system meets the requirement of integrity machining and matches the hardware structure system of TGCM. The practical machining experiment results showed that the system is valid with high accuracy and high reliability.

  4. The in-situ 3D measurement system combined with CNC machine tools

    NASA Astrophysics Data System (ADS)

    Zhao, Huijie; Jiang, Hongzhi; Li, Xudong; Sui, Shaochun; Tang, Limin; Liang, Xiaoyue; Diao, Xiaochun; Dai, Jiliang

    2013-06-01

    With the development of manufacturing industry, the in-situ 3D measurement for the machining workpieces in CNC machine tools is regarded as the new trend of efficient measurement. We introduce a 3D measurement system based on the stereovision and phase-shifting method combined with CNC machine tools, which can measure 3D profile of the machining workpieces between the key machining processes. The measurement system utilizes the method of high dynamic range fringe acquisition to solve the problem of saturation induced by specular lights reflected from shiny surfaces such as aluminum alloy workpiece or titanium alloy workpiece. We measured two workpieces of aluminum alloy on the CNC machine tools to demonstrate the effectiveness of the developed measurement system.

  5. 6. DETAIL OF SCROLLED CENTRAL PANEL, FLANKED BY ALLEGORICAL STATUES ...

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

    6. DETAIL OF SCROLLED CENTRAL PANEL, FLANKED BY ALLEGORICAL STATUES (OF LEARNING) AND FESTOONS, ABOVE MAIN ENTRANCE OF THE ROEBLING SCHOOL. - John A. Roebling's Sons Company, Kinkora Works, Village of Roebling, Roebling, Burlington County, NJ

  6. DETAIL OF FENCE FLANKING GATE AT ENTRANCE TO MEMORIAL WALK. ...

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

    DETAIL OF FENCE FLANKING GATE AT ENTRANCE TO MEMORIAL WALK. VIEW TO NORTHEAST. - Rock Island National Cemetery, Rock Island Arsenal, 0.25 mile north of southern tip of Rock Island, Rock Island, Rock Island County, IL

  7. GATE AND FLANKING FENCE AT ENTRANCE TO MEMORIAL WALK. VIEW ...

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

    GATE AND FLANKING FENCE AT ENTRANCE TO MEMORIAL WALK. VIEW TO NORTHEAST. - Rock Island National Cemetery, Rock Island Arsenal, 0.25 mile north of southern tip of Rock Island, Rock Island, Rock Island County, IL

  8. East side detail, showing later wings flanking original entrance on ...

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

    East side detail, showing later wings flanking original entrance on east side. - Fitzsimons General Hospital, Red Cross Building, South Eighth Street Bounded by West McAfee Avenue on South & West Harlow Avenue on North, Aurora, Adams County, CO

  9. View looking northeast of console table and mirror flanked by ...

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

    View looking northeast of console table and mirror flanked by 18th century French chairs in the first floor Reception Hall - Perry Belmont House, 1618 New Hampshire Avenue, NW, Washington, District of Columbia, DC

  10. 1. FRONT (NORTH) SIDE; SMOKESTACKS FLANK PROTECTING BAY THAT CONTAINS ...

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

    1. FRONT (NORTH) SIDE; SMOKESTACKS FLANK PROTECTING BAY THAT CONTAINS COAL ELEVATING EQUIPMENT - Rath Packing Company, Boiler Room, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

  11. A Benchmark Infrared Characterisation of the Super-Earth 55 Cnc e

    NASA Astrophysics Data System (ADS)

    Demory, Brice-Olivier; Kataria, Tiffany; Lewis, Nikole; Krick, Jessica; Queloz, Didier; Gillon, Michael; Stamenkovic, Vlada; Madhusudhan, Nikku; Fortney, Jonathan; de Wit, Julien; Kane, Stephen

    2014-12-01

    The Kepler mission and radial-velocity surveys have revealed that super-Earth exoplanets are not only ubiquitous in our galaxy but also very diverse in terms of physical properties. However, very little is known about their nature because of the paucity of suitable targets amenable to detailed characterization. Two super-Earths, GJ1214b and 55Cnc e, orbit stars that are bright enough to enable detailed atmospheric and interior composition studies, which are crucial to improve our understanding of this class of exoplanets. As of today, 55Cnc e is the only super Earth amenable to occultation and phase curve infrared photometry, as well as a prime target to understand the nature of highly irradiated super Earths. In the past two years, Spitzer observations of 55 Cnc e resulted in photometric lightcurves of unprecedented quality, thanks to the brightness of its host star. We propose an observing program of 180 hours to pursue this effort. Our main goal is to determine whether 55 Cnc e harbors an atmosphere or not. We propose to obtain four orbital phase curves of 55 Cnc e at 4.5 microns and four other at 3.6 microns. Our observations will unambiguously determine whether 55 Cnc e is volatile-poor or volatile-rich. We will also measure for the first time the 3D climate patterns in a super-Earth atmosphere. Finally, our program will deliver precise transit, occultation and phase-curve photometry that will constitute an important legacy regarding the characterization of a super-Earth exoplanet, well in advance of JWST.

  12. CncRNAs: RNAs with both coding and non-coding roles in development.

    PubMed

    Sampath, Karuna; Ephrussi, Anne

    2016-04-15

    RNAs are known to regulate diverse biological processes, either as protein-encoding molecules or as non-coding RNAs. However, a third class that comprises RNAs endowed with both protein coding and non-coding functions has recently emerged. Such bi-functional 'coding and non-coding RNAs' (cncRNAs) have been shown to play important roles in distinct developmental processes in plants and animals. Here, we discuss key examples of cncRNAs and review their roles, regulation and mechanisms of action during development. PMID:27095489

  13. Development of a QFD-based expert system for CNC turning centre selection

    NASA Astrophysics Data System (ADS)

    Prasad, Kanika; Chakraborty, Shankar

    2015-10-01

    Computer numerical control (CNC) machine tools are automated devices capable of generating complicated and intricate product shapes in shorter time. Selection of the best CNC machine tool is a critical, complex and time-consuming task due to availability of a wide range of alternatives and conflicting nature of several evaluation criteria. Although, the past researchers had attempted to select the appropriate machining centres using different knowledge-based systems, mathematical models and multi-criteria decision-making methods, none of those approaches has given due importance to the voice of customers. The aforesaid limitation can be overcome using quality function deployment (QFD) technique, which is a systematic approach for integrating customers' needs and designing the product to meet those needs first time and every time. In this paper, the adopted QFD-based methodology helps in selecting CNC turning centres for a manufacturing organization, providing due importance to the voice of customers to meet their requirements. An expert system based on QFD technique is developed in Visual BASIC 6.0 to automate the CNC turning centre selection procedure for different production plans. Three illustrative examples are demonstrated to explain the real-time applicability of the developed expert system.

  14. CNC Turning Center Operations and Prove Out. Computer Numerical Control Operator/Programmer. 444-334.

    ERIC Educational Resources Information Center

    Skowronski, Steven D.

    This student guide provides materials for a course designed to instruct the student in the recommended procedures used when setting up tooling and verifying part programs for a two-axis computer numerical control (CNC) turning center. The course consists of seven units. Unit 1 discusses course content and reviews and demonstrates set-up procedures…

  15. Learning Control: Sense-Making, CNC Machines, and Changes in Vocational Training for Industrial Work

    ERIC Educational Resources Information Center

    Berner, Boel

    2009-01-01

    The paper explores how novices in school-based vocational training make sense of computerized numerical control (CNC) machines. Based on two ethnographic studies in Swedish schools, one from the early 1980s and one from 2006, it analyses change and continuity in the cognitive, social, and emotional processes of learning how to become a machine…

  16. 78 FR 50135 - CNC Development, Ltd., Exousia Advanced Materials, Inc., and South American Minerals, Inc.; Order...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-16

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE COMMISSION CNC Development, Ltd., Exousia Advanced Materials, Inc., and South American Minerals, Inc.; Order... current and accurate information concerning the securities of South American Minerals, Inc. because it...

  17. Technical and Symbolic Knowledge in CNC Machining: A Study of Technical Workers of Different Backgrounds.

    ERIC Educational Resources Information Center

    Martin, Laura M. W.; Beach, King

    Performances of 45 individuals with varying degrees of formal and informal training in machining and programming were compared on tasks designed to tap intellectual changes that may occur with the introduction of computer numerical control (CNC). Participants--30 machinists, 8 machine operators, and 7 engineers--were asked background questions and…

  18. Basic CNC Operation. Training Workbook [and] Assessment and Training Guide [and] Hands-on Assessment.

    ERIC Educational Resources Information Center

    Anoka-Hennepin Technical Coll., Minneapolis, MN.

    This workbook is intended for students taking a course in basic computer numerical control (CNC) operation that was developed during a project to retrain defense industry workers at risk of job loss or dislocation because of conversion of the defense industry. The workbook contains daily training guides for each of the course's 13 sessions. Among…

  19. The Implications of Flank Vents on Olympus Mons

    NASA Astrophysics Data System (ADS)

    Peters, S.; Christensen, P. R.

    2014-12-01

    Flank vents are a common feature on polygenetic volcanoes. They indicate that magma has propagated away from the main conduit and/or magma chamber. Flank vents and flank eruptions have been documented and studied on a number of terrestrial volcanoes and to a lesser degree on Mars. The distribution of volcanic vents about a central caldera can provide information on radial dikes and tectonic stresses acting on the volcano, and can constrain models involving the emplacement and flexure of the edifice (e.g. Nakamura, 1976; McGovern and Solomon, 1993). In the absence of spectral data (due to optically thick dust cover) and in situ observations, morphology is a powerful tool for ascertaining the eruptive and tectonic history of Olympus Mons. Approximately 190 high-resolution CTX (Context Camera) images covering Olympus Mons have been mosaicked together. The analysis of a CTX mosaic reveals Mars's largest shield volcano in stunning detail and allows for a thorough analysis of the targeted features. Preliminary results show numerous flank vents some of which produce leveed channels on the slopes of Olympus Mons. Some vents display varying morphologies, suggesting that the style of volcanism has evolved over time. Flank vents are observed to occur over a range of elevations, although a paucity of vents is observed on the lower flank. Analyses are ongoing and include mapping the spatial and elevation distribution of flank vents on the shield. Once mapped, the distribution of flank vents will define the orientation of tectonic stresses acting on Olympus Mons and help determine whether they are influenced by underlying topography, regional scale processes or a combination of both. In addition, these vents act as a window into the subsurface which can help characterize dike emplacement within the shield. Furthermore, the morphology of flank vents will provide information on the evolution of their eruptive styles. All of this information is crucial to help understand the

  20. Chemical crosslinking of acrylic acid to form biocompatible pH sensitive hydrogel reinforced with cellulose nanocrystals (CNC)

    SciTech Connect

    Lim, Lim Sze; Ahmad, Ishak; Lazim, Mohd Azwani Shah Mat; Amin, Mohd. Cairul Iqbal Mohd

    2014-09-03

    The purpose of this study is to produce a novel pH and temperature sensitive hydrogel, composed of poly(acrylic acid) (PAA) and cellulose nanocrystal (CNC). CNC was extracted from kenaf fiber through a series of alkali and bleaching treatments followed by acid hydrolysis. The PAA was then subjected to chemical cross-linking using the cross-linking agent (N,N-methylenebisacrylamide) with CNC entrapped in PAA matrix. The mixture was casted onto petri dish to obtain disc shape hydrogel. The effects of reaction conditions such as the ratio of PAA and CNC on the swelling behavior of the hydrogel obtained towards pH and temperature were studied. The obtained hydrogel was further subjected to different tests such swelling test for swelling behaviour at different pH and temperature along with scanning electron microscopy (SEM) for morphology analysis. The hydrogel obtained showed excellent pH sensitivity and obtained maximum swelling at pH 7. Besides that, hydrogel obtained showed significant increase in swelling ratio when temperature of swelling medium was increased from 25°C to 37°C. SEM micrograph showed that the pore size of the hydrogel decreases with increase of CNC content proving that the hydrogel structure became more rigid with addition of CNC. The PAA/CNC hydrogel with such excellent sensitivity towards pH and temperature can be developed further as drug carrier.

  1. In-situ polymerized cellulose nanocrystals (CNC)-poly(l-lactide) (PLLA) nanomaterials and applications in nanocomposite processing.

    PubMed

    Miao, Chuanwei; Hamad, Wadood Y

    2016-11-20

    CNC-PLLA nanomaterials were synthesized via in-situ ring-opening polymerization of l-lactide in the presence of CNC, resulting in hydrophobic, homogeneous mixture of PLLA-grafted-CNC and free PLLA homopolymer. The free PLLA serves two useful functions: as barrier to further prevent PLLA-g-CNC from forming aggregates, and in creating improved interfacial properties when these nanomaterials are blended with other polymers, hence enhancing their performance. CNC-PLLA nanomaterials can be used for medical or engineering applications as-they-are or by compounding with suitable biopolymers using versatile techniques, such as solution casting, co-extrusion or injection molding, to form hybrid nanocomposites of tunable mechanical properties. When compounded with commercial-grade PLA, the resulting CNC-PLA nanocomposites appear transparent and have tailored (dynamic and static) mechanical and barrier properties, approaching those of poly(ethylene terephthalate), PET. The effect of reaction conditions on the properties of CNC-PLLA nanomaterials have been carefully studied and detailed throughout the paper. PMID:27561528

  2. Chemical crosslinking of acrylic acid to form biocompatible pH sensitive hydrogel reinforced with cellulose nanocrystals (CNC)

    NASA Astrophysics Data System (ADS)

    Lim, Lim Sze; Ahmad, Ishak; Lazim, Mohd Azwani Shah Mat; Amin, Mohd. Cairul Iqbal Mohd

    2014-09-01

    The purpose of this study is to produce a novel pH and temperature sensitive hydrogel, composed of poly(acrylic acid) (PAA) and cellulose nanocrystal (CNC). CNC was extracted from kenaf fiber through a series of alkali and bleaching treatments followed by acid hydrolysis. The PAA was then subjected to chemical cross-linking using the cross-linking agent (N,N-methylenebisacrylamide) with CNC entrapped in PAA matrix. The mixture was casted onto petri dish to obtain disc shape hydrogel. The effects of reaction conditions such as the ratio of PAA and CNC on the swelling behavior of the hydrogel obtained towards pH and temperature were studied. The obtained hydrogel was further subjected to different tests such swelling test for swelling behaviour at different pH and temperature along with scanning electron microscopy (SEM) for morphology analysis. The hydrogel obtained showed excellent pH sensitivity and obtained maximum swelling at pH 7. Besides that, hydrogel obtained showed significant increase in swelling ratio when temperature of swelling medium was increased from 25°C to 37°C. SEM micrograph showed that the pore size of the hydrogel decreases with increase of CNC content proving that the hydrogel structure became more rigid with addition of CNC. The PAA/CNC hydrogel with such excellent sensitivity towards pH and temperature can be developed further as drug carrier.

  3. CCD Photometric Study of the Contact Binary TX Cnc in the Young Open Cluster NGC 2632

    NASA Astrophysics Data System (ADS)

    Liu, Liang; Qian, Sheng-Bang; Boonrucksar, Soonthornthum; Zhu, Li-Ying; He, Jia-Jia; Yuan, J.-Z.

    2007-06-01

    TX Cnc is a member of the young open cluster NGC2632. In the present paper, four CCD epochs of light minimum and a complete V light curve of TX Cnc are presented. A period investigation based on all available photoelectric or CCD data showed that it is superimposed on a long-term increase (dP/dt=+3.97×10-8) and weak evidence suggests that it includes a small-amplitude period oscillation (A3=0d.0028; T3=26.6yr). The light curves in the V band obtained in 2004 were analyzed with the 2003 version of the W-D code. It was shown that TX Cnc is an overcontact binary system with a degree of contact factor f=24.8%. The absolute parameters of the system were calculated: M1=1.319±0.007M⊙, M2=0.600±0.01M⊙; R1=1.28±0.19R⊙, R2=0.91±0.13R⊙. TX Cnc may be on the TRO-controlled stage of the evolutionary scheme proposed by Qian (2001a, b, 2003a), and may contain an invisible tertiary component (m3≈0.097M⊙). If this is true, the tertiary component has played an important role in the formation and evolution of TX Cnc by removing angular momentum from the central system (Pribulla & Rucinski 2006). In this way the contact binary configuration can be formed in the shortlife time of a young open cluster via AML.

  4. My patient has abdominal and flank pain: Identifying renal causes.

    PubMed

    Cox, Christopher; MacDonald, Scott; Henneberry, Ryan; Atkinson, Paul R

    2015-11-01

    Acute flank and abdominal pain are common presenting complaints in the emergency department. With increasing access to point-of-care ultrasound (PoCUS), emergency physicians have an added tool to help identify renal problems as a cause of a patient's pain. PoCUS for hydronephrosis has a sensitivity of 72-83.3% and a varying specificity, similar to radiology-performed ultrasonography. In addition to assessment for hydronephrosis, PoCUS can help emergency physicians to exclude other serious causes of flank and abdominal pain such as the presence of an abdominal aortic aneurysm, or free fluid in the intraperitoneal space, which could represent hemorrhage. Use of PoCUS for the assessment of flank pain has resulted in more rapid diagnosis, decreased use of computed tomography, and shorter emergency department length of stay. PMID:27433264

  5. West Flank Coso FORGE Magnetotelluric 3D Data

    SciTech Connect

    Doug Blankenship

    2016-01-01

    This is the 3D version of the MT data for the West Flank FORGE area.The Coso geothermal field has had three Magnetotelluric (MT) datasets collected including surveys in 2003, 2006, and 2011. The final collection, in 2011, expanded the survey to the west and covers the West Flank of FORGE area.This most recent data set was collected by Schlumberger/WesternGeco and inverted by the WesternGeco GeoSolutions Integrated EM Center of Excellence in Milan, Italy; the 2003 and 2006 data were integrated for these inversions in the present study.

  6. Transducer model produces facilitation from opposite-sign flanks

    NASA Technical Reports Server (NTRS)

    Solomon, J. A.; Watson, A. B.; Morgan, M. J.

    1999-01-01

    Small spots, lines and Gabor patterns can be easier to detect when they are superimposed upon similar spots, lines and Gabor patterns. Traditionally, such facilitation has been understood to be a consequence of nonlinear contrast transduction. Facilitation has also been reported to arise from non-overlapping patterns with opposite sign. We point out that this result does not preclude the traditional explanation for superimposed targets. Moreover, we find that facilitation from opposite-sign flanks is weaker than facilitation from same-sign flanks. Simulations with a transducer model produce opposite-sign facilitation.

  7. 10. INTERIOR OF LIVING ROOM SHOWING FRONT DOOR FLANKED BY ...

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

    10. INTERIOR OF LIVING ROOM SHOWING FRONT DOOR FLANKED BY SLIDING GLASS WINDOWS AND ELECTRICAL WALL HEATER. ORIGINAL 1-LIGHT OVER 1-LIGHT, DOUBLE-HUNG WINDOW AT PHOTO RIGHT. CEILING VENT TO CHIMNEY AT RIGHT UPPER PHOTO CENTER. VIEW TO SOUTHEAST. - Bishop Creek Hydroelectric System, Plant 4, Worker Cottage, Bishop Creek, Bishop, Inyo County, CA

  8. FACILITY 713, LIVING ROOM SHOWING DIAMONDPANED WINDOWS FLANKING THE FIREPLACE, ...

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

    FACILITY 713, LIVING ROOM SHOWING DIAMOND-PANED WINDOWS FLANKING THE FIREPLACE, AND LEADED-GLASS WINDOWS IN DINING ROOM IN RIGHT BACKGROUND, VIEW FACING SOUTHEAST. - Schofield Barracks Military Reservation, Central-Entry Single-Family Housing Type, Between Bragg & Grime Streets near Ayres Avenue, Wahiawa, Honolulu County, HI

  9. An efficient method for flanking sequence isolation in barley

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An adapter ligation method was developed to determine native barley (Hordeum vulgare) sequences flanking Ds insertions and barley ESTs. This method is simple and efficient, with the majority of queries returning valid sequence information. This report describes the protocol in detail, quantifies its...

  10. West Flank Coso, CA FORGE Natural Fracture data

    DOE Data Explorer

    Doug Blankenship

    2016-05-16

    Natural fracture data from wells 33-7, 33A-7,52A-7, 52B-7 and 83-11 at West Flank. Fracture orientations were determined from image logs of these wells (see accompanying submissions). Data files contain depth, apparent (in wellbore reference frame) and true (in geographic reference frame) azimuth and dip, respectively.

  11. Nature of thrusting along western flank of Bighorn Mountains, Wyoming

    SciTech Connect

    Noggle, K.S.

    1986-08-01

    The northern portion of the Bighorn Mountains is characterized by opposed mountain-front thrusts, of which the southwest direction is dominant. Blind basement thrusts along the northeastern flank do not pierce the folded Paleozoic cover; whereas on the western flank, southwest-directed thrust segments expose Precambrian rocks along a 24-km (14-mi) extent. Field studies on the western flank show evidence of four major southwest-directed thrust segments delineated by tear-fault boundaries, which include from northwest to southeast: (1) the Five Springs thrust, a low-angle, out-of-the-syncline fault mainly involving the sedimentary sequence; (2) the Bear Creek thrust, a continuation of the Five Springs out-of-the-syncline fault; (3) the South Beaver Creek thrust, which juxtaposes Precambrian rocks against a tectonically thinned, overturned anticlinal limb of Mississippian through Jurassic rocks and which is inward from an out-of-the-syncline thrust involving little displacement of Jurassic formations; and (4) a mountain-front reentrant that coincides with the zone where the South Beaver Creek thrust continues beneath Paleozoic cover, causing the upper flexure of a double monocline. The central portion of the Bighorn Mountains is thrust eastward, whereas the northern portion is thrust southwestward with much less displacement. The segmented association of southwest-directed basement thrusts along the western flank of the northern Bighorns is indicative of the major transport direction for that portion of the Bighorn uplift.

  12. Erosion of the submarine flanks of the Canary Islands

    NASA Astrophysics Data System (ADS)

    Mitchell, Neil C.; Dade, W. Brian; Masson, Douglas G.

    2003-12-01

    Surveying with multibeam echo sounders around old (≫1 Ma) volcanic ocean islands reveals that their submarine flanks contain a strong downslope-oriented ridge-and-valley corrugation, which modifies the original volcanic morphology of lava terraces and cones. By analogy with canyons in other settings, this corrugation was probably caused by channel incision by erosive sedimentary mass flows such as turbidity currents and debris flows. We adapt a method first used in subaerial geomorphology to isolate the erosion depth (exhumation) and apply it to the eroded flanks of the 6-8 Ma Anaga massif of Tenerife. The channels formed around this massif divert around local topographic highs. These highs, which are probably original volcanic cones, are therefore preferentially preserved during erosion, so that their elevations can be used to construct an artificial reference surface. Terrain depth was calculated by subtracting this reference surface from measured bathymetry. Comparison of the terrain depth of the old, eroded submarine flank of Anaga with that of the young, mostly unaltered submarine flank of El Hierro allows us to infer the mean depth of Anaga's submarine erosion, which is ˜100 m. Volcanic terrains can be dated by radiometric methods, so they also provide a way of quantifying long-term denudation rates. We infer that submarine denudation of Anaga has occurred at comparable rates to that of subaerial lowlands and much slower than denudation of highlands, illustrated locally by the more extensive erosion of the subaerial Anaga edifice.

  13. Urolithiasis presenting as right flank pain: a case report

    PubMed Central

    Chung, Chadwick; Stern, Paula J.; Dufton, John

    2013-01-01

    Background: Urolithiasis refers to renal or ureteral calculi referred to in lay terminology as a kidney stone. Utolithiasis is a potential emergency often resulting in acute abdominal, low back, flank or groin pain. Chiropractors may encounter patients when they are in acute pain or after they have recovered from the acute phase and should be knowledgeable about the signs, symptoms, potential complications and appropriate recommendations for management. Case presentation: A 52 year old male with acute right flank pain presented to the emergency department. A ureteric calculus with associated hydronephrosis was identified and he was prescribed pain medications and discharged to pass the stone naturally. One day later, he returned to the emergency department with severe pain and was referred to urology. He was managed with a temporary ureteric stent and antibiotics. Conclusion: This case describes a patient with acute right flank and lower quadrant pain which was diagnosed as an obstructing ureteric calculus. Acute management and preventive strategies in patients with visceral pathology such as renal calculi must be considered in patients with severe back and flank pain as it can progress to hydronephrosis and kidney failure. PMID:23483000

  14. PLLA-grafted cellulose nanocrystals: Role of the CNC content and grafting on the PLA bionanocomposite film properties.

    PubMed

    Lizundia, Erlantz; Fortunati, Elena; Dominici, Franco; Vilas, José Luis; León, Luis Manuel; Armentano, Ilaria; Torre, Luigi; Kenny, Josè M

    2016-05-20

    Cellulose nanocrystals (CNC), extracted from microcrystalline cellulose by acid hydrolysis, were grafted by ring opening polymerization of L-Lactide initiated from the hydroxyl groups available at their surface and two different CNC:L-lactide ratios (20:80 and 5:95) were obtained. The resulting CNC-g-PLLA nanohybrids were incorporated in poly(lactic acid) (PLA) matrix by an optimized extrusion process at two different content (1 wt.% and 3 wt.%) and obtained bionanocomposite films were characterized by thermal, mechanical, optical and morphological properties. Thermal analysis showed CNC grafted with the higher ratio of lactide play a significant role as a nucleating agent. Moreover, they contribute to a significant increase in the crystallization rate of PLA, and the best efficiency was revealed with 3 wt.% of CNC-g-PLLA. This effect was confirmed by the increased in Young's modulus, suggesting the CNC graft ratio and content contribute significantly to the good dispersion in the matrix, positively affecting the final bionanocomposite properties. PMID:26917380

  15. Vision-based on-machine measurement for CNC machine tool

    NASA Astrophysics Data System (ADS)

    Xia, Ruixue; Han, Jiang; Lu, Rongsheng; Xia, Lian

    2015-02-01

    A vision-based on-machine measurement system (OMM) was developed to improve manufacturing effectiveness. It was based on a visual probe to enable the CNC machine tool itself to act as a coordinate measuring machine (CMM) to inspect a workpiece. The proposed OMM system was composed of a visual probe and two software modules: computer-aided inspection planning (CAIP) module and measurement data processing (MDP) module. The auto-focus function of the visual probe was realized by using astigmatic method. The CAIP module was developed based on a CAD development platform with Open CASCADE as its kernel. The MDP module includes some algorithms for determination of inspection parameters, for example, the chamfered hole was measured through focus variation. The entire system was consequently verified on a CNC milling machine.

  16. Facile synthesis of CNC-MnO2 hybrid as a supercapacitor electrode

    NASA Astrophysics Data System (ADS)

    Su, Deqiao; Pan, Lujun; Fu, Xin; Ma, He

    2015-01-01

    A facile and efficient hydrothermal approach has been developed to synthesize three dimensional hybrid of manganese dioxide (MnO2) and carbon nanocoils (CNCs) as a kind of electrode materials for supercapacitors. This hybrid is prepared by anchoring uniformly porous MnO2 nanowiskers over the surface of CNCs. The electrochemical properties of CNC-MnO2 electrode have been measured by a three electrode configuration, which exhibits high specific capacitance with values up to 387 F/g at a scan rate of 10 mV/s and good cycling stability. These results suggest that the CNC-MnO2 hybrid is comparable or superior to other carbon-based materials coated with MnO2 nanowiskers.

  17. Comparison between predicted and actual accuracies for an Ultra-Precision CNC measuring machine

    SciTech Connect

    Thompson, D.C.; Fix, B.L.

    1995-05-30

    At the 1989 CIRP annual meeting, we reported on the design of a specialized, ultra-precision CNC measuring machine, and on the error budget that was developed to guide the design process. In our paper we proposed a combinatorial rule for merging estimated and/or calculated values for all known sources of error, to yield a single overall predicted accuracy for the machine. In this paper we compare our original predictions with measured performance of the completed instrument.

  18. Thread milling on N/C and CNC milling machines. Final report

    SciTech Connect

    Ashbaugh, F.A.; Murry, K.R.

    1985-12-01

    A unique thread-cutting tool design has been developed which permits threading of internal or external features; right- or left-hand threads; and standard, metric, or special pitches within a given size range without changing tools. One of the major advantages of the technique is the ability to produce small threads on N/C and CNC milling manchines. This study presents results showing fabrication of quality threads as small as number 0-80 in selected materials.

  19. Acoustic and Elastodynamic Redatuming for VSP Salt Dome Flank Imaging

    NASA Astrophysics Data System (ADS)

    Lu, R.; Willis, M.; Toksoz, N.

    2007-12-01

    We apply an extension of the concept of Time Reversed Acoustics (TRA) for imaging salt dome flanks using Vertical Seismic Profile (VSP) data. We demonstrate its performance and capabilities on both synthetic acoustic and elastic seismic data from a Gulf of Mexico (GOM) model. This target-oriented strategy eliminates the need for the traditional complex process of velocity estimation, model building, and iterative depth migration to remove the effects of the salt canopy and surrounding overburden. In this study, we use data from surface shots recorded in a well from a walkaway VSP survey. The method, called redatuming, creates a geometry as if the source and receiver pairs had been located in the borehole at the positions of the receivers. This process generates effective downhole shot gathers without any knowledge of the overburden velocity structure. The resulting shot gathers are less complex since the VSP ray paths from the surface source are shortened and moved to be as if they started in the borehole, then reflected off the salt flank region and captured in the borehole. After redatuming, we apply multiple passes of prestack migration from the reference datum of the borehole. In our example, the first pass migration, using only simple vertical velocity gradient model, reveals the outline of the salt edge. A second pass of reverse-time prestack depth migration using the full, two-way wave equation, is performed with an updated velocity model that now consists of the velocity gradient and the salt dome. The second pass migration brings out the dipping sediments abutting the salt flank because these reflectors were illuminated by energy that bounced off the salt flank forming prismatic reflections.

  20. Flexural analysis of uplifted rift flanks on Venus

    NASA Technical Reports Server (NTRS)

    Evans, Susan A.; Simons, Mark; Solomon, Sean C.

    1992-01-01

    Knowledge of the thermal structure of a planet is vital to a thorough understanding of its general scheme of tectonics. Since no direct measurements of heat flow or thermal gradient are available for Venus, most estimates have been derived from theoretical considerations or by analog with the Earth. The flexural response of the lithosphere to applied loads is sensitive to regional thermal structure. Under the assumption that the yield strength as a function of depth can be specified, the temperature gradient can be inferred from the effective elastic plate thickness. Previous estimates of the effective elastic plate thickness of Venus range from 11-18 km for the foredeep north of Uorsar Rupes to 30-60 km for the annular troughs around several coronae. Thermal gradients inferred for these regions are 14-23 K km(exp -1) and 4-9 K km(exp -1) respectively. In this study, we apply the same techniques to investigate the uplifted flanks of an extensional rift. Hypotheses for the origin of uplifted rift flanks on Earth include lateral transport of heat from the center of the rift, vertical transport of heat by small-scale convection, differential thinning of the lithosphere, dynamical uplift, and isostatic response to mechanical uploading of the lithosphere. The 1st hypothesis is considered the dominant contributor to terrestrial rift flanks lacking evidence for volcanic activity, particularly for rift structures that are no longer active. In this study, we model the uplifted flanks of a venusian rift as the flexural response to a vertical end load.

  1. The hamster flank organ model: Is it relevant to man

    SciTech Connect

    Franz, T.J.; Lehman, P.A.; Pochi, P.; Odland, G.F.; Olerud, J. )

    1989-10-01

    The critical role that androgens play in the etiology of acne has led to a search for topically active antiandrogens and the frequent use of the flank organ of the golden Syrian hamster as an animal model. 17-alpha-propyltestosterone (17-PT) has been identified as having potent antiandrogenic activity in the hamster model, and this report describes its clinical evaluation. Two double-blind placebo controlled studies comparing 4% 17-PT in 80% alcohol versus vehicle alone were conducted. One study examined 17-PT sebosuppressive activity in 20 subjects. The second study examined its efficacy in 44 subjects having mild to moderate acne. A third study measured in vitro percutaneous absorption of 17-PT through hamster flank and monkey skin, and human face skin in-vivo, using radioactive drug. 17-PT was found to be ineffective in reducing either the sebum excretion rate or the number of inflammatory acne lesions. Failure of 17-PT to show clinical activity was not a result of poor percutaneous absorption. Total absorption in man was 7.7% of the dose and only 1.0% in the hamster. The sebaceous gland of hamster flank organ is apparently more sensitive to antiandrogens than the human sebaceous gland.

  2. Renal infarction: an uncommon mimic presenting with flank pain.

    PubMed

    Manfredini, R; La Cecilia, O; Ughi, G; Kuwornu, H; Bressan, S; Regoli, F; Orzincolo, C; Daniele, C; Gallerani, M

    2000-05-01

    A 39-year-old woman arrived to the emergency department complaining of a constant, progressive, left flank pain, with no beneficial effect from spasmolytic and nonsteroidal antiinflammatory drugs. Two years before, she suffered another episode of right flank pain and stranguria, but instrumental examinations (ultrasonography, urography) remained negative. Besides a mild tenderness in the left flank, physical examination was normal. Blood chemistry panel showed leukocytosis (17.2 x 10(3) mL, neutrophils 82.8%) and a slight increase of serum lactate dehydrogenase (LDH) (543 U/L versus 230 to 460 U/L). Urinanalysis showed a slight hemoglobinuria (0.5 mg/dL), and sediment contained some red cells and leukocytes. Diagnostic examinations (ultrasonography, computed tomography) showed a left renal nonhomogeneous space-occupying lesion, orientative for renal malignancy. She was transferred to the urology department and operated. Both intraoperatory and histological diagnosis was ischemic infarction and, after exclusion of all possible underlying causes, final diagnosis was idiopathic renal infarction. Diagnostic procedures and literature reports are discussed. PMID:10830691

  3. West Flank Coso, CA FORGE 3D geologic model

    DOE Data Explorer

    Doug Blankenship

    2016-03-01

    This is an x,y,z file of the West Flank FORGE 3D geologic model. Model created in Earthvision by Dynamic Graphic Inc. The model was constructed with a grid spacing of 100 m. Geologic surfaces were extrapolated from the input data using a minimum tension gridding algorithm. The data file is tabular data in a text file, with lithology data associated with X,Y,Z grid points. All the relevant information is in the file header (the spatial reference, the projection etc.) In addition all the fields in the data file are identified in the header.

  4. Design and accuracy analysis of a metamorphic CNC flame cutting machine for ship manufacturing

    NASA Astrophysics Data System (ADS)

    Hu, Shenghai; Zhang, Manhui; Zhang, Baoping; Chen, Xi; Yu, Wei

    2016-05-01

    The current research of processing large size fabrication holes on complex spatial curved surface mainly focuses on the CNC flame cutting machines design for ship hull of ship manufacturing. However, the existing machines cannot meet the continuous cutting requirements with variable pass conditions through their fixed configuration, and cannot realize high-precision processing as the accuracy theory is not studied adequately. This paper deals with structure design and accuracy prediction technology of novel machine tools for solving the problem of continuous and high-precision cutting. The needed variable trajectory and variable pose kinematic characteristics of non-contact cutting tool are figured out and a metamorphic CNC flame cutting machine designed through metamorphic principle is presented. To analyze kinematic accuracy of the machine, models of joint clearances, manufacturing tolerances and errors in the input variables and error models considering the combined effects are derived based on screw theory after establishing ideal kinematic models. Numerical simulations, processing experiment and trajectory tracking experiment are conducted relative to an eccentric hole with bevels on cylindrical surface respectively. The results of cutting pass contour and kinematic error interval which the position error is from-0.975 mm to +0.628 mm and orientation error is from-0.01 rad to +0.01 rad indicate that the developed machine can complete cutting process continuously and effectively, and the established kinematic error models are effective although the interval is within a `large' range. It also shows the matching property between metamorphic principle and variable working tasks, and the mapping correlation between original designing parameters and kinematic errors of machines. This research develops a metamorphic CNC flame cutting machine and establishes kinematic error models for accuracy analysis of machine tools.

  5. Finger milling-cutter CNC generating hypoid pinion tooth surfaces based on modified-roll method and machining simulation

    NASA Astrophysics Data System (ADS)

    Li, Genggeng; Deng, Xiaozhong; Wei, Bingyang; Lei, Baozhen

    2011-05-01

    The two coordinate systems of cradle-type hypoid generator and free-form CNC machine tool by application disc milling-cutter to generate hypoid pinion tooth surfaces based on the modified-roll method were set up, respectively, and transformation principle and method for machine-tool settings between the two coordinate systems was studied. It was presented that finger milling-cutter was mounted on imagined disc milling-cutter and its motion was controlled directly by CNC shafts to replace disc milling-cutter blades effective cutting motion. Finger milling-cutter generation accomplished by ordered circular interpolation was determined, and interpolation center, starting and ending were worked out. Finally, a hypoid pinion was virtually machined by using CNC machining simulation software VERICUT.

  6. Finger milling-cutter CNC generating hypoid pinion tooth surfaces based on modified-roll method and machining simulation

    NASA Astrophysics Data System (ADS)

    Li, Genggeng; Deng, Xiaozhong; Wei, Bingyang; Lei, Baozhen

    2010-12-01

    The two coordinate systems of cradle-type hypoid generator and free-form CNC machine tool by application disc milling-cutter to generate hypoid pinion tooth surfaces based on the modified-roll method were set up, respectively, and transformation principle and method for machine-tool settings between the two coordinate systems was studied. It was presented that finger milling-cutter was mounted on imagined disc milling-cutter and its motion was controlled directly by CNC shafts to replace disc milling-cutter blades effective cutting motion. Finger milling-cutter generation accomplished by ordered circular interpolation was determined, and interpolation center, starting and ending were worked out. Finally, a hypoid pinion was virtually machined by using CNC machining simulation software VERICUT.

  7. Infrared photometry of the RS CVn short-period systems - XY UMa and WY Cnc

    SciTech Connect

    Arevalo, M.J.; Lazaro, C. )

    1990-03-01

    Infrared J and K light curves of two RS CVn short-period systems, XY UMa and WY Cnc, are presented. Both systems show similar variability in the infrared to that observed in the visual. From the colors an infrared excess is inferred for the primary component of both systems. A new determination of their geometrical elements is presented and the resulting parameters are compared to those previously obtained from visible photometry. The light curves show peculiarities that may indicate the presence of gas streams in the systems. 27 refs.

  8. The effect of the model posture on the forming quality in the CNC incremental forming

    NASA Astrophysics Data System (ADS)

    Zhu, H.; Zhang, W.; Bai, J. L.; Yu, C.; Xing, Y. F.

    2015-12-01

    Sheet rupture caused by a sheet metal thickness non-uniformity persists in CNC (Computer Numerical Control) incremental forming. Because the forming half cone angle is determined by the orientation of the model to be formed, so is the sheet metal's uniformity. The finite element analysis models for the two kinds of the postures of the model were established, and the digital simulation was conducted by using the ANSYS/LA-DYNA software. The effect of the model's posture on the sheet thickness distribution and the sheet thickness thinning rate were studied by comparing the simulation results of two kinds of the finite elements analyzes.

  9. Plasma Transport at the Magnetospheric Flank Boundary. Final report

    SciTech Connect

    Otto, Antonius

    2012-04-23

    Progress is highlighted in these areas: 1. Model of magnetic reconnection induced by three-dimensional Kelvin Helmholtz (KH) modes at the magnetospheric flank boundary; 2. Quantitative evaluation of mass transport from the magnetosheath onto closed geomagnetic field for northward IMF; 3. Comparison of mass transfer by cusp reconnection and Flank Kelvin Helmholtz modes; 4. Entropy constraint and plasma transport in the magnetotail - a new mechanism for current sheet thinning; 5. Test particle model for mass transport onto closed geomagnetic field for northward IMF; 6. Influence of density asymmetry and magnetic shear on (a) the linear and nonlinear growth of 3D Kelvin Helmholtz (KH) modes, and (b) three-dimensional KH mediated mass transport; 7. Examination of entropy and plasma transport in the magnetotail; 8. Entropy change and plasma transport by KH mediated reconnection - mixing and heating of plasma; 9. Entropy and plasma transport in the magnetotail - tail reconnection; and, 10. Wave coupling at the magnetospheric boundary and generation of kinetic Alfven waves.

  10. Characterization of the Nanog 5'-flanking Region in Bovine.

    PubMed

    Choi, Don-Ho; Kim, Duk-Jung; Song, Ki-Duk; Park, Hwan-Hee; Ko, Tae Hyun; Pyao, Yuliya; Chung, Ku-Min; Cha, Seok Ho; Sin, Young-Su; Kim, Nam-Hyung; Lee, Woon-Kyu

    2016-10-01

    Bovine embryonic stem cells have potential for use in research, such as transgenic cattle generation and the study of developmental gene regulation. The Nanog may play a critical role in maintenance of the undifferentiated state of embryonic stem cells in the bovine, as in murine and human. Nevertheless, efforts to study the bovine Nanog for pluripotency-maintaining factors have been insufficient. In this study, in order to understand the mechanisms of transcriptional regulation of the bovine Nanog, the 5'-flanking region of the Nanog was isolated from ear cells of Hanwoo. Results of transient transfection using a luciferase reporter gene under the control of serially deleted 5'-flanking sequences revealed that the -134 to -19 region contained the positive regulatory sequences for the transcription of the bovine Nanog. Results from mutagenesis studies demonstrated that the Sp1-binding site that is located in the proximal promoter region plays an important role in transcriptional activity of the bovine Nanog promoter. The electrophoretic mobility shift assay with the Sp1 specific antibody confirmed the specific binding of Sp1 transcription factor to this site. In addition, significant inhibition of Nanog promoter activity by the Sp1 mutant was observed in murine embryonic stem cells. Furthermore, chromatin-immunoprecipitation assay with the Sp1 specific antibody confirmed the specific binding of Sp1 transcription factor to this site. These results suggest that Sp1 is an essential regulatory factor for bovine Nanog transcriptional activity. PMID:27165025

  11. Comparative Evaluation of Midventral and Flank Laparotomy Approaches in Goat

    PubMed Central

    Abubakar, A. A.; Andeshi, R. A.; Yakubu, A. S.; Lawal, F. M.; Adamu, U.

    2014-01-01

    The aim of the study was to compare two laparotomy approaches (flank and midventral). Ten (n = 10) apparently healthy goats of different breeds and sex, average age of 12 ± 2.1 months, and average weight of 13.4 ± 2 kg were used for the investigation. The goats were randomly divided into flank and midventral groups, each group comprising five goats (n = 5). Standard aseptic laparotomy was performed under lumbosacral epidural anaesthesia with mild sedation. Postsurgical wound score showed significant difference (P < 0.05) in erythema at 18–24 hours and 10–14 days after surgery between the two approaches; significant difference of dehiscence between the two groups was also recorded at 10–14 days after surgery. Total white blood cells (WBC) and lymphocytes counts were significantly different (P < 0.05) at the first and second week after surgery. There was significant difference of platelets critical value and platelets dimension width at the first and second week after surgery. Significant difference of packed cells volume between the two approaches was also recorded one week after surgery. It was concluded that midventral laparotomy approach can be conveniently and safely performed under aseptic precautions without fear of intra- and postoperative clinical problems. PMID:26464943

  12. Comparative Evaluation of Midventral and Flank Laparotomy Approaches in Goat.

    PubMed

    Abubakar, A A; Andeshi, R A; Yakubu, A S; Lawal, F M; Adamu, U

    2014-01-01

    The aim of the study was to compare two laparotomy approaches (flank and midventral). Ten (n = 10) apparently healthy goats of different breeds and sex, average age of 12 ± 2.1 months, and average weight of 13.4 ± 2 kg were used for the investigation. The goats were randomly divided into flank and midventral groups, each group comprising five goats (n = 5). Standard aseptic laparotomy was performed under lumbosacral epidural anaesthesia with mild sedation. Postsurgical wound score showed significant difference (P < 0.05) in erythema at 18-24 hours and 10-14 days after surgery between the two approaches; significant difference of dehiscence between the two groups was also recorded at 10-14 days after surgery. Total white blood cells (WBC) and lymphocytes counts were significantly different (P < 0.05) at the first and second week after surgery. There was significant difference of platelets critical value and platelets dimension width at the first and second week after surgery. Significant difference of packed cells volume between the two approaches was also recorded one week after surgery. It was concluded that midventral laparotomy approach can be conveniently and safely performed under aseptic precautions without fear of intra- and postoperative clinical problems. PMID:26464943

  13. Ground-based Transit Observations of the Super-Earth 55 Cnc e

    NASA Astrophysics Data System (ADS)

    de Mooij, E. J. W.; López-Morales, M.; Karjalainen, R.; Hrudkova, M.; Jayawardhana, Ray

    2014-12-01

    We report the first ground-based detections of the shallow transit of the super-Earth exoplanet 55 Cnc e using a 2 m class telescope. Using differential spectrophotometry, we observed one transit in 2013 and another in 2014, with average spectral resolutions of ~700 and ~250, spanning the Johnson BVR photometric bands. We find a white light planet-to-star radius ratio of 0.0190-0.0027+0.0023 from the 2013 observations and 0.0200-0.0018+0.0017 from the 2014 observations. The two data sets combined result in a radius ratio of 0.0198-0.0014+0.0013. These values are all in agreement with previous space-based results. Scintillation noise in the data prevents us from placing strong constraints on the presence of an extended hydrogen-rich atmosphere. Nevertheless, our detections of 55 Cnc e in transit demonstrate that moderate-sized telescopes on the ground will be capable of routine follow-up observations of super-Earth candidates discovered by the Transiting Exoplanet Survey Satellite around bright stars. We expect it also will be possible to place constraints on the atmospheric characteristics of those planets by devising observational strategies to minimize scintillation noise.

  14. cncRNAs: Bi-functional RNAs with protein coding and non-coding functions

    PubMed Central

    Kumari, Pooja; Sampath, Karuna

    2015-01-01

    For many decades, the major function of mRNA was thought to be to provide protein-coding information embedded in the genome. The advent of high-throughput sequencing has led to the discovery of pervasive transcription of eukaryotic genomes and opened the world of RNA-mediated gene regulation. Many regulatory RNAs have been found to be incapable of protein coding and are hence termed as non-coding RNAs (ncRNAs). However, studies in recent years have shown that several previously annotated non-coding RNAs have the potential to encode proteins, and conversely, some coding RNAs have regulatory functions independent of the protein they encode. Such bi-functional RNAs, with both protein coding and non-coding functions, which we term as ‘cncRNAs’, have emerged as new players in cellular systems. Here, we describe the functions of some cncRNAs identified from bacteria to humans. Because the functions of many RNAs across genomes remains unclear, we propose that RNAs be classified as coding, non-coding or both only after careful analysis of their functions. PMID:26498036

  15. Investigation on Effect of Material Hardness in High Speed CNC End Milling Process

    PubMed Central

    Dhandapani, N. V.; Thangarasu, V. S.; Sureshkannan, G.

    2015-01-01

    This research paper analyzes the effects of material properties on surface roughness, material removal rate, and tool wear on high speed CNC end milling process with various ferrous and nonferrous materials. The challenge of material specific decision on the process parameters of spindle speed, feed rate, depth of cut, coolant flow rate, cutting tool material, and type of coating for the cutting tool for required quality and quantity of production is addressed. Generally, decision made by the operator on floor is based on suggested values of the tool manufacturer or by trial and error method. This paper describes effect of various parameters on the surface roughness characteristics of the precision machining part. The prediction method suggested is based on various experimental analysis of parameters in different compositions of input conditions which would benefit the industry on standardization of high speed CNC end milling processes. The results show a basis for selection of parameters to get better results of surface roughness values as predicted by the case study results. PMID:26881267

  16. Research on test techniques of fault forewarning and diagnosis for high-end CNC machine tool

    NASA Astrophysics Data System (ADS)

    Ren, Bin; Xu, Xiaoli

    2010-12-01

    With the progress of modern science and technique, the manufacturing industry becomes more and more complex and intelligent. It is the challenge for stable, safe running and economical efficiency of machining equipment such as high-quality numerical control because of its complex structure and integrated functions, and the potential faults are easy to happen. How to ensure the equipment runs stably and reliably becomes the key problem to improve the machining precision and efficiency. In order to prolong the average no-fault time, stable running and machining precision of numerical control, it is very important to make relative test and research on acquisition of data of numerical control sample and establishment of sample database. Take high-end CNC Machine Tool for example, the research on test techniques for data acquisition of sample of typical functional parts in CNC Machine Tool will be made and test condition will be set up; the test methods for sample acquisition on running state monitoring and fault forewarning and diagnosis of numerical control is determined; the test platform for typical functional parts of numerical control is established; the sample database is designed and the sample base and knowledge mode is made. The test and research provide key test techniques to disclosure dynamic performance of fault and precision degeneration, and analyze the impact factors to fault.

  17. The Multi-Scale Environment of RS Cnc from CO and HI Observations

    NASA Astrophysics Data System (ADS)

    Hoai, D. T.; Matthews, L. D.; Winters, J. M.; Nhung, P. T.; Gérard, E.; Libert, Y.; Le Bertre, T.

    2015-08-01

    We present a detailed study of the circumstellar gas distribution and kinematics of the semi-regular variable star RS Cnc on spatial scales ranging from ˜1″ (˜150 AU) to ˜6' (˜0.24 pc). The close environment of RS Cnc (from 1 to 20″) can be described with a model in which the density and velocity vary smoothly from the equatorial plane to the polar axis. In this model the mass loss rate is higher along the polar directions than in the equatorial plane, which does not favor current models invoking stellar rotation or a magnetic field as the cause of the axi-symmetry. Outside this region, the study of which is limited by the photo-dissociation of CO, HI data at 21 cm show that the flow is slowed down at a typical distance of 1' (˜0.04 pc). Further away (1 to 6', or 0.04 to 0.24 pc), the flow is distorted by the relative motion of the star with respect to the interstellar medium.

  18. Placement of the material temperature sensor during measuring the accuracy of CNC machine tools

    NASA Astrophysics Data System (ADS)

    Zhao, Dong-sheng; Jia, Min-qiang; Zhang, Jian; Sun, Lei; Li, Wei-jun

    2013-10-01

    In view of the dispute on the placement of material sensor when measuring the positional accuracy of a linear axis of a CNC machine tool, this paper presents the method and principle of deciding where to put the material temperature sensor. The positional accuracy of the linear axis of the machine tool is one of the most important performance parameters, and it must be measured when setup and check. The placement of the material temperature sensor has great influence on the measurement accuracy. At present, there are two main views on this issue: one is to place the sensor on the table of the machine tool, the other is to place it on the feedback system. This conflict between these two debates often makes the measurers feel confused and as a result influences the measure quality, sometimes. This thesis attempts to classify the CNC machine tools positional accuracy measurement according to its different purposes, then further presents the best placement. The thesis also elaborates other relevant questions of the placement of the material temperature sensor.

  19. AT Cnc: A Second Dwarf Nova with a Classical Nova Shell

    NASA Astrophysics Data System (ADS)

    Shara, Michael M.; Mizusawa, Trisha; Wehinger, Peter; Zurek, David; Martin, Christopher D.; Neill, James D.; Forster, Karl; Seibert, Mark

    2012-10-01

    We are systematically surveying all known and suspected Z Cam-type dwarf novae for classical nova shells. This survey is motivated by the discovery of the largest known classical nova shell, which surrounds the archetypal dwarf nova Z Camelopardalis. The Z Cam shell demonstrates that at least some dwarf novae must have undergone classical nova eruptions in the past, and that at least some classical novae become dwarf novae long after their nova thermonuclear outbursts, in accord with the hibernation scenario of cataclysmic binaries. Here we report the detection of a fragmented "shell," 3 arcmin in diameter, surrounding the dwarf nova AT Cancri. This second discovery demonstrates that nova shells surrounding Z Cam-type dwarf novae cannot be very rare. The shell geometry is suggestive of bipolar, conical ejection seen nearly pole-on. A spectrum of the brightest AT Cnc shell knot is similar to that of the ejecta of the classical nova GK Per, and of Z Cam, dominated by [N II] emission. Galaxy Evolution Explorer FUV imagery reveals a similar-sized, FUV-emitting shell. We determine a distance of 460 pc to AT Cnc, and an upper limit to its ejecta mass of ~5 × 10-5 M ⊙, typical of classical novae.

  20. Step-and-Repeat Nanoimprint-, Photo- and Laser Lithography from One Customised CNC Machine

    NASA Astrophysics Data System (ADS)

    Greer, Andrew IM; Della-Rosa, Benoit; Khokhar, Ali Z.; Gadegaard, Nikolaj

    2016-03-01

    The conversion of a computer numerical control machine into a nanoimprint step-and-repeat tool with additional laser- and photolithography capacity is documented here. All three processes, each demonstrated on a variety of photoresists, are performed successfully and analysed so as to enable the reader to relate their known lithography process(es) to the findings. Using the converted tool, 1 cm2 of nanopattern may be exposed in 6 s, over 3300 times faster than the electron beam equivalent. Nanoimprint tools are commercially available, but these can cost around 1000 times more than this customised computer numerical control (CNC) machine. The converted equipment facilitates rapid production and large area micro- and nanoscale research on small grants, ultimately enabling faster and more diverse growth in this field of science. In comparison to commercial tools, this converted CNC also boasts capacity to handle larger substrates, temperature control and active force control, up to ten times more curing dose and compactness. Actual devices are fabricated using the machine including an expanded nanotopographic array and microfluidic PDMS Y-channel mixers.

  1. GROUND-BASED TRANSIT OBSERVATIONS OF THE SUPER-EARTH 55 Cnc e

    SciTech Connect

    De Mooij, E. J. W.; López-Morales, M.; Karjalainen, R.; Hrudkova, M.; Jayawardhana, Ray

    2014-12-20

    We report the first ground-based detections of the shallow transit of the super-Earth exoplanet 55 Cnc e using a 2 m class telescope. Using differential spectrophotometry, we observed one transit in 2013 and another in 2014, with average spectral resolutions of ∼700 and ∼250, spanning the Johnson BVR photometric bands. We find a white light planet-to-star radius ratio of 0.0190{sub −0.0027}{sup +0.0023} from the 2013 observations and 0.0200{sub −0.0018}{sup +0.0017} from the 2014 observations. The two data sets combined result in a radius ratio of 0.0198{sub −0.0014}{sup +0.0013}. These values are all in agreement with previous space-based results. Scintillation noise in the data prevents us from placing strong constraints on the presence of an extended hydrogen-rich atmosphere. Nevertheless, our detections of 55 Cnc e in transit demonstrate that moderate-sized telescopes on the ground will be capable of routine follow-up observations of super-Earth candidates discovered by the Transiting Exoplanet Survey Satellite around bright stars. We expect it also will be possible to place constraints on the atmospheric characteristics of those planets by devising observational strategies to minimize scintillation noise.

  2. Overview of Sustainability Studies of CNC Machining and LAM of Stainless Steel

    NASA Astrophysics Data System (ADS)

    Nyamekye, Patricia; Leino, Maija; Piili, Heidi; Salminen, Antti

    Laser additive manufacturing (LAM), known also as 3D printing, is a powder bed fusion (PBF) type of additive manufacturing (AM) technology used to fabricate metal parts out of metal powder. The development of the technology from building prototype parts to functional parts has increased remarkably in 2000s. LAM of metals is promising technology that offers new opportunities to manufacturing and to resource efficiency. However, there is only few published articles about its sustainability. Aim in this study was to create supply chain model of LAM and CNC machining and create a methodology to carry out a life cycle inventory (LCI) data collection for these techniques. The methodology of the study was literature review and scenario modeling. The acquisition of raw material, production phase and transportations were used as basis of comparison. The modelled scenarios were fictitious and created for industries, like aviation and healthcare that often require swift delivery as well as customized parts. The results of this study showed that the use of LAM offers a possibility to reduce downtime in supply chains of spare parts and reduce part inventory more effectively than CNC machining. Also the gap between customers and business is possible to be shortened with LAM thus offering a possibility to reduce emissions due to less transportation. The results also indicated weight reduction possibility with LAM due to optimized part geometry which allow lesser amount of metallic powder to be used in making parts.

  3. Superhumps and Reflares in the WZ Sge-Type Dwarf Nova EG CNC

    NASA Astrophysics Data System (ADS)

    Kato, T.; Nogami, D.; Baba, H.; Masuda, S.; Matsumoto, K.

    EG Cnc is a dwarf nova discovered by Huruhata (1983). No outbursts had been confirmed until 1996 since its last in 1977. The long interval between outbursts and the large (~8 mag) outburst amplitude have strongly suggested that this star belongs to the rare class of WZ Sge-type dwarf novae consisting of only three secure members. Upon VSNET alert on the detection of its second historical outburst by P. Schmeer on 1996 Dec. 30, we undertook extensive CCD photometry using the Osaka Kyoiku University 51 cm telescope and the Ouda 60 cm telescope. Our observation has revealed the existence of two distinct types of superhumps just as were observed in other WZ Sge-type members, WZ Sge and AL Com. The object further showed, for the first time in the history of dwarf novae, repeated ``mini-outbursts" or reflares after its main superoutburst. We discuss from this new observational finding on the relationship between the repeated reflares in EG Cnc and the double superoutburst in AL Com, with a possible implication on the mechanism of similar ``mini-outbursts" observed in the black hole-candidate X-ray transient GRO J0422+32.

  4. AT Cnc: A SECOND DWARF NOVA WITH A CLASSICAL NOVA SHELL

    SciTech Connect

    Shara, Michael M.; Mizusawa, Trisha; Zurek, David; Wehinger, Peter; Martin, Christopher D.; Neill, James D.; Forster, Karl; Seibert, Mark

    2012-10-20

    We are systematically surveying all known and suspected Z Cam-type dwarf novae for classical nova shells. This survey is motivated by the discovery of the largest known classical nova shell, which surrounds the archetypal dwarf nova Z Camelopardalis. The Z Cam shell demonstrates that at least some dwarf novae must have undergone classical nova eruptions in the past, and that at least some classical novae become dwarf novae long after their nova thermonuclear outbursts, in accord with the hibernation scenario of cataclysmic binaries. Here we report the detection of a fragmented 'shell', 3 arcmin in diameter, surrounding the dwarf nova AT Cancri. This second discovery demonstrates that nova shells surrounding Z Cam-type dwarf novae cannot be very rare. The shell geometry is suggestive of bipolar, conical ejection seen nearly pole-on. A spectrum of the brightest AT Cnc shell knot is similar to that of the ejecta of the classical nova GK Per, and of Z Cam, dominated by [N II] emission. Galaxy Evolution Explorer FUV imagery reveals a similar-sized, FUV-emitting shell. We determine a distance of 460 pc to AT Cnc, and an upper limit to its ejecta mass of {approx}5 Multiplication-Sign 10{sup -5} M {sub Sun }, typical of classical novae.

  5. Fast manufacturing of E-ELT mirror segments using CNC polishing

    NASA Astrophysics Data System (ADS)

    Gray, C.; Baker, I.; Davies, G.; Evans, R.; Field, N.; Fox-Leonard, T.; Messelink, W.; Mitchell, J.; Rees, P.; Waine, S.; Walker, D. D.; Yu, G.

    2013-09-01

    We report on the first-ever demonstration of grinding and polishing full-size, off-axis aspheric, mirror segments as prototypes for an extremely large telescope, processed entirely in the final hexagonal shape. We first describe the overall strategy for controlling form and mid spatial frequencies, at levels in the vicinity of <10nm RMS surface. This relies first on direct CNC grinding of the base-form of these 1.4m segments, using the Cranfield BoX™ machine. The segments are then mounted on a custom designed (Optic Glyndwr Optoelectronic Engineering Group) three segment hydraulic support, and CNC polished on a Zeeko IRP 1600 machine using a variety of custom tooling. We overview the fullaperture and sub-aperture metrology techniques used to close the process-loop and certify quality, all of which operate with the segment in-situ on the IRP1600. We then focus on the pristine edge-definition achieved by the combination of tool-lift and smoothing operations; results never previously demonstrated on full-size pre-cut hexagonal segments. Finally, the paper discusses the feasibility of scaling the process to deliver 931 segments in seven years, as required for the E-ELT project.

  6. Step-and-Repeat Nanoimprint-, Photo- and Laser Lithography from One Customised CNC Machine.

    PubMed

    Greer, Andrew Im; Della-Rosa, Benoit; Khokhar, Ali Z; Gadegaard, Nikolaj

    2016-12-01

    The conversion of a computer numerical control machine into a nanoimprint step-and-repeat tool with additional laser- and photolithography capacity is documented here. All three processes, each demonstrated on a variety of photoresists, are performed successfully and analysed so as to enable the reader to relate their known lithography process(es) to the findings. Using the converted tool, 1 cm(2) of nanopattern may be exposed in 6 s, over 3300 times faster than the electron beam equivalent. Nanoimprint tools are commercially available, but these can cost around 1000 times more than this customised computer numerical control (CNC) machine. The converted equipment facilitates rapid production and large area micro- and nanoscale research on small grants, ultimately enabling faster and more diverse growth in this field of science. In comparison to commercial tools, this converted CNC also boasts capacity to handle larger substrates, temperature control and active force control, up to ten times more curing dose and compactness. Actual devices are fabricated using the machine including an expanded nanotopographic array and microfluidic PDMS Y-channel mixers. PMID:26956598

  7. Investigation on Effect of Material Hardness in High Speed CNC End Milling Process.

    PubMed

    Dhandapani, N V; Thangarasu, V S; Sureshkannan, G

    2015-01-01

    This research paper analyzes the effects of material properties on surface roughness, material removal rate, and tool wear on high speed CNC end milling process with various ferrous and nonferrous materials. The challenge of material specific decision on the process parameters of spindle speed, feed rate, depth of cut, coolant flow rate, cutting tool material, and type of coating for the cutting tool for required quality and quantity of production is addressed. Generally, decision made by the operator on floor is based on suggested values of the tool manufacturer or by trial and error method. This paper describes effect of various parameters on the surface roughness characteristics of the precision machining part. The prediction method suggested is based on various experimental analysis of parameters in different compositions of input conditions which would benefit the industry on standardization of high speed CNC end milling processes. The results show a basis for selection of parameters to get better results of surface roughness values as predicted by the case study results. PMID:26881267

  8. West Flank Coso, CA FORGE 3D temperature model

    DOE Data Explorer

    Doug Blankenship

    2016-03-01

    x,y,z data of the 3D temperature model for the West Flank Coso FORGE site. Model grid spacing is 250m. The temperature model for the Coso geothermal field used over 100 geothermal production sized wells and intermediate-depth temperature holes. At the near surface of this model, two boundary temperatures were assumed: (1) areas with surface manifestations, including fumaroles along the northeast striking normal faults and northwest striking dextral faults with the hydrothermal field, a temperature of ~104˚C was applied to datum at +1066 meters above sea level elevation, and (2) a near-surface temperature at about 10 meters depth, of 20˚C was applied below the diurnal and annual conductive temperature perturbations. These assumptions were based on heat flow studies conducted at the CVF and for the Mojave Desert. On the edges of the hydrothermal system, a 73˚C/km (4˚F/100’) temperature gradient contour was established using conductive gradient data from shallow and intermediate-depth temperature holes. This contour was continued to all elevation datums between the 20˚C surface and -1520 meters below mean sea level. Because the West Flank is outside of the geothermal field footprint, during Phase 1, the three wells inside the FORGE site were incorporated into the preexisting temperature model. To ensure a complete model was built based on all the available data sets, measured bottom-hole temperature gradients in certain wells were downward extrapolated to the next deepest elevation datum (or a maximum of about 25% of the well depth where conductive gradients are evident in the lower portions of the wells). After assuring that the margins of the geothermal field were going to be adequately modelled, the data was contoured using the Kriging method algorithm. Although the extrapolated temperatures and boundary conditions are not rigorous, the calculated temperatures are anticipated to be within ~6˚C (20˚F), or one contour interval, of the

  9. Implications of Flexural Flanks at the Valles Marineris, Mars

    NASA Technical Reports Server (NTRS)

    Anderson, F. S.; Banerdt, W. B.; Golombek, M. P.

    1999-01-01

    The presence or absence of flexural flanks at the Valles Marineris (VM), Mars, have strong implications for the properties of the lithosphere, information which is critical for models of compensation state and formation of the troughs. Two hypotheses are favored for the formation of the VM, tectonic extension or subsurface withdrawal potentially related to dike emplacement; in either case, the formation of the large troughs at the VM requires a flexural response. After discussing preliminary models of flexure for VM from released Mars Global Surveyor (MGS) Mars Orbiting Laser Altimeter (MOLA) topography, this abstract considers the implications of flexure for gravity modeling and the lithosphere at VM. With future MGS topography and gravity data, and constraints on T(sub e) from this study, significantly better gravity modeling can be done to understand the state of the lithosphere at VM. Additional information is contained in the original extended abstract.

  10. The 5' flanking region of human epsilon-globin gene.

    PubMed Central

    Baralle, F E; Shoulders, C C; Goodbourn, S; Jeffreys, A; Proudfoot, N J

    1980-01-01

    The structural analysis of the 2.0 kb region upstream from the epsilon-globin gene has been carried out. A genomic DNA map around the gene was worked out in some detail to ensure that the cloned DNA was representative of the actual chromosomal arrangement. Furthermore, a new technique was developed to precisely map a reiterated DNA sequence present 1.5 kb to the 5' side of the gene. The complete nucleotide sequence of the 2.0 kb 5' flanking region was then determined and overlapped with the gene. The sequence included the reiterated DNA sequence which is homologous to the so-called AluI family of repeats. Unusual stretches of sequence 50 nucleotides long, where A + T represent about 90% of the bases, are present at both the 5' and 3' sides of the repeat. Images PMID:6253916

  11. Bathymetry of the southwest flank of Mauna Loa Volcano, Hawaii

    USGS Publications Warehouse

    Chadwick, William W.; Moore, James G.; Fox, Christopher G.

    1994-01-01

    Much of the seafloor topography in the map area is on the southwest submarine flank of the currently active Mauna Loa Volcano. The benches and blocky hills shown on the map were shaped by giant landslides that resulted from instability of the rapidly growing volcano. These landslides were imagined during a 1986 to 1991 swath sonar program of the United States Hawaiian Exclusive Economic Zone, a cooperative venture by the U.S. Geological Survey and the British Institute of Oceanographic Sciences (Lipman and others, 1988; Moore and others, 1989). Dana Seamount (and probably also the neighboring Day Seamount) are apparently Cretaceous in age, based on paleomagnetic studies, and predate the growth of the Hawaiian Ridge volcanoes (Sager and Pringle, 1990).

  12. Evidence of Multiple Flank Collapse at Volcan Baru, Panama

    NASA Astrophysics Data System (ADS)

    Herrick, J. A.; Rose, W. I.

    2009-12-01

    Michigan Tech's Peace Corps Master's International program (PCMI) in Geological Hazards has enabled several long-term investigations of active volcanoes in Latin America. To contribute to volcanic hazard assessments in Panama and achieve the goals defined by the PCMI program, we developed this debris avalanche project to address outstanding questions regarding Volcan Baru's most devastating event - massive slope failure of the western flank. Relying on basic mapping tools as well as the 2007 USGS Open-File Report focusing on hazard assessments of Panama's youngest and potentially active volcano, identification of the debris avalanche deposits (DAD) required detailed field investigations to determine the limits of the units. Extending across an area larger than 600 km2, field strategies were developed based on outcrop exposures within drainages and road-cuts. Aerial photos and DEMs of Baru's nested craters were interpreted by earlier scientists as the remains of two collapsed flanks. The results from in-depth field traverses provide several important discoveries: paleosols and sharp contacts within the stratigraphy indicate multiple DAD, deeply weathered hummocks red-flag the deposits more than 50-km away from Baru's crater, and high-quality radiocarbon samples (up to 45-cm long fragments of entrained wood) lie in the distal reaches of the debris flow area. During the 2008-2009 field seasons, we received assistance from the University of Panama, Civil Protection, and Panama's National Institute of Geography. Support from local experts and feedback from professional scientists of the Smithsonian Institution and Costa Rica's Institute of Electricity were invaluable. The 2-year investment in volcanic hazard studies has brought together resources from several countries as well as fresh data that will benefit the residents and emergency management officials of Panama. Jigsaw fractured clasts lie within Volcan Baru's debris avalanche deposits more than 28 km south of the

  13. Dyke and sill injections: what mostly trigger volcano flank collapse?

    NASA Astrophysics Data System (ADS)

    Catry, Thibault; Cayol, Valérie; Michon, Laurent; Famin, Vincent; Romagnoli, Claudia; Chaput, Marie

    2010-05-01

    There is a large number of evidences that the morphostructural evolution of basaltic oceanic volcanoes (e.g. Stromboli, Hawaï and Canary Islands) results of alternating phases of growth and destruction. Among dismantling processes, flank collapses have been largely documented and interpreted as gravitational destabilization triggered by vertical injections of magma (dykes). In most cases, this interpretation has not been sustained by field observations because active volcanoes have poor occurrence of outcropped intrusions. From this point of view, Piton des Neiges volcano (La Réunion Island) represents a case in point because it has been deeply incised by erosion, providing large outcropped surfaces exhibiting the geometrical relationship between intrusions and host volcanic formations. The recent discovery of a highly deformed pile of sills at the interface between a debris avalanche deposit and a fossilized magma chamber brought to light the role of horizontal injections in the triggering of lateral collapses. The validation of this assumption rests on a digital model developed from the Mixed Boundary Element Method of elastic deformation field analysis. In this study, we modelled the intensity and the distribution of deformation and Coulomb stresses perturbation due to the injection of dykes along rift zones and a sill below the flank of a basaltic volcano. We quantified the influence of the intrusions in the mechanical state of the edifice, based on the deformation detected during an intrusion of magma at Piton de la Fournaise volcano. By comparing the deformation generated by sills to that generated by dykes, our modelling approach concludes that the area deformed by a sill injection is much wider than that deformed by a dyke injection. Moreover, we found that sill injection reaches higher intensities of lateral displacements. The combination of field data and our modelling results suggests therefore that repeated sill injection is an underestimated trigger

  14. Erosion of Terrestrial Rift Flank Topography: A Quantitative Study

    NASA Technical Reports Server (NTRS)

    Weissel, Jeffrey K.

    1999-01-01

    Many rifted or passive continental margins feature a seaward-facing erosional escarpment which abruptly demarcates deeply weathered, low relief, interior uplands from a deeply incised, high relief coastal zone. It is generally accepted that these escarpments originate at the time of continental rifting and propagate inland through the elevated rift flank topography at rates on the order of 1 km/Myr over the course of a margin's history. Considering the length of passive margins worldwide and an average rift flank plateau height of several hundred meters, it is clear that sediment eroded from passive margins is an important component of the mass flux from continents to oceans through geologic time. The overall goal of the research reported here is to develop a quantitative understanding of the kinematics of escarpment propagation across passive margins and the underlying geological processes responsible for this behavior. Plateau-bounding escarpments in general exhibit two basic forms depending on the direction of surface water drainage on the plateau interior relative to the escarpment. Where surface water flows away from the escarpment, the escarpment takes the form of subdued embayments and promontories, such that its overall trend remains fairly straight as it evolves with time. Where upland streams flow across the escarpment, it takes the form of dramatic, narrow gorges whose heads appear to propagate up the plateau drainage systems as large-scale knickpoints. From work on the Colorado Plateau, Schmidt (1987) noted that the Colorado River is located much closer to the Grand Canyon's south rim, a drainage divide escarpment, than to the north rim, which is a gorge-like escarpment. The main implication is that the gorge-like form might be associated with higher long-term average erosion rates compared to the drainage divide escarpment type.

  15. Preparation of the CNC/Ag/beeswax composites for enhancing antibacterial and water resistance properties of paper.

    PubMed

    Liu, Kai; Liang, Hunan; Nasrallah, Joseph; Chen, Lihui; Huang, Liulian; Ni, Yonghao

    2016-05-20

    An effective method of preparing composites containing inorganic (Ag) and organic (beeswax) particles was established in this study. Ag nanoparticles were first immobilized on the cellulose nanocrystals (CNC) during the reduction of AgNO3 in the presence of CNC, then mixed with beeswax by high speed stirring. Scanning transmission electron microscopy (STEM) images indicated that Ag and beeswax particles were uniformly dispersed and stable in the network structure formed by CNC. Upon coating on a paper surface, a layer of beeswax film was evident based on scanning electron microscopy (SEM) images. The dynamic contact angle and antibacterial activity tests indicated that the contact angle of coated paper reached 113.06° and the growth inhibition of Escherichia coli increased to 99.96%, respectively, at a coating amount of 21.53 g/m(2). When applied onto paper surface by coating, the CNC/Ag/beeswax composites can impact paper with antibacterial property and improved water resistance. PMID:26917389

  16. Advanced CNC and CAM Series. Educational Resources for the Machine Tool Industry. Course Syllabi, Instructor's Handbook [and] Student Laboratory Manual.

