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Sample records for 105-r disassembly basin

  1. GROUT TEMPERATURE MEASUREMENTS IN 105-R DISASSEMBLY BASIN D AND E CANAL

    SciTech Connect

    Fogle, R.; Collins, M.; Guerrero, H.

    2010-06-03

    The 105-R Reactor Disassembly Basin Grout Placement Strategy Report (SRNL-TR-2009-00157) identifies various portions of the facility that will undergo an in-situ decommissioning process. The estimated residual radioactive contamination in the 105-R facility is shown in Figure 1. Cementitious grout formulations developed by SRNL are being used to immobilize and isolate the radioactive contamination in existing below grade portions of the 105-R building as shown by the gray-hatched area in Figure 2. A Zero Bleed flowable fill was formulated for both dry placement and for underwater placement. The first major area in the 105-R Disassembly Basin to undergo the grouting process was the D&E Canal and an underlying void space known as the Chase. Grout temperature data was needed to ensure that the grout mix design was on the correct grout curing trajectory to meet the material compressive strength requirement of 50 pounds per square inch. Initial grout temperature measurements were needed to confirm and optimize grout mix design fresh property characteristics; i.e. material strength, and set time. Grout curing temperature is an integrating fresh property characteristic that is used to estimate cementitious material strength in accordance with the Standard Practice for Estimating Concrete Strength by the Maturity Method, ASTM C 1074. The Maturity Method is used in the construction industry to estimate in-place strength of concrete to allow the start of critical construction activities; e.g. formwork removal, removal of cold weather protection, opening of roadways to traffic, etc. Applying this methodology provides an expeditious means to estimate in-place grout strength based on compressive strength laboratory results. The Maturity Method results define the relationship between strength-time and age-time that may be utilized in the field for estimating strength after a given time of placement. Maturation curves were developed under the 105-R Reactor Disassembly Basin

  2. SAVANNAH RIVER SITE R REACTOR DISASSEMBLY BASIN IN SITU DECOMMISSIONING

    SciTech Connect

    Langton, C.; Blankenship, J.; Griffin, W.; Serrato, M.

    2009-12-03

    The US DOE concept for facility in-situ decommissioning (ISD) is to physically stabilize and isolate in tact, structurally sound facilities that are no longer needed for their original purpose of, i.e., generating (reactor facilities), processing(isotope separation facilities) or storing radioactive materials. The 105-R Disassembly Basin is the first SRS reactor facility to undergo the in-situ decommissioning (ISD) process. This ISD process complies with the105-R Disassembly Basin project strategy as outlined in the Engineering Evaluation/Cost Analysis for the Grouting of the R-Reactor Disassembly Basin at the Savannah River Site and includes: (1) Managing residual water by solidification in-place or evaporation at another facility; (2) Filling the below grade portion of the basin with cementitious materials to physically stabilize the basin and prevent collapse of the final cap - Sludge and debris in the bottom few feet of the basin will be encapsulated between the basin floor and overlying fill material to isolate if from the environment; (3) Demolishing the above grade portion of the structure and relocating the resulting debris to another location or disposing of the debris in-place; and (4) Capping the basin area with a concrete slab which is part of an engineered cap to prevent inadvertent intrusion. The estimated total grout volume to fill the 105-R Reactor Disassembly Basin is 24,424 cubic meters or 31,945 cubic yards. Portland cement-based structural fill materials were design and tested for the reactor ISD project and a placement strategy for stabilizing the basin was developed. Based on structural engineering analyses and work flow considerations, the recommended maximum lift height is 5 feet with 24 hours between lifts. Pertinent data and information related to the SRS 105-R-Reactor Disassembly Basin in-situ decommissioning include: regulatory documentation, residual water management, area preparation activities, technology needs, fill material designs

  3. SAVANNAH RIVER SITE R-REACTOR DISASSEMBLY BASIN IN-SITU DECOMMISSIONING -10499

    SciTech Connect

    Langton, C.; Serrato, M.; Blankenship, J.; Griffin, W.

    2010-01-04

    The US DOE concept for facility in-situ decommissioning (ISD) is to physically stabilize and isolate intact, structurally sound facilities that are no longer needed for their original purpose, i.e., generating (reactor facilities), processing(isotope separation facilities) or storing radioactive materials. The 105-R Disassembly Basin is the first SRS reactor facility to undergo the in-situ decommissioning (ISD) process. This ISD process complies with the 105-R Disassembly Basin project strategy as outlined in the Engineering Evaluation/Cost Analysis for the Grouting of the R-Reactor Disassembly Basin at the Savannah River Site and includes: (1) Managing residual water by solidification in-place or evaporation at another facility; (2) Filling the below grade portion of the basin with cementitious materials to physically stabilize the basin and prevent collapse of the final cap - Sludge and debris in the bottom few feet of the basin will be encapsulated between the basin floor and overlying fill material to isolate it from the environment; (3) Demolishing the above grade portion of the structure and relocating the resulting debris to another location or disposing of the debris in-place; and (4) Capping the basin area with a concrete slab which is part of an engineered cap to prevent inadvertent intrusion. The estimated total grout volume to fill the 105-R Reactor Disassembly Basin is 24,384 cubic meters or 31,894 cubic yards. Portland cement-based structural fill materials were designed and tested for the reactor ISD project, and a placement strategy for stabilizing the basin was developed. Based on structural engineering analyses and material flow considerations, maximum lift heights and differential height requirements were determined. Pertinent data and information related to the SRS 105-R Reactor Disassembly Basin in-situ decommissioning include: regulatory documentation, residual water management, area preparation activities, technology needs, fill material

  4. Highly Selective Nuclide Removal from the R-Reactor Disassembly Basin at the SRS

    SciTech Connect

    Pickett, J. B.; Austin, W. E.; Dukes, H. H.

    2002-02-26

    This paper describes the results of a deployment of highly selective ion-exchange resin technologies for the in-situ removal of Cs-137 and Sr-90 from the Savannah River Site (SRS) R-Reactor Disassembly Basin. The deployment was supported by the DOE Office of Science and Technology's (OST, EM-50) National Engineering Technology Laboratory (NETL), as a part of an Accelerated Site Technology Deployment (ASTD) project. The Facilities Decontamination and Decommissioning (FDD) Program at the SRS conducted this deployment as a part of an overall program to deactivate three of the site's five reactor disassembly basins.

  5. A Summary Report on the NPH Evaluation of 105-L Disassembly Basin

    SciTech Connect

    Joshi, J.R.

    2002-04-30

    The L Area Disassembly Basin (LDB) is evaluated for the natural phenomena hazards (NPH) effects due to earthquake, wind, and tornado in accordance with DOE Order 420.1 and DOE-STD-1020. The deterministic analysis is performed for a Performance Category 3 (PC3) level of loads. Savannah River Site (SRS) specific NPH loads and design criteria are obtained from Engineering Standard 01060. It is demonstrated that the demand to capacity (D/C) ratios for primary and significant structural elements are acceptable (equal to or less than 1.0). Thus, 105-L Disassembly Basin building structure is qualified for the PC3 NPH effects in accordance with DOE Order 420.1.

  6. Distribution Coefficients (Kd Values) for Waste Resins Generated from the K and L Disassembly Basin Facilities

    SciTech Connect

    Kaplan, D.I.

    2002-12-02

    The objective of this study was to measure 14C, 129I, and 99Tc Kd values of spent resin generated from the K and L Disassembly Basin Facilities. The scope of the work was to conduct Kd measurements of resins combined in the ratio that they are disposed, 42:58 cation:anion. Because it was not known how these spent resins would be buried, it was necessary to measure the Kd values in such a manner as to simulate both trench and vault disposal. This was accomplished by using an acid-rain simulant (a standard U.S. Environmental Protection Agency protocol) and a cement leachate simulant .

  7. Technical review of WSRC-TR-93-614 criticality safety evaluation for disassembly basin sand filter

    SciTech Connect

    Reed, R.L

    1994-04-27

    The study documented in WSRC-TR-93-614 performed an evaluation of the criticality potential associated with the Disassembly Basin Sand Filter for K and L Areas. The document reviewed incorporated results of calculations documented in the engineering calculation N-CLC-K-00151. Analyses of the contents of disassembly basin sludge has indicated that the sludge contains fissile material in excess of subcritical mass limits as specified in ANSI/ANS standards. Previous studies had determined that the fissile material can not collect into a critical configuration in the basin. Since the sand filter is intended to remove suspended particles from the basin water and could serve as a mechanism to collect the fissile material into a critical configuration, the study examined conditions under which criticality could occur in the sand filter. The study shows that criticality is not considered possible in the sand filter. This review emphasized the technical accuracy and presentation of the evaluation. The evaluation was also examined for the elements required for NCSEs. The review was performed in accordance with the NRTSC technical review requirements and procedures and the E7 Manual technical review requirements. The technical review (per the E7 manual) of the engineering calculation (N-CLC-K-0 1 5 1) was previously performed by this reviewer.

  8. Determination of C0-60 in Cobalt Slugs and Slabs and Radionuclides in Curium Sampler Slugs L-Reactor Disassembly Basin

    SciTech Connect

    Casella, V.R.

    2004-01-23

    Co-60 was historically produced in the SRS reactors. Cobalt slugs were irradiated in the early 1970s. Post-production, remaining cobalt slugs (including slab form) were consolidated for storage. There are approximately nine hundred cobalt slugs currently stored awaiting final disposition. These slugs had historically incomplete documentation for activity rates; therefore, assaying was required in order to determine their activity levels. Since the gamma dose rate from these slugs is extremely high, the most cost effective way to shield a source of this magnitude from personnel and the radiation detector was to use the basin water in which the slugs are stored as the shield. A sodium iodide gamma detector was placed above a specially designed air collimator assembly, so that slug was at least eight feet from the detector and was shielded by the basin water. Using a sodium iodide detector and multichannel analyzer system and an underwater collimator assembly, Co-60 concentrations we re determined for Disassembly Basin cobalt slugs and slabs and 18 curium sampler slugs. The total activity of all of the assayed slugs summed to 31,783 curies. From the Co-60 concentrations of the curium sampler slugs, the irradiation flux was determined for the known irradiation time. The amounts of Pu-238, 239, 240, 241, 242; Am-241, 243; and Cm-242, 244 produced were then obtained based on the original amount of Pu-239 irradiated.

  9. Pit disassembly motion control

    SciTech Connect

    Christensen, L.; Pittman, P. C.

    2001-01-01

    A Department of Energy (DOE) Pit Disassembly and Conversion Facility (PDCF) is being designed for the Savannah River Site in South Carolina. The facility will recover plutonium from excess nuclear weapon pits defined in START II and START III treaties. The plutonium will be stored and used to produce mixed oxide reactor fuel at another new DOE facility. Because of radiation dose issues, much of the pit disassembly work and material transfer will be automated. Automated material handling systems will interface with disassembly lathes, conversion reactors that produce oxide for storage, robotic container welding stations, vault retrieval systems, and nondestructive assay (NDA) instrumentation. The goal is to use common motion control hardware for material transfer and possibly common motion controllers for the unique PDCF systems. The latter is complicated by the different directions manufactures are considering for distributed control, such as Firewire, SERCOS, etc., and by the unique control requirements of machines such as lathes compared to controls for an integrated NDA system. The current design approach is to standardize where possible, use network cables to replace wire bundles where possible, but to first select hardware and motion controllers that meet specific machine or process requirements.

  10. AGC-2 Disassembly Report

    SciTech Connect

    William Windes

    2014-05-01

    The Next Generation Nuclear Plant (NGNP) Graphite Research and Development (R&D) Program is currently measuring irradiated material properties for predicting the behavior and operating performance of new nuclear graphite grades available for use within the cores of new very high temperature reactor designs. The Advanced Graphite Creep (AGC) experiment, consisting of six irradiation capsules, will generate irradiated graphite performance data for NGNP reactor operating conditions. The AGC experiment is designed to determine the changes to specific material properties such as thermal diffusivity, thermal expansion, elastic modulus, mechanical strength, irradiation induced dimensional change rate, and irradiation creep for a wide variety of nuclear grade graphite types over a range of high temperature, and moderate doses. A series of six capsules containing graphite test specimens will be used to expose graphite test samples to a dose range from 1 to 7 dpa at three different temperatures (600, 900, and 1200°C) as described in the Graphite Technology Development Plan. Since irradiation induced creep within graphite components is considered critical to determining the operational life of the graphite core, some of the samples will also be exposed to an applied load to determine the creep rate for each graphite type under both temperature and neutron flux. All six AGC capsules in the experiment will be irradiated in the Advanced Test Reactor (ATR). AGC-1 and AGC-2 will be irradiated in the south flux trap and AGC-3–AGC-6 will be irradiated in the east flux trap. The change in flux traps is due to NGNP irradiation priorities requiring the AGC experiment to be moved to accommodate Fuel irradiation experiments. After irradiation, all six AGC capsules will be cooled in the ATR Canal, sized for shipment, and shipped to the Materials and Fuels Complex (MFC) where the capsule will be disassembled in the Hot Fuel Examination Facility (HFEF). During disassembly, the metallic

  11. Static Detection of Disassembly Errors

    SciTech Connect

    Krishnamoorthy, Nithya; Debray, Saumya; Fligg, Alan K

    2009-10-13

    Static disassembly is a crucial first step in reverse engineering executable files, and there is a consider- able body of work in reverse-engineering of binaries, as well as areas such as semantics-based security anal- ysis, that assumes that the input executable has been correctly disassembled. However, disassembly errors, e.g., arising from binary obfuscations, can render this assumption invalid. This work describes a machine- learning-based approach, using decision trees, for stat- ically identifying possible errors in a static disassem- bly; such potential errors may then be examined more closely, e.g., using dynamic analyses. Experimental re- sults using a variety of input executables indicate that our approach performs well, correctly identifying most disassembly errors with relatively few false positives.

  12. Partial disassembly of peroxisomes

    PubMed Central

    1985-01-01

    Rat liver peroxisomes were subjected to a variety of procedures intended to partially disassemble or damage them; the effects were analyzed by recentrifugation into sucrose gradients, enzyme analyses, electron microscopy, and SDS PAGE. Freezing and thawing or mild sonication released some matrix proteins and produced apparently intact peroxisomal "ghosts" with crystalloid cores and some fuzzy fibrillar content. Vigorous sonication broke open the peroxisomes but the membranes remained associated with cores and fibrillar and amorphous matrix material. The density of both ghosts and more severely damaged peroxisomes was approximately 1.23. Pyrophosphate (pH 9) treatment solubilized the fibrillar content, yielding ghosts that were empty except for cores. Some matrix proteins such as catalase and thiolase readily leak from peroxisomes. Other proteins were identified that remain in mechanically damaged peroxisomes but are neither core nor membrane proteins because they can be released by pyrophosphate treatment. These constitute a class of poorly soluble matrix proteins that appear to correspond to the fibrillar material observed morphologically. All of the peroxisomal beta-oxidation enzymes are located in the matrix, but they vary greatly in how easily they leak out. Palmitoyl coenzyme A synthetase is in the membrane, based on its co-distribution with the 22-kilodalton integral membrane polypeptide. PMID:2989301

  13. First insights into disassembled "evapotranspiration"

    NASA Astrophysics Data System (ADS)

    Chormański, Jarosław; Kleniewska, Małgorzata; Berezowski, Tomasz; Szporak-Wasilewska, Sylwia; Okruszko, Tomasz; Szatyłowicz, Jan; Batelaan, Okke

    2015-04-01

    In this work we present an initial data analysis obtained from a complex tool for measuring water fluxes in wetland ecosystems. The tool was designed to quantify processes related to interception storage on plants leafs. The measurements are conducted by combining readings from various instruments, including: eddy covariance tower (EC), field spectrometer, SapFlow system, rain gauges above and under canopy, soil moisture probes and other. The idea of this set-up is to provide continuous measurement of overall water flux from the ecosystem (EC tower), intercepted water volume and timing (field spectrometers), through-fall (rain gauges above and under canopy), transpiration (SapFlow), evaporation and soil moisture (soil moisture probes). Disassembling the water flux to the above components allows giving more insight to the interception related processes and differentiates them fromthe total evapotranspiration. The measurements are conducted in the Upper Biebrza Basin (NE Poland). The study area is part of the valley and is covered by peat soils (mainly peat moss with the exception of areas near the river) and receives no inundations waters of the Biebrza. The plant community of Agrostietum-Carici caninae has a dominant share here creating an up to 0.6 km wide belt along the river. The area is covered also by Caricion lasiocarpae as well as meadows and pastures Molinio-Arrhenatheretea, Phragmitetum communis. Sedges form a hummock pattern characteristic for the sedge communities in natural river valleys with wetland vegetation. The main result of the measurement set-up will be the analyzed characteristics and dynamics of interception storage for sedge ecosystems and a developed methodology for interception monitoring by use spectral reflectance technique. This will give a new insight to processes of evapotranspiration in wetlands and its component transpiration, evaporation from interception and evaporation from soil. Moreover, other important results of this project

  14. CALUTRON ASSEMBLING AND DISASSEMBLING MEANS

    DOEpatents

    Andrews, R.E.; Thornton, J.

    1959-01-27

    This patent relates to the assembling and disassembling of a calutron and, more specifically describes a calutron having the ion separating mechanism carried by a fuce plate removably secured to the tank. When it is desired to withdraw the ion separating mechanism from the tank, a motor is energized and a carriage attached through a bracket to the fuce plate is driven along a track. The face plate moves out from the tank in substantially a linear direction, preventing injury to the ion separating mechanism.

  15. 19 CFR 181.132 - Disassembly.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false Disassembly. 181.132 Section 181.132 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) NORTH AMERICAN FREE TRADE AGREEMENT Rules of Origin § 181.132 Disassembly. (a) Treated...

  16. 19 CFR 181.132 - Disassembly.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 2 2012-04-01 2012-04-01 false Disassembly. 181.132 Section 181.132 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) NORTH AMERICAN FREE TRADE AGREEMENT Rules of Origin § 181.132 Disassembly. (a) Treated...

  17. 19 CFR 181.132 - Disassembly.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 2 2013-04-01 2013-04-01 false Disassembly. 181.132 Section 181.132 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) NORTH AMERICAN FREE TRADE AGREEMENT Rules of Origin § 181.132 Disassembly. (a) Treated...

  18. 19 CFR 181.132 - Disassembly.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Disassembly. 181.132 Section 181.132 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) NORTH AMERICAN FREE TRADE AGREEMENT Rules of Origin § 181.132 Disassembly. (a) Treated...

  19. Modeling operational behavior of a disassembly line

    NASA Astrophysics Data System (ADS)

    Kizilkaya, Elif A.; Gupta, Surendra M.

    2004-12-01

    In this paper we present a dynamic kanban (pull) system specifically developed for disassembly lines. This type of kanban system is much more complex than the traditional kanban system used in assembly lines. For instance, unlike the assembly line where the external demand occurs only at the last station, the demands in the disassembly case also occur at any of the intermittent stations. The reason is that as a product moves on the disassembly line, various parts are disassembled at every station and accumulated at that station. Therefore, there are as many demand sources as there are number of parts. We consider a case example involving the end-of-life products. Based on the precedence relationships and other criteria such as hazardous properties of the parts, we balance the disassembly line. The results of the disassembly line-balancing problem (DLBP) are used as input to the proposed dynamic kanban system for disassembly line (DKSDL). We compare the performance of the DKSDL to the modified kanban system for disassembly line (MKSDL), which was previously introduced by the authors. We show, via simulation, that the DKSDL is far superior to MKSDL considered.

  20. Disassembling iron availability to phytoplankton.

    PubMed

    Shaked, Yeala; Lis, Hagar

    2012-01-01

    The bioavailability of iron to microorganisms and its underlying mechanisms have far reaching repercussions to many natural systems and diverse fields of research, including ocean biogeochemistry, carbon cycling and climate, harmful algal blooms, soil and plant research, bioremediation, pathogenesis, and medicine. Within the framework of ocean sciences, short supply and restricted bioavailability of Fe to phytoplankton is thought to limit primary production and curtail atmospheric CO(2) drawdown in vast ocean regions. Yet a clear-cut definition of bioavailability remains elusive, with elements of iron speciation and kinetics, phytoplankton physiology, light, temperature, and microbial interactions, to name a few, all intricately intertwined into this concept. Here, in a synthesis of published and new data, we attempt to disassemble the complex concept of iron bioavailability to phytoplankton by individually exploring some of its facets. We distinguish between the fundamentals of bioavailability - the acquisition of Fe-substrate by phytoplankton - and added levels of complexity involving interactions among organisms, iron, and ecosystem processes. We first examine how phytoplankton acquire free and organically bound iron, drawing attention to the pervasiveness of the reductive uptake pathway in both prokaryotic and eukaryotic autotrophs. Turning to acquisition rates, we propose to view the availability of various Fe-substrates to phytoplankton as a spectrum rather than an absolute "all or nothing." We then demonstrate the use of uptake rate constants to make comparisons across different studies, organisms, Fe-compounds, and environments, and for gaging the contribution of various Fe-substrates to phytoplankton growth in situ. Last, we describe the influence of aquatic microorganisms on iron chemistry and fate by way of organic complexation and bio-mediated redox transformations and examine the bioavailability of these bio-modified Fe species.

  1. Disassembling Iron Availability to Phytoplankton

    PubMed Central

    Shaked, Yeala; Lis, Hagar

    2012-01-01

    The bioavailability of iron to microorganisms and its underlying mechanisms have far reaching repercussions to many natural systems and diverse fields of research, including ocean biogeochemistry, carbon cycling and climate, harmful algal blooms, soil and plant research, bioremediation, pathogenesis, and medicine. Within the framework of ocean sciences, short supply and restricted bioavailability of Fe to phytoplankton is thought to limit primary production and curtail atmospheric CO2 drawdown in vast ocean regions. Yet a clear-cut definition of bioavailability remains elusive, with elements of iron speciation and kinetics, phytoplankton physiology, light, temperature, and microbial interactions, to name a few, all intricately intertwined into this concept. Here, in a synthesis of published and new data, we attempt to disassemble the complex concept of iron bioavailability to phytoplankton by individually exploring some of its facets. We distinguish between the fundamentals of bioavailability – the acquisition of Fe-substrate by phytoplankton – and added levels of complexity involving interactions among organisms, iron, and ecosystem processes. We first examine how phytoplankton acquire free and organically bound iron, drawing attention to the pervasiveness of the reductive uptake pathway in both prokaryotic and eukaryotic autotrophs. Turning to acquisition rates, we propose to view the availability of various Fe-substrates to phytoplankton as a spectrum rather than an absolute “all or nothing.” We then demonstrate the use of uptake rate constants to make comparisons across different studies, organisms, Fe-compounds, and environments, and for gaging the contribution of various Fe-substrates to phytoplankton growth in situ. Last, we describe the influence of aquatic microorganisms on iron chemistry and fate by way of organic complexation and bio-mediated redox transformations and examine the bioavailability of these bio-modified Fe species. PMID:22529839

  2. Generation of control sequences for a pilot-disassembly system

    NASA Astrophysics Data System (ADS)

    Seliger, Guenther; Kim, Hyung-Ju; Keil, Thomas

    2002-02-01

    Closing the product and material cycles has emerged as a paradigm for industry in the 21st century. Disassembly plays a key role in a life cycle economy since it enables the recovery of resources. A partly automated disassembly system should adapt to a large variety of products and different degrees of devaluation. Also the amounts of products to be disassembled can vary strongly. To cope with these demands an approach to generate on-line disassembly control sequences will be presented. In order to react on these demands the technological feasibility is considered within a procedure for the generation of disassembly control sequences. Procedures are designed to find available and technologically feasible disassembly processes. The control system is formed by modularised and parameterised control units in the cell level within the entire control architecture. In the first development stage product and process analyses at the sample product washing machine were executed. Furthermore a generalized disassembly process was defined. Afterwards these processes were structured in primary and secondary functions. In the second stage the disassembly control at the technological level was investigated. Factors were the availability of the disassembly tools and the technological feasibility of the disassembly processes within the disassembly system. Technical alternative disassembly processes are determined as a result of availability of the tools and technological feasibility of processes. The fourth phase was the concept for the generation of the disassembly control sequences. The approach will be proved in a prototypical disassembly system.

  3. Combinatorial optimization methods for disassembly line balancing

    NASA Astrophysics Data System (ADS)

    McGovern, Seamus M.; Gupta, Surendra M.

    2004-12-01

    Disassembly takes place in remanufacturing, recycling, and disposal with a line being the best choice for automation. The disassembly line balancing problem seeks a sequence which: minimizes workstations, ensures similar idle times, and is feasible. Finding the optimal balance is computationally intensive due to factorial growth. Combinatorial optimization methods hold promise for providing solutions to the disassembly line balancing problem, which is proven to belong to the class of NP-complete problems. Ant colony optimization, genetic algorithm, and H-K metaheuristics are presented and compared along with a greedy/hill-climbing heuristic hybrid. A numerical study is performed to illustrate the implementation and compare performance. Conclusions drawn include the consistent generation of optimal or near-optimal solutions, the ability to preserve precedence, the speed of the techniques, and their practicality due to ease of implementation.

  4. Electronic waste disassembly with industrial waste heat.

    PubMed

    Chen, Mengjun; Wang, Jianbo; Chen, Haiyian; Ogunseitan, Oladele A; Zhang, Mingxin; Zang, Hongbin; Hu, Jiukun

    2013-01-01

    Waste printed circuit boards (WPCBs) are resource-rich but hazardous, demanding innovative strategies for post-consumer collection, recycling, and mining for economically precious constituents. A novel technology for disassembling electronic components from WPCBs is proposed, using hot air to melt solders and to separate the components and base boards. An automatic heated-air disassembling equipment was designed to operate at a heating source temperature at a maximum of 260 °C and an inlet pressure of 0.5 MPa. A total of 13 individual WPCBs were subjected to disassembling tests at different preheat temperatures in increments of 20 °C between 80 and 160 °C, heating source temperatures ranging from 220 to 300 °C in increments of 20 °C, and incubation periods of 1, 2, 4, 6, or 8 min. For each experimental treatment, the disassembly efficiency was calculated as the ratio of electronic components released from the board to the total number of its original components. The optimal preheat temperature, heating source temperature, and incubation period to disassemble intact components were 120 °C, 260 °C, and 2 min, respectively. The disassembly rate of small surface mount components (side length ≤ 3 mm) was 40-50% lower than that of other surface mount components and pin through hole components. On the basis of these results, a reproducible and sustainable industrial ecological protocol using steam produced by industrial exhaust heat coupled to electronic-waste recycling is proposed, providing an efficient, promising, and green method for both electronic component recovery and industrial exhaust heat reutilization.

  5. Microtubules regulate disassembly of epithelial apical junctions

    PubMed Central

    Ivanov, Andrei I; McCall, Ingrid C; Babbin, Brian; Samarin, Stanislav N; Nusrat, Asma; Parkos, Charles A

    2006-01-01

    Background Epithelial tight junction (TJ) and adherens junction (AJ) form the apical junctional complex (AJC) which regulates cell-cell adhesion, paracellular permeability and cell polarity. The AJC is anchored on cytoskeletal structures including actin microfilaments and microtubules. Such cytoskeletal interactions are thought to be important for the assembly and remodeling of apical junctions. In the present study, we investigated the role of microtubules in disassembly of the AJC in intestinal epithelial cells using a model of extracellular calcium depletion. Results Calcium depletion resulted in disruption and internalization of epithelial TJs and AJs along with reorganization of perijunctional F-actin into contractile rings. Microtubules reorganized into dense plaques positioned inside such F-actin rings. Depolymerization of microtubules with nocodazole prevented junctional disassembly and F-actin ring formation. Stabilization of microtubules with either docetaxel or pacitaxel blocked contraction of F-actin rings and attenuated internalization of junctional proteins into a subapical cytosolic compartment. Likewise, pharmacological inhibition of microtubule motors, kinesins, prevented contraction of F-actin rings and attenuated disassembly of apical junctions. Kinesin-1 was enriched at the AJC in cultured epithelial cells and it also accumulated at epithelial cell-cell contacts in normal human colonic mucosa. Furthermore, immunoprecipitation experiments demonstrated association of kinesin-1 with the E-cadherin-catenin complex. Conclusion Our data suggest that microtubules play a role in disassembly of the AJC during calcium depletion by regulating formation of contractile F-actin rings and internalization of AJ/TJ proteins. PMID:16509970

  6. Multi-kanban mechanism for appliance disassembly

    NASA Astrophysics Data System (ADS)

    Udomsawat, Gun; Gupta, Surendra M.

    2005-11-01

    The use of household appliances continues to rise every year. A significant number of End-Of-Life (EOL) appliances are generated because of the introduction of newer models that are more attractive, efficient and affordable. Others are, of course, generated when they become non-functional. Many regulations encourage recycling of EOL appliances to reduce the amount of waste sent to landfills. In addition, EOL appliances offer the appliance manufacturing and remanufacturing industries a source of less expensive raw materials and components. For this reason product recovery has become a subject of interest during the past decade. In this paper, we study the disassembly line for appliance disassembly. We discuss and incorporate some of the complications that are inherent in disassembly line including product arrival, demand arrival, inventory fluctuation and production control mechanisms. We show how to overcome such complications by implementing a multi-kanban system in the appliance disassembly line setting. The multi-kanban system (MKS) relies on dynamic routing of kanbans according to the state of the system. We investigate the multi-kanban mechanism using simulation and explore the effect of product mix on performance of the traditional push system (TPS) and MKS in terms of controlling the system's inventory while attempting to achieve a decent customer service level.

  7. LLNL Torso Phantom Assembly and Disassembly

    SciTech Connect

    Hickman, D P

    2005-10-05

    This document from the LLNL In Vivo measurement Facility archives provides important historical as well as current methods for the proper handling of the LLNL Torso Phantom. This document was written circa 1980 and is intended for use by in vivo measurement facilities that perform calibrations using the LLNL Torso Phantom. Proper care and use of the LLNL Torso Phantom will greatly extend the useful lifetime of the phantom. The assembly, and disassembly of the Realistic Phantom are simple tasks and are, for the most part, self evident. However, there are some considerations that will make these tasks easier and assure long life of the parts. The assembly process is presented in Figures 1 through 9 while disassembly suggestions are illustrated in Figures 10 and 11.

  8. BASINS

    EPA Pesticide Factsheets

    Better Assessment Science Integrating Point and Nonpoint Sources (BASINS) is a multipurpose environmental analysis system designed to help regional, state, and local agencies perform watershed- and water quality-based studies.

  9. Multikanban model for disassembly line with demand fluctuation

    NASA Astrophysics Data System (ADS)

    Udomsawat, Gun; Gupta, Surendra M.; Al-Turki, Yousef A. Y.

    2004-02-01

    In recent years, the continuous growth in consumer waste and dwindling natural resources has seriously threatened the environment. Realizing this, several countries have passed regulations that force manufacturers not only to manufacture environmentally conscious products, but also to take back their used products from consumers so that the components and materials recovered from the products may be reused and/or recycled. Disassembly plays an important role in product recovery. A disassembly line is perhaps the most suitable setting for disassembly of products in large quantities. Because a disassembly line has a tendency to generate excessive inventory, employing a kanban system can reduce the inventory level and let the system run more efficiently. A disassembly line is quite different from an assembly line. For example, not only can the demand arrive at the last station, it can also arrive at any of the other stations in the system. The demand for a component on the disassembly line could fluctuate widely. In fact, there are many other complicating matters that need to be considered to implement the concept of kanbans in such an environment. In this paper, we discuss the complications that are unique to a disassembly line. We discuss the complications in utilizing the conventional production control mechanisms in a disassembly line setting. We then show how to overcome them by implementing kanbans in a disassembly line setting with demand fluctuation and introduce the concept of multi-kanban mechanism. We demonstrate its effectiveness using a simulation model. An example is presented to illustrate the concept.

  10. Disassembly sequencing problem: a case study of a cell phone

    NASA Astrophysics Data System (ADS)

    Gupta, Surendra M.; Erbis, Evren; McGovern, Seamus M.

    2004-12-01

    Selection of an optimal disassembly sequence is essential for the efficient processing of a product at the end of its life. Disassembly sequences are listings of disassembly actions (such as the separation of an assembly into two or more subassemblies, or removing one or more connections between components). Disassembly takes place in remanufacturing, recycling, and disposal with a disassembly line being the best choice for automation. In this paper, the disassembly sequencing problem is solved for a cell phone case on a disassembly line, seeking a sequence which is feasible, minimizes the number of workstations (and hence idle times), provides for early removal of high demand/value parts, provides the removal of parts that lead to the access of greatest number of still-installed parts, and early removal of hazardous parts as well as for the grouping of parts for removal having identical part removal directions. Since finding the optimal sequence is computationally intensive due to factorial growth, a heuristic method is used taking into account various disassembly-specific matters. Using the experimentally determined precedence relationships and task times of a real-world cell phone, a MATLAB program is designed and a sequencing solution is generated. Finally, Design for Disassembly (DFD) improvements are recommended with respect to environmentally conscious manufacturing.

  11. A Heuristic for Disassembly Planning in Remanufacturing System

    PubMed Central

    2014-01-01

    This study aims to improve the efficiency of disassembly planning in remanufacturing environment. Even though disassembly processes are considered as the reverse of the corresponding assembly processes, under some technological and management constraints the feasible and efficient disassembly planning can be achieved by only well-designed algorithms. In this paper, we propose a heuristic for disassembly planning with the existence of disassembled part/subassembly demands. A mathematical model is formulated for solving this problem to determine the sequence and quantity of disassembly operations to minimize the disassembly costs under sequence-dependent setup and capacity constraints. The disassembly costs consist of the setup cost, part inventory holding cost, disassembly processing cost, and purchasing cost that resulted from unsatisfied demand. A simple but efficient heuristic algorithm is proposed to improve the quality of solution and computational efficiency. The main idea of heuristic is to divide the planning horizon into the smaller planning windows and improve the computational efficiency without much loss of solution quality. Performances of the heuristic are investigated through the computational experiments. PMID:24895679

  12. Postulated accident scenarios in weapons disassembly

    SciTech Connect

    Payne, S.S.

    1997-06-01

    A very brief summary of three postulated accident scenarios for weapons disassembly is provided in the paper. The first deals with a tetrahedral configuration of four generic pits; the second, an infinite planar array of generic pits with varying interstitial water density; and the third, a spherical shell with internal mass suspension in water varying the size and mass of the shell. Calculations were performed using the Monte Carlo Neutron Photon transport code MCNP4A. Preliminary calculations pointed to a need for higher resolution of small pit separation regimes and snapshots of hydrodynamic processes of water/plutonium mixtures.

  13. Impact of different disassembly line balancing algorithms on the performance of dynamic kanban system for disassembly line

    NASA Astrophysics Data System (ADS)

    Kizilkaya, Elif A.; Gupta, Surendra M.

    2005-11-01

    In this paper, we compare the impact of different disassembly line balancing (DLB) algorithms on the performance of our recently introduced Dynamic Kanban System for Disassembly Line (DKSDL) to accommodate the vagaries of uncertainties associated with disassembly and remanufacturing processing. We consider a case study to illustrate the impact of various DLB algorithms on the DKSDL. The approach to the solution, scenario settings, results and the discussions of the results are included.

  14. Asymmetric disassembly and robustness in declining networks

    PubMed Central

    Saavedra, Serguei; Reed-Tsochas, Felix; Uzzi, Brian

    2008-01-01

    Mechanisms that enable declining networks to avert structural collapse and performance degradation are not well understood. This knowledge gap reflects a shortage of data on declining networks and an emphasis on models of network growth. Analyzing >700,000 transactions between firms in the New York garment industry over 19 years, we tracked this network's decline and measured how its topology and global performance evolved. We find that favoring asymmetric (disassortative) links is key to preserving the topology and functionality of the declining network. Based on our findings, we tested a model of network decline that combines an asymmetric disassembly process for contraction with a preferential attachment process for regrowth. Our simulation results indicate that the model can explain robustness under decline even if the total population of nodes contracts by more than an order of magnitude, in line with our observations for the empirical network. These findings suggest that disassembly mechanisms are not simply assembly mechanisms in reverse and that our model is relevant to understanding the process of decline and collapse in a broad range of biological, technological, and financial networks. PMID:18936489

  15. 2-opt heuristic for the disassembly line balancing problem

    NASA Astrophysics Data System (ADS)

    McGovern, Seamus M.; Gupta, Surendra M.

    2004-02-01

    Disassembly activities are an important part of product recovery operations. The disassembly line is the best choice for automated disassembly of returned products. However, finding the optimal balance for a disassembly line is computationally intensive with exhaustive search quickly becoming prohibitively large. In this paper, a greedy algorithm is presented for obtaining optimal or near-optimal solutions to the disassembly line-balancing problem. The greedy algorithm is a first-fit decreasing algorithm further enhanced to preserve precedence relationships. The algorithm seeks to minimize the number of workstations while addressing hazardous and high demand components. A two optimal algorithm is then developed to balance the part removal sequence and attempt to further reduce the total number of workstations. Examples are considered to illustrate the methodology. The conclusions drawn from the study include the consistent generation of optimal or near-optimal solutions, the ability to preserve precedence, the speed of the algorithms and their practicality due to the ease of implementation.

  16. Alignment Pins for Assembling and Disassembling Structures

    NASA Technical Reports Server (NTRS)

    Campbell, Oliver C.

    2008-01-01

    Simple, easy-to-use, highly effective tooling has been devised for maintaining alignment of bolt holes in mating structures during assembly and disassembly of the structures. The tooling was originally used during removal of a body flap from the space shuttle Atlantis, in which misalignments during removal of the last few bolts could cause the bolts to bind in their holes. By suitably modifying the dimensions of the tooling components, the basic design of the tooling can readily be adapted to other structures that must be maintained in alignment. The tooling includes tapered, internally threaded alignment pins designed to fit in the bolt holes in one of the mating structures, plus a draw bolt and a cup that are used to install or remove each alignment pin. In preparation for disassembly of two mating structures, external supports are provided to prevent unintended movement of the structures. During disassembly of the structures, as each bolt that joins the structures is removed, an alignment pin is installed in its place. Once all the bolts have been removed and replaced with pins, the pins maintain alignment as the structures are gently pushed or pulled apart on the supports. In assembling the two structures, one reverses the procedure described above: pins are installed in the bolt holes, the structures are pulled or pushed together on the supports, then the pins are removed and replaced with bolts. The figure depicts the tooling and its use. To install an alignment pin in a bolt hole in a structural panel, the tapered end of the pin is inserted from one side of the panel, the cup is placed over the pin on the opposite side of the panel, the draw bolt is inserted through the cup and threaded into the pin, the draw bolt is tightened to pull the pin until the pin is seated firmly in the hole, then the draw bolt and cup are removed, leaving the pin in place. To remove an alignment pin, the cup is placed over the pin on the first-mentioned side of the panel, the draw

  17. Montmorillonite-induced Bacteriophage φ6 Disassembly

    NASA Astrophysics Data System (ADS)

    Trusiak, A.; Gottlieb, P.; Katz, A.; Alimova, A.; Steiner, J. C.; Block, K. A.

    2012-12-01

    It is estimated that there are 1031 virus particles on Earth making viruses an order of magnitude more prevalent in number than prokaryotes with the vast majority of viruses being bacteriophages. Clays are a major component of soils and aquatic sediments and can react with RNA, proteins and bacterial biofilms. The clays in soils serve as an important moderator between phage and their host bacteria, helping to preserve the evolutionary balance. Studies on the effects of clays on viral infectivity have given somewhat contradictory results; possibly a consequence of clay-virus interactions being dependent on the unique structure of particular viruses. In this work, the interaction between montmorillonite and the bacteriophage φ6 is investigated. φ6 is a member of the cystovirus family that infects Pseudomonas syringe, a common plant pathogen. As a member of the cystovirus family with an enveloped structure, φ6 serves as a model for reoviruses, a human pathogen. Experiments were conducted with φ6 suspended in dilute, purified homoionic commercial-grade montmorillonite over a range of virus:clay ratios. At a 1:100000 virus:clay ratio, the clay reduced viral infectivity by 99%. The minimum clay to virus ratio which results in a measurable reduction of P. syringae infection is 1:1. Electron microscopy demonstrates that mixed suspensions of smectite and virus co-aggregate to form flocs encompassing virions within the smectite. Both free viral particles as well as those imbedded in the flocs are seen in the micrographs to be missing the envelope- leaving only the nucleocapsid (NC) intact; indicating that smectite inactivates the virus by envelope disassembly. These results have strong implications in the evolution of both the φ6 virus and its P. syringae host cells. TEM of aggregate showing several disassembled NCs.

  18. Disassembly line balancing with limited supply and subassembly availability

    NASA Astrophysics Data System (ADS)

    Altekin, Fatma Tevhide; Kandiller, Levent; Ozdemirel, Nur Evin

    2004-02-01

    Disassembly line balancing problem (DLBP) aims at finding a feasible assignment of disassembly tasks to workstations such that precedence relations among tasks are satisfied and some measure of effectiveness is optimized. We consider partial disassembly under limited supply of a single product as well as availability of its subassemblies. Hence, in satisfying the demand for revenue generating parts, both discarded products and available subassemblies can be utilized. We assume that part revenues and demand, task times and costs, inventory holding costs, and station opening costs are given. We propose two DLBP formulations. The first one maximizes the profit per disassembly cycle. The second formulation maximizes the profit over the whole planning horizon. Proposed formulations and computational results are presented.

  19. New package for Belleville spring permits rate change, easy disassembly

    NASA Technical Reports Server (NTRS)

    Mac Glashan, W. F.

    1964-01-01

    A spring package, with grooves to hold the spring washers at the inner and outer edges, reduces hysteresis to a minimum. Three-segment retainers permit easy disassembly so that the spring rate can be changed.

  20. 12. View of disassembled steam engine sitting in open shed ...

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

    12. View of disassembled steam engine sitting in open shed showing base, columns and entablature. - Hacienda Azucarera La Esperanza, Steam Engine & Mill, 2.65 Mi. N of PR Rt. 2 Bridge over Manati River, Manati, Manati Municipio, PR

  1. 13. View of disassembled steam engine showing cylinder, piston rod, ...

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

    13. View of disassembled steam engine showing cylinder, piston rod, parallel motion links and steam chest. - Hacienda Azucarera La Esperanza, Steam Engine & Mill, 2.65 Mi. N of PR Rt. 2 Bridge over Manati River, Manati, Manati Municipio, PR

  2. 17. View of disassembled reduction gear parts including bull and ...

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

    17. View of disassembled reduction gear parts including bull and intermediate gears and pedestal bearing. - Hacienda Azucarera La Esperanza, Steam Engine & Mill, 2.65 Mi. N of PR Rt. 2 Bridge over Manati River, Manati, Manati Municipio, PR

  3. Systems impacts of spent fuel disassembly alternatives

    SciTech Connect

    Not Available

    1984-07-01

    Three studies were completed to evaluate four alternatives to the disposal of intact spent fuel assemblies in a geologic repository. A preferred spent fuel waste form for disposal was recommended on consideration of (1) package design and fuel/package interaction, (2) long-term, in-repository performance of the waste form, and (3) overall process performance and costs for packaging, handling, and emplacement. The four basic alternative waste forms considered were (1) end fitting removal, (2) fission gas venting, (3) disassembly and close packing, and (4) shearing/immobilization. None of the findings ruled out any alternative on the basis of waste package considerations or long-term performance of the waste form. The third alternative offers flexibility in loading that may prove attractive in the various geologic media under consideration, greatly reduces the number of packages, and has the lowest unit cost. These studies were completed in October, 1981. Since then Westinghouse Electric Corporation and the Office of Nuclear Waste Isolation have completed studies in related fields. This report is now being published to provide publicly the background material that is contained within. 47 references, 28 figures, 31 tables.

  4. Coupled anion and cation ordering in Sr{sub 3}RFe{sub 4}O{sub 10.5} (R=Y, Ho, Dy) anion-deficientperovskites

    SciTech Connect

    Abakumov, Artem M.; D'Hondt, Hans; Rossell, Marta D.; Tsirlin, Alexander A.; Gutnikova, Olga; Filimonov, Dmitry S.; Schnelle, Walter; Rosner, Helge; Hadermann, Joke; Van Tendeloo, Gustaaf; Antipov, Evgeny V.

    2010-12-15

    The Sr{sub 3}RFe{sub 4}O{sub 10.5} (R=Y, Ho, Dy) anion-deficient perovskites were prepared using a solid-state reaction in evacuated sealed silica tubes. Transmission electron microscopy and {sup 57}Fe Moessbauer spectroscopy evidenced a complete A-cations and oxygen vacancies ordering. The structure model was further refined by ab initio structure relaxation, based on density functional theory calculations. The compounds crystallize in a tetragonal a{approx}2{radical}2a{sub p{approx}}11.3 A, c{approx}4c{sub p{approx}}16 A unit cell (a{sub p}: parameter of the perovskite subcell) with the P4{sub 2}/mnm space group. Oxygen vacancies reside in the (FeO{sub 5/4{open_square}3/4}) layers, comprising corner-sharing FeO{sub 4} tetrahedra and FeO{sub 5} tetragonal pyramids, which are sandwiched between the layers of the FeO{sub 6} octahedra. Smaller R atoms occupy the 9-fold coordinated position, whereas the 10-fold coordinated positions are occupied by larger Sr atoms. The Fe sublattice is ordered aniferromagnetically up to at least 500 K, while the rare-earth sublattice remains disordered down to 2 K. -- Graphical abstract: The Sr{sub 3}RFe{sub 4}O{sub 10.5} (R=Y, Ho, Dy) anion-deficient perovskites with a complete ordering of the A-cations and oxygen vacancies have been prepared using a solid-state reaction in evacuated sealed silica tubes. Oxygen vacancies reside in the (FeO{sub 5/43/4}) layers, comprising corner-sharing FeO{sub 4} tetrahedra and FeO{sub 5} tetragonal pyramids, which are sandwiched between the layers of the FeO{sub 6} octahedra. Smaller R atoms occupy the 9-fold coordinated position, whereas the 10-fold coordinated positions are occupied by larger Sr atoms.

  5. Directed disassembly of an interfacial rubisco protein network.

    PubMed

    Onaizi, Sagheer A; Malcolm, Andrew S; He, Lizhong; Middelberg, Anton P J

    2007-05-22

    We present the first study of the directed disassembly of a protein network at the air-water interface by the synergistic action of a surfactant and an enzyme. We seek to understand the fundamentals of protein network disassembly by using rubisco adsorbed at the air-water interface as a model. We propose that rubisco adsorption at the air-water interface results in the formation of a fishnet-like network of interconnected protein molecules, capable of transmitting lateral force. The mechanical properties of the rubisco network during assembly and disassembly at the air-water interface were characterized by direct measurement of laterally transmitted force through the protein network using the Cambridge interfacial tensiometer. We have shown that, when used individually, either 2 ppm of the surfactant, sodium dodecyl benzyl sulfonate (SDOBS), or 2 ppm of the enzyme, subtilisin A (SA), were insufficient to completely disassemble the rubisco network within 1 h of treatment. However, a combination of 2 ppm SDOBS and 2 ppm SA led to almost complete disassembly within 1 h. Increasing the concentration of SA in the mixture from 2 to 10 ppm, while keeping the SDOBS concentration constant, significantly decreased the time required to completely disassemble the rubisco network. Furthermore, the initial rate of network disassembly using formulations containing SDOBS was surprisingly insensitive to this increase in SA concentration. This study gives insight into the role of lateral interactions between protein molecules at interfaces in stabilizing interfacial protein networks and shows that surfactant and enzyme working in combination proves more effective at disrupting and mobilizing the interfacial protein network than the action of either agent alone.

  6. Anaphase A: Disassembling Microtubules Move Chromosomes toward Spindle Poles

    PubMed Central

    Asbury, Charles L.

    2017-01-01

    The separation of sister chromatids during anaphase is the culmination of mitosis and one of the most strikingly beautiful examples of cellular movement. It consists of two distinct processes: Anaphase A, the movement of chromosomes toward spindle poles via shortening of the connecting fibers, and anaphase B, separation of the two poles from one another via spindle elongation. I focus here on anaphase A chromosome-to-pole movement. The chapter begins by summarizing classical observations of chromosome movements, which support the current understanding of anaphase mechanisms. Live cell fluorescence microscopy studies showed that poleward chromosome movement is associated with disassembly of the kinetochore-attached microtubule fibers that link chromosomes to poles. Microtubule-marking techniques established that kinetochore-fiber disassembly often occurs through loss of tubulin subunits from the kinetochore-attached plus ends. In addition, kinetochore-fiber disassembly in many cells occurs partly through ‘flux’, where the microtubules flow continuously toward the poles and tubulin subunits are lost from minus ends. Molecular mechanistic models for how load-bearing attachments are maintained to disassembling microtubule ends, and how the forces are generated to drive these disassembly-coupled movements, are discussed. PMID:28218660

  7. A symbolic methodology to improve disassembly process design.

    PubMed

    Rios, Pedro; Blyler, Leslie; Tieman, Lisa; Stuart, Julie Ann; Grant, Ed

    2003-12-01

    Millions of end-of-life electronic components are retired annually due to the proliferation of new models and their rapid obsolescence. The recovery of resources such as plastics from these goods requires their disassembly. The time required for each disassembly and its associated cost is defined by the operator's familiarity with the product design and its complexity. Since model proliferation serves to complicate an operator's learning curve, it is worthwhile to investigate the benefits to be gained in a disassembly operator's preplanning process. Effective disassembly process design demands the application of green engineering principles, such as those developed by Anastas and Zimmerman (Environ. Sci. Technol. 2003, 37, 94A-101A), which include regard for product complexity, structural commonality, separation energy, material value, and waste prevention. This paper introduces the concept of design symbolsto help the operator more efficiently survey product complexity with respect to location and number of fasteners to remove a structure that is common to all electronics: the housing. With a sample of 71 different computers, printers, and monitors, we demonstrate that appropriate symbols reduce the total disassembly planning time by 13.2 min. Such an improvement could well make efficient the separation of plastic that would otherwise be destined for waste-to-energy or landfill. The symbolic methodology presented may also improve Design for Recycling and Design for Maintenance and Support.

  8. Disassembling "evapotranspiration" in-situ with a complex measurement tool

    NASA Astrophysics Data System (ADS)

    Chormanski, Jaroslaw; Kleniewska, Malgorzata; Berezowski, Tomasz; Sporak-Wasilewska, Sylwia; Okruszko, Tomasz; Szatylowicz, Jan; Batelaan, Okke

    2014-05-01

    In this work we present a complex tool for measuring water fluxes in wetland ecosystems. The tool was designed to quantify processes related to interception storage on plants leafs. The measurements are conducted by combining readings from various instruments, including: eddy covariance tower (EC), field spectrometer, SapFlow system, rain gauges above and under canopy, soil moisture probes and other. The idea of this set-up is to provide continuous measurement of overall water flux from the ecosystem (EC tower), intercepted water volume and timing (field spectrometers), through-fall (rain gauges above and under canopy), transpiration (SapFlow), evaporation and soil moisture (soil moisture probes). Disassembling the water flux to the above components allows giving more insight to the interception related processes and differentiates them from the total evapotranspiration. The measurements are conducted in the Upper Biebrza Basin (NE Poland). The study area is part of the valley and is covered by peat soils (mainly peat moss with the exception of areas near the river) and receives no inundations waters of the Biebrza. The plant community of Agrostietum-Carici caninae has a dominant share here creating an up to 0.6 km wide belt along the river. The area is covered also by Caricion lasiocarpae as well as meadows and pastures Molinio-Arrhenatheretea, Phragmitetum communis. Sedges form a hummock pattern characteristic for the sedge communities in natural river valleys with wetland vegetation. The main result of the measurement set-up will be the analyzed characteristics and dynamics of interception storage for sedge ecosystems and a developed methodology for interception monitoring by use spectral reflectance technique. This will give a new insight to processes of evapotranspiration in wetlands and its components transpiration, evaporation from interception and evaporation from soil. Moreover, other important results of this project will be the estimation of energy and

  9. Planning assembly/disassembly operations for space telerobotics

    NASA Technical Reports Server (NTRS)

    Sanderson, Arthur C.; Homem De Mello, Luiz

    1987-01-01

    Space telerobotic systems will perform complex tasks of assembly, disassembly, and repair of space-based equipment. Planning such tasks requires reasoning about the functional, physical, and geometrical properties of the equipment, as well as a representation of the characteristics and capabilities of the manipulators and sensors available for the task. The And/Or graph is a useful approach to representation of feasible assembly/disassembly sequences and provides the basis for search among alternative strategies. The paper describes the use of parts entropy measures as evaluation criteria for search in the And/Or graph space. This approach leads to candidate task plans which minimize the complexity of intermediate geometrical states.

  10. Capillarity-induced disassembly of virions in carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Fan, Xiaobin; Barclay, J. Elaine; Peng, Wenchao; Li, Yang; Li, Xianyu; Zhang, Guoliang; Evans, David J.; Zhang, Fengbao

    2008-04-01

    Studying the transport and fate of viruses through nanochannels is of great importance. By using the nanochannel of a carbon nanotube (CNT) as an ideal model, we evaluated the possibility of capillarity-induced viral transport through a closely fitting nanochannel and explored the mechanisms involved. It is shown both experimentally and theoretically that Cowpea mosaic virus can enter CNTs by capillarity. However, when introduced into a nanotube the protein capsid may disassemble. During the initial capillary filling stage, anomalous needle-shaped high pressure exists in the centre of the nanotube's entrance. This high pressure, combining with the significant negative pressure within the nanotube, may account for the disassembly of the virions.

  11. CPAP promotes timely cilium disassembly to maintain neural progenitor pool.

    PubMed

    Gabriel, Elke; Wason, Arpit; Ramani, Anand; Gooi, Li Ming; Keller, Patrick; Pozniakovsky, Andrei; Poser, Ina; Noack, Florian; Telugu, Narasimha Swamy; Calegari, Federico; Šarić, Tomo; Hescheler, Jürgen; Hyman, Anthony A; Gottardo, Marco; Callaini, Giuliano; Alkuraya, Fowzan Sami; Gopalakrishnan, Jay

    2016-04-15

    A mutation in the centrosomal-P4.1-associated protein (CPAP) causes Seckel syndrome with microcephaly, which is suggested to arise from a decline in neural progenitor cells (NPCs) during development. However, mechanisms ofNPCs maintenance remain unclear. Here, we report an unexpected role for the cilium inNPCs maintenance and identifyCPAPas a negative regulator of ciliary length independent of its role in centrosome biogenesis. At the onset of cilium disassembly,CPAPprovides a scaffold for the cilium disassembly complex (CDC), which includes Nde1, Aurora A, andOFD1, recruited to the ciliary base for timely cilium disassembly. In contrast, mutatedCPAPfails to localize at the ciliary base associated with inefficientCDCrecruitment, long cilia, retarded cilium disassembly, and delayed cell cycle re-entry leading to premature differentiation of patientiPS-derivedNPCs. AberrantCDCfunction also promotes premature differentiation ofNPCs in SeckeliPS-derived organoids. Thus, our results suggest a role for cilia in microcephaly and its involvement during neurogenesis and brain size control.

  12. Assembly via disassembly: A case in machine perceptual development

    NASA Technical Reports Server (NTRS)

    Bajcsy, Ruzena K.; Tsikos, Constantine J.

    1989-01-01

    First results in the effort of learning about representations of objects is presented. The questions attempted to be answered are: What is innate and what must be derived from the environment. The problem is casted in the framework of disassembly of an object into two parts.

  13. Desmosome assembly and disassembly are membrane raft-dependent.

    PubMed

    Stahley, Sara N; Saito, Masataka; Faundez, Victor; Koval, Michael; Mattheyses, Alexa L; Kowalczyk, Andrew P

    2014-01-01

    Strong intercellular adhesion is critical for tissues that experience mechanical stress, such as the skin and heart. Desmosomes provide adhesive strength to tissues by anchoring desmosomal cadherins of neighboring cells to the intermediate filament cytoskeleton. Alterations in assembly and disassembly compromise desmosome function and may contribute to human diseases, such as the autoimmune skin blistering disease pemphigus vulgaris (PV). We previously demonstrated that PV auto-antibodies directed against the desmosomal cadherin desmoglein 3 (Dsg3) cause loss of adhesion by triggering membrane raft-mediated Dsg3 endocytosis. We hypothesized that raft membrane microdomains play a broader role in desmosome homeostasis by regulating the dynamics of desmosome assembly and disassembly. In human keratinocytes, Dsg3 is raft associated as determined by biochemical and super resolution immunofluorescence microscopy methods. Cholesterol depletion, which disrupts rafts, prevented desmosome assembly and adhesion, thus functionally linking rafts to desmosome formation. Interestingly, Dsg3 did not associate with rafts in cells lacking desmosomal proteins. Additionally, PV IgG-induced desmosome disassembly occurred by redistribution of Dsg3 into raft-containing endocytic membrane domains, resulting in cholesterol-dependent loss of adhesion. These findings demonstrate that membrane rafts are required for desmosome assembly and disassembly dynamics, suggesting therapeutic potential for raft targeting agents in desmosomal diseases such as PV.

  14. Desmosome Assembly and Disassembly Are Membrane Raft-Dependent

    PubMed Central

    Faundez, Victor; Koval, Michael; Mattheyses, Alexa L.; Kowalczyk, Andrew P.

    2014-01-01

    Strong intercellular adhesion is critical for tissues that experience mechanical stress, such as the skin and heart. Desmosomes provide adhesive strength to tissues by anchoring desmosomal cadherins of neighboring cells to the intermediate filament cytoskeleton. Alterations in assembly and disassembly compromise desmosome function and may contribute to human diseases, such as the autoimmune skin blistering disease pemphigus vulgaris (PV). We previously demonstrated that PV auto-antibodies directed against the desmosomal cadherin desmoglein 3 (Dsg3) cause loss of adhesion by triggering membrane raft-mediated Dsg3 endocytosis. We hypothesized that raft membrane microdomains play a broader role in desmosome homeostasis by regulating the dynamics of desmosome assembly and disassembly. In human keratinocytes, Dsg3 is raft associated as determined by biochemical and super resolution immunofluorescence microscopy methods. Cholesterol depletion, which disrupts rafts, prevented desmosome assembly and adhesion, thus functionally linking rafts to desmosome formation. Interestingly, Dsg3 did not associate with rafts in cells lacking desmosomal proteins. Additionally, PV IgG-induced desmosome disassembly occurred by redistribution of Dsg3 into raft-containing endocytic membrane domains, resulting in cholesterol-dependent loss of adhesion. These findings demonstrate that membrane rafts are required for desmosome assembly and disassembly dynamics, suggesting therapeutic potential for raft targeting agents in desmosomal diseases such as PV. PMID:24498201

  15. Binary Disassembly Block Coverage by Symbolic Execution vs. Recursive Descent

    DTIC Science & Technology

    2012-03-01

    19 2.2.2 Defensive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 2.2.3 Understanding... 20 2.2.4 Future-Proofing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 2.3 Issues with Disassembly and Symbolic...Execution . . . . . . . . . . . . . . 20 2.3.1 Data Type Inference . . . . . . . . . . . . . . . . . . . . . . . . . 21 2.3.1.1 Variable Recovery

  16. Teaching Assembly for Disassembly; An Under-Graduate Module Experience

    ERIC Educational Resources Information Center

    Alexandri, Eleftheria

    2014-01-01

    This paper is about the experience of teaching Assembly for Disassembly to fourth year architect students within the module of sustainable design. When designing a sustainable building one should take into consideration the fact that the building is going to be demolished in some years; thus the materials should be assembled in such a way so that…

  17. Multi-kanban mechanism for personal computer disassembly

    NASA Astrophysics Data System (ADS)

    Udomsawat, Gun; Gupta, Surendra M.; Kamarthi, Sagar V.

    2004-12-01

    The use of personal computers (PCs) continues to increase every year. According to a 1999 figure, 50 percent of all US households owned PCs, a figure that continues to rise every year. With continuous development of sophisticated software, PCs are becoming increasingly powerful. In addition, the price of a PC continues to steadily decline. Furthermore, the typical life of a PC in the workplace is approximately two to three years while in the home it is three to five years. As these PCs become obsolete, they are replaced and the old PCs are disposed of. It is estimated that between 14 and 20 million PCs are retired annually in the US. While 20 to 30% of the units may be resold, the others are discarded. These discards represent a significant potential source of lead for the waste stream. In some communities, waste cathode ray tubes (CRTs) represent the second largest source of lead in the waste stream after vehicular lead acid batteries. PCs are, therefore, not suitable for dumping in landfills. Besides, several components of a PC can be reused and then there are other valuable materials that can also be harvested. And with the advent of product stewardship, product recovery is the best solution for manufacturers. Disassembly line is perhaps the most suitable set up for disassembling PCs. However, planning and scheduling of disassembly on a disassembly line is complicated. In this paper, we discuss some of the complications including product arrival, demand arrival, inventory fluctuation and production control mechanisms. We then show how to overcome them by implementing a multi-kanban mechanism in the PC disassembly line setting. The multi-kanban mechanism relies on dynamic routing of kanbans according to the state of the system. We investigate the multi-kanban mechanism using simulation and demonstrate that this mechanism is superior to the traditional push system in terms of controlling the system"s inventory while maintaining a decent customer service level.

  18. 29 CFR 1926.1404 - Assembly/Disassembly-general requirements (applies to all assembly and disassembly operations).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction § 1926.1404 Assembly/Disassembly—general... collapse. (4) Verifying assist crane loads. When using an assist crane, the loads that will be imposed on the assist crane at each phase of assembly/disassembly must be verified in accordance with §...

  19. 29 CFR 1926.1404 - Assembly/Disassembly-general requirements (applies to all assembly and disassembly operations).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction § 1926.1404 Assembly/Disassembly—general... collapse. (4) Verifying assist crane loads. When using an assist crane, the loads that will be imposed on the assist crane at each phase of assembly/disassembly must be verified in accordance with §...

  20. 29 CFR 1926.1404 - Assembly/Disassembly-general requirements (applies to all assembly and disassembly operations).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction § 1926.1404 Assembly/Disassembly—general... collapse. (4) Verifying assist crane loads. When using an assist crane, the loads that will be imposed on the assist crane at each phase of assembly/disassembly must be verified in accordance with §...

  1. 29 CFR 1926.1404 - Assembly/Disassembly-general requirements (applies to all assembly and disassembly operations).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... REGULATIONS FOR CONSTRUCTION Cranes and Derricks in Construction § 1926.1404 Assembly/Disassembly—general... collapse. (4) Verifying assist crane loads. When using an assist crane, the loads that will be imposed on the assist crane at each phase of assembly/disassembly must be verified in accordance with §...

  2. (HFR-B1 experiment reporting and capsule disassembly)

    SciTech Connect

    Myers, B.F.

    1991-02-22

    The traveler visited the Joint Research Centre (JRC), Petten, The Netherlands, the Forschungszentrum GmbH (KFA), Juelich, Germany; and the Zentralinstitut fuer Kernforschung (ZfK), Rossendorf, Germany, during the period January 28 through February 9. At JRC, the analysis of the experiment HFR-B1 was discussed; a new schedule for issuance of the final data report was established. Other discussions at JRC concerned the capabilities of Petten to conduct two reactor experiments being proposed under the US/FRG cooperative program and the initial results of a proof test of Germany fuel spheres. At KFA, the main emphasis was on the disassembly of capsules 2 and 3 of the HFR-B1 experiment and agreement on the examinations and tests to be conducted with the disassembled components. The disassembly of capsule 3 was observed. Extensive discussions were conducted on the work, both experimental and analytical, being conducted in the Institut fuer Sicherheitsforschung und Reaktor Technologie. A major portion of the experimental work is being conducted at ZfK and a visit to this laboratory, sponosored by the KFA, was made on February 6 and 7. Cooperation with the US on the experimental and analytical work in the safety area was strongly emphasized. 1 tab.

  3. Interactome disassembly during apoptosis occurs independent of caspase cleavage.

    PubMed

    Scott, Nichollas E; Rogers, Lindsay D; Prudova, Anna; Brown, Nat F; Fortelny, Nikolaus; Overall, Christopher M; Foster, Leonard J

    2017-01-12

    Protein-protein interaction networks (interactomes) define the functionality of all biological systems. In apoptosis, proteolysis by caspases is thought to initiate disassembly of protein complexes and cell death. Here we used a quantitative proteomics approach, protein correlation profiling (PCP), to explore changes in cytoplasmic and mitochondrial interactomes in response to apoptosis initiation as a function of caspase activity. We measured the response to initiation of Fas-mediated apoptosis in 17,991 interactions among 2,779 proteins, comprising the largest dynamic interactome to date. The majority of interactions were unaffected early in apoptosis, but multiple complexes containing known caspase targets were disassembled. Nonetheless, proteome-wide analysis of proteolytic processing by terminal amine isotopic labeling of substrates (TAILS) revealed little correlation between proteolytic and interactome changes. Our findings show that, in apoptosis, significant interactome alterations occur before and independently of caspase activity. Thus, apoptosis initiation includes a tight program of interactome rearrangement, leading to disassembly of relatively few, select complexes. These early interactome alterations occur independently of cleavage of these protein by caspases.

  4. On the optimal design of the disassembly and recovery processes

    SciTech Connect

    Xanthopoulos, A.; Iakovou, E.

    2009-05-15

    This paper tackles the problem of the optimal design of the recovery processes of the end-of-life (EOL) electric and electronic products, with a special focus on the disassembly issues. The objective is to recover as much ecological and economic value as possible, and to reduce the overall produced quantities of waste. In this context, a medium-range tactical problem is defined and a novel two-phased algorithm is presented for a remanufacturing-driven reverse supply chain. In the first phase, we propose a multicriteria/goal-programming analysis for the identification and the optimal selection of the most 'desirable' subassemblies and components to be disassembled for recovery, from a set of different types of EOL products. In the second phase, a multi-product, multi-period mixed-integer linear programming (MILP) model is presented, which addresses the optimization of the recovery processes, while taking into account explicitly the lead times of the disassembly and recovery processes. Moreover, a simulation-based solution approach is proposed for capturing the uncertainties in reverse logistics. The overall approach leads to an easy-to-use methodology that could support effectively middle level management decisions. Finally, the applicability of the developed methodology is illustrated by its application on a specific case study.

  5. Disassembly of the cystovirus ϕ6 envelope by montmorillonite clay.

    PubMed

    Block, Karin A; Trusiak, Adrianna; Katz, Al; Gottlieb, Paul; Alimova, Alexandra; Wei, Hui; Morales, Jorge; Rice, William J; Steiner, Jeffrey C

    2014-02-01

    Prior studies of clay-virus interactions have focused on the stability and infectivity of nonenveloped viruses, yielding contradictory results. We hypothesize that the surface charge distribution of the clay and virus envelope dictates how the components react and affect aggregation, viral stability, and infectivity. The bacteriophage Cystoviridae species φ6 used in this study is a good model for enveloped pathogens. The interaction between φ6 and montmorillonite (MMT) clay (the primary component of bentonite) is explored by transmission electron microscopy. The analyses show that MMT-φ6 mixtures undergo heteroaggregation, forming structures in which virtually all the virions are either sequestered between MMT platelet layers or attached to platelet edges. The virions swell and undergo disassembly resulting in partial or total envelope loss. Edge-attached viral envelopes distort to increase contact area with the positively charged platelet edges indicating that the virion surface is negatively charged. The nucleocapsid (NCs) remaining after envelope removal also exhibit distortion, in contrast to detergent-produced NCs which exhibit no distortion. This visually discernible disassembly is a mechanism for loss of infectivity previously unreported by studies of nonenveloped viruses. The MMT-mediated sequestration and disassembly result in reduced infectivity, suggesting that clays may reduce infectivity of enveloped pathogenic viruses in soils and sediments.

  6. On the optimal design of the disassembly and recovery processes.

    PubMed

    Xanthopoulos, A; Iakovou, E

    2009-05-01

    This paper tackles the problem of the optimal design of the recovery processes of the end-of-life (EOL) electric and electronic products, with a special focus on the disassembly issues. The objective is to recover as much ecological and economic value as possible, and to reduce the overall produced quantities of waste. In this context, a medium-range tactical problem is defined and a novel two-phased algorithm is presented for a remanufacturing-driven reverse supply chain. In the first phase, we propose a multicriteria/goal-programming analysis for the identification and the optimal selection of the most 'desirable' subassemblies and components to be disassembled for recovery, from a set of different types of EOL products. In the second phase, a multi-product, multi-period mixed-integer linear programming (MILP) model is presented, which addresses the optimization of the recovery processes, while taking into account explicitly the lead times of the disassembly and recovery processes. Moreover, a simulation-based solution approach is proposed for capturing the uncertainties in reverse logistics. The overall approach leads to an easy-to-use methodology that could support effectively middle level management decisions. Finally, the applicability of the developed methodology is illustrated by its application on a specific case study.

  7. Disassembly of the cystovirus ϕ6 envelope by montmorillonite clay

    PubMed Central

    Block, Karin A; Trusiak, Adrianna; Katz, Al; Gottlieb, Paul; Alimova, Alexandra; Wei, Hui; Morales, Jorge; Rice, William J; Steiner, Jeffrey C

    2014-01-01

    Prior studies of clay–virus interactions have focused on the stability and infectivity of nonenveloped viruses, yielding contradictory results. We hypothesize that the surface charge distribution of the clay and virus envelope dictates how the components react and affect aggregation, viral stability, and infectivity. The bacteriophage Cystoviridae species φ6 used in this study is a good model for enveloped pathogens. The interaction between φ6 and montmorillonite (MMT) clay (the primary component of bentonite) is explored by transmission electron microscopy. The analyses show that MMT–φ6 mixtures undergo heteroaggregation, forming structures in which virtually all the virions are either sequestered between MMT platelet layers or attached to platelet edges. The virions swell and undergo disassembly resulting in partial or total envelope loss. Edge-attached viral envelopes distort to increase contact area with the positively charged platelet edges indicating that the virion surface is negatively charged. The nucleocapsid (NCs) remaining after envelope removal also exhibit distortion, in contrast to detergent-produced NCs which exhibit no distortion. This visually discernible disassembly is a mechanism for loss of infectivity previously unreported by studies of nonenveloped viruses. The MMT-mediated sequestration and disassembly result in reduced infectivity, suggesting that clays may reduce infectivity of enveloped pathogenic viruses in soils and sediments. PMID:24357622

  8. The perennial organelle: assembly and disassembly of the primary cilium

    PubMed Central

    Seeley, E. Scott; Nachury, Maxence V.

    2010-01-01

    Primary cilia contain signaling receptors of diverse classes, and ciliary dysfunction results in a variety of developmental defects. Thus, primary cilia are thought to have an important role in sensing and transducing cellular signals. Although there is clear evidence demonstrating that these organelles are assembled and disassembled dynamically as cells progress through the cell cycle, the mechanisms by which the cell cycle controls the assembly and disassembly of the primary cilium remain poorly understood. In this Commentary, we review the basic cellular mechanisms that underlie the early stages of cilium assembly and discuss how the cell cycle communicates with the ciliation program. A commonly held view is that ciliation occurs exclusively in cells that have exited the cell cycle and entered quiescence or differentiation. However, this concept is at odds with the finding that, during development, many actively proliferating cells require cilia-mediated signaling pathways to instruct their developmental fate. Here, we reassess the quiescence-centric view of ciliation by reviewing historic and current literature. We discuss ample evidence that cilia are in fact present on many proliferating cells, and that a transient peak of ciliation before the G1-S transition might be tightly coupled to entry into the DNA replication phase. Finally, we touch on the relationship between the ciliation and cell-division cycles and the tissue distribution of primary cilia in order to highlight potential roles for the primary cilium in restraining cells from the hyperproliferative state that contributes to cancer. PMID:20144999

  9. Single-molecule studies of actin assembly and disassembly factors.

    PubMed

    Smith, Benjamin A; Gelles, Jeff; Goode, Bruce L

    2014-01-01

    The actin cytoskeleton is very dynamic and highly regulated by multiple associated proteins in vivo. Understanding how this system of proteins functions in the processes of actin network assembly and disassembly requires methods to dissect the mechanisms of activity of individual factors and of multiple factors acting in concert. The advent of single-filament and single-molecule fluorescence imaging methods has provided a powerful new approach to discovering actin-regulatory activities and obtaining direct, quantitative insights into the pathways of molecular interactions that regulate actin network architecture and dynamics. Here we describe techniques for acquisition and analysis of single-molecule data, applied to the novel challenges of studying the filament assembly and disassembly activities of actin-associated proteins in vitro. We discuss the advantages of single-molecule analysis in directly visualizing the order of molecular events, measuring the kinetic rates of filament binding and dissociation, and studying the coordination among multiple factors. The methods described here complement traditional biochemical approaches in elucidating actin-regulatory mechanisms in reconstituted filamentous networks.

  10. Peroxiredoxin 1 is involved in disassembly of flagella and cilia.

    PubMed

    Gong, Fanghua; Liu, Hongtao; Li, Jie; Xue, Lexun; Zhang, Mingzhi

    2014-02-14

    Cilia/flagella are evolutionarily conserved cellular organelles. In this study, we demonstrated that Dunaliella salina Peroxiredoxin 1 (DsPrdx1) localized to the flagella and basal bodies, and was involved in flagellar disassembly. The link between DsPrdx1 and flagella of Dunaliella salina (D. salina) encouraged us to explore the function of its human homologue, Homo sapiens Peroxiredoxin 1 (HsPrdx1) in development and physiology. Our results showed that HsPrdx1 was overexpressed, and cilia were lost in esophageal squamous cell carcinoma (ESCC) cells compared with the non-cancerous esophageal epithelial cells Het-1A. Furthermore, when HsPrdx1 was knocked down by short hairpin RNA (shRNA) lentivirus in ESCC cells, the phenotype of cilia lost can be reversed, and the expression levels of tumor suppressor genes LKB1 and p-AMPK were increased, and the activity of the oncogene Aurora A was inhibited compared with those in cells transfected with scrambe-shRNA lentivirus. These findings firstly showed that Prdx1 is involved in disassembly of flagella and cilia, and suggested that the abnormal expression of the cilia-related gene including Prdx1 may affect both ciliogenesis and cancernogenesis.

  11. Cofilin cooperates with fascin to disassemble filopodial actin filaments

    PubMed Central

    Breitsprecher, Dennis; Koestler, Stefan A.; Chizhov, Igor; Nemethova, Maria; Mueller, Jan; Goode, Bruce L.; Small, J. Victor; Rottner, Klemens; Faix, Jan

    2011-01-01

    Cells use a large repertoire of proteins to remodel the actin cytoskeleton. Depending on the proteins involved, F-actin is organized in specialized protrusions such as lamellipodia or filopodia, which serve diverse functions in cell migration and sensing. Although factors responsible for directed filament assembly in filopodia have been extensively characterized, the mechanisms of filament disassembly in these structures are mostly unknown. We investigated how the actin-depolymerizing factor cofilin-1 affects the dynamics of fascincrosslinked actin filaments in vitro and in live cells. By multicolor total internal reflection fluorescence microscopy and fluorimetric assays, we found that cofilin-mediated severing is enhanced in fascin-crosslinked bundles compared with isolated filaments, and that fascin and cofilin act synergistically in filament severing. Immunolabeling experiments demonstrated for the first time that besides its known localization in lamellipodia and membrane ruffles, endogenous cofilin can also accumulate in the tips and shafts of filopodia. Live-cell imaging of fluorescently tagged proteins revealed that cofilin is specifically targeted to filopodia upon stalling of protrusion and during their retraction. Subsequent electron tomography established filopodial actin filament and/or bundle fragmentation to precisely correlate with cofilin accumulation. These results identify a new mechanism of filopodium disassembly involving both fascin and cofilin. PMID:21940796

  12. Distinct stages in stress granule assembly and disassembly

    PubMed Central

    Wheeler, Joshua R; Matheny, Tyler; Jain, Saumya; Abrisch, Robert; Parker, Roy

    2016-01-01

    Stress granules are non-membrane bound RNA-protein (RNP) assemblies that form when translation initiation is limited and contain a biphasic structure with stable core structures surrounded by a less concentrated shell. The order of assembly and disassembly of these two structures remains unknown. Time course analysis of granule assembly suggests that core formation is an early event in granule assembly. Stress granule disassembly is also a stepwise process with shell dissipation followed by core clearance. Perturbations that alter liquid-liquid phase separations (LLPS) driven by intrinsically disordered protein regions (IDR) of RNA binding proteins in vitro have the opposite effect on stress granule assembly in vivo. Taken together, these observations argue that stress granules assemble through a multistep process initiated by stable assembly of untranslated mRNPs into core structures, which could provide sufficient high local concentrations to allow for a localized LLPS driven by IDRs on RNA binding proteins. DOI: http://dx.doi.org/10.7554/eLife.18413.001 PMID:27602576

  13. Low power, biologically benign NIR light triggers polymer disassembly

    PubMed Central

    Fomina, Nadezda; McFearin, Cathryn L.; Sermsakdi, Marleen; Morachis, José M.; Almutairi, Adah

    2011-01-01

    Near infrared (NIR) irradiation can penetrate up to 10 cm deep into tissues and be remotely applied with high spatial and temporal precision. Despite its potential for various medical and biological applications, there is a dearth of biomaterials that are responsive at this wavelength region. Herein we report a polymeric material that is able to disassemble in response to biologically benign levels of NIR irradiation upon two-photon absorption. The design relies on the photolysis of the multiple pendant 4-bromo7-hydroxycoumarin protecting groups to trigger a cascade of cyclization and rearrangement reactions leading to the degradation of the polymer backbone. The new material undergoes a 50% Mw loss after 25 sec of ultraviolet (UV) irradiation by single photon absorption and 21 min of NIR irradiation via two-photon absorption. Most importantly, even NIR irradiation at biologically benign laser power is sufficient to cause significant polymer disassembly. Furthermore, this material is well tolerated by cells both before and after degradation. These results demonstrate for the first time a NIR sensitive material with potential to be used for in vivo applications. PMID:22096258

  14. Gene Expression Profiling of Flagellar Disassembly in Chlamydomonas reinhardtii

    PubMed Central

    Chamberlain, Kara L.; Miller, Steven H.; Keller, Laura R.

    2008-01-01

    Flagella are sensory organelles that interact with the environment through signal transduction and gene expression networks. We used microarray profiling to examine gene regulation associated with flagellar length change in the green alga Chlamydomonas reinhardtii. Microarrays were probed with fluorescently labeled cDNAs synthesized from RNA extracted from cells before and during flagellar assembly or disassembly. Evaluation of the gene expression profiles identified >100 clones showing at least a twofold change in expression during flagellar length changes. Products of these genes are associated not only with flagellar structure and motility but also with other cellular responses, including signal transduction and metabolism. Expression of specific genes from each category was further characterized at higher resolution by using quantitative real-time PCR (qRT–PCR). Analysis and comparison of the gene expression profiles coupled to flagellar assembly and disassembly revealed that each process involves a new and uncharacterized whole-cell response to flagellar length changes. This analysis lays the groundwork for a more comprehensive understanding of the cellular and molecular networks regulating flagellar length changes. PMID:18493036

  15. Coordination of substrate binding and ATP hydrolysis in Vps4-mediated ESCRT-III disassembly.

    PubMed

    Davies, Brian A; Azmi, Ishara F; Payne, Johanna; Shestakova, Anna; Horazdovsky, Bruce F; Babst, Markus; Katzmann, David J

    2010-10-01

    ESCRT-III undergoes dynamic assembly and disassembly to facilitate membrane exvagination processes including multivesicular body (MVB) formation, enveloped virus budding, and membrane abscission during cytokinesis. The AAA-ATPase Vps4 is required for ESCRT-III disassembly, however the coordination of Vps4 ATP hydrolysis with ESCRT-III binding and disassembly is not understood. Vps4 ATP hydrolysis has been proposed to execute ESCRT-III disassembly as either a stable oligomer or an unstable oligomer whose dissociation drives ESCRT-III disassembly. An in vitro ESCRT-III disassembly assay was developed to analyze Vps4 function during this process. The studies presented here support a model in which Vps4 acts as a stable oligomer during ATP hydrolysis and ESCRT-III disassembly. Moreover, Vps4 oligomer binding to ESCRT-III induces coordination of ATP hydrolysis at the level of individual Vps4 subunits. These results suggest that Vps4 functions as a stable oligomer that acts upon individual ESCRT-III subunits to facilitate ESCRT-III disassembly.

  16. Actin-filament disassembly: it takes two to shrink them fast.

    PubMed

    Winterhoff, Moritz; Faix, Jan

    2015-06-01

    Actin-filament disassembly is indispensable for replenishing the pool of polymerizable actin and allows continuous dynamic remodelling of the actin cytoskeleton. A new study now reveals that ADF/cofilin preferentially dismantles branched networks and provides new insights into the collaborative work of ADF/cofilin and Aip1 on filament disassembly at the molecular level.

  17. Nucleocytoplasmic transport in the midzone membrane domain controls yeast mitotic spindle disassembly

    PubMed Central

    Lucena, Rafael; Dephoure, Noah; Gygi, Steve P.; Kellogg, Douglas R.; Tallada, Victor A.

    2015-01-01

    During each cell cycle, the mitotic spindle is efficiently assembled to achieve chromosome segregation and then rapidly disassembled as cells enter cytokinesis. Although much has been learned about assembly, how spindles disassemble at the end of mitosis remains unclear. Here we demonstrate that nucleocytoplasmic transport at the membrane domain surrounding the mitotic spindle midzone, here named the midzone membrane domain (MMD), is essential for spindle disassembly in Schizosaccharomyces pombe cells. We show that, during anaphase B, Imp1-mediated transport of the AAA-ATPase Cdc48 protein at the MMD allows this disassembly factor to localize at the spindle midzone, thereby promoting spindle midzone dissolution. Our findings illustrate how a separate membrane compartment supports spindle disassembly in the closed mitosis of fission yeast. PMID:25963819

  18. Disassembling and reintegration of large telescope primary mirror

    NASA Astrophysics Data System (ADS)

    Xu, Qi-rui; Fan, Bin; Zhang, Ming

    2014-09-01

    The success of the large telescope is largely linked to the excellent performance and reliability of the primary mirror. In order to maintain the quality of its reflective surface at the high expectations of astronomers, the primary mirror after almost two or three years of astronomical observations, needs to be removed and reinstalled for its cleaning and re-coating operation. There are a series of procedures such as the primary mirror cell dissembling from telescope, mirror handling, transportation, reintegration, alignment and so on. This paper will describe the experiences of disassembling and reintegration of large telescope primary mirror, taking a two meter grade primary mirror for example. As with all advanced and complex opto-mechanical systems, there has been the usual problems and trouble shooting.

  19. Dynamic Alterations to α-Actinin Accompanying Sarcomere Disassembly and Reassembly during Cardiomyocyte Mitosis.

    PubMed

    Fan, Xiaohu; Hughes, Bryan G; Ali, Mohammad A M; Cho, Woo Jung; Lopez, Waleska; Schulz, Richard

    2015-01-01

    Although mammals are thought to lose their capacity to regenerate heart muscle shortly after birth, embryonic and neonatal cardiomyocytes in mammals are hyperplastic. During proliferation these cells need to selectively disassemble their myofibrils for successful cytokinesis. The mechanism of sarcomere disassembly is, however, not understood. To study this, we performed a series of immunofluorescence studies of multiple sarcomeric proteins in proliferating neonatal rat ventricular myocytes and correlated these observations with biochemical changes at different cell cycle stages. During myocyte mitosis, α-actinin and titin were disassembled as early as prometaphase. α-actinin (representing the sarcomeric Z-disk) disassembly precedes that of titin (M-line), suggesting that titin disassembly occurs secondary to the collapse of the Z-disk. Sarcomere disassembly was concurrent with the dissolution of the nuclear envelope. Inhibitors of several intracellular proteases could not block the disassembly of α-actinin or titin. There was a dramatic increase in both cytosolic (soluble) and sarcomeric α-actinin during mitosis, and cytosolic α-actinin exhibited decreased phosphorylation compared to sarcomeric α-actinin. Inhibition of cyclin-dependent kinase 1 (CDK1) induced the quick reassembly of the sarcomere. Sarcomere dis- and re-assembly in cardiomyocyte mitosis is CDK1-dependent and features dynamic differential post-translational modifications of sarcomeric and cytosolic α-actinin.

  20. Clathrin mediates integrin endocytosis for focal adhesion disassembly in migrating cells.

    PubMed

    Ezratty, Ellen J; Bertaux, Claire; Marcantonio, Eugene E; Gundersen, Gregg G

    2009-11-30

    Focal adhesion disassembly is regulated by microtubules (MTs) through an unknown mechanism that involves dynamin. To test whether endocytosis may be involved, we interfered with the function of clathrin or its adaptors autosomal recessive hypercholesteremia (ARH) and Dab2 (Disabled-2) and found that both treatments prevented MT-induced focal adhesion disassembly. Surface labeling experiments showed that integrin was endocytosed in an extracellular matrix-, clathrin-, and ARH- and Dab2-dependent manner before entering Rab5 endosomes. Clathrin colocalized with a subset of focal adhesions in an ARH- and Dab2-dependent fashion. Direct imaging showed that clathrin rapidly accumulated on focal adhesions during MT-stimulated disassembly and departed from focal adhesions with integrin upon their disassembly. In migrating cells, depletion of clathrin or Dab2 and ARH inhibited focal adhesion disassembly and decreased the rate of migration. These results show that focal adhesion disassembly occurs through a targeted mechanism involving MTs, clathrin, and specific clathrin adaptors and that direct endocytosis of integrins from focal adhesions mediates their disassembly in migrating cells.

  1. Intelligent decision making in disassembly process based on fuzzy reasoning petri nets.

    PubMed

    Gao, Meimei; Zhou, MengChu; Tang, Ying

    2004-10-01

    Practical disassembly process planning is extremely important for efficient material recycling and components reuse. The research work for the process planning in literature focuses on the generation of optimal sequences based on the predictive information of products. The used products, unfortunately, exhibit high uncertainty since products may experience very different conditions during their use stage. The indeterminate characteristics associated to used products often makes the predetermined plan unrealistic. Their disassembly process has to be decided dynamically adaptive to the products' specific status. To be able to deal with uncertainty in a dynamic decision making process, this paper presents a fuzzy reasoning Petri net (FRPN) model to represent related decision making rules in disassembly process. Using the proposed fuzzy reasoning algorithm based on the FRPN model, the multicriterion disassembly rules can be considered in the parallel way to make the decision automatically and quickly. Instead of producing the disassembly sequences before disassembling a whole product, the proposed method makes intelligent decisions based on dynamically updated status of components in the product at each disassembly step. Therefore, it is adaptive to the changes that arise during the process. Finally, an example is used to illustrate the application of the proposed methodology.

  2. Development of remote disassembly technology for liquid-metal reactor (LMR) fuel

    SciTech Connect

    Bradley, E.C.; Evans, J.H.; Metz, C.F. III; Weil, B.S.

    1990-01-01

    A major objective of the Consolidated Fuel Reprocessing Program (CFRP) is to develop equipment and demonstrate technology to reprocess fast breeder reactor fuel. Experimental work on fuel disassembly cutting methods began in the 1970s. High-power laser cutting was selected as the preferred cutting method for fuel disassembly. Remotely operated development equipment was designed, fabricated, installed, and tested at Oak Ridge National Laboratory (ORNL). Development testing included remote automatic operation, remote maintenance testing, and laser cutting process development. This paper summarizes the development work performed at ORNL on remote fuel disassembly. 2 refs., 1 fig.

  3. Disassembly of micelles to impart donor and acceptor gradation to enhance organic solar cell efficiency.

    PubMed

    Arulkashmir, Arulraj; Krishnamoorthy, Kothandam

    2016-02-28

    A transparent, conducting and low surface energy surface was prepared by disassembly of anionic micelles, which altered the orientation of the donor polymer and imparted gradation between the donor and acceptor. This configuration increased the solar cell device efficiency.

  4. A thermodynamic model of microtubule assembly and disassembly.

    PubMed

    Piette, Bernard M A G; Liu, Junli; Peeters, Kasper; Smertenko, Andrei; Hawkins, Timothy; Deeks, Michael; Quinlan, Roy; Zakrzewski, Wojciech J; Hussey, Patrick J

    2009-08-11

    Microtubules are self-assembling polymers whose dynamics are essential for the normal function of cellular processes including chromosome separation and cytokinesis. Therefore understanding what factors effect microtubule growth is fundamental to our understanding of the control of microtubule based processes. An important factor that determines the status of a microtubule, whether it is growing or shrinking, is the length of the GTP tubulin microtubule cap. Here, we derive a Monte Carlo model of the assembly and disassembly of microtubules. We use thermodynamic laws to reduce the number of parameters of our model and, in particular, we take into account the contribution of water to the entropy of the system. We fit all parameters of the model from published experimental data using the GTP tubulin dimer attachment rate and the lateral and longitudinal binding energies of GTP and GDP tubulin dimers at both ends. Also we calculate and incorporate the GTP hydrolysis rate. We have applied our model and can mimic published experimental data, which formerly suggested a single layer GTP tubulin dimer microtubule cap, to show that these data demonstrate that the GTP cap can fluctuate and can be several microns long.

  5. Force Generation by Microtubule Assembly/Disassembly in Mitosis and Related Movements

    PubMed Central

    Inoué, Shinya; Salmon, Edward D.

    1995-01-01

    In this article, we review the dynamic nature of the filaments (microtubules) that make up the labile fibers of the mitotic spindle and asters, we discuss the roles that assembly and disassembly of microtubules play in mitosis, and we consider how such assembling and disassembling polymer filaments can generate forces that are utilized by the living cell in mitosis and related movements. Images PMID:8590794

  6. Nek2 activation of Kif24 ensures cilium disassembly during the cell cycle

    PubMed Central

    Kim, Sehyun; Lee, Kwanwoo; Choi, Jung-Hwan; Ringstad, Niels; Dynlacht, Brian David

    2015-01-01

    Many proteins are known to promote ciliogenesis, but mechanisms that promote primary cilia disassembly before mitosis are largely unknown. Here we identify a mechanism that favours cilium disassembly and maintains the disassembled state. We show that co-localization of the S/G2 phase kinase, Nek2 and Kif24 triggers Kif24 phosphorylation, inhibiting cilia formation. We show that Kif24, a microtubule depolymerizing kinesin, is phosphorylated by Nek2, which stimulates its activity and prevents the outgrowth of cilia in proliferating cells, independent of Aurora A and HDAC6. Our data also suggest that cilium assembly and disassembly are in dynamic equilibrium, but Nek2 and Kif24 can shift the balance toward disassembly. Further, Nek2 and Kif24 are overexpressed in breast cancer cells, and ablation of these proteins restores ciliation in these cells, thereby reducing proliferation. Thus, Kif24 is a physiological substrate of Nek2, which regulates cilia disassembly through a concerted mechanism involving Kif24-mediated microtubule depolymerization. PMID:26290419

  7. Choreography of importin-α/CAS complex assembly and disassembly at nuclear pores.

    PubMed

    Sun, Changxia; Fu, Guo; Ciziene, Danguole; Stewart, Murray; Musser, Siegfried M

    2013-04-23

    Nuclear pore complexes (NPCs) mediate the exchange of macromolecules between the cytoplasm and the nucleoplasm. Soluble nuclear transport receptors bind signal-dependent cargos to form transport complexes that diffuse through the NPC and are then disassembled. Although transport receptors enable the NPC's permeability barrier to be overcome, directionality is established by complex assembly and disassembly. Here, we delineate the choreography of importin-α/CAS complex assembly and disassembly in permeabilized cells, using single-molecule fluorescence resonance energy transfer and particle tracking. Monitoring interaction sequences in intact NPCs ensures spatiotemporal preservation of structures and interactions critical for activity in vivo. We show that key interactions between components are reversible, multiple outcomes are often possible, and the assembly and disassembly of complexes are precisely controlled to occur at the appropriate place and time. Importin-α mutants that impair interactions during nuclear import were used together with cytoplasmic Ran GTPase-activating factors to demonstrate that importin-α/CAS complexes form in the nuclear basket region, at the termination of protein import, and disassembly of importin-α/CAS complexes after export occurs in the cytoplasmic filament region of the NPC. Mathematical models derived from our data emphasize the intimate connection between transport and the coordinated assembly and disassembly of importin-α/CAS complexes for generating productive transport cycles.

  8. Vps4 disassembles an ESCRT-III filament by global unfolding and processive translocation

    PubMed Central

    Yang, Bei; Stjepanovic, Goran; Shen, Qingtao; Martin, Andreas; Hurley, James H.

    2015-01-01

    The AAA+ ATPase Vps4 disassembles ESCRT-III and is essential for HIV-1 budding and other pathways. Vps4 is a paradigmatic member of a class of hexameric AAA+ ATPases that disassemble protein complexes without degradation. To distinguish between local displacement versus global unfolding mechanisms for complex disassembly, we carried out hydrogen-deuterium exchange during Saccharomyces cerevisiae Vps4 disassembly of of a chimeric Vps24-2 ESCRT-III filament. EX1 exchange behavior shows that Vps4 completely unfolds ESCRT-III substrates on a time scale consistent with the disassembly reaction. The established unfoldase ClpX showed the same pattern, demonstrating a common unfolding mechanism. Vps4 hexamers containing a single cysteine residue in the pore loops were cross-linked to ESCRT-III subunits containing unique cysteine within the folded core domain. These data support a mechanism in which Vps4 disassembles its substrates by completely unfolding them and threading them through the central pore. PMID:25938660

  9. The effect of sudden server breakdown on the performance of a disassembly line

    NASA Astrophysics Data System (ADS)

    Udomsawat, Gun; Gupta, Surendra M.

    2005-11-01

    Product and material recovery relies on the disassembly process to separate target components or materials from the end-of-life (EOL) products. Disassembly line is especially effective when products in large quantity are disassembled. Unlike an assembly line, a disassembly line is more complex and is subjected to numerous uncertainties including stochastic and multi-level arrivals of component demands, stochastic arrival times for EOL products, and process interruption due to equipment failure. These factors seriously impair the control mechanism in the disassembly line. A common production control mechanism is the traditional push system (TPS). TPS responds to the aforementioned complications by carrying substantial amounts of inventories. An alternative control mechanism is a newly developed multi-kanban pull system (MKS) that relies on dynamic routing of kanbans, which tends to minimize the system's inventories while maintaining demand serviceability. In this paper we explore the impact of sudden breakdown of server on the performance of a disassembly line. We compare the overall performances of the TPS and MKS by considering two scenarios. We present the solution procedure and results for these cases.

  10. Mucus barrier-triggered disassembly of siRNA nanocarriers

    NASA Astrophysics Data System (ADS)

    Thomsen, Troels B.; Li, Leon; Howard, Kenneth A.

    2014-10-01

    The mucus overlying mucosal epithelial surfaces presents not only a biological barrier to the penetration of potential pathogens, but also therapeutic modalities including RNAi-based nanocarriers. Movement of nanomedicines across the mucus barriers of the gastrointestinal mucosa is modulated by interactions of the nanomedicine carriers with mucin glycoproteins inside the mucus, potentiated by the large surface area of the nanocarrier. We have developed a fluorescence activation-based reporter system showing that the interaction between polyanionic mucins and the cationic chitosan/small interfering RNA (siRNA) nanocarriers (polyplexes) results in the disassembly and consequent triggered release of fluorescent siRNA. The quantity of release was found to be dependent on the molar ratio between chitosan amino groups and siRNA phosphate groups (NP ratio) of the polyplexes with a maximal estimated 48.6% release of siRNA over 30 min at NP 60. Furthermore, a microfluidic in vitro model of the gastrointestinal mucus barrier was used to visualize the dynamic interaction between chitosan/siRNA nanocarriers and native purified porcine stomach mucins. We observed strong interactions and aggregations at the mucin-liquid interface, followed by an NP ratio dependent release and consequent diffusion of siRNA across the mucin barrier. This work describes a new model of interaction at the nanocarrier-mucin interface and has important implications for the design and development of nucleic acid-based nanocarrier therapeutics for mucosal disease treatments and also provides insights into nanoscale pathogenic processes.The mucus overlying mucosal epithelial surfaces presents not only a biological barrier to the penetration of potential pathogens, but also therapeutic modalities including RNAi-based nanocarriers. Movement of nanomedicines across the mucus barriers of the gastrointestinal mucosa is modulated by interactions of the nanomedicine carriers with mucin glycoproteins inside the

  11. Actin disassembly by cofilin, coronin, and Aip1 occurs in bursts and is inhibited by barbed-end cappers

    PubMed Central

    Kueh, Hao Yuan; Charras, Guillaume T.; Mitchison, Timothy J.; Brieher, William M.

    2008-01-01

    Turnover of actin filaments in cells requires rapid actin disassembly in a cytoplasmic environment that thermodynamically favors assembly because of high concentrations of polymerizable monomers. We here image the disassembly of single actin filaments by cofilin, coronin, and actin-interacting protein 1, a purified protein system that reconstitutes rapid, monomer-insensitive disassembly (Brieher, W.M., H.Y. Kueh, B.A. Ballif, and T.J. Mitchison. 2006. J. Cell Biol. 175:315–324). In this three-component system, filaments disassemble in abrupt bursts that initiate preferentially, but not exclusively, from both filament ends. Bursting disassembly generates unstable reaction intermediates with lowered affinity for CapZ at barbed ends. CapZ and cytochalasin D (CytoD), a barbed-end capping drug, strongly inhibit bursting disassembly. CytoD also inhibits actin disassembly in mammalian cells, whereas latrunculin B, a monomer sequestering drug, does not. We propose that bursts of disassembly arise from cooperative separation of the two filament strands near an end. The differential effects of drugs in cells argue for physiological relevance of this new disassembly pathway and potentially explain discordant results previously found with these drugs. PMID:18663144

  12. Microcalorimetric study of adsorption and disassembling of virus-like particles on anion exchange chromatography media.

    PubMed

    Yu, Mengran; Zhang, Songping; Zhang, Yan; Yang, Yanli; Ma, Guanghui; Su, Zhiguo

    2015-04-03

    Chromatographic purification of virus-like particles (VLPs) is important to the development of modern vaccines. However, disassembly of the VLPs on the solid-liquid interface during chromatography process could be a serious problem. In this study, isothermal titration calorimetric (ITC) measurements, together with chromatography experiments, were performed on the adsorption and disassembling of multi-subunits hepatitis B virus surface antigen virus-like particles (HB-VLPs). Two gigaporous ion-exchange chromatography (IEC) media, DEAE-AP-280 nm and DEAE-POROS, were used. The application of gigaporous media with high ligand density led to significantly increased irreversible disassembling of HB-VLPs and consequently low antigen activity recovery during IEC process. To elucidate the thermodynamic mechanism of the effect of ligand density on the adsorption and conformational change of VLPs, a thermodynamic model was proposed. With this model, one can obtain the intrinsic molar enthalpy changes related to the binding of VLPs and the accompanying conformational change on the liquid-solid interface during its adsorption. This model assumes that, when intact HB-VLPs interact with the IEC media, the total adsorbed proteins contain two states, the intact formation and the disassembled formation; accordingly, the apparent adsorption enthalpy, ΔappH, which can be directly measured from ITC experiments, presents the sum of three terms: (1) the intrinsic molar enthalpy change associated to the binding of intact HB-VLPs (ΔbindHintact), (2) the intrinsic molar enthalpy change associated to the binding of HB-VLPs disassembled formation (ΔbindHdis), and (3) the enthalpy change accompanying the disassembling of HB-VLPs (ΔconfHdis). The intrinsic binding of intact HB-VLPs and the disassembled HB-VLPs to both kinds of gigaporous media (each of which has three different ligand densities), were all observed to be entropically driven as indicated by positive values of

  13. Role of CCT chaperonin in the disassembly of mitotic checkpoint complexes.

    PubMed

    Kaisari, Sharon; Sitry-Shevah, Danielle; Miniowitz-Shemtov, Shirly; Teichner, Adar; Hershko, Avram

    2017-01-31

    The mitotic checkpoint system prevents premature separation of sister chromatids in mitosis and thus ensures the fidelity of chromosome segregation. When this checkpoint is active, a mitotic checkpoint complex (MCC), composed of the checkpoint proteins Mad2, BubR1, Bub3, and Cdc20, is assembled. MCC inhibits the ubiquitin ligase anaphase promoting complex/cyclosome (APC/C), whose action is necessary for anaphase initiation. When the checkpoint signal is turned off, MCC is disassembled, a process required for exit from checkpoint-arrested state. Different moieties of MCC are disassembled by different ATP-requiring processes. Previous work showed that Mad2 is released from MCC by the joint action of the TRIP13 AAA-ATPase and the Mad2-binding protein p31(comet) Now we have isolated from extracts of HeLa cells an ATP-dependent factor that releases Cdc20 from MCC and identified it as chaperonin containing TCP1 or TCP1-Ring complex (CCT/TRiC chaperonin), a complex known to function in protein folding. Bacterially expressed CCT5 chaperonin subunits, which form biologically active homooligomers [Sergeeva, et al. (2013) J Biol Chem 288(24):17734-17744], also promote the disassembly of MCC. CCT chaperonin further binds and disassembles subcomplexes of MCC that lack Mad2. Thus, the combined action of CCT chaperonin with that of TRIP13 ATPase promotes the complete disassembly of MCC, necessary for the inactivation of the mitotic checkpoint.

  14. Coordinated Action of Nap1 and RSC in Disassembly of Tandem Nucleosomes

    PubMed Central

    Prasad, Rashmi; D'Arcy, Sheena; Hada, Arjan; Luger, Karolin

    2016-01-01

    The SWI/SNF and RSC family of ATP-dependent chromatin remodelers disassembles nucleosomes by moving nucleosomes into the vicinity of adjoining nucleosomes. We found that the histone chaperone Nap1 efficiently promotes disassembly of adjacent nucleosomes with which RSC collides and not the disassembly of nucleosomes mobilized by RSC. Nap1 is specific to RSC, as it does not target SWI/SNF, its paralog in Saccharomyces cerevisiae. Extensive mutational analysis of Nap1 has revealed that Nap1 affinity for histones H2A-H2B and H3-H4 and its ability to displace histones from DNA are required for Nap1 to enhance RSC-mediated disassembly. Other histone chaperones, such as Vps75, that also bind histones are not able to enhance RSC-mediated disassembly. Our study suggests a mechanism by which Nap1 is recruited to actively transcribed regions and assists in the passage of the transcription complex through chromatin, and it provides a novel mechanism for the coordinated action of RSC and Nap1. PMID:27273866

  15. akirin is required for diakinesis bivalent structure and synaptonemal complex disassembly at meiotic prophase I.

    PubMed

    Clemons, Amy M; Brockway, Heather M; Yin, Yizhi; Kasinathan, Bhavatharini; Butterfield, Yaron S; Jones, Steven J M; Colaiácovo, Monica P; Smolikove, Sarit

    2013-04-01

    During meiosis, evolutionarily conserved mechanisms regulate chromosome remodeling, leading to the formation of a tight bivalent structure. This bivalent, a linked pair of homologous chromosomes, is essential for proper chromosome segregation in meiosis. The formation of a tight bivalent involves chromosome condensation and restructuring around the crossover. The synaptonemal complex (SC), which mediates homologous chromosome association before crossover formation, disassembles concurrently with increased condensation during bivalent remodeling. Both chromosome condensation and SC disassembly are likely critical steps in acquiring functional bivalent structure. The mechanisms controlling SC disassembly, however, remain unclear. Here we identify akir-1 as a gene involved in key events of meiotic prophase I in Caenorhabditis elegans. AKIR-1 is a protein conserved among metazoans that lacks any previously known function in meiosis. We show that akir-1 mutants exhibit severe meiotic defects in late prophase I, including improper disassembly of the SC and aberrant chromosome condensation, independently of the condensin complexes. These late-prophase defects then lead to aberrant reconfiguring of the bivalent. The meiotic divisions are delayed in akir-1 mutants and are accompanied by lagging chromosomes. Our analysis therefore provides evidence for an important role of proper SC disassembly in configuring a functional bivalent structure.

  16. The MAP kinase pathway coordinates crossover designation with disassembly of synaptonemal complex proteins during meiosis

    PubMed Central

    Nadarajan, Saravanapriah; Mohideen, Firaz; Tzur, Yonatan B; Ferrandiz, Nuria; Crawley, Oliver; Montoya, Alex; Faull, Peter; Snijders, Ambrosius P; Cutillas, Pedro R; Jambhekar, Ashwini; Blower, Michael D; Martinez-Perez, Enrique; Harper, J Wade; Colaiacovo, Monica P

    2016-01-01

    Asymmetric disassembly of the synaptonemal complex (SC) is crucial for proper meiotic chromosome segregation. However, the signaling mechanisms that directly regulate this process are poorly understood. Here we show that the mammalian Rho GEF homolog, ECT-2, functions through the conserved RAS/ERK MAP kinase signaling pathway in the C. elegans germline to regulate the disassembly of SC proteins. We find that SYP-2, a SC central region component, is a potential target for MPK-1-mediated phosphorylation and that constitutively phosphorylated SYP-2 impairs the disassembly of SC proteins from chromosomal domains referred to as the long arms of the bivalents. Inactivation of MAP kinase at late pachytene is critical for timely disassembly of the SC proteins from the long arms, and is dependent on the crossover (CO) promoting factors ZHP-3/RNF212/Zip3 and COSA-1/CNTD1. We propose that the conserved MAP kinase pathway coordinates CO designation with the disassembly of SC proteins to ensure accurate chromosome segregation. DOI: http://dx.doi.org/10.7554/eLife.12039.001 PMID:26920220

  17. Disassembly of Simian Virus 40 during Passage through the Endoplasmic Reticulum and in the Cytoplasm

    PubMed Central

    Kuksin, Dmitry

    2012-01-01

    The nonenveloped polyomavirus simian virus 40 (SV40) is taken up into cells by a caveola-mediated endocytic process that delivers the virus to the endoplasmic reticulum (ER). Within the ER lumen, the capsid undergoes partial disassembly, which exposes its internal capsid proteins VP2 and VP3 to immunostaining with antibodies. We demonstrate here that the SV40 genome does not become accessible to detection while the virus is in the ER. Instead, the genome becomes accessible two distinct detection procedures, one using anti-bromodeoxyuridine antibodies and the other using a 5-ethynyl-2-deoxyuridine-based chemical reaction, only after the emergence of partially disassembled SV40 particles in the cytoplasm. These cytoplasmic particles retain some of the SV40 capsid proteins, VP1, VP2, and VP3, in addition to the viral genome. Thus, SV40 particles undergo discrete disassembly steps during entry that are separated temporally and topologically. First, a partial disassembly of the particles occurs in the ER, which exposes internal capsid proteins VP2 and VP3. Then, in the cytoplasm, disassembly progresses further to also make the genomic DNA accessible to immune detection. PMID:22090139

  18. Disassembly of simian virus 40 during passage through the endoplasmic reticulum and in the cytoplasm.

    PubMed

    Kuksin, Dmitry; Norkin, Leonard C

    2012-02-01

    The nonenveloped polyomavirus simian virus 40 (SV40) is taken up into cells by a caveola-mediated endocytic process that delivers the virus to the endoplasmic reticulum (ER). Within the ER lumen, the capsid undergoes partial disassembly, which exposes its internal capsid proteins VP2 and VP3 to immunostaining with antibodies. We demonstrate here that the SV40 genome does not become accessible to detection while the virus is in the ER. Instead, the genome becomes accessible two distinct detection procedures, one using anti-bromodeoxyuridine antibodies and the other using a 5-ethynyl-2-deoxyuridine-based chemical reaction, only after the emergence of partially disassembled SV40 particles in the cytoplasm. These cytoplasmic particles retain some of the SV40 capsid proteins, VP1, VP2, and VP3, in addition to the viral genome. Thus, SV40 particles undergo discrete disassembly steps during entry that are separated temporally and topologically. First, a partial disassembly of the particles occurs in the ER, which exposes internal capsid proteins VP2 and VP3. Then, in the cytoplasm, disassembly progresses further to also make the genomic DNA accessible to immune detection.

  19. SWI/SNF has intrinsic nucleosome disassembly activity that is dependent on adjacent nucleosomes.

    PubMed

    Dechassa, Mekonnen Lemma; Sabri, Abdellah; Pondugula, Santhi; Kassabov, Stefan R; Chatterjee, Nilanjana; Kladde, Michael P; Bartholomew, Blaine

    2010-05-28

    The ATP-dependent chromatin remodeling complex SWI/SNF regulates transcription and has been implicated in promoter nucleosome eviction. Efficient nucleosome disassembly by SWI/SNF alone in biochemical assays, however, has not been directly observed. Employing a model system of dinucleosomes rather than mononucleosomes, we demonstrate that remodeling leads to ordered and efficient disassembly of one of the two nucleosomes. An H2A/H2B dimer is first rapidly displaced, and then, in a slower reaction, an entire histone octamer is lost. Nucleosome disassembly by SWI/SNF did not require additional factors such as chaperones or acceptors of histones. Observations in single molecules as well as bulk measurement suggest that a key intermediate in this process is one in which a nucleosome is moved toward the adjacent nucleosome. SWI/SNF recruited by the transcriptional activator Gal4-VP16 preferentially mobilizes the proximal nucleosome and destabilizes the adjacent nucleosome.

  20. A Self-produced Trigger for Biofilm Disassembly that Targets Exopolysaccharide

    PubMed Central

    Kolodkin-Gal, Ilana; Cao, Shugeng; Chai, Liraz; Böttcher, Thomas; Kolter, Roberto; Clardy, Jon; Losick, Richard

    2012-01-01

    Biofilms are structured communities of bacteria that are held together by an extracellular matrix consisting of protein and exopolysaccharide. Biofilms often have a limited lifespan, disassembling as nutrients become exhausted and waste products accumulate. D-amino acids were previously identified as a self-produced factor that mediates biofilm disassembly by causing the release of the protein component of the matrix in Bacillus subtilis. Here we report that B. subtilis produces an additional biofilm-disassembly factor, norspermidine. Dynamic light scattering and scanning electron microscopy experiments indicated that norspermidine interacts directly and specifically with exopolysaccharide. D-amino acids and norspermidine acted together to break down existing biofilms and mutants blocked in the production of both formed long-lived biofilms. Norspermidine, but not closely related polyamines, prevented biofilm formation by B. subtilis, Escherichia coli and Staphylococcus aureus. PMID:22541437

  1. Node-by-node disassembly of a mutualistic interaction web driven by species introductions

    PubMed Central

    Rodriguez-Cabal, Mariano A.; Barrios-Garcia, M. Noelia; Amico, Guillermo C.; Aizen, Marcelo A.; Sanders, Nathan J.

    2013-01-01

    Interaction webs summarize the diverse interactions among species in communities. The addition or loss of particular species and the alteration of key interactions can lead to the disassembly of the entire interaction web, although the nontrophic effects of species loss on interaction webs are poorly understood. We took advantage of ongoing invasions by a suite of exotic species to examine their impact in terms of the disassembly of an interaction web in Patagonia, Argentina. We found that the reduction of one species (a host of a keystone mistletoe species) resulted in diverse indirect effects that led to the disassembly of an interaction web through the loss of the mistletoe, two key seed-dispersers (a marsupial and a bird), and a pollinator (hummingbird). Our results demonstrate that the gains and losses of species are both consequences and drivers of global change that can lead to underappreciated cascading coextinctions through the disruption of mutualisms. PMID:24067653

  2. Assembly/Disassembly of DNA-Au Nanoparticles: A Strategy of Intervention

    DOE PAGES

    Lim, I-Im S.; Wang, Lingyan; Chandrachud, Uma; ...

    2008-01-01

    This report describes the viability of a strategy for manipulating the assembly/disassembly processes of DNA-Au nanoparticles by molecular intervention. Using the temperature-induced assembly and disassembly processes of DNAs and gold nanoparticles as a model system, the introduction of a molecular recognition probe is demonstrated to lead to the intervention of the assembly/disassembly processes depending on its specific biorecognition. This process can be detected by monitoring the change in the optical properties of gold nanoparticles and their DNA assemblies. Implications of the preliminary results to exploration of the resulting nanostructures for fine-tuning of the interfacial reactivities in DNA-based bioassays and biomaterialmore » engineering are also discussed.« less

  3. Clathrin Coat Disassembly Illuminates the Mechanisms of Hsp70 Force Generation

    PubMed Central

    Liao, Hsien-Shun; Cuéllar, Jorge; Jin, Suping; Valpuesta, Jose M.; Jin, Albert J.; Lafer, Eileen M.

    2016-01-01

    Hsp70s use ATP hydrolysis to disrupt protein:protein associations or move macromolecules. One example is Hsc70-mediated disassembly of clathrin coats that form on vesicles during endocytosis. We exploit the exceptional features of these coats to test three models—Brownian ratchet, power-stroke and entropic pulling—proposed to explain how Hsp70s transform their substrates. Our data rule out the ratchet and power-stroke models, and instead support a collision pressure mechanism whereby collisions between clathrin coat walls and Hsc70s drive coats apart. Collision pressure is the complement to the pulling force described in the entropic pulling model. We also find that self-association can augment collision pressure to allow disassembly of clathrin lattices predicted to resist disassembly. These results illuminate how Hsp70s generate the forces that transform their substrates. PMID:27478930

  4. Disassembly properties and material characterisation of household small waste electric and electronic equipment.

    PubMed

    Bovea, María D; Pérez-Belis, Victoria; Ibáñez-Forés, Valeria; Quemades-Beltrán, Pilar

    2016-07-01

    This paper is focused on characterising small waste electric and electronic equipment, specifically small household appliances, from two different points of views: disassembly properties and material identification. The sample for this characterisation was obtained from a selective collection campaign organised in Castellón de la Plana (Spain). A total amount of 833.7kg (749 units) of small waste electric and electronic equipment was collected, of which 23.3% by weight and 22.4% by units belonged to the subcategory household equipment. This subcategory, composed of appliances such as vacuum cleaners, toasters, sandwich makers, hand blenders, juicers, coffee makers, hairdryers, scales, irons and heaters, was first disassembled in order to analyse different aspects of the disassembly process for each equipment type: type of joints, ease of identification of materials, ease of access to joints for extracting components, ease of separation of components from the whole, uniformity of tools needed for the disassembly process and possibility of reassembly after disassembly. Results show that the most common joints used in these equipment types are snap-fits and screws, although some permanent joints have also been identified. Next, the material composition of each component of each appliance belonging to each equipment type was identified visually and with additional mechanical trials and testing. It can be observed that plastic and electric/electronic components are present in all the equipment types analysed and are also the material fractions that appear with higher percentages in the material composition: 41.1wt% and 39.1wt% for the plastic fraction and electric/electronic components, respectively. The most common plastics are: polypropylene (PP), acrylonitrile butadiene styrene (ABS) and polycarbonate (PC), while the most common electric/electronic components are: cable, plug and printed circuit boards. Results also show that disassembly properties and material

  5. A heuristic solution for the disassembly line balancing problem incorporating sequence dependent costs

    NASA Astrophysics Data System (ADS)

    Lambert, A. J. D.; Gupta, Surendra M.

    2005-11-01

    This paper deals with disassembly sequencing problems subjected to sequence dependent disassembly costs. We present a heuristic and an iterative method based on partial branch and bound concept to solve such problems. Since heuristic methods intrinsically generate suboptimum solutions, we compared the heuristically obtained solutions with the exact solutions to see if they are reasonably good or not. This process, however, is limited to small or perhaps medium sized problems only as the required CPU time for exact methods tends to increase exponentially with the problem size. For the problems tested, we observed that the methods described in this paper generate surprisingly good results using almost negligible amount of CPU time.

  6. Disassembly of the fusion-1 capsule after irradiation in the BOR-60 reactor

    SciTech Connect

    Tsai, H.; Kazakov, V.A.; Chakin, V.P.

    1997-04-01

    A U.S./Russia (RF) collaborative irradiation experiment, Fusion-1, was completed in June 1996 after reaching a peak exposure of {approx}17 dpa in the BOR-60 fast reactor at the Research Institute of Atomic Reactors (RIAR) in Russia. The specimens were vanadium alloys, mainly of recent heats from both countries. In this reporting period, the capsule was disassembled at the RIAR hot cells and all test specimens were successfully retrieved. For the disassembly, an innovative method of using a heated diffusion oil to melt and separate the lithium bond from the test specimens was adopted. This method proved highly successful.

  7. 29 CFR 1926.1407 - Power line safety (up to 350 kV)-assembly and disassembly.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... so that it is in view of the operator and (except for overhead gantry and tower cranes) at least two... Cranes and Derricks in Construction § 1926.1407 Power line safety (up to 350 kV)—assembly and disassembly...) Assembly/disassembly below power lines prohibited. No part of a crane/derrick, load line, or...

  8. 29 CFR 1926.1407 - Power line safety (up to 350 kV)-assembly and disassembly.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... so that it is in view of the operator and (except for overhead gantry and tower cranes) at least two... Cranes and Derricks in Construction § 1926.1407 Power line safety (up to 350 kV)—assembly and disassembly...) Assembly/disassembly below power lines prohibited. No part of a crane/derrick, load line, or...

  9. 29 CFR 1926.1407 - Power line safety (up to 350 kV)-assembly and disassembly.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... so that it is in view of the operator and (except for overhead gantry and tower cranes) at least two... Cranes and Derricks in Construction § 1926.1407 Power line safety (up to 350 kV)—assembly and disassembly...) Assembly/disassembly below power lines prohibited. No part of a crane/derrick, load line, or...

  10. 29 CFR 1926.1407 - Power line safety (up to 350 kV)-assembly and disassembly.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... so that it is in view of the operator and (except for overhead gantry and tower cranes) at least two... Cranes and Derricks in Construction § 1926.1407 Power line safety (up to 350 kV)—assembly and disassembly...) Assembly/disassembly below power lines prohibited. No part of a crane/derrick, load line, or...

  11. Disassembly Sequence Optimization for Large-Scale Products With Multiresource Constraints Using Scatter Search and Petri Nets.

    PubMed

    Guo, Xiwang; Liu, Shixin; Zhou, MengChu; Tian, Guangdong

    2016-11-01

    Disassembly modeling and planning are meaningful and important to the reuse, recovery, and recycling of obsolete and discarded products. However, the existing methods pay little or no attention to resources constraints, e.g., disassembly operators and tools. Thus a resulting plan when being executed may be ineffective in actual product disassembly. This paper proposes to model and optimize selective disassembly sequences subject to multiresource constraints to maximize disassembly profit. Moreover, two scatter search algorithms with different combination operators, namely one with precedence preserved crossover combination operator and another with path-relink combination operator, are designed to solve the proposed model. Their validity is shown by comparing them with the optimization results from well-known optimization software CPLEX for different cases. The experimental results illustrate the effectiveness of the proposed method.

  12. Mechanical disassembly of single virus particles reveals kinetic intermediates predicted by theory.

    PubMed

    Castellanos, Milagros; Pérez, Rebeca; Carrillo, Pablo J P; de Pablo, Pedro J; Mateu, Mauricio G

    2012-06-06

    New experimental approaches are required to detect the elusive transient intermediates predicted by simulations of virus assembly or disassembly. Here, an atomic force microscope (AFM) was used to mechanically induce partial disassembly of single icosahedral T=1 capsids and virions of the minute virus of mice. The kinetic intermediates formed were imaged by AFM. The results revealed that induced disassembly of single minute-virus-of-mice particles is frequently initiated by loss of one of the 20 equivalent capsomers (trimers of capsid protein subunits) leading to a stable, nearly complete particle that does not readily lose further capsomers. With lower frequency, a fairly stable, three-fourths-complete capsid lacking one pentamer of capsomers and a free, stable pentamer were obtained. The intermediates most frequently identified (capsids missing one capsomer, capsids missing one pentamer of capsomers, and free pentamers of capsomers) had been predicted in theoretical studies of reversible capsid assembly based on thermodynamic-kinetic models, molecular dynamics, or oligomerization energies. We conclude that mechanical manipulation and imaging of simple virus particles by AFM can be used to experimentally identify kinetic intermediates predicted by simulations of assembly or disassembly.

  13. Sequential depletion and acquisition of proteins during Golgi stack disassembly and reformation.

    PubMed

    Schoberer, Jennifer; Runions, John; Steinkellner, Herta; Strasser, Richard; Hawes, Chris; Osterrieder, Anne

    2010-11-01

    Herein, we report the stepwise transport of multiple plant Golgi membrane markers during disassembly of the Golgi apparatus in tobacco leaf epidermal cells in response to the induced expression of the GTP-locked Sar1p or Brefeldin A (BFA), and reassembly on BFA washout. The distribution of fluorescent Golgi-resident N-glycan processing enzymes and matrix proteins (golgins) with specific cis-trans-Golgi sub-locations was followed by confocal microscopy during disassembly and reassembly. The first event during Golgi disassembly was the loss of trans-Golgi enzymes and golgins from Golgi membranes, followed by a sequential redistribution of medial and cis-Golgi enzymes into the endoplasmic reticulum (ER), whilst golgins were relocated to the ER or cytoplasm. This event was confirmed by fractionation and immuno-blotting. The sequential redistribution of Golgi components in a trans-cis sequence may highlight a novel retrograde trafficking pathway between the trans-Golgi and the ER in plants. Release of Golgi markers from the ER upon BFA washout occurred in the opposite sequence, with cis-matrix proteins labelling Golgi-like structures before cis/medial enzymes. Trans-enzyme location was preceded by trans-matrix proteins being recruited back to Golgi membranes. Our results show that Golgi disassembly and reassembly occur in a highly ordered fashion in plants.

  14. Spastin and ESCRT-III coordinate mitotic spindle disassembly and nuclear envelope sealing.

    PubMed

    Vietri, Marina; Schink, Kay O; Campsteijn, Coen; Wegner, Catherine Sem; Schultz, Sebastian W; Christ, Liliane; Thoresen, Sigrid B; Brech, Andreas; Raiborg, Camilla; Stenmark, Harald

    2015-06-11

    At the onset of metazoan cell division the nuclear envelope breaks down to enable capture of chromosomes by the microtubule-containing spindle apparatus. During anaphase, when chromosomes have separated, the nuclear envelope is reassembled around the forming daughter nuclei. How the nuclear envelope is sealed, and how this is coordinated with spindle disassembly, is largely unknown. Here we show that endosomal sorting complex required for transport (ESCRT)-III, previously found to promote membrane constriction and sealing during receptor sorting, virus budding, cytokinesis and plasma membrane repair, is transiently recruited to the reassembling nuclear envelope during late anaphase. ESCRT-III and its regulatory AAA (ATPase associated with diverse cellular activities) ATPase VPS4 are specifically recruited by the ESCRT-III-like protein CHMP7 to sites where the reforming nuclear envelope engulfs spindle microtubules. Subsequent association of another ESCRT-III-like protein, IST1, directly recruits the AAA ATPase spastin to sever microtubules. Disrupting spastin function impairs spindle disassembly and results in extended localization of ESCRT-III at the nuclear envelope. Interference with ESCRT-III functions in anaphase is accompanied by delayed microtubule disassembly, compromised nuclear integrity and the appearance of DNA damage foci in subsequent interphase. We propose that ESCRT-III, VPS4 and spastin cooperate to coordinate nuclear envelope sealing and spindle disassembly at nuclear envelope-microtubule intersection sites during mitotic exit to ensure nuclear integrity and genome safeguarding, with a striking mechanistic parallel to cytokinetic abscission.

  15. Effect of flow on the freeze-out density and temperature of disassembling hot nuclei

    NASA Astrophysics Data System (ADS)

    Shlomo, S.; de, J. N.; Kolomiets, A.

    1997-05-01

    The method of Albergo, Costa, Costanzo, and Rubbino to determine the temperature and free nucleon density of a disassembling hot nuclear source from fragment yields is modified to include the effects of radial collective flow, generated in the system from compression. We find that the freeze-out density increased substantially whereas the extracted temperature is modified only a little.

  16. Nano-mechanical characterization of disassembling amyloid fibrils using the Peak Force QNM method.

    PubMed

    Wang, Wenpin; Guo, Zongxia; Sun, Jing; Li, Zhibo

    2017-02-01

    The comprehensive understanding of disassembly mechanism of amyloid fibrils requires nano-scale characterization of the mechanical properties of amyloid fibrils during the disassembly process. In this work, gemini surfactant C12 C6 C12 Br2 micelles were used as a probe to disassemble Aβ(1-40) fibrils. The microstructure evolution and nano-mechanical properties of Aβ(1-40) fibrils during the disassembly process were systematically investigated by the Peak Force Quantitative Nano-mechanical (PF-QNM) technique. The results show an obvious decrease in Young's modulus of mature fibrils with high β-sheet contents (2.4 ± 1.0 GPa) in comparison to the resulting peptide/surfactant complexes (1.1 ± 0.8 GPa) with loose surface structures. Interestingly, the Young's modulus of spherical peptide/surfactant complexes on the core was more than 3 GPa. This strategy can be used as a standard protocol to investigate the interaction mechanism between amyloid fibrils and small molecules, which may open up new possibilities to explore the mechanism of relevant human diseases.

  17. Primary disassembly of Light Water Breeder Reactor modules for core evaluation (LWBR Development Program)

    SciTech Connect

    Greenberger, R.J.; Miller, E.L.

    1987-10-01

    After successfully operating for 29,047 effective full power hours, the Light Water Breeder Reactor (LWBR) core was defueled prior to total decommissioning of the Shippingport Atomic Power Station. All nuclear fuel and much of the reactor internal hardware was removed from the reactor vessel. Non-fuel components were prepared for shipment to disposal sites, and the fuel assemblies were partially disassembled and shipped to the Expended Core Facility (ECF) in Idaho. At ECF, the fuel modules underwent further disassembly to provide fuel rods for nondestructive testing to establish the core's breeding efficiency and to provide core components for examinations to assess their performance characteristics. This report presents a basic description of the processes and equipment used to disassemble LWBR fuel modules for subsequent proof-of-breeding (POB) and core examination operations. Included are discussions of module handling fixtures and equipment, the underwater milling machine and bandsaw assemblies, and the associated design and operation of this equipment for LWBR fuel module disassembly.

  18. Mechanical Disassembly of Single Virus Particles Reveals Kinetic Intermediates Predicted by Theory

    PubMed Central

    Castellanos, Milagros; Pérez, Rebeca; Carrillo, Pablo J.P.; de Pablo, Pedro J.; Mateu, Mauricio G.

    2012-01-01

    New experimental approaches are required to detect the elusive transient intermediates predicted by simulations of virus assembly or disassembly. Here, an atomic force microscope (AFM) was used to mechanically induce partial disassembly of single icosahedral T = 1 capsids and virions of the minute virus of mice. The kinetic intermediates formed were imaged by AFM. The results revealed that induced disassembly of single minute-virus-of-mice particles is frequently initiated by loss of one of the 20 equivalent capsomers (trimers of capsid protein subunits) leading to a stable, nearly complete particle that does not readily lose further capsomers. With lower frequency, a fairly stable, three-fourths-complete capsid lacking one pentamer of capsomers and a free, stable pentamer were obtained. The intermediates most frequently identified (capsids missing one capsomer, capsids missing one pentamer of capsomers, and free pentamers of capsomers) had been predicted in theoretical studies of reversible capsid assembly based on thermodynamic-kinetic models, molecular dynamics, or oligomerization energies. We conclude that mechanical manipulation and imaging of simple virus particles by AFM can be used to experimentally identify kinetic intermediates predicted by simulations of assembly or disassembly. PMID:22713577

  19. Shieldable tumor targeting based on pH responsive self-assembly/disassembly of gold nanoparticles.

    PubMed

    Tian, Zhiqing; Yang, Chengling; Wang, Wei; Yuan, Zhi

    2014-10-22

    A new approach to shield/deshield ligands for controllable tumor targeting was reported, which was based on amphiphilic self-assembly and disassembly of gold nanoparticles (Au NPs). Thanks to the excellent pH response of the system, glycyrrhetinic acid (GA) ligands can be buried inside the Au NPs' assembly at normal tissue pH (pH 7.4), while exposed when the nanostructure is disassembled at tumor extracellular pH (pHe 6.8). Hydrophobic GA molecules not only acted as ligands targeting tumor cells but also provided the major interparticle attractive force for Au NPs' assembling. An ordered assembly of Au NPs with regular shape, proper size and ultrasharp pH sensitivity (ΔpH ∼ 0.2) was achieved by fine-tuning of materials modified on Au NPs. Mechanism studies for assembly and disassembly of Au NPs indicated the possibility of a GA shield when the assembly formed, which was further demonstrated by bovine serum albumin absorption and cellular uptake. The assembly/disassembly process was reversible within extrinsic pH changes, which provides a perspective for reversible tumor targeting.

  20. Low cytoplasmic pH reduces ER-Golgi trafficking and induces disassembly of the Golgi apparatus

    SciTech Connect

    Soonthornsit, Jeerawat; Yamaguchi, Yoko; Tamura, Daisuke; Ishida, Ryuichi; Nakakoji, Yoko; Osako, Shiho; Yamamoto, Akitsugu; Nakamura, Nobuhiro

    2014-11-01

    The Golgi apparatus was dramatically disassembled when cells were incubated in a low pH medium. The cis-Golgi disassembled quickly, extended tubules and spread to the periphery of cells within 30 min. In contrast, medial- and trans-Golgi were fragmented in significantly larger structures of smaller numbers at a slower rate and remained largely in structures distinct from the cis-Golgi. Electron microscopy revealed the complete disassembly of the Golgi stack in low pH treated cells. The effect of low pH was reversible; the Golgi apparatus reassembled to form a normal ribbon-like structure within 1–2 h after the addition of a control medium. The anterograde ER to Golgi transport and retrograde Golgi to ER transport were both reduced under low pH. Phospholipase A{sub 2} inhibitors (ONO, BEL) effectively suppressed the Golgi disassembly, suggesting that the phospholipase A{sub 2} was involved in the Golgi disassembly. Over-expression of Rab1, 2, 30, 33 and 41 also suppressed the Golgi disassembly under low pH, suggesting that they have protective role against Golgi disassembly. Low pH treatment reduced cytoplasmic pH, but not the luminal pH of the Golgi apparatus, strongly suggesting that reduction of the cytoplasmic pH triggered the Golgi disassembly. Because a lower cytoplasmic pH is induced in physiological or pathological conditions, disassembly of the Golgi apparatus and reduction of vesicular transport through the Golgi apparatus may play important roles in cell physiology and pathology. Furthermore, our findings indicated that low pH treatment can serve as an important tool to analyze the molecular mechanisms that support the structure and function of the Golgi apparatus. - Highlights: • The Golgi apparatus reversibly disassembles by low pH treatment. • The cis-Golgi disassembles quickly generating tubular structures. • Both anterograde and retrograde transport between the ER and the Golgi apparatus are reduced. • Phospholipase A{sub 2} inhibitors (ONO

  1. Roles of different pools of the mitotic checkpoint complex and the mechanisms of their disassembly

    PubMed Central

    Eytan, Esther; Sitry-Shevah, Danielle; Teichner, Adar; Hershko, Avram

    2013-01-01

    The mitotic (or spindle assembly) checkpoint system prevents premature separation of sister chromatids in mitosis. When the checkpoint is turned on, the mitotic checkpoint complex (MCC) inhibits the ubiquitin ligase anaphase-promoting complex/cyclosome (APC/C). MCC is composed of the checkpoint proteins BubR1, Bub3, and Mad2 associated with the APC/C activator Cdc20. The mechanisms of the assembly of MCC when the checkpoint is turned on, and of its disassembly when the checkpoint is inactivated, are not sufficiently understood. Previous reports indicated that APC/C-mediated polyubiquitylation of Cdc20 in MCC is required for the dissociation of APC/C-associated MCC, but not of free MCC. The pool of free MCC is disassembled by an ATP-dependent process stimulated by the Mad2-binding protein p31comet. It remained unknown whether free MCC is the precursor or the dissociation product of APC/C-bound MCC. By characterizing the mechanisms of the disassembly of APC/C-bound MCC in a purified system, we find that it cannot be the source of free MCC, because it is bound at high affinity and is released only in ubiquitylated or partially disassembled forms. By the use of a cell-free system from Xenopus eggs that reproduces the mitotic checkpoint, we show that MCC can be assembled in the absence of APC/C in a checkpoint-dependent manner. We propose that when the checkpoint is turned on, free MCC is the precursor of APC/C-bound MCC. When the mitotic checkpoint is extinguished, both APC/C-bound and free MCC pools have to be disassembled to release APC/C from inhibition. PMID:23754430

  2. Disassembly and physical separation of electric/electronic components layered in printed circuit boards (PCB).

    PubMed

    Lee, Jaeryeong; Kim, Youngjin; Lee, Jae-chun

    2012-11-30

    Although printed circuit boards (PCBs) contain various elements, only the major elements (i.e., those with content levels in wt% or over grade) of and precious metals (e.g., Ag, Au, and platinum groups) contained within PCBs can be recycled. To recover other elements from PCBs, the PCBs should be properly disassembled as the first step of the recycling process. The recovery of these other elements would be beneficial for efforts to conserve scarce resources, reuse electric/electronic components (EECs), and eliminate environmental problems. This paper examines the disassembly of EECs from wasted PCBs (WPCBs) and the physical separation of these EECs using a self-designed disassembling apparatus and a 3-step separation process of sieving, magnetic separation, and dense medium separation. The disassembling efficiencies were evaluated by using the ratio of grinding area (E(area)) and the weight ratio of the detached EECs (E(weight)). In the disassembly treatment, these efficiencies were improved with an increase of grinder speed and grinder height. 97.7% (E(area)) and 98% (E(weight)) could be accomplished ultimately by 3 repetitive treatments at a grinder speed of 5500 rpm and a grinder height of 1.5mm. Through a series of physical separations, most groups of the EECs (except for the diode, transistor, and IC chip groups) could be sorted at a relatively high separation efficiency of about 75% or more. To evaluate the separation efficiency with regard to the elemental composition, the distribution ratio (R(dis)) and the concentration ratio (R(conc)) were used. 15 elements could be separated with the highest R(dis) and R(conc) in the same separated division. This result implies that the recyclability of the elements is highly feasible, even though the initial content in EECs is lower than several tens of mg/kg.

  3. Link of NTR-Mediated Spliceosome Disassembly with DEAH-Box ATPases Prp2, Prp16, and Prp22

    PubMed Central

    Chen, Hsin-Chou; Tseng, Chi-Kang; Tsai, Rong-Tzong; Chung, Che-Sheng

    2013-01-01

    The DEAH-box ATPase Prp43 is required for disassembly of the spliceosome after the completion of splicing or after the discard of the spliceosome due to a splicing defect. Prp43 associates with Ntr1 and Ntr2 to form the NTR complex and is recruited to the spliceosome via the interaction of Ntr2 and U5 component Brr2. Ntr2 alone can bind to U5 and to the spliceosome. To understand how NTR might mediate the disassembly of spliceosome intermediates, we arrested the spliceosome at various stages of the assembly pathway and assessed its susceptibility to disassembly. We found that NTR could catalyze the disassembly of affinity-purified spliceosomes arrested specifically after the ATP-dependent action of DEAH-box ATPase Prp2, Prp16, or Prp22 but not at steps before the action of these ATPases or upon their binding to the spliceosome. These results link spliceosome disassembly to the functioning of splicing ATPases. Analysis of the binding of Ntr2 to each splicing complex has revealed that the presence of Prp16 and Slu7, which also interact with Brr2, has a negative impact on Ntr2 binding. Our study provides insights into the mechanism by which NTR can be recruited to the spliceosome to mediate the disassembly of spliceosome intermediates when the spliceosome pathway is retarded, while disassembly is prevented in normal reactions. PMID:23166295

  4. Low cytoplasmic pH reduces ER-Golgi trafficking and induces disassembly of the Golgi apparatus.

    PubMed

    Soonthornsit, Jeerawat; Yamaguchi, Yoko; Tamura, Daisuke; Ishida, Ryuichi; Nakakoji, Yoko; Osako, Shiho; Yamamoto, Akitsugu; Nakamura, Nobuhiro

    2014-11-01

    The Golgi apparatus was dramatically disassembled when cells were incubated in a low pH medium. The cis-Golgi disassembled quickly, extended tubules and spread to the periphery of cells within 30 min. In contrast, medial- and trans-Golgi were fragmented in significantly larger structures of smaller numbers at a slower rate and remained largely in structures distinct from the cis-Golgi. Electron microscopy revealed the complete disassembly of the Golgi stack in low pH treated cells. The effect of low pH was reversible; the Golgi apparatus reassembled to form a normal ribbon-like structure within 1-2h after the addition of a control medium. The anterograde ER to Golgi transport and retrograde Golgi to ER transport were both reduced under low pH. Phospholipase A2 inhibitors (ONO, BEL) effectively suppressed the Golgi disassembly, suggesting that the phospholipase A2 was involved in the Golgi disassembly. Over-expression of Rab1, 2, 30, 33 and 41 also suppressed the Golgi disassembly under low pH, suggesting that they have protective role against Golgi disassembly. Low pH treatment reduced cytoplasmic pH, but not the luminal pH of the Golgi apparatus, strongly suggesting that reduction of the cytoplasmic pH triggered the Golgi disassembly. Because a lower cytoplasmic pH is induced in physiological or pathological conditions, disassembly of the Golgi apparatus and reduction of vesicular transport through the Golgi apparatus may play important roles in cell physiology and pathology. Furthermore, our findings indicated that low pH treatment can serve as an important tool to analyze the molecular mechanisms that support the structure and function of the Golgi apparatus.

  5. AGR-1 Irradiated Test Train Preliminary Inspection and Disassembly First Look

    SciTech Connect

    Paul Demkowicz; Lance Cole; Scott Ploger; Philip Winston; Binh Pham; Michael Abbott

    2011-01-01

    The AGR-1 irradiation experiment ended on November 6, 2009, after 620 effective full power days in the Advanced Test Reactor, achieving a peak burnup of 19.6% FIMA. The test train was shipped to the Materials and Fuels Complex in March 2010 for post-irradiation examination. The first PIE activities included non-destructive examination of the test train, followed by disassembly of the test train and individual capsules and detailed inspection of the capsule contents, including the fuel compacts and the graphite fuel holders. Dimensional measurements of the compacts, graphite holders, and steel capsules shells were performed using a custom vision measurement system (for outer diameters and lengths) and conventional bore gauges (for inner diameters). Gamma spectrometry of the intact test train gave a preliminary look at the condition of the interior components. No evidence of damage to compacts or graphite components was evident from the isotopic and gross gamma scans. Neutron radiography of the intact Capsule 2 showed a high degree of detail of interior components and confirmed the observation that there was no major damage to the capsule. Disassembly of the capsules was initiated using procedures qualified during out-of-cell mockup testing. Difficulties were encountered during capsule disassembly due to irradiation-induced changes in some of the capsule components’ properties, including embrittled niobium and molybdenum parts that were susceptible to fracture and swelling of the graphite fuel holders that affected their removal from the capsule shells. This required various improvised modifications to the disassembly procedure to avoid damage to the fuel compacts. Ultimately the capsule disassembly was successful and only one compact from Capsule 4 (out of 72 total in the test train) sustained damage during the disassembly process, along with the associated graphite holder. The compacts were generally in very good condition upon removal. Only relatively minor

  6. Assembly, operation and disassembly manual for the Battelle Large Volume Water Sampler (BLVWS)

    SciTech Connect

    Thomas, V.W.; Campbell, R.M.

    1984-12-01

    Assembly, operation and disassembly of the Battelle Large Volume Water Sampler (BLVWS) are described in detail. Step by step instructions of assembly, general operation and disassembly are provided to allow an operator completely unfamiliar with the sampler to successfully apply the BLVWS to his research sampling needs. The sampler permits concentration of both particulate and dissolved radionuclides from large volumes of ocean and fresh water. The water sample passes through a filtration section for particle removal then through sorption or ion exchange beds where species of interest are removed. The sampler components which contact the water being sampled are constructed of polyvinylchloride (PVC). The sampler has been successfully applied to many sampling needs over the past fifteen years. 9 references, 8 figures.

  7. Chlamydomonas shortens its flagella by activating axonemal disassembly, stimulating IFT particle trafficking, and blocking anterograde cargo loading.

    PubMed

    Pan, Junmin; Snell, William J

    2005-09-01

    Almost all eukaryotic cells form cilia/flagella, maintain them at their genetically specified lengths, and shorten them. Here, we define the cellular mechanisms that bring about shortening of flagella prior to meiotic cell division and in response to environmental cues in the biflagellated green alga Chlamydomonas. We show that the flagellar shortening pathway is distinct from the one that enforces transient shortening essential for length control. During flagellar shortening, disassembly of the axoneme is stimulated over the basal rate, and the rate of entry into flagella of intraflagellar transport (IFT) particles is increased. Moreover, the particles entering the disassembling flagella lack cargo. Thus, flagellar shortening depends on the interplay between dynamic properties of the axoneme and the IFT machinery; a cell triggered to shorten its flagellum activates disassembly of the axoneme and stimulates entry into the flagellum of IFT particles possessing empty cargo binding sites available to retrieve the disassembled components.

  8. Detailed Per-residue Energetic Analysis Explains the Driving Force for Microtubule Disassembly.

    PubMed

    Ayoub, Ahmed T; Klobukowski, Mariusz; Tuszynski, Jack A

    2015-06-01

    Microtubules are long filamentous hollow cylinders whose surfaces form lattice structures of αβ-tubulin heterodimers. They perform multiple physiological roles in eukaryotic cells and are targets for therapeutic interventions. In our study, we carried out all-atom molecular dynamics simulations for arbitrarily long microtubules that have either GDP or GTP molecules in the E-site of β-tubulin. A detailed energy balance of the MM/GBSA inter-dimer interaction energy per residue contributing to the overall lateral and longitudinal structural stability was performed. The obtained results identified the key residues and tubulin domains according to their energetic contributions. They also identified the molecular forces that drive microtubule disassembly. At the tip of the plus end of the microtubule, the uneven distribution of longitudinal interaction energies within a protofilament generates a torque that bends tubulin outwardly with respect to the cylinder's axis causing disassembly. In the presence of GTP, this torque is opposed by lateral interactions that prevent outward curling, thus stabilizing the whole microtubule. Once GTP hydrolysis reaches the tip of the microtubule (lateral cap), lateral interactions become much weaker, allowing tubulin dimers to bend outwards, causing disassembly. The role of magnesium in the process of outward curling has also been demonstrated. This study also showed that the microtubule seam is the most energetically labile inter-dimer interface and could serve as a trigger point for disassembly. Based on a detailed balance of the energetic contributions per amino acid residue in the microtubule, numerous other analyses could be performed to give additional insights into the properties of microtubule dynamic instability.

  9. Detailed Per-residue Energetic Analysis Explains the Driving Force for Microtubule Disassembly

    PubMed Central

    Ayoub, Ahmed T.; Klobukowski, Mariusz; Tuszynski, Jack A.

    2015-01-01

    Microtubules are long filamentous hollow cylinders whose surfaces form lattice structures of αβ-tubulin heterodimers. They perform multiple physiological roles in eukaryotic cells and are targets for therapeutic interventions. In our study, we carried out all-atom molecular dynamics simulations for arbitrarily long microtubules that have either GDP or GTP molecules in the E-site of β-tubulin. A detailed energy balance of the MM/GBSA inter-dimer interaction energy per residue contributing to the overall lateral and longitudinal structural stability was performed. The obtained results identified the key residues and tubulin domains according to their energetic contributions. They also identified the molecular forces that drive microtubule disassembly. At the tip of the plus end of the microtubule, the uneven distribution of longitudinal interaction energies within a protofilament generates a torque that bends tubulin outwardly with respect to the cylinder's axis causing disassembly. In the presence of GTP, this torque is opposed by lateral interactions that prevent outward curling, thus stabilizing the whole microtubule. Once GTP hydrolysis reaches the tip of the microtubule (lateral cap), lateral interactions become much weaker, allowing tubulin dimers to bend outwards, causing disassembly. The role of magnesium in the process of outward curling has also been demonstrated. This study also showed that the microtubule seam is the most energetically labile inter-dimer interface and could serve as a trigger point for disassembly. Based on a detailed balance of the energetic contributions per amino acid residue in the microtubule, numerous other analyses could be performed to give additional insights into the properties of microtubule dynamic instability. PMID:26030285

  10. Molecular disassembly of rice and lotus starches during thermal processing and its effect on starch digestibility.

    PubMed

    Wang, Shujun; Sun, Yue; Wang, Jinrong; Wang, Shuo; Copeland, Les

    2016-02-01

    The molecular disassembly of starch during thermal processing is a major determinant for the susceptibility of starch to enzymatic digestion. In the present study, the effects of thermal processing on the disassembly of the granular structure and the in vitro enzymatic digestibility of rice and lotus starches were investigated. After heating at 50 °C, rice and lotus starches did not show significant changes in granular morphology, long-range crystallinity and short-range molecular order. As the temperature increased to 60 °C, rice starch underwent a partial gelatinization followed by an incomplete disruption of granular morphology, crystallites and molecular order. In contrast, lotus starch was almost completely gelatinized at 60 °C. At 70 °C or higher, both starches were fully gelatinized with complete disruption of the micro and macro structures. Our results show that gelatinization greatly increased the in vitro enzymatic digestibility of both starches, but that the degree of disassembly of the starch structure during thermal processing was not a major determinant of the digestibility of gelatinized starch.

  11. Artificial biofilms establish the role of matrix interactions in staphylococcal biofilm assembly and disassembly.

    PubMed

    Stewart, Elizabeth J; Ganesan, Mahesh; Younger, John G; Solomon, Michael J

    2015-08-14

    We demonstrate that the microstructural and mechanical properties of bacterial biofilms can be created through colloidal self-assembly of cells and polymers, and thereby link the complex material properties of biofilms to well understood colloidal and polymeric behaviors. This finding is applied to soften and disassemble staphylococcal biofilms through pH changes. Bacterial biofilms are viscoelastic, structured communities of cells encapsulated in an extracellular polymeric substance (EPS) comprised of polysaccharides, proteins, and DNA. Although the identity and abundance of EPS macromolecules are known, how these matrix materials interact with themselves and bacterial cells to generate biofilm morphology and mechanics is not understood. Here, we find that the colloidal self-assembly of Staphylococcus epidermidis RP62A cells and polysaccharides into viscoelastic biofilms is driven by thermodynamic phase instability of EPS. pH conditions that induce phase instability of chitosan produce artificial S. epidermidis biofilms whose mechanics match natural S. epidermidis biofilms. Furthermore, pH-induced solubilization of the matrix triggers disassembly in both artificial and natural S. epidermidis biofilms. This pH-induced disassembly occurs in biofilms formed by five additional staphylococcal strains, including three clinical isolates. Our findings suggest that colloidal self-assembly of cells and matrix polymers produces biofilm viscoelasticity and that biofilm control strategies can exploit this mechanism.

  12. Design-only conceptual design report for pit disassembly and conversion facility. Rev 0

    SciTech Connect

    Zygmunt, S.; Christensen, L.; Richardson, C.

    1997-12-12

    This design-only conceptual design report (DOCDR) was prepared to support a funding request by the Department of Energy (DOE)-Office of Fissile Material Disposition (OFMD) for engineering design of the Pit Disassembly and Conversion Facility (PDCF) Project No. 99-D-141. The PDCF will be used to disassemble the nation`s inventory of surplus nuclear weapons pits and convert the plutonium recovered from those pits into a form suitable for storage, international inspection, and final disposition. The PDCF is a complex consisting of a hardened building that will contain the plutonium processes in a safe and secure manner, and conventional buildings and structures that will house support personnel, systems, and equipment. The PDCF uses the Advanced Recovery and Integrated Extraction System (ARIES), a low waste, modular pyroprocessing system to convert pits to plutonium oxide. The PDCF project consists of engineering and design, and construction of the buildings and structures, and engineering and design, procurement, installation, testing and start-up of equipment to disassemble pits and convert plutonium in pits to oxide form. The facility is planned to operate for 10 years, averaging 3.5 metric tons (3.86 tons) of plutonium metal per year. On conclusion of operations, the PDCF will be decontaminated and decommissioned.

  13. Myosin-dependent remodeling of adherens junctions protects junctions from Snail-dependent disassembly

    PubMed Central

    Weng, Mo

    2016-01-01

    Although Snail is essential for disassembly of adherens junctions during epithelial–mesenchymal transitions (EMTs), loss of adherens junctions in Drosophila melanogaster gastrula is delayed until mesoderm is internalized, despite the early expression of Snail in that primordium. By combining live imaging and quantitative image analysis, we track the behavior of E-cadherin–rich junction clusters, demonstrating that in the early stages of gastrulation most subapical clusters in mesoderm not only persist, but move apically and enhance in density and total intensity. All three phenomena depend on myosin II and are temporally correlated with the pulses of actomyosin accumulation that drive initial cell shape changes during gastrulation. When contractile myosin is absent, the normal Snail expression in mesoderm, or ectopic Snail expression in ectoderm, is sufficient to drive early disassembly of junctions. In both cases, junctional disassembly can be blocked by simultaneous induction of myosin contractility. Our findings provide in vivo evidence for mechanosensitivity of cell–cell junctions and imply that myosin-mediated tension can prevent Snail-driven EMT. PMID:26754645

  14. CENP-A and H3 Nucleosomes Display a Similar Stability to Force-Mediated Disassembly

    PubMed Central

    Kim, Sung Hyun; Vlijm, Rifka; van der Torre, Jaco; Dalal, Yamini; Dekker, Cees

    2016-01-01

    Centromere-specific nucleosomes are a central feature of the kinetochore complex during mitosis, in which microtubules exert pulling and pushing forces upon the centromere. CENP-A nucleosomes have been assumed to be structurally unique, thereby providing resilience under tension relative to their H3 canonical counterparts. Here, we directly test this hypothesis by subjecting CENP-A and H3 octameric nucleosomes, assembled on random or on centromeric DNA sequences, to varying amounts of applied force by using single-molecule magnetic tweezers. We monitor individual disassembly events of CENP-A and H3 nucleosomes. Regardless of the DNA sequence, the force-mediated disassembly experiments for CENP-A and H3 nucleosomes demonstrate similar rupture forces, life time residency and disassembly steps. From these experiments, we conclude that CENP-A does not, by itself, contribute unique structural features to the nucleosome that lead to a significant resistance against force-mediated disruption. The data present insights into the mechanistic basis for how CENP-A nucleosomes might contribute to the structural foundation of the centromere in vivo. PMID:27820823

  15. Single-molecule imaging of a three-component ordered actin disassembly mechanism

    PubMed Central

    Jansen, Silvia; Collins, Agnieszka; Chin, Samantha M.; Ydenberg, Casey A.; Gelles, Jeff; Goode, Bruce L.

    2015-01-01

    The mechanisms by which cells destabilize and rapidly disassemble filamentous actin networks have remained elusive; however, Coronin, Cofilin and AIP1 have been implicated in this process. Here using multi-wavelength single-molecule fluorescence imaging, we show that mammalian Cor1B, Cof1 and AIP1 work in concert through a temporally ordered pathway to induce highly efficient severing and disassembly of actin filaments. Cor1B binds to filaments first, and dramatically accelerates the subsequent binding of Cof1, leading to heavily decorated, stabilized filaments. Cof1 in turn recruits AIP1, which rapidly triggers severing and remains bound to the newly generated barbed ends. New growth at barbed ends generated by severing was blocked specifically in the presence of all three proteins. This activity enabled us to reconstitute and directly visualize single actin filaments being rapidly polymerized by formins at their barbed ends while simultanteously being stochastically severed and capped along their lengths, and disassembled from their pointed ends. PMID:25995115

  16. Overlapping mechanisms promote postsynaptic RAD-51 filament disassembly during meiotic double-strand break repair.

    PubMed

    Ward, Jordan D; Muzzini, Diego M; Petalcorin, Mark I R; Martinez-Perez, Enrique; Martin, Julie S; Plevani, Paolo; Cassata, Giuseppe; Marini, Federica; Boulton, Simon J

    2010-01-29

    Homologous recombination (HR) is essential for repair of meiotic DNA double-strand breaks (DSBs). Although the mechanisms of RAD-51-DNA filament assembly and strand exchange are well characterized, the subsequent steps of HR are less well defined. Here, we describe a synthetic lethal interaction between the C. elegans helicase helq-1 and RAD-51 paralog rfs-1, which results in a block to meiotic DSB repair after strand invasion. Whereas RAD-51-ssDNA filaments assemble at meiotic DSBs with normal kinetics in helq-1, rfs-1 double mutants, persistence of RAD-51 foci and genetic interactions with rtel-1 suggest a failure to disassemble RAD-51 from strand invasion intermediates. Indeed, purified HELQ-1 and RFS-1 independently bind to and promote the disassembly of RAD-51 from double-stranded, but not single-stranded, DNA filaments via distinct mechanisms in vitro. These results indicate that two compensating activities are required to promote postsynaptic RAD-51 filament disassembly, which are collectively essential for completion of meiotic DSB repair.

  17. Light-induced disassembly of self-assembled vesicle-capped nanotubes observed in real time

    NASA Astrophysics Data System (ADS)

    Coleman, Anthony C.; Beierle, John M.; Stuart, Marc C. A.; Maciá, Beatriz; Caroli, Giuseppe; Mika, Jacek T.; van Dijken, Derk Jan; Chen, Jiawen; Browne, Wesley R.; Feringa, Ben L.

    2011-09-01

    Molecular self-assembly is the basis for the formation of numerous artificial nanostructures. The self-organization of peptides, amphiphilic molecules composed of fused benzene rings and other functional molecules into nanotubes is of particular interest. However, the design of dynamic, complex self-organized systems that are responsive to external stimuli remains a significant challenge. Here, we report self-assembled, vesicle-capped nanotubes that can be selectively disassembled by irradiation. The walls of the nanotubes are 3-nm-thick bilayers and are made from amphiphilic molecules with two hydrophobic legs that interdigitate when the molecules self-assemble into bilayers. In the presence of phospholipids, a phase separation between the phospholipids and the amphiphilic molecules creates nanotubes, which are end-capped by vesicles that can be chemically altered or removed and reattached without affecting the nanotubes. The presence of a photoswitchable and fluorescent core in the amphiphilic molecules allows fast and highly controlled disassembly of the nanotubes on irradiation, and distinct disassembly processes can be observed in real time using fluorescence microscopy.

  18. Disassembly of mitotic checkpoint complexes by the joint action of the AAA-ATPase TRIP13 and p31comet

    PubMed Central

    Eytan, Esther; Wang, Kexi; Miniowitz-Shemtov, Shirly; Sitry-Shevah, Danielle; Kaisari, Sharon; Yen, Tim J.; Liu, Song-Tao; Hershko, Avram

    2014-01-01

    The mitotic (or spindle assembly) checkpoint system delays anaphase until all chromosomes are correctly attached to the mitotic spindle. When the checkpoint is active, a Mitotic Checkpoint Complex (MCC) assembles and inhibits the ubiquitin ligase Anaphase-Promoting Complex/Cyclosome (APC/C). MCC is composed of the checkpoint proteins Mad2, BubR1, and Bub3 associated with the APC/C activator Cdc20. When the checkpoint signal is turned off, MCC is disassembled and the checkpoint is inactivated. The mechanisms of the disassembly of MCC are not sufficiently understood. We have previously observed that ATP hydrolysis is required for the action of the Mad2-binding protein p31comet to disassemble MCC. We now show that HeLa cell extracts contain a factor that promotes ATP- and p31comet-dependent disassembly of a Cdc20–Mad2 subcomplex and identify it as Thyroid Receptor Interacting Protein 13 (TRIP13), an AAA-ATPase known to interact with p31comet. The joint action of TRIP13 and p31comet also promotes the release of Mad2 from MCC, participates in the complete disassembly of MCC and abrogates checkpoint inhibition of APC/C. We propose that TRIP13 plays centrally important roles in the sequence of events leading to MCC disassembly and checkpoint inactivation. PMID:25092294

  19. AGR-2 Irradiated Test Train Preliminary Inspection and Disassembly First Look

    SciTech Connect

    Ploger, Scott; Demkowciz, Paul; Harp, Jason

    2015-05-01

    The AGR 2 irradiation experiment began in June 2010 and was completed in October 2013. The test train was shipped to the Materials and Fuels Complex in July 2014 for post-irradiation examination (PIE). The first PIE activities included nondestructive examination of the test train, followed by disassembly of the test train and individual capsules and detailed inspection of the capsule contents, including the fuel compacts and their graphite fuel holders. Dimensional metrology was then performed on the compacts, graphite holders, and steel capsule shells. AGR 2 disassembly and metrology were performed with the same equipment used successfully on AGR 1 test train components. Gamma spectrometry of the intact test train gave a preliminary look at the condition of the interior components. No evidence of damage to compacts or graphite components was evident from the isotopic and gross gamma scans. Disassembly of the AGR 2 test train and its capsules was conducted rapidly and efficiently by employing techniques refined during the AGR 1 disassembly campaign. Only one major difficulty was encountered while separating the test train into capsules when thermocouples (of larger diameter than used in AGR 1) and gas lines jammed inside the through tubes of the upper capsules, which required new tooling for extraction. Disassembly of individual capsules was straightforward with only a few minor complications. On the whole, AGR 2 capsule structural components appeared less embrittled than their AGR 1 counterparts. Compacts from AGR 2 Capsules 2, 3, 5, and 6 were in very good condition upon removal. Only relatively minor damage or markings were visible using high resolution photographic inspection. Compact dimensional measurements indicated radial shrinkage between 0.8 to 1.7%, with the greatest shrinkage observed on Capsule 2 compacts that were irradiated at higher temperature. Length shrinkage ranged from 0.1 to 0.9%, with by far the lowest axial shrinkage on Capsule 3 compacts

  20. Fruit softening and pectin disassembly: an overview of nanostructural pectin modifications assessed by atomic force microscopy

    PubMed Central

    Paniagua, Candelas; Posé, Sara; Morris, Victor J.; Kirby, Andrew R.; Quesada, Miguel A.; Mercado, José A.

    2014-01-01

    Background One of the main factors that reduce fruit quality and lead to economically important losses is oversoftening. Textural changes during fruit ripening are mainly due to the dissolution of the middle lamella, the reduction of cell-to-cell adhesion and the weakening of parenchyma cell walls as a result of the action of cell wall modifying enzymes. Pectins, major components of fruit cell walls, are extensively modified during ripening. These changes include solubilization, depolymerization and the loss of neutral side chains. Recent evidence in strawberry and apple, fruits with a soft or crisp texture at ripening, suggests that pectin disassembly is a key factor in textural changes. In both these fruits, softening was reduced as result of antisense downregulation of polygalacturonase genes. Changes in pectic polymer size, composition and structure have traditionally been studied by conventional techniques, most of them relying on bulk analysis of a population of polysaccharides, and studies focusing on modifications at the nanostructural level are scarce. Atomic force microscopy (AFM) allows the study of individual polymers at high magnification and with minimal sample preparation; however, AFM has rarely been employed to analyse pectin disassembly during fruit ripening. Scope In this review, the main features of the pectin disassembly process during fruit ripening are first discussed, and then the nanostructural characterization of fruit pectins by AFM and its relationship with texture and postharvest fruit shelf life is reviewed. In general, fruit pectins are visualized under AFM as linear chains, a few of which show long branches, and aggregates. Number- and weight-average values obtained from these images are in good agreement with chromatographic analyses. Most AFM studies indicate reductions in the length of individual pectin chains and the frequency of aggregates as the fruits ripen. Pectins extracted with sodium carbonate, supposedly located within

  1. Late Disassembly of Femoral Head and Neck of A Modular Primary Total Hip Arthroplasty

    PubMed Central

    Ahmed, Parvej; Kumar, Dinesh

    2015-01-01

    Introduction: Modular total hip arthroplasty system are now widely used, as these components increase the flexibility during primary and revision total hip arthoplasty. But this modularity itself associated with some risk of intraoperative and postoperative complications. Case Report: We report a case of late disassembly of a primary total arthroplasty in a 42 years old patient five years after the replacement surgery where the femoral head remained in the acetabular socket. Conclusion: Femoral head should be solidly impacted onto the stem and confirm that it has been assembled correctly before reduction. PMID:27299010

  2. Fractional processes and nuclear disassembly in very-heavy-ion collisions in the Fermi energy regime

    SciTech Connect

    Schroeder, W.U.

    1991-01-01

    Exclusive measurements of charged products and neutrons were performed for the reactions {sup 197}Au + (29 MeV/u) {sup 208}Pb and {sup 209}Bi + (28.2 MeV/u) {sup 136}Xe. The multiplicities of neutrons and charged particles are found to indicate collision impact parameters with different sensitivities. Characteristic correlations observed between massive products and light particles suggest the dominance of the damped-reaction mechanism in the Fermi energy domain. For central collisions, massive fragments are no longer observed, and a considerable fraction of the mass of the system is found disassembled into light particles and clusters. 75 refs., 19 figs.

  3. Demonstrate fuel disassembly/encapsulation. Technical progress report, April 1981-June 1981

    SciTech Connect

    1981-08-03

    Work on this project is focused on demonstrating disassembly and encapsulation of nuclear fuels as a means to increase spent fuel storage. The effort commenced on April 17, 1980, and is progressing satisfactorily. The Equipment/Procedure Preparation sub-task is essentially complete. The Equipment Demonstration sub-task and the Process Assessment Studies sub-task continue. The equipment design effort associated with the first sub-task, the component testing and checking associated with the second sub-task, and the technical studies and investigations associated with the latter sub-task continue to verify the feasibility of this concept to enhance the use of fuel storage resources.

  4. Uninformed and probabilistic distributed agent combinatorial searches for the unary NP-complete disassembly line balancing problem

    NASA Astrophysics Data System (ADS)

    McGovern, Seamus M.; Gupta, Surendra M.

    2005-11-01

    Disassembly takes place in remanufacturing, recycling, and disposal, with a line being the best choice for automation. The disassembly line balancing problem seeks a sequence which: is feasible, minimizes workstations, and ensures similar idle times, as well as other end-of-life specific concerns. Finding the optimal balance is computationally intensive due to exponential growth. Combinatorial optimization methods hold promise for providing solutions to the disassembly line balancing problem, which is proven here to belong to the class of unary NP-complete problems. Probabilistic (ant colony optimization) and uninformed (H-K) search methods are presented and compared. Numerical results are obtained using a recent case study to illustrate the search implementations and compare their performance. Conclusions drawn include the consistent generation of near-optimal solutions, the ability to preserve precedence, the speed of the techniques, and their practicality due to ease of implementation.

  5. Repeated Cycles of Rapid Actin Assembly and Disassembly on Epithelial Cell PhagosomesV⃞

    PubMed Central

    Yam, Patricia T.; Theriot, Julie A.

    2004-01-01

    We have found that early in infection of the intracellular pathogen Listeria monocytogenes in Madin-Darby canine kidney epithelial cells expressing actin conjugated to green fluorescent protein, F-actin rapidly assembles (∼25 s) and disassembles (∼30 s) around the bacteria, a phenomenon we call flashing. L. monocytogenes strains unable to perform actin-based motility or unable to escape the phagosome were capable of flashing, suggesting that the actin assembly occurs on the phagosome membrane. Cycles of actin assembly and disassembly could occur repeatedly on the same phagosome. Indirect immunofluorescence showed that most bacteria were fully internalized when flashing occurred, suggesting that actin flashing does not represent phagocytosis. Escherichia coli expressing invA, a gene product from Yersinia pseudotuberculosis that mediates cellular invasion, also induced flashing. Furthermore, polystyrene beads coated with E-cadherin or transferrin also induced flashing after internalization. This suggests that flashing occurs downstream of several distinct molecular entry mechanisms and may be a general consequence of internalization of large objects by epithelial cells. PMID:15456901

  6. Molecular disassembly of starch granules during gelatinization and its effect on starch digestibility: a review.

    PubMed

    Wang, Shujun; Copeland, Les

    2013-11-01

    Starch is the most important glycemic carbohydrate in foods. The relationship between the rate and extent of starch digestion to produce glucose for absorption into the bloodstream and risk factors for diet-related diseases is of considerable nutritional interest. Native starch is attacked slowly by enzymes, but after hydrothermal processing its susceptibility to enzymatic breakdown is greatly increased. Most starch consumed by humans has undergone some form of processing or cooking, which causes native starch granules to gelatinize, followed by retrogradation on cooling. The extent of gelatinization and retrogradation are major determinants of the susceptibility of starch to enzymatic digestion and its functional properties for food processing. The type and extent of changes that occur in starch as a result of gelatinization, pasting and retrogradation are determined by the type of the starch, processing and storage conditions. A mechanistic understanding of the molecular disassembly of starch granules during gelatinization is critical to explaining the effects of processing or cooking on starch digestibility. This review focuses on the molecular disassembly of starch granules during starch gelatinization over a wide range of water levels, and its consequential effect on in vitro starch digestibility and in vivo glycemic index.

  7. Synthesis of Zeolites Using the ADOR (Assembly-Disassembly-Organization-Reassembly) Route.

    PubMed

    Wheatley, Paul S; Čejka, Jiří; Morris, Russell E

    2016-04-03

    Zeolites are an important class of materials that have wide ranging applications such as heterogeneous catalysts and adsorbents which are dependent on their framework topology. For new applications or improvements to existing ones, new zeolites with novel pore systems are desirable. We demonstrate a method for the synthesis of novel zeolites using the ADOR route. ADOR is an acronym for Assembly, Disassembly, Organization and Reassembly. This synthetic route takes advantage of the assembly of a relatively poorly stable that which can be selectively disassembled into a layered material. The resulting layered intermediate can then be organized in different manners by careful chemical manipulation and then reassembled into zeolites with new topologies. By carefully controlling the organization step of the synthetic pathway, new zeolites with never before seen topologies are capable of being synthesized. The structures of these new zeolites are confirmed using powder X-ray diffraction and further characterized by nitrogen adsorption and scanning electron microscopy. This new synthetic pathway for zeolites demonstrates its capability to produce novel frameworks that have never been prepared by traditional zeolite synthesis techniques.

  8. Reversible Guest Uptake/Release by Redox-Controlled Assembly/Disassembly of a Coordination Cage.

    PubMed

    Croué, Vincent; Goeb, Sébastien; Szalóki, György; Allain, Magali; Sallé, Marc

    2016-01-26

    Controlling the guest expulsion process from a receptor is of critical importance in various fields. Several coordination cages have been recently designed for this purpose, based on various types of stimuli to induce the guest release. Herein, we report the first example of a redox-triggered process from a coordination cage. The latter integrates a cavity, the panels of which are based on the extended tetrathiafulvalene unit (exTTF). The unique combination of electronic and conformational features of this framework (i.e. high π-donating properties and drastic conformational changes upon oxidation) allows the reversible disassembly/reassembly of the redox-active cavity upon chemical oxidation/reduction, respectively. This cage is able to bind the three-dimensional B12 F12 (2-) anion in a 1:2 host/guest stoichiometry. The reversible redox-triggered disassembly of the cage could also be demonstrated in the case of the host-guest complex, offering a new option for guest-delivering control.

  9. PslG, a self-produced glycosyl hydrolase, triggers biofilm disassembly by disrupting exopolysaccharide matrix

    PubMed Central

    Yu, Shan; Su, Tiantian; Wu, Huijun; Liu, Shiheng; Wang, Di; Zhao, Tianhu; Jin, Zengjun; Du, Wenbin; Zhu, Mei-Jun; Chua, Song Lin; Yang, Liang; Zhu, Deyu; Gu, Lichuan; Ma, Luyan Z

    2015-01-01

    Biofilms are surface-associated communities of microorganism embedded in extracellular matrix. Exopolysaccharide is a critical component in the extracellular matrix that maintains biofilm architecture and protects resident biofilm bacteria from antimicrobials and host immune attack. However, self-produced factors that target the matrix exopolysaccharides, are still poorly understood. Here, we show that PslG, a protein involved in the synthesis of a key biofilm matrix exopolysaccharide Psl in Pseudomonas aeruginosa, prevents biofilm formation and disassembles existing biofilms within minutes at nanomolar concentrations when supplied exogenously. The crystal structure of PslG indicates the typical features of an endoglycosidase. PslG mainly disrupts the Psl matrix to disperse bacteria from biofilms. PslG treatment markedly enhances biofilm sensitivity to antibiotics and macrophage cells, resulting in improved biofilm clearance in a mouse implant infection model. Furthermore, PslG shows biofilm inhibition and disassembly activity against a wide range of Pseudomonas species, indicating its great potential in combating biofilm-related complications. PMID:26611635

  10. Asymmetric ring structure of Vps4 required for ESCRT-III disassembly

    NASA Astrophysics Data System (ADS)

    Caillat, Christophe; Macheboeuf, Pauline; Wu, Yuanfei; McCarthy, Andrew A.; Boeri-Erba, Elisabetta; Effantin, Gregory; Göttlinger, Heinrich G.; Weissenhorn, Winfried; Renesto, Patricia

    2015-12-01

    The vacuolar protein sorting 4 AAA-ATPase (Vps4) recycles endosomal sorting complexes required for transport (ESCRT-III) polymers from cellular membranes. Here we present a 3.6-Å X-ray structure of ring-shaped Vps4 from Metallosphera sedula (MsVps4), seen as an asymmetric pseudohexamer. Conserved key interface residues are shown to be important for MsVps4 assembly, ATPase activity in vitro, ESCRT-III disassembly in vitro and HIV-1 budding. ADP binding leads to conformational changes within the protomer, which might propagate within the ring structure. All ATP-binding sites are accessible and the pseudohexamer binds six ATP with micromolar affinity in vitro. In contrast, ADP occupies one high-affinity and five low-affinity binding sites in vitro, consistent with conformational asymmetry induced on ATP hydrolysis. The structure represents a snapshot of an assembled Vps4 conformation and provides insight into the molecular motions the ring structure undergoes in a concerted action to couple ATP hydrolysis to ESCRT-III substrate disassembly.

  11. TLR ligand–induced podosome disassembly in dendritic cells is ADAM17 dependent

    PubMed Central

    West, Michele A.; Prescott, Alan R.; Chan, Kui Ming; Zhou, Zhongjun; Rose-John, Stefan; Scheller, Jürgen; Watts, Colin

    2008-01-01

    Toll-like receptor (TLR) signaling induces a rapid reorganization of the actin cytoskeleton in cultured mouse dendritic cells (DC), leading to enhanced antigen endocytosis and a concomitant loss of filamentous actin–rich podosomes. We show that as podosomes are lost, TLR signaling induces prominent focal contacts and a transient reduction in DC migratory capacity in vitro. We further show that podosomes in mouse DC are foci of pronounced gelatinase activity, dependent on the enzyme membrane type I matrix metalloprotease (MT1-MMP), and that DC transiently lose the ability to degrade the extracellular matrix after TLR signaling. Surprisingly, MMP inhibitors block TLR signaling–induced podosome disassembly, although stimulated endocytosis is unaffected, which demonstrates that the two phenomena are not obligatorily coupled. Podosome disassembly caused by TLR signaling occurs normally in DC lacking MT1-MMP, and instead requires the tumor necrosis factor α–converting enzyme ADAM17 (a disintegrin and metalloprotease 17), which demonstrates a novel role for this “sheddase” in regulating an actin-based structure. PMID:18762577

  12. Asymmetric ring structure of Vps4 required for ESCRT-III disassembly

    PubMed Central

    Caillat, Christophe; Macheboeuf, Pauline; Wu, Yuanfei; McCarthy, Andrew A.; Boeri-Erba, Elisabetta; Effantin, Gregory; Göttlinger, Heinrich G.; Weissenhorn, Winfried; Renesto, Patricia

    2015-01-01

    The vacuolar protein sorting 4 AAA–ATPase (Vps4) recycles endosomal sorting complexes required for transport (ESCRT-III) polymers from cellular membranes. Here we present a 3.6-Å X-ray structure of ring-shaped Vps4 from Metallosphera sedula (MsVps4), seen as an asymmetric pseudohexamer. Conserved key interface residues are shown to be important for MsVps4 assembly, ATPase activity in vitro, ESCRT-III disassembly in vitro and HIV-1 budding. ADP binding leads to conformational changes within the protomer, which might propagate within the ring structure. All ATP-binding sites are accessible and the pseudohexamer binds six ATP with micromolar affinity in vitro. In contrast, ADP occupies one high-affinity and five low-affinity binding sites in vitro, consistent with conformational asymmetry induced on ATP hydrolysis. The structure represents a snapshot of an assembled Vps4 conformation and provides insight into the molecular motions the ring structure undergoes in a concerted action to couple ATP hydrolysis to ESCRT-III substrate disassembly. PMID:26632262

  13. Disassembly of the reconstituted synaptic vesicle membrane fusion complex in vitro.

    PubMed Central

    Hayashi, T; Yamasaki, S; Nauenburg, S; Binz, T; Niemann, H

    1995-01-01

    The interaction of the presynaptic membrane proteins SNAP-25 and syntaxin with the synaptic vesicle protein synaptobrevin (VAMP) plays a key role in the regulated exocytosis of neurotransmitters. Clostridial neurotoxins, which proteolyze these polypeptides, are potent inhibitors of neurotransmission. The cytoplasmic domains of the three membrane proteins join into a tight SDS-resistant complex (Hayashi et al., 1994). Here, we show that this reconstituted complex, as well as heterodimers composed of syntaxin and SNAP-25, can be disassembled by the concerted action of the N-ethylmaleimide-sensitive factor, NSF, and the soluble NSF attachment protein, alpha-SNAP. alpha-SNAP binds to predicted alpha-helical coiled-coil regions of syntaxin and SNAP-25, shown previously to be engaged in their direct interaction. Synaptobrevin, although incapable of binding alpha-SNAP individually, induced a third alpha-SNAP binding site when associated with syntaxin and SNAP-25 into heterotrimers. NSF released prebound alpha-SNAP from full-length syntaxin but not from a syntaxin derivative truncated at the N-terminus. Disassembly of complexes containing this syntaxin mutant was impaired, indicating a critical role for the N-terminal domain in the alpha-SNAP/NSF-mediated dissociation process. Complexes containing C-terminally deleted SNAP-25 derivatives, as generated by botulinal toxins type A and E, were dissociated more efficiently. In contrast, the N-terminal fragment generated from synaptobrevin by botulinal toxin type F produced an SDS-sensitive complex that was poorly dissociated. Images PMID:7774590

  14. Plastics disassembly versus bulk recycling: engineering design for end-of-life electronics resource recovery.

    PubMed

    Rios, Pedro; Stuart, Julie Ann; Grant, Ed

    2003-12-01

    Annual plastic flows through the business and consumer electronics manufacturing supply chain include nearly 3 billion lb of high-value engineering plastics derived from petroleum. The recovery of resource value from this stream presents critical challenges in areas of materials identification and recycling process design that demand new green engineering technologies applied together with life cycle assessment and ecological supply chain analysis to create viable plastics-to-plastics supply cycles. The sustainable recovery of potentially high-value engineering plastics streams requires that recyclers either avoid mixing plastic parts or purify later by separating smaller plastic pieces created in volume reduction (shredding) steps. Identification and separation constitute significant barriers in the plastics-to-plastics recycling value proposition. In the present work, we develop a model that accepts randomly arriving electronic products to study scenarios by which a recycler might identify and separate high-value engineering plastics as well as metals. Using discrete eventsimulation,we compare current mixed plastics recovery with spectrochemical plastic resin identification and subsequent sorting. Our results show that limited disassembly with whole-part identification can produce substantial yields in separated streams of recovered engineering thermoplastics. We find that disassembly with identification does not constitute a bottleneck, but rather, with relatively few workers, can be configured to pull the process and thus decrease maximum staging space requirements.

  15. Synthesis of Zeolites Using the ADOR (Assembly-Disassembly-Organization-Reassembly) Route

    PubMed Central

    Wheatley, Paul S.; Čejka, Jiří; Morris, Russell E.

    2016-01-01

    Zeolites are an important class of materials that have wide ranging applications such as heterogeneous catalysts and adsorbents which are dependent on their framework topology. For new applications or improvements to existing ones, new zeolites with novel pore systems are desirable. We demonstrate a method for the synthesis of novel zeolites using the ADOR route. ADOR is an acronym for Assembly, Disassembly, Organization and Reassembly. This synthetic route takes advantage of the assembly of a relatively poorly stable that which can be selectively disassembled into a layered material. The resulting layered intermediate can then be organized in different manners by careful chemical manipulation and then reassembled into zeolites with new topologies. By carefully controlling the organization step of the synthetic pathway, new zeolites with never before seen topologies are capable of being synthesized. The structures of these new zeolites are confirmed using powder X-ray diffraction and further characterized by nitrogen adsorption and scanning electron microscopy. This new synthetic pathway for zeolites demonstrates its capability to produce novel frameworks that have never been prepared by traditional zeolite synthesis techniques. PMID:27078165

  16. Distinctive PSA-NCAM and NCAM hallmarks in glutamate-induced dendritic atrophy and synaptic disassembly.

    PubMed

    Podestá, María Fernanda; Yam, Patricia; Codagnone, Martín Gabriel; Uccelli, Nonthué Alejandra; Colman, David; Reinés, Analía

    2014-01-01

    Dendritic and synapse remodeling are forms of structural plasticity that play a critical role in normal hippocampal function. Neural cell adhesion molecule (NCAM) and its polysialylated form (PSA-NCAM) participate in neurite outgrowth and synapse formation and plasticity. However, it remains unclear whether they contribute to dendritic retraction and synaptic disassembly. Cultured hippocampal neurons exposed to glutamate (5 µM) showed a reduced MAP-2 (+) area in the absence of neuronal death 24 h after the insult. Concomitantly, synapse loss, revealed by decreased synaptophysin and post-synaptic density-95 cluster number and area, together with changes in NCAM and PSA-NCAM levels were found. Dendritic atrophy and PSA-NCAM reduction proved NMDA-receptor dependent. Live-imaging experiments evidenced dendritic atrophy 4 h after the insult; this effect was preceded by smaller NCAM clusters (1 h) and decreased surface and total PSA-NCAM levels (3 h). Simultaneously, total NCAM cluster number and area remained unchanged. The subsequent synapse disassembly (6 h) was accompanied by reductions in total NCAM cluster number and area. A PSA mimetic peptide prevented both the dendritic atrophy and the subsequent synaptic changes (6 h) but had no effect on the earliest synaptic remodeling (3 h). Thus, NCAM-synaptic reorganization and PSA-NCAM level decrease precede glutamate-induced dendritic atrophy, whereas the NCAM level reduction is a delayed event related to synapse loss. Consequently, distinctive stages in PSA-NCAM/NCAM balance seem to accompany glutamate-induced dendritic atrophy and synapse loss.

  17. PDK1 regulates focal adhesion disassembly by modulating endocytosis of αvβ3 integrin.

    PubMed

    di Blasio, Laura; Gagliardi, Paolo Armando; Puliafito, Alberto; Sessa, Roberto; Seano, Giorgio; Bussolino, Federico; Primo, Luca

    2015-03-01

    Non-amoeboid cell migration is characterised by dynamic competition among multiple protrusions to establish new adhesion sites at the cell's leading edge. However, the mechanisms that regulate the decision to disassemble or to grow nascent adhesions are not fully understood. Here we show that, in endothelial cells, 3-phosphoinositide-dependent protein kinase 1 (PDK1) promotes focal adhesion (FA) turnover by controlling endocytosis of integrin αvβ3 in a PI3K-dependent manner. We demonstrate that PDK1 binds and phosphorylates integrin αvβ3. Downregulation of PDK1 increases FA size and slows down their disassembly. This process requires both PDK1 kinase activity and PI3K activation but does not involve Akt. Moreover, PDK1 silencing stabilises FA in membrane protrusions decreasing migration of endothelial cells on vitronectin. These results indicate that modulation of integrin endocytosis by PDK1 hampers endothelial cell adhesion and migration on extracellular matrix, thus unveiling a novel role for this kinase.

  18. The cellular prion protein traps Alzheimer's Aβ in an oligomeric form and disassembles amyloid fibers

    PubMed Central

    Younan, Nadine D.; Sarell, Claire J.; Davies, Paul; Brown, David R.; Viles, John H.

    2013-01-01

    There is now strong evidence to show that the presence of the cellular prion protein (PrPC) mediates amyloid-β (Aβ) neurotoxicity in Alzheimer's disease (AD). Here, we probe the molecular details of the interaction between PrPC and Aβ and discover that substoichiometric amounts of PrPC, as little as 1/20, relative to Aβ will strongly inhibit amyloid fibril formation. This effect is specific to the unstructured N-terminal domain of PrPC. Electron microscopy indicates PrPC is able to trap Aβ in an oligomeric form. Unlike fibers, this oligomeric Aβ contains antiparallel β sheet and binds to a oligomer specific conformational antibody. Our NMR studies show that a specific region of PrPC, notably residues 95–113, binds to Aβ oligomers, but only once Aβ misfolds. The ability of PrPC to trap and concentrate Aβ in an oligomeric form and disassemble mature fibers suggests a mechanism by which PrPC might confer Aβ toxicity in AD, as oligomers are thought to be the toxic form of Aβ. Identification of a specific recognition site on PrPC that traps Aβ in an oligomeric form is potentially a therapeutic target for the treatment of Alzheimer's disease.—Younan, N. D., Sarell, C. J., Davies, P., Brown, D. R., Viles, J. H. The cellular prion protein traps Alzheimer's Aβ in an oligomeric form and disassembles amyloid fibers. PMID:23335053

  19. Extracellular Inhibitors, Repellents, and Semaphorin/Plexin/MICAL-mediated Actin Filament Disassembly

    PubMed Central

    Hung, Ruei-Jiun; Terman, Jonathan R.

    2011-01-01

    Multiple extracellular signals have been identified that regulate actin dynamics within motile cells, but how these instructive cues present on the cell surface exert their precise effects on the internal actin cytoskeleton is still poorly understood. One particularly interesting class of these cues is a group of extracellular proteins that negatively alter the movement of cells and their processes. Over the years, these types of events have been described using a variety of terms and herein we provide an overview of inhibitory/repulsive cellular phenomena and highlight the largest known protein family of repulsive extracellular cues, the Semaphorins. Specifically, the Semaphorins (Semas) utilize Plexin cell-surface receptors to dramatically collapse the actin cytoskeleton and we summarize what is known of the direct molecular and biochemical mechanisms of Sema-triggered actin filament (F-actin) disassembly. We also discuss new observations from our lab that reveal that the multi-domain oxidoreductase (Redox) enzyme MICAL, an important mediator of Sema/Plexin repulsion, is a novel F-actin disassembly factor. Our results indicate that MICAL triggers Sema/Plexin-mediated reorganization of the F-actin cytoskeleton and suggest a role for specific Redox signaling events in regulating actin dynamics. PMID:21800438

  20. Kinetics of Surface-Driven Self-Assembly and Fatigue-Induced Disassembly of a Virus-Based Nanocoating.

    PubMed

    Valbuena, Alejandro; Mateu, Mauricio G

    2017-02-28

    Self-assembling protein layers provide a "bottom-up" approach for precisely organizing functional elements at the nanoscale over a large solid surface area. The design of protein sheets with architecture and physical properties suitable for nanotechnological applications may be greatly facilitated by a thorough understanding of the principles that underlie their self-assembly and disassembly. In a previous study, the hexagonal lattice formed by the capsid protein (CA) of human immunodeficiency virus (HIV) was self-assembled as a monomolecular layer directly onto a solid substrate, and its mechanical properties and dynamics at equilibrium were analyzed by atomic force microscopy. Here, we use atomic force microscopy to analyze the kinetics of self-assembly of the planar CA lattice on a substrate and of its disassembly, either spontaneous or induced by materials fatigue. Both self-assembly and disassembly of the CA layer are cooperative reactions that proceed until a phase equilibrium is reached. Self-assembly requires a critical protein concentration and is initiated by formation of nucleation points on the substrate, followed by lattice growth and eventual merging of CA patches into a continuous monolayer. Disassembly of the CA layer showed hysteresis and appears to proceed only after large enough defects (nucleation points) are formed in the lattice, whose number is largely increased by inducing materials fatigue that depends on mechanical load and its frequency. Implications of the kinetic results obtained for a better understanding of self-assembly and disassembly of the HIV capsid and protein-based two-dimensional nanomaterials and the design of anti-HIV drugs targeting (dis)assembly and biocompatible nanocoatings are discussed.

  1. An analysis of thermionic space nuclear reactor power system: I. Effect of disassembling radial reflector, following a reactivity initiated accident

    SciTech Connect

    El-Genk, M.S.; Paramonov, D. )

    1993-01-10

    An analysis is performed to determine the effect of disassembling the radial reflector of the TOPAZ-II reactor, following a hypothetical severe Reactivity Initiated Accident (RIA). Such an RIA is assumed to occur during the system start-up in orbit due to a malfunction of the drive mechanism of the control drums, causing the drums to rotate the full 180[degree] outward at their maximum speed of 1.4[degree]/s. Results indicate that disassembling only three of twelve radial reflector panels would successfully shutdown the reactor, with little overheating of the fuel and the moderator.

  2. 29 CFR Appendix B to Subpart Cc of... - Assembly/Disassembly: Sample Procedures for Minimizing the Risk of Unintended Dangerous Boom...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 8 2013-07-01 2013-07-01 false Assembly/Disassembly: Sample Procedures for Minimizing the Risk of Unintended Dangerous Boom Movement B Appendix B to Subpart CC of Part 1926 Labor Regulations..., App. B Appendix B to Subpart CC of Part 1926—Assembly/Disassembly: Sample Procedures for...

  3. 29 CFR Appendix B to Subpart Cc of... - Assembly/Disassembly: Sample Procedures for Minimizing the Risk of Unintended Dangerous Boom...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 8 2012-07-01 2012-07-01 false Assembly/Disassembly: Sample Procedures for Minimizing the Risk of Unintended Dangerous Boom Movement B Appendix B to Subpart CC of Part 1926 Labor Regulations..., App. B Appendix B to Subpart CC of Part 1926—Assembly/Disassembly: Sample Procedures for...

  4. Supramolecular disassembly of facially amphiphilic dendrimer assemblies in response to physical, chemical, and biological stimuli.

    PubMed

    Raghupathi, Krishna R; Guo, Jing; Munkhbat, Oyuntuya; Rangadurai, Poornima; Thayumanavan, S

    2014-07-15

    CONSPECTUS: Supramolecular assemblies formed from spontaneous self-assembly of amphiphilic macromolecules are explored as biomimetic architectures and for applications in areas such as sensing, drug delivery, and diagnostics. Macromolecular assemblies are usually preferred, compared with their simpler small molecule counterparts, due to their low critical aggregate concentrations (CAC) and high thermodynamic stability. This Account focuses on the structural and functional aspects of assemblies formed from dendrimers, specifically facially amphiphilic dendrons that form micelle or inverse micelle type supramolecular assemblies depending on the nature of the solvent medium. The micelle type assemblies formed from facially amphiphilic dendrons sequester hydrophobic guest molecules in their interiors. The stability of these assemblies is dependent on the relative compatibility of the hydrophilic and hydrophobic functionalities with water, often referred to as hydrophilic-lipophilic balance (HLB). Disruption of the HLB, using an external stimulus, could lead to disassembly of the aggregates, which can then be utilized to cause an actuation event, such as guest molecule release. Studying these possibilities has led to (i) a robust and general strategy for stimulus-induced disassembly and molecular release and (ii) the introduction of a new approach to protein-responsive supramolecular disassembly. The latter strategy provides a particularly novel avenue for impacting biomedical applications. Most of the stimuli-sensitive supramolecular assemblies have been designed to be responsive to factors such pH, temperature, and redox conditions. The reason for this interest stems from the fact that certain disease microenvironments have aberrations in these factors. However, these variations are the secondary imbalances in biology. Imbalances in protein activity are the primary reasons for most, if not all, human pathology. There have been no robust strategies in stimulus

  5. A Rab1 mutant affecting guanine nucleotide exchange promotes disassembly of the Golgi apparatus

    PubMed Central

    1994-01-01

    The Golgi apparatus is a dynamic organelle whose structure is sensitive to vesicular traffic and to cell cycle control. We have examined the potential role for rab1a, a GTPase previously associated with ER to Golgi and intra-Golgi transport, in the formation and maintenance of Golgi structure. Bacterially expressed, recombinant rab1a protein was microinjected into rat embryonic fibroblasts, followed by analysis of Golgi morphology by fluorescence and electron microscopy. Three recombinant proteins were tested: wild-type rab, mutant rab1a(S25N), a constitutively GDP-bound form (Nuoffer, C., H. W. Davidson, J. Matteson, J. Meinkoth, and W. E. Balch, 1994. J. Cell Biol. 125: 225- 237), and mutant rab1a(N124I) defective in guanine nucleotide binding. Microinjection of wild-type rab1a protein or a variety of negative controls (injection buffer alone or activated ras protein) did not affect the appearance of the Golgi, as visualized by immunofluorescence of alpha-mannosidase II (Man II), used as a Golgi marker. In contrast, microinjection of the mutant forms promoted the disassembly of the Golgi stacks into dispersed vesicular structures visualized by immunofluorescence. When S25N-injected cells were analyzed by EM after immunoperoxidase labeling, Man II was found in isolated ministacks and large vesicular elements that were often surrounded by numerous smaller unlabeled vesicles resembling carrier vesicles. Golgi disassembly caused by rab1a mutants differs from BFA-induced disruption, since beta- COP remains membrane associated, and Man II does not redistribute to the ER. BFA can still cause these residual Golgi elements to fuse and disperse, albeit at a slower rate. Moreover, BFA recovery is incomplete in the presence of rab1 mutants or GTP gamma S. We conclude that GTP exchange and hydrolysis by GTPases, specifically rab1a, are required to form and maintain normal Golgi stacks. The similarity of Golgi disassembly seen with rab1a mutants to that occurring during

  6. Ufd1-Npl4 Recruit Cdc48 for Disassembly of Ubiquitylated CMG Helicase at the End of Chromosome Replication.

    PubMed

    Maric, Marija; Mukherjee, Progya; Tatham, Michael H; Hay, Ronald; Labib, Karim

    2017-03-28

    Disassembly of the Cdc45-MCM-GINS (CMG) DNA helicase is the key regulated step during DNA replication termination in eukaryotes, involving ubiquitylation of the Mcm7 helicase subunit, leading to a disassembly process that requires the Cdc48 "segregase". Here, we employ a screen to identify partners of budding yeast Cdc48 that are important for disassembly of ubiquitylated CMG helicase at the end of chromosome replication. We demonstrate that the ubiquitin-binding Ufd1-Npl4 complex recruits Cdc48 to ubiquitylated CMG. Ubiquitylation of CMG in yeast cell extracts is dependent upon lysine 29 of Mcm7, which is the only detectable site of ubiquitylation both in vitro and in vivo (though in vivo other sites can be modified when K29 is mutated). Mutation of K29 abrogates in vitro recruitment of Ufd1-Npl4-Cdc48 to the CMG helicase, supporting a model whereby Ufd1-Npl4 recruits Cdc48 to ubiquitylated CMG at the end of chromosome replication, thereby driving the disassembly reaction.

  7. Chromatin remodeller Fun30Fft3 induces nucleosome disassembly to facilitate RNA polymerase II elongation

    PubMed Central

    Lee, Junwoo; Shik Choi, Eun; David Seo, Hogyu; Kang, Keunsoo; Gilmore, Joshua M.; Florens, Laurence; Washburn, Michael P.; Choe, Joonho; Workman, Jerry L.; Lee, Daeyoup

    2017-01-01

    Previous studies have revealed that nucleosomes impede elongation of RNA polymerase II (RNAPII). Recent observations suggest a role for ATP-dependent chromatin remodellers in modulating this process, but direct in vivo evidence for this is unknown. Here using fission yeast, we identify Fun30Fft3 as a chromatin remodeller, which localizes at transcribing regions to promote RNAPII transcription. Fun30Fft3 associates with RNAPII and collaborates with the histone chaperone, FACT, which facilitates RNAPII elongation through chromatin, to induce nucleosome disassembly at transcribing regions during RNAPII transcription. Mutants, resulting in reduced nucleosome-barrier, such as deletion mutants of histones H3/H4 themselves and the genes encoding components of histone deacetylase Clr6 complex II suppress the defects in growth and RNAPII occupancy of cells lacking Fun30Fft3. These data suggest that RNAPII utilizes the chromatin remodeller, Fun30Fft3, to overcome the nucleosome barrier to transcription elongation. PMID:28218250

  8. Regulation of ceramide channel formation and disassembly: Insights on the initiation of apoptosis

    PubMed Central

    Abou-Ghali, Majdouline; Stiban, Johnny

    2015-01-01

    Sphingolipid research has surged in the past two decades and has produced a wide variety of evidence supporting the role of this class of molecules in mediating cellular growth, differentiation, senescence, and apoptosis. Ceramides are a subgroup of sphingolipids (SLs) that are directly involved in the process of initiation of apoptosis. We, and others, have recently shown that ceramides are capable of the formation of protein-permeable channels in mitochondrial outer membranes under physiological conditions. These pores are indeed good candidates for the pathway of release of pro-apoptotic proteins from the mitochondrial intermembrane space (IMS) into the cytosol to initiate intrinsic apoptosis. Here, we review recent findings on the regulation of ceramide channel formation and disassembly, highlighting possible implications on the initiation of the intrinsic apoptotic pathway. PMID:26587005

  9. Disassembly time of deuterium-cluster-fusion plasma irradiated by an intense laser pulse

    SciTech Connect

    Bang, W.

    2015-07-02

    Energetic deuterium ions from large deuterium clusters (>10 nm diameter) irradiated by an intense laser pulse (>10¹⁶ W/cm²) produce DD fusion neutrons for a time interval determined by the geometry of the resulting fusion plasma. We show an analytical solution of this time interval, the plasma disassembly time, for deuterium plasmas that are cylindrical in shape. Assuming a symmetrically expanding deuterium plasma, we calculate the expected fusion neutron yield and compare with an independent calculation of the yield using the concept of a finite confinement time at a fixed plasma density. The calculated neutron yields agree quantitatively with the available experimental data. Our one-dimensional simulations indicate that one could expect a tenfold increase in total neutron yield by magnetically confining a 10 - keV deuterium fusion plasma for 10 ns.

  10. Microtubule-depolymerizing kinesins in the regulation of assembly, disassembly, and length of cilia and flagella.

    PubMed

    Hu, Zhangfeng; Liang, Yinwen; Meng, Dan; Wang, Liang; Pan, Junmin

    2015-01-01

    Defects in ciliary assembly, maintenance, and signaling are associated with various human diseases and developmental disorders, termed ciliopathies. Eukaryotic flagella and cilia (interchangeable terms) are microtubule-based organelles. Thus, microtubule dynamics and microtubule-dependent transport are predicted to affect the structural integrity and functionality of cilia profoundly. Kinesin-2 is well known for its role in intraflagellar transport to transport ciliary precursors and signaling molecules. Recently, microtubule-depolymerizing kinesins found in kinesin-8, -13, and -14A families have emerged as regulators of cilia. We first discuss ciliary kinesins identified in the flagellar or ciliary proteome, and then focus on the function and regulation of microtubule-depolymerizing kinesins. Lastly, we review the recent advances of microtubule-depolymerizing kinesins in controlling ciliary assembly, disassembly, and length.

  11. Neuroprotective Effects Against POCD by Photobiomodulation: Evidence from Assembly/Disassembly of the Cytoskeleton

    PubMed Central

    Liebert, Ann D.; Chow, Roberta T.; Bicknell, Brian T.; Varigos, Euahna

    2016-01-01

    Postoperative cognitive dysfunction (POCD) is a decline in memory following anaesthesia and surgery in elderly patients. While often reversible, it consumes medical resources, compromises patient well-being, and possibly accelerates progression into Alzheimer’s disease. Anesthetics have been implicated in POCD, as has neuroinflammation, as indicated by cytokine inflammatory markers. Photobiomodulation (PBM) is an effective treatment for a number of conditions, including inflammation. PBM also has a direct effect on microtubule disassembly in neurons with the formation of small, reversible varicosities, which cause neural blockade and alleviation of pain symptoms. This mimics endogenously formed varicosities that are neuroprotective against damage, toxins, and the formation of larger, destructive varicosities and focal swellings. It is proposed that PBM may be effective as a preconditioning treatment against POCD; similar to the PBM treatment, protective and abscopal effects that have been demonstrated in experimental models of macular degeneration, neurological, and cardiac conditions. PMID:26848276

  12. Disassembly time of deuterium-cluster-fusion plasma irradiated by an intense laser pulse

    DOE PAGES

    Bang, W.

    2015-07-02

    Energetic deuterium ions from large deuterium clusters (>10 nm diameter) irradiated by an intense laser pulse (>10¹⁶ W/cm²) produce DD fusion neutrons for a time interval determined by the geometry of the resulting fusion plasma. We show an analytical solution of this time interval, the plasma disassembly time, for deuterium plasmas that are cylindrical in shape. Assuming a symmetrically expanding deuterium plasma, we calculate the expected fusion neutron yield and compare with an independent calculation of the yield using the concept of a finite confinement time at a fixed plasma density. The calculated neutron yields agree quantitatively with the availablemore » experimental data. Our one-dimensional simulations indicate that one could expect a tenfold increase in total neutron yield by magnetically confining a 10 - keV deuterium fusion plasma for 10 ns.« less

  13. Remote disassembly of the absorber open-test assembly at the FFTF/IEM cell

    SciTech Connect

    Ramsey, E.B.

    1990-01-01

    The Fast Flux Test Facility (FFTF) interim examination and maintenance (IEM) cell is used for the remote disassembly of irradiated fuel and material experiments. The absorber open-test assembly (AOTA) is a 12-m (40-ft)-long instrumented absorber (control-rod-material) test assembly. Its primary purpose is to characterize the FFTF control-rod-material reaction rate during reactor operation. Instrumentation allowed temperature and pressure measurements at various locations in several absorber pins during reactor operation. After residing several months in the reactor, the assembly was transferred to the IEM cell by the closed-loop ex-vessel machine (CLEM) for separation of the irradiated portion of the experiment from the instrument stalk. After separation, the 3.6-m (12-ft)-long assembly was processed through the sodium removal system and shipped off-site for examination. This success allowed the timely completion of a major task on the FFTF operations schedule.

  14. QIL1 mutation causes MICOS disassembly and early onset fatal mitochondrial encephalopathy with liver disease.

    PubMed

    Guarani, Virginia; Jardel, Claude; Chrétien, Dominique; Lombès, Anne; Bénit, Paule; Labasse, Clémence; Lacène, Emmanuelle; Bourillon, Agnès; Imbard, Apolline; Benoist, Jean-François; Dorboz, Imen; Gilleron, Mylène; Goetzman, Eric S; Gaignard, Pauline; Slama, Abdelhamid; Elmaleh-Bergès, Monique; Romero, Norma B; Rustin, Pierre; Ogier de Baulny, Hélène; Paulo, Joao A; Harper, J Wade; Schiff, Manuel

    2016-09-13

    Previously, we identified QIL1 as a subunit of mitochondrial contact site (MICOS) complex and demonstrated a role for QIL1 in MICOS assembly, mitochondrial respiration, and cristae formation critical for mitochondrial architecture (Guarani et al., 2015). Here, we identify QIL1 null alleles in two siblings displaying multiple clinical symptoms of early-onset fatal mitochondrial encephalopathy with liver disease, including defects in respiratory chain function in patient muscle. QIL1 absence in patients' fibroblasts was associated with MICOS disassembly, abnormal cristae, mild cytochrome c oxidase defect, and sensitivity to glucose withdrawal. QIL1 expression rescued cristae defects, and promoted re-accumulation of MICOS subunits to facilitate MICOS assembly. MICOS assembly and cristae morphology were not efficiently rescued by over-expression of other MICOS subunits in patient fibroblasts. Taken together, these data provide the first evidence of altered MICOS assembly linked with a human mitochondrial disease and confirm a central role for QIL1 in stable MICOS complex formation.

  15. Multi-criteria decision-making for optimization of product disassembly under multiple situations.

    PubMed

    Hula, Aaron; Jalali, Kiumars; Hamza, Karim; Skerlos, Steven J; Saitou, Kazuhiro

    2003-12-01

    With growing interest in recovering materials and subassemblies within consumer products at the end of their useful life, there has been an increasing interest in developing decision-making methodologies that determine how to maximize the environmental benefits of end-of-life (EOL) processing while minimizing costs under variable EOL situations. This paper describes a methodology to analyze how product designs and situational variables impact the Pareto set of optimal EOL strategies with the greatest environmental benefit for a given economic cost or profit. Since the determination of this Pareto set via enumeration of all disassembly sequences and EOL fates is prohibitively time-consuming even for relatively simple products, multi-objective genetic algorithms (GA) are utilized to rapidly approximate the Pareto set of optimal EOL trade-offs between cost and environmentally conscious actions. Such rapid calculations of the Pareto set are critical to better understand the influence of situational variables on how disassembly and recycling decisions change under different EOL scenarios (e.g., undervariable regulatory, infrastructure, or market situations). To illustrate the methodology, a case study involving the EOL treatment of a coffee maker is described. Impacts of situational variables on trade-offs between recovered energy and cost in Aachen, Germany, and in Ann Arbor, MI, are elucidated, and a means of presenting the results in the form of a multi-situational EOL strategy graph is described. The impact of the European Union Directive regarding Waste Electric and Electronic Equipment (WEEE) on EOL trade-offs between energy recovery and cost was also considered for both locations.

  16. Permo-Triassic anatexis, continental rifting and the disassembly of western Pangaea

    NASA Astrophysics Data System (ADS)

    Cochrane, Ryan; Spikings, Richard; Gerdes, Axel; Ulianov, Alexey; Mora, Andres; Villagómez, Diego; Putlitz, Benita; Chiaradia, Massimo

    2014-03-01

    Crustal anatectites are frequently observed along ocean-continent active margins, although their origins are disputed with interpretations varying between rift-related and collisional. We report geochemical, isotopic and geochronological data that define an ~ 1500 km long belt of S-type meta-granites along the Andes of Colombia and Ecuador, which formed during 275-223 Ma. These are accompanied by amphibolitized tholeiitic basaltic dykes that yield concordant zircon U-Pb dates ranging between 240 and 223 Ma. A model is presented which places these rocks within a compressive Permian arc setting that existed during the amalgamation of westernmost Pangaea. Anatexis and mafic intrusion during 240-223 Ma are interpreted to have occurred during continental rifting, which culminated in the formation of oceanic crust and initiated the break-up of western Pangaea. Compression during 275-240 Ma generated small volumes of crustal melting. Rifting during 240-225 Ma was characterized by basaltic underplating, the intrusion of tholeiitic basalts and a peak in crustal melting. Tholeiitic intrusions during 225-216 Ma isotopically resemble depleted mantle and yield no evidence for contamination by continental crust, and we assign this period to the onset of continental drift. Dissected ophiolitic sequences in northern Colombia yield zircon U-Pb dates of 216 Ma. The Permo-Triassic margin of Ecuador and Colombia exhibits close temporal, faunal and geochemical similarities with various crustal blocks that form the basement to parts of Mexico, and thus these may represent the relict conjugate margin to NW Gondwana. The magmatic record of the early disassembly of Pangaea spans ~ 20 Ma (240-216 Ma), and the duration of rifting and rift-drift transition is similar to that documented in Cretaceous-Tertiary rift settings such as the West Iberia-Newfoundland conjugate margins, and the Taupo-Lau-Havre System, where rifting and continental disassembly also occurred over periods lasting ~ 20 Ma.

  17. RADIOLOGICAL SURVEY STATION DEVELOPMENT FOR THE PIT DISASSEMBLY AND CONVERSION PROJECT

    SciTech Connect

    Dalmaso, M.; Gibbs, K.; Gregory, D.

    2011-05-22

    The Savannah River National Laboratory (SRNL) has developed prototype equipment to demonstrate remote surveying of Inner and Outer DOE Standard 3013 containers for fixed and transferable contamination in accordance with DOE Standard 3013 and 10 CFR 835 Appendix B. When fully developed the equipment will be part of a larger suite of equipment used to package material in accordance with DOE Standard 3013 at the Pit Disassembly and Conversion Project slated for installation at the Savannah River Site. The prototype system consists of a small six-axis industrial robot with an end effector consisting of a force sensor, vacuum gripper and a three fingered pneumatic gripper. The work cell also contains two alpha survey instruments, swipes, swipe dispenser, and other ancillary equipment. An external controller interfaces with the robot controller, survey instruments and other ancillary equipment to control the overall process. SRNL is developing automated equipment for the Pit Disassembly and Conversion (PDC) Project that is slated for the Savannah River Site (SRS). The equipment being developed is automated packaging equipment for packaging plutonium bearing materials in accordance with DOE-STD-3013-2004. The subject of this paper is the development of a prototype Radiological Survey Station (RSS). Other automated equipment being developed for the PDC includes the Bagless transfer System, Outer Can Welder, Gantry Robot System (GRS) and Leak Test Station. The purpose of the RSS is to perform a frisk and swipe of the DOE Standard 3013 Container (either inner can or outer can) to check for fixed and transferable contamination. This is required to verify that the contamination levels are within the limits specified in DOE-STD-3013-2004 and 10 CFR 835, Appendix D. The surface contamination limit for the 3013 Outer Can (OC) is 500 dpm/100 cm2 (total) and 20 dpm/100 cm2 (transferable). This paper will concentrate on the RSS developments for the 3013 OC but the system for the

  18. Distinctive PSA-NCAM and NCAM Hallmarks in Glutamate-Induced Dendritic Atrophy and Synaptic Disassembly

    PubMed Central

    Podestá, María Fernanda; Yam, Patricia; Codagnone, Martín Gabriel; Uccelli, Nonthué Alejandra; Colman, David; Reinés, Analía

    2014-01-01

    Dendritic and synapse remodeling are forms of structural plasticity that play a critical role in normal hippocampal function. Neural cell adhesion molecule (NCAM) and its polysialylated form (PSA-NCAM) participate in neurite outgrowth and synapse formation and plasticity. However, it remains unclear whether they contribute to dendritic retraction and synaptic disassembly. Cultured hippocampal neurons exposed to glutamate (5 µM) showed a reduced MAP-2 (+) area in the absence of neuronal death 24 h after the insult. Concomitantly, synapse loss, revealed by decreased synaptophysin and post-synaptic density-95 cluster number and area, together with changes in NCAM and PSA-NCAM levels were found. Dendritic atrophy and PSA-NCAM reduction proved NMDA-receptor dependent. Live-imaging experiments evidenced dendritic atrophy 4 h after the insult; this effect was preceded by smaller NCAM clusters (1 h) and decreased surface and total PSA-NCAM levels (3 h). Simultaneously, total NCAM cluster number and area remained unchanged. The subsequent synapse disassembly (6 h) was accompanied by reductions in total NCAM cluster number and area. A PSA mimetic peptide prevented both the dendritic atrophy and the subsequent synaptic changes (6 h) but had no effect on the earliest synaptic remodeling (3 h). Thus, NCAM-synaptic reorganization and PSA-NCAM level decrease precede glutamate-induced dendritic atrophy, whereas the NCAM level reduction is a delayed event related to synapse loss. Consequently, distinctive stages in PSA-NCAM/NCAM balance seem to accompany glutamate-induced dendritic atrophy and synapse loss. PMID:25279838

  19. Assembly and disassembly of the Golgi complex: two processes arranged in a cis-trans direction

    PubMed Central

    1992-01-01

    We have studied the disassembly and assembly of two morphologically and functionally distinct parts of the Golgi complex, the cis/middle and trans cisterna/trans network compartments. For this purpose we have followed the redistribution of three cis/middle- (GMPc-1, GMPc-2, MG 160) and two trans- (GMPt-1 and GMPt-2) Golgi membrane proteins during and after treatment of normal rat kidney (NRK) cells with brefeldin A (BFA). BFA induced complete disassembly of the cis/middle- and trans- Golgi complex and translocation of GMPc and GMPt to the ER. Cells treated for short times (3 min) with BFA showed extensive disorganization of both cis/middle- and trans-Golgi complexes. However, complete disorganization of the trans part required much longer incubations with the drug. Upon removal of BFA the Golgi complex was reassembled by a process consisting of three steps: (a) exist of cis/middle proteins from the ER and their accumulation into vesicular structures scattered throughout the cytoplasm; (b) gradual relocation and accumulation of the trans proteins in the vesicles containing the cis/middle proteins; and (c) assembly of the cisternae, and reconstruction of the Golgi complex within an area located in the vicinity of the centrosome from which the ER was excluded. Reconstruction of the cis/middle-Golgi complex occurred under temperature conditions inhibitory of the reorganization of the trans- Golgi complex, and was dependent on microtubules. Reconstruction of the trans-Golgi complex, disrupted with nocodazole after selective fusion of the cis/middle-Golgi complex with the ER, occurred after the release of cis/middle-Golgi proteins from the ER and the assembly of the cis/middle cisternae. PMID:1730750

  20. The Prolyl Isomerase Pin1 Promotes the Herpesvirus-Induced Phosphorylation-Dependent Disassembly of the Nuclear Lamina Required for Nucleocytoplasmic Egress

    PubMed Central

    Milbradt, Jens; Hutterer, Corina; Bahsi, Hanife; Wagner, Sabrina; Sonntag, Eric; Kaufer, Benedikt B.; Mori, Yasuko; Sticht, Heinrich; Fossen, Torgils; Marschall, Manfred

    2016-01-01

    The nuclear lamina lines the inner nuclear membrane providing a structural framework for the nucleus. Cellular processes, such as nuclear envelope breakdown during mitosis or nuclear export of large ribonucleoprotein complexes, are functionally linked to the disassembly of the nuclear lamina. In general, lamina disassembly is mediated by phosphorylation, but the precise molecular mechanism is still not completely understood. Recently, we suggested a novel mechanism for lamina disassembly during the nuclear egress of herpesviral capsids which involves the cellular isomerase Pin1. In this study, we focused on mechanistic details of herpesviral nuclear replication to demonstrate the general importance of Pin1 for lamina disassembly. In particular, Ser22-specific lamin phosphorylation consistently generates a Pin1-binding motif in cells infected with human and animal alpha-, beta-, and gammaherpesviruses. Using nuclear magnetic resonance spectroscopy, we showed that binding of Pin1 to a synthetic lamin peptide induces its cis/trans isomerization in vitro. A detailed bioinformatic evaluation strongly suggests that this structural conversion induces large-scale secondary structural changes in the lamin N-terminus. Thus, we concluded that a Pin1-induced conformational change of lamins may represent the molecular trigger responsible for lamina disassembly. Consistent with this concept, pharmacological inhibition of Pin1 activity blocked lamina disassembly in herpesvirus-infected fibroblasts and consequently impaired virus replication. In addition, a phospho-mimetic Ser22Glu lamin mutant was still able to form a regular lamina structure and overexpression of a Ser22-phosphorylating kinase did not induce lamina disassembly in Pin1 knockout cells. Intriguingly, this was observed in absence of herpesvirus infection proposing a broader importance of Pin1 for lamina constitution. Thus, our results suggest a functional model of similar events leading to disassembly of the nuclear

  1. BASINS Publications

    EPA Pesticide Factsheets

    Although BASINS has been in use for the past 10 years, there has been limited modeling guidance on its applications for complex environmental problems, such as modeling impacts of hydro modification on water quantity and quality.

  2. AGR-3/4 Irradiation Test Train Disassembly and Component Metrology First Look Report

    SciTech Connect

    Stempien, John Dennis; Rice, Francine Joyce; Harp, Jason Michael; Winston, Philip Lon

    2016-03-01

    The AGR-3/4 experiment was designed to study fission product transport within graphitic matrix material and nuclear-grade graphite. To this end, this experiment consisted of 12 capsules, each fueled with 4 compacts containing UCO TRISO particles as driver fuel and 20 UCO designed-to-fail (DTF) fuel particles in each compact. The DTF fuel was fabricated with a thin pyrocarbon layer which was intended to fail during irradiation and provide a source of fission products. These fission products could then migrate through the compact and into the surrounding concentric rings of graphitic matrix material and/or nuclear graphite. Through post-irradiation examination (PIE) of the rings (including physical sampling and gamma scanning) fission product concentration profiles within the rings can be determined. These data can be used to elucidate fission product transport parameters (e.g. diffusion coefficients within the test materials) which will be used to inform and refine models of fission product transport. After irradiation in the Advanced Test Reactor (ATR) had been completed in April 2014, the AGR-3/4 experiment was shipped to the Hot Fuel Examination Facility (HFEF) at the Materials and Fuels Complex (MFC) for inspection, disassembly, and metrology. The AGR-3/4 test train was received at MFC in two separate shipments between February and April 2015. Visual examinations of the test train exterior did not indicate dimensional distortion, and only two small discolored areas were observed at the bottom of Capsules 8 and 9. No corresponding discoloration was found on the inside of these capsules, however. Prior to disassembly, the two test train sections were subject to analysis via the Precision Gamma Scanner (PGS), which did not indicate that any gross fuel relocation had occurred. A series of specialized tools (including clamps, cutters, and drills) had been designed and fabricated in order to carry out test train disassembly and recovery of capsule components (graphite

  3. Intracellular Disassembly of Self-Quenched Nanoparticles Turns NIR Fluorescence on for Sensing Furin Activity in Cells and in Tumors.

    PubMed

    Yuan, Yue; Zhang, Jia; Cao, Qinjingwen; An, Linna; Liang, Gaolin

    2015-06-16

    There has been no report on enzyme-controlled disassembly of self-quenched NIR fluorescent nanoparticles turning fluorescence on for specific detection/imaging of the enzyme's activity in vitro and in vivo. Herein, we reported the rational design of new NIR probe 1 whose fluorescence signal was self-quenched upon reduction-controlled condensation and subsequent assembly of its nanoparticles (i.e., 1-NPs). Then disassembly of 1-NPs by furin turned the fluorescence on. Employing this enzymatic strategy, we successfully applied 1-NPs for NIR detection of furin in vitro and NIR imaging furin activity in living cells. Moreover, we also applied 1-NPs for discriminative NIR imaging of MDA-MB-468 tumors in nude mice. This NIR probe 1 might be further developed for tumor-targeted imaging in routine preclinical studies or even in patients in the future.

  4. RHGF-1/PDZ-RhoGEF and retrograde DLK-1 signaling drive neuronal remodeling on microtubule disassembly.

    PubMed

    Chen, Chun-Hao; Lee, Albert; Liao, Chien-Po; Liu, Ya-Wen; Pan, Chun-Liang

    2014-11-18

    Neurons remodel their connectivity in response to various insults, including microtubule disruption. How neurons sense microtubule disassembly and mount remodeling responses by altering genetic programs in the soma are not well defined. Here we show that in response to microtubule disassembly, the Caenorhabditis elegans PLM neuron remodels by retracting its synaptic branch and overextending the primary neurite. This remodeling required RHGF-1, a PDZ-Rho guanine nucleotide exchange factor (PDZ-RhoGEF) that was associated with and inhibited by microtubules. Independent of the myosin light chain activation, RHGF-1 acted through Rho-dependent kinase LET-502/ROCK and activated a conserved, retrograde DLK-1 MAPK (DLK-1/dual leucine zipper kinase) pathway, which triggered synaptic branch retraction and overgrowth of the PLM neurite in a dose-dependent manner. Our data represent a neuronal remodeling paradigm during development that reshapes the neural circuit by the coordinated removal of the dysfunctional synaptic branch compartment and compensatory extension of the primary neurite.

  5. Parana basin

    SciTech Connect

    Zalan, P.V.; Wolff, S.; Conceicao, J.C.J.; Vieira, I.S.; Astolfi, M.A.; Appi, V.T.; Zanotto, O.; Neto, E.V.S.; Cerqueira, J.R.

    1987-05-01

    The Parana basin is a large intracratonic basin in South America, developed entirely on continental crust and filled with sedimentary and volcanic rocks ranging in age from Silurian to Cretaceous. It occupies the southern portion of Brazil (1,100,000 km/sup 2/ or 425,000 mi/sup 2/) and the eastern half of Paraguay (100,000 km/sup 2/ or 39,000 mi/sup 2/); its extension into Argentina and Uruguay is known as the Chaco-Parana basin. Five major depositional sequences (Silurian, Devonian, Permo-Carboniferous, Triassic, Juro-Cretaceous) constitute the stratigraphic framework of the basin. The first four are predominantly siliciclastic in nature, and the fifth contains the most voluminous basaltic lava flows of the planet. Maximum thicknesses are in the order of 6000 m (19,646 ft). The sequences are separated by basin wide unconformities related in the Paleozoic to Andean orogenic events and in the Mesozoic to the continental breakup and sea floor spreading between South America and Africa. The structural framework of the Parana basin consists of a remarkable pattern of criss-crossing linear features (faults, fault zones, arches) clustered into three major groups (N45/sup 0/-65/sup 0/W, N50/sup 0/-70/sup 0/E, E-W). The northwest- and northeast-trending faults are long-lived tectonic elements inherited from the Precambrian basement whose recurrent activity throughout the Phanerozoic strongly influenced sedimentation, facies distribution, and development of structures in the basin. Thermomechanical analyses indicate three main phases of subsidence (Silurian-Devonian, late Carboniferous-Permian, Late Jurassic-Early Cretaceous) and low geothermal gradients until the beginning of the Late Jurassic Permian oil-prone source rocks attained maturation due to extra heat originated from Juro-Cretaceous igneous intrusions. The third phase of subsidence also coincided with strong tectonic reactivation and creation of a third structural trend (east-west).

  6. Formation and Assembly-Disassembly Processes of ZnO Hexagonal Pyramids Driven by Dipolar and Excluded Volume Interactions

    SciTech Connect

    Yang, Ming; Sun, Kai; Kotov, Nicholas A.

    2010-01-20

    ZnO hexagonal pyramids were obtained in hydrophilic media without any traditional stabilizers (capping agents). The absence of a thick organic shell reducing the anisotropy of nanoparticle (NP) interactions, oxide nature of the materials, and new geometry of the nanocrystals makes possible the observation of new self-organization phenomena. Several new features not present in the previous cases of NP self-organization were identified and discussed. The formation of ZnO pyramids involved recrystallization of larger amorphous NPs followed by the multistage disassembly of intermediate aggregates into individual virtually perfectly shaped nanocrystals. The evolution of NPs begins with crystallization of clustered plates within the original amorphous spherical colloids, and then agglomerated truncated pyramids are formed. These agglomerates further transform into chained pyramids, which eventually separate from each other. The crystallization and disassembly processes can be associated with the decrease of potential and anisotropy of the attractive force field around the crystallites represented in part by dipole moments. The reassembly of the pyramids can still be attained via engaging excluded volume interaction after adding similarly charged polymer. Overall, in this system, we see the first examples of (1) coupled crystallization and disassembly process; (2) induced assembly of nanoscale particles using excluded volume interactions, which were previously used only for aggregation of microscale colloids; and (3) nanoparticle assemblies with variable and experimentally verifiable relative orientation of dipoles including head-to-tail, tail-to-tail pairs, and antiparallel chains. Described assemblies of ZnO pyramids with collective behavior of individual building blocks as well as distinct and experimentally controlled stages of assembly and disassembly present a fundamentally interesting nanoparticle system with rich dynamic behavior.

  7. Formation and assembly-disassembly processes of ZnO hexagonal pyramids driven by dipolar and excluded volume interactions.

    PubMed

    Yang, Ming; Sun, Kai; Kotov, Nicholas A

    2010-02-17

    ZnO hexagonal pyramids were obtained in hydrophilic media without any traditional stabilizers (capping agents). The absence of a thick organic shell reducing the anisotropy of nanoparticle (NP) interactions, oxide nature of the materials, and new geometry of the nanocrystals makes possible the observation of new self-organization phenomena. Several new features not present in the previous cases of NP self-organization were identified and discussed. The formation of ZnO pyramids involved recrystallization of larger amorphous NPs followed by the multistage disassembly of intermediate aggregates into individual virtually perfectly shaped nanocrystals. The evolution of NPs begins with crystallization of clustered plates within the original amorphous spherical colloids, and then agglomerated truncated pyramids are formed. These agglomerates further transform into chained pyramids, which eventually separate from each other. The crystallization and disassembly processes can be associated with the decrease of potential and anisotropy of the attractive force field around the crystallites represented in part by dipole moments. The reassembly of the pyramids can still be attained via engaging excluded volume interaction after adding similarly charged polymer. Overall, in this system, we see the first examples of (1) coupled crystallization and disassembly process; (2) induced assembly of nanoscale particles using excluded volume interactions, which were previously used only for aggregation of microscale colloids; and (3) nanoparticle assemblies with variable and experimentally verifiable relative orientation of dipoles including head-to-tail, tail-to-tail pairs, and antiparallel chains. Described assemblies of ZnO pyramids with collective behavior of individual building blocks as well as distinct and experimentally controlled stages of assembly and disassembly present a fundamentally interesting nanoparticle system with rich dynamic behavior.

  8. Spent fuel disassembly hardware and other non-fuel bearing components: characterization, disposal cost estimates, and proposed repository acceptance requirements

    SciTech Connect

    Luksic, A.T.; McKee, R.W.; Daling, P.M.; Konzek, G.J.; Ludwick, J.D.; Purcell, W.L.

    1986-10-01

    There are two categories of waste considered in this report. The first is the spent fuel disassembly (SFD) hardware. This consists of the hardware remaining after the fuel pins have been removed from the fuel assembly. This includes end fittings, spacer grids, water rods (BWR) or guide tubes (PWR) as appropriate, and assorted springs, fasteners, etc. The second category is other non-fuel-bearing (NFB) components the DOE has agreed to accept for disposal, such as control rods, fuel channels, etc., under Appendix E of the standard utiltiy contract (10 CFR 961). It is estimated that there will be approximately 150 kg of SFD and NFB waste per average metric ton of uranium (MTU) of spent uranium. PWR fuel accounts for approximately two-thirds of the average spent-fuel mass but only 50 kg of the SFD and NFB waste, with most of that being spent fuel disassembly hardware. BWR fuel accounts for one-third of the average spent-fuel mass and the remaining 100 kg of the waste. The relatively large contribution of waste hardware in BWR fuel, will be non-fuel-bearing components, primarily consisting of the fuel channels. Chapters are devoted to a description of spent fuel disassembly hardware and non-fuel assembly components, characterization of activated components, disposal considerations (regulatory requirements, economic analysis, and projected annual waste quantities), and proposed acceptance requirements for spent fuel disassembly hardware and other non-fuel assembly components at a geologic repository. The economic analysis indicates that there is a large incentive for volume reduction.

  9. ARC: A compact, high-field, disassemblable fusion nuclear science facility and demonstration power plant

    NASA Astrophysics Data System (ADS)

    Sorbom, Brandon; Ball, Justin; Palmer, Timothy; Mangiarotti, Franco; Sierchio, Jennifer; Bonoli, Paul; Kasten, Cale; Sutherland, Derek; Barnard, Harold; Haakonsen, Christian; Goh, Jon; Sung, Choongki; Whyte, Dennis

    2014-10-01

    The Affordable, Robust, Compact (ARC) reactor conceptual design aims to reduce the size, cost, and complexity of a combined Fusion Nuclear Science Facility (FNSF) and demonstration fusion pilot power plant. ARC is a 270 MWe tokamak reactor with a major radius of 3.3 m, a minor radius of 1.1 m, and an on-axis magnetic field of 9.2 T. ARC has Rare Earth Barium Copper Oxide (REBCO) superconducting toroidal field coils with joints to allow disassembly, allowing for removal and replacement of the vacuum vessel as a single component. Inboard-launched current drive of 25 MW LHRF power and 13.6 MW ICRF power is used to provide a robust, steady state core plasma far from disruptive limits. ARC uses an all-liquid blanket, consisting of low pressure, slowly flowing Fluorine Lithium Beryllium (FLiBe) molten salt. The liquid blanket acts as a working fluid, coolant, and tritium breeder, and minimizes the solid material that can become activated. The large temperature range over which FLiBe is liquid permits blanket operation at 800-900 K with single phase fluid cooling and allows use of a high-efficiency Brayton cycle for electricity production in the secondary coolant loop.

  10. Instantaneous inactivation of cofilin reveals its function of F-actin disassembly in lamellipodia.

    PubMed

    Vitriol, Eric A; Wise, Ariel L; Berginski, Mathew E; Bamburg, James R; Zheng, James Q

    2013-07-01

    Cofilin is a key regulator of the actin cytoskeleton. It can sever actin filaments, accelerate filament disassembly, act as a nucleation factor, recruit or antagonize other actin regulators, and control the pool of polymerization-competent actin monomers. In cells these actions have complex functional outputs. The timing and localization of cofilin activity are carefully regulated, and thus global, long-term perturbations may not be sufficient to probe its precise function. To better understand cofilin's spatiotemporal action in cells, we implemented chromophore-assisted laser inactivation (CALI) to instantly and specifically inactivate it. In addition to globally inhibiting actin turnover, CALI of cofilin generated several profound effects on the lamellipodia, including an increase of F-actin, a rearward expansion of the actin network, and a reduction in retrograde flow speed. These results support the hypothesis that the principal role of cofilin in lamellipodia at steady state is to break down F-actin, control filament turnover, and regulate the rate of retrograde flow.

  11. D1 dopamine receptor stimulation impairs striatal proteasome activity in Parkinsonism through 26S proteasome disassembly.

    PubMed

    Barroso-Chinea, Pedro; Thiolat, Marie-Laure; Bido, Simone; Martinez, Audrey; Doudnikoff, Evelyne; Baufreton, Jérôme; Bourdenx, Mathieu; Bloch, Bertrand; Bezard, Erwan; Martin-Negrier, Marie-Laure

    2015-06-01

    Among the mechanisms underlying the development of L-dopa-induced dyskinesia (LID) in Parkinson's disease, complex alterations in dopamine signaling in D1 receptor (D1R)-expressing medium spiny striatal neurons have been unraveled such as, but not limited to, dysregulation of D1R expression, lateral diffusion, intraneuronal trafficking, subcellular localization and desensitization, leading to a pathological anchorage of D1R at the plasma membrane. Such anchorage is partly due to a decreased proteasomal activity that is specific of the L-dopa-exposed dopamine-depleted striatum, results from D1R activation and feeds-back the D1R exaggerated cell surface abundance. The precise mechanisms by which L-dopa affects striatal proteasome activity remained however unknown. We here show, in a series of in vitro ex vivo and in vivo models, that such rapid modulation of striatal proteasome activity intervenes through D1R-mediated disassembly of the 26S proteasome rather than change in transcription or translation of proteasome or proteasome subunits intraneuronal relocalization.

  12. Disassembly of actin structures by nanosecond pulsed electric field is a downstream effect of cell swelling.

    PubMed

    Pakhomov, Andrei G; Xiao, Shu; Pakhomova, Olga N; Semenov, Iurii; Kuipers, Marjorie A; Ibey, Bennett L

    2014-12-01

    Disruption of the actin cytoskeleton structures was reported as one of the characteristic effects of nanosecond-duration pulsed electric field (nsPEF) in both mammalian and plant cells. We utilized CHO cells that expressed the monomeric fluorescent protein (mApple) tagged to actin to test if nsPEF modifies the cell actin directly or as a consequence of cell membrane permeabilization. A train of four 600-ns pulses at 19.2 kV/cm (2 Hz) caused immediate cell membrane poration manifested by YO-PRO-1 dye uptake, gradual cell rounding and swelling. Concurrently, bright actin features were replaced by dimmer and uniform fluorescence of diffuse actin. To block the nsPEF-induced swelling, the bath buffer was isoosmotically supplemented with an electropore-impermeable solute (sucrose). A similar addition of a smaller, electropore-permeable solute (adonitol) served as a control. We demonstrated that sucrose efficiently blocked disassembly of actin features by nsPEF, whereas adonitol did not. Sucrose also attenuated bleaching of mApple-tagged actin in nsPEF-treated cells (as integrated over the cell volume), although did not fully prevent it. We conclude that disintegration of the actin cytoskeleton was a result of cell swelling, which, in turn, was caused by cell permeabilization by nsPEF and transmembrane diffusion of solutes which led to the osmotic imbalance.

  13. Role of a reducing environment in disassembly of the herpesvirus tegument

    SciTech Connect

    Newcomb, William W.; Jones, Lisa M.; Dee, Alexander; Chaudhry, Farid; Brown, Jay C.

    2012-09-15

    Initiation of infection by herpes family viruses involves a step in which most of the virus tegument becomes detached from the capsid. Detachment takes place in the host cell cytosol near the virus entry site and it is followed by dispersal of tegument proteins and disappearance of the tegument as a distinct entity. Here we describe the results of experiments designed to test the idea that the reducing environment of the cytosol may contribute to tegument detachment and disassembly. Non-ionic detergent was used to remove the membrane of purified herpes simplex virus under control and reducing conditions. The effects on the tegument were then examined by SDS-PAGE and electron microscopy. Protein analysis demonstrated that most major tegument proteins were removed under both oxidizing and reducing conditions except for UL49 which required a reducing environment. It is proposed therefore that the reducing conditions in the cytosol are involved in removal of UL49 protein. Electron microscopic analysis revealed that capsids produced under oxidizing conditions contained a coating of protein that was absent in reduced virions and which correlated uniquely with the presence of UL49. This capsid-associated layer is suggested to be the location of UL49 in the extracted virion.

  14. QIL1 mutation causes MICOS disassembly and early onset fatal mitochondrial encephalopathy with liver disease

    PubMed Central

    Guarani, Virginia; Jardel, Claude; Chrétien, Dominique; Lombès, Anne; Bénit, Paule; Labasse, Clémence; Lacène, Emmanuelle; Bourillon, Agnès; Imbard, Apolline; Benoist, Jean-François; Dorboz, Imen; Gilleron, Mylène; Goetzman, Eric S; Gaignard, Pauline; Slama, Abdelhamid; Elmaleh-Bergès, Monique; Romero, Norma B; Rustin, Pierre; Ogier de Baulny, Hélène; Paulo, Joao A; Harper, J Wade; Schiff, Manuel

    2016-01-01

    Previously, we identified QIL1 as a subunit of mitochondrial contact site (MICOS) complex and demonstrated a role for QIL1 in MICOS assembly, mitochondrial respiration, and cristae formation critical for mitochondrial architecture (Guarani et al., 2015). Here, we identify QIL1 null alleles in two siblings displaying multiple clinical symptoms of early-onset fatal mitochondrial encephalopathy with liver disease, including defects in respiratory chain function in patient muscle. QIL1 absence in patients’ fibroblasts was associated with MICOS disassembly, abnormal cristae, mild cytochrome c oxidase defect, and sensitivity to glucose withdrawal. QIL1 expression rescued cristae defects, and promoted re-accumulation of MICOS subunits to facilitate MICOS assembly. MICOS assembly and cristae morphology were not efficiently rescued by over-expression of other MICOS subunits in patient fibroblasts. Taken together, these data provide the first evidence of altered MICOS assembly linked with a human mitochondrial disease and confirm a central role for QIL1 in stable MICOS complex formation. DOI: http://dx.doi.org/10.7554/eLife.17163.001 PMID:27623147

  15. Myosin flares and actin leptomeres as myofibril assembly/disassembly intermediates in sonic muscle fibers.

    PubMed

    Nahirney, Patrick C; Fischman, Donald A; Wang, Kuan

    2006-04-01

    The sonic muscle of type 1 male midshipman fish produces loud and enduring mating calls. Each sonic muscle fiber contains a tubular contractile apparatus with radially arranged myofibrillar plates encased in a desmin-rich cytoskeleton that is anchored to broad Z bands (approximately 1.2 micro m wide). Immunomicroscopy has revealed patches of myosin-rich "flares" emanating from the contractile tubes into the peripheral sarcoplasm along the length of the fibers. These flares contain swirls of thick filaments devoid of associated thin filaments. In other regions of the sarcoplasm at the inner surface of the sarcolemma and near Z bands, abundant ladder-like leptomeres occur with rungs every 160 nm. Leptomeres consist of dense arrays of filaments (approximately 4 nm) with a structure that resembles myofibrillar Z band structure. We propose that flares and leptomeres are distinct filamentous arrays representing site-specific processing of myofibrillar components during the assembly and disassembly of the sarcomere. Recent reports that myosin assembles into filamentous aggregates before incorporating into the A band in the skeletal muscles of vertebrates and Caenorhabditis elegans suggest that sonic fibers utilize a similar pathway. Thus, sonic muscle fibers, with their tubular design and abundant sarcoplasmic space, may provide an attractive muscle model to identify myofibrillar intermediates by structural and molecular techniques.

  16. Variations in Spontaneous Assembly and Disassembly of Molecules on Unmodified Gold Nanoparticles

    NASA Astrophysics Data System (ADS)

    Jin, Ng Zhang; Anniebell, Stanley; Gopinath, Subash C. B.; Chen, Yeng

    2016-09-01

    Electrostatic attraction, covalent binding, and hydrophobic absorption are spontaneous processes to assemble and disassemble the molecules of gold nanoparticles (GNP). This dynamic change can be performed in the presence of ions, such as NaCl or charged molecules. Current research encompasses the GNP in mediating non-biofouling and investigating the molecular attachment and detachment. Experiments were performed with different sizes of GNP and polymers. As a proof of concept, poly(ethylene glycol)- b-poly(acrylic acid), called PEG-PAAc, attachment and binding events between factor IX and factor IX-bp from snake venom were demonstrated, and the variations with these molecular attachment on GNP were shown. Optimal concentration of NaCl for GNP aggregation was 250 mM, and the optimal size of GNP used was 30 nm. The polymer PEG-PAAc (1 mg/ml) has a strong affinity to the GNP as indicated by the dispersed GNP. The concentration of 5800 nM of factor IX was proved to be optimal for dispersion of GNP, and at least 100 nM of factor IX-bp was needed to remove factor IX from the surface of GNP. This study delineates the usage of unmodified GNP for molecular analysis and downstream applications.

  17. Histone Acetylation near the Nucleosome Dyad Axis Enhances Nucleosome Disassembly by RSC and SWI/SNF

    PubMed Central

    Chatterjee, Nilanjana; North, Justin A.; Dechassa, Mekonnen Lemma; Manohar, Mridula; Prasad, Rashmi; Luger, Karolin; Ottesen, Jennifer J.; Poirier, Michael G.

    2015-01-01

    Signaling associated with transcription activation occurs through posttranslational modification of histones and is best exemplified by lysine acetylation. Lysines are acetylated in histone tails and the core domain/lateral surface of histone octamers. While acetylated lysines in histone tails are frequently recognized by other factors referred to as “readers,” which promote transcription, the mechanistic role of the modifications in the lateral surface of the histone octamer remains unclear. By using X-ray crystallography, we found that acetylated lysines 115 and 122 in histone H3 are solvent accessible, but in biochemical assays they appear not to interact with the bromodomains of SWI/SNF and RSC to enhance recruitment or nucleosome mobilization, as previously shown for acetylated lysines in H3 histone tails. Instead, we found that acetylation of lysines 115 and 122 increases the predisposition of nucleosomes for disassembly by SWI/SNF and RSC up to 7-fold, independent of bromodomains, and only in conjunction with contiguous nucleosomes. Thus, in combination with SWI/SNF and RSC, acetylation of lateral surface lysines in the histone octamer serves as a crucial regulator of nucleosomal dynamics distinct from the histone code readers and writers. PMID:26416878

  18. Interface-induced disassembly of a self-assembled two-component nanoparticle system.

    PubMed

    Gao, Yan; Duc, Le T; Ali, Affira; Liang, Beverly; Liang, Jenn-Tai; Dhar, Prajnaparamita

    2013-03-19

    We present a study of static and dynamic interfacial properties of self-assembled polyelectrolyte complex nanoparticles (size 110-120 nm) containing entrapped surfactant molecules at a fluid/fluid interface. Surface tension vs time measurements of an aqueous solution of these polyelectrolyte complex nanoparticles (PCNs) show a concentration-dependent biphasic adsorption to the air/water interface while interfacial microrheology data show a concentration-dependent initial increase in the surface viscosity (up to 10(-7) N·m/s), followed by a sharp decrease (10(-9) N·m/s). Direct visualization of the air/water interface shows disappearance of particles from the interface over time. On the basis of these observations, we propose that the PCNs at fluid/fluid interfaces exist in two states: initial accumulation of PCNs at the air/water interface as nanoparticles, followed by interface induced disassembly of the accumulated PCNs into their components. The lack of change in particle size, charge, and viscosity of the bulk aqueous solution of PCNs with time indicates that this disintegration of the self-assembled PCNs is an interfacial phenomenon. Changes in energy encountered by the PCNs at the interface lead to instability of the self-assembled system and dissociation into its components. Such systems can be used for applications requiring directed delivery and triggered release of entrapped surfactants or macromolecules at fluid/fluid interfaces.

  19. The acetylation of alpha-tubulin and its relationship to the assembly and disassembly of microtubules

    PubMed Central

    1986-01-01

    A tight association between Chlamydomonas alpha-tubulin acetyltransferase (TAT) and flagellar axonemes, and the cytoplasmic localization of both tubulin deacetylase (TDA) and an inhibitor of tubulin acetylation have been demonstrated by the use of calf brain tubulin as substrate for these enzymes. A major axonemal TAT of 130 kD has been solubilized by high salt treatment, purified, and characterized. Using the Chlamydomonas TAT with brain tubulin as substrate, we have studied the effects of acetylation on the assembly and disassembly of microtubules in vitro. We also determined the relative rates of acetylation of tubulin dimers and polymers. The acetylation does not significantly affect the temperature-dependent polymerization or depolymerization of tubulin in vitro. Furthermore, polymerization of tubulin is not a prerequisite for the acetylation, although the polymer is a better substrate for TAT than the dimer. The acetylation is sensitive to calcium ions which completely inhibit the acetylation of both dimers and polymers of tubulin. Acetylation of the dimer is not inhibited by colchicine; the effect of colchicine on acetylation of the polymer can be explained by its depolymerizing effect on the polymer. PMID:3733880

  20. Ipl1/Aurora B kinase coordinates synaptonemal complex disassembly with cell cycle progression and crossover formation in budding yeast meiosis

    PubMed Central

    Jordan, Philip; Copsey, Alice; Newnham, Louise; Kolar, Elizabeth; Lichten, Michael; Hoffmann, Eva

    2009-01-01

    Several protein kinases collaborate to orchestrate and integrate cellular and chromosomal events at the G2/M transition in both mitotic and meiotic cells. During the G2/M transition in meiosis, this includes the completion of crossover recombination, spindle formation, and synaptonemal complex (SC) breakdown. We identified Ipl1/Aurora B kinase as the main regulator of SC disassembly. Mutants lacking Ipl1 or its kinase activity assemble SCs with normal timing, but fail to dissociate the central element component Zip1, as well as its binding partner, Smt3/SUMO, from chromosomes in a timely fashion. Moreover, lack of Ipl1 activity causes delayed SC disassembly in a cdc5 as well as a CDC5-inducible ndt80 mutant. Crossover levels in the ipl1 mutant are similar to those observed in wild type, indicating that full SC disassembly is not a prerequisite for joint molecule resolution and subsequent crossover formation. Moreover, expression of meiosis I and meiosis II-specific B-type cyclins occur normally in ipl1 mutants, despite delayed formation of anaphase I spindles. These observations suggest that Ipl1 coordinates changes to meiotic chromosome structure with resolution of crossovers and cell cycle progression at the end of meiotic prophase. PMID:19759266

  1. Intermediates in assembly by photoactivation after thermally accelerated disassembly of the manganese complex of photosynthetic water oxidation.

    PubMed

    Barra, Marcos; Haumann, Michael; Loja, Paola; Krivanek, Roland; Grundmeier, Alexander; Dau, Holger

    2006-12-05

    The Mn4Ca complex bound to photosystem II (PSII) is the active site of photosynthetic water oxidation. Its assembly involves binding and light-driven oxidation of manganese, a process denoted as photoactivation. The disassembly of the Mn complex is a thermally activated process involving distinct intermediates. Starting from intermediate states of the disassembly, which was initiated by a temperature jump to 47 degrees C, we photoactivated PSII membrane particles and monitored the activity recovery by O2 polarography and delayed chlorophyll fluorescence measurements. Oxidation state and structural features of the formed intermediates of the Mn complex were assayed by X-ray absorption spectroscopy at the Mn K-edge. The photoactivation time courses, which exhibit a lag phase characteristic of intermediate formation only when starting with the apo-PSII, suggest that within approximately 5 min of photoactivation of apo-PSII, a binuclear Mn complex is formed. It is proposed that a MnIII2(di-mu-oxo) complex is a key intermediate both in the disassembly and in the assembly reaction paths.

  2. Modulation of p-eIF2α cellular levels and stress granule assembly/disassembly by trehalose

    PubMed Central

    Dimasi, Pasquale; Quintiero, Annamaria; Shelkovnikova, Tatyana A.; Buchman, Vladimir L.

    2017-01-01

    Stress granules (SGs) are an important component of cellular stress response. Compromised assembly of SGs as well as their premature or delayed disassembly affect physiology and survival of cells under stress or during recovery from stress. Consequently, abnormal turnover of SGs has been implicated in the development of various pathologies, including neurodegeneration. We found that pretreatment of cells with a natural disaccharide trehalose, a known autophagy enhancer, delays SG assembly and facilitates their premature post-stress disassembly. Mechanistically, the effect of trehalose on SGs is mediated via the p-eIF2α rather than autophagosome pathway. Trehalose increases pre-stress levels of p-eIF2α and its phosphatase subunits and promotes post-stress translational recovery. Upon prolonged treatment, trehalose impairs basal translation affecting production of transiently expressed proteins. Early translational recovery and SG disassembly induced by trehalose pretreatment can sensitise cells to stress and impair survival. Our study has important implications for the use of trehalose in studies of autophagic clearance of misfolded proteins and for targeting SGs as a possible therapeutic approach in neurodegenerative and other diseases. PMID:28276506

  3. VE-Cadherin Disassembly and Cell Contractility in the Endothelium are Necessary for Barrier Disruption Induced by Tumor Cells

    PubMed Central

    Aragon-Sanabria, Virginia; Pohler, Steven E.; Eswar, Vikram J.; Bierowski, Matthew; Gomez, Esther W.; Dong, Cheng

    2017-01-01

    During metastasis, breakdown of the endothelial barrier is critical for tumor cell extravasation through blood vessel walls and is mediated by a combination of tumor secreted soluble factors and receptor-ligand interactions. However, a complete mechanism governing tumor cell transendothelial migration remains unclear. Here, we investigate the roles of tumor-associated signals in regulating endothelial cell contractility and adherens junction disassembly leading to endothelial barrier breakdown. We show that Src mediates VE-cadherin disassembly in response to metastatic melanoma cells. Through the use of pharmacological inhibitors of cytoskeletal contractility we find that endothelial cell contractility is responsive to interactions with metastatic cancer cells and that reducing endothelial cell contractility abrogates migration of melanoma cells across endothelial monolayers. Furthermore, we find that a combination of tumor secreted soluble factors and receptor-ligand interactions mediate activation of Src within endothelial cells that is necessary for phosphorylation of VE-cadherin and for breakdown of the endothelial barrier. Together, these results provide insight into how tumor cell signals act in concert to modulate cytoskeletal contractility and adherens junctions disassembly during extravasation and may aid in identification of therapeutic targets to block metastasis. PMID:28393886

  4. Antofine-induced connexin43 gap junction disassembly in rat astrocytes involves protein kinase Cβ.

    PubMed

    Huang, Yu-Fang; Liao, Chih-Kai; Lin, Jau-Chen; Jow, Guey-Mei; Wang, Hwai-Shi; Wu, Jiahn-Chun

    2013-03-01

    Antofine, a phenanthroindolizidine alkaloid derived from Cryptocaryachinensis and Ficusseptica in the Asclepiadaceae milkweed family, is cytotoxic for various cancer cell lines. In this study, we demonstrated that treatment of rat primary astrocytes with antofine induced dose-dependent inhibition of gap junction intercellular communication (GJIC), as assessed by scrape-loading 6-carboxyfluorescein dye transfer. Levels of Cx43 protein were also decreased in a dose- and time-dependent manner following antofine treatment. Double-labeling immunofluorescence microscopy showed that antofine (10ng/ml) induced endocytosis of surface gap junctions into the cytoplasm, where Cx43 was co-localized with the early endosome marker EEA1. Inhibition of lysosomes or proteasomes by co-treatment with antofine and their respective specific inhibitors, NH4Cl or MG132, partially inhibited the antofine-induced decrease in Cx43 protein levels, but did not inhibit the antofine-induced inhibition of GJIC. After 30min of treatment, antofine induced a rapid increase in the intracellular Ca(2+) concentration and activation of protein kinase C (PKC)α/βII, which was maintained for at least 6h. Co-treatment of astrocytes with antofine and the intracellular Ca(2+) chelator BAPTA-AM prevented downregulation of Cx43 and inhibition of GJIC. Moreover, co-treatment with antofine and a specific PKCβ inhibitor prevented endocytosis of gap junctions, downregulation of Cx43, and inhibition of GJIC. Taken together, these findings indicate that antofine induces Cx43 gap junction disassembly by the PKCβ signaling pathway. Inhibition of GJIC by antofine may undermine the neuroprotective effect of astrocytes in CNS.

  5. Assembly and disassembly of spliceosomes along a specific pre-messenger RNP fiber.

    PubMed

    Kiseleva, E; Wurtz, T; Visa, N; Daneholt, B

    1994-12-15

    Transcriptionally active Balbiani ring (BR) genes in the salivary glands of the dipteran Chironomus tentans were studied by immunoelectron microscopy to establish the distribution of spliceosome components along a specific pre-messenger ribonucleoprotein (pre-mRNP) fiber. The BR genes are 35-40 kb in size with three introns close to the 5' end and one close to the 3' end; a very large middle portion lacks introns. As a rule the 5' introns are spliced concomitant with transcription in the promoter proximal third of the gene, while the 3' intron is spliced post-transcriptionally. The BR genes with growing pre-mRNPs were visualized in situ, while completed and released pre-mRNPs were isolated from the nucleoplasm and studied unfolded on a grid surface. An anti-snRNP antibody (Y12) bound mainly to the promoter proximal third of the BR gene (86%) and only to a minor extent to the middle and distal thirds (7 and 7% respectively). An antibody to an hnRNP protein reacted with the proximal, middle and distal regions to an increasing extent (17, 38 and 45% respectively), reflecting the increase in size of the growing transcription product. In the nucleoplasmic pre-mRNP particle only one end of the RNP fiber was labeled by Y 12, presumably the 3' end; the anti-hnRNP antibody decorated the entire RNP fiber. Thus, the snRNPs do not associate along the whole pre-mRNP fiber but rather bind to the 5' and 3' ends, i.e. the regions containing the introns. The results also imply that the spliceosomes both assemble and disassemble rapidly on the pre-mRNP fiber.

  6. p31comet promotes disassembly of the mitotic checkpoint complex in an ATP-dependent process

    PubMed Central

    Teichner, Adar; Eytan, Esther; Sitry-Shevah, Danielle; Miniowitz-Shemtov, Shirly; Dumin, Elena; Gromis, Jonathan; Hershko, Avram

    2011-01-01

    Accurate segregation of chromosomes in mitosis is ensured by a surveillance mechanism called the mitotic (or spindle assembly) checkpoint. It prevents sister chromatid separation until all chromosomes are correctly attached to the mitotic spindle through their kinetochores. The checkpoint acts by inhibiting the anaphase-promoting complex/cyclosome (APC/C), a ubiquitin ligase that targets for degradation securin, an inhibitor of anaphase initiation. The activity of APC/C is inhibited by a mitotic checkpoint complex (MCC), composed of the APC/C activator Cdc20 bound to the checkpoint proteins MAD2, BubR1, and Bub3. When all kinetochores acquire bipolar attachment the checkpoint is inactivated, but the mechanisms of checkpoint inactivation are not understood. We have previously observed that hydrolyzable ATP is required for exit from checkpoint-arrested state. In this investigation we examined the possibility that ATP hydrolysis in exit from checkpoint is linked to the action of the Mad2-binding protein p31comet in this process. It is known that p31comet prevents the formation of a Mad2 dimer that it thought to be important for turning on the mitotic checkpoint. This explains how p31comet blocks the activation of the checkpoint but not how it promotes its inactivation. Using extracts from checkpoint-arrested cells and MCC isolated from such extracts, we now show that p31comet causes the disassembly of MCC and that this process requires β,γ-hydrolyzable ATP. Although p31comet binds to Mad2, it promotes the dissociation of Cdc20 from BubR1 in MCC. PMID:21300909

  7. The MinCDJ System in Bacillus subtilis Prevents Minicell Formation by Promoting Divisome Disassembly

    PubMed Central

    van Baarle, Suey; Bramkamp, Marc

    2010-01-01

    Background Cell division in Bacillus subtilis takes place precisely at midcell, through the action of Noc, which prevents division from occurring over the nucleoids, and the Min system, which prevents cell division from taking place at the poles. Originally it was thought that the Min system acts directly on FtsZ, preventing the formation of a Z-ring and, therefore, the formation of a complete cytokinetic ring at the poles. Recently, a new component of the B. subtilis Min system was identified, MinJ, which acts as a bridge between DivIVA and MinCD. Methodology/Principal Findings We used fluorescence microscopy and molecular genetics to examine the molecular role of MinJ. We found that in the absence of a functional Min system, FtsA, FtsL and PBP-2B remain associated with completed division sites. Evidence is provided that MinCDJ are responsible for the failure of these proteins to localize properly, indicating that MinCDJ can act on membrane integral components of the divisome. Conclusions/Significance Taken together, we postulate that the main function of the Min system is to prevent minicell formation adjacent to recently completed division sites by promoting the disassembly of the cytokinetic ring, thereby ensuring that cell division occurs only once per cell cycle. Thus, the role of the Min system in rod-shaped bacteria seems not to be restricted to an inhibitory function on FtsZ polymerization, but can act on different levels of the divisome. PMID:20352045

  8. Preparation of Segmented Microtubules to Study Motions Driven by the Disassembling Microtubule Ends

    PubMed Central

    Volkov, Vladimir A.; Zaytsev, Anatoly V.; Grishchuk, Ekaterina L.

    2014-01-01

    Microtubule depolymerization can provide force to transport different protein complexes and protein-coated beads in vitro. The underlying mechanisms are thought to play a vital role in the microtubule-dependent chromosome motions during cell division, but the relevant proteins and their exact roles are ill-defined. Thus, there is a growing need to develop assays with which to study such motility in vitro using purified components and defined biochemical milieu. Microtubules, however, are inherently unstable polymers; their switching between growth and shortening is stochastic and difficult to control. The protocols we describe here take advantage of the segmented microtubules that are made with the photoablatable stabilizing caps. Depolymerization of such segmented microtubules can be triggered with high temporal and spatial resolution, thereby assisting studies of motility at the disassembling microtubule ends. This technique can be used to carry out a quantitative analysis of the number of molecules in the fluorescently-labeled protein complexes, which move processively with dynamic microtubule ends. To optimize a signal-to-noise ratio in this and other quantitative fluorescent assays, coverslips should be treated to reduce nonspecific absorption of soluble fluorescently-labeled proteins. Detailed protocols are provided to take into account the unevenness of fluorescent illumination, and determine the intensity of a single fluorophore using equidistant Gaussian fit. Finally, we describe the use of segmented microtubules to study microtubule-dependent motions of the protein-coated microbeads, providing insights into the ability of different motor and nonmotor proteins to couple microtubule depolymerization to processive cargo motion. PMID:24686554

  9. FRET-labeled siRNA probes for tracking assembly and disassembly of siRNA nanocomplexes.

    PubMed

    Alabi, Christopher A; Love, Kevin T; Sahay, Gaurav; Stutzman, Tina; Young, Whitney T; Langer, Robert; Anderson, Daniel G

    2012-07-24

    The assembly, stability, and timely disassembly of short interfering RNA (siRNA) nanocomplexes have the potential to affect the efficiency of siRNA delivery and gene silencing. As such, the design of new probes that can measure these properties without significantly perturbing the nanocomplexes or their environment may facilitate the study and further development of new siRNA nanocomplexes. Herein, we study Förster resonance energy transfer (FRET)-labeled siRNA probes that can track the assembly, stability, and disassembly of siRNA nanocomplexes in different environments. The probe is composed of two identical siRNAs, each labeled with a fluorophore. Upon nanocomplex formation, the siRNA-bound fluorophores become locally aggregated within the nanocomplex and undergo FRET. A key advantage of this technique is that the delivery vehicle (DV) need not be labeled, thus enabling the characterization of a large variety of nanocarriers, some of which may be difficult or even impossible to label. We demonstrate proof-of-concept by measuring the assembly of various DVs with siRNAs and show good agreement with gel electrophoresis experiments. As a consequence of not having to label the DV, we are able to determine nanocomplex biophysical parameters such as the extracellular apparent dissociation constants (K(D)) and intracellular disassembly half-life for several in-house and proprietary commercial DVs. Furthermore, the lack of DV modification allows for a true direct comparison between DVs as well as correlation between their biophysical properties and gene silencing.

  10. Basic residue at position 14 is not required for fast assembly and disassembly kinetics in neural cadherin.

    PubMed

    Vunnam, Nagamani; Hammer, Nathan I; Pedigo, Susan

    2015-01-27

    In spite of their structural similarities, epithelial (E-) and neural (N-) cadherin are expressed at different types of synapses and differ significantly in their dimerization kinetics. Recent studies proposed a transient intermediate in E-cadherin as the key requirement for rapid disassembly kinetics of the adhesive dimer. This E-cadherin intermediate comprises four intermolecular ionic and H-bonding interactions between adhesive partners. These interactions are not preserved in N-cadherin except for a basic residue at the 14th position, which could stabilize the intermediate through either H-bonding or ionic interactions with the partner protomer. To investigate the origin of the rapid dimerization kinetics of N-cadherin in the presence of calcium, studies reported here systematically test the role of ionic and H-bonding interactions in dimerization kinetics using R14S, R14A, and R14E mutants of N-cadherin. Analytical size-exclusion chromatographic and bead aggregation studies showed two primary results. First, N-cadherin/R14S and N-cadherin/R14A mutants showed fast assembly and disassembly kinetics in the calcium-saturated state similar to that of wild-type N-cadherin. These results indicate that the fast disassembly of the calcium-saturated dimer of N-cadherin does not require a basic residue at the 14th position. Second, the dimerization kinetics of N-cadherin/R14E were slow in the calcium-saturated state, indicating that negative charge destabilizes the intermediate state. Taken together, these results indicate that the basic residue at the 14th position does not promote rapid dimerization kinetics but that an acidic amino acid in that position significantly impairs dimerization kinetics.

  11. Sequence-defined Energetic Shifts Control the Disassembly Kinetics and Microstructure of Amelogenin Adsorbed onto Hydroxyapatite (100)

    SciTech Connect

    Tao, Jinhui; Buchko, Garry W.; Shaw, Wendy J.; De Yoreo, Jim; Tarasevich, Barbara J.

    2015-11-03

    The interactions between proteins and surfaces are critical to a number of important processes including biomineralization, the biocompatibility of biomaterials, and the function of biosensors. Although many proteins exist as monomers or small oligomers, amelogenin is a unique protein that self-assembles into supramolecular structures called “nanospheres,” aggregates of 100’s of monomers that are 20-60 nm in diameter. The nanosphere quaternary structure is observed in solution, however, the quaternary structure of amelogenin adsorbed onto hydroxyapatite (HAP) surfaces is not known even though it may be important to amelogenin’s function in forming highly elongated and intricately assembled HAP crystallites during enamel formation. We report studies of the interactions of the enamel protein, amelogenin (rpM179), with a well-defined (100) face prepared by synthesis of large crystals of HAP. High resolution, in-situ atomic force microscopy (AFM) was used to directly observe protein adsorption onto HAP at the molecular level within an aqueous solution environment. Our study shows that the amelogenin nanospheres disassemble onto the HAP surface, breaking down into oligomeric (25-mer) subunits of the larger nanosphere. In some cases, the disassembly event is directly observed by in situ imaging for the first time. Quantification of the adsorbate amounts by size analysis led to the determination of a protein binding energy (17.1 kbT) to a specific face of HAP (100). The kinetics of disassembly are greatly slowed in aged solutions, indicating there are time-dependent increases in oligomer-oligomer binding interactions within the nanosphere. A small change in the sequence of amelogenin by the attachment of a histidine tag to the N-terminus of rpM179 to form rp(H)M180 results in the adsorption of a complete second layer on top of the underlying first layer. Our research elucidates how supramolecular protein structures interact and break down at surfaces and how small

  12. Intra-procedural Path-insensitve Grams (I-GRAMS) and Disassembly Based Features for Packer Tool Classification and Detection

    DTIC Science & Technology

    2012-06-14

    Captain, USAF AFIT/ GCE /ENG/12-07 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio...Government and is not subject to copyright protection in the United States AFIT/ GCE /ENG/12-07 INTRA-PROCEDURAL PATH-INSENSITIVE GRAMS (I-GRAMS) AND...PUBLIC RELEASE; DISTRIBUTION UNLIMITED AFIT/ GCE /ENG/12-07 INTRA-PROCEDURAL PATH-INSENSITIVE GRAMS (I-GRAMS) AND DISASSEMBLY BASED FEATURES FOR PACKER

  13. Actin-interacting Protein 1 Promotes Disassembly of Actin-depolymerizing Factor/Cofilin-bound Actin Filaments in a pH-dependent Manner*

    PubMed Central

    Nomura, Kazumi; Hayakawa, Kimihide; Tatsumi, Hitoshi; Ono, Shoichiro

    2016-01-01

    Actin-interacting protein 1 (AIP1) is a conserved WD repeat protein that promotes disassembly of actin filaments when actin-depolymerizing factor (ADF)/cofilin is present. Although AIP1 is known to be essential for a number of cellular events involving dynamic rearrangement of the actin cytoskeleton, the regulatory mechanism of the function of AIP1 is unknown. In this study, we report that two AIP1 isoforms from the nematode Caenorhabditis elegans, known as UNC-78 and AIPL-1, are pH-sensitive in enhancement of actin filament disassembly. Both AIP1 isoforms only weakly enhance disassembly of ADF/cofilin-bound actin filaments at an acidic pH but show stronger disassembly activity at neutral and basic pH values. However, a severing-defective mutant of UNC-78 shows pH-insensitive binding to ADF/cofilin-decorated actin filaments, suggesting that the process of filament severing or disassembly, but not filament binding, is pH-dependent. His-60 of AIP1 is located near the predicted binding surface for the ADF/cofilin-actin complex, and an H60K mutation of AIP1 partially impairs its pH sensitivity, suggesting that His-60 is involved in the pH sensor for AIP1. These biochemical results suggest that pH-dependent changes in AIP1 activity might be a novel regulatory mechanism of actin filament dynamics. PMID:26747606

  14. San Mateo Creek Basin

    EPA Pesticide Factsheets

    The San Mateo Creek Basin comprises approximately 321 square miles within the Rio San Jose drainage basin in McKinley and Cibola counties, New Mexico. This basin is located within the Grants Mining District (GMD).

  15. Overexpression of MLN51 triggers P-body disassembly and formation of a new type of RNA granules.

    PubMed

    Cougot, Nicolas; Daguenet, Elisabeth; Baguet, Aurélie; Cavalier, Annie; Thomas, Daniel; Bellaud, Pascale; Fautrel, Alain; Godey, Florence; Bertrand, Edouard; Tomasetto, Catherine; Gillet, Reynald

    2014-11-01

    Metastatic lymph node 51 (MLN51, also known as CASC3) is a core component of the exon junction complex (EJC), which is loaded onto spliced mRNAs and plays an essential role in determining their fate. Unlike the three other EJC core components [eIF4AIII, Magoh and Y14 (also known as RBM8A)], MLN51 is mainly located in the cytoplasm, where it plays a key role in the assembly of stress granules. In this study, we further investigated the cytoplasmic role of MLN51. We show that MLN51 is a new component of processing bodies (P-bodies). When overexpressed, MLN51 localizes in novel small cytoplasmic foci. These contain RNA, show directed movements and are distinct from stress granules and P-bodies. The appearance of these foci correlates with the process of P-body disassembly. A similar reduction in P-body count is also observed in human HER2-positive (HER2(+)) breast cancer cells overexpressing MLN51. This suggests that P-body disassembly and subsequent mRNA deregulation might correlate with cancer progression.

  16. Disassembly of the self-assembled, double-ring structure of proteasome α7 homo-tetradecamer by α6.

    PubMed

    Ishii, Kentaro; Noda, Masanori; Yagi, Hirokazu; Thammaporn, Ratsupa; Seetaha, Supaporn; Satoh, Tadashi; Kato, Koichi; Uchiyama, Susumu

    2015-12-14

    The 20S core particle of the eukaryotic proteasome is composed of two α- and two β-rings, each of which is a hetero-heptamer composed of seven homologous but distinct subunits. Although formation of the eukaryotic proteasome is a highly ordered process assisted by assembly chaperones, α7, an α-ring component, has the unique property of self-assembling into a homo-tetradecamer. We used biophysical methods to characterize the oligomeric states of this proteasome subunit and its interaction with α6, which makes direct contacts with α7 in the proteasome α-ring. We determined a crystal structure of the α7 tetradecamer, which has a double-ring structure. Sedimentation velocity analytical ultracentrifugation and mass spectrometric analysis under non-denaturing conditions revealed that α7 exclusively exists as homo-tetradecamer in solution and that its double-ring structure is disassembled upon the addition of α6, resulting in a 1:7 hetero-octameric α6-α7 complex. Our findings suggest that proteasome formation involves the disassembly of non-native oligomers, which are assembly intermediates.

  17. RHGF-1/PDZ-RhoGEF and retrograde DLK-1 signaling drive neuronal remodeling on microtubule disassembly

    PubMed Central

    Chen, Chun-Hao; Lee, Albert; Liao, Chien-Po; Liu, Ya-Wen; Pan, Chun-Liang

    2014-01-01

    Neurons remodel their connectivity in response to various insults, including microtubule disruption. How neurons sense microtubule disassembly and mount remodeling responses by altering genetic programs in the soma are not well defined. Here we show that in response to microtubule disassembly, the Caenorhabditis elegans PLM neuron remodels by retracting its synaptic branch and overextending the primary neurite. This remodeling required RHGF-1, a PDZ-Rho guanine nucleotide exchange factor (PDZ-RhoGEF) that was associated with and inhibited by microtubules. Independent of the myosin light chain activation, RHGF-1 acted through Rho-dependent kinase LET-502/ROCK and activated a conserved, retrograde DLK-1 MAPK (DLK-1/dual leucine zipper kinase) pathway, which triggered synaptic branch retraction and overgrowth of the PLM neurite in a dose-dependent manner. Our data represent a neuronal remodeling paradigm during development that reshapes the neural circuit by the coordinated removal of the dysfunctional synaptic branch compartment and compensatory extension of the primary neurite. PMID:25359212

  18. Dual chemotaxis signalling regulates Dictyostelium development: intercellular cyclic AMP pulses and intracellular F-actin disassembly waves induce each other.

    PubMed

    Vicker, Michael G; Grutsch, James F

    2008-10-01

    Aggregating Dictyostelium discoideum amoebae periodically emit and relay cAMP, which regulates their chemotaxis and morphogenesis into a multicellular, differentiated organism. Cyclic AMP also stimulates F-actin assembly and chemotactic pseudopodium extension. We used actin-GFP expression to visualise for the first time intracellular F-actin assembly as a spatio-temporal indicator of cell reactions to cAMP, and thus the kinematics of cell communication, in aggregating streams. Every natural cAMP signal pulse induces an autowave of F-actin disassembly, which propagates from each cell's leading end to its trailing end at a linear rate, much slower than the calculated and measured velocities of cAMP diffusion in aggregating Dictyostelium. A sequence of transient reactions follows behind the wave, including anterior F-actin assembly, chemotactic pseudopodium extension and cell advance at the cell front and, at the back, F-actin assembly, extension of a small retrograde pseudopodium (forcing a brief cell retreat) and chemotactic stimulation of the following cell, yielding a 20s cAMP relay delay. These dynamics indicate that stream cell behaviour is mediated by a dual signalling system: a short-range cAMP pulse directed from one cell tail to an immediately following cell front and a slower, long-range wave of intracellular F-actin disassembly, each inducing the other.

  19. Resistance of Dynamin-related Protein 1 Oligomers to Disassembly Impairs Mitophagy, Resulting in Myocardial Inflammation and Heart Failure.

    PubMed

    Cahill, Thomas J; Leo, Vincenzo; Kelly, Matthew; Stockenhuber, Alexander; Kennedy, Nolan W; Bao, Leyuan; Cereghetti, Grazia; Harper, Andrew R; Czibik, Gabor; Lao, Chunyan; Bellahcene, Mohamed; Steeples, Violetta; Ghaffari, Safar; Yavari, Arash; Mayer, Alice; Poulton, Joanna; Ferguson, David J P; Scorrano, Luca; Hettiarachchi, Nishani T; Peers, Chris; Boyle, John; Hill, R Blake; Simmons, Alison; Watkins, Hugh; Dear, T Neil; Ashrafian, Houman

    2015-10-23

    We have reported previously that a missense mutation in the mitochondrial fission gene Dynamin-related protein 1 (Drp1) underlies the Python mouse model of monogenic dilated cardiomyopathy. The aim of this study was to investigate the consequences of the C452F mutation on Drp1 protein function and to define the cellular sequelae leading to heart failure in the Python monogenic dilated cardiomyopathy model. We found that the C452F mutation increased Drp1 GTPase activity. The mutation also conferred resistance to oligomer disassembly by guanine nucleotides and high ionic strength solutions. In a mouse embryonic fibroblast model, Drp1 C452F cells exhibited abnormal mitochondrial morphology and defective mitophagy. Mitochondria in C452F mouse embryonic fibroblasts were depolarized and had reduced calcium uptake with impaired ATP production by oxidative phosphorylation. In the Python heart, we found a corresponding progressive decline in oxidative phosphorylation with age and activation of sterile inflammation. As a corollary, enhancing autophagy by exposure to a prolonged low-protein diet improved cardiac function in Python mice. In conclusion, failure of Drp1 disassembly impairs mitophagy, leading to a downstream cascade of mitochondrial depolarization, aberrant calcium handling, impaired ATP synthesis, and activation of sterile myocardial inflammation, resulting in heart failure.

  20. Disassembly of yeast 80S ribosomes into subunits is a concerted action of ribosome-assisted folding of denatured protein.

    PubMed

    Chakraborty, Biprashekhar; Bhakta, Sayan; Sengupta, Jayati

    2016-01-22

    It has been shown by several groups that ribosome can assist folding of denatured protein in vitro and the process is conserved across the species. Domain V of large ribosomal rRNA which occupies the intersubunit side of the large subunit was identified as the key player responsible for chaperoning the folding process. Thus, it is conceivable that denatured protein needs to access the intersubunit space of the ribosome in order to get folded. In this study, we have investigated the mechanism of release of the protein from the eukaryotic ribosome following reactivation. We have observed significant splitting of yeast 80S ribosome when incubated with the denatured BCAII protein. Energy-free disassembly mechanism functions in low Mg(+2) ion concentration for prokaryotic ribosomes. Eukaryotic ribosomes do not show significant splitting even at low Mg(+2) ion concentration. In this respect, denatured protein-induced disassembly of eukaryotic ribosome without the involvement of any external energy source is intriguing. For prokaryotic ribosomes, it was reported that the denatured protein induces ribosome splitting into subunits in order to access domain V-rRNA. In contrast, our results suggest an alternative mechanism for eukaryotic ribosomal rRNA-mediated protein folding and subsequent separation of the subunits by which release of the activated-protein occurs.

  1. 29 CFR Appendix B to Subpart Cc of... - Assembly/Disassembly: Sample Procedures for Minimizing the Risk of Unintended Dangerous Boom...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the Risk of Unintended Dangerous Boom Movement 1. Section 1926.1404(f)(1) provides that when pins (or... other components when pins (or similar devices) are being removed. In such a situation, the A/D director... disassembled in the air, and the employees who remove the pins must perform that work from an aerial lift...

  2. Nuclear removal during terminal lens fiber cell differentiation requires CDK1 activity: appropriating mitosis-related nuclear disassembly

    PubMed Central

    Chaffee, Blake R.; Shang, Fu; Chang, Min-Lee; Clement, Tracy M.; Eddy, Edward M.; Wagner, Brad D.; Nakahara, Masaki; Nagata, Shigekazu; Robinson, Michael L.; Taylor, Allen

    2014-01-01

    Lens epithelial cells and early lens fiber cells contain the typical complement of intracellular organelles. However, as lens fiber cells mature they must destroy their organelles, including nuclei, in a process that has remained enigmatic for over a century, but which is crucial for the formation of the organelle-free zone in the center of the lens that assures clarity and function to transmit light. Nuclear degradation in lens fiber cells requires the nuclease DNase IIβ (DLAD) but the mechanism by which DLAD gains access to nuclear DNA remains unknown. In eukaryotic cells, cyclin-dependent kinase 1 (CDK1), in combination with either activator cyclins A or B, stimulates mitotic entry, in part, by phosphorylating the nuclear lamin proteins leading to the disassembly of the nuclear lamina and subsequent nuclear envelope breakdown. Although most post-mitotic cells lack CDK1 and cyclins, lens fiber cells maintain these proteins. Here, we show that loss of CDK1 from the lens inhibited the phosphorylation of nuclear lamins A and C, prevented the entry of DLAD into the nucleus, and resulted in abnormal retention of nuclei. In the presence of CDK1, a single focus of the phosphonuclear mitotic apparatus is observed, but it is not focused in CDK1-deficient lenses. CDK1 deficiency inhibited mitosis, but did not prevent DNA replication, resulting in an overall reduction of lens epithelial cells, with the remaining cells possessing an abnormally large nucleus. These observations suggest that CDK1-dependent phosphorylations required for the initiation of nuclear membrane disassembly during mitosis are adapted for removal of nuclei during fiber cell differentiation. PMID:25139855

  3. A repeatable assembling and disassembling electrochemical aptamer cytosensor for ultrasensitive and highly selective detection of human liver cancer cells.

    PubMed

    Sun, Duanping; Lu, Jing; Chen, Zuanguang; Yu, Yanyan; Mo, Manni

    2015-07-23

    In this work, a repeatable assembling and disassembling electrochemical aptamer cytosensor was proposed for the sensitive detection of human liver hepatocellular carcinoma cells (HepG2) based on a dual recognition and signal amplification strategy. A high-affinity thiolated TLS11a aptamer, covalently attached to a gold electrode through Au-thiol interactions, was adopted to recognize and capture the target HepG2 cells. Meanwhile, the G-quadruplex/hemin/aptamer and horseradish peroxidase (HRP) modified gold nanoparticles (G-quadruplex/hemin/aptamer-AuNPs-HRP) nanoprobe was designed. It could be used for electrochemical cytosensing with specific recognition and enzymatic signal amplification of HRP and G-quadruplex/hemin HRP-mimicking DNAzyme. With the nanoprobes as recognizing probes, the HepG2 cancer cells were captured to fabricate an aptamer-cell-nanoprobes sandwich-like superstructure on a gold electrode surface. The proposed electrochemical cytosensor delivered a wide detection range from 1×10(2) to 1×10(7) cells mL(-1) and high sensitivity with a low detection limit of 30 cells mL(-1). Furthermore, after the electrochemical detection, the activation potential of -0.9 to -1.7V was performed to break Au-thiol bond and regenerate a bare gold electrode surface, while maintaining the good characteristic of being used repeatedly. The changes of gold electrode behavior after assembling and desorption processes were investigated by electrochemical impedance spectroscopy and cyclic voltammetry techniques. These results indicate that the cytosensor has great potential in disease diagnostic of cancers and opens new insight into the reusable gold electrode with repeatable assembling and disassembling in the electrochemical sensing.

  4. BASINS Technical Notes

    EPA Pesticide Factsheets

    EPA has developed several technical notes that provide in depth information on a specific function in BASINS. Technical notes can be used to answer questions users may have, or to provide additional information on the application of features in BASINS.

  5. BASINS Tutorials and Training

    EPA Pesticide Factsheets

    A series of lectures and exercises on how to use BASINS for water quality modeling and watershed assessment. The lectures follow sequentially. Companion exercises are provided for users to practice different BASINS water quality modeling techniques.

  6. Closure Report for Corrective Action Unit 117: Area 26 Pluto Disassembly Facility, Nevada Test Site, Nevada, Revision 0

    SciTech Connect

    Mark Burmeister

    2009-06-01

    This Closure Report (CR) presents information supporting the closure of Corrective Action Unit (CAU) 117: Area 26 Pluto Disassembly Facility, Nevada Test Site, Nevada. This CR complies with the requirements of the Federal Facility Agreement and Consent Order that was agreed to by the State of Nevada; U.S. Department of Energy (DOE), Environmental Management; U.S. Department of Defense; and DOE, Legacy Management. Corrective Action Unit 117 comprises Corrective Action Site (CAS) 26-41-01, Pluto Disassembly Facility, located in Area 26 of the Nevada Test Site. The purpose of this CR is to provide documentation supporting the completed corrective actions and provide data confirming that the closure objectives for CAU 117 were met. To achieve this, the following actions were performed: • Review the current site conditions, including the concentration and extent of contamination. • Implement any corrective actions necessary to protect human health and the environment. • Properly dispose of corrective action and investigation wastes. • Document Notice of Completion and closure of CAU 117 issued by the Nevada Division of Environmental Protection. From May 2008 through February 2009, closure activities were performed as set forth in the Streamlined Approach for Environmental Restoration Plan for Corrective Action Unit 117, Area 26 Pluto Disassembly Facility, Nevada Test Site, Nevada. The purpose of the activities as defined during the data quality objectives process were: • Determine whether contaminants of concern (COCs) are present. • If COCs are present, determine their nature and extent, implement appropriate corrective actions, and properly dispose of wastes. Analytes detected during the closure activities were evaluated against final action levels to determine COCs for CAU 117. Assessment of the data generated from closure activities indicated that the final action levels were exceeded for polychlorinated biphenyls (PCBs) reported as total Aroclor and

  7. The pedagogical value of Disassemble/Analyze/Assemble (DAA) activities: Assessing the potential for motivation and transfer

    NASA Astrophysics Data System (ADS)

    Dalrymple, Odesma Onika

    Undergraduate engineering institutions are currently seeking to improve recruiting practices and to retain engineering majors particularly by addressing what many studies document as a major challenge of poor instruction. There is an undisputed need for instructional practices that motivate students in addition to facilitating the transfer of learning beyond the classroom. Reverse engineering and product dissection, more broadly termed Disassemble/Analyze/Assemble (DAA) activities, have shown potential to address these concerns, based on the reviews of students and professors alike. DAA activities involve the systematic deconstruction of an artifact, the subsequent analysis and possible reconstruction of its components for the purpose of understanding the embodied fundamental concepts, design principles and developmental processes. These activities have been part of regular industry practice for some time; however, the systematic analysis of their benefits for learning and instruction is a relatively recent phenomenon. A number of studies have provided highly descriptive accounts of curricula and possible outcomes of DAA activities; but, relatively few have compared participants doing DAA activities to a control group doing more traditional activities. In this respect, two quasi-experiments were conducted as part of a first-year engineering laboratory, and it was hypothesized that students who engaged in the DAA activity would be more motivated and would demonstrate higher frequencies of transfer than the control. A DAA activity that required students to disassemble a single-use camera and analyze its components to discover how it works was compared to a step-by-step laboratory activity in the first experiment and a lecture method of instruction in the second experiment. In both experiments, over forty percent of the students that engaged in the DAA activity demonstrated the ability to transfer the knowledge gained about the functions of the camera's components and

  8. Full-time kinetics of self-assembly and disassembly in micellar solution via the generalized Smoluchowski equation with fusion and fission of surfactant aggregates

    NASA Astrophysics Data System (ADS)

    Shchekin, Alexander K.; Babintsev, Ilya A.; Adzhemyan, Loran Ts.

    2016-11-01

    Full-time kinetics of self-assembly and disassembly of spherical micelles with their fusion and fission in non-ionic micellar solutions has been considered in detail on the basis of direct numerical solutions of the generalized Smoluchowski equations describing the evolution of the time-dependent concentrations of molecular aggregates for every aggregation number. The cases of instant increase of the monomer concentration up or dilution of a surfactant solution below the critical micelle concentration at large initial deviations from the final equilibrium state have been studied. Different stages in assembly or disassembly of micelles have been described and compared with the results of the stepwise mechanism of monomer attachment-detachment described by the Becker-Döring kinetic equations. A relation of the full-time kinetics to micellar relaxation at small deviations from the equilibrium state has been checked.

  9. Surface plasmon resonance as a tool for investigation of non-covalent nanoparticle interactions in heterogeneous self-assembly & disassembly systems.

    PubMed

    Shevchenko, Konstantin G; Cherkasov, Vladimir R; Tregubov, Andrey A; Nikitin, Petr I; Nikitin, Maxim P

    2017-02-15

    Biomolecule-driven assembly of nanoparticles is a powerful and convenient approach for development of advanced nanosensors and theranostic agents with diverse "on-demand" composition and functionality. While a lot of research is being devoted to fabrication of such agents, the development of non-invasive analytical tools to monitor self-assembly/disassembly processes in real-time substantially lags behind. Here, we demonstrate the capabilities of localized surface plasmon resonance (SPR) phenomenon to study non-covalent interactions not just between plasmonic particles, but between gold nanoparticles (AuNP) and non-plasmonic ones. We show its potential to investigate assembly and performance of a novel type of advanced smart materials, namely, biocomputing agents. These agents, self-assembled from nanoparticles via biomolecular interfaces such as proteins, DNA, etc., can analyze presence of biomolecular inputs according to Boolean logic and undergo the input-induced disassembly in order to implement the proper output action. Using UV-Vis spectroscopy to monitor the assembly/disassembly processes of the basic YES-gate structure that consists of a polymer core particle with a multitude of associated gold nanoparticles, we found that the structure transformations are well-characterized by pronounced difference in SPR spectral band position (shifting up to 50nm). This SPR shift correlates remarkably well with biochemical estimation of the assembly/disassembly extent, and can provide valuable real-time kinetic analysis. We believe that the obtained data can be easily extended to other non-plasmonic nanoparticle systems having similar chemical and colloidal properties. SPR method can become a valuable addition to analytical toolbox for characterization of self-assembled smart nanosystems used in biosensing, imaging, controlled release and other applications.

  10. Nucleolar disruption and cajal body disassembly are nuclear hallmarks of DNA damage-induced neurodegeneration in purkinje cells.

    PubMed

    Baltanás, Fernando C; Casafont, Iñigo; Weruaga, Eduardo; Alonso, José R; Berciano, María T; Lafarga, Miguel

    2011-07-01

    The Purkinje cell (PC) degeneration (pcd) phenotype results from mutation in nna1 gene and is associated with the degeneration and death of PCs during the postnatal life. Although the pcd mutation is a model of the ataxic mouse, it shares clinical and pathological characteristics of inherited human spinocerebellar ataxias. PC degeneration in pcd mice provides a useful neuronal system to study nuclear mechanisms involved in DNA damage-dependent neurodegeneration, particularly the contribution of nucleoli and Cajal bodies (CBs). Both nuclear structures are engaged in housekeeping functions for neuronal survival, the biogenesis of ribosomes and the maturation of snRNPs and snoRNPs required for pre-mRNA and pre-rRNA processing, respectively. In this study, we use ultrastructural analysis, in situ transcription assay and molecular markers for DNA damage, nucleoli and CB components to demonstrate that PC degeneration involves the progressive accumulation of nuclear DNA damage associated with disruption of nucleoli and CBs, disassembly of polyribosomes into monoribosomes, ribophagy and shut down of nucleolar and extranucleolar transcription. Microarray analysis reveals that four genes encoding repressors of nucleolar rRNA synthesis (p53, Rb, PTEN and SNF2) are upregulated in the cerebellum of pcd mice. Collectively, these data support that nucleolar and CB alterations are hallmarks of DNA damage-induced neurodegeneration.

  11. Dissociation of CAK from Core TFIIH Reveals a Functional Link between XP-G/CS and the TFIIH Disassembly State

    PubMed Central

    Arab, Hany H.; Wani, Gulzar; Ray, Alo; Shah, Zubair I.; Zhu, Qianzheng; Wani, Altaf A.

    2010-01-01

    Transcription factor II H (TFIIH) is comprised of core TFIIH and Cdk-activating kinase (CAK) complexes. Here, we investigated the molecular and cellular manifestation of the TFIIH compositional changes by XPG truncation mutations. We showed that both core TFIIH and CAK are rapidly recruited to damage sites in repair-proficient cells. Chromatin immunoprecipitation against TFIIH and CAK components revealed a physical engagement of CAK in nucleotide excision repair (NER). While XPD recruitment to DNA damage was normal, CAK was not recruited in severe XP-G and XP-G/CS cells, indicating that the associations of CAK and XPD to core TFIIH are differentially affected. A CAK inhibition approach showed that CAK activity is not required for assembling pre-incision machinery in vivo or for removing genomic photolesions. Instead, CAK is involved in Ser5-phosphorylation and UV-induced degradation of RNA polymerase II. The CAK inhibition impaired transcription from undamaged and UV-damaged reporter, and partially decreased transcription of p53-dependent genes. The overall results demonstrated that a) XP-G/CS mutations affect the disassembly state of TFIIH resulting in the dissociation of CAK, but not XPD from core TFIIH, and b) CAK activity is not essential for global genomic repair but involved in general transcription and damage-induced RNA polymerase II degradation. PMID:20543986

  12. Disassembly of microtubules and inhibition of neurite outgrowth, neuroblastoma cell proliferation, and MAP kinase tyrosine dephosphorylation by dibenzyl trisulphide.

    PubMed

    Rösner, H; Williams, L A; Jung, A; Kraus, W

    2001-08-22

    Dibenzyl trisulphide (DTS), a main lipophilic compound in Petiveria alliacea L. (Phytolaccaceae), was identified as one of the active immunomodulatory compounds in extracts of the plant. To learn more about its biological activities and molecular mechanisms, we conducted one-dimensional NMR interaction studies with bovine serum albumin (BSA) and tested DTS and related compounds in two well-established neuronal cell-and-tissue culture systems. We found that DTS preferentially binds to an aromatic region of BSA which is rich in tyrosyl residues. In SH-SY5Y neuroblastoma cells, DTS attenuates the dephosphorylation of tyrosyl residues of MAP kinase (erk1/erk2). In the same neuroblastoma cell line and in Wistar 38 human lung fibroblasts, DTS causes a reversible disassembly of microtubules, but it did not affect actin dynamics. Probably due to the disruption of the microtubule dynamics, DTS also inhibits neuroblastoma cell proliferation and neurite outgrowth from spinal cord explants. Related dibenzyl compounds with none, one, or two sulphur atoms were found to be significantly less effective. These data confirmed that the natural compound DTS has a diverse spectrum of biological properties, including cytostatic and neurotoxic actions in addition to immunomodulatory activities.

  13. FAK-MAPK-dependent adhesion disassembly downstream of L1 contributes to semaphorin3A-induced collapse.

    PubMed

    Bechara, Ahmad; Nawabi, Homaira; Moret, Frédéric; Yaron, Avraham; Weaver, Eli; Bozon, Muriel; Abouzid, Karima; Guan, Jun-Lin; Tessier-Lavigne, Marc; Lemmon, Vance; Castellani, Valérie

    2008-06-04

    Axonal receptors for class 3 semaphorins (Sema3s) are heterocomplexes of neuropilins (Nrps) and Plexin-As signalling coreceptors. In the developing cerebral cortex, the Ig superfamily cell adhesion molecule L1 associates with Nrp1. Intriguingly, the genetic removal of L1 blocks axon responses of cortical neurons to Sema3A in vitro despite the expression of Plexin-As in the cortex, suggesting either that L1 substitutes for Plexin-As or that L1 and Plexin-A are both required and mediate distinct roles. We report that association of Nrp1 with L1 but not Plexin-As mediates the recruitment and activation of a Sema3A-induced focal adhesion kinase-mitogen-activated protein kinase cascade. This signalling downstream of L1 is needed for the disassembly of adherent points formed in growth cones and subsequently their collapse response to Sema3A. Plexin-As and L1 are coexpressed and present in common complexes in cortical neurons and both dominant-negative forms of Plexin-A and L1 impair their response to Sema3A. Consistently, Nrp1-expressing cortical projections are defective in mice lacking Plexin-A3, Plexin-A4 or L1. This reveals that specific signalling activities downstream of L1 and Plexin-As cooperate for mediating the axon guidance effects of Sema3A.

  14. A switchable self-assembling and disassembling chiral system based on a porphyrin-substituted phenylalanine-phenylalanine motif

    NASA Astrophysics Data System (ADS)

    Charalambidis, Georgios; Georgilis, Evangelos; Panda, Manas K.; Anson, Christopher E.; Powell, Annie K.; Doyle, Stephen; Moss, David; Jochum, Tobias; Horton, Peter N.; Coles, Simon J.; Linares, Mathieu; Beljonne, David; Naubron, Jean-Valère; Conradt, Jonas; Kalt, Heinz; Mitraki, Anna; Coutsolelos, Athanassios G.; Balaban, Teodor Silviu

    2016-09-01

    Artificial light-harvesting systems have until now not been able to self-assemble into structures with a large photon capture cross-section that upon a stimulus reversibly can switch into an inactive state. Here we describe a simple and robust FLFL-dipeptide construct to which a meso-tetraphenylporphyrin has been appended and which self-assembles to fibrils, platelets or nanospheres depending on the solvent composition. The fibrils, functioning as quenched antennas, give intense excitonic couplets in the electronic circular dichroism spectra which are mirror imaged if the unnatural FDFD-analogue is used. By slightly increasing the solvent polarity, these light-harvesting fibres disassemble to spherical structures with silent electronic circular dichroism spectra but which fluoresce. Upon further dilution with the nonpolar solvent, the intense Cotton effects are recovered, thus proving a reversible switching. A single crystal X-ray structure shows a head-to-head arrangement of porphyrins that explains both their excitonic coupling and quenched fluorescence.

  15. Endorepellin causes endothelial cell disassembly of actin cytoskeleton and focal adhesions through alpha2beta1 integrin.

    PubMed

    Bix, Gregory; Fu, Jian; Gonzalez, Eva M; Macro, Laura; Barker, Amy; Campbell, Shelly; Zutter, Mary M; Santoro, Samuel A; Kim, Jiyeun K; Höök, Magnus; Reed, Charles C; Iozzo, Renato V

    2004-07-05

    Endorepellin, the COOH-terminal domain of the heparan sulfate proteoglycan perlecan, inhibits several aspects of angiogenesis. We provide evidence for a novel biological axis that links a soluble fragment of perlecan protein core to the major cell surface receptor for collagen I, alpha2beta1 integrin, and provide an initial investigation of the intracellular signaling events that lead to endorepellin antiangiogenic activity. The interaction between endorepellin and alpha2beta1 integrin triggers a unique signaling pathway that causes an increase in the second messenger cAMP; activation of two proximal kinases, protein kinase A and focal adhesion kinase; transient activation of p38 mitogen-activated protein kinase and heat shock protein 27, followed by a rapid down-regulation of the latter two proteins; and ultimately disassembly of actin stress fibers and focal adhesions. The end result is a profound block of endothelial cell migration and angiogenesis. Because perlecan is present in both endothelial and smooth muscle cell basement membranes, proteolytic activity during the initial stages of angiogenesis could liberate antiangiogenic fragments from blood vessels' walls, including endorepellin.

  16. Biomedical Exploitation of Chitin and Chitosan via Mechano-Chemical Disassembly, Electrospinning, Dissolution in Imidazolium Ionic Liquids, and Supercritical Drying

    PubMed Central

    Muzzarelli, Riccardo A. A.

    2011-01-01

    Recently developed technology permits to optimize simultaneously surface area, porosity, density, rigidity and surface morphology of chitin-derived materials of biomedical interest. Safe and ecofriendly disassembly of chitin has superseded the dangerous acid hydrolysis and provides higher yields and scaling-up possibilities: the chitosan nanofibrils are finding applications in reinforced bone scaffolds and composite dressings for dermal wounds. Electrospun chitosan nanofibers, in the form of biocompatible thin mats and non-wovens, are being actively studied: composites of gelatin + chitosan + polyurethane have been proposed for cardiac valves and for nerve conduits; fibers are also manufactured from electrospun particles that self-assemble during subsequent freeze-drying. Ionic liquids (salts of alkylated imidazolium) are suitable as non-aqueous solvents that permit desirable reactions to occur for drug delivery purposes. Gel drying with supercritical CO2 leads to structures most similar to the extracellular matrix, even when the chitosan is crosslinked, or in combination with metal oxides of interest in orthopedics. PMID:22131955

  17. Role of phosphorylation of Cdc20 in p31comet-stimulated disassembly of the mitotic checkpoint complex

    PubMed Central

    Miniowitz-Shemtov, Shirly; Eytan, Esther; Ganoth, Dvora; Sitry-Shevah, Danielle; Dumin, Elena; Hershko, Avram

    2012-01-01

    The mitotic checkpoint system delays anaphase until all chromosomes are correctly attached to the mitotic spindle. When the checkpoint is turned on, it promotes the formation of the mitotic checkpoint complex (MCC), which inhibits the ubiquitin ligase anaphase-promoting complex/cyclosome (APC/C). MCC is composed of the checkpoint proteins BubR1, Bub3, and Mad2 bound to the APC/C activator Cdc20. When the checkpoint is satisfied, MCC is disassembled and APC/C becomes active. Previous studies have shown that the Mad2-binding protein p31comet promotes the dissociation of Cdc20 from BubR1 in MCC in a process that requires ATP. We now show that a part of MCC dissociation is blocked by inhibitors of cyclin-dependent kinases (Cdks) and that purified Cdk1–cyclin B stimulates this process. The mutation of all eight potential Cdk phosphorylation sites of Cdc20 partially prevented its release from BubR1. Furthermore, p31comet stimulated Cdk-catalyzed phosphorylation of Cdc20 in MCC. It is suggested that the binding of p31comet to Mad2 in MCC may trigger a conformational change in Cdc20 that facilitates its phosphorylation by Cdk, and that the latter process may promote its dissociation from BubR1. PMID:22566641

  18. A switchable self-assembling and disassembling chiral system based on a porphyrin-substituted phenylalanine–phenylalanine motif

    PubMed Central

    Charalambidis, Georgios; Georgilis, Evangelos; Panda, Manas K.; Anson, Christopher E.; Powell, Annie K.; Doyle, Stephen; Moss, David; Jochum, Tobias; Horton, Peter N.; Coles, Simon J.; Linares, Mathieu; Beljonne, David; Naubron, Jean-Valère; Conradt, Jonas; Kalt, Heinz; Mitraki, Anna; Coutsolelos, Athanassios G.; Balaban, Teodor Silviu

    2016-01-01

    Artificial light-harvesting systems have until now not been able to self-assemble into structures with a large photon capture cross-section that upon a stimulus reversibly can switch into an inactive state. Here we describe a simple and robust FLFL-dipeptide construct to which a meso-tetraphenylporphyrin has been appended and which self-assembles to fibrils, platelets or nanospheres depending on the solvent composition. The fibrils, functioning as quenched antennas, give intense excitonic couplets in the electronic circular dichroism spectra which are mirror imaged if the unnatural FDFD-analogue is used. By slightly increasing the solvent polarity, these light-harvesting fibres disassemble to spherical structures with silent electronic circular dichroism spectra but which fluoresce. Upon further dilution with the nonpolar solvent, the intense Cotton effects are recovered, thus proving a reversible switching. A single crystal X-ray structure shows a head-to-head arrangement of porphyrins that explains both their excitonic coupling and quenched fluorescence. PMID:27582363

  19. Dimethyl Sulfoxide Induced Destabilization and Disassembly of Various Structural Variants of Insulin Fibrils Monitored by Vibrational Circular Dichroism.

    PubMed

    Zhang, Ge; Babenko, Viktoria; Dzwolak, Wojciech; Keiderling, Timothy A

    2015-12-15

    Dimethyl sulfoxide (DMSO) induced destabilization of insulin fibrils has been previously studied by Fourier transform infrared spectroscopy and interpreted in terms of secondary structural changes. The variation of this process for fibrils with different types of higher-order morphological structures remained unclear. Here, we utilize vibrational circular dichroism (VCD), which has been reported to provide a useful biophysical probe of the supramolecular chirality of amyloid fibrils, to characterize changes in the macroscopic chirality following DMSO-induced disassembly for two types of insulin fibrils formed under different conditions, at different reduced pH values with and without added salt and agitation. We confirm that very high concentrations of DMSO can disaggregate both types of insulin fibrils, which initially maintained a β-sheet conformation and eventually changed their secondary structure to a disordered form. The two types responded to varying concentrations of DMSO, and disaggregation followed different mechanisms. Interconversion of specific insulin fibril morphological types also occurred during the destabilization process as monitored by VCD. With transmission electron microscopy, we were able to correlate the changes in VCD sign patterns to alteration of morphology of the insulin fibrils.

  20. Evaluation of nuclear facility decommissioning projects. Three Mile Island Unit 2 reactor defueling and disassembly. Summary status report. Volume 3

    SciTech Connect

    Doerge, D.H.; Miller, R.L.; Scotti, K.S.

    1986-05-01

    This document summarizes information relating to the preparations for defueling the Three Mile Island Unit 2 (TMI-2) reactor and disassembly activities being performed concurrently with decontamination of the facility. Data have been collected from activity reports, reactor containment entry records, and other sources and entered in a computerized data sysem which permits extraction/manipulation of specific data which can be used in planning for recovery from a loss of coolant event similar to that experienced at TMI-2 on March 28, 1979. This report contains summaries of man-hours, manpower, and radiation exposures incurred during the period of April 23, 1979 to April 16, 1985, in the completion of activities related to preparation for reactor defueling. Support activities conducted outside of radiation areas are not included within the scope of this report. Computerized reports included in this document are: A chronological summary listing work performed for the period; and summary reports for each major task undertaken in connection with the specific scope of this report. Presented in chronological order for the referenced time period. Manually-assembled table summaries are included for: Labor and exposures by department; and labor and exposures by major activity.

  1. New aspects of the structure of human hair on the basis of optical microscopic observations of disassembled hair parts.

    PubMed

    Yamauchi, Asao; Yamauchi, Kiyoshi

    2015-01-01

    Infant' and adult' scalp hair fibers were disassembled to various cellular components and blocks by chemical and enzymatic treatments, followed by random scission with rapidly rotating cutters. The hair fibers were also fractured by the use of a vise. The optical microscopic inspection of these specimens led to the discovery of many previously unknown structures in the hair shaft. In particular, a cuticular cell (Cu) was found to take a trowel-like shape consisting of a part with a blade-like shape (CuB) and a part with a handle-like shape (CuH), where CuB overlapped one another and fused partially to build the honeycomb-like structure on a large cuticular thin plate (CuP). Whereas CuH was closely similar to the cortical cell in dimensions and richness of macrofibrils (Mf). It was considered that human hair is stabilized structurally and physicochemically by the presence of the honeycomb-like structure, the CuP and the Mf.

  2. Final Status Survey Report for Corrective Action Unit 117 - Pluto Disassembly Facility, Building 2201, Nevada National Security Site, Nevada

    SciTech Connect

    Jeremy Gwin and Douglas Frenette

    2010-09-30

    This document contains the process knowledge, radiological data and subsequent statistical methodology and analysis to support approval for the radiological release of Corrective Action Unit (CAU) 117 – Pluto Disassembly Facility, Building 2201 located in Area 26 of the Nevada National Security Site (NNSS). Preparations for release of the building began in 2009 and followed the methodology described in the Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM). MARSSIM is the DOE approved process for release of Real Property (buildings and landmasses) to a set of established criteria or authorized limits. The pre-approved authorized limits for surface contamination values and corresponding assumptions were established by DOE O 5400.5. The release criteria coincide with the acceptance criteria of the U10C landfill permit. The U10C landfill is the proposed location to dispose of the radiologically non-impacted, or “clean,” building rubble following demolition. However, other disposition options that include the building and/or waste remaining at the NNSS may be considered providing that the same release limits apply. The Final Status Survey was designed following MARSSIM guidance by reviewing historical documentation and radiological survey data. Following this review a formal radiological characterization survey was performed in two phases. The characterization revealed multiple areas of residual radioactivity above the release criteria. These locations were remediated (decontaminated) and then the surface activity was verified to be less than the release criteria. Once remediation efforts had been successfully completed, a Final Status Survey Plan (10-015, “Final Status Survey Plan for Corrective Action Unit 117 – Pluto Disassembly Facility, Building 2201”) was developed and implemented to complete the final step in the MARSSIM process, the Final Status Survey. The Final Status Survey Plan consisted of categorizing each individual room

  3. The maturational disassembly and differential proteolysis of paralogous vitellogenins in a marine pelagophil teleost: a conserved mechanism of oocyte hydration.

    PubMed

    Finn, Roderick Nigel

    2007-06-01

    A structural analysis of the differential proteolysis of vitellogenin (Vtg)-derived yolk proteins in the maturing oocytes of a marine teleost that spawns very large pelagic eggs is presented. Two full-length hepatic cDNAs (hhvtgAa and hhvtgAb) encoding paralogous vitellogenins (HhvtgAa and HhvtgAb) were cloned from nonestrogenized Atlantic halibut, and the N-termini of their subdomain structures were mapped to the oocyte and egg yolk proteins (Yps). The maturational oocyte Yp degradation products were further mapped to the free amino acid (FAA) pool in the ovulated egg. The deduced amino acid sequences conformed to the linear NH(2)-(LvH-Pv-LvL-beta'-CT)-COO(-) structure of complete teleost Vtgs. However, the Yps did not match the expected cleavage products of complete Vtgs. Specifically, the phosvitin subdomain of the HhvtgAa paralogue remains covalently attached to the lipovitellin light chain, while the phosvitin subdomain of the HhvtgAb paralogue remains covalently attached to a C-terminal fragment of the lipovitellin heavy chain (LvH). During oocyte hydration, the LvH of the HhvtgAa paralogue is disassembled and extensively degraded to FAA. In the HhvtgAb paralogue, the LvH is nicked in the C-sheet in a manner similar to that seen in lamprey and other teleosts. A small part of the C-terminal end of the LvH-Ab undergoes proteolysis to FAA, together with the phosvitin, beta' component, and much ( approximately 65%) of the lipovitellin light chain (LvL-Ab). The independently measured FAA pool in the ovulated egg corroborates that calculated from differential proteolysis of the Yps. Based on the 3:1 (HhvtgAb:HhvtgAa) Yp expression ratio, each paralogue contributes approximately equal amounts of FAA to the organic osmolyte pool of the hydrating oocyte during maturation.

  4. PTP1B Dephosphorylates N-Ethylmaleimide-sensitive Factor and Elicits SNARE Complex Disassembly during Human Sperm Exocytosis*

    PubMed Central

    Zarelli, Valeria E. P.; Ruete, Maria C.; Roggero, Carlos M.; Mayorga, Luis S.; Tomes, Claudia N.

    2009-01-01

    The reversible phosphorylation of tyrosyl residues in proteins is a cornerstone of the signaling pathways that regulate numerous cellular responses. Protein tyrosine phosphorylation is controlled through the concerted actions of protein-tyrosine kinases and phosphatases. The goal of the present study was to unveil the mechanisms by which protein tyrosine dephosphorylation modulates secretion. The acrosome reaction, a specialized type of regulated exocytosis undergone by sperm, is initiated by calcium and carried out by a number of players, including tyrosine kinases and phosphatases, and fusion-related proteins such as Rab3A, α-SNAP, N-ethylmaleimide-sensitive factor (NSF), SNAREs, complexin, and synaptotagmin VI. We report here that inducers were unable to elicit the acrosome reaction when permeabilized human sperm were loaded with anti-PTP1B antibodies or with the dominant-negative mutant PTP1B D181A; subsequent introduction of wild type PTP1B or NSF rescued exocytosis. Wild type PTP1B, but not PTP1B D181A, caused cis SNARE complex dissociation during the acrosome reaction through a mechanism involving NSF. Unlike its non-phosphorylated counterpart, recombinant phospho-NSF failed to dissociate SNARE complexes from rat brain membranes. These results strengthen our previous observation that NSF activity is regulated rather than constitutive during sperm exocytosis and indicate that NSF must be dephosphorylated by PTP1B to disassemble SNARE complexes. Interestingly, phospho-NSF served as a substrate for PTP1B in an in vitro assay. Our findings demonstrate that phosphorylation of NSF on tyrosine residues prevents its SNARE complex dissociation activity and establish for the first time a role for PTP1B in the modulation of the membrane fusion machinery. PMID:19208619

  5. Expert System analysis of non-fuel assembly hardware and spent fuel disassembly hardware: Its generation and recommended disposal

    SciTech Connect

    Williamson, D.A.

    1991-12-31

    Almost all of the effort being expended on radioactive waste disposal in the United States is being focused on the disposal of spent Nuclear Fuel, with little consideration for other areas that will have to be disposed of in the same facilities. one area of radioactive waste that has not been addressed adequately because it is considered a secondary part of the waste issue is the disposal of the various Non-Fuel Bearing Components of the reactor core. These hardware components fall somewhat arbitrarily into two categories: Non-Fuel Assembly (NFA) hardware and Spent Fuel Disassembly (SFD) hardware. This work provides a detailed examination of the generation and disposal of NFA hardware and SFD hardware by the nuclear utilities of the United States as it relates to the Civilian Radioactive Waste Management Program. All available sources of data on NFA and SFD hardware are analyzed with particular emphasis given to the Characteristics Data Base developed by Oak Ridge National Laboratory and the characterization work performed by Pacific Northwest Laboratories and Rochester Gas & Electric. An Expert System developed as a portion of this work is used to assist in the prediction of quantities of NFA hardware and SFD hardware that will be generated by the United States` utilities. Finally, the hardware waste management practices of the United Kingdom, France, Germany, Sweden, and Japan are studied for possible application to the disposal of domestic hardware wastes. As a result of this work, a general classification scheme for NFA and SFD hardware was developed. Only NFA and SFD hardware constructed of zircaloy and experiencing a burnup of less than 70,000 MWD/MTIHM and PWR control rods constructed of stainless steel are considered Low-Level Waste. All other hardware is classified as Greater-ThanClass-C waste.

  6. Origin of cratonic basins

    NASA Astrophysics Data System (ADS)

    Dev. Klein, George; Hsui, Albert T.

    1987-12-01

    Tectonic subsidence curves show that the Illinois, Michigan, and Williston basins formed by initial fault-controlled mechanical subsidence during rifting and by subsequent thermal subsidence. Thermal subsidence began around 525 Ma in the Illinois Basin, 520 460 Ma in the Michigan Basin, and 530 500 Ma in the Williston Basin. In the Illinois Basin, a second subsidence episode (middle Mississippian through Early Permian) was caused by flexural foreland subsidence in response to the Alleghanian-Hercynian orogeny. Resurgent Permian rifting in the Illinois Basin is inferred because of intrusion of well-dated Permian alnoites; such intrusive rocks are normally associated with rifting processes. The process of formation of these cratonic basins remains controversial. Past workers have suggested mantle phase changes at the base of the crust, mechanical subsidence in response to isostatically uncompensated excess mass following igneous intrusions, intrusion of mantle plumes into the crust, or regional thermal metamorphic events as causes of basin initiation. Cratonic basins of North America, Europe, Africa, and South America share common ages of formation (around 550 to 500 Ma), histories of sediment accumulation, temporal volume changes of sediment fills, and common dates of interregional unconformities. Their common date of formation suggests initiation of cratonic basins in response to breakup of a late Precambrian super-continent. This supercontinent acted as a heat lens that caused partial melting of the lower crust and upper mantle followed by emplacement of anorogenic granites during extensional tectonics in response to supercontinent breakup. Intrusion of anorogenic granites and other partially melted intrusive rocks weakened continental lithosphere, thus providing a zone of localized regional stretching and permitting formation of cratonic basins almost simultaneously over sites of intrusion of these anorogenic granites and other partially melted intrusive rocks.

  7. K Basin safety analysis

    SciTech Connect

    Porten, D.R.; Crowe, R.D.

    1994-12-16

    The purpose of this accident safety analysis is to document in detail, analyses whose results were reported in summary form in the K Basins Safety Analysis Report WHC-SD-SNF-SAR-001. The safety analysis addressed the potential for release of radioactive and non-radioactive hazardous material located in the K Basins and their supporting facilities. The safety analysis covers the hazards associated with normal K Basin fuel storage and handling operations, fuel encapsulation, sludge encapsulation, and canister clean-up and disposal. After a review of the Criticality Safety Evaluation of the K Basin activities, the following postulated events were evaluated: Crane failure and casks dropped into loadout pit; Design basis earthquake; Hypothetical loss of basin water accident analysis; Combustion of uranium fuel following dryout; Crane failure and cask dropped onto floor of transfer area; Spent ion exchange shipment for burial; Hydrogen deflagration in ion exchange modules and filters; Release of Chlorine; Power availability and reliability; and Ashfall.

  8. Mucin-mediated nanocarrier disassembly for triggered uptake of oligonucleotides as a delivery strategy for the potential treatment of mucosal tumours

    NASA Astrophysics Data System (ADS)

    Martirosyan, A.; Olesen, M. J.; Fenton, R. A.; Kjems, J.; Howard, K. A.

    2016-06-01

    This work demonstrates gastric mucin-triggered nanocarrier disassembly for release of antisense oligonucleotides and consequent unassisted cellular entry as a novel oral delivery strategy. A fluorescence activation-based reporter system was used to investigate the interaction and mucin-mediated disassembly of chitosan-based nanocarriers containing a 13-mer DNA oligonucleotide with a flanked locked RNA nucleic acid gapmer design. Gastric mucins were shown to trigger gapmer release from nanocarriers that was dependent on the interaction time, mucin concentration and N : P ratio with a maximal release at N : P 10. In contrast to siRNA, naked gapmers exhibited uptake into mucus producing HT-MTX mono-cultures and HT-MTX co-cultured with the carcinoma epithelial cell line Caco-2. Importantly, in vivo gapmer uptake was observed in epithelial tissue 30 min post-injection in murine intestinal loops. The findings present a mucosal design-based system tailored for local delivery of oligonucleotides that may maximize the effectiveness of gene silencing therapeutics within tumours at mucosal sites.This work demonstrates gastric mucin-triggered nanocarrier disassembly for release of antisense oligonucleotides and consequent unassisted cellular entry as a novel oral delivery strategy. A fluorescence activation-based reporter system was used to investigate the interaction and mucin-mediated disassembly of chitosan-based nanocarriers containing a 13-mer DNA oligonucleotide with a flanked locked RNA nucleic acid gapmer design. Gastric mucins were shown to trigger gapmer release from nanocarriers that was dependent on the interaction time, mucin concentration and N : P ratio with a maximal release at N : P 10. In contrast to siRNA, naked gapmers exhibited uptake into mucus producing HT-MTX mono-cultures and HT-MTX co-cultured with the carcinoma epithelial cell line Caco-2. Importantly, in vivo gapmer uptake was observed in epithelial tissue 30 min post-injection in murine intestinal

  9. Study to define an approach for developing a computer-based system capable of automatic, unattended assembly/disassembly of spacecraft, phase 1

    NASA Technical Reports Server (NTRS)

    Nevins, J. L.; Defazio, T. L.; Seltzer, D. S.; Whitney, D. E.

    1981-01-01

    The initial set of requirements for additional studies necessary to implement a space-borne, computer-based work system capable of achieving assembly, disassembly, repair, or maintenance in space were developed. The specific functions required of a work system to perform repair and maintenance were discussed. Tasks and relevant technologies were identified and delineated. The interaction of spacecraft design and technology options, including a consideration of the strategic issues of repair versus retrieval-replacement or destruction by removal were considered along with the design tradeoffs for accomplishing each of the options. A concept system design and its accompanying experiment or test plan were discussed.

  10. Authorized Limits for the Release of a 25 Ton Locomotive, Serial Number 21547, at the Area 25 Engine Maintenance, Assembly, and Disassembly Facility, Nevada Test Site, Nevada

    SciTech Connect

    Jeremy Gwin and Douglas Frenette

    2010-04-08

    This document contains process knowledge and radiological data and analysis to support approval for release of the 25-ton locomotive, Serial Number 21547, at the Area 25 Engine Maintenance, Assembly, and Disassembly (EMAD) Facility, located on the Nevada Test Site (NTS). The 25-ton locomotive is a small, one-of-a-kind locomotive used to move railcars in support of the Nuclear Engine for Rocket Vehicle Application project. This locomotive was identified as having significant historical value by the Nevada State Railroad Museum in Boulder City, Nevada, where it will be used as a display piece. A substantial effort to characterize the radiological conditions of the locomotive was undertaken by the NTS Management and Operations Contractor, National Security Technologies, LLC (NSTec). During this characterization process, seven small areas on the locomotive had contamination levels that exceeded the NTS release criteria (limits consistent with U.S. Department of Energy [DOE] Order DOE O 5400.5, “Radiation Protection of the Public and the Environment”). The decision was made to perform radiological decontamination of these known accessible impacted areas to further the release process. On February 9, 2010, NSTec personnel completed decontamination of these seven areas to within the NTS release criteria. Although all accessible areas of the locomotive had been successfully decontaminated to within NTS release criteria, it was plausible that inaccessible areas of the locomotive (i.e., those areas on the locomotive where it was not possible to perform radiological surveys) could potentially have contamination above unrestricted release limits. To access the majority of these inaccessible areas, the locomotive would have to be disassembled. A complete disassembly for a full radiological survey could have permanently destroyed parts and would have ruined the historical value of the locomotive. Complete disassembly would also add an unreasonable financial burden for the

  11. Lockwasher Strongly Resists Disassembly

    NASA Technical Reports Server (NTRS)

    Jeffers, Stephanie Z.

    1991-01-01

    Lockwasher designed to prevent counter-rotation and loosening of machine screw once screw tightened. Tabs engage slots in pawl-and-ratchet fashion. Features similar to those of "childproof" cap on pill bottle. Intended to replace cup-washer-and-screwhead combination exposed to high-speed, turbulent flow in turbomachinery.

  12. Reserves in western basins

    SciTech Connect

    Caldwell, R.H.; Cotton, B.W.

    1995-04-01

    The objective of this project is to investigate the reserves potential of tight gas reservoirs in three Rocky Mountain basins: the Greater Green River (GGRB), Uinta and Piceance basins. The basins contain vast gas resources that have been estimated in the thousands of Tcf hosted in low permeability clastic reservoirs. This study documents the productive characteristics of these tight reservoirs, requantifies gas in place resources, and characterizes the reserves potential of each basin. The purpose of this work is to promote understanding of the resource and to encourage its exploitation by private industry. At this point in time, the GGRB work has been completed and a final report published. Work is well underway in the Uinta and Piceance basins which are being handled concurrently, with reports on these basins being scheduled for the middle of this year. Since the GGRB portion of the project has been completed, this presentation win focus upon that basin. A key conclusion of this study was the subdivision of the resource, based upon economic and technological considerations, into groupings that have distinct properties with regard to potential for future producibility, economics and risk profile.

  13. South American sedimentary basins

    SciTech Connect

    Urien, C.M.

    1984-04-01

    More than 64 sedimentary basins have been identified on the South American continent. According to their regional structural character and tectonic setting, they are classified in 4 super groups. About 20 interior or intracratonic basins occur on South American cratons (Guayanas, Brazilian, and Patagonian). In most cases, their sedimentary fill is Paleozoic or early Mesozoic. Rift or transverse grabens resulting from incipient sea floor spreading extend towards the continental margin. Seventeen basins are located along the Atlantic stable margin, and consist primarily of half grabens with downfaulted seaward blocks. These rifts (or pull-apart basins) were separated as results of the migration of the African and American continental blocks. Therefore the sedimentation is chiefly Cretaceous and Tertiary. On the western edge of South American cratons, almost 20 basins of downwarped blocks extend from Orinoco down to the Malvinas plateau in a relatively uninterrupted chain of retroarc basins, bordered by the Andean orogen. They lie on a flexured Precambrian and Paleozoic basement, and are highly deformed in the west (Subandean belt) due to the action of compressional forces caused by the tectonic influence of the Mesozoic Andean batholith. Westward, the Pacific margin is bordered by 27 foreland and forearc basins, which alternate from north to south on an unstable or quasistable margin, fringed by a trench and slope complex where the ocean crust is subducted beneath the continental plate.

  14. Assessment of the requirements for placing and maintaining Savannah River Site spent fuel storage basins under International Atomic Energy Agency safeguards

    SciTech Connect

    Amacker, O.P. Jr.; Curtis, M.M.; Delegard, C.H.; Hsue, S.T.; Whitesel, R.N.

    1997-03-01

    The United States is considering the offer of irradiated research reactor spent fuel (RRSF) for international safeguards applied by the International Atomic Energy Agency (IAEA). The offer would be to add one or more spent fuel storage basins to the list of facilities eligible for IAEA safeguards. The fuel to be safeguarded would be stored in basins on the Savannah River Site (SRS). This RRSF potentially can include returns of Material Test Reactor (MTR) VAX fuel from Argentina, Brazil, and Chile (ABC); returns from other foreign research reactors; and fuel from domestic research reactors. Basins on the SRS being considered for this fuel storage are the Receiving Basin for Offsite Fuel (RBOF) and the L-Area Disassembly Basin (L-Basin). A working group of SRS, U.S. Department of Energy International Safeguards Division (NN-44), and National Laboratory personnel with experience in IAEA safeguards was convened to consider the requirements for applying the safeguards to this material. The working group projected the safeguards requirements and described alternatives.

  15. Disassembly of Lys11 and Mixed Linkage Polyubiquitin Conjugates Provides Insights into Function of Proteasomal Deubiquitinases Rpn11 and Ubp6*

    PubMed Central

    Mansour, Wissam; Nakasone, Mark A.; von Delbrück, Maximilian; Yu, Zanlin; Krutauz, Daria; Reis, Noa; Kleifeld, Oded; Sommer, Thomas; Fushman, David; Glickman, Michael H.

    2015-01-01

    Protein homeostasis is largely dependent on proteolysis by the ubiquitin-proteasome system. Diverse polyubiquitin modifications are reported to target cellular proteins to the proteasome. At the proteasome, deubiquitination is an essential preprocessing event that contributes to degradation efficiency. We characterized the specificities of two proteasome-associated deubiquitinases (DUBs), Rpn11 and Ubp6, and explored their impact on overall proteasome DUB activity. This was accomplished by constructing a panel of well defined ubiquitin (Ub) conjugates, including homogeneous linkages of varying lengths as well as a heterogeneously modified target. Rpn11 and Ubp6 processed Lys11 and Lys63 linkages with comparable efficiencies that increased with chain length. In contrast, processing of Lys48 linkages by proteasome was inversely correlated to chain length. Fluorescently labeled tetra-Ub chains revealed endo-chain preference for Ubp6 acting on Lys48 and random action for Rpn11. Proteasomes were more efficient at deconjugating identical substrates than their constituent DUBs by roughly 2 orders of magnitude. Incorporation into proteasomes significantly enhanced enzymatic efficiency of Rpn11, due in part to alleviation of the autoinhibitory role of its C terminus. The broad specificity of Rpn11 could explain how proteasomes were more effective at disassembling a heterogeneously modified conjugate compared with homogeneous Lys48-linked chains. The reduced ability to disassemble homogeneous Lys48-linked chains longer than 4 Ub units may prolong residency time on the proteasome. PMID:25389291

  16. Binding-induced autonomous disassembly of aptamer-DNAzyme supersandwich nanostructures for sensitive electrochemiluminescence turn-on detection of ochratoxin A

    NASA Astrophysics Data System (ADS)

    Chen, Ying; Yang, Mengli; Xiang, Yun; Yuan, Ruo; Chai, Yaqin

    2013-12-01

    The self-assembled DNA nanostructure has been one of the most interesting research areas in the field of nanoscience, and the application of the DNA self-assembled nanostructures in biosensing is still in the early stage. In this work, based on the target-induced autonomous disassembly of the aptamer-DNAzyme supersandwich nanostructures, we demonstrated a highly sensitive strategy for electrochemiluminescent (ECL) detection of ochratoxin A (OTA). The aptamer-DNAzyme supersandwich nanostructures, which exhibited significant ECL quenching effect toward the oxygen/persulfate (O2/S2O82-) system, were self-assembled on the gold electrode surface. The presence of the target OTA and the exonuclease (RecJf) resulted in autonomous disassembly of the nanostructures and cyclic reuse of OTA, leading to efficient recovery of the ECL emission and highly sensitive detection of OTA. Our developed method also showed high selectivity against other interference molecules and can be applied for the detection of OTA in real red wine samples, which offers the proposed method opportunities for designing new DNA-based nanostructures for biosensing applications.

  17. Triggered disassembly of hierarchically assembled onion-like micelles into the pristine core-shell micelles via a small change in pH.

    PubMed

    Cai, Guoqiang; Zhang, Haiwen; Liu, Peng; Wang, Liqun; Jiang, Hongliang

    2011-10-01

    The size and surface property of nanomaterial-based delivery systems administered intravenously play important roles in their cell uptake and in vivo distribution. Both of them should be capable of self-evolution in order to achieve efficient targeting performance. A facile strategy was proposed to manipulate both the size and surface property of polymeric micelles. It was found that the hierarchical assembly between trimethylated chitosan-g-poly(ε-caprolactone) (TMC-PCL) micelles and carboxyethyl chitosan-g-poly(ethylene glycol) (CEC-PEG) could produce onion-like micelles with enlarged size and PEGylated surface. The onion-like micelles could withstand the ionic strength of plasma and competitive exchange with BSA, and abruptly disassemble into the pristine TMC-PCL micelles via a small change in pH. By varying the degree of carboxyethylation, the disassembly pH could be modulated to the range of the tumoral microclimate pH. In contrast with TMC-PCL micelles, which displayed high cytotoxicity and endocytic ability towards C6 glioma cells, the onion-like micelles were cell-friendly and internalized by the cells at a very low level. Doxorubicin was used as a model chemotherapeutic agent and incorporated within TMC-PCL micelles. Dox release from both TMC-PCL micelles and the onion-like micelles was very slow under normal physiological conditions and displayed excellent pH sensitivity. Cell viability of Dox-loaded micelles was also investigated.

  18. Assessment of the impacts of spent fuel disassembly alternatives on the Nuclear Waste Isolation System. [Preparing and packaging spent fuel assemblies for geologic disposal

    SciTech Connect

    Not Available

    1984-07-01

    The objective of this report was to evaluate four possible alternative methods of preparing and packaging spent fuel assemblies for geologic disposal against the Reference Process of unmodified spent fuel. The four alternative processes were: (1) End fitting removal, (2) Fission gas venting and resealing, (3) Fuel bundle disassembly and close packing of fuel pins, and (4) Fuel shearing and immobilization. Systems analysis was used to develop a basis of comparison of the alternatives. Conceptual processes and facility layouts were devised for each of the alternatives, based on technology deemed feasible for the purpose. Assessments were made of 15 principal attributes from the technical, operational, safety/risk, and economic considerations related to each of the alternatives, including both the surface packaging and underground repository operations. Specific attributes of the alternative processes were evaluated by assigning a number for each that expressed its merit relative to the corresponding attribute of the Reference Process. Each alternative process was then ranked by summing the numbers for attributes in each of the four assessment areas and collectively. Fuel bundle disassembly and close packing of fuel pins was ranked the preferred method of disposal of spent fuel. 63 references, 46 figures, 46 tables.

  19. Disassembly of amphiphilic small molecular prodrug with fluorescence switch induced by pH and folic acid receptors for targeted delivery and controlled release.

    PubMed

    Xu, Zhigang; Shi, Xiaoxiao; Hou, Meili; Xue, Peng; Gao, Yong-E; Liu, Shiying; Kang, Yuejun

    2017-02-01

    We develop a new type of pH-responsive amphiphilic small molecular prodrug by conjugating folic acid with anti-tumour doxorubicin via a hydrazone bond. This prodrug is featured by high and precise drug loading (55.4wt%), which can self-assemble into micellar nanoparticles in neutral environment while disassemble in the presence of tumour cells expressing folic acid receptors or the acidic tumoral endosomal environment. The prodrug nanoparticles can effectively improve anticancer efficacy due to the features of pH-triggered drug release and targeted delivery. Moreover, in vitro cell study further indicated that the resulting prodrug nanoparticles had enhanced cytotoxicity for folic-acid-positive cells (HeLa) compared to folic-acid-negative cells (MCF-7). More importantly, the induced disassembly of prodrug nanoparticles can "switch on" the inherent fluorescence of the internalized doxorubicin drug in the tumour microenvironment, which can be used for the detection of tumour cells. We believe that this strategy can pave a new way for designing small molecular drug delivery systems and facilitate tumour diagnosis and treatment simultaneously.

  20. Development of an advanced, continuous mild gasification process for the production of co-products. Task 4.8, Decontamination and disassembly of the mild gasification process research unit and disposal of co-products

    SciTech Connect

    Ness, R.O. Jr.; Li, Y.; Heidt, M.

    1992-09-01

    Prior to disassembly of the CFBR, accumulated tar residue must be removed from the reactor, piping and tubing lines, and the condenser vessels. Based on experience from the CFBR mild gasification tests, lacquer thinner must be pumped through the unit for at least one hour to remove the residual tar. The lacquer thinner wash may be followed by a water wash. The CFBR will be disassembled after the system has been thoroughly flushed out. The following equipment must be disassembled and removed for storage: Superheater; Water supply pump; Coal feed system (hopper, auger, ball feeder, valves); Reactor; Cyclone and fines catch pot; Condensers (water lines, glycol bath, condenser pots, valves); and Gas meter. After the process piping and reactor have been disassembled, the equipment will be inspected for tar residues and flushed again with acetone or lacquer thinner, if necessary. All solvent used for cleaning the system will be collected for recycle or proper disposal. Handling and disposal of the solvent will be properly documented. The equipment will be removed and stored for future use. Equipment contaminated externally with tar (Level 4) will be washed piece by piece with lacquer thinner after disassembly of the PRU. Proper health and safety practices must be followed by the personnel involved in the cleanup operation. Care must be taken to avoid ingestion, inhalation, or prolonged skin contact of the coal tars and lacquer thinner. Equipment contaminated internally by accumulation of residual tar or oil (Level 5) will be flushed section by section with lacquer thinner. The equipment will be washed with solvent both before and after disassembly to ensure that all tar has been removed from the piping, pumps, gas quench condensers, light tar condensers, and drain lines. The coal tars wig be separated from the solvent and incinerated.

  1. BASINS Framework and Features

    EPA Pesticide Factsheets

    BASINS enables users to efficiently access nationwide environmental databases and local user-specified datasets, apply assessment and planning tools, and run a variety of proven nonpoint loading and water quality models within a single GIS format.

  2. K Basins Hazard Analysis

    SciTech Connect

    WEBB, R.H.

    1999-12-29

    This report describes the methodology used in conducting the K Basins Hazard Analysis, which provides the foundation for the K Basins Safety Analysis Report (HNF-SD-WM-SAR-062, Rev.4). This hazard analysis was performed in accordance with guidance provided by DOE-STD-3009-94, Preparation Guide for U. S. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports and implements the requirements of DOE Order 5480.23, Nuclear Safety Analysis Report.

  3. K Basin Hazard Analysis

    SciTech Connect

    PECH, S.H.

    2000-08-23

    This report describes the methodology used in conducting the K Basins Hazard Analysis, which provides the foundation for the K Basins Final Safety Analysis Report. This hazard analysis was performed in accordance with guidance provided by DOE-STD-3009-94, Preparation Guide for U. S. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports and implements the requirements of DOE Order 5480.23, Nuclear Safety Analysis Report.

  4. Nam Con Son Basin

    SciTech Connect

    Tin, N.T.; Ty, N.D.; Hung, L.T.

    1994-07-01

    The Nam Con Son basin is the largest oil and gas bearing basin in Vietnam, and has a number of producing fields. The history of studies in the basin can be divided into four periods: Pre-1975, 1976-1980, 1981-1989, and 1990-present. A number of oil companies have carried out geological and geophysical studies and conducted drilling activities in the basin. These include ONGC, Enterprise Oil, BP, Shell, Petro-Canada, IPL, Lasmo, etc. Pre-Tertiary formations comprise quartz diorites, granodiorites, and metamorphic rocks of Mesozoic age. Cenozoic rocks include those of the Cau Formation (Oligocene and older), Dua Formation (lower Miocene), Thong-Mang Cau Formation (middle Miocene), Nam Con Son Formation (upper Miocene) and Bien Dong Formation (Pliocene-Quaternary). The basement is composed of pre-Cenozoic formations. Three fault systems are evident in the basin: north-south fault system, northeast-southwest fault system, and east-west fault system. Four tectonic zones can also be distinguished: western differentiated zone, northern differentiated zone, Dua-Natuna high zone, and eastern trough zone.

  5. Spatial and temporal control of nonmuscle myosin localization: identification of a domain that is necessary for myosin filament disassembly in vivo

    PubMed Central

    1991-01-01

    Myosin null mutants of Dictyostelium are defective for cytokinesis, multicellular development, and capping of surface proteins. We have used these cells as transformation recipients for an altered myosin heavy chain gene that encodes a protein bearing a carboxy-terminal 34- kD truncation. This truncation eliminates threonine phosphorylation sites previously shown to control filament assembly in vitro. Despite restoration of growth in suspension, development, and ability to cap cell surface proteins, these delta C34-truncated myosin transformants display severe cytoskeletal abnormalities, including excessive localization of the truncated myosin to the cortical cytoskeleton, impaired cell shaped dynamics, and a temporal defect in myosin dissociation from beneath capped surface proteins. These data demonstrate that the carboxy-terminal domain of myosin plays a critical role in regulating the disassembly of the protein from contractile structures in vivo. PMID:1899668

  6. Effect of medium dependent binding energies on inferring the temperatures and freeze-out density of disassembling hot nuclear matter from cluster yields

    NASA Astrophysics Data System (ADS)

    Shlomo, S.; Röpke, G.; Natowitz, J. B.; Qin, L.; Hagel, K.; Wada, R.; Bonasera, A.

    2009-03-01

    We explore the abundance of light clusters in asymmetric nuclear matter at subsaturation density. With increasing density, binding energies and wave functions are modified due to medium effects. The method of Albergo, Costa, Costanzo, and Rubbino (ACCR) for determining the temperature and free nucleon density of a disassembling hot nuclear source from fragment yields is modified to include, in addition to Coulomb effects and flow, also effects of medium modifications of cluster properties, which become of importance when the nuclear matter density is above 10-3fm-3. We show how the analysis of cluster yields, to infer temperature and nucleon densities, is modified if the shifts in binding energies of in medium clusters are included. Although, at low densities, the temperature calculated from given yields changes only modestly if medium effects are taken into account, larger discrepancies are observed when the nucleon densities are determined from measured yields.

  7. Streamlined Approach for Environmental Restoration Plan for Corrective Action Unit 113: Reactor Maintenance, Assembly, and Disassembly Building Nevada Test Site, Nevada

    SciTech Connect

    J. L. Smith

    2001-01-01

    This Streamlined Approach for Environmental Restoration (SAFER) Plan addresses the action necessary for the closure in place of Corrective Action Unit (CAU) 113 Area 25 Reactor Maintenance, Assembly, and Disassembly Facility (R-MAD). CAU 113 is currently listed in Appendix III of the Federal Facility Agreement and Consent Order (FFACO) (NDEP, 1996). The CAU is located in Area 25 of the Nevada Test Site (NTS) and consists of Corrective Action Site (CAS) 25-04-01, R-MAD Facility (Figures 1-2). This plan provides the methodology for closure in place of CAU 113. The site contains radiologically impacted and hazardous material. Based on preassessment field work, there is sufficient process knowledge to close in place CAU 113 using the SAFER process. At a future date when funding becomes available, the R-MAD Building (25-3110) will be demolished and inaccessible radiologic waste will be properly disposed in the Area 3 Radiological Waste Management Site (RWMS).

  8. River basin management

    SciTech Connect

    Newsome, D.H.; Edwards, A.M.C.

    1984-01-01

    The quality of water is of paramount importance in the management of water resources - including marine waters. A quantitative knowledge of water quality and the factors governing it is required to formulate and implement strategies requiring an inter-disciplinary approach. The overall purpose of this conference was to bring together the latest work on water quality aspects of river basin management. These proceedings are structured on the basis of five themes: problems in international river basins; the contribution of river systems to estuarial and marine pollution; the setting of standards; monitoring; and practical water quality management including use of mathematical models. They are followed by papers from the workshop on advances in the application of mathematical modelling to water quality management, which represent some of the current thinking on the problems and concepts of river basin management.

  9. Delaware River Basin

    USGS Publications Warehouse

    Fischer, Jeffrey M.

    1999-01-01

    Assessing the quality of water in every location of the Nation would not be practical. Therefore, NAWQA investigations are conducted within 59 selected areas called study units (fig. 1). These study units encompass important river and aquifer systems in the United States and represent the diverse geographic, waterresource, land-use, and water-use characteristics of the Nation. The Delaware River Basin is one of 15 study units in which work began in 1996. Water-quality sampling in the study unit will begin in 1999. This fact sheet provides a brief overview of the NAWQA program, describes the Delaware River Basin study unit, identifies the major water-quality issues in the basin, and documents the plan of study that will be followed during the study-unit investigation.

  10. The activity of the histone chaperone yeast Asf1 in the assembly and disassembly of histone H3/H4–DNA complexes

    PubMed Central

    Donham, Douglas C.; Scorgie, Jean K.; Churchill, Mair E. A.

    2011-01-01

    The deposition of the histones H3/H4 onto DNA to give the tetrasome intermediate and the displacement of H3/H4 from DNA are thought to be the first and the last steps in nucleosome assembly and disassembly, respectively. Anti-silencing function 1 (Asf1) is a chaperone of the H3/H4 dimer that functions in both of these processes. However, little is known about the thermodynamics of chaperone–histone interactions or the direct role of Asf1 in the formation or disassembly of histone–DNA complexes. Here, we show that Saccharomyces cerevisiae Asf1 shields H3/H4 from unfavorable DNA interactions and aids the formation of favorable histone–DNA interactions through the formation of disomes. However, Asf1 was unable to disengage histones from DNA for tetrasomes formed with H3/H4 and strong nucleosome positioning DNA sequences or tetrasomes weakened by mutant (H3K56Q/H4) histones or non-positioning DNA sequences. Furthermore, Asf1 did not associate with preformed tetrasomes. These results are consistent with the measured affinity of Asf1 for H3/H4 dimers of 2.5 nM, which is weaker than the association of H3/H4 for DNA. These studies support a mechanism by which Asf1 aids H3/H4 deposition onto DNA but suggest that additional factors or post-translational modifications are required for Asf1 to remove H3/H4 from tetrasome intermediates in chromatin. PMID:21447559

  11. Breast Cancer Antiestrogen Resistance 3 (BCAR3) – p130Cas Interactions Promote Adhesion Disassembly and Invasion in Breast Cancer Cells

    PubMed Central

    Cross, Allison M.; Wilson, Ashley L.; Guerrero, Michael S.; Thomas, Keena S.; Bachir, Alexia I.; Kubow, Kristopher E.; Horwitz, A. Rick; Bouton, Amy H.

    2016-01-01

    Adhesion turnover is critical for cell motility and invasion. We previously demonstrated that the adaptor molecule Breast Cancer Antiestrogen Resistance 3 (BCAR3) promotes adhesion disassembly and breast tumor cell invasion. One of two established binding partners of BCAR3 is the adaptor molecule, p130Cas. In this study, we sought to determine whether signaling through the BCAR3/Cas complex was responsible for the cellular functions of BCAR3. We show that the entire pool of BCAR3 is in complex with Cas in invasive breast tumor cells and that these proteins co-localize in dynamic cellular adhesions. While accumulation of BCAR3 in adhesions did not require Cas binding, a direct interaction between BCAR3 and Cas was necessary for efficient dissociation of BCAR3 from adhesions. The dissociation rates of Cas and two other adhesion molecules, α-actinin and talin, were also significantly slower in the presence of a Cas-binding mutant of BCAR3, suggesting that turnover of the entire adhesion complex was delayed under these conditions. As was the case for adhesion turnover, BCAR3-Cas interactions were found to be important for BCAR3-mediated breast tumor cell chemotaxis toward serum and invasion in Matrigel. Previous work demonstrated that BCAR3 is a potent activator of Rac1, which in turn is an important regulator of adhesion dynamics and invasion. However, in contrast to wildtype BCAR3, ectopic expression of the Cas-binding mutant of BCAR3 failed to induce Rac1 activity in breast cancer cells. Together, these data show that the ability of BCAR3 to promote adhesion disassembly, tumor cell migration and invasion, and Rac1 activity is dependent on its ability to bind to Cas. The activity of BCAR3-Cas complexes as a functional unit in breast cancer is further supported by the co-expression of these molecules in multiple subtypes of human breast tumors. PMID:27109104

  12. BASINS Climate Assessment Tool Tutorials

    EPA Pesticide Factsheets

    The BASINS Climate Assessment Tool (CAT) provides a flexible set of capabilities for exploring the potential effects of climate change on streamflow and water quality using different watershed models in BASINS.

  13. BASINS User Information and Guidance

    EPA Pesticide Factsheets

    This page provides links to guidance on how to use BASINS, including the User’s Manual, tutorials and training, technical notes, case studies, and publications that highlight the use of BASINS in various watershed analyses.

  14. Taunton River basin

    USGS Publications Warehouse

    Williams, John R.; Willey, Richard E.

    1970-01-01

    This report presents in tabular form selected records of wells, test wells, and borings collected during a study of the basin from 1966 to 1968 in cooperation with the Massachusetts Water Resources Commission, and during earlier studies. This report is released in order to make available to the public and to local, state, and federal agencies basic ground-water information that may aid in planning water-resources development. Basic records contained in this report will complement an interpretative report on the Taunton River basin to be released at a later date.

  15. America's Caribbean Basin Initiative.

    ERIC Educational Resources Information Center

    Kasten, Robert W.

    1983-01-01

    Nearly all of the countries that have succeeded in their development over the past 30 years have done so on the strength of market-oriented policies and vigorous participation in the international economy. Aid must be complemented by trade and investment. The Caribbean Basin Initiative puts these principles into practice. (RM)

  16. Natural frequency of regular basins

    NASA Astrophysics Data System (ADS)

    Tjandra, Sugih S.; Pudjaprasetya, S. R.

    2014-03-01

    Similar to the vibration of a guitar string or an elastic membrane, water waves in an enclosed basin undergo standing oscillatory waves, also known as seiches. The resonant (eigen) periods of seiches are determined by water depth and geometry of the basin. For regular basins, explicit formulas are available. Resonance occurs when the dominant frequency of external force matches the eigen frequency of the basin. In this paper, we implement the conservative finite volume scheme to 2D shallow water equation to simulate resonance in closed basins. Further, we would like to use this scheme and utilizing energy spectra of the recorded signal to extract resonant periods of arbitrary basins. But here we first test the procedure for getting resonant periods of a square closed basin. The numerical resonant periods that we obtain are comparable with those from analytical formulas.

  17. Buried-euxenic-basin model sets Tarim basin potential

    SciTech Connect

    Hsu, K.J. )

    1994-11-28

    The Tarim basin is the largest of the three large sedimentary basins of Northwest China. The North and Southwest depressions of Tarim are underlain by thick sediments and very thin crust. The maximum sediment thickness is more than 15 km. Of the several oil fields of Tarim, the three major fields were discovered during the last decade, on the north flank of the North depression and on the Central Tarim Uplift. The major targets of Tarim, according to the buried-euxenic-basin model, should be upper Paleozoic and lower Mesozoic reservoirs trapping oil and gas condensates from lower Paleozoic source beds. The paper describes the basin and gives a historical perspective of exploration activities and discoveries. It then explains how this basin can be interpreted by the buried-euxenic-basin model. The buried-euxenic-basin model postulates four stages of geologic evolution: (1) Sinian and early Paleozoic platform sedimentation on relic arcs and deep-marine sedimentation in back-arc basins in Xinjiang; (2) Late Paleozoic foreland-basin sedimentation in north Tarim; (3) Mesozoic and Paleogene continental deposition, subsidence under sedimentary load; and (4) Neogene pull-apart basin, wrench faulting and extension.

  18. Canada Basin revealed

    USGS Publications Warehouse

    Mosher, David C.; Shimeld, John; Hutchinson, Deborah R.; Chian, D; Lebedeva-Ivanova, Nina; Jackson, Ruth

    2012-01-01

    More than 15,000 line-km of new regional seismic reflection and refraction data in the western Arctic Ocean provide insights into the tectonic and sedimentologic history of Canada Basin, permitting development of new geologic understanding in one of Earth's last frontiers. These new data support a rotational opening model for southern Canada Basin. There is a central basement ridge possibly representing an extinct spreading center with oceanic crustal velocities and blocky basement morphology characteristic of spreading centre crust surrounding this ridge. Basement elevation is lower in the south, mostly due to sediment loading subsidence. The sedimentary succession is thickest in the southern Beaufort Sea region, reaching more than 15 km, and generally thins to the north and west. In the north, grabens and half-grabens are indicative of extension. Alpha-Mendeleev Ridge is a large igneous province in northern Amerasia Basin, presumably emplaced synchronously with basin formation. It overprints most of northern Canada Basin structure. The seafloor and sedimentary succession of Canada Basin is remarkably flat-lying in its central region, with little bathymetric change over most of its extent. Reflections that correlate over 100s of kms comprise most of the succession and on-lap bathymetric and basement highs. They are interpreted as representing deposits from unconfined turbidity current flows. Sediment distribution patterns reflect changing source directions during the basin’s history. Initially, probably late Cretaceous to Paleocene synrift sediments sourced from the Alaska and Mackenzie-Beaufort margins. This unit shows a progressive series of onlap unconformities with a younging trend towards Alpha and Northwind ridges, likely a response to contemporaneous subsidence. Sediment source direction appeared to shift to the Canadian Arctic Archipelago margin for the Eocene and Oligocene, likely due to uplift of Arctic islands during the Eurekan Orogeny. The final

  19. Dimension of fractal basin boundaries

    SciTech Connect

    Park, B.S.

    1988-01-01

    In many dynamical systems, multiple attractors coexist for certain parameter ranges. The set of initial conditions that asymptotically approach each attractor is its basin of attraction. These basins can be intertwined on arbitrary small scales. Basin boundary can be either smooth or fractal. Dynamical systems that have fractal basin boundary show final state sensitivity of the initial conditions. A measure of this sensitivity (uncertainty exponent {alpha}) is related to the dimension of the basin boundary d = D - {alpha}, where D is the dimension of the phase space and d is the dimension of the basin boundary. At metamorphosis values of the parameter, there might happen a conversion from smooth to fractal basin boundary (smooth-fractal metamorphosis) or a conversion from fractal to another fractal basin boundary characteristically different from the previous fractal one (fractal-fractal metamorphosis). The dimension changes continuously with the parameter except at the metamorphosis values where the dimension of the basin boundary jumps discontinuously. We chose the Henon map and the forced damped pendulum to investigate this. Scaling of the basin volumes near the metamorphosis values of the parameter is also being studied for the Henon map. Observations are explained analytically by using low dimensional model map.

  20. Albuquerque Basin seismic network

    USGS Publications Warehouse

    Jaksha, Lawrence H.; Locke, Jerry; Thompson, J.B.; Garcia, Alvin

    1977-01-01

    The U.S. Geological Survey has recently completed the installation of a seismic network around the Albuquerque Basin in New Mexico. The network consists of two seismometer arrays, a thirteen-station array monitoring an area of approximately 28,000 km 2 and an eight-element array monitoring the area immediately adjacent to the Albuquerque Seismological Laboratory. This report describes the instrumentation deployed in the network.

  1. Great Basin Paleontological Bibliography

    USGS Publications Warehouse

    Blodgett, Robert B.; Zhang, Ning; Hofstra, Albert H.; Morrow, Jared R.

    2007-01-01

    Introduction This work was conceived as a derivative product for 'The Metallogeny of the Great Basin' project of the Mineral Resources Program of the U.S. Geological Survey. In the course of preparing a fossil database for the Great Basin that could be accessed from the Internet, it was determined that a comprehensive paleontological bibliography must first be compiled, something that had not previously been done. This bibliography includes published papers and abstracts as well as unpublished theses and dissertations on fossils and stratigraphy in Nevada and adjoining portions of California and Utah. This bibliography is broken into first-order headings by geologic age, secondary headings by taxonomic group, followed by ancillary topics of interest to both paleontologists and stratigraphers; paleoecology, stratigraphy, sedimentary petrology, paleogeography, tectonics, and petroleum potential. References were derived from usage of Georef, consultation with numerous paleontologists and geologists working in the Great Basin, and literature currently on hand with the authors. As this is a Web-accessible bibliography, we hope to periodically update it with new citations or older references that we have missed during this compilation. Hence, the authors would be grateful to receive notice of any new or old papers that the readers think should be added. As a final note, we gratefully acknowledge the helpful reviews provided by A. Elizabeth J. Crafford (Anchorage, Alaska) and William R. Page (USGS, Denver, Colorado).

  2. Advanced Chemistry Basins Model

    SciTech Connect

    William Goddard; Mario Blanco; Lawrence Cathles; Paul Manhardt; Peter Meulbroek; Yongchun Tang

    2002-11-10

    The DOE-funded Advanced Chemistry Basin model project is intended to develop a public domain, user-friendly basin modeling software under PC or low end workstation environment that predicts hydrocarbon generation, expulsion, migration and chemistry. The main features of the software are that it will: (1) afford users the most flexible way to choose or enter kinetic parameters for different maturity indicators; (2) afford users the most flexible way to choose or enter compositional kinetic parameters to predict hydrocarbon composition (e.g., gas/oil ratio (GOR), wax content, API gravity, etc.) at different kerogen maturities; (3) calculate the chemistry, fluxes and physical properties of all hydrocarbon phases (gas, liquid and solid) along the primary and secondary migration pathways of the basin and predict the location and intensity of phase fractionation, mixing, gas washing, etc.; and (4) predict the location and intensity of de-asphaltene processes. The project has be operative for 36 months, and is on schedule for a successful completion at the end of FY 2003.

  3. Caribbean basin framework, 3: Southern Central America and Colombian basin

    SciTech Connect

    Kolarsky, R.A.; Mann, P. )

    1991-03-01

    The authors recognize three basin-forming periods in southern Central America (Panama, Costa Rica, southern Nicaragua) that they attempt to correlate with events in the Colombian basin (Bowland, 1984): (1) Early-Late Cretaceous island arc formation and growth of the Central American island arc and Late Cretaceous formation of the Colombian basin oceanic plateau. During latest Cretaceous time, pelagic carbonate sediments blanketed the Central American island arc in Panama and Costa Rica and elevated blocks on the Colombian basin oceanic plateau; (2) middle Eocene-middle Miocene island arc uplift and erosion. During this interval, influx of distal terrigenous turbidites in most areas of Panama, Costa Rica, and the Colombian basin marks the uplift and erosion of the Central American island arc. In the Colombian basin, turbidites fill in basement relief and accumulate to thicknesses up to 2 km in the deepest part of the basin. In Costa Rica, sedimentation was concentrated in fore-arc (Terraba) and back-arc (El Limon) basins; (3) late Miocene-Recent accelerated uplift and erosion of segments of the Central American arc. Influx of proximal terrigenous turbidites and alluvial fans in most areas of Panama, Costa Rica, and the Colombian basin marks collision of the Panama arc with the South American continent (late Miocene early Pliocene) and collision of the Cocos Ridge with the Costa Rican arc (late Pleistocene). The Cocos Ridge collision inverted the Terraba and El Limon basins. The Panama arc collision produced northeast-striking left-lateral strike-slip faults and fault-related basins throughout Panama as Panama moved northwest over the Colombian basin.

  4. Seismic exploration in Raton basin

    SciTech Connect

    Applegate, J.K.; Rose, P.R.

    1985-05-01

    Exploration in the Raton basin has delineated complex mountain-front structure in the asymmetric basin, and defined possible basin-centered gas. Exploration has included subsurface and surface geology, remote sensing, and seismic reflection. The Raton basin is a north-south-trending structural basin straddling the Colorado-New Mexico boundary. It is bounded on the west by the Sangre de Cristo Mountains, on the north and northeast by the Wet Mountains and Apishapa arch, and the Sierra Grande uplift on the south and southeast. The basin is asymmetric with transcurrent faulting and thrusting associated with the steeper western flank of the basin. Rocks range from Devonian-Mississippian overlying Precambrian basement to Miocene volcanics associated with the Spanish Peaks. Principal targets include the Entrada, Dakota, Codell, and Trinidad Sandstones and the Purgatoire and Raton Formations. Seismic data include explosive and Vibroseis data. Data quality is good in the basin center and is fair in the thrusted areas. Correlations are difficult from line to line. However, a strike line in the disturbed area would probably be more disrupted by out-of-the-plane reflections than the dip lines would be. Significant stratigraphic changes are seen in both the Trinidad and Dakota intervals. Integrated seismic and geological studies are keys to exploration in the basin. Subsequent work will rely heavily on improved seismic information.

  5. Results of brine flow testing and disassembly of a crushed salt/bentonite block seal at the Waste Isolation Pilot Plant

    SciTech Connect

    Finley, R.E.; Jones, R.L.

    1994-03-01

    The Small-Scale Seal Performance Tests, Series C, a set of in situ experiments conducted at the Waste Isolation Pilot Plant, are designed to evaluate the performance of various seal materials emplaced in large (0.9-m-diameter) boreholes. This report documents the results of fluid (brine) flow testing and water and clay content analyses performed on one emplaced seal comprised of 100% salt blocks and 50%/50% crushed salt/bentonite blocks and disassembled after nearly three years of brine injection testing. Results from the water content analyses of 212 samples taken from within this seal show uniform water content throughout the 50%/50% salt/bentonite blocks with saturations about 100%. Clay content analyses from the 100% salt endcaps of the seal show a background clay content of about 1% by weight uniformly distributed, with the exception of samples taken at the base of the seal at the borehole wall interface. These samples show clay contents up to 3% by weight, which suggests some bentonite may have migrated under pressure to that interface. Results of the brine-flow testing show that the permeability to brine for this seal was about 2 to 3 {times} 10{sup {minus}4} darcy (2 to 3 {times} 10{sup {minus}16} m{sup 2}).

  6. Telomere targeting with a novel G-quadruplex-interactive ligand BRACO-19 induces T-loop disassembly and telomerase displacement in human glioblastoma cells

    PubMed Central

    Zhou, Guangtong; Liu, Xinrui; Li, Yunqian; Xu, Songbai; Ma, Chengyuan; Wu, Xinmin; Cheng, Ye; Yu, Zhiyun; Zhao, Gang; Chen, Yong

    2016-01-01

    Interference with telomerase and telomere maintenance is emerging as an attractive target for anticancer therapies. Ligand-induced stabilization of G-quadruplex formation by the telomeric DNA 3′-overhang inhibits telomerase from catalyzing telomeric DNA synthesis and from capping telomeric ends, making these ligands good candidates for chemotherapeutic purposes. BRACO-19 is one of the most effective and specific ligand for telomeric G4. It is shown here that BRACO-19 suppresses proliferation and reduces telomerase activity in human glioblastoma cells, paralleled by the displacement of telomerase from nuclear to cytoplasm. Meanwhile, BRACO-19 triggers extensive DNA damage response at telomere, which may result from uncapping and disassembly of telomeric T-loop structure, characterized by the formation of anaphase bridge and telomere fusion, as well as the release of telomere-binding protein from telomere. The resulting dysfunctional telomere ultimately provokes p53 and p21-mediated cell cycle arrest, apoptosis and senescence. Notably, normal primary astrocytes do not respond to the treatment of BRACO-19, suggesting the agent's good selectivity for cancer cells. These results reinforce the notion that G-quadruplex binding compounds can act as broad inhibitors of telomere-related processes and have potential as selective antineoplastic drugs for various tumors including malignant gliomas. PMID:26908447

  7. Rab5 GTPase controls chromosome alignment through Lamin disassembly and relocation of the NuMA-like protein Mud to the poles during mitosis

    PubMed Central

    Capalbo, Luisa; D'Avino, Pier Paolo; Archambault, Vincent; Glover, David M.

    2011-01-01

    The small GTPase Rab5 is a conserved regulator of membrane trafficking; it regulates the formation of early endosomes, their transport along microtubules, and the fusion to the target organelles. Although several members of the endocytic pathway were recently implicated in spindle organization, it is unclear whether Rab5 has any role during mitosis. Here, we describe that Rab5 is required for proper chromosome alignment during Drosophila mitoses. We also found that Rab5 associated in vivo with nuclear Lamin and mushroom body defect (Mud), the Drosophila counterpart of nuclear mitotic apparatus protein (NuMA). Consistent with this finding, Rab5 was required for the disassembly of the nuclear envelope at mitotic entry and the accumulation of Mud at the spindle poles. Furthermore, Mud depletion caused chromosome misalignment defects that resembled the defects of Rab5 RNAi cells, and double-knockdown experiments indicated that the two proteins function in a linear pathway. Our results indicate a role for Rab5 in mitosis and reinforce the emerging view of the contributions made by cell membrane dynamics to spindle function. PMID:21987826

  8. Protein dynamics of human RPA and RAD51 on ssDNA during assembly and disassembly of the RAD51 filament

    PubMed Central

    Ma, Chu Jian; Gibb, Bryan; Kwon, YoungHo; Sung, Patrick; Greene, Eric C.

    2017-01-01

    Homologous recombination (HR) is a crucial pathway for double-stranded DNA break (DSB) repair. During the early stages of HR, the newly generated DSB ends are processed to yield long single-stranded DNA (ssDNA) overhangs, which are quickly bound by replication protein A (RPA). RPA is then replaced by the DNA recombinase Rad51, which forms extended helical filaments on the ssDNA. The resulting nucleoprotein filament, known as the presynaptic complex, is responsible for pairing the ssDNA with homologous double-stranded DNA (dsDNA), which serves as the template to guide DSB repair. Here, we use single-molecule imaging to visualize the interplay between human RPA (hRPA) and human RAD51 during presynaptic complex assembly and disassembly. We demonstrate that ssDNA-bound hRPA can undergo facilitated exchange, enabling hRPA to undergo rapid exchange between free and ssDNA-bound states only when free hRPA is present in solution. Our results also indicate that the presence of free hRPA inhibits RAD51 filament nucleation, but has a lesser impact upon filament elongation. This finding suggests that hRPA exerts important regulatory influence over RAD51 and may in turn affect the properties of the assembled RAD51 filament. These experiments provide an important basis for further investigations into the regulation of human presynaptic complex assembly. PMID:27903895

  9. S6K1-mediated disassembly of mitochondrial URI/PP1gamma complexes activates a negative feedback program that counters S6K1 survival signaling.

    PubMed

    Djouder, Nabil; Metzler, Stefan Christian; Schmidt, Alexander; Wirbelauer, Christiane; Gstaiger, Matthias; Aebersold, Ruedi; Hess, Daniel; Krek, Wilhelm

    2007-10-12

    S6 kinase 1 (S6K1) acts to integrate nutrient and growth factor signals to promote cell growth but also cell survival as a mitochondria-tethered protein kinase that phosphorylates and inactivates the proapoptotic molecule BAD. Here we report that the prefoldin chaperone URI represents a mitochondrial substrate of S6K1. In growth factor-deprived or rapamycin-treated cells, URI forms stable complexes with protein phosphatase (PP)1gamma at mitochondria, thereby inhibiting the activity of the bound enzyme. Growth factor stimulation induces disassembly of URI/PP1gamma complexes through S6K1-mediated phosphorylation of URI at serine 371. This activates a PP1gamma-dependent negative feedback program that decreases S6K1 activity and BAD phosphorylation, thereby altering the threshold for apoptosis. These findings establish URI and PP1gamma as integral components of an S6K1-regulated mitochondrial pathway dedicated, in part, to oppose sustained S6K1 survival signaling and to ensure that the mitochondrial threshold for apoptosis is set in accord with nutrient and growth factor availability.

  10. Amino acids substitutions in σ1 and μ1 outer capsid proteins of a Vero cell-adapted mammalian orthoreovirus are required for optimal virus binding and disassembly.

    PubMed

    Sandekian, Véronique; Lemay, Guy

    2015-01-22

    In a recent study, the serotype 3 Dearing strain of mammalian orthoreovirus was adapted to Vero cells; cells that exhibit a limited ability to support the early steps of reovirus uncoating and are unable to produce interferon as an antiviral response upon infection. The Vero cell-adapted virus (VeroAV) exhibits amino acids substitutions in both the σ1 and μ1 outer capsid proteins but no changes in the σ3 protein. Accordingly, the virus was shown not to behave as a classical uncoating mutant. In the present study, an increased ability of the virus to bind at the Vero cell surface was observed and is likely associated with an increased ability to bind onto cell-surface sialic acid residues. In addition, the kinetics of μ1 disassembly from the virions appears to be altered. The plasmid-based reverse genetics approach confirmed the importance of σ1 amino acids substitutions in VeroAV's ability to efficiently infect Vero cells, although μ1 co-adaptation appears necessary to optimize viral infection. This approach of combining in vitro selection of reoviruses with reverse genetics to identify pertinent amino acids substitutions appears promising in the context of eventual reovirus modification to increase its potential as an oncolytic virus.

  11. A crucial role for β2 integrins in podosome formation, dynamics and Toll-like-receptor-signaled disassembly in dendritic cells

    PubMed Central

    Gawden-Bone, Christian; West, Michele A.; Morrison, Vicky L.; Edgar, Alexander J.; McMillan, Sarah J.; Dill, Brian D.; Trost, Matthias; Prescott, Alan; Fagerholm, Susanna C.; Watts, Colin

    2014-01-01

    ABSTRACT The dynamic properties of podosomes, their ability to degrade the underlying matrix and their modulation by Toll-like receptor (TLR) signaling in dendritic cells (DCs) suggests they have an important role in migration. Integrins are thought to participate in formation and dynamics of podosomes but the multiplicity of integrins in podosomes has made this difficult to assess. We report that murine DCs that lack β2 integrins fail to form podosomes. Re-expression of β2 integrins restored podosomes but not when the membrane proximal or distal NPxF motifs, or when an intervening triplet of threonine residues were mutated. We show that β2 integrins are remarkably long-lived in podosome clusters and form a persistent framework that hosts multiple actin-core-formation events at the same or adjacent sites. When β2 integrin amino acid residues 745 or 756 were mutated from Ser to Ala, podosomes became resistant to dissolution mediated through TLR signaling. TLR signaling did not detectably modulate phosphorylation at these sites but mutation of either residue to phospho-mimetic Asp increased β2 integrin turnover in podosomes, indicating that phosphorylation at one or both sites establishes permissive conditions for TLR-signaled podosome disassembly. PMID:25086067

  12. Id-1 promotes TGF-{beta}1-induced cell motility through HSP27 activation and disassembly of adherens junction in prostate epithelial cells

    SciTech Connect

    Di Kaijun; Wong, Y.C. Wang Xianghong

    2007-11-15

    Id-1 (inhibitor of differentiation or DNA binding-1) has been positively associated with cell proliferation, cell cycle progression, and invasiveness during tumorigenesis. In addition, Id-1 has been shown to modulate cellular sensitivity to TGF-{beta}1 (transforming growth factor {beta}1). Here we demonstrate a novel role of Id-1 in promoting TGF-{beta}1-induced cell motility in a non-malignant prostate epithelial cell line, NPTX. We found that Id-1 promoted F-actin stress fiber formation in response to TGF-{beta}1, which was associated with increased cell-substrate adhesion and cell migration in NPTX cells. In addition, this positive effect of Id-1 on TGF-{beta}1-induced cell motility was mediated through activation of MEK-ERK signaling pathway and subsequent phosphorylation of HSP27 (heat shock protein 27). Furthermore, Id-1 disrupted the adherens junction complex in TGF-{beta}1-treated cells through down-regulation of E-cadherin, redistribution of {beta}-catenin, along with up-regulation of N-cadherin. These lines of evidence reveal a novel tumorigenic role of Id-1 through reorganization of actin cytoskeleton and disassembly of cell-cell adhesion in response to TGF-{beta}1 in human prostate epithelial cells, and suggest that intracellular Id-1 levels might be a determining factor for switching TGF-{beta}1 from a growth inhibitor to a tumor promoter during prostate carcinogenesis.

  13. Venezuela Basin crustal structure

    NASA Astrophysics Data System (ADS)

    Diebold, J. B.; Stoffa, P. L.; Buhl, P.; Truchan, M.

    1981-09-01

    Velocity-depth profiles derived from six two-ship expanding spread experiments, in combination with other geophysical data, define the characteristics of two distinct types of Venezuela Basin crust and the boundary between them. Each two-ship common midpoint reflection/refraction profile is automatically transformed into the τ-p plane, `picked' and interpreted to provide V(Z) functions with appropriate confidence bounds. The results, together with gravity, magnetic, and near-vertical incidence reflection data, reveal a 50,000 km2 triangle of Venezuela Basin crust which resembles normal oceanic crust in a magnetic quiet zone. North and west of this triangle lies the previously defined, thick `Caribbean' crust, having two distinct layers above the M discontinuity. Acoustic basement there appears unusually smooth due to extensive basaltic sills and flows which were cored at Deep Sea Drilling Project sites 146/149(sills), and 150 (flows); also, depths to mantle are greater than normal. Interpretations of near-vertical and wide-angle reflection data show that the extra crustal thickness is due not only to the emplacement of the flows but also to the crust below being somewhat thicker than normal. The boundary between the two crustal areas has a NE-SW trend which parallels the dominant structural and magnetic lineations.This boundary coincides in position, though not in trend, with the previously defined `central Venezuela Basin fault zone'. Further study is required to determine whether this boundary is of tectonic origin or if it represents a change in style of crustal production.

  14. Great Basin paleontological database

    USGS Publications Warehouse

    Zhang, N.; Blodgett, R.B.; Hofstra, A.H.

    2008-01-01

    The U.S. Geological Survey has constructed a paleontological database for the Great Basin physiographic province that can be served over the World Wide Web for data entry, queries, displays, and retrievals. It is similar to the web-database solution that we constructed for Alaskan paleontological data (www.alaskafossil.org). The first phase of this effort was to compile a paleontological bibliography for Nevada and portions of adjacent states in the Great Basin that has recently been completed. In addition, we are also compiling paleontological reports (Known as E&R reports) of the U.S. Geological Survey, which are another extensive source of l,egacy data for this region. Initial population of the database benefited from a recently published conodont data set and is otherwise focused on Devonian and Mississippian localities because strata of this age host important sedimentary exhalative (sedex) Au, Zn, and barite resources and enormons Carlin-type An deposits. In addition, these strata are the most important petroleum source rocks in the region, and record the transition from extension to contraction associated with the Antler orogeny, the Alamo meteorite impact, and biotic crises associated with global oceanic anoxic events. The finished product will provide an invaluable tool for future geologic mapping, paleontological research, and mineral resource investigations in the Great Basin, making paleontological data acquired over nearly the past 150 yr readily available over the World Wide Web. A description of the structure of the database and the web interface developed for this effort are provided herein. This database is being used ws a model for a National Paleontological Database (which we am currently developing for the U.S. Geological Survey) as well as for other paleontological databases now being developed in other parts of the globe. ?? 2008 Geological Society of America.

  15. Hydrocarbon associations in evaporite basins

    SciTech Connect

    Warren, J.

    1988-01-01

    Evaporite deposition today is not representative of the diversity of scale of evaporites of the past. Ancient evaporites were deposited in two main settings: platform wide or basin wide. Platform evaporites were composed of relatively thin stratiform units (usually <5-10 m thick) deposited on either ramps or behind rimmed shelves. Basinal evaporites were deposited as thick bedded units 10s to 100s of m thick, and laid down in 4 main tectonic settings--rift, collision, transform, and intracratonic. Basins could be further subdivided into three main depositional settings: deep basin-shallow water, deep basin-deep water, and shallow basin-shallow water. Thick basinal salts were remobilized into salt structures in all tectonic settings except intracratonic. Salt flow was due to inherent instability and differential loading in tectonically active settings. Hydrocarbon accumulations associated with these various platforms and basins followed a predictable, but not mutually exclusive, pattern related to the classification of evaporite settings presented in this paper. Reservoirs in platform and ramp settings tended to be of two types--depositional and diagenetic--with most of the diagenesis following patterns predicted by the porosity and plumbing established at or soon after evaporite emplacement. Ramp reservoirs were almost always found in Zone Y, while shelf reservoirs were most common in the grainstone shoals associated with rim or island-crest facies, or their dolomitized equivalents. Reservoirs associated with basinal evaporites were also depositional or diagenetic. Depositional reservoirs were almost all related to topography present during deposition of the carbonates in the basin, often immediately preceding or just beginning evaporitic conditions in the basin.

  16. Potentials and limits to basin stability estimation

    NASA Astrophysics Data System (ADS)

    Schultz, Paul; Menck, Peter J.; Heitzig, Jobst; Kurths, Jürgen

    2017-02-01

    Stability assessment methods for dynamical systems have recently been complemented by basin stability and derived measures, i.e. probabilistic statements whether systems remain in a basin of attraction given a distribution of perturbations. Their application requires numerical estimation via Monte Carlo sampling and integration of differential equations. Here, we analyse the applicability of basin stability to systems with basin geometries that are challenging for this numerical method, having fractal basin boundaries and riddled or intermingled basins of attraction. We find that numerical basin stability estimation is still meaningful for fractal boundaries but reaches its limits for riddled basins with holes.

  17. Hydrocarbon associations in evaporite basins

    SciTech Connect

    Warren, J.

    1988-02-01

    Evaporite deposition today is not representative of the diversity or scale of evaporites of the past. Ancient evaporites were deposited in two main settings: platform wide or basin wide. Platform evaporites were composed of relatively thin stratiform units (usually <5-10 m thick) deposited on either ramps or behind rimmed shelves. Basinal evaporites were deposited as thick bedded units 10s to 100s of m thick, and laid down in 4 main tectonic settings - rift, collision, transform, and intracratonic. Basins could be further subdivided into three main depositional settings: deep basin-shallow water, deep basin-deep water, and shallow basin-shallow water. Thick basinal salts were remobilized into salt structures in all tectonic settings except intracratonic. Salt flow was due to inherent instability and differential loading in tectonically active settings. Hydrocarbon accumulations associated with these various platforms and basins followed a predictable, but not mutually exclusive, pattern related to the classification of evaporite settings presented in this paper. Reservoirs in platform and ramp settings tended to be of two types - depositional and diagenetic - with most of the diagenesis following patterns predicted by the porosity and plumbing established at or soon after evaporite emplacement.

  18. New Light on Old Basins

    NASA Astrophysics Data System (ADS)

    Wood, C. A.; Collins, M. J. S.

    2011-03-01

    Great resolution and homogeneity of LRO WAC mosaics and LOLA altimetry suggest that Moscoviense sits in an older basin, explaining its thin crust and mare lavas, Orientale and SPA overlap older basins, and Wilhelms and McCauley were right about Imbrium.

  19. Atlantic marginal basins of Africa

    SciTech Connect

    Moore, G.T.

    1988-02-01

    The over 10,000-km long Atlantic margin of Africa is divisible into thirty basins or segments of the margin that collectively contain over 18.6 x 10/sup 6/ km/sup 3/ of syn-breakup and post-breakup sediments. Twenty of these basins contain a sufficiently thick volume of sediments to be considered prospects. These basins lie, at least partially, within the 200 m isobath. The distribution of source rocks is broad enough to give potential to each of these basins. The sedimentation patterns, tectonics, and timing of events differ from basin to basin and are related directly to the margin's complex history. Two spreading modes exist: rift and transform. Rifting dates from Late Triassic-Early Jurassic in the northwest to Early Cretaceous south of the Niger Delta. A complex transform fault system separated these two margins. Deep-water communication between the two basins became established in the middle Cretaceous. This Mesozoic-Cenozoic cycle of rifting and seafloor spreading has segmented the margin and where observable, basins tend to be bounded by these segments.

  20. Carbonylation and disassembly of the F-actin cytoskeleton in oxidant induced barrier dysfunction and its prevention by epidermal growth factor and transforming growth factor α in a human colonic cell line

    PubMed Central

    Banan, A; Zhang, Y; Losurdo, J; Keshavarzian, A

    2000-01-01

    BACKGROUND—Intestinal barrier dysfunction concomitant with high levels of reactive oxygen metabolites (ROM) in the inflamed mucosa have been observed in inflammatory bowel disease (IBD). The cytoskeletal network has been suggested to be involved in the regulation of barrier function. Growth factors (epidermal growth factor (EGF) and transforming growth factor α (TGF-α)) protect gastrointestinal barrier integrity against a variety of noxious agents. However, the underlying mechanisms of oxidant induced disruption and growth factor mediated protection remain elusive.
AIMS—To determine: (1) if oxidation and disassembly of actin (a key cytoskeletal component) plays a major role in ROM induced epithelial monolayer barrier dysfunction; and (2) if growth factor mediated protection involves prevention of theses alterations.
METHODS—Caco-2 monolayers were preincubated with EGF, TGF-α, or vehicle before incubation with ROM (H2O2 or HOCl). Effects on cell integrity, barrier function, and G- and F-actin (oxidation, disassembly, and assembly) were determined.
RESULTS—ROM dose dependently and significantly increased F- and G-actin oxidation (carbonylation), decreased the stable F-actin fraction (index of stability), and increased the monomeric G-actin fraction (index of disassembly). Concomitant with these changes were disruption of the actin cytoskeleton and loss of the monolayer barrier function. In contrast, growth factor pretreatment decreased actin oxidation and enhanced the stable F-actin, while in concert prevented actin disruption and restored normal barrier function of monolayers exposed to ROM. Cytochalasin-D, an inhibitor of actin assembly, not only caused actin disassembly and barrier dysfunction but also abolished the protective action of growth factors. Moreover, an actin stabilising agent, phalloidin, mimicked the protective actions of the growth factors.
CONCLUSIONS—Oxidation, disassembly, and instability of the actin cytoskeleton appears to

  1. FROM CONCEPT TO REALITY, IN-SITU DECOMMISSIONING OF THE P AND R REACTORS AT THE SAVANNAH RIVER SITE

    SciTech Connect

    Musall, J.; Blankenship, J.; Griffin, W.

    2012-01-09

    SRS recently completed an approximately three year effort to decommission two SRS reactors: P-Reactor (Building 105-P) and R-Reactor (Building 105-R). Completed in December 2011, the concurrent decommissionings marked the completion of two relatively complex and difficult facility disposition projects at the SRS. Buildings 105-P and 105-R began operating as production reactors in the early 1950s with the mission of producing weapons material (e.g., tritium and plutonium-239). The 'P' Reactor and was shutdown in 1991 while the 'R' Reactor and was shutdown in 1964. In the intervening period between shutdown and deactivation & decommissioning (D&D), Buildings 105-P and 105-R saw limited use (e.g., storage of excess heavy water and depleted uranium oxide). For Building 105-P, deactivation was initiated in April 2007 and was essentially complete by June 2010. For Building 105-R, deactivation was initiated in August 2008 and was essentially complete by September 2010. For both buildings, the primary objective of deactivation was to remove/mitigate hazards associated with the remaining hazardous materials, and thus prepare the buildings for in-situ decommissioning. Deactivation removed the following hazardous materials to the extent practical: combustibles/flammables, residual heavy water, acids, friable asbestos (as needed to protect workers performing deactivation and decommissioning), miscellaneous chemicals, lead/brass components, Freon(reg sign), oils, mercury/PCB containing components, mold and some radiologically-contaminated equipment. In addition to the removal of hazardous materials, deactivation included the removal of hazardous energy, exterior metallic components (representing an immediate fall hazard), and historical artifacts along with the evaporation of water from the two Disassembly Basins. Finally, so as to facilitate occupancy during the subsequent in-situ decommissioning, deactivation implemented repairs to the buildings and provided temporary power.

  2. Estancia Basin dynamic water budget.

    SciTech Connect

    Thomas, Richard P.

    2004-09-01

    The Estancia Basin lies about 30 miles to the east of Albuquerque, NM. It is a closed basin in terms of surface water and is somewhat isolated in terms of groundwater. Historically, the primary natural outlet for both surface water and groundwater has been evaporation from the salt lakes in the southeastern portion of the basin. There are no significant watercourses that flow into this basin and groundwater recharge is minimal. During the 20th Century, agriculture grew to become the major user of groundwater in the basin. Significant declines in groundwater levels have accompanied this agricultural use. Domestic and municipal use of the basin groundwater is increasing as Albuquerque population continues to spill eastward into the basin, but this use is projected to be less than 1% of agricultural use well into the 21st Century. This Water Budget model keeps track of the water balance within the basin. The model considers the amount of water entering the basin and leaving the basin. Since there is no significant surface water component within this basin, the balance of water in the groundwater aquifer constitutes the primary component of this balance. Inflow is based on assumptions for recharge made by earlier researchers. Outflow from the basin is the summation of the depletion from all basin water uses. The model user can control future water use within the basin via slider bars that set values for population growth, water system per-capita use, agricultural acreage, and the types of agricultural diversion. The user can also adjust recharge and natural discharge within the limits of uncertainty for those parameters. The model runs for 100 years beginning in 1940 and ending in 2040. During the first 55 years model results can be compared to historical data and estimates of groundwater use. The last 45 years are predictive. The model was calibrated to match to New Mexico Office of State Engineer (NMOSE) estimates of aquifer storage during the historical period by

  3. The deep Ionian Basin revisited

    NASA Astrophysics Data System (ADS)

    Tugend, Julie; Chamot-Rooke, Nicolas; Arsenikos, Stavros; Frizon de Lamotte, Dominique; Blanpied, Christian

    2016-04-01

    The deep Eastern Mediterranean Basins (Ionian and Herodotus) are characterized by thick sedimentary sequences overlying an extremely thinned basement evidenced from different geophysical methods. Yet, the nature of the crust (continental or oceanic) and the timing of the extreme crustal and lithosphere thinning in the different sub-basins remain highly controversial, casting doubts on the tectonic setting related to the formation of this segment of the North Gondwana paleo-margin. We focus on the Ionian Basin located at the western termination of the Eastern Mediterranean with the aim of identifying, characterizing and mapping the deepest sedimentary sequences. We present tentative age correlations relying on calibrations and observations from the surrounding margins and basins (Malta shelf and Escarpment, Cyrenaica margin, Sirte Basin, Apulian Platform). Two-ship deep refraction seismic data (Expanding Spread Profiles from the PASIPHAE cruise) combined with reprocessed reflection data (from the ARCHIMEDE survey) enabled us to present a homogeneous seismic stratigraphy across the basin and to investigate the velocity structure of its basement. Based on our results, and on a review of geological and geophysical observations, we suggest an Upper Triassic-Early Dogger age for the formation of the deep Ionian Basin. The nature of the underlying basement remains uncertain, both highly-thinned continental and slow-spreading type oceanic crust being compatible with the available constraints. The narrow size and relatively short-lived evolution of the Ionian Basin lead us to suggest that it is more likely the remnant of an immature oceanic basin than of a stable oceanic domain. Eventually, upscaling these results at the scale of the Eastern Mediterranean Basins highlights the complex interaction observed between two propagating oceans: The Central Atlantic and Neo-Tethys.

  4. RESERVES IN WESTERN BASINS PART IV: WIND RIVER BASIN

    SciTech Connect

    Robert Caldwell

    1998-04-01

    Vast quantities of natural gas are entrapped within various tight formations in the Rocky Mountain area. This report seeks to quantify what proportion of that resource can be considered recoverable under today's technological and economic conditions and discusses factors controlling recovery. The ultimate goal of this project is to encourage development of tight gas reserves by industry through reducing the technical and economic risks of locating, drilling and completing commercial tight gas wells. This report is the fourth in a series and focuses on the Wind River Basin located in west central Wyoming. The first three reports presented analyses of the tight gas reserves and resources in the Greater Green River Basin (Scotia, 1993), Piceance Basin (Scotia, 1995) and the Uinta Basin (Scotia, 1995). Since each report is a stand-alone document, duplication of language will exist where common aspects are discussed. This study, and the previous three, describe basin-centered gas deposits (Masters, 1979) which contain vast quantities of natural gas entrapped in low permeability (tight), overpressured sandstones occupying a central basin location. Such deposits are generally continuous and are not conventionally trapped by a structural or stratigraphic seal. Rather, the tight character of the reservoirs prevents rapid migration of the gas, and where rates of gas generation exceed rates of escape, an overpressured basin-centered gas deposit results (Spencer, 1987). Since the temperature is a primary controlling factor for the onset and rate of gas generation, these deposits exist in the deeper, central parts of a basin where temperatures generally exceed 200 F and drill depths exceed 8,000 feet. The abbreviation OPT (overpressured tight) is used when referring to sandstone reservoirs that comprise the basin-centered gas deposit. Because the gas resources trapped in this setting are so large, they represent an important source of future gas supply, prompting studies to

  5. Anticancer peptide CIGB-300 binds to nucleophosmin/B23, impairs its CK2-mediated phosphorylation, and leads to apoptosis through its nucleolar disassembly activity.

    PubMed

    Perera, Yasser; Farina, Hernán G; Gil, Jeovanis; Rodriguez, Arielis; Benavent, Fernando; Castellanos, Lila; Gómez, Roberto E; Acevedo, Boris E; Alonso, Daniel F; Perea, Silvio E

    2009-05-01

    CIGB-300, formerly known as P15-tat, is a proapoptotic peptide with established antiproliferative activity in vitro and antitumoral activity in vivo. This hypothesis-driven peptide was initially selected for its ability to impair the in vitro CK2-mediated phosphorylation in one of its substrates through direct binding to the conserved acidic phosphoaceptor domain. However, the actual in vivo target(s) on human cancer cells among the hundreds of CK2 substrates as well as the subsequent events that lead to apoptosis on tumor cells remains to be determined. In this work, we identified the multifunctional oncoprotein nucleophosmin/B23 as a major target for CIGB-300. In vivo, the CIGB-300-B23 interaction was shown by pull-down experiments and confirmed by the early in situ colocalization of both molecules in the cell nucleolus. Moreover, CIGB-300 inhibits the CK2-mediated phosphorylation of B23 in a dose-dependent fashion both in vitro and in vivo as shown using the recombinant GST fusion protein and the metabolic labeling approach, respectively. Such phosphorylation impairment was correlated with the ability of CIGB-300 to induce nucleolar disassembly as documented by the use of established markers for nucleolar structure. Finally, we showed that such a sequence of events leads to the rapid and massive onset of apoptosis both at the molecular and cellular levels. Collectively, these findings provide important clues by which the CIGB-300 peptide exerts its proapoptotic effect on tumor cells and highlights the suitability of the B23/CK2 pathway for cancer-targeted therapy.

  6. In situ AFM Study of Amelogenin Assembly and Disassembly Dynamics on Charged Surfaces Provides Insights on Matrix Protein Self-Assembly

    PubMed Central

    Chen, Chun-Long; Bromley, Keith M.

    2012-01-01

    Because self-assembly of matrix proteins is a key step in hard tissue mineralization, developing an understanding of the assembly pathways and underlying mechanisms is likely to be important for successful hard tissue engineering. While many studies of matrix protein assembly have been performed on bulk solutions, in vivo these proteins are likely to be in contact with charged biological surfaces composed of lipids, proteins, or minerals. Here we report the results of an in situ AFM study of self-assembly by amelogenin - the principal protein of the extracellular matrix in developing enamel - in contact with two different charged substrates: hydrophilic negatively charged bare mica and positively charged 3-aminopropyl triethoxysilane (APS) silanized mica. First we demonstrate an AFM-based protocol for determining the size of both amelogenin monomers and oligomers. Using this protocol, we find that, although amelogenin exists primarily as ∼26 nm in diameter nanospheres in bulk solution at pH8.0 studied by DLS, it behaves dramatically differently upon interacting with charged substrates at the same pH, and exhibits complex substrate-dependent assembly pathways and dynamics. On positively charged APS-treated mica surfaces, amelogenin forms a relatively uniform population of decameric oligomers which then transforms into two main populations: higher-order assemblies of oligomers and amelogenin monomers, while on negatively charged bare mica surfaces, it forms a film of monomers that exhibits tip-induced desorption and patterning. The present study represents a successful attempt to identify the size of amelogenin oligomers and to directly monitor assembly and disassembly dynamics on surfaces. The findings have implications for amelogenin-controlled calcium phosphate mineralization in vitro and may offer new insights into in vivo self-assembly of matrix proteins, as well as their control over hard tissue formation. PMID:21916473

  7. Ultraviolet microbeam irradiations of epithelial and spermatocyte spindles suggest that forces act on the kinetochore fibre and are not generated by its disassembly.

    PubMed

    Spurck, T; Forer, A; Pickett-Heaps, J

    1997-01-01

    Ultraviolet (UV) microbeam irradiations of crane-fly spermatocyte and newt epithelial spindles severed kinetochore fibres (KT-fibres), creating areas of reduced birefringence (ARBs): the remnant KT-fibre consists of two "stubs," a pole-stub attached to the pole and a KT-stub attached to the kinetochore. KT-stubs remained visible but pole-stubs soon became undetectable [Forer et al., 1996]. At metaphase, in both cell types the KT-stub often changed orientation immediately after irradiation and its tip steadily moved poleward. In spermatocytes, the chromosome attached to the KT-stub remained at the equator as the KT-stub elongated. In epithelial cells, the KT-stub sometimes elongated as the associated chromosome remained at the equator; other times the associated chromosome moved poleward together with the KT-stub, albeit only a short distance toward the pole. When an ARB was generated at anaphase, chromosome(s) with a KT-stub often continued to move poleward. In spermatocytes, this movement was accompanied by steady elongation of the KT-stub. In epithelial cells, chromosomes accelerated polewards after irradiation until the KT-stubs reached the pole, after which chromosome movement returned to normal speeds. In some epithelial cells fine birefringent fibres by chance were present along one edge of ARBs; these remnant fibres buckled and broke as the KT-stub and chromosome moved polewards. Similarly, KT-stubs that moved into pole stubs (or astral fibres) caused the pole stubs (or astral fibres) to bend sharply from the point of impact. Our results contradict models of chromosome movement that postulate that force is generated by the kinetochore disassembling the KT-fibre. Instead, these results suggest that poleward directed forces act on the KT-fibre and the KT-stub and suggest that continuity of microtubules between kinetochore and pole is not obligatory for achieving anaphase motion to the pole.

  8. Caspase-activated DNase is necessary and sufficient for oligonucleosomal DNA breakdown, but not for chromatin disassembly during caspase-dependent apoptosis of LN-18 glioblastoma cells.

    PubMed

    Sánchez-Osuna, María; Garcia-Belinchón, Mercè; Iglesias-Guimarais, Victoria; Gil-Guiñón, Estel; Casanelles, Elisenda; Yuste, Victor J

    2014-07-04

    Caspase-dependent apoptosis is a controlled type of cell death characterized by oligonucleosomal DNA breakdown and major nuclear morphological alterations. Other kinds of cell death do not share these highly distinctive traits because caspase-activated DNase (DFF40/CAD) remains inactive. Here, we report that human glioblastoma multiforme-derived LN-18 cells do not hydrolyze DNA into oligonucleosomal fragments after apoptotic insult. Furthermore, their chromatin remains packaged into a single mass, with no signs of nuclear fragmentation. However, ultrastructural analysis reveals that nuclear disassembly occurs, although compacted chromatin does not localize into apoptotic nuclear bodies. Caspases become properly activated, and ICAD, the inhibitor of DFF40/CAD, is correctly processed. Using cell-free in vitro assays, we show that chromatin from isolated nuclei of LN-18 cells is suitable for hydrolysis into oligonuclesomal fragments by staurosporine-pretreated SH-SY5Y cytoplasms. However, staurosporine-pretreated LN-18 cytoplasms do not induce DNA laddering in isolated nuclei from either LN-18 or SH-SY5Y cells because LN-18 cells express lower amounts of DFF40/CAD. DFF40/CAD overexpression makes LN-18 cells fully competent to degrade their DNA into oligonucleosome-sized fragments, and yet they remain unable to arrange their chromatin into nuclear clumps after apoptotic insult. Indeed, isolated nuclei from LN-18 cells were resistant to undergoing apoptotic nuclear morphology in vitro. The use of LN-18 cells has uncovered a previously unsuspected cellular model, whereby a caspase-dependent chromatin package is DFF40/CAD-independent, and DFF40/CAD-mediated double-strand DNA fragmentation does not warrant the distribution of the chromatin into apoptotic nuclear bodies. The studies highlight a not-yet reported DFF40/CAD-independent mechanism driving conformational nuclear changes during caspase-dependent cell death.

  9. Streamlined Approach for Environmental Restoration (SAFER) Plan for Corrective Action Unit 117: Area 26 Pluto Disassembly Facility, Nevada Test Site, Nevada With Errata Sheets, Revision 0

    SciTech Connect

    Pat Matthews

    2007-09-01

    This Streamlined Approach for Environmental Restoration (SAFER) Plan addresses the actions needed to achieve closure for Corrective Action Unit (CAU) 117, Pluto Disassembly Facility, identified in the Federal Facility Agreement and Consent Order. Corrective Action Unit 117 consists of one Corrective Action Site (CAS), CAS 26-41-01, located in Area 26 of the Nevada Test Site. This plan provides the methodology for field activities needed to gather the necessary information for closing CAS 26-41-01. There is sufficient information and process knowledge from historical documentation and investigations of similar sites regarding the expected nature and extent of potential contaminants to recommend closure of CAU 117 using the SAFER process. Additional information will be obtained by conducting a field investigation before finalizing the appropriate corrective action for this CAS. The results of the field investigation will support a defensible recommendation that no further corrective action is necessary following SAFER activities. This will be presented in a Closure Report that will be prepared and submitted to the Nevada Division of Environmental Protection (NDEP) for review and approval. The site will be investigated to meet the data quality objectives (DQOs) developed on June 27, 2007, by representatives of NDEP; U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Site Office; Stoller-Navarro Joint Venture; and National Security Technologies, LLC. The DQO process was used to identify and define the type, amount, and quality of data needed to determine and implement appropriate corrective actions for CAS 26-41-01 in CAU 117.

  10. A two-pronged structural analysis of retroviral maturation indicates that core formation proceeds by a disassembly-reassembly pathway rather than a displacive transition.

    PubMed

    Keller, Paul W; Huang, Rick K; England, Matthew R; Waki, Kayoko; Cheng, Naiqian; Heymann, J Bernard; Craven, Rebecca C; Freed, Eric O; Steven, Alasdair C

    2013-12-01

    Retrovirus maturation involves sequential cleavages of the Gag polyprotein, initially arrayed in a spherical shell, leading to formation of capsids with polyhedral or conical morphology. Evidence suggests that capsids assemble de novo inside maturing virions from dissociated capsid (CA) protein, but the possibility persists of a displacive pathway in which the CA shell remains assembled but is remodeled. Inhibition of the final cleavage between CA and spacer peptide SP1/SP blocks the production of mature capsids. We investigated whether retention of SP might render CA assembly incompetent by testing the ability of Rous sarcoma virus (RSV) CA-SP to assemble in vitro into icosahedral capsids. Capsids were indeed assembled and were indistinguishable from those formed by CA alone, indicating that SP was disordered. We also used cryo-electron tomography to characterize HIV-1 particles produced in the presence of maturation inhibitor PF-46396 or with the cleavage-blocking CA5 mutation. Inhibitor-treated virions have a shell that resembles the CA layer of the immature Gag shell but is less complete. Some CA protein is generated but usually not enough for a mature core to assemble. We propose that inhibitors like PF-46396 bind to the Gag lattice where they deny the protease access to the CA-SP1 cleavage site and prevent the release of CA. CA5 particles, which exhibit no cleavage at the CA-SP1 site, have spheroidal shells with relatively thin walls. It appears that this lattice progresses displacively toward a mature-like state but produces neither conical cores nor infectious virions. These observations support the disassembly-reassembly pathway for core formation.

  11. K-Basins design guidelines

    SciTech Connect

    Roe, N.R.; Mills, W.C.

    1995-06-01

    The purpose of the design guidelines is to enable SNF and K Basin personnel to complete fuel and sludge removal, and basin water mitigation by providing engineering guidance for equipment design for the fuel basin, facility modifications (upgrades), remote tools, and new processes. It is not intended to be a purchase order reference for vendors. The document identifies materials, methods, and components that work at K Basins; it also Provides design input and a technical review process to facilitate project interfaces with operations in K Basins. This document is intended to compliment other engineering documentation used at K Basins and throughout the Spent Nuclear Fuel Project. Significant provisions, which are incorporated, include portions of the following: General Design Criteria (DOE 1989), Standard Engineering Practices (WHC-CM-6-1), Engineering Practices Guidelines (WHC 1994b), Hanford Plant Standards (DOE-RL 1989), Safety Analysis Manual (WHC-CM-4-46), and Radiological Design Guide (WHC 1994f). Documents (requirements) essential to the engineering design projects at K Basins are referenced in the guidelines.

  12. Reconstructing vanished ocean basins

    NASA Astrophysics Data System (ADS)

    Müller, D.; Sdrolias, M.; Gaina, C.

    2006-05-01

    The large-scale patterns of mantle convection are mainly dependent on the history of subduction. Therefore some of the primary constraints for subduction models are given by of the location of subduction zones through time, and of the convergence vectors and age of subducted lithosphere. This requires the complete reconstruction of ocean floor through time, including the main ocean basins, back-arc basins, and now subducted ocean crust, and tying these kinematic models to geodynamic simulations. We reconstruct paleo- oceans by creating "synthetic plates", the locations and geometry of which is established on the basis of preserved ocean crust (magnetic lineations and fracture zones), geological data, paleogeography, and the rules of plate tectonics. We use a merged moving hotspot (Late Cretaceous-present) and palaeomagnetic/fixed hotspot (Early Cretaceous) reference frame, coupled with reconstructed spreading histories of the Pacific, Phoenix and Farallon plates and the plates involved in the Tethys oceanic domain. Based on this approach we have created a set of global oceanic paleo-isochrons and paleo-oceanic age grids. The grids also provide the first complete global set of paleo-basement depth maps, including now subducted ocean floor, for the last 130 million years based on a depth-age relationship. We show that the mid-Cretaceous sealevel highstand was primarily caused by two main factors: (1) the "supercontinent breakup effect", which resulted in the creation of the mid-Atlantic and Indian Ocean ridges at the expense of subducting old ocean floor in the Tethys and (2) by a changing age-area distribution of Pacific ocean floor through time, resulting from the subduction of the Pacific-Izanagi, Pacific-Phoenix and Pacific-Farallon ridges. These grids provide model constraints for subduction dynamics through time and represent a framework for backtracking biogeographic and sediment data from ocean drilling and for constraining the opening/closing of oceanic

  13. Aleutian basin oceanic crust

    USGS Publications Warehouse

    Christeson, Gail L.; Barth, Ginger A.

    2015-01-01

    We present two-dimensional P-wave velocity structure along two wide-angle ocean bottom seismometer profiles from the Aleutian basin in the Bering Sea. The basement here is commonly considered to be trapped oceanic crust, yet there is a change in orientation of magnetic lineations and gravity features within the basin that might reflect later processes. Line 1 extends ∼225 km from southwest to northeast, while Line 2 extends ∼225 km from northwest to southeast and crosses the observed change in magnetic lineation orientation. Velocities of the sediment layer increase from 2.0 km/s at the seafloor to 3.0–3.4 km/s just above basement, crustal velocities increase from 5.1–5.6 km/s at the top of basement to 7.0–7.1 km/s at the base of the crust, and upper mantle velocities are 8.1–8.2 km/s. Average sediment thickness is 3.8–3.9 km for both profiles. Crustal thickness varies from 6.2 to 9.6 km, with average thickness of 7.2 km on Line 1 and 8.8 km on Line 2. There is no clear change in crustal structure associated with a change in orientation of magnetic lineations and gravity features. The velocity structure is consistent with that of normal or thickened oceanic crust. The observed increase in crustal thickness from west to east is interpreted as reflecting an increase in melt supply during crustal formation.

  14. The Amazon basin in transition.

    PubMed

    Davidson, Eric A; de Araújo, Alessandro C; Artaxo, Paulo; Balch, Jennifer K; Brown, I Foster; C Bustamante, Mercedes M; Coe, Michael T; DeFries, Ruth S; Keller, Michael; Longo, Marcos; Munger, J William; Schroeder, Wilfrid; Soares-Filho, Britaldo S; Souza, Carlos M; Wofsy, Steven C

    2012-01-18

    Agricultural expansion and climate variability have become important agents of disturbance in the Amazon basin. Recent studies have demonstrated considerable resilience of Amazonian forests to moderate annual drought, but they also show that interactions between deforestation, fire and drought potentially lead to losses of carbon storage and changes in regional precipitation patterns and river discharge. Although the basin-wide impacts of land use and drought may not yet surpass the magnitude of natural variability of hydrologic and biogeochemical cycles, there are some signs of a transition to a disturbance-dominated regime. These signs include changing energy and water cycles in the southern and eastern portions of the Amazon basin.

  15. Basin development and petroleum potential of offshore Otway basin, Australia

    SciTech Connect

    Williamson, P.E.; O'Brien, G.W.; Swift, M.G.; Scherl, A.S.; Marlow, M.S.; Exon, N.F.; Falvey, D.A.; Lock, J.; Lockwood, K.

    1987-05-01

    The Bass Strait region in southeastern Australia contains three sedimentary basins, which are, from east to west, the Gippsland, Bass, and Otway basins. The offshore Gippsland basin is Australia's most prolific petroleum-producing province and supplies over 90% of the country's production. In contrast, exploration has been unsuccessful in the offshore portion of the Otway basin; 17 wells have been drilled, and although shows of oil and gas have been common, no commercial discoveries have been made. Many of these wells, drilled in the 1960s and 1970s, were sited using poor-quality seismic data and, as a consequence, were frequently off structure. Seismic data quality has, however, improved significantly in recent years. The present study by the Australian Bureau of Mineral Resources (BMR) involved the collection, in the offshore Otway basin, of 3700 km of high-quality, 48-channel seismic reflection data by the BMR research vessel R/V Rig Seismic. These data have been integrated with existing industry seismic data, well data, limited dredged material, and geohistory analyses in a framework study of basin development and hydrocarbon potential in this under-explored area. The offshore Otway basin extends 500 km along the southern coastline and is typically 50 km wide in water depths of less than 200 m. It contains up to 10 km of predominantly late Mesozoic to early Cenozoic sediments, which are overlain by a thin sequence of middle to late Tertiary shelf carbonates. It has been divided into three main structural elements: the Mussel Platform in the east, the central Voluta Trough, and the Crayfish Platform in the west. The basin was initiated at the end of the Jurassic as part of the Bassian rift. Up to 6 km of Lower Cretaceous sediments were deposited prior to breakup at the end of the Early Cretaceous and the onset of sea-floor spreading between Australia and Antarctica.

  16. Tectonic framework of Turkish sedimentary basins

    SciTech Connect

    Yilmaz, P.O. )

    1988-08-01

    Turkey's exploration potential primarily exists in seven onshore (Southeast Turkey platform, Tauride platform, Pontide platform, East Anatolian platform, Interior, Trace, and Adana) basins and four offshore (Black Sea, Marmara Sea, Aegean Sea, and Mediterranean Sea) regional basins formed during the Mesozoic and Tertiary. The Mesozoic basins are the onshore basins: Southeast Turkey, Tauride, Pontide, East Anatolian, and Interior basins. Due to their common tectonic heritage, the southeast Turkey and Tauride basins have similar source rocks, structural growth, trap size, and structural styles. In the north, another Mesozoic basin, the Pontide platform, has a much more complex history and very little in common with the southerly basins. The Pontide has two distinct parts; the west has Paleozoic continental basement and the east is underlain by island-arc basement of Jurassic age. The plays are in the upper Mesozoic rocks in the west Pontide. The remaining Mesozoic basins of the onshore Interior and East Anatolian basins are poorly known and very complex. Their source, reservoir, and seal are not clearly defined. The basins formed during several orogenic phases in mesozoic and Tertiary. The Cenozoic basins are the onshore Thrace and Adana basins, and all offshore regional basins formed during Miocene extension. Further complicating the onshore basins evolution is the superposition of Cenozoic basins and Mesozoic basins. The Thrace basin in the northwest and Adana basin in the south both originate from Tertiary extension over Tethyan basement and result in a similar source, reservoir, and seal. Local strike-slip movement along the North Anatolian fault modifies the Thrace basin structures, influencing its hydrocarbon potential.

  17. COMPUTATIONAL METHODS FOR ASYNCHRONOUS BASINS

    PubMed Central

    Dinwoodie, Ian H

    2016-01-01

    For a Boolean network we consider asynchronous updates and define the exclusive asynchronous basin of attraction for any steady state or cyclic attractor. An algorithm based on commutative algebra is presented to compute the exclusive basin. Finally its use for targeting desirable attractors by selective intervention on network nodes is illustrated with two examples, one cell signalling network and one sensor network measuring human mobility. PMID:28154501

  18. Provenance and basin evolution, Zhada basin, southwestern Tibet

    NASA Astrophysics Data System (ADS)

    Saylor, J.; Decelles, P.; Gehrels, G.; Kapp, P.

    2007-12-01

    The Zhada basin is a late Miocene - Pliocene intermontane basin situated at high elevations in the Himalayan hinterland. The fluvial and lacustrine sediments of the Zhada formation are undeformed and sit in angular unconformity above the deformed Tethyan Sedimentary Sequence (TSS). The basin sits just south of the Indus suture in a structural position occupied elsewhere in the Himalayan orogen by some of the highest mountains on earth, including Everest. The occurrence of a basin at this location demands explanation. Currently, the Sutlej River flows parallel to the structural grain of the Himalaya, westward through the basin, towards the Leo Pargil (Qusum) range. Near the range front it takes a sharp southward turn, cuts across the structural grain of the Himalaya and out into the Gangetic foreland. Palaeocurrent indicators in the lower part of the Zhada formation show that the basin originated as a northwest flowing axial river. Palaeocurrent indicators are consistently northwest oriented, even to within to within 10 km of the Leo Pargil range front in the north-western end of the basin. This implies that at the onset of sedimentation in Zhada basin the Leo Pargil range was not a barrier as it is today. In the upper part of the Zhada formation, palaeocurrent indicators are generally directed towards the centre of the basin. In the central and southern portions of the basin this indicates a transition from an axial, northwest flowing river to prograding fluvial and alluvial fans. However, in the north-western part of the basin the change between lower and upper Zhada formation involves a complete drainage reversal. This change in palaeocurrent orientation is also reflected in the detrital zircon signal from basin sediments. Low in the Zhada formation the detrital zircon signal is dominated by zircons from the Kailash (Gangdese) batholith (or associated extrusives, see below). However, higher in the sections, a local source, either from the TSS or the core of the

  19. Bafilomycin A1 inhibits proteolytic cleavage and hydration but not yolk crystal disassembly or meiosis during maturation of sea bass oocytes.

    PubMed

    Selman, K; Wallace, R A; Cerdà, J

    2001-08-01

    Oocytes of the black sea bass, Centropristes striata, were enlarged in volume more than three-fold over a 24-hr period during oocyte maturation, both in vivo and in vitro. At the same time, the opaque oocytes clarified while the crystalline yolk inclusions lost their ordered structure, fused with one another, and formed a continuous electron-lucent mass. The oocyte size increase was due almost entirely to water uptake, which was accompanied by the accumulation of Na+, K+, and free amino acids (FAAs). The absolute amounts of each of these small molecular weight osmotic effectors increased 2x, 4x, and over 10x, respectively, indicating that the generation of FAAs is the major cause of water uptake during maturation. Amino acid analyses indicated that the amounts of all amino acids except taurine increased, so that selective amino acids were not produced during maturation. The increase in FAAs was accompanied by the loss of certain high-molecular-weight yolk proteins and the generation of many smaller peptides. Oocytes stimulated to undergo maturation in the presence of bafilomycin A1, a specific inhibitor of the vacuolar ATPase-dependent proton pump, clarified and underwent maturation but did not increase significantly in size. Cytological examination revealed that yolk crystals fused and became homogeneous but maintained their electron density. No evidence of proteolysis was found in bafilomycin A1-treated oocytes and the generation of FAAs together with hydration was inhibited in a dose-dependent manner (I50 = 3 nM bafilomycin A1). Taken together, we postulate that the pronounced oocyte hydration in marine teleosts that spawn pelagic (floating) eggs is accomplished by a two-step process whereby (i) K+ influx promotes yolk crystal disassembly and yolk sphere fusion and (ii) acidification of the yolk spheres activates yolk proteolysis and concomitant hydration. Bafilomycin A1 inhibits only the second step so that many of the events of oocyte maturation, including

  20. Flexural analysis of two broken foreland basins; Late Cenozoic Bermejo basin and Early Cenozoic Green River basin

    SciTech Connect

    Flemings, P.B.; Jordan, T.E.; Reynolds, S.

    1986-05-01

    Lithospheric flexure that generates basin in a broke foreland setting (e.g., the Laramide foreland of Wyoming) is a three-dimensional system related to shortening along basin-bounding faults. The authors modeled the elastic flexure in three dimensions for two broken foreland basins: the early Cenozoic Green River basin and the analogous late Cenozoic Bermejo basin of Argentina. Each basin is located between a thrust belt and a reverse-fault-bounded basement uplift. Both basins are asymmetric toward the basement uplifts and have a central basement high: the Rock Springs uplift and the Pie de Palo uplift, respectively. The model applies loads generated by crustal thickening to an elastic lithosphere overlying a fluid mantle. Using the loading conditions of the Bermejo basin based on topography, limited drilling, and reflection and earthquake seismology, the model predicts the current Bermejo basin geometry. Similarly, flexure under the loading conditions in the Green River basin, which are constrained by stratigraphy, well logs, and seismic profiling and summed for Late Cretaceous (Lance Formation) through Eocene (Wasatch Formation), successfully models the observed geometry of the pre-Lance surface. Basin depocenters (> 4 km for the Green River basin; > 7 km for the Bermejo basin) and central uplifts are predicted to result from constructive interference of the nonparallel applied loads. Their Bermejo model implies that instantaneous basin geometry is successfully modeled by crustal loading, whereas the Green River basin analysis suggests that basin evolution can be modeled over large time steps (e.g., 20 Ma). This result links instantaneous basin geometry to overall basin evolution and is a first step in predicting stratigraphic development.

  1. CALUTRON ASSEMBLING AND DISASSEMBLING APPARATUS

    DOEpatents

    Andrews, R.E.

    1959-01-27

    The construction of a calutron tank is described, whcre the face plate of the tank carrying the ion separating mechanism may be inserted or withdrawn with a minimum of difficulty, even though the plate has considerable mass and the center of gravity of the plate assembly lies within the tank. In general, the plate is pivoted at its lower end by a specially designed hinge, whereby the weight of ths plate rests on the hinge when the plato is inserted in the tank opening. A pistoncylinder arrangement is mounted on the tank and attached at the top of the plate to produce sufficient force to pivot the plate out to a point where it withdraws by its own weight and to retard the natural tendency of the plate to close with heavy impact due to the unbalanced center of gravity of the plate assembly.

  2. Detecting Cavitation Pitting Without Disassembly

    NASA Technical Reports Server (NTRS)

    Barkhoudarian, S.

    1986-01-01

    Technique for detecting cavitation pitting in pumps, turbines, and other machinery uses low-level nuclear irradiation. Isotopes concentrated below surface emit gamma radiation, a portion of which is attenuated by overlying material. Where there are cavitation pits, output of gamma-ray detector fluctuates as detector is scanned near pits. Important to detect cavitation pits because nozzle, turbine blade, or other pump component weakened by cavitation could fail catastrophically and cause machine to explode.

  3. CALUTRON ASSEMBLING AND DISASSEMBLING APPARATUS

    DOEpatents

    Andrews, R.E.

    1959-01-27

    A closure plate assembly is presented for a calutron tank. Due to the size and weight of the calutron tank a special face plate, hinges and latch construction are required. The salient feature of the invention is the provision of a face plate carrying the ion separating niechanism and adapted to close an open side of a calutron tank. A spring-type hinge secured to the face plate at one end prevents injury to the sealing gasket as the face plate is inserted and withdrawn. In additions a hinged support for the face plate comprises readily separable hinge elements, so that the face plate may first be swung outwardly from its operative position far enough to clear the ion separating meehanism carried thereby, and may thereafter be elevated and transported by a convcntional overhead crane.

  4. Paleothermometry of the Sydney Basin

    SciTech Connect

    Middleton, M.F.; Schmidt, P.W.

    1982-07-10

    Evidence from overprinting of magnetizations of Late Permian and Mesozoic rocks and from the rank of Permian coals and Mesozoic phytoclasts (coal particles) suggests that surface rocks in the Sydney Basin, eastern Australia, have been raised to temperatures of the order of 200 /sup 0/C or higher. As vitrinite reflectance, an index of coal rank or coalification, is postulated to vary predictably with temperature and time, estimates of the paleotemperatures in the Sydney Basin based on observed vitrinite reflectance measurements can be made in conjunction with reasonable assumptions about the tectonic and thermal histories of the basin. These estimates give maximum paleotemperatures of present day surface rocks in the range 60--249 /sup 0/C, depending on factors such as location in the basin, the thickness of the sediment eroded, and the maximum paleogeothermal gradient. Higher coal rank and, consequently, larger eroded thicknesses and paleogeothermal gradients occur along the eastern edge of the basin and may be related to seafloor spreading in the Tasman Sea on the basin's eastern margin. A theory of thermal activation of magnetization entailing the dependence of magnetic viscosity on the size distribution of the magnetic grains is used to obtain an independent estimate of the maximum paleotemperatures in the Sydney Basin. This estimate places the maximum paleotemperature in the range 250--300 /sup 0/C along the coastal region. Both coalification and thermal activation of magnetization models provide strong evidence of elevated paleotemperatures, which in places exceed 200 /sup 0/C, and the loss of sediment thicknesses in excess of 1 km due to erosion.

  5. Floor of Hellas Basin

    NASA Technical Reports Server (NTRS)

    2002-01-01

    [figure removed for brevity, see original site]

    With a diameter of roughly 2000 km and a depth of over 7 km, the Hellas Basin is the largest impact feature on Mars. Because of its great depth, there is significantly more atmosphere to peer through in order to see its floor, reducing the quality of the images taken from orbit. This THEMIS image straddles a scarp between the Hellas floor and an accumulation of material at least a half kilometer thick that covers much of the floor. The southern half of the image contains some of this material. Strange ovoid landforms are present here that give the appearance of flow. It is possible that water ice or even liquid water was present in the deposits and somehow responsible for the observed landscape. The floor of Hellas remains a poorly understood portion of the planet that should benefit from the analysis of new THEMIS data.

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

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

  6. Hydrogeologic framework of sedimentary deposits in six structural basins, Yakima River basin, Washington

    USGS Publications Warehouse

    Jones, M.A.; Vaccaro, J.J.; Watkins, A.M.

    2006-01-01

    The hydrogeologic framework was delineated for the ground-water flow system of the sedimentary deposits in six structural basins in the Yakima River Basin, Washington. The six basins delineated, from north to south are: Roslyn, Kittitas, Selah, Yakima, Toppenish, and Benton. Extent and thicknesses of the hydrogeologic units and total basin sediment thickness were mapped for each basin. Interpretations were based on information from about 4,700 well records using geochemical, geophysical, geologist's or driller's logs, and from the surficial geology and previously constructed maps and well interpretations. The sedimentary deposits were thickest in the Kittitas Basin reaching a depth of greater than 2,000 ft, followed by successively thinner sedimentary deposits in the Selah basin with about 1,900 ft, Yakima Basin with about 1,800 ft, Toppenish Basin with about 1,200 ft, Benton basin with about 870 ft and Roslyn Basin with about 700 ft.

  7. Inversion of Extensional Sedimentary Basins

    NASA Astrophysics Data System (ADS)

    Buiter, Susanne J. H.; Pfiffner, O. Adrian

    The evolution of extensional sedimentary basins is governed by the surrounding stress field and can, therefore, be expected to be highly sensitive to variations in these stresses. Important changes in basin geometry are to be expected in the case of an even short-lived reversal from extension to compression. We investigate the evolu- tion of fold and thrust structures which form in compression after extension, when basin forming processes have come to a complete stop. To this purpose, we use a two- dimensional, viscoplastic model and start our experiments from a pre-existing exten- sional geometry. We illustrate the sensitivity of the evolving structures to inherited extensional geometry, sedimentary and erosional processes, and material properties. One series of our model experiments involves the upper- to middle crust only in order to achieve a high detail in the basin area. We find that our results agree with examples from nature and analogue studies in, among others, the uplift and rotation of syn-rift sediments, the propagation of shear zones into the post-rift sediments and, in specific cases, the development of back-thrusts or basement short-cut faults. We test the out- come of these models by performing a second series of model simulations in which basins on a continental margin are inverted through their progressive approach of a subduction zone. These latter models are on the scale of the whole upper mantle.

  8. Water Accounting from Ungauged Basins

    NASA Astrophysics Data System (ADS)

    Bastiaanssen, W. G.; Savenije, H.

    2014-12-01

    Water scarcity is increasing globally. This requires a more accurate management of the water resources at river basin scale and understanding of withdrawals and return flows; both naturally and man-induced. Many basins and their tributaries are, however, ungauged or poorly gauged. This hampers sound planning and monitoring processes. While certain countries have developed clear guidelines and policies on data observatories and data sharing, other countries and their basin organization still have to start on developing data democracies. Water accounting quantifies flows, fluxes, stocks and consumptive use pertaining to every land use class in a river basin. The objective is to derive a knowledge base with certain minimum information that facilitates decision making. Water Accounting Plus (WA+) is a new method for water resources assessment reporting (www.wateraccounting.org). While the PUB framework has yielded several deterministic models for flow prediction, WA+ utilizes remote sensing data of rainfall, evaporation (including soil, water, vegetation and interception evaporation), soil moisture, water levels, land use and biomass production. Examples will be demonstrated that show how remote sensing and hydrological models can be smartly integrated for generating all the required input data into WA+. A standard water accounting system for all basins in the world - with a special emphasis on data scarce regions - is under development. First results of using remote sensing measurements and hydrological modeling as an alternative to expensive field data sets, will be presented and discussed.

  9. Testing for Basins of Wada

    PubMed Central

    Daza, Alvar; Wagemakers, Alexandre; Sanjuán, Miguel A. F.; Yorke, James A.

    2015-01-01

    Nonlinear systems often give rise to fractal boundaries in phase space, hindering predictability. When a single boundary separates three or more different basins of attraction, we say that the set of basins has theWada property and initial conditions near that boundary are even more unpredictable. Many physical systems of interest with this topological property appear in the literature. However, so far the only approach to study Wada basins has been restricted to two-dimensional phase spaces. Here we report a simple algorithm whose purpose is to look for the Wada property in a given dynamical system. Another benefit of this procedure is the possibility to classify and study intermediate situations known as partially Wada boundaries. PMID:26553444

  10. Testing for Basins of Wada.

    PubMed

    Daza, Alvar; Wagemakers, Alexandre; Sanjuán, Miguel A F; Yorke, James A

    2015-11-10

    Nonlinear systems often give rise to fractal boundaries in phase space, hindering predictability. When a single boundary separates three or more different basins of attraction, we say that the set of basins has the Wada property and initial conditions near that boundary are even more unpredictable. Many physical systems of interest with this topological property appear in the literature. However, so far the only approach to study Wada basins has been restricted to two-dimensional phase spaces. Here we report a simple algorithm whose purpose is to look for the Wada property in a given dynamical system. Another benefit of this procedure is the possibility to classify and study intermediate situations known as partially Wada boundaries.

  11. Dynamic reorganization of river basins.

    PubMed

    Willett, Sean D; McCoy, Scott W; Perron, J Taylor; Goren, Liran; Chen, Chia-Yu

    2014-03-07

    River networks evolve as migrating drainage divides reshape river basins and change network topology by capture of river channels. We demonstrate that a characteristic metric of river network geometry gauges the horizontal motion of drainage divides. Assessing this metric throughout a landscape maps the dynamic states of entire river networks, revealing diverse conditions: Drainage divides in the Loess Plateau of China appear stationary; the young topography of Taiwan has migrating divides driving adjustment of major basins; and rivers draining the ancient landscape of the southeastern United States are reorganizing in response to escarpment retreat and coastal advance. The ability to measure the dynamic reorganization of river basins presents opportunities to examine landscape-scale interactions among tectonics, erosion, and ecology.

  12. Origin of the earth's ocean basins

    NASA Technical Reports Server (NTRS)

    Frey, H.

    1977-01-01

    The earth's original ocean basins are proposed to be mare-type basins produced 4 billion y.a. by the flux of asteroid-sized objects responsible for the lunar mare basins. Scaling upward from the observed number of lunar basins for the greater capture cross-section and impact velocity of the earth indicates that at least 50% of an original global crust would have been converted to basin topography. These basins were flooded by basaltic liquids in times short compared to the isostatic adjustment time for the basin. The modern crustal dichotomy (60% oceanic, 40% continental crust) was established early in the history of the earth, making possible the later onset of plate tectonic processes. These later processes have subsequently reworked, in several cycles, principally the oceanic parts of the earth's crust, changing the configuration of the continents in the process. Ocean basins (and oceans themselves) may be rare occurrences on planets in other star systems.

  13. Origin of the earth's ocean basins

    NASA Technical Reports Server (NTRS)

    Frex, H.

    1977-01-01

    The earth's original ocean basins were mare-type basins produced 4 billion years ago by the flux of asteroid-sized objects responsible for the lunar mare basins. Scaling upwards from the observed number of lunar basins for the greater capture cross-section and impact velocity of the Earth indicates that at least 50 percent of an original global crust would have been converted to basin topography. These basins were flooded by basaltic liquids in times short compared to the isostatic adjustment time for the basin. The modern crustal dichotomy (60 percent oceanic, 40 percent continental crust) was established early in the history of the earth, making possible the later onset of plate tectonic processes. These later processes have subsequently reworked, in several cycles, principally the oceanic parts of the earth's crust, changing the configuration of the continents in the process. Ocean basins (and oceans themselves) may be rare occurrences on planets in other star systems.

  14. H-Area Seepage Basins

    SciTech Connect

    Stejskal, G.

    1990-12-01

    During the third quarter of 1990 the wells which make up the H-Area Seepage Basins (H-HWMF) monitoring network were sampled. Laboratory analyses were performed to measure levels of hazardous constituents, indicator parameters, tritium, nonvolatile beta, and gross alpha. A Gas Chromatograph Mass Spectrometer (GCMS) scan was performed on all wells sampled to determine any hazardous organic constituents present in the groundwater. The primary contaminants observed at wells monitoring the H-Area Seepage Basins are tritium, nitrate, mercury, gross alpha, nonvolatile beta, trichloroethylene (TCE), tetrachloroethylene, lead, cadmium, arsenic, and total radium.

  15. 77 FR 45653 - Yakima River Basin Conservation Advisory Group; Yakima River Basin Water Enhancement Project...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-01

    ... Conservation Advisory Group; Yakima River Basin Water Enhancement Project, Yakima, WA AGENCY: Bureau of... Committee Act, the Yakima River Basin Conservation Advisory Group, Yakima River Basin Water Enhancement... River Basin Water Conservation Program. DATES: The meeting will be held on Tuesday, August 21,...

  16. Caribbean basin framework, 4: Maracaibo basin, northwestern Venezuela

    SciTech Connect

    Lugo, J. )

    1991-03-01

    The Maracaibo basin is presently located in a topographic depression on the Maracaibo block, a triangular, fault-bounded block within the Caribbean-South America plate boundary of northwestern Venezuela. Intense oil exploration over the last 50 years has produced a large amount of seismic and well data that can be used to constrain four Jurassic to Recent tectonic and depositional events that affected the region: (1). Late Jurassic rift phase and subsidence along normal faults striking north-northeast across the floor of the basin; (2) Cretaceous to early Eocene subsidence recorded by shallow to deep marine carbonate and clastic rocks that thicken from south to north and completely cover Permian rocks of the Merida arch; (3) Eocene folding, thrusting, and initial reactivation of Jurassic normal faults as convergent strike-slip and reverse faults. Eocene clastic sediments are thickest in a narrow northwest-trending foredeep on the northeastern margin of the basin; (4) Late Miocene to Recent northwest-southeast convergence is marked by continued reactivation of Jurassic normal faults as reverse and left-lateral strike-slip faults, uplift of mountain ranges bordering the basin, and deposition of up to 10 km of clastic sediment.

  17. IMPROVEMENTS IN PUMP INTAKE BASIN DESIGN