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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. 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 ...

  3. 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.

  4. 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,…

  5. Carney complex (CNC).

    PubMed

    Bertherat, Jérôme

    2006-01-01

    The Carney complex (CNC) is a dominantly inherited syndrome characterized by spotty skin pigmentation, endocrine overactivity and myxomas. Skin pigmentation anomalies include lentigines and blue naevi. The most common endocrine gland manifestations are acromegaly, thyroid and testicular tumors, and adrenocorticotropic hormone (ACTH)-independent Cushing's syndrome due to primary pigmented nodular adrenocortical disease (PPNAD). PPNAD, a rare cause of Cushing's syndrome, is due to primary bilateral adrenal defect that can be also observed in some patients without other CNC manifestations or familial history of the disease. Myxomas can be observed in the heart, skin and breast. Cardiac myxomas can develop in any cardiac chamber and may be multiple. One of the putative CNC genes located on 17q22-24, (PRKAR1A), has been identified to encode the regulatory subunit (R1A) of protein kinase A. Heterozygous inactivating mutations of PRKAR1A were reported initially in 45 to 65% of CNC index cases, and may be present in about 80% of the CNC families presenting mainly with Cushing's syndrome. PRKAR1A is a key component of the cAMP signaling pathway that has been implicated in endocrine tumorigenesis and could, at least partly, function as a tumor suppressor gene. Genetic analysis should be proposed to all CNC index cases. Patients with CNC or with a genetic predisposition to CNC should have regular screening for manifestations of the disease. Clinical work-up for all the manifestations of CNC should be performed at least once a year in all patients and should start in infancy. Cardiac myxomas require surgical removal. Treatment of the other manifestations of CNC should be discussed and may include follow-up, surgery, or medical treatment depending on the location of the tumor, its size, the existence of clinical signs of tumor mass or hormonal excess, and the suspicion of malignancy. Bilateral adrenalectomy is the most common treatment for Cushing's syndrome due to PPNAD. PMID

  6. 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)

  7. 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.

  8. 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.

  9. 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.

  10. 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…

  11. 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.

  12. 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.

  13. 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.

  14. Backlash Decrease System of Reducers/Gearboxes in Feed Kinematical Linkage Structure of CNC Machine Tools

    NASA Astrophysics Data System (ADS)

    Stan, G.

    2016-08-01

    Feed kinematic linkages of the CNC machine tools are built in camted cycle (closed loop) and their structures include reducers/gearboxes. as well. Because of the mechanical backlash between the flanks of the teeth of gearings, disturbances occur in the performance of a kinematic linkage as a whole (in terms of speed and position loops), thus leading to instability. This work presents a new system for decreasing the mechanical backlash that is based on a new type of cylindrical gearings with tapered teeth, allowing the backlash adjustment between the flanks of the joint teeth. The modality of acting in terms of decreasing the backlash on a reducer in the structure of a feed kinematic linkage is also detailed.

  15. 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.

  16. Seasonal flank alopecia in affenpinschers.

    PubMed

    Waldman, L

    1995-06-01

    Two intact, distantly related, female affenpinschers, belonging to a breeder, were referred in March 1993 for the investigation of bilateral, symmetrical flank alopecia in one bitch and bilateral, symmetrical flank, dorsum and tail alopecia in the other; the alopecia occurred from November to May and January to May, respectively. During that period the bitches were kept in a conservatory without artificial heating or lighting. The owner reported that the mother of one bitch had had bilateral, symmetrical flank alopecia during one winter when kept in the conservatory, but was normal the following winter when kept in the house. Three other females and a male exhibited the same clinical signs when kept in the conservatory during the winter. Seasonal flank alopecia has not previously been reported in affenpinschers.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. 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

  2. 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…

  3. 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,…

  4. Heat Shield Flank Close Up

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This image from NASA's Mars Exploration Rover Opportunity features an up-close view of the flank piece of the rover's broken heat shield.

    The rover spent 36 sols investigating how the severe heating during entry through the atmosphere affected the heat shield. The most obvious is the fact that the heat shield inverted upon impact. Overall, engineers were interested in evaluating the performance of the heat shield's thermal protection system.

    This is the the panormamic camera team's best current attempt at generating a 'true color' view of what this scene would look like if viewed by a human on Mars. It was generated from a mathematical combination of six calibrated, left-eye panoramic camera images acquired around 3:07 p.m. local solar time on Opportunity's sol 331 (Dec. 28, 2004) using filters ranging in wavelengths from 430 to 750 nanometers.

  5. 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.

  6. Robustness of thermal error compensation model of CNC machine tool

    NASA Astrophysics Data System (ADS)

    Lang, Xianli; Miao, Enming; Gong, Yayun; Niu, Pengcheng; Xu, Zhishang

    2013-01-01

    Thermal error is the major factor in restricting the accuracy of CNC machining. The modeling accuracy is the key of thermal error compensation which can achieve precision machining of CNC machine tool. The traditional thermal error compensation models mostly focus on the fitting accuracy without considering the robustness of the models, it makes the research results into practice is difficult. In this paper, the experiment of model robustness is done in different spinde speeds of leaderway V-450 machine tool. Combining fuzzy clustering and grey relevance selects temperature-sensitive points of thermal error. Using multiple linear regression model (MLR) and distributed lag model (DL) establishes model of the multi-batch experimental data and then gives robustness analysis, demonstrates the difference between fitting precision and prediction precision in engineering application, and provides a reference method to choose thermal error compensation model of CNC machine tool in the practical engineering application.

  7. 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

  8. Colored neon flanks and line gap enhancement.

    PubMed

    Redies, C; Spillmann, L; Kunz, K

    1984-01-01

    When a colored line connects two black (or differently colored) lines across a gap, colored neon flanks are seen on either side of it. These flanks extend over gap sizes of 50 min arc foveally and are not explained by Bezold-type assimilation. They may be elicited by black lines as short as 6 min arc adjoining the colored line at each end. To maximize these flanks, the black and colored lines must appear linearly continuous. Nonaligned junctions weaken the effect and an angular tilt of more than 40 dog destroys it. In this and other respects, (local) neon flanks are similar to van Tuijl's (global) neon color spreading (1975). Both phenomena have analogs in brightness perception. We propose that neon spreading is a lateral extension of neon flanks across the empty space between them, and discuss similarities of these effects with other brightness illusions (Schumann, Prandtl, Ehrenstein). For this group of illusions the term "line gap enhancement" is introduced to imply perceptual enhancement of changes in brightness and/or color along lines. Correspondences between the psychophysical properties and structural prerequisites for line gap enhancement on one hand and neuronal response properties of end-zone inhibited (hypercomplex) cortical cells on the other are discussed.

  9. Calibration of CNC milling machine by direct method

    NASA Astrophysics Data System (ADS)

    Khan, Abdul Wahid; Chen, Wuyi

    2008-12-01

    Calibration refers to the system of quantity value determination of instruments, equipments and test devices according to industrial requirement, based on metrological characteristics. In present research critical parameter which affects the accuracy and product quality of a CNC milling machine, was investigated and quantified by using direct method. These parameters consist of position dependent or position independent parameters, like linear displacement errors, angular errors of linear axes, straightness error of linear axes and squareness error between the axes. Repeatability, lead screw and resolution error of the CNC milling machine were also quantified to provide additional information to the user, because in absence of this additional information a misconception persists causing a major contributor to the inaccuracy and quality of the product. Parameters were measured and quantified by using a laser interferometer and artifacts as working standards under controlled environmental conditions on a manufacturing CNC milling machine. Polynomial regression analyses were carried out for finding the coefficients to predict the errors at each and every desired position which is quite useful for compensation and enhancing the accuracy of a machine system. Machine accuracy detailed chart was also made to assess and assure the accuracy, capability or for accuracy monitoring of the CNC milling machine

  10. Linear positioning laser calibration setup of CNC machine tools

    NASA Astrophysics Data System (ADS)

    Sui, Xiulin; Yang, Congjing

    2002-10-01

    The linear positioning laser calibration setup of CNC machine tools is capable of executing machine tool laser calibraiotn and backlash compensation. Using this setup, hole locations on CNC machien tools will be correct and machien tool geometry will be evaluated and adjusted. Machien tool laser calibration and backlash compensation is a simple and straightforward process. First the setup is to 'find' the stroke limits of the axis. Then the laser head is then brought into correct alignment. Second is to move the machine axis to the other extreme, the laser head is now aligned, using rotation and elevation adjustments. Finally the machine is moved to the start position and final alignment is verified. The stroke of the machine, and the machine compensation interval dictate the amount of data required for each axis. These factors determine the amount of time required for a through compensation of the linear positioning accuracy. The Laser Calibrator System monitors the material temperature and the air density; this takes into consideration machine thermal growth and laser beam frequency. This linear positioning laser calibration setup can be used on CNC machine tools, CNC lathes, horizontal centers and vertical machining centers.

  11. 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…

  12. 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…

  13. 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.

  14. 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

  15. 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.

  16. 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 .

  17. 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.

  18. Microbial life in ridge flank crustal fluids.

    PubMed

    Huber, Julie A; Johnson, H Paul; Butterfield, David A; Baross, John A

    2006-01-01

    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 north-east 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.

  19. Constitutive activation of Drosophila CncC transcription factor reduces lipid formation in the fat body.

    PubMed

    Karim, M Rezaul; Taniguchi, Hiroaki; Kobayashi, Akira

    2015-08-01

    Accumulating evidence indicates that the vertebrate stress-response transcription factors Nrf1 and Nrf2 are involved in hepatic lipid metabolism. However, the underlying molecular mechanisms of Nrf1-and Nrf2-mediated lipid metabolism remain unclear. To elucidate the precise roles of Nrfs in this process, we analyzed the physiological role of CncC in lipid metabolism as a Drosophila model for vertebrate Nrf1 and Nrf2. We first examined whether CncC activity is repressed under physiological conditions through a species-conserved NHB1 (N-terminal homology box 1) domain, similar to that observed for Nrf1. Deletion of the NHB1 domain (CncCΔN) led to CncC-mediated rough-eye phenotypes and the induced expression of the CncC target gene gstD1 both in vivo and in vitro. Thus, we decided to explore how CncCΔN overexpression affects the formation of the fat body, which is the major lipid storage organ. Intriguingly, CncCΔN caused a significant reduction in lipid droplet size and triglyceride (TG) levels in the fat body compared to wild type. We found that CncCΔN induced a number of genes related to innate immunity that might have an effect on the regulation of cellular lipid storage. Our study provides new insights into the regulatory mechanism of CncC and its role in lipid homeostasis.

  20. 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).

  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. 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…

  3. Reducing maintenance costs in agreement with CNC machine tools reliability

    NASA Astrophysics Data System (ADS)

    Ungureanu, A. L.; Stan, G.; Butunoi, P. A.

    2016-08-01

    Aligning maintenance strategy with reliability is a challenge due to the need to find an optimal balance between them. Because the various methods described in the relevant literature involve laborious calculations or use of software that can be costly, this paper proposes a method that is easier to implement on CNC machine tools. The new method, called the Consequence of Failure Analysis (CFA) is based on technical and economic optimization, aimed at obtaining a level of required performance with minimum investment and maintenance costs.

  4. 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.

  5. Stable reconnection at the dusk flank magnetopause

    NASA Astrophysics Data System (ADS)

    Gomez, R. G.; Vines, S. K.; Fuselier, S. A.; Cassak, P. A.; Strangeway, R. J.; Petrinec, S. M.; Burch, J. L.; Trattner, K. J.; Russell, C. T.; Torbert, R. B.; Pollock, C.; Young, D. T.; Lewis, W. S.; Mukherjee, J.

    2016-09-01

    The dusk flank magnetopause was surveyed with instruments on board the Magnetospheric Multiscale (MMS) spacecraft on 28 August 2015 between 13:55 UT and 14:15 UT during a period of persistent southward interplanetary magnetic field (IMF) with varying dawn-dusk component. Plasma measurements (500 eV electrons, > 2 keV ions) revealed the existence of at least one active reconnection region that persisted throughout the interval. The reconnection region convected equatorward despite the poleward and tailward magnetosheath flow, which ranged from slightly sub-Alfvénic to slightly super-Alfvénic throughout the interval. These results suggest that magnetic reconnection moved in response to changes in the IMF clock angle rather than the magnetosheath flow, which is corroborated using predictions of the maximum magnetic shear model.

  6. 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.

  7. Preparation of CNC-dispersed Fe3O4 nanoparticles and their application in conductive paper.

    PubMed

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

    2015-08-01

    Well-dispersed Fe3O4 nanoparticles (NPs) were synthesized by a co-precipitation method in the presence of cellulose nano-crystals (CNC) as the template. The thus prepared Fe3O4 NPs were then used as a coating agent for the preparation of conductive paper. Fourier transform infrared spectroscopy (FTIR) results revealed that the Fe3O4 NPs were immobilized on the CNC through interactions between the hydroxyl groups of CNC and Fe3O4. Scanning transmission electron microscopy (STEM) images showed that the Fe3O4 NPs prepared in the presence of CNC can be dispersed in the CNC network, while the Fe3O4 NPs prepared in the absence of CNC tended to aggregate in aqueous solutions. The conductivity of the Fe3O4 NPs coated paper can reach to 0.0269 S/m at the coating amount of 14.75 g/m(2) Fe3O4/CNC nanocomposites. Therefore, the thus obtained coated paper can be potentially used as anti-static packaging material in the packaging field.

  8. Prepolishing on a CNC platform with bound abrasive contour tools

    NASA Astrophysics Data System (ADS)

    Schoeffler, Adrienne E.; Gregg, Leslie L.; Schoen, John M.; Fess, Edward M.; Hakiel, Michael; Jacobs, Stephen D.

    2003-05-01

    Deterministic microgrinding (DMG) of optical glasses and ceramics is the commercial manufacturing process of choice to shape glass surfaces prior to final finishing. This process employs rigid bound matrix diamond tooling resulting in surface roughness values of 3-5μm peak to valley and 100-400nm rms, as well as mid-spatial frequency tool marks that require subsequent removal in secondary finishing steps. The ability to pre-polish optical surfaces within the grinding platform would reduce final finishing process times. Bound abrasive contour wheels containing cerium oxide, alumina or zirconia abrasives were constructed with an epoxy matrix. The effects of abrasive type, composition, and erosion promoters were examined for tool hardness (Shore D), and tested with commercial optical glasses in an Optipro CNC grinding platform. Metrology protocols were developed to examine tool wear and subsequent surface roughness. Work is directed to demonstrating effective material removal, improved surface roughness and cutter mark removal.

  9. Isolation of tetranucleotide repeat polymorphisms flanking the BRCA1 gene

    SciTech Connect

    Bennett-Baker, P.E.; Kiousis, S.; King, S.E.

    1996-02-15

    This article reports on the isolation of tetranucleotide repeat polymorphisms which flank the BRCA1 gene on human chromosome 17. BRCA1 has been linked to both hereditary breast and ovarian cancer. Fifteen new short tandem repeat polymorphisms (STRPs) flanking the BRCA1 locus are reported. 18 refs., 2 figs., 1 tab.

  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. 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

  12. 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.

  13. 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.

  14. 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.

  15. Isolation of sequences flanking Ac insertion sites by Ac casting.

    PubMed

    Wang, Dafang; Peterson, Thomas

    2013-01-01

    Localizing Ac insertions is a fundamental task in studying Ac-induced mutation and chromosomal rearrangements involving Ac elements. Researchers may sometimes be faced with the situation in which the sequence flanking one side of an Ac/Ds element is known, but the other flank is unknown. Or, a researcher may have a small sequence surrounding the Ac/Ds insertion site and needs to obtain additional flanking genomic sequences. One way to rapidly clone unknown Ac/Ds flanking sequences is via a PCR-based method termed Ac casting. This approach utilizes the somatic transposition activity of Ac during plant development, and provides an efficient means for short-range genome walking. Here we describe the principle of Ac casting, and show how it can be applied to isolate Ac macrotransposon insertion sites.

  16. 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

  17. 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

  18. 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

  19. Detail view of fireplace and mantel, and flanking columns, in ...

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

    Detail view of fireplace and mantel, and flanking columns, in first floor main room, looking from the southwest - National Park Seminary, Swiss Chalet, 2802 Woodstock Avenue, Silver Spring, Montgomery County, MD

  20. 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

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. Physical Parameters of the Overcontact Binary AH Cnc in the Old Open Cluster M 67

    NASA Astrophysics Data System (ADS)

    Yakut, K.; Aerts, C.

    2006-04-01

    We present a photometric study of the overcontact binary AH Cnc. The CCD observations were done with the Russian-Turkish 1.5 m telescope and the light-curve was solved with the Wilson-Devinney code. The physical parameters of the components have been deduced as M1 = 1.22 Msun, M2 = 0.20 Msun, R1 = 1.37 Rsun, R2 = 0.66 Rsun, L1 = 2.65 Lsun and L2 = 0.63 Lsun from the obtained orbital parameters and the distance modules of M 67. AH Cnc has been compared with similar systems in the Hertzsprung-Russell diagram.

  14. 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.

  15. West Flank Coso FORGE Magnetotelluric 3D Data

    DOE Data Explorer

    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.

  16. 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

  17. 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.

  18. 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

  19. 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

  20. 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…

  1. 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.

  2. 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…

  3. 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…

  4. 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…

  5. 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...

  6. 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

  7. 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.

  8. 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.

  9. Flank collapses and tsunami hazard in the Antilles Arc

    NASA Astrophysics Data System (ADS)

    Teeuw, R.; Rust, D.; Solana, C.; Dewdney, C.; Robertson, R.

    2009-04-01

    We highlight potentially tsunamigenic volcanic flank instability on the north coast of Dominica in the Lesser Antilles arc. 3-D views from Google Earth were key to the initial recognition of this hazardous terrain. Seismic, bathymetric and geomorphological data suggest that this coast is bounded by an active fault structure, with the relatively up-thrown flank displaying evidence of both shallow translational and deep-seated rotational slope instability. A probable landslide block of ~1 M tonnes on the seaward margin of the instability complex has large tension cracks on its upslope margin, clearly visible on Quickbird satellite imagery and X-band SRTM digital elevation models . Failure of this block could destabilise a larger adjacent upslope block (~ 3 M tonnes). Preliminary calculations indicate that landslides at these scales could trigger tsunami waves, locally reaching up to 4 m in height, with the greatest hazard along the southern coast of Guadeloupe, 30-40 km to the north of Dominica.

  10. Changes in quantitative norepinephrine levels in delayed pig flank flaps.

    PubMed

    Cutting, C; Bumsted, R; Bardach, J; Mooney, M; Johnson, S

    1982-04-01

    A quantitative norepinephrine assay was used to follow tissue norepinephrine concentrations serially in bipedicle delayed pig flank flaps. In contrast to a previous study by Palmer, norepinephrine concentration decreased significantly after 24 hr, but then gradually returned to normal at 10 days. This suggests that the pig flank flap maintains much of its adrenergic innervation following bipedicle delay. It appears unlikely that adrenergic denervation explains the delay phenomenon in this model. The combined results of this study and others suggest that the degree of adrenergic denervation of a flap is determined by the anatomic layout of the flap with respect to the underlying cutaneous adrenergic neural anatomy. This experiment suggests that the effectiveness of adrenergic blocking agents in improving flap survival is dependent on the degree of adrenergic denervation of the flap.

  11. 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.

  12. Geomorphology of the north flank of the Uinta Mountains

    USGS Publications Warehouse

    Bradley, W.H.

    1936-01-01

    beds now form hogbacks ranked along the sides of the fold. In places large faults, approximating the regional strike, cut these steeply inclined beds. Gently warped Tertiary sediments, mostly of Eocene age, fill the large Green River Basin, which lies north of the range, to a depth of several thousand feet and lap up on the flanks of the mountains, from which they were chiefly derived.

  13. 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.

  14. 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.

  15. 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.

  16. Basic leucine zipper protein Cnc-C is a substrate and transcriptional regulator of the Drosophila 26S proteasome.

    PubMed

    Grimberg, Kristian Björk; Beskow, Anne; Lundin, Daniel; Davis, Monica M; Young, Patrick

    2011-02-01

    While the 26S proteasome is a key proteolytic complex, little is known about how proteasome levels are maintained in higher eukaryotic cells. Here we describe an RNA interference (RNAi) screen of Drosophila melanogaster that was used to identify transcription factors that may play a role in maintaining levels of the 26S proteasome. We used an RNAi library against 993 Drosophila transcription factor genes to identify genes whose suppression in Schneider 2 cells stabilized a ubiquitin-green fluorescent protein reporter protein. This screen identified Cnc (cap 'n' collar [CNC]; basic region leucine zipper) as a candidate transcriptional regulator of proteasome component expression. In fact, 20S proteasome activity was reduced in cells depleted of cnc. Immunoblot assays against proteasome components revealed a general decline in both 19S regulatory complex and 20S proteasome subunits after RNAi depletion of this transcription factor. Transcript-specific silencing revealed that the longest of the seven transcripts for the cnc gene, cnc-C, was needed for proteasome and p97 ATPase production. Quantitative reverse transcription-PCR confirmed the role of Cnc-C in activation of transcription of genes encoding proteasome components. Expression of a V5-His-tagged form of Cnc-C revealed that the transcription factor is itself a proteasome substrate that is stabilized when the proteasome is inhibited. We propose that this single cnc gene in Drosophila resembles the ancestral gene family of mammalian nuclear factor erythroid-derived 2-related transcription factors, which are essential in regulating oxidative stress and proteolysis.

  17. Basic Leucine Zipper Protein Cnc-C Is a Substrate and Transcriptional Regulator of the Drosophila 26S Proteasome▿ †

    PubMed Central

    Grimberg, Kristian Björk; Beskow, Anne; Lundin, Daniel; Davis, Monica M.; Young, Patrick

    2011-01-01

    While the 26S proteasome is a key proteolytic complex, little is known about how proteasome levels are maintained in higher eukaryotic cells. Here we describe an RNA interference (RNAi) screen of Drosophila melanogaster that was used to identify transcription factors that may play a role in maintaining levels of the 26S proteasome. We used an RNAi library against 993 Drosophila transcription factor genes to identify genes whose suppression in Schneider 2 cells stabilized a ubiquitin-green fluorescent protein reporter protein. This screen identified Cnc (cap 'n’ collar [CNC]; basic region leucine zipper) as a candidate transcriptional regulator of proteasome component expression. In fact, 20S proteasome activity was reduced in cells depleted of cnc. Immunoblot assays against proteasome components revealed a general decline in both 19S regulatory complex and 20S proteasome subunits after RNAi depletion of this transcription factor. Transcript-specific silencing revealed that the longest of the seven transcripts for the cnc gene, cnc-C, was needed for proteasome and p97 ATPase production. Quantitative reverse transcription-PCR confirmed the role of Cnc-C in activation of transcription of genes encoding proteasome components. Expression of a V5-His-tagged form of Cnc-C revealed that the transcription factor is itself a proteasome substrate that is stabilized when the proteasome is inhibited. We propose that this single cnc gene in Drosophila resembles the ancestral gene family of mammalian nuclear factor erythroid-derived 2-related transcription factors, which are essential in regulating oxidative stress and proteolysis. PMID:21149573

  18. Analogue modelling of flank dynamics at Mount Etna, Italy

    NASA Astrophysics Data System (ADS)

    Norini, Gianluca; Acocella, Valerio

    2010-05-01

    Mount Etna, Italy, is characterized by the instability of its East and South flanks. Factors governing this flank instability are still matter of debate. We investigate the role of different possible factors on flank instability, using analogue models. The apparatus consists of a cone and base made of granular material, simulating the volcanic edifice and its basement, respectively. The granular material we use is a mixture of low cohesion silica sand and high cohesion crushed silica powder. Alternated layers with different cohesion are used to account for differences in the crustal structure of the basement, in terms of cohesion and permeability. The geometry of the experiments is designated to simulate the topographic and bathymetric gradients at the base of the volcano. Injections of high viscosity silicone putty and low viscosity vegetable oil are used to model the inflation of reservoirs below the volcano and the emplacement of dikes, respectively. Some experiments are conducted on a sheared basal layer, to simulate regional extensional tectonics. Finally, injection of compressed air at the base of the model allows to simulate the effect of pore pressure and the behavior of low friction - low shear strength materials. Several sets of experiments are run to account for the role of each factor or combination of factors on the flank dynamics of the volcano. We use a high resolution laser scanner and control points on the surface of the models to trace surface deformation as a function of the imposed physical conditions. The experiments show that the asymmetric topography systematically enhances the deformation on the side with the highest topographic gradient (i.e. seaside), under inflating reservoirs and dike emplacements (up to 3-4 times), regional tectonics (up to 15%), crustal layering (up to 25%) and the effect of pore pressures. These results, compared with the known rates in nature, allow us to define the relative importance of the different factors on

  19. 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

  20. [Importance of the flank line in the radiologic semiotics of abdominal pathology].

    PubMed

    Minutoli, A; Gaeta, M; Mantineo, G; Bosurgi, G

    1986-04-01

    The authors have analysed the flank stripe in 70 normal subjects and in patients with abdominal disease. The flank stripe has a wide variability and is very useful to detect and locate abdominal pathologic conditions.

  1. The Prompt Design of CNC Grinder Based on Flexible Product Platform

    NASA Astrophysics Data System (ADS)

    Gan, Dequan; Jiang, Ping; Zhang, Huangao; Chen, Zishun

    In mass customization the product platform is the power method to improve the reused ability of existing design resource. But to the high degree modularity product, the module limits the commonality of product platform. The flexible product platform solves the conflict of modularity’s variety and commonality. The platform parameters denote the common properties of product platform and different values of those parameters realize the flexible of product platform. Then the parameter-independent modules can be combined into a physical product platform and extend to satisfy much more market segments. The flexible product platform of CNC grinder improves the reutilization and guides the designer promptly to develop the individual CNC grinder for personal customer needs.

  2. Research on efficient and stable milling using CNC small size tool

    NASA Astrophysics Data System (ADS)

    Luo, Yongxin; Zhao, Beichen; Long, Hua; Yu, Nanlin

    2011-05-01

    In order to mill efficiently and stably using small size tool on computer numerical control machine(CNC machine), the paper establishes dual-objective function on the basis of the minimum tool wear and the largest cutting efficiency. Meanwhile, the influence of diameter and length of tool suspended on stability is considered under the guidance of chatter stability analysis relationship. Research results show that, Pareto solution set which has two factors into account conflicting can be obtained by Genetic Algorithms, combined Pareto solution set with the frequency response function (FRF) chatter stability diagram, Pareto solutions of the smaller range of options, the milling parameters which meet the requirements of efficient and stable milling of CNC machine tools can be optimized conveniently and accurately. When the tool suspended length increases, the system stiffness decreases and the chatter stability domain graphic drops down, Stability region narrows.

  3. 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.

  4. The search for radio emission from the 55 Cnc exoplanetary system using LOFAR

    NASA Astrophysics Data System (ADS)

    Turner, Jake; Griessmeier, Jean-Mathias; Zarka, Philippe

    2016-10-01

    Detection of radio emission from exoplanets can provide information on the star-planet system that is very difficult or impossible to study otherwise, such as the planet's magnetic field, magnetosphere, rotation period, orbit inclination, and star-planet interactions. Such a detection in the radio would open up a whole new field in exoplanets, however, currently there are no confirmed detections of an exoplanet at radio frequencies. In this study, we search for non-thermal radio emission from 55 Cnc, an exoplanetary system with 5 planets. 55 Cnc is among the best targets for this search according to theoretical studies. We observed for 18 hours with the Low-Frequency Array (LOFAR) in the frequency range 26-73 MHz with full-polarization and covered the entire orbital phases of the innermost planet. During the observations four beams were recorded simultaneously on 55 Cnc, a patch of nearby "empty" sky, the nearby pulsar B0823+26, and a bright radio source in the field. The extra beams make this setup unique since they can be used for control of the telescope gain and to verify that a detection in the exoplanet beam is not a false-positive detection (e.g. ionospheric fluctuations). An automatic pipeline was created to automatically find Radio Frequency Interference (RFI) and to search for emission in the exoplanet beam. We will apply this observational technique and pipeline to more of the theoretically best candidates in the future.

  5. 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.

  6. Tsunami deposits related to Fogo flank failure (Cape Verde Islands)

    NASA Astrophysics Data System (ADS)

    Paris, Raphael; Chevalier, Joel; Lavigne, Franck

    2010-05-01

    Oceanic shield volcanoes are prone to massive flank failures involving dozens to hundreds of km³. Fogo active volcano (Cape Verde Islands) is nested in a large horseshoe shaped caldera opened to the east. This volcano-tectonic structure could be the result of past failures of the edifice (Day et al., 1999). Debris avalanche deposits were identified offshore (Masson et al., 2008). The volume of the last collapse (> 62 ka) ranges between 130 and 160 km³, making the hypothesis for a past giant tsunami highly probable. Santiago island is located 50 km east of Fogo island. The west coast of Santiago may have been severely affected by the tsunami. A field survey was carried out in March 2009. Surprisingly, tsunami deposits were found only in Tarrafal, where a large bay may have amplified the wave and provided sediments. Elsewhere, no evidences of tsunami were found. The tsunami deposits appear as marine conglomerate in discontinuity above a reddish to yellowish paleo-soil. Nice cross-sections were found along the coast, in the northern part of the Tarrafal Bay. The thickness apparently increases landward (up to 4 m). The deposits consist in stacked units of pebbles or boulders, with numerous marine bioclasts (shells, corals, coralline algae). The basal contact with the paleo-soil displays scour-and-fill features. These tsunami deposits are similar to those previously described by Pérez-Torrado et al. (2006) in the Canary Islands. References Day, S.J., Heleno da Silva, S.I.N., Fonseca, J.F.B.D., 1999. A past giant lateral collapse and present-day flank instability of Fogo, Cape Verde Islands. Journal of Volcanology and Geothermal Research 99, 191-218. Masson, D.G., Le Bas, T.P., Grevemeyer, I., Weinrebe, W., 2008. Flank collapse and large-scale landsliding in the Cape Verde Islands, off West Africa. Geochemistry, Geophysics, Geosystems 9 (7). Pérez Torrado, F.J., Paris, R., Cabrera, M.C., Schneider, J.L., Wassmer, P., Carracedo, J.C., Rodriguez Santana, A., Santana, F

  7. A modal-spectral model for flanking transmissions

    NASA Astrophysics Data System (ADS)

    Poblet-Puig, Jordi

    2016-11-01

    A model for the prediction of direct and indirect (flanking) sound transmissions is presented. It can be applied to geometries with extrusion symmetry. The structures are modelled with spectral finite elements. The acoustic domains are described by means of a modal expansion of the pressure field and must be cuboid-shaped. These reasonable simplifications in the geometry allow the use of more efficient numerical methods. Consequently the coupled vibroacoustic problem in structures such as junctions is efficiently solved. The vibration reduction index of T-junctions with acoustic excitation and with point force excitation is compared. The differences due to the excitation type obey quite general trends that could be taken into account by prediction formulas. However, they are smaller than other uncertainties not considered in practice. The model is also used to check if the sound transmissions of a fully vibroacoustic problem involving several flanking paths can be reproduced by superposition of independent paths. There exist some differences caused by the interaction between paths, which are more important at low frequencies.

  8. 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.

  9. 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

  10. 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

  11. The Behaviour of Uranium in a Ridge Flank Setting

    NASA Astrophysics Data System (ADS)

    Dunk, R. M.; Mills, R. A.; Jenkins, W. J.; Mottl, M. J.; Wheat, G.; Devey, C. W.

    2002-12-01

    The magnitude and locus of hydrothermal circulation remains one of the largest uncertainties in global geochemical budgets. In particular, a large and poorly constrained chemical flux may be associated with low temperature fluid flow through the mid-ocean ridge flanks. Uranium is potentially a valuable tracer of this low temperature hydrothermal exchange as removal of U during high temperature on-axis hydrothermal circulation is quantitative and appears to be virtually complete in warm spring fluids of 62-64°C. The exchange of U across a young thinly sedimented ridge flank has been examined along a transect across the eastern flank of the East Pacific Rise at 14°S. Sediment cores were collected and pore fluids extracted during the EXCOII cruise from locations overlying oceanic crust with estimated ages of 0.3, 1.5 and 4.0 Ma. Upwelling of basement fluids was observed in some cores collected from each site. A number of these cores reached basement, providing a good measure of sediment thickness and allowing the composition of basement fluids to be inferred. The maximum ΔT in the EXCO study area was ~2°C, thus these samples represent very low temperature hydrothermal fluids. Two distinct basement fluids were identified from pore fluid measurements. A reducing fluid with U concentrations indicating removal of ~60% seawater U, and a less altered fluid suggesting removal of ~10-20% seawater U. A large diagenetic signal, with significant release of U at ~150 cm depth, was observed in regions of no flow at the 0.3 Ma site. The systematic deviations of pore fluid U concentration from the background diagenetic profile have been used to estimate basement fluid upwelling velocities at this site in the range of a few mm to cm per year through the application of a simple advection-diffusion model. Incorporating these new data into a simple fluid flow model based on geophysical and geochemical budget constraints suggests that the hydrothermal U sink is on the order of ~10

  12. 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

  13. 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).

  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. Pore Pressure Distribution and Flank Instability in Hydrothermally Altered Stratovolcanoes

    NASA Astrophysics Data System (ADS)

    Ball, J. L.; Taron, J.; Hurwitz, S.; Reid, M. E.

    2015-12-01

    Field and geophysical investigations of stratovolcanoes with long-lived hydrothermal systems commonly reveal that initially permeable regions (such as brecciated layers of pyroclastic material) can become both altered and water-bearing. Hydrothermal alteration in these regions, including clay formation, can turn them into low-permeability barriers to fluid flow, which could increase pore fluid pressures resulting in flank slope instability. We examined elevated pore pressure conditions using numerical models of hydrothermal flow in stratovolcanoes, informed by geophysical data about internal structures and deposits. Idealized radially symmetric meshes were developed based on cross-sectional profiles and alteration/permeability structures of Cascade Range stratovolcanoes. We used the OpenGeoSys model to simulate variably saturated conditions in volcanoes heated only by regional heat fluxes, as well as 650°C intrusions at two km depth below the surface. Meteoric recharge was estimated from precipitation rates in the Cascade Range. Preliminary results indicate zones of elevated pore pressures form: 1) where slopes are underlain by continuous low-permeability altered layers, or 2) when the edifice has an altered core with saturated, less permeable limbs. The first scenario might control shallow collapses on the slopes above the altered layers. The second could promote deeper flank collapses that are initially limited to the summit and upper slopes, but could progress to the core of an edifice. In both scenarios, pore pressures can be further elevated by shallow intrusions, or evolve over longer time scales under forcing from regional heat flux. Geometries without confining low-permeability layers do not show these pressure effects. Our initial scenarios use radially symmetric models, but we are also simulating hydrothermal flow under real 3D geometries with asymmetric subsurface structures (Mount Adams). Simulation results will be used to inform 3D slope

  16. 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

  17. 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

  18. Line blanketed model atmospheres of Ap-stars. V - The Hg-Mn stars 53 Tau and Kappa CNC

    NASA Astrophysics Data System (ADS)

    Stepien, K.; Muthsam, H.

    1981-07-01

    All available observations of the energy distributions of 53 Tau and κ Cnc from the wavelength interval between Lα and the Paschen jump are compared with a series of model atmospheres in which temperature, microturbulent velocity and chemical composition were varied. Good agreement is obtained if effective temperatures of 53 Tau and κ Cnc are 11,250 K and 12,800 K, respectively, and the chemical compositions are taken from Strom (1969) and Kodaira (1965). New chemical compositions obtained by Heacox (1979) produce too much blanketing in UV, particularly for κ Cnc. For 53 Tau the set with υmicr = 0 gives equally good fit as the old abundances and the resulting temperature is 11,400 K. Observations of both stars show a slight excess of radiation in the red. It is suggested that this excess may be caused by the circumstellar matter.

  19. 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.

  20. 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.

  1. 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.

  2. Photometric solution and period analysis of the contact binary system AH Cnc

    NASA Astrophysics Data System (ADS)

    Peng, Ying-Jiang; Luo, Zhi-Quan; Zhang, Xiao-Bin; Deng, Li-Cai; Wang, Kun; Tian, Jian-Feng; Yan, Zheng-Zhou; Pan, Yang; Fang, Wei-Jing; Feng, Zhong-Wen; Tang, De-Lin; Liu, Qi-Li; Sun, Jin-Jiang; Zhou, Qiang

    2016-10-01

    Photometric observations of AH Cnc, a W UMa-type system in the open cluster M67, were carried out by using the 50BiN telescope. About 100 h of time-series B- and V -band data were taken, based on which eight new times of light minima were determined. By applying the Wilson-Devinney method, the light curves were modeled and a revised photometric solution of the binary system was derived. We confirmed that AH Cnc is a deep contact (f = 51%), low mass-ratio (q = 0.156) system. Adopting the distance modulus derived from study of the host cluster, we have re-calculated the physical parameters of the binary system, namely the masses and radii. The masses and radii of the two components were estimated to be respectively 1.188(±0.061) M ⊙, 1.332(±0.063) R ⊙ for the primary component and 0.185(±0.032) M ⊙, 0.592(±0.051) R ⊙ for the secondary. By adding the newly derived minimum timings to all the available data, the period variations of AH Cnc were studied. This shows that the orbital period of the binary is continuously increasing at a rate of dp/dt = 4.29 × 10‑10 d yr‑1. In addition to the long-term period increase, a cyclic variation with a period of 35.26 yr was determined, which could be attributed to an unresolved tertiary component of the system.

  3. 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

  4. 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.

  5. Performance Evaluation of Multi-Axis CNC Machine Tools by Interferometry Principle using Laser Calibration System

    NASA Astrophysics Data System (ADS)

    Barman, S.; Sen, R.

    2012-06-01

    Advancement in digital electronics and microprocessors has made the manufacturing sector capable to generate complex components within small tolerance zone in nanometre range at one machining center. All motion control systems have some form of position feed back system fitted with the machine. But the systems are not perfectly accurate due to the errors in the positioning performance of the machine tools which will change over time to time due to wear, damage and environmental effect. The complex structure of multi-axis CNC machine tools produces an inaccuracy at the tool tip caused by kinematic parameter deviations resulting in manufacturing errors, assembly error and quasi-static errors. Analysis of these errors using a laser measurement system provides the user with a way to achieve better accuracy, and hence higher quality output from these processes. In this paper, characteristic of the positioning errors of the axes of multi-axis CNC machine tools and the technique to measure the errors by a laser interferometer calibration system have been discussed and the positioning accuracy of the machine each axis has been verified.

  6. Non-contact automatic measurement of free-form surface profiles on CNC machines

    NASA Astrophysics Data System (ADS)

    Fan, Kuang-Chao; Wen, Kuang-Pu

    1993-09-01

    This paper describes the work to develop a non-contact type automatic measurement system for any free-form surfaces on a CNC machine tool or a coordinate measuring machine (CMM) and its CAD/CAM integration. A laser probe made by Keyence Co. model LC-2220 was integrated into the CNC machine as the non-contact sensor. A measurement software has been developed for automatic surface tracing of any free-form profile. Data transfer to any commercially available CAD/CAM system for reverse engineering is also available via proper DXF file. Extensive calibration work has been carried out on the systematic accuracy of the laser probe with respect to the color material surface slope and edge detection of the workpiece by the use of a HP5528 laser interferometer system. Having employed the surface painting technique the shape error of the copied object relative to its master piece was found within 30 micrometers which is deemed adequate enough to the mold industry.

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. CNC machine tool's wear diagnostic and prognostic by using dynamic Bayesian networks

    NASA Astrophysics Data System (ADS)

    Tobon-Mejia, D. A.; Medjaher, K.; Zerhouni, N.

    2012-04-01

    The failure of critical components in industrial systems may have negative consequences on the availability, the productivity, the security and the environment. To avoid such situations, the health condition of the physical system, and particularly of its critical components, can be constantly assessed by using the monitoring data to perform on-line system diagnostics and prognostics. The present paper is a contribution on the assessment of the health condition of a computer numerical control (CNC) tool machine and the estimation of its remaining useful life (RUL). The proposed method relies on two main phases: an off-line phase and an on-line phase. During the first phase, the raw data provided by the sensors are processed to extract reliable features. These latter are used as inputs of learning algorithms in order to generate the models that represent the wear's behavior of the cutting tool. Then, in the second phase, which is an assessment one, the constructed models are exploited to identify the tool's current health state, predict its RUL and the associated confidence bounds. The proposed method is applied on a benchmark of condition monitoring data gathered during several cuts of a CNC tool. Simulation results are obtained and discussed at the end of the paper.

  16. 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.

  17. 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.

  18. The study of double flank micro gear roll testing

    NASA Astrophysics Data System (ADS)

    Liu, Yen-Chih; An, Nai-Chun; Yang, Shu-Han; Yan, Sheng-Zhan; Chen, Shih-Lu

    2011-12-01

    The recent fast development of multifunctional portable electronic devices results in the obvious requirement of micro mechanical components. Due to the popular application of the micro actuators and the micro gearboxes, micro gears become the frequently used micro mechanical component in a small device such as small intelligent robots or dental surgical devices. Metal Industries Research & Development Centre (MIRDC) has successfully developed a small speed reducer that comprises several micro planetary gear trains. The module of this micro planetary gear train is 0.12mm. Since all gears are small, no commercial instrument is available for inspection. How to evaluate the manufacturing quality of micro gears becomes an important issue. This study focuses on the double flank gear rolling test and a specialized apparatus is built referring to the testing requirements in the international standards. The center distance variation during the rolling test is recorded and two indices, the total radial composite deviation and the maximum tooth-to-tooth radial composite deviation, are calculated to evaluate the accuracy grade of the micro gears. Experimental results show that the accuracy of the micro gear made by the cold forging process conforms to grade 7 defined in the ISO 1328-2 while grade 2 is achieved if the JGMA 116-02 is specified.

  19. Asymmetric nucleosomes flank promoters in the budding yeast genome.

    PubMed

    Ramachandran, Srinivas; Zentner, Gabriel E; Henikoff, Steven

    2015-03-01

    Nucleosomes in active chromatin are dynamic, but whether they have distinct structural conformations is unknown. To identify nucleosomes with alternative structures genome-wide, we used H4S47C-anchored cleavage mapping, which revealed that 5% of budding yeast (Saccharomyces cerevisiae) nucleosome positions have asymmetric histone-DNA interactions. These asymmetric interactions are enriched at nucleosome positions that flank promoters. Micrococcal nuclease (MNase) sequence-based profiles of asymmetric nucleosome positions revealed a corresponding asymmetry in MNase protection near the dyad axis, suggesting that the loss of DNA contacts around H4S47 is accompanied by protection of the DNA from MNase. Chromatin immunoprecipitation mapping of selected nucleosome remodelers indicated that asymmetric nucleosomes are bound by the RSC chromatin remodeling complex, which is required for maintaining nucleosomes at asymmetric positions. These results imply that the asymmetric nucleosome-RSC complex is a metastable intermediate representing partial unwrapping and protection of nucleosomal DNA on one side of the dyad axis during chromatin remodeling.

  20. 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

  1. 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…

  2. 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

  3. Automatic measurement of spur gear dimensions using laser light, part 2: measurement of flank profile

    NASA Astrophysics Data System (ADS)

    Younes, M. A.; Khalil, Abdallah M.; Damir, Mohamed

    2005-10-01

    In part I of this study a laser-based system for automatic measurement of spur gears' tooth thickness and pitch was introduced. The developed system provides an inaccuracy value on the order of 5 µm, and the measurement time, for all gear teeth, was just about 1 min. In this part the experimental work is further extended to measure the tooth flank profile of spur gears. Flank profile is one of the most important factors that affect gear performance. In gear meshing, motion is transferred through contact along gear flanks. Deviations in flank profile due to errors in manufacturing or nonuniform wear result in variations in gear movement. Measurement of the flank profile can help in adjusting the gear manufacturing process, control the quality of manufactured gears, and monitor the wear of gears during action. The proposed flank profile measurement system is based on the principle of optical triangulation. The flank profile measurement setup is integrated with that of the tooth thickness and pitch, and hence tooth thickness, pitch, and profile measurements are performed simultaneously, and the measurement time for the three parameters for all gear teeth remains less than 1 min. Software is developed to graph the actual tooth profile and evaluate its deviation from nominal shape. The flank profiles measured using the developed system are in good agreement with those obtained from a well-established measurement method.

  4. Optimization of process parameters in CNC turning of aluminium alloy using hybrid RSM cum TLBO approach

    NASA Astrophysics Data System (ADS)

    Rudrapati, R.; Sahoo, P.; Bandyopadhyay, A.

    2016-09-01

    The main aim of the present work is to analyse the significance of turning parameters on surface roughness in computer numerically controlled (CNC) turning operation while machining of aluminium alloy material. Spindle speed, feed rate and depth of cut have been considered as machining parameters. Experimental runs have been conducted as per Box-Behnken design method. After experimentation, surface roughness is measured by using stylus profile meter. Factor effects have been studied through analysis of variance. Mathematical modelling has been done by response surface methodology, to made relationships between the input parameters and output response. Finally, process optimization has been made by teaching learning based optimization (TLBO) algorithm. Predicted turning condition has been validated through confirmatory experiment.

  5. 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.

  6. 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

  7. 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).

  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. 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

  10. 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.

  11. 8. DETAIL OF ENTRANCE WITH FLANKING ROUND TOWERS TO A.O.H. ...

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

    8. DETAIL OF ENTRANCE WITH FLANKING ROUND TOWERS TO A.O.H. HALL, EAST SIDE - Anaconda Historic District, Ancient Order of Hibernians Hall, 321-323 East Commercial Street, Anaconda, Deer Lodge County, MT

  12. 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

  13. Flank mass and pain in a 72-year-old man.

    PubMed

    Brady, M B; Ewing, R H; Robinson, A E; Dowling, E A

    1986-05-01

    This patient had retroperitoneal multiseptated masses, which extensively invaded the right flank and thigh musculature. The radiologic, pathologic, and clinical findings were consistent with a retroperitoneal pseudomyxoma from an appendiceal mucocele.

  14. Flank bulge following supracostal percutaneous nephrolithotomy: A report of 2 cases

    PubMed Central

    Lantz, Andrea G.; Pace, Kenneth T.; Honey, R. John D’A.

    2013-01-01

    Damage to intercostal nerves during surgical procedures has been associated with a postoperative flank bulge, due to denervation of the anterolateral abdominal wall musculature. This complication has not been reported following percutaneous nephrolithotomy (PCNL). We are aware of 3 cases, but have details on 2 cases of postoperative flank bulge following supracostal PCNL which are reported here. We also suggest how this complication could potentially be minimized. PMID:24032069

  15. Ultrasound Detection of a Renal Mass in a Patient with Flank Pain and Hematuria

    PubMed Central

    Marzec, Karl; Mailhot, Thomas; Perera, Phillips

    2013-01-01

    Flank pain with hematuria is a common chief complaint in the emergency department (ED). Patients are often diagnosed with renal calculi or pyelonephritis and discharged with analgesics or antibiotics and follow-up. This case study describes a patient who presented to the ED with a 1 week history of flank pain and hematuria and was subsequently found to have a large renal mass on bedside ultrasound. PMID:23599845

  16. Effect of flanking bases on quadruplex stability and Watson-Crick duplex competition.

    PubMed

    Arora, Amit; Nair, Divya R; Maiti, Souvik

    2009-07-01

    Guanine-rich DNA sequences have the ability to fold into four-stranded structures called G-quadruplexes, and are considered as promising anticancer targets. Although the G-quadruplex structure is composed of quartets and interspersed loops, in the genome it is also flanked on each side by numerous bases. The effect of loop length and composition on quadruplex conformation and stability has been well investigated in the past, but the effect of flanking bases on quadruplex stability and Watson-Crick duplex competition has not been addressed. We have studied in detail the effect of flanking bases on quadruplex stability and on duplex formation by the G-quadruplex in the presence of complementary strands using the quadruplex-forming sequence located in the promoter region of the c-kit oncogene. The results obtained from CD, thermal difference spectrum and UV melting demonstrated the effect of flanking bases on quadruplex structure and stability. With the increase in flank length, the increase in the more favorable DeltaH(vH) is accompanied by a striking increase in the unfavorable DeltaS(vH), which resulted in a decrease in the overall DeltaG(vH) of quadruplex formation. Furthermore, CD, fluorescence and isothermal titration calorimetry studies demonstrated that the propensity to attain quadruplex structure decreases with increasing flank length.

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

    ScienceCinema

    None

    2016-07-12

    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

  18. Planetpol polarimetry of the exoplanet systems 55Cnc and τBoo

    NASA Astrophysics Data System (ADS)

    Lucas, P. W.; Hough, J. H.; Bailey, J. A.; Tamura, M.; Hirst, E.; Harrison, D.

    2009-02-01

    We present very sensitive polarimetry of 55Cnc and τBoo in an attempt to detect the partially polarized reflected light from the planets orbiting these two stars. 55Cnc is orbited by a hot Neptune planet (55Cnce) at 0.038au, a hot Jupiter planet (55Cncb) at 0.11au and at least three more distant planets. The polarization of this system is very stable, showing no sign of the periodic variations that would be expected if a short-period planet were detected. The measured standard deviation of the nightly averaged Stokes Q/I and U/I parameters is 2.2 × 10-6. We derive upper limits on the geometric albedo, AG, and planetary radius using Monte Carlo multiple scattering simulations of a simple model atmosphere. We assume Rayleigh-like scattering and polarization behaviour (scaled by the maximum polarization, pm, at 90°) and pressure insensitive extinction. Atmospheres in which multiple scattering plays only a small role have an almost linear relation between polarization and AG. In this case, the 4σ upper limit is AG < 0.13(R/1.2RJup)-2p-1m for 55Cnce. This is most easily explained if 55Cnce is relatively small, like GJ436b, and therefore not a pure H-He planet. The data do not provide a useful upper limit for 55Cncb. τBoo is orbited by an unusually massive hot Jupiter planet. The data show a standard deviation in the night-to-night average Stokes Q/I and U/I polarization parameters of 5.1 × 10-6. The 4σ upper limit is AG < 0.37(R/1.2RJup)-2p-1m for τBoob, adopting the fairly well established orbital inclination i ~ 40°. This extends the similar upper limits reported previously for this planet to longer wavelengths. The fact that the τBoo data show more scatter, despite the smaller photon noise for this bright star, may be due to the spot activity detected photometrically by the Microvariability & Oscillations of Stars (MOST) satellite. These results contrast markedly with the recent claim of a 3σ detection of a periodic polarization signal from HD189733 with

  19. Dissecting the influence of the collinear and flanking bars in White's effect.

    PubMed

    Blakeslee, Barbara; Padmanabhan, Ganesh; McCourt, Mark E

    2016-10-01

    In White's effect equiluminant test patches placed on the black and white bars of a square-wave grating appear different in brightness. The illusion has generated intense interest because the direction of the brightness effect does not correlate with the amount of black or white border in contact with the test patch, or in its general vicinity. Therefore, unlike brightness induction effects such as simultaneous contrast, White's effect is not consistent with explanations based on contrast or assimilation that depend solely on the relative amounts of black and white surrounding the test patches. We independently manipulated the luminance of the collinear and flanking bars to investigate their influence on test patch matching luminance (brightness). The inducing grating was a 0.5c/d square-wave and test patches measured 1.0° in width and either 0.5° or 3.0° in height. Test patches measuring 0.5° in height had more extensive contact with the collinear bars and test patches measuring 3.0° in height had more extensive contact with the flanking bars. The luminance of the collinear (or flanking) bars assumed twenty values from 3.2 to 124.8cd/m(2), while the luminance of the flanking (or collinear) bars remained white (124.8cd/m(2)) or black (3.2cd/m(2)). Under these conditions the influence of the collinear and flanking bars was found to be purely in the direction of contrast. The effect was dominated by contrast from the collinear bars (which results in White's effect), however, the influence of the flanking bars was also in the contrast direction. The data elucidate the luminance relationships between the collinear and flanking bars which produce the behavior associated with White's effect as well as that associated with "the inverted White effect" which is akin to simultaneous contrast.

  20. 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.

  1. On the Central Symmetry of the Circumstellar Envelope of RS Cnc

    NASA Astrophysics Data System (ADS)

    Nhung, P. T.; Hoai, D. T.; Winters, J. M.; Darriulat, P.; Gérard, E.; Le Bertre, T.

    2015-08-01

    We present a phenomenological study of CO (1-0) and CO (2-1) emission from the circumstellar envelope (CSE) of the AGB star RS Cnc. It reveals departures from central symmetry that turn out to provide a new tool for the exploration of some of the CSE properties. We use a wind model including a bipolar flow with a typical wind velocity of ˜8 km s-1, decreasing to ˜2 km s-1 near the equator, to describe Doppler velocity spectral maps obtained by merging data collected at the IRAM Plateau de Bure Interferometer and the Pico Veleta single-dish radio telescope. Parameters describing the wind morphology and kinematics are obtained, together with the radial dependence of the gas temperature in the domain of the CSE probed by the CO observations. Significant north-south central asymmetries are revealed by the analysis, which we quantify using a simple phenomenological description. The origin of such asymmetries is unclear for the moment.

  2. On the central symmetry of the circumstellar envelope of RS Cnc

    NASA Astrophysics Data System (ADS)

    Tuyet Nhung, Pham; Thi Hoai, Do; Winters, Jan Martin; Darriulat, Pierre; Gérard, Eric; Le Bertre, Thibaut

    2015-05-01

    We present a phenomenological study of CO(1-0) and CO(2-1) emission from the circumstellar envelope (CSE) of the Asymptotic Giant Branch (AGB) star RS Cnc. It reveals departures from central symmetry that turn out to be efficient tools for the exploration of some of the properties of the CSE. We use a wind model including a bipolar flow with a typical wind velocity of ~8 km s-1 that decreases to ~2 km s-1 near the equator. This wind model is used to describe Doppler velocity spectral maps obtained by merging data collected at the IRAM Plateau de Bure Interferometer and Pico Veleta single dish radio telescope. Parameters describing the wind morphology and kinematics are obtained, together with the radial dependence of the gas temperature in the domain of the CSE probed by the CO observations. Significant north-south central asymmetries are revealed by the analysis, which we quantify using a simple phenomenological description. The origin of such asymmetries is unclear. Based on observations carried out with the IRAM Plateau de Bure Interferometer and the IRAM 30 m telescope. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain).

  3. 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

  4. An adaptive recurrent-neural-network motion controller for X-Y table in CNC machine.

    PubMed

    Lin, Faa-Jeng; Shieh, Hsin-Jang; Shieh, Po-Huang; Shen, Po-Hung

    2006-04-01

    In this paper, an adaptive recurrent-neural-network (ARNN) motion control system for a biaxial motion mechanism driven by two field-oriented control permanent magnet synchronous motors (PMSMs) in the computer numerical control (CNC) machine is proposed. In the proposed ARNN control system, a RNN with accurate approximation capability is employed to approximate an unknown dynamic function, and the adaptive learning algorithms that can learn the parameters of the RNN on line are derived using Lyapunov stability theorem. Moreover, a robust controller is proposed to confront the uncertainties including approximation error, optimal parameter vectors, higher-order terms in Taylor series, external disturbances, cross-coupled interference and friction torque of the system. To relax the requirement for the value of lumped uncertainty in the robust controller, an adaptive lumped uncertainty estimation law is investigated. Using the proposed control, the position tracking performance is substantially improved and the robustness to uncertainties including cross-coupled interference and friction torque can be obtained as well. Finally, some experimental results of the tracking of various reference contours demonstrate the validity of the proposed design for practical applications. PMID:16602590

  5. 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.

  6. Commissioning of the first Precessions 1.2-m CNC polishing machines for large optics

    NASA Astrophysics Data System (ADS)

    Walker, D. D.; Beaucamp, A. T. H.; Doubrovski, V.; Dunn, C.; Evans, R.; Freeman, R.; McCavana, G.; Morton, R.; Riley, D.; Simms, J.; Yu, G.; Wei, X.

    2006-08-01

    This paper reports on the commissioning of the first of Zeeko's "IRP1200" 1.2m capacity 7-axis automated CNC polishing machines. These combo machines now support five different removal regimes, which are described. The machines differ substantially from Zeeko's more familiar 200mm machines on which we have focused before, in terms of overall architecture and detailed design. Large and small optics place different demands on part-fixturing, tooling, machine speeds and accelerations, metrology, slurry-handling, part-loading and access etc. These have had a profound effect on the development-path from 200 to 1.2m machines. Moreover, an advance in the kinematic design has extended the allowable range of surface slope-angles from typically 30° up to a hemisphere. The paper presents results from the pass-off trials, the first fluid-jet experiment, and the development of tooling to address a requirement to smooth a part with a local defect.

  7. 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

  8. Ruthenium(II) Complexes Containing Lutidine-Derived Pincer CNC Ligands: Synthesis, Structure, and Catalytic Hydrogenation of C-N bonds.

    PubMed

    Hernández-Juárez, Martín; López-Serrano, Joaquín; Lara, Patricia; Morales-Cerón, Judith P; Vaquero, Mónica; Álvarez, Eleuterio; Salazar, Verónica; Suárez, Andrés

    2015-05-11

    A series of Ru complexes containing lutidine-derived pincer CNC ligands have been prepared by transmetalation with the corresponding silver-carbene derivatives. Characterization of these derivatives shows both mer and fac coordination of the CNC ligands depending on the wingtips of the N-heterocyclic carbene fragments. In the presence of tBuOK, the Ru-CNC complexes are active in the hydrogenation of a series of imines. In addition, these complexes catalyze the reversible hydrogenation of phenantridine. Detailed NMR spectroscopic studies have shown the capability of the CNC ligand to be deprotonated and get involved in ligand-assisted activation of dihydrogen. More interestingly, upon deprotonation, the Ru-CNC complex 5 e(BF4 ) is able to add aldimines to the metal-ligand framework to yield an amido complex. Finally, investigation of the mechanism of the hydrogenation of imines has been carried out by means of DFT calculations. The calculated mechanism involves outer-sphere stepwise hydrogen transfer to the C-N bond assisted either by the pincer ligand or a second coordinated H2 molecule.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Further application and amelioration of a novel CNC aspheric grinding machine

    NASA Astrophysics Data System (ADS)

    Hu, Jianjun; Pan, Junhua

    2006-02-01

    Aspheric surface can be thought as being enveloped by a series of spherical surfaces with their centre on the same axis but having different positions. These spherical surfaces are tangent with the aspheric surface. A Φ600 CNC aspheric grinding machine with this novel operating principleis manufactured. The machine was reported in August 2005. We choose δ p, ɛ and α p as the key parameters of our grinding machine. δ p is the distance between the cup shaped tool's bottom and the vertex of the aspheric surface. α p is the rotational angle of the cup shaped tool. ɛ is the space angle of the cup shaped tool during the fabrication process of convex aspheric surface. This grinding machine can be used to fabricate a conic concave aspheric surface continuously about three hours. But we need change the cup shaped tool one time when we fabricate a conic convex aspheric surface in also about three hours. The grinding machine can also be used to fabricate high-order aspheric surface. In the last report we intoroduced that we used this machined fabricating a RC telescope system's primary and the secondary mirror. The PV-value is less than 5μm for the primary Φ350 concave hyperbolic aspheric surface which departure is about 55μm. The residual errors can be removed easily. This machine have been improved both the cup shaped tool and filter system. Using this grinding machine we have fabricated another Φ460 concave aspheric surface during the last month. The PV-values of these two mirrors are both less than 7μm. The aspheric grinding machine can be fitted for fabricating concave conicoids.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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…

  19. 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

  20. 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.

  1. 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.

  2. Cloning flanking sequence by single-primer PCR in transgenic plants.

    PubMed

    Ma, J; Wang, Y P; Ren, S; Zhang, Z; Lu, S; Wang, P W

    2014-10-20

    The insertion position of exogenous genes in plant genomes is usually identified by adapter ligation-mediated polymerase chain reaction (PCR), thermal asymmetric interlaced PCR, and restriction site extension PCR in transgenic plant research. However, these methods have various limitations, such as the complexity of designing primers and time-consuming and multiple-step procedures. The goal of this study was to establish an easier, more rapid, and more accurate method to clone flanking sequence using single-primer PCR in transgenic plants. Unknown flanking genome sequences in transgenic plants, including those in tobacco, soybean, rice, and maize, were cloned using the single-primer PCR method established in this study, with the Bar gene as the anchor gene. The primer 1 (P1), P2, and P3 PCRs obtained 4 sequences, and the completely correct flanking sequence of 508 bp that was obtained in the P3 PCR was verified by sequencing analysis. The single-primer PCR is more rapid and accurate than conventional methods, justifying its application widely in cloning flanking sequences in transgenic plants.

  3. 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

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

    USGS Publications Warehouse

    Lipman, Peter W.; Sisson, Thomas W.; Coombs, Michelle L.; Calvert, Andrew T.; Kimura, Jun-Ichi

    2006-01-01

    Present-day Kilauea is the more dynamic edifice, but prior to inception of Kilauea and during its early growth, Mauna Loa is inferred to have undergone intense volcano spreading, involving the Kaoiki–Honuapo fault system (considered a geometric analog of the Hilina system on Kilauea). Cumulative deformation of Mauna Loa's south flank during growth of Kilauea since 200–300 ka is estimated to have involved > 10 km of seaward spreading, displacing the rift zones of Kīlauea while its deep plumbing system and summit magma reservoir remained nearly fixed in space. Kilauea's rift zones, rather than migrating southward with time solely due to dike emplacement preferentially on the mobile seaward side, alternatively are interpreted to have been transported passively southward, “piggyback” style, during shield-stage growth of Kilauea as a blister on the still-mobile south flank of Mauna Loa. Such an evolution of Kilauea accounts for the arcuate geometry of the present-day rift zones, proximity of the summit magma supply to the exposed flank of Mauna Loa, initial submarine growth of the ancestral edifice, and present-day location of Mauna Loa rocks at shallow depth beneath the south flank of Kilauea.

  5. 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

  6. 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

  7. 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

  8. 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.

  9. 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

  10. 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.

  11. [A case of giant hemorrhagic adrenal pseudocystectomy with a flank incision].

    PubMed

    Takeuchi, Yasuharu; Ozaki, Yumi; Suyama, Taisuke; Sawada, Yoshitomo; Kuroda, Kanami; Nakajima, Kouichi; Oharaseki, Toshiaki; Wakayama, Megumi

    2011-06-01

    The patient was a 43-year-old woman who underwent detailed examinations for a retroperitoneal cystic lesion that was incidentally found during orthopedic treatment. Although the tumor was a non-functioning tumor, and diagnostic imaging was negative for malignancy, the tumor was surgically resected with a flank incision. The histopathological diagnosis was adrenal pseudocyst.

  12. 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.

  13. 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

  14. Analogue modelling of flank dynamics at Mount Etna, Italy: first results

    NASA Astrophysics Data System (ADS)

    Norini, G.; Acocella, V.; Neri, M.

    2009-04-01

    Mount Etna shows one of the most relevant case of active flank dynamics along its East and South-East sectors, with some well-known tectonic structures, such as the Pernicana fault, and evident morphologies, such as the Valle del Bove depression. Factors governing this flank dynamics are still matter of debate. Among these, the most important recognized by previous Authors are the topography, intrusion of a plutonic complex in the basement, rising of magma in the volcanic edifice, regional tectonics, low cohesion layers in the volcano basement, and pore pressure. In this study, a first set of analogue models of the complex flank dynamics of Mount Etna was conducted, and the experiments were analyzed for deformation characteristics. Several experiments were run to account for the role of each factor or combination of factors on the flank dynamics of the volcano. The modeling apparatus consisted of a sand cone on a sand base simulating the volcanic edifice and its basement. Sand used for the experiments was a mixture of high cohesion crushed silica sand and low cohesion glass microspheres. Alternated layers with different cohesion were used to account for the crustal structure of the basement. Geometry of the experiments was designated to simulate the topographic gradient at the eastern base of the volcano. Injections of high viscosity silly putty and low viscosity vegetable oil were used to model respectively the growth of an intrusive complex below the volcano and the rising of magma inside the deformed volcanic edifice. Some experiments were conducted on a sheared basal layer to reproduce the effect of the regional tectonics on the volcano flank dynamics. Finally, injection of compressed air in the model allows to simulate the pore pressure and its capability to reduce shear strength of the analogue granular materials. We used a high resolution laser scanner to trace surface deformation as function of the physical conditions of the models. The three

  15. Role of olivine cumulates in destabilizing the flanks of Hawaiian volcanoes

    USGS Publications Warehouse

    Clague, D.A.; Denlinger, R.P.

    1994-01-01

    The south flank of Kilauea Volcano is unstable and has the structure of a huge landslide; it is one of at least 17 enormous catastrophic landslides shed from the Hawaiian Islands. Mechanisms previously proposed for movement of the south flank invoke slip of the volcanic pile over seafloor sediments. Slip on a low friction de??collement alone cannot explain why the thickest and widest sector of the flank moves more rapidly than the rest, or why this section contains a 300 km3 aseismic volume above the seismically defined de??collement. It is proposed that this aseismic volume, adjacent to the caldera in the direction of flank slip, consists of olivine cumulates that creep outward, pushing the south flank seawards. Average primary Kilauea tholeiitic magma contains about 16.5 wt.% MgO compared with an average 10 wt.% MgO for erupted subaerial and submarine basalts. This difference requires fractionation of 17 wt.% (14 vol.%) olivine phenocrysts that accumulate near the base of the magma reservoir where they form cumulates. Submarine-erupted Kilauea lavas contain abundant deformed olivine xenocrysts derived from these cumulates. Deformed dunite formed during the tholeiitic shield stage is also erupted as xenoliths in subsequent alkalic lavas. The deformation structures in olivine xenocrysts suggest that the cumulus olivine was densely packed, probably with as little as 5-10 vol.% intercumulus liquid, before entrainment of the xenocrysts. The olivine cumulates were at magmatic temperatures (>1100??C) when the xenocrysts were entrained. Olivine at 1100??C has a rheology similar to ice, and the olivine cumulates should flow down and away from the summit of the volcano. Flow of the olivine cumulates places constant pressure on the unbuttressed seaward flank, leading to an extensional region that localizes deep intrusions behind the flank; these intrusions add to the seaward push. This mechanism ties the source of gravitational instability to the caldera complex and deep

  16. Radiometric Dating of Large Volume Flank Collapses in The Lesser Antilles Arc.

    NASA Astrophysics Data System (ADS)

    Quidelleur, X.; Samper, A.; Boudon, G.; Le Friant, A.; Komorowski, J.

    2004-12-01

    It is now admitted that flank collapses, probably triggered by magmatic inflation and/or gravitational collapses, is a recurrent process of the evolution of the Lesser Antilles Arc volcanoes. Large magnitude debris avalanche deposits have been identified offshore, in the Grenada basin (Deplus et al., 2001; Le Friant et al., 2001). The widest extensions have been observed off the coast of Dominica and St Lucia, with associated volumes up to 20 km3. Another large-scale event, with marine evidences probably covered by sediments and latter flank collapses, has been inferred onland from morphological evidences and characteristic deposits of the Carbets structure in Martinique. We present radiometric dating of these three major events using the K-Ar Cassignol-Gillot technique performed on selected groundmass. Both volcanic formations preceding flank collapses (remnants of the horseshoe shaped structures or basal lava flows) and following landslides (lava domes) have been dated. In the Qualibou depression of St. Lucia, the former structure has been dated at 1096+-16 ka and the collapse constrained by dome emplacement prior to 97+-2 ka (Petit Piton). In Dominica, several structures have been associated with repetitive flank collapse events inferred from marine data (Le Friant et al., 2002). The Plat-Pays event probably occurred after 96+-2 ka. Inside the inherited depression, Scotts Head, which is interpreted as a proximal pluri-kilometric megabloc from the Soufriere avalanche, has been dated at 14+-1 ka, providing an older bound for this event. In Martinique Island, three different domes within the Carbets structure have been dated at 335+-5 ka. Assuming a rapid magma emplacement following pressure release due to deloading, this constrains the age of this high magnitude event. Finally, these results obtained from three of the most voluminous flank collapses provide constraints to estimate the recurrence of these events, which represent one of the major hazards associated

  17. Submarine geology of Hana Ridge and Haleakala Volcano's northeast flank, Maui

    USGS Publications Warehouse

    Eakins, Barry W.; Robinson, Joel E.

    2006-01-01

    We present a morphostructural analysis of the submarine portions of Haleakala Volcano and environs, based upon a 4-year program of geophysical surveys and submersible explorations of the underwater flanks of Hawaiian volcanoes that was conducted by numerous academic and governmental research organizations in Japan and the U.S. and funded primarily by the Japan Agency for Marine–Earth Science and Technology. A resulting reconnaissance geologic map features the 135-km-long Hana Ridge, the 3000 km2 Hana slump on the volcano's northeast flank, and island-surrounding terraces that are the submerged parts of volcanic shields. Hana Ridge below 2000 m water depth exhibits the lobate morphology typical of the subaqueously erupted parts of Hawaiian rift zones, with some important distinctions: namely, subparallel crestlines, which we propose result from the down-rift migration of offsets in the dike intrusion zone, and an amphitheater at its distal toe, where a submarine landslide has embayed the ridge tip. Deformation of Haleakala's northeast flank is limited to that part identified as the Hana slump, which lies downslope from the volcano's submerged shield, indicating that flank mobility is also limited in plan, inconsistent with hypothesized volcanic spreading driven by rift-zone dilation. The leading edge of the slump has transverse basins and ridges that resemble the thrust ramps of accretionary prisms, and we present a model to describe the slump's development that emphasizes the role of coastally generated fragmental basalt on gravitational instability of Haleakala's northeast flank and that may be broadly applicable to other ocean-island slumps.

  18. 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.

  19. 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

  20. 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

  1. Dynamics of the eastern flank of Mt. Etna volcano (Italy) investigated by a dense GPS network

    NASA Astrophysics Data System (ADS)

    Bonforte, Alessandro; Puglisi, Giuseppe

    2006-05-01

    Mount Etna has developed at the intersection of two regional tectonic lineaments, the NNW-SSE trending Hybleo-Maltese escarpment, which separates the thick inland continental crust of the African platform from the Ionian Mesozoic oceanic crust, and the NE-SW Messina-Fiumefreddo fault that marks a rift zone between south Calabria and north-eastern Sicily, extending as far as the Mt. Etna area. All tectonic features affect, with outstanding surface features, the eastern side of the volcano. The eastern flank of the volcano is affected by a long-term motion toward ESE. In 1997, in order to increase the detail of the ground deformation pattern on the lower eastern flank of Mt. Etna, a new GPS network, the "Ionica" network, was installed on this sector of the volcano. This GPS network consists of 24 stations and covers the lower eastern flank of the volcano from the town of Catania to Taormina and from the coastline up to an altitude of about 1300 m. All the new stations consist in self-centring benchmarks; this kind of benchmark allows all station set-up errors to be avoided. Before the merging of the Ionica network to the frame of the global GPS network of Mt. Etna (in June 2001), three surveys were carried out on this network: in September 1997, August 1998 and January 2001. From the ground deformation pattern, it is possible to distinguish two different sectors, showing different characteristics of deformation. The southern part of the network shows a more uniform distribution of the vertical motion with a mean SE-ward horizontal component while the northern one shows an heterogeneous vertical motion with a ESE-ward horizontal component. Furthermore, a higher velocity is detected between 1997 and 1998, due to the additional stress induced by a shallow intrusion on the NW flank of the volcano. The model resulting from data inversions defines a wide sliding plane beneath the entire eastern flank of the volcano with a low dip angle. The expected velocity vectors fit

  2. 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

  3. 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

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

    NASA Astrophysics Data System (ADS)

    Lipman, Peter W.; Sisson, Thomas W.; Coombs, Michelle L.; Calvert, Andrew; Kimura, Jun-Ichi

    2006-03-01

    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 km 3) than previous estimates (15-40,000 km 3); lava-thickness accumulation rates appear to have remained nearly constant during edifice growth, as effusion rates increased from ˜25 × 10 6 m 3/yr at end of the alkalic stage to the present-day tholeiite rate of ˜100 × 10 6 m 3/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

  5. Piggyback Tectonics: Long-Term Growth of Kilauea on the South Flank of Mauna Loa

    NASA Astrophysics Data System (ADS)

    Lipman, P. W.; Sisson, T. W.; Coombs, M.; Lanphere, M.

    2002-12-01

    New 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 ancestral 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 the edifice remained below sea level, were probably first erupted at about 200 ka. Breccias from Papa'u Seamount, long interpreted as a landslide mass from the south flank of Kilauea, instead are fragments derived from subaerial Mauna Loa, requiring that the flank of a large Mauna Loa edifice underlies western parts of Kilauea at shallow depth. Seismic and gravity data show that the deep plumbing system for Kilauea's magma supply extends through the oceanic crust to depths of at least 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 are difficult to reconcile with a submarine origin for early Kilauea alkalic lavas, unless geometric relations between the two volcanoes changed substantially during growth of the Kilauea shield since its inception at about 200 ka. Seismic and ground deformation data suggest seaward spreading of the entire south flank of Hawaii Island, independently of the boundary between Kilauea and Mauna Loa, along a landward-dipping detachment fault system largely following the basal contact of the composite volcanic edifices with underlying sea-floor sediments. Current steady-state horizontal displacements increase progressively seaward, at rates of ~1.5 cm/yr on the lower flank of Mauna Loa and reaching 5-8 cm/yr at the Kilauea coastline

  6. 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

  7. Legionella pneumonia presenting with bilateral flank pain, hyponatraemia and acute renal failure

    PubMed Central

    Birkin, Celia; Biyani, Chandra Shekhar; Browning, Anthony J.

    2011-01-01

    Legionnaires’ disease (LD) is an often overlooked but a possible cause of sporadic community acquired pneumonia. High fever, cough and gastrointestinal symptoms are non-specific symptoms. Hyponatremia is more common in LD than pneumonia linked with other causes. A definitive diagnosis is usually confirmed by culture, urinary antigen testing for Legionella species. Macolide or quinolone antibiotic is the treatment of choice. We describe a case of Legionella pneumonia presenting with high fever, bilateral flank pain and oliguria. It is important for clinicians to be aware of this diagnosis when managing patients with flank pain. The case highlights the problems in differentiating LD from renal colic and the importance of proper history, physical examination with laboratory tests for appropriate management. PMID:22154178

  8. 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

    2016-09-01

    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.

  9. 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.

  10. Sequence tagged microsatellite profiling (STMP): improved isolation of DNA sequence flanking target SSRs

    PubMed Central

    Hayden, M. J.; Good, G.; Sharp, P. J.

    2002-01-01

    Sequence tagged microsatellite profiling (STMP) enables the rapid development of large numbers of co-dominant DNA markers, known as sequence tagged microsatellites (STMs). Each STM is amplified by PCR using a single primer specific to the conserved DNA sequence flanking the microsatellite repeat in combination with a universal primer that anchors to the 5′-ends of the microsatellites. It is also possible to convert STMs into conventional microsatellite, or simple sequence repeat (SSR), markers that are amplified using a pair of primers flanking the repeat sequence. Here, we describe a modification of the STMP procedure to significantly improve the capacity to convert STMs into conventional SSRs and, therefore, facilitate the development of highly specific DNA markers for purposes such as marker-assisted breeding. The usefulness of this technique was demonstrated in bread wheat. PMID:12466561

  11. Sequence tagged microsatellite profiling (STMP): improved isolation of DNA sequence flanking target SSRs.

    PubMed

    Hayden, M J; Good, G; Sharp, P J

    2002-12-01

    Sequence tagged microsatellite profiling (STMP) enables the rapid development of large numbers of co-dominant DNA markers, known as sequence tagged microsatellites (STMs). Each STM is amplified by PCR using a single primer specific to the conserved DNA sequence flanking the microsatellite repeat in combination with a universal primer that anchors to the 5'-ends of the microsatellites. It is also possible to convert STMs into conventional microsatellite, or simple sequence repeat (SSR), markers that are amplified using a pair of primers flanking the repeat sequence. Here, we describe a modification of the STMP procedure to significantly improve the capacity to convert STMs into conventional SSRs and, therefore, facilitate the development of highly specific DNA markers for purposes such as marker-assisted breeding. The usefulness of this technique was demonstrated in bread wheat. PMID:12466561

  12. Evidence for microbial carbon and sulfur cycling in deeply buried ridge flank basalt.

    PubMed

    Lever, Mark A; Rouxel, Olivier; Alt, Jeffrey C; Shimizu, Nobumichi; Ono, Shuhei; Coggon, Rosalind M; Shanks, Wayne C; Lapham, Laura; Elvert, Marcus; Prieto-Mollar, Xavier; Hinrichs, Kai-Uwe; Inagaki, Fumio; Teske, Andreas

    2013-03-15

    Sediment-covered basalt on the flanks of mid-ocean ridges constitutes most of Earth's oceanic crust, but the composition and metabolic function of its microbial ecosystem are largely unknown. By drilling into 3.5-million-year-old subseafloor basalt, we demonstrated the presence of methane- and sulfur-cycling microbes on the eastern flank of the Juan de Fuca Ridge. Depth horizons with functional genes indicative of methane-cycling and sulfate-reducing microorganisms are enriched in solid-phase sulfur and total organic carbon, host δ(13)C- and δ(34)S-isotopic values with a biological imprint, and show clear signs of microbial activity when incubated in the laboratory. Downcore changes in carbon and sulfur cycling show discrete geochemical intervals with chemoautotrophic δ(13)C signatures locally attenuated by heterotrophic metabolism.

  13. BPTs: thiophene-flanked benzodipyrrolidone conjugated polymers for ambipolar organic transistors.

    PubMed

    Rumer, Joseph W; Levick, Matthew; Dai, Sheng-Yao; Rossbauer, Stephan; Huang, Zhenggang; Biniek, Laure; Anthopoulos, Thomas D; Durrant, James R; Procter, David J; McCulloch, Iain

    2013-05-18

    A series of novel thiophene-flanked benzodipyrrolidone (BPT)-based alternating copolymers are synthesised, their optical and electrical properties evaluated. The BPT unit promotes a conjugated, planar polymer backbone, with a low bandgap, primarily due to low lying LUMO energy levels. Copolymerisation with thiophene exhibits well balanced ambipolar organic field-effect transistor performance, with electron and hole mobilities 0.1 and 0.2 cm(2) V(-1) s(-1), respectively.

  14. 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.

  15. 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

  16. Effect of carbamates on mRNA encoding lipid enzymes in hamster flank organs.

    PubMed

    López-Lezama, Juan C; Cabeza, Marisa; Mayorga, Israel; Soriano, Juan; Sainz, Teresita; Bratoeff, Eugene

    2014-05-01

    Flank organs are an androgen-dependent pilosebaceous complex present in male and female hamsters. These organs have been used for the evaluation of antiandrogenic drugs, which could be used for the treatment of androgen-dependent afflictions. This study demonstrated the role of four different steroidal carbamates 7-10 in the expression of mRNAs coding for different enzymes involved in the lipid metabolism in flank organs. To determine the biological effects of compounds 7-10 on the expression of mRNA coding for lipid enzymes, steroids 7-10, testosterone (T), progesterone (P), and/or 7-10 were applied on the flank organs. Later, the mRNA expression for the enzymes was determined by polymerase chain reaction. The binding of 8 and 9 to the progesterone receptor (PR) as well as their effects on the activity of 5α-reductase were also evaluated. Treatments with T, P, and 7-10 increased the mRNA expression for glycerol 3-phosphate acyl transferase (GPAT), β-hydroxy-β-methylglutaryl-CoA synthase (HMG-CoA-S), β-hydroxy-β-methylglutaryl-CoA reductase (HMG-CoA-R), phosphatidylinositol synthase (PI-S), and squalene-synthase (SQ-S). However, the combined treatments with P + 7-10 decreased the expression of GPAT, HMG-CoA-S, and HMG-CoA-R. Expression of mRNA for all enzymes was variable under treatment with T + 7-10. Data showed that these carbamates did not bind to the PR, but inhibited the activity of 5α-reductase. Carbamates 7-10 changed the mRNA expression model induced by T and P in flank organs.

  17. 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.

  18. 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.

  19. 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.

  20. Conformations of flanking bases in HIV-1 RNA DIS kissing complexes studied by molecular dynamics.

    PubMed

    Réblová, Kamila; Fadrná, Eva; Sarzynska, Joanna; Kulinski, Tadeusz; Kulhánek, Petr; Ennifar, Eric; Koca, Jaroslav; Sponer, Jirí

    2007-12-01

    Explicit solvent molecular dynamics simulations (in total almost 800 ns including locally enhanced sampling runs) were applied with different ion conditions and with two force fields (AMBER and CHARMM) to characterize typical geometries adopted by the flanking bases in the RNA kissing-loop complexes. We focus on flanking base positions in multiple x-ray and NMR structures of HIV-1 DIS kissing complexes and kissing complex from the large ribosomal subunit of Haloarcula marismortui. An initial x-ray open conformation of bulged-out bases in HIV-1 DIS complexes, affected by crystal packing, tends to convert to a closed conformation formed by consecutive stretch of four stacked purine bases. This is in agreement with those recent crystals where the packing is essentially avoided. We also observed variants of the closed conformation with three stacked bases, while nonnegligible populations of stacked geometries with bulged-in bases were detected, too. The simulation results reconcile differences in positions of the flanking bases observed in x-ray and NMR studies. Our results suggest that bulged-out geometries are somewhat more preferred, which is in accord with recent experiments showing that they may mediate tertiary contacts in biomolecular assemblies or allow binding of aminoglycoside antibiotics.

  1. [Analysis of conserved flanking elements associated with antibiotic resistance genes dissemination].

    PubMed

    Liu, Jian; Mao, Da-Qing; Ren, Jun; Luo, Yi; Cao, Wen-Qing

    2012-01-01

    The overuse of antibiotics in medicine, animal husbandry, and aquiculture industry increases the emergence of antibiotic resistant bacteria and antibiotic resistance genes (ARGs), and also, accelerates the dissemination of ARGs within environmental bacteria. In this study, the total DNA was directly extracted from environmental samples, and the upstream and downstream of antibiotic resistance genes were directly amplified by thermal asymmetric interlaced PCR (Tail-PCR) technique. By optimizing the Tail-PCR program, the multiple flanking sequences of tetW, including 6 upstream sequences and 9 downstream sequences, were simultaneously acquired. Through the bioinformatics analysis, the upstream of tetW presented a perfect inverted repeat (IR), a known tetW regulator peptide, and an insertional sequence (IS), whereas the downstream of tetW presented a most conservative fragment and a common open reading frame (ORF) coding methyltransferase. This study not only revealed several conserved flanking tetW gene modules, but also supplied a highly-efficient and convenient methodology for the research of tetW's dissemination within bacteria, i. e., several flanking sequences could be concisely obtained from one sample by using Tail-PCR program.

  2. 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.

  3. 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

  4. An application of time-reversed acoustics to the imaging of a salt-dome flank

    NASA Astrophysics Data System (ADS)

    Willis, M. E.; Lu, R.; Campman, X.; Toksöz, N.; Zhang, Y.; de Hoop, M. V.

    2005-12-01

    We present results of applying the concept of time-reversed acoustics (TRA) to the imaging of a salt-dome flank in a v(z) medium. A simulated multi-level walk-away VSP survey with sources at the surface and receivers in the borehole can be sorted into an equivalent reverse VSP (RVSP) with effective downhole sources and surface receivers. We apply the TRA process to the RVSP traces and create a zero offset seismic section as if it had been collected from collocated downhole sources and receivers. This procedure effectively redatums the wavefield from the surface to the borehole, eliminating the need for any complicated processing. The redatummed traces are created by summing the autocorrelations of the traces in the RVSP common shot gather. Theory says that each shot gather should be from receivers which completely surround the source. From practical considerations, we only have available the RVSP common receivers on the earth's surface, so we obtain an approximate zero offset section. Even with this restriction, our example shows that the results are encouraging. The image of the salt dome flank is created from the redatummed traces using a standard post-stack depth migration algorithm. This image compares favorably with the salt dome flank model.

  5. 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

  6. 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

  7. 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.

  8. 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.

  9. Modeling "secular" flank motion at Kilauea Volcano (Hawai'i) during 2000-2003

    NASA Astrophysics Data System (ADS)

    Plattner, C.; Amelung, F.; Baker, S.; Govers, R. M.; Poland, M. P.; Lavallee, Y.

    2011-12-01

    Kilauea's south flank is moving seaward due to flank instabilities. The rate is influenced by magmatic events (dike intrusions) and tectonic events (earthquakes and slow-slip events at the decollement), but the general flank motion signal remains significant at any time, with rates of 6-10 cm/yr during the past decade. The surface displacements were explained by fault slip along the decollement beneath Kilauea combined with deep-rift opening in elastic halfspace dislocation models. While these models explain the kinematics well, the dynamics of the rift opening are not resolved, and the question on contribution from magmatic driving forces versus an entirely gravitationally-driven system remains. InSAR time-series analysis (Small Baseline Algorithm; SBAS) showed linear surface subsidence at Kilauea summit (maximum rate 5.5 cm/yr south of the caldera) during 2000-2003, a time-period during which the influence of distinct deformation events is small in comparison to previous and later time-periods. Here, we investigate if summit subsidence can be explained as a consequence of secular flank motion at Kilauea by ductile creep of a deep magma mush, using a numerical model with time-dependent material deformation properties to constrain velocities rather than displacements. We developed a 2D finite element model that investigates the deformation response of Kilauea to gravitational driving forces only. The model geometry includes a decollement fault beneath the volcano that can have locked and creeping fault segments. We introduce time-dependent material behavior using a viscoelastic model media. The host rock remains stable over geodetic timescales given its high viscosity value, while the deep-seated magma mush beneath Kilauea caldera is assigned a lower viscosity and spreads at significant rates. The deformation signal of the magma mush is transmitted to the surface, causing local subsidence at Kilauea summit, showing that summit subsidence can be explained by flank

  10. Role of large flank-collapse events on magma evolution of volcanoes. Insights from the Lesser Antilles Arc

    NASA Astrophysics Data System (ADS)

    Boudon, Georges; Villemant, Benoît; Friant, Anne Le; Paterne, Martine; Cortijo, Elsa

    2013-08-01

    Flank-collapse events are now recognized as common processes of destruction of volcanoes. They may occur several times on a volcanic edifice pulling out varying volumes of material from km3 to thousands of km3. In the Lesser Antilles Arc, a large number of flank-collapse events were identified. Here, we show that some of the largest events are correlated to significant variations in erupted magma compositions and eruptive styles. On Montagne Pelée (Martinique), magma production rate has been sustained during several thousand years following a 32 ka old flank-collapse event. Basic and dense magmas were emitted through open-vent eruptions that generated abundant scoria flows while significantly more acidic magmas were produced before the flank collapse. The rapid building of a new cone increased the load on magma bodies at depth and the density threshold. Magma production rate decreased and composition of the erupted products changed to more acidic compared to the preceding period of activity. These low density magma generated plinian and dome-forming eruptions up to the Present. In contrast at Soufrière Volcanic Centre of St. Lucia and at Pitons du Carbet in Martinique, the flank-collapses have an opposite effect: in both cases, the acidic magmas erupted immediately after the flank-collapses. These magmas are highly porphyritic (up to 60% phenocrysts) and much more viscous than the magmas erupted before the flank-collapses. They have been generally emplaced as voluminous and uptight lava domes (called “the Pitons”). Such magmas could not ascent without a significant decrease of the threshold effect produced by the volcanic edifice loading before the flank-collapse.

  11. 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.

  12. Radiometric dating of three large volume flank collapses in the Lesser Antilles Arc

    NASA Astrophysics Data System (ADS)

    Samper, A.; Quidelleur, X.; Boudon, G.; Le Friant, A.; Komorowski, J. C.

    2008-10-01

    It is now recognised that flank collapses are a recurrent process in the evolution of the Lesser Antilles Arc volcanoes. Large magnitude debris-avalanche deposits have been identified off the coast of Dominica, Martinique and St. Lucia, with associated volumes up to 20 km 3 [Deplus, C., Le Friant, A., Boudon, G., Komorowski, J.-C., Villemant, B., Harford, C., Ségoufin, J., Cheminée, J.-L., 2001. Submarine evidence for large-scale debris avalanches in the Lesser Antilles Arc. Earth Planet. Sci. Lett., 192: 145-157.]. We present new radiometric dating of three major events using the K-Ar Cassignol-Gillot technique. In the Qualibou depression of St. Lucia, a collapse has been constrained by dome emplacement prior to 95 ± 2 ka. In Dominica, where repetitive flank collapse events have occurred [Le Friant, A., Boudon, G., Komorowski, J.-C., Deplus, C., 2002. L'île de la Dominique, à l'origine des avalanches de débris les plus volumineuses de l'arc des Petites Antilles. C.R. Geoscience, 334: 235-243], the Plat Pays event probably occurred after 96 ± 2 ka. Inside the depression caused by this event, Scotts Head, which is interpreted as a proximal megabloc from the subsequent Soufriere avalanche event has been dated at 14 ± 1 ka, providing an older bound for this event. On Martinique three different domes within the Carbets structure dated at 337 ± 5 ka constrain the age of this high magnitude event. Finally, these results obtained from three of the most voluminous flank collapses provide constraints to estimate the recurrence of these events, which represent one of the major hazards associated with volcanoes of the Lesser Antilles Arc.

  13. Sequence and single-base polymorphisms of the bovine alpha-lactalbumin 5'-flanking region.

    PubMed

    Bleck, G T; Bremel, R D

    1993-04-30

    The alpha-lactalbumin (alpha LA)-encoding gene is a potential quantitative trait locus in dairy animals. In cattle, the production of alpha LA is tightly coupled to the onset of lactation and it serves as a regulatory subunit of the enzyme responsible for lactose synthesis. Lactose is the major osmole controlling water movement in the mammary gland. To better understand the control of bovine alpha LA expression, the 5'-flanking region of a Holstein alpha LA gene was cloned and sequenced. The sequenced clone contains 1952 bp of 5'-flanking region and 66-bp of the protein-coding region. Three single-bp polymorphisms were identified within this region. These polymorphisms occur at positions +15, +21 and +54 relative to the mRNA transcription start point (tsp). The +15 and +21 variations occur in the region encoding the 5'-untranslated region of the mRNA-coding sequence. The +54 polymorphism is a silent mutation in the SP-coding region of the gene. A polymerase chain reaction (PCR, Cetus)-based screening method has been employed to analyze the genotype of cattle at the +15 position. A total of 501 randomly selected cattle from seven breeds were screened for this allele. Of these animals, only the Holstein breed of cattle was found to contain the +15 variation and it occurs at a gene frequency of 32%. Sequence comparisons were conducted between the 5'-flanking regions of the bovine-milk-protein encoding genes, alpha LA, beta-casein and alpha S1-casein, which are coordinately expressed. Regions of similarity extending to 350 bp in length were observed between these sequences.

  14. 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

  15. 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.

  16. Desmoinesian sedimentary history of the northern flank of the Ozark uplift

    SciTech Connect

    Searight, T.K.; Nelson, R.S. . Dept. of Geography-Geology)

    1993-03-01

    The structural framework of the northern flank of the Ozark Uplift during Desmoinesian time was a gradually subsiding platform connecting the Forest City Basin with the Illinois Basin through the St. Louis Depression. The platform was bounded on the northeast and southwest by major lineaments and was internally broken into numerous rigid crustal blocks by northwest- and northeast-trending lineaments. Depositional patterns of the thin cyclic strata, ranging in thickness from a few to several hundred centimeters, were controlled by vertical or rotational movements of these blocks. Pennsylvanian sediments were deposited on an erosion surface cut into Mississippian rocks. This surface is characterized by broad shallow valleys and numerous karst features. The first Pennsylvanian deposits were conglomerates derived from Mississippian chert, and are overlain by the Cheltenham clay. Desmoinesian sediments unconformably overlie the Cheltenham clay in a transgressive sequence from northwest to southeast. Several Desmoinesian cycles present on the western flank of the Ozark Uplift are absent on the northern flank. These cycles are represented by a thickening of the underclays of the Tebo, Croweburg, Wheeler, and Mulky coals which rest on the Cheltenham. Cycles between the Tiawah Limestone and the underclay of the Croweburg Coal are absent. Although abrupt local changes in thicknesses of individual lithotypes are related to movements of rigid blocks, some regional depositional patterns are identifiable. Strata from the base of the underclay of the Tebo Coal through the Lagonda Formation thin and pinch out from northwest to southeast Post-Lagonda strata through the Blackjack Creek Limestone thicken from northwest to southeast. Post-Lagonda deposits are preserved in scattered localities, making definitive interpretations difficult.

  17. Details of an Extinct Rift Embedded on the Western Flank of the Southernmost Mid-Atlantic Ridge

    NASA Astrophysics Data System (ADS)

    Marks, K. M.; Tikku, A. A.; Stock, J. M.; Livermore, R. A.

    2002-05-01

    We have identified a possible extinct rift embedded on the western flank of the southernmost spreading corridors of the Mid-Atlantic ridge (MAR). This rift trends N10° W along 10° W longitude (between about 52° -55° S), northwest of the Bouvet Triple Junction. Elevated topography that slopes away from an axial valley, as well as magnetic anomalies 6b-8 that are symmetrically disposed about the axis, characterize this feature. We initially proposed magnetic anomalies 5a-5b were missing on the western flank of the MAR, and repeated on the eastern flank, which would suggest a second, more recent ridge jump. However detailed swath bathymetry (Ligi et al., JGR, 1999) in the region of the Bouvet Triple Junction reveals a sinistral offset of the MAR at about 2° W, 54.1° S that is consistent with displacement along a transform fault. The associated fracture zone can be traced westward where it crosses ship track a1076 at the location of the 5a-5b gap, thus accounting for the missing anomalies. Further, ship track jr09b shows magnetic anomalies 5a-5b are present on both the east and west MAR flanks. Our new magnetic anomaly interpretation suggests there was a single eastward ridge jump after Chron 6b resulting in anomalies 6b-8 being repeated on the western MAR ridge flank, and missing on the eastern flank. An additional, more recent ridge jump is not indicated.

  18. 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

  19. 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.

  20. "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

  1. 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 Hualālai. 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

  2. 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.

  3. Postmortem Evaluation of Left Flank Laparoscopic Access in an Adult Female Giraffe (Giraffa camelopardalis).

    PubMed

    Pizzi, R; Cracknell, J; Dalrymple, L

    2010-01-01

    There are still few reports of laparoscopy in megavertebrates. The giraffe (Giraffa camelopardalis) is the tallest land mammal, and the largest ruminant species. An 18-year-old multiparous female hybrid giraffe, weighing 650 kg, was euthanized for chronic health problems, and left flank laparoscopy was performed less than 30 minutes after death. Safe primary access was achieved under visualisation using an optical bladed trocar (Visiport Plus, Tyco healthcare UK Ltd) without prior abdominal insufflation. A left paralumbar fossa approach allowed access to the spleen, rumen, left kidney, and intestines, but did not allow access to the reproductive tract which in nongravid females is intrapelvic in nature. PMID:20445792

  4. Soil radon monitoring in the NE flank of Mt. Etna (Sicily).

    PubMed

    Immè, G; La Delfa, S; Lo Nigro, S; Morelli, D; Patanè, G

    2006-05-01

    Soil radon has been monitored at a fixed location on the northeastern flank of Mt. Etna, a high-risk volcano in Sicily. The aim of this study was to evaluate the effects of the recent volcanic activity on soil radon concentration. Continuous radon measurements have been performed since July 2001. While comparison between the trend in in-soil radon concentration and the acquired meteorological series (temperature, humidity and pressure) appear to confirm a general seasonal correlation, nevertheless particular anomalies suggest a possible dependence of the radon concentration on volcanic dynamics. PMID:16413194

  5. Soil radon monitoring in the NE flank of Mt. Etna (Sicily).

    PubMed

    Immè, G; La Delfa, S; Lo Nigro, S; Morelli, D; Patanè, G

    2006-05-01

    Soil radon has been monitored at a fixed location on the northeastern flank of Mt. Etna, a high-risk volcano in Sicily. The aim of this study was to evaluate the effects of the recent volcanic activity on soil radon concentration. Continuous radon measurements have been performed since July 2001. While comparison between the trend in in-soil radon concentration and the acquired meteorological series (temperature, humidity and pressure) appear to confirm a general seasonal correlation, nevertheless particular anomalies suggest a possible dependence of the radon concentration on volcanic dynamics.

  6. Role of large flank-collapse events on magma evolution of volcanoes. Insights from the Lesser Antilles Arc

    NASA Astrophysics Data System (ADS)

    Boudon, G.; Villemant, B.; Le Friant, A.; Paterne, M.; Cortijo, E.

    2012-12-01

    Flank-collapse events are now recognized as common process of destruction of volcanoes. They can occur several times on a volcanic edifice and may involve a large range of volume of material from km3 to thousands of km3. Large flank-collapse events may have significant effects on magma eruption and evolution. The load exerted by the volcanic edifice on the plumbing system and the magma chamber acts as a density filter for magma ascent. Magmas denser than the density threshold are stored within the magma chamber where they differentiate and thus become less dense with time which favours their eruption. When a flank-collapse event occurs the edifice load suddenly decreases which decreases the density threshold allowing denser magmas to ascend and erupt. Thus construction and destruction of volcanic edifices may control both differentiation and eruptive processes. In the Lesser Antilles Arc, a large number of flank-collapse events have been identified. Here, we show that some of the largest events are correlated to significant variations in erupted magma compositions and eruptive styles. On Montagne Pelée, after the 32 kys old flank-collapse event, the magma production rate is sustained during several thousand years: basic and dense magmas were emitted through open-vent eruptions that generated abundant scoria flows. The pre-flank collapse activity produced significantly more acidic magmas. The rapid building of a new cone after the flank collapse progressively increased the load and the density threshold, leading to a decrease in magma production rate and a change in the magma composition of the erupted products. They are more acidic and less dense and thus generate plinian and dome-forming eruptions up to present. On the contrary, at Soufrière Volcanic Centre of St Lucia and at Pitons du Carbet in Martinique, the flank collapses have an opposite effect: in both cases, more acidic magmas erupted after the flank collapse events. These magmas are highly crystallized

  7. Splicing of intron 3 of human BACE requires the flanking introns 2 and 4.

    PubMed

    Annies, Maik; Stefani, Muriel; Hueber, Andreas; Fischer, Frauke; Paganetti, Paolo

    2009-10-16

    Regulation of proteolytic cleavage of the amyloid precursor protein by the aspartic protease BACE may occur by alternative splicing and the generation of enzymatically inactive forms. In fact, the presence of exonic donor and acceptor sites for intron 3 generates the two deficient variants BACE457 and BACE476. In HEK293 cells, when introns are inserted separately in the BACE cDNA, we found that whilst introns 2 and 4 are efficiently spliced out, intron 3 is not removed. On the other hand, splicing to wild-type BACE is restored when intron 3 is flanked by the two other introns. The presence of all three introns also leads to alternative splicing of intron 3 and the generation of BACE476. In contrast, BACE457 expression takes place only after mutating the donor splice site of intron 3, indicating that additional regulatory elements are necessary for the use of the splicing site within exon 4. Overall, our data demonstrate that a complex splicing of intron 3 regulates the maturation of the BACE mRNA. This appears orchestrated by domains present in the exons and introns flanking intron 3. Excessive BACE activity is a risk factor for Alzheimer's disease, therefore this complex regulation might guarantee low neuronal BACE activity and disease prevention.

  8. Flanking markers bracket the neurofibromatosis type 2 (NF2) gene on chromosome 22.

    PubMed Central

    Rouleau, G A; Seizinger, B R; Wertelecki, W; Haines, J L; Superneau, D W; Martuza, R L; Gusella, J F

    1990-01-01

    Neurofibromatosis 2 or bilateral acoustic neurofibromatosis (NF2) is a severe autosomal dominant disorder characterized by the development of multiple tumors of the nervous system, including meningiomas, gliomas, neurofibromas, ependymomas, and particularly acoustic neuromas. Polymorphic DNA markers have revealed frequent loss of one copy of chromosome 22 in the tumor types associated with NF2. Family studies have demonstrated that the primary defect in NF2 is linked to DNA markers on chromosome 22, suggesting that it involves inactivation of a tumor suppressor gene. We have employed a combination of multipoint linkage analysis and examination of deletions in primary tumor specimens to precisely map the NF2 locus between flanking polymorphic DNA markers on chromosome 22. The 13-cM region bracketed by these markers corresponds to 13% of the genetic length of the long arm of chromosome 22 and is expected to contain less than 5 x 10(6) bp of DNA. The delineation of flanking markers for NF2 should permit accurate presymptomatic and prenatal diagnosis for the disorder and greatly facilitate efforts to isolate the defective gene on the basis of its location. Images Figure 1 Figure 3 PMID:2105641

  9. 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.

  10. 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.

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

    PubMed Central

    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

  12. 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

  13. 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.

  14. 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.

  15. Phylogenetic inference and comparative evolution of a complex microsatellite and its flanking regions in carnivores.

    PubMed

    Domingo-Roura, Xavier; López-Giráldez, Francesc; Saeki, Midori; Marmi, Josep

    2005-06-01

    We sequenced locus Mel 08, with complex short repetitive motifs, in 24 carnivore species belonging to five different families in order to explore mutational changes in the region in the context of locus and species evolution. This non-coding locus includes up to four different parts or repetitive motifs showing size variability. The variability consists of repeat additions and deletions; substitutions, insertions and/or deletions creating interruptions in the repeat; and substitutions, insertions and deletions in the flanking regions. The locus has different repeat expansions in different carnivore subfamilies. We hypothesize that the complexity of this locus is due to a high mutation rate at an ancestral DNA sequence and, thus, prompts the emergence of repeats at mutational hotspots. High levels of homoplasy were evident, with nine electromorphs representing 28 haplotypes never shared across species. The variability in flanking regions was informative for phylogenetic inference and their evolutionary content. Tree topologies were congruent with relevant hypotheses on current conflicts in carnivore phylogenies, such as: (i) the monophyly of Lutrinae, (ii) the paraphyly of Mustelinae, (iii) the basal position of the Eurasian badger, Meles meles , in the Mustelidae, (iv) the classification of skunks as a separate family, Mephitidae, and (v) the placement of the red panda, Ailurus fulgens , as a monotypic family, Ailuridae, at a basal position in the Musteloidea.

  16. Renal infarction versus pyelonephritis in a woman presenting with fever and flank pain.

    PubMed

    Piccoli, Giorgina B; Priola, Adriano M; Vigotti, Federica N; Guzzo, Gabriella; Veltri, Andrea

    2014-08-01

    Patients with fever, flank pain, and dysuria frequently are encountered in the emergency department. Acute pyelonephritis is the most likely diagnosis; however, its clinical and radiologic presentation consistently overlap with that of acute renal infarction. Ultrasound is unable to distinguish early infarction from nonabscessed acute pyelonephritis. Hence, computed tomography or magnetic resonance imaging are needed. We report the case of a 68-year-old woman who presented with fever, flank pain, and dysuria, along with respiratory distress and tachycardia. Elevated values for inflammatory indexes suggested a diagnosis of acute pyelonephritis, and subsequent contrast-enhanced computed tomography showed hypodense wedge-shaped areas in both kidneys. However, the presence of a thin rim of capsular enhancement (cortical rim sign), the absence of perirenal inflammatory changes, and the location of the lesions apart from defined calyces suggested the alternative diagnosis of renal infarction. The underlying cause was not identified until an episode of acute dyspnea revealed paroxysmal arrhythmia. Our case demonstrates that a thorough knowledge of the imaging findings of renal infarction and acute pyelonephritis is essential to correctly making the diagnosis.

  17. Hydrothermal recharge and discharge across 50 km guided by seamounts on a young ridge flank.

    PubMed

    Fisher, A T; Davis, E E; Hutnak, M; Spiess, V; Zühlsdorff, L; Cherkaoui, A; Christiansen, L; Edwards, K; Macdonald, R; Villinger, H; Mottl, M J; Wheat, C G; Becker, K

    2003-02-01

    Hydrothermal circulation within the sea floor, through lithosphere older than one million years (Myr), is responsible for 30% of the energy released from plate cooling, and for 70% of the global heat flow anomaly (the difference between observed thermal output and that predicted by conductive cooling models). Hydrothermal fluids remove significant amounts of heat from the oceanic lithosphere for plates typically up to about 65 Myr old. But in view of the relatively impermeable sediments that cover most ridge flanks, it has been difficult to explain how these fluids transport heat from the crust to the ocean. Here we present results of swath mapping, heat flow, geochemistry and seismic surveys from the young eastern flank of the Juan de Fuca ridge, which show that isolated basement outcrops penetrating through thick sediments guide hydrothermal discharge and recharge between sites separated by more than 50 km. Our analyses reveal distinct thermal patterns at the sea floor adjacent to recharging and discharging outcrops. We find that such a circulation through basement outcrops can be sustained in a setting of pressure differences and crustal properties as reported in independent observations and modelling studies.

  18. DNase I hypersensitive sites flank the mouse class II major histocompatibility complex during B cell development.

    PubMed Central

    Carson, S

    1991-01-01

    The mouse class II major histocompatibility complex (MHC) encodes a polymorphic, multigene family important in the immune response, and is expressed mainly on mature B cells, on certain types of dendritic cells and is also inducible by gamma-interferon on antigen presenting cells. To study the regulatory elements which control this expression pattern, we have examined the chromatin structure flanking the class II MHC region, in particular during B cell differentiation. Using a panel of well-characterised mouse cell lines specific for different stages of B cell development (pre-B, B, plasma cell) as well as non-B cell lines, we have mapped the DNase I hypersensitive (DHS) sites adjacent to the mouse MHC class II region. The results presented show, for the first time that there are specific hypersensitive sites flanking the class II MHC locus during pre B cell, B cell and plasma cell stages of B cell differentiation, irrespective of the status of class II MHC expression. These hypersensitive sites are not found in T cell, fibroblast or uninduced myelomonocytic cell lines. This suggests that these DHS sites define a developmentally stable, chromatin structure, which can be used as a marker of B cell lineage commitment and may indicate that a combination of these hypersensitive sites reflect regulatory proteins involved in the immediate expression of a particular class II MHC gene or possibly control of the entire locus. Images PMID:1923768

  19. 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.

  20. 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

  1. Recombineering-based dissection of flanking and paralogous Hox gene functions in mouse reproductive tracts.

    PubMed

    Raines, Anna M; Adam, Mike; Magella, Bliss; Meyer, Sara E; Grimes, H Leighton; Dey, Sudhansu K; Potter, S Steven

    2013-07-01

    Hox genes are key regulators of development. In mammals, the study of these genes is greatly confounded by their large number, overlapping functions and interspersed shared enhancers. Here, we describe the use of a novel recombineering strategy to introduce simultaneous frameshift mutations into the flanking Hoxa9, Hoxa10 and Hoxa11 genes, as well as their paralogs on the HoxD cluster. The resulting Hoxa9,10,11 mutant mice displayed dramatic synergistic homeotic transformations of the reproductive tracts, with the uterus anteriorized towards oviduct and the vas deferens anteriorized towards epididymis. The Hoxa9,10,11 mutant mice also provided a genetic setting that allowed the discovery of Hoxd9,10,11 redundant reproductive tract patterning function. Both shared and distinct Hox functions were defined. Hoxd9,10,11 play a crucial role in the regulation of uterine immune function. Non-coding non-polyadenylated RNAs were among the key Hox targets, with dramatic downregulation in mutants. We observed Hox cross-regulation of transcription and splicing. In addition, we observed a surprising anti-dogmatic apparent posteriorization of the uterine epithelium. In caudal regions of the uterus, the normal simple columnar epithelium flanking the lumen was replaced by a pseudostratified transitional epithelium, normally found near the more posterior cervix. These results identify novel molecular functions of Hox genes in the development of the male and female reproductive tracts.

  2. Steady downslope movement on the western flank of Arenal Volcano, Costa Rica

    NASA Astrophysics Data System (ADS)

    Ebmeier, S. K.; Biggs, J.; Mather, T. A.; Wadge, G.; Amelung, F.

    2010-12-01

    We present InSAR measurements of slow gravity driven slip on the flanks of Volcan Arenal, Costa Rica between 2005 and 2009. The deformation of a volcanic edifice depends on both active volcanic processes, and its composition, structure and morphology. Using interferograms from both ALOS and RadarSat, we observe that Arenal's western flanks are moving downslope at an angle of ~55 degrees below the horizontal plane at a consistent rate of ~7cm/yr. We use the pattern, rate and direction of motion to test several hypotheses for its origin and conclude that neither magmatic activity nor the subsidence of young lava can be the primary source for the deformation. Our favoured explanation is creep along a shallow sliding plane, most likely the interface between deposits post-dating the 1968 lateral blast eruption and the older lavas and paleosoils beneath. Our measurement of slope movement adds to a small set of rate measurements for gravity driven deformation at volcanoes and is distinctive in both its relatively high rate and shallow origin. Observation of deformation at Arenal contributes both to the assessment of particular hazards around Arenal itself, and more generally, to the study of the stability of young stratovolcanoes.

  3. 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

  4. A Nucleotide-Driven Switch Regulates Flanking DNA Length Sensing by a Dimeric Chromatin Remodeler

    PubMed Central

    Leonard, John D.; Narlikar, Geeta J.

    2015-01-01

    SUMMARY The ATP-dependent chromatin assembly factor (ACF) is a dimeric motor that spaces nucleosomes to promote formation of silent chromatin. Two copies of its ATPase subunit SNF2h bind opposite sides of a nucleosome, but how these protomers avoid competition is unknown. SNF2h senses the length of DNA flanking a nucleosome via its HAND-SANT-SLIDE (HSS) domain, yet it is unclear how this interaction enhances remodeling. Using covalently connected SNF2h dimers we show that dimerization accelerates remodeling and that the HSS contributes to communication between protomers. We further identify a nucleotide-dependent conformational change in SNF2h. In one conformation the HSS binds flanking DNA, and in another conformation the HSS engages the nucleosome core. Based on these results, we propose a model in which DNA length sensing and translocation are performed by two distinct conformational states of SNF2h. Such separation of function suggests that these activities could be independently regulated to affect remodeling outcomes. PMID:25684208

  5. Microarray Analyses and Comparisons of Upper or Lower Flanks of Rice Shoot Base Preceding Gravitropic Bending

    PubMed Central

    Zang, Aiping; Chen, Haiying; Dou, Xianying; Jin, Jing; Cai, Weiming

    2013-01-01

    Gravitropism is a complex process involving a series of physiological pathways. Despite ongoing research, gravitropism sensing and response mechanisms are not well understood. To identify the key transcripts and corresponding pathways in gravitropism, a whole-genome microarray approach was used to analyze transcript abundance in the shoot base of rice (Oryza sativa sp. japonica) at 0.5 h and 6 h after gravistimulation by horizontal reorientation. Between upper and lower flanks of the shoot base, 167 transcripts at 0.5 h and 1202 transcripts at 6 h were discovered to be significantly different in abundance by 2-fold. Among these transcripts, 48 were found to be changed both at 0.5 h and 6 h, while 119 transcripts were only changed at 0.5 h and 1154 transcripts were changed at 6 h in association with gravitropism. MapMan and PageMan analyses were used to identify transcripts significantly changed in abundance. The asymmetric regulation of transcripts related to phytohormones, signaling, RNA transcription, metabolism and cell wall-related categories between upper and lower flanks were demonstrated. Potential roles of the identified transcripts in gravitropism are discussed. Our results suggest that the induction of asymmetrical transcription, likely as a consequence of gravitropic reorientation, precedes gravitropic bending in the rice shoot base. PMID:24040303

  6. 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).

  7. Characterization of the Nanog 5′-flanking Region in Bovine

    PubMed Central

    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

    2016-01-01

    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

  8. 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

  9. 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

  10. 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.

  11. Distinct sources of particles near the cusp and the dusk flank of the magnetosphere

    NASA Astrophysics Data System (ADS)

    Escoubet, C. P.; Grison, B.; Berchem, J.; Trattner, K. J.; Lavraud, B.; Pitout, F.; Soucek, J.; Richard, R. L.; Laakso, H. E.; Masson, A.; Dunlop, M.; Dandouras, I. S.; Rème, H.; Fazakerley, A. N.; Daly, P. W.

    2015-12-01

    At the magnetopause, the location of the magnetic reconnection sites depends on the orientation of the interplanetary magnetic field (IMF) in the solar wind: on the dayside magnetosphere for an IMF southward, on the lobes for an IMF northward and on the flanks for an IMF in the East-West direction. Since most of observations of reconnection events have sampled a limited region of space simultaneously it is still not yet know if the reconnection line is extended over large regions of the magnetosphere or if is patchy and made of many reconnection lines. We report a Cluster crossing on 5 January 2002 near the exterior cusp on the southern dusk side where we observe multiple sources of reconnection/injections. The IMF was mainly azimuthal (IMF-By around -5 nT), the solar wind speed lower than usual around 280 km/s with the density of order 5 cm-3. The four Cluster spacecraft had an elongated configuration near the magnetopause. C4 was the first spacecraft to enter the cusp around 19:52:04 UT, followed by C2 at 19:52:35 UT, C1 at 19:54:24 UT and C3 at 20:13:15 UT. C4 and C1 observed two ion energy dispersions at 20:10 UT and 20:40 UT and C3 at 20:35 UT and 21:15 UT. Using the time of flight technique on the upgoing and downgoing ions, which leads to energy dispersions, we obtain distances of the ion sources between 14 and 20 RE from the spacecraft. The slope of the ion energy dispersions confirmed these distances. Using Tsyganenko model, we find that these sources are located on the dusk flank, past the terminator. The first injection by C3 is seen at approximately the same time as the 2nd injection on C1 but their sources at the magnetopause were separated by more than 7 RE. This would imply that two distinct sources were active at the same time on the dusk flank of the magnetosphere. In addition, a flow reversal was observed at the magnetopause on C4 which would be an indication that reconnection is also taking place near the exterior cusp quasi-simultaneously. A

  12. Lateral Dispersion of Volcanic Ash From the Flanks of an Actively Erupting Submarine Volcano

    NASA Astrophysics Data System (ADS)

    Walker, S. L.; Baker, E. T.; Resing, J. A.; Lebon, G. T.; Lupton, J. E.; Greene, R. R.

    2006-12-01

    NW Rota-1 is an actively erupting submarine volcano along the Mariana Arc, rising some 2500 m from the local seafloor. Eruptions at Brimstone Pit, located about 30 m below the summit on the south side of the volcano at 550 m water depth, have been directly observed since 2004. Water column surveys (using CTD-O vertical cast and tow methods) in 2003, 2004 and 2006 mapped the distribution of both persistent and variable particle plumes over the summit and down the flanks. In all years, there was a non-buoyant laterally dispersing plume over the summit that was optically intense and very thin (25-30 m plume maximum), measurable up to 2-3 km from the summit. The plume was most intense in 2003 and 2004 with dNTU values reaching 5 (the upper limit of the optical backscatter sensor). High concentrations of particulate sulfur in the plume contribute to these unusually intense optical signals, as sulfur particles are efficient optical backscatters. The plume maxima depth has steadily declined over 3 years: 460 m in 2003, 485 m in 2004, and 505-530 m in 2006. In 2003, both hydrothermal and volcanic components were detected in the plume, so it is not certain that the 2003 data represent pre-eruption conditions. Deeper layers of turbidity were absent in 2003, but were observed in multiple layers surrounding the volcano in 2004 and 2006 from depths of about 700 m extending to >2500 m, and were detectable at distances up to 18 km from the summit. Microscopy and chemical analysis indicates that the particles in these layers are overwhelmingly glass fragments rather than hydrothermal precipitates. Over the scale of 3-6 days, repeat tows showed significant decreases in particle concentrations, implying some of the particles settled rapidly from these plumes. The most likely source of these layers is gravity flow of volcanic ash down the flanks, fed by violent eruptions at the summit. Detachment from the seafloor may be controlled by turbulence from current flow or internal waves

  13. Biogeochemical Fluxes Across the Juan de Fuca Ridge-Flank: Minor and Trace Element Systematics

    NASA Astrophysics Data System (ADS)

    Hulme, S. M.; Wheat, C. G.; Jannasch, H. W.

    2006-12-01

    Crustal ridge-flank hydrothermal convection of seawater profoundly affects; global geochemical fluxes and cycles, plate tectonics through crustal cooling, and the deep biosphere. Comprehensive assessment of chemical fluxes from this type of hydrothermal circulation has been obscured by sampling artifacts during sample retrieval and extraction from drilling and the lack of uncontaminated in situ samples. With the development of sealed borehole observatories (CORKs) it is now possible to obtainable uncontaminated crustal formation fluids. The Endeavor Segment of the Juan de Fuca Ridge presented an ideal region for addressing the effects of ridge flank hydrothermal circulation on global processes because of direct access to basement fluids through six CORKs and the known composition of nearby spring fluids. We present data from fluids collected via osmotically-pumped continuous fluid samplers (OsmoSamplers) from within sealed boreholes. Methods using high-resolution ICP-MS were developed to allow analysis of trace elements (V, Cr, Co, Ni, Cu, Zn, Rb, Y, Mo, Cd, Cs, Ba, and U) and the entire suite of rare-earth elements in 5ml of sample. Fluids from OsmoSamplers deployed at 3 drill sites (1024, 1026, and 1027) were analyzed along with borehole fluids collected at two additional sites (1025 and 1026). Pore fluids from multiple drilling legs were also compared for sampling artifacts associated with differing sediment core collection techniques. The results of this study determined which trace elements can be accurately determined from ocean drilling and pore water extraction from sediments and borehole sampling by comparison with the time-integrated samples obtained from within the sealed boreholes. Once the accurate composition of basement fluids was determined, it was possible to examine regional trends of the hydrothermal aquifer system both along and across strike of the ridge axis. These data of crustal fluids can then be compared to pore fluids collected during

  14. Cluster Observations of reconnection along the dusk flank of the magnetosphere

    NASA Astrophysics Data System (ADS)

    Escoubet, C.-Philippe; Grison, Benjamin; Berchem, Jean; Trattner, Karlheinz; Lavraud, Benoit; Pitout, Frederic; Soucek, Jan; Richard, Robert; Laakso, Harri; Masson, Arnaud; Dunlop, Malcolm; Dandouras, Iannis; Reme, Henri; Fazakerley, Andrew; Daly, Patrick

    2015-04-01

    Magnetic reconnection is generally accepted to be the main process that transfers particles and energy from the solar wind to the magnetosphere. The location of the reconnection site depends on the orientation of the interplanetary magnetic field (IMF) in the solar wind: on the dayside magnetosphere for an IMF southward, on the lobes for an IMF northward and on the flanks for an IMF in the East-West direction. Since most of observations of reconnection events have sampled a limited region of space simultaneously it is still not yet know if the reconnection line is extended over large regions of the magnetosphere or if is patchy and made of many reconnection lines. We report a Cluster crossing on 5 January 2002 near the exterior cusp on the southern dusk side where we observe multiple sources of reconnection/injections. The IMF was mainly azimuthal (IMF-By around -5 nT), the solar wind speed lower than usual around 280 km/s with the density of order 5 cm-3. The four Cluster spacecraft had an elongated configuration near the magnetopause. C4 was the first spacecraft to enter the cusp around 19:52:04 UT, followed by C2 at 19:52:35 UT, C1 at 19:54:24 UT and C3 at 20:13:15 UT. C4 and C1 observed two ion energy dispersions at 20:10 UT and 20:40 UT and C3 at 20:35 UT and 21:15 UT. Using the time of flight technique on the upgoing and downgoing ions, which leads to energy dispersions, we obtain distances of the ion sources between 14 and 20 RE from the spacecraft. The slope of the ion energy dispersions confirmed these distances. Using Tsyganenko model, we find that these sources are located on the dusk flank, past the terminator. The first injection by C3 is seen at approximately the same time as the 2nd injection on C1 but their sources at the magnetopause were separated by more than 7 RE. This would imply that two distinct sources were active at the same time on the dusk flank of the magnetosphere. In addition, a flow reversal was observed at the magnetopause on C4

  15. Manifestations of hydrothermal discharge from young abyssal hills on the fast-spreading East Pacific Rise flank

    NASA Astrophysics Data System (ADS)

    Haymon, Rachel M.; MacDonald, Ken C.; Benjamin, Sara B.; Ehrhardt, Christopher J.

    2005-02-01

    Spectacular black smokers along the mid-ocean-ridge crest represent a small fraction of total hydrothermal heat loss from ocean lithosphere. Previous models of measured heat flow suggest that 40% 50% of oceanic hydrothermal heat and fluid flux is from young seafloor (0.1 5 Ma) on mid-ocean-ridge flanks. Despite evidence that ridge-flank hydrothermal flux affects crustal properties, ocean chemistry, and the deep-sea biosphere, few ridge-flank vent sites have been discovered. We describe the first known seafloor expressions of hydrothermal discharge from tectonically formed abyssal hills flanking a fast-spreading ridge. Seafloor manifestations of fluid venting from two young East Pacific Rise abyssal hills (0.1 Ma at 10°20‧N, 103°33.2‧W; 0.5 Ma at 9°27‧N, 104°32.3‧W) include fault-scarp hydrothermal mineralization and macrofauna; fault-scarp flocculations containing hyperthermophilic microbes; and hilltop sediment mounds and craters possibly created by fluid expulsion. These visible features can be exploited for hydrothermal exploration of the vast abyssal hill terrain flanking the mid-ocean ridge and for access to the subseafloor biosphere. Petrologic evidence suggests that abyssal hills undergo repeated episodes of transitory fluid discharge, possibly linked to seismic events, and that fluid exit temperatures can be briefly high enough to transport copper (≥250 °C).

  16. 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

  17. Synthetic direct impact light curves of the ultracompact AM CVn binary systems V407 Vul and HM Cnc

    NASA Astrophysics Data System (ADS)

    Wood, M. A.

    2009-05-01

    The interacting binary white dwarf (AM CVn) systems HM Cnc and V407 have orbital periods of 5.4 and 9.5 min, respectively. The two systems are characterized by an `on/off' behaviour in the X-ray light curve, and optical light curves that are nearly sinusoidal and which lead the X-ray light curves in phase by about 0.2 in both systems. Of the models that have been proposed to explain the observations, the one that seems to require the least fine-tuning is the direct impact model of Marsh & Steeghs. In this model, the white dwarf primary is large enough relative to the semimajor axis that the accretion stream impacts the surface of the primary white dwarf directly without forming an accretion disc. Marsh & Steeghs proposed that in this situation there could be a flow setup around the equator with a decreasing surface temperature, the further one measured from the impact point. In this study, we estimate the light curves that might result from such a temperature distribution, and find them to be reasonable approximations to the observations. One unexpected result is that two distinct X-ray spots must exist to match the shape of the X-ray light curves.

  18. 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

  19. Thermochronologic constraints on Jurassic rift flank denudation in the Thiel Mountains, Antarctica

    USGS Publications Warehouse

    Fitzgerald, P.G.; Baldwin, S.L.

    2007-01-01

    The Thiel Mountains are part of the Transantarctic Mountains (TAM) and occupy a strategic position close to the East-West Antarctic boundary. They occur in a region of relatively subdued topography distal from high topography and high relief of most of the TAM adjacent to the West Antarctic rift system. Low-temperature thermochronology on samples collected from the Reed Ridge granite on the north flank of the Thiel Mountains constrain the thermal and hence tectonic history. Apatite fission track data plus thermal models indicate cooling from ca. 165-150 Ma. In conjunction with 40Ar/39Ar K-feldspar data, the results indicate cooling was due to relatively slow erosional denudation, and not thermal relaxation following Jurassic tholeiitic magmatism. Denudation was most likely associated with the formation of the Jurassic rift system across Antarctica that marked the initial breakup of Gondwana. This is the oldest episode of denudation associated with formation of the present day TAM

  20. 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.

  1. Significance of linkage disequilibrium between the fragile X locus and its flanking markers

    SciTech Connect

    Chiurazzi, P.; Neri, G.; Macpherson, J.

    1996-07-12

    The identification of several microsatellite markers flanking the FRAXA locus was instrumental in the positional cloning of the FMR1 gene. These markers can still be valuable in family studies, e.g., as additional evidence in prenatal diagnosis. Additionally, they were employed to verify the presence of any significant gametic disequilibrium between the fragile X mutation and some haplotypes, although the high mutation rate predicted from early segregation studies implied that new mutants would arise on almost every chromosomal background. Thus, the discovery of linkage disequilibrium encompassing the fragile X locus has been surprising. Here, we review the available evidence of such gametic association and underline its implications for the mutational mechanism. 50 refs., 1 fig., 2 tabs.

  2. 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.

  3. Late Pleistocene flank collapse of Zempoala volcano (Central Mexico) and the role of fault reactivation

    NASA Astrophysics Data System (ADS)

    Arce, José Luis; Macías, Rodolfo; García Palomo, Armando; Capra, Lucia; Macías, José Luis; Layer, Paul; Rueda, Hernando

    2008-11-01

    Zempoala is an extinct Pleistocene (˜ 0.7-0.8 Ma) stratovolcano that together with La Corona volcano (˜ 0.9 Ma) forms the southern end of the Sierra de las Cruces volcanic range, Central Mexico. The volcano consists of andesitic and dacitic lava flows and domes, as well as pyroclastic and epiclastic sequences, and has had a complex history with several flank collapses. One of these collapses occurred during the late Pleistocene on the S-SE flank of the volcano and produced the Zempoala debris avalanche deposit. This collapse could have been triggered by the reactivation of two normal fault systems (E-W and NE-SW), although magmatic activity cannot be absolutely excluded. The debris avalanche traveled 60 km to the south, covers an area of 600 km 2 and has a total volume of 6 km 3, with a calculated Heim coefficient (H/L) of 0.03. Based on the textural characteristics of the deposit we recognized three zones: proximal, axial, and lateral distal zone. The proximal zone consists of debris avalanche blocks that develop a hummocky topography; the axial zone corresponds with the main debris avalanche deposit made of large clasts set in a sandy matrix, which transformed to a debris flow in the lateral distal portion. The deposit is heterolithologic in composition, with dacitic and andesitic fragments from the old edifice that decrease in volume as bulking of exotic clasts from the substratum increase. Several cities (Cuernavaca, Jojutla de Juárez, Alpuyeca) with associated industrial, agricultural, and tourism activities have been built on the deposit, which pose in evidence the possible impact in case of a new event with such characteristics, since the area is still tectonically active.

  4. 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

  5. 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.

  6. 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

  7. 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.

  8. 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.

  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. 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.; Boardman, M.

    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. 

  11. 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

  12. 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

  13. 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

  14. Alignment of (dA).(dT) homopolymer tracts in gene flanking sequences suggests nucleosomal periodicity in D. discoideum DNA.

    PubMed

    Marx, K A; Hess, S T; Blake, R D

    1994-08-01

    It has been shown that the frequency versus size distribution of A and T overlapping and non-overlapping homopolymer tracts of N > 5 in D. discoideum gene flanking and intron regions are significantly greater than in coding regions(1). In the present report, we demonstrate, that a spatial periodicity exists in long A and T tracts (N > 10) in long flanking sequences by scored alignments of those tracts (N > 10) with the nucleosomal repeat. A tract spacing was found at 185-190 bp that corresponds to a maximum alignment score. This is exactly the average spacing of D. discoideum nucleosomes determined experimentally. A majority of A and T tracts in flanking sequences are often spaced by short DNA stretches and the total length of adjacent A and T tracts plus the interrupting short DNA stretch corresponds closely to the average experimentally measured nucleosomal linker DNA size in D. discoideum-42 bp. These data suggest a model which has A and T runs of N > 10 bp in flanking DNA of D. discoideum organized in a regular phase with nonhomopolymer sequences along the DNA. This model has functional implications for A and T tracts, suggesting that they are found in nucleosomal linker DNA regions of chromatin during some necessary portion(s) of the life of the cell.

  15. The occurrence of Mt Barca flank eruption in the evolution of the NW periphery of Etna volcano (Italy)

    NASA Astrophysics Data System (ADS)

    Branca, S.; Del Carlo, P.; Lo Castro, M. D.; de Beni, E.; Wijbrans, J.

    2009-01-01

    Geological surveys, tephrostratigraphic study, and 40Ar/39Ar age determinations have allowed us to chronologically constrain the geological evolution of the lower NW flank of Etna volcano and to reconstruct the eruptive style of the Mt Barca flank eruption. This peripheral sector of the Mt Etna edifice, corresponding to the upper Simeto valley, was invaded by the Ellittico volcano lava flows between 41 and 29 ka ago when the Mt Barca eruption occurred. The vent of this flank eruption is located at about 15 km away from the summit craters, close to the town of Bronte. The Mt Barca eruption was characterized by a vigorous explosive activity that produced pyroclastic deposits dispersed eastward and minor effusive activity with the emission of a 1.1-km-long lava flow. Explosive activity was characterized by a phreatomagmatic phase followed by a magmatic one. The geological setting of this peripheral sector of the volcano favors the interaction between the rising magma and the shallow groundwater hosted in the volcanic pile resting on the impermeable sedimentary basement. This process produced phreatomagmatic activity in the first phase of the eruption, forming a pyroclastic fall deposit made of high-density, poorly vesicular scoria lapilli and lithic clasts. Conversely, during the second phase, a typical strombolian fall deposit formed. In terms of hazard assessment, the possible occurrence of this type of highly explosive flank eruption, at lower elevation in the densely inhabited areas, increases the volcanic risk in the Etnean region and widens the already known hazard scenario.

  16. Rare case of a strangulated intercostal flank hernia following open nephrectomy: A case report and review of literature

    PubMed Central

    Akinduro, Oluwaseun O.; Jones, Frank; Turner, Jacquelyn; Cason, Frederick; Clark, Clarence

    2015-01-01

    Introduction Flank incisions may be associated with incisional flank hernias, which may progress to incarceration and strangulation. Compromised integrity of the abdominal and intercostal musculature due to previous surgery may be associated with herniation of abdominal contents into the intercostal space. There have been six previously reported cases of herniation into the intercostal space after a flank incision for a surgical procedure. This case highlights the clinical picture associated with an emergent strangulated hernia and highlights the critical steps in its management. Presentation of case We present a case of a 79-year-old adult man with multiple comorbidities presenting with a strangulated flank hernia secondary to an intercostal incision for a right-sided open nephrectomy. The strangulated hernia required emergent intervention including right-sided hemi-colectomy with ileostomy and mucous fistula. Discussion Abdominal incisional hernias are rare and therefore easily overlooked, but may result in significant morbidity or even death in the patient.. The diagnosis can be made with a thorough clinical examination and ultrasound or computed topographical investigation. Once a hernia has become incarcerated, emergent surgical management is necessary to avoid strangulation and small bowel obstruction. Conclusion Urgent diagnosis and treatment of this extremely rare hernia is paramount especially in the setting of strangulation. PMID:26629848

  17. 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.

  18. 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

  19. 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.

  20. 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

  1. 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

  2. Location and extent of recently active lava flows on the eastern flank of Idunn Mons on Venus

    NASA Astrophysics Data System (ADS)

    D'Incecco, Piero; Mueller, Nils; Helbert, Joern; D'Amore, Mario

    2016-10-01

    The eastern flank of Idunn Mons, Imdr Regio's single large volcano, was identified in VIRTIS data as one of the regions with relatively high values of thermal emissivity at 1 μm wavelength. Our study intends to identify location and extent of the sources of such anomalies, thus the lava flows responsible for the relatively high emissivity observed by VIRTIS over the eastern flank of Idunn Mons. We perform a simulation iterating the geologic mapping made over Magellan radar images of the same area with modeling of the blurring caused by the scattering of the 1 μm radiation in the atmosphere. At every iteration, we map the lava flow units in the surroundings of Idunn Mons and we assign each unit an assumed value of emissivity. We observed a good match between the mapped flows and the clusters resulting from the consistency of the mapped lava flows through the ISO clustering analysis. We tested eight different configurations, calculating the total RMS error compared to VIRTIS observations. The best-fit configuration is that where we assigned high values of emissivity to the flank lava flows. Results also show a correlation between the ISO clustering analysis and the best-fit configuration. We reconstructed the post-eruption stratigraphy of the eastern flank of Idunn Mons, displaying the three flank lava flows units likely responsible for the relatively high 1 μm emissivity anomalies observed by VIRTIS. The average microwave emissivity provides a further evidence of the basaltic composition of the mapped lava flows.

  3. 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.

  4. Microbial Inventory of Deeply Buried Oceanic Crust from a Young Ridge Flank.

    PubMed

    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 ~10(4) 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

  5. Repair of naturally occurring mismatches can induce mutations in flanking DNA

    PubMed Central

    Chen, Jia; Miller, Brendan F; Furano, Anthony V

    2014-01-01

    ‘Normal’ genomic DNA contains hundreds of mismatches that are generated daily by the spontaneous deamination of C (U/G) and methyl-C (T/G). Thus, a mutagenic effect of their repair could constitute a serious genetic burden. We show here that while mismatches introduced into human cells on an SV40-based episome were invariably repaired, this process induced mutations in flanking DNA at a significantly higher rate than no mismatch controls. Most mutations involved the C of TpC, the substrate of some single strand-specific APOBEC cytidine deaminases, similar to the mutations that can typify the ‘mutator phenotype’ of numerous tumors. siRNA knockdowns and chromatin immunoprecipitation showed that TpC preferring APOBECs mediate the mutagenesis, and siRNA knockdowns showed that both the base excision and mismatch repair pathways are involved. That naturally occurring mispairs can be converted to mutators, represents an heretofore unsuspected source of genetic changes that could underlie disease, aging, and evolutionary change. DOI: http://dx.doi.org/10.7554/eLife.02001.001 PMID:24843013

  6. Repair of naturally occurring mismatches can induce mutations in flanking DNA.

    PubMed

    Chen, Jia; Miller, Brendan F; Furano, Anthony V

    2014-01-01

    'Normal' genomic DNA contains hundreds of mismatches that are generated daily by the spontaneous deamination of C (U/G) and methyl-C (T/G). Thus, a mutagenic effect of their repair could constitute a serious genetic burden. We show here that while mismatches introduced into human cells on an SV40-based episome were invariably repaired, this process induced mutations in flanking DNA at a significantly higher rate than no mismatch controls. Most mutations involved the C of TpC, the substrate of some single strand-specific APOBEC cytidine deaminases, similar to the mutations that can typify the 'mutator phenotype' of numerous tumors. siRNA knockdowns and chromatin immunoprecipitation showed that TpC preferring APOBECs mediate the mutagenesis, and siRNA knockdowns showed that both the base excision and mismatch repair pathways are involved. That naturally occurring mispairs can be converted to mutators, represents an heretofore unsuspected source of genetic changes that could underlie disease, aging, and evolutionary change.DOI: http://dx.doi.org/10.7554/eLife.02001.001. PMID:24843013

  7. Discovery of a flank caldera and very young glacial activity at Hecates Tholus, Mars.

    PubMed

    Hauber, Ernst; van Gasselt, Stephan; Ivanov, Boris; Werner, Stephanie; Head, James W; Neukum, Gerhard; Jaumann, Ralf; Greeley, Ronald; Mitchell, Karl L; Muller, Peter

    2005-03-17

    The majority of volcanic products on Mars are thought to be mafic and effusive. Explosive eruptions of basic to ultrabasic chemistry are expected to be common, but evidence for them is rare and mostly confined to very old surface features. Here we present new image and topographic data from the High Resolution Stereo Camera that reveal previously unknown traces of an explosive eruption at 30 degrees N and 149 degrees E on the northwestern flank of the shield volcano Hecates Tholus. The eruption created a large, 10-km-diameter caldera approximately 350 million years ago. We interpret these observations to mean that large-scale explosive volcanism on Mars was not confined to the planet's early evolution. We also show that glacial deposits partly fill the caldera and an adjacent depression. Their age, derived from crater counts, is about 5 to 24 million years. Climate models predict that near-surface ice is not stable at mid-latitudes today, assuming a thermo-dynamic steady state. Therefore, the discovery of very young glacial features at Hecates Tholus suggests recent climate changes. We show that the absolute ages of these very recent glacial deposits correspond very well to a period of increased obliquity of the planet's rotational axis.

  8. 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.

  9. 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.

  10. Microbial Inventory of Deeply Buried Oceanic Crust from a Young Ridge Flank.

    PubMed

    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 ~10(4) 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.

  11. Venus - Volcanic Domes on Flank of Volcanic Maat in East Ovda Region

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This Magellan image is centered about 3.2 degrees north latitude, 194.9 degrees longitude in the eastern Ovda region of Venus. The image, which is 90 km (56 miles) in width and 80 km (50 miles) in length, shows some small volcanic domes on the flank of the volcano Maat. The bright flows to the east are most likely rough lava flows while the darker flows to the west are probably smoother flows. The dark flows do show some roughness, however, as can be seen by the structure in the flows to the southwest. These dark flows also have some debris that has been deposited on top of the flows. The debris may be fine material from the surrounding plains on top of the flow by wind or it may be ash from the volcano. Small volcanic domes are very common features on the surface of Venus, indicating that there has been much volcanic activity on the surface. Assuming that the central volcanic cone is symmetrical in shape and knowing the length of the cone's side and the incidence angle, radar foreshortening yields a height and slope of 688 meters and 8.2 degrees, respectively for the cone. These values are similar to heights and slopes of some volcanic cones on the Earth.

  12. 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

  13. 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.

  14. An INDEL polymorphism at the X-STR GATA172D05 flanking region.

    PubMed

    Rodrigues, Elzemar Martins Ribeiro; dos Santos, Ney Pereira Carneiro; dos Santos, Andrea Kely Campos Ribeiro; Marinho, Anderson Nonato; Zago, Marco Antonio; Gomes, Iva; Amorim, António; Gusmão, Leonor; dos Santos, Sidney Emanuel Batista

    2009-01-01

    A new polymorphic INDEL was detected at the X-STR GATA172D05 flanking region, which corresponds to an 18-bp deletion, 141 bp upstream the TAGA repeat motif. This INDEL was found to be polymorphic in different population samples from Native Americans, Africans, and Europeans as well as in an admixed population from the Amazonia (Belém). Gene diversities varied between 37.5% in Native Americans and 49.9% in Africans. Comparison between human and chimpanzee sequences showed that the ancestral state corresponds to the presence of two copies of 18 bp, detected in both species; and the mutated allele has lost one of these two copies. The simultaneous analysis of the short tandem repeat (STR) and INDEL variation showed an association between the INDEL ancestral allele with the shorter STR alleles. High diversities were found in all population groups when combining the information provided by the INDEL and STR variation. Gene diversities varied between 76.7% in Native Americans and 80.6% in both Portugal and Belém.

  15. 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.

  16. The 5'-flanking regions of three pea legumin genes: comparison of the DNA sequences.

    PubMed Central

    Lycett, G W; Croy, R R; Shirsat, A H; Richards, D M; Boulter, D

    1985-01-01

    Approximately 1200 nucleotides of sequence data from the promoter and 5'-flanking regions of each of three pea (Pisum sativum L.) legumin genes (legA, legB and legC) are presented. The promoter regions of all three genes were found to be identical including the "TATA box", and "CAAT box', and sequences showing homology to the SV40 enhancers. The legA sequence begins to diverge from the others about 300bp from the start codon, whereas the other two genes remain identical for another 550bp. The regions of partial homology exhibit deletions or insertions and some short, comparatively well conserved sequences. The significance of these features is discussed in terms of evolutionary mechanisms and their possible functional roles. The legC gene contains a region that may potentially form either of two mutually exclusive stem-loop structures, one of which has a stem 42bp long, which suggests that it could be fairly stable. We suggest that a mechanism of switching between such alternative structures may play some role in gene control or may represent the insertion of a transposable element. PMID:2997721

  17. 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.

  18. Novel microbial assemblages inhabiting crustal fluids within mid-ocean ridge flank subsurface basalt

    PubMed Central

    Jungbluth, Sean P; Bowers, Robert M; Lin, Huei-Ting; Cowen, James P; Rappé, Michael S

    2016-01-01

    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

  19. 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.

  20. Passive, off-axis convection through the southern flank of the Costa Rica rift

    SciTech Connect

    Fisher, A.T.; Becker, K. ); Narasimhan, T.N. ); Langseth, M.G. ); Mottl, M.J. )

    1990-06-10

    Pore fluids are passively convecting through young oceanic sediments and crust around Deep Sea Drilling Project (DSDP) site 504 on the southern flank of the Costa Rica Rift, as inferred from a variety of geological, geochemical, and geothermal observations. The presence of a fluid circulation system is supported by new data collected on Ocean Drilling Program (ODP) leg 111 and a predrilling survey cruise over the heavily sedimented, 5.9 Ma site; during the latter, elongated heat flow anomalies were mapped subparallel to structural strike, with individual measurements of twice the regional mean value, and strong lateral and vertical geochemical gradients were detected in pore waters squeezed from sediment cores. Also, there is a strong correlation between heat flow, bathymetry, sediment thickness, and inferred fluid velocities up through the sediments. Although the forces which drive passive circulation are not well understood, it has generally been thought that the length scale of heat flow variations provides a good indication of the depth of hydrothermal circulation within the oceanic crust. The widely varied geothermal and hydrogeological observations near site 504 are readily explained by a model which combines (1) basement relief, (2) irregular sediment drape, (3) largely conductive heat transfer through the sediments overlying the crust, and (4) thermal and geochemical homogenization of pore fluids at the sediment/basement interface, which results from (5) topographically induced, passive hydrothermal circulation with large aspect ratio, convection cells. This convection involves mainly the permeable, upper 200-300 m of crust; the deeper crust is not involved.

  1. 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.

  2. 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.

  3. Steady downslope movement on the western flank of Arenal volcano, Costa Rica

    NASA Astrophysics Data System (ADS)

    Ebmeier, S. K.; Biggs, J.; Mather, T. A.; Wadge, G.; Amelung, F.

    2010-12-01

    The edifice of a volcano is a unique deformational environment, dependent not just on active volcanic processes but also on its composition, structure, and morphology. We measured the deformation of Volcán Arenal, Costa Rica, using interferograms constructed from both ALOS and RadarSat data between 2005 and 2009. The volcano's western flanks are moving downslope at an angle of ˜55° below the horizontal plane and a consistent rate of at least ˜7 cm/yr. We use the pattern, rate, and direction of motion to test several hypotheses for its origin. Our favored explanation is creep along a shallow sliding plane, most likely the interface between deposits postdating the 1968 lateral blast eruption and the older lavas and paleosoils beneath. Our measurement of slope movement adds to a small set of rate measurements for gravity-driven deformation at volcanoes and is distinctive in both its relatively high rate and shallow origin. Observation of deformation at Arenal contributes both to the assessment of particular hazards around Arenal itself and, more generally, to the study of the stability of young stratovolcanoes.

  4. Genetic analysis of the fragile-X mental retardation syndrome with two flanking polymorphic DNA markers

    SciTech Connect

    Oberle, I.; Heilig, R.; Moisan, J.P.; Kloepfer, C.; Mattei, M.G.; Mattei, J.F.; Boue, J.; Froster-Iskenius, U.; Jacobs, P.A.; Lathrop, G.M.; Lalouel, J.M.

    1986-02-01

    The fragile-X mental retardation syndrome, one of the most prevalent chromosome X-linked diseases (approx. = 1 of 2000 newborn males), is characterized by the presence in affected males and in a portion of carrier females of a fragile site at chromosome band Xq27. The authors have performed a linkage analysis in 16 families between the locus for the fragile-X syndrome, FRAXQ27, and two polymorphic DNA markers that correspond to the anonymous probe St14 and to the coagulation factor IX gene F9. The results indicate that the order of loci is centromere-F9-FRAXQ27-St14-Xqter. The estimate of the recombination fraction for the linkage F9-FRAXQ27 is 0.12 and 0.10 for FRAXQ27-St14. Recombination between St14 and F9 does not appear to be significantly different in normal and fragile-X families. The two flanking probes were used for diagnosis of the carrier state and for detection of transmission of the disease through phenotypically normal males. They should also allow first-trimester diagnosis with a reliability of about 98% in 40% of the families. Used in conjunction with the cytogenetic analysis, the segregation studies with both probes should improve the genetic counseling for the fragile-X syndrome and should be useful for the formal genetic analysis of this unique disease.

  5. 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

  6. Comparison of DNA walking methods for isolation of transgene-flanking regions in GM potato.

    PubMed

    Cullen, Danny; Harwood, Wendy; Smedley, Mark; Davies, Howard; Taylor, Mark

    2011-09-01

    An important aspect in the safety assessment of transgenic plants is the exact location of transgene insertion sites within the host genome. However, robust standard operating procedures are not currently available. Using potato as a test species, different methodologies for the determination of insertion sites using a range of published protocols and commercially available kits were assessed in transgenic lines of varying degrees of complexity, from low copy number to complex re-transformed and co-transformed lines. Three commercial kits, APAgene™ GOLD Genome Walking Kit (BIO S&T), DNA Walking SpeedUp™ Kit II (Seegene), and Universal Vectorette™ System (Sigma) were compared with an adaptor-mediated PCR technique. Overall, the APAgene™ kit was used with a high success rate with low copy number potato lines, and also more complex co- and re-transformed lines, and adhering to key confirmation steps it was possible to obtain flanking sequence ranging in size from 300 to 2,500 bp and eliminate PCR artefacts from the analysis.

  7. 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...

  8. 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

  9. Digestion-ligation-amplification (DLA): a simple genome walking method to amplify unknown sequences flanking mutator (Mu) transposons and thereby facilitate gene cloning.

    PubMed

    Liu, Sanzhen; Hsia, An-Ping; Schnable, Patrick S

    2013-01-01

    Digestion-ligation-amplification (DLA), a novel PCR-based genome walking method, was developed to amplify unknown sequences flanking known sequences of interest. DLA specifically overcomes the problems associated with amplifying genomic sequences flanking high copy number transposons in large genomes. Two DLA-based strategies, MuClone and DLA-454, were developed to isolate Mu-tagged alleles. MuClone allows for the amplification of DNA flanking subsets of the numerous Mu transposons in the genome using unique three-nucleotide tags at the 3'-ends of primers, simplifying the identification of flanking sequences that co-segregate with mutant phenotypes caused by Mu insertions. DLA-454, which combines DLA with 454 pyrosequencing, permits the efficient amplification and sequencing of Mu flanking regions in a high-throughput manner.

  10. 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

  11. Microbial diversity within basement fluids of the sediment-buried Juan de Fuca Ridge flank.

    PubMed

    Jungbluth, Sean P; Grote, Jana; Lin, Huei-Ting; Cowen, James P; Rappé, Michael S

    2013-01-01

    Despite its immense size, logistical and methodological constraints have largely limited microbiological investigations of the subseafloor basement biosphere. In this study, a unique sampling system was used to collect fluids from the subseafloor basaltic crust via a Circulation Obviation Retrofit Kit (CORK) observatory at Integrated Ocean Drilling Program borehole 1301A, located at a depth of 2667 m in the Pacific Ocean on the eastern flank of the Juan de Fuca Ridge. Here, a fluid delivery line directly accesses a 3.5 million years old basalt-hosted basement aquifer, overlaid by 262 m of sediment, which serves as a barrier to direct exchange with bottom seawater. At an average of 1.2 × 10(4) cells ml(-1), microorganisms in borehole fluids were nearly an order of magnitude less abundant than in surrounding bottom seawater. Ribosomal RNA genes were characterized from basement fluids, providing the first snapshots of microbial community structure using a high-integrity fluid delivery line. Interestingly, microbial communities retrieved from different CORKs (1026B and 1301A) nearly a decade apart shared major community members, consistent with hydrogeological connectivity. However, over three sampling years, the dominant gene clone lineage changed from relatives of Candidatus Desulforudis audaxviator within the bacterial phylum Firmicutes in 2008 to the Miscellaneous Crenarchaeotic Group in 2009 and a lineage within the JTB35 group of Gammaproteobacteria in 2010, and statistically significant variation in microbial community structure was observed. The enumeration of different phylogenetic groups of cells within borehole 1301A fluids supported our observation that the deep subsurface microbial community was temporally dynamic.

  12. 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

  13. 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

  14. 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

  15. Dissecting a locus control region: facilitation of enhancer function by extended enhancer-flanking sequences.

    PubMed Central

    Aronow, B J; Ebert, C A; Valerius, M T; Potter, S S; Wiginton, D A; Witte, D P; Hutton, J J

    1995-01-01

    Using transgenic mice, we have defined novel gene regulatory elements, termed "facilitators." These elements bilaterally flank, by up to 1 kb, a 200-bp T-cell-specific enhancer domain in the human adenosine deaminase (ADA) gene. Facilitators were essential for gene copy-proportional and integration site-independent reporter expression in transgenic thymocytes, but they had no effect on the enhancer in transfected T cells. Both segments were required. Individual segments had no activity. A lack of facilitator function caused positional susceptibility and prevented DNase I-hypersensitive site formation at the enhancer. The segments were required to be at opposed ends of the enhancer, and they could not be grouped together. Reversing the orientation of a facilitator segment caused a partial loss of function, suggesting involvement of a stereospecific chromatin structure. trans-acting factor access to enhancer elements was modeled by exposing nuclei to a restriction endonuclease. The enhancer domain was accessible to the 4-cutter DpnII in a tissue- and cell-type-specific fashion. However, unlike DNase I hypersensitivity and gene expression, accessibility to the endonuclease could occur without the facilitator segments, suggesting that an accessible chromatin domain is an intermediate state in the activational pathway. These results suggest that facilitators (i) are distinct from yet positionally constrained to the enhancer, (ii) participate in a chromatin structure transition that is necessary for the DNase I hypersensitivity and the transcriptional activating function of the enhancer, and (iii) act after cell-type-specific accessibility to the enhancer sequences is established by factors that do not require the facilitators to be present. PMID:7823928

  16. 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

  17. Neuropeptide Y and its flanking peptide in human endocrine tumors and plasma.

    PubMed

    Allen, J M; Yeats, J C; Causon, R; Brown, M J; Bloom, S R

    1987-06-01

    Neuropeptide Y (NPY) and its flanking peptide (CPON) were measured in extracts of pheochromocytomas (n = 26), ganglioneuroblastomas (n = 8), and other tumors (n = 95) and plasma (n = 38). NPY was present in high concentrations in the majority of the pheochromocytomas, but was absent in 3 tumors. Similar concentrations of NPY were measured using N- and C-terminal-directed antisera, and there was a good correlation between the concentrations of NPY immunoreactivity and CPON immunoreactivity in the same extracts. Gel permeation chromatography revealed that the separate peptides NPY and CPON were the major products. No significant amounts of a large mol wt precursor containing both immunoreactivities was found. Among the other tumors, 6 of 22 carcinoid tumors, 2 of 2 somatostatinomas, and 3 of 18 insulinomas contained detectable amounts of NPY. Plasma NPY concentrations were very low in normal subjects, and extraction and a 10-fold concentration step were necessary to establish the normal range (0.35-1.25 pmol/L). Plasma NPY concentrations were detectable in unextracted plasma (10 pmol/L) in 50% of patients with pheochromocytomas, but no correlation was found between plasma NPY concentrations and either plasma norepinephrine or epinephrine concentrations. These results indicate that 1) NPY and CPON are present in most, but not all, pheochromocytomas and ganglioneuroblastomas; 2) secretion of NPY immunoreactivity may be independent of that of catecholamines; 3) CPON immunoreactivity is present in plasma of patients with pheochromocytoma; 4) the majority of NPY and CPON immunoreactivities appears to be in the form of the separate free peptide, and there is very little precursor containing both immunoreactivities expressed in these tumors; and 5) NPY immunoreactivity is present in a variety of other endocrine tumors.

  18. Melt inclusion constraints on the magma source of Eyjafjallajökull 2010 flank eruption

    NASA Astrophysics Data System (ADS)

    Moune, S.; Sigmarsson, O.; Schiano, P.; Thordarson, T.; Keiding, J. K.

    2012-09-01

    The 2010 eruptive activity at the Eyjafjallajökull volcanic system began 20 March with a basaltic flank eruption on a 300 m long fissure on the Fimmvörðuháls Pass, in between Eyjafjallajökull and Mýrdalsjökull volcanoes. The magma expelled from the fissure is olivine- and plagioclase-bearing mildly alkali basalt that exhibits uniform and rather primitive whole-rock composition. This event provides a rare opportunity to assess deep magmatic processes in Iceland. Melt inclusions (MIs) hosted in olivine phenocrysts were analyzed for their major, trace and volatile element concentrations to enable identification of magmatic source(s) for Eyjafjallajökull volcano and to better constrain processes occurring at depth. The MIs, in particular those in Mg-rich olivines, record primary magma composition before homogenisation and differentiation during magma ascent. The olivine phenocrysts hosting the MIs have a large compositional range, extending from Fo73 to Fo87, reflecting changes in the magma characteristics from the source to the surface. The MI compositions exhibit significant variations with MgO ranging from 5.2 to 7.2 wt%. This compositional range was caused by a binary mixing of two basaltic end-members followed by fractional crystallization process. The sources of these end-members are identical to those of Katla and Surtsey basalts, with a dominant role of the Katla source. Trace element characteristics of the Fimmvörðuháls MIs suggest important proportions of recycled oceanic crust in their mantle sources.

  19. Microbial diversity within basement fluids of the sediment-buried Juan de Fuca Ridge flank

    PubMed Central

    Jungbluth, Sean P; Grote, Jana; Lin, Huei-Ting; Cowen, James P; Rappé, Michael S

    2013-01-01

    Despite its immense size, logistical and methodological constraints have largely limited microbiological investigations of the subseafloor basement biosphere. In this study, a unique sampling system was used to collect fluids from the subseafloor basaltic crust via a Circulation Obviation Retrofit Kit (CORK) observatory at Integrated Ocean Drilling Program borehole 1301A, located at a depth of 2667 m in the Pacific Ocean on the eastern flank of the Juan de Fuca Ridge. Here, a fluid delivery line directly accesses a 3.5 million years old basalt-hosted basement aquifer, overlaid by 262 m of sediment, which serves as a barrier to direct exchange with bottom seawater. At an average of 1.2 × 104 cells ml−1, microorganisms in borehole fluids were nearly an order of magnitude less abundant than in surrounding bottom seawater. Ribosomal RNA genes were characterized from basement fluids, providing the first snapshots of microbial community structure using a high-integrity fluid delivery line. Interestingly, microbial communities retrieved from different CORKs (1026B and 1301A) nearly a decade apart shared major community members, consistent with hydrogeological connectivity. However, over three sampling years, the dominant gene clone lineage changed from relatives of Candidatus Desulforudis audaxviator within the bacterial phylum Firmicutes in 2008 to the Miscellaneous Crenarchaeotic Group in 2009 and a lineage within the JTB35 group of Gammaproteobacteria in 2010, and statistically significant variation in microbial community structure was observed. The enumeration of different phylogenetic groups of cells within borehole 1301A fluids supported our observation that the deep subsurface microbial community was temporally dynamic. PMID:22791235

  20. The heat shock cognate 80 gene of tomato is flanked by matrix attachment regions.

    PubMed

    Chinn, A M; Comai, L

    1996-12-01

    Matrix attachment regions (MARs) are thought to participate in the organization and segregation of independent chromosomal loop domains. Although there are several reports on the action of MARs in the context of heterologous genes, information is more limited on the role of MARs associated with plant genes. Transgenic studies suggest that the upstream, intron and downstream regions of the developmentally regulated heat shock cognate 80 gene (HSC80) of tomato participate in chromatin organization. In this study, we tested the in vitro affinity of the HSC80 gene to chromosomal scaffolds prepared from shoot apices of tomato. We found that a 1.5 kb upstream region and a 1.4 kb downstream region, but not the intron region, are MARs. These MARs interact with tomato and pea scaffolds and bind regardless of the expression status of HSC80 in the tissue from which the nuclei were isolated. Comparison to two known yeast MARs, ARS1 and CENIII, showed that the HSC80 5'MAR binds more avidly to tomato scaffolds than ARS1, while no binding of CENIII was observed. Competition binding between the two HSC80 MARs indicated that the 5'MAR can outcompete the 3'MAR and not vice versa. Last, we observed that the interaction of the 3'MAR with the scaffold could result in an electrophoretic mobility shift resistant to SDS, protease, and phenol treatment. In conclusion, MARs whose binding properties can be clearly differentiated are closely flanking the HSC80 gene. The discovery of MARs in regions which have a distinct function in HSC80 transgenes but not in transient expression assays, is consistent with a chromosomal scaffold role in HSC80 gene regulation.

  1. 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.

  2. 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.

  3. 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.

  4. Characteristics of the large (dA).(dT) homopolymer tracts in D. discoideum gene flanking and intron sequences.

    PubMed

    Marx, K A; Hess, S T; Blake, R D

    1993-08-01

    D. discoideum, the slime mold, is one of the most AT rich eukaryotic genomes known. In this paper we examine this organism's database for overlapping N-tuples of high frequency and find A and T tracts possess among the highest frequencies in flanking sequences but not in coding sequences. We examined both overlapping and non-overlapping frequencies of the A, T, G and C homopolymer tracts of 2 < N < 6. Overlapping (dG).(dC) and (dA).(dT) tracts occur at greater frequencies than expected, based on random occurrence. Long (dA).(dT) tracts of N > 10 occur at well above expected frequencies in flanking and intron regions, while (dG).(dC) tracts above N = 5 are rarely found. Some of the implications of these findings for tract origins in slip-strand replication and for chromatin structure are discussed.

  5. Co-localization of neuropeptide tyrosine (NPY) and its C-terminal flanking peptide (C-PON).

    PubMed

    Gulbenkian, S; Wharton, J; Hacker, G W; Varndell, I M; Bloom, S R; Polak, J M

    1985-01-01

    Neuropeptide tyrosine (NPY) is one of the most abundant and widespread peptides in the mammalian nervous system. Recent isolation and sequencing of the DNA encoding NPY has predicted the existence of a 97 amino acid precursor peptide. Proteolytic processing of this precursor could yield three separate peptide products, an N-terminal signal peptide, neuropeptide tyrosine and a 30 amino acid C-terminal flanking peptide (C-PON). Here, we present evidence that the predicted C-flanking peptide of NPY is widely distributed in both the central and peripheral nervous systems of several mammalian species including man, and has an identical distribution to NPY. It was also demonstrated, using correlative light microscopic immunostaining on serial sections and double electron microscopic immunocytochemistry, that C-PON and NPY immunoreactivities are co-localized in neuronal cell bodies of the brain cortex, sympathetic ganglion cells, norepinephrine-containing granules of the adrenal medulla and in human pheochromocytoma tumor cells.

  6. 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

  7. [Brood parasitism and egg mimicry on Brownish-flanked Bush Warbler (Cettia fortipes) by Lesser Cuckoo (Cuculus poliocephalus)].

    PubMed

    Yang, Can-Chao; Cai, Yan; Liang, Wei

    2010-10-01

    Nest fate of Brownish-flanked Bush Warbler (Cettia fortipes) was conducted in breeding seasons from 1999 to 2009 in Kuankuoshui Natural Reserve, Guizhou province. Predation rate, parasitism rate, hatching success, nesting success and reproductive success were surveyed and egg color was quantified using spectrophotometer. Principal component analysis, reflectance spectrum and Robinson Project were used to analyze the egg color of bush warbler and egg mimicry of Lesser Cuckoo (Cuculus poliocephalus) in parasitized nests. Our results indicated that the Brownish-flanked Bush Warbler suffered from high predation rate and relatively high parasitism rate of 49.26% and 9.18%, respectively. Reflectance analysis showed that the hue and chroma of Lesser Cuckoo eggs were highly mimetic but the egg brightness and ultraviolet reflectance were different from the bush warbler.

  8. 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

  9. Fluid-sediment Interaction and Formation of Mn oxi-hydroxide related to a Ridge Flank Hydrothermal System

    NASA Astrophysics Data System (ADS)

    Buatier, M. D.; Bodei, S.; Steinmann, M.; Manceau, A.; Karpoff, A.; Guillaume, D.; Wheat, C. G.

    2005-12-01

    Fluid-sediment interaction at ridge flank permits the formation of metalliferous deposits that play a role in the scavenging of Fe, Mn and other trace elements. Several sites of active hydrothermal flow have been found on the eastern flank of Juan de Fuca Ridge (Retroflux) and along the Costa Rica margin (Ticoflux). These sites are typically located along edges of basaltic outcrops and seamounts where the sediment layers are thin. Mn and Fe oxides can be formed at such interfaces. These oxides form soft micro-concretions or slightly indurated black crusts. Detailed investigations combining geochemical (major, trace elements and REEY) and mineralogical (SEM, TEM, EELS EXAFS) analyses of these Mn and Fe-oxides allow formation mechanisms to be proposed. On the eastern flank of the Juan de Fuca Ridge above the 3.5 Ma-old seafloor, amorphous and poorly crystallized Mn-oxides are dispersed in altered sediments whereas pure birnessite is observed as crust layers. Hydrothermal birnessite and well-crystallized todorokite are found in sediments from the Costa Rica margin, on an 18-24 Ma seafloor. Our data suggest that the formation of hydrothermal Mn concretions occurs in several steps. The initial step is the adsorption or precipitation of Mn, Si and Fe around siliceous remains of fossils and around cell wall of bacteria and extracellular polymers. These poorly crystallized phyllomanganates give rise to the formation of better crystallized birnessite and todorokite, which progressively increase in size and crystallinity. This study shows that biogenic and amorphous components of sediments provide reactive sites for precipitation of metallic elements and the formation of hydrothermal oxi-hydroxides in ridge flank environments. These minerals, which are good scavengers of metallic elements, must be taken into account when considering the water-rocks reactions controlling oceanic chemical budgets.

  10. Can comodulation masking release occur when frequency changes could promote perceptual segregation of the on-frequency and flanking bands?

    PubMed

    Verhey, Jesko L; Epp, Bastian; Stasiak, Arkadiusz; Winter, Ian M

    2013-01-01

    A common characteristic of natural sounds is that the level fluctuations in different frequency regions are coherent. The ability of the auditory system to use this comodulation is shown when a sinusoidal signal is masked by a masker centred at the signal frequency (on-frequency masker, OFM) and one or more off-frequency components, commonly referred to as flanking bands (FBs). In general, the threshold of the signal masked by comodulated masker components is lower than when masked by masker components with uncorrelated envelopes or in the presence of the OFM only. This effect is commonly referred to as comodulation masking release (CMR). The present study investigates if CMR is also observed for a sinusoidal signal embedded in the OFM when the centre frequencies of the FBs are swept over time with a sweep rate of one octave per second. Both a common change of different frequencies and comodulation could serve as cues to indicate which of the stimulus components originate from one source. If the common fate of frequency components is the stronger binding cue, the sweeping FBs and the OFM with a fixed centre frequency should no longer form one auditory object and the CMR should be abolished. However, psychoacoustical results with normal-hearing listeners show that a CMR is also observed with sweeping components. The results are consistent with the hypothesis of wideband inhibition as the underlying physiological mechanism, as the CMR should only depend on the spectral position of the flanking bands relative to the inhibitory areas (as seen in physiological recordings using stationary flanking bands). Preliminary physiological results in the cochlear nucleus of the Guinea pig show that a correlate of CMR can also be found at this level of the auditory pathway with sweeping flanking bands. PMID:23716254

  11. 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.

  12. 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

  13. Specialized chromatin structure domain boundary elements flanking a Drosophila heat shock gene locus are under torsional strain in vivo.

    PubMed

    Jupe, E R; Sinden, R R; Cartwright, I L

    1995-02-28

    An in vivo assay employing psoralen cross-linking was used to investigate the presence of unrestrained supercoiling in DNA sequences located in nontranscribed regions flanking the 3' ends of the pair of divergent heat shock protein 70 (hsp70) genes at locus 87A7 of Drosophila. Two of the regions examined contain sequences comprising the previously defined specialized chromatin structure elements (scs and scs'). Both of these putative chromosomal domain boundaries exhibited very similar levels of unrestrained negative supercoiling that remained high regardless of the transcriptional status of the hsp70 genes. The steric accessibility of the scs region before heat shock was 3-fold higher than either flanking region (consistent with its previously documented DNase I hypersensitivity); this increased an additional 2-fold following hsp70 gene activation without a concomitant rise in the accessibility of flanking regions. Most notably, a sequence which lies outside the presumed 87A7 domain, as defined by the centromere-proximal scs element, exhibited no detectable torsional tension regardless of gene activity in the domain. A sequence located just inside the scs region displayed a low level of tension that was also essentially unaffected by transcription, consistent with data obtained previously for a similarly situated fragment at the centromere-distal scs' location. The existence of a highly localized region of supercoiling within the scs and scs' sequences might be related to their activity in vivo as insulators of chromosomal position effects in Drosophila. PMID:7873544

  14. Conserved sequences in both coding and 5' flanking regions of mammalian opal suppressor tRNA genes.

    PubMed Central

    Pratt, K; Eden, F C; You, K H; O'Neill, V A; Hatfield, D

    1985-01-01

    The rabbit genome encodes an opal suppressor tRNA gene. The coding region is strictly conserved between the rabbit gene and the corresponding gene in the human genome. The rabbit opal suppressor gene contains the consensus sequence in the 3' internal control region but like the human and chicken genes, the rabbit 5' internal control region contains two additional nucleotides. The 5' flanking sequences of the rabbit and the human opal suppressor genes contain extensive regions of homology. A subset of these homologies is also present 5' to the chicken opal suppressor gene. Both the rabbit and the human genomes also encode a pseudogene. That of the rabbit lacks the 3' half of the coding region. Neither pseudogene has homologous regions to the 5' flanking regions of the genes. The presence of 5' homologies flanking only the transcribed genes and not the pseudogenes suggests that these regions may be regulatory control elements specifically involved in the expression of the eukaryotic opal suppressor gene. Moreover the strict conservation of coding sequences indicates functional importance for the opal suppressor tRNA genes. Images PMID:4022772

  15. 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.

  16. Linkage disequilibrium in the insulin gene region: size variation at the 5' flanking polymorphism and bimodality among "class I" alleles.

    PubMed Central

    McGinnis, R. E.; Spielman, R. S.

    1994-01-01

    The 5' flanking polymorphism (5'FP), a hypervariable region at the 5' end of the insulin gene, has "class 1" alleles (650-900 bp long) that are in positive linkage disequilibrium with insulin-dependent diabetes mellitus (IDDM). We report that precise sizing of the 5'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. We also examined 5'FP length variation in relation to allelic variation at nearby polymorphisms. At biallelic RFLPs on both sides of the 5'FP, we found that one allele exhibits near-total association with the upper component of the 5'FP class 1 distribution. Such associations represent a little-known but potentially widespread 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. PMID:7915880

  17. Qualitative and quantitative event-specific PCR detection methods for oxy-235 canola based on the 3' integration flanking sequence.

    PubMed

    Yang, Litao; Guo, Jinchao; Zhang, Haibo; Liu, Jia; Zhang, Dabing

    2008-03-26

    As more genetically modified plant events are approved for commercialization worldwide, the event-specific PCR method has become the key method for genetically modified organism (GMO) identification and quantification. This study reveals the 3' flanking sequence of the exogenous integration of Oxy-235 canola employing thermal asymmetric interlaced PCR (TAIL-PCR). On the basis of the revealed 3' flanking sequence, PCR primers and TaqMan probe were designed and qualitative and quantitative PCR assays were established for Oxy-235 canola. The specificity and limits of detection (LOD) and quantification (LOQ) of these two PCR assays were validated to as low as 0.1% for the relative LOD of qualitative PCR assay; the absolute LOD and LOQ were low to 10 and 20 copies of canola genomic DNA in quantitative PCR assay, respectively. Furthermore, ideal quantified results were obtained in the practical canola sample detection. All of the results indicate that the developed qualitative and quantitative PCR methods based on the revealed 3' integration flanking sequence are suitable for GM canola Oxy-235 identification and quantification.

  18. 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

  19. Developmentally regulated excision of a 28-base-pair sequence from the Paramecium genome requires flanking DNA.

    PubMed

    Ku, M; Mayer, K; Forney, J D

    2000-11-01

    The micronuclear DNA of Paramecium tetraurelia is estimated to contain over 50,000 short DNA elements that are precisely removed during the formation of the transcriptionally active macronucleus. Each internal eliminated sequence (IES) is bounded by 5'-TA-3' dinucleotide repeats, a feature common to some classes of DNA transposons. We have developed an in vivo assay to analyze these highly efficient and precise DNA excision events. The microinjection of a cloned IES into mating cells results in accurately spliced products, and the transformed cells maintain the injected DNA as extrachromosomal molecules. A series of deletions flanking one side of a 28-bp IES were constructed and analyzed with the in vivo assay. Whereas 72 bp of DNA flanking the eliminated region is sufficient for excision, lengths of 31 and 18 bp result in reduced excision and removal of all wild-type sequences adjacent to the TA results in complete failure of excision. In contrast, nucleotide mutations within the middle of the 28-bp IES do not prevent excision. The results are consistent with a functional role for perfect inverted repeats flanking the IES. PMID:11046136

  20. Lithospheric structure of the eastern flank of the Rio Grande Rift via receiver function velocity analysis

    NASA Astrophysics Data System (ADS)

    Agrawal, M.; Pulliam, J.; Sen, M. K.; Grand, S.

    2015-12-01

    To better delineate a seismic anomaly beneath the eastern flank of the Rio Grande Rift identified by seismic tomography, we depth-migrated Ps and Sp receiver functions using data from the SIEDCAR (Seismic Investigation of Edge Driven Convection Association with Rio Grande Rift) and USArray Transportable Array (TA) deployments. We performed Common Conversion Point (CCP) stacking to improve the S/N ratio of receiver functions. Using an incorrect velocity model for depth migration of a stacked CCP image may generate an inaccurate picture of the subsurface. To find sufficiently accurate P- and S-velocity models for migration, we optimize the average correlation value of common receiver gathers for target features - in this case the Moho and the LAB - while perturbing the shear wave velocities in a process driven by simulated annealing. The technique simultaneously finds depths to major discontinuities (in this case the Moho and LAB) and S and P velocity profiles beneath each seismic station in a manner that is similar to velocity analysis in reflection seismology. An application to data acquired in southeastern New Mexico and west Texas, at an average station spacing of 35 km, reveals an abrupt increase in lithospheric thickness from west to east, from the Rio Grande Rift to the Great Plains craton. Previous studies found an elongated high velocity anomaly that extends to depths approaching 500 km in southeastern New Mexico and west Texas that is distinct from the thick Great Plains lithosphere. Our stacked 3-D image confirms the anomaly's existence and shows that it is more laterally extensive than was previously indicated. Recent numerical modeling suggests that an abrupt change in lithospheric thickness, which creates a step change in densities, may produce a gravitational instability that leads to thicker mantle lithosphere dripping off into the lower density asthenosphere. As the mantle deforms it alternately thickens and thins the crust, producing topographic

  1. 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

  2. Comodulation Masking Release Determined in the Mouse (Mus musculus) using a Flanking-band Paradigm

    PubMed Central

    Klink, Karin B.; Dierker, Holger; Beutelmann, Rainer

    2009-01-01

    Comodulation masking release (CMR) has been attributed to auditory processing within one auditory channel (within-channel cues) and/or across several auditory channels (across-channel cues). The present flanking-band (FB) experiment—using a 25-Hz-wide on-frequency noise masker (OFM) centered at the signal frequency of 10 kHz and a single 25-Hz-wide noise FB—was designed to separate the amount of CMR due to within- and across-channel cues and to investigate the role of temporal cues on the size of within-channel CMR. The results demonstrated within-channel CMR in the Naval Medical Research Institute mouse, while no unambiguous evidence could be found for CMR occurring due to across-channel processing (i.e., “true CMR”). The amount of within-channel CMR was dependent on the frequency separation between the FB and the OFM. CMR increased from 4 to 6 dB for a frequency separation of 1 kHz to 18 dB for a frequency separation of 100 Hz. The large increase for a frequency separation of 100 Hz is likely to be due to the exploitation of changes in the temporal pattern of the stimulus upon the addition of the signal. Temporal interaction between both masker bands results in modulations with a large depth at a modulation frequency equal to the beating rate. Adding a signal to the maskers reduces the depth of the modulation. The auditory system of mice might be able to use the change in modulation depth at a beating frequency of 100 Hz as a cue for signal detection, while being unable to detect changes in modulation depth at high modulation frequencies. These results are consistent with other experiments and model predictions for CMR in humans which suggested that the main contribution to the CMR effect stems from processing of within-channel cues. PMID:19763691

  3. 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.

  4. 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

  5. Early Tertiary exhumation of the flank of a forearc basin, southwest Talkeetna Mountains, Alaska

    USGS Publications Warehouse

    Bleick, Heather A.; Till, Alison B.; Bradley, Dwight C.; O’Sullivan, Paul; Wooden, Joe L.; Bradley, Dan B.; Taylor, Theresa A.; Friedman, Sam B.; Hults, Chad P.

    2012-01-01

    New geochronologic and thermochronologic data from rocks near Hatcher Pass, southwest Talkeetna Mountains, Alaska, record earliest Paleocene erosional and structural exhumation on the flank of the active Cook Inlet forearc basin. Cretaceous plutons shed sediments to the south, forming the Paleocene Arkose Ridge Formation. A Paleocene(?)-Eocene detachment fault juxtaposed ~60 Ma metamorphic rocks with the base of the Arkose Ridge Formation. U-Pb (analyzed by Sensitive High Resolution Ion Micro Probe Reverse Geometry (SHRIMP-RG)) zircon ages of the Cretaceous plutons, more diverse than previously documented, are 90.3±0.3 (previously considered a Jurassic unit), 79.1±1.0, 76.1±0.9, 75.8±0.7, 72.5±0.4, 71.9±0.3, 70.5±0.2, and 67.3±0.2 Ma. The cooling of these plutons occurred between 72 and 66 Ma (zircon fission track (FT) closure ~225°C). 40Ar/39Ar analyses of hornblende, white mica, and biotite fall into this range (Harlan and others, 2003). New apatite FT data collected on a west-to-east transect reveal sequential exhumation of fault blocks at 62.8±2.9, 54±2.5, 52.6±2.8, and 44.4±2.2 Ma. Plutonic clasts accumulated in the Paleocene Arkose Ridge Formation to the south. Detrital zircon (DZ) ages from the formation reflect this provenance: a new sample yielded one grain at 61 Ma, a dominant peak at 76 Ma, and minor peaks at 70, 80, 88, and 92 Ma. The oldest zircon is 181 Ma. Our apatite FT ages range from 35.1 to 50.9 Ma. Greenschist facies rocks now sit structurally between the plutonic rocks and the Arkose Ridge Formation. They are separated from plutonic rocks by the vertical Hatcher Pass fault and from the sedimentary rocks by a detachment fault. Ar cooling ages (Harlan and others, 2003) and new zircon FT ages for these rocks are concordant at 61-57 Ma, synchronous with deposition of the Arkose Ridge Formation. A cooling age of ~46 Ma came from one apatite FT sample. The metamorphic protolith (previously considered Jurassic) was deposited at or after

  6. 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

  7. Growth and collapse of Waianae Volcano, Hawaii, as revealed by exploration of its submarine flanks

    NASA Astrophysics Data System (ADS)

    Coombs, Michelle L.; Clague, David A.; Moore, Gregory F.; Cousens, Brian L.

    2004-08-01

    Wai`anae Volcano comprises the western half of O`ahu Island, but until recently little was known about the submarine portion of this volcano. Seven new submersible dives, conducted in 2001 and 2002, and multibeam bathymetry offshore of Wai`anae provide evidence pertaining to the overall growth of the volcano's edifice as well as the timing of collapses that formed the Wai`anae slump complex. A prominent slope break at ˜1400 mbsl marks the paleoshoreline of Wai`anae at the end of its shield-building stage and wraps around Ka`ena Ridge, suggesting that this may have been an extension of Wai`anae's northwest rift zone. Subaerially erupted tholeiitic lavas were collected from a small shield along the crest of Ka`ena Ridge. The length of Wai`anae's south rift zone is poorly constrained but reaches at least 65 km on the basis of recovered tholeiite pillows at this distance from the volcano's center. Wai`anae's growth was marked by multiple collapse and deformation events during and after its shield stage, resulting in the compound mass wasting features on the volcano's southwest flank (Wai`anae slump complex). The slump complex, one of the largest in Hawai`i, covering an area of ˜5500 km2, is composed of several distinct sections on the basis of morphology and the lithologies of recovered samples. Two dives ascended the outer bench of the slump complex and collected predominantly low-S tholeiites that correlate with subaerial lavas erupted early during the volcano's shield stage, from 3.9 to 3.5 Ma. Pillow lavas from the outer bench have Pb, Sr, and Nd isotopic values that overlap with previously published subaerial Wai`anae lavas. On the basis of the compositions of the recovered samples, the main body of the slump complex, as represented by the outer bench, probably formed during and shortly after the early shield stage. To the southwest of the outer bench lies a broad debris field on the seafloor, interpreted to have formed by a catastrophic collapse event that

  8. 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.

  9. 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

  10. 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

  11. Microbial communities at the borehole observatory on the Costa Rica Rift flank (Ocean Drilling Program Hole 896A).

    PubMed

    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.

  12. 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.

  13. 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.

  14. Comparison of orthologous and paralogous DNA flanking the wheat high molecular weight glutenin genes: sequence conservation and divergence, transposon distribution, and matrix-attachment regions.

    PubMed

    Anderson, O D; Larka, L; Christoffers, M J; McCue, K F; Gustafson, J P

    2002-04-01

    Extended flanking DNA sequences were characterized for five members of the wheat high molecular weight (HMW) glutenin gene family to understand more of the structure, control, and evolution of these genes. Analysis revealed more sequence conservation among orthologous regions than between paralogous regions, with differences mainly owing to transposition events involving putative retrotransposons and several miniature inverted transposable elements (MITEs). Both gyspy-like long terminal repeat (LTR) and non-LTR retrotransposon sequences are represented in the flanking DNAs. One of the MITEs is a novel class, but another MITE is related to the maize Stowaway family and is widely represented in Triticeae express sequence tags (ESTs). Flanking DNA of the longest sequence, a 20 425-bp fragment including and surrounding the HMW-glutenin Bx7 gene, showed additional cereal gene-like sequences both immediately 5' and 3' to the HMW-glutenin coding region. The transcriptional activities of sequences related to these flanking putative genes and the retrotransposon-related regions were indicated by matches to wheat and other Triticeae ESTs. Predictive analysis of matrix-attachment regions (MARs) of the HMW glutenin and several alpha-, gamma-, and omega-gliadin flanking DNAs indicate potential MARs immediately flanking each of the genes. Matrix binding activity in the predicted regions was confirmed for two of the HMW-glutenin genes.

  15. 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.

  16. 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

  17. 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

  18. 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

  19. A 66-bp deletion in growth hormone releasing hormone gene 5'-flanking region with largemouth bass recessive embryonic lethal.

    PubMed

    Ma, D M; Han, L Q; Bai, J J; Li, S J; Fan, J J; Yu, L Y; Quan, Y C

    2014-06-01

    Growth hormone releasing hormone (GHRH) regulates the secretion of growth hormone (GH) in the pituitary gland. A 66-bp deletion (c.-923_-858del) was detected in the 5'-flanking sequence of the largemouth bass (Micropterus salmoides) GHRH gene. In two cultured random populations of adult individuals (A: n = 170 and B: n = 150), the genotype ratios of +/+:+/- were 2.5:1 and 2.8:1 respectively. Only one -/- fish was detected. A Largemouth bass family was constructed with two heterozygous individuals (+/-) as parents. The genotype ratio of +/+:+/-:-/- in the filial generation embryos was 1:1.6:0.1 at the neurula and 1:2:0 at hatched larvae stages. This indicated that the 66-bp deletion was a recessive lethal site and that homozygous individuals (-/-) died off in embryonic development. The growth traits (body weight, body length and body depth) were measured, and the GHRH mRNA expression levels in brain tissue were detected using real-time PCR. The effects of genotype (+/-) on growth traits and GHRH mRNA expression were not significant. Although the cause of death was not clear, the results hint that the 66-bp deletion site in GHRH 5'-flanking sequence significantly affects the livability in largemouth bass embryonic development. PMID:24697798

  20. A 66-bp deletion in growth hormone releasing hormone gene 5'-flanking region with largemouth bass recessive embryonic lethal.

    PubMed

    Ma, D M; Han, L Q; Bai, J J; Li, S J; Fan, J J; Yu, L Y; Quan, Y C

    2014-06-01

    Growth hormone releasing hormone (GHRH) regulates the secretion of growth hormone (GH) in the pituitary gland. A 66-bp deletion (c.-923_-858del) was detected in the 5'-flanking sequence of the largemouth bass (Micropterus salmoides) GHRH gene. In two cultured random populations of adult individuals (A: n = 170 and B: n = 150), the genotype ratios of +/+:+/- were 2.5:1 and 2.8:1 respectively. Only one -/- fish was detected. A Largemouth bass family was constructed with two heterozygous individuals (+/-) as parents. The genotype ratio of +/+:+/-:-/- in the filial generation embryos was 1:1.6:0.1 at the neurula and 1:2:0 at hatched larvae stages. This indicated that the 66-bp deletion was a recessive lethal site and that homozygous individuals (-/-) died off in embryonic development. The growth traits (body weight, body length and body depth) were measured, and the GHRH mRNA expression levels in brain tissue were detected using real-time PCR. The effects of genotype (+/-) on growth traits and GHRH mRNA expression were not significant. Although the cause of death was not clear, the results hint that the 66-bp deletion site in GHRH 5'-flanking sequence significantly affects the livability in largemouth bass embryonic development.

  1. Comparative analysis on the structural features of the 5' flanking region of kappa-casein genes from six different species.

    PubMed

    Gerencsér, Akos; Barta, Endre; Boa, Simon; Kastanis, Petros; Bösze, Zsuzsanna; Whitelaw, C Bruce A

    2002-01-01

    Kappa-casein plays an essential role in the formation, stabilisation and aggregation of milk micelles. Control of kappa-casein expression reflects this essential role, although an understanding of the mechanisms involved lags behind that of the other milk protein genes. We determined the 5'-flanking sequences for the murine, rabbit and human kappa-casein genes and compared them to the published ruminant sequences. The most conserved region was not the proximal promoter region but an approximately 400 bp long region centred 800 bp upstream of the TATA box. This region contained two highly conserved MGF/STAT5 sites with common spacing relative to each other. In this region, six conserved short stretches of similarity were also found which did not correspond to known transcription factor consensus sites. On the contrary to ruminant and human 5' regulatory sequences, the rabbit and murine 5'-flanking regions did not harbour any kind of repetitive elements. We generated a phylogenetic tree of the six species based on multiple alignment of the kappa-casein sequences. This study identified conserved candidate transcriptional regulatory elements within the kappa-casein gene promoter.

  2. Multispacecraft study on the dynamics of the dusk-flank magnetosphere under northward IMF: 10-11 January 1997

    NASA Astrophysics Data System (ADS)

    Stenuit, H.; Fujimoto, M.; Fuselier, S. A.; Sauvaud, J.-A.; Wing, S.; Fedorov, A.; Budnik, E.; Savin, S. P.; Trattner, K. J.; Angelopoulos, V.; Bonnell, J.; Phan, T. D.; Mukai, T.; Pedersen, A.

    2002-10-01

    The latter half of the magnetic cloud event on 10-11 January 1997 is studied in the context of the cold-dense plasma sheet. A fortuitous distribution of spacecraft in key regions allows us to relate the plasma sheet status transition with the boundary layer process. When the interplanetary magnetic field (IMF) was strongly northward and the solar wind density returned to a nominal value from an anomalously large one, two spacecraft, Geotail and Interball-Tail, were in the dusk-flank region and detected a change in the plasma sheet status from hot and tenuous to cold and dense. The change seen by these spacecraft making in situ observations is confirmed to be a global feature by DMSP observations at low altitude. Just around this time, Interball-Aurora and Polar were crossing the dusk-auroral oval, monitoring globally the dynamics of the dusk-flank magnetopause at its footpoint. Injection of magnetosheath-like ions was detected by these spacecraft. We try to relate these observations with the processes that transport the magnetosheath plasma onto the magnetospheric field lines. Three candidate processes are discussed, but none of them turn out to be convincing, indicating the need for further study on this issue.

  3. Petroleum system of the sourth-eastern portion of the Maracaibo basin: Ceuta-North Andean Flank

    SciTech Connect

    Marcano, F.; Boesi, T.; Pirela, B.; Alcala, L.; Violino, R.

    1996-08-01

    The South Eastern portion of the Maracaibo basin encompasses a giant field (Ceuta) that carries ultimate recoverable oil reserves of more than 2.5 billion barrels and areas with little or no drilling. Oil in the area has been found in Cretaceous and Tertiary sediments and, in seeps along the North Andean Flank, where oil-source rock correlation based on biomarker fingerprints relates the existing crude to the Cretaceous La Luna source rock. A main tectonic constituent of the area is represented by the Merida arch, controlling the sedimentation until the end of the Cretaceous passive margin. Also, the Middle Eocone rifting and its associated structures have determined important thickness variations of deltaic eocene prograding sediments. A significant sequence boundary is associated to compression, uplifting, erosion or non deposition from the late Eocene to the early Miocene. A gradual tilting towards the southeast developed as a consequence of the Andean foredeep in the southern area. Heat flow field is found to be different from one area to another, as given by estimations taking into account well temperature measurements, rock maturity and the calculation of thermal conductivities of the rock formations as a function of their lithologies, porosities and temperature. Kinetic modelling of the hydrocarbon generation indicates a complex history starting in the northeastern area during the Eocene with the generation of oil and still ongoing nowadays in the north Andean Flank with the generation of gas.

  4. Ability of a Bacterial Chromosome Segment to Invert Is Dictated by Included Material Rather than Flanking Sequence

    PubMed Central

    Mahan, M. J.; Roth, J. R.

    1991-01-01

    Homologous recombination between sequences present in inverse order within the same chromosome can result in inversion formation. We have previously shown that inverse order sequences at some sites (permissive) recombine to generate the expected inversion; no inversions are found when the same inverse order sequences flank other (nonpermissive) regions of the chromosome. In hopes of defining how permissive and nonpermissive intervals are determined, we have constructed a strain that carries a large chromosomal inversion. Using this inversion mutant as the parent strain, we have determined the ``permissivity'' of a series of chromosomal sites for secondary inversions. For the set of intervals tested, permissivity seems to be dictated by the nature of the genetic material present within the chromosomal interval being tested rather than the flanking sequences or orientation of this material in the chromosome. Almost all permissive intervals include the origin or terminus of replication. We suggest that the rules for recovery of inversions reflect mechanistic restrictions on the occurrence of inversions rather than lethal consequences of the completed rearrangement. PMID:1783289

  5. 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.

  6. 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

  7. TM6, a novel nuclear matrix attachment region, enhances its flanking gene expression through influencing their chromatin structure.

    PubMed

    Ji, Lusha; Xu, Rui; Lu, Longtao; Zhang, Jiedao; Yang, Guodong; Huang, Jinguang; Wu, Changai; Zheng, Chengchao

    2013-08-01

    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.

  8. 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

  9. TM6, a novel nuclear matrix attachment region, enhances its flanking gene expression through influencing their chromatin structure.

    PubMed

    Ji, Lusha; Xu, Rui; Lu, Longtao; Zhang, Jiedao; Yang, Guodong; Huang, Jinguang; Wu, Changai; Zheng, Chengchao

    2013-08-01

    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

  10. Cloning, sequencing, and functional analysis of the 5'-flanking region of the rat 3 alpha-hydroxysteroid/dihydrodiol dehydrogenase gene.

    PubMed

    Lin, H K; Penning, T M

    1995-09-15

    Rat liver 3 alpha-hydroxysteroid/dihydrodiol dehydrogenase (3 alpha-HSD/DD) is a member of the aldo-keto reductase gene superfamily. It displays high constitutive expression and inactivates circulating steroid hormones and suppresses the formation of polycyclic aromatic hydrocarbon anti- and syn-diol-epoxides (ultimate carcinogens). To elucidate mechanisms responsible for constitutive expression of the 3 alpha-HSD/DD gene a rat genomic library obtained from adult Sprague-Dawley female liver (HaeIII partial digest) was screened, using a probe corresponding to the 5'-end of the cDNA (-15 to +250), and a 15.8-kb genomic clone was isolated. Sequencing revealed that 6.3 kb contained exon 1 (+16 to +138 bp) plus additional introns and exons. The transcription start site (+1) was located by primer extension analysis, and the initiation codon, ATG, was located at +55 bp. The remaining 9.5 kb represented the 5'-flanking region of the rat 3 alpha-HSD/DD gene. A 1.6-kb fragment of this region was sequenced. A TATTTAA sequence (TATA box) was found at 33 bp upstream from the major transcription start site. cis-acting elements responsible for the constitutive expression of the rat 3 alpha-HSD/DD gene were located on the 5'-flanking region by transient transfection of reporter-gene (chloramphenicol acetyl transferase, CAT) constructs into human hepatoma cells (HepG2). CAT assays identified the basal promoter between (-199 and +55 bp), the presence of a proximal enhancer (-498 to -199 bp) which stimulated CAT activity 6-fold, the existence of a powerful silencer (-755 to -498 bp), and a strong distal enhancer (-4.0 to -2.0 kb) which increased CAT activity by 20-40-fold. A computer search of available consensus sequences for trans-acting factors revealed that a cluster of Oct-sites were uniquely located in the silencer region. Using the negative response element (-797 to -498 bp) as a probe and nuclear extracts from HepG2 cells, three bands were identified by gel mobility shift

  11. 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

  12. 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.

  13. 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

  14. Analysis of the role of 5' and 3' flanking sequence elements upon in vivo expression of the plant tRNATrp genes.

    PubMed Central

    Ulmasov, B; Folk, W

    1995-01-01

    We have isolated the majority (seven) of the tRNA(Trp) genes of Arabidopsis and have studied the 5' and 3' flanking sequence requirements for their efficient expression in vivo by using an assay requiring translational suppression of the luciferase reporter gene. The expressed tRNA(Trp) genes contain no highly conserved 5' flanking sequences; however, these sequences are distinctly AT rich, contain several possible TATA elements, and are bound in vitro by recombinant plant TATA binding protein. Replacement of the natural 5' flanking sequences with three different sequences lacking TATA elements reduced expression in vivo up to 10-fold; the same effect was observed when the TATA elements of the natural 5' sequences were inactivated by point mutations. Introduction of a single TATA element from the adenovirus major late promoter into an artificial 5' flanking region of the tRNA(Trp) gene enhanced expression in vivo when the TATA element was placed at position -32 relative to the first nucleotide of the mature tRNA sequence, but not when it was placed at position -24. Primer extension analyses of in vitro transcripts revealed that the position of the TATA element helps dictate the start site of transcription. Efficient expression of the tRNA genes in vivo also required 3' flanking sequences capable of terminating transcription. PMID:7580260

  15. 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

  16. 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.

  17. [Distant interactions between enhancers and promoters in Drosophila melanogaster are mediated by transgene-flanking Su(Hw) insulators].

    PubMed

    Davydova, A I; Erokhin, M M; Georgiev, P G; Chetverina, D A

    2011-08-01

    Insulators are DNA elements modulating gene activation by enhancers. Interaction between insulators can result in either isolation, or activation of promoter by the enhancer. In the present study, it is demonstrated that in transgenic lines, the yellow enhancers are unable to activate promoter of the tagged gene through the mini-white gene. The mini-white promoter, which functions as an insulator, can block the enhancer activity. In case that the genes and regulatory elements in the construct are flanked by Su(Hw) insulators from retroposon MDG4, interaction between enhancers and the yellow promoter is restored. The data obtained are congruent with the model suggesting that promoters can function as insulators, and that interaction between the insulators facilitates the interaction between enhancers and promoters within transcriptional domain.

  18. Characterization and nucleotide sequence of a chicken gene encoding an opal suppressor tRNA and its flanking DNA segments.

    PubMed Central

    Hatfield, D L; Dudock, B S; Eden, F C

    1983-01-01

    A naturally occurring opal suppressor serine tRNA has been purified from chicken liver and used as a probe to isolate the corresponding gene from a library of chicken DNA in bacteriophage lambda. This minor tRNA is encoded by a single-copy gene that is not part of a tRNA gene cluster. DNA sequence analysis of the gene and its flanking DNA segments shows that the gene is encoded in an 87-base-pair segment without intervening sequences and specifies a tRNA that reads the termination codon UGA. This gene has additional nucleotides in the 5' internal promoter region but has a normal 3' internal promoter sequence and the usual termination signal. Images PMID:6308662

  19. 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

  20. The 5' flanking region of a barley B hordein gene controls tissue and developmental specific CAT expression in tobacco plants.

    PubMed

    Marris, C; Gallois, P; Copley, J; Kreis, M

    1988-07-01

    The 549 base pairs of the 5' flanking region of a barley seed storage protein (B1 hordein) gene were linked to the reporter gene encoding chloramphenicol acetyl transferase (CAT). The chimaeric gene was transferred into tobacco plants using Agrobacterium tumefaciens. CAT enzyme activity was detected in the seeds, but not in the leaves, of the transgenic plants. Furthermore, enzyme activity was found only in the endosperm, and only from fifteen days after pollination. In contrast, the constitutive 19S promoter from cauliflower mosaic virus (CaMV) directed the expression of the CAT gene in the leaves as well as in both the endosperm and embryo and at all stages in seed development.

  1. Geomechanical parameters of intact rocks and rock masses from the Canary Islands: Implications on their flank stability

    NASA Astrophysics Data System (ADS)

    Rodríguez-Losada, J. A.; Hernández-Gutiérrez, L. E.; Olalla, C.; Perucho, A.; Serrano, A.; Eff-Darwich, A.

    2009-05-01

    New data on the geomechanical properties of the highly cohesive volcanic rocks of the Canary Archipelago and their role in the flank stability on oceanic islands are provided in this work. On the basis of the textural and petrological features, a preliminary classification of rocks, grouped into lithotypes, was carried out. This classification includes vesicular and non vesicular basalts, trachybasalts, trachytes, phonolites, welded and non welded ignimbrites. Strength and strain-related features are summarized here for each distinctive lithotype. Taking into account the results of the uniaxial and triaxial compressive tests, the geological strength index of rock masses and their textural-structural features, an estimate of the rock mass parameters and Mohr-Coulomb fit has been carried out. A final discussion on the impact of those geomechanical parameters as factors governing the stability of steep slopes in volcanic islands is then made here as a contribution in volcanic risk.

  2. Sequence-specific flexibility organization of splicing flanking sequence and prediction of splice sites in the human genome.

    PubMed

    Zuo, Yongchun; Zhang, Pengfei; Liu, Li; Li, Tao; Peng, Yong; Li, Guangpeng; Li, Qianzhong

    2014-09-01

    More and more reported results of nucleosome positioning and histone modifications showed that DNA structure play a well-established role in splicing. In this study, a set of DNA geometric flexibility parameters originated from molecular dynamics (MD) simulations were introduced to discuss the structure organization around splice sites at the DNA level. The obtained profiles of specific flexibility/stiffness around splice sites indicated that the DNA physical-geometry deformation could be used as an alternative way to describe the splicing junction region. In combination with structural flexibility as discriminatory parameter, we developed a hybrid computational model for predicting potential splicing sites. And the better prediction performance was achieved when the benchmark dataset evaluated. Our results showed that the mechanical deformability character of a splice junction is closely correlated with both the splice site strength and structural information in its flanking sequences.

  3. 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.

  4. Cyclic Explosivity in High Elevation Phreatomagmatic Eruptions at Ocean Island Volcanoes: Implications for Aquifer Pressurization and Volcano Flank Destabilization.

    NASA Astrophysics Data System (ADS)

    Tarff, R.; Day, S. J.; Downes, H.; Seghedi, I.

    2015-12-01

    Groundwater heating and pressurization of aquifers trapped between dikes in ocean island volcanoes has been proposed as a mechanism for destabilizing and triggering large-volume flank collapses. Previous modelling has indicated that heat transfer from sustained magma flow through dikes during eruption has the potential to produce destabilizing levels of pressure on time scales of 4 to 400 days, if the aquifers remain confined. Here we revisit this proposal from a different perspective. We examine evidence for pressure variations in dike-confined aquifers during eruptions at high elevation vents on ocean island volcanoes. Initially magmatic, these eruptions change to mostly small-volume explosive phreatomagmatic activity. A recent example is the 1949 eruption on La Palma, Canary Islands. Some such eruptions involve sequences of larger-volume explosive phases or cycles, including production of voluminous low-temperature, pyroclastic density currents (PDC). Here we present and interpret data from the Cova de Paul crater eruption (Santo Antao, Cape Verde Islands). The phreatomagmatic part of this eruption formed two cycles, each culminating with eruption of PDCs. Compositional and textural variations in the products of both cycles indicate that the diatreme fill began as coarse-grained and permeable which allowed gas to escape. During the eruption, the fill evolved to a finer grained, poorly sorted, less permeable material, in which pore fluid pressures built up to produce violent explosive phases. This implies that aquifers adjacent to the feeder intrusion were not simply depressurized at the onset of phreatomagmatic explosivity but experienced fluctuations in pressure throughout the eruption as the vent repeatedly choked and emptied. In combination with fluctuations in magma supply rate, driving of aquifer pressurization by cyclical vent choking will further complicate the prediction of flank destabilization during comparable eruptions on ocean island volcanoes.

  5. 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.

  6. Retroposed elements and their flanking regions resolve the evolutionary history of xenarthran mammals (armadillos, anteaters, and sloths).

    PubMed

    Möller-Krull, Maren; Delsuc, Frédéric; Churakov, Gennady; Marker, Claudia; Superina, Mariella; Brosius, Jürgen; Douzery, Emmanuel J P; Schmitz, Jürgen

    2007-11-01

    Armadillos, anteaters, and sloths (Order Xenarthra) comprise 1 of the 4 major clades of placental mammals. Isolated in South America from the other continental landmasses, xenarthrans diverged over a period of about 65 Myr, leaving more than 200 extinct genera and only 31 living species. The presence of both ancestral and highly derived anatomical features has made morphoanatomical analyses of the xenarthran evolutionary history difficult, and previous molecular analyses failed to resolve the relationships within armadillo subfamilies. We investigated the presence/absence patterns of retroposons from approximately 7,400 genomic loci, identifying 35 phylogenetically informative elements and an additional 39 informative rare genomic changes (RGCs). DAS-short interspersed elements (SINEs), previously described only in the Dasypus novemcinctus genome, were found in all living armadillo genera, including the previously unsampled Chlamyphorus, but were noticeably absent in sloths. The presence/absence patterns of the phylogenetically informative retroposed elements and other RGCs were then compared with data from the DNA sequences of the more than 12-kb flanking regions of these retroposons. Together, these data provide the first fully resolved genus tree of xenarthrans. Interestingly, multiple evidence supports the grouping of Chaetophractus and Zaedyus as a sister group to Euphractus within Euphractinae, an association that was not previously demonstrated. Also, flanking sequence analyses favor a close phylogenetic relationship between Cabassous and Tolypeutes within Tolypeutinae. Finally, the phylogenetic position of the subfamily Chlamyphorinae is resolved by the noncoding sequence data set as the sister group of Tolypeutinae. The data provide a stable phylogenetic framework for further evolutionary investigations of xenarthrans and important information for defining conservation priorities to save the diversity of one of the most curious groups of mammals.

  7. 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.

  8. 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

  9. Polymorphisms in the HSP90AA1 5' flanking region are associated with scrapie incubation period in sheep.

    PubMed

    Marcos-Carcavilla, Ane; Moreno, Carole; Serrano, Magdalena; Laurent, Pascal; Cribiu, Edmond P; Andréoletti, Olivier; Ruesche, Julien; Weisbecker, Jean-Louis; Calvo, Jorge H; Moazami-Goudarzi, Katayoun

    2010-07-01

    Susceptibility to scrapie is mainly controlled by point mutations at the PRNP locus. However, additional quantitative trait loci (QTL) have been identified across the genome including a region in OAR18. The gene which encodes the inducible form of the cytoplasmic Hsp90 chaperone (HSP90AA1) maps within this region and seems to be associated with the resistance/susceptibility to scrapie in sheep. Here, we have analyzed several polymorphisms which were previously described in the ovine HSP90AA1 5' flanking region and in intron 10 in two naturally scrapie infected Romanov sheep populations. First, we have studied 58 ARQ/VRQ animals pertaining to the sire family where the QTL influencing scrapie incubation period in OAR18 was detected. We have found a significant association between polymorphisms localized at -660 and -528 in the HSP90AA1 5' flanking region and the scrapie incubation period. These two polymorphisms have also been studied in a second sample constituted by 62 VRQ/VRQ sheep showing an extreme incubation period. Results are concordant with the first dataset. Finally, we have studied the HSP90AA1 expression in scrapie and control animals (N = 41) with different HSP90AA1 genotypes by real time PCR on blood samples. The HSP90AA1 expression rate was equivalent in CC(-600)AA(-528) and CG(-600)AG(-528) scrapie resistant animals (ARR/ARR) and was higher in their CC(-600)AA(-528) than in their CG(-600)AG(-528) scrapie susceptible counterparts (VRQ/VRQ). Our results support the hypothesis that the ovine HSP90AA1 gene acts as a modulator of scrapie susceptibility, contributing to the observed differences in the incubation period of scrapie infected animals with the same PRNP genotype.

  10. 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.

  11. 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).

  12. High similarity between flanking regions of different microsatellites detected within each of two species of Lepidoptera: Parnassius apollo and Euphydryas aurinia.

    PubMed

    Meglecz, Emese; Petenian, Frederic; Danchin, Etienne; D'Acier, Armelle Coeur; Rasplus, Jean-Yves; Faure, Eric

    2004-06-01

    Microsatellite flanking regions have been compared in two butterfly species. Several microsatellite flanking regions showed high similarity to one another among different microsatellites within a same species, but very few similarities were found between species. This can be the consequence of either duplication/multiplication events involving large regions containing microsatellites or of microsatellites imbedded in minisatellite regions. The multiplication of microsatellites might also be linked to mobile elements. Furthermore, crossing over between nonhomologous microsatellites can lead to the exchange of the flanking regions between microsatellites. The same phenomenon was observed in both studied butterfly species but not in Aphis fabae (Hemiptera), which was screened at the same time using the same protocol. These findings might explain, at least partially, why microsatellite isolation in Lepidoptera has been relatively unsuccessful so far.

  13. 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

  14. 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.

  15. 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

  16. 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

  17. 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

  18. Leakage of Active Crater lake brine through the north flank at Rincón de la Vieja volcano, northwest Costa Rica, and implications for crater collapse

    NASA Astrophysics Data System (ADS)

    Kempter, K. A.; Rowe, G. L.

    2000-04-01

    The Active Crater at Rincón 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 Rincón 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 Rincón 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

  19. 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

  20. 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

  1. 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

  2. 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

  3. 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

  4. Flank collapse at Mount Wrangell, Alaska, recorded by volcanic mass-flow deposits in the Copper River lowland

    USGS Publications Warehouse

    Waythomas, C.F.; Wallace, K.L.

    2002-01-01

    An areally extensive volcanic mass-flow deposit of Pleistocene age, known as the Chetaslina volcanic mass-flow deposit, is a prominent and visually striking deposit in the southeastern Copper River lowland of south-central Alaska. The mass-flow deposit consists of a diverse mixture of colorful, variably altered volcanic rocks, lahar deposits, glaciolacustrine diamicton, and till that record a major flank collapse on the southwest flank of Mount Wrangell. The deposit is well exposed near its presumed source, and thick, continuous, stratigraphic exposures have permitted us to study its sedimentary characteristics as a means of better understanding the origin, significance, and evolution of the deposit. Deposits of the Chetaslina volcanic mass flow in the Chetaslina River drainage are primary debris-avalanche deposits and consist of two principal facies types, a near-source block facies and a distal mixed facies. The block facies is composed entirely of block-supported, shattered and fractured blocks with individual blocks up to 40 m in diameter. The mixed facies consists of block-sized particles in a matrix of poorly sorted rock rubble, sand, and silt generated by the comminution of larger blocks. Deposits of the Chetaslina volcanic mass flow exposed along the Copper, Tonsina, and Chitina rivers are debris-flow deposits that evolved from the debris-avalanche component of the flow and from erosion and entrainment of local glacial and glaciolacustrine diamicton in the Copper River lowland. The debris-flow deposits were probably generated through mixing of the distal debris avalanche with the ancestral Copper River, or through breaching of a debris-avalanche dam across the ancestral river. The distribution of facies types and major-element chemistry of clasts in the deposit indicate that its source was an ancestral volcanic edifice, informally known as the Chetaslina vent, on the southwest side of Mount Wrangell. A major sector collapse of the Chetaslina vent initiated

  5. Controls on erosional retreat of the uplifted rift flanks at the Gulf of Suez and northern Red Sea

    NASA Technical Reports Server (NTRS)

    Steckler, Michael S.; Omar, Gomaa I.

    1994-01-01

    The Gulf of Suez and the Red Sea rigts are currently bordered by large asymmetric uplifts that are undergoing erosion. We find that the amount and timing of erosion vary systematically along the strike of the margin and have been controlled by variations in the perift stratigraphy. The perfit strata are compsoed of cliff-forming Eocene-Cretaceous carbonates overlaying the easily eroded Cretaceous-Cambrian 'Nubian' sandstone. This lithologic succession promotes scarp retreat of the sedimentary section, follwed by dissection of the underlying basement. The perift section thins from over 2000 m at the northern end of the rift to less htan 400 m at its junction with the Red Sea. Thus, at the northern part of the Gulf of Suez, the Nubian sandstone is minimally exposed, and the carbonates form a scarp at the rift border fault. Farther south, undercuttin of hte carbonates by erosion of the sandstion has resulted in scarp retreat. The escarpment cuts diagonally away from the border fault andis over 100 km inland from the border fault at the southernmost Gulf of Suez. The amount of retreat varies inversely with the sediment thickness. Exposure and erosion of basement are initiated by the retreate of the escarpment, and the depth of erosion, as indicated by fission track ages, increases with distance from the escarpment. These observations are explained by a model in which erosion along the Gulf of Suez is initiated as rift flank uplift becomes sufficiently large ot expose the friable sandstones. Undercutting the escarpment and exhumation of basement has been propagating northward and westward for at least 20 m.y. The average rate of scarp retreat has been 6 km/m.y. and the along-strike propagation of the erosion has been 12 km/m.y. The diachronous erosion of the rift flanks at the Gulf of Suez highlights the importance of distinguishing between the timing of uplift and of erosion. Both thermochronometric and stratigraphic data primarily indicate the timing of erosion, which

  6. 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.

  7. Oligonucleotides containing an acridine group covalently bonded to the nucleotide flanking the 3'-3' phosphodiester junction for alternate strand triple helix formation.

    PubMed

    Catalanotti, Bruno; Fattorusso, Caterina; Mayol, Luciano; Oliviero, Giorgia; Piccialli, Gennaro; Varra, Michela

    2003-01-01

    Oligonucleotides with a 3'-3' inversion of polarity and containing an acridine group attached to nucleotide base flanking the 3'-3' phosphodiester bon have been synthesized, characterized and used as third strand in alternate triple helix formation. CD melting studies and molecular mechanics calculations have been carried out to investigate these triplex structures.

  8. 5'-flanking sequences of zebrafish fast myosin heavy chain genes regulate unique expression in the anterior, medial subsection and posterior tail somites of the skeletal muscle.

    PubMed

    Asaduzzaman, M; Shakur Ahammad, A K; Asakawa, S; Kinoshita, S; Watabe, S

    2016-01-01

    In zebrafish, fast muscle-specific myosin heavy chain genes have their unique expression patterns in a well-defined and restricted region of the skeletal muscle. However, the transcriptional regulatory mechanisms involved have remained unclear. Here, we examined the regulation of spatio-temporal expression patterns of myhz1 (myhz1.1, myhz1.2 and myhz1.3) and myhz2 during their development by using transient gene and stable transgenic techniques. Embryos microinjected with different length 5'-flanking sequences of myhz1 conjugated with the enhanced green fluorescent protein (EGFP) gene showed EGFP expression in the anterior and medial subsections of somites, but not in the tail somite region. In contrast, embryos microinjected with different length 5'-flanking sequences of myhz2 showed EGFP expression exclusively at the posterior tail somite domain. Promoter deletion analyses demonstrated that reduced EGFP fluorescence typically is correlated with smaller 5'-flanking sequences. The immunohistochemical observation revealed that zebrafish larvae provided with the transient gene and those from stable transgenic lines consistently expressed EGFP in the fast muscle fibers. r-VISTA plot identified one common conserved region of about 140°bp among myhz1.1, myhz1.2 and myhz1.3. Deletion of this conserved region from the 5'-flanking sequence of each myhz1 markedly reduced EGFP expression in its unique spatial somite region. Deletion mutation analysis demonstrated that myhz2 expression in the tail somite region might be mediated by Tbx (family of transcription factors having a common DNA-binding sequence known as T-box) binding elements. In summary, 5'-flanking sequences of myhz1 and myhz2 regulate their unique expression patterns in a well-defined and restricted somite region of the skeletal muscle in zebrafish.

  9. 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.

  10. High precision locations of microseismicity on south-eastern flank of Mt. Etna: reconstruction of fault planes geometry and related dynamic

    NASA Astrophysics Data System (ADS)

    Salvatore, A.; Savatore, G.; Vincenza, M.

    2006-12-01

    Since the beginning of 2001 Mt. Etna seismic activity revealed a change in the dynamic conditions acting on the volcano revealed by moderate-high levels of seismicity mainly restricted to the eastern flank of the edifice. The 2001-2006 period has been characterized by the 2001, 2002-2003 and 2004-2005 eruptive episodes and by a marked eastward displacement of the eastern flank. Hypocenters of eastern flank seismicity have been relocated applying two different techniques: the double- difference approach of Waldhauser and Ellsworth (2000) and a multiplets technique that use a cross-spectrum method based on that discussed by Fremont and Malone (1987). For the last technique we also investigated the presence of possible multiplet events measuring the waveform similarity with a cross-correlation function. The two approach give as very similar results furnishing high-precision locations of ca. 90 earthquakes distributed along some structure oriented ca. NE-SW and NW-SE; these alignments are in agreement with fault plane solutions (FPSs) calculated for all the events. This approach has allowed us to define: a) geometry of some depth structures of the eastern flank that have no surface evidences. b) the complex dynamic of these structure that may give new elements to the scientific debate about the causes of the large deformative effects measured on the eastern flank of the edifice. Frèmont, M.J., Malone, S.D., 1987. High precision relative locations of earthquake at Mount St. Helens, Washington. J. Geophy. Res., 92, 10223-10236. Waldhauser F. and W.L. Ellsworth, 2000 A double-difference earthquake location algorithm: Method and application to the northern Hayward fault, Bull. Seism. Soc. Am., 90, 1353-1368.

  11. 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.

  12. 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.

  13. Molecular Interaction between the Chaperone Hsc70 and the N-terminal Flank of Huntingtin Exon 1 Modulates Aggregation*

    PubMed Central

    Monsellier, Elodie; Redeker, Virginie; Ruiz-Arlandis, Gemma; Bousset, Luc; Melki, Ronald

    2015-01-01

    The aggregation of polyglutamine (polyQ)-containing proteins is at the origin of nine neurodegenerative diseases. Molecular chaperones prevent the aggregation of polyQ-containing proteins. The exact mechanism by which they interact with polyQ-containing, aggregation-prone proteins and interfere with their assembly is unknown. Here we dissect the mechanism of interaction between a huntingtin exon 1 fragment of increasing polyQ lengths (HttEx1Qn), the aggregation of which is tightly associated with Huntington's disease, and molecular chaperone Hsc70. We show that Hsc70, together with its Hsp40 co-chaperones, inhibits HttEx1Qn aggregation and modifies the structural, seeding, and infectious properties of the resulting fibrils in a polyQ-independent manner. We demonstrate that Hsc70 binds the 17-residue-long N-terminal flank of HttEx1Qn, and we map Hsc70-HttEx1Qn surface interfaces at the residue level. Finally, we show that this interaction competes with homotypic interactions between the N termini of different HttEx1Qn molecules that trigger the aggregation process. Our results lay the foundations of future therapeutic strategies targeting huntingtin aggregation in Huntington disease. PMID:25505179

  14. 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

  15. 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

  16. Shaking of pyroclastic cones and the formation of granular flows on their flanks: Results from laboratory experiments

    NASA Astrophysics Data System (ADS)

    Cagnoli, B.; Romano, G. P.; Ventura, G.

    2015-11-01

    We have carried out laboratory experiments to study the generation of granular flows on the slopes of pyroclastic cones that are experiencing volcanic tremor or tectonic earthquakes. These experiments are inspired by the occurrence of granular flows on the flanks of Mount Vesuvius during its 1944 eruption. Our laboratory model consists of sand cones built around a vibrating tube which represents a volcanic conduit with erupting magma inside. A video camera allows the study of the granular flow inception, movement and deposition. Although the collapse of the entire cone is obtained at a specific resonance frequency, single granular flows can be generated by all the vibration frequencies (1-16 Hz) and all the vibration amplitudes (0.5-1.5 mm) that our experimental apparatus has allowed us to adopt. We believe that this is due to the fact that the energy threshold to trigger the flows is small in value. Therefore, if this is true in nature as well, shaken pyroclastic cones are always potentially dangerous because they can easily generate flows that can strike the surrounding areas.

  17. Insight from Laboratory Experiments on the Generation of Granular Flows on the Flanks of Vibrated Pyroclastic Cones

    NASA Astrophysics Data System (ADS)

    Cagnoli, B.; Romano, G. P.; Ventura, G.

    2015-12-01

    We have carried out laboratory experiments to study the generation of granular flows on the slopes of pyroclastic cones that are experiencing volcanic tremor or tectonic earthquakes. These experiments are inspired by the occurrence of granular flows on the flanks of Mount Vesuvius during its 1944 eruption. Our laboratory model consists of sand cones built around a vibrating tube which represents a volcanic conduit with erupting magma inside. A video camera allows the study of the granular flow inception, movement and deposition. Although the collapse of the entire cone is obtained at a specific resonance frequency, individual granular flows can be generated by all the vibration frequencies and all the vibration amplitudes that our experimental apparatus has allowed us to adopt. We believe that this is due to the fact that the energy threshold to generate the flows is small in value. Therefore, if this is true in nature as well, shaken pyroclastic cones are always potentially dangerous because they can easily generate flows that can strike the surrounding areas.

  18. 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

  19. 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.

  20. 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

  1. 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.

  2. 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.

  3. Rift flank uplift and isostatic response to glacial erosion: Creation of a high-elevation continental margin.

    NASA Astrophysics Data System (ADS)

    McGregor, E. D.; Nielsen, S. B.; Stephenson, R. A.; Clausen, O. R.; Petersen, K. D.; Macdonald, D. I. M.

    2012-04-01

    Southern Baffin Island lies to the west of Davis Strait, which is part of a sedimentary basin system, linking Labrador Sea and Baffin Bay. It developed during Cretaceous and Palaeocene rifting that culminated in a brief period of sea-floor spreading in the late Palaeocene and Eocene. To date the cause of the high elevation southeastern margin of Baffin Island has not been a focus of much research, whereas the origin and age of elevated topography on its conjugate west Greenland margin is a matter of lively debate. For west Greenland it has been argued by some authors, from interpretations of on- and offshore data (fission track, seismic and well), that onshore topography was created by tectonically-driven uplift in the Neogene. However, we have previously demonstrated that offshore seismic and well data along the Greenland margin of Davis Strait are consistent with a model of rifting followed by thermal subsidence and fjord excavation by glaciers, where Neogene tectonic uplift is not required. For southeastern Baffin Island, we have analysed offshore seismic reflection profiles, exploration well and gravity data along the western margin of Davis Strait and conclude that rift flank uplift of older remnant topography and subsequent isostatic response to glacial erosion have produced the present-day high elevation onshore. This interpretation of the offshore evolution conforms with an onshore evolution for which elevated topography is related to erosion of pre-existing topography.

  4. Genetic flanking markers refine diagnostic criteria and provide insights into the genetics of Von Hippel Lindau disease

    SciTech Connect

    Seizinger, B.R.; Anderson, K.M.; Freiman, R.N.; Klauck, W.M.; Whaley, J.; Decker, H.J.H.; Martuza, R.L.; Gusella, J.F.; Haines, J.L. ); Smith, D.I. ); Filling-Katz, M.R. ); Neumann, J.; Scherer, G. ); Green, J.S. ); Choyke, P.L.; Gorin, M.B. ); Hsia, Y.E. ); Collins, D. ); Halperin, J. ); Lamiell, J.M. ); Oostra, B. ); Waziri, M.H. ); Drabkin, H.A. ); Aronin, N. (Univ. of Massachusetts, Worcester

    1991-04-01

    Von Hippel Lindau disease (VHL) is a hereditary syndrome, associated with tumors and cysts in multiple organ systems, whose expression and age of onset are highly variable. The availability of a genetic test for the early and reliable detecton of individuals carrying the defective gene sould be beneficial for VHL patients and their relatives, since many of the manifestations of VHL can be successfully treated if detected in their early stages, while the complicatons of undetected disease can be devastating. The authors have previoulsy shown that the VHL gene maps to chromosome 3p. To provide genetic markers for the development of a reliable diagnostic test, and to further narrow and eventually clone the VHL defect, they have generated DNA markers for chromosome 3p. With these markers, they have performed a multipoint genetic linkage analysis in 28 VHL pedigrees, comprising 470 individuals, 164 of whom were affected with VHL. Here they report the identification of tightly linked markers, including flanking markers that bracket the VHL gene to a small region on chromosome 3p25-p26.

  5. 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.

  6. 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

  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. 5' flanking sequence and genomic structure of Egr-1, a murine mitogen inducible zinc finger encoding gene.

    PubMed

    Tsai-Morris, C H; Cao, X M; Sukhatme, V P

    1988-09-26

    Egr-1 is a murine zinc finger encoding cDNA whose expression is modulated by a variety of ligand-receptor interactions and is often coregulated with c-fos (1). This study reports the isolation of a mouse Egr-1 genomic clone, its intron-exon structure, and 935 bp of 5' flanking sequence. The gene spans about 3.8 kb and consists of 2 exons and one 700 bp intron. S1 nuclease protection and primer extension analysis were used to define the transcription initiation site. "TATA" and "CCAAT" sequences were located at nucleotides -26 and -337 respectively. In addition, there exist five elements whose sequence is nearly identical to the inner core 10 nucleotide region (CCATATTAGG) of the c-fos serum response element, four Sp1 consensus sequences, two AP1 target sequence analogs, and two potential cAMP response elements. These results will ultimately lead to a detailed definition of the intracellular events regulating Egr-1 expression.

  9. A large duplication associated with dominant white color in pigs originated by homologous recombination between LINE elements flanking KIT.

    PubMed

    Giuffra, Elisabetta; Törnsten, Anna; Marklund, Stefan; Bongcam-Rudloff, Erik; Chardon, Patrick; Kijas, James M H; Anderson, Susan I; Archibald, Alan L; Andersson, Leif

    2002-10-01

    The Dominant White (I/KIT) locus is one of the major coat color loci in the pig. Previous studies showed that the Dominant White (I) and Patch (IP) alleles are both associated with a duplication including the entire KIT coding sequence. We have now constructed a BAC contig spanning the three closely linked tyrosine kinase receptor genes PDGFRA-KIT-KDR. The size of the duplication was estimated at about 450 kb and includes KIT, but not PDGFRA and KDR. Sequence analysis revealed that the duplication arose by unequal homologous recombination between two LINE elements flanking KIT. The same unique duplication breakpoint was identified in animals carrying the I and IP alleles across breeds, implying that Dominant White and Patch alleles are descendants of a single duplication event. An unexpected finding was that Piétrain pigs carry the KIT duplication, since this breed was previously assumed to be wild type at this locus. Comparative sequence analysis indicated that the distinct phenotypic effect of the duplication occurs because the duplicated copy lacks some regulatory elements located more than 150 kb upstream of KIT exon 1 and necessary for normal KIT expression.

  10. Heterogeneity, anisotropy, and compartmentalization of fluid, heat, and solute transport in the upper ocean crust on ridge flanks (Invited)

    NASA Astrophysics Data System (ADS)

    Fisher, A. T.; Becker, K.; Wheat, C. G.

    2010-12-01

    The volcanic oceanic crust is the largest aquifer on Earth, containing as much water as is stored worldwide in icecaps and glaciers. Much of this fluid is in motion, transporting heat and solutes across vast distances, transforming Earth's lithosphere, hydrosphere, and biosphere. Experiments completed as part of recent scientific ocean drilling expeditions are helping to quantify the nature of hydrogeologic processes within the upper oceanic crust on ridge flanks, resolving driving forces, and defining the extent and variability of fluid flow pathways. Although the upper oceanic crust is often idealized as having a simple geometry, its complex formation and evolution, through a variety of tectonic and geochemical processes, results in development of an intricate network of hydrogeologic channels and compartments. In some areas, drilling, sampling and measurements demonstrate that fluids travel tens of kilometers along continuous paths between hydrothermal recharge and discharge sites, but samples taken from adjacent locations indicate significant differences in fluid composition, suggesting the lack of a hydrologic connection. Long-term observatory data and samples, and fluids extracted from sediment cores collected from just above basement, also indicate preferred orientations in fluid, heat, and solute transport. Reconciling these disparate observations requires acknowledging the complexity of the ocean crustal hydrothermal reservoir. Controlled perturbation and long-term monitoring experiments help to test the extent of hydrologic connectivity at the spatial and temporal scales of global hydrologic processes.

  11. HNRNPA1 interacts with a 5′ flanking distal element of interleukin 6 and up-regulates its basal transcription

    PubMed Central

    Zheng, Dongling; Worthington, Jenny; Timms, John F.; Woo, Patricia

    2013-01-01

    Interleukin-6 (IL-6) is an important pro-inflammatory cytokine involved in many autoimmune and inflammatory diseases. We have shown previously that a region from −5307 to −5202 bp upstream of the IL-6 transcriptional start site is responsible for basal IL-6 gene expression and that there were DNA binding proteins involved from EMSA and transient expression experiments. Here we have combined surface plasmon resonance technology with mass spectrometry analysis and identified nuclear proteins bound to this region. HNRNPA1 and HNRNPA2B1 were found consistently. EMSA supershift and chromatin immunoprecipitation assays confirmed the involvement of HNRNPA1, but not HNRNPA2B1. Knocking down HNRNPA1 expression by siRNA resulted in reduced IL-6 transcriptional activity as assessed from transfection experiments using reporter constructs, mRNA and protein measurements. Overexpression of HNRNPA1 cDNA increased IL-6 mRNA expression. This regulation was dependent on the presence of the sequence from −5307 to −5202 bp of the IL-6 gene. Thus, HNRNPA1 is a novel transcriptional regulator of IL-6 expression, acting via the 5′ flanking sequence of the gene. PMID:23985572

  12. RAD-Seq derived markers flank the shell colour and banding loci of the Cepaea nemoralis supergene.

    PubMed

    Richards, Paul M; Liu, M Maureen; Lowe, Natalie; Davey, John W; Blaxter, Mark L; Davison, Angus

    2013-06-01

    Studies on the classic shell colour and banding polymorphism of the land snail Cepaea played a crucial role in establishing the importance of natural selection in maintaining morphological variation. Cepaea is also a pre-eminent model for ecological genetics because the outward colour and banding phenotype is entirely genetically determined, primarily by a 'supergene' of at least five loci. Unfortunately, progress in understanding the evolution and maintenance of the Cepaea polymorphism stalled, partly because of a lack of genetic markers. With a view to re-establish Cepaea as a prominent model of molecular ecology, we made six laboratory crosses of Cepaea nemoralis, five of which segregated for shell ground colour (C) and the presence or absence of bands (B). First, scoring of colour and banding in 323 individuals found no recombination between the C and B loci of the supergene. Second, using restriction site-associated DNA sequencing (RAD-Seq) of two parents and 22 offspring, we identified 44 anonymous markers putatively linked to the colour (C) and banding (B) loci. The genotype of eleven of the most promising RAD-Seq markers was independently validated in the same 22 offspring, then up to a further 146 offspring were genotyped. The closest RAD-Seq markers scored are within ~0.6 centimorgan (cM) of the C-B supergene linkage group, with the combined loci together forming a 35.8 cM linkage map of markers that flank both sides of the Cepaea C-B supergene.

  13. The human genes for hemophilia A and hemophilia B flank the X chromosome fragile site at Xq27.3.

    PubMed Central

    Purrello, M; Alhadeff, B; Esposito, D; Szabo, P; Rocchi, M; Truett, M; Masiarz, F; Siniscalco, M

    1985-01-01

    Two DNA recombinant clones, shown by separate studies to contain DNA sequences homologous to the genes coding for the human blood coagulation Factors VIII and IX, were hybridized in situ to metaphases or prometaphases derived from patients with the fragile-X syndrome and from a normal control. The results of these experiments indicate that (i) both genes are located in the subtelomeric region of the long arm of the human X chromosome flanking the fragile site at Xq27.3, (ii) the resolution of this localization is approximately 0.5% the length of the human haploid genome, i.e., 1.8 X 10(7) bp, (iii) the linear order of loci within the above region is Factor IX-fragile site-Factor VIII-Xqter. Both the localization and the linear order of these loci have been confirmed by Southern blotting studies using the same molecular probes and a panel of rodent-human somatic cell hybrids known to have retained different segments of the human X chromosome. The findings described herein and the knowledge that Factor IX deficiency recombines freely with at least two loci of the G6PD cluster support our hypothesis that the chromosomal region which includes the fragile-X site is normally a region of high meiotic recombination. Images Fig. 2. Fig. 3. PMID:3924593

  14. 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.

  15. Genetic diversity, paraphyly and incomplete lineage sorting of mtDNA, ITS2 and microsatellite flanking region in closely related Heliopora species (Octocorallia).

    PubMed

    Yasuda, Nina; Taquet, Coralie; Nagai, Satoshi; Fortes, Miguel; Fan, Tung-Yung; Harii, Saki; Yoshida, Terutoyo; Sito, Yuta; Nadaoka, Kazuo

    2015-12-01

    Examining genetic diversity and lineage sorting of different genes in closely related species provide useful information for phylogenetic analyses and ultimately for understanding the origins of biodiversity. In this study, we examined inter- and intraspecific genetic variation in internal transcribed spacer 2 (ITS2), partial mitochondrial gene (mtMutS), and nuclear microsatellite flanking region in two closely related octocoral species (Heliopora coerulea, HC-A and HC-B). These species were recently identified in a population genetic study using microsatellite markers. The two species have different reproductive timing, which ecologically promotes lineage sorting. In this study, we examined whether species boundaries could be detected by the commonly used nuclear ITS2 and mtMutS, as well as by possibly neutral microsatellite flanking sequences. Haplotype network analysis of microsatellite flanking region revealed that a possible ancestral haplotype was still shared between the two species, indicating on-going lineage sorting. Haplotype network analysis of ITS2 and microsatellite flanking region revealed shared haplotypes between the two lineages. The two species shared fewer ITS2 sequences than microsatellite flanking region sequences. The almost fixed point mutation at the tip of helix 3 of ITS2 was not associated with the secondary structure or compensatory base changes (CBCs). The phylogenetic tree of ITS2 showed paraphyly and that of the microsatellite flanking region indicated that lineage sorting for the two species may be incomplete. Much higher intra- and inter-individual variation of ITS2 was observed in HC-B than that in HC-A, highlighting the importance of examining ITS2 from multiple individuals to estimate genetic diversity. The mitochondrial mtMutS gene sequences from 39 individuals, including both species collected from Japan and Taiwan, showed no variation because of slow rates of mitochondrial nucleotide substitution. This study suggests caution

  16. 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

  17. Anatomy of a deep sub-surface ridge flank aquifer: The "Red Brick" Horizon in ODP Hole 1256D

    NASA Astrophysics Data System (ADS)

    Teagle, D. A.; Smith-Duque, C. E.; Harris, M.; Rutter, J.; Coggon, R. M.; Tominaga, M.; Alt, J.; Murphy, B.; Banerjee, N.

    2012-12-01

    Long-lived conductive heat flow deficits, near isothermal basement temperatures, and sedimentary pore water profiles from mid-ocean ridge flanks provide compelling arguments for the substantial lateral movement of seawater-derived fluids within the upper oceanic crust. However, there are few descriptions of zones within the oceanic basement for which there is strong evidence for sustained low temperature hydrothermal fluid flow and alteration. This paper describes a distinctive horizon of intense low temperature alteration encountered in ODP Hole 1256D. Hole 1256D, located on 15 million-year-old East Pacific Rise crust formed at a superfast spreading rate (>200 mm/yr) provides a reference section for fast spreading ocean crust and is the only well to sample a complete section of lavas, sheeted dikes, and into the upper most gabbros. The volcanic sequences at Hole 1256D are >800 m thick. The Red Brick horizon occurs at ~400 m sub-basement (msb) in massive and sheet flows that overly a ~30 m-thick zone of massive flows. These flows probably crystallized at the base of the ridge axial slope within a few 1000 meters of the ridge axis (Tominaga and Umino, 2010). The Red Brick horizon comprises a 50 cm-thick zone of massive, sparsely olivine-phyric microcrystalline basalt that is very strongly (80 to 90%) hydrothermally altered. Olivine, clinopyroxene, and plagioclase are replaced by beidellite, celadonite, K feldspar and iron oxyhydroxide, imparting blue-green and brick red colors to the rock. These secondary minerals plus quartz and carbonate also fill vugs and pore space. Compared to surrounding basalts that exhibit only background levels of low temperature alteration, the rocks of the Red Brick zone are strongly oxidized (Fe3+/FeTot >0.7), hydrated (>4 wt.%), and have highly elevated concentrations of alkali metals (K, Rb, Cs) and Mg. There are strong reductions in Si, Ca, Mn, Zn and Cu. Bulk rock oxygen isotope (δ18O ~8.5 to 9 per mil) indicate hydrothermal

  18. Neocentromeres in 15q24-26 Map to Duplicons Which Flanked an Ancestral Centromere in 15q25

    PubMed Central

    Ventura, Mario; Mudge, Jonathan M.; Palumbo, Valeria; Burn, Sally; Blennow, Elisabeth; Pierluigi, Mauro; Giorda, Roberto; Zuffardi, Orsetta; Archidiacono, Nicoletta; Jackson, Michael S.; Rocchi, Mariano

    2003-01-01

    The existence of latent centromeres has been proposed as a possible explanation for the ectopic emergence of neocentromeres in humans. This hypothesis predicts an association between the position of neocentromeres and the position of ancient centromeres inactivated during karyotypic evolution. Human chromosomal region 15q24-26 is one of several hotspots where multiple cases of neocentromere emergence have been reported, and it harbors a high density of chromosome-specific duplicons, rearrangements of which have been implicated as a susceptibility factor for panic and phobic disorders with joint laxity. We investigated the evolutionary history of this region in primates and found that it contains the site of an ancestral centromere which became inactivated about 25 million years ago, after great apes/Old World monkeys diverged. This inactivation has followed a noncentromeric chromosomal fission of an ancestral chromosome which gave rise to phylogenetic chromosomes XIV and XV in human and great apes. Detailed mapping of the ancient centromere and two neocentromeres in 15q24-26 has established that the neocentromere domains map approximately 8 Mb proximal and 1.5 Mb distal of the ancestral centromeric region, but that all three map within 500 kb of duplicons, copies of which flank the centromere in Old World Monkey species. This suggests that the association between neocentromere and ancestral centromere position on this chromosome may be due to the persistence of recombinogenic duplications accrued within the ancient pericentromere, rather than the retention of “centromere-competent” sequences per se. The high frequency of neocentromere emergence in the 15q24-26 region and the high density of clinically important duplicons are, therefore, understandable in the light of the evolutionary history of this region. PMID:12915487

  19. Intrinsically bent DNA flanks both sides of an RNA polymerase I transcription start site. Both regions display novel electrophoretic mobility.

    PubMed

    Schroth, G P; Siino, J S; Cooney, C A; Th'ng, J P; Ho, P S; Bradbury, E M

    1992-05-15

    We have identified two intrinsically bent regions of DNA which flank the transcription start site of the rRNA gene from Physarum polycephalum. DNA fragments from both regions were analyzed by circular permutation polyacrylamide gel electrophoresis assay and computer modeling. Both types of analysis indicate that one fragment contains a relatively simple bend centered about 160 base pairs (bp) upstream of the transcription start site while the other fragment contains multiple bends, the most prominent of which is centered about 150 bp downstream of the start site. According to both gel mobilities and computer modeling we estimate that the net bending in each is about 45 degrees. These fragments were studied in detail by varying parameters of electrophoresis that are known to affect bending. Previous work indicates that anomalous mobility should decrease when temperature or ethidium bromide concentration is increased, whereas anomalous mobility should increase when polyacrylamide gel percentage is increased. The anomalous mobility of both fragments decreases as temperature is raised from 4 to 65 degrees C, although the bent structure centered at -160 bp is more temperature labile than the bend at +150 bp. Strikingly different behavior was observed for the two fragments as the polyacrylamide concentrations was varied. As polyacrylamide concentrations are increased from 6 to 10%, the anomalous mobility of the bend centered at -160 bp increases while that of the bend centered at +150 bp decreases. The bend centered at +150 bp is "straightened" at all ethidium concentrations tested. In sharp contrast and unexpectedly, the anomalous migration of the bend centered at -160 bp increases dramatically in 0.1 micrograms/ml ethidium bromide. Many of the mobility differences we observe suggest that the two regions studied represent structurally distinct forms of bent DNA. The location of these strongly bent regions on either side of a RNA polymerase I transcription start site

  20. 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.

  1. Polymorphisms in the 5'-flanking regions of the GH, PRL, and Pit-1 genes with Muscovy duck egg production.

    PubMed

    Xu, Z Q; He, J; Ji, C L; Zhang, Y; Nie, Q H; Zhang, D X; Zhang, X Q

    2015-01-01

    Somatotropic axis-related genes contribute to reproduction of ducks. Five SNP in the 5'-flanking regions of the growth hormone (GH), prolactin (PRL), and pituitary-specific transcription factor (Pit-1) genes were identified and genotyped in a female population of Muscovy ducks. Association analysis of these SNP with Muscovy duck egg production traits was performed. Results showed that SNP C-515G of GH was significantly associated with egg number in ducks at age 59 wk (E59W; P = 0.0009) and egg number in ducks at age 300 d (E300D; P = 0.0022). Single nucleotide polymorphism C-441T of GH was significantly associated with E59W (P = 0.0014). Significant associations of SNP T-884C and T-335C of PRL with the age at first egg (A1D), E59W, and E300D were detected in this population (P < 0.0001). It was concluded that these 4 SNP might be useful markers to use with the aim of increasing Muscovy duck E59W. On the basis of genetic parameter estimation, the heritability of A1D, E300D, E59W, and molting time were 0.43 ± 0.04, 0.45 ± 0.04, 0.36 ± 0.04, and 0.04 ± 0.03, respectively. Strong positive genetic correlation was noted between E59W and E300D (correlation coefficient = 0.80), whereas a negative association was noted between E59W and A1D (correlation coefficient = -0.80). Therefore, the selection for improved A1D should also increase E59W.

  2. 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

  3. 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.

  4. Stratigraphy of Blair formation, an Upper Cretaceous slope and basin deposit, eastern flank of the Rock Springs Uplift, Wyoming

    SciTech Connect

    Shannon, L.T.

    1985-05-01

    The Blair Formation (Upper Cretaceous) is the lowermost unit of the Mesaverde Group in southwestern Wyoming. Outcrop study of the Blair exposures on the east flank of the Rock Springs uplift reveals 1,100 ft (330 m) of sandstone, siltstone, and shale. The formation has a sharp conformable to locally erosional basal contact and contains intraformational channeling, syndepositional slumping, and high-energy sedimentary structures. Facies relationships indicate the Blair represents a slope and basinal deposit laterally equivalent to the shelf and delta complex of the lower Rock Springs Formation to the north. Overall stratification types, textures, and southeast paleotransport directions recorded within the Blair, which are normal to the southwest-trending Rock Springs shoreline, support this interpretation. High sedimentation rates in excess of subsidence rates during the early Campanian, possibly related to early movement on the Absaroka thrust and a eustatic lowering of sea level approximately 81 Ma, caused rapid shoreline progradation and favored the development of a narrow shelf. These conditions enabled sand-sized material to bypass the shelf and be deposited in slope and basin environments. A present-day example of these relationships is the modern Mississippi delta located near the shelfslope break of the Gulf of Mexico. Recognition of a narrow shelf in southwestern Wyoming during the early Campanian requires a modification of Late Cretaceous paleogeography to incorporate the concept of depositional topography. The occurrence of slope and basin sandstones in the Blair suggests that new interpretations may be needed to explain sandstone distribution for other stratigraphic intervals within the Cretaceous of the Western Interior.

  5. 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

  6. 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

  7. 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

  8. 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.

  9. 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

  10. 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.

  11. 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

  12. Elevation of transgene expression level by flanking matrix attachment regions (MAR) is promoter dependent: a study of the interactions of six promoters with the RB7 3' MAR.

    PubMed

    Mankin, S Luke; Allen, George C; Phelan, Thomas; Spiker, Steven; Thompson, William F

    2003-02-01

    We have analyzed effects of a matrix attachment region (MAR) from the tobacco RB7 gene on transgene expression from six different promoters in stably transformed tobacco cell cultures. The presence of MARs flanking the transgene increased expression of constructs based on the constitutive CaMV 35S, NOS, and OCS promoters. Expression from an induced heat shock promoter was also increased and MARs did not cause expression in the absence of heat shock. There was also no effect of MARs on the pea ferredoxin promoter, which is not normally expressed in this cell line. Importantly, most transgenes flanked by RB7 MAR elements showed a large reduction in the number of low expressing GUS transformants relative to control constructs without MARs. PMID:12650520

  13. Fusion primer and nested integrated PCR (FPNI-PCR): a new high-efficiency strategy for rapid chromosome walking or flanking sequence cloning

    PubMed Central

    2011-01-01

    Background The advent of genomics-based technologies has revolutionized many fields of biological enquiry. However, chromosome walking or flanking sequence cloning is still a necessary and important procedure to determining gene structure. Such methods are used to identify T-DNA insertion sites and so are especially relevant for organisms where large T-DNA insertion libraries have been created, such as rice and Arabidopsis. The currently available methods for flanking sequence cloning, including the popular TAIL-PCR technique, are relatively laborious and slow. Results Here, we report a simple and effective fusion primer and nested integrated PCR method (FPNI-PCR) for the identification and cloning of unknown genomic regions flanked known sequences. In brief, a set of universal primers was designed that consisted of various 15-16 base arbitrary degenerate oligonucleotides. These arbitrary degenerate primers were fused to the 3' end of an adaptor oligonucleotide which provided a known sequence without degenerate nucleotides, thereby forming the fusion primers (FPs). These fusion primers are employed in the first step of an integrated nested PCR strategy which defines the overall FPNI-PCR protocol. In order to demonstrate the efficacy of this novel strategy, we have successfully used it to isolate multiple genomic sequences namely, 21 orthologs of genes in various species of Rosaceace, 4 MYB genes of Rosa rugosa, 3 promoters of transcription factors of Petunia hybrida, and 4 flanking sequences of T-DNA insertion sites in transgenic tobacco lines and 6 specific genes from sequenced genome of rice and Arabidopsis. Conclusions The successful amplification of target products through FPNI-PCR verified that this novel strategy is an effective, low cost and simple procedure. Furthermore, FPNI-PCR represents a more sensitive, rapid and accurate technique than the established TAIL-PCR and hiTAIL-PCR procedures. PMID:22093809

  14. Implementing reverse genetics in Rosaceae: analysis of T-DNA flanking sequences of insertional mutant lines in the diploid strawberry, Fragaria vesca.

    PubMed

    Oosumi, Teruko; Ruiz-Rojas, Juan Jairo; Veilleux, Richard E; Dickerman, Allan; Shulaev, Vladimir

    2010-09-01

    Reverse genetics is used for functional genomics research in model plants. To establish a model system for the systematic reverse genetics research in the Rosaceae family, we analyzed genomic DNA flanking the T-DNA insertions in 191 transgenic plants of the diploid strawberry, Fragaria vesca. One hundred and seventy-six T-DNA flanking sequences were amplified from the right border (RB) and 37 from the left border (LB) by thermal asymmetric interlaced PCR. Analysis of the T-DNA nick positions revealed that T-DNA was most frequently nicked at the cleavage sites. Analysis of 11 T-DNA integration sites indicated that T-DNA was integrated into the F. vesca genome by illegitimate recombination, as reported in other model plants: Arabidopsis, rice and tobacco. First, deletion of DNA was found at T-DNA integration target sites in all transgenic plants tested. Second, microsimilarities of a few base pairs between the left and/or right ends of the T-DNA and genomic sites were found in all transgenic plants tested. Finally, filler DNA was identified in four break-points. Out of 191 transgenic plants, T-DNA flanking sequences of 79 plants (41%) showed significant similarity to genes, elements or proteins of other plant species and 67 (35%) of the sequences are still unknown strawberry gene fragments. T-DNA flanking sequences of 126 plants (66%) showed homology to plant ESTs. This is the first report of T-DNA integration in a sizeable population of a rosaceous species. We have shown in this paper that T-DNA integration in strawberry is not random but directed by sequence microsimilarities in the host genome.

  15. 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.

  16. Structural analysis of phage-borne stx genes and their flanking sequences in shiga toxin-producing Escherichia coli and Shigella dysenteriae type 1 strains.

    PubMed

    Unkmeir, A; Schmidt, H

    2000-09-01

    The stx-flanking regions of 49 Shiga toxin-producing Escherichia coli strains and nine Shigella dysenteriae serotype 1 strains containing either stx, stx(1), stx(2), or stx(2) variant genes, were examined. We analyzed these regions by PCR using a set of primers with one primer specific for the respective stx gene and a second primer complementary to sequences of Stx phages H-19B and 933W. We further characterized the amplification products by restriction endonuclease digestion and nucleotide sequencing. PCR products of stx(1)-containing E. coli strains of serogroups O157, O26, and 0103 showed the same lengths and similar restriction patterns. However, we failed to amplify the 3' stx-flanking region in stx(1)-harboring E. coli O111:H(-) strains. Stx2-producing E. coli strains revealed amplification products of different lengths and restriction patterns, suggesting greater heterogeneity than in stx(1)-positive strains. We also obtained specific PCR products for two Stx2c-producing and seven Stx2f-producing E. coli strains when they were subjected to PCR analysis. In nine S. dysenteriae type 1 strains, H-19B- and 933W-specific primers amplified only the 3' stx-flanking region. The results of our study demonstrate that the stx genes of all strains investigated are continuous with phage sequences. Whereas almost all strains except E. coli O111:H(-) strains were associated with a S-like gene, association with Q could not be demonstrated in nine S. dysenteriae type 1 strains and three E. coli strains. Furthermore, we showed that the organization of the stx-flanking regions is similar in all strains investigated, whereas fine-structure analysis showed subtle differences among the sequences examined. Our results support the hypothesis that stx genes in E. coli and S. dysenteriae are generally phage-borne.

  17. Combined GPS, EDM and triangulation surveys of the rapid down-slope motion of the western flank of Arenal Volcano, Costa Rica

    NASA Astrophysics Data System (ADS)

    Muller, C.; del Potro, R.; Gottsmann, J.; Biggs, J.; Van der Laat, R.

    2011-12-01

    Here we present initial conclusion of a one year-long combined geodesy campaign on Arenal Volcano, in Costa Rica (2008-2009). Our data shows evidence for an active local tectonic surrounding and a 7cm/yr displacement field on the western flank of the volcano edifice that is in general agreement with recent INSAR studies. Moreover, the rigorous combination of simultaneous GPS, EDM and triangulation measurements provide a time-cost effective approach to volcanic monitoring. Arenal volcano, in Costa Rica, is an active basaltic andesite stratovolcano located at the southern end of the Guanacaste volcanic range. Arenal's current long-lived magmatic activity may be coming to an end but downslope motion of the western flank suggests a risk of sector collapse. In order to study this, during 2008 and 2009 we deployed a joint geodetic network, comprising GPS, EDM (Electronic Distance Measurements) and triangulation measurements on a total of 12 benchmarks. Nine benchmarks monitor movements of the western flank of Arenal while three external benchmarks, located away from the volcanic system, monitor local tectonic movements. A joint adjustment of the combined network using the software suite GAMIT, FONDA and GLOBK allowed us to maintain a high repeatability along the time despite short field campaigns. In agreement with a quantitative comparison with existing INSAR, our results show a downward displacement on the western flank. However, in our full 3D survey, we observe that these displacements shift to a northern and even northeastern direction at the foot of the volcano. This suggests that if a sector collapse is underway it must have a northwestern direction. Our favoured preliminary explanation is, in agreement with local workers, that the deformation is caused by the weight of the recent lava field. The differential displacements between the three external points agree with neotectonic studies of the presence of active faults in the north of the Arenal graben.

  18. Elemental abundance analyses with Coudé Echelle spectrograms from the TÜBİTAK National Observatory of Turkey: I. The HgMn stars 11 Per, HR 2801, and ν Cnc

    NASA Astrophysics Data System (ADS)

    Adelman, S. J.; Yüce, K.

    2010-08-01

    Using coadded spectrograms taken with the Coudé Echelle Spectrograph (CES) of the 1.50-m Russian-Turkish Telescope of the TÜBİTAK National Observatory (TUG) near Antalya in Turkey, elemental abundance analyses of three HgMn stars 11 Per, HR 2801, and ν Cnc were performed. Comparisons are made with spectra obtained with the long camera of the Dominion Astrophysical Observatory (DAO) coudé spectrograph and its SITe4 CCD. The CES equivalent widths are about 12% larger than that for the DAO long camera. Our first results from TUG data/spectra show that all three stars exhibit the Hg II λ3984 line and somewhat diverse abundance patterns. 11 Per tends to have underabundant light elements with underabundant and overabundant Fe-peak elements. HR 2801 has mostly underabundant elements, with a few elements having solar abundances while N and Mn are overabundant. The coolest star ν Cnc has light elements having mostly solar abundances, overabundant iron group abundances, and very overabundant SrYZr and Ba. Comparisons with the abundance patterns of other HgMn stars show that they have a wide diversity of abundance patterns. Tables 2 and 6 are available at the CDS via http://cdsarc.u-strasbg.fr/cgi-bin/qcat?J/AN/331/785.

  19. 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.

  20. 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.

  1. Flanking regulatory sequences of the locus encoding the murine GDNF receptor, c-ret, directs lac Z (beta-galactosidase) expression in developing somatosensory system.

    PubMed

    Sukumaran, M; Waxman, S G; Wood, J N; Pachnis, V

    2001-11-01

    RET forms the catalytic component within the receptor complex that transmits signals from the GDNF family of neurotrophic factors. To study the mechanisms regulating the cell-type specific expression of this gene, we have cloned and characterised the murine c-ret locus. A cosmid contig comprising approximately 60 kb of the mouse genome encompassing the entire structural gene and flanking sequences have been isolated and the transcription initiation site identified and promoter characterised. The murine c-ret promoter lacks a TATA initiation motif and has GC enriched DNA sequences reminiscent of CpG islands. Analysis of transgenic mice lines bearing the Lac Z (beta-galactosidase) reporter gene under the control of 5' flanking sequences show modularity in the organisation of cis-regulatory domains within the locus. Cloned 5' flanking sequences comprise a distal regulatory domain directing Lac Z expression at the primitive streak, lateral mesoderm and facial ganglia and a proximal sensory neurones specific regulatory domain inducing Lac Z expression primarily within the developing somatosensory system. The spatial and temporal progression of transgene expression precisely recapitulates endogenous gene expression in developing sensory ganglia including its induction in postnatal Isolectin B4 binding nociceptive neurones. PMID:11747074

  2. Strong Quantum Coupling Between O-H+-O Stretch and Flanking Group Motions in (CH_3OH)_2H^+ Part i: Unmasking the 800-1200 wn Peaks

    NASA Astrophysics Data System (ADS)

    Tan, Jake Acedera; Kuo, Jer-Lai

    2016-06-01

    Assigning the vibrational signatures between 800-1200 wn is not a trivial task for (CH_3OH)_2H^+. Such complication in the assignment arises due to the intermode coupling between O-H+-O stretch and flanking group motions. In this talk, we will examine the interactions between O-H+-O stretch and four flanking group motions: 1) out-of-phase C-O stretch, 2) in-plane CH_3 rock, 3) out-of-plane CH_3, and 4) O-O stretch. Vibrational interactions were investigated by solving a reduced-dimensional Schrödinger equation by means of Discrete Variable Representation (DVR) with harmonic oscillators as basis. Potential and dipole moment surfaces were constructed by scanning along normal mode coordinates using MP2 and CCSD(T) level. It was found out that the O-H+-O stretch strongly couples with the four above mentioned flanking motions, leading to intensity redistribution on peaks between 800-1200 wn. J.R. Roscioli, L.R. McCunn and M.A. Johnson. Science 2007, 316, 249 T.D. Fridgen, L. Macaleese, T.B McMahon, J. Lemaire and P. Maitre. Phys. Chem. Chem. Phys. 2006, 8, 955-966 J.A. Tan and J.-L. Kuo. J. Phys. Chem. A. 2015, 119, 11320-11328

  3. 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

  4. 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

  5. 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

  6. 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

  7. Chlorine stable isotopic composition of basement fluids of the eastern flank of the Juan de Fuca Ridge (ODP Leg 168)

    NASA Astrophysics Data System (ADS)

    Bonifacie, Magali; Monnin, Christophe; Jendrzejewski, Nathalie; Agrinier, Pierre; Javoy, Marc

    2007-08-01

    This paper presents chlorine stable isotope compositions (δ 37Cl) of sediment pore waters collected by squeezing sediment cores from the sediment-basement interface along an East-West transect through the eastern flank of the Juan de Fuca Ridge (ODP Leg 168). These "near basement fluids" (NBF) are generally thought to be representative of low-temperature fluids circulating in the off-axis basaltic crust. The δ 37Cl value of the fluid directly sampled from a flow at the base of Site 1026 (WSTP1026) is also reported. NBF display δ 37Cl values between - 2.09‰ and - 0.12‰ relative to the Standard Mean Ocean Chloride (SMOC defined as 0‰) and small variations in chlorinity (˜ 4%). These data contrast with the homogeneity of δ 37Cl values associated with highly variable chlorinities observed in high-temperature on-axis fluids [M. Bonifacie, J.L. Charlou, N. Jendrzejewski, P. Agrinier, J.P. Donval, Chlorine isotopic compositions of ridge axis high temperature hydrothermal vent fluids, Chem. Geol. 221(2005) 279-288.]. The NBF δ 37Cl values show a general decreasing trend with distance from the ridge-axis except for two fluids. When plotted against δ 18O values, the δ 37Cl of the NBF show two different trends. This paper discusses the possible contributions on NBF δ 37Cl values of fluid-mixing, water-rock interactions and transport processes (diffusion, ion membrane filtration) that can occur in the igneous basement. However, as none of these processes can fully explain the observed δ 37Cl variations, the potential effect of the sediment cover is also investigated. At site 1026, the interstitial pore fluid displays a δ 37Cl signature significantly lower than that of the fluid discharge sample (- 1.90‰ and - 0.28‰, respectively). This difference, demonstrated here cannot be an artifact of the sampling method, rather indicates the influence of the sediment cover on NBF δ 37Cl values. The potential contributions of physical processes associated with

  8. Anomalously high b-values in the South Flank of Kilauea volcano, Hawaii: Evidence for the distribution of magma below Kilauea's East rift zone

    USGS Publications Warehouse

    Wyss, M.; Klein, F.; Nagamine, K.; Wiemer, S.

    2001-01-01

    The pattern of b-value of the frequency-magnitude relation, or mean magnitude, varies little in the Kaoiki-Hilea area of Hawaii, and the b-values are normal, with b = 0.8 in the top 10 km and somewhat lower values below that depth. We interpret the Kaoiki-Hilea area as relatively stable, normal Hawaiian crust. In contrast, the b-values beneath Kilauea's South Flank are anomalously high (b = 1.3-1.7) at depths between 4 and 8 km, with the highest values near the East Rift zone, but extending 5-8 km away from the rift. Also, the anomalously high b-values vary along strike, parallel to the rift zone. The highest b-values are observed near Hiiaka and Pauahi craters at the bend in the rift, the next highest are near Makaopuhi and also near Puu Kaliu. The mildest anomalies occur adjacent to the central section of the rift. The locations of the three major and two minor b-value anomalies correspond to places where shallow magma reservoirs have been proposed based on analyses of seismicity, geodetic data and differentiated lava chemistry. The existence of the magma reservoirs is also supported by magnetic anomalies, which may be areas of dike concentration, and self-potential anomalies, which are areas of thermal upwelling above a hot source. The simplest explanation of these anomalously high b-values is that they are due to the presence of active magma bodies beneath the East Rift zone at depths down to 8 km. In other volcanoes, anomalously high b-values correlate with volumes adjacent to active magma chambers. This supports a model of a magma body beneath the East Rift zone, which may widen and thin along strike, and which may reach 8 km depth and extend from Kilauea's summit to a distance of at least 40 km down rift. The anomalously high b-values at the center of the South Flank, several kilometers away from the rift, may be explained by unusually high pore pressure throughout the South Flank, or by anomalously strong heterogeneity due to extensive cracking, or by both

  9. Selective induction of apoptosis in the hamster flank sebaceous gland organ by a topical liposome 5-alpha-reductase inhibitor: a treatment strategy for acne.

    PubMed

    Li, Lingna; Tang, Li; Baranov, Eugene; Yang, Meng; Amoh, Yasuyuki; Katsuoka, Kensei; Hoffman, Robert M

    2010-02-01

    Acne is a very widespread cosmesis problem. Isotretinoin, a synthetic oral retinoid is used to treat acne, which is androgen dependent. Numerous side-effects occur from this treatment. 5-alpha-Reductase plays a critical role in normal and pathological androgen-dependent processes. We have taken the approach to develop a selective, effective, topically-applied 5-alpha-reductase inhibitor to modify unwanted or pathological processes in the pilosebaceous unit such as acne. Toward this goal, we have previously developed a selective liposome hair follicle targeting system. We demonstrate in this report that the 5-alpha-reductase inhibitor N,N-diethyl-4-methyl-3-oxo-4-aza-5alpha-androstane-17beta-carboxamide (4-MA) incorporated into liposomes induces apoptosis and inhibits growth of the dihydrotestosterone (DHT)-dependent hamster flank organ sebaceous gland. We have compared topical application of liposome 4-MA and solvent-formulated 4-MA and observed selective efficacy of topical application of liposome 4-MA by the reduction of size and induction of apoptosis only in the treated hamster flank organ. Apoptosis induced by liposome 4-MA in the treated flank organ sebaceous gland cells was observed both by assays for DNA fragments (transferase deoxytidyl uridine end labeling) and by observation of condensed and fragmented nuclei. When 4-MA was topically applied formulated in ethanol and glycerol without liposomes, the selective efficacy was lost. Liposome 4-MA did not significantly affect prostate weight, testosterone/DHT ratios or bodyweight gain compared to controls indicating safety as well as efficacy of topical application of liposome 4-MA for pathological processes such as acne. PMID:20175850

  10. Contrasting two-dimensional and three-dimensional models of outcrop-to-outcrop hydrothermal circulation on the eastern flank of the Juan de Fuca Ridge

    NASA Astrophysics Data System (ADS)

    Fisher, A. T.; Winslow, D. M.; Stauffer, P. H.; Gable, C. W.; Zyvoloski, G.

    2015-12-01

    We present results from two-dimensional and three-dimensional coupled (fluid and heat flow) simulations of ridge-flank hydrothermal circulation on the eastern flank of the Juan de Fuca Ridge. Field studies in this region demonstrate the existence of an active hydrothermal siphon operating between two seamounts separated by ~50 km, and provide quantitative constraints that help to determine which simulations are successful in replicating known properties and processes. Constraints from field observations include (a) the flow rate between the outcrops, (b) the presence of secondary convection within the basement aquifer, leading to simultaneous recharge and discharge through a single outcrop (in additional to siphon flow between outcrops), (c) direct measurements of crustal permeability in basement boreholes, and (d) the lack of a regional seafloor heat flux anomaly as a consequence of outcrop-to-outcrop circulation. New simulations include an assessment of crustal permeability and thickness, outcrop permeability, and a comparison of simulation results using different geometries. Three-dimensional simulations are more consistent with field observations than their two-dimensional counterparts and indicate a crustal aquifer of ≤300 m thick having a bulk permeability between 3×10-13 and 2×10-12 m2, values consistent with borehole measurements. In addition, we find fluid flow rates and crustal cooling efficiencies that are an order of magnitude greater in three-dimensional simulations than inferred from two-dimensional simulations using equivalent properties. These results show that three-dimensional simulations of outcrop-to-outcrop hydrothermal circulation on a ridge flank improves the geological and geometric accuracy of results, in comparison to models run in two dimensions.

  11. Geological and InSAR surveys highlight tectonic hazard in densely inhabited areas on the lower southeastern flank of Mount Etna volcano, Italy

    NASA Astrophysics Data System (ADS)

    Neri, Marco; Sansosti, Eugenio; Casu, Francesco; Leonardi, Anna; Pepe, Antonio; Pepe, Susi; Solaro, Giuseppe

    2015-04-01

    A constant seaward sliding mechanism is affecting the eastern to southern flanks of Mt. Etna volcano, involving an overall on-shore area of >700 km2.The margins of this unstable area are marked by the Pernicana Fault System to the north and the Ragalna Fault System to the south-west. The unstable area is divided into several blocks characterized by different kinematics and delimited by active faults crossing, in several cases, urban areas, towns and villages. One of these structural discontinuities is the Trecastagni-S.G.La Punta-Aci Trezza fault system, a tectonic structure extending from the volcano summit (where it trends NNW-SSE), to the lower southeastern flank (trending NW-SE) and reaching the coast at the Aci Trezza village (WNW-ESE and E-W). The last segment of this tectonic system crosses several important roads and man-made structures within Aci Trezza, and continues for a few kilometers off-shore crossing the Faraglioni stacks-Lachea island. Recently, analysis of long-period InSAR data has added some details to the sliding motion on the lower south-eastern flank of the volcano, particularly on the S.G.La Punta-Aci Trezza fault segments. Field geological and instrumental data confirmed the slip activity and the extension of the tectonically disturbed areas, highlighting a transition zone between the two main fault segments. On the other hand, some of the features detected by InSAR are not clearly visible in the field and were never detected before by classical geological surveys. These results are of crucial importance in terms of hazard related to tectonic movements, especially in densely inhabited zones such as the south-eastern flank of Etna, where more than half a million people live. The structural details obtained through these kinds of studies may guide future land use planning appropriately also within towns and villages, where aseismic and seismogenic very active faults are evident at the surfaces.

  12. Mt. Etna 2001 eruption: New insights into the magmatic feeding system and the mechanical response of the western flank from a detailed geodetic dataset

    NASA Astrophysics Data System (ADS)

    González, Pablo J.; Palano, Mimmo

    2014-03-01

    In the last decades, the increasing availability of comprehensive geodetic datasets has allowed for more detailed constraints on subsurface magma storage and conduits at several active volcanoes worldwide. Here, by using a large dataset of geodetic measurements collected between early January 2001 and August 2001, we identified at least six different deformation stages that allow us to quantify the surface deformation patterns before, during and after the 2001 Mt. Etna volcanic eruption. Our results are largely in agreement with previous works (e.g. the presence of a deep inflating source and a shallow dike located beneath the north-western and upper southern flanks of the volcano, respectively). However, we provide (1) finer resolution of the temporal activity of these magmatic sources, leading to (2) new evidence related to the evolution of the magmatic system and the mechanical response of the western flank, in particular during the pre-eruptive phase. Results and analysis show a clear change in the ground deformation pattern of the volcano in response to the 20-24 April 2001 seismic swarm that occurred beneath the western flank, evolving from a volcano-wide inflation to a slight deflation of the summit area. We suggest that the source responsible for the volcano-wide inflation, beginning in the fall of 2000, experienced a drastic reduction in the inflation rate in response to this seismic swarm. Moreover, we provide evidence for the presence of a new inflating source located beneath the upper southern flank at a depth of ~ 7.0 km bsl that triggered both the occurrence of the 20-24 April 2001 seismic swarm and led to the rapid ascent of magma upward to the surface after 12 July (the Lower Vents system was fed by fresh magma rising from this source). The presence of this inflating source is inferred by (1) seismological and volcanological observations coming from the 2001 eruption and (2) seismological constraints coming from a previous similar episode that

  13. Gravity and seismic study of crustal structure along the Juan de Fuca Ridge axis and across pseudofaults on the ridge flanks

    NASA Astrophysics Data System (ADS)

    Marjanović, Milena; Carbotte, Suzanne M.; Nedimović, Mladen R.; Canales, Juan Pablo

    2011-05-01

    Variations in topography and seismic structure are observed along the Juan de Fuca (JdF) Ridge axis and in the vicinity of pseudofaults on the ridge flanks left by former episodes of ridge propagation. Here we analyze gravity data coregistered with multichannel seismic data from the JdF Ridge and flanks in order to better understand the origin of crustal structure variations in this area. The data were collected along the ridge axis and along three ridge-perpendicular transects at the Endeavor, Northern Symmetric, and Cleft segments. Negative Mantle Bouguer anomalies of -21 to -28 mGal are observed at the axis of the three segments. Thicker crust at the Endeavor and Cleft segments is inferred from seismic data and can account for the small differences in axial gravity anomalies (3-7 mGal). Additional low densities/elevated temperatures within and/or below the axial crust are required to explain the remaining axial MBA low at all segments. Gravity models indicate that the region of low densities is wider beneath the Cleft segment. Gravity models for pseudofaults crossed along the three transects support the presence of thinner and denser crust within the pseudofault zones that we attribute to iron-enriched crust. On the young crust side of the pseudofaults, a 10-20 km wide zone of thicker crust is found. Reflection events interpreted as subcrustal sills underlie the zones of thicker crust and are the presumed source for the iron enrichment.

  14. The zinc finger domain of Tzfp binds to the tbs motif located at the upstream flanking region of the Aie1 (aurora-C) kinase gene.

    PubMed

    Tang, C J; Chuang, C K; Hu, H M; Tang, T K

    2001-06-01

    Our previous studies showed that Aie1 (aurora-C), is a novel testis kinase belonging to the aurora kinase family (). In this report, we describe a testis zinc finger protein (Tzfp) that binds to the upstream flanking sequence of the Aie1 gene. The mouse Tzfp gene, mapped to chromosome 7 B2-B3, encodes a 465-amino acid transcription factor containing a conserved N-terminal BTB/POZ domain and three C-terminal PLZF-like C(2)H(2) zinc fingers. The zinc finger domain of Tzfp binds to the TGTACAGTGT motif (Tzfp binding site, termed tbs) located at the upstream flanking sequence of the Aie1 gene by gel mobility shift, DNase I footprinting, and competition analyses. When the C-terminal zinc fingers of Tzfp were fused to the transactivation domain of VP16, the chimera activated transcription of a reporter construct containing multiple copies of the tbs. In contrast, the same chimera did not activate the reporter gene when an essential nucleotide fifth C was mutated to A at the tbs. Furthermore, we showed that the N-terminal BTB/POZ domain of TZFP has a repressor activity. Taken together, our results indicate that Tzfp recognizes a sequence-specific motif (tbs) and may play a role in the regulation of the genes carrying the tbs.

  15. New data on seismic wave attenuation in the lithosphere and upper mantle of the northeastern flank of the Baikal rift system

    NASA Astrophysics Data System (ADS)

    Dobrynina, A. A.; Sankov, V. A.; Chechelnitsky, V. V.

    2016-05-01

    The investigation data on seismic wave attenuation in the lithosphere and upper mantle of the northeastern flank of the Baikal rift system obtained with a seismic coda envelope and sliding window are considered. Eleven local districts were described by one-dimensional attenuation models characterized by alternation of high and low attenuation layers, which are consistent with the results obtained previously by Yu.F. Kopnichev for the southwestern flank of the Baikal rift system [9]. The subcrust of the lithosphere contains a thin layer with high attenuation of seismic waves likely related to higher heterogeneity (fragmentation) and occurrence of fluids. The lithosphere basement depth varies from 100-120 km in the west within the Baikal folded area to 120-140 km in the east within the Siberian Platform. It is concluded that there are two asthenosphere layers. Based on specific features of the lithosphere and upper mantle structure, it can be assumed that they were subject to gradual modification involving fluidization processes and partial melting in the Late Cenozoic extension under the influence of distant tectogenesis sources.

  16. Yeast H2A.Z, FACT complex and RSC regulate transcription of tRNA gene through differential dynamics of flanking nucleosomes.

    PubMed

    Mahapatra, Sahasransu; Dewari, Pooran S; Bhardwaj, Anubhav; Bhargava, Purnima

    2011-05-01

    FACT complex is involved in elongation and ensures fidelity in the initiation step of transcription by RNA polymerase (pol) II. Histone variant H2A.Z is found in nucleosomes at the 5'-end of many genes. We report here H2A.Z-chaperone activity of the yeast FACT complex on the short, nucleosome-free, non-coding, pol III-transcribed yeast tRNA genes. On a prototype gene, yeast SUP4, chromatin remodeler RSC and FACT regulate its transcription through novel mechanisms, wherein the two gene-flanking nucleosomes containing H2A.Z, play different roles. Nhp6, which ensures transcription fidelity and helps load yFACT onto the gene flanking nucleosomes, has inhibitory role. RSC maintains a nucleosome abutting the gene terminator downstream, which results in reduced transcription rate in active state while H2A.Z probably helps RSC in keeping the gene nucleosome-free and serves as stress-sensor. All these factors maintain an epigenetic state which allows the gene to return quickly from repressed to active state and tones down the expression from the active SUP4 gene, required probably to maintain the balance in cellular tRNA pool.

  17. Refining the region of branchio-oto-renal syndrome and defining the flanking markers on chromosome 8q by genetic mapping

    SciTech Connect

    Kumar, S.; Kimberling, W.J.; Connolly, C.J.; Tinley, S.; Marres, H.A.M.; Cremers, C.W.R.J.

    1994-12-01

    Branchio-oto-renal syndrome (BOR) is an autosomal dominant disorder associated with external-, middle-, and inner-ear malformations, branchial cleft sinuses, cervical fistulas, mixed hearing loss, and renal anomalies. The gene for BOR was mapped to the long arm of chromosome 8q. Several polymorphic dinucleotide repeat markers were investigated for linkage in two large BOR families, and the region of localization was refined. Two-point linkage analysis yielded the maximum lod scores of 7.44 at {theta} = .03 and 6.71 at {theta} = .04, with markers D8S279 and D8S260, respectively. A multipoint analysis was carried out to position the BOR gene with a defined region using markers D8S165, D8S285, PENK, D8S166, D8S260, D8S279, D8S164, D8S286, D8S84, D8S275, D8S167, D8S273, and D8S271. Haplotype analysis of recombination events at these polymorphic loci was also performed in multigeneration BOR kindreds. The linkage analysis and analysis of recombination events identified markers that clearly flank the BOR locus. The order was determined to be D8S260-BOR-D8S279 at odds > 10{sup 3}:1 over the other possible orders. This flanking markers provide a resource for high-resolution mapping toward cloning and characterizing the BOR gene.

  18. Regulated expression of chimaeric genes containing the 5'-flanking regions of human growth hormone-related genes in transiently transfected rat anterior pituitary tumor cells.

    PubMed Central

    Cattini, P A; Eberhardt, N L

    1987-01-01

    The expression and hormonal regulation of chimaeric genes containing the 5'-flanking regions of the normal human growth hormone (hGH-1), the variant hGH (hGH-2) and chorionic somatomammotropin (hCS-1) genes fused to the chloramphenicol acetyl transferase (CAT) gene has been examined after transient transfection into cultured rat pituitary (GC), and non-pituitary (HeLa and Rat 2) tumor cells. As assessed by levels of CAT activity, the hGH-1 and hCS-1 gene hybrids were expressed at 5- to 25-fold higher levels in GC cells than in HeLa or Rat 2 cells. The hGH-2 gene hybrid was expressed at very low levels in all 3 cell types. Triiodothyronine treatment of transiently transfected GC cells had little effect on CAT activity from the hGH-1 gene hybrid but increased CAT activity from the hCS-1 gene hybrid. A slight but significant increase in CAT expression was detected with both genes after dexamethasone treatment. The data indicate that elements present on the hGH-1 and hCS-1 genes' 5'-flanking DNA are required for the efficient expression of these genes in GC cells. Images PMID:3644237

  19. Mobilized retrotransposon Tos17 of rice by alien DNA introgression transposes into genes and causes structural and methylation alterations of a flanking genomic region.

    PubMed

    Han, F P; Liu, Z L; Tan, M; Hao, S; Fedak, G; Liu, B

    2004-01-01

    Tos17 is a copia-like endogenous retrotransposon of rice, which can be activated by various stresses such as tissue culture and alien DNA introgression. To confirm element mobilization by introgression and to study possible structural and epigenetic effects of Tos17 insertion on its target sequences, we isolated all flanking regions of Tos17 in an introgressed rice line (Tong35) that contains minute amount of genomic DNA from wild rice (Zizania latifolia). It was found that there has been apparent but limited mobilization of Tos17 in this introgression line, as being reflected by increased but stable copy number of the element in progeny of the line. Three of the five activated copies of the element have transposed into genes. Based on sequence analysis and Southern blot hybridization with several double-enzyme digests, no structural change in Tos17 could be inferred in the introgression line. Cytosine methylation status at all seven CCGG sites within Tos17 was also identical between the introgression line and its rice parent (Matsumae)-all sites being heavily methylated. In contrast, changes in structure and cytosine methylation patterns were detected in one of the three low-copy genomic regions that flank newly transposed Tos17, and all changes are stably inherited through selfed generations. PMID:15703040

  20. The relationship between eruptive activity, flank collapse, and sea level at volcanic islands: A long-term (>1 Ma) record offshore Montserrat, Lesser Antilles

    NASA Astrophysics Data System (ADS)

    Coussens, Maya; Wall-Palmer, Deborah; Talling, Peter. J.; Watt, Sebastian. F. L.; Cassidy, Michael; Jutzeler, Martin; Clare, Michael A.; Hunt, James. E.; Manga, Michael; Gernon, Thomas. M.; Palmer, Martin. R.; Hatter, Stuart. J.; Boudon, Georges; Endo, Daisuke; Fujinawa, Akihiko; Hatfield, Robert; Hornbach, Matthew. J.; Ishizuka, Osamu; Kataoka, Kyoko; Le Friant, Anne; Maeno, Fukashi; McCanta, Molly; Stinton, Adam. J.

    2016-07-01

    Hole U1395B, drilled southeast of Montserrat during Integrated Ocean Drilling Program Expedition 340, provides a long (>1 Ma) and detailed record of eruptive and mass-wasting events (>130 discrete events). This record can be used to explore the temporal evolution in volcanic activity and landslides at an arc volcano. Analysis of tephra fall and volcaniclastic turbidite deposits in the drill cores reveals three heightened periods of volcanic activity on the island of Montserrat (˜930 to ˜900 ka, ˜810 to ˜760 ka, and ˜190 to ˜120 ka) that coincide with periods of increased volcano instability and mass-wasting. The youngest of these periods marks the peak in activity at the Soufrière Hills volcano. The largest flank collapse of this volcano (˜130 ka) occurred toward the end of this period, and two younger landslides also occurred during a period of relatively elevated volcanism. These three landslides represent the only large (>0.3 km3) flank collapses of the Soufrière Hills edifice, and their timing also coincides with periods of rapid sea level rise (>5 m/ka). Available age data from other island arc volcanoes suggest a general correlation between the timing of large landslides and periods of rapid sea level rise, but this is not observed for volcanoes in intraplate ocean settings. We thus infer that rapid sea level rise may modulate the timing of collapse at island arc volcanoes, but not in larger ocean-island settings.