    ERIC Educational Resources Information Center

    Texas State Technical Coll. System, Waco.

    This package consists of course syllabi, an instructor's handbook, and student laboratory manual for a 1-year vocational training program to prepare students for entry-level positions as advanced computer numerical control (CNC) and computer-assisted manufacturing (CAM) technicians.. The program was developed through a modification of the DACUM…

  17. Comprehensive reliability allocation method for CNC lathes based on cubic transformed functions of failure mode and effects analysis

    NASA Astrophysics Data System (ADS)

    Yang, Zhou; Zhu, Yunpeng; Ren, Hongrui; Zhang, Yimin

    2015-03-01

    Reliability allocation of computerized numerical controlled(CNC) lathes is very important in industry. Traditional allocation methods only focus on high-failure rate components rather than moderate failure rate components, which is not applicable in some conditions. Aiming at solving the problem of CNC lathes reliability allocating, a comprehensive reliability allocation method based on cubic transformed functions of failure modes and effects analysis(FMEA) is presented. Firstly, conventional reliability allocation methods are introduced. Then the limitations of direct combination of comprehensive allocation method with the exponential transformed FMEA method are investigated. Subsequently, a cubic transformed function is established in order to overcome these limitations. Properties of the new transformed functions are discussed by considering the failure severity and the failure occurrence. Designers can choose appropriate transform amplitudes according to their requirements. Finally, a CNC lathe and a spindle system are used as an example to verify the new allocation method. Seven criteria are considered to compare the results of the new method with traditional methods. The allocation results indicate that the new method is more flexible than traditional methods. By employing the new cubic transformed function, the method covers a wider range of problems in CNC reliability allocation without losing the advantages of traditional methods.

  18. The Structure and Principles of Work Intellectual Processing Control System on CNC

    NASA Astrophysics Data System (ADS)

    Nekrasov, R. Y.; Putilova, U. S.; Starikov, A. I.; Soloviev, I. V.; Bekareva, O. V.

    2016-04-01

    The high rate of technological progress imposes stringent quality demands of engineering production. The main requirement is dimensional accuracy of metal-cutting equipment with a minimal needed operating costs during the period of operation. The article considers the problem of increasing the accuracy of processing engineering products on CNC. The authors have proposed a solution of the problem by providing entering operational adjustment to the control of the trajectory of the executive bodies of the machine. The necessity of creation of mathematical models of processes in an automated process system operations (APSO). Based on the research, authors had proposed that a generalized scheme of diagnosis and operation input of corrections and approximate mathematical models of the individual processes of diagnosis.

  19. Study on grinding of free-form optics surface in three-axis CNC machine

    NASA Astrophysics Data System (ADS)

    Yang, Haicheng; Zhang, Yun-long; Zhang, Feng; Wang, Zhibin; Bao, Long-xiang; Su, Ying; Guo, Rui; Liu, Xuan-min

    2014-08-01

    Due to the glass is a type of brittle material, so the high-precision free-form optics of glass material is usually machined by the technical of grinding. In this paper, for the characteristics of the diamond grinding wheel, analyzing the grinding path of free-form optics and mathematical model of the path is established based on the three-axis CNC grinding device. Moreover, the cause of the interference in the process of grinding is analyzed and the methods of avoiding. Finally, based on the above analysis results, through the experiment, the free-form optics surface accuracy was reached to 3.6um, realize the machining of the free-form optics.

  20. Concurrent Collections (CnC): A new approach to parallel programming

    SciTech Connect

    2010-05-07

    A common approach in designing parallel languages is to provide some high level handles to manipulate the use of the parallel platform. This exposes some aspects of the target platform, for example, shared vs. distributed memory. It may expose some but not all types of parallelism, for example, data parallelism but not task parallelism. This approach must find a balance between the desire to provide a simple view for the domain expert and provide sufficient power for tuning. This is hard for any given architecture and harder if the language is to apply to a range of architectures. Either simplicity or power is lost. Instead of viewing the language design problem as one of providing the programmer with high level handles, we view the problem as one of designing an interface. On one side of this interface is the programmer (domain expert) who knows the application but needs no knowledge of any aspects of the platform. On the other side of the interface is the performance expert (programmer or program) who demands maximal flexibility for optimizing the mapping to a wide range of target platforms (parallel / serial, shared / distributed, homogeneous / heterogeneous, etc.) but needs no knowledge of the domain. Concurrent Collections (CnC) is based on this separation of concerns. The talk will present CnC and its benefits. About the speaker Kathleen Knobe has focused throughout her career on parallelism especially compiler technology, runtime system design and language design. She worked at Compass (aka Massachusetts Computer Associates) from 1980 to 1991 designing compilers for a wide range of parallel platforms for Thinking Machines, MasPar, Alliant, Numerix, and several government projects. In 1991 she decided to finish her education. After graduating from MIT in 1997, she joined Digital Equipment’s Cambridge Research Lab (CRL). She stayed through the DEC/Compaq/HP mergers and when CRL was acquired and absorbed by Intel. She currently works in the Software and

  1. Concurrent Collections (CnC): A new approach to parallel programming

    ScienceCinema

    None

    2011-10-06

    A common approach in designing parallel languages is to provide some high level handles to manipulate the use of the parallel platform. This exposes some aspects of the target platform, for example, shared vs. distributed memory. It may expose some but not all types of parallelism, for example, data parallelism but not task parallelism. This approach must find a balance between the desire to provide a simple view for the domain expert and provide sufficient power for tuning. This is hard for any given architecture and harder if the language is to apply to a range of architectures. Either simplicity or power is lost. Instead of viewing the language design problem as one of providing the programmer with high level handles, we view the problem as one of designing an interface. On one side of this interface is the programmer (domain expert) who knows the application but needs no knowledge of any aspects of the platform. On the other side of the interface is the performance expert (programmer or program) who demands maximal flexibility for optimizing the mapping to a wide range of target platforms (parallel / serial, shared / distributed, homogeneous / heterogeneous, etc.) but needs no knowledge of the domain. Concurrent Collections (CnC) is based on this separation of concerns. The talk will present CnC and its benefits. About the speaker Kathleen Knobe has focused throughout her career on parallelism especially compiler technology, runtime system design and language design. She worked at Compass (aka Massachusetts Computer Associates) from 1980 to 1991 designing compilers for a wide range of parallel platforms for Thinking Machines, MasPar, Alliant, Numerix, and several government projects. In 1991 she decided to finish her education. After graduating from MIT in 1997, she joined Digital Equipment?s Cambridge Research Lab (CRL). She stayed through the DEC/Compaq/HP mergers and when CRL was acquired and absorbed by Intel. She currently works in the Software and

  2. 3D FEM Simulation of Flank Wear in Turning

    NASA Astrophysics Data System (ADS)

    Attanasio, Aldo; Ceretti, Elisabetta; Giardini, Claudio

    2011-05-01

    This work deals with tool wear simulation. Studying the influence of tool wear on tool life, tool substitution policy and influence on final part quality, surface integrity, cutting forces and power consumption it is important to reduce the global process costs. Adhesion, abrasion, erosion, diffusion, corrosion and fracture are some of the phenomena responsible of the tool wear depending on the selected cutting parameters: cutting velocity, feed rate, depth of cut, …. In some cases these wear mechanisms are described by analytical models as a function of process variables (temperature, pressure and sliding velocity along the cutting surface). These analytical models are suitable to be implemented in FEM codes and they can be utilized to simulate the tool wear. In the present paper a commercial 3D FEM software has been customized to simulate the tool wear during turning operations when cutting AISI 1045 carbon steel with uncoated tungsten carbide tip. The FEM software was improved by means of a suitable subroutine able to modify the tool geometry on the basis of the estimated tool wear as the simulation goes on. Since for the considered couple of tool-workpiece material the main phenomena generating wear are the abrasive and the diffusive ones, the tool wear model implemented into the subroutine was obtained as combination between the Usui's and the Takeyama and Murata's models. A comparison between experimental and simulated flank tool wear curves is reported demonstrating that it is possible to simulate the tool wear development.

  3. Flank crack detection in locomotive wheels with NDE techniques

    NASA Astrophysics Data System (ADS)

    Laczynski, Marie; Jayaraman, Subash B.; Halter, Ryan; Tittmann, Bernhard R.

    2001-08-01

    There is a need to analyze locomotive wheels for flank cracks in a non-destructive manner in order to prevent catastrophic failures. Flaw, shape, and size are desired parameters in establishing the quality of commercial tires. A variety of defects such as voids, inclusions, surface and internal cracks, or the like, must be discerned in order to prevent failure. This paper exhibits and compares the benefits of a number of different techniques used for flaw detection. Non-destructive evaluation techniques used consist of a magnetic particle, dye penetrant, eddy current, electro-magnetic acoustic transducer (EMAT), and longitudinal and shear wave ultrasonic inspection. The techniques vary in their ability to ascertain the flaw characteristics. Surface, sub-surface, and internal defects were visualized using the various methodologies. Magnetic particle, dye penetrant, and eddy current inspection techniques are viable methods for looking at surface flaws. Depending on the penetration depth, sub- surface flaws were also detectable via these methods. EMAT and ultrasonic transducer methods can be used to find surface, subsurface, and internal flaws based on the configuration utilized.

  4. Open Mini-Flank Partial Nephrectomy: An Essential Contemporary Operation

    PubMed Central

    Mano, Roy

    2014-01-01

    Secondary to the widespread use of the modern imaging techniques of computed tomography, magnetic resonance imaging, and ultrasound, 70% of renal tumors today are detected incidentally with a median tumor size of less than 4 cm. Twenty years ago, all renal tumors, regardless of size were treated with radical nephrectomy (RN). Elective partial nephrectomy (PN) has emerged as the treatment of choice for small renal tumors. The basis of this paradigm shift is three major factors: (1) cancer specific survival is equivalent for T1 tumors (7 cm or less) whether treated by PN or RN; (2) approximately 45% of renal tumors have indolent or benign pathology; and (3) PN prevents or delays the onset of chronic kidney disease, a condition associated with increased cardiovascular morbidity and mortality. Although PN can be technically demanding and associated with potential complications of bleeding, infection, and urinary fistula, the patient derived benefits of this operation far outweigh the risks. We have developed a "mini-flank" open surgical approach that is highly effective and, coupled with rapid recovery postoperative care pathways associated with a 2-day length of hospital stay. PMID:25237456

  5. The cag-pathogenicity island encoded CncR1 sRNA oppositely modulates Helicobacter pylori motility and adhesion to host cells.

    PubMed

    Vannini, Andrea; Roncarati, Davide; Danielli, Alberto

    2016-08-01

    Small regulatory RNAs (sRNAs) are emerging as key post-transcriptional regulators in many bacteria. In the human pathobiont Helicobacter pylori a plethora of trans- and cis-encoded sRNAs have been pinpointed by a global transcriptome study. However, only two have been studied in depth at the functional level. Here we report the characterization of CncR1, an abundant and conserved sRNA encoded by the virulence-associated cag pathogenicity island (cag-PAI) of H. pylori. Growth-phase dependent transcription of CncR1 is directed by the PcagP promoter, which resulted to be a target of the essential transcriptional regulator HsrA (HP1043). We demonstrate that the 213 nt transcript arising from this promoter ends at an intrinsic terminator, few bases upstream of the annotated cagP open reading frame, establishing CncR1 as the predominant gene product encoded by the cagP (cag15) locus. Interestingly, the deletion of the locus resulted in the deregulation en masse of σ(54)-dependent genes, linking CncR1 to flagellar functions. Accordingly, the enhanced motility recorded for cncR1 deletion mutants was complemented by ectopic reintroduction of the allele in trans. In silico prediction identified fliK, encoding a flagellar checkpoint protein, as likely regulatory target of CncR1. The interaction of CncR1 with the fliK mRNA was thus further investigated in vitro, demonstrating the formation of strand-specific interactions between the two RNA molecules. Accordingly, the full-length translational fusions of fliK with a lux reporter gene were induced in a cncR1 deletion mutant in vivo. These data suggest the involvement of CncR1 in the post-transcriptional modulation of H. pylori motility functions through down-regulation of a critical flagellar checkpoint factor. Concurrently, the cncR1 mutant revealed a decrease of transcript levels for several H. pylori adhesins, resulting in a phenotypically significant impairment of bacterial adhesion to a host gastric cell line. The data

  6. Investigating Late Amazonian Volcanotectonic Activity on Olympus Mons, Mars using Flank Vents and Arcuate Graben

    NASA Astrophysics Data System (ADS)

    Peters, S.; Christensen, P. R.

    2015-12-01

    Volcanism, a fundamental process in shaping the Martian surface, is crucial to understanding its evolution. Olympus Mons, the largest volcano on Mars, is one of several large shield volcanoes. Previous studies were technologically limited to large features associated with these constructs. With the advent of high resolution datasets, we are now able to investigate smaller features, such as flank vents and arcuate graben. Flank vents, common on polygenetic volcanoes, indicate that magma has propagated away from the main conduit and/or magma chamber. Vent morphology allows for the characterization of magma properties and eruption rates. Graben indicate extensional deformation. The distribution of graben provides information on stresses that acted on the volcano. In lieu of geophysical, spectral and in-situ data, morphology, morphometry and spatial relationships are powerful tools. We utilized high resolution image data (CTX, HiRISE and THEMIS IR) and topographic data (HRSC DTM, MOLA) to identify and characterize flank vents and graben. We observed 60 flank vents and 84 arcuate graben on Olympus Mons. Flank vents display varying morphologies and morphometries, suggesting different eruption styles and variable magma volatility. Vents occur primarily on the lower flank. This suggests magma has propagated substantial distances from the magma chamber. Observed clustering of vents may also indicate shallow magma sources. Similarly, graben are observed on the lower flank crosscutting young lava flows that have mantled portions of the escarpment. This indicates either gravitational spreading of Olympus Mons or flexure of the lithosphere in response to the load of the edifice. Collectively, the distribution of flank vents and arcuate graben suggests a similar development to that proposed for Ascraeus Mons. Based on superposition relationships and dates from previous studies, the flank vents and graben formed in the Late Amazonian (≤500 Ma).

  7. A method for amplification of unknown flanking sequences based on touchdown PCR and suppression-PCR.

    PubMed

    Gao, Song; He, Dan; Li, Guangquan; Zhang, Yanhua; Lv, Huiying; Wang, Li

    2016-09-15

    Thermal asymmetric staggered PCR is the most widely used technique to obtain the flanking sequences. However, it has some limitations, including a low rate of positivity, and complex operation. In this study, a improved method of it was made based on suppression-PCR and touchdown PCR. The PCR fragment obtained by the amplification was used directly for sequencing after gel purification. Using this improved method, the positive rate of amplified flanking sequences of the ATMT mutants reached 99%. In addition, the time from DNA extraction to flanking sequence analysis was shortened to 2 days with about 6 dollars each sample. PMID:27393656

  8. Ovariectomy by left flank approach in prepubertal Nelore (Bos indicus) heifers

    PubMed Central

    Peiró, Juliana R.; Nogueira, Geison M.; Nogueira, Guilherme P.; Perri, Silvia H.V.; Cardoso, Daniel

    2009-01-01

    The main objective of this study was to evaluate a recumbent left flank approach to bilateral ovariectomy in prepubertal heifers and to develop an optimal surgical technique for this procedure. Both ovaries were removed from 6 Nelore heifers by left flank approach without any complications, except in 1 heifer, which was believed to have had only 1 ovary based on ultrasound and exploration during surgery, but was later found to have a remaining functional ovary. Ovariectomy via left flank approach in recumbent prepubertal heifers is feasible and technically easy. This procedure does not involve special instrumentation and, despite the invasive approach, it allows optimal visualization of the ovaries and uterus. PMID:19794897

  9. Cost minimizing of cutting process for CNC thermal and water-jet machines

    NASA Astrophysics Data System (ADS)

    Tavaeva, Anastasia; Kurennov, Dmitry

    2015-11-01

    This paper deals with optimization problem of cutting process for CNC thermal and water-jet machines. The accuracy of objective function parameters calculation for optimization problem is investigated. This paper shows that working tool path speed is not constant value. One depends on some parameters that are described in this paper. The relations of working tool path speed depending on the numbers of NC programs frames, length of straight cut, configuration part are presented. Based on received results the correction coefficients for working tool speed are defined. Additionally the optimization problem may be solved by using mathematical model. Model takes into account the additional restrictions of thermal cutting (choice of piercing and output tool point, precedence condition, thermal deformations). At the second part of paper the non-standard cutting techniques are considered. Ones may lead to minimizing of cutting cost and time compared with standard cutting techniques. This paper considers the effectiveness of non-standard cutting techniques application. At the end of the paper the future research works are indicated.

  10. Development of a CNC 5-kW CO2 laser processing equipment

    NASA Astrophysics Data System (ADS)

    Zhang, Shuren; Lu, Boliang; Zhang, Hongtao; Shao, Wushan

    1996-09-01

    This paper introduces the fundamental compositions and functions of a newly developed 5KW CO2 laser processing equipment CGJ-93 controlled by microcomputer in Changchun Institute of Optics and Fine Mechanics. The laser processing equipment consists of a 5KW CO2 laser, multifunction beam guidance systems, modular processing machine, water cooling system and CNC systems. The equipment has the ability to heat-treat not only the internal holes and outer circular surfaces but also space holes and three dimensional curved surfaces. The equipment can heat-treat workpieces up to 3000mm length, 1500mm diameter and 3000kg weight. The longitudinal table allows moving speed of 0.8-12000mm per minute with 3600mm effective moving range and 0.069mm position accuracy. The transverse table allows moving speed of 5-12000mm per minute with 1000mm effective moving range and 0.028mm position accuracy. The laser head allows longitudinal moving speed of 0.1-12000mm per minute. Its effective moving range and position accuracy are 540mm and 0.03mm respectively.

  11. Anharmonic Resonances among Low-Lying Vibrational Levels of Methyl Iso-Cyanide (H_3CNC)

    NASA Astrophysics Data System (ADS)

    Pracna, P.; Urban, J.; Urban, V. S.; Varga, J.; Horneman, V.-M.

    2010-06-01

    Vibrational levels up to 1000 wn of H_3C-N≡C are currently studied in FTIR spectra together with rotational transitions within these levels. This investigation comprises the low-lying excited vibrational levels of the CNC doubly degenerate bending vibration v8=1^± 1 (267.3 wn), v8=20,± 2 (524.6 wn (A), 545.3 wn (E)), and v8=3^± 1,± 3 (792.5 wn (A1+A2), 833.9 wn (E)), respectively, and the next higher fundamental level of the C-N valence vibration v4=1 (945 wn). All these vibrational levels exhibit cubic and quartic anharmonic resonances localized to moderate values of the rotational quantum number K≤10. Therefore the system of rovibrational levels has to be treated as a global polyad in order to describe all the available data quantitatively. The ground state constants have been improved considerably by extending the assignments to higher J/K rotational states both in the purely rotational spectra recorded in the ground vibrational level and in the ground state combination differences generated from the wavenumbers assigned in the fundamental ν_4 band. Similarities and differences with respect to isoelectronic molecules CH_3CN and CH_3CCH are discussed.

  12. Development of a CNC 5KW CO{sub 2} laser processing equipment

    SciTech Connect

    Zhang Shuren; Lu Boliang; Zhang Hong; Shao Wushan

    1996-12-31

    This paper introduces the fundamental compositions and functions of a newly developed 5KW CO{sub 2} laser processing equipment CGJ-93 controlled by microcomputer in CIOM (Changchun Institute of Optics and Fine Mechanics). The laser processing equipment consists of a 5KW CO{sub 2} laser, multifunction beam guidance system, modular processing machine, water cooling system and CNC system. The equipment has ability to heat-treat not only the internal holes and outer circular surfaces but also space holes and three dimensional curved surfaces. The equipment can heat-treat workpieces up to 3,000 mm length, 1,500mm diameter and 3,000kg weight. The longitudinal table allows moving speed of 0.8--12,000mm per minute with 3,600mm effective moving range and 0.069mm position accuracy. The transverse table allows moving speed of 5--1,2000mm per minute with 1,000mm effective moving range and 0.028 mm position accuracy. The laser head allows longitudinal moving speed of 0.1--1,2000mm per minute, its effective moving range and position accuracy are 540mm and 0.03mm respectively.

  13. An improved method for risk evaluation in failure modes and effects analysis of CNC lathe

    NASA Astrophysics Data System (ADS)

    Rachieru, N.; Belu, N.; Anghel, D. C.

    2015-11-01

    Failure mode and effects analysis (FMEA) is one of the most popular reliability analysis tools for identifying, assessing and eliminating potential failure modes in a wide range of industries. In general, failure modes in FMEA are evaluated and ranked through the risk priority number (RPN), which is obtained by the multiplication of crisp values of the risk factors, such as the occurrence (O), severity (S), and detection (D) of each failure mode. However, the crisp RPN method has been criticized to have several deficiencies. In this paper, linguistic variables, expressed in Gaussian, trapezoidal or triangular fuzzy numbers, are used to assess the ratings and weights for the risk factors S, O and D. A new risk assessment system based on the fuzzy set theory and fuzzy rule base theory is to be applied to assess and rank risks associated to failure modes that could appear in the functioning of Turn 55 Lathe CNC. Two case studies have been shown to demonstrate the methodology thus developed. It is illustrated a parallel between the results obtained by the traditional method and fuzzy logic for determining the RPNs. The results show that the proposed approach can reduce duplicated RPN numbers and get a more accurate, reasonable risk assessment. As a result, the stability of product and process can be assured.

  14. Design and manufacturing of cranioplasty implants by 3-axis cnc milling.

    PubMed

    Hieu, L C; Bohez, E; Vander Sloten, J; Oris, P; Phien, H N; Vatcharaporn, E; Binh, P H

    2002-01-01

    Although various techniques and materials have been used for making cranioplasty implants, personalized cranioplasty implants are high in cost because of expensive materials and production technology, long design and manufacturing time, and intensive labor use. This research was a part of our research project in ASEAN countries to investigate feasible technical solutions of minimizing the implant cost based on available production technologies in the region. The use of 3-axis CNC (Computer Numerical Control) milling techniques for making molds to fabricate PMMA implants was successfully investigated. With the development of a design support program bridging between Computer Aided Design (CAD) and Medical Image Processing (MIP) system, the time for geometrical modeling of implants and molds was reduced to half a day. The machining time to complete a mold was about 5 to 6 hours; and it took maximal 2 hours to fabricate an implant with self-curing PMMA and 3 and half hours for fabricating an implant with heat-curing PMMA. The cost of implants is acceptable for the ASEAN region. PMID:12368561

  15. Window type: 2x3 fixed multipaned steel window flanked by 1x3 ...

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

    Window type: 2x3 fixed multipaned steel window flanked by 1x3 multipaned steel casements. Concrete sill and spandrel also illustrated. Building 43, facing east - Harbor Hills Housing Project, 26607 Western Avenue, Lomita, Los Angeles County, CA

  16. Olympus Mons Aureole Deposits: New Evidence for a Flank Failure Origin

    NASA Technical Reports Server (NTRS)

    McGovern, P. J.; Smith, J. R.; Morgan, J. K.; Bulmer, M. H.

    2004-01-01

    The origin of the rough-textured aureoles that surround the immense Olympus Mons volcano on Mars is controversial. We present data from the Mars Global Surveyor and Mars Odyssey missions to demonstrate that at least two of the aureole lobes are derived from the volcano's flanks in large and probably catastrophic mass movement events, leaving behind headwalls that constitute the basal scarp. This evidence stems from the morphology and internal structure of aureole blocks, which exhibit remnants of volcanic flow units on their surfaces. Our claim is supported by plausible reconstructions of the prefailure flanks. Structural analogs to known flank failure events at Hawaiian volcanoes suggest that repeated cycles of flank growth and collapse at Olympus Mons allow generation of the observed aureoles from a protoedifice similar in size and shape to the present one.

  17. Complete mitochondrial genome sequence of Chestnut-flanked white-eye (Zosterops erythropleurus).

    PubMed

    Li, Yumei; Yao, Jiyuan; Zhao, Xin; Li, Lingyu; Yan, Shouqing

    2016-09-01

    The Chestnut-flanked white-eye (Zosterops erythropleurus) is a species of family Zosteropidae, which is distributed widely in the world. In the present study, the complete mitochondrial genome sequence of Chestnut-flanked white-eye was determined. It has a total length of 17 811 bp, and contains 13 protein-coding genes, 22 tRNA genes, 2 ribosome RNA genes and 2 control regions. The total base composition was 30.2% for A, 31.0% for C, 14.2% for G and 24.6% for T. The phylogenetic tree of Chestnut-flanked white-eye and 13 other species belonging to the order Passeriformes was built. The molecular data presented here will be useful to study the evolutionary relationships and genetic diversity of Chestnut-flanked white-eye. PMID:26260179

  18. Rift zone reorganization through flank instability in ocean island volcanoes: an example from Tenerife, Canary Islands

    NASA Astrophysics Data System (ADS)

    Walter, T. R.; Troll, V. R.; Cailleau, B.; Belousov, A.; Schmincke, H.-U.; Amelung, F.; Bogaard, P.

    2005-04-01

    The relationship between rift zones and flank instability in ocean island volcanoes is often inferred but rarely documented. Our field data, aerial image analysis, and 40Ar/39Ar chronology from Anaga basaltic shield volcano on Tenerife, Canary Islands, support a rift zone—flank instability relationship. A single rift zone dominated the early stage of the Anaga edifice (~6-4.5 Ma). Destabilization of the northern sector led to partial seaward collapse at about ~4.5 Ma, resulting in a giant landslide. The remnant highly fractured northern flank is part of the destabilized sector. A curved rift zone developed within and around this unstable sector between 4.5 and 3.5 Ma. Induced by the dilatation of the curved rift, a further rift-arm developed to the south, generating a three-armed rift system. This evolutionary sequence is supported by elastic dislocation models that illustrate how a curved rift zone accelerates flank instability on one side of a rift, and facilitates dike intrusions on the opposite side. Our study demonstrates a feedback relationship between flank instability and intrusive development, a scenario probably common in ocean island volcanoes. We therefore propose that ocean island rift zones represent geologically unsteady structures that migrate and reorganize in response to volcano flank instability.

  19. RADIAL VELOCITY PLANETS DE-ALIASED: A NEW, SHORT PERIOD FOR SUPER-EARTH 55 Cnc e

    SciTech Connect

    Dawson, Rebekah I.; Fabrycky, Daniel C. E-mail: daniel.fabrycky@gmail.co

    2010-10-10

    Radial velocity measurements of stellar reflex motion have revealed many extrasolar planets, but gaps in the observations produce aliases, spurious frequencies that are frequently confused with the planets' orbital frequencies. In the case of Gl 581 d, the distinction between an alias and the true frequency was the distinction between a frozen, dead planet and a planet possibly hospitable to life. To improve the characterization of planetary systems, we describe how aliases originate and present a new approach for distinguishing between orbital frequencies and their aliases. Our approach harnesses features in the spectral window function to compare the amplitude and phase of predicted aliases with peaks present in the data. We apply it to confirm prior alias distinctions for the planets GJ 876 d and HD 75898 b. We find that the true periods of Gl 581 d and HD 73526 b/c remain ambiguous. We revise the periods of HD 156668 b and 55 Cnc e, which were afflicted by daily aliases. For HD 156668 b, the correct period is 1.2699 days and the minimum mass is (3.1 {+-} 0.4) M{sub +}. For 55 Cnc e, the correct period is 0.7365 days-the shortest of any known planet-and the minimum mass is (8.3 {+-} 0.3) M{sub +}. This revision produces a significantly improved five-planet Keplerian fit for 55 Cnc, and a self-consistent dynamical fit describes the data just as well. As radial velocity techniques push to ever-smaller planets, often found in systems of multiple planets, distinguishing true periods from aliases will become increasingly important.

  20. Effect of a gelatin-based edible coating containing cellulose nanocrystals (CNC) on the quality and nutrient retention of fresh strawberries during storage

    NASA Astrophysics Data System (ADS)

    Fakhouri, F. M.; Casari, A. C. A.; Mariano, M.; Yamashita, F.; Innocnentini Mei, L. H.; Soldi, V.; Martelli, S. M.

    2014-08-01

    Strawberry is a non-climacteric fruit with a very short postharvest shelf-life. Loss of quality in this fruit is mostly due to its relatively high metabolic activity and sensitivity to fungal decay, meanly grey mold (Botrytis cinerea). In this study, the ability of gelatin coatings containing cellulose nanocrystals (CNC) to extend the shelf-life of strawberry fruit (Fragaria ananassa) over 8 days were studied. The filmogenic solution was obtained by the hydration of 5 g of gelatin (GEL) in 100 mL of distillated water containing different amounts of CNC dispersion (10 mg CNC/g of GEL or 50 mg of CNC/g of GEL) for 1 hour at room temperature. After this period, the solution was heated to 70 °C and maintained at this temperature for 10 minutes. The plasticizer (glycerol) (10g/100g of the GEL) was then added with constant, gentle stirring in order to avoid forming air bubbles and also to avoid gelatin denaturation until complete homogenization. Strawberries (purchased at the local market) were immersed in the filmogenic solution for 1 minute and after coated were dried at 15 °C by 24 hours. The strawberries were then kept under refrigeration and characterized in terms of their properties (weight loss, ascorbic acid content, titratable acidity, water content). The results have shown that samples covered with GEL/CNC had a significant improvement in its shelf- life. For instance, for the control sample (without coating) the weight loss after 8 days of storage was around 65%, while covered samples loss in the range of 31-36%. Edible coating was also effective in the retention of ascorbic acid (AA) in the strawberries, while control sample presented a fast decay in the AA content, covered samples showed a slow decay in the AA concentration. Moreover, the use of GEL/CNC edible coating had an antimicrobial effect in the fruits.

  1. A similar 5'-flanking region is required for estrogen and progesterone induction of ovalbumin gene expression.

    PubMed

    Dean, D C; Gope, R; Knoll, B J; Riser, M E; O'Malley, B W

    1984-08-25

    We have previously transferred an ovalbumin-beta-globin fusion gene (ovalglobin) into primary cultures of chick oviduct cells and demonstrated that an ovalbumin gene 5'-flanking sequence between -221 and -95 is necessary for progesterone-mediated transcriptional induction (Dean, D. C., Knoll, B. J., Riser, M. E., and O'Malley, B. W. (1983) Nature (Lond.) 305, 551-554). Here we compare 5'-flanking sequences required for induction of the ovalglobin gene by 17 beta-estradiol and progesterone. The early gene of simian virus 40 was inserted into the same plasmid as the ovalbumin fusion gene to serve as an internal control. Since transcription of the viral early gene was unaffected by the presence of steroid hormone or deletions in the ovalbumin gene 5'-flanking region, the level of its transcripts could be monitored as a reference standard for ovalglobin transcription. Ovalglobin transcripts initiated principally from the ovalbumin cap site in the presence or absence of progesterone and 17 beta-estradiol. Deletion of 5'-flanking sequences to -197 had little effect on the induction with either hormone, while successive deletions to -180, -161, and -143 resulted in a gradual decrease in the level of induction. Deletion to -95 eliminated the induction. The results of this study indicate that DNA control elements for regulation of the ovalbumin gene by estrogen and progesterone either overlap directly or are clustered in close proximity in the 5'-flanking region near the ovalbumin gene promoter. PMID:6088508

  2. Structural style of east flank of Bighorn Mountains, Johnson and Sheridan Counties, Wyoming

    SciTech Connect

    Furner, R.B. )

    1989-09-01

    The 70 mi-long portion of the east flank of the Bighorn Mountains, between Sheridan and Mayoworth, Wyoming, is structurally divisible into three distinct segments - northern, central, and southern - each distinguished by a dominant sense of vergence and structural style. The northern segment displays southwest-verging reverse faults and associated folds, indicating tectonic transport out of the Powder River basin and onto the mountain flank. The central segment displays northeast and east-northeast-verging reverse faults and associated folds, indicating tectonic transport of the mountain flank over the Powder River basin. Seismic and drill-hole data indicate most of these reverse faults dip to the southwest and west-southwest at angles of 35{degree} or less. The southern segment displays west-southwest-verging reverse faults and associated folds, again indicating tectonic transport out of the Powder River basin and onto the mountain flank. All major structures identified within the area of investigation are basement involved, and the geometry of the rocks supports the concept that the mountain flank deformed under the influence of northeast-southwest-directed horizontal compression rather than vertically oriented block uplift.

  3. Estimation of tool wear during CNC milling using neural network-based sensor fusion

    NASA Astrophysics Data System (ADS)

    Ghosh, N.; Ravi, Y. B.; Patra, A.; Mukhopadhyay, S.; Paul, S.; Mohanty, A. R.; Chattopadhyay, A. B.

    2007-01-01

    Cutting tool wear degrades the product quality in manufacturing processes. Monitoring tool wear value online is therefore needed to prevent degradation in machining quality. Unfortunately there is no direct way of measuring the tool wear online. Therefore one has to adopt an indirect method wherein the tool wear is estimated from several sensors measuring related process variables. In this work, a neural network-based sensor fusion model has been developed for tool condition monitoring (TCM). Features extracted from a number of machining zone signals, namely cutting forces, spindle vibration, spindle current, and sound pressure level have been fused to estimate the average flank wear of the main cutting edge. Novel strategies such as, signal level segmentation for temporal registration, feature space filtering, outlier removal, and estimation space filtering have been proposed. The proposed approach has been validated by both laboratory and industrial implementations.

  4. Magmatism on rift flanks: Insights from ambient noise phase velocity in Afar region

    NASA Astrophysics Data System (ADS)

    Korostelev, Félicie; Weemstra, Cornelis; Leroy, Sylvie; Boschi, Lapo; Keir, Derek; Ren, Yong; Molinari, Irene; Ahmed, Abdulhakim; Stuart, Graham W.; Rolandone, Frédérique; Khanbari, Khaled; Hammond, James O. S.; Kendall, J. M.; Doubre, Cécile; Ganad, Ismail Al; Goitom, Berhe; Ayele, Atalay

    2015-04-01

    During the breakup of continents in magmatic settings, the extension of the rift valley is commonly assumed to initially occur by border faulting and progressively migrate in space and time toward the spreading axis. Magmatic processes near the rift flanks are commonly ignored. We present phase velocity maps of the crust and uppermost mantle of the conjugate margins of the southern Red Sea (Afar and Yemen) using ambient noise tomography to constrain crustal modification during breakup. Our images show that the low seismic velocities characterize not only the upper crust beneath the axial volcanic systems but also both upper and lower crust beneath the rift flanks where ongoing volcanism and hydrothermal activity occur at the surface. Magmatic modification of the crust beneath rift flanks likely occurs for a protracted period of time during the breakup process and may persist through to early seafloor spreading.

  5. Physical properties of lava flows on the southwest flank of Tyrrhena Patera, Mars

    NASA Technical Reports Server (NTRS)

    Crown, David A.; Porter, Tracy K.; Greeley, Ronald

    1991-01-01

    Tyrrhena Patera (TP) (22 degrees S, 253.5 degrees W), a large, low-relief volcano located in the ancient southern highlands of Mars, is one of four highland paterae thought to be structurally associated with the Hellas basin. The highland paterae are Hesperian in age and among the oldest central vent volcanoes on Mars. The morphology and distribution of units in the eroded shield of TP are consistent with the emplacement of pyroclastic flows. A large flank unit extending from TP to the SW contains well-defined lava flow lobes and leveed channels. This flank unit is the first definitive evidence of effusive volcanic activity associated with the highland paterae and may include the best preserved lava flows observed in the Southern Hemisphere of Mars. Flank flow unit averages, channelized flow, flow thickness, and yield strength estimates are discussed. Analysis suggests the temporal evolution of Martian magmas.

  6. Sequence specific generation of a DNA panhandle permits PCR amplification of unknown flanking DNA.

    PubMed Central

    Jones, D H; Winistorfer, S C

    1992-01-01

    We present a novel method for the PCR amplification of unknown DNA that flanks a known segment directly from human genomic DNA. PCR requires that primer annealing sites be present on each end of the DNA segment that is to be amplified. In this method, known DNA is placed on the uncharacterized side of the sequence of interest via DNA polymerase mediated generation of a PCR template that is shaped like a pan with a handle. Generation of this template permits specific amplification of the unknown sequence. Taq (DNA) polymerase was used to form the original template and to generate the PCR product. 2.2 kb of the beta-globin gene, and 657 bp of the 5' flanking region of the cystic fibrosis transmembrane conductance regulator gene, were amplified directly from human genomic DNA using primers that initially flank only one side of the region amplified. This method will provide a powerful tool for acquiring DNA sequence information. Images PMID:1371352

  7. A Modern Take on the RV Classics: N-body Analysis of GJ 876 and 55 Cnc

    NASA Astrophysics Data System (ADS)

    Nelson, Benjamin E.; Ford, E. B.; Wright, J.

    2013-01-01

    Over the past two decades, radial velocity (RV) observations have uncovered a diverse population of exoplanet systems, in particular a subset of multi-planet systems that exhibit strong dynamical interactions. To extract the model parameters (and uncertainties) accurately from these observations, one requires self-consistent n-body integrations and must explore a high-dimensional 7 x number of planets) parameter space, both of which are computationally challenging. Utilizing the power of modern computing resources, we apply our Radial velocity Using N-body Differential Evolution Markov Chain Monte Carlo code (RUN DEMCMC) to two landmark systems from early exoplanet surveys: GJ 876 and 55 Cnc. For GJ 876, we analyze the Keck HIRES (Rivera et al. 2010) and HARPS (Correia et al. 2010) data and constrain the distribution of the Laplace argument. For 55 Cnc, we investigate the orbital architecture based on a cumulative 1086 RV observations from various sources and transit constraints from Winn et al. 2011. In both cases, we also test for long-term orbital stability.

  8. Remastering the RV Classics: Self-Consistent Dynamical Models for the 55 Cnc and GJ 876 Planetary Systems

    NASA Astrophysics Data System (ADS)

    Nelson, Benjamin E.; Ford, E. B.; Wright, J.; Fischer, D.

    2014-01-01

    Over the past two decades, radial velocity (RV) observations have uncovered a handful of dynamically rich exoplanet systems. In particular, the 55 Cnc and GJ 876 systems have 4+ planets with some of them displaying planet-planet interactions on the observing timescale. In turn, this makes the posterior distributions of these systems oddly shaped and extremely difficult to sample from, especially when employing a Newtonian model. We apply our Radial velocity Using N-body Differential evolution Markov chain Monte Carlo code (RUN DMC; Nelson et al. 2013, submitted) to these two landmark systems. For 55 Cnc, we investigate the orbital architecture based on a cumulative 1418 RV observations from various sources and transit constraints from Winn et al. 2011. We find planets "b" and "c" are apsidally aligned but not in a mean-motion resonance, and the orbital stability of the system is sensitive to the orbital properties of planet "f". For GJ 876, we analyze the Keck HIRES (Rivera et al. 2010) and HARPS (Correia et al. 2010) data to constrain the distribution of the Laplace argument and mutual inclinations amongst planet pairs based on both the RVs and assumption of long-term stability.

  9. Site-Selective Modification of Cellulose Nanocrystals with Isophorone Diisocyanate and Formation of Polyurethane-CNC Composites.

    PubMed

    Girouard, Natalie M; Xu, Shanhong; Schueneman, Gregory T; Shofner, Meisha L; Meredith, J Carson

    2016-01-20

    The unequal reactivity of the two isocyanate groups in an isophorone diisocyante (IPDI) monomer was exploited to yield modified cellulose nanocrystals (CNCs) with both urethane and isocyanate functionality. The chemical functionality of the modified CNCs was verified with ATR-FTIR analysis and elemental analysis. The selectivity for the secondary isocyanate group using dibutyl tin dilaurate (DBTDL) as the reaction catalyst was confirmed with (13)C NMR. The modified CNCs showed improvements in the onset of thermal degradation by 35 °C compared to the unmodified CNCs. Polyurethane composites based on IPDI and a trifunctional polyether alcohol were synthesized using unmodified (um-CNC) and modified CNCs (m-CNC). The degree of nanoparticle dispersion was qualitatively assessed with polarized optical microscopy. It was found that the modification step facilitated superior nanoparticle dispersion compared to the um-CNCs, which resulted in increases in the tensile strength and work of fracture of over 200% compared to the neat matrix without degradation of elongation at break. PMID:26713564

  10. Stabilization of volcanic flanks by dike intrusion: An example from Kilauea

    USGS Publications Warehouse

    Delaney, P.T.; Denlinger, R.P.

    1999-01-01

    Dike propagation and dilation increases the compression of adjacent rocks. On volcanoes, especially oceanic shields, dikes are accordingly thought to be structurally destabilizing. As compression is incremented, volcanic flanks are driven outward or downslope and thus increase their susceptibility to destructive earthquakes and giant landslides. We show, however, that the 2-m-thick dike emplaced along the east rift zone of Kilauea in 1983 actually stabilized that volcano's flank. Specifically, production of flank earthquakes dropped more than twofold after 1983 as maximum downslope motion slowed to 6 cm ?? year-1 from approximately 40 cm ?? year-1 during 1980-1982. As much as 65 cm of deflationary subsidence above Kilauea's summit and upper rift zones accompanied the dike intrusion. According to recent estimates, this deflation corresponds to a reduction in magma-reservoir pressure of approximately 4 MPa, probably about as much as the driving pressure of the 1983 dike. The volume of the dike, approximately 0.10-0.15 km3, is orders of magnitude less than the estimated 200- to 250-km3 volume of Kilauea's reservoir of magma and nearby hot, mushy rock. Thus, deflation of that reservoir reduces the compressional load on the flank over a much larger area than intrusion of the dike adds to it, particularly at the dominant depth of seismicity, 8-9 km. A Coulomb block model for flank motion during intervals between major earthquakes requires the low-angle fault beneath Kilauea's flank to exhibit slip weakening, conducive to earthquake instability. Accordingly, the triggering mechanism of destructive earthquakes, several of which have struck Hawaii during the past 150 years, need not require stresses accumulated by dike intrusions.

  11. Ultraprecision, high stiffness CNC grinding machines for ductile mode grinding of brittle materials

    NASA Astrophysics Data System (ADS)

    McKeown, Patrick A.; Carlisle, Keith; Shore, Paul; Read, R. F.

    1990-10-01

    Under certain controlled conditions it is now possible to machine brittle materials such as glasses and ceramics using single or multi-point diamond tools (grinding), so that material is removed by plastic flow, leaving crack-free surfaces. This process is called 'shear' or 'ductile' mode grinding. It represents a major breakthrough in modern manufacturing engineering since it promises to enable: - complex optical components, both transmission and reflecting to be generated by advanced CNC machines with very little (or even zero) subsequent polishing. - complex shaped components such as turbine blades, nozzle guide vanes, etc. to be finish machined after near net shape forming, to high precision in advanced ceramics such as silicon nitride, without inducing micro-cracking and thus lowering ultimate rupture strength and fatigue life. Ductile mode "damage free" grinding occurs when the volume of materials stressed by each grit of the grinding wheel is small enough to yield rather than exhibit brittle fracture, i.e. cracking. In practice, this means maintaining the undeformed chip thickness to below the ductile-brittle transition value; this varies from material to material but is generally in the order of 0.1 pm or 100 nm, (hence the term "nanogrinding" is sometimes used) . Thus the critical factors for operating successfully in the ductile regime are machine system accuracy and dynamic stiffness between each grit and the workpiece. In detail this means: (i) High precision 'truing' of the diamond grits, together with dressing of the wheel bond to ensure adequate ' openness'; (ii) Design and build of the grinding wheel spindle with very high dynamic stiffness; error motions, radial and axial, must be considerably less than 100 nfl. (iii) Design and build of the workpiece carriage motion system with very high dynamic stiffness; error motions, linear or rotary, must be well within 100 nm. (iv) Smooth, rumble-free, high-stiffness servo-drives controlling the motions

  12. Comparison of flank modification on Ascraeus and Arsia Montes volcanoes, Mars

    NASA Technical Reports Server (NTRS)

    Zimbelman, James R.

    1993-01-01

    Geologic mapping of the Tharsis Montes on Mars is in progress as part of the Mars Geologic Mapping Program of NASA. Mapping of the southern flanks of Ascraeus Mons at 1:500,000 scale was undertaken first followed by detailed mapping of Arsia Mons; mapping of Pavonis Mons will begin later this year. Results indicate that each of the Tharsis volcanoes displays unique variations on the general 'theme' of a martian shield volcano. Here we concentrate on the flank characteristics on Ascraeus Mons and Arsia Mons, the northernmost and southernmost of the Tharsis Montes, as illustrative of the most prominent trends.

  13. Flank pain and acute renal failure after binge drinking: a growing concern?

    PubMed

    Calviño, Jesús; Bravo, Juan; Millán, Beatriz; Gonzalez-Tabares, Lourdes

    2013-01-01

    We describe two cases of acute renal failure (ARF) after heavy alcohol intake. Remarkable features included a few days latency period after binge drinking, acute flank pain resembling pyelonephritis, lack of rhabdomyolysis or liver injury, and concomitant intake of non-steroidal anti-inflammatory drugs (NSAIDs). Renal function improved with conservative treatment, and despite NSAIDs use, hyperkalemia was not clinically significant. Since binge drinking is common in the Western population, early recognition of this syndrome may be helpful when examining a patient with flank pain and ARF of unclear etiology. PMID:23477481

  14. Upwelling of hydrothermal solutions through ridge flank sediments shown by pore water profiles

    SciTech Connect

    Maris, C.R.P.; Bender, M.L.

    1982-05-07

    High calcium ion and low magnesium ion concentrations in sediment pore waters in cores from the Galapagos Mounds Hydrothermal Field on the flank of the Galapagos Spreading Center are believed to be due to a calcium-magnesium exchange reaction between circulating seawater and basement basalt. The nonlinearity of the calcium ions and magnesium ion gradients indicates that these discharging hydrothermal solutions on the ridge flank are upwelling at the rate of about 1 centimeter per year through the pelagic sediments of the Mounds Field and at about 20 centimeters per year through the hydrothermal mounds themselves.

  15. Cloning and heterologous expression of the ftfCNC-2(1) gene from Weissella confusa MBFCNC-2(1) as an extracellular active fructansucrase in Bacillus subtilis.

    PubMed

    Malik, Amarila; Hapsari, Maria Tyas; Ohtsu, Iwao; Ishikawa, Shu; Takagi, Hiroshi

    2015-05-01

    Fructan-exopolysaccharides (fructan-EPS) (inulin and levan) and their oligosaccharides (fructooligosaccharides, FOS) have drawn considerable interest in the food and pharmaceutical industries. EPS-producing lactic acid bacteria have been reported to produce β-fructans (inulin and levan), as well as α-glucans, by the function of sucrase enzymes, i.e., fructansucrase and glucansucrase. A fructansucrase ftfCNC-2(1) gene from Weissella confusa strain MBFCNC-2(1) was previously cloned in Escherichia coli. In this study, we aimed to express the ftf[CNC-2(1)] gene in Bacillus subtilis to obtain the active form of the extracellular recombinant protein FTF[CNC-2(1)]. This cloning was achieved by inserting the gene in-fusion with the signal sequence of the B. subtilis subtilisin E. SDS-polyacrylamide gel electrophoresis analysis and in situ activity assay with Periodic Acid-Schiff staining revealed that the recombinant FTF[CNC-2(1)] was successfully expressed as an extracellular protein from B. subtilis DB403 in its active form, which was confirmed using sucrose and raffinose. PMID:25454699

  16. An open CAM system for dentistry on the basis of China-made 5-axis simultaneous contouring CNC machine tool and industrial CAM software.

    PubMed

    Lu, Li; Liu, Shusheng; Shi, Shenggen; Yang, Jianzhong

    2011-10-01

    China-made 5-axis simultaneous contouring CNC machine tool and domestically developed industrial computer-aided manufacture (CAM) technology were used for full crown fabrication and measurement of crown accuracy, with an attempt to establish an open CAM system for dental processing and to promote the introduction of domestic dental computer-aided design (CAD)/CAM system. Commercially available scanning equipment was used to make a basic digital tooth model after preparation of crown, and CAD software that comes with the scanning device was employed to design the crown by using domestic industrial CAM software to process the crown data in order to generate a solid model for machining purpose, and then China-made 5-axis simultaneous contouring CNC machine tool was used to complete machining of the whole crown and the internal accuracy of the crown internal was measured by using 3D-MicroCT. The results showed that China-made 5-axis simultaneous contouring CNC machine tool in combination with domestic industrial CAM technology can be used for crown making and the crown was well positioned in die. The internal accuracy was successfully measured by using 3D-MicroCT. It is concluded that an open CAM system for dentistry on the basis of China-made 5-axis simultaneous contouring CNC machine tool and domestic industrial CAM software has been established, and development of the system will promote the introduction of domestically-produced dental CAD/CAM system. PMID:22038364

  17. Unified error model based spatial error compensation for four types of CNC machining center: Part I-Singular function based unified error model

    NASA Astrophysics Data System (ADS)

    Fan, Kaiguo; Yang, Jianguo; Yang, Liyan

    2015-08-01

    To unify the error model for four types of CNC machining center, the comprehensive error model of each type of CNC machining center was established using the homogenous transformation matrix (HTM). The internal rules between the HTMs and the kinematic chains were analyzed in this research. The analysis results show that the HTM elements associated with the motion axes which are at the rear of the reference coordinate system are positive value. On the contrary, the HTM elements associated with the motion axes which are at the front of the reference coordinate system are negative value. To express these internal rules, the singular function was introduced to the HTMs. And a unified error model for four types of CNC machining center was established based on the HTM and the singular function. The unified error model includes 18 error elements which are the main factors affecting the machining accuracy of CNC machine tools. The practical results show that the unified error model is not only suitable for vertical machining center but also suitable for horizontal machining center.

  18. 7. INTERIOR LIVING ROOM SHOWING 6LIGHT FRONT DOOR FLANKED BY ...

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

    7. INTERIOR LIVING ROOM SHOWING 6-LIGHT FRONT DOOR FLANKED BY ONE OF TWO 6-LIGHT OVER 1-LIGHT SASH WINDOWS AT PHOTO RIGHT, AND OPEN DOORWAY TO BEDROOM NUMBER ONE (AND BEDROOM NUMBER TWO IN BACKGROUND) AT PHOTO LEFT. VIEW TO NORTH. - Rush Creek Hydroelectric System, Worker Cottage, Rush Creek, June Lake, Mono County, CA

  19. Hazard potential of volcanic flank collapses raised by new megatsunami evidence.

    PubMed

    Ramalho, Ricardo S; Winckler, Gisela; Madeira, José; Helffrich, George R; Hipólito, Ana; Quartau, Rui; Adena, Katherine; Schaefer, Joerg M

    2015-10-01

    Large-scale gravitational flank collapses of steep volcanic islands are hypothetically capable of triggering megatsunamis with highly catastrophic effects. Yet, evidence for the generation and impact of collapse-triggered megatsunamis and their high run-ups remains scarce or is highly controversial. Therefore, doubts remain on whether island flank failures truly generate enough volume flux to trigger giant tsunamis, leading to diverging opinions concerning the real hazard potential of such collapses. We show that one of the most prominent oceanic volcanoes on Earth-Fogo, in the Cape Verde Islands-catastrophically collapsed and triggered a megatsunami with devastating effects ~73,000 years ago. Our deductions are based on the recent discovery and cosmogenic (3)He dating of tsunamigenic deposits found on nearby Santiago Island, which attest to the impact of this giant tsunami and document wave run-up heights exceeding 270 m. The evidence reported here implies that Fogo's flank failure involved at least one fast and voluminous event that led to a giant tsunami, in contrast to what has been suggested before. Our observations therefore further demonstrate that flank collapses may indeed catastrophically happen and are capable of triggering tsunamis of enormous height and energy, adding to their hazard potential. PMID:26601287

  20. Hazard potential of volcanic flank collapses raised by new megatsunami evidence

    PubMed Central

    Ramalho, Ricardo S.; Winckler, Gisela; Madeira, José; Helffrich, George R.; Hipólito, Ana; Quartau, Rui; Adena, Katherine; Schaefer, Joerg M.

    2015-01-01

    Large-scale gravitational flank collapses of steep volcanic islands are hypothetically capable of triggering megatsunamis with highly catastrophic effects. Yet, evidence for the generation and impact of collapse-triggered megatsunamis and their high run-ups remains scarce or is highly controversial. Therefore, doubts remain on whether island flank failures truly generate enough volume flux to trigger giant tsunamis, leading to diverging opinions concerning the real hazard potential of such collapses. We show that one of the most prominent oceanic volcanoes on Earth—Fogo, in the Cape Verde Islands—catastrophically collapsed and triggered a megatsunami with devastating effects ~73,000 years ago. Our deductions are based on the recent discovery and cosmogenic 3He dating of tsunamigenic deposits found on nearby Santiago Island, which attest to the impact of this giant tsunami and document wave run-up heights exceeding 270 m. The evidence reported here implies that Fogo’s flank failure involved at least one fast and voluminous event that led to a giant tsunami, in contrast to what has been suggested before. Our observations therefore further demonstrate that flank collapses may indeed catastrophically happen and are capable of triggering tsunamis of enormous height and energy, adding to their hazard potential. PMID:26601287

  1. Window type: 4x4 multipaned steel window flanked by 1x4 multipaned ...

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

    Window type: 4x4 multipaned steel window flanked by 1x4 multipaned steel, casements. Concrete stoop, entry overhang and pipe rail detail also illustrated. Building 36, facing northwest - Harbor Hills Housing Project, 26607 Western Avenue, Lomita, Los Angeles County, CA

  2. Window type: paired 2x4 multipaned steel windows flanked by 1x4 ...

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

    Window type: paired 2x4 multipaned steel windows flanked by 1x4 multipaned steel casements, breaking building corner. Raised panel door front entry also illustrated. Ground floor detail Building 19, facing north - Harbor Hills Housing Project, 26607 Western Avenue, Lomita, Los Angeles County, CA

  3. Window type: paired 3x2 multipaned steel window flanked by 1x3 ...

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

    Window type: paired 3x2 multipaned steel window flanked by 1x3 multipaned steel casements, breaking building corner. Broad overhanging eave also illustrated. Second story detail. Building 13, facing east - Harbor Hills Housing Project, 26607 Western Avenue, Lomita, Los Angeles County, CA

  4. Magmatism on rift flanks: insights from Ambient-Noise Phase-velocity in Afar region

    NASA Astrophysics Data System (ADS)

    Korostelev, Félicie; Weemstra, Cornelis; Leroy, Sylvie; Boschi, Lapo; Ren, Yong; Ahmed, Abdulhakim; Keir, Derek; Stuart, Graham W.; Rolandone, Frédérique; Khanbari, Khaled; Hammond, James O. S.; Kendall, J. Michael; Doubre, Cécile; Ganad, Ismail Al

    2015-04-01

    During the breakup of continent in the presence of magma, strain is commonly assumed to initially occur by border faulting, and progressively migrate in space and time towards axial magma intrusion. Magmatic processes near the rift flanks are commonly ignored. We present phase-velocity maps of the crust and uppermost mantle of the conjugate margins of the southern Red Sea (Afar and Yemen) using ambient noise tomography to constrain crustal modification during breakup. Our images show that the low seismic velocities characterize not only upper crust beneath the axial volcanic systems, but also both upper and lower crust beneath rift flanks where ongoing volcanism and hydrothermal activity occurs at the surface. The results show that magmatic modification of the crust beneath rift flanks likely occurs for a protracted period of time during the breakup process, and may persist through to early seafloor spreading. Since ongoing flank magmatism during breakup impacts the thermal evolution of the lithosphere, it has implications for the subsidence history of the rift.

  5. Sudden aseismic fault slip on the south flank of Kilauea volcano.

    PubMed

    Cervelli, Peter; Segall, Paul; Johnson, Kaj; Lisowski, Michael; Miklius, Asta

    2002-02-28

    One of the greatest hazards associated with oceanic volcanoes is not volcanic in nature, but lies with the potential for catastrophic flank failure. Such flank failure can result in devastating tsunamis and threaten not only the immediate vicinity, but coastal cities along the entire rim of an ocean basin. Kilauea volcano on the island of Hawaii, USA, is a potential source of such flank failures and has therefore been monitored by a network of continuously recording geodetic instruments, including global positioning system (GPS) receivers, tilt meters and strain meters. Here we report that, in early November 2000, this network recorded transient southeastward displacements, which we interpret as an episode of aseismic fault slip. The duration of the event was about 36 hours, it had an equivalent moment magnitude of 5.7 and a maximum slip velocity of about 6[?]cm per day. Inversion of the GPS data reveals a shallow-dipping thrust fault at a depth of 4.5[?]km that we interpret as the down-dip extension of the Hilina Pali--Holei Pali normal fault system. This demonstrates that continuously recording geodetic networks can detect accelerating slip, potentially leading to warnings of volcanic flank collapse. PMID:11875566

  6. Tsunami deposits at high altitudes on the flanks of volcanic islands

    NASA Astrophysics Data System (ADS)

    Paris, Raphael

    2016-04-01

    It is actually difficult to infer the mechanisms and dynamics of giant mass failures of oceanic shield volcanoes and to evaluate related tsunami hazards. Marine conglomerates and gravels found at unusually high elevations in Hawaii, Cape Verde, Mauritius and Canary Islands are often interpreted as being the result of tsunami waves generated by such massive flank failures. In the first part of this contribution, we document tsunami deposits (marine gravels with pumices) attached to the northwestern slopes of Tenerife, Canary Islands, at altitudes up to 132 m asl. Stratigraphy of the deposits and composition of the pumices allows identifying sources of the successive tsunamis and proposing a new scenario for the Icod flank failure and El Abrigo caldera-forming eruption ca. 170 ka. Then we propose a litterature review of tsunami deposits at high altitudes on the flanks of volcanic islands, and especially oceanic shield volcanoes. These deposits are discussed in terms of texture, structure, composition and particularly the juvenile volcanic material, and implications for better understanding the mechanisms controlling massive flank failures.

  7. Carboniferous tectonic history of the eastern flank of the Ozark dome

    SciTech Connect

    Nelson, W.J. )

    1993-03-01

    Detailed geologic mapping in southwestern Illinois and southeastern Missouri indicates that the eastern flank of the Ozark dome was a low positive area throughout Carboniferous (Mississippian and Pennsylvanian) time. Rock units of this age consistently thin onto the flank of the dome, and are punctuated by numerous disconformities. Effects of shoaling are prominent in Chesterian strata, which change from dominantly subtidal in the proto-Illinois basin to shallow subtidal, intertidal and supratidal on the flank of the dome. Although the dome probably was exposed subaerially for much of Carboniferous time, it contributed little sediment eastward. The exposed rocks were largely carbonates, which weathered by solution. Several long-lived basement structures on the east flank of the Ozarks were active during the Carboniferous. Chief among them were the Lincoln and Waterloo-Dupo anticlines, the Du Quoin monocline, and the Ste. Genevieve fault zone. All are high-angle reverse faults that strike north to northwest, and are overlain by sharp folds in sedimentary cover. Major displacements took place in late Valmeyeran to Atokan time, and addition deformation occurred in Desmoinesian through post-Pennsylvanian time. The compressional deformation probably is a product of the Ouachita orogeny.

  8. Flanking Magnitudes: Dissociation between Numerosity and Numerical Value in a Selective Attention Task

    ERIC Educational Resources Information Center

    Naparstek, Sharon; Safadi, Ziad; Lichtenstein-Vidne, Limor; Henik, Avishai

    2015-01-01

    The current research examined whether peripherally presented numerical information can affect the speed of number processing. In 2 experiments, participants were presented with a target matrix flanked by a distractor matrix and were asked to perform a comparative judgment (i.e., decide whether the target was larger or smaller than the reference…

  9. Autoradiographic localization of tritiated dihydrotestosterone in the flank organ of the albino hamster

    SciTech Connect

    Lucky, A.W.; Eisenfeld, A.J.; Visintin, I.

    1985-02-01

    In the hamster flank organ, the growth of hair and growth of sebaceous glands are androgen-dependent functions. Although dihydrotestosterone (DHT) is known to be a potent stimulator of flank organ growth, there is no information about localization of DHT receptor sites in this organ. The purpose of this study was to use steroid autoradiography to localize DHT receptors in the hamster flank organ. Because steroid hormones are functional when translocated to nuclear receptors, nuclear localization by autoradiography defines receptor sites. In order to be able to visualize autoradiographic grains from radiolabeled androgens around hair follicles, albino hamsters were studied to avoid confusion between the grains and pigment granules which are abundant in the more common Golden Syrian hamster. Mature male hamsters castrated 24 hours earlier were given tritium-labeled dihydrotestosterone ( (/sup 3/H)DHT). Using the technique of thaw-mount steroid autoradiography, 4-micron unfixed frozen sections were mounted in the dark onto emulsion-coated glass slides and allowed to develop for 4-6 months. (/sup 3/H)DHT was found to be concentrated over sebocyte nuclei. The label was present peripherally as well as in differentiating sebocytes. There was no nuclear localization of (/sup 3/H)DHT in animals pretreated with excessive quantities of unlabeled DHT. Steroid metabolites of (/sup 3/H) DHT were assessed by thin-layer chromatography in paired tissue samples. Most of the label remained with DHT. Uptake was inhibited in the flank organ of hamsters pretreated with unlabeled DHT.

  10. Rift flank segmentation, basin initiation and propagation: a neotectonic example from Lake Baikal

    USGS Publications Warehouse

    Agar, S.M.; Klitgord, Kim D.

    1995-01-01

    New surficial data (field, Landsat TM and topography) define morpho-tectonic domains and rift flank segmentation in the Ol'khon region of the Central Baikal rift. Deformation, drainage and depositional patterns indicate a change in the locus of active extension that may relate to a recent (flank graben has propagated southwards along the rift flank and is still actively fragmenting. These surficial data are used to constrain a model for the time-dependent topographic variations during progressive subsidence along a rift flank, involving the transfer of footwall units to hanging-wall domains. Rapid changes in border fault footwall relief in this model are associated with change in the active border fault location with widespread mass-wasting. The model shows that time-dependent histories need to be integrated with flexural uplift models for active normal faults. The active, syn-rift depositional systems of the Ol'khon region provide a valuable analogue for the early evolution of continental margins and the structural controls on syn-rift hydrocarbon sources and reservoirs.

  11. Evidence for hydrothermal Archaea within the basaltic flanks of the East Pacific Rise.

    PubMed

    Ehrhardt, Christopher J; Haymon, Rachel M; Lamontagne, Michael G; Holden, Patricia A

    2007-04-01

    Little is known about the fluids or the microbial communities present within potentially vast hydrothermal reservoirs contained in still-hot volcanic ocean crust beneath the flanks of the mid-ocean ridge. During Alvin dives in 2002, organic material attached to basalt was collected at low, near-ambient temperatures from an abyssal hill fault scarp in 0.5 Ma lithosphere on the western ridge flank of the East Pacific Rise. Mineral analysis by X-ray diffractometry and scanning electron microscopy revealed high-temperature (> 110 degrees C) phases chalcopyrite (Cu(5)FeS(4)) and 1C pyrrhotite (Fe(1-x)S) within the fault scarp materials. A molecular survey of archaeal genes encoding 16S rRNA identified a diverse hyperthermophilic community, including groups within Crenarchaeota, Euryarchaeota, and Korarchaeota. We propose that the sulfide, metals and archaeal communities originated within a basalt-hosted subseafloor hydrothermal habitat beneath the East Pacific Rise ridge flank and were transported to the seafloor during a recent episode of hydrothermal venting from the abyssal hill fault. Additionally, inferred metabolisms from the fault scarp community suggest that an ecologically unique high-temperature archaeal biosphere may thrive beneath the young East Pacific Rise ridge flank and that abyssal hill fault scarps may present new opportunities for sampling for this largely unexplored microbial habitat. PMID:17359262

  12. Oestrogens Downregulate Tissue Factor Pathway Inhibitor through Oestrogen Response Elements in the 5'-Flanking Region.

    PubMed

    Ali, Huda Omar; Stavik, Benedicte; Myklebust, Christiane Filion; Andersen, Elisabeth; Dahm, Anders E A; Iversen, Nina; Sandset, Per Morten; Skretting, Grethe

    2016-01-01

    Oestrogens influence the pathology and development of hormone-sensitive breast cancers. Tissue factor pathway inhibitor (TFPI) has been shown to be associated with breast cancer pathogenesis. Recently, we found TFPI mRNA levels to be significantly reduced by oestrogens in a breast cancer cell line (MCF7), a process mediated through the oestrogen receptor alpha (ERα). The aim of the present study was to investigate the mechanism(s) by which oestrogens may regulate TFPI at the transcriptional level. The TFPI 5'-flanking region contains three oestrogen response element (ERE) half-sites at positions -845, -769 and -50. Constructs containing the wild type or mutated ERE half-sites of the TFPI 5'-flanking region were generated in a luciferase reporter gene vector and transiently co-transfected with an ERα expression vector into HEK293 cells and subsequently treated with oestrogens. We found that luciferase activity was significantly downregulated after oestrogen stimulation in cells transfected with the wild type construct, an effect that was abolished by mutating either ERE half-sites. Electrophoretic mobility shift assay suggested direct and specific interaction of ERα with the ERE half-sites in the TFPI 5'-flanking region. Chromatin immunoprecipitation showed that ERα was recruited to the region -899 to -578 of the TFPI 5'-flanking region in vivo, where the ERE half-sites -845 and -769 are located. Our results indicate that ERα can interact with all three ERE half-sites in the TFPI 5'-flanking region and thus participate in the repression of oestrogen mediated TFPI transcription in breast cancer cells. PMID:26999742

  13. Concurrent Preoperative Presence of Hydronephrosis and Flank Pain Independently Predicts Worse Outcome of Upper Tract Urothelial Carcinoma

    PubMed Central

    Yeh, Hsin-Chih; Jan, Hau-Chern; Wu, Wen-Jeng; Li, Ching-Chia; Li, Wei-Ming; Ke, Hung-Lung; Huang, Shu-Pin; Liu, Chia-Chu; Lee, Yung-Chin; Yang, Sheau-Fang; Liang, Peir-In; Huang, Chun-Nung

    2015-01-01

    Objectives To investigate the impact of preoperative hydronephrosis and flank pain on prognosis of patients with upper tract urothelial carcinoma. Methods In total, 472 patients with upper tract urothelial carcinoma managed by radical nephroureterectomy were included from Kaohsiung Medical University Hospital Healthcare System. Clinicopathological data were collected retrospectively for analysis. The significance of hydronephrosis, especially when combined with flank pain, and other relevant factors on overall and cancer-specific survival were evaluated. Results Of the 472 patients, 292 (62%) had preoperative hydronephrosis and 121 (26%) presented with flank pain. Preoperative hydronephrosis was significantly associated with age, hematuria, flank pain, tumor location, and pathological tumor stage. Concurrent presence of hydronephrosis and flank pain was a significant predictor of non-organ-confined disease (multivariate-adjusted hazard ratio = 2.10, P = 0.025). Kaplan-Meier analysis showed significantly poorer overall and cancer-specific survival in patients with preoperative hydronephrosis (P = 0.005 and P = 0.026, respectively) and in patients with flank pain (P < 0.001 and P = 0.001, respectively) than those without. However, only simultaneous hydronephrosis and flank pain independently predicted adverse outcome (hazard ratio = 1.98, P = 0.016 for overall survival and hazard ratio = 1.87, P = 0.036 for and cancer-specific survival, respectively) in multivariate Cox proportional hazards models. In addition, concurrent presence of hydronephrosis and flank pain was also significantly predictive of worse survival in patient with high grade or muscle-invasive disease. Notably, there was no difference in survival between patients with hydronephrosis but devoid of flank pain and those without hydronephrosis. Conclusion Concurrent preoperative presence of hydronephrosis and flank pain predicted non-organ-confined status of upper tract urothelial carcinoma. When

  14. Flank pain

    MedlinePlus

    ... FF, ed. Ferri's Clinical Advisor 2015. Philadelphia: PA: Elsevier Mosby; 2015:1205-1207. Landry DW, Bazari H. ... eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 114. McQuaid K. Approach to ...

  15. Aquifers in melt-water channels along the southwest flank of the Des Moines Lobe, Lyon County, Minnesota

    USGS Publications Warehouse

    Schneider, Robert; Rodis, Harry G.

    1961-01-01

    The melt-water channels in Lyon County trend southeastward because the flank of the ice sheet was confined by a landmass that sloped to the northeast. Similar buried channels may be present elsewhere along the southwest flank of the Des Moines lobe. If so, they probably can be located by the methods described.

  16. Computer numerical control (CNC) lithography: light-motion synchronized UV-LED lithography for 3D microfabrication

    NASA Astrophysics Data System (ADS)

    Kim, Jungkwun; Yoon, Yong-Kyu; Allen, Mark G.

    2016-03-01

    This paper presents a computer-numerical-controlled ultraviolet light-emitting diode (CNC UV-LED) lithography scheme for three-dimensional (3D) microfabrication. The CNC lithography scheme utilizes sequential multi-angled UV light exposures along with a synchronized switchable UV light source to create arbitrary 3D light traces, which are transferred into the photosensitive resist. The system comprises a switchable, movable UV-LED array as a light source, a motorized tilt-rotational sample holder, and a computer-control unit. System operation is such that the tilt-rotational sample holder moves in a pre-programmed routine, and the UV-LED is illuminated only at desired positions of the sample holder during the desired time period, enabling the formation of complex 3D microstructures. This facilitates easy fabrication of complex 3D structures, which otherwise would have required multiple manual exposure steps as in the previous multidirectional 3D UV lithography approach. Since it is batch processed, processing time is far less than that of the 3D printing approach at the expense of some reduction in the degree of achievable 3D structure complexity. In order to produce uniform light intensity from the arrayed LED light source, the UV-LED array stage has been kept rotating during exposure. UV-LED 3D fabrication capability was demonstrated through a plurality of complex structures such as V-shaped micropillars, micropanels, a micro-‘hi’ structure, a micro-‘cat’s claw,’ a micro-‘horn,’ a micro-‘calla lily,’ a micro-‘cowboy’s hat,’ and a micro-‘table napkin’ array.

  17. Evidence for Pulsed Hydrothermal Venting from Young Abyssal Hills on the EPR Flank Suggests Frequent Seismic Pumping of Ridge Flank Fluid Flow

    NASA Astrophysics Data System (ADS)

    Haymon, R. M.; MacDonald, K. C.; Benjamin, S. B.; Ehrhardt, C. J.

    2004-12-01

    Although measured heat flow suggests that 40-50% of oceanic hydrothermal heat and fluid flux is from young (0.1-5 Ma) abyssal hill terrain on MOR flanks, hydrothermal vents in this setting rarely have been found. On the EPR flanks, seafloor evidence of venting from abyssal hills has been discovered recently at two sites: on ˜0.1 Ma seafloor at 10° 20'N, 103° 33.2'W ("Tevnia Site") and on ˜0.5 Ma seafloor at 9° 27'N, 104° 32.3'W ("Macrobes Site"). Manifestations of venting at these sites include: fault scarp hydrothermal mineralization and macrofauna; fault scarp flocculations containing hyperthermophilic microbes; and hilltop sediment mounds and craters possibly created by fluid "blow-outs." Hydrothermal deposits recovered at the ˜0.1 Ma "Tevnia Site" are fault breccias that record many episodes of brecciation followed by hydrothermal cementation (Benjamin et al., this session). Tubeworm casings, live crabs, and "dandelions" observed at this site indicate that the most recent episode of venting was active during, or shortly before, this site was visited with Alvin in 1994. To create the 200 m-high axis-facing fault scarp at Tevnia Site in 100,000 years, an average uplift rate of at least 2 cm/y is required. Since off-axis earthquakes located on abyssal hill fault scarps typically are

  18. The 5’ flanking region of miR-378 is hypomethylated in acute myeloid leukemia

    PubMed Central

    Zhu, Xiao-Wen; Wen, Xiang-Mei; Zhang, Ying-Ying; Yang, Lei; Guo, Hong; Yang, Jing; Zhang, Ming; Yin, Jia-Yu; Ma, Ji-Chun; Lin, Jiang; Deng, Zhao-Qun; Qian, Jun

    2015-01-01

    Background: Aberrant expression of miR-378 has been observed in various malignancies including acute myeloid leukemia (AML). However, the mechanism regulating of miR-378 expression remains unknown. This study was aimed to investigate miR-378 methylation and to explore its clinical significance in AML. Methods: Methylation status of miR-378 5’-flanking region was investigated by real-time quantitative methylation-specific PCR (RQ-MSP) and bisulfite-sequencing PCR (BSP). The expression of miR-378 was evaluated by real-time quantitative PCR (RQ-PCR). The correlation between expression of miR-378 and 5’-flanking region methylation was analyzed using 5-aza-2’-deoxycytidine (5-aza-dC) treatment. Results: miR-378 5’-flanking region was significantly hypomethylated in AML patients compared to controls (median 0.109 vs. 0.058) (P=0.048). miR-378 expression was correlated with miR-378 5’-flanking region in leukemic cell line treated with 5-aza-dC, but not in AML patients. The level of miR-378 hypomethylation significantly increased in M2 subtype compared to other subtypes. Moreover, patients with t(8;21) harbored the highest level of miR-378 hypomethylation. However, there was no significant difference in overall survival between patients with high and low miR-378 hypomethylation. The association of miR-378 expression with methylation was not observed in AML patients, but miR-378 expression in THP-1 line was increased while methylation status of miR-378 5-flanking region was decreased after 5-aza-dC treatment. Conclusions: Our findings suggest that miR-378 is reactivated by demethylation after 5-aza-dC treatment. 5’-flanking region of miR-378 is hypomethylated in AML especially in those with t(8;21). PMID:26191124

  19. Oceanic phosphorus imbalance: Magnitude of the mid-ocean ridge flank hydrothermal sink

    NASA Astrophysics Data System (ADS)

    Wheat, C. Geoffrey; McManus, James; Mottl, Michael J.; Giambalvo, Emily

    2003-09-01

    We present a new estimate for the crustal phosphorous sink that results from reactions among seawater, basalt, and sediment blanketing low temperature mid-ocean ridge flank hydrothermal systems. New estimates for global hydrothermal power output, sediment thickness, and the dissolved phosphate concentrations in basement formation fluids indicate that fluid flow through ridge flanks removes 2.8 × 1010 mol P yr-1. This value is larger (130%) than the riverine dissolved flux of inorganic phosphate and is as much as 35% of the sedimentary P sink. The concordant seawater flux (2.1 × 1016 kg yr-1) is 65% of the riverine fluid flux and circulates a fluid volume equivalent to the entire ocean in about 70,000 yr. Additional sampling of seafloor springs is required to further constrain the range of calculated phosphate fluxes; nevertheless the modern phosphorus budget is clearly unbalanced with total sinks outpacing sources.

  20. Piggyback tectonics: Long-term growth of Kilauea on the south flank of Mauna Loa

    USGS Publications Warehouse

    Lipman, P.W.; Sisson, T.W.; Coombs, M.L.; Calvert, A.; Kimura, Jun-Ichi

    2006-01-01

    Compositional and age data from offshore pillow lavas and volcaniclastic sediments, along with on-land geologic, seismic, and deformation data, provide broad perspectives on the early growth of Kilauea Volcano and the long-term geometric evolution of its rift zones. Sulfur-rich glass rinds on pillow lavas and volcaniclastic sediments derived from them document early underwater growth of a large compositionally diverse alkalic edifice. The alkalic rocks yield 40Ar/39Ar ages as old as about 275 ka; transitional-composition lavas, which mark beginning of the shield stage while most or all the edifice remained below sea level, probably first erupted after about 150 ka, and tholeiitic lavas of present-day type are probably younger than 100 ka. Breccia clasts from Papau Seamount and along the lower southwest corner of the Hilina bench are derived from subaerial Mauna Loa, requiring that Mauna Loa's flank underlies western parts of Kilauea at shallow depth. The volume of the Kilauea edifice is therefore smaller (???10,000 km3) than previous estimates (15-40,000 km3); lava-thickness accumulation rates appear to have remained nearly constant during edifice growth, as effusion rates increased from ???25 ?? 106 m3/yr at end of the alkalic stage to the present-day tholeiite rate of ???100 ?? 106 m3/yr. Seismic and gravity data show that the deep plumbing system for Kilauea's magma supply extends nearly vertically through the oceanic crust at least to mantle depths of 30-35 km, directly below its present-day caldera. Proximity of Kilauea's caldera to the surface boundary with Mauna Loa and the presence of Mauna Loa rocks at shallow depth beneath the south flank are difficult to reconcile with a submarine origin for early Kilauea alkalic lavas, unless geometric relations between the two volcanoes have changed substantially during growth of the Kilauea shield. Seismic and ground deformation data suggest seaward spreading of the entire south flank of Hawaii Island, independently

  1. Disparity capture by flanking stimuli: a measure for the cooperative mechanism of stereopsis.

    PubMed

    Petrov, Yury

    2002-03-01

    In this work the range and scaling properties of the cooperative (contextual) interaction that was first proposed by Julesz [Foundations of Cyclopean Perception, University of Chicago Press, Chicago, 1971] to address the correspondence problem in stereopsis is measured. To this end the effect that flanking difference of Gaussians (DoG) patches produce on a perception of a target pair of patches is studied. The relative depth configuration of the target pair can switch from the small disparity gradient to a large disparity gradient state as a result of cooperative effects of the flanking stimuli. It is found that the interaction strength falls with distance. Its range varies for different subjects from 2 to 3 DoG patch sizes and scales proportionally to the size of the stimuli. The results suggest that a very localized cooperative interaction is in effect at a broad range of spatial scales. PMID:11927347

  2. The Silent Earthquakes of Kilauea's South Flank and their Ramifications for Catastrophic Failure

    NASA Astrophysics Data System (ADS)

    Cervelli, P. F.

    2004-12-01

    The south flank of Kilauea Volcano is one of the most actively deforming regions on the planet. GPS measurements taken there since the early 1990s show a persistent seaward migration at rates exceeding 5 cm/yr. Large earthquakes occur on Kilauea with alarming frequency. The largest in historical times, a M7.2 event in 1975, caused more than 6 m of seaward displacement in addition to 3.5 m of coastal subsidence. In the last few years, an intermediate form of south flank deformation has been observed. With slip rates of about 10 cm/day, these so-called ``silent earthquake'' are much slower than the nearly instantaneous brittle failure of normal earthquakes, but vastly faster than the creep that carries the south flank relentlessly toward the sea. Kilauea is the latest subaerial volcano in an archipelago of volcanic islands stretching back to the Kamchatka Peninsula. In just the youngest part of this chain, the modern Hawaiian islands, there are more than 70 submarine debris fields, each thought to represent an ancestral flank collapse. If these collapses occurred catastrophically, they almost certainly created tsunami large enough to inundate nearby islands and perhaps long-lived enough to threaten the entire Pacific basin. Evidence for prehistoric inundation on the Hawaiian island consists of anomalously elevated detrital coral deposits, found at several locales and interpreted as the diaspora of passing tsunami. As the youngest and most active of the subaerial Hawaiian volcanoes, it is natural to wonder if Kilauea--in particular the south flank--is the most likely place for future catastrophic collapses. Since the creation of the continuous GPS network on Kilauea in the mid-1990s, as many as four silent earthquakes have been detected. Two of these, occurring in November 2000 and July 2003, have resulted in elastic deformation fields large enough to model. The modeling shows that these events occurred on a shallow ( ˜ 5 km depth) landward dipping fault, possibly

  3. Stability analysis of Western flank of Cumbre Vieja volcano (La Palma) using numerical modelling

    NASA Astrophysics Data System (ADS)

    Bru, Guadalupe; Gonzalez, Pablo J.; Fernandez-Merodo, Jose A.; Fernandez, Jose

    2016-04-01

    La Palma volcanic island is one of the youngest of the Canary archipelago, being a composite volcano formed by three overlapping volcanic centers. There are clear onshore and offshore evidences of past giant landslides that have occurred during its evolution. Currently, the active Cumbre Vieja volcano is in an early development state (Carracedo et al., 2001). The study of flank instability processes aim to assess, among other hazards, catastrophic collapse and potential tsunami generation. Early studies of the potential instability of Cumbre Vieja volcano western flank have focused on the use of sparse geodetic networks (Moss et al. 1999), surface geological mapping techniques (Day et al. 1999) and offshore bathymetry (Urgeles et al. 1999). Recently, a dense GNSS network and satellite radar interferometry results indicate ground motion consistent with deep-seated creeping processes (Prieto et al. 2009, Gonzalez et al. 2010). In this work, we present a geomechanical advanced numerical model that captures the ongoing deformation processes at Cumbre Vieja. We choose the Finite Elements Method (FEM) which is based in continuum mechanics and is the most used for geotechnical applications. FEM has the ability of using arbitrary geometry, heterogeneities, irregular boundaries and different constitutive models representative of the geotechnical units involved. Our main contribution is the introduction of an inverse approach to constrain the geomechanical parameters using satellite radar interferometry displacements. This is the first application of such approach on a large volcano flank study. We suggest that the use of surface displacements and inverse methods to rigorously constrain the geomechanical model parameter space is a powerful tool to understand volcano flank instability. A particular important result of the studied case is the estimation of displaced rock volume, which is a parameter of critical importance for simulations of Cumbre Vieja tsunamigenic hazard

  4. Genomic organization and 5{prime}-flanking DNA sequence of the murine stomatin gene (Epb72)

    SciTech Connect

    Gallagher, P.G.; Turetsky, T.; Mentzer, W.C.

    1996-06-15

    Stomatin is a poorly understood integral membrane protein that is absent from the erythrocyte membranes of many patients with hereditary stomatocytosis. This report describes the cloning of the murine stomatin chromosomal gene, determination of its genomic structure, and characterization of the 5{prime}-flanking genomic DNA sequences. The stomatin gene is encoded by seven exons spread over {approximately}25 kb of genomic DNA. There is no concordance between the exon structure of the stomatin gene and the locations of three domains predicted on the basis of protein structure. Inspection of the 5{prime}-flanking DNA sequences reveals features of a TATA-less housekeeping gene promoter and consensus sequences for a number of potential DNA-binding proteins. 12 refs., 2 figs., 1 tab.

  5. Germ Cell-Specific Excision of loxP-Flanked Transgenes in Rainbow Trout Oncorhynchus mykiss.

    PubMed

    Katayama, Naoto; Kume, Sachi; Hattori-Ihara, Shoko; Sadaie, Sakiko; Hayashi, Makoto; Yoshizaki, Goro

    2016-04-01

    Cre/loxP-mediated DNA excision in germ cell lineages could contribute substantially to the study of germ cell biology in salmonids, which are emerging as a model species in this field. However, a cell type-specific Cre/loxPsystem has not been successfully developed for any salmonid species. Therefore, we examined the feasibility of Cre/loxP-mediated, germ cell-specific gene excision and transgene activation in rainbow trout. Double-transgenic (wTg) progeny were obtained by mating a transgenic male carryingcrewith a transgenic female carrying thehsc-LRLGgene;crewas driven by rainbow troutvasaregulatory regions and thehsc-LRLGgene was made up of the rainbow troutheat-shock-cognate71promoter, theDsRedgene flanked by twoloxPsites, and theEgfpgene. PCR analysis, fluorescence imaging, and histological analysis revealed that excision of theloxP-flanked sequence and activation ofEgfpoccurred only in germ cells of wTg fish. However, progeny tests revealed that the excision efficiency ofloxP-flanked sequence in germ cells was low (≤3.27%). In contrast, the other wTg fish derived from two differentcre-transgenic males frequently excised theloxP-flanked sequence in germ cells (≤89.25%). Thus, we showed for the first time successful germ cell-specific transgene manipulation via the Cre/loxPsystem in rainbow trout. We anticipate that this technology will be suitable for studies of cell function through cell targeting, cell-linage tracing, and generating cell type-specific conditional gene knockouts and separately for developing sterile rainbow trout in aquaculture. PMID:26911430

  6. Evidence of sheared sills related to flank destabilization in a basaltic volcano

    NASA Astrophysics Data System (ADS)

    Berthod, C.; Famin, V.; Bascou, J.; Michon, L.; Ildefonse, B.; Monié, P.

    2016-04-01

    Piton des Neiges basaltic volcano (La Réunion) has been deeply dissected by erosion, exposing large volumes of debris avalanche deposits. To shed light on the factors that led to volcano flank destabilizations, we studied the structure, the crystallographic and magnetic fabrics of the substratum of a debris avalanche unit. This substratum is a complex of > 50 seaward-dipping sills that has been exposed by the avalanche. Structural observations show that the sill plane in contact with the avalanche is one of the latest intrusions in the sill complex. In this uppermost sill, the anisotropy of magnetic susceptibility (AMS) is correlated to the crystallographic preferred orientation of magmatic silicate minerals, allowing us to use AMS as a proxy to infer the magmatic flow. The AMS fabric across the intrusion is strongly asymmetric, which reveals that the contact sill was emplaced with a normal shear displacement of its hanging wall. The shear displacement and the magma flow in the intrusion are both directed toward the NNE, i.e. toward the sea, which is also the direction of the slope and of the debris avalanche runout. Because all the sills in the intrusion complex have a similar dip and dip direction, it is likely that several of them also underwent a cointrusive slip toward the NNE. We conclude that this cointrusive normal slip, repeated over many intrusions of the sill complex, increased the flank instability of the volcano. This incremental instability may have ended up into the observed debris avalanche deposit. At Piton de la Fournaise, the active volcano of La Réunion, sill intrusion and cointrusive flank displacement have been inferred from geophysical studies for the April 2007 eruption. By providing direct evidence of sheared sills, our study substantiates the idea that repeated sill intrusions may eventually trigger flank destabilizations in basaltic volcanoes.

  7. Evidence for a Mega-Tsunami Generated by Giant Flank Collapse of Fogo Volcano, Cape Verde

    NASA Astrophysics Data System (ADS)

    Ramalho, R. S.; Madeira, J.; Helffrich, G. R.; Schaefer, J. M.; Winckler, G.; Quartau, R.; Adena, K.

    2013-12-01

    Mega-tsunamis generated by ocean island flank collapses are expected to be some of the most hazardous forces of nature, yet evidence for their near-source effects and inferred high run-ups so far is scarce or hotly debated. A newly discovered deposit on the northern coast of Santiago Island (Cape Verde), however, documents the magnitude and run-up height associated with this kind of event. Additionally to chaotic conglomerates distributed from sea-level up to 100 m elevation standing on slopes as steep as 20°, the deposit comprises a number of scattered megaclasts of submarine lava flows, limestone and tuff. The megaclasts are presently located over a higher substructural slope built on younger subaerial lava flows and at elevations ranging 160-220 m a.s.l. All megaclasts correspond to lithologies that crop out exclusively in nearby cliff faces. The origin of this deposit is consequently attributed to an exceptional wave that plucked blocks from the cliff face, transported them inland and deposited them over the higher slopes of the volcanic edifice. The distribution of the megaclasts, together with the local geomorphology, is in agreement with a tsunami that approached the island edifice from the west and was refracted along its northern flank, flooding a series of northwest-oriented valleys. This suggests that the well-known flank collapse of Fogo volcano, located 55 km west of Santiago, is the most likely source, a hypothesis being tested with surface exposure dating. The inferred run-up exceeded 200 m and is consistent with numerical simulations by Paris et al. 2011, implying that the present Fogo island morphology probably developed by at least one giant flank collapse with devastating near-source effects.

  8. A 75-year old man complaining of flank pain and obstructive urinary symptoms: a case report.

    PubMed

    Mohseni, Mohammad-Ghasem; Hamidi, Morteza; Salavati, Alborz; Rangzan, Nazir; Kowsari, Farid

    2011-01-01

    Benign renal cystic adenoma with out malignant features is a very rare entity. A 75 year old male with obstructive Lower tract symptoms and vague flank pain was admitted and planned for nephrectomy of non functional kidney -due to long term nephrolithiasis- intra operative finding was a cystic hydronephrotic kidney filled by thick mucous secretions which turned out to be a cyst adenoma of kidney with no malignant features. PMID:21960085

  9. Rejuvenation of the Kuqa foreland basin, northern flank of the Tarim basin, northwest China

    SciTech Connect

    Lu Huafu; Jia Dong; Cai Dongsheng

    1994-12-01

    The Kuqa depression along the northern flank of the Tarim basin is filled with a thick sequence of Neogene and Quaternary coarse elastic continental sediments. This structural depression is part of a large foreland basin that leads south of the Tianshan - an orogenic belt of intracontinental convergence resulting from the northward propagation of stress following the collision of India with the southern margin of Eurasia. 11 refs., 6 figs., 1 tab.

  10. Hazard Potential of Volcanic Flank Collapses Raised by New Megatsunami Evidence

    NASA Astrophysics Data System (ADS)

    Ramalho, R. S.; Winckler, G.; Madeira, J.; Helffrich, G. R.; Hipólito, A.; Quartau, R.; Adena, K.; Schaefer, J. M.

    2015-12-01

    Large-scale gravitational flank collapses of steep volcanic islands are hypothetically capable of triggering megatsunamis with highly catastrophic effects. Yet evidence for the existence and impact of collapsed-triggered megatsunamis and their run-up heights remains scarce and/or is highly contentious. Therefore a considerable debate still exists over the potential magnitude of collapse-triggered tsunamis and their inherent hazard. In particular, doubts still remain whether or not large-scale flank failures typically generate enough volume flux to result in megatsunamis, or alternatively operate by slow-moving or multiple smaller episodic failures with much lower tsunamigenic potential. Here we show that one of the tallest and most active oceanic volcanoes on Earth - Fogo, in the Cape Verde Islands - collapsed catastrophically and triggered a megatsunami with devastating near-field effects ~73,000 years ago. Our deductions are based on the recent discovery and cosmogenic 3He dating of tsunamigenic deposits - comprising fields of stranded megaclasts, chaotic conglomerates, and sand sheets - found on the adjacent Santiago Island, which attest to the impact of this megatsunami and document wave run-up heights exceeding 270 m. The evidence reported here implies that Fogo's flank failure involved at least one sudden and voluminous event that resulted in a megatsunami, in contrast to what has been suggested before. Our work thus provides another line of evidence that large-scale flank failures at steep volcanic islands may indeed happen catastrophically and are capable of triggering tsunamis of enormous height and energy. This new line of evidence therefore reinforces the hazard potential of volcanic island collapses and stands as a warning that such hazard should not be underestimated, particularly in areas where volcanic island edifices are close to other islands or to highly populated continental margins.

  11. Microbial Life in Ridge Flank Crustal Fluids at Baby Bare Seamount, Juan de Fuca Ridge

    NASA Astrophysics Data System (ADS)

    Huber, J. A.; Johnson, H. P.; Butterfield, D. A.; Baross, J. A.

    2005-12-01

    To determine the microbial community diversity within old oceanic crust, a novel sampling strategy was used to collect crustal fluids at Baby Bare Seamount, a 3.5 Ma old outcrop located in the northeast Pacific Ocean on the eastern flank of the Juan de Fuca Ridge. Stainless steel probes were driven directly into the igneous ocean crust to obtain samples of ridge flank crustal fluids. Genetic signatures and enrichment cultures of microorganisms demonstrate that these crustal fluids host a microbial community composed of species indigenous to the subseafloor, including anaerobic thermophiles, and species from other deep-sea habitats, such as seawater and sediments. Evidence using molecular techniques indicates the presence of a relatively small but active microbial population, dominated by bacteria. The microbial community diversity found in the crustal fluids may indicate habitat variability in old oceanic crust, with inputs of nutrients from seawater, sediment pore-water fluids and possibly hydrothermal sources. This report further supports the presence of an indigenous microbial community in ridge flank crustal fluids and advances our understanding of the potential physiological and phylogenetic diversity of this community.

  12. Condensin promotes the juxtaposition of DNA flanking its loading site in Bacillus subtilis

    PubMed Central

    Wang, Xindan; Le, Tung B.K.; Lajoie, Bryan R.; Dekker, Job; Laub, Michael T.; Rudner, David Z.

    2015-01-01

    SMC condensin complexes play a central role in compacting and resolving replicated chromosomes in virtually all organisms, yet how they accomplish this remains elusive. In Bacillus subtilis, condensin is loaded at centromeric parS sites, where it encircles DNA and individualizes newly replicated origins. Using chromosome conformation capture and cytological assays, we show that condensin recruitment to origin-proximal parS sites is required for the juxtaposition of the two chromosome arms. Recruitment to ectopic parS sites promotes alignment of large tracks of DNA flanking these sites. Importantly, insertion of parS sites on opposing arms indicates that these “zip-up” interactions only occur between adjacent DNA segments. Collectively, our data suggest that condensin resolves replicated origins by promoting the juxtaposition of DNA flanking parS sites, drawing sister origins in on themselves and away from each other. These results are consistent with a model in which condensin encircles the DNA flanking its loading site and then slides down, tethering the two arms together. Lengthwise condensation via loop extrusion could provide a generalizable mechanism by which condensin complexes act dynamically to individualize origins in B. subtilis and, when loaded along eukaryotic chromosomes, resolve them during mitosis. PMID:26253537

  13. Flanking A·T Basepairs Destabilize the B∗ Conformation of DNA A-Tracts

    PubMed Central

    Stellwagen, Earle; Dong, Qian; Stellwagen, Nancy C.

    2015-01-01

    Capillary electrophoresis has been used to characterize the interaction of monovalent cations with 26-basepair DNA oligomers containing A-tracts embedded in flanking sequences with different basepair compositions. A 26-basepair random-sequence oligomer was used as the reference; lithium and tetrabutylammonium (TBA+) ions were used as the probe ions. The free solution mobilities of the A-tract and random-sequence oligomers were identical in solutions containing <∼100 mM cation. At higher cation concentrations, the A-tract oligomers migrated faster than the reference oligomer in TBA+ and slower than the reference in Li+. Hence, cations of different sizes can interact very differently with DNA A-tracts. The increased mobilities observed in TBA+ suggest that the large hydrophobic TBA+ ions are preferentially excluded from the vicinity of the A-tract minor groove, increasing the effective net charge of the A-tract oligomers and increasing the mobility. By contrast, Li+ ions decrease the mobility of A-tract oligomers because of the preferential localization of Li+ ions in the narrow A-tract minor groove. Embedding the A-tracts in AT-rich flanking sequences markedly alters preferential interactions of monovalent cations with the B∗ conformation. Hence, A-tracts embedded in genomic DNA may or may not interact preferentially with monovalent cations, depending on the relative number of A·T basepairs in the flanking sequences. PMID:25954886

  14. Cloning and characterization of the 5'-flanking region of the Ehox gene

    SciTech Connect

    Lee, Woon Kyu . E-mail: wklee@yumc.yonsei.ac.kr; Kim, Yong-Man; Malik, Nasir; Ma Chang; Westphal, Heiner

    2006-03-03

    The paired-like homeobox-containing gene Ehox plays a role in embryonic stem cell differentiation and is highly expressed in the developing placenta and thymus. To understand the mechanisms of regulation of Ehox gene expression, the 5'-flanking region of the Ehox gene was isolated from a mouse BAC library. 5'-RACE analysis revealed a single transcriptional start site 130 nucleotides upstream of the translation initiation codon. Transient transfection with a luciferase reporter gene under the control of serially deleted 5'-flanking sequences revealed that the nt -84 to -68 region contained a positive cis-acting element for efficient expression of the Ehox gene. Mutational analysis of this region and oligonucleotide competition in the electrophoretic mobility shift assay revealed the presence of a CCAAT box, which is a target for transcription nuclear factor Y (NFY). NFY is essential for positive gene regulation. No tissue-specific enhancer was identified in the 1.9-kb 5'-flanking region of the Ehox gene. Ehox is expressed during the early stages of embryo development, specifically in Brain at 9.5 dpc, as well as during the late stages of embryo development. These results suggest that NFY is an essential regulatory factor for Ehox transcriptional activity, which is important for the post-implantation stage of the developing embryo.

  15. Characterization of the 5'-flanking region for the human fibrinogen beta gene.

    PubMed Central

    Huber, P; Dalmon, J; Courtois, G; Laurent, M; Assouline, Z; Marguerie, G

    1987-01-01

    To identify the possible regulatory sequences in the genetic expression of fibrinogen, a human genomic DNA library raised in lambda EMBL 4 phage was screened using cDNA probes coding for the A alpha, B beta and gamma chains of human fibrinogen. The entire fibrinogen locus was characterized and its organization analysed by means of hybridization and restriction mapping. Among the clones identified, a single recombinant lambda phage contained the beta gene and its 5'- and 3'-flanking regions. A 1.5 kb fragment of the immediate 5'-flanking region was sequenced and S1 mapping experiments revealed three transcription start points. Comparison of this sequence with that previously reported for the same region upstream from the human gamma gene revealed no significant homology which suggests that the potential promoting sequences of these genes are different. In contrast, comparison of the 5'-flanking regions of human and rat beta genes revealed a 142 bp sequence of 80% homology situated 16 bp upstream from the human beta gene. This highly conserved region may well represents a potential candidate for a regulatory sequence of the human beta gene. Images PMID:3029722

  16. Analysis of the regions flanking the human insulin gene and sequence of an Alu family member.

    PubMed Central

    Bell, G I; Pictet, R; Rutter, W J

    1980-01-01

    The regions around the human insulin gene have been studied by heteroduplex, hybridization and sequence analysis. These studies indicated that there is a region of heterogeneous length located approximately 700 bp before the 5' end of the gene; and that the 19 kb of cloned DNA which includes the 1430 bp insulin gene as well as 5650 bp before and 11,500 bp after the gene is single copy sequence except for 500 bp located 6000 bp from the 3' end of the gene. This 500 bp segment contains a member of the Alu family of dispersed middle repetitive sequences as well as another less highly repeated homopolymeric segment. The sequence of this region was determined. This Alu repeat is bordered by 19 bp direct repeats and also contains an 83 bp sequence which is present twice. The regions flanking the human and rat I insulin genes were compared by heteroduplex analysis to localize homologous sequences in the flanking regions which could be involved in the regulation of insulin biosynthesis. The homology between the two genes is restricted to the region encoding preproinsulin and a short region of approximately 60 bp flanking the 5' side of the genes. Images PMID:6253909

  17. Condensin promotes the juxtaposition of DNA flanking its loading site in Bacillus subtilis.

    PubMed

    Wang, Xindan; Le, Tung B K; Lajoie, Bryan R; Dekker, Job; Laub, Michael T; Rudner, David Z

    2015-08-01

    SMC condensin complexes play a central role in compacting and resolving replicated chromosomes in virtually all organisms, yet how they accomplish this remains elusive. In Bacillus subtilis, condensin is loaded at centromeric parS sites, where it encircles DNA and individualizes newly replicated origins. Using chromosome conformation capture and cytological assays, we show that condensin recruitment to origin-proximal parS sites is required for the juxtaposition of the two chromosome arms. Recruitment to ectopic parS sites promotes alignment of large tracks of DNA flanking these sites. Importantly, insertion of parS sites on opposing arms indicates that these "zip-up" interactions only occur between adjacent DNA segments. Collectively, our data suggest that condensin resolves replicated origins by promoting the juxtaposition of DNA flanking parS sites, drawing sister origins in on themselves and away from each other. These results are consistent with a model in which condensin encircles the DNA flanking its loading site and then slides down, tethering the two arms together. Lengthwise condensation via loop extrusion could provide a generalizable mechanism by which condensin complexes act dynamically to individualize origins in B. subtilis and, when loaded along eukaryotic chromosomes, resolve them during mitosis. PMID:26253537

  18. Active uplift and normal faulting in the eastern flank of Taiwan Central Range

    NASA Astrophysics Data System (ADS)

    Chang, Chung-Pai; Hsu, Yi-Chun; Kang, Chu-Chun

    2015-04-01

    As the backbone range of Taiwan orogen, the highest peaks of the Central Range have been uplifted to nearly 4 km above sea level. A rapid exhumation rate of about 6 mm/yr over the past several million years has been determined by many previous thermochronological studies in the eastern flank of the Central Range. However, the uplift mechanism of the Central Range is still in debate. Especially, the most important structural component, the Central Range Fault in the eastern boundary of the Central Range, has never been clearly observed in the previous studies. An east-vergent "backthrusting" or "backfolding" was firstly proposed by Ernst in 1977. However, normal faulting and oblique faulting with a normal component were also proposed by the following field workers (e.g., Crespi et al., 1996; Fisher, 1999). In this study, we use the geomorphic, stratigraphic, and structural analyses to figure out the near surface geometry of the Central Range Fault, and as well use the recent earthquake data to understand the deeper structures beneath the Central Range. By combining these results, we propose a doubly vergent model with a roll-back Central Range fault to explain the local structure and the rapid uplift of the eastern flank of the Central Range. The normal faults along the eastern flank of Central Range can also be separated into three segments form the north to the south. This late-stage structure suggests that the rotation-accommodating structure is extensional in nature.

  19. Mechanical response of the south flank of kilauea volcano, hawaii, to intrusive events along the rift systems

    USGS Publications Warehouse

    Dvorak, J.J.; Okamura, A.T.; English, T.T.; Koyanagi, R.Y.; Nakata, J.S.; Sako, M.K.; Tanigawa, W.T.; Yamashita, K.M.

    1986-01-01

    Increased earthquake activity and compression of the south flank of Kilauea volcano, Hawaii, have been recognized by previous investigators to accompany rift intrusions. We further detail the temporal and spatial changes in earthquake rates and ground strain along the south flank induced by six major rift intrusions which occurred between December 1971 and January 1981. The seismic response of the south flank to individual rift intrusions is immediate; the increased rate of earthquake activity lasts from 1 to 4 weeks. Horizontal strain measurements indicate that compression of the south flank usually accompanies rift intrusions and eruptions. Emplacement of an intrusion at a depth greater than about 4 km, such as the June 1982 southwest rift intrusion, however, results in a slight extension of the subaerial portion of the south flank. Horizontal strain measurements along the south flank are used to locate the January 1983 east-rift intrusion, which resulted in eruptive activity. The intrusion is modeled as a vertical rectangular sheet with constant displacement perpendicular to the plane of the sheet. This model suggests that the intrusive body that compressed the south flank in January 1983 extended from the surface to about 2.4 km depth, and was aligned along a strike of N66??E. The intrusion is approximately 11 km in length, extended beyond the January 1983 eruptive fissures, which are 8 km in length and is contained within the 14-km-long region of shallow rift earthquakes. ?? 1986.

  20. Evolution of the north flank of Tenerife by recurrent giant landslides

    NASA Astrophysics Data System (ADS)

    Ablay, G.; Hürlimann, M.

    2000-12-01

    Geomorphologic analysis of submarine and subaerial surface features using a combined topographic/bathymetric digital elevation model coupled with onshore geological and geophysical data constrain the age and geometry of giant landslides affecting the north flank of Tenerife. Shaded relief and contour maps, and topographic profiles of the submarine north flank, permit the identification of two generations of post-shield landslides. Older landslide materials accumulated near the shore (<40-km) and comprise ˜700 km 3 of debris. Thickening towards a prominent axis suggests one major landslide deposit. Younger landslide materials accumulated 40-70 km offshore and comprise the products of three major landslides: the La Orotava landslide complex, the Icod landslide and the East Dorsal landslide complex, each with an onshore scar, a proximal submarine trough, and a distal deposit lobe. Estimated lobe volumes are 80, 80 and 100 km 3, respectively. The old post-shield landslide scar is an amphitheatre, 20-25 km wide, partly submarine, now completely filled with younger materials. Age-width relationships for Tenerife's coastal platform plus onshore geological constraints suggest an age of ca. 3 Ma for the old collapse. Young landslides are all less than 560 ka old. The La Orotava and Icod slides involved failures of slabs of subaerial flank to form the subaerial La Orotava and Icod valleys. Offshore, they excavated troughs by sudden loading and basal erosion of older slide debris. The onshore East Dorsal slide also triggered secondary failure of older debris offshore. The slab-like geometry of young failures was controlled by weak layers, deep drainage channels and flank truncation by marine erosion. The (partly) submarine geometry of the older amphitheatre reflects the absence of these features. Relatively low H/ L ratios for the young slides are attributed to filling of the slope break at the base of the submarine edifice by old landslide materials, low aspect ratios of

  1. Analyses of Etna Eruptive Activity From 18th Century and Characterization of Flank Eruptions

    NASA Astrophysics Data System (ADS)

    del Carlo, P.; Branca, S.; Coltelli, M.

    2003-12-01

    Etna explosive activity has usually been considered subordinate with respect to the effusive eruptions. Nevertheless, in the last decade and overall after the 2001 and 2002 flank eruptions, explosive activity has drawn the attention of the scientific and politic communities owing to the damages that the long-lasting ash fall caused to Sicily's economy. We analyzed the eruptions from the 18th century to find some analogous behavior of Etna in the past. A study of the Etna historical record (Branca and Del Carlo, 2003) evidenced that after the 1727 eruption, there are no more errors in the attribution of the year of the eruption. Furthermore from this time on, the scientific quality of the chronicles allowed us to obtain volcanological information and to estimate the magnitude of the major explosive events. The main goal of this work was to characterize the different typologies of Etna eruptions in the last three centuries. Meanwhile, we have tried to find the possible relationship between the two kinds of activity (explosive and effusive) in order to understand the complexity of the eruptive phenomena and define the short-term behavior of Etna. On the base of the predominance of the eruptive typology (effusive or explosive) we have classified the flank eruptions in three classes: i) Type 1: almost purely effusive; ii) Type 2: the intensity of explosive activity comparable with the effusive; iii) Type 3: almost purely explosive with minor lava effusion (only the 1763 La Montagnola and 2002 eruptions belong to this class). Long-lasting explosive activity is produced by flank eruptions with continuous ash emission and prolonged fallout on the flanks (e.g. 1763, 1811, 1852-53, 1886, 1892, 2001 and 2002 eruptions). At summit craters continuous activity is weaker, whereas the strongest explosive eruptions are short-lived events. Furthermore, from the 18th to 20th century there were several years of intense and discontinuous summit explosive activity, from high strombolian

  2. Unified error model based spatial error compensation for four types of CNC machining center: Part II-unified model based spatial error compensation

    NASA Astrophysics Data System (ADS)

    Fan, Kaiguo; Yang, Jianguo; Yang, Liyan

    2014-12-01

    In this paper, a spatial error compensation method was proposed for CNC machining center based on the unified error model. The spatial error distribution was analyzed in this research. The result shows that the spatial error is relative to each axis of a CNC machine tool. Moreover, the spatial error distribution is non-linear and there is no regularity. In order to improve the modeling accuracy and efficiency, an automatic error modeling application was designed based on the orthogonal polynomials. To realize the spatial error compensation, a multi-thread parallel processing mode based error compensation controller was designed. Using the spatial error compensation method, the machine tools' accuracy is greatly improved compared to that with no compensation.

  3. Possible selective formation of CNC/sup +/ and CCN/sup +/ in the interstellar reactions of C/sup +/ with HCN and HNC/sup +/

    SciTech Connect

    Haese, N.N.; Woods, R.C.

    1981-05-15

    The molecular structures of CNC/sup +/ and CCN/sup +/ have been determined by double zeta self-consistent field (SCF) calculations. Their standard heats of formation are theoretically estimated to be 372 +- 20 and 421 +- 25 kcal mol/sup -1/, respectively, the latter determined by double zeta plus polarization SCF-CI (configuration interaction) calculation of the isomerization energy for CNC/sup +/..-->..CCN/sup +/. Using these results, the available appearance potential data for these ions in the mass spectra of HC/sub 3/N and C/sub 2/N/sub 2/ can be explained by simple reactions, and the numerical agreement between the corresponding experimental and theoretical heats of formation is excellent. With this thermochemical information and mechanistic considerations of C/sup +/ reactions with HCN and HNC, we propose that CNC/sup +/ may be selectively made from HCN, and CCN/sup +/ from HNC, and that this selectivity may play an important role in the chemistry of the interstellar medium. For the polar isomer CCN/sup +/ we report an SCF prediction of its rotational constant (11.93 +- 0.5 GHz) and a higher-level (CI) calculation of its electric dipole moment (2.50 +- 0.2 debye) and nitrogen nuclear quadrupole coupling constant (-4.95 +- 0.5 MHz).

  4. Luminescent organoplatinum(II) complexes with functionalized cyclometalated C^N^C ligands: structures, photophysical properties, and material applications.

    PubMed

    Kui, Steven C F; Hung, Faan-Fung; Lai, Shiu-Lun; Yuen, Mai-Yan; Kwok, Chi-Chung; Low, Kam-Hung; Chui, Stephen Sin-Yin; Che, Chi-Ming

    2012-01-01

    A series of [(R'-C^N^C-R'')Pt(L)] complexes with doubly deprotonated cyclometalated R'-C^N^C-R'' ligands (R'-C^N^C-R''=2,6-diphenylpyridine derivatives) functionalized with carbazole, fluorene, or thiophene unit(s) have been synthesized and their photophysical properties studied. The X-ray crystal structures reveal extensive intermolecular π···π and C-H···π interactions between the cyclometalated C^N^C ligands. Compared to previously reported cyclometalated platinum(II) complexes [(C^N^C)Pt(L)], which are non-emissive in solution at room temperature, the carbazole-, fluorene- and thiophene-functionalized [(R'-C^N^C-R'')Pt(L)] (L=DMSO 1-9, C≡N-Ar, 1a-9a) complexes are emissive in solution at room temperature with λ(max) at 564-619 nm and Φ=0.02-0.26. The emissions of the [(R'-C^N^C-R'')Pt(L)] complexes are attributed to electronic excited states with mixed (3)MLCT and (3)IL character. The carbazole/fluorene/thiophene unit(s) allow the tuning of the electronic properties of the [(R'-C^N^C-R'')Pt] moiety, with the emission maxima in a range of 564-619 nm. These are the first examples of organoplatinum(II) complexes bearing doubly deprotonated cyclometalated C^N^C ligands that are emissive in solution at room temperature. In non-degassed DMSO, the emission intensities of 6a-9a are enhanced upon exposure to ambient light. This phenomenon is caused by reacting photogenerated (1)O(2) with a DMSO molecule to form dimethyl sulfone, leading to the removal of dissolved oxygen in solution. Self-assembled nanowires and nanorods are obtained from precipitation of 3a in THF/H(2)O and 8a in DMSO/Et(2)O, respectively. The [(R'-C^N^C-R'')Pt(L)] complexes are soluble in common organic solvents with a high thermal stability (>300 °C), rendering them as phosphorescent dopants for organic light-emitting diode (OLEDs) applications. Red OLEDs with CIE coordinates of (0.65±0.01, 0.35±0.01) were fabricated from 7a or 8a. A maximum external efficiency (η(Ext)) of 12.6% was

  5. Polyglutamine domain flexibility mediates the proximity between flanking sequences in huntingtin

    PubMed Central

    Caron, Nicholas Stephane; Desmond, Carly Robyn; Xia, Jianrun; Truant, Ray

    2013-01-01

    Huntington disease (HD) is a neurodegenerative disorder caused by a CAG expansion within the huntingtin gene that encodes a polymorphic glutamine tract at the amino terminus of the huntingtin protein. HD is one of nine polyglutamine expansion diseases. The clinical threshold of polyglutamine expansion for HD is near 37 repeats, but the mechanism of this pathogenic length is poorly understood. Using Förster resonance energy transfer, we describe an intramolecular proximity between the N17 domain and the downstream polyproline region that flanks the polyglutamine tract of huntingtin. Our data support the hypothesis that the polyglutamine tract can act as a flexible domain, allowing the flanking domains to come into close spatial proximity. This flexibility is impaired with expanded polyglutamine tracts, and we can detect changes in huntingtin conformation at the pathogenic threshold for HD. Altering the structure of N17, either via phosphomimicry or with small molecules, also affects the proximity between the flanking domains. The structural capacity of N17 to fold back toward distal regions within huntingtin requires an interacting protein, protein kinase C and casein kinase 2 substrate in neurons 1 (PACSIN1). This protein has the ability to bind both N17 and the polyproline region, stabilizing the interaction between these two domains. We also developed an antibody-based FRET assay that can detect conformational changes within endogenous huntingtin in wild-type versus HD fibroblasts. Therefore, we hypothesize that wild-type length polyglutamine tracts within huntingtin can form a flexible domain that is essential for proper functional intramolecular proximity, conformations, and dynamics. PMID:23898200

  6. Peering Beneath the Transantarctic Mountains Rift Flank with New Gravity Data

    NASA Astrophysics Data System (ADS)

    Anderson, L.; Ferraccioli, F.; Jordan, T. A.; Watts, A. B.; Armadillo, E.; Bozzo, E.

    2010-12-01

    The West Antarctic Rift System (WARS) is one of the largest and most poorly understood continental rift systems. It is flanked by the Transantarctic Mountains (TAM), which extend for over 3,000 km from the Ross Sea Rift (RSR) to the Weddell Sea. Compared to other rift flanks the range is significantly higher, longer and wider. Unravelling the tectonic, climate and ice sheet processes, which may be responsible for these unique characteristics, requires an improved knowledge of its deeper crustal architecture and uplift mechanisms. Limited wide-angle and passive seismic data have provided some insight into the boundary between East and West Antarctica, but uplift mechanisms for the TAM remain controversial. TAM uplift has been linked to Cretaceous distributed extension in the WARS, Cenozoic flexure along its flank, and erosional denudation related to glacial incision at the margin of the East Antarctic Ice Sheet, or pre-glacial fluvial incision. The most recent hypothesis is that the TAM form the edge of an elevated plateau, which collapsed in response to distributed Cretaceous extension in the WARS. Here we present new models for the crustal structure and uplift mechanisms for the TAM, based on a compilation of aerogravity and land gravity data over the Prince Albert Block (PAB) and marine gravity in the RSR. We incorporated independent wide-angle and passive seismic constraints onshore and existing seismic reflection interpretations across the Victoria Land Basin within the RSR. Our preferred model indicates that the crust beneath the PAB is 40±2 km thick. A 5 Km-thick root is imaged, in good agreement with previous interpretations further south over the TAM. We propose that a significant component of the root (ca. 3 km) is due to magmatic underplating. Flexural models show that magmatic underplating could drive up to 1/3 of TAM uplift. The remainder is modelled as a function of mechanical unloading, erosion, and thermal buoyancy.

  7. Long-period seismic events with strikingly regular temporal patterns on Katla volcano's south flank (Iceland)

    NASA Astrophysics Data System (ADS)

    Sgattoni, Giulia; Jeddi, Zeinab; Gudmundsson, Ólafur; Einarsson, Páll; Tryggvason, Ari; Lund, Björn; Lucchi, Federico

    2016-09-01

    Katla is a threatening volcano in Iceland, partly covered by the Mýrdalsjökull ice cap. The volcano has a large caldera with several active geothermal areas. A peculiar cluster of long-period seismic events started on Katla's south flank in July 2011, during an unrest episode in the caldera that culminated in a glacier outburst. The seismic events were tightly clustered at shallow depth in the Gvendarfell area, 4 km south of the caldera, under a small glacier stream at the southern margin of Mýrdalsjökull. No seismic events were known to have occurred in this area before. The most striking feature of this seismic cluster is its temporal pattern, characterized by regular intervals between repeating seismic events, modulated by a seasonal variation. Remarkable is also the stability of both the time and waveform features over a long time period, around 3.5 years. We have not found any comparable examples in the literature. Both volcanic and glacial processes can produce similar waveforms and therefore have to be considered as potential seismic sources. Discerning between these two causes is critical for monitoring glacier-clad volcanoes and has been controversial at Katla. For this new seismic cluster on the south flank, we regard volcano-related processes as more likely than glacial ones for the following reasons: 1) the seismic activity started during an unrest episode involving sudden melting of the glacier and a jökulhlaup; 2) the glacier stream is small and stagnant; 3) the seismicity remains regular and stable for years; 4) there is no apparent correlation with short-term weather changes, such as rainstorms. We suggest that a small, shallow hydrothermal system was activated on Katla's south flank in 2011, either by a minor magmatic injection or by changes of permeability in a local crack system.

  8. Generation, migration, and entrapment of Precambrian oils in the Eastern Flank Heavy Oil province, south Oman

    SciTech Connect

    Konert, G.; Van Den Brink, H.A. ); Visser, W. )

    1991-08-01

    The prolific Eastern Flank Heavy Oil province east of the South Oman Salt basin is unique because of the widespread occurrence of Precambrian source rocks from which the hydrocarbons originated. Fission-track analysis and burial studies suggest that most of these source rocks became mature and generated hydrocarbons in the Ordovician; subsequently, the source beds were uplifted and did not re-enter the oil window. Its uniqueness is also based on the all-important role played by Precambrian salt. The traps in Palaeozoic clastics were initially structured by halokinesis, and subsequently by salt dissolution. The latter process gradually removed the salt from the area is largely responsible for the present-day structure with palaeo-withdrawal basins inverted in present-day turtles. Present-day traps are mainly post-Late Jurassic in age, significantly post-dating the time of oil generation. Detailed field studies indicate that charge phases appear to correlate with periods of increased salt dissolution in the Late Jurassic-Early Cretaceous, Late Cretaceous, and Tertiary. Oil was probably stored in intermediate traps below and within the salt. It was gradually released upon progressive tilting of the basin flank; it migrated updip toward the basinward retreating salt edge, and subsequently (back) spilled into the stratigraphically younger traps. Also, removal of the top seal of intra-salt and sub-salt traps by salt dissolution allowed upward remigration. It follows that charge concepts in the Eastern Flank Heavy Oil province depend on defining salt-edge-related hydrocarbon release areas, rather than on kitchen modeling.

  9. The ridges of Europa: Extensions of adjacent topography onto their flanks

    NASA Astrophysics Data System (ADS)

    Greenberg, Richard; Sak, Peter B.

    2014-03-01

    The surface of Europa displays numerous generations of intersecting arrays of linear ridges. At some locations along these ridges, older ridges on adjacent terrain appear to extend up the flank of a more recent ridge. It has thus been suggested that the ridges may have formed by upturning of that adjacent terrain. However, the newer ridges generally appear to be material deposited over the older terrain. Here we consider how the morphology of the overprinted topography may have been inherited by the more recent ridges. An analogous process occurs along some sediment-starved convergent plate boundaries on Earth, where the poorly consolidated material of a frontal prism of an overriding plate is pushed over preexisting ridges and seamounts on the downgoing plate. The overriding plate inherits the morphology of the downgoing plate even though the actual extension of that topography has been underthrust and buried. A well-studied example lies offshore of Costa Rica where the Caribbean plate overrides the Cocos plate. Experiments show other mechanisms as well: mass-wasting down a flank can result in extensions of adjacent ridges thanks to the geometry imposed by a constant angle of repose; in addition, more pronounced extensions of the older ridges result if the new ridge grows as it is bulldozed from behind (i.e., from the central groove of a double ridge on Europa). The shapes of the ridge extensions are distinctly different in these two cases. If tidal pumping extrudes material to the surface at the center of a double ridge, it might drive the latter mechanism. The ridge extensions observed on the flanks of more recent ridges may provide a crucial diagnostic of dominant ridge-building mechanisms when and if additional images are obtained at high resolution from future exploration. In additional to their morphology, the distribution of ridge extensions at only isolated locales may also provide constraints on ridge formation processes and their diversity.

  10. A numerical study of the positive cloud-to-ground flash from the forward flank of normal polarity thunderstorm

    NASA Astrophysics Data System (ADS)

    Wang, Haoliang; Guo, Fengxia; Zhao, Tianliang; Qin, Meiou; Zhang, Lei

    2016-03-01

    This study investigates the electrical conditions favorable to the occurrence of positive cloud-to-ground (+ CG) flashes from the forward flank of normal polarity thunderstorm by building a three-dimensional stochastic lightning model and a normal polarity charge structure model. The lightning model well simulated the bilevel branched structure of lightning flash, which has been observed by previous studies. Simulation results indicate that the downshear extension of the charge layer to the forward flank would decrease the electric field of thunderstorm. When only the upper positive charge layer downshear extended to the forward flank, it could not give rise to the occurrence of + CG flashes. When both the upper positive and midlevel negative charge layers downshear extended to the forward flank, if the charge of the negative charge layer was less than the positive charge layer above it in the forward flank of the thunderstorm, that generated sufficient charge imbalance between these two charge layers, + CG flashes could originate from the forward flank; otherwise, IC flashes occur.

  11. North Kona slump: Submarine flank failure during the early(?) tholeiitic shield stage of Hualalai Volcano

    USGS Publications Warehouse

    Lipman, P.W.; Coombs, M.L.

    2006-01-01

    The North Kona slump is an elliptical region, about 20 by 60 km (1000-km2 area), of multiple, geometrically intricate benches and scarps, mostly at water depths of 2000-4500 m, on the west flank of Hualalai Volcano. Two dives up steep scarps in the slump area were made in September 2001, using the ROV Kaiko of the Japan Marine Science and Technology Center (JAMSTEC), as part of a collaborative Japan-USA project to improve understanding of the submarine flanks of Hawaiian volcanoes. Both dives, at water depths of 2700-4000 m, encountered pillow lavas draping the scarp-and-bench slopes. Intact to only slightly broken pillow lobes and cylinders that are downward elongate dominate on the steepest mid-sections of scarps, while more equant and spherical pillow shapes are common near the tops and bases of scarps and locally protrude through cover of muddy sediment on bench flats. Notably absent are subaerially erupted Hualalai lava flows, interbedded hyaloclastite pillow breccia, and/or coastal sandy sediment that might have accumulated downslope from an active coastline. The general structure of the North Kona flank is interpreted as an intricate assemblage of downdropped lenticular blocks, bounded by steeply dipping normal faults. The undisturbed pillow-lava drape indicates that slumping occurred during shield-stage tholeiitic volcanism. All analyzed samples of the pillow-lava drape are tholeiite, similar to published analyses from the submarine northwest rift zone of Hualalai. Relatively low sulfur (330-600 ppm) and water (0.18-0.47 wt.%) contents of glass rinds suggest that the eruptive sources were in shallow water, perhaps 500-1000-m depth. In contrast, saturation pressures calculated from carbon dioxide concentrations (100-190 ppm) indicate deeper equilibration, at or near sample sites at water depths of -3900 to -2800 m. Either vents close to the sample sites erupted mixtures of undegassed and degassed magmas, or volatiles were resorbed from vesicles during

  12. "Isolated Spontaneous Renal Artery Thrombosis - A Rare Cause of Acute Flank Pain".

    PubMed

    Raghavendran, M; Sarkar, Mrityunjoy; Kumar, Kiran G

    2016-11-01

    Many patients present with severe abdominal pain. Renal Artery Thrombosis (RAT) is rare, serious and misdiagnosed. RAT has been well described in association with various disorders, but isolated spontaneously occurring RAT is rare and only 2 cases have been described as of date. We present a case of flank pain presenting to emergency for evaluation and discuss the clinical aspects and management. We would like to stress on the important role of serum LDH levels and CT scan in RAT. Early diagnosis may result in salvage of organ by minimally invasive techniques. Late diagnosis will almost always result in nephrectomy. PMID:27617211

  13. Allele capture by selection for flanking markers: A new method for analyzing multigenic traits

    SciTech Connect

    Harrison, D.E.; Roderick, T.H.; Paigen, K.

    1995-12-31

    in complex living organisms like mammals, most important processes are controlled by sets of interacting genes organized in biological pathways. A vital area of research during the coming decades will be to identify the genes that regulate such pathways and to analyze their functions. We here outline a new procedure to accomplish this: allele capture using flanking markers. Here illustrated for mice, it should be useful for all organisms in which adequate numbers of marker genes are available. This procedure combines mankind`s oldest and best proven logical technique, selective breeding, with the modern technologies of molecular markers, linkage analyses and computer programs. 7 refs.

  14. Territory Tenure Increases with Repertoire Size in Brownish-Flanked Bush Warbler

    PubMed Central

    Xia, Canwei; Wei, Chentao; Zhang, Yanyun

    2015-01-01

    Song repertoire size is often cited as a classic example of a secondary sexual trait in birds. Models of sexual selection and empirical tests of their predictions have often related secondary sexual traits to longevity. However, the relationship between repertoire size and longevity is unclear. Using capture-mark-recapture studies in two populations of the brownish-flanked bush warbler Cettia fortipes, we found that males with a repertoire size of three maintained territory tenure for a longer duration than did males with a repertoire size of two. These results provide evidence that even a minimal difference in repertoire size can serve as a potential signal of territory tenure capability. PMID:25822524

  15. Geochemistry of summit fumarole vapors and flanking thermal/mineral waters at Popocatepetl Volcano, Mexico

    SciTech Connect

    Werner, C.; Goff, F.; Janik, C.J.

    1997-06-01

    Popocatepetl Volcano is potentially devastating to populations living in the greater Mexico City area. Systematic monitoring of fumarole gases and flanking thermal/mineral springs began in early 1994 after increased fumarolic and seismic activity were noticed in 1991. These investigations had two major objectives: (1) to determine if changes in magmatic conditions beneath Popocatepetl might be reflected by chemical changes in fumarolic discharges and (2) to determine if thermal/mineral spring waters in the vicinity of Popocatepetl are geochemically related to or influences by the magmatic system. This report summarizes results from these two discrete studies.

  16. Rapid detection and sequencing of alleles in the 3' flanking region of the interleukin-6 gene.

    PubMed Central

    Bowcock, A M; Ray, A; Erlich, H; Sehgal, P B

    1989-01-01

    The 3' flanking region of the interleukin 6 gene is polymorphic due to insertions of different size. Within this region lies a sequence of approximately 500 base pairs that is AT rich. Based on flanking sequence information we have constructed oligonucleotides which prime the polymerase chain reaction (PCR) and amplify this AT rich region. The amplification products visualized by agarose gel electrophoresis gave fragment sizes for both homozygous and heterozygous individuals that were concordant with those observed by conventional genomic blotting techniques. Alleles that could not be typed by Southern analysis were resolved with this approach. These results illustrate the value of PCR for the rapid detection of length polymorphisms such as those due to variable numbers of tandem repeats. In contrast to RFLP analysis this procedure takes less than a day to perform, is cheaper, avoids the use of radioactivity and requires far less substrate DNA. Three different human alleles were sequenced, and differences were detected that were due to both large duplications and loss of one or two bases, suggesting that AT rich regions identify highly polymorphic loci. The same primers also amplified non-human primate DNA, allowing a comparison of the human sequence with that of the common chimpanzee and baboon. Images PMID:2789373

  17. Flanking sequence determination and specific PCR identification of transgenic wheat B102-1-2.

    PubMed

    Cao, Jijuan; Xu, Junyi; Zhao, Tongtong; Cao, Dongmei; Huang, Xin; Zhang, Piqiao; Luan, Fengxia

    2014-01-01

    The exogenous fragment sequence and flanking sequence between the exogenous fragment and recombinant chromosome of transgenic wheat B102-1-2 were successfully acquired using genome walking technology. The newly acquired exogenous fragment encoded the full-length sequence of transformed genes with transformed plasmid and corresponding functional genes including ubi, vector pBANF-bar, vector pUbiGUSPlus, vector HSP, reporter vector pUbiGUSPlus, promoter ubiquitin, and coli DH1. A specific polymerase chain reaction (PCR) identification method for transgenic wheat B102-1-2 was established on the basis of designed primers according to flanking sequence. This established specific PCR strategy was validated by using transgenic wheat, transgenic corn, transgenic soybean, transgenic rice, and non-transgenic wheat. A specifically amplified target band was observed only in transgenic wheat B102-1-2. Therefore, this method is characterized by high specificity, high reproducibility, rapid identification, and excellent accuracy for the identification of transgenic wheat B102-1-2. PMID:24274014

  18. Stratigraphy and Characterization of Volcanic Deposits on the Northwestern Flanks of Mt. Makiling, Laguna, Philippines

    NASA Astrophysics Data System (ADS)

    Ybanez, R. L.; Bonus, A. A. B.; Judan, J. M.; Racoma, B. A.; Morante, K. A. M.; Balangue, M. I. R. D.

    2014-12-01

    Mt. Makiling is an inactive stratovolcano located in the province of Laguna. Semi-detailed geologic field mapping on the northwestern low-level flanks and apron of the volcano was conducted. Exposures reveal a volcanic terrain hosting a wide variety of volcanic rocks: lava flows, pyroclastic surges, pyroclastic flows, and tuff deposits. Stratigraphic logging of the volcanic deposits showed differences in occurrence of the deposit types as well as their characteristics. The pyroclastic flow deposits are found at the base of the column overlain by pyroclastic surges which were more common in the area. Capping the pyroclastic surges is a thin layer of tuffaceous units. Isolated deposits of lava flows of andesitic composition were mapped in the western flank of Mt. Makiling. These varying volcanic deposits are derived from different eruptive activities of Mt. Makiling, with at least three separate eruptive episodes indicated by the exposed deposits. Two separate explosive eruptions are marked by two different pyroclastic deposits, while an effusive episode, marked by andesitic lava flows, can also be identified. The pyroclastic surge deposit is uncharacteristically thick, around a hundred meters or more exposed, providing further questions as to the magnitude of past eruptions or the mechanism of pyroclastic material deposition around the volcano. Mt. Makiling, thus, has historically undergone different eruption types, but still releases generally the same material composition across varying deposits: intermediate or andesitic composition. This is consistent with the trend of Philippine volcanoes, and with the Macolod corridor which hosts this volcanic system.

  19. Low-temperature thermochronology of the flanks of the southern Upper Rhine Graben

    NASA Astrophysics Data System (ADS)

    Timar-Geng, Zoltan; Fügenschuh, Bernhard; Wetzel, Andreas; Dresmann, Horst

    2006-07-01

    The Upper Rhine Graben (URG) is the most perceptible part of the European Cenozoic Rift System. Uplifted Variscan basement of the Black Forest and the Vosges forms the flanks of the southern part of the graben. Apatite and zircon fission-track (FT) analyses indicate a complex low-temperature thermal history of the basement that was deciphered by inverse modelling of FT parameters. The models were tested against the observed data and independent geological constraints. The zircon FT ages of 28 outcrop samples taken along an E-W trending transect across the Black Forest and the Vosges range from 136 to 312 Ma, the apatite FT ages from 20 to 83 Ma. The frequency distributions of confined track lengths are broad and often bimodal in shape indicating a complex thermal history. Cooling below 120°C in the Early Cretaceous to Palaeogene was followed by a discrete heating episode during the late Eocene and subsequent cooling to surface temperature. The modelled time-temperature ( t- T) paths point to a total denudation of the flanks of URG in the range of 1.0-1.7 km for a paleogeothermal gradient of 60°C/km, and 1.3-2.2 km for a paleogeothermal gradient of 45°C/km since the late Eocene.

  20. Insulators recruit histone methyltransferase dMes4 to regulate chromatin of flanking genes

    PubMed Central

    Lhoumaud, Priscillia; Hennion, Magali; Gamot, Adrien; Cuddapah, Suresh; Queille, Sophie; Liang, Jun; Micas, Gael; Morillon, Pauline; Urbach, Serge; Bouchez, Olivier; Severac, Dany; Emberly, Eldon; Zhao, Keji; Cuvier, Olivier

    2014-01-01

    Chromosomal domains in Drosophila are marked by the insulator-binding proteins (IBPs) dCTCF/Beaf32 and cofactors that participate in regulating long-range interactions. Chromosomal borders are further enriched in specific histone modifications, yet the role of histone modifiers and nucleosome dynamics in this context remains largely unknown. Here, we show that IBP depletion impairs nucleosome dynamics specifically at the promoters and coding sequence of genes flanked by IBP binding sites. Biochemical purification identifies the H3K36 histone methyltransferase NSD/dMes-4 as a novel IBP cofactor, which specifically co-regulates the chromatin accessibility of hundreds of genes flanked by dCTCF/Beaf32. NSD/dMes-4 presets chromatin before the recruitment of transcriptional activators including DREF that triggers Set2/Hypb-dependent H3K36 trimethylation, nucleosome positioning, and RNA splicing. Our results unveil a model for how IBPs regulate nucleosome dynamics and gene expression through NSD/dMes-4, which may regulate H3K27me3 spreading. Our data uncover how IBPs dynamically regulate chromatin organization depending on distinct cofactors. PMID:24916307

  1. Character of shell beds flanking Herod Point shoal, southeastern Long Island Sound, New York

    USGS Publications Warehouse

    Poppe, L.J.; Williams, S.J.; Babb, Ivar G.

    2011-01-01

    High biogenic productivity, strong tidal currents, shoal topography, and short transport distances combine to favor shell-bed formation along the lower flanks of a cape-associated shoal off Herod Point on Long Island, New York. This shell bed has a densely packed, clast-supported fabric composed largely of undegraded surf clam (Spisula solidissima) valves. It is widest along the central part of the western flank of the shoal where topographic gradients are steep and a stronger flood tide results in residual flow. The bed is narrower and thinner toward the landward margins where currents are too weak to transport larger valves and topographic gradients are gentle, limiting bed-load transport mechanisms by which the shells are concentrated. Reconnaissance mapping off Roanoke Point suggests that shell beds are also present at the other cape-associated shoals off northeastern Long Island, where relatively similar geomorphic and oceanographic conditions exist. These shell beds are important to the Long Island Sound ecosystem because they provide complex benthic habitats of rough and hard substrates at the boundary between the muddy basin floor and mobile sand of the shoals. ?? 2011, the Coastal Education & Research Foundation (CERF).

  2. Microbial community in black rust exposed to hot ridge flank crustal fluids.

    PubMed

    Nakagawa, Satoshi; Inagaki, Fumio; Suzuki, Yohey; Steinsbu, Bjørn Olav; Lever, Mark Alexander; Takai, Ken; Engelen, Bert; Sako, Yoshihiko; Wheat, Charles Geoffrey; Horikoshi, Koki

    2006-10-01

    During Integrated Ocean Drilling Program Expedition 301, we obtained a sample of black rust from a circulation obviation retrofit kit (CORK) observatory at a borehole on the eastern flank of Juan de Fuca Ridge. Due to overpressure, the CORK had failed to seal the borehole. Hot fluids from oceanic crust had discharged to the overlying bottom seawater and resulted in the formation of black rust analogous to a hydrothermal chimney deposit. Both culture-dependent and culture-independent analyses indicated that the black-rust-associated community differed from communities reported from other microbial habitats, including hydrothermal vents at seafloor spreading centers, while it shared phylotypes with communities previously detected in crustal fluids from the same borehole. The most frequently retrieved sequences of bacterial and archaeal 16S rRNA genes were related to the genera Ammonifex and Methanothermococcus, respectively. Most phylotypes, including phylotypes previously detected in crustal fluids, were isolated in pure culture, and their metabolic traits were determined. Quantification of the dissimilatory sulfite reductase (dsrAB) genes, together with stable sulfur isotopic and electron microscopic analyses, strongly suggested the prevalence of sulfate reduction, potentially by the Ammonifex group of bacteria. Stable carbon isotopic analyses suggested that the bulk of the microbial community was trophically reliant upon photosynthesis-derived organic matter. This report provides important insights into the phylogenetic, physiological, and trophic characteristics of subseafloor microbial ecosystems in warm ridge flank crusts. PMID:17021232

  3. Overview of the geology of the east flank of the Front Range

    SciTech Connect

    Grose, T.L.T.

    1993-12-31

    This paper describes the geology encountered as part of a geology field trip. This stop identifies the monocline that forms the east flank of the Front Range and the west flank of the Denver Basin. The stratigraphic section viewed in cross section to the south is composed of: (1) migmatitic quartzo-feldspathic gneiss of Early Proterozoic age; (2) red sandstone and conglomerate of the Pennsylvanian-Permian Fountain Formation, 1,700 Feet thick; (3) Lyons Sandstone of Permian age, 200 feet thick; (4) shale, siltstone, and limestone of the Lykins Formation of Permian and Triassic age, 200 Feet thick; (5) gypsum, shale, and limestone of the Ralston Creek Formation of Jurassic age, 90 feet thick; (6) sandstone, shale, and limestone of the Morrison Formation of Jurassic age, 300 feet thick, locally containing dinosaur bones; (7) Lower Cretaceous Dakota Group, including the Lytle Formation of sandstone and conglomerate, 80 feet thick, and the South Platte Formation of sandstone and shale, 220 feet thick.

  4. Characterization of Bovine NANOG5′-flanking Region during Differentiation of Mouse Embryonic Stem Cells

    PubMed Central

    Jang, Hye-Jeong; Park, Hwan Hee; Linh, Tran Thi Thuy; Lee, Hak-Kyo; Song, Ki-Duk; Lee, Woon Kyu

    2015-01-01

    Embryonic stem cells (ESCs) have been used as a powerful tool for research including gene manipulated animal models and the study of developmental gene regulation. Among the critical regulatory factors that maintain the pluripotency and self-renewal of undifferentiated ESCs, NANOG plays a very important role. Nevertheless, because pluripotency maintaining factors and specific markers for livestock ESCs have not yet been probed, few studies of the NANOG gene from domestic animals including bovine have been reported. Therefore, we chose mouse ESCs in order to understand and compare NANOG expression between bovine, human, and mouse during ESCs differentiation. We cloned a 600 bp (−420/+181) bovine NANOG 5′-flanking region, and tagged it with humanized recombinant green fluorescent protein (hrGFP) as a tracing reporter. Very high GFP expression for bovine NANOG promoter was observed in the mouse ESC line. GFP expression was monitored upon ESC differentiation and was gradually reduced along with differentiation toward neurons and adipocyte cells. Activity of bovine NANOG (−420/+181) promoter was compared with already known mouse and human NANOG promoters in mouse ESC and they were likely to show a similar pattern of regulation. In conclusion, bovine NANOG 5-flanking region functions in mouse ES cells and has characteristics similar to those of mouse and human. These results suggest that bovine gene function studied in mouse ES cells should be evaluated and extrapolated for application to characterization of bovine ES cells. PMID:26580439

  5. Sequences flanking the core-binding site modulate glucocorticoid receptor structure and activity.

    PubMed

    Schöne, Stefanie; Jurk, Marcel; Helabad, Mahdi Bagherpoor; Dror, Iris; Lebars, Isabelle; Kieffer, Bruno; Imhof, Petra; Rohs, Remo; Vingron, Martin; Thomas-Chollier, Morgane; Meijsing, Sebastiaan H

    2016-01-01

    The glucocorticoid receptor (GR) binds as a homodimer to genomic response elements, which have particular sequence and shape characteristics. Here we show that the nucleotides directly flanking the core-binding site, differ depending on the strength of GR-dependent activation of nearby genes. Our study indicates that these flanking nucleotides change the three-dimensional structure of the DNA-binding site, the DNA-binding domain of GR and the quaternary structure of the dimeric complex. Functional studies in a defined genomic context show that sequence-induced changes in GR activity cannot be explained by differences in GR occupancy. Rather, mutating the dimerization interface mitigates DNA-induced changes in both activity and structure, arguing for a role of DNA-induced structural changes in modulating GR activity. Together, our study shows that DNA sequence identity of genomic binding sites modulates GR activity downstream of binding, which may play a role in achieving regulatory specificity towards individual target genes. PMID:27581526

  6. Electromagnetic evidence for an ancient avelanche caldera rim onthe south flank of mount merapi, indonesia

    SciTech Connect

    Kalscheuer, T.; Commer, M.; Helwig, S.L.; Hoerdt, A.; Tezkan, B.

    2006-02-28

    Long-Offset Transient Electromagnetic (LOTEM) data andVIBROTEM data from the south flank of Mount Merapi on Java island,Indonesia, are interpreted with one-dimensional (1D) inversions as wellas two-dimensional (2D) forward modelling. One-dimensional jointinversions of several components of the electromagnetic field withOccam's method reduce the number of equivalent models, which were derivedfrom inversions of single components and fit the data to a similarmisfit. The 1D results, together with results from other geophysicalmeasurements, serve as the basic model for further 2D forward modelling.The final model depicts a layering that follows the topography of thestrato-volcano. In the depth range of 500 m to 1000 m, the resistivity ofthe layers decreases rapidly downwards into a good conductor withresistivities below 10 OMEGAm. The deepest layer has a resistivity of 0.4OMEGAm which is quantitatively explained with a combination of salinefluids and hydrothermally altered minerals. Furthermore, the final modelsupports a hypothesis from the interpretation of central-loop TEM(Transient Electromagnetic) data that there is a fault structure belowthe southern flank, approximately 7.3 km south of the summit. To thenorth of the fault, the top of the good conductor is lowered from a depthof 500 m to 1000 m. We propose that the fault structure coincides with anancient avalanche caldera rim.

  7. Preliminary Results of Heat flow Measurements across the Eastern Flank of the Adare Trough, Antarctica

    NASA Astrophysics Data System (ADS)

    Hong, J. K.; Kim, Y. G.; Jin, Y. K.

    2015-12-01

    Marine heat flow measurement on the ridge is a direct and useful approach to know the current state of thermal regime below the lithosphere. Measurements in ridges located in the Antarctica are practically challenged by harsh conditions such as extensive and moving sea ice cover and stiff seafloor composed of diatomaceous sediments. We planned heat flow measurements across the Adare Trough, north of the Ross Sea, during the recent Korean icebreaker R/V Araon's Antarctic expedition (ANA05B; Dec 12th 2014-Feb 25th 2015) to get thermal information which is a missing piece in terms of geophysical data in this region to describe its asymmetric activity in spreading rate. Finally, we collected information only at three stations across the eastern flank of the Adare Trough over 70 km along with NBP9702 seismic line because of various limitations above. It is a preliminary result that observed heat flow seems significantly higher than estimated one from known magnetic anomaly age using a global age-heat flow curve. In order to conclude some suggestion, we need further studies regarding identification of 'real' heat flow from lithosphere, and increase of the number of data. More heat flow measurements will be carried out again on the eastern flank in the next Araon's Antarctic expedition (tentatively ANA06C; March 2016) to supplement the small number of data.

  8. Back-thrusting along the western flank of the Bighorn Mountain, Bighorn County,Wyoming

    SciTech Connect

    Noggle, K.S.

    1985-01-01

    Field evidence of westward back-thrusting, compartmentalized faulting, and tectonically-thinned fault wedges supports a thrust-generated model of uplift for the Bighorn Mountains. Encompassed within the Leavitt Reservoir Quadrangle are structures suggestive of westward basement-involved thrusting antithetic to the main eastward thrust direction of the Bighorn uplift. The mountain-flank region in this area is characterized by reverse-faulted blocks of Precambrian basement which are draped by a deformed Paleozoic cover. A reentrant along the mountain front coincides with an east-west compartmental boundary separating two distinct areas of structural discordance. North of this fault boundary, compression appears to have been accommodated by folding of the hanging wall block. To the south, Precambrian rocks exposed at the mountain-front overlie, and are in fault-contact with a tectonically-thinned, overturned wedge of Paleozoic and Mesozoic strata. Structures i the basinal portion of the Leavitt Reservoir Quadrangle include small-scale folds and a thrust-faulted anticline paralleling the NW-SE trend of the larger mountain-flank structures. Decollement may have occurred parallel to bedding planes within multiple stratigraphic horizons. This deformation probably represents concomitant basinward ramping of the sedimentary sequence in response to westward back-thrusting of Precambrian blocks during the Laramide Orogeny.

  9. A synergistic effect between cholesterol and tryptophan-flanked transmembrane helices modulates membrane curvature.

    PubMed

    van Duyl, Bianca Y; Meeldijk, Hans; Verkleij, Arie J; Rijkers, Dirk T S; Chupin, Vladimir; de Kruijff, Ben; Killian, J Antoinette

    2005-03-22

    The aim of this study was to gain insight into the structural consequences of hydrophobic mismatch for membrane proteins in lipid bilayers that contain cholesterol. For this purpose, tryptophan-flanked peptides, designed to mimic transmembrane segments of membrane proteins, were incorporated in model membranes of unsaturated phosphatidylcholine bilayers of varying thickness and containing varying amounts of cholesterol. Analysis of the lipid organization by (31)P NMR and cryo-TEM demonstrated the formation of an isotropic phase, most likely representing a cubic phase, which occurred exclusively in mixtures containing lipids with relatively long acyl chains. Formation of this phase was inhibited by incorporation of lysophosphatidylcholine. These results indicate that the isotropic phase is formed as a consequence of negative hydrophobic mismatch and that its formation is related to a negative membrane curvature. When either peptide or cholesterol was omitted from the mixture, isotropic-phase formation did not occur, not even when the concentrations of these compounds were significantly increased. This suggests that formation of the isotropic phase is the result of a synergistic effect between the peptides and cholesterol. Interestingly, isotropic-phase formation was not observed when the tryptophans in the peptide were replaced by either lysines or histidines. We propose a model for the mechanism of this synergistic effect, in which its dependence on the flanking residues is explained by preferential interactions between cholesterol and tryptophan residues. PMID:15766283

  10. Electromagnetic evidence for an ancient avalanche caldera rim on the south flank of Mount Merapi, Indonesia

    NASA Astrophysics Data System (ADS)

    Kalscheuer, T.; Commer, M.; Helwig, S. L.; Hördt, A.; Tezkan, B.

    2007-04-01

    Long-Offset Transient Electromagnetic (LOTEM) data and VIBROTEM data from the south flank of Mount Merapi on Java island, Indonesia, are interpreted with one-dimensional (1D) inversions as well as two-dimensional (2D) forward modelling. One-dimensional joint inversions of several components of the electromagnetic field with Occam's method reduce the number of equivalent models, which were derived from inversions of single components and fit the data to a similar misfit. The 1D results, together with results from other geophysical measurements, serve as the basic model for further 2D forward modelling. The final model depicts a layering that follows the topography of the strato-volcano. In the depth range of 500 m to 1000 m, the resistivity of the layers decreases rapidly downwards into a good conductor with resistivities below 10 Ωm. The deepest layer has a resistivity of 0.4 Ωm which is quantitatively explained with a combination of saline fluids and hydrothermally altered minerals. Furthermore, the final model supports a hypothesis from the interpretation of central-loop TEM (Transient Electromagnetic) data that there is a fault structure below the southern flank, approximately 7.3 km south of the summit. To the north of the fault, the top of the good conductor is lowered from a depth of 500 m to 1000 m. We propose that the fault structure coincides with an ancient avalanche caldera rim.

  11. Volcano flank instability in the Lesser Antilles Arc: Diversity of scale, processes, and temporal recurrence

    NASA Astrophysics Data System (ADS)

    Boudon, Georges; Le Friant, Anne; Komorowski, Jean-Christophe; Deplus, Christine; Semet, Michel P.

    2007-08-01

    The 1997 Boxing Day collapse, a remarkable feature of the ongoing eruption of Soufrière Hills on Montserrat, has prompted new interest in the study of volcano stability in the Lesser Antilles. Building on a few cases documented in the literature, we have now identified at least 47 flank collapse events on volcanoes of the Caribbean arc where this type of behavior is characteristic and repetitive. About 15 events occurred on active volcanoes within the last 12,000 years. In the northern part of the arc, flank collapses are repetitive, do not exceed 1 km3 in volume, occur in all directions, and are promoted by intense hydrothermal alteration and well-developed fracturing of the summit part of the edifices. In contrast, infrequent but large sector collapses, with volumes up to tens of km3, are typical of the southern volcanoes. They are always directed to the west as a result of the high overall slopes of the islands toward the deep back-arc Grenada Basin. Because Caribbean islands are small, a large part of the resulting debris avalanches have flowed into the sea thus contributing voluminous and sudden inputs of volcaniclastic sediments to the Grenada Basin. Deposits from such submarine flows have been identified during the recent AGUADOMAR and CARAVAL oceanographic cruises and traced to their source structures on land. Edifice collapses have a major influence on subsequent volcanic activity but also are of high concern because of their tsunamigenic potential.

  12. Exploration of tangential discontinuity structure of the dawn and dusk flank magnetopause

    NASA Astrophysics Data System (ADS)

    De Keyser, Johan; Maes, Lukas; Maggiolo, Romain; Haaland, Stein

    2015-04-01

    This contribution explores the tangential discontinuity configurations that are possible at the dawn and dusk flank magnetopause. The motivation for this study is the recent finding that the magnetopause current layer seems to be on average slightly thicker at the dawn flank than at dusk. The study is carried out by considering typical magnetosheath and magnetospheric plasma properties adjacent to the magnetopause and finding out which internal magnetopause structure is compatible with the given properties, if any. This is done by repeatedly running a kinetic model that self-consistently computes the internal structure of the tangential discontinuity magnetopause. The conclusions of this study support the viewpoint that, apart from dawn-dusk differences in the magnetosheath and/or magnetospheric conditions, one also has to consider an intrinsic asymmetry. For low magnetic shear in particular, the vxB electric field, with v the magnetosheath flow and B the geomagnetic field, points outward at dawn and inward at dusk. This convection electric field combines with the Chapman-Ferraro electric field that stems from the charge separation between the ions and electrons inside the magnetopause. Due to their different gyroradii, ions and electrons respond differently to a change of sign of the convection electric field, thus leading to dawn-dusk asymmetry of the internal structure of the magnetopause.

  13. A new method to identify flanking sequence tags in chlamydomonas using 3’-RACE

    PubMed Central

    2012-01-01

    Background The green alga Chlamydomonas reinhardtii, although a premier model organism in biology, still lacks extensive insertion mutant libraries with well-identified Flanking Sequence Tags (FSTs). Rapid and efficient methods are needed for FST retrieval. Results Here, we present a novel method to identify FSTs in insertional mutants of Chlamydomonas. Transformants can be obtained with a resistance cassette lacking a 3’ untranslated region (UTR), suggesting that the RNA that is produced from the resistance marker terminates in the flanking genome when it encounters a cleavage/polyadenylation signal. We have used a robust 3’-RACE method to specifically amplify such chimeric cDNAs. Out of 38 randomly chosen transformants, 27 (71%) yielded valid FSTs, of which 23 could be unambiguously mapped to the genome. Eighteen of the mutants lie within a predicted gene. All but two of the intragenic insertions occur in the sense orientation with respect to transcription, suggesting a bias against situations of convergent transcription. Among the 14 insertion sites tested by genomic PCR, 12 could be confirmed. Among these are insertions in genes coding for PSBS3 (possibly involved in non-photochemical quenching), the NimA-related protein kinase CNK2, the mono-dehydroascorbate reductase MDAR1, the phosphoglycerate mutase PGM5 etc.. Conclusion We propose that our 3’-RACE FST method can be used to build large scale FST libraries in Chlamydomonas and other transformable organisms. PMID:22735168

  14. Sediment transport along the Cap de Creus Canyon flank during a mild, wet winter

    NASA Astrophysics Data System (ADS)

    Martín, J.; Durrieu de Madron, X.; Puig, P.; Bourrin, F.; Palanques, A.; Houpert, L.; Higueras, M.; Sanchez-Vidal, A.; Calafat, A. M.; Canals, M.; Heussner, S.; Delsaut, N.; Sotin, C.

    2013-05-01

    Cap de Creus Canyon (CCC) is known as a preferential conduit for particulate matter leaving the Gulf of Lion continental shelf towards the slope and the basin, particularly in winter when storms and dense shelf water cascading coalesce to enhance the seaward export of shelf waters. During the CASCADE (CAscading, Storm, Convection, Advection and Downwelling Events) cruise in March 2011, deployments of recording instruments within the canyon and vertical profiling of the water column properties were conducted to study with high spatial-temporal resolution the impact of such processes on particulate matter fluxes. In the context of the mild and wet 2010-2011 winter, no remarkable dense shelf water formation was observed. On the other hand, the experimental setup allowed for the study of the impact of E-SE storms on the hydrographical structure and the particulate matter fluxes in the CCC. The most remarkable feature in terms of sediment transport was a period of dominant E-SE winds from 12 to 16 March, including two moderate storms (maximum significant wave heights = 4.1-4.6 m). During this period, a plume of freshened, relatively cold and turbid water flowed at high speeds along the southern flank of the CCC in an approximate depth range of 150-350 m. The density of this water mass was lighter than the ambient water in the canyon, indicating that it did not cascade off-shelf and that it merely downwelled into the canyon forced by the strong cyclonic circulation induced over the shelf during the storms and by the subsequent accumulation of seawater along the coast. Suspended sediment load in this turbid intrusion recorded along the southern canyon flank oscillated between 10 and 50 mg L-1, and maximum currents speeds reached values up to 90 cm s-1. A rough estimation of 105 tons of sediment was transported through the canyon along its southern wall during a 3-day-long period of storm-induced downwelling. Following the veering of the wind direction (from SE to NW) on

  15. A deep scar in the flank of Tenerife (Canary Islands): Geophysical contribution to tsunami hazard assessment

    NASA Astrophysics Data System (ADS)

    Coppo, Nicolas P.; Schnegg, Pierre-André; Falco, Pierik; Costa, Roberto

    2009-05-01

    Among the high-intensity on-Earth tsunami generating events, seismicity, submarine landslides, and volcano lateral collapses are the most important [Ward, S.H., 2001. Landslide tsunami. J. Geophy. Res. 106, 11201-11215; Holcomb, R.T., Searle, R.C., 1991. Large landslides from oceanic volcanoes. Mar. Geotech. 10, 19-32; Tinti, S., Bortolucci, E., Romagnoli, C., 2000. Computer simulations of tsunamis due to the sector collapse ar Stromboli, Italy. J. Volcano. Geotherm. Res. 96, 103-128; Ward, S.N., Day, S., 2003. Ritter Island Volcano — lateral collapse and the tsunami of 1888. Geophys. J. Int. 154, 891-902; MacGuire, W.J., 2003. Volcano instability and lateral collapse. Revista 1, 33-45]. Offshore bathymetry studies highlighted huge accumulations of large mass-waste flows (up to thousands cubic kilometres) inherited from past lateral collapses or submarine landslides [ Le Friant, A., Boudon, G., Deplus, C., Villemant, B., 2003. Large-scale flank collapse events during the activity of Montagne Pelée, Martinique, Lesser Antilles. J. Geophys. Res. 108, ECV13; Moore, J.G. et al., 1989. Prodigious submarine Landslides on the Hawaiian ridge. J. Geophys. Res. 94, 17465-17484] which spread over more than 100 km off the northern Tenerife (Canary Islands) coastline [Watts, A.B., Masson, D.G., 1995. A giant landslide on the north flank of Tenerife, Canary Islands. J. Geophys. Res. 100, 24487-24498]. Although mechanics and dynamics triggering such catastrophic events follow from combined complex processes and interactions [Hürlimann, M., Garcia-Piera, J.-O., Ledesma, A., 2000. Causes and mobility of large volcanic landslides: application to Tenerife, Canary Islands. J. Volcano. Geotherm. Res. 103, 121-134; Masson, D.G. et al., 2002. Slope failures on the flanks of the western Canary Islands. Earth-Sci. Rev. 57, 1-35; Reid, M.E., Sisson, T.W., Brien, D.L., 2001. Volcano collapse promoted by hydrothermal alteration and edifice shape, Mount Rainier, Washington. Geology 29, 779

  16. Salt flank imaging by integrated prestack depth migration of VSP and surface

    NASA Astrophysics Data System (ADS)

    Jang, Seonghyung; Kim, Tae-yeon

    2014-05-01

    Since Vertical Seismic Profile (VSP) data include wavefields which can measure directly physical properties between surface and geological interfaces, it is usually used for detecting dip, anisotropy, and reflection amplitude or waveform with respect to incidence angles. Though VSP covers the vicinity of the borehole comparing to the surface seismic, it gives high resolution and it is helpful to find the precise location of a well in the 3-D image from surface seismic data. Normally VSP data are smaller Fresnel zone and wider bandwidth than surface seismic data due to less absorption of the higher frequencies. It gives high fidelity reservoir image for effective reservoir monitoring such as 4D time-lapse seismic and carbon capture and storage. Prestack reverse time migration (RTM) is widely used for imaging the complex subsurface structures. RTM is a method for imaging the subsurface in depth domain using inner product of source wavefield extrapolation in forward and receiver wavefield extrapolation in backward. Since RTM is applicable to any source-receiver geometry, we can apply the same algorithm to VSP and surface seismic data. In this study RTM is implemented the integrated depth imaging of walk-away VSP and surface seismic data in order to have high resolution salt flank image. A synthetic test example includes a schematic flank of salt body with horizontal layers. The model - 8 km wide by 4 km depth - represents a simple salt body and background with velocity of 3.0 km/s for salt body and background velocity of 2.0 km/s. The source wavelet is zero-phase with a central frequency of 10 Hz for surface seismic and 20 Hz for VSP data. VSP data were recorded in the central borehole located 4.0 km from the left side of the model and the 151 receivers in central borehole were on a 20 m spacing between the depth of 0.5 km and 3.5 km. We acquired the surface seismic data using 101 surface sources on 40 m spacing between 2.3 km and 6.3 km. The 101 receivers on the

  17. Multidisciplinary geophysical study of the NE sector of the unstable flank of Etna volcano

    NASA Astrophysics Data System (ADS)

    Bonforte, Alessandro; Cocina, Ornella; Siniscalchi, Agata; Barberi, Graziella; Guglielmino, Francesco; Romano, Gerardo; Sicali, Simona; Tripaldi, Simona

    2015-04-01

    On volcanic areas, usually characterized by complex structural environments, a lot of independent geophysical studies are usually performed. The non-uniqueness of the geophysical inverse models, the different level of resolution and sensitivity of the results spurred us to integrate independent geophysical datasets and results collected on Mt. Etna volcano, in order to obtain more accurate and reliable model interpretation. Mt. Etna volcano is located along the eastern coast of Sicily and it is characterized by a complex structural setting. In this region, the general N-S compressive regime related to the Africa - Europe collision interacts with the WNW-ESE extensional regime associated to the Malta Escarpment dynamics, observable along the eastern coast of Sicily. At Mt Etna, a great number of studies concerns the existence of instability phenomena; a general eastward motion of the eastern flank of the volcano has been measured with always increasing detail and its relationship with the eruptive and magmatic activity is being investigated. The unstable flank appears bounded to the north by the E-W-trending Provenzana - Pernicana Fault System and to the SW by the NS Ragalna Fault system. Eastwards, this area is divided by several NW-SE trending faults. Recent studies consider this area as divided into several blocks characterized by different shape and kinematics. Ground deformation studies (GPS and InSAR) define the NE portion of the unstable flank as the most mobile one. In the frame of the MEDiterranean Supersites Volcanoes (MED-SUV) project, ground deformation data (GPS and INSAR), 3D seismicity, seismic tomography and two resistivity model profiles, have been analyzed together, in order to put some constraints on the deep structure of the NE sector of the unstable flank. Seismic data come from the permanent network run by the Istituto Nazionale di Geofisica e Vulcanologia (INGV) - Sezione di Catania, Osservatorio Etneo. Ground deformation data comes from In

  18. Control Study for Five-axis Dynamic Spin Rig Using Magnetic Bearings

    NASA Technical Reports Server (NTRS)

    Choi, Benjamin; Johnson, Dexter; Provenza, Andrew; Morrison, Carlos; Montague, Gerald

    2003-01-01

    The NASA Glenn Research Center (GRC) has developed a magnetic bearing system for the Dynamic Spin Rig (DSR) with a fully suspended shaft that is used to perform vibration tests of turbomachinery blades and components under spinning conditions in a vacuum. Two heteropolar radial magnetic bearings and a thrust magnetic bearing and the associated control system were integrated into the DSR to provide magnetic excitation as well as non-contact mag- netic suspension of a 15.88 kg (35 lb) vertical rotor with blades to induce turbomachinery blade vibration. For rotor levitation, a proportional-integral-derivative (PID) controller with a special feature for multidirectional radial excitation worked well to both support and shake the shaft with blades. However, more advanced controllers were developed and successfully tested to determine the optimal controller in terms of sensor and processing noise reduction, smaller rotor orbits, more blade vibration amplitude, and energy savings for the system. The test results of a variety of controllers that were demonstrated up to 10.000 rpm are shown. Furthermore, rotor excitation operation and conceptual study of active blade vibration control are addressed.

  19. Optimal Controller Tested for a Magnetically Suspended Five-Axis Dynamic Spin Rig

    NASA Technical Reports Server (NTRS)

    Choi, Benjamin B.

    2003-01-01

    NASA Glenn Research Center's Structural Mechanics and Dynamics Branch has developed a fully suspended magnetic bearing system for their Dynamic Spin Rig, which performs vibration tests of turbomachinery blades and components under spinning conditions in a vacuum. Two heteropolar radial magnetic bearings and a thrust magnetic bearing and the associated control system were integrated into the Dynamic Spin Rig to provide magnetic excitation as well as noncontact magnetic suspension of the 35-lb vertical rotor with blades to induce turbomachinery blade vibration (ref. 1). The new system can provide longer run times at higher speeds and larger vibration amplitudes for rotating blades. Also, it was proven that bearing mechanical life was substantially extended and flexibility was increased in the excitation orientation (direction and phasing).

  20. Recurrent large-scale landsliding on the west flank of La Palma, Canary Islands

    NASA Astrophysics Data System (ADS)

    Urgeles, Roger; Masson, Douglas G.; Canals, Miquel; Watts, Anthony B.; Le Bas, Tim

    1999-11-01

    A large area of debris avalanche deposits has been discovered on the western submarine flanks of the island of La Palma. Multibeam bathymetry and its derivative backscatter data, Towed Ocean Bottom Instrument (TOBI) sidescan sonar images, and 3.5 kHz and airgun seismic reflection data have been used to identify at least two, and possibly as many as four, major landslide events. The youngest of the events, the Cumbre Nueva Debris Avalanche, extends onshore into the valleys bounded by the Caldera de Taburiente and Cumbre Nueva Ridge, which mark the degraded collapse scars. Radiometric dating of the volcanic flows in the headwall indicate an age of between 536 and 125 ka for this landslide. The debris avalanche covers an area of 780 km2, has a maximum thickness of 500 m, and has an estimated volume of 95 km3. Older deposits, collectively referred to as the Playa de la Veta Debris Avalanche Complex, are probably, as the name indicates, an amalgamation of at least two or three events rather than the result of a single catastrophic failure. The Playa de la Veta Debris Avalanche Complex is associated onshore with an unconformity dated as late Matuyama (1 Ma to 800 ka). It covers an area of 1200 km2, has a maximum thickness of 1300 m, and may represent a total volume of up to 650 km3. The greater thicknesses and limited areas occupied by debris avalanches on the western flank of La Palma, compared to other landslides in the Canary Archipelago, suggest that the La Palma landslide masses have relatively low mobility. The different debris avalanche lobes formed by each landslide event are separated by channels 2-2.5 km wide. The clear relationship between channel position and the boundaries of each debris avalanche lobe indicates that debris avalanches control later channel formation and pathways. The relief of the submarine flanks of the La Palma volcanoes, in the areas of island slope unaffected by landslides, is mainly the result of constructional volcanic processes

  1. Ecological Resilience and Resistance in the Hyper Diverse Forests on the Eastern Andean Flank (Mera, Ecuador)

    NASA Astrophysics Data System (ADS)

    Keen, H. F.; Gosling, W. D.; Montoya, E.; Sherlock, S.; Mothes, P. A.

    2014-12-01

    Today the Neotropics contain some of the world's most biodiverse and threatened ecosystems. Sediments obtained from two radiocarbon infinite (>48,000 years) stratigraphic sections on the eastern Andean flank, provide new insight into the relationship between biodiversity and disturbance during the Pleistocene (~200,000 years). Pollen analysis of modern and fossil material indicates that hyper diverse forest vegetation has been a feature of the Andean flank landscape for 100,000 years (pollen richness: modern = 44, fossil = 48). Correlation of past vegetation with disturbance events (volcanic and fluvial) indicates the response of hyper-diverse forest to past landscape scale change. Pollen records from near Mera (01°27 S, 78°06 W; 1117 m asl) indicate two major changes in the pollen assemblage, with forest communities dominated by: i) Hedyosmum-Alnus-Ilex, and ii) Combretaceae-Melastomataceae-Myrtaceae. These two pollen assemblages most closely resemble modern vegetation cloud forest (2500-3400m asl) and lower montane rain forest (700-2499 m asl) respectively. Sedimentary evidence suggests that at least 21 volcanic events and three changes in the local fluvial regime perturbed the regional landscape during the period of deposition. However, there is no evidence for volcanic or fluvial disturbance events causing a persistent change in vegetation community. Volcanic events (tephra deposits) are associated with increased fire (charcoal particles), and changes in vegetation (pollen grains); however, within ~50cm of sediment accumulation above each tephra, pollen assemblages revert to pre-deposition compositions. Increased fluvial influence (gravel deposits) is associated with elevated input of pollen from taxa today found at higher elevations (Podocarpus-Celtis). The input of high elevation taxa concomitant with fluvial deposits is most likely indicative of an increase in long-distance transport of pollen along water courses originating in the Andes. Our data indicate

  2. QM/MM studies reveal pathways leading to the quenching of the formation of thymine dimer photoproduct by flanking bases.

    PubMed

    Lee, Wook; Matsika, Spiridoula

    2015-04-21

    It is known that the formation of the photochemical product of thymine-thymine cyclobutane pyrimidine dimer (TT-CPD) formed upon UV excitation in DNA is significantly affected by the nature of the flanking bases, and that the oxidation potential of the flanking base correlates with the quenching of TT-CPD formation. However, the electronic details of this correlation have remained controversial. The quenching of thymine dimer formation exerted by flanking bases was suggested to be driven by both conformational and electronic effects. In the present study, we examine both of these effects using umbrella sampling and a quantum mechanical/molecular mechanical (QM/MM) approach for selected model systems. Our results demonstrate that a charge transfer (CT) state between the flanking base and the adjacent thymine base can provide a decay pathway for the population to escape from dimer formation, which eventually leads to the formation of an exciplex. The QM/MM vertical excitation energies also reveal that the oxidation potential of flanking bases correlates with the energy level of the CT state, thereby determining whether the CT state intersects with the state that can lead to dimer formation. The consistency between these results and experimentally obtained dimer formation rates implies that the quenching of dimer formation is mainly attributed to the decay pathway via the CT state. The present results further underline the importance of the electronic effects in quenching. PMID:25776223

  3. Integration of Expressed Sequence Tag Data Flanking Predicted RNA Secondary Structures Facilitates Novel Non-Coding RNA Discovery

    PubMed Central

    Krzyzanowski, Paul M.; Price, Feodor D.; Muro, Enrique M.; Rudnicki, Michael A.; Andrade-Navarro, Miguel A.

    2011-01-01

    Many computational methods have been used to predict novel non-coding RNAs (ncRNAs), but none, to our knowledge, have explicitly investigated the impact of integrating existing cDNA-based Expressed Sequence Tag (EST) data that flank structural RNA predictions. To determine whether flanking EST data can assist in microRNA (miRNA) prediction, we identified genomic sites encoding putative miRNAs by combining functional RNA predictions with flanking ESTs data in a model consistent with miRNAs undergoing cleavage during maturation. In both human and mouse genomes, we observed that the inclusion of flanking ESTs adjacent to and not overlapping predicted miRNAs significantly improved the performance of various methods of miRNA prediction, including direct high-throughput sequencing of small RNA libraries. We analyzed the expression of hundreds of miRNAs predicted to be expressed during myogenic differentiation using a customized microarray and identified several known and predicted myogenic miRNA hairpins. Our results indicate that integrating ESTs flanking structural RNA predictions improves the quality of cleaved miRNA predictions and suggest that this strategy can be used to predict other non-coding RNAs undergoing cleavage during maturation. PMID:21698286

  4. Integration of expressed sequence tag data flanking predicted RNA secondary structures facilitates novel non-coding RNA discovery.

    PubMed

    Krzyzanowski, Paul M; Price, Feodor D; Muro, Enrique M; Rudnicki, Michael A; Andrade-Navarro, Miguel A

    2011-01-01

    Many computational methods have been used to predict novel non-coding RNAs (ncRNAs), but none, to our knowledge, have explicitly investigated the impact of integrating existing cDNA-based Expressed Sequence Tag (EST) data that flank structural RNA predictions. To determine whether flanking EST data can assist in microRNA (miRNA) prediction, we identified genomic sites encoding putative miRNAs by combining functional RNA predictions with flanking ESTs data in a model consistent with miRNAs undergoing cleavage during maturation. In both human and mouse genomes, we observed that the inclusion of flanking ESTs adjacent to and not overlapping predicted miRNAs significantly improved the performance of various methods of miRNA prediction, including direct high-throughput sequencing of small RNA libraries. We analyzed the expression of hundreds of miRNAs predicted to be expressed during myogenic differentiation using a customized microarray and identified several known and predicted myogenic miRNA hairpins. Our results indicate that integrating ESTs flanking structural RNA predictions improves the quality of cleaved miRNA predictions and suggest that this strategy can be used to predict other non-coding RNAs undergoing cleavage during maturation. PMID:21698286

  5. Limited approach to the right flank for placement of a duodenostomy tube.

    PubMed

    Novo, R E; Churchill, J; Faudskar, L; Lipowitz, A J

    2001-01-01

    A new enterostomy tube placement technique is described for provision of nutrients into the duodenum. Placement of the duodenostomy tube (d-tube) is performed through a limited right flank approach under sedation and local anesthesia. Seven client-owned animals (three dogs and four cats) requiring enteral nutritional support were selected for d-tube placement. Patients were fed via the d-tube for two to 28 days. Complications included discomfort when manipulating and exteriorizing the duodenum, discomfort with bolus feedings, local cellulitis, and tube site infection. All complications resolved without further incident. This technique should be considered in patients that are not good candidates for prolonged general anesthesia or esophageal or gastric feeding, or patients being mechanically ventilated. PMID:11300529

  6. Chandra X-ray Observations of Young Clusters. Volume II; Orion Flanking Fields Data

    NASA Technical Reports Server (NTRS)

    Ramirez, Solange V.; Rebull, Luisa; Stauffer, John; Strom, Stephen; Hillenbrand, Lynne; Hearty, Thomas; Kopan, Eugene L.; Pravdo, Steven; Makidon, Russell; Jones, Burton

    2004-01-01

    We present results of Chandra observations of two flanking fields (FFs) in Orion, outside the Orion Nebula Cluster (ONC). The observations were taken with the ACIS-I camera with an exposure time of about 48 ks each field. We present a catalog of 417 sources, which includes X-ray luminosity, optical and infrared photometry, and X-ray variability information. We have found 91 variable sources, 33 of which have a flarelike light curve and 11 of which have a pattern of a steady increase or decrease over a 10 hr period. The optical and infrared photometry for the stars identified as X-ray sources are consistent with most of these objects being pre-main-sequence stars with ages younger than 10 Myr. We present evidence for an age difference among the X-ray-selected samples of NGC 2264, Orion FFs, and ONC, with NGC 2264 being the oldest and ONC being the youngest.

  7. Evaluation of thyroid function in dogs suffering from recurrent flank alopecia.

    PubMed Central

    Daminet, S; Paradis, M

    2000-01-01

    Thyroid function was assessed in euthyroid dogs (n = 20), dogs suffering from canine recurrent flank alopecia (CRFA, n = 18), and hypothyroid dogs (n = 21). Blood samples obtained from all dogs in each group were assayed for total thyroxine (TT4), thyrotropin (TSH), and thyroglobulin autoantibody (TgAA) serum concentrations. Total T4 and TSH serum concentrations were significantly decreased and increased, respectively, in the hypothyroid group compared with the other 2 groups. No significant differences in TT4 and TSH serum values were found between the euthyroid and CRFA groups. Thyroglobulin autoantibodies were detected in 10, 11.1, and 61.9% of euthyroid dogs, dogs with CRFA, and hypothyroid dogs, respectively. In conclusion, dogs suffering from CRFA have a normal thyroid function, and the determination of TT4 and TSH serum concentrations allows differentiation of these dogs from dogs with hypothyroidism, in most cases. Occasionally, the 2 diseases can be concomitant. PMID:10992988

  8. Histology of melanic flank and opercular color pattern elements in the Firemouth Cichlid, Thorichthys meeki.

    PubMed

    Beeching, Simon C; Glass, Brock A; Rehorek, Susan J

    2013-07-01

    Dark melanic color pattern elements, such as bars, stripes, and spots, are common in the skin of fishes, and result from the differential distribution and activity of melanin-containing chromatophores (melanophores). We determined the histological basis of two melanic color pattern elements in the integument of the Firemouth Cichlid, Thorichthys meeki. Vertical bars on the flanks were formed by three layers of dermal melanophores, whereas opercular spots were formed by four layers (two lateral and two medial) in the integument surrounding the opercular bones. Pretreatment of opercular tissue with potassium and sodium salts effectively concentrated or dispersed intracellular melanosomes. Regional differences in epidermal structure, scale distribution, and connective tissues were also identified. PMID:23450665

  9. Flank instability of Stromboli volcano detected by long-term GB-InSAR monitoring

    NASA Astrophysics Data System (ADS)

    Intrieri, Emanuele; Di Traglia, Federico; Del Ventisette, Chiara; Gigli, Giovanni; Mugnai, Francesco; Luzi, Guido; Casagli, Nicola

    2013-04-01

    Stromboli is a volcanic island in Southern Italy characterized by explosions of variable energy every 10-20 minutes and periodically interrupted by more energetic blasts emitting large volumes of material. The pressurization of volatile-poor, high-porphyritic magma column that is gas-recharged by the deep-seated, volatile-rich, low-porphyritic magma precedes such events and produces deformations on the NW flank of the volcano, called Sciara del Fuoco. By integrating geomorphological observations with long-term deformations measured by a ground-based interferometric radar since December 2007, we managed to map two landslides whose movements are strongly related with volcanic activity. Deformation patterns obtained through a novel long-term analysis of GB-InSAR data, usually exploited for real time monitoring and early warning of slope with high risk, permitted us to hypothesize the type of movement and depth for both landslides. During the last 5 years their deformation velocity reached a maximum of more than 2 mm/day. Furthermore their position allowed us to affirm that the effusive vent formed in 2007 at 400 m a.s.l., was the result of the deflection of a feeder dike operated by landslide fractures, thus showing the important role of geomorphological discontinuities in volcanic environments. The study of slope instability of the Sciara del Fuoco is also relevant with reference to tsunami risk, especially considering that mass movements similar to those detected may take place also in other portions of the volcano flank not visible by the current installation.

  10. Phenotypic characterization of patients with deletions in the 3'-flanking SHOX region.

    PubMed

    Kant, Sarina G; Broekman, Sander J; de Wit, Caroline C; Bos, Marloes; Scheltinga, Sitha A; Bakker, Egbert; Oostdijk, Wilma; van der Kamp, Hetty J; van Zwet, Erik W; van der Hout, Annemieke H; Wit, Jan M; Losekoot, Monique

    2013-01-01

    Context. Leri-Weill dyschondrosteosis is a clinically variable skeletal dysplasia, caused by SHOX deletion or mutations, or a deletion of enhancer sequences in the 3'-flanking region. Recently, a 47.5 kb recurrent PAR1 deletion downstream of SHOX was reported, but its frequency and clinical importance are still unknown. Objective. This study aims to compare the clinical features of different sizes of deletions in the 3'-flanking SHOX region in order to determine the relevance of the regulatory sequences in this region. Design. We collected DNA from 28 families with deletions in the 3'-PAR1 region. Clinical data were available from 23 index patients and 21 relatives. Results. In 9 families (20 individuals) a large deletion ( ∼ 200-900 kb) was found and in 19 families (35 individuals) a small deletion was demonstrated, equal to the recently described 47.5 kb PAR1 deletion. Median height SDS, sitting height/height ratio SDS and the presence of Madelung deformity in patients with the 47.5 kb deletion were not significantly different from patients with larger deletions. The index patients had a median height SDS which was slightly lower than in their affected family members (p = 0.08). No significant differences were observed between male and female patients. Conclusions. The phenotype of patients with deletions in the 3'-PAR1 region is remarkably variable. Height, sitting height/height ratio and the presence of Madelung deformity were not significantly different between patients with the 47.5 kb recurrent PAR1 deletion and those with larger deletions, suggesting that this enhancer plays an important role in SHOX expression. PMID:23638371

  11. The interaction of polyglutamine peptides with lipid membranes is regulated by flanking sequences associated with huntingtin.

    PubMed

    Burke, Kathleen A; Kauffman, Karlina J; Umbaugh, C Samuel; Frey, Shelli L; Legleiter, Justin

    2013-05-24

    Huntington disease (HD) is caused by an expanded polyglutamine (poly(Q)) repeat near the N terminus of the huntingtin (htt) protein. Expanded poly(Q) facilitates formation of htt aggregates, eventually leading to deposition of cytoplasmic and intranuclear inclusion bodies containing htt. Flanking sequences directly adjacent to the poly(Q) domain, such as the first 17 amino acids on the N terminus (Nt17) and the polyproline (poly(P)) domain on the C-terminal side of the poly(Q) domain, heavily influence aggregation. Additionally, htt interacts with a variety of membraneous structures within the cell, and Nt17 is implicated in lipid binding. To investigate the interaction between htt exon1 and lipid membranes, a combination of in situ atomic force microscopy, Langmuir trough techniques, and vesicle permeability assays were used to directly monitor the interaction of a variety of synthetic poly(Q) peptides with different combinations of flanking sequences (KK-Q35-KK, KK-Q35-P10-KK, Nt17-Q35-KK, and Nt17-Q35-P10-KK) on model membranes and surfaces. Each peptide aggregated on mica, predominately forming extended, fibrillar aggregates. In contrast, poly(Q) peptides that lacked the Nt17 domain did not appreciably aggregate on or insert into lipid membranes. Nt17 facilitated the interaction of peptides with lipid surfaces, whereas the poly(P) region enhanced this interaction. The aggregation of Nt17-Q35-P10-KK on the lipid bilayer closely resembled that of a htt exon1 construct containing 35 repeat glutamines. Collectively, this data suggests that the Nt17 domain plays a critical role in htt binding and aggregation on lipid membranes, and this lipid/htt interaction can be further modulated by the presence of the poly(P) domain. PMID:23572526

  12. Whale phylogeny and rapid radiation events revealed using novel retroposed elements and their flanking sequences

    PubMed Central

    2011-01-01

    Background A diversity of hypotheses have been proposed based on both morphological and molecular data to reveal phylogenetic relationships within the order Cetacea (dolphins, porpoises, and whales), and great progress has been made in the past two decades. However, there is still some controversy concerning relationships among certain cetacean taxa such as river dolphins and delphinoid species, which needs to be further addressed with more markers in an effort to address unresolved portions of the phylogeny. Results An analysis of additional SINE insertions and SINE-flanking sequences supported the monophyly of the order Cetacea as well as Odontocete, Delphinoidea (Delphinidae + Phocoenidae + Mondontidae), and Delphinidae. A sister relationship between Delphinidae and Phocoenidae + Mondontidae was supported, and members of classical river dolphins and the genera Tursiops and Stenella were found to be paraphyletic. Estimates of divergence times revealed rapid divergences of basal Odontocete lineages in the Oligocene and Early Miocene, and a recent rapid diversification of Delphinidae in the Middle-Late Miocene and Pliocene within a narrow time frame. Conclusions Several novel SINEs were found to differentiate Delphinidae from the other two families (Monodontidae and Phocoenidae), whereas the sister grouping of the latter two families with exclusion of Delphinidae was further revealed using the SINE-flanking sequences. Interestingly, some anomalous PCR amplification patterns of SINE insertions were detected, which can be explained as the result of potential ancestral SINE polymorphisms and incomplete lineage sorting. Although a few loci were potentially anomalous, this study demonstrated that the SINE-based approach is a powerful tool in phylogenetic studies. Identifying additional SINE elements that resolve the relationships in the superfamily Delphinoidea and family Delphinidae will be important steps forward in completely resolving cetacean phylogenetic

  13. Volatile emissions from the crater and flank of Oldoinyo Lengai volcano, Tanzania

    NASA Astrophysics Data System (ADS)

    Koepenick, K. W.; Brantley, S. L.; Thompson, J. M.; Rowe, G. L.; Nyblade, A. A.; Moshy, C.

    1996-06-01

    As a comparison to airborne infrared (IR) flux measurements, ground-based sampling of fumarole and soil gases was used to characterize the quiescent degassing of CO2 from Oldoinyo Lengai volcano. Aerial and ground-based measurements are in good agreement: ˜75% of the aerially measured CO2 flux at Lengai (0.05-0.06 × 1012 mol yr-1 or 6000-7200 tonnes CO2 d-1) can be attributed to seven large crater vents. In contrast to Etna and Vulcano Island, where 15-50% of the total CO2 flux emanates diffusely through the volcanic flanks, diffuse emissions were measured only within 500 m of the crater rim at Lengai, contributing <2% of the total flux. The lack of extensive flank emissions may reflect the dimensions of the magma chamber and/or the lack of a shallow fluid flow system. Thermodynamic restoration of fumarole analyses shows that gases are the most CO2-rich and H2O-poor reported for any volcano, containing 64-74% CO2, 24-34% H2O, 0.88-1.0% H2, 0.1-0.4% CO and <0.1% H2S, HCl, HF, and CH4. Volatile emissions of S, Cl, and F at Oldoiyno Lengai are estimated as 4.5, 1.5, and 1.0 × 107 mol yr-1, respectively. Accuracy of the airborne technique was also assessed by measuring the C emission rate from a coal-burning power plant. CO2 fluxes were measured within ±10% near the plant; however, poor resolution at increased distances caused an underestimation of the flux by a factor of 2. The relatively large CO2 fluxes measured for alkaline volcanoes such as Oldoinyo Lengai or Etna may indicate that midplate volcanoes represent a large, yet relatively unknown, natural source of CO2.

  14. Volatile emissions from the crater and flank of Oldoinyo Lengai volcano, Tanzania

    USGS Publications Warehouse

    Koepenick, K.W.; Brantley, S.L.; Thompson, J.M.; Rowe, G.L.; Nyblade, A.A.; Moshy, C.

    1996-01-01

    As a comparison to airborne infrared (IR) flux measurements, ground-based sampling of fumarole and soil gases was used to characterize the quiescent degassing of CO2 from Oldoinyo Lengai volcano. Aerial and ground-based measurements are in good agreement: ???75% of the aerially measured CO2 flux at Lengai (0.05-0.06 ?? 1012 mol yr-1 or 6000-7200 tonnes CO2 d-1) can be attributed to seven large crater vents. In contrast to Etna and Vulcano Island, where 15-50% of the total CO2 flux emanates diffusely through the volcanic flanks, diffuse emissions were measured only within 500 m of the crater rim at Lengai, contributing < 2% of the total flux. The lack of extensive flank emissions may reflect the dimensions of the magma chamber and/or the lack of a shallow fluid flow system. Thermodynamic restoration of fumarole analyses shows that gases are the most CO2-rich and H2O-poor reported for any volcano, containing 64-74% CO2, 24-34% H2O, 0.88-1.0% H2, 0.1-0.4% CO and < 0.1% H2S, HCl, HF, and CH4. Volatile emissions of S, Cl, and F at Oldoiyno Lengai are estimated as 4.5, 1.5, and 1.0 ?? 107 mol yr-1, respectively. Accuracy of the airborne technique was also assessed by measuring the C emission rate from a coal-burning power plant. CO2 fluxes were measured within ??10% near the plant; however, poor resolution at increased distances caused an underestimation of the flux by a factor of 2. The relatively large CO2 fluxes measured for alkaline volcanoes such as Oldoinyo Lengai or Etna may indicate that midplate volcanoes represent a large, yet relatively unknown, natural source of CO2.

  15. RENAL RETENTION OF LIPID MICROBUBBLES: A POTENTIAL MECHANISM FOR FLANK DISCOMFORT DURING ULTRASOUND CONTRAST ADMINISTRATION

    PubMed Central

    Liu, Ya Ni; Khangura, Jaspreet; Xie, Aris; Belcik, J. Todd; Qi, Yue; Davidson, Brian P.; Zhao, Yan; Kim, Sajeevani; Inaba, Yoichi; Lindner, Jonathan R.

    2013-01-01

    Background The etiology for flank pain sometimes experienced during administration of ultrasound contrast agents is unknown. We investigated whether microbubble ultrasound contrast agents are retained within the renal microcirculation which could lead to either flow disturbance or local release of vasoactive and pain mediators downstream from complement activation. Methods Retention of lipid-shelled microbubbles in the renal microcirculation of mice was assessed by confocal fluorescent microscopy and contrast-enhanced ultrasound (CEU) imaging with dose-escalating intravenous injection. Studies were performed with size-segregated microbubbles to investigate physical entrapment, after glycocalyx degradation, and in wild-type and C3-deficient mice to investigate complement-mediated retention. Urinary bradykinin was measured before and after microbubbles. Renal CEU in human subjects (n=13) was performed 7–10 min after completion of lipid microbubble administration. Results In both mice and humans, microbubble retention was detected in the renal cortex by persistent CEU signal enhancement. Microbubble retention in mice was linearly related to dose and occurred almost exclusively in cortical glomerular microvessels. Microbubble retention did not affect microsphere-derived renal blood flow. Microbubble retention was not influenced by glycocalyx degradation nor by microbubble size, thereby excluding lodging, but was reduced by 90% (p<0.01) in C3-deficient mice. Urinary bradykinin increased by 65% five minutes after microbubble injection. Conclusion Lipid-shelled microbubbles are retained in the renal cortex due to complement-mediated interactions with glomerular microvascular endothelium. Microbubble retention does not adversely affect renal perfusion but does generate complement-related intermediates that are known to mediate nociception and could be responsible for flank pain. PMID:24035699

  16. The Interaction of Polyglutamine Peptides with Lipid Membranes Is Regulated by Flanking Sequences Associated with Huntingtin*

    PubMed Central

    Burke, Kathleen A.; Kauffman, Karlina J.; Umbaugh, C. Samuel; Frey, Shelli L.; Legleiter, Justin

    2013-01-01

    Huntington disease (HD) is caused by an expanded polyglutamine (poly(Q)) repeat near the N terminus of the huntingtin (htt) protein. Expanded poly(Q) facilitates formation of htt aggregates, eventually leading to deposition of cytoplasmic and intranuclear inclusion bodies containing htt. Flanking sequences directly adjacent to the poly(Q) domain, such as the first 17 amino acids on the N terminus (Nt17) and the polyproline (poly(P)) domain on the C-terminal side of the poly(Q) domain, heavily influence aggregation. Additionally, htt interacts with a variety of membraneous structures within the cell, and Nt17 is implicated in lipid binding. To investigate the interaction between htt exon1 and lipid membranes, a combination of in situ atomic force microscopy, Langmuir trough techniques, and vesicle permeability assays were used to directly monitor the interaction of a variety of synthetic poly(Q) peptides with different combinations of flanking sequences (KK-Q35-KK, KK-Q35-P10-KK, Nt17-Q35-KK, and Nt17-Q35-P10-KK) on model membranes and surfaces. Each peptide aggregated on mica, predominately forming extended, fibrillar aggregates. In contrast, poly(Q) peptides that lacked the Nt17 domain did not appreciably aggregate on or insert into lipid membranes. Nt17 facilitated the interaction of peptides with lipid surfaces, whereas the poly(P) region enhanced this interaction. The aggregation of Nt17-Q35-P10-KK on the lipid bilayer closely resembled that of a htt exon1 construct containing 35 repeat glutamines. Collectively, this data suggests that the Nt17 domain plays a critical role in htt binding and aggregation on lipid membranes, and this lipid/htt interaction can be further modulated by the presence of the poly(P) domain. PMID:23572526

  17. Characterization of the 5'-flanking region of the gene for the alpha chain of human fibrinogen.

    PubMed

    Hu, C H; Harris, J E; Davie, E W; Chung, D W

    1995-11-24

    The 5'-flanking region of the gene coding for the alpha chain of human fibrinogen was isolated, sequenced, and characterized. The principal site of transcription initiation was determined by primer extension analysis and the RNase protection assay and shown to be at an adenine residue located 55 nucleotides upstream from the initiator methionine codon, or 13,399 nucleotides down-stream from the polyadenylation site of the gene coding for the gamma chain. Transient expression of constructs containing sequentially deleted 5'-flanking sequences of the alpha chain gene fused to the chloramphenicol acetyltransferase reporter gene showed that the promoter was liver-specific and inducible by interleukin 6 (IL-6). The shortest DNA fragment with significant promoter activity and full response to IL-6 stimulation encompassed the region from -217 to +1 base pairs (bp). Although six potential IL-6 responsive sequences homologous to the type II IL-6 responsive element were present, a single sequence of CTGGGA localized from -122 to -127 bp was shown to be a functional element in IL-6 induction. A hepatocyte nuclear factor 1 (HNF-1) binding site, present from -47 to -59 bp, in combination with other upstream elements, was essential for liver-specific expression of the gene. A functional CCAAT/enhancer binding protein site (C/EBP, -134 to -142 bp) was also identified within 217 bp from the transcription initiation site. An additional positive element (-1393 to -1133 bp) and a negative element (-1133 to -749 bp) were also found in the upstream region of the alpha-fibrinogen gene. PMID:7499335

  18. Flank collapse triggered by intrusion: the Canarian and Cape Verde Archipelagoes

    NASA Astrophysics Data System (ADS)

    Elsworth, Derek; Day, Simon J.

    1999-12-01

    The potential to develop kilometer-scale instabilities on the flanks of intraplate volcanoes, typified by the Canary and Cape Verde Archipelagoes, is investigated. A primary triggering agent is forced injection of moderate-scale dikes, resulting in the concurrent development of mechanical and thermal fluid pressures along the basal décollement, and magmastatic pressures at the dike interface. These additive effects are shown capable of developing shallow-seated block instabilities for dike thicknesses of the order of 1 m, and horizontal lengths greater than about 1 km. For dikes that approach or penetrate the surface, and are greater in length than this threshold, the destabilizing influence of the magmastatic column is significant, and excess pore fluid pressures may not be necessary to initiate failure. The potentially destabilized block geometry changes from a flank-surface-parallel sliver for short dikes, to a deeper and less stable décollement as dike horizontal length builds and the effects of block lateral restraint diminish. For intrusions longer than about 1 km, the critical basal décollement dives below the water table and utilizes the complementary destabilizing influences of pore fluid pressures and magma "push" at the rear block-scarp. In addition to verifying the plausibility of suprahydrostatic pressures as capable of triggering failure on these volcanoes, timing of the onset of maximum instability may also be tracked. For events within the Cumbre Vieja (1949) and Fogo (1951, 1995) pre-effusive episodes, the observation of seismic activity within the first 1 week to 4 months is consistent with the predictions of thermal and mechanical pressurization.

  19. The rise flank trails left by migrating offsets of the equatorial East Pacific Rise axis

    SciTech Connect

    Lonsdale, P. )

    1989-01-10

    Sea Beam and magnetic surveys of the young (<1 Ma) rise flank around nontransform rise crest offsets at 5.5{degree}N, 4.9{degree}N, 3.4{degree}, 2.0{degree}N, and 2.8{degree}S mapped distinctive trails of obliquely lineated, highly magnetic crust that spreads from the characteristically curving overlapping rift zones. A Deep Tow survey around the small (1.5 km) 3.9{degree}N offset and the large (27 km) 2.0{degree}N offset provided more detailed infromation on the formation of crust in the offset trails, and of the structure of tectoniclly modified crust at interrift rise crest sites. Patches of interrift crust, which forms deep overlap basins at medium size offsets and basins and plateaus of rotated abyssal hills at large offsets, are periodically shed from the axial zone, together with abandoned portions of overlapped rift zone, to become important elements of the rise flank trails. The oblique aximuths of the paired 'fracture zone' trails that diverge from the rise crest offsets show that most have migrated along the rise crest at average speeds of 25-125 mm/yr. Net movement of the 27-km 2.8{degree}S offset has been slower, with alternating periods of rapid northward and southward migration. Information on the migration history of the surveyed offsets was supplemented by inferring the migration direction of another eight offsets on the equatorial East Pacific Rise (EPR) whose trails were less throughly mapped. Most offsets of the southern Pacific-Cocos boundary have migrated south, and most on the northern Pacific-Nazca boundary have migrated south, and most on the northern Pacific-Nazca boundary have migrated north; the patterns are not readily explained by the inferred distribution of mantle upwellings along the EPR axis.

  20. Promoter activity of the 5'-flanking regions of medaka fish soluble guanylate cyclase alpha1 and beta1 subunit genes.

    PubMed Central

    Yamamoto, Takehiro; Suzuki, Norio

    2002-01-01

    We examined the spatial expression pattern of medaka fish (Oryzias latipes) soluble guanylate cyclase alpha(1) and beta(1) subunit genes, OlGCS-alpha(1) and OlGCS-beta(1), and characterized the 5'-flanking region required for expression of both genes by introducing various promoter-luciferase fusion-gene constructs into COS-1 cells and medaka fish embryos. The OlGCS-alpha(1) and OlGCS-beta(1) gene transcripts were detected in whole brain and kidney in 7-day and 9-day embryos. Primer-extension analysis demonstrated that there were no differences among various adult organs (brain, eye, kidney, ovary and testis) in the transcription start site of the OlGCS-alpha(1) and OlGCS-beta(1) genes. Neither gene contained the functional TATA box within its 5'-flanking region, and the basal promoter activity was found between nucleotides +33 and +42 in the OlGCS-alpha(1) gene and between nucleotides +146 and +155 in the OlGCS-beta(1) gene. In the assay of medaka fish embryos, the 5'-flanking region of the OlGCS-beta(1) gene exhibited lower promoter activity than that of the OlGCS-alpha(1) gene. In the experiments on dual-luciferase fusion-gene constructs, the 5'-flanking region of the OlGCS-alpha(1) gene connected to the 5'-flanking region of the OlGCS-beta(1) gene was introduced into medaka fish embryos, and the 5'-flanking regions of both subunit genes were shown to mutually influence each other's promoter activity. PMID:11772405

  1. Comparison of flank margin cave development on San Salvador island, Bahamas, and Isla de Mona, Puerto Rico

    USGS Publications Warehouse

    Mylroie, J.; Carew, J.L.; Frank, E.F.; Larsen, Matthew C.

    1995-01-01

    Despite differences in rock age and geologic setting, both San Salvador and Isla do Mona show evidence of re-invasion of the flank margin caves by dissolutionally aggressive water following a vadose interval. The flank margin caves have very similar morphologies and characteristics, and the only major difference is attrutable to the larger lens size and the longer duration of stable lens position on Isla de Mona. The data indicate that dissolution occurs rapidly in these environments, and despite the development of large voids, the same geochemical environment can be re-established after an emergence episode. 

  2. Crystal morphology and thermal EMF of pyrites in the western flank of Sukholozhsky gold ore field (Lenski ore area)

    NASA Astrophysics Data System (ADS)

    Gavrilov, R.; Pshenichkin, A.; Ponamarenko, M.; Abramova, R.

    2015-11-01

    The investigated crystal morphology and thermal EMF of pyrites in the western flank of Sukholozsky ore field showed that the pyrite crystals have cubic habitus with a weakly-developed face {210}. The crystal faces {100} and {210} are covered with multiple irregular-oriented growth laminae. It has been determined that pyrites have such a property as p-type conduction and embrace insignificant thermal EMF variations. The results of the research indicated the fact of upper ore zone erosion in the western flank of Sukholozhsky ore field and its area potential at depth.

  3. Lava-flow hazard on the SE flank of Mt. Etna (Southern Italy)

    NASA Astrophysics Data System (ADS)

    Crisci, G. M.; Iovine, G.; Di Gregorio, S.; Lupiano, V.

    2008-11-01

    A method for mapping lava-flow hazard on the SE flank of Mt. Etna (Sicily, Southern Italy) by applying the Cellular Automata model SCIARA -fv is described, together with employed techniques of calibration and validation through a parallel Genetic Algorithm. The study area is partly urbanised; it has repeatedly been affected by lava flows from flank eruptions in historical time, and shows evidence of a dominant SSE-trending fracture system. Moreover, a dormant deep-seated gravitational deformation, associated with a larger volcano-tectonic phenomenon, affects the whole south-eastern flank of the volcano. The Etnean 2001 Mt. Calcarazzi lava-flow event has been selected for model calibration, while validation has been performed by considering the 2002 Linguaglossa and the 1991-93 Valle del Bove events — suitable data for back analysis being available for these recent eruptions. Quantitative evaluation of the simulations, with respect to the real events, has been performed by means of a couple of fitness functions, which consider either the areas affected by the lava flows, or areas and eruption duration. Sensitivity analyses are in progress for thoroughly evaluating the role of parameters, topographic input data, and mesh geometry on model performance; though, preliminary results have already given encouraging responses on model robustness. In order to evaluate lava-flow hazard in the study area, a regular grid of n.340 possible vents, uniformly covering the study area and located at 500 m intervals, has been hypothesised. For each vent, a statistically-significant number of simulations has been planned, by adopting combinations of durations, lava volumes, and effusion-rate functions, selected by considering available volcanological data. Performed simulations have been stored in a GIS environment for successive analyses and map elaboration. Probabilities of activation, empirically based on past behaviour of the volcano, can be assigned to each vent of the grid, by

  4. Pincer-CNC mononuclear, dinuclear and heterodinuclear Au(iii) and Pt(ii) complexes supported by mono- and poly-N-heterocyclic carbenes: synthesis and photophysical properties.

    PubMed

    Gonell, S; Poyatos, M; Peris, E

    2016-04-01

    A family of cyclometallated Au(iii) and Pt(ii) complexes containing a CNC-pincer ligand (CNC = 2,6-diphenylpyridine) supported by pyrene-based mono- or bis-NHC ligands have been synthesized and characterized, together with the preparation of a Pt-Au hetero-dimetallic complex based on a Y-shaped tris-NHC ligand. The photophysical properties of all the new species and of two related Ru(ii)-arene complexes were studied and compared. Whereas the pyrene-based complexes only exhibit emission in solution, those containing the Y-shaped tris-NHC ligand are only luminescent when dispersed in poly(methyl methacrylate) (PMMA). In particular, the pyrene-based complexes were found to be emissive in the range of 373-440 nm, with quantum yields ranging from 3.1 to 6.3%, and their emission spectra were found to be almost superimposable, pointing to the fluorescent pyrene-centered nature of the emission. This observation suggests that the emission properties of the pyrene fragment may be combined with some of the numerous applications of NHCs as supporting ligands allowing, for instance, the design of biological luminescent agents. PMID:26911885

  5. Fe[S2CNC4H8]2I: A quasi-two-dimensional XY antiferromagnet

    NASA Astrophysics Data System (ADS)

    Harlan, E. W.; Chamberlain, R. V.; DeFotis, G. C.

    1991-04-01

    The magnetic properties of Fe[S2CNC4H8]2I have been studied, the first pentacoordinate Fe(III) system of this type with a cyclic terminal group, rather than an alkyl group, to be examined in detail. The susceptibility of a polycrystalline sample is of Curie-Weiss form above 30 K, with ḡ=2.16 ±0.02 and S=3/2 and with θ=-0.75±1.0 K. Thus the unusual intermediate spin state occurs here as in earlier examples. The susceptibility can be fit quite well down to about 6 K assuming that axial and rhombic crystal field distortions occur, represented by D[Ŝ2z - S(S + 1)/3] and E[Ŝ2x - Ŝ2y] terms in the spin Hamiltonian, and incorporating exchange interactions in a mean-field approximation. Fitted parameters are D/k=9.3± 0.5 K, E/k=-0.6±0.2 K, gx=2.23± 0.05, gy= 2.19 ± 0.05, gz=2.04 ± 0.05, and zJ/k=-0.235 ±0.02 K. At low temperatures the susceptibility exhibits a broad maximum with T(χmax)=3.23± 0.04 K and χmax =0.376±0.004 emu/mol. An antiferromagnetic transition at Tc=2.21±0.01 K is inferred from the position of a maximum in (∂χ/∂T), an ordering temperature in reasonable agreement with earlier Mössbauer results. The ratio Tc/T(χmax) =0.68±0.01 is suggestive of quasi-two-dimensionality. In the region of the maximum an acceptable fit according to a 2D- XY model with plausible parameter values can be achieved, but only with a ferromagnetic interlayer exchange interaction about 28% as strong as the leading antiferromagnetic intralayer interaction. Isotherms of M vs H show somewhat unusual curvature, the explanation of which is unclear.

  6. K-Ar geochronology of basement rocks on the northern flank of the Huancabama deflection, Ecuador

    USGS Publications Warehouse

    Feininger, Tomas; Silberman, M.L.

    1982-01-01

    The Huancabamba deflection, a major Andean orocline located at the Ecuador-Peru border, constitutes an important geologic boundary on the Pacific coast of South America. Crust to the north of the deflection is oceanic and the basement is composed of basic igneous rocks of Cretaceous age, whereas crust to the south is continental and felsic rocks of Precambrian to Cretaceous age make up the basement. The northern flank of the Huancabamba Deflection in El Oro Province, Ecuador, is underlain by Precambrian polymetamorphic basic rocks of the Piedras Group; shale, siltstone, sandstone, and their metamorphosed equivalents in the Tahuin Group (in part of Devonian age); concordant syntectonic granitic rocks; quartz diorite and alaskite of the Maroabeli pluton; a protrusion of serpentinized harzburgite that contains a large inclusion of blueschist-facies metamorphic rocks, the Raspas Formation, and metamorphic rocks north of the La Palma fault. Biotite from gneiss of the Tahuin Group yields a Late Triassic K-Ar age (210 ? 8 m.y.). This is interpreted as an uplift age and is consistent with a regional metamorphism of Paleozoic age. A nearby sample from the Piedras Group that yielded a hornblende K-Ar age of 196 ? 8 m.y. was affected by the same metamorphic event. Biotite from quartz diorite of the mesozonal Maroabeli pluton yields a Late Triassic age (214 ? 6 m.y.) which is interpreted as an uplift age which may be only slightly younger than the age of magmatic crystallization. Emplacement of the pluton may postdate regional metamorphism of the Tahuin Group. Phengite from politic schist of the Raspas Formation yields an Early Cretaceous K-Ar age (132 ? 5 m.y.). This age is believed to date the isostatic rise of the encasing serpentinized harzburgite as movement along a subjacent subduction zone ceased, and it is synchronous with the age of the youngest lavas of a coeval volcanic arc in eastern Ecuador. A Late Cretaceous K-Ar age (74.4 ? 1.1 m.y.) from hornblende in

  7. Global control of merging by the interplanetary magnetic field: Cluster observations of dawnside flank magnetopause reconnection

    NASA Astrophysics Data System (ADS)

    Eriksson, S.; Elkington, S. R.; Phan, T. D.; Petrinec, S. M.; RèMe, H.; Dunlop, M. W.; Wiltberger, M.; Balogh, A.; Ergun, R. E.; André, M.

    2004-12-01

    Detailed Cluster observations of flank magnetopause reconnection are presented for two events on the Northern and the Southern Hemispheric dawnside flanks when the interplanetary magnetic field (IMF) clock angle ? = arctan(By/Bz) is within ˜45° of the equatorial plane. The event selection is based on the relative proximity between the Cluster spacecraft 1 position and the predicted magnetospheric sash where antiparallel merging is expected to develop. MHD simulations performed for the two events indicate that the Cluster spacecraft were passing through the MHD sash region in the Northern Hemisphere on 30 June 2001, while crossing the magnetopause equatorward of the Southern Hemispheric sash on 29 May 2001. Accelerated and decelerated plasma flows relative to the magnetosheath velocity were detected by Cluster on both occasions. The Walén test confirms that the observed ΔV is directly correlated with the predicted magnetic field rotation ΔB/? with the expected direction of the normal magnetic field and so we interpret them as speed changes due to magnetic reconnection. The observed directions of ΔV compare very well with the location of the simulated MHD sash relative to Cluster. The magnetic field shear in the locally tangential plane of the magnetopause ranges between 171° and 177° for the 30 June event in good agreement with antiparallel merging at the MHD sash. The corresponding local field shear for the 29 May event is only 144°, either suggesting a component merging site in the direction of the sash or indicating that Cluster is farther away from the location where the neutral line was initially formed as compared with the 30 June event. A comparison between the projected regions of antiparallel and component merging onto the magnetopause and the quasi-steady direction of plasma acceleration detected by Cluster on 29 May and 30 June support the view that the IMF controls the expected global location of magnetic reconnection at limited regions of the

  8. Efficient gusA transient expression in Porphyra yezoensis protoplasts mediated by endogenous beta-tubulin flanking sequences

    NASA Astrophysics Data System (ADS)

    Gong, Qianhong; Yu, Wengong; Dai, Jixun; Liu, Hongquan; Xu, Rifu; Guan, Huashi; Pan, Kehou

    2007-01-01

    Endogenous tubulin promoter has been widely used for expressing foreign genes in green algae, but the efficiency and feasibility of endogenous tubulin promoter in the economically important Porphyra yezoensis (Rhodophyta) are unknown. In this study, the flanking sequences of beta-tubulin gene from P. yezoensis were amplified and two transient expression vectors were constructed to determine their transcription promoting feasibility for foreign gene gusA. The testing vector pATubGUS was constructed by inserting 5'-and 3'-flanking regions ( Tub5' and Tub3') up-and down-stream of β-glucuronidase (GUS) gene ( gusA), respectively, into pA, a derivative of pCAT®3-enhancer vector. The control construct, pAGUSTub3, contains only gusA and Tub3'. These constructs were electroporated into P. yezoensis protoplasts and the GUS activities were quantitatively analyzed by spectrometry. The results demonstrated that gusA gene was efficiently expressed in P. yezoensis protoplasts under the regulation of 5'-flanking sequence of the beta-tubulin gene. More interestingly, the pATubGUS produced stronger GUS activity in P. yezoensis protoplasts when compared to the result from pBI221, in which the gusA gene was directed by a constitutive CaMV 35S promoter. The data suggest that the integration of P. yezoensis protoplast and its endogenous beta-tubulin flanking sequences is a potential novel system for foreign gene expression.

  9. Composition of pore and spring waters from Baby Bare: global implications of geochemical fluxes from a ridge flank hydrothermal system

    NASA Astrophysics Data System (ADS)

    Wheat, C. Geoffrey; Mottl, Michael J.

    2000-02-01

    Warm hydrothermal springs were discovered on Baby Bare, which is an isolated basement outcrop on 3.5 Ma-old crust on the eastern flank of the Juan de Fuca Ridge. We have sampled these spring waters from a manned submersible, along with associated sediment pore waters from 48 gravity and piston cores. Systematic variations in the chemical composition of these waters indicate that hydrothermal reactions in basement at moderate temperatures (63°C in uppermost basement at this site) remove Na, K, Li, Rb, Mg, TCO 2, alkalinity, and phosphate from the circulating seawater and leach Ca, Sr, Si, B, and Mn from the oceanic crust; and that reactions with the turbidite sediment surrounding Baby Bare remove Na, Li, Mg, Ca, Sr, and sulfate from the pore water while producing ammonium and Si and both producing and consuming phosphate, nitrate, alkalinity, Mn, and Fe. K, Rb, and B are relatively unreactive in the sediment column. These data confirm the earlier inference that sediment pore waters from areas of upwelling can be used to estimate the composition of altered seawater in the underlying basement, even for those elements that are reactive in the sediment column or are affected by sampling artifacts. The composition of altered seawater in basement at Baby Bare is similar to the inferred composition of 58°C formation water from crust nearly twice as old (5.9 Ma) on the southern flank of the Costa Rica Rift. The Baby Bare fluids also exhibit the same directions of net elemental transfer between basalt and seawater as solutions produced in laboratory experiments at a similar temperature, and complement compositional changes from seawater observed in seafloor basalts altered at cool to moderate temperatures. The common parameter among the two ridge flanks and experiments is temperature, suggesting that the residence time of seawater in basement at the two ridge-flank sites is sufficiently long for the solutions to equilibrate with altered basalt. This conclusion is supported

  10. Palagonitization of Basalt Glass in the Flanks of Mid-Ocean Ridges: Implications for the Bioenergetics of Oceanic Intracrustal Ecosystems.

    PubMed

    Türke, Andreas; Nakamura, Kentaro; Bach, Wolfgang

    2015-10-01

    When basalt is exposed to oxygenated aqueous solutions, rims of palagonite form along fractures at the expense of glass. We employed electron microprobe and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses of fresh glass and adjacent palagonite crusts to determine the geochemical changes involved in palagonite formation. Samples were retrieved from drill cores taken in the North Pond Area, located on the western flank of the Mid-Atlantic Ridge at 22°45'N and 46°05'W. We also analyzed whole rock powders to determine the overall crust-seawater exchange in a young ridge flank. Radioactive elements are enriched in palagonite relative to fresh glass, reaching concentrations where radiolytic production of molecular hydrogen (H2) may be a significant energy source. Based on these results, we hypothesize that microbial ecosystems in ridge flank habitats undergo a transition in the principal energy carrier, fueling carbon fixation from Fe oxidation in very young crust to H2 consumption in older crust. Unless the H2 is swept away by rapid fluid flow (i.e., in young flanks), it may easily accumulate to levels high enough to support chemolithoautotrophic life. In older flanks, crustal sealing and sediment accumulation have slowed down seawater circulation, and the significance of radiolytically produced H2 for catalytic energy supply is expected to increase greatly. Similar habitats on other planetary surfaces are theoretically possible, as accumulation of radiolytically produced hydrogen merely requires the presence of H2O molecules and a porous medium, from which the hydrogen is not lost. PMID:26426282

  11. Oestrogens Downregulate Tissue Factor Pathway Inhibitor through Oestrogen Response Elements in the 5’-Flanking Region

    PubMed Central

    Ali, Huda Omar; Stavik, Benedicte; Myklebust, Christiane Filion; Andersen, Elisabeth; Dahm, Anders E. A.; Iversen, Nina; Sandset, Per Morten; Skretting, Grethe

    2016-01-01

    Oestrogens influence the pathology and development of hormone-sensitive breast cancers. Tissue factor pathway inhibitor (TFPI) has been shown to be associated with breast cancer pathogenesis. Recently, we found TFPI mRNA levels to be significantly reduced by oestrogens in a breast cancer cell line (MCF7), a process mediated through the oestrogen receptor alpha (ERα). The aim of the present study was to investigate the mechanism(s) by which oestrogens may regulate TFPI at the transcriptional level. The TFPI 5’-flanking region contains three oestrogen response element (ERE) half-sites at positions -845, -769 and -50. Constructs containing the wild type or mutated ERE half-sites of the TFPI 5’-flanking region were generated in a luciferase reporter gene vector and transiently co-transfected with an ERα expression vector into HEK293 cells and subsequently treated with oestrogens. We found that luciferase activity was significantly downregulated after oestrogen stimulation in cells transfected with the wild type construct, an effect that was abolished by mutating either ERE half-sites. Electrophoretic mobility shift assay suggested direct and specific interaction of ERα with the ERE half-sites in the TFPI 5’-flanking region. Chromatin immunoprecipitation showed that ERα was recruited to the region -899 to -578 of the TFPI 5’-flanking region in vivo, where the ERE half-sites -845 and -769 are located. Our results indicate that ERα can interact with all three ERE half-sites in the TFPI 5’-flanking region and thus participate in the repression of oestrogen mediated TFPI transcription in breast cancer cells. PMID:26999742

  12. Shallow caves and blowholes on the Nullarbor Plain, Australia — Flank margin caves on a low gradient limestone platform

    NASA Astrophysics Data System (ADS)

    Burnett, Shannon; Webb, John A.; White, Susan

    2013-11-01

    The Nullarbor Plain of southern Australia is a very extensive limestone platform with relatively few large caves for its size, but contains thousands of blowholes, sub-circular vertical shafts up to 1-2 m in diameter, which often connect to similar-sized sub-horizontal passages. Recent detailed systematic surveys of large areas of the Nullarbor Plain have provided new distribution data showing that blowholes and associated shallow caves are concentrated in a 25-30 km-wide band located > 75 km inland. The known density of these features (up to 43/25 km2) underestimates the cave porosity because the strong draughts blowing from many of the blowholes indicate that they connect to extensive cave systems of small passages. These shallow caves are relict phreatic features; their entrances (blowholes) were opened as the land surface was lowered by denudation. The band of blowholes and caves is located along the Late Miocene (~ 6 Ma) shoreline across the Nullarbor, when there was a eustatic stillstand. The caves formed in the zone of enhanced dissolution at the seaward margin of the freshwater lens along the carbonate coastline, and can therefore be regarded as flank margin caves on a low gradient limestone platform; a flank margin setting relatively unknown prior to this study. The width of the band of flank margin caves, which is substantially greater than previously documented for this cave type, reflects the very low gradient of both the ground surface and water table, together with the influence of tidal fluctuations and regression of the shoreline. Flank margin cave development stopped when the sea retreated rapidly in the Late Miocene-Early Pliocene due to a period of tilting and uplift. The band of flank margin caves has high permeability and substantial porosity, and would therefore form an excellent, largely overlooked, type of palaeokarst petroleum reservoir.

  13. Modeling of Principal Flank Wear: An Empirical Approach Combining the Effect of Tool, Environment and Workpiece Hardness

    NASA Astrophysics Data System (ADS)

    Mia, Mozammel; Al Bashir, Mahmood; Dhar, Nikhil Ranjan

    2016-06-01

    Hard turning is increasingly employed in machining, lately, to replace time-consuming conventional turning followed by grinding process. An excessive amount of tool wear in hard turning is one of the main hurdles to be overcome. Many researchers have developed tool wear model, but most of them developed it for a particular work-tool-environment combination. No aggregate model is developed that can be used to predict the amount of principal flank wear for specific machining time. An empirical model of principal flank wear (VB) has been developed for the different hardness of workpiece (HRC40, HRC48 and HRC56) while turning by coated carbide insert with different configurations (SNMM and SNMG) under both dry and high pressure coolant conditions. Unlike other developed model, this model includes the use of dummy variables along with the base empirical equation to entail the effect of any changes in the input conditions on the response. The base empirical equation for principal flank wear is formulated adopting the Exponential Associate Function using the experimental results. The coefficient of dummy variable reflects the shifting of the response from one set of machining condition to another set of machining condition which is determined by simple linear regression. The independent cutting parameters (speed, rate, depth of cut) are kept constant while formulating and analyzing this model. The developed model is validated with different sets of machining responses in turning hardened medium carbon steel by coated carbide inserts. For any particular set, the model can be used to predict the amount of principal flank wear for specific machining time. Since the predicted results exhibit good resemblance with experimental data and the average percentage error is <10 %, this model can be used to predict the principal flank wear for stated conditions.

  14. Flank Sequences of miR‐145/143 and Their Aberrant Expression in Vascular Disease: Mechanism and Therapeutic Application

    PubMed Central

    Liu, Xiaojun; Cheng, Yunhui; Yang, Jian; Qin, Shanshan; Chen, Xiuwei; Tang, Xiaojun; Zhou, Xiangyu; Krall, Thomas J.; Zhang, Chunxiang

    2013-01-01

    Background Many microRNAs (miRNAs) are downregulated in proliferative vascular disease. Thus, upregulation of these miRNAs has become a major focus of research activity. However, there is a critical barrier in gene therapy to upregulate some miRNAs such as miR‐145 and miR‐143 because of their significant downregulation by the unclear endogenous mechanisms under disease conditions. The purpose of this study was to determine the molecular mechanisms responsible for their downregulation and to overcome the therapeutic barrier. Methods and Results In cultured proliferative rat vascular smooth muscle cells (VSMCs) in vitro and in diseased rat and mouse arteries in vivo, we have identified that the impairment of pri‐miR‐145 into pre‐miR‐145 is the critical step related to the downregulation of miR‐145, in which the PI3‐kinase/Akt/p53 pathway is involved. We further identified that the flank sequences of pri‐miR‐145 are the critical structural components responsible for the aberrant miR‐145 expression. Switching of the flank sequence of downregulated miR‐145 and miR‐143 to the flank sequence of miR‐31 confers resistance to their downregulation. The genetically engineered miR‐145 (smart miR‐145) restored the downregulated miR‐145 in proliferative rat VSMCs and in rat carotid arteries with balloon injury and mouse atherosclerotic aortas and demonstrated much better therapeutic effects on the abnormal growth of VSMCs, expression of its target gene, KLF5 expression, VSMC marker gene expression, and vascular neointimal growth. Conclusions The flank sequences of miR‐145 and miR‐143 play a critical role in their aberrant expression in VSMCs and vascular walls. The genetically engineered “smart” miRNAs based on their flank sequences may have broadly therapeutic applications for many vascular diseases. PMID:24166492

  15. The role of viscous magma mush spreading in volcanic flank motion at Kīlauea Volcano, Hawai‘i

    USGS Publications Warehouse

    Plattner, C.; Amelung, F.; Baker, S.; Govers, R.; Poland, M.

    2013-01-01

    Multiple mechanisms have been suggested to explain seaward motion of the south flank of Kīlauea Volcano, Hawai‘i. The consistency of flank motion during both waxing and waning magmatic activity at Kīlauea suggests that a continuously acting force, like gravity body force, plays a substantial role. Using finite element models, we test whether gravity is the principal driver of long-term motion of Kīlauea's flank. We compare our model results to geodetic data from Global Positioning System and interferometric synthetic aperture radar during a time period with few magmatic and tectonic events (2000-2003), when deformation of Kīlauea was dominated by summit subsidence and seaward motion of the south flank. We find that gravity-only models can reproduce the horizontal surface velocities if we incorporate a regional décollement fault and a deep, low-viscosity magma mush zone. To obtain quasi steady state horizontal surface velocities that explain the long-term seaward motion of the flank, we find that an additional weak zone is needed, which is an extensional rift zone above the magma mush. The spreading rate in our model is mainly controlled by the magma mush viscosity, while its density plays a less significant role. We find that a viscosity of 2.5 × 1017–2.5 × 1019 Pa s for the magma mush provides an acceptable fit to the observed horizontal surface deformation. Using high magma mush viscosities, such as 2.5 × 1019 Pa s, the deformation rates remain more steady state over longer time scales. These models explain a significant amount of the observed subsidence at Kīlauea's summit. Some of the remaining subsidence is probably a result of magma withdrawal from subsurface reservoirs

  16. Talik formation in the flank shore of water-retaining structure in permafrost area

    NASA Astrophysics Data System (ADS)

    Petrunin, A. G.; Milanovsky, S. Yu.

    2003-04-01

    Regular water and energy supply in permafrost areas are vitally important conditions for inhabitants of the large North territories of Russia, Canada, US and Alpine areas of China. Dam and flank shore stability is the key point for safety of reservoir (power pool, water supply, tailing pit, etc.). In permafrost areas stability of many engineering structures, including hydraulic work, associated with thawing- freezing process. As a result of it we can have the loss of mechanical properties causing destructive of the unit. Emergency situation of the unit we have when seepage occurs in originated permeable talik zone adjoining to reservoir. In our work we numerically analysed conditions causing origin and development of talik near reservoir builted in permafrost conditions. The results of 2D heat-mass transfer modelling indicate that the development of the talik formation strongly depends on the specific thermal and hydraulic material parameters, thickness of the layer covering talik, seasonal temperature trend and the winter snow front insulating ground rocks.

  17. Microbial Inventory of Deeply Buried Oceanic Crust from a Young Ridge Flank

    PubMed Central

    Jørgensen, Steffen L.; Zhao, Rui

    2016-01-01

    The deep marine biosphere has over the past decades been exposed as an immense habitat for microorganisms with wide-reaching implications for our understanding of life on Earth. Recent advances in knowledge concerning this biosphere have been achieved mainly through extensive microbial and geochemical studies of deep marine sediments. However, the oceanic crust buried beneath the sediments, is still largely unexplored with respect to even the most fundamental questions related to microbial life. Here, we present quantitative and qualitative data related to the microbial inventory from 33 deeply buried basaltic rocks collected at two different locations, penetrating 300 vertical meters into the upper oceanic crust on the west flank of the Mid-Atlantic spreading ridge. We use quantitative PCR and sequencing of 16S rRNA gene amplicons to estimate cell abundances and to profile the community structure. Our data suggest that the number of cells is relatively stable at ~104 per gram of rock irrespectively of sampling site and depth. Further, we show that Proteobacteria, especially Gammaproteobacteria dominate the microbial assemblage across all investigated samples, with Archaea, in general, represented by < 1% of the community. In addition, we show that the communities within the crust are distinct from the overlying sediment. However, many of their respective microbial inhabitants are shared between the two biomes, but with markedly different relative distributions. Our study provides fundamental information with respect to abundance, distribution, and identity of microorganisms in the upper oceanic crust. PMID:27303398

  18. Physical and chemical properties of submarine basaltic rocks from the submarine flanks of the Hawaiian Islands

    USGS Publications Warehouse

    Yokose, H.; Lipman, P.W.; Kanamatsu, T.

    2005-01-01

    To evaluate physical and chemical diversity in submarine basaltic rocks, approximately 280 deep submarine samples recovered by submersibles from the underwater flanks of the Hawaiian Islands were analyzed and compared. Based on observations from the submersibles and hand specimens, these samples were classified into three main occurrence types (lavas, coarse-grained volcaniclastic rocks, and fine-grained sediments), each with several subtypes. The whole-rock sulfur content and porosity in submarine basaltic rocks, recovered from depths greater than 2000 m, range from < 10 ppm and 2 vol.% to 2200 ppm and 47 vol.%, respectively. These wide variations cannot be due just to different ambient pressures at the collection depths, as inferred previously for submarine erupted lavas. The physical and chemical properties of the recovered samples, especially a combination of three whole-rock parameters (Fe-oxidation state, Sulfur content, and Porosity), are closely related to the occurrence type. The FSP triangular diagram is a valuable indicator of the source location of basaltic fragments deposited in deep submarine areas. This diagram can be applied to basaltic rocks such as clasts in debris-flow deposits, submarine-emplaced lava flows that may have crossed the shoreline, and slightly altered geological samples. ?? 2005 Elsevier B.V. All rights reserved.

  19. Mapping the fluid flow of the Mariana Mounds ridge flank hydrothermal system: Pore water chemical tracers

    NASA Astrophysics Data System (ADS)

    Wheat, C. Geoffrey; McDuff, Russell E.

    1995-01-01

    We present a conceptual model of fluid circulation in a ridge flank hydrothermal system, the Mariana Mounds. The model is based on chemical data from pore waters extracted from piston cores and from push cores collected by deep-sea research vessel Alvin in small, meter-sized mounds situated on a local topographic high. These mounds are located within a region of heat flow exceeding that calculated from a conductive model and are zones of strong pore water upflow. We have interpreted the chemical data with time-dependent transport-reaction models to estimate pore water velocities. In the mounds themselves pore water velocities reach several meters per year to kilometers per year. Within about 100 m from these zones of focused upflow velocities decrease to several centimeters per year up to tens of centimeters per year. A larger area of low heat flow surrounds these heat flow and topographic highs, with upwelling pore water velocities less than 2 cm/yr. In some nearby cores, downwelling of bottom seawater is evident but at speeds less than 2 cm/yr. Downwelling through the sediments appears to be a minor source of seawater recharge to the basaltic basement. We conclude that the principal source of seawater recharge to basement is where basement outcrops exist, most likely a scarp about 2-4 km to the east and southeast of the study area.

  20. Volcanic and seismic activity at Stromboli preceding the 2002-2003 flank eruption

    NASA Astrophysics Data System (ADS)

    Burton, M.; Calvari, S.; Spampinato, L.; Lodato, L.; Pino, N. A.; Marchetti, E.; Murè, F.

    Regular surveys with a thermal camera from both ground- and helicopter-based surveys have been carried out on Stromboli since October 2001. This data set allowed us to detect morphological changes in Stromboli's summit craters produced by major explosions and to track an increase in volcanic activity associated with a heightened magma level within the main conduit that preceded the 2002-2003 effusive eruption. Together with thermal measurements, geophysical surveys performed in May and September/October 2002 highlighted clear increases in the amplitude of very long period (VLP) events, consistent with the ascent of the magma column above the VLP source region. The increased magma level was probably induced by elevated pressure in the deep feeding system, controlled by regional tectonic stress. This, in turn, pressurized the uppermost part of the crater terrace, producing greater soil permeability and soil degassing. Eventually, the magma loading caused the NW flank of the summit craters to fracture, allowing lava to flood out at high effusion rates on 28 December 2002, starting an approximately 6-month-long effusive eruption.

  1. Influence of Transcontinental arch on Cretaceous listric-normal faulting, west flank, Denver basin

    SciTech Connect

    Davis, T.L.

    1983-08-01

    Seismic studies along the west flank of the Denver basin near Boulder and Greeley, Colorado illustrate the interrelationship between shallow listric-normal faulting in the Cretaceous and deeper basement-controlled faulting. Deeper fault systems, primarily associated with the Transcontinental arch, control the styles and causative mechanisms of listric-normal faulting that developed in the Cretaceous. Three major stratigraphic levels of listric-normal faulting occur in the Boulder-Greeley area. These tectonic sensitive intervals are present in the following Cretaceous formations: Laramie-Fox Hills-upper Pierre, middle Pierre Hygiene zone, and the Niobrara-Carlile-Greenhorn. Documentation of the listric-normal fault style reveals a Wattenberg high, a horst block or positive feature of the greater Transcontinental arch, was active in the east Boulder-Greeley area during Cretaceous time. Paleotectonic events associated with the Wattenberg high are traced through analysis of the listric-normal fault systems that occur in the area. These styles are important to recognize because of their stratigraphic and structural influence on Cretaceous petroleum reservoir systems in the Denver basin. Similar styles of listric-normal faulting occur in the Cretaceous in many Rocky Mountain foreland basins.

  2. Petrology of parasitic and eccentric cones on the flanks and base of Somma-Vesuvius

    NASA Astrophysics Data System (ADS)

    Macdonald, Ray; Bagiński, Bogusław; Rolandi, Giuseppe; De Vivo, Benedetto; Kopczyńska, Anna

    2016-02-01

    Parasitic and eccentric cones on the flanks and at the base of Somma-Vesuvius potentially provide information on the plumbing system of the complex. We present geochemical data for minerals, glasses and rocks from the Pollena and Cercola cones. The rocks are phonotephrites and a basaltic trachyandesite. A volumetrically dominant type contains phenocrysts of olivine, clinopyroxene, leucite, plagioclase ± apatite ± Fe-Ti-oxides. A second type is phlogopite-phyric. Low magnesium-numbers (62-49) and Ni abundances (≤32 ppm) indicate that the primary magmas underwent crustal-level fractionation but the cores of olivine and clinopyroxene phenocrysts carry records of the parental magmas. Geochemical data indicate that the rocks form more than one magmatic lineage. Matrix glasses point to low-pressure fractionation trends towards decreasing melt silica-undersaturation. The phlogopite-phyric rocks were derived from more hydrous magmas than those lacking phlogopite phenocrysts, perhaps at higher pressures. Phenocryst assemblages are difficult to reconcile with published experimental work and it is likely that they are far from equilibrium assemblages. The cone magmas were probably derived from high levels within the main plumbing system via lateral transport.

  3. Episodic slow slip events and seaward flank motion at Mt. Etna volcano (Italy)

    NASA Astrophysics Data System (ADS)

    Palano, Mimmo

    2016-09-01

    Episodic aseismic slip events have recently been detected at a variety of tectonic and volcanic environments, sparking the curiosity of seismic and geodetic communities. Here, a sequence of 7 slow slip events occurring at Mt. Etna since mid-2009 has been analyzed. Observed displacement fields evidence that the sequence involves two contiguous sectors of the unstable eastern flank, delimited by the Timpe faults. The tectonic control played by these faults can also be recognized on the long-term (2003-2015) velocity field. Elastic modelling of the long-term velocity field infers a sub-horizontal plane slightly dipping eastward and located within the sedimentary basement at shallow depth. Slip distribution models for each slow-slip event highlight how the largest slip values were centred on the SE edge of the sub-horizontal plane during 4 events and on the NE edge during the remaining 3 ones. The recognized events do not appear correlated with volcanic activity, although there is a possible correlation between slow-slip events and inflating episodes of the volcano.

  4. Soft sediment deformation structures in the Maastrichtian Ajali Formation Western Flank of Anambra Basin, Southern Nigeria

    NASA Astrophysics Data System (ADS)

    Olabode, Solomon Ojo

    2014-01-01

    Soft sediment deformation structures were recognized in the Maastrichtian shallow marine wave to tide influenced regressive sediments of Ajali Formation in the western flank of Anambra basin, southern Nigerian. The soft sediment deformation structures were in association with cross bedded sands, clay and silt and show different morphological types. Two main types recognised are plastic deformations represented by different types of recumbent folds and injection structure represented by clastic dykes. Other structures in association with the plastic deformation structures include distorted convolute lamination, subsidence lobes, pillars, cusps and sand balls. These structures are interpreted to have been formed by liquefaction and fluidization mechanisms. The driving forces inferred include gravitational instabilities and hydraulic processes. Facies analysis, detailed morphologic study of the soft sediment deformation structures and previous tectonic history of the basin indicate that the main trigger agent for deformation is earthquake shock. The soft sediment deformation structures recognised in the western part of Anambra basin provide a continuous record of the tectonic processes that acted on the regressive Ajali Formation during the Maastrichtian.

  5. Active maize genes are unmodified and flanked by diverse classes of modified, highly repetitive DNA.

    PubMed

    Bennetzen, J L; Schrick, K; Springer, P S; Brown, W E; SanMiguel, P

    1994-08-01

    We have characterized the copy number, organization, and genomic modification of DNA sequences within and flanking several maize genes. We found that highly repetitive DNA sequences were tightly linked to most of these genes. The highly repetitive sequences were not found within the coding regions but could be found within 6 kb either 3' or 5' to the structural genes. These highly repetitive regions were each composed of unique combinations of different short repetitive sequences. Highly repetitive DNA blocks were not interrupted by any detected single copy DNA. The 13 classes of highly repetitive DNA identified were found to vary little between diverse Zea isolates. The level of DNA methylation in and near these genes was determined by scoring the digestibility of 63 recognition/cleavage sites with restriction enzymes that were sensitive to 5-methylation of cytosines in the sequences 5'-CG-3' and 5'-CNG-3'. All but four of these sites were digestible in chromosomal DNA. The four undigested sites were localized to extragenic DNA within or near highly repetitive DNA, while the other 59 sites were in low copy number DNAs. Pulsed field gel analysis indicated that the majority of cytosine modified tracts range from 20 to 200 kb in size. Single copy sequences hybridized to the unmodified domains, while highly repetitive sequences hybridized to the modified regions. Middle repetitive sequences were found in both domains. PMID:7958822

  6. Seismic detection of a low-velocity layer beneath the southeast flank of Mauna Loa, Hawaii

    SciTech Connect

    Thurber, C.H.; Li, Yingping ); Johnson, C.

    1989-07-01

    The authors have identified seismic phases reflected off the top and bottom of a low velocity layer (LVL) by analysis of seismograms from six small earthquakes in Hawaii. These events occurred almost directly beneath station AIN of the Hawaiian Volcano Observatory (HVO) seismic network, located within the Kaoiki seismic zone on the southeast flank of Mauna Loa. The polarity reversals of the first reflected phases provide clear evidence for the existence of a LVL beneath this station. The LVL is estimated to be at a depth of about 11.5 km, with a thickness of about 800 m. The estimated depth to the top of the LVL is consistent with the depth distribution of low-angle thrust faulting events from the aftershock sequence of the 1983 Kaoiki earthquake. Presumably, this zone is the marine sediment layer buried beneath the volcanic pile, along which the volcanic edifice may slip easily to cause large earthquakes. Mapping the interface between the volcanic pile and oceanic crust and thus determining the depth and thickness of the buried sediment layer is essential for understanding the tectonics of large earthquakes in Hawaii.

  7. CD8+ T cell epitope-flanking mutations disrupt proteasomal processing of HIV-1 Nef.

    PubMed

    Milicic, Anita; Price, David A; Zimbwa, Peter; Booth, Bruce L; Brown, Helen L; Easterbrook, Philippa J; Olsen, Kara; Robinson, Nicola; Gileadi, Uzi; Sewell, Andrew K; Cerundolo, Vincenzo; Phillips, Rodney E

    2005-10-01

    CTL play a critical role in the control of HIV and SIV. However, intrinsic genetic instability enables these immunodeficiency viruses to evade detection by CTL through mutation of targeted antigenic sites. These mutations can impair binding of viral epitopes to the presenting MHC class I molecule or disrupt TCR-mediated recognition. In certain regions of the virus, functional constraints are likely to limit the capacity for variation within epitopes. Mutations elsewhere in the protein, however, might still enable immune escape through effects on Ag processing. In this study, we describe the coincident emergence of three mutations in a highly conserved region of Nef during primary HIV-1 infection. These mutations (R69K, A81G, and H87R) flank the HLA B*35-restricted VY8 epitope and persisted to fixation as the early CTL response to this Ag waned. The variant form of Nef showed a reduced capacity to activate VY8-specific CTL, although protein stability and expression levels were unchanged. This effect was associated with altered processing by the proteasome that caused partial destruction of the VY8 epitope. Our data demonstrate that a variant HIV genotype can significantly impair proteasomal epitope processing and substantiate the concept of immune evasion through diminished Ag generation. These observations also indicate that the scale of viral escape may be significantly underestimated if only intraepitope variation is evaluated. PMID:16177107

  8. FAST TRACK PAPER: Evaluation of elastodynamic interferometric redatuming: a synthetic study on salt dome flank imaging

    NASA Astrophysics Data System (ADS)

    Lu, Rongrong; Willis, Mark E.; Campman, Xander H.; Toksöz, M. Nafi

    2009-03-01

    The recent introduction of novel redatuming techniques, based on the principles of time-reversed acoustics and source-receiver reciprocity, has allowed seismic measurements collected on one datum to be extrapolated to another datum. Under favourable conditions, this process can approximately remove the complicated overburden structures without any velocity information. We introduce an elastic redatuming scheme for walkaway vertical seismic profiles (WVSPs) based on these principles, using P- and S-wave potentials, which are derived from the spatial derivatives of the measured wavefields. Additional field acquisition is utilized to directly measure these derivatives. We test our elastic redatuming scheme on data simulated with an elastic finite difference algorithm. The elastodynamic Green's functions between multicomponent receivers in a borehole are then extracted from data recorded using multicomponent (P- and S-wave) sources at the surface. The wavefields are redatumed as four parts: two related to the P-wave potential, and another two related to the S-wave potential. These parts are migrated separately and form four independent images of the salt dome flank, providing a more complete elastic description of the subsurface.

  9. Spatial Distribution of Rolled up Kelvin-Helmholtz Vortices at Earth's Dayside and Flank Magnetopause

    NASA Technical Reports Server (NTRS)

    Taylor, M. G. G. T.; Hasegawa, H.; Lavraud, B.; Phan, T.; Escoubet, C. P.; Dunlop, M. W.; Bogdanova, Y. V.; Borg, A. L.; Volwerk, M.; Berchem, J.; Constantinescu, O. D.; Eastwood, J. P.; Masson, A.; Laakso, H.; Soucek, J.; Fazakerley, A. N.; Frey, H. U.; Panov, E. V.; Shen, C.; Shi, J. K.; Sibeck, D. G.; Pu, Z. Y.; Wang, J.; Wild, J. A.

    2012-01-01

    The Kelvin-Helmholtz Instability (KHI) can drive waves at the magnetopause. These waves can grow to form rolled-up vortices and facilitate transfer of plasma into the magnetosphere. To investigate the persistence and frequency of such waves at the magnetopause we have carried out a survey of all Double Star 1 magnetopause crossings, using a combination of ion and magnetic field measurements. Using criteria originally used in a Geotail study made by Hasegawa et al. (2006) (forthwith referred to as H2006), 17 candidate events were identified from the entire TC-1 mission (covering 623 orbits where the magnetopause was sampled), a majority of which were on the dayside of the terminator. The relationship between density and shear velocity was then investigated, to identify the predicted signature of a rolled up vortex from H2006 and all 17 events exhibited some level of rolled up behavior. The location of the events had a clear dawn-dusk asymmetry, with 12 (71 %) on the post noon, dusk flank suggesting preferential growth in this region.

  10. Canonical Azimuthal Rotations and Flanking Residues Constrain the Orientation of Transmembrane Helices

    PubMed Central

    Sánchez-Muñoz, Orlando L.; Strandberg, Erik; Esteban-Martín, E.; Grage, Stephan L.; Ulrich, Anne S.; Salgado, Jesús

    2013-01-01

    In biological membranes the alignment of embedded proteins provides crucial structural information. The transmembrane (TM) parts have well-defined secondary structures, in most cases α-helices and their orientation is given by a tilt angle and an azimuthal rotation angle around the main axis. The tilt angle is readily visualized and has been found to be functionally relevant. However, there exist no general concepts on the corresponding azimuthal rotation. Here, we show that TM helices prefer discrete rotation angles. They arise from a combination of intrinsic properties of the helix geometry plus the influence of the position and type of flanking residues at both ends of the hydrophobic core. The helical geometry gives rise to canonical azimuthal angles for which the side chains of residues from the two ends of the TM helix tend to have maximum or minimum immersion within the membrane. This affects the preferential position of residues that fall near hydrophobic/polar interfaces of the membrane, depending on their hydrophobicity and capacity to form specific anchoring interactions. On this basis, we can explain the orientation and dynamics of TM helices and make accurate predictions, which correspond well to the experimental values of several model peptides (including dimers), and TM segments of polytopic membrane proteins. PMID:23561527

  11. Mapping the fluid flow of the Mariana Mounds ridge flank hydrothermal system: Pore water chemical tracers

    SciTech Connect

    Wheat, C.G.; McDuff, R.E.

    1995-05-10

    The authors present a conceptual model of fluid circulation in a ridge flank hydrothermal system, the Mariana Mounds. The model is based on chemical data from pore waters extracted from piston cores and from push cores collected by deep-sea research vessel Alvin in small, meter-sized mounds situated on a local topographic high. These mounds are located within a region of heat flow exceeding that calculated from a conductive model and are zones of strong pore water upflow. The authors have interpreted the chemical data with time-dependent transport-reaction models to estimate pore water velocities. In the mounds themselves pore water velocities reach several meters per year to kilometers per year. Within about 100 m from these zones of focused upflow velocities decrease to several centimeters per year up to tens of centimeters per year. A large area of low heat flow surrounds these heat flow and topographic highs, with upwelling pore water velocities less than 2 cm/yr. In some nearby cores, downwelling of bottom seawater is evident but at speeds less than 2 cm/yr. Downwelling through the sediments appears to be a minor source of seawater recharge to the basaltic basement. The authors conclude that the principal source of seawater recharge to basement is where basement outcrops exist, most likely a scarpt about 2-4 km to the east and southeast of the study area. 71 refs., 14 figs., 3 tabs.

  12. Nodes of Ranvier act as barriers to restrict invasion of flanking paranodal domains in myelinated axons.

    PubMed

    Thaxton, Courtney; Pillai, Anilkumar M; Pribisko, Alaine L; Dupree, Jeffrey L; Bhat, Manzoor A

    2011-01-27

    Accumulation of voltage-gated sodium (Na(v)) channels at nodes of Ranvier is paramount for action potential propagation along myelinated fibers, yet the mechanisms governing nodal development, organization, and stabilization remain unresolved. Here, we report that genetic ablation of the neuron-specific isoform of Neurofascin (Nfasc(NF¹⁸⁶)) in vivo results in nodal disorganization, including loss of Na(v) channel and ankyrin-G (AnkG) enrichment at nodes in the peripheral nervous system (PNS) and central nervous system (CNS). Interestingly, the presence of paranodal domains failed to rescue nodal organization in the PNS and the CNS. Most importantly, using ultrastructural analysis, we demonstrate that the paranodal domains invade the nodal space in Nfasc(NF¹⁸⁶) mutant axons and occlude node formation. Our results suggest that Nfasc(NF¹⁸⁶)-dependent assembly of the nodal complex acts as a molecular boundary to restrict the movement of flanking paranodal domains into the nodal area, thereby facilitating the stereotypic axonal domain organization and saltatory conduction along myelinated axons. PMID:21262464

  13. Novel microbial assemblages inhabiting crustal fluids within mid-ocean ridge flank subsurface basalt.

    PubMed

    Jungbluth, Sean P; Bowers, Robert M; Lin, Huei-Ting; Cowen, James P; Rappé, Michael S

    2016-08-01

    Although little is known regarding microbial life within our planet's rock-hosted deep subseafloor biosphere, boreholes drilled through deep ocean sediment and into the underlying basaltic crust provide invaluable windows of access that have been used previously to document the presence of microorganisms within fluids percolating through the deep ocean crust. In this study, the analysis of 1.7 million small subunit ribosomal RNA genes amplified and sequenced from marine sediment, bottom seawater and basalt-hosted deep subseafloor fluids that span multiple years and locations on the Juan de Fuca Ridge flank was used to quantitatively delineate a subseafloor microbiome comprised of distinct bacteria and archaea. Hot, anoxic crustal fluids tapped by newly installed seafloor sampling observatories at boreholes U1362A and U1362B contained abundant bacterial lineages of phylogenetically unique Nitrospirae, Aminicenantes, Calescamantes and Chloroflexi. Although less abundant, the domain Archaea was dominated by unique, uncultivated lineages of marine benthic group E, the Terrestrial Hot Spring Crenarchaeotic Group, the Bathyarchaeota and relatives of cultivated, sulfate-reducing Archaeoglobi. Consistent with recent geochemical measurements and bioenergetic predictions, the potential importance of methane cycling and sulfate reduction were imprinted within the basalt-hosted deep subseafloor crustal fluid microbial community. This unique window of access to the deep ocean subsurface basement reveals a microbial landscape that exhibits previously undetected spatial heterogeneity. PMID:26872042

  14. ConservedPrimers 2.0: A high-throughput pipeline for comparative genome referenced intron-flanking PCR primer design and its application in wheat SNP discovery

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In some genomic applications it is necessary to design large numbers of PCR primers in exons flanking one or several introns on the basis of orthologous gene sequences in related species. The primer pairs designed by this target gene approach are called "intron-flanking primers" or because they ar...

  15. Distribution of contact loads over the flank-land of the cutter with a rounded cutting edge

    NASA Astrophysics Data System (ADS)

    Kozlov, V.; Gerasimov, A.; Kim, A.

    2016-04-01

    In this paper, contact conditions between a tool and a workpiece material for wear-simulating turning by a cutter with a sharp-cornered edge and with a rounded cutting edge are analysed. The results of the experimental study of specific contact load distribution over the artificial flank wear-land of the cutter in free orthogonal turning of the disk from titanium alloy (Ti6Al2Mo2Cr), ductile (63Cu) and brittle (57Cu1Al3Mn) brasses are described. Investigations were carried out by the method of ‘split cutter’ and by the method of the artificial flank-land of variable width. The experiments with a variable feed rate and a cutting speed show that in titanium alloy machining with a sharp-cornered cutting edge the highest normal contact load (σh max = 3400…2200 MPa) is observed immediately at the cutting edge, and the curve has a horizontal region with the length of 0.2… 0.6 mm. At a distance from the cutting edge, the value of specific normal contact load is dramatically reduced to 1100…500 MPa. The character of normal contact load for a rounded cutting edge is different -it is uniform, and its value is approximately 2 times smaller compared to machining with a sharp-cornered cutting edge. In author’s opinion it is connected with generation of a seizure zone in a chip formation region and explains the capacity of highly worn-out cutting tools for titanium alloys machining. The paper analyses the distribution of tangential contact loads over the flank land, which pattern differs considerably for machining with a sharp-cornered edge and with a rounded cutting edge. Abbreviation and symbols: m/s - meter per second (cutting speed v); mm/r - millimeter per revolution (feed rate f); MPa - mega Pascal (specific contact load as a stress σ or τ) hf - the width of the flank wear land (chamfer) of the cutting tool, flank wear land can be natural or artificial like the one in this paper [mm]; xh - distance from the cutting edge on the surface of the flank-land [mm

  16. Catastrophic flank collapses and slumping in Pico Island during the last 130 kyr (Pico-Faial ridge, Azores Triple Junction)

    NASA Astrophysics Data System (ADS)

    Costa, A. C. G.; Hildenbrand, A.; Marques, F. O.; Sibrant, A. L. R.; Santos de Campos, A.

    2015-09-01

    The Pico Island constitutes the easternmost sub-aerial domain of a steep WNW-ESE volcanic ridge, which has developed within the Nubia-Eurasia diffuse plate boundary (Azores Triple Junction). The island comprises three volcanic systems, from older to younger: the Topo Volcano, the Fissural System, and the Pico Stratovolcano. From a high-resolution Digital Elevation Model (10 m), and new bathymetric, stratigraphic, structural, and high-precision K-Ar data, we reconstruct the main successive stages of growth and partial destruction of the island over the last 200 kyr. We especially concentrate on the central sector of the island, which has recorded gradual movements through slumping and catastrophic flank collapses since ca. 130 kyr. The remmants of the Topo Volcano are partly exposed on Pico's SE flank, and are here dated between 186 ± 5 and 115 ± 4 ka. Topo was significantly destroyed by N- and S-directed large-scale flank collapses between ca. 125 and 70 ka. On Pico's N flank, collapse seems to have removed all the unstable material, but in the S the collapse structure is composite, including a major flank collapse and a remnant slump complex that is still active. A first episode of deformation occurred between ca. 125 and 115 ka along the master fault of the slump. Between ca. 115 and 69 ka, most of the unstable material was removed by a major flank collapse, leaving behind a still considerable volume of unstable material that comprises the active slump. This first collapse was catastrophic and generated a large debris deposit recognized on the high-resolution bathymetry, with a minimum run-out of ca. 17 km. The scar was partially filled by volcanic products erupted from volcanic cones developed within the slump depression, and possibly also from the early WNW-ESE Fissural System. Subsequent deformation in the slump area affected in part the filling units, leading to the individualization of secondary curved faults. Younger volcanic products have gradually

  17. Flank Deformation Recorded during Cotopaxís Awakening in 2015

    NASA Astrophysics Data System (ADS)

    Mothes, Patricia A.; Nocquet, Jean-Mathieu; Yépez, Marco A.; Jarrín, Paúl A.; Ruiz, Mario C.; Gaunt, Elizabeth

    2016-04-01

    Cotopaxi, a large glacier-topped stratocone in the Ecuadorian Andes begin to display anomalous seismic activity in April, 2015 when the IGEPŃs 15 station seismic network registered an increase in long period seismic events which were located 3-12 km below the crater. Several weeks later a distinct inflationary pattern was observed at the VC1 tilt station, 6 km NE of the crater, where we recorded a steady ascent of 150 urads (daily rate 3.2 urads) through 01 June. The tilt rate tended to slow and displayed a start & stop tilt pattern through 01 August, when a strong positive trend again resumed. Subsequently, a strong positive tilt pattern was predominante and briefly stalled after the occurrence of 5 small explosions/strong emissions on 14 August, 2015. About September 1st and prior to the onset of a high-energy VT seismic swarm, a rapid onset of strong positive tilt is observed. Subsequently, even though 30-100 VT events were registered daily, the tilt pattern leveled off in November to December, presumably because the events were with magnitudes <1 and that the magma supply was waning? Five other tilt stations on the volcano are much less sensitive than the VC1 station and this probably reflects the ideal coupling of the VC1 tiltmeter to a thick lava flow, which descends from the summit. The seven station GPS network displayed a strong displacement to the NW-SW for the stations on the W-SW flanks and had accumulative horizontal changes of 1 cm with a maximum vertical displacement of 1 cm at stations on the S and E. The trends of stations on the NE flank, with their movement purely to the north and east are difficult to interpret, but may be related to a preferential movement upon an old avalanche scar surface and water lubrication. While the changes detected by GPS are small, they did increase through time and finally, like the tilt, leveled off in November, 2015. We believe that these pattern are the result of small batches of magma ascending up the conduit and

  18. Sedimentological and geochemical characterization of the Cretaceous strata of Calabar Flank, southeastern Nigeria

    NASA Astrophysics Data System (ADS)

    Boboye, O. A.; Okon, E. E.

    2014-11-01

    An integrated sedimentological and geochemical evaluation has been carried out on the Cretaceous sediments of the Calabar Flank. This study is to characterize the provenance, depositional environments and hydrocarbon potentials. The techniques involved field descriptions, textural parameters, petrographic analysis and biostratigraphic studies using standard sedimentological methods. The geochemical studies involved the determination of major oxides and trace elements using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS); Total Organic Carbon (TOC) and Rock Eval Pyrolysis. Results show that sandstone from Awi Formation have elongation ratio ranging from 0.4b to 0.9, oblate-prolate index and maximum sphericity index range from 9.6 to 9.7 and 0.5 to 0.9 respectively. The sandstone units are arkosic and mineralogically immature (MI = 3); ZTR indexes range from 54.6% to 82.5%, with tourmaline, zircon, staurolite, garnet, apatite, augite and rutile grains being angular-sub-angular. This suggests nearness to source, and that Awi Formation was deposited in a fluvial environment. The limestone deposit of Mfamosing Formation is predominantly bioclastic consisting of algal stromatolites, oolitic and pelloidal grainstones/packstones with high carbonate content. The dark grey fissile shales of Nkporo and Ekenkpon Formations indicate deposition in quiet oxic and/or anoxic conditions. Average TOC suggests good source rocks. Predominance of Type III kerogen, Tmax and hydrocarbon source potential of Mfamosing, Ekenkpon, New Netim Marl and Nkporo Formations suggest marginal mature to mature source rocks deposited in shallow continental to open marine setting that some gas may have been generated. The sediments are derived from passive continental margin in plutonic humid palaeoclimatic setting of continental block province.

  19. Regions flanking exon 1 regulate constitutive expression of the human antithrombin gene.

    PubMed

    Fernandez-Rachubinski, F A; Weiner, J H; Blajchman, M A

    1996-11-15

    We have identified cis-acting elements and trans-acting factors that regulate constitutive expression of the human antithrombin gene. The activity of the sequences flanking the first exon of the gene was investigated using a luciferase-based reporter assay in transiently transfected HepG2, COS1, BSC40, and HeLa cells. Deletion analysis allowed the mapping of two elements able to promote antithrombin gene transcription in HepG2 and COS1 cells. The first element is located upstream of the first exon (-150/+68 nucleotides). The second element is in the first intervening sequence (+300/+700 nucleotides) and functions in an orientation opposite to that of the first. Footprint analysis showed three protected areas in the 5' upstream element at -92/-68 (element A), -14/+37 (element B), and -126/-100 nucleotides (element C). These elements acted as enhancers in luciferase reporter assays. Gel retardation analysis demonstrated that two liver-enriched transcription factors, hepatocyte nuclear factor 4 (HNF4) and CCAAT enhancer-binding protein (C/EBPa), bound to the 5' upstream element. HNF4 bound to elements A and C, whereas C/EBPa bound to element B. Element A also interacted with the ubiquitous nuclear hormone receptors chicken ovalbumin upstream promoter transcription factor 1 (COUP-TF1), thyroid hormone receptor alpha (TRalpha), peroxisome proliferator-activated receptor alpha(PPARalpha), and retinoid X receptor alpha (RXRalpha). In HepG2 and BSC40 cells, HNF4, C/EBPalpha, and RXRalpha activated luciferase expression from a reporter construct containing the 5'-upstream minimal antithrombin gene promoter, while COUP-TF1, TRalpha, and HNF3 (alpha or beta) repressed such expression. Our results show that constitutive expression of the human antithrombin gene depends in part upon the interplay of these transcription factors and suggest that signaling pathways regulated by these factors can modulate antithrombin gene transcription. PMID:8910619

  20. Seismic Anisotropy Beneath the Eastern Flank of the Rio Grande Rift

    NASA Astrophysics Data System (ADS)

    Benton, N. W.; Pulliam, J.

    2015-12-01

    Shear wave splitting was measured across the eastern flank of the Rio Grande Rift (RGR) to investigate mechanisms of upper mantle anisotropy. Earthquakes recorded at epicentral distances of 90°-130° from EarthScope Transportable Array (TA) and SIEDCAR (SC) broadband seismic stations were examined comprehensively, via the Matlab program "Splitlab", to determine whether SKS and SKKS phases indicated anisotropic properties. Splitlab allows waveforms to be rotated, filtered, and windowed interactively and splitting measurements are made on a user-specified waveform segment via three independent methods simultaneously. To improve signal-to-noise and improve reliability, we stacked the error surfaces that resulted from grid searches in the measurements for each station location. Fast polarization directions near the Rio Grande Rift tend to be sub-parallel to the RGR but then change to angles that are consistent with North America's average plate motion, to the east. The surface erosional depression of the Pecos Valley coincides with fast polarization directions that are aligned in a more northerly direction than their neighbors, whereas the topographic high to the east coincides with an easterly change of the fast axis.The area above a mantle high velocity anomaly discovered separately via seismic tomography which may indicate thickened lithosphere, corresponds to unusually large delay times and fast polarization directions that are more closely aligned to a north-south orientation. The area of southeastern New Mexico that falls between the mantle fast anomaly and the Great Plains craton displays dramatically smaller delay times, as well as changes in fast axis directions toward the northeast. Changes in fast axis directions may indicate flow around the mantle anomaly; small delay times could indicate vertical or attenuated flow.

  1. Toward a unified physical model of nucleosome patterns flanking transcription start sites

    PubMed Central

    Möbius, Wolfram; Osberg, Brendan; Tsankov, Alexander M.; Rando, Oliver J.; Gerland, Ulrich

    2013-01-01

    Recent genome-wide maps of nucleosome positions in different eukaryotes revealed patterns around transcription start sites featuring a nucleosome-free region flanked by a periodic modulation of the nucleosome density. For Saccharomyces cerevisiae, the average in vivo pattern was previously shown to be quantitatively described by a “nucleosome gas” model based on the statistical positioning mechanism. However, this simple physical description is challenged by the fact that the pattern differs quantitatively between species and by recent experiments that appear incompatible with statistical positioning, indicating important roles for chromatin remodelers. We undertake a data-driven search for a unified physical model to describe the nucleosome patterns of 12 yeast species and also consider an extension of the model to capture remodeling effects. We are led to a nucleosome gas that takes into account nucleosome breathing, i.e., transient unwrapping of nucleosomal DNA segments. This known biophysical property of nucleosomes rationalizes a “pressure”-induced dependence of the effective nucleosome size that is suggested by the data. By fitting this model to the data, we find an average energy cost for DNA unwrapping consistent with previous biophysical experiments. Although the available data are not sufficient to reconstruct chromatin remodeling mechanisms, a minimal model extension by one mechanism yields an “active nucleosome gas” that can rationalize the behavior of systems with reduced histone–DNA ratio and remodeler knockouts. We therefore establish a basis for a physical description of nucleosome patterns that can serve as a null model for sequence-specific effects at individual genes and in models of transcription regulation. PMID:23509245

  2. Spatiotemporal gravity variations to look deep into the southern flank of Etna volcano

    NASA Astrophysics Data System (ADS)

    Greco, Filippo; Currenti, Gilda; Del Negro, Ciro; Napoli, Rosalba; Budetta, Gennaro; Fedi, Maurizio; Boschi, Enzo

    2010-11-01

    A 14-year-long microgravity data set (October 1994 to September 2007) collected along a 24-km east-west trending profile of 19 stations was analyzed to detect underground mass redistributions related to the volcanic activity involving the southern flank of Mt Etna (Italy). A multiresolution wavelet analysis was applied to separate the volcano-related anomalies from the unwanted components. The residual image having both spatial extension and temporal duration evidenced two complete gravity increase/decrease cycles mainly affecting the central and eastern stations of the profile. The first gravity increase (early 1995 to the end of 1996) and decrease (end of 1996 to late in 1998) cycle reached a maximum amplitude of approximately 90 μGal. The second gravity increase (mid-1999 to mid-2000) and decrease (mid-2000 to early-2004) cycle attained an amplitude of about 80 μGal. After about 5 years of a persistent negative gravity anomaly, a new semicycle started at the end of 2006 and continued during the last survey carried out in September 2007. The density changes, modeled over time since 1994 using a Quadratic Programming algorithm, are mainly located at a depth of 2-4 km bsl in a region recognized to be a preferential pathway of magma rising and an intermediate zone of magma storage/withdrawal. The computed positive mass variations of about 105 × 109 kg were interpreted as magma accumulation, while negative mass changes of about -120 × 109 kg were associated with either magma drainage or opening of new voids by tectonic stresses within a source volume, where tensional earthquakes occurred.

  3. Temperature and Redox Effect on Mineral Colonization in Juan de Fuca Ridge Flank Subsurface Crustal Fluids

    PubMed Central

    Baquiran, Jean-Paul M.; Ramírez, Gustavo A.; Haddad, Amanda G.; Toner, Brandy M.; Hulme, Samuel; Wheat, Charles G.; Edwards, Katrina J.; Orcutt, Beth N.

    2016-01-01

    To examine microbe-mineral interactions in subsurface oceanic crust, we evaluated microbial colonization on crustal minerals that were incubated in borehole fluids for 1 year at the seafloor wellhead of a crustal borehole observatory (IODP Hole U1301A, Juan de Fuca Ridge flank) as compared to an experiment that was not exposed to subsurface crustal fluids (at nearby IODP Hole U1301B). In comparison to previous studies at these same sites, this approach allowed assessment of the effects of temperature, fluid chemistry, and/or mineralogy on colonization patterns of different mineral substrates, and an opportunity to verify the approach of deploying colonization experiments at an observatory wellhead at the seafloor instead of within the borehole. The Hole U1301B deployment did not have biofilm growth, based on microscopy and DNA extraction, thereby confirming the integrity of the colonization design against bottom seawater intrusion. In contrast, the Hole U1301A deployment supported biofilms dominated by Epsilonproteobacteria (43.5% of 370 16S rRNA gene clone sequences) and Gammaproteobacteria (29.3%). Sequence analysis revealed overlap in microbial communities between different minerals incubated at the Hole U1301A wellhead, indicating that mineralogy did not separate biofilm structure within the 1-year colonization experiment. Differences in the Hole U1301A wellhead biofilm community composition relative to previous studies from within the borehole using similar mineral substrates suggest that temperature and the diffusion of dissolved oxygen through plastic components influenced the mineral colonization experiments positioned at the wellhead. This highlights the capacity of low abundance crustal fluid taxa to rapidly establish communities on diverse mineral substrates under changing environmental conditions such as from temperature and oxygen. PMID:27064928

  4. Effects of topically applied antiandrogenic compounds on sebaceous glands of hamster ears and flank organs

    SciTech Connect

    Schroeder, H.G.Z.; Ziegler, M.; Nickisch, K.; Kaufmann, J.; el Etreby, M.F.

    1989-05-01

    Growth of sebaceous glands in the ears and flank organs of castrated male hamsters is dependent on androgen substitution. Taking this for granted, a study was done to compare the effects of topical antiandrogenic treatment in vivo on the morphology and size of sebaceous glands with the concomitant changes in in vitro metabolism of /sup 3/H-testosterone. The role of dihydrotestosterone in sebaceous gland stimulation was thereby investigated. Topical treatment was carried out with the androgen antagonist 17 alpha-propylmesterolone (PM), with 4-androsten-3-one-17 beta-carboxylic acid (17 beta-C), and 17 beta-N,N-diethylcarbamoyl-4-methyl-4-aza-5 alpha-androstan-3-one (4-MA), both described as specific 4-steroid-5 alpha-reductase inhibitors, and with progesterone (PRO), which is an androgen receptor antagonist with 5 alpha-reductase inhibiting properties. Regrowth of sebaceous glands after castration and substitution with testosterone propionate or dihydrotestosterone could be inhibited by topical PM and PRO. This occurred irrespective of the influence on testosterone metabolism and irrespective of the mode of substitution. 4-MA, on the other hand, while exhibiting strong 5 alpha-reductase inhibition in vitro, was ineffective in reducing sebaceous gland sizes in vivo. The compound 17 beta-C was ineffective in every respect. In no case were systemic antiandrogenic effects on prostates and seminal vesicles observed. Our results support the view that the DHT formation rate has no regulatory function for growth of sebaceous glands in hamsters and that PM and PRO counteract the androgenic stimulus by their competitive antagonistic binding to the androgen receptor, but not by their influence on testosterone metabolism.

  5. Integrated geophysical and hydrothermal models of flank degassing and fluid flow at Masaya Volcano, Nicaragua

    USGS Publications Warehouse

    Sanford, Ward E.; Pearson, S.C.P.; Kiyosugi, K.; Lehto, H.L.; Saballos, J.A.; Connor, C.B.

    2012-01-01

    We investigate geologic controls on circulation in the shallow hydrothermal system of Masaya volcano, Nicaragua, and their relationship to surface diffuse degassing. On a local scale (~250 m), relatively impermeable normal faults dipping at ~60° control the flowpath of water vapor and other gases in the vadose zone. These shallow normal faults are identified by modeling of a NE-SW trending magnetic anomaly of up to 2300 nT that corresponds to a topographic offset. Elevated SP and CO2 to the NW of the faults and an absence of CO2 to the SE suggest that these faults are barriers to flow. TOUGH2 numerical models of fluid circulation show enhanced flow through the footwalls of the faults, and corresponding increased mass flow and temperature at the surface (diffuse degassing zones). On a larger scale, TOUGH2 modeling suggests that groundwater convection may be occurring in a 3-4 km radial fracture zone transecting the entire flank of the volcano. Hot water rising uniformly into the base of the model at 1 x 10-5 kg/m2s results in convection that focuses heat and fluid and can explain the three distinct diffuse degassing zones distributed along the fracture. Our data and models suggest that the unusually active surface degassing zones at Masaya volcano can result purely from uniform heat and fluid flux at depth that is complicated by groundwater convection and permeability variations in the upper few km. Therefore isolating the effects of subsurface geology is vital when trying to interpret diffuse degassing in light of volcanic activity.

  6. LEF-1 recognition of platinated GG sequences within double-stranded DNA. Influence of flanking bases.

    PubMed

    Chválová, Katerina; Sari, Marie-Agnès; Bombard, Sophie; Kozelka, Jirí

    2008-02-01

    The lymphoid enhancer-binding factor 1 (LEF-1) recognizes a double-stranded 9 base-pairs (bp) long motif in DNA which is significantly bent upon binding. This bend is centered at two destacked adenines whose geometry closely resembles that of two adjacent guanines crosslinked by the antitumor drug cisplatin. It has been proposed that cisplatin-GG crosslinks could hijack high mobility group (HMG) box containing transcription factors such as LEF-1. In order to examine such a possibility, we used electrophoretic mobility shift assays to determine the affinity of the HMG box of LEF-1 for a series of 25 oligonucleotides containing a central GG sequence, free or site-specifically modified by cisplatin. The binding affinity of the GG-platinated oligonucleotides was 3-6-fold higher than that determined for the corresponding unplatinated oligonucleotides, however, the binding to all cisplatin-modified oligonucleotides was at least 1 order of magnitude weaker than that to the 25 bp oligonucleotide containing the recognition 9 bp motif. The binding affinity was dependent on the nature of bases flanking the cisplatin-crosslinked G(*)G(*) dinucleotide, the AG(*)G(*)T sequence displaying the strongest affinity and CG(*)G(*)T showing the strongest binding enhancement upon platination. In contrast, modification of the AGGT sequence with the third-generation platinum antitumor drug oxaliplatin did not enhance the affinity significantly. These results suggest that the cisplatin-caused bending of DNA does produce a target for LEF-1 binding, however, the cisplatinated DNA does not appear to be a strong competitor for the LEF-1 recognition sequence. PMID:17961652

  7. Clay mineral burial diagenesis: A case study from the Calabar flank of the Niger Delta

    NASA Astrophysics Data System (ADS)

    Braide, Sokari P.

    Detailed clay mineralogic and chemical analyses of Tertiary subsurface sediments of the Agbada and Akata Formations, from two wells on the Calabar Flank of the Niger Delta, have been systematically studied with a view to understanding clay mineral burial diagenesis. Five principal clay minerals, smectite, illite, kaolinite, chlorite and various proportions of mixed-layer illite/smectite were identified. Seven major oxides (SiO 2, Al 2O 3, MgO, Fe 2O 3, CaO, Na 2O, K 2O) were analysed for with an atomic absorption spectrophotometer, with a view to ascertain any depth related variations. The geothermal gradient of the two wells (Uruan-1 and Uda-1) was also calculated. The results appear to suggest a transformation from smectite to a mixed-layer illite/smectite (I/S) phase. The transformation first goes to a random I/S phase, and then to ordered I/S and back to random I/S, even though postulated conditions for a complete transformation to illite did exist. It would therefore seem, from this case study, that neither temperature nor the availability of potassium is the principal factor controlling the transformation. Kaolinite and chlorite distribution does not exhibit any systematic trend that could be related to burial diagenesis. These results provoked an extensive literature review on the subject, and key ideas discerned are summarized here. The prognosis? In the author's opinion, we still have a lot to learn about the factors that control the mechanics and reaction extent of clay mineral burial diagenesis.

  8. The phylogenetic utility and functional constraint of microRNA flanking sequences

    PubMed Central

    Kenny, Nathan J.; Sin, Yung Wa; Hayward, Alexander; Paps, Jordi; Chu, Ka Hou; Hui, Jerome H. L.

    2015-01-01

    MicroRNAs (miRNAs) have recently risen to prominence as novel factors responsible for post-transcriptional regulation of gene expression. miRNA genes have been posited as highly conserved in the clades in which they exist. Consequently, miRNAs have been used as rare genome change characters to estimate phylogeny by tracking their gain and loss. However, their short length (21–23 bp) has limited their perceived utility in sequenced-based phylogenetic inference. Here, using reference taxa with established phylogenetic relationships, we demonstrate that miRNA sequences are of high utility in quantitative, rather than in qualitative, phylogenetic analysis. The clear orthology among miRNA genes from different species makes it straightforward to identify and align these sequences from even fragmentary datasets. We also identify significant sequence conservation in the regions directly flanking miRNA genes, and show that this too is of utility in phylogenetic analysis, as well as highlighting conserved regions that will be of interest to other fields. Employing miRNA sequences from 12 sequenced drosophilid genomes, together with a Tribolium castaneum outgroup, we demonstrate that this approach is robust using Bayesian and maximum-likelihood methods. The utility of these characters is further demonstrated in the rhabditid nematodes and primates. As next-generation sequencing makes it more cost-effective to sequence genomes and small RNA libraries, this methodology provides an alternative data source for phylogenetic analysis. The approach allows rapid resolution of relationships between both closely related and rapidly evolving species, and provides an additional tool for investigation of relationships within the tree of life. PMID:25694624

  9. Temperature and Redox Effect on Mineral Colonization in Juan de Fuca Ridge Flank Subsurface Crustal Fluids.

    PubMed

    Baquiran, Jean-Paul M; Ramírez, Gustavo A; Haddad, Amanda G; Toner, Brandy M; Hulme, Samuel; Wheat, Charles G; Edwards, Katrina J; Orcutt, Beth N

    2016-01-01

    To examine microbe-mineral interactions in subsurface oceanic crust, we evaluated microbial colonization on crustal minerals that were incubated in borehole fluids for 1 year at the seafloor wellhead of a crustal borehole observatory (IODP Hole U1301A, Juan de Fuca Ridge flank) as compared to an experiment that was not exposed to subsurface crustal fluids (at nearby IODP Hole U1301B). In comparison to previous studies at these same sites, this approach allowed assessment of the effects of temperature, fluid chemistry, and/or mineralogy on colonization patterns of different mineral substrates, and an opportunity to verify the approach of deploying colonization experiments at an observatory wellhead at the seafloor instead of within the borehole. The Hole U1301B deployment did not have biofilm growth, based on microscopy and DNA extraction, thereby confirming the integrity of the colonization design against bottom seawater intrusion. In contrast, the Hole U1301A deployment supported biofilms dominated by Epsilonproteobacteria (43.5% of 370 16S rRNA gene clone sequences) and Gammaproteobacteria (29.3%). Sequence analysis revealed overlap in microbial communities between different minerals incubated at the Hole U1301A wellhead, indicating that mineralogy did not separate biofilm structure within the 1-year colonization experiment. Differences in the Hole U1301A wellhead biofilm community composition relative to previous studies from within the borehole using similar mineral substrates suggest that temperature and the diffusion of dissolved oxygen through plastic components influenced the mineral colonization experiments positioned at the wellhead. This highlights the capacity of low abundance crustal fluid taxa to rapidly establish communities on diverse mineral substrates under changing environmental conditions such as from temperature and oxygen. PMID:27064928

  10. A Coarse-Grained Model for Polyglutamine Aggregation Modulated by Amphipathic Flanking Sequences

    PubMed Central

    Ruff, Kiersten M.; Khan, Siddique J.; Pappu, Rohit V.

    2014-01-01

    The aggregation of proteins with expanded polyglutamine (polyQ) tracts is directly relevant to the formation of neuronal intranuclear inclusions in Huntington’s disease. In vitro studies have uncovered the effects of flanking sequences as modulators of the driving forces and mechanisms of polyQ aggregation in sequence segments associated with HD. Specifically, a seventeen-residue amphipathic stretch (N17) that is directly N-terminal to the polyQ tract in huntingtin decreases the overall solubility, destabilizes nonfibrillar aggregates, and accelerates fibril formation. Published results from atomistic simulations showed that the N17 module reduces the frequency of intermolecular association. Our reanalysis of these simulation results demonstrates that the N17 module also reduces interchain entanglements between polyQ domains. These two effects, which are observed on the smallest lengthscales, are incorporated into phenomenological pair potentials and used in coarse-grained Brownian dynamics simulations to investigate their impact on large-scale aggregation. We analyze the results from Brownian dynamics simulations using the framework of diffusion-limited cluster aggregation. When entanglements prevail, which is true in the absence of N17, small spherical clusters and large linear aggregates form on distinct timescales, in accord with in vitro experiments. Conversely, when entanglements are quenched and a barrier to intermolecular associations is introduced, both of which are attributable to N17, the timescales for forming small species and large linear aggregates become similar. Therefore, the combination of a reduction of interchain entanglements through homopolymeric polyQ and barriers to intermolecular associations appears to be sufficient for providing a minimalist phenomenological rationalization of in vitro observations regarding the effects of N17 on polyQ aggregation. PMID:25185558

  11. Regulation of alpha o expression by the 5'-flanking region of the alpha o gene.

    PubMed

    Li, Y; Mortensen, R; Neer, E J

    1994-11-01

    Many responses of cells to external signals require activation of the heterotrimeric G proteins. These responses depend on the type and amount of G proteins that are expressed. Each cell has a characteristic complement of G protein subunits. For example, the alpha o subunit is very abundant in neural tissues. Very little is known about the mechanisms that determine cellular levels of G proteins. In the present study, we have isolated a genomic clone for mouse alpha o gene and identified the promoter region. There are multiple transcription initiation sites located about 750 base pairs upstream of the translational start site. The promoter region is GC-rich and contains neither a TATA-box nor a CAAT box. Transient expression assays using a series of constructs containing various lengths of the 5'-flanking region of the alpha o promoter demonstrated that the region 300-700 base pairs upstream of the transcription initiation sites is responsible for the basic promoter activity. The relative activity of alpha o promoter is 8-12-fold higher in cells expressing alpha o than in cells lacking alpha o. The level of alpha o in cells may also be regulated at the level of protein translation because deletions in the 5'-noncoding region of alpha o gene increase reporter enzyme expression without a corresponding increase in reporter enzyme mRNA level. Our results suggest that both transcriptional and post-transcriptional mechanisms are involved in regulating the expression of alpha o in vivo. Transcriptional regulation probably is important for control of tissue-specific expression, while posttranscriptional mechanisms may be used to regulate the alpha o level in cells. PMID:7961675

  12. Dissolved organic carbon in ridge-axis and ridge-flank hydrothermal systems

    NASA Astrophysics Data System (ADS)

    Lang, Susan Q.; Butterfield, David A.; Lilley, Marvin D.; Paul Johnson, H.; Hedges, John I.

    2006-08-01

    The circulation of hydrothermal fluid through the upper oceanic crustal reservoir has a large impact on the chemistry of seawater, yet the impact on dissolved organic carbon (DOC) in the ocean has received almost no attention. To determine whether hydrothermal circulation is a source or a sink for DOC in the oceans, we measured DOC concentrations in hydrothermal fluids from several environments. Hydrothermal fluids were collected from high-temperature vents and diffuse, low-temperature vents on the basalt-hosted Juan de Fuca Ridge axis and also from low-temperature vents on the sedimented eastern flanks. High-temperature fluids from Main Endeavour Field (MEF) and Axial Volcano (AV) contain very low DOC concentrations (average = 15 and 17 μM, respectively) compared to background seawater (36 μM). At MEF and AV, average DOC concentrations in diffuse fluids (47 and 48 μM, respectively) were elevated over background seawater, and high DOC is correlated with high microbial cell counts in diffuse fluids. Fluids from off-axis hydrothermal systems located on 3.5-Ma-old crust at Baby Bare Seamount and Ocean Drilling Program (ODP) Hole 1026B had average DOC concentrations of 11 and 13 μM, respectively, and lowered DOC was correlated with low cell counts. The relative importance of heterotrophic uptake, abiotic sorption to mineral surfaces, thermal decomposition, and microbial production in fixing the DOC concentration in vent fluids remains uncertain. We calculated the potential effect of hydrothermal circulation on the deep-sea DOC cycle using our concentration data and published water flux estimates. Maximum calculated fluxes of DOC are minor compared to most oceanic DOC source and sink terms.

  13. Deletions flanked by breakpoints 3 and 4 on 15q13 may contribute to abnormal phenotypes

    PubMed Central

    Rosenfeld, Jill A; Stephens, Lindsey E; Coppinger, Justine; Ballif, Blake C; Hoo, Joe J; French, Beatrice N; Banks, Valerie C; Smith, Wendy E; Manchester, David; Tsai, Anne Chun-Hui; Merrion, Katrina; Mendoza-Londono, Roberto; Dupuis, Lucie; Schultz, Roger; Torchia, Beth; Sahoo, Trilochan; Bejjani, Bassem; Weaver, David D; Shaffer, Lisa G

    2011-01-01

    Non-allelic homologous recombination (NAHR) between segmental duplications in proximal chromosome 15q breakpoint (BP) regions can lead to microdeletions and microduplications. Several individuals with deletions flanked by BP3 and BP4 on 15q13, immediately distal to, and not including the Prader–Willi/Angelman syndrome (PW/AS) critical region and proximal to the BP4–BP5 15q13.3 microdeletion syndrome region, have been reported; however, because the deletion has also been found in normal relatives, the significance of these alterations is unclear. We have identified six individuals with deletions limited to the BP3–BP4 interval and an additional four individuals with deletions of the BP3–BP5 interval from 34 046 samples submitted for clinical testing by microarray-based comparative genomic hybridization (aCGH). Of four individuals with BP3–BP4 deletions for whom parental testing was conducted, two were apparently de novo and two were maternally inherited. A comparison of clinical features, available for five individuals in our study (four with deletions within BP3–BP4 and one with a BP3-BP5 deletion), with those in the literature show common features of short stature and/or failure to thrive, microcephaly, hypotonia, and premature breast development in some individuals. Although the BP3–BP4 deletion does not yet demonstrate statistically significant enrichment in abnormal populations compared with control populations, the presence of common clinical features among probands and the presence of genes with roles in development and nervous system function in the deletion region suggest that this deletion may have a role in abnormal phenotypes in some individuals. PMID:21248749

  14. Tectonic development of the SW Arabian Plate margin within the central Arabian flank of the Red Sea rift system

    NASA Astrophysics Data System (ADS)

    Szymanski, E.; Stockli, D. F.; Johnson, P. R.; Kattan, F. H.; Cosca, M. A.

    2009-12-01

    The Red Sea rift system is a prime example of continental rifting and has contributed significantly to our understanding of the geologic processes that manage the rupture of continental lithosphere. Using a combined geo- and thermochronometric approach, we explore the modes and mechanisms of rift margin development by studying Red Sea rift-related geologic products along the central Saudi Arabian flank of the rift system, north of Jeddah. We use apatite and zircon (U-Th)/He thermochronometry and whole-rock 40Ar/39Ar dating of basalt to define the spatiotemporal relationship between rift flank extensional structures and rift-related harrat volcanism. This technical approach permits the reconstruction of the tectonic margin from early rift architecture, to strain distribution during progressive rifting, and through subsequent whole-scale modifications of the rift flank due to thermal and isostatic factors. Constraints on the dynamics of rift flank deformation are achieved through the collection of geologic samples along long-baseline thermochronometric transects that traverse the entire Arabian shield from the coastal escarpment to the inland Paleozoic sedimentary cover sequences. Long-baseline transects resolve the timing of rift flank uplift and reveal the pattern of lithospheric modification during the rupturing of continental lithosphere. Locally, short-baseline elevation transects map the footwall exhumation of major normal faults that delineate both the modern rift margin and inland extensional basins such as the NW-trending Hamd-Jizil basin, a prominent syn-extensional basin comprised of two distinct half-grabens (Jizil and Hamd) located NW of Medina. Diffuse lithospheric extension during the Oligo-Miocene affected a widespread area well inboard from the modern rift margin; samples from footwall blocks that bound the inland Jizil and Hamd half-grabens yield apatite (U-Th)/He cooling ages of 14.7 ± 0.9 Ma and 24.5 ± 1.5 Ma, respectively. The mid-Miocene age

  15. Flanking sequence determination and event specific detection of transgenic wheat B72-8-11b strain.

    PubMed

    Zhang, Piqiao; Xu, Junyi; Zheng, Qiuyue; Luan, Fengxia; Cao, Jijuan; Hou, Hesheng

    2013-03-01

    Exogenous fragment sequence and flanking sequence between exogenous fragment and recombinant chromosome of transgenic wheat B72-8-11b were successfully acquired through PCR amplification with cross-matched primers from exogenous genes. Newly acquired exogenous fragment covered the full-length sequence of transformed genes such as transformed plasmid and corresponding functional genes including marker uidA, promoter ubiquitin, lacZ, 1Dx5, and part of sequence of the wheat genome. A specific PCR detection method for transgenic wheat B72-8-11b strain was established on the basis of primers designed according to flanking sequence. The designed primers revealed specific amplification of 132 bp product of transgenic wheat B72-8-11b strain. This method is characteristics of high specificity, high reproducibility, rapid identification, and excellent accuracy for the identification of transgenic wheat B72-8-11b strain. PMID:23319185

  16. A new colorful species of Pristimantis (Anura: Craugastoridae) from the eastern flank of the Cordillera Central in Colombia .

    PubMed

    Rivera-Prieto, Diego A; Rivera-Correa, Mauricio; Daza, Juan M

    2014-01-01

    We describe a new species of Pristimantis from the humid forests on the eastern flank of the northern Cordillera Central in Colombia (6º 23' 19.3554" N, 75º 1' 24.0594" W; ca. 1150 m.a.s.l.). Pristimantis jaguensis sp. nov. is characterized by an extraordinary variation in color and is readily distinguished from congeneric species by lacking nuptial pads, discoidal fold and conical calcar tubercles; flanks and belly white to cream without blotches as well as iris yellow ocher to copper with thick brown reticulation and cream sclera. Molecular phylogenetic analyses recovered the new species in a clade with species mostly distributed in Ecuador. Our finding suggests that new taxa can still be discovered in the Middle Magdalena River valley of Colombia despite the extensive sampling this region has received during the last decades.  PMID:25543734

  17. Preliminary assessment of the state of CO2 soil degassing on the flanks of Gede volcano (West Java, Indonesia)

    NASA Astrophysics Data System (ADS)

    Kunrat, S. L.; Schwandner, F. M.

    2013-12-01

    Gede Volcano (West Java) is part of an andesitic stratovolcano complex consisting of Pangrango in the north-west and Gede in the south-east. The last recorded eruptive activity was a phreatic subvolcanian ash eruption in 1957. Current activity is characterized by episodic swarms at 2-4 km depth, and low-temperature (~160°C) crater degassing in two distinct summit crater fumarolic areas. Hot springs occur in the saddle between the Gede and Pangrango edifice, as well as on the NE flank base. The most recent eruptive events produced pyroclastic material, their flow deposits concentrate toward the NE. A collaborative effort between the Center for Volcanology and Geological Hazard Mitigation (CVGHM), Geological Agency and the Earth Observatory of Singapore (EOS) is since 2010 aimed at upgrading the geophysical and geochemical monitoring network at Gede Volcano. To support the monitoring instrumentation upgrades under way, surveys of soil CO2 degassing have been performed on the flanks of Gede, in circular and radial traverses.The goal was to establish a spatial distribution of flank CO2 fluxes, and to allow smart siting for continuous gas monitoring stations. Crater fluxes were not surveyed, as its low-temperature hydrothermal system is likely prone to large hydraulic changes in this tropical environment, resulting in variable permeability effects that might mask signals from deeper reservoir or conduit degassing. The high precipitation intensity in the mountains of tropical Java pose challenges to this method, since soil gas permeability is largely controlled by soil moisture content. Simultaneous soil moisture measurements were undertaken. The soil CO2 surveys were carried out using a LI-8100A campaign flux chamber instrument (LICOR Biosciences, Lincoln, Nebraska). This instrument has a very precise and highly stable sensor and an atmospheric pressure equilibrator, making it highly sensitive to low fluxes. It is the far superior choice for higher precision low

  18. Caveats of the Tsyganenko-Sitnov magnetic field models at distances beyond 10 RE in the flanks

    NASA Astrophysics Data System (ADS)

    Klida, M. M.; Fritz, T. A.

    2009-12-01

    The Tsyganenko and Tsyganenko-Sitnov magnetic field models are used extensively in the magneto-spheric modeling community. These empirically based models use measurements from an extensive list of satellites to modify the earth’s dipole field in response to the contact with the solar wind. Because these models are empirically based, their strengths lie in regions of the magnetosphere where the most satellite measurements are made. The outer flanks of magnetosphere near the terminator are regions of transition between the compressed dayside and the stretched tail. Contour maps of total field strength along with fully three dimensional particle tracings are used to examine the Tsyganenko-Sitnov interpretation of the magnetic field in the flanks. When ions and electrons are traced through these regions, unrealistic paths can occur. As a result, caution must be exercised in the aforementioned regions when using these models, as unrealistic magnetic field topologies, and consequently unrealistic particle trajectories, may arise.

  19. Novel Oversampling Technique for Improving Signal-to-Quantization Noise Ratio on Accelerometer-Based Smart Jerk Sensors in CNC Applications

    PubMed Central

    Rangel-Magdaleno, Jose J.; Romero-Troncoso, Rene J.; Osornio-Rios, Roque A.; Cabal-Yepez, Eduardo

    2009-01-01

    Jerk monitoring, defined as the first derivative of acceleration, has become a major issue in computerized numeric controlled (CNC) machines. Several works highlight the necessity of measuring jerk in a reliable way for improving production processes. Nowadays, the computation of jerk is done by finite differences of the acceleration signal, computed at the Nyquist rate, which leads to low signal-to-quantization noise ratio (SQNR) during the estimation. The novelty of this work is the development of a smart sensor for jerk monitoring from a standard accelerometer, which has improved SQNR. The proposal is based on oversampling techniques that give a better estimation of jerk than that produced by a Nyquist-rate differentiator. Simulations and experimental results are presented to show the overall methodology performance. PMID:22412337

  20. Effects of altered 5'-flanking sequences on the in vivo expression of a Saccharomyces cerevisiae tRNATyr gene.

    PubMed Central

    Shaw, K J; Olson, M V

    1984-01-01

    Deletion mutations ending in the 5'-flanking sequences of the Saccharomyces cerevisiae SUP4-o gene have been analyzed for their effects on gene expression. This ochre-suppressing tRNATyr gene was cloned into a S. cerevisiae centromeric plasmid, and its level of in vivo expression was monitored by observing the suppressor phenotype of the gene after transformation into S. cerevisiae. A deletion mutant that retains only four base pairs of the 5'-flanking sequence is profoundly deficient in expression; deletion mutants extending to positions -18, -17, -16, or -15 are moderately deficient; deletion mutants extending to positions -36 or -27 are slightly defective; and mutants retaining more than 60 base pairs of the original 5'-flanking DNA are expressed normally. In some cases, the cloning procedure led to the introduction of multiple BamHI linkers at the SUP4-o-vector fusion site, and in one instance, the resulting structure dramatically affects gene function: the presence of three linkers abutting a -18 deletion completely inhibits the in vivo expression of SUP4-o. In contrast, three linkers that abut a -77 deletion have no effect on in vivo expression. The template properties of these plasmids in a homologous in vitro transcription system parallel the levels of in vivo expression, suggesting that the mutations predominantly affect transcription. The data demonstrate that there are significant functional constraints on the 5'-flanking sequences of this RNA polymerase III-transcribed gene. The dramatic effects of the multiple linker insertion at position -18 suggest that there may be extensive melting of the DNA in this region during normal transcription initiation. Images PMID:6371493

  1. Uplift and denudation history of the eastern Dead Sea rift flank, SW Jordan: Evidence from apatite fission track thermochronometry

    NASA Astrophysics Data System (ADS)

    Feinstein, S.; Eyal, M.; Kohn, B. P.; Steckler, M. S.; Ibrahim, K. M.; Moh'd, B. K.; Tian, Y.

    2013-09-01

    Dead Sea rift (DSR), developed along the Dead Sea transform plate boundary, is characterized by salient flanks and morphotectonic asymmetry. Apatite fission track thermochronology (AFT) along ~1200 m high vertical profiles in Neoproterozoic basement and overlying Cambrian sandstone in southwestern Jordan is used to reconstruct timing, magnitude, and rate of uplift and denudation of the eastern DSR flank and examine its relationship to rift development and its flank landscape. Time-temperature models based on AFT data suggest three major Phanerozoic heating and cooling episodes, Late Paleozoic, Early Cretaceous, and Oligocene. The latest episode, on which this study focuses, indicates uplift of ~3.8±0.3 km under a moderate paleogeothermal gradient. About 40% of the uplift was tectonically driven with the remainder attributed to isostatic rebound in response to denudation and erosion. Models suggest that uplift commenced in the Oligocene with a considerable part occurring prior to development of the DSR, despite being ~200 km from the Red Sea-Gulf of Suez rift margin. Uplift is probably part of a regional rearrangement along the western Arabian platform margin occurring at the time of Red Sea rift initiation. Transition from primarily sedimentary layer stripping, most likely by scarp retreat, to one of dominantly incision of the underlying crystalline basement occurred in Late Miocene-Pliocene time following enhanced subsidence and development of a low base level in the DSR. Consequently, the magnitude of uplift by isostatic rebound due to incision exceeded lowering by surface truncation and increased summit elevation and riftward flexing of the flank.

  2. Sheared sheet intrusions as mechanism for lateral flank displacement on basaltic volcanoes: Applications to Réunion Island volcanoes

    NASA Astrophysics Data System (ADS)

    Cayol, V.; Catry, T.; Michon, L.; Chaput, M.; Famin, V.; Bodart, O.; Froger, J.-L.; Romagnoli, C.

    2014-10-01

    Field work carried out on the Piton des Neiges volcano (Réunion Island) suggests that the injection of magma along detachments could trigger flank failure by conjugate opening and shear displacement. We use 3-D numerical models to compare the ability of purely opened sheet intrusions, sheared sheet intrusions, and normal faults to induce flank displacement on basaltic volcanoes. We assume that shear stress change on fractures results from stress anisotropy of the host rock under gravity. Exploring a large range of stress anisotropies, fracture dips, and fracture depth over length ratios, we determine that the amount of shear displacement is independent of the proximity to the ground surface. Sheared sheet intrusions are the most efficient slip medium on volcanoes. Consequently, the largest flank displacement is induced by the longest, deepest sheared intrusion dipping closest to 45° in a host rock with the highest stress anisotropy. Using our model in a forward way, we provide shear and normal displacements for buried fractures. Applying the model to a pile of sills at the Piton des Neiges volcano, we determine that the mean shear displacement caused by each intrusion was 3.7 m, leading to a total of a 180-260 m of lateral displacement for the 50 m high pile of sills. Using our model in an inverse way, we formulate a decision tree to determine some fracture characteristics and the host rock stress anisotropy from ratios of maximum surface displacements. This procedure provides a priori models, which can be used to bound the parameter space before it is explored through a formal inversion. Applying the decision tree to the 1.4 m coeruptive flank displacement recorded at Piton de la Fournaise in 2007, we find that it probably originated from a shallow eastward dipping subhorizontal normal fault.

  3. Polyglutamine Amyloid Core Boundaries and Flanking Domain Dynamics in Huntingtin Fragment Fibrils Determined by Solid-State Nuclear Magnetic Resonance

    PubMed Central

    2015-01-01

    In Huntington’s disease, expansion of a polyglutamine (polyQ) domain in the huntingtin (htt) protein leads to misfolding and aggregation. There is much interest in the molecular features that distinguish monomeric, oligomeric, and fibrillar species that populate the aggregation pathway and likely differ in cytotoxicity. The mechanism and rate of aggregation are greatly affected by the domains flanking the polyQ segment within exon 1 of htt. A “protective” C-terminal proline-rich flanking domain inhibits aggregation by inducing polyproline II structure (PPII) within an extended portion of polyQ. The N-terminal flanking segment (httNT) adopts an α-helical structure as it drives aggregation, helps stabilize oligomers and fibrils, and is seemingly integral to their supramolecular assembly. Via solid-state nuclear magnetic resonance (ssNMR), we probe how, in the mature fibrils, the htt flanking domains impact the polyQ domain and in particular the localization of the β-structured amyloid core. Using residue-specific and uniformly labeled samples, we find that the amyloid core occupies most of the polyQ domain but ends just prior to the prolines. We probe the structural and dynamical features of the remarkably abrupt β-sheet to PPII transition and discuss the potential connections to certain htt-binding proteins. We also examine the httNT α-helix outside the polyQ amyloid core. Despite its presumed structural and demonstrated stabilizing roles in the fibrils, quantitative ssNMR measurements of residue-specific dynamics show that it undergoes distinct solvent-coupled motion. This dynamical feature seems reminiscent of molten-globule-like α-helix-rich features attributed to the nonfibrillar oligomeric species of various amyloidogenic proteins. PMID:25280367

  4. Flank creeping, a mechanism of stabilisation and destabilisation: example of the Tenerife NE-Rift Zone, Spain

    NASA Astrophysics Data System (ADS)

    Delcamp, A.; van Wyk de Vries, B.; Troll, V.; Petronis, M. S.; Carracedo, J. C.

    2009-12-01

    The volcanic evolution of Tenerife has been largely studied, and the eruptive story of the NE and NW rift zones is now well-constrained. A systematic and detailed mapping of dykes of the North East Rift Zone (NERZ) allows to go further and brings new highlights in the intrusive story related to the three successive collapses (1-Micheque, 2-Guïmar and 3-La Orotava) that are located on each side of the rift. Flank creeping seems to be the major mechanism that accommodates the emplacement of the intrusive complex and its associated dykes. Flank spreading allows the stabilisation of the rift until a critical point where further intrusion will generate collapse. The main features deduced from field observation are reproduced and confirmed using analogue models consisting in plaster-sand ridges intruded by golden syrup. The rift at its first stages of growth may be controlled by the regional stress field but its future development depends on the local stress field created by the rift zone evolution. Volcanic rift zones represent clearly a dynamic and changing geological and geographical environment. Keywords: rift zone, flank creeping, strike-slip, dyke intrusion, basal intrusive complex, collapse.

  5. Flanking sequence determination and event-specific detection of genetically modified wheat B73-6-1.

    PubMed

    Xu, Junyi; Cao, Jijuan; Cao, Dongmei; Zhao, Tongtong; Huang, Xin; Zhang, Piqiao; Luan, Fengxia

    2013-05-01

    In order to establish a specific identification method for genetically modified (GM) wheat, exogenous insert DNA and flanking sequence between exogenous fragment and recombinant chromosome of GM wheat B73-6-1 were successfully acquired by means of conventional polymerase chain reaction (PCR) and thermal asymmetric interlaced (TAIL)-PCR strategies. Newly acquired exogenous fragment covered the full-length sequence of transformed genes such as transformed plasmid and corresponding functional genes including marker uidA, herbicide-resistant bar, ubiquitin promoter, and high-molecular-weight gluten subunit. The flanking sequence between insert DNA revealed high similarity with Triticum turgidum A gene (GenBank: AY494981.1). A specific PCR detection method for GM wheat B73-6-1 was established on the basis of primers designed according to the flanking sequence. This specific PCR method was validated by GM wheat, GM corn, GM soybean, GM rice, and non-GM wheat. The specifically amplified target band was observed only in GM wheat B73-6-1. This method is of high specificity, high reproducibility, rapid identification, and excellent accuracy for the identification of GM wheat B73-6-1. PMID:23449073

  6. Ups and downs on spreading flanks of ocean-island volcanoes: evidence from Mauna Loa and Kīlauea

    USGS Publications Warehouse

    Lipman, Peter W.; Eakins, Barry W.; Yokose, Hisayoshi

    2003-01-01

    Submarine-flank deposits of Hawaiian volcanoes are widely recognized to have formed largely by gravitationally driven volcano spreading and associated landsliding. Observations from submersibles show that prominent benches at middepths on flanks of Mauna Loa and Kilauea consist of volcaniclastic debris derived by landsliding from nearby shallow submarine and subaerial flanks of the same edifice. Massive slide breccias from the mature subaerial tholeiitic shield of Mauna Loa underlie the frontal scarp of its South Kona bench. In contrast, coarse volcaniclastic sediments derived largely from submarine-erupted preshield alkalic and transitional basalts of ancestral Kilauea underlie its Hilina bench. Both midslope benches record the same general processes of slope failure, followed by modest compression during continued volcano spreading, even though they record development during different stages of edifice growth. The dive results suggest that volcaniclastic rocks at the north end of the Kona bench, interpreted by others as distal sediments from older volcanoes that were offscraped, uplifted, and accreted to the island by far-traveled thrusts, alternatively are a largely coherent stratigraphic assemblage deposited in a basin behind the South Kona bench.

  7. Comparison of properties of small-scale ion flux fluctuations in the flank magnetosheath and in the solar wind

    NASA Astrophysics Data System (ADS)

    Riazantseva, M. O.; Budaev, V. P.; Rakhmanova, L. S.; Zastenker, G. N.; Šafránková, J.; Němeček, Z.; Přech, L.

    2016-07-01

    We present a comparison of spectral and statistical properties of ion flux fluctuations in the turbulent solar wind and in the flank Earth's magnetosheath. We use the data of the BMSW device operating in frame of the SPECTR-R mission with an extremely high-time resolution (up to ∼30 ms). Fourier spectra of ion flux fluctuations are systematically analyzed both in the solar wind and in the magnetosheath on the inertial scale and on a transition to the dissipation scale in the range of 0.01-10 Hz. We show that ion flux fluctuation spectra in the flank magnetosheath are similar to those observed in the solar wind and we demonstrate the presence of the break at frequencies of ∼1-2 Hz. Spectra are slightly steeper in the flank magnetosheath but the break frequency is near twice less in a comparison to the solar wind. The magnetosheath ion flux turbulent flow is intermittent as it was shown earlier for the solar wind. We discuss the level of intermittency of ion flux fluctuations in both regions and we determine the characteristics of structure functions. Finally, we demonstrate extended self-similarity in the magnetosheath.

  8. Flanking Residues Are Central to DO11.10 T Cell Hybridoma Stimulation by Ovalbumin 323–339

    PubMed Central

    Roy, Benjamin M.; Zhukov, Dmitriy V.; Maynard, Jennifer A.

    2012-01-01

    T cell activation requires formation of a tri-molecular interaction between a major histocompatibility complex (MHC), peptide, and T cell receptor. In a common model system, the ovalbumin epitope 323–339 binds the murine class II MHC, I-Ad, in at least three distinct registers. The DO11.10 T cell recognizes the least stable of these, as determined by peptide-MHC dissociation rates. Using exogenous peptides and peptide insertions into a carrier protein in combination with IL-2 secretion assays, we show that the alternate registers do not competitively inhibit display of the active register four. In contrast, this weakly binding register is stabilized by the presence of n-terminal flanking residues active in MHC binding. The DO11.10 hybridoma is sensitive to the presence of specific wild-type residues extending to at least the P-3 peptide position. Transfer of the P-4 to P-2 flanking residues to a hen egg lysozyme epitope also presented by I-Ad increases the activity of that epitope substantially. These results illustrate the inherent complexity in delineating the interaction of multiple registers based on traditional thermodynamic measurements and demonstrate the potential of flanking residue modification for increasing the activity of weakly bound epitopes. The latter technique represents an alternative to substitution of anchor residues within a weakly bound register, which we show can significantly decrease the activity of the epitope to a responding T cell. PMID:23110081

  9. Trawling-induced daily sediment resuspension in the flank of a Mediterranean submarine canyon

    NASA Astrophysics Data System (ADS)

    Martín, Jacobo; Puig, Pere; Palanques, Albert; Ribó, Marta

    2014-06-01

    Commercial bottom trawling is one of the anthropogenic activities causing the biggest impact on the seafloor due to its recurrence and global distribution. In particular, trawling has been proposed as a major driver of sediment dynamics at depths below the reach of storm waves, but the issue is at present poorly documented with direct observations. This paper analyses changes in water turbidity in a tributary valley of the La Fonera (=Palamós) submarine canyon, whose flanks are routinely exploited by a local trawling fleet down to depths of 800 m. A string of turbidimeters was deployed at 980 m water depth inside the tributary for two consecutive years, 2010-2011. The second year, an ADCP profiled the currents 80 m above the seafloor. The results illustrate that near-bottom water turbidity at the study site is heavily dominated, both in its magnitude and temporal patterns, by trawling-induced sediment resuspension at the fishing ground. Resuspended sediments are channelised along the tributary in the form of sediment gravity flows, being recorded only during working days and working hours of the trawling fleet. These sediment gravity flows generate turbid plumes that extend to at least 100 m above the bottom, reaching suspended sediment concentrations up to 236 mg l-1 close to the seafloor (5 m above bottom). A few hours after the end of daily trawling activities, water turbidity progressively decreases but resuspended particles remain in suspension for several hours, developing bottom and intermediate nepheloid layers that reach background levels ˜2 mg l-1 before trawling activities resume. The presence of these nepheloid layers was recorded in a CTD+turbidimeter transect conducted across the fishing ground a few hours after the end of a working day. These results highlight that deep bottom trawling can effectively replace natural processes as the main driving force of sediment resuspension on continental slope regions and generate increased near-bottom water

  10. A giant landslide on the north flank of Tenerife, Canary Islands

    NASA Astrophysics Data System (ADS)

    Watts, A. B.; Masson, D. G.

    1995-12-01

    The extent of mass wasting along the north flank of Tenerife has been mapped using swath bathymetry, GLORIA side-scan sonar, and 3.5-kHz echo sounder data. The marine surveys show that, north of Tenerife, a giant landslide is exposed over an area of 5500 km2 of the seafloor, more than twice the surface area of the island. The landslide truncates an older ridge and valley topography that is associated with the shield building basalts on Tenerife. We interpret the ridge and valley topography as the result of subaerial erosion. The landslide is estimated to have a length of 100 km, a width of up to 80 km, and a volume of about 1000 km3. It extends onshore into the Orotava and Icod valleys which have been interpreted as of landslide origin. K-Ar dating of basaltic flows in the steep headwall of Orotava suggests an age of formation for the valley is younger than 0.78 Ma and may even be younger than 0.27 Ma. The Icod valley is located immediately to the north of the most recent volcano on Tenerife, Las Cañadas, and has been associated with the collapse of its caldera, between 1.2 and 0.2 Ma. A young age for the landslide is supported by the 3.5-kHz echo sounder data which show that the landslide is draped by a thin (< 10 m) layer of younger sediment. The landslide did not form, however, during a single catastrophic event but represents the amalgamation of a number of separate landslides. The occurrence of the ridge and valley topography in water depths of up to 2.5 km suggests that the shield-building basalts have subsided by at least this amount since they formed, 3.3-8.0 Ma. We speculate that this subsidence is caused by some form of stress relaxation that occurs in the underlying lithosphere. The giant landslide imaged in our sonar data is associated with the late stages in the development of the most recent volcano on Tenerife, Las Canadas, which only began at about 1.8 Ma. Thus landsliding may be a particular feature of the time soon after emplacement when because

  11. Active faults on the eastern flank of Etna volcano (Italy) monitored through soil radon measurements

    NASA Astrophysics Data System (ADS)

    Neri, M.; Giammanco, S.; Ferrera, E.; Patanè, G.; Zanon, V.

    2012-04-01

    This study concerns measurements of radon and thoron emissions from soil carried out in 2004 on the unstable eastern flank of Mt. Etna, in a zone characterized by the presence of numerous seismogenic and aseismic faults. The statistical treatment of the geochemical data allowed recognizing anomaly thresholds for both parameters and producing distribution maps that highlighted a significant spatial correlation between soil gas anomalies and tectonic lineaments. In particular, the highest anomalies were found at the intersection between WNW-ESE and NW-SE -running faults. The seismic activity occurring in and around the study area during 2004 was analyzed, producing maps of hypocentral depth and released seismic energy. These maps revealed a progressive deepening of hypocenters from NW to SE, with the exception of a narrow zone in the central part of the area, with a roughly WNW-ESE direction. Also, the highest values of seismic energy were released during events in the southern and northwestern sectors of the area. Both radon and thoron anomalies were located in areas affected by relatively deep (5-10 km depth) seismic activity, while less evident correlation was found between soil gas anomalies and the released seismic energy. This study confirms that mapping the distribution of radon and thoron in soil gas can reveal hidden faults buried by recent soil cover or faults that are not clearly visible at the surface. The correlation between soil gas data and earthquake depth and intensity can give some hints on the source of gas and/or on fault dynamics. Lastly, an important spin-off of this study is the recognition of some areas where radon activity was so high (>50000 Bq/m3) that it may represent a potential hazard to the local population. In fact, radon is the leading cause of lung cancer after cigarette smoke for long exposures and, due to its molecular weight, it accumulates in underground rooms or in low ground, particularly where air circulation is low or absent

  12. Adhesive and Migratory Effects of Phosphophoryn Are Modulated by Flanking Peptides of the Integrin Binding Motif

    PubMed Central

    Suzuki, Shigeki; Kobuke, Seiji; Haruyama, Naoto; Hoshino, Hiroaki; Kulkarni, Ashok B.; Nishimura, Fusanori

    2014-01-01

    Phosphophoryn (PP) is generated from the proteolytic cleavage of dentin sialophosphoprotein (DSPP). Gene duplications in the ancestor dentin matrix protein-1 (DMP-1) genomic sequence created the DSPP gene in toothed animals. PP and DMP-1 are phosphorylated extracellular matrix proteins that belong to the family of small integrin-binding ligand N-linked glycoproteins (SIBLINGs). Many SIBLING members have been shown to evoke various cell responses through the integrin-binding Arg-Gly-Asp (RGD) domain; however, the RGD-dependent function of PP is not yet fully understood. We demonstrated that recombinant PP did not exhibit any obvious cell adhesion ability, whereas the simultaneously purified recombinant DMP-1 did. A cell adhesion inhibitory analysis was performed by pre-incubating human osteosarcoma MG63 cells with various PP peptides before seeding onto vitronectin. The results obtained revealed that the incorporation of more than one amino acid on both sides of the PP-RGD domain was unable to inhibit the adhesion of MG63 cells onto vitronectin. Furthermore, the inhibitory activity of a peptide containing the PP-RGD domain with an open carboxyl-terminal side (H-463SDESDTNSESANESGSRGDA482-OH) was more potent than that of a peptide containing the RGD domain with an open amino-terminal side (H-478SRGDASYTSDESSDDDNDSDSH499-OH). This phenomenon was supported by the potent cell adhesion and migration abilities of the recombinant truncated PP, which terminated with Ala482. Furthermore, various point mutations in Ala482 and/or Ser483 converted recombinant PP into cell-adhesive proteins. Therefore, we concluded that the Ala482-Ser483 flanking sequence, which was detected in primates and mice, was the key peptide bond that allowed the PP-RGD domain to be sequestered. The differential abilities of PP and DMP-1 to act on integrin imply that DSPP was duplicated from DMP-1 to serve as a crucial extracellular protein for tooth development rather than as an integrin

  13. Crustal structure along the west flank of the Cascades, western Washington

    NASA Astrophysics Data System (ADS)

    Miller, Kate C.; Keller, G. Randy; Gridley, James M.; Luetgert, James H.; Mooney, Walter D.; Thybo, Hans

    1997-08-01

    Knowledge of the crustal structure of the Washington Cascades and adjacent Puget Lowland is important to both earthquake hazards studies and geologic studies of the evolution of this tectonically active region. We present a model for crustal velocity structure derived from analysis of seismic refraction/wide-angle reflection data collected in 1991 in western Washington. The 280-km-long north-south transect skirts the west flank of the Cascades as it crosses three tectonic provinces including the Northwest Cascades Thrust System (NWCS), the Puget Lowland, and the volcanic arc of the southern Cascades. Within the NWCS, upper crustal velocities range from 4.2 to 5.7 km s-1 and are consistent with the presence of a diverse suite of Mesozoic and Paleozoic metasediments and metavolcanics. In the upper 2-3 km of the Puget Lowland velocities drop to 1.7-3.5 km s-1 and reflect the occurrence of Oligocene to recent sediments within the basin. In the southern Washington Cascades, upper crustal velocities range from 4.0 to 5.5 km s-1 and are consistent with a large volume of Tertiary sediments and volcanics. A sharp change in velocity gradient at 5-10 km marks the division between the upper and middle crust. From approximately 10 to 35 km depth the velocity field is characterized by a velocity increase from ˜6.0 to 7.2 km s-1. These high velocities do not support the presence of marine sedimentary rocks at depths of 10-20 km beneath the Cascades as previously proposed on the basis of magnetotelluric data. Crustal thickness ranges from 42 to 47 km along the profile. The lowermost crust consists of a 2 to 8-km-thick transitional layer with velocities of 7.3-7.4 km s-1. The upper mantle velocity appears to be an unusually low 7.6-7.8 km s-1. When compared to velocity models from other regions, this model most closely resembles those found in active continental arcs. Distinct seismicity patterns can be associated with individual tectonic provinces along the seismic transect. In

  14. Composition of pore and spring waters from Baby Bare: Global implications of geochemical fluxes from a ridge flank hydrothermal system

    SciTech Connect

    Wheat, C.G.; Mottl, M.J.

    2000-02-01

    Warm hydrothermal springs were discovered on Baby Bare, which is an isolated basement outcrop on 3.5 Ma-old crust on the eastern flank of the Juan de Fuca Ridge. The authors have sampled these spring waters from a manned submersible, along with associated sediment pore waters from 48 gravity and piston cores. Systematic variations in the chemical composition of these waters indicate that hydrothermal reactions in basement at moderate temperatures remove Na, K, Li, Rb, Mg, TCO{sub 2}, alkalinity, and phosphate from the circulating seawater and leach Ca, Sr, Si, B, and Mn from the oceanic crust; and that reactions with the turbidite sediment surrounding Baby Bare remove Na, Li, Mg, Ca, Sr, and sulfate from the pore water while producing ammonium and Si and both producing and consuming phosphate, nitrate, alkalinity, Mn, and Fe. K, Rb, and B are relatively unreactive in the sediment column. The composition of altered seawater in basement at Baby Bare is similar to the inferred composition of 58 C formation water from crust nearly twice as old (5.9 Ma) on the southern flank of the Costa Rica Rift. The Baby Bare fluids also exhibit the same directions of net elemental transfer between basalt and seawater as solutions produced in laboratory experiments at a similar temperature, and complement compositional changes form seawater observed in seafloor basalts altered at cool to moderate temperatures. The common parameter among the two ridge flanks and experiments is temperature, suggesting that the residence time of seawater in the two ridge-flank sites is sufficiently long for the solutions to equilibrate with altered basalt. The authors use the Baby Bare spring water to estimate upper limits on the global fluxes of 14 elements at warm ridge-flank sites such as Baby Bare. Maximum calculated fluxes of Mg, Ca, sulfate, B, and K may equal or exceed 25% of the riverine flux, and such sites may represent the missing, high K/Rb sink required for the K budget.

  15. Investigating the potential for volcano flank instability triggered by recent dike intrusions at Fogo volcano, Cape Verde

    NASA Astrophysics Data System (ADS)

    Bagnardi, Marco; González, Pablo; Hooper, Andrew; Wright, Tim

    2015-04-01

    Gravitational flank-collapses at volcanoes are rare but catastrophic events that have rarely been witnessed by humans (e.g., Mount St. Helens in 1980). It has been proposed that gravitationally unstable volcanic flanks can be classified in two different types based on the flanks slope: volcanoes characterized by gentle slopes (Hawaiian-like) and that have very dynamic flanks exhibiting high rates of deformation and, conversely, steep-sided volcanoes (Macaronesian-like) showing minimal ground deformation. The two types of volcanoes could therefore reach the stable-state through different mechanisms and experience different mass-wasting processes. Numerous giant debris-avalanche deposits have been identified offshore the volcanoes of the Canary Islands and Cape Verde. Given the steep slopes of these volcanoes, the mass-wasting events may have occurred suddenly and with minimal precursory signals. Several mechanisms have been proposed as potential triggers and among these the intrusion of shallow dikes feeding fissure eruptions is one of the best candidates. In this work, we investigate this hypothesis in the light of new and revised results derived from the analysis of geodetic observations at Fogo volcano (Cape Verde). Fogo has erupted twice in the last 20 years (1995 and 2014-2015) and in both occasions the volcano erupted along fissures that seem to be fed by dykes intruding the shallow crust and the volcanic edifice. We re-process radar data from the ERS satellite to obtain state-of-the-art deformation maps spanning the 1995 eruption and revisit previously proposed models of the magmatic system. Our results indicate that both eruptions were fed by sub-vertical dikes, steeply dipping to the SE, and radiating from the Pico do Fogo volcanic cone to the SW. We also study the effect of such magmatic intrusions in terms of the stress regime that they generate and analyze whether the 1995 and 2014 intrusions could potentially destabilize the structures along which a

  16. Crustal structure along the west flank of the Cascades, western Washington

    USGS Publications Warehouse

    Miller, K.C.; Keller, Gordon R.; Gridley, J.M.; Luetgert, J.H.; Mooney, W.D.; Thybo, H.

    1997-01-01

    Knowledge of the crustal structure of the Washington Cascades and adjacent Puget Lowland is important to both earthquake hazards studies and geologic studies of the evolution of this tectonically active region. We present a model for crustal velocity structure derived from analysis of seismic refraction/wide-angle reflection data collected in 1991 in western Washington. The 280-km-long north-south transect skirts the west flank of the Cascades as it crosses three tectonic provinces including the Northwest Cascades Thrust System (NWCS), the Puget Lowland, and the volcanic arc of the southern Cascades. Within the NWCS, upper crustal velocities range from 4.2 to 5.7 km s-1 and are consistent with the presence of a diverse suite of Mesozoic and Paleozoic metasediments and metavolcanics. In the upper 2-3 km of the Puget Lowland velocities drop to 1.7-3.5 km s-1 and reflect the occurrence of Oligocene to recent sediments within the basin. In the southern Washington Cascades, upper crustal velocities range from 4.0 to 5.5 km s-1 and are consistent with a large volume of Tertiary sediments and volcanics. A sharp change in velocity gradient at 5-10 km marks the division between the upper and middle crust. From approximately 10 to 35 km depth the velocity field is characterized by a velocity increase from ???6.0 to 7.2 km s-1. These high velocities do not support the presence of marine sedimentary rocks at depths of 10-20 km beneath the Cascades as previously proposed on the basis of magnetotelluric data. Crustal thickness ranges from 42 to 47 km along the profile. The lowermost crust consists of a 2 to 8-km-thick transitional layer with velocities of 7.3-7.4 km s-1. The upper mantle velocity appears to be an unusually low 7.6-7.8 km s-1. When compared to velocity models from other regions, this model most closely resembles those found in active continental arcs. Distinct seismicity patterns can be associated with individual tectonic provinces along the seismic transect. In

  17. A-T linker adapter polymerase chain reaction for determining flanking sequences by rescuing inverse PCR or thermal asymmetric interlaced PCR products.

    PubMed

    Trinh, Quoclinh; Zhu, Pengyu; Shi, Hui; Xu, Wentao; Hao, Junran; Luo, Yunbo; Huang, Kunlun

    2014-12-01

    The polymerase chain reaction (PCR)-based genome walking method has been extensively used to isolate unknown flanking sequences, whereas nonspecific products are always inevitable. To resolve these problems, we developed a new strategy to isolate the unknown flanking sequences by combining A-T linker adapter PCR with inverse PCR (I-PCR) or thermal asymmetric interlaced PCR (TAIL-PCR). The result showed that this method can be efficiently achieved with the flanking sequence from the Arabidopsis mutant and papain gene. Our study provides researchers with an additional method for determining genomic DNA flanking sequences to identify the target band from bulk of bands and to eliminate the cloning step for sequencing. PMID:25086366

  18. Sheared sheet intrusions as a mechanism for lateral flank displacement on basaltic volcanoes: Applications to Réunion Island volcanoes

    NASA Astrophysics Data System (ADS)

    Cayol, V.; Catry, T.; Michon, L.; Chaput, M.; Famin, V.; Bodart, O.; Froger, J. L.; Romagnoli, C.

    2014-12-01

    Field work carried out on the Piton des Neiges volcano (Réunion Island) suggests that the injection of magma along detachments could trigger flank failure by conjugate opening and shear displacement [Famin and Michon, 2010]. We use 3D numerical models to compare the ability of purely opened sheet intrusions, sheared sheet intrusions, and normal faults to induce flank displacement on basaltic volcanoes (Figure). We assume that shear stress change on fractures which are not normal to a principal stress results from stress anisotropy of the host rock under gravity. Exploring a large range of stress anisotropies, fracture dips, and fracture depth over length ratios, we determine that the amount of shear displacement is independent of the proximity to the ground surface. Sheared sheet intrusions are the most efficient slip medium on volcanoes. Using our model in a forward way, we provide shear and normal displacements for buried fractures. Applying the model to a pile of sills at the Piton des Neiges volcano, we determine that the mean shear displacement caused by each intrusion was 3.7 m, leading to a total of a 180-260 m of lateral displacement for the 50 m high pile of sills. Using our model in an inverse way, we formulate a decision tree to determine some fracture characteristics and the host rock stress anisotropy from ratios of maximum surface displacements. This procedure provides a priori models, thus limits to the parameter space which can be further explored through a formal inversion. Applying this procedure to the 1.4 m co-eruptive flank displacement recorded at Piton de la Fournaise in 2007, we find that it probably originated from a shallow eastward-dipping sub-horizontal normal fault.

  19. Abyssal Hill Segmentation: Quantitative analysis of the East Pacific Rise flanks 7°S-9°S

    NASA Astrophysics Data System (ADS)

    Goff, John A.; Malinverno, Alberto; Fornari, Daniel J.; Cochran, James R.

    1993-08-01

    The recent R/V Maurice Ewing EW9105 Hydrosweep survey of the East Pacific Rise (EPR) and adjacent flanks between 7°S and 9°S provides an excellent opportunity to explore the causal relationship between the ridge and the abyssal hills which form on its flanks. These data cover 100% of the flanking abyssal hills to 115 km on either side of the axis. We apply the methodology of Goff and Jordan (1988) for estimating statistical characteristics of abyssal hill morphology (rms height, characteristic lengths and widths, plan view aspect ratio, azimuthal orientation, and fractal dimension). Principal observations include the following: (1) the rms height of abyssal hill morphology is negatively correlated with the width of the 5- to 20-km-wide crestal high, consistent with the observations of Goff (1991) for northern EPR abyssal hill morphology; (2) the characteristic abyssal hill width displays no systematic variation with position relative to ridge segmentation within the EW9105 survey area, in contrast with observations of Goff (1991) for northern EPR abyssal hill morphology in which characteristic widths tend to be smallest at segment ends and largest toward the middle of segments; (3) abyssal hill rms heights and characteristic widths are very large just north of a counterclockwise rotating "nannoplate", suggesting that the overlap region is being pushed northward in response to microplate-style tectonics; and (4) within the 7°12'S-8°38'S segment, abyssal hill lineaments are generally parallel to the ridge axis, while south of this area, abyssal hill lineaments rotate with a larger "radius of curvature" than does the EPR axis approaching the EPR-Wilkes ridge-transform intersection.

  20. Self-potential Anomalies Around the Earthquake Swarm Area in the Southeastern Flank of Ontake Volcano, Central Japan

    NASA Astrophysics Data System (ADS)

    Yoshimura, R.; Yamazaki, K.; Okada, Y.; Oshiman, N.

    2006-12-01

    Ontake Volcano is located in the southern end of the Norikura Volcanic Chain, central Japan, close to the junction of the Izu Bonin and Mariana and Southwestern Japan volcanic arcs. It is almost conical and made of andesite. Earthquake swarm activity has been continuously observed around the southeastern flank of Mt. Ontake since 1976. A phreatic explosion occurred in 1979 at a fissure on the southwestern slope of the Kengamine, the main peak of Mt. Ontake. And a large earthquake with the depth about 2 km and a magnitude of 6.8 occurred in 1984 in the southeastern flank of the volcano. Recently, Kimata et al. (2004) revealed uplift ground deformation above the earthquake swarm area by using repeated leveling. Furthermore, Magnetotelluric soundings estimated a low resistivity region with the depth about 2km beneath the uplift area [Kasaya et al., 2002]. In order to investigate a relationship between tectonic movements and subsurface low resistivity zone, we carried out self-potential(SP) measurements from 2003 and 2006 around the focal region of the 1984 Earthquake and the summit area of Mt. Ontake. The equipment for measuring surface self-potentials consists of a pair of non-polarizing copper-copper sulfate/silver-silver chloride electrodes, an insulated connecting conductor cable, and a high input impedance digital multimeter. In this survey, profiles totaling to about 90km length (982 sites) were made, with an average measurement interval of 100m. Two distinctive SP features are found around the active earthquake cluster and inside of the aseismic area of southeastern flank of Mt. Ontake. In this presentation, we will report a detail of SP measurements and results.

  1. Molecular cloning, SNP detection and association analysis of 5' flanking region of the goat IGF1 gene with prolificacy.

    PubMed

    Thomas, Naicy; Venkatachalapathy, Thirupathy; Aravindakshan, Thazhathuveettil; Raghavan, K C

    2016-04-01

    The insulin-like growth factor 1 has an important role in reproduction, foetal development and growth. It regulates the secretion of gonadotrophin releasing hormone, stimulates ovarian function and steroidogenesis. The present study was conducted to characterise the 5' flanking region of goat IGF 1 gene, ascertain ovarian expression of the IGF1 gene, detect SNPs and assess the association with prolificacy in the two indigenous goat breeds of South India viz., low prolific Attappady Black and high prolific Malabari. The 5' flanking region of IGF1 gene was PCR amplified, cloned and sequenced from both breeds. Genotyping was performed in 277 goats from the two genetic groups using the PCR-Single Strand Conformational Polymorphism (SSCP) and the expression of the IGF1 gene in the ovary was analysed by quantitative real time PCR. The 5' flanking region of the IGF1 gene was 601 bp long and located at 450 bp upstream of the start codon. Sequence exhibited 97-99% similarity with that of the sheep, cattle and sika deer IGF1 genes. Three genotypes, PP, PQ and QR were observed at this locus with the frequency of 0.62, 0.30 and 0.08, respectively. Sequencing of the representative PCR products from each genotype revealed two SNPs, g.224A>G and g.227C>T. The population was found to be in Hardy-Weinberg disequilibrium at both loci. Statistical results indicated that these loci were associated with litter size (P ≤ 0.05). However, no significant difference was found in the expression of the IGF1 gene in the ovaries of the two goat breeds. These results suggest the significant influence of the IGF1 gene on prolificacy in goats and identified SNPs would benefit the selection of prolific animals in future breeding programs. PMID:26852275

  2. Microbial communities at the borehole observatory on the Costa Rica Rift flank (Ocean Drilling Program Hole 896A)

    PubMed Central

    Nigro, Lisa M.; Harris, Kate; Orcutt, Beth N.; Hyde, Andrew; Clayton-Luce, Samuel; Becker, Keir; Teske, Andreas

    2012-01-01

    The microbiology of subsurface, hydrothermally influenced basaltic crust flanking mid-ocean ridges has remained understudied, due to the difficulty in accessing the subsurface environment. The instrumented boreholes resulting from scientific ocean drilling offer access to samples of the formation fluids circulating through oceanic crust. We analyzed the phylogenetic diversity of bacterial communities of fluid and microbial mat samples collected in situ from the observatory at Ocean Drilling Program Hole 896A, drilled into ~6.5 million-year-old basaltic crust on the flank of the Costa Rica Rift in the equatorial Pacific Ocean. Bacterial 16S rRNA gene sequences recovered from borehole fluid and from a microbial mat coating the outer surface of the fluid port revealed both unique and shared phylotypes. The dominant bacterial clones from both samples were related to the autotrophic, sulfur-oxidizing genus Thiomicrospira. Both samples yielded diverse gamma- and alphaproteobacterial phylotypes, as well as members of the Bacteroidetes, Planctomycetes, and Verrucomicrobia. Analysis of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) genes (cbbL and cbbM) from the sampling port mat and from the borehole fluid demonstrated autotrophic carbon assimilation potential for in situ microbial communities; most cbbL genes were related to those of the sulfur-oxidizing genera Thioalkalivibrio and Thiomicrospira, and cbbM genes were affiliated with uncultured phylotypes from hydrothermal vent plumes and marine sediments. Several 16S rRNA gene phylotypes from the 896A observatory grouped with phylotypes recovered from seawater-exposed basalts and sulfide deposits at inactive hydrothermal vents, but there is little overlap with hydrothermally influenced basaltic boreholes 1026B and U1301A on the Juan de Fuca Ridge flank, suggesting that site-specific characteristics of Hole 896A (i.e., seawater mixing into borehole fluids) affect the microbial community composition. PMID

  3. Seismo-tectonic behavior of the Pernicana Fault System (Mt Etna): a gauge for volcano flank instability?

    NASA Astrophysics Data System (ADS)

    Ruch, J.; Pepe, S.; Casu, F.; Solaro, G.; Pepe, A.; Acocella, V.; Neri, M.; Sansosti, E.

    2013-12-01

    Flank instability at basaltic volcanoes is often related to repeated dike intrusions along rift zones and accompanied by surface fracturing and seismicity. These processes have been mostly studied during specific events, and the lack of longer-term observations hinders their better understanding. Here we analyze ~20 years of deformation of the Pernicana Fault System (PFS), the key structure controlling the instability of the eastern flank of Mt. Etna. We exploit East-West and vertical components of mean deformation velocity, as well as corresponding time series, computed from ERS/ENVISAT (1992-2010) and COSMO-SkyMed (2009-2011) satellite radar sensors via Synthetic Aperture Radar Interferometry (InSAR) techniques. We then integrate and compare this information with field, seismic and leveling data, collected between 1980 and 2012. We observe transient displacements accompanied by seismicity, overprinted on a long-term background eastward motion (˜2 cm/yr). In the last decades, these transient events were preceded by a constant amount of accumulated strain near the PFS. The time of strain accumulation varies between a few years and a few decades, also depending on magma emplacement within the nearby NE Rift, which may increase the strain along the PFS. These results suggest that the amount of deformation near the PFS may be used as a gauge to forecast the occurrence of instability transients on the eastern flank of Etna. In this context, the PFS may provide an ideal, small-scale structure to test the relations between strain accumulation, stress loading and seismic energy release.

  4. Shadow enhancers flanking the HoxB cluster direct dynamic Hox expression in early heart and endoderm development.

    PubMed

    Nolte, Christof; Jinks, Tim; Wang, Xinghao; Martinez Pastor, María Teresa; Krumlauf, Robb

    2013-11-01

    The products of Hox genes function in assigning positional identity along the anterior-posterior body axis during animal development. In mouse embryos, Hox genes located at the 3' end of HoxA and HoxB complexes are expressed in nested patterns in the progenitors of the secondary heart field during early cardiogenesis and the combined activities of both of these clusters are required for proper looping of the heart. Using Hox bacterial artificial chromosomes (BACs), transposon reporters, and transgenic analyses in mice, we present the identification of several novel enhancers flanking the HoxB complex which can work over a long range to mediate dynamic reporter expression in the endoderm and embryonic heart during development. These enhancers respond to exogenously added retinoic acid and we have identified two retinoic acid response elements (RAREs) within these control modules that play a role in potentiating their regulatory activity. Deletion analysis in HoxB BAC reporters reveals that these control modules, spread throughout the flanking intergenic region, have regulatory activities that overlap with other local enhancers. This suggests that they function as shadow enhancers to modulate the expression of genes from the HoxB complex during cardiac development. Regulatory analysis of the HoxA complex reveals that it also has enhancers in the 3' flanking region which contain RAREs and have the potential to modulate expression in endoderm and heart tissues. Together, the similarities in their location, enhancer output, and dependence on retinoid signaling suggest that a conserved cis-regulatory cassette located in the 3' proximal regions adjacent to the HoxA and HoxB complexes evolved to modulate Hox gene expression during mammalian cardiac and endoderm development. This suggests a common regulatory mechanism, whereby the conserved control modules act over a long range on multiple Hox genes to generate nested patterns of HoxA and HoxB expression during

  5. Synthesis, spectroscopic characterization, and x-ray structural determination of W(CO)/sub 4/(PR/sub 3/)CNC/sub 6/H/sub 4/(PR/sub 3/ (R = Ph, Et)

    SciTech Connect

    Rommel, J.S.; Weinrach, J.B.; Grubisha, D.S.; Bennett, D.W.

    1988-08-24

    Two bimetallic complexes containing 1,4-diisocyanobenzene as a bridging ligand have been prepared and examined by x-ray crystallography and /sup 13/C NMR, /sup 31/P NMR, and infrared spectroscopies. W(CO)/sub 4/(PEt/sub 3/)CNC/sub 6/H/sub 4/NCW(CO)/sub 4/(PEt/sub 3/) (1) and W(CO)/sub 4/(PPh/sub 3/)CNC/sub 6/H/sub 4/NCW(CO)/sub 4/(PPh/sub 3/) (2) both crystallized in the same space group in very similar packing environments. Crystal data: for 1, monoclinic space group P2/sub 1//n,a = 7.780 (2) /angstrom/, b = 15.930 (3) /angstrom/, c = 14.137 (6) /angstrom/, /beta/ = 99.56 (3)/degree/, Z = 2, R = 0.040; for 2, monoclinic space group P2/sub 1//n, a = 11.641 (2) /angstrom/, b = 16.970 (2) /angstrom/, c = 12.463 (2), /angstrom/, /beta/ = 101.24 (1)/degree/, Z = 2, R = 0.047; NMR chemical shifts and vibrational frequencies for CNC/sub 6/H/sub 4/NC experience significant changes upon coordination, and the presence of an organophosphine ligand in the metal coordination sphere causes the diisocyanide to experience in-plane bends of 10.8/degrees/ for 1 and 4.2/degree/ for 2. In spite of strong evidence for the M-CNR back-bonding, the C-N bond length varies only negligibly among 1, 2, and CNC/sub 6/H/sub 4/NC, the free ligand. 20 references, 2 figures, 8 tables.

  6. Flank eruptions of Mt Etna during the Greek-Roman and Early Medieval periods: New data from 226Ra-230Th dating and archaeomagnetism

    NASA Astrophysics Data System (ADS)

    Branca, Stefano; Condomines, Michel; Tanguy, Jean-Claude

    2015-10-01

    In this paper, we present new data from 226Ra-230Th dating and archaeomagnetism with the aim of improving the knowledge of the flank eruptions that occurred at Mt Etna during the Greek-Roman and Early Medieval periods, as defined in the new geological map of the volcano. The combination of the two dating techniques demonstrates that three major flank eruptions occurred on the lower north and west flanks during Greek-Roman epochs, producing large scoria cones and extensive lava flows. In particular, the Mt Ruvolo and Mt Minardo events highly impacted the territory of the west flank, notably by damming the Simeto River. The new data of the Millicucco and Due Monti lava flows, on the lower north-east flank, indicate a younger age than their stratigraphic ages quoted in the 2011 geological map, since they occurred around 700 and 500 AD, respectively. None of the large flank eruptions occurring on the lower slopes of Etna during the Early Medieval age are reported in the historical sources. Overall, our paper shows that a comprehensive assessment of eruptions at Mount Etna in the last three millennia can only be achieved through a multidisciplinary approach.

  7. Experimental Evaluation and Optimization of Flank Wear During Turning of AISI 4340 Steel with Coated Carbide Inserts Using Different Cutting Fluids

    NASA Astrophysics Data System (ADS)

    Lawal, S. A.; Choudhury, I. A.; Nukman, Y.

    2015-01-01

    The understanding of cutting fluids performance in turning process is very important in order to improve the efficiency of the process. This efficiency can be determined based on certain process parameters such as flank wear, cutting forces developed, temperature developed at the tool chip interface, surface roughness on the work piece, etc. In this study, the objective is to determine the influence of cutting fluids on flank wear during turning of AISI 4340 with coated carbide inserts. The performances of three types of cutting fluids were compared using Taguchi experimental method. The results show that palm kernel oil based cutting fluids performed better than the other two cutting fluids in reducing flank wear. Mathematical models for cutting parameters such as cutting speed, feed rate, depth of cut and cutting fluids were obtained from regression analysis using MINITAB 14 software to predict flank wear. Experiments were conducted based on the optimized values to validate the regression equations for flank wear and 5.82 % error was obtained. The optimal cutting parameters for the flank wear using S/N ratio were 160 m/min of cutting speed (level 1), 0.18 mm/rev of feed (level 1), 1.75 mm of depth of cut (level 2) and 2.97 mm2/s palm kernel oil based cutting fluid (level 3). ANOVA shows cutting speed of 85.36 %; and feed rate 4.81 %) as significant factors.

  8. Amino acids flanking the central core of Cu,Zn superoxide dismutase are important in retaining enzyme activity after autoclaving.

    PubMed

    Kumar, Arun; Randhawa, Vinay; Acharya, Vishal; Singh, Kashmir; Kumar, Sanjay

    2016-01-01

    Enzymes are known to be denatured upon boiling, although Cu,Zn superoxide dismutase of Potentilla atrosanguinea (Pot-SOD) retains significant catalytic activity even after autoclaving (heating at 121 °C at a pressure of 1.1 kg per square cm for 20 min). The polypeptide backbone of Pot-SOD consists of 152 amino acids with a central core spanning His45 to Cys145 that is involved in coordination of Cu(2+) and Zn(2+) ions. While the central core is essential for imparting catalytic activity and structural stability to the enzyme, the role of sequences flanking the central core was not understood. Experiments with deletion mutants showed that the amino acid sequences flanking the central core were important in retaining activity of Pot-SOD after autoclaving. Molecular dynamics simulations demonstrated the unfavorable structure of mutants due to increased size of binding pocket and enhanced negative charge on the electrostatic surface, resulting in unavailability of the substrate superoxide radical ([Formula: see text]) to the catalytic pocket. Deletion caused destabilization of structural elements and reduced solvent accessibility that further produced unfavorable structural geometry of the protein. PMID:25990646

  9. Genomic footprinting of a yeast tRNA gene reveals stable complexes over the 5'-flanking region.

    PubMed Central

    Huibregtse, J M; Engelke, D R

    1989-01-01

    We have shown by genomic footprinting that the 5'-flanking region of the Saccharomyces cerevisiae tRNASUP53 gene is protected from DNase I digestion. The protected region has a 5' boundary at -40 (relative to the transcription initiation site) and extends into the coding region of the gene, with a 3' boundary at approximately +15. Although the DNase I protection over this region was much greater than at the A- and B-box internal promoters, point mutations within the A or B box that reduced transcription in vitro eliminated the upstream DNase I protection. This implies that formation of a stable complex over the 5'-flanking region is dependent on interaction of the gene with transcription factor IIIC but that stability of the complex may not require continued interaction with this factor. The DNase I protection under varied growth conditions further suggested that the upstream complex is composed of two or more components. The region over the transcription initiation site (approximately +15 to -10) was less protected in stationary-phase cultures, whereas the more upstream region (approximately -10 to -40) was protected in both exponential- and stationary-phase cultures. Images PMID:2677668

  10. Nitrogen Stimulates the Growth of Subsurface Basalt-associated Microorganisms at the Western Flank of the Mid-Atlantic Ridge

    PubMed Central

    Zhang, Xinxu; Fang, Jing; Bach, Wolfgang; Edwards, Katrina J.; Orcutt, Beth N.; Wang, Fengping

    2016-01-01

    Oceanic crust constitutes the largest aquifer system on Earth, and microbial activity in this environment has been inferred from various geochemical analyses. However, empirical documentation of microbial activity from subsurface basalts is still lacking, particularly in the cool (<25°C) regions of the crust, where are assumed to harbor active iron-oxidizing microbial communities. To test this hypothesis, we report the enrichment and isolation of crust-associated microorganisms from North Pond, a site of relatively young and cold basaltic basement on the western flank of the Mid-Atlantic Ridge that was sampled during Expedition 336 of the Integrated Ocean Drilling Program. Enrichment experiments with different carbon (bicarbonate, acetate, methane) and nitrogen (nitrate and ammonium) sources revealed significant cell growth (one magnitude higher cell abundance), higher intracellular DNA content, and increased Fe3+/ΣFe ratios only when nitrogen substrates were added. Furthermore, a Marinobacter strain with neutrophilic iron-oxidizing capabilities was isolated from the basalt. This work reveals that basalt-associated microorganisms at North Pond had the potential for activity and that microbial growth could be stimulated by in vitro nitrogen addition. Furthermore, iron oxidation is supported as an important process for microbial communities in subsurface basalts from young and cool ridge flank basement. PMID:27199959

  11. Organization and Functional Analysis of the 5′ Flanking Regions of Myostatin-1 and 2 Genes from Larimichthys crocea

    PubMed Central

    Dong, Xiaojing; Zhang, Xiaoju; Diallo, Amadou

    2012-01-01

    Myostatin (MSTN) is a negative regulator of skeletal muscle growth and development. There are two types of MSTNs in fish, but little is known about their gene regulation. Here, the 5′ flanking fragments of 1029 bp from MSTN-1 and 643 bp from MSTN-2 were cloned, sequenced, and analyzed in Larimichthys crocea. Both fragments contained CAAT box and several putative cis-regulatory elements. However, putative TATA box, MyoD, MEF3, SP1, USF, and GH-CSE sites were identified only in the L. crocea MSTN-1 (lcMSTN-1) promoter. Transcriptional activities of four fragments (1013, 841, 514, and 261 bp) truncated from lcMSTN-1 upstream region and two fragments (643 and 296 bp) from lcMSTN-2 upstream region were examined in vitro, using transient transfection in CIK and L6 cells. In CIK cells, the promoter activity correlated positively with the length of truncated fragments in both MSTN-1 and 2. The lcMSTN-2 promoter showed a higher activity than lcMSTN-1 in the corresponding region, which was consistent with MSTN gene expression in vivo. In L6 cells, lcMSTN-2 upstream showed an extremely high luciferase activity. These data indicated that both cloned 5′ flanking sequences contained functional promoters, and that transcription regulation of lcMSTN-1 and 2 promoters was significantly different between mammalian and fish cells. PMID:22149889

  12. Analysis of Pseudomonas putida alkane-degradation gene clusters and flanking insertion sequences: evolution and regulation of the alk genes.

    PubMed

    van Beilen, J B; Panke, S; Lucchini, S; Franchini, A G; Röthlisberger, M; Witholt, B

    2001-06-01

    The Pseudomonas putida GPo1 (commonly known as Pseudomonas oleovorans GPo1) alkBFGHJKL and alkST gene clusters, which encode proteins involved in the conversion of n-alkanes to fatty acids, are located end to end on the OCT plasmid, separated by 9.7 kb of DNA. This DNA segment encodes, amongst others, a methyl-accepting transducer protein (AlkN) that may be involved in chemotaxis to alkanes. In P. putida P1, the alkBFGHJKL and alkST gene clusters are flanked by almost identical copies of the insertion sequence ISPpu4, constituting a class 1 transposon. Other insertion sequences flank and interrupt the alk genes in both strains. Apart from the coding regions of the GPo1 and P1 alk genes (80-92% sequence identity), only the alkB and alkS promoter regions are conserved. Competition experiments suggest that highly conserved inverted repeats in the alkB and alkS promoter regions bind ALKS: PMID:11390693

  13. Active evaporite tectonics and collapse in the Eagle River valley and the southwestern flank of the White River uplift, Colorado

    USGS Publications Warehouse

    Scott, R.B.; Lidke, D.J.; Hudson, M.R.; Perry, W.J., Jr.; Bryant, Bruce; Kunk, M.J.; Budahn, J.R.; Byers, F.M., Jr.

    1999-01-01

    This field trip presents field evidence for Neogene evaporite tectonism, dissolution of evaporates, and related collapse in Eagle River valley and along the southwestern flank of the White River uplift. In the Eagle collapse center, Pennsylvanian evaporite flowed to form anticlinal diapirs, dissolved, and disrupted a lower Miocene basaltic plateau originally at elevations as high as 3.35 km by tilting, faulting, and sagging to elevations as low as about 2.1 km. Also in the Eagle collapse center, the 30 x 10-km, homoclinal Hardscrabble Mountain sank into evaporite during Triassic and Permian collapse followed by Neogene(?) tilting and collapse, based on seismic reflection data. Along the southwestern flank of the White River uplift in the northwestern part of the Carbondale collapse center, parts of the Grand Hogback monocline have collapsed northeastward toward a series of strike-elongate extrusive diapirs. The volume of evaporite removed from the Eagle and Carbondale collapse centers during the Neogene (about 2,250 km3 from an area of roughly 4,500 km2) was calculated by measuring the departure of collapsed basalts from an assumed original basalt plateau. Regional Neogene uplift and incision of the Rocky Mountains, which locally began about 8-10 Ma, probably triggered dissolution and collapse. Presently the Colorado River removes a dissolved-solids load of about 1.4 x 109 kg per year from the two collapse centers.

  14. The phylogeny of the social wasp subfamily Polistinae: evidence from microsatellite flanking sequences, mitochondrial COI sequence, and morphological characters

    PubMed Central

    Arévalo, Elisabeth; Zhu, Yong; Carpenter, James M; Strassmann, Joan E

    2004-01-01

    Background Social wasps in the subfamily Polistinae (Hymenoptera: Vespidae) have been important in studies of the evolution of sociality, kin selection, and within colony conflicts of interest. These studies have generally been conducted within species, because a resolved phylogeny among species is lacking. We used nuclear DNA microsatellite flanking sequences, mitochondrial COI sequence, and morphological characters to generate a phylogeny for the Polistinae (Hymenoptera) using 69 species. Results Our phylogeny is largely concordant with previous phylogenies at higher levels, and is more resolved at the species level. Our results support the monophyly of the New World subgenera of Polistini, while the Old World subgenera are a paraphyletic group. All genera for which we had more than one exemplar were supported as monophyletic except Polybia which is not resolved, and may be paraphyletic. Conclusion The combination of DNA sequences from flanks of microsatellite repeats with mtCOI sequences and morphological characters proved to be useful characters establishing relationships among the different subgenera and species of the Polistini. This is the first detailed hypothesis for the species of this important group. PMID:15070433

  15. Antigen Specificity of γδ T Cells Depends Primarily on the Flanking Sequences of CDR3δ*

    PubMed Central

    Xi, Xueyan; Guo, Yang; Chen, Hui; Xu, Chunping; Zhang, Huiyuan; Hu, Hongbo; Cui, Lianxian; Ba, Denian; He, Wei

    2009-01-01

    The structural basis that determines the specificity of γδ T cell receptor (TCR) recognition remains undefined. Our previous data show that the complementary determining region of human TCRδ (CDR3δ) is critical to ligand binding. Here we used linear and configurational approaches to examine the roles of V, N-D-N, or J regions in CDR3δ-mediated antigen recognition. Surprisingly, we found that the binding activities of CDR3δ from different γδ TCRs to their target tissues and ligands depend on the conserved flanking sequences (V and J) but not as much on the D region of CDR3δ fragment. We further defined the key residues in the V and J regions of CDR3δ fragments, including the cysteine residue in the V fragment and the leucine residue in the J fragment that determine their ligand binding specificity. Our results demonstrate that TCRδ primarily uses conserved flanking regions to bind ligands. This finding may provide an explanation for the limited number of γδ TCR ligands that have as yet been identified. PMID:19666468

  16. TM6, a Novel Nuclear Matrix Attachment Region, Enhances Its Flanking Gene Expression through Influencing Their Chromatin Structure

    PubMed Central

    Ji, Lusha; Xu, Rui; Lu, Longtao; Zhang, Jiedao; Yang, Guodong; Huang, Jinguang; Wu, Changai; Zheng, Chengchao

    2013-01-01

    Nuclear matrix attachment regions (MARs) regulate the higher-order organization of chromatin and affect the expression of their flanking genes. In this study, a tobacco MAR, TM6, was isolated and demonstrated to remarkably increase the expression of four different promoters that drive gusA gene and adjacent nptII gene. In turn, this expression enhanced the transformation frequency of transgenic tobacco. Deletion analysis of topoisomerase II-binding site, AT-rich element, and MAR recognition signature (MRS) showed that MRS has the highest contribution (61.7%) to the TM6 sequence-mediated transcription activation. Micrococcal nuclease (MNase) accessibility assay showed that 35S and NOS promoter regions with TM6 are more sensitive than those without TM6. The analysis also revealed that TM6 reduces promoter DNA methylation which can affect the gusA expression. In addition, two tobacco chromatin-associated proteins, NtMBP1 and NtHMGB, isolated using a yeast one-hybrid system, specifically bound to the TM6II-1 region (761 bp to 870 bp) and to the MRS element in the TM6II-2 (934 bp to 1,021 bp) region, respectively. We thus suggested that TM6 mediated its chromatin opening and chromatin accessibility of its flanking promoters with consequent enhancement of transcription. PMID:23852133

  17. Cluster observations of the dusk flank magnetopause near the sash: Ion dynamics and flow-through reconnection

    NASA Astrophysics Data System (ADS)

    Maynard, Nelson C.; Farrugia, Charles J.; Burke, William J.; Ober, Daniel M.; Mozer, Forrest S.; Rème, Henri; Dunlop, Malcolm; Siebert, Keith D.

    2012-10-01

    Compared to the dayside, dynamics on the flanks of the magnetopause are poorly understood. To help bridge this knowledge gap we analyzed Cluster plasma and field measurements acquired during a 90-min period on 20 November 2003 when Cluster crossed the magnetopause four times in the vicinity of the sash. MHD simulations provide a context for Cluster observations. Crossings were between the magnetosheath and an S-shaped plasma sheet, rather than to the open-field lobes of the magnetotail. Cluster encountered two regions of MHD-breaking differences between perpendicular ion velocities and E × B convection. Ion adiabatic expansion parameter (δi) calculations show that ion gyrotropy was not broken during an episode of strong Alfvén wave activity in the magnetosheath. However, gyrotropy was broken (δi > 1) during the fourth magnetopause crossing. In the magnetosheath, ion guiding-center motion was maintained but inertial effects associated with temporally varying electric fields are probable sources of velocity differences. Regarding the magnetopause crossing, the generalized Ohm's law limits possible sources for breaking ion gyrotropy to inertial forces and/or electron pressure gradients associated with a nearby reconnection event. We suggest that Cluster witnessed effects of a temporally varying and spatially limited, flow-through reconnection event between open mantle field lines from the two polar caps adding new closed flux to the LLBL at the sash. Future modeling of flank dynamics must consider inertial forces as significant drivers at the magnetopause and in the adjacent magnetosheath.

  18. Nitrogen Stimulates the Growth of Subsurface Basalt-associated Microorganisms at the Western Flank of the Mid-Atlantic Ridge.

    PubMed

    Zhang, Xinxu; Fang, Jing; Bach, Wolfgang; Edwards, Katrina J; Orcutt, Beth N; Wang, Fengping

    2016-01-01

    Oceanic crust constitutes the largest aquifer system on Earth, and microbial activity in this environment has been inferred from various geochemical analyses. However, empirical documentation of microbial activity from subsurface basalts is still lacking, particularly in the cool (<25°C) regions of the crust, where are assumed to harbor active iron-oxidizing microbial communities. To test this hypothesis, we report the enrichment and isolation of crust-associated microorganisms from North Pond, a site of relatively young and cold basaltic basement on the western flank of the Mid-Atlantic Ridge that was sampled during Expedition 336 of the Integrated Ocean Drilling Program. Enrichment experiments with different carbon (bicarbonate, acetate, methane) and nitrogen (nitrate and ammonium) sources revealed significant cell growth (one magnitude higher cell abundance), higher intracellular DNA content, and increased Fe(3+)/ΣFe ratios only when nitrogen substrates were added. Furthermore, a Marinobacter strain with neutrophilic iron-oxidizing capabilities was isolated from the basalt. This work reveals that basalt-associated microorganisms at North Pond had the potential for activity and that microbial growth could be stimulated by in vitro nitrogen addition. Furthermore, iron oxidation is supported as an important process for microbial communities in subsurface basalts from young and cool ridge flank basement. PMID:27199959

  19. Reconstruction of the Flanks of the Mid-Atlantic Ridge, 28° to 29° N: Implications for Evolution of Young Oceanic Lithosphere at Slow-Spreading Centers

    NASA Astrophysics Data System (ADS)

    Sloan, H.; Patriat, P.

    2004-12-01

    We reconstruct the flanks of the Mid-Atlantic Ridge between 28° and 29° N from 1 to 10 Ma at intervals of 1 Myr for the purpose of investigating evolution of young oceanic lithosphere morphology and its variation through time using an innovative method that combines seafloor subsidence correction with interpolated isochrons and rotation poles. Reconstruction results are consistent with formation of abyssal hills every 1 to 2 Myr in 2-3 Myr old lithosphere at the outer edge of the ridge mountains as a result of transition from dynamic regime near the axis to isostatic regime of the flanks. The oblique passage of structures formed at the axial valley walls through this transition zone may play a role in the development of inside corner high bathymetry. Asymmetric juxtaposition of abyssal hill morphology in reconstruction is indicative of independent formation and evolution of the morphotectonic fabric on opposing flanks. The two major factors affecting asymmetric ridge flank morphology are found to be sense of axial offset and fluctuation of magmatic activity at the segment scale. Sense of axial offset determines the relative distribution of inside and outside corner bathymetry on the flanks. Enhanced magma supply and associated segment propagation may contribute to half-spreading rate asymmetry, accretion of thicker crust, and formation of larger abyssal hills on the faster-spreading flank. Consistent alignment in reconstruction of the base of the steep walls bounding inside corner bathymetry confirms that they mark the boundaries between segments on the flanks and that the deep sediment filled basins, typically identified as discordant zones, are attributable to outside corner bathymetry.

  20. Preparation of Fe(3)O(4)@C@CNC multifunctional magnetic core/shell nanoparticles and their application in a signal-type flow-injection photoluminescence immunosensor.

    PubMed

    Chu, Chengchao; Li, Meng; Li, Long; Ge, Shenguang; Ge, Lei; Yu, Jinghua; Yan, Mei; Song, Xianrang

    2013-11-01

    We describe here the preparation of carbon-coated Fe3O4 magnetic nanoparticles that were further fabricated into multifunctional core/shell nanoparticles (Fe3O4@C@CNCs) through a layer-by-layer self-assembly process of carbon nanocrystals (CNCs). The nanoparticles were applied in a photoluminescence (PL) immunosensor to detect the carcinoembryonic antigen (CEA), and CEA primary antibody was immobilized onto the surface of the nanoparticles. In addition, CEA secondary antibody and glucose oxidase were covalently bonded to silica nanoparticles. After stepwise immunoreactions, the immunoreagent was injected into the PL cell using a flow-injection PL system. When glucose was injected, hydrogen peroxide was obtained because of glucose oxidase catalysis and quenched the PL of the Fe3O4@C@CNC nanoparticles. The here proposed PL immunosensor allowed us to determine CEA concentrations in the 0.005–50 ng·mL-1 concentration range, with a detection limit of 1.8 pg·mL-1. PMID:24121430

  1. Geology of the western, eastern and northern flanks of the Olympus Mons volcano as seen in HRSC and MOC images

    NASA Astrophysics Data System (ADS)

    Basilevsky, A. T.; Werner, S. C.; van Gasselt, S.; Neukum, G.; Dumke, A.; Ivanov, B. A.; Gwinner, K.

    This study is based on the analysis of images taken by MEX High Resolution Stereo Camera and in combination with MGS MOC images. 3-D imagery in the form of HRSC-based anaglyphs and DTMs were very helpful for the study. Our observation and analysis confirm the well-known interpretation of Olympus Mons as a giant shield volcano, but also show that this construct locally has probably partly been made of airborne dust (and/or ash) and ice layered deposits (Neukum et al, 2004; Basilevsky et al., 2005; this study). The deposits form mesas locally standing above the lava fields in the volcano western and eastern flanks as well as ridges locally observed at the top parts of the scarps rimming the Olympus construct on its western and northern flanks. The ridge tops stand a few hundred meters above the adjacent lava flows coming from the volcano top. Ice presence in these deposits was inferred from the presence of "collapse" features locally extending downslope as channel-like forms. The neutron-spectrometry measurements (Feldman et al., 2004) show a noticeable decrease in the neutron flux suggesting presence of up to 15-18 vol. % of equivalent water (ice) in the upper 1 m surface layer in the western part of the construct. The ice-rich deposits could have been emplaced during the epochs of high orbital inclination of Mars (Mishna et al., 2004) and could be partly preserved in the modern epoch due to protecting dust covers (Skorov et al., 2001). At the foot of the western slope of the volcano are seen flow-like features interpreted as remnants of rock glaciers (Lucchitta, 1981; Milkovich and Head, 2006). The dating by crater statistics shows that different areas of the Olympus Mons construct and lava fields at its foot have a spread of ages from >3.5 b.y. to 2 m.y. and glacier-like flows show a 0.5 b.y. to 4 m.y. age range. The eastern flank of the volcano shows a complex of morphologies caused by fluvial (channels), tectonic (wrinkle ridges) and volcanic (lava flows and

  2. Flank Collapse Assessment At Kick-'em-Jenny Submarine Volcano (Lesser Antilles): A Combined Approach Using Modelling and Experiments

    NASA Astrophysics Data System (ADS)

    Dondin, Frédéric; Heap, Michael; Robert, Richard E. A.; Dorville, Jean-Francois M.; Carey, Steven

    2016-04-01

    Volcanic landslides - the result of volcanic flank failure - are highly hazardous mass movements due to their high mobility, the wide area they can impact, and their potential to generate tsunamis. In the Lesser Antilles at least 53 episodes of flank collapse have been identified, with many of them associated with voluminous (Vdeposit exceeding 1 km3) submarine volcanic landslide deposits. The existence of such voluminous deposits highlights the hazard of potentially devastating tsunami waves to the populated islands of the Lesser Antilles. To help understand and mitigate such hazards, we applied a relative stability assessment method to the only active submarine volcano of the Lesser Antilles island arc: Kick-'em-Jenny (KeJ). KeJ - located 8 km north of the island of Grenada - is the southernmost edifice in the arc with recognized associated volcanic landslide deposits. From the three identified landslide prehistoric episodes, one is associated with a collapse volume of about 4.4 km3. Numerical simulations considering a single pulse collapse revealed that this episode would have produced a regional tsunami. A volume estimate of the present day edifice is about 1.5 km3. We aim to quantify potential initial volumes of collapsed material using relative instability analysis (RIA). The RIA evaluates the critical potential failure surface associated with factor of safety (Fs) inferior to 1 and compares them to areas of deficit/surplus of mass/volume obtained from the comparison of an high resolution digital elevation model of the edifice with an ideal 3D surface named Volcanoid. To do so we use freeware programs VolcanoFit 2.0 and SSAP 4.5. We report, for the first time, results of a Limit Equilibrium Method (Janbu's rigorous method) as a slope stability computation analysis performed using geomechanical parameters retrieved from rock mechanics tests performed on two rock basaltic-andesite rock samples collected from within the crater of the volcano during the 1

  3. Two encounters with the flank low-latitude boundary layer - Further evidence for closed field topology and investigation of the internal structure

    NASA Technical Reports Server (NTRS)

    Traver, D. P.; Mitchell, D. G.; Williams, D. J.; Frank, L. A.; Huang, C. Y.

    1991-01-01

    The structure of the flank low-latitude boundary layer (LLBL) is examined through differential energy spectra and particle angular anisotropies for traversals of the dawn flank (December 19, 1977) and dusk flank (July 7, 1978) during periods of predominantly northward magnetosheath field orientation. Spectra are presented that were obtained from combined ISEE 1 low-energy-proton and electron-differential-energy-analyzer and medium-energy-particle-instrument data extending over the 200-eV/q to 2-MeV energy range for the plasma sheet, stagnation region, outer LLBL, and magnetosheath regions. The stagnation region and the outer LLBL are each a mixture of plasma-sheet and magnetosheath populations, but the stagnation region contains a relatively higher fraction of plasma sheet particles, consistent with its placement earthward of the outer LLBL. Evidence for energization of thermal electrons appears during the dusk flank crossing. Bidirectional field-aligned ion distributions are observed with typically 5-to-1 enhancement of the flux along the magnetic field during certain portions of the dusk flank crossing.

  4. Identification of Genomic Insertion and Flanking Sequence of G2-EPSPS and GAT Transgenes in Soybean Using Whole Genome Sequencing Method

    PubMed Central

    Guo, Bingfu; Guo, Yong; Hong, Huilong; Qiu, Li-Juan

    2016-01-01

    Molecular characterization of sequence flanking exogenous fragment insertion is essential for safety assessment and labeling of genetically modified organism (GMO). In this study, the T-DNA insertion sites and flanking sequences were identified in two newly developed transgenic glyphosate-tolerant soybeans GE-J16 and ZH10-6 based on whole genome sequencing (WGS) method. More than 22.4 Gb sequence data (∼21 × coverage) for each line was generated on Illumina HiSeq 2500 platform. The junction reads mapped to boundaries of T-DNA and flanking sequences in these two events were identified by comparing all sequencing reads with soybean reference genome and sequence of transgenic vector. The putative insertion loci and flanking sequences were further confirmed by PCR amplification, Sanger sequencing, and co-segregation analysis. All these analyses supported that exogenous T-DNA fragments were integrated in positions of Chr19: 50543767–50543792 and Chr17: 7980527–7980541 in these two transgenic lines. Identification of genomic insertion sites of G2-EPSPS and GAT transgenes will facilitate the utilization of their glyphosate-tolerant traits in soybean breeding program. These results also demonstrated that WGS was a cost-effective and rapid method for identifying sites of T-DNA insertions and flanking sequences in soybean. PMID:27462336

  5. Identification of Genomic Insertion and Flanking Sequence of G2-EPSPS and GAT Transgenes in Soybean Using Whole Genome Sequencing Method.

    PubMed

    Guo, Bingfu; Guo, Yong; Hong, Huilong; Qiu, Li-Juan

    2016-01-01

    Molecular characterization of sequence flanking exogenous fragment insertion is essential for safety assessment and labeling of genetically modified organism (GMO). In this study, the T-DNA insertion sites and flanking sequences were identified in two newly developed transgenic glyphosate-tolerant soybeans GE-J16 and ZH10-6 based on whole genome sequencing (WGS) method. More than 22.4 Gb sequence data (∼21 × coverage) for each line was generated on Illumina HiSeq 2500 platform. The junction reads mapped to boundaries of T-DNA and flanking sequences in these two events were identified by comparing all sequencing reads with soybean reference genome and sequence of transgenic vector. The putative insertion loci and flanking sequences were further confirmed by PCR amplification, Sanger sequencing, and co-segregation analysis. All these analyses supported that exogenous T-DNA fragments were integrated in positions of Chr19: 50543767-50543792 and Chr17: 7980527-7980541 in these two transgenic lines. Identification of genomic insertion sites of G2-EPSPS and GAT transgenes will facilitate the utilization of their glyphosate-tolerant traits in soybean breeding program. These results also demonstrated that WGS was a cost-effective and rapid method for identifying sites of T-DNA insertions and flanking sequences in soybean. PMID:27462336

  6. The Kelvin-Helmholtz instability under Parker-Spiral Interplanetary Magnetic Field conditions at the magnetospheric flanks

    NASA Astrophysics Data System (ADS)

    Adamson, E.; Nykyri, K.; Otto, A.

    2016-07-01

    We have generated fully three-dimensional, high-resolution magnetohydrodynamic (MHD) simulations of the Kelvin-Helmholtz (KH) Instability during Parker-Spiral Interplanetary Magnetic Field (IMF) conditions at the dawnside magnetospheric flank magnetopause. Results of these simulations show that, although the draping of a strong tangential magnetic field component around the magnetopause, tailward of the terminator (due to the Parker-Spiral orientation), tends to stabilize the growth of such instabilities within the shear-flow plane, Kelvin-Helmholtz waves with a k -vector tilted out of this plane may, nonetheless, develop into the nonlinear phase. This result suggests that obliquely propagating KH waves may contribute to the dawn-dusk asymmetries observed in plasma sheet parameters.

  7. Microearthquake streaks and seismicity triggered by slow earthquakes on the mobile south flank of Kilauea Volcano, Hawai'i

    USGS Publications Warehouse

    Wolfe, C.J.; Brooks, B.A.; Foster, J.H.; Okubo, P.G.

    2007-01-01

    We perform waveform cross correlation and high precision relocation of both background seismicity and seismicity triggered by periodic slow earthquakes at Kilauea Volcano's mobile south flank. We demonstrate that the triggered seismicity dominantly occurs on several preexisting fault zones at the Hilina region. Regardless of the velocity model employed, the relocated earthquake epicenters and triggered seismicity localize onto distinct fault zones that form streaks aligned with the slow earthquake surface displacements determined from GPS. Due to the unknown effects of velocity heterogeneity and nonideal station coverage, our relocation analyses cannot distinguish whether some of these fault zones occur within the volcanic crust at shallow depths or whether all occur on the decollement between the volcano and preexisting oceanic crust at depths of ???8 km. Nonetheless, these Hilina fault zones consistently respond to stress perturbations from nearby slow earthquakes. Copyright 2007 by the American Geophysical Union.

  8. Revealing the hidden faults in the SE flank of Mt. Etna using radon in-soil gas measurement.

    PubMed

    Johnová, K; Thinová, L; Giammanco, S

    2014-07-01

    Although there are many methods for investigating tectonic structures, many faults remain hidden, and they can endanger the life and property of people living along them. The slopes of volcanoes are covered with such hidden faults, near which strong earthquakes and gas releases can appear. Revealing hidden faults can therefore contribute significantly to the protection of people living in volcanic areas. In the study, seven different techniques were used for making measurements of in-soil radon concentrations in order to search for hidden faults on the SE flank of the Mt. Etna volcano. These reported methods had previously been proved to be useful tools for investigating fault structures. The main aim of the experiment presented here was to evaluate the usability of these methods in the geological conditions of the Mt. Etna region, and to find the best place for continual radon monitoring using a permanent station in the near future. PMID:24729558

  9. DNA sequence of the Xenopus laevis mitochondrial heavy and light strand replication origins and flanking tRNA genes.

    PubMed Central

    Wong, J F; Ma, D P; Wilson, R K; Roe, B A

    1983-01-01

    We have determined the primary structure of the two regions of the Xenopus laevis mitochondrial genome which encompass the origins of heavy (H) and light (L) strand replication. The first segment, which consists of 2398 nucleotides, contains the displacement loop (D-loop), the tRNA genes for threonine, proline and phenylalanine, the origin of H-strand replication, and the promoters of H- and L-strand transcription. The second segment, which consists of 447 nucleotides, contains the L-strand replication origin flanked by the tRNA genes for tryptophan, alanine, asparagine, cysteine, and tyrosine. A comparison of the sequences of the Xenopus laevis mitochondrial L-strand replication origin region and the eight tRNA genes with their counterparts from the mammalian mitochondrial genomes reveals that these regions are quite homologous, while its D-loop region shows only slight homology with those of the mammalian mitochondrial genomes. PMID:6308566

  10. Weak, quasiparallel profiles of earth's bow shock - A comparison between numerical simulations and ISEE 3 observations on the far flank

    NASA Technical Reports Server (NTRS)

    Greenstadt, E. W.; Coroniti, F. V.; Moses, S. L.; Tsurutani, B. T.; Omidi, N.; Quest, K. B.; Krauss-Varban, D.

    1991-01-01

    Over 200 crossings of the distant downwind flanks of earth's magnetosonic bow shock by ISEE 3 included many cases of weak, or low Mach number, quasi-parallel shocks. A consistent feature of the magnetic field profiles was the presence of large amplitude, near periodic to irregular transverse oscillations downstream from even the weakest Q-parallel shocks. Large downstream perturbations with whistler-like features similar to those of the observations appear in 1D simulations when the Alfven Mach number M(A) is greater than 2.5 but not when M(A) = 2.1. The observed cases with downstream waves also occurred when M(A) is greater than about 2.5, suggesting the importance of the Alfven as opposed to magnetosonic Mach number in determining the signature of weak, Q-parallel shocks.

  11. Reconstructing past seawater Mg/Ca and Sr/Ca from mid-ocean ridge flank calcium carbonate veins.

    PubMed

    Coggon, Rosalind M; Teagle, Damon A H; Smith-Duque, Christopher E; Alt, Jeffrey C; Cooper, Matthew J

    2010-02-26

    Proxies for past seawater chemistry, such as Mg/Ca and Sr/Ca ratios, provide a record of the dynamic exchanges of elements between the solid Earth, the atmosphere, and the hydrosphere and the evolving influence of life. We estimated past oceanic Mg/Ca and Sr/Ca ratios from suites of 1.6- to 170-million-year-old calcium carbonate veins that had precipitated from seawater-derived fluids in ocean ridge flank basalts. Our data indicate that before the Neogene, oceanic Mg/Ca and Sr/Ca ratios were lower than in the modern ocean. Decreased ocean spreading since the Cretaceous and the resulting slow reduction in ocean crustal hydrothermal exchange throughout the early Tertiary may explain the recent rise in these ratios. PMID:20133522

  12. Shallow seismic imaging of flank collapse structures in oceanic island volcanoes: Application to the Western Canary Islands

    NASA Astrophysics Data System (ADS)

    Sanchez, L.; González, P.; Tiampo, K. F.

    2013-12-01

    Volcanic flank collapse counts among the many hazards associated with volcanic activity. This type of event involves the mobilization of large volumes, producing debris avalanches. It affects mostly oceanic island volcanoes, involving the potential for tsunami occurrence. Geophysical imaging can illuminate subvolcanic features such as volcano-tectonic structures, magmatic plumbing systems or differences in rock type. The most commonly used geophysical methods are gravity, electromagnetics and seismics. In particular, seismic measurements quantify anomalies in seismic waves propagation velocities and can be used to obtain information on the subsurface arrangement of different materials. In the Western Canary Islands, the Cumbre Vieja volcano in La Palma (Canary Islands) has been proposed to be near the collapse stage. Previous geophysical studies that have been carried out on the flank of the volcano comprise gravity and electromagnetic methods. These types of surveys gather information on the deep structures of the volcano (1-2 km). In this project, we complement previous studies by using seismic methods to investigate the near-surface seismic structure of the Cumbre Vieja fault system (La Palma Island) and the structure of the well-developed San Andres fault system (El Hierro Island). We aim to compare the Cumbre Vieja and San Andres fault systems to infer the degree of maturity of collapse structures. We carried out reflection and refraction seismic surveys in order to image approximately the first 10 meters of the subsurface. We used 24 low frequency (4,5 Hz) geophones as receivers and a sledge hammer as the seismic source. The survey lines were located across visible parts of the fault systems at the Cumbre Vieja volcano and the San Andres fault in El Hierro. Here, we present the survey setup and results from the preliminary analysis of the data.

  13. Impact of Bottom Trawling on Deep-Sea Sediment Properties along the Flanks of a Submarine Canyon

    PubMed Central

    Martín, Jacobo; Puig, Pere; Masqué, Pere; Palanques, Albert; Sánchez-Gómez, Anabel

    2014-01-01

    The offshore displacement of commercial bottom trawling has raised concerns about the impact of this destructive fishing practice on the deep seafloor, which is in general characterized by lower resilience than shallow water regions. This study focuses on the flanks of La Fonera (or Palamós) submarine canyon in the Northwestern Mediterranean, where an intensive bottom trawl fishery has been active during several decades in the 400–800 m depth range. To explore the degree of alteration of surface sediments (0–50 cm depth) caused by this industrial activity, fishing grounds and control (untrawled) sites were sampled along the canyon flanks with an interface multicorer. Sediment cores were analyzed to obtain vertical profiles of sediment grain-size, dry bulk density, organic carbon content and concentration of the radionuclide 210Pb. At control sites, surface sediments presented sedimentological characteristics typical of slope depositional systems, including a topmost unit of unconsolidated and bioturbated material overlying sediments progressively compacted with depth, with consistently high 210Pb inventories and exponential decaying profiles of 210Pb concentrations. Sediment accumulation rates at these untrawled sites ranged from 0.3 to 1.0 cm y−1. Sediment properties at most trawled sites departed from control sites and the sampled cores were characterized by denser sediments with lower 210Pb surface concentrations and inventories that indicate widespread erosion of recent sediments caused by trawling gears. Other alterations of the physical sediment properties, including thorough mixing or grain-size sorting, as well as organic carbon impoverishment, were also visible at trawled sites. This work contributes to the growing realization of the capacity of bottom trawling to alter the physical properties of surface sediments and affect the seafloor integrity over large spatial scales of the deep-sea. PMID:25111298

  14. Expression of the Human Glucokinase Gene: Important Roles of the 5′ Flanking and Intron 1 Sequences

    PubMed Central

    Li, Zhixin; Mao, Yiqing; Li, Hui; Wang, Xi; Wang, Rong; Xu, Wei; Song, Rongjing; Jin, Ling; Li, Xiuli; Irwin, David M.; Niu, Gang; Tan, Huanran

    2012-01-01

    Background Glucokinase plays important tissue-specific roles in human physiology, where it acts as a sensor of blood glucose levels in the pancreas, and a few other cells of the gut and brain, and as the rate-limiting step in glucose metabolism in the liver. Liver-specific expression is driven by one of the two tissue-specific promoters, and has an absolute requirement for insulin. The sequences that mediate regulation by insulin are incompletely understood. Methodology/Principal Findings To better understand the liver-specific expression of the human glucokinase gene we compared the structures of this gene from diverse mammals. Much of the sequence located between the 5′ pancreatic beta-cell-specific and downstream liver-specific promoters of the glucokinase genes is composed of repetitive DNA elements that were inserted in parallel on different mammalian lineages. The transcriptional activity of the liver-specific promoter 5′ flanking sequences were tested with and without downstream intronic sequences in two human liver cells lines, HepG2 and L-02. While glucokinase liver-specific 5′ flanking sequences support expression in liver cell lines, a sequence located about 2000 bases 3′ to the liver-specific mRNA start site represses gene expression. Enhanced reporter gene expression was observed in both cell lines when cells were treated with fetal calf serum, but only in the L-02 cells was expression enhanced by insulin. Conclusions/Significance Our results suggest that the normal liver L-02 cell line may be a better model to understand the regulation of the liver-specific expression of the human glucokinase gene. Our results also suggest that sequences downstream of the liver-specific mRNA start site have important roles in the regulation of liver-specific glucokinase gene expression. PMID:23029263

  15. Influence of substrate tectonic heritage on the evolution of composite volcanoes: Predicting sites of flank eruption, lateral collapse, and erosion

    NASA Astrophysics Data System (ADS)

    Tibaldi, Alessandro; Corazzato, Claudia; Kozhurin, Andrey; Lagmay, Alfredo F. M.; Pasquarè, Federico A.; Ponomareva, Vera V.; Rust, Derek; Tormey, Daniel; Vezzoli, Luigina

    2008-04-01

    This paper aims to aid understanding of the complicated interplay between construction and destruction of volcanoes, with an emphasis on the role of substrate tectonic heritage in controlling magma conduit geometry, lateral collapse, landslides, and preferential erosion pathways. The influence of basement structure on the development of six composite volcanoes located in different geodynamic/geological environments is described: Stromboli (Italy), in an island arc extensional tectonic setting, Ollagüe (Bolivia-Chile) in a cordilleran extensional setting, Kizimen (Russia) in a transtensional setting, Pinatubo (Philippines) in a transcurrent setting, Planchon (Chile) in a compressional cordilleran setting, and Mt. Etna (Italy) in a complex tectonic boundary setting. Analogue and numerical modelling results are used to enhance understanding of processes exemplified by these volcanic centres. We provide a comprehensive overview of this topic by considering a great deal of relevant, recently published studies and combine these with the presentation of new results, in order to contribute to the discussion on substrate tectonics and its control on volcano evolution. The results show that magma conduits in volcanic rift zones can be geometrically controlled by the regional tectonic stress field. Rift zones produce a lateral magma push that controls the direction of lateral collapse and can also trigger collapse. Once lateral collapse occurs, the resulting debuttressing produces a reorganization of the shallow-level magma migration pathways towards the collapse depression. Subsequent landslides and erosion tend to localize along rift zones. If a zone of weakness underlies a volcano, long-term creep can occur, deforming a large sector of the cone. This deformation can trigger landslides that propagate along the destabilized flank axis. In the absence of a rift zone, normal and transcurrent faults propagating from the substrate through the volcano can induce flank

  16. Identification and characterization of 5′-flanking region of the human riboflavin transporter 1 gene (SLC52A1)

    PubMed Central

    Sabui, Subrata; Ghosal, Abhisek; Said, Hamid M.

    2014-01-01

    The human SLC52A1 gene encodes the riboflavin transporter-1 (RFVT-1), a plasma membrane protein that transports vitamin B2 (riboflavin, RF) into cells, and thus, plays a role in controlling cellular homeostasis of RF in those tissues that express the carrier protein (e.g. placenta and intestine). Currently, there is nothing known about transcriptional regulation of the SLC52A1 gene, therefore, we aimed to clone and characterize its 5′-flanking region. Using rapid amplification of the cDNA ends (5′-RACE), we identified one transcription start site (TSS). A 579 bp segment of the 5′-flanking region of this gene was cloned which exhibited robust promoter activity upon transfection in human intestinal epithelial cells. Deletion analysis revealed the core promoter activity to be embedded in a region between −234 and −23 that lacked TATA element, was GC-rich, and harbored several putative cis-regulatory sites including KLFs, AP-2, EGRF and Sp-1. Mutating each of these sites led to a significant decrease in promoter activity (which was highest for the Sp-1 site), suggesting their possible involvement in regulating SLC52A1 transcription. Focusing on the Sp-1 site, EMSA, super-shift and ChIP analysis was performed that established the interaction of the Sp-1 transcription factor with the SLC52A1 promoter; also, co-transfection of the minimal SLC52A1 promoter with an Sp-1 containing vector in Drosophila SL-2 cells led to significant promoter activation. These results are the first to reveal the identity of the minimal SLC52A1 promoter and to establish an important role for Sp-1 in its activity. PMID:25284511

  17. Impact of bottom trawling on deep-sea sediment properties along the flanks of a submarine canyon.

    PubMed

    Martín, Jacobo; Puig, Pere; Masqué, Pere; Palanques, Albert; Sánchez-Gómez, Anabel

    2014-01-01

    The offshore displacement of commercial bottom trawling has raised concerns about the impact of this destructive fishing practice on the deep seafloor, which is in general characterized by lower resilience than shallow water regions. This study focuses on the flanks of La Fonera (or Palamós) submarine canyon in the Northwestern Mediterranean, where an intensive bottom trawl fishery has been active during several decades in the 400-800 m depth range. To explore the degree of alteration of surface sediments (0-50 cm depth) caused by this industrial activity, fishing grounds and control (untrawled) sites were sampled along the canyon flanks with an interface multicorer. Sediment cores were analyzed to obtain vertical profiles of sediment grain-size, dry bulk density, organic carbon content and concentration of the radionuclide 210Pb. At control sites, surface sediments presented sedimentological characteristics typical of slope depositional systems, including a topmost unit of unconsolidated and bioturbated material overlying sediments progressively compacted with depth, with consistently high 210Pb inventories and exponential decaying profiles of 210Pb concentrations. Sediment accumulation rates at these untrawled sites ranged from 0.3 to 1.0 cm y-1. Sediment properties at most trawled sites departed from control sites and the sampled cores were characterized by denser sediments with lower 210Pb surface concentrations and inventories that indicate widespread erosion of recent sediments caused by trawling gears. Other alterations of the physical sediment properties, including thorough mixing or grain-size sorting, as well as organic carbon impoverishment, were also visible at trawled sites. This work contributes to the growing realization of the capacity of bottom trawling to alter the physical properties of surface sediments and affect the seafloor integrity over large spatial scales of the deep-sea. PMID:25111298

  18. Storage conditions and eruptive dynamics of central versus flank eruptions in volcanic islands: The case of Tenerife (Canary Islands, Spain)

    NASA Astrophysics Data System (ADS)

    Andújar, Joan; Costa, Fidel; Scaillet, Bruno

    2013-06-01

    We report the results of phase equilibrium experiments on a phonolite produced during one of the most voluminous flank eruptions (ca. 1 km3) of the Teide-Pico Viejo complex (Tenerife Island). Combined with previous experimental and volcanological data we address the factors that control the structure of the phonolitic plumbing system of Teide-Pico Viejo stratovolcanoes. The Roques Blancos phonolite erupted ca 1800 BP and contains ~ 14 wt.% phenocrysts, mainly anorthoclase, biotite, magnetite, diopside and lesser amounts of ilmenite. Crystallization experiments were performed at temperatures of 900 °C, 850 °C and 800 °C, in the pressure range 200 MPa to 50 MPa. The oxygen fugacity (fO2) was varied between NNO + 0.3 (0.3 log units above to the Ni-NiO solid buffer) to NNO-2, whilst dissolved water contents varied from 7 wt.% to 1.5 wt.%. The comparison between natural and experimental phase proportions and compositions, including glass, indicates that the phonolite magma was stored prior to eruption at 900 ± 15 °C, 50 ± 15 MPa, with about 2.2 wt.% H2O dissolved in the melt, at an oxygen fugacity of NNO-0.5 (± 0.5). The difference in composition between the rim and the cores of the natural anorthoclase phenocrysts suggests that the phonolite was heated by about 50 °C before the eruption, upon intrusion of a hotter tephriphonolitic magma. The comparison between the storage conditions of Roques Blancos and those inferred for other phonolites of the Teide-Pico Viejo volcanic complex shows that flank eruptions are fed by reservoirs located at relatively shallow depths (1-2 km) compared to those feeding Teide central eruptions (5 km).

  19. Mapping of a gene for familial juvenile nephronophthisis: Refining the map and defining flanking markers on chromosome 2

    SciTech Connect

    Hildebrandt, F.; Singh-Sawhney, I.; Schnieders, B.; Centofante, L.; Omran, H.; Pohlmann, A.; Schmaltz, C.; Wedekind, H.; Schubotz, D.; Brandis, M. ); Antignac, C. ); Weber, J.L. )

    1993-12-01

    Familial juvenile nephronophthisis (NPH) is an autosomal recessive kidney disease that leads to end-stage renal failure in adolescence and is associated with the formation of cysts at the cortico-medullary junction of the kidneys. NPH is responsible for about 15% of end-stage renal disease in children, as shown by Kleinknecht and Habib. NPH in combination with autosomal recessive retinitis pigmentosa is known as the Senior-Loken syndrome (SLS) and exhibits renal pathology that is identical to NPH. The authors had excluded 40% of the human genome from linkage with a disease locus for NH or SLS when Antignac et al. first demonstrated linkage for an NPH locus on chromosome 2. The authors present confirmation of linkage of an NPH locus to microsatellite markers on chromosome 2 in nine families with NPH. By linkage analysis with marker AFM262xb5 at locus D2S176, a maximum lod score of 5.05 at a [theta][sub max] = .03 was obtained. In a large NPH family that yielded at D2S176 a maximum lod score of 2.66 at [theta][sub max] = .0, markers AFM172xc3 and AFM016yc5, representing loci D2S135 and D2S110, respectively, were identified as flanking markers, thereby defining the interval for an NPH locus to a region of approximately 15 cM. Furthermore, the cytogenetic assignment of the NPH region was specified to 2p12-(2q13 or adjacent bands) by calculation of linkage between these flanking markers and markers with known unique cytogenic assignment. The refined map may serve as a genetic framework for additional genetic and physical mapping of the region. 26 refs., 3 figs., 1 tab.

  20. Identification and characterization of 5'-flanking region of the human riboflavin transporter 1 gene (SLC52A1).

    PubMed

    Sabui, Subrata; Ghosal, Abhisek; Said, Hamid M

    2014-12-10

    The human SLC52A1 gene encodes the riboflavin transporter-1 (RFVT-1), a plasma membrane protein that transports vitamin B2 (riboflavin, RF) into cells, and thus, plays a role in controlling cellular homeostasis of RF in those tissues that express the carrier protein (e.g. placenta and intestine). Currently, there is nothing known about transcriptional regulation of the SLC52A1 gene, therefore, we aimed to clone and characterize its 5'-flanking region. Using rapid amplification of the cDNA ends (5'-RACE), we identified one transcription start site (TSS). A 579 bp segment of the 5'-flanking region of this gene was cloned which exhibited robust promoter activity upon transfection in human intestinal epithelial cells. Deletion analysis revealed that the core promoter activity to be embedded in a region between -234 and -23 that lacked TATA element, was GC-rich, and harbored several putative cis-regulatory sites including KLFs, AP-2, EGRF and Sp-1. Mutating each of these sites led to a significant decrease in promoter activity (which was highest for the Sp-1 site), suggesting their possible involvement in regulating SLC52A1 transcription. Focusing on the Sp-1 site, EMSA, super-shift and ChIP analysis was performed that established the interaction of the Sp-1 transcription factor with the SLC52A1 promoter; also, co-transfection of the minimal SLC52A1 promoter with an Sp-1 containing vector in Drosophila SL-2 cells led to significant promoter activation. These results are the first to reveal the identity of the minimal SLC52A1 promoter and to establish an important role for Sp-1 in its activity. PMID:25284511

  1. Flanking proline residues identify the L-type Ca2+ channel binding site of calciseptine and FS2.

    PubMed

    Kini, R M; Caldwell, R A; Wu, Q Y; Baumgarten, C M; Feher, J J; Evans, H J

    1998-06-23

    Calciseptine and FS2 are 60-amino acid polypeptides, isolated from venom of the black mamba (Dendroaspis polylepis polylepis), that block voltage-dependent L-type Ca2+ channels. We predicted that these polypeptides contain an identical functional site between residues 43 and 46 by searching for proline residues that mark the flanks of protein-protein interaction sites [Kini, R. M., and Evans, H. J. (1966) FEBS Lett. 385, 81-86]. The predicted Ca2+ channel binding site also occurs in closely related toxins, C10S2C2 and S4C8. Therefore, it is likely that these toxins also will block L-type Ca2+ channels. To test the proposed binding site on calciseptine and FS2, an eight-residue peptide, named L-calchin (L-type calcium channel inhibitor), was synthesized and examined for biological activity. As expected for an L-type Ca2+ channel blocker, L-calchin reduced peak systolic and developed pressure in isolated rat heart Langendorff preparations without affecting diastolic pressure or heart rate. Furthermore, L-calchin caused a voltage-independent block of L-type Ca2+ channel currents in whole-cell patch-clamped rabbit ventricular myocytes. Thus the synthetic peptide exhibits the L-type Ca2+ channel blocking properties of the parent molecules, calciseptine and FS2, but with a lower potency. These results strongly support the identification of a site in calciseptine and FS2 that is important for binding to L-type Ca2+ channels and reinforce the importance of proline brackets flanking protein-protein interaction sites. PMID:9636051

  2. Marine neotectonic investigation of the San Gregorio Fault Zone on the northern flank of Monterey Canyon, offshore central California

    NASA Astrophysics Data System (ADS)

    Maier, K. L.; Paull, C. K.; Brothers, D. S.; McGann, M.; Caress, D. W.; Lundsten, E. M.; Anderson, K.; Gwiazda, R.

    2014-12-01

    The San Gregorio Fault Zone (SGFZ) is part of the North American-Pacific plate boundary and is thought to accommodate right-lateral offset up to 10 mm/yr. Because much of the SGFZ in Monterey Bay, central California, lies offshore in steep submarine canyon bathymetry, little is known of its recent activity. We provide initial direct evidence for faulting where the SGFZ has been interpreted based on canyon morphology to cross the northern flank of Monterey Canyon. High-resolution multibeam bathymetry and chirp subbottom profiles were acquired during 13 dives with the Monterey Bay Aquarium Research Institute's (MBARI) Autonomous Underwater Vehicle (AUV) from 2009-2014 on the northern flank of Monterey Canyon, extending from the shelf edge ~15 km offshore Santa Cruz to ~1850 m water depth. Chirp profiles resolve layered sediments up to ~40 m subsurface in this region, and no fault scarps or seafloor lineaments are visible in the 1-m resolution multibeam bathymetry. At least one subsurface fault is identified within the SGFZ by offset reflections across a discrete, nearly vertical fault. However, this fault is only imaged where mass wasting has exhumed older strata to within ~25 m of the seafloor. Numerous slumps scars on the seafloor and packages of chaotic internal reflectivity in chirp profiles suggest that submarine landslide processes dominate the study area. To constrain the age of reflections offset by the fault, MBARI's Remotely Operated Vehicle (ROV) Doc Ricketts, sampled faces of slump scars where the offset reflections crop out using vibracores and horizontal push cores. Radiocarbon dating of foraminifera within these core samples is being used to constrain the last recorded movement on the fault. Application of AUV and ROV methods allows detailed neotectonic investigation of significant offshore structures, like the SGFZ, that contribute to hazard assessment.

  3. Effect of Saw Palmetto Supplements on Androgen-Sensitive LNCaP Human Prostate Cancer Cell Number and Syrian Hamster Flank Organ Growth.

    PubMed

    Opoku-Acheampong, Alexander B; Penugonda, Kavitha; Lindshield, Brian L

    2016-01-01

    Saw palmetto supplements (SPS) are commonly consumed by men with prostate cancer. We investigated whether SPS fatty acids and phytosterols concentrations determine their growth-inhibitory action in androgen-sensitive LNCaP cells and hamster flank organs. High long-chain fatty acids-low phytosterols (HLLP) SPS ≥ 750 nM with testosterone significantly increased and ≥500 nM with dihydrotestosterone significantly decreased LNCaP cell number. High long-chain fatty acids-high phytosterols (HLHP) SPS ≥ 500 nM with dihydrotestosterone and high medium-chain fatty acids-low phytosterols (HMLP) SPS ≥ 750 nM or with androgens significantly decreased LNCaP cell number (n = 3; p < 0.05). Five- to six-week-old, castrated male Syrian hamsters were randomized to control (n = 4), HLLP, HLHP, and HMLP SPS (n = 6) groups. Testosterone or dihydrotestosterone was applied topically daily for 21 days to the right flank organ; the left flank organ was treated with ethanol and served as the control. Thirty minutes later, SPS or ethanol was applied to each flank organ in treatment and control groups, respectively. SPS treatments caused a notable but nonsignificant reduction in the difference between left and right flank organ growth in testosterone-treated SPS groups compared to the control. The same level of inhibition was not seen in dihydrotestosterone-treated SPS groups (p < 0.05). Results may suggest that SPS inhibit 5α-reductase thereby preventing hamster flank organ growth. PMID:27272436

  4. Radiation therapy for favorable histology Wilms tumor: Prevention of flank recurrence did not improve survival on National Wilms Tumor Studies 3 and 4

    SciTech Connect

    Breslow, Norman E. . E-mail: norm@u.washington.edu; Beckwith, J. Bruce; Haase, Gerald M.; Kalapurakal, John A.; Ritchey, Michael L.; Shamberger, Robert C.; Thomas, Patrick; D'Angio, Giulio J.; Green, Daniel M.

    2006-05-01

    Purpose: To determine whether radiation therapy (RT) of patients with Wilms tumor of favorable histology prevented flank recurrence and thereby improved the survival outcomes. Methods and Materials: Recurrence and mortality risks were compared among groups of patients with Stage I-IV/favorable histology Wilms tumor enrolled in the third (n = 1,640) and fourth (n = 2,066) National Wilms Tumor Study Group studies. Results: Proportions of patients with flank recurrence were 0 of 513 = 0.0% for 20 Gy, 12 of 805 = 1.5% for 10 Gy, and 44 of 2,388 = 1.8% for no flank RT (p trend 0.001 adjusted for stage and doxorubicin); for intra-abdominal (including flank) recurrence they were 5 of 513 = 1.0%, 30 of 805 = 3.7%, and 58 of 2,388 = 2.4%, respectively (p trend = 0.02 adjusted). Survival percentages at 8 years after intra-abdominal recurrence were 0 of 5 = 0% for 20 Gy, 10 of 30 = 33% for 10 Gy, and 34 of 58 = 56% for no RT (p trend = 0.0001). NWTS-4 discontinued use of 20 Gy RT, and the 8-year flank recurrence risk increased to 2.1% from 1.0% on NWTS-3 (p = 0.013). However, event-free survival was unaltered (88% vs. 86%, p = 0.39), and overall survival was better (93.8% vs. 90.8%, p = 0.036) on NWTS-4. Conclusions: Partly because of lower postrecurrence mortality among nonirradiated patients, prevention of flank recurrence by RT did not improve survival. It is important to evaluate entire treatment policies with regard to long-term outcomes.

  5. Effect of Saw Palmetto Supplements on Androgen-Sensitive LNCaP Human Prostate Cancer Cell Number and Syrian Hamster Flank Organ Growth

    PubMed Central

    Opoku-Acheampong, Alexander B.; Penugonda, Kavitha; Lindshield, Brian L.

    2016-01-01

    Saw palmetto supplements (SPS) are commonly consumed by men with prostate cancer. We investigated whether SPS fatty acids and phytosterols concentrations determine their growth-inhibitory action in androgen-sensitive LNCaP cells and hamster flank organs. High long-chain fatty acids-low phytosterols (HLLP) SPS ≥ 750 nM with testosterone significantly increased and ≥500 nM with dihydrotestosterone significantly decreased LNCaP cell number. High long-chain fatty acids-high phytosterols (HLHP) SPS ≥ 500 nM with dihydrotestosterone and high medium-chain fatty acids-low phytosterols (HMLP) SPS ≥ 750 nM or with androgens significantly decreased LNCaP cell number (n = 3; p < 0.05). Five- to six-week-old, castrated male Syrian hamsters were randomized to control (n = 4), HLLP, HLHP, and HMLP SPS (n = 6) groups. Testosterone or dihydrotestosterone was applied topically daily for 21 days to the right flank organ; the left flank organ was treated with ethanol and served as the control. Thirty minutes later, SPS or ethanol was applied to each flank organ in treatment and control groups, respectively. SPS treatments caused a notable but nonsignificant reduction in the difference between left and right flank organ growth in testosterone-treated SPS groups compared to the control. The same level of inhibition was not seen in dihydrotestosterone-treated SPS groups (p < 0.05). Results may suggest that SPS inhibit 5α-reductase thereby preventing hamster flank organ growth. PMID:27272436

  6. Hinf I/Tsp509 I and BsoF I polymorphisms in the flanking regions of the human VNTR locus D1S80.

    PubMed

    Duncan, G T; Balamurugan, K; Budowle, B; Tracey, M L

    1996-11-01

    The minisatellite locus D1S80 (1p35-p36), is a highly polymorphic VNTR that also contains a Hinf I polymorphism in the 5' flanking region. Our data suggest that the Hinf I polymorphism is a G > T transversion 58 bases downstream from the forward primer. This G > T transversion also creates a Tsp509 I restriction site. Additionally, a G > C transversion polymorphism was identified in the 3' flanking region by the creation of a BsoF I restriction site immediately adjacent to the repeat region. PMID:9021400

  7. Successful fabrication of a convex platform PMMA cell-counting slide using a high-precision perpendicular dual-spindle CNC machine tool

    NASA Astrophysics Data System (ADS)

    Chen, Shun-Tong; Chang, Chih-Hsien

    2013-12-01

    This study presents a novel approach to the fabrication of a biomedical-mold for producing convex platform PMMA (poly-methyl-meth-acrylate) slides for counting cells. These slides allow for the microscopic examination of urine sediment cells. Manufacturing of such slides incorporates three important procedures: (1) the development of a tabletop high-precision dual-spindle CNC (computerized numerical control) machine tool; (2) the formation of a boron-doped polycrystalline composite diamond (BD-PCD) wheel-tool on the machine tool developed in procedure (1); and (3) the cutting of a multi-groove-biomedical-mold array using the formed diamond wheel-tool in situ on the developed machine. The machine incorporates a hybrid working platform providing wheel-tool thinning using spark erosion to cut, polish, and deburr microgrooves on NAK80 steel directly. With consideration given for the electrical conductive properties of BD-PCD, the diamond wheel-tool is thinned to a thickness of 5 µm by rotary wire electrical discharge machining. The thinned wheel-tool can grind microgrooves 10 µm wide. An embedded design, which inserts a close fitting precision core into the biomedical-mold to create step-difference (concave inward) of 50 µm in height between the core and the mold, is also proposed and realized. The perpendicular dual-spindles and precision rotary stage are features that allow for biomedical-mold machining without the necessity of uploading and repositioning materials until all tasks are completed. A PMMA biomedical-slide with a plurality of juxtaposed counting chambers is formed and its usefulness verified.

  8. Dynamic Spin Rig Upgraded With a Five- Axis-Controlled Three-Magnetic-Bearing Support System With Forward Excitation

    NASA Technical Reports Server (NTRS)

    Morrison, Carlos R.; Mehmed, Oral

    2003-01-01

    The NASA Glenn Research Center Dynamic Spin Rig is used for experimental evaluation of vibration analysis methods and dynamic characteristics for rotating systems. Measurements are made while rotors are spun and vibrated in a vacuum chamber. The rig has been upgraded with a new active magnetic bearing rotor support and excitation system. This design is expected to provide operational improvements over the existing rig. The rig will be able to be operated in either the old or new configuration. In the old configuration, two ball bearings support the vertical shaft of the rig, with the test article located between the bearings. Because the bearings operate in a vacuum, lubrication is limited to grease. This limits bearing life and speed. In addition, the old configuration employs two voice-coil electromagnetic shakers to apply oscillatory axial forces or transverse moments to the rotor shaft through a thrust bearing. The excitation amplitudes that can be imparted to the test article with this system are not adequate for components that are highly damped. It is expected that the new design will overcome these limitations.

  9. Surface-figuring CVD-SiC mirrors with a five-axis-control ultraprecision grinding machine

    NASA Astrophysics Data System (ADS)

    Namba, Yoshiharu; Suzuki, Hiroshi

    1997-11-01

    A large 5-axis control ultraprecision grinding machine has been developed for making synchrotron-radiation mirrors with high accuracy. The positional and angular resolutions of the machine are 10 nm and 0.0002 degree, respectively. The dimensions of the machine are 3.3 m by 2.7 m by 4.4 m in height. The machine can generate non-axisymmetric aspheric surfaces on CVD-SiC material by a disc-type metal-bonded diamond wheel. An electric micrometer has been set near a grinding head for measuring the form error of ground surface in conformity with the machine movement due to the cutter location data. A series of the measured form errors corrects the former cutter location data automatically and the next grinding operation will be performed by the new cutter location data. A CVD-SiC material of 510 mm by 110 mm was ground into a toroidal surface of 750 nm in shape accuracy by the fifth grinding operation with the fourth correction of cutter location data. More than 99% of toroidal surface area have a form accuracy less than 500 nm. 3.3 nm rms surface roughness was obtained by the ultraprecision grinding using a SD4000N150M metal-bonded diamond wheel.

  10. Leakage of active crater lake brine through the north flank at Rincon de la Vieja volcano, northwest Costa Rica, and implications for crater collapse

    USGS Publications Warehouse

    Kempter, K.A.; Rowe, G.L.

    2000-01-01

    The Active Crater at Rincon de la Vieja volcano, Costa Rica, reaches an elevation of 1750 m and contains a warm, hyper-acidic crater lake that probably formed soon after the eruption of the Rio Blanco tephra deposit approximately 3500 years before present. The Active Crater is buttressed by volcanic ridges and older craters on all sides except the north, which dips steeply toward the Caribbean coastal plains. Acidic, above-ambient-temperature streams are found along the Active Crater's north flank at elevations between 800 and 1000 m. A geochemical survey of thermal and non-thermal waters at Rincon de la Vieja was done in 1989 to determine whether hyper-acidic fluids are leaking from the Active Crater through the north flank, affecting the composition of north-flank streams. Results of the water-chemistry survey reveal that three distinct thermal waters are found on the flanks of Rincon de la Vieja volcano: acid chloride-sulfate (ACS), acid sulfate (AS), and neutral chloride (NC) waters. The most extreme ACS water was collected from the crater lake that fills the Active Crater. Chemical analyses of the lake water reveal a hyper-acidic (pH ~ 0) chloride-sulfate brine with elevated concentrations of calcium, magnesium, aluminum, iron, manganese, copper, zinc, fluorine, and boron. The composition of the brine reflects the combined effects of magmatic degassing from a shallow magma body beneath the Active Crater, dissolution of andesitic volcanic rock, and evaporative concentration of dissolved constituents at above-ambient temperatures. Similar cation and anion enrichments are found in the above-ambient-temperature streams draining the north flank of the Active Crater. The pH of north-flank thermal waters range from 3.6 to 4.1 and chloride:sulfate ratios (1.2-1.4) that are a factor of two greater than that of the lake brine (0.60). The waters have an ACS composition that is quite different from the AS and NC thermal waters that occur along the southern flank of Rincon

  11. Window into Sediment-Buried Basement Biosphere: Fluid Sampling from CORK Observatory Seafloor Platforms, Juan de Fuca Ridge Flanks

    NASA Astrophysics Data System (ADS)

    Cowen, J. P.; Lin, H.; Rappe, M.; Jungbluth, S.; Glazer, B. T.; Matzinger, M.; Amend, J. P.; Boettger, J.

    2010-12-01

    Studies of the deep basement biosphere are technologically challenging, requiring complementary approaches to provide sufficient access to allow precision analyses and experimentation. Our NSF-funded ‘Microbial Observatory’ has focused on IODP Circulation Obviating Retrofit Kit (CORK) observatories to obtain pristine samples of fluids from sediment-buried basement environments. We have developed instruments and samplers to interface with CORK fluid delivery lines, including a ROV/HOV-borne Mobile Pumping System and autonomous (e.g., GeoMICROBE) instrument sensor/sampler systems. These systems are providing high quality (e.g., depleted Mg++, <6 mM) samples of basement fluids from 3.5 mA old upper basement, on the flanks of the Juan de Fuca Ridge, for geochemical and microbial studies. Relative to bottom seawater, these fluids are also depleted in O2, SO42-, PO43-, NO3- and NO2-, while enriched in NH4+, H2S, Mn and Fe. In situ voltammetric analyses obtained during sample collection, revealed the presence of micromolar levels of sulfide (0.5 µm) in the fluids. Dissolved organic carbon in basement fluids is about half that of local bottom seawater, low molecular weight organic acids are below detection limits, while total amino acids are also low in concentration, but the relative abundance of specific amino acids varies from that of bottom seawater. Overall, the sediment-buried basement environments appears to be organic-carbon depleted and low energy, yet still dynamic. The microbial communities from CORK 1301A (47deg 45N, 127deg 45W) in consecutive years are heterogeneous, but share common groups. Different CORKs sampled a decade apart share major lineages, consistent with hydrogeologic connectivity. Samples collected from a new CORK installation at borehole 1026B contain a subset of members found a decade previously from an older style CORK at the same site. Communities retrieved from the CORK at 1025C (47deg 53N, 128deg 39W), in 1.4 My ridge flank basement

  12. Preliminary Mineralogic and Stable Isotope Studies of Altered Summit and Flank Rocks and Osceola Mudflow Deposits on Mount Rainier, Washington

    USGS Publications Warehouse

    Rye, Robert O.; Breit, George N.; Zimbelman, David R.

    2003-01-01

    About 5600 years ago part of Mount Rainier?s edifice collapsed with the resultant Osceola Mudflow traveling more than 120 km and covering an area of at least 505 km2. Mineralogic and stable isotope studies were conducted on altered rocks from outcrops near the summit and east flank of the volcano and samples of clasts and matrix from the Osceola Mudflow. Results of these analyses are used to constrain processes responsible for pre-collapse alteration and provide insight into the role of alteration in edifice instability prior to the Osceola collapse event. Jarosite, pyrite, alunite, and kaolinite occur in hydrothermally altered rock exposed in summit scarps formed by edifice collapse events and in altered rock within the east-west structural zone (EWSZ) of the volcano?s east flank. Deposits of the Osceola Mudflow contain clasts of variably altered and unaltered andesite within a clay-rich matrix. Minerals detected in samples from the edifice are also present in many of the clasts. The matrix includes abundant smectite, kaolinite and variably abundant jarosite. Hydrothermal fluid compositions calculated from hydrogen and oxygen isotope data of alunite, and smectite on Mount Rainier reflect mixing of magmatic and meteoric waters. The range in the dD values of modern meteoric water on the volcano (-85 to 155?) reflect the influence of elevation on the dD of precipitation. The d34S and d18OSO4 values of alunite, gypsum and jarosite are distinct but together range from 1.7 to 17.6? and -12.3 to 15.0?, respectively; both parameters increase from jarosite to gypsum to alunite. The variations in sulfur isotope composition are attributed to the varying contributions of disproportionation of magmatic SO2, the supergene oxidation of hydrothermal pyrite and possible oxidation of H2S to the parent aqueous sulfate. The 18OSO4 values of jarosite are the lowest recorded for the mineral, consistent with a supergene origin. The mineralogy and isotope composition of alteration

  13. Improving the efficiency of polymer solar cells based on furan-flanked diketopyrrolopyrrole copolymer via solvent additive and methanol treatment

    NASA Astrophysics Data System (ADS)

    Zhou, Weilong; Chen, Huajie; Lv, Junjie; Chen, Youchun; Zhang, Weifeng; Yu, Gui; Li, Fenghong

    2015-09-01

    We present a furan-flanked DPP copolymer, poly{3,6-difuran-2-yl-2,5-di(2-octyldodecyl)-pyrrolo [3,4-c]pyrrole-1,4-dione-altthienylenevinylene} (PDVF-8), and highlight the improvement in the power conversion efficiency (PCE) of polymer solar cells (PSCs) based on the PDVF-8 as an electron donor via solvent additive and methanol treatment. When 3 vol% 1,8-diiodooctane (DIO) or 1-chloronaphthalene (CN) were used as a solvent additive to the PDVF-8:PC71BM solution in chloroform (CF), the PCE can increase from 0.79% to 3.73% or 4.26%. Methanol treatment (MT) can further enhance the PCE to 4.03% (DIO) and 4.69% (CN). The effect of the solvent additives (DIO and CN) and MT on the phase separation of the PDVF-8:PC71BM thin film has been investigated in detail using atomic force microscopy, transmission electron microscopy (TEM), TEM-energy dispersive spectroscopy and X-ray photoemission spectroscopy depth profiling.We present a furan-flanked DPP copolymer, poly{3,6-difuran-2-yl-2,5-di(2-octyldodecyl)-pyrrolo [3,4-c]pyrrole-1,4-dione-altthienylenevinylene} (PDVF-8), and highlight the improvement in the power conversion efficiency (PCE) of polymer solar cells (PSCs) based on the PDVF-8 as an electron donor via solvent additive and methanol treatment. When 3 vol% 1,8-diiodooctane (DIO) or 1-chloronaphthalene (CN) were used as a solvent additive to the PDVF-8:PC71BM solution in chloroform (CF), the PCE can increase from 0.79% to 3.73% or 4.26%. Methanol treatment (MT) can further enhance the PCE to 4.03% (DIO) and 4.69% (CN). The effect of the solvent additives (DIO and CN) and MT on the phase separation of the PDVF-8:PC71BM thin film has been investigated in detail using atomic force microscopy, transmission electron microscopy (TEM), TEM-energy dispersive spectroscopy and X-ray photoemission spectroscopy depth profiling. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr04393j

  14. Platypus globin genes and flanking loci suggest a new insertional model for beta-globin evolution in birds and mammals

    PubMed Central

    Patel, Vidushi S; Cooper, Steven JB; Deakin, Janine E; Fulton, Bob; Graves, Tina; Warren, Wesley C; Wilson, Richard K; Graves, Jennifer AM

    2008-01-01

    Background Vertebrate alpha (α)- and beta (β)-globin gene families exemplify the way in which genomes evolve to produce functional complexity. From tandem duplication of a single globin locus, the α- and β-globin clusters expanded, and then were separated onto different chromosomes. The previous finding of a fossil β-globin gene (ω) in the marsupial α-cluster, however, suggested that duplication of the α-β cluster onto two chromosomes, followed by lineage-specific gene loss and duplication, produced paralogous α- and β-globin clusters in birds and mammals. Here we analyse genomic data from an egg-laying monotreme mammal, the platypus (Ornithorhynchus anatinus), to explore haemoglobin evolution at the stem of the mammalian radiation. Results The platypus α-globin cluster (chromosome 21) contains embryonic and adult α- globin genes, a β-like ω-globin gene, and the GBY globin gene with homology to cytoglobin, arranged as 5'-ζ-ζ'-αD-α3-α2-α1-ω-GBY-3'. The platypus β-globin cluster (chromosome 2) contains single embryonic and adult globin genes arranged as 5'-ε-β-3'. Surprisingly, all of these globin genes were expressed in some adult tissues. Comparison of flanking sequences revealed that all jawed vertebrate α-globin clusters are flanked by MPG-C16orf35 and LUC7L, whereas all bird and mammal β-globin clusters are embedded in olfactory genes. Thus, the mammalian α- and β-globin clusters are orthologous to the bird α- and β-globin clusters respectively. Conclusion We propose that α- and β-globin clusters evolved from an ancient MPG-C16orf35-α-β-GBY-LUC7L arrangement 410 million years ago. A copy of the original β (represented by ω in marsupials and monotremes) was inserted into an array of olfactory genes before the amniote radiation (>315 million years ago), then duplicated and diverged to form orthologous clusters of β-globin genes with different expression profiles in different lineages. PMID:18657265

  15. Cloning of insertion site flanking sequence and construction of transfer DNA insert mutant library in Stylosanthes colletotrichum.

    PubMed

    Chen, Helong; Hu, Caiping; Yi, Kexian; Huang, Guixiu; Gao, Jianming; Zhang, Shiqing; Zheng, Jinlong; Liu, Qiaolian; Xi, Jingen

    2014-01-01

    Stylosanthes sp. is the most important forage legume in tropical areas worldwide. Stylosanthes anthracnose, which is mainly caused by Colletotrichum gloeosporioides, is a globally severe disease in stylo production. Little progress has been made in anthracnose molecular pathogenesis research. In this study, Agrobacterium tumefaciens-mediated transformation was used to transform Stylosanthes colletotrichum strain CH008. The major factors of the genetic transformation system of S. colletotrichum were optimized as follows: A. tumefaciens' AGL-1 concentration (OD(600)), 0.8; concentration of Colletotrichum conidium, 1 × 10(6) conidia/mL; acetosyringone concentration, 100 mmol/L; induction time, 6 h; co-culture temperature, 25 °C; and co-culture time, 3 d. Thus, the transformation efficiency was increased to 300-400 transformants per 106 conidia. Based on the optimized system, a mutant library containing 4616 mutants was constructed, from which some mutants were randomly selected for analysis. Results show that the mutants were single copies that could be stably inherited. The growth rate, spore amount, spore germination rate, and appressorium formation rate in some mutants were significantly different from those in the wild-type strain. We then selected the most appropriate method for the preliminary screening and re-screening of each mutant's pathogenic defects. We selected 1230 transformants, and obtained 23 strains with pathogenic defects, namely, 18 strains with reduced pathogenicity and five strains with lost pathogenicity. Thermal asymmetric interlaced PCR was used to identify the transfer DNA (T-DNA) integration site in the mutant that was coded 2430, and a sequence of 476 bp was obtained. The flanking sequence of T-DNA was compared with the Colletotrichum genome by BLAST, and a sequence of 401 bp was found in Contig464 of the Colletotrichum genome. By predicting the function of the flanking sequence, we discovered that T-DNA insertion in the promoter region

  16. Transcription of a Drosophila tRNAArg gene in yeast extract: 5'-flanking sequence dependence for transcription in a heterologous system.

    PubMed Central

    Schaack, J; Söll, D

    1985-01-01

    The Drosophila tRNA gene encoded on pArg is efficiently transcribed in extracts of Saccharomyces cerevisiae, but the efficiency is 5'-flanking sequence dependent: deletion to between positions -21 and -17 (relative to position +1 of the mature coding sequence) reduces transcription to a very low level. This demonstrates that requirement for wild-type 5'-flanking sequence exists in the case of a heterologous combination of a tRNA gene and transcription extract. Expression of pArg in vivo in S. cerevisiae is also dependent on the wild-type 5'-flanking sequence, but only with deletion to between -17 and -11 is the steady-state level of pArg transcripts reduced to near zero. The 5'-flanking sequence requirement in S. cerevisiae extract is similar to that found in Drosophila Kc cell extract. However, transcription kinetics distinguish S. cerevisiae extract from that of Drosophila Kc cells. tRNA genes added to S. cerevisiae extract exhibit a lag phase before initiation of active transcription, but this lag is much shorter and much less temperature dependent than is the lag phase in Drosophila Kc cell extract. Images PMID:3889849

  17. Role of flanking sequences and phosphorylation in the recognition of the simian-virus-40 large T-antigen nuclear localization sequences by importin-alpha.

    PubMed Central

    Fontes, Marcos R M; Teh, Trazel; Toth, Gabor; John, Anna; Pavo, Imre; Jans, David A; Kobe, Bostjan

    2003-01-01

    The nuclear import of simian-virus-40 large T-antigen (tumour antigen) is enhanced via phosphorylation by the protein kinase CK2 at Ser112 in the vicinity of the NLS (nuclear localization sequence). To determine the structural basis of the effect of the sequences flanking the basic cluster KKKRK, and the effect of phosphorylation on the recognition of the NLS by the nuclear import factor importin-alpha (Impalpha), we co-crystallized non-autoinhibited Impalpha with peptides corresponding to the phosphorylated and non-phosphorylated forms of the NLS, and determined the crystal structures of the complexes. The structures show that the amino acids N-terminally flanking the basic cluster make specific contacts with the receptor that are distinct from the interactions between bipartite NLSs and Impalpha. We confirm the important role of flanking sequences using binding assays. Unexpectedly, the regions of the peptides containing the phosphorylation site do not make specific contacts with the receptor. Binding assays confirm that phosphorylation does not increase the affinity of the T-antigen NLS to Impalpha. We conclude that the sequences flanking the basic clusters in NLSs play a crucial role in nuclear import by modulating the recognition of the NLS by Impalpha, whereas phosphorylation of the T-antigen enhances nuclear import by a mechanism that does not involve a direct interaction of the phosphorylated residue with Impalpha. PMID:12852786

  18. East flank of the Sibumasu block in NW Thailand and Myanmar and its possible northward continuation into Yunnan: a review and suggested tectono-stratigraphic interpretation

    NASA Astrophysics Data System (ADS)

    Ridd, Michael F.

    2015-05-01

    The east flank of the Sibumasu block was a passive continental margin, and in NW Thailand is marked by the absence of the autochthonous Middle Permian-Triassic platform carbonates which are widespread across the rest of Sibumasu further west. Instead, the carbonates are represented by hemipelagic cherts, mudstones and sandstones including turbidites. During the northward drift of Sibumasu, following its Early Permian rifting from Gondwana, an accretionary complex was present where Palaeotethyan pelagic rocks as old as Devonian were subducted beneath the Sukhothai volcanic arc. At the time of Sibumasu's collision with the Sukhothai arc, beginning in the Middle Triassic, the accretionary complex was thrust westwards across the east flank of Sibumasu. It is suggested that in the Late Triassic the thrust pile which had been the accretionary complex underwent erosion and was the source of terrigenous clastic rocks deposited further west in a foredeep basin. The boundary of Sibumasu's east flank with the Permo-Triassic carbonate platform further west is the arcuate Mae Ping-Nam Teng Fault system. Notwithstanding later Cenozoic strike-slip displacement, those faults (as well as the Mae Yuam Fault) are interpreted to have had an earlier history of westward-directed Indosinian thrusting. Northwards in Myanmar and Yunnan the Sibumasu Permo-Triassic carbonate shelf continues as the Shan Plateau and Baoshan Block. The east flank is represented by the Changning-Menglian Belt, and the Palaeotethys 'cryptic suture' in Thailand possibly joins with the Lancangjiang Suture.

  19. The transition from summit to flank activity at Mt. Etna, Sicily (Italy): Inferences from the petrology of products erupted in 2007-2009

    NASA Astrophysics Data System (ADS)

    Corsaro, Rosa Anna; Miraglia, Lucia

    2014-04-01

    Mt. Etna is an active basaltic volcano where both flank and summit eruptions take place. In recent decades, the South-East summit crater (SEC) has in particular been characterized by 'episodic' eruptions, consisting of recurrent lava fountains associated with lava flow emissions and lasting from a few weeks to months. Recent volcanic activity shows that, if there is a transition from an episodic summit eruption to a flank eruption, then this usually takes place while the last paroxysm of the episodic eruption is still underway. By contrast, the 2007-08 episodic eruption at SEC was followed by the 2008-09 flank activity which started three days after the conclusion of the last paroxysm, coinciding with the strong earthquake (M = 7.9) in Sichuan (China), whose perturbations were recorded by the monitoring network of Mt. Etna. We therefore investigated the transition from a summit episodic eruption at SEC to flank activity utilizing a petrologic study of the products erupted from 2007 to 2009, integrated with literature data. The compositional variability of the products may largely be explained by a mixing between an evolved magma stored in the SEC reservoir and a more primitive magma which intrudes it. In the studied period, the most significant episodes of magma recharge occurred before the onset of the 2007-08 episodic eruption and during the 2008-09 flank activity, more precisely before June 2008. According to previous studies, the seven paroxysms of the 2007-08 episodic eruption at SEC have been interpreted as resulting from the disruption of a foam layer at the top of the SEC reservoir which was rebuilt before each subsequent episode. The transition from the 2007-08 episodic eruption at SEC to the 2008-09 flank activity was essentially triggered by the Sichuan earthquake which caused a variation of dynamic stress. It caused the volatile exolution, the pressurization of SEC stored magma, and the consequent fracturing of the surrounding rocks where magma intruded

  20. The transition summit-flank activity at Mt. Etna, Sicily (Italy): inferences from the petrology of products erupted from 2007 to 2009

    NASA Astrophysics Data System (ADS)

    Corsaro, Rosa Anna; Miraglia, Lucia

    2014-05-01

    Mt. Etna is an active basaltic volcano where both flank and summit eruptions take place. In particular, the South-East summit crater (SEC) during the last decades has been characterized by 'episodic' eruptions, which consist of recurrent lava fountains associated with lava flows emission, lasting from a few weeks to months. The past recent volcanic activity has shown that, if a transition from an episodic summit eruption to a flank eruption occurred, it generally took place while the last paroxysm of the episodic eruption was still underway. Differently, the 2007-08 episodic eruption at SEC was followed by the 2008-09 flank activity which started three days after the conclusion of the last paroxysm, in coincidence with the strong earthquake (M= 7.9) in Sichuan (China), whose perturbations have been registered by the monitoring network of Mt. Etna. We then investigated the transition from summit episodic activity at SEC to flank eruption utilizing a petrologic study of the products erupted from 2007 to 2009 integrated with data from the literature. The compositional variability of the products is mainly explainable with a mixing between an evolved magma stored in the SEC reservoir and a more primitive magma which intrudes it. In the studied period the most significant episodes of magma recharge occurred before the onset of the 2007-08 episodic activity and during the 2008-09 flank eruption, more precisely before June 2008. According to previous studies the seven episodes of the 2007-08 eruption at SEC have been interpreted to result from the disruption of a foam layer at the top of the SEC reservoir which was rebuilt before each subsequent episode. The transition from 2007-08 episodic eruption at SEC to the 2008-09 flank activity was essentially triggered by the Sichuan earthquake which caused a variation of dynamic stress. It promoted the volatile exolution, the pressurization of SEC stored magma, and the consequent fracturing of the surrounding rocks where magma

  1. Composition, geometry, and emplacement dynamics of a large volcanic island landslide offshore Martinique: From volcano flank-collapse to seafloor sediment failure?

    NASA Astrophysics Data System (ADS)

    Brunet, Morgane; Le Friant, Anne; Boudon, Georges; Lafuerza, Sara; Talling, Peter; Hornbach, Matthew; Ishizuka, Osamu; Lebas, Elodie; Guyard, Hervé

    2016-03-01

    Landslides are common features in the vicinity of volcanic islands. In this contribution, we investigate landslides emplacement and dynamics around the volcanic island of Martinique based on the first scientific drilling of such deposits. The evolution of the active Montagne Pelée volcano on this island has been marked by three major flank-collapses that removed much of the western flank of the volcano. Subaerial collapse volumes vary from 2 to 25 km3 and debris avalanches flowed into the Grenada Basin. High-resolution seismic data (AGUADOMAR-1999, CARAVAL-2002, and GWADASEIS-2009) is combined with new drill cores that penetrate up to 430 m through the three submarine landslide deposits previously associated to the aerial flank-collapses (Site U1399, Site U1400, Site U1401, IODP Expedition 340, Joides Resolution, March-April 2012). This combined geophysical and core data provide an improved understanding of landslide processes offshore a volcanic island. The integrated analysis shows a large submarine landslide deposit, without debris avalanche deposits coming from the volcano, comprising up to 300 km3 of remobilized seafloor sediment that extends for 70 km away from the coast and covers an area of 2100 km2. Our new data suggest that the aerial debris avalanche deposit enter the sea but stop at the base of submarine flank. We propose a new model dealing with seafloor sediment failures and landslide propagation mechanisms, triggered by volcanic flank-collapse events affecting Montagne Pelée volcano. Newly recognized landslide deposits occur deeper in the stratigraphy, suggesting the recurrence of large-scale mass-wasting processes offshore the island and thus, the necessity to better assess the associated tsunami hazards in the region.

  2. Temporal Evolution of Volcanic Eruption, Fluvial Drainage Systems and Faulting on the Northwest Flank of Alba Patera as Revealed by Photogeological Mapping

    NASA Astrophysics Data System (ADS)

    Chowdhury, Diya

    2013-01-01

    Although Alba Patera is the largest volcano in aerial extent in the solar system (˜6.8 km high and >1000 km in radius), the geologic processes responsible for shaping its exceedingly low-angle flanks remain poorly constrained. These flanks are covered in lava flows, valleys and both radial and annular grabens. Previous attempts, limited by the resolution of the satellite images, assume that the annular grabens formed during the terminal stage of volcanic development whereas surface water flow occurred in the early stage of volcanic construction. In this study, we analyze high-resolution CTX satellite images in conjunction with digital topographic data from MOLA. Our work reveals complex cross cutting relationships between faults, drainage network development and lava flows on the northwestern flank of Alba Patera. We observe a minimum of three generations of lava flows, three generations of drainage channels and three generations of faults. Mutual and successive cross-cutting relationships between drainage channels and faults indicate that the tectonic processes responsible for creating grabens on the volcano flank operated continuously and were coeval with drainage formation. The lava flows are observed to be the oldest geomorphic features and the third generation of faults as the youngest geomorphic features in our mapped region. Crater counting indicates that the surface within the mapped region is Amazonian in age. An analysis of the crater densities reveals a decline in crater densities from the south to the north section of the mapped region. This could be attributed to resurfacing in the north due to sediments deposited by northward flowing drainage channels. Crater counting age estimates for the south section yield a result of ˜ 1.74 Ga, +/- 0.12 Ga and ˜ 1.35 Ga, +/- 0.26 Ga for the north section. Hence, the younger age estimates of the northern surface could help further constrain the age of the drainage channels and faults on the northwest flank of

  3. Influence of flanking sequences on presentation efficiency of a CD8+ cytotoxic T-cell epitope delivered by parvovirus-like particles.

    PubMed

    Rueda, P; Morón, G; Sarraseca, J; Leclerc, C; Casal, J I

    2004-03-01

    We have previously developed an antigen-delivery system based on hybrid recombinant porcine parvovirus-like particles (PPV-VLPs) formed by the self-assembly of the VP2 protein of PPV carrying a foreign epitope at its N terminus. In this study, different constructs were made containing a CD8(+) T-cell epitope of chicken ovalbumin (OVA) to analyse the influence of the sequence inserted into VP2 on the correct processing of VLPs by antigen-presenting cells. We analysed the presentation of the OVA epitope inserted without flanking sequences or with either different natural flanking sequences or with the natural flanking sequences of a CD8(+) T-cell epitope from the lymphocytic choriomeningitis virus nucleoprotein, and as a dimer with or without linker sequences. All constructs were studied in terms of level of expression, assembly of VLPs and ability to deliver the inserted epitope into the MHC I pathway. The presentation of the OVA epitope was considerably improved by insertion of short natural flanking sequences, which indicated the relevance of the flanking sequences on the processing of PPV-VLPs. Only PPV-VLPs carrying two copies of the OVA epitope linked by two glycines were able to be properly processed, suggesting that the introduction of flexible residues between the two consecutive OVA epitopes may be necessary for the correct presentation of these dimers by PPV-VLPs. These results provide information to improve the insertion of epitopes into PPV-VLPs to facilitate their processing and presentation by MHC class I molecules. PMID:14993639

  4. New insights into the last deglaciation of the south-eastern flank of the Scandinavian Ice Sheet

    NASA Astrophysics Data System (ADS)

    Bitinas, Albertas

    2012-06-01

    The existing glaciodynamic paradigm used to explain the dynamics, morphogenesis, and deglaciation of the last Scandinavian Ice Sheet (SIS) does not satisfactorily reflect all the nuances of ice sheet dynamics, formation of particular forms of glacial relief, and details of deglaciation. Significant problems are to be found in the explanations proposed for the processes of deglaciation. Therefore a new theory for the deglaciation of the last SIS, based on new geochronological, geological, and geomorphological data has been developed and is presented here. It is suggested that along the south-eastern perimeter of the SIS, with the exception of the Salpausselkä moraine ridges, there is no evidence anywhere for re-advances of the SIS during deglaciation. Apart from the Salpausselkä moraine ridges the evidence for so-called 'stadial' or 'phasial' recessional events is interpreted as the result of SIS surges that occurred at different times and positions along the ice sheet margin. This new theory also proposes that deglaciation of the south-eastern flank of the SIS was dominated by surface thinning rather than marginal retreat. Characteristic landforms such as kame terraces located on the distal slopes of recessional marginal ridges and plateau-like glaciolacustrine kames, were developed during deglaciation probably due to the interaction of active ice lobes (surges) and masses of dead ice that persisting beyond the ice margin.

  5. Diversity and Metabolic Potentials of Subsurface Crustal Microorganisms from the Western Flank of the Mid-Atlantic Ridge

    PubMed Central

    Zhang, Xinxu; Feng, Xiaoyuan; Wang, Fengping

    2016-01-01

    Deep-sea oceanic crust constitutes the largest region of the earth’s surface. Accumulating evidence suggests that unique microbial communities are supported by iron cycling processes, particularly in the young (<10 million-year old), cool (<25°C) subsurface oceanic crust. To test this hypothesis, we investigated the microbial abundance, diversity, and metabolic potentials in the sediment-buried crust from “North Pond” on western flank of the Mid-Atlantic Ridge. Three lithologic units along basement Hole U1383C were found, which typically hosted ∼104 cells cm-3 of basaltic rock, with higher cell densities occurring between 115 and 145 m below seafloor. Similar bacterial community structures, which are dominated by Gammaproteobacterial and Sphingobacterial species closely related to iron oxidizers, were detected regardless of variations in sampling depth. The metabolic potentials of the crust microbiota were assayed by metagenomic analysis of two basalt enrichments which showed similar bacterial structure with the original sample. Genes coding for energy metabolism involved in hydrocarbon degradation, dissimilatory nitrate reduction to ammonium, denitrification and hydrogen oxidation were identified. Compared with other marine environments, the metagenomes from the basalt-hosted environments were enriched in pathways for Fe3+ uptake, siderophore synthesis and uptake, and Fe transport, suggesting that iron metabolism is an important energy production and conservation mechanism in this system. Overall, we provide evidence that the North Pond crustal biosphere is dominated by unique bacterial groups with the potential for iron-related biogeochemical cycles. PMID:27047476

  6. The Complex Genetic Context of blaPER-1 Flanked by Miniature Inverted-Repeat Transposable Elements in Acinetobacter johnsonii

    PubMed Central

    Zong, Zhiyong

    2014-01-01

    On a large plasmid of Acinetobacter johnsonii strain XBB1 from hospital sewage, blaPER-1 and ISCR1 were found in a complex Tn402-like integron carrying an arr3-aacA4 cassette array. The integron was truncated by the same 439-bp miniature inverted-repeat transposable element (MITE) at both ends. blaPER-1 and its complex surroundings might have been mobilized by the MITEst into an orf of unknown function, evidenced by the presence of the characteristic 5-bp direct target repeats. The same 439-bp MITEs have also been found flanking class 1 integrons carrying metallo-β-lactamases genes blaIMP-1, blaIMP-5 and blaVIM-2 before but without ISCR1. Although the cassette arrays are different, integrons have always been truncated by the 439-bp MITEs at the exact same locations. The results suggested that MITEs might be able to mobilize class 1 integrons via transposition or homologous recombination and therefore represent a possible common mechanism for mobilizing antimicrobial resistance determinants. PMID:24587208

  7. Flank instability of Stromboli volcano (Aeolian Islands, Southern Italy): Integration of GB-InSAR and geomorphological observations

    NASA Astrophysics Data System (ADS)

    Intrieri, Emanuele; Di Traglia, Federico; Del Ventisette, Chiara; Gigli, Giovanni; Mugnai, Francesco; Luzi, Guido; Casagli, Nicola

    2013-11-01

    Stromboli is characterized by frequent explosions of variable energy and periodically interrupted by more energetic blasts emitting large volumes of material. The pressurization of a volatile-poor, high-porphyritic magma column that is gas-recharged by the deep-seated, volatile-rich, low-porphyritic magma precedes such events and produces deformations on the NW flank of the volcano, Sciara del Fuoco. By integrating geomorphological observations with long-term displacements from ground-based interferometric radar since December 2007, we identified two landslides whose movements are strongly related with volcanic activity. Movement patterns obtained through a novel long-term analysis of GB-InSAR data permitted us to hypothesize the type of movement and depth for both landslides. Furthermore their position allowed us to affirm that the effusive vent formed in 2007 at 400 m a.s.l., was the result of the deflection of a feeder dike caused by landslide fractures, thus showing the important role of geomorphological discontinuities in volcanic environments.

  8. Landscape of a Glaciated Rift Flank: Structure of the Transantarctic Mountains From the Royal Society Range to the Churchill Mountains

    NASA Astrophysics Data System (ADS)

    Demyanick, E.; Wilson, T. J.

    2006-12-01

    Multiphase tectonic activity has shaped the regional landscape of the Transantarctic Mountains in Paleozoic, Jurassic, and Cenozoic times. The Antarctic ice sheets have covered the continent for the last 34 m.y. and coeval glacial activity and tectonism have affected mountain landscape evolution. Large-scale linear morphologic features within the mountains are controlled by bedrock structure. Satellite imagery and digital elevation models (DEMs) have been used in this study to map regional, linear morphologic trends along the mountain chain between the Royal Society Range and the Churchill Mountains. ASTER imagery was mosaicked and processed to enhance linear features and lineament analysis was employed to quantify major trends in the mountains. These trends were then compared to geologic maps and other structural and geomorphic data for the area. A low-resolution DEM derived from topographic map contours and new, higher- resolution DEMs created from ASTER imagery were used to create contour, shaded relief, slope steepness, and slope aspect maps. Geomorphology was assessed using these maps and related to mapped lineaments. Linear features that parallel known rift-related faults, or form typical rift-fault patterns, were used to develop a structural model for the architecture of this sector of the Transantarctic Mountains rift flank.

  9. The Kuqa late Cenozoic fold-thrust belt on the southern flank of the Tian Shan Mountains

    NASA Astrophysics Data System (ADS)

    Li, Yue-Jun; Wen, Lei; Zhang, Hong-An; Huang, Tai-Zhu; Li, Hui-Li; Shi, Yuan-Yuan; Meng, Qing-Long; Peng, Geng-Xin; Huang, Shao-Ying; Zhang, Qiang

    2015-10-01

    The Kuqa fold-thrust belt (KFTB), a late Cenozoic fold-thrust belt on the southern flank of the Tian Shan Mountains, consists of several deformation zones trending nearly W-E. The main décollement fault of the KFTB gradually rises southwards. There are three regional main décollement faults in the Triassic dark mudstone, Paleogene gypsum salt (Kumugeliemu Formation), and Neogene gypsum salt (Jidike Formation), respectively, and possibly a fourth in the Jurassic coalbed. Laterally, thin-skinned structures are developed in the main segments of the KFTB, whereas thick-skinned structures are in the root zone. Vertically, the structural deformation above the Cenozoic gypsum-salt layers (Paleogene gypsum salt in the middle segment of the KFTB and Neogene gypsum salt in the eastern segment) is characterized by décollement folding, whereas that below is characterized by thrusting. The KFTB was resulted from the late Cenozoic intra-continental orogeny in the Tian Shan area under the far-field effect of the India-Asia collision. The deformation of KFTB began (folding and thrusting) ca. 23 Ma, when the far-field effect of the India-Asia collision reached the Tian Shan area. The deformation of KFTB accelerated ca. 10, 5-2, and 1-0 Ma. In general, the evolution of the KFTB is forward propagating, and the hinter parts of the KFTB continue to deform, while its front propagates southwards.

  10. The splicing regulatory element, UGCAUG, is phylogenetically and spatially conserved in introns that flank tissue-specific alternative exons

    PubMed Central

    Minovitsky, Simon; Gee, Sherry L.; Schokrpur, Shiruyeh; Dubchak, Inna; Conboy, John G.

    2005-01-01

    Previous studies have identified UGCAUG as an intron splicing enhancer that is frequently located adjacent to tissue-specific alternative exons in the human genome. Here, we show that UGCAUG is phylogenetically and spatially conserved in introns that flank brain-enriched alternative exons from fish to man. Analysis of sequence from the mouse, rat, dog, chicken and pufferfish genomes revealed a strongly statistically significant association of UGCAUG with the proximal intron region downstream of brain-enriched alternative exons. The number, position and sequence context of intronic UGCAUG elements were highly conserved among mammals and in chicken, but more divergent in fish. Control datasets, including constitutive exons and non-tissue-specific alternative exons, exhibited a much lower incidence of closely linked UGCAUG elements. We propose that the high sequence specificity of the UGCAUG element, and its unique association with tissue-specific alternative exons, mark it as a critical component of splicing switch mechanism(s) designed to activate a limited repertoire of splicing events in cell type-specific patterns. We further speculate that highly conserved UGCAUG-binding protein(s) related to the recently described Fox-1 splicing factor play a critical role in mediating this specificity. PMID:15691898

  11. Characterisation of two deletions involving NPC1 and flanking genes in Niemann-Pick type C disease patients.

    PubMed

    Rodríguez-Pascau, Laura; Toma, Claudio; Macías-Vidal, Judit; Cozar, Mónica; Cormand, Bru; Lykopoulou, Lilia; Coll, Maria Josep; Grinberg, Daniel; Vilageliu, Lluïsa

    2012-12-01

    Niemann-Pick type C (NPC) disease is an autosomal recessive lysosomal disorder characterised by the accumulation of a complex pattern of lipids in the lysosomal-late endosomal system. More than 300 disease-causing mutations have been identified so far in the NPC1 and NPC2 genes, including indel, missense, nonsense and splicing mutations. Only one genomic deletion, of more than 23 kb, has been previously reported. We describe two larger structural variants, encompassing NPC1 and flanking genes, as a cause of the disease. QMPSF, SNP inheritance and CytoScan® HD Array were used to confirm and further characterise the presence of hemizygous deletions in two patients. One of the patients (NPC-57) bore a previously described missense mutation (p.T1066N) and an inherited deletion that included NPC1, C18orf8 and part of ANKRD29 gene. The second patient (NPC-G1) had a 1-bp deletion (c.852delT; p.F284Lfs*26) and a deletion encompassing the promoter region and exons 1-10 of NPC1 and the adjacent ANKRD29 and LAMA3. This study characterised two novel chromosomal microdeletions at 18q11-q12 that cause NPC disease and provide insight into missing NPC1 mutant alleles. PMID:23142039

  12. Definition of a lipopolysaccharide-responsive element in the 5'-flanking regions of MuRantes and crg-2.

    PubMed Central

    Shin, H S; Drysdale, B E; Shin, M L; Noble, P W; Fisher, S N; Paznekas, W A

    1994-01-01

    Macrophages are stimulated by lipopolysaccharide (LPS) of gram-negative organisms. The changes in LPS-stimulated macrophages include transcriptional activation of multiple immediate-early genes, which may contribute to the natural immunity to microorganisms. We have defined by deletion and mutational analysis LPS-responsive elements (LREs) in two chemokine genes, MuRantes and crg-2, which are activated in an immediate-early manner. LRE consists of two motifs, TCAYR, which is an AP-1 half site with two flanking bases, and (A/T) (G/C)NTTYC(A/T)NTTY, which resembles in part the interferon-stimulated responsive element (ISRE). The orientation of these two motifs relative to each other in MuRantes differed from that in crg-2. These two motifs are separated by 10 and 6 nonconsensus nucleotides in the MuRantes and crg-2 LREs, respectively. Stimulation of macrophage-like RAW 264.7 cells with alpha/beta interferon did not activate MuRantes, indicating that the ISRE-like motif in MuRantes does not have ISRE activity. Upon stimulation of RAW 264.7 cells with LPS, proteins capable of binding to LRE accumulate in the nuclei as measured by electrophoretic mobility shift assay. These LRE-binding proteins include c-Jun and CREB. Images PMID:7513046

  13. Replication fork progression is paused in two large chromosomal zones flanking the DNA replication origin in Escherichia coli.

    PubMed

    Akiyama, Masahiro Tatsumi; Oshima, Taku; Chumsakul, Onuma; Ishikawa, Shu; Maki, Hisaji

    2016-08-01

    Although the speed of nascent DNA synthesis at individual replication forks is relatively uniform in bacterial cells, the dynamics of replication fork progression on the chromosome are hampered by a variety of natural impediments. Genome replication dynamics can be directly measured from an exponentially growing cell population by sequencing newly synthesized DNA strands that were specifically pulse-labeled with the thymidine analogue 5-bromo-2'-deoxyuridine (BrdU). However, a short pulse labeling with BrdU is impracticable for bacteria because of poor incorporation of BrdU into the cells, and thus, the genomewide dynamics of bacterial DNA replication remain undetermined. Using a new thymidine-requiring Escherichia coli strain, eCOMB, and high-throughput sequencing, we succeeded in determining the genomewide replication profile in bacterial cells. We also found that fork progression is paused in two ~200-kb chromosomal zones that flank the replication origin in the growing cells. This origin-proximal obstruction to fork progression was overcome by an increased thymidine concentration in the culture medium and enhanced by inhibition of transcription. These indicate that DNA replication near the origin is sensitive to the impediments to fork progression, namely a scarcity of the DNA precursor deoxythymidine triphosphate and probable conflicts between replication and transcription machineries. PMID:27353572

  14. Tightly linked flanking microsatellite markers for the Usher syndrome type I locus on the short arm of chromosome 11

    SciTech Connect

    Keats, B.J.B.; Nouri, N.; Pelias, M.Z.; Deininger, P.L. ); Litt, M. )

    1994-04-01

    Usher syndrome type I is an autosomal recessive disease characterized by profound congenital hearing impairment and vestibular dysfunction followed by the onset of progressive pigmentary retinopathy in childhood or early adolescence. A locus (USH1C) for one form of this disease was previously assigned to the short arm of chromosome 11 through linkage studies in the Acadian population of southwestern Louisiana. Linkage analyses of a set of microsatellite markers in 27 Acadian families provide evidence that USH1C lies between D11S861 and D11S928. Three markers (D11S419, D11S921, and D11S899) that lie between the flanking markers show no recombination with USH1C, and all 54 chromosomes with the abnormal allele at the disease locus have identical alleles for D11S419 and D11S921. This haplotype was found on only 10 of 50 chromosomes with the normal allele at the disease locus, suggesting a strong founder effect. Of the 54 chromosomes with the abnormal allele, 12 had a divergent allele at D11S899. These results suggest that USH1C is in the 2-3-cM interval between D11S861 and D11S899. 16 refs., 2 figs., 3 tabs.

  15. Solution structure of gamma-bungarotoxin: the functional significance of amino acid residues flanking the RGD motif in integrin binding.

    PubMed

    Shiu, Jia-Hau; Chen, Chiu-Yueh; Chang, Long-Sen; Chen, Yi-Chun; Chen, Yen-Chin; Lo, Yu-Hui; Liu, Yu-Chen; Chuang, Woei-Jer

    2004-12-01

    Gamma-bungarotoxin, a snake venom protein isolated from Bungarus multicinctus, contains 68 amino acids, including 10 cysteine residues and a TAVRGDGP sequence at positions 30-37. The solution structure of gamma-bungarotoxin has been determined by nuclear magnetic resonance (NMR) spectroscopy. The structure is similar to that of the short-chain neurotoxins that contain three loops extending from a disulfide-bridged core. The tripeptide Arg-Gly-Asp (RGD) sequence is located at the apex of the flexible loop and is similar to that of other RGD-containing proteins. However, gamma-bungarotoxin only inhibits platelet aggregations with an IC50 of 34 microM. To understand its weak activity in inhibiting platelet aggregation, we mutated the RGD loop sequences of rhodostomin, a potent platelet aggregation inhibitor, from RIPRGDMP to TAVRGDGP, resulting in a 196-fold decrease in activity. In addition, the average Calpha-to-Calpha distance between R33 and G36 of gamma-bungarotoxin is 6.02 A, i.e., shorter than that of other RGD-containing proteins that range from 6.55 to 7.46 A. These results suggested that the amino acid residues flanking the RGD motif might control the width of the RGD loop. This structural difference may be responsible for its decrease in platelet aggregation inhibition compared with other RGD-containing proteins. PMID:15390258

  16. A novel PCR technique using Alu-specific primers to identify unknown flanking sequences from the human genome

    SciTech Connect

    Minami, M.; Poussin, K.; Brechot, C.; Paterlini, P.

    1995-09-20

    The rapid and reproducible identification of new cellular DNA sequences is difficult to achieve with the currently available procedures. Here we describe a novel approach based on the polymerase chain reaction (PCR) using a primer specific to the known sequence and another directed to a human Alu repeat. To avoid undesirable amplifications between Alu sequences, primers are constructed with dUTPs and destroyed by uracil DNA glycosylase treatment after 10 initial cycles of amplification. Only desirable fragments are then further amplified with specific primers to the known region and to a tag sequence introduced in the Alu-specific primer. Using this protocol, we have successfully indentified cellular sequences flanking integrated hepatitis B virus DNA from the human genome of three hepatoma tissues. The method enables a direct specific amplification without any ligation or nonspecific annealing steps as required by previous PCR-based protocols. This rapid and straightforward approach will be a powerful tool for the study of viral integration sites, but is also widely applicable to other studies of the human genome. 39 refs., 4 figs.

  17. Carbon and Nutrient Dynamics in Cool Ridge-Flank Hydrothermal Springs: The Dorado Outcrop of the Eastern Pacific.

    NASA Astrophysics Data System (ADS)

    McManus, J.; Wheat, C. G.; Orcutt, B.; Fisher, A. T.; Hulme, S.; Burdige, D.

    2015-12-01

    The Dorado outcrop is a basaltic edifice that protrudes through the marine sediments that cover the seafloor along the eastern flank of the East Pacific Rise. This outcrop is an exit conduit for cool, chemically altered crustal fluids. We sampled exiting fluids using a variety of techniques including autonomous, time-series samplers (OsmoSamplers) and discrete sampling using the DSV Alvin. We also collected and analyzed pore fluids from a series of short sediment cores in the vicinity of hydrothermal springs. Samples for the major nutrients show that silicic acid is significantly enriched within the venting fluids relative to the concentration in bottom seawater, whereas dissolved phosphate is depleted within these fluids. Concentrations of dissolved inorganic carbon appear to be slightly elevated in hydrothermal fluids relative to bottom seawater. Pore fluids are highly variable in their concentrations for the major nutrients, perhaps because of variable exchange between these fluids and the underlying crustal fluids. Our results indicate that the fluids within this crustal aquifer system undergo alteration during their rapid transit within the volcanic crust. The chemical composition of these fluids appears to be influenced by exchange with the overlying sediment pore fluids as well as reactions internal to the volcanic crustal reservoir.

  18. Cloning and Characterization of 5′ Flanking Regulatory Sequences of AhLEC1B Gene from Arachis Hypogaea L.

    PubMed Central

    Tang, Guiying; Xu, Pingli; Liu, Wei; Liu, Zhanji; Shan, Lei

    2015-01-01

    LEAFY COTYLEDON1 (LEC1) is a B subunit of Nuclear Factor Y (NF-YB) transcription factor that mainly accumulates during embryo development. We cloned the 5′ flanking regulatory sequence of AhLEC1B gene, a homolog of Arabidopsis LEC1, and analyzed its regulatory elements using online software. To identify the crucial regulatory region, we generated a series of GUS expression frameworks driven by different length promoters with 5′ terminal and/or 3′ terminal deletion. We further characterized the GUS expression patterns in the transgenic Arabidopsis lines. Our results show that both the 65bp proximal promoter region and the 52bp 5′ UTR of AhLEC1B contain the key motifs required for the essential promoting activity. Moreover, AhLEC1B is preferentially expressed in the embryo and is co-regulated by binding of its upstream genes with both positive and negative corresponding cis-regulatory elements. PMID:26426444

  19. Characterization of the 5' flanking region of lipase gene from Penicillium expansum and its application in molecular breeding.

    PubMed

    Zhang, Tian; Peng, Ying; Yu, Qingsheng; Wang, Jieliang; Tang, Kexuan

    2014-01-01

    A major challenge for further promotion of lipase productivity in Penicillium expansum PE-12 is to find a suitable promoter that can function efficiently in this industrial strain. In this study, the 5' flanking region of P. expansum lipase (Ppel) containing a putative novel promoter sequence was characterized by fusing to β-glucuronidase (GUS) and subsequently introducing into P. expansum. As a result, all the transformants showed blue color quickly after incubation in GUS detection buffer, suggesting a strong promoter activity of this fragment. Glucose repression was identified for the promoter, whereas olive oil acted as a positive regulator. Facilitated by this novel promoter, P. expansum PE-12 was genetically modified, with an improved lipase yield, via a recombinant plasmid with P. expansum lipase gene (PEL) under the control of Ppel promoter and TtrpC terminator. The highest lipase yield among the modified strains could attain 2,100 U/mL, which is more than twofold of the previous industrial strain (900 U/mL). The engineered strain through molecular breeding method as well as this new promoter has great value in lipase industry. PMID:24502561

  20. aPKC Inhibition by Par3 CR3 Flanking Regions Controls Substrate Access and Underpins Apical-Junctional Polarization.

    PubMed

    Soriano, Erika V; Ivanova, Marina E; Fletcher, Georgina; Riou, Philippe; Knowles, Philip P; Barnouin, Karin; Purkiss, Andrew; Kostelecky, Brenda; Saiu, Peter; Linch, Mark; Elbediwy, Ahmed; Kjær, Svend; O'Reilly, Nicola; Snijders, Ambrosius P; Parker, Peter J; Thompson, Barry J; McDonald, Neil Q

    2016-08-22

    Atypical protein kinase C (aPKC) is a key apical-basal polarity determinant and Par complex component. It is recruited by Par3/Baz (Bazooka in Drosophila) into epithelial apical domains through high-affinity interaction. Paradoxically, aPKC also phosphorylates Par3/Baz, provoking its relocalization to adherens junctions (AJs). We show that Par3 conserved region 3 (CR3) forms a tight inhibitory complex with a primed aPKC kinase domain, blocking substrate access. A CR3 motif flanking its PKC consensus site disrupts the aPKC kinase N lobe, separating P-loop/αB/αC contacts. A second CR3 motif provides a high-affinity anchor. Mutation of either motif switches CR3 to an efficient in vitro substrate by exposing its phospho-acceptor site. In vivo, mutation of either CR3 motif alters Par3/Baz localization from apical to AJs. Our results reveal how Par3/Baz CR3 can antagonize aPKC in stable apical Par complexes and suggests that modulation of CR3 inhibitory arms or opposing aPKC pockets would perturb the interaction, promoting Par3/Baz phosphorylation. PMID:27554858

  1. Deep, wide-field, global VLBI observations of the Hubble deep field north (HDF-N) and flanking fields (HFF)

    NASA Astrophysics Data System (ADS)

    Chi, S.; Barthel, P. D.; Garrett, M. A.

    2013-02-01

    Context. Dust is commonly present in weakly radio emitting star-forming galaxies and this dust may obscure the signatures of accreting black holes in these objects. Aims: We aim to uncover weak active galactic nuclei, AGN, in the faint radio source population by means of deep high-resolution radio observations. Methods: VLBI observations with a world-wide array at unparallelled sensitivity are carried out to assess the nature of the faint radio source population in the Hubble deep field north and its flanking fields. Results: Images of twelve compact, AGN-driven radio sources are presented. These represent roughly one quarter of the detectable faint radio source sample. Most, but not all of these low power AGN have X-ray detections. Conclusions: The majority of the faint radio source population must be star-forming galaxies. Faint AGN occur in a variety of (distant) host galaxies, and these are often accompanied by a dust-obscured starburst. Deep, high-resolution VLBI is a unique, powerful technique to assess the occurrence of faint AGN.

  2. A model-dye comparison experiment in the tidal mixing front zone on the southern flank of Georges Bank

    NASA Astrophysics Data System (ADS)

    Chen, Changsheng; Xu, Qichun; Houghton, Robert; Beardsley, Robert C.

    2008-02-01

    A process-oriented model-dye comparison experiment was conducted to examine the ability of a numerical ocean model to simulate the observed movement of dye across the tidal mixing front on the southern flank of Georges Bank during 22-26 May 1999. The experiment was made using the unstructured-grid Finite-Volume Coastal Ocean Model (FVCOM) with varying horizontal resolution. The results indicate that the observed cross-isobath movement of the dye patch was primarily controlled by meso-scale temporal and spatial variability of the water temperature and salinity fields. Onset of vertical stratification tended to slow down an upward stretching of the dye column and trapped the dye within the bottom mixed layer. To reach a convergent numerical solution that reproduced the observed lateral turbulent dispersion of dye, the FVCOM grid required a horizontal resolution of ˜500 m in the dye study region. Within the tidal mixing front of Georges Bank, the movement of the center of the dye patch was mainly driven by the ensemble velocity integrated over the dye volume, with a first-order contribution from vertical shear of the dye's horizontal velocity.

  3. The Kuqa late Cenozoic fold-thrust belt on the southern flank of the Tian Shan Mountains

    NASA Astrophysics Data System (ADS)

    Li, Yue-Jun; Wen, Lei; Zhang, Hong-An; Huang, Tai-Zhu; Li, Hui-Li; Shi, Yuan-Yuan; Meng, Qing-Long; Peng, Geng-Xin; Huang, Shao-Ying; Zhang, Qiang

    2016-07-01

    The Kuqa fold-thrust belt (KFTB), a late Cenozoic fold-thrust belt on the southern flank of the Tian Shan Mountains, consists of several deformation zones trending nearly W-E. The main décollement fault of the KFTB gradually rises southwards. There are three regional main décollement faults in the Triassic dark mudstone, Paleogene gypsum salt (Kumugeliemu Formation), and Neogene gypsum salt (Jidike Formation), respectively, and possibly a fourth in the Jurassic coalbed. Laterally, thin-skinned structures are developed in the main segments of the KFTB, whereas thick-skinned structures are in the root zone. Vertically, the structural deformation above the Cenozoic gypsum-salt layers (Paleogene gypsum salt in the middle segment of the KFTB and Neogene gypsum salt in the eastern segment) is characterized by décollement folding, whereas that below is characterized by thrusting. The KFTB was resulted from the late Cenozoic intra-continental orogeny in the Tian Shan area under the far-field effect of the India-Asia collision. The deformation of KFTB began (folding and thrusting) ca. 23 Ma, when the far-field effect of the India-Asia collision reached the Tian Shan area. The deformation of KFTB accelerated ca. 10, 5-2, and 1-0 Ma. In general, the evolution of the KFTB is forward propagating, and the hinter parts of the KFTB continue to deform, while its front propagates southwards.

  4. Diversity and Metabolic Potentials of Subsurface Crustal Microorganisms from the Western Flank of the Mid-Atlantic Ridge.

    PubMed

    Zhang, Xinxu; Feng, Xiaoyuan; Wang, Fengping

    2016-01-01

    Deep-sea oceanic crust constitutes the largest region of the earth's surface. Accumulating evidence suggests that unique microbial communities are supported by iron cycling processes, particularly in the young (<10 million-year old), cool (<25°C) subsurface oceanic crust. To test this hypothesis, we investigated the microbial abundance, diversity, and metabolic potentials in the sediment-buried crust from "North Pond" on western flank of the Mid-Atlantic Ridge. Three lithologic units along basement Hole U1383C were found, which typically hosted ∼10(4) cells cm(-3) of basaltic rock, with higher cell densities occurring between 115 and 145 m below seafloor. Similar bacterial community structures, which are dominated by Gammaproteobacterial and Sphingobacterial species closely related to iron oxidizers, were detected regardless of variations in sampling depth. The metabolic potentials of the crust microbiota were assayed by metagenomic analysis of two basalt enrichments which showed similar bacterial structure with the original sample. Genes coding for energy metabolism involved in hydrocarbon degradation, dissimilatory nitrate reduction to ammonium, denitrification and hydrogen oxidation were identified. Compared with other marine environments, the metagenomes from the basalt-hosted environments were enriched in pathways for Fe(3+) uptake, siderophore synthesis and uptake, and Fe transport, suggesting that iron metabolism is an important energy production and conservation mechanism in this system. Overall, we provide evidence that the North Pond crustal biosphere is dominated by unique bacterial groups with the potential for iron-related biogeochemical cycles. PMID:27047476

  5. Synthesis and identification of the monocation Tc(CPI) sub 6 sup + in Tc(CNC(CH sub 3 ) sub 2 COOCH sub 3 ) sub 6 Cl and its hydrolysis products. [Tc(CNC(CH sub 3 ) sub 2 COOCH sub 3 ) sub 6 Cl and monocation Tc(CPI) sub 6 sup +

    SciTech Connect

    Kronauge, J.F.; Davison, A.; Roseberry, A.M.; Costello, C.E.; Maleknia, S. ); Jones, A.G. )

    1991-10-30

    The complex Tc(CNC(CH{sub 3}){sub 2}COOCH{sub 3}){sub 6}Cl (cation designated as Tc(CPI){sub 6}{sup +}) is one of a series of isonitrile-coordinated technetium complexes being investigated as a prototype radiopharmaceutical to evaluate myocardial perfusion. It has been prepared from the pertechnetate ion by aqueous Na{sub 2}S{sub 2}O{sub 4} reduction in the presence of the functionalized isocyanide ligand. The octahedral compound with its relatively reactive ester substituents is stable under aqueous aerobic conditions within the pH range 5-7. At high pH, however, the ester moieties undergo random, base-catalyzed hydrolysis while the six ligands remain coordinated in a fixed geometry to the central metal. The nine predicted carboxylic acid containing species were separated and identified by RP-HPLC, FAB-MS, IR, and {sup 99}Tc NMR methods. Specific k' values obtained from the RP-HPLC of these characterized compounds were used to identify technetium containing metabolites of the radiopharmaceutical. Varying rates of in vitro enzymatic hydrolysis at the terminal ester moieties of the coordinated ligands were shown to occur when this compound was incubated with blood serum from different animal species.

  6. Differential flank growth

    NASA Astrophysics Data System (ADS)

    Zieschang, H. E.; Sievers, A.

    1994-08-01

    With the mathematical basis for the precise analysis of developmental processes in plants, the patterns of growth in phototropic and gravitropic responses have become better understood. A detailed temporal and spatial quantification of a growth process is an important tool for evaluating hypotheses about the underlying physiological mechanisms. Studies of growth rates and curvature show that the original Cholodny-Went hypothesis cannot explain the complex growth patterns during tropic responses of shoots and roots. In addition, regulating factors other than the lateral redistribution of hormones must be taken into account. Electrophysiological studies on roots led to a modification of the Cholodny-Went hypothesis in that redistributions of bioelectrical activities are observed.

  7. The Rock Engineering System (RES) applied to landslide susceptibility zonation of the northeastern flank of Etna: methodological approach and results

    NASA Astrophysics Data System (ADS)

    Apuani, Tiziana; Corazzato, Claudia

    2015-04-01

    Ground deformations in the northeastern flank of Etna are well known. Despite only a few landslide events have been documented, these have significantly involved and damaged lifelines and buildings. These events are mainly related to the activity of the volcano-tectonic structures and associated seismicity, as in the case of the 2002 reactivation of the Presa landslide during an increased activity of the Pernicana fault system. In order to highlight the areal distribution of potentially unstable slopes based on a detailed, site-specific study of the factors responsible for landslide, and to ultimately contribute to risk management, a landslide susceptibility analysis of the northeastern flank of Etna in the Pernicana area was carried out, and a susceptibility map at 1:10.000 scale was produced, extending over an area of 168 km2. Different methods are proposed in the literature to obtain the regional distribution of potentially unstable slopes, depending on the problem scale, the slope dynamic evolution in the geological context, and the availability of data. Among semi-quantitative approaches, the present research combines the Rock Engineering System (RES) methodology with parameter zonation mapping in a GIS environment. The RES method represents a structured approach to manage a high number of interacting factors involved in the instability problem. A numerically coded, site-specific interaction matrix (IM) analyzes the cause-effect relationship in these factors, and calculates the degree of interactivity of each parameter, normalized by the overall interactivity of the system (weight factor). In the specific Etna case, the considered parameters are: slope attitude, lithotechnical properties (lithology, structural complexity, soil and rock mass quality), land use, tectonic structures, seismic activity (horizontal acceleration) and hydrogeological conditions (groundwater and drainage). Thematic maps are prepared at 1:10.000 scale for each of these parameters, and

  8. A Receptor-Based Explanation for Tsetse Fly Catch Distribution between Coloured Cloth Panels and Flanking Nets

    PubMed Central

    Santer, Roger D.

    2015-01-01

    Tsetse flies transmit trypanosomes that cause nagana in cattle, and sleeping sickness in humans. Therefore, optimising visual baits to control tsetse is an important priority. Tsetse are intercepted at visual baits due to their initial attraction to the bait, and their subsequent contact with it due to landing or accidental collision. Attraction is proposed to be driven in part by a chromatic mechanism to which a UV-blue photoreceptor contributes positively, and a UV and a green photoreceptor contribute negatively. Landing responses are elicited by stimuli with low luminance, but many studies also find apparently strong landing responses when stimuli have high UV reflectivity, which would imply that UV wavelengths contribute negatively to attraction at a distance, but positively to landing responses at close range. The strength of landing responses is often judged using the number of tsetse sampled at a cloth panel expressed as a proportion of the combined catch of the cloth panel and a flanking net that samples circling flies. I modelled these data from two previously published field studies, using calculated fly photoreceptor excitations as predictors. I found that the proportion of tsetse caught on the cloth panel increased with an index representing the chromatic mechanism driving attraction, as would be expected if the same mechanism underlay both long- and close-range attraction. However, the proportion of tsetse caught on the cloth panel also increased with excitation of the UV-sensitive R7p photoreceptor, in an apparently separate but interacting behavioural mechanism. This R7p-driven effect resembles the fly open-space response which is believed to underlie their dispersal towards areas of open sky. As such, the proportion of tsetse that contact a cloth panel likely reflects a combination of deliberate landings by potentially host-seeking tsetse, and accidental collisions by those seeking to disperse, with a separate visual mechanism underlying each

  9. Three indel variants in chicken LPIN1 exon 6/flanking region are associated with performance and carcass traits.

    PubMed

    Wang, R; Wang, T; Lu, W; Zhang, W; Chen, W; Kang, X; Huang, Y

    2015-01-01

    LPIN1 is a Mg(2+)-dependent phosphatidic acid phosphatase. Variation in chicken LPIN1 exon 6 and its flanking regions were identified and three indel variants in 6 breeds and their associations with performance traits were studied. Seven variants were detected from 6 breeds, which contained a synonymous tri-allelic variant (c.924A/T/C) and three indels. The exon 6 variants detected from chicken breeds were conserved among bird species. The indel variation frequency presented clear differences among breeds. Two coding indels (c.1014-1018del3 and c.1125-1138del12) were multiples of three nucleotides and maintained the open reading frames of LPIN1 proteins. However, they were predicted to result in the clear change of the RNA secondary structure of chicken LPIN1 exon 6 and LPIN1 protein conformation. The association analysis showed that c.871-15-22del6 variation had a significant effect on body weight at hatch (BW0) and 2 weeks (BW2); c. 1014-1018del3 variation had a significant effect on BW4, BW6, caecum length and gizzard weight (GW) traits; c.1125-1138del12 variation had a significant effect on BW12, shank length at 4 weeks (SL4), carcass weight, lactate dehydrogenase traits (LDH), glucose (GLU) and albumin (ALB) traits. The genotype combination for c.1014-1018del3 and c.1125-1138del12 also presented significant effects on SL4, SL8, GW, leg muscle weight, ALB, GLU and LDH. The study demonstrated that chicken LPIN1 has an important effect on body, carcass and organ weight, serum LDH, GLU and ALB level. PMID:26523976

  10. Germline mutations of STR-alleles include multi-step mutations as defined by sequencing of repeat and flanking regions.

    PubMed

    Dauber, Eva-Maria; Kratzer, Adelgunde; Neuhuber, Franz; Parson, Walther; Klintschar, Michael; Bär, Walter; Mayr, Wolfgang R

    2012-05-01

    Well defined estimates of mutation rates are a prerequisite for the use of short tandem repeat (STR-) loci in relationship testing. We investigated 65 isolated genetic inconsistencies, which were observed within 50,796 allelic transfers at 23 STR-loci (ACTBP2 (SE33), CD4, CSF1PO, F13A1, F13B, FES, FGA, vWA, TH01, TPOX, D2S1338, D3S1358, D5S818, D7S820, D8S1132, D8S1179, D12S391, D13S317, D16S539, D17S976, D18S51, D19S433, D21S11) in Caucasoid families residing in Austria and Switzerland. Sequencing data of repeat and flanking regions and the median of all theoretically possible mutational steps showed valuable information to characterise the mutational events with regard to parental origin, change of repeat number (mutational step size) and direction of mutation (losses and gains of repeats). Apart from predominant single-step mutations including one case with a double genetic inconsistency, two double-step and two apparent four-step mutations could be identified. More losses than gains of repeats and more mutations originating from the paternal than the maternal lineage were observed (31 losses, 22 gains, 12 losses or gains and 47 paternal, 11 maternal mutations and 7 unclear of parental origin). The mutation in the paternal germline was 3.3 times higher than in the maternal germline. The results of our study show, that apart from the vast majority of single-step mutations rare multi-step mutations can be observed. Therefore, the interpretation of mutational events should not rigidly be restricted to the shortest possible mutational step, because rare but true multi-step mutations can easily be overlooked, if haplotype analysis is not possible. PMID:21873136

  11. Chemical Speciation and Oxidation Kinetics of Iron and Sulfur in Subseafloor Basement Fluids on the Juan de Fuca Ridge Flanks

    NASA Astrophysics Data System (ADS)

    Glazer, B. T.; Matzinger, M.; Cowen, J. P.

    2011-12-01

    Redox reactive chemical species circulate throughout the upper oceanic crust, and are involved in a variety of abiotic and microbially-mediated reactions. Through exchange with bottom seawater, fluids circulating in the upper basement have the potential to influence scales ranging from global-scale biogeochemical cycling to micro-scale microbe-mineral interactions. Understanding fundamental chemical speciation, distribution, bioavailability, and rates of transformations for key chemical redox species is crucial to understanding processes in the subsurface. In-situ electrochemical analyses were conducted in real-time at CORK (Circulation Obviation Retrofit Kit) observatories affixed to Integrated Ocean Drilling Program (IODP) boreholes in Cascadia Basin on the Juan de Fuca Ridge Flanks. Voltammetric electrodes were mounted into a flow cell to allow for simultaneous detection of redox species (O2, H_{2}O2, HS^{-}, S(0), Sx^{2-}, S2O_{3}2-, S_{4}O6^{2-}, Fe(II), Fe(III), FeS$_{(aq)}) concurrent to sample filtering or fluid collection. During real-time voltammetric scanning, qualitative assessment of the integrity of fluids delivered through the Fluid Delivery Lines could be made, allowing for comparisons between CORK sites and various sampling strategies. Newly installed CORKs at IODP sites 1362A and 1362B are producing the highest-integrity basement fluids collected to date, deplete in oxygen (<3uM) and enriched in iron (>1uM). Here, we report results of in situ electrochemical measurements at multiple borehole observatories, including the newly installed 1362A & 1362B sites, and present results of speciation analyses and kinetics of oxidation for iron and sulfur in discrete samples.

  12. A Receptor-Based Explanation for Tsetse Fly Catch Distribution between Coloured Cloth Panels and Flanking Nets.

    PubMed

    Santer, Roger D

    2015-01-01

    Tsetse flies transmit trypanosomes that cause nagana in cattle, and sleeping sickness in humans. Therefore, optimising visual baits to control tsetse is an important priority. Tsetse are intercepted at visual baits due to their initial attraction to the bait, and their subsequent contact with it due to landing or accidental collision. Attraction is proposed to be driven in part by a chromatic mechanism to which a UV-blue photoreceptor contributes positively, and a UV and a green photoreceptor contribute negatively. Landing responses are elicited by stimuli with low luminance, but many studies also find apparently strong landing responses when stimuli have high UV reflectivity, which would imply that UV wavelengths contribute negatively to attraction at a distance, but positively to landing responses at close range. The strength of landing responses is often judged using the number of tsetse sampled at a cloth panel expressed as a proportion of the combined catch of the cloth panel and a flanking net that samples circling flies. I modelled these data from two previously published field studies, using calculated fly photoreceptor excitations as predictors. I found that the proportion of tsetse caught on the cloth panel increased with an index representing the chromatic mechanism driving attraction, as would be expected if the same mechanism underlay both long- and close-range attraction. However, the proportion of tsetse caught on the cloth panel also increased with excitation of the UV-sensitive R7p photoreceptor, in an apparently separate but interacting behavioural mechanism. This R7p-driven effect resembles the fly open-space response which is believed to underlie their dispersal towards areas of open sky. As such, the proportion of tsetse that contact a cloth panel likely reflects a combination of deliberate landings by potentially host-seeking tsetse, and accidental collisions by those seeking to disperse, with a separate visual mechanism underlying each

  13. The Crabtree Creek pluton: A deformed Mid-Paleozoic( ) stitching pluton on the west flank of the Raleigh metamorphic belt

    SciTech Connect

    Blake, E.F. . Dept. of Earth Sciences); Stoddard, E.F. . Dept. of MEAS)

    1993-03-01

    Crystalline rocks on the west flank of the Alleghanian-aged Raleigh metamorphic belt are subdivided into four west-dipping lithotectonic terranes in the Falls Lake and north Raleigh areas. The rocks of these terranes are separated from east to west on the basis of bulk rock composition, metamorphic textural characteristics, and discrete structural discontinuities into the Raleigh terrane (RT), Crabtree terrane (CT), Falls Lake melange (FLM), and the volcanogenic Carolina slate belt (CSB). The RT and CT are separated by the dextral shear Nutbush Creek fault zone, while the Falls Lake thrust juxtaposes the CT and FLM. The structural character of the discontinuity separating the FLM and the CSB is unclear, although thrusting has been proposed. The results of geologic mapping in the Raleigh West 7.5[prime] quadrangle for the NC Geological Survey's COGEOMAP project in the Raleigh 1[degree] sheet indicate that only the CSB and CT are exposed west of I-440 between US 70 and I-40. This confirms the mapping results of Horton and others that the melange pinches out in north Raleigh just north of US 70. South of US 70, a large orthogneiss body, the Crabtree Creek composite granitic pluton, occupies the same relative position as the melange, separating mafic and intermediate metavolcanic rocks of the CSB from nonlineated and lineated interlayered schists and gneisses of the CT. The pluton is subdivided into a foliated leucocratic, medium grained muscovite granitic orthogneiss, and a foliated leucocratic to mesocratic medium to coarse grained muscovite [plus minus] biotite granitic orthogneiss containing abundant porphyroclastic disks, rods, and knobs of quartz. Because its lobes locally display intrusive contacts with metavolcanic and metasedimentary rocks of both terranes, the Crabtree Creek pluton represents an intrusion that stitched the two terranes together.

  14. Sequences flanking the pentanucleotide T-antigen binding sites in the polyomavirus core origin help determine selectivity of DNA replication.

    PubMed Central

    Li, L; Li, B L; Hock, M; Wang, E; Folk, W R

    1995-01-01

    Replication of the genomes of the polyomaviruses requires two virus-specified elements, the cis-acting origin of DNA replication, with its auxiliary DNA elements, and the trans-acting viral large tumor antigen (T antigen). Appropriate interactions between them initiate the assembly of a replication complex which, together with cellular proteins, is responsible for primer synthesis and DNA chain elongation. The organization of cis-acting elements within the origins of the polyomaviruses which replicate in mammalian cells is conserved; however, these origins are sufficiently distinct that the T antigen of one virus may function inefficiently or not at all to initiate replication at the origin of another virus. We have studied the basis for such replication selectivity between the murine polyomavirus T antigen and the primate lymphotropic polyomavirus origin. The murine polyomavirus T antigen is capable of carrying out the early steps of the assembly of an initiation complex at the lymphotropic papovavirus origin, including binding to and deformation of origin sequences in vitro. However, the T antigen inefficiently unwinds the origin, and unwinding is influenced by sequences flanking the T antigen pentanucleotide binding sites on the late side of the viral core origin. These same sequences contribute to the replication selectivity observed in vivo and in vitro, suggesting that the inefficient unwinding is the cause of the replication defect. These observations suggest a mechanism by which origins of DNA replication can evolve replication selectivity and by which the function of diverse cellular origins might be temporally activated during the S phase of the eukaryotic cell cycle. PMID:7494263

  15. Differences in Landsat TM derived lava flow thermal structures during summit and flank eruption at Mount Etna

    NASA Astrophysics Data System (ADS)

    Lombardo, V.; Buongiorno, M. F.; Pieri, D.; Merucci, L.

    2004-06-01

    The simultaneous solution of the Planck equation (the so-called "dual-band" technique) for two shortwave infrared Landsat Thematic Mapper (TM) bands allows an estimate of the fractional area of the hottest part of an active flow and the temperature of the cooler crust. Here, the dual-band method has been applied to a time series of Mount Etna eruptions. The frequency distribution of the fractional area of the hottest component reveals specific differences between summit and flank lava flows. The shape of the density function shows a trend consistent with a Gaussian distribution and suggests a relationship between the moments of the distribution and the emplacement environment. Because flow composition of Etnean lavas generally remains constant during the duration of their emplacement, it appears that the shape of any particular frequency distribution is probably related to fluid mechanical aspects of flow emplacement that affect flow velocity and flow heat loss and thus the rate of formation of the surface crust. These factors include the influence of topographical features such as changes in slope gradient, changes in volume effusion rate, and progressive downflow increases in bulk or effective viscosity. A form of the general theoretical solution for the 'dual-band' system, which illustrates the relationship between radiance in TM bands 5 and 7, corresponding to hot fractional area and crust temperature, is presented. Generally speaking, it appears that for a given flow at any point in time, larger fractional areas of exposed hot material are correlated with higher temperatures and that, while the overall shape of that distribution is common for the flows studied, its amplitude and slope reflect individual flow rheological regimes.

  16. Retrotransposition creates sloping shores: a graded influence of hypomethylated CpG islands on flanking CpG sites

    PubMed Central

    Grandi, Fiorella C.; Rosser, James M.; Newkirk, Simon J.; Yin, Jun; Jiang, Xiaoling; Xing, Zhuo; Whitmore, Leanne; Bashir, Sanum; Ivics, Zoltán; Izsvák, Zsuzsanna; Ye, Ping; Yu, Y. Eugene; An, Wenfeng

    2015-01-01

    Long interspersed elements (LINEs), through both self-mobilization and trans-mobilization of short interspersed elements and processed pseudogenes, have made an indelible impact on the structure and function of the human genome. One consequence is the creation of new CpG islands (CGIs). In fact, more than half of all CGIs in the genome are associated with repetitive DNA, three-quarters of which are derived from retrotransposons. However, little is known about the epigenetic impact of newly inserted CGIs. We utilized a transgenic LINE-1 mouse model and tracked DNA methylation dynamics of individual germline insertions during mouse development. The retrotransposed GFP marker sequence, a strong CGI, is hypomethylated in male germ cells but hypermethylated in somatic tissues, regardless of genomic location. The GFP marker is similarly methylated when delivered into the genome via the Sleeping Beauty DNA transposon, suggesting that the observed methylation pattern may be independent of the mode of insertion. Comparative analyses between insertion- and non-insertion-containing alleles further reveal a graded influence of the retrotransposed CGI on flanking CpG sites, a phenomenon that we described as “sloping shores.” Computational analyses of human and mouse methylomic data at single-base resolution confirm that sloping shores are universal for hypomethylated CGIs in sperm and somatic tissues. Additionally, the slope of a hypomethylated CGI can be affected by closely positioned CGI neighbors. Finally, by tracing sloping shore dynamics through embryonic and germ cell reprogramming, we found evidence of bookmarking, a mechanism that likely determines which CGIs will be eventually hyper- or hypomethylated. PMID:25995269

  17. Fluid and chemical fluxes along a buried-basement ridge in the eastern Juan de Fuca Ridge flank

    NASA Astrophysics Data System (ADS)

    Hulme, S.; Wheat, C. G.

    2010-12-01

    Hydrothermal fluid circulation within oceanic crust at low temperatures affects global biogeochemical cycles, with the volume of fluid circulation rivaling that of the world’s water flux to the oceans from rivers. Our work focuses on the best studied low temperature hydrothermal system on the eastern flank of the Juan de Fuca Ridge where a buried basement ridge 100 km from the active spreading axis has been sampled with a variety of mediums. We use data from deep sea drilling, gravity coring, and submersible operations from five sites along-strike of the buried ridge to better constrain the chemical and fluid fluxes along this transect. A transport (advection-diffusion) model is applied to the data, constraining the volumetric fluid flux per unit length within the oceanic crust from 0.05 and 0.2 m3 y-1 cm-1 and identifying conservative elements within this system. Using an average fluid flux, reactive fluxes are determined for non-conservative elements within basaltic crust for twenty-four chemical species. Conservative species include K, Cl, SO4, Ba, Sr, Cs, Mo, and Y. Only Ca and the rare earth elements Ce and Gd are produced by basaltic basement. The remaining chemical species Mg, Na, ammonium, Li, Rb, Mn, Fe, Co, Zn, Cd, U, La and Yb are all consumed within upper basaltic basement. Fluxes of potentially-bioavailable redox species ammonium, Fe, and Mn into the upper basaltic basement are 3 to 20 nmol y-1cm-2. Possible mechanisms of removal are suggested, placing constraints on microbial metabolic activity and biomineralization.

  18. Enzymatic generation of peptides flanked by basic amino acids to obtain MS/MS spectra with 2× sequence coverage

    PubMed Central

    Ebhardt, H Alexander; Nan, Jie; Chaulk, Steven G; Fahlman, Richard P; Aebersold, Ruedi

    2014-01-01

    RATIONALE Tandem mass (MS/MS) spectra generated by collision-induced dissociation (CID) typically lack redundant peptide sequence information in the form of e.g. b- and y-ion series due to frequent use of sequence-specific endopeptidases cleaving C- or N-terminal to Arg or Lys residues. METHODS Here we introduce arginyl-tRNA protein transferase (ATE, EC 2.3.2.8) for proteomics. ATE recognizes acidic amino acids or oxidized Cys at the N-terminus of a substrate peptide and conjugates an arginine from an aminoacylated tRNAArg onto the N-terminus of the substrate peptide. This enzymatic reaction is carried out under physiological conditions and, in combination with Lys-C/Asp-N double digest, results in arginylated peptides with basic amino acids on both termini. RESULTS We demonstrate that in vitro arginylation of peptides using yeast arginyl tRNA protein transferase 1 (yATE1) is a robust enzymatic reaction, specific to only modifying N-terminal acidic amino acids. Precursors originating from arginylated peptides generally have an increased protonation state compared with their non-arginylated forms. Furthermore, the product ion spectra of arginylated peptides show near complete 2× fragment ladders within the same MS/MS spectrum using commonly available electrospray ionization peptide fragmentation modes. Unexpectedly, arginylated peptides generate complete y- and c-ion series using electron transfer dissociation (ETD) despite having an internal proline residue. CONCLUSIONS We introduce a rapid enzymatic method to generate peptides flanked on either terminus by basic amino acids, resulting in a rich, redundant MS/MS fragment pattern. © 2014 The Authors. Rapid Communications in Mass Spectrometry published by John Wiley & Sons Ltd. PMID:25380496

  19. Primary biliary cirrhosis is associated with a genetic variant in the 3’ flanking region of the CTLA4 gene

    PubMed Central

    Juran, Brian D.; Atkinson, Elizabeth J.; Schlicht, Erik M.; Fridley, Brooke L.; Lazaridis, Konstantinos N.

    2008-01-01

    Background and Aims Genetic variation is invoked as a strong component underlying primary biliary cirrhosis (PBC) and other autoimmune disorders. Data suggests that some of this genetic risk is shared, affecting function of the immune mechanisms controlling self tolerance. Cytotoxic T-lymphocyte antigen 4 (CTLA4) encodes a coinhibitory immunoreceptor that is a key regulator of self tolerance with established genetic associations to multiple autoimmune diseases, but conflicting evidence of involvement with PBC. We aimed to perform a more comprehensive assessment of CTLA4 genetic variation in PBC using a haplotype-tagging based approach. Methods Single nucleotide polymorphisms (SNPs) were genotyped in 402 PBC patients and 279 controls and evaluated for association with PBC, and with antimitochondrial antibody (AMA) status and prior orthotopic liver transplant (OLT) among the PBC patients, both individually and as inferred haplotypes, using logistic regression. Results All SNPs were in Hardy Weinberg Equilibrium. We identified a novel and relatively strong association between PBC and rs231725, a SNP in the 3’ flanking region of CTLA4 located outside of the area previously investigated in PBC. This SNP tags a common CTLA4 haplotype that contains a number of functionally implicated autoimmune CTLA4 SNPs, which was also found to be associated with PBC and to a lesser extent AMA status and prior OLT. Conclusions Our findings suggest that CTLA4 has an impact on the risk of PBC and possibly plays a role in influencing AMA development as well as progression to OLT among PBC patients. Replication in a suitable, independent PBC cohort is needed. PMID:18778710

  20. Ectopic T Cell Receptor-α Locus Control Region Activity in B Cells Is Suppressed by Direct Linkage to Two Flanking Genes at Once

    PubMed Central

    Andino, Blanca E.; Harrow, Faith; Erhard, Karl F.; Kovalovsky, Damian; Sant'Angelo, Derek B.; Ortiz, Benjamin D.

    2010-01-01

    The molecular mechanisms regulating the activity of the TCRα gene are required for the production of the circulating T cell repertoire. Elements of the mouse TCRα locus control region (LCR) play a role in these processes. We previously reported that TCRα LCR DNA supports a gene expression pattern that mimics proper thymus-stage, TCRα gene-like developmental regulation. It also produces transcription of linked reporter genes in peripheral T cells. However, TCRα LCR-driven transgenes display ectopic transcription in B cells in multiple reporter gene systems. The reasons for this important deviation from the normal TCRα gene regulation pattern are unclear. In its natural locus, two genes flank the TCRα LCR, TCRα (upstream) and Dad1 (downstream). We investigated the significance of this gene arrangement to TCRα LCR activity by examining transgenic mice bearing a construct where the LCR was flanked by two separate reporter genes. Surprisingly, the presence of a second, distinct, reporter gene downstream of the LCR virtually eliminated the ectopic B cell expression of the upstream reporter observed in earlier studies. Downstream reporter gene activity was unaffected by the presence of a second gene upstream of the LCR. Our findings indicate that a gene arrangement in which the TCRα LCR is flanked by two distinct transcription units helps to restrict its activity, selectively, on its 5′-flanking gene, the natural TCRα gene position with respect to the LCR. Consistent with these findings, a TCRα/Dad1 locus bacterial artificial chromosome dual-reporter construct did not display the ectopic upstream (TCRα) reporter expression in B cells previously reported for single TCRα transgenes. PMID:21124935

  1. Linkage disequilibrium in the insulin gene region is related to the exact number of repeat units present at the 5{prime} flanking polymorphism

    SciTech Connect

    McGinnis, R.E.; Spielman, R.S.

    1994-09-01

    Tandem DNA repeat units (RUs) located 5{prime} to the insulin (INS) gene give rise to a {open_quotes}5{prime} flanking polymorphism{close_quotes} (5{prime}FP) with minisatellite alleles belonging to 3 size classes. The shortest or {open_quotes}class 1{close_quotes} alleles (mean length of {approximately}40 RUs) are associated with insulin-dependent diabetes mellitus (IDDM), and the 5{prime}FP is one of several INS region loci in strong linkage disequilibrium with IDDM. We have amplified class 1 alleles and have determined the exact number of RUs in individual class 1 alleles found in parents of 50 IDDM families. We also obtained INS region haplotypes by typing two loci near tyrosine hydroxylase (TH) and two loci near insulin-like growth factor II (IGF2). We obtained these results: (1) Class 1 alleles (n=101) were found at every integer length from 30 to 44 RUs, the lengths of smallest and largest class 1 alleles observed. The allele frequency distribution was trimodal with peaks at 31, 40 and 42 RUs; 18%, 34% and 48% of the alleles belonged to the three components, respectively. (2) Allelic variation at each flanking locus was highly associated with the exact number of RUs present at the 5{prime}FP. Our results suggest that creation of new 5{prime}FP or other minisatellite haplotypes may be {open_quotes}constrained{close_quotes} in that flanking alleles usually become associated with a new minisatellite length different by only one or two RUs. Furthermore, since many flanking alleles were associated with a single narrow range of class 1 integer lengths, determining exact RU length may aid in visualizing linkage disequilibrium and allelic associations involving other minisatellite loci.

  2. The tsunami effects of a volcanic island flank collapse on a semi-enclosed basin: The Pico-São Jorge channel in the Azores archipelago

    NASA Astrophysics Data System (ADS)

    Quartau, R.; Omira, R.; Ramalho, I.; Baptista, M. A.; Mitchell, N. C.

    2015-12-01

    The Azores archipelago is a set of nine volcanic islands in the middle of the North Atlantic, close to the triple junction between the North American, Eurasian and African plates. Due to their location, the islands are seismic and volcanically active, which makes them especially vulnerable to these types of hazards that could eventually trigger flank collapses, capable of generating destructive tsunamis. However, solid evidence of large-scale flank collapses has only been found recently in Pico Island (Costa et al., 2014; Quartau et al., 2015). This study investigates for the first time the tsunami effects of a flank collapse of the northeastern subaerial slope of Pico Island that occurred more than 70 ka ago. We first reconstructed the pre-event sub-aerial morphology of the island, and then numerically model the flank failure involving an estimated volume of ~8 km3, its flow toward and under the sea of ~14 km, and the subsequent tsunami generation and propagation. The modelling suggests that the collapse of Pico created a mega-tsunami that significantly impacted the coast of adjacent São Jorge Island only after 7 minutes after generation, with wave run-up reaching a maximum of 50 m at some coastlines. Most of the tsunami energy became trapped in the semi-enclosed basin between Pico and São Jorge Islands, with only relatively little energy escaping to neighboring islands. Acknowledgments The author wishes to acknowledge the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 603839 (Project ASTARTE - Assessment, Strategy and Risk Reduction for Tsunamis in Europe)" for its major contribution for the success of this study. Publication supported by project FCT UID/GEO/50019/2013 - Instituto Dom Luiz. The author also acknowledges Fundação Luso-Americana para o Desenvolvimento for supporting the participation in the meeting.

  3. The role of the 5'-flanking sequence of a human tRNA(Glu) gene in modulation of its transcriptional activity in vitro.

    PubMed Central

    Gonos, E S; Goddard, J P

    1990-01-01

    The role of a tRNA-like structure within the 5'-flanking sequence of a human tRNA(Glu) gene in the modulation of its transcription in vitro by HeLa cell extracts has been investigated using several deletion mutants of a recombinant of the gene which lacked part or all of the tRNA-like structure. The transcriptional efficiency of four mutants was the same as that of the wild-type recombinant, two mutants had decreased transcriptional efficiency, one was more efficient, and one, lacking part of the 5' intragenic control region, was inactive. Correlation of the transcriptional efficiencies with the position and the size of the 5'-flanking sequence that was deleted indicated that the tRNA-like structure may be deleted without loss of transcriptional efficiency. Current models for the modulation of tRNA gene transcription by the 5'-flanking sequence are assessed in the light of the results obtained, and a potential model is presented. Images Fig. 2. Fig. 4. PMID:2268303

  4. Establishment of a polychlorinated biphenyl-dechlorinating microbial consortium, specific for doubly flanked chlorines, in a defined, sediment-free medium

    SciTech Connect

    Wu, Q.; Sowers, K.R.; May, H.D.

    2000-01-01

    Estuarine sediment from Charleston Harbor, South Carolina, was used as inoculum for the development of an anaerobic enrichment culture that specifically dechlorinates doubly flanked chlorines (i.e., chlorines bound to carbon that are flanked on both sides by other chlorine-carbon bonds) of polychlorinated biphenyls (PCBs). Dechlorination was restricted to the para chlorine in cultures enriched with 10 mM fumarate, 50 ppm (173 {micro}M) 2,3,4,5-tetrachlorobiphenyl, and no sediment. Initially the rate of dechlorination decreased upon the removal of sediment from the medium. However, the dechlorinating activity was sustainable, and following sequential transfer in a defined, sediment-free estuarine medium, the activity increased to levels near that observed with sediment. The culture was nonmethanogenic, and molybdate, ampicillin, chloramphenicol, neomycin, and streptomycin inhibited dechlorination activity; bromethanesulfonate and vancomycin did not. Addition of 17 PCB congeners indicated that the culture specifically removes double flanked chlorines, preferably in the para position, and does not attack ortho chlorines. This is the first microbial consortium shown to para or meta dechlorinate a PCB congener in a defined sediment-free medium. It is the second PCB-dechlorinating enrichment culture to be sustained in the absence of sediment, but its dechlorinating capabilities are entirely different from those of the other sediment-free PCB-dechlorinating culture, an ortho-dechlorinating consortium, and do not match any previously published Aroclor-dechlorinating patterns.

  5. Linkage disequilibrium in the insulin gene region: Size variation at the 5{prime} flanking polymorphism and bimodality among {open_quotes}Class I{close_quotes} alleles

    SciTech Connect

    McGinnis, R.E.; Spielman, R.S.

    1994-09-01

    The 5{prime} flanking polymorphism (5{prime}FP), a hypervariable region at the 5{prime} end of the insulin gene, has {open_quotes}class 1{close_quotes} alleles (650-900 bp long) that are in positive linkage disequilibrium with insulin-dependent diabetes mellitus (IDDM). The authors report that precise sizing of the 5{prime}FP yields a bimodal frequency distribution of class 1 allele lengths. Class 1 alleles belonging to the lower component (650-750 bp) of the bimodal distribution were somewhat more highly associated with IDDM than were alleles from the upper component (760-900 bp), but the difference was not statistically significant. They also examined 5{prime}FP length variation in relation to allelic variation at nearby polymorphisms. At biallelic RFLPs on both sides of the 5{prime}FP, they found that one allele exhibits near-total association with the upper component of the 5FP class 1 distribution. Such associations represent a little-known but potentially wide-spread form of linkage disequilibrium. In this type of disequilibrium, a flanking allele has near-complete association with a single mode of VNTR alleles whose lengths represent consecutive numbers of tandem repeats (CNTR). Such extreme disequilibrium between a CNTR mode and flanking alleles may originate and persist because length mutations at some VNTR loci usually add or delete only one or two repeat units. 22 refs., 5 figs., 6 tabs.

  6. Modification of the carboxy-terminal flanking region of a universal influenza epitope alters CD4+ T-cell repertoire selection

    PubMed Central

    Cole, David K.; Gallagher, Kathleen; Lemercier, Brigitte; Holland, Christopher J.; Junaid, Sayed; Hindley, James P.; Wynn, Katherine K.; Gostick, Emma; Sewell, Andrew K.; Gallimore, Awen M.; Ladell, Kristin; Price, David A.; Gougeon, Marie-Lise; Godkin, Andrew

    2012-01-01

    Human CD4+ αβ T cells are activated via T-cell receptor recognition of peptide epitopes presented by major histocompatibility complex (MHC) class II (MHC-II). The open ends of the MHC-II binding groove allow peptide epitopes to extend beyond a central nonamer core region at both the amino- and carboxy-terminus. We have previously found that these non-bound C-terminal residues can alter T cell activation in an MHC allele-transcending fashion, although the mechanism for this effect remained unclear. Here we show that modification of the C-terminal peptide-flanking region of an influenza hemagglutinin (HA305−320) epitope can alter T-cell receptor binding affinity, T-cell activation and repertoire selection of influenza-specific CD4+ T cells expanded from peripheral blood. These data provide the first demonstration that changes in the C-terminus of the peptide-flanking region can substantially alter T-cell receptor binding affinity, and indicate a mechanism through which peptide flanking residues could influence repertoire selection. PMID:22314361

  7. Morphotectonic architecture of the Transantarctic Mountains rift flank between the Royal Society Range and the Churchill Mountains based on geomorphic analysis

    USGS Publications Warehouse

    Demyanick, Elizabeth; Wilson, Terry J.

    2007-01-01

    Extensional forces within the Antarctic Plate have produced the Transantarctic Mountains rift-flank uplift along the West Antarctic rift margin. Large-scale linear morphologic features within the mountains are controlled by bedrock structure and can be recognized and mapped from satellite imagery and digital elevation models (DEMs). This study employed the Antarctic Digital Database DEM to obtain slope steepness and aspect maps of the Transantarctic Mountains (TAM) between the Royal Society Range and the Churchill Mountains, allowing definition of the position and orientation of the morphological axis of the rift-flank. The TAM axis, interpreted as a fault-controlled escarpment formed by coast-parallel retreat, provides a marker for the orientation of the faulted boundary between the TAM and the rift system. Changes in position and orientation of the TAM axis suggests the rift flank is segmented into tectonic blocks bounded by relay ramps and transverse accommodation zones. The transverse boundaries coincide with major outlet glaciers, supporting interpretation of rift structures between them. The pronounced morphological change across Byrd Glacier points to control by structures inherited from the Ross orogen.

  8. An EAV-HP insertion in 5' Flanking region of SLCO1B3 causes blue eggshell in the chicken.

    PubMed

    Wang, Zhepeng; Qu, Lujiang; Yao, Junfeng; Yang, Xiaolin; Li, Guangqi; Zhang, Yuanyuan; Li, Junying; Wang, Xiaotong; Bai, Jirong; Xu, Guiyun; Deng, Xuemei; Yang, Ning; Wu, Changxin

    2013-01-01

    The genetic determination of eggshell coloration has not been determined in birds. Here we report that the blue eggshell is caused by an EAV-HP insertion that promotes the expression of SLCO1B3 gene in the uterus (shell gland) of the oviduct in chicken. In this study, the genetic map location of the blue eggshell gene was refined by linkage analysis in an F(2) chicken population, and four candidate genes within the refined interval were subsequently tested for their expression levels in the shell gland of the uterus from blue-shelled and non-blue-shelled hens. SLCO1B3 gene was found to be the only one expressed in the uterus of blue-shelled hens but not in that of non-blue-shelled hens. Results from a pyrosequencing analysis showed that only the allele of SLCO1B3 from blue-shelled chickens was expressed in the uterus of heterozygous hens (O*LC/O*N). SLCO1B3 gene belongs to the organic anion transporting polypeptide (OATP) family; and the OATPs, functioning as membrane transporters, have been reported for the transportation of amphipathic organic compounds, including bile salt in mammals. We subsequently resequenced the whole genomic region of SLCO1B3 and discovered an EAV-HP insertion in the 5' flanking region of SLCO1B3. The EAV-HP insertion was found closely associated with blue eggshell phenotype following complete Mendelian segregation. In situ hybridization also demonstrated that the blue eggshell is associated with ectopic expression of SLCO1B3 in shell glands of uterus. Our finding strongly suggests that the EAV-HP insertion is the causative mutation for the blue eggshell phenotype. The insertion was also found in another Chinese blue-shelled breed and an American blue-shelled breed. In addition, we found that the insertion site in the blue-shelled chickens from Araucana is different from that in Chinese breeds, which implied independent integration events in the blue-shelled chickens from the two continents, providing a parallel evolutionary example at the

  9. On the influence of geological and cryospheric factors on slope instabilities in steep high-mountain flanks

    NASA Astrophysics Data System (ADS)

    Fischer, L.; Huggel, C.; Purves, R. S.; Amann, F.

    2009-04-01

    Slope stability of steep flanks in glacierised and permafrost-affected high-alpine regions is controlled by different factors, such as topography, geological-geotechnical conditions, hydrogeology, glaciation and permafrost. Changes in one or more factors may affect slope stability and eventually lead to rock fall events. Currently, cryospheric factors are most prone to changes. Based on the analysis of recent rock fall events, this study aims to provide new aspects for the understanding of the different factors and mechanisms which may affect the stability of high-mountain rock walls, especially in view of ongoing climatic change. The complexity of slope stability problems underlying high-mountain boundary conditions demands the implementation of multidisciplinary investigations and modelling methods. We report on an integrated assessment of the detachment zones of several recent rock fall events. Detailed site investigations were combined with comprehensive statistical analyses of rock fall events. As a case study the Tschierva rock fall event was back-calculated by means of the discrete element method (UDEC). Different parameters of the detachment zone such as the topography, lithological, geomechanical and hydrology characteristics, as well as glaciation and permafrost occurrence were investigated based on scientific field data and from imagery or meteorological data. Results from the slope stability modelling show that the glacier retreat strongly influences the stress field and causes an opening of pre-existing discontinuities in the bedrock. A second case study was performed for the Monte Rosa east face. Besides highly specified field and imagery investigations, high-resolution DTMs from LiDAR and digital photogrammetry were developed for detailed investigations of long-term topographic changes in glaciation and bedrock within the past 50 years. The results revealed the significant influence of glacier retreat on slope stability and important feedback

  10. Earthquakes and faults at Mt. Etna (Italy): time-dependent approach to the seismic hazard of the eastern flank

    NASA Astrophysics Data System (ADS)

    Peruzza, L.; Azzaro, R.; D'Amico, S.; Tuve', T.

    2009-04-01

    A time dependent approach to seismic hazard assessment, based on a renewal model using the Brownian Passage Time (BPT) distribution, has been applied to the best-known seismogenic faults at Mt. Etna volcano. These structures have been characterised by frequent coseismic surface displacement, and a long list of historically well-documented earthquakes occurred in the last 200 years (CMTE catalogue, Azzaro et al., 2000, 2002, 2006). Seismic hazard estimates, given in terms of earthquake rupture forecast, are conditioned to the time elapsed since the last event: impending events are expected on the S. Tecla Fault, and secondly on the Moscatello Fault, both involved in the highly active, geodynamic processes affecting the eastern flank of Mt. Etna. Mean recurrence time of major events is calibrated by merging the inter-event times observed at each fault; aperiodicity is tuned on b-values, following the approach proposed by Zoeller et al. (2008). Finally we compare these mean recurrence times with the values obtained by using only geometrical and kinematic information, as defined in Peruzza et al. (2008) for faults in Italy. Time-dependent hazard assessment is compared with the stationary assumption of seismicity, and validated in a retrospective forward model. Forecasted rates in a 5 years perspective (1st April 2009 to 1st April 2014), on magnitude bins compatible with macroseismic data are available for testing in the frame of the CSEP (Collaboratory for the study of Earthquake Predictability, www.cseptesting.org) project. Azzaro R., Barbano M.S., Antichi B., Rigano R.; 2000: Macroseismic catalogue of Mt. Etna earthquakes from 1832 to 1998. Acta Volcanol., con CD-ROM, 12 (1), 3-36. http://www.ct.ingv.it/Sismologia/macro/default.htm Azzaro R., D'Amico S., Mostaccio A., Scarfì L.; 2002: Terremoti con effetti macrosismici in Sicilia orientale - Calabria meridionale nel periodo Gennaio 1999 - Dicembre 2001. Quad. di Geof., 27, 1-59. Azzaro R., D'Amico S., Mostaccio A

  11. A 15 Mb large paracentric chromosome 21 inversion identified in Czech population through a pair of flanking duplications

    PubMed Central

    2014-01-01

    Background Inversions are balanced structural chromosome rearrangements, which can influence gene expression and the risk of unbalanced chromosome constitution in offspring. Many examples of inversion polymorphisms exist in human, affecting both heterochromatic regions and euchromatin. Results We describe a novel, 15 Mb long paracentric inversion, inv(21)(q21.1q22.11), affecting more than a third of human 21q. Despite of its length, the inversion cannot be detected using karyotyping due to similar band patterns on the normal and inverted chromosomes, and is therefore likely to escape attention. Its identification was aided by the repeated observation of the same pair of 150 kb long duplications present in cis on chromosome 21 in three Czech families subjected to microarray analysis. The finding prompted us to hypothesise that this co-occurrence of two remote duplications could be associated with an inversion of the intervening segment, and this speculation turned out to be right. The inversion was confirmed in a series of FISH experiments which also showed that the second copy of each of the duplications was always located at the opposite end of the inversion. The presence of the same pair of duplications in additional individuals reported in public databases indicates that the inversion may also be present in other populations. Three out of the total of about 4000 chromosomes 21 examined in our sample carried the duplications and were inverted, corresponding to carrier frequency of about 1/660. Although the breakpoints affect protein-coding genes, the occurrence of the inversion in normal parents and siblings of our patients and the occurrence of the duplications in unaffected controls in databases indicate that this rare variant is rather non-pathogenic. The inverted segment carried an identical shared haplotype in the three families studied. The haplotypes, however, diverged very rapidly in the flanking regions, possibly pointing to an ancient founder event at

  12. New Pressure Results from the Expedition 336 CORKs at North Pond, Western Flank of the Mid-Atlantic Ridge

    NASA Astrophysics Data System (ADS)

    Becker, K.; Villinger, H. W.; Davis, E. E.

    2014-12-01

    We report results from a nearly two-year record of pressure data from three CORK hydrogeological observatories in the ~8x15 km "North Pond" sedimented basin in ~7 Ma crust west of the mid-Atlantic Ridge at 23°N. The new data were recovered during operations with the ROV Jason from the German R/V Maria S. Merian in April of 2014. Two of the CORKs (in Holes U1382A and U1383C) had been installed during IODP Expedition 336 in fall of 2011, with an initial installment of 6-7 months data recovered in spring 2012, also by Jason from R/V Merian. The third hole, U1383B, was instrumented during the 2012 cruise with a "CORK-Lite" deployed by the ROV. All three installations monitor formation pressures in basement beneath the sediment pond. The new data confirm results of the first half-year of data, which suggested a slight formation overpressure (~10 kPa) relative to hydrostatic in the two full CORK installations. This was somewhat surprising given (a) the long history of downhole flow in DSDP Hole 395A that also penetrated basement beneath the sediment pond, and (b) prior observations at more thickly-sedimented eastern Pacific ridge flanks of formation underpressures in sites drilled into basement lows. The new results show a small phase lag and attenuation of formation tidal signals relative to seafloor tides that is the same in all three holes, which confirms that the CORKs are properly sealed at the seafloor. The phase lag and attenuation are also the same among three separate basement intervals in Hole U1383C, which suggests either that the entire drilled section is hydrogeologically well connected or that downhole packers between the intervals do not seal completely. We explore potential models to explain the slight observed overpressures. One possibility is that the geometry of the isolated sediment pond results in higher formation temperatures and less dense formation fluids immediately below the relatively impermeable sediment pond, such that surrounding cooler

  13. Conserved POU/OCT- and GATA-binding sites in 5'-flanking promoter region of mammalian WNT8B orthologs.

    PubMed

    Katoh, Masuko; Katoh, Masaru

    2007-05-01

    WNT family members are secreted-type glycoproteins regulating cell fate, planar cell polarity, cell adhesion, and cell movement. WNT signals are context-dependently transduced to the canonical pathway for the transcriptional up-regulation of MYC, CCND1, FGF20, JAG1, WISP1 and DKK1 genes, and also to the non-canonical pathway for the activation of RHOA, JNK, PKC, NFAT and NLK signaling cascades. We cloned and characterized the wild-type human WNT8B, while another group the aberrant human WNT8B with Gly230Ala and Arg284Leu amino-acid substitutions. Although WNT8B is undetectable in normal adult tissues by using Northern blot analyses, WNT8B is expressed in gastric cancer, pancreatic cancer, colorectal cancer, breast cancer, and embryonal tumors. Here, comparative integromics on WNT8B orthologs were investigated by using bioinformatics (Techint) and human intelligence (Humint). Cow Wnt8b gene was identified within NW_001494361.1 genome sequence. Predicted sequence XM_582222.3 was an artificial cow Wnt8b with aberrant prediction for the first exon. Cow Wnt8b complete coding sequence was found to encode a 350-amino-acid protein, which showed 96.9% total-amino-acid identity with human WNT8B. Comparative proteomics revealed that N-terminal signal peptide, 22 Cys residues, two Asn-linked glycosylation sites, Gly230, and Arg284 of human WNT8B were conserved among mammalian WNT8B orthologs. Comparative genomics revealed that POU/OCT- and GATA-binding sites in the 5'-flanking promoter region were conserved among human, chimpanzee, cow, mouse, and rat WNT8B orthologs. In silico expression analyses revealed that human WNT8B was expressed in embryoid body derived from embryonic stem (ES) cells, hepatocyte progenitors derived from ES cells, fetal brain, diffuse-type gastric cancer, colorectal cancer, prostate cancer, and ovarian fibrotheoma. Based on the expression profiles of POU and GATA family transcription factors, it was revealed that WNT8B expression in hepatocyte

  14. Isotopic characterization of mountain precipitation along the eastern flank of the Andes between 32.5 - 35°S

    NASA Astrophysics Data System (ADS)

    Hoke, G. D.; Aranibar, J. N.; Viale, M.; Araneo, D. C.; LLano, C. L.

    2011-12-01

    Data describing the isotopic composition of precipitation in the Andes are sparse: on the South American continent one IAEA Global Network of Isotopes in Precipitation (GNIP) station above 1500 m elevation exists south of La Paz. Better spatial density is necessary to improve our understanding of isotopes in mountain precipitation, which has implications for how to interpret isotopic information from the geologic record and the validation of isotope tracking modules in climate models. We present finding from two-years of quasi-monthly precipitation collection on the eastern flank of the Andes between 32.5 and 35°S latitude. A total of 123 samples were collected from 10 stations from Setember 2008 until September 2010. North of 33°S, the 2500 m average elevation Precordillera forms a steep front orographic barrier and the 2000 m elevation Uspallata Valley separates the Precordillera from the high Andes to the East. South of 33°S the Precordillera ends and the Andes return to a simple linear morphology. The low-leeward (eastern) side of the Andes receives predominately summer precipitation from convective storms, usually triggered by daytime upslope flow or synoptic-scale easterly flow over the Precordillera. Moving westward from the low-leeward side to the range crest, the influence of the easterly summer precipitation wanes and winter spillover precipitation from mid-latitude westerly storms beings to dominate. Our results show the local meteoric water line is slightly steeper (~0.5) than the global meteoric water line and a y-intercept of 14. The most negative δ18O values vary as much as 15 per mil seasonally, while averages weighted by precipitation amount show a strong cross-barrier (elevation) dependence. At these latitudes, the weighted average precipitation δ18O values show a significant deviation from river water near the range crest. The influence of the different moisture sources, from synoptic-scale easterly or westerly flow, is distinguished by

  15. Simulation of the Etna 2001 flank eruption with a steady-state numerical model of magma ascent

    NASA Astrophysics Data System (ADS)

    La Spina, Giuseppe; Burton, Mike; de'Michieli Vitturi, Mattia

    2015-04-01

    Volcanoes exhibit a wide range of eruption styles, from relatively slow effusive eruptions, generating lava flows and lava domes, to explosive eruptions, in which very large volumes of fragmented magma and volcanic gas are ejected high into the atmosphere. Magma ascent dynamics in a volcanic conduit play a key role in determining the eruptive style of a volcano. However, due to the lack of direct observations in the conduit itself, numerical models, constrained with observational data, provide invaluable tools for quantitative insights into the complex magma ascent processes. We have developed a 1D steady-state multiphase multicomponent gas-magma-solid mathematical model, consisting of a set of non-linear partial differential and constitutive equations. The governing equations used in this work are designed to model multiphase fluid with disequilibrium processes, represented through the formalism of thermodynamically compatible hyperbolic systems as a system of conservative partial differential equations with relaxation terms. This numerical model has been used to reproduce the 2001 flank eruption at mount Etna. During this eruption, seven fissures at different altitude were active, showing different eruptive styles: fire fountains, Strombolian activities and lava effusions. From a mineralogical point of view, two different lavas were erupted. The vent higher than 2600 m a.s.l. (hereafter Upper vents, UV) erupted plagioclase-rich magma with an high crystal content. On the other hand, the vents located at 2550 and 2100 m a.s.l. (hereafter Lower vents, LV) produced a plagioclase-poor magma with a lower crystal content than UV magmas. With our numerical model we have investigated both eruptive events at UV and LV. Using the estimation for volume flow rate and for crystal content we are able to constraint the conduit radius and the temperature of the magma chamber. Furthermore, our numerical results indicate that UV and LV magmas are originated from the same magma, but

  16. Genomic organization and gene expression of the multiple globins in Atlantic cod: conservation of globin-flanking genes in chordates infers the origin of the vertebrate globin clusters

    PubMed Central

    2010-01-01

    Background The vertebrate globin genes encoding the α- and β-subunits of the tetrameric hemoglobins are clustered at two unlinked loci. The highly conserved linear order of the genes flanking the hemoglobins provides a strong anchor for inferring common ancestry of the globin clusters. In fish, the number of α-β-linked globin genes varies considerably between different sublineages and seems to be related to prevailing physico-chemical conditions. Draft sequences of the Atlantic cod genome enabled us to determine the genomic organization of the globin repertoire in this marine species that copes with fluctuating environments of the temperate and Arctic regions. Results The Atlantic cod genome was shown to contain 14 globin genes, including nine hemoglobin genes organized in two unlinked clusters designated β5-α1-β1-α4 and β3-β4-α2-α3-β2. The diverged cod hemoglobin genes displayed different expression levels in adult fish, and tetrameric hemoglobins with or without a Root effect were predicted. The novel finding of maternally inherited hemoglobin mRNAs is consistent with a potential role played by fish hemoglobins in the non-specific immune response. In silico analysis of the six teleost genomes available showed that the two α-β globin clusters are flanked by paralogs of five duplicated genes, in agreement with the proposed teleost-specific duplication of the ancestral vertebrate globin cluster. Screening the genome of extant urochordate and cephalochordate species for conserved globin-flanking genes revealed linkage of RHBDF1, MPG and ARHGAP17 to globin genes in the tunicate Ciona intestinalis, while these genes together with LCMT are closely positioned in amphioxus (Branchiostoma floridae), but seem to be unlinked to the multiple globin genes identified in this species. Conclusion The plasticity of Atlantic cod to variable environmental conditions probably involves the expression of multiple globins with potentially different properties. The

  17. High-energy deposits newly recognized in Hawaii Island (South Point): a catastrophic tsunami generated by South Kona or Kalae flank collapse?

    NASA Astrophysics Data System (ADS)

    Marques, F. O.; Hildenbrand, A.; McMurtry, G. M.

    2012-12-01

    Most of the population and economic activity on Earth is concentrated in coastal areas. Tsunamis, in particular, represent a major threat, because they can travel great distances and impact the far surrounding shorelines within a few hours and cause considerable damage. Two main geological processes can generate destructive tsunamis: (1) high-magnitude earthquakes within the oceans, mostly along active margins, which can generate long-wavelength, low amplitude waves; and (2) giant mass-movements, such as catastrophic flank failure at oceanic volcanoes, which can instantaneously mobilize great amounts of material (several hundreds of km3) and generate high amplitude, medium-wavelength tsunamis. The Hawaiian volcanic chain has been affected by the largest landslides on Earth. Big Island, especially, has faced several catastrophic episodes of flank destabilization, the number, the amplitude and the age of which remain controversial. Knowing that there were flank collapses in South Kona and Kalae, we went to South Point to look for onland evidence of the collapse(s) and related tsunami(s), and found a deposit composed of polygenetic clasts, from mm3 to several m3 in size, mostly angular to sub-rounded, with a sandy to silty matrix. The deposit is covered by pyroclasts (the Pahala ash?), which seem to have been locally remobilized to fill in the spaces in the underlying conglomeratic deposit. The absence of a continuous indurate cement precludes an inland origin for the sedimentary deposit. Moreover, the South Point deposit lies on a flat platform far from the main topographic relief of the Mauna Loa and Kilauea volcanoes. Emplacement of the ash layers covering the deposits requires a highly explosive eruption, which we attribute to pressure release driven by the collapse. Presently the deposit is lying at an altitude of ca. 10 m, but in the past it was higher, since the island has experienced significant ongoing subsidence. From previous estimates of the age of the

  18. Pressure-induced isomerization of a heterometallic rhodium-gold cluster compound: (Rh sub 2 (. mu. -Cl) sub 2 (CNC sub 8 H sub 9 ) sub 4 (. mu. -AuPPh sub 3 )) sub 2 (PF sub 6 ) sub 2

    SciTech Connect

    Bray, K.L.; Drickamer, H.G.; Shapley, J.R. ); Mingos, D.M.P.; Watson, M.J. )

    1991-02-20

    Mingos et al. have prepared two isomers of the cluster compound (Rh{sub 2}(mu-Cl{sub 2})(CNC{sub 8}H{sub 9}){sub 4}(mu-AuPPh{sub 3})){sub 2}(PF{sub 6}){sub 2} and have characterized these isomers using single crystal x-ray techniques. The volumes per cluster cation were found to be very similar for both isomers, 1,430 and 1,413 angstroms, and the Rh-Rh bond lengths were found to be 3.262 and 3.008 angstroms for the same isomer. The cluster skeletal geometries were found to differ only at an interior link, and applied pressure appeared to induce a conformational transition around this bond.

  19. Hawaiian Volcano Flank Stability Appraised From Strength Testing the Hawaiian Scientific Drilling Project's (HSDP) 3.1-km Drill Core

    NASA Astrophysics Data System (ADS)

    Thompson, N.; Watters, R. J.; Schiffman, P.

    2005-12-01

    the means of the basaltic flows, intrusive and pillow lava values. The test results imply that shallow rotational slumps that develop within the upper few kilometers of spreading Hawai'ian volcanoes within low strength, poorly-consolidated, smectite-rich hyaloclastites are similar to those we have found from the incipient and smectitic alteration zones of the HSDP cores. Deeper slumps might be directed through over-pressured pillow lava units as a result of the stronger pillow lava units permitting deeper failure surfaces to develop. Petrographically the Mauna Kea hyaloclastites appear similar to those from actively spreading Hawai'ian shield volcanoes. Alteration processes apparently affect the strength of these hyaloclastites. In the shallower zones of incipient and smectitic alteration, hyaloclastites generally retain their high primary porosities. In the deeper, palagonitic zone of alteration, the hyaloclastites gain both compressive and shear strength, primarily through consolidation and zeolitic cementation. The marked strength contrast between hyaloclastites, and the lavas that overlie and underlie them is significant, and may be a primary factor in localizing the destabilization of the flanks of Hawaiian volcanoes.

  20. Geomorphic disequilibrium in the Eastern Korean Peninsula: Possible evidence for reactivation of a rift-flank margin

    NASA Astrophysics Data System (ADS)

    Kim, Dong-Eun; Seong, Yeong Bae; Byun, Jongmin; Weber, John; Min, Kyoungwon

    2016-02-01

    -level changes. Our 1-D modeling of knickpoint propagation suggests that tectonic disturbance is the factor most likely to produce knickzones in the study area, raising the possibility that erosional signals caused by late-Pleistocene tectonic disturbance affected channel gradients, but that the knickpoints have not yet propagated through the entire catchment area. Our results suggest that the eastern part of the Korean Peninsula is approaching, but has not completely reached, a geomorphic steady-state, and that transient conditions have been induced by reactivation of the rift-flank margin no later than the late Pleistocene, causing tilting of the central Korean Peninsula to the west at a rate of 7.0 × 10- 10 m/m per year over the past ~ 125 ka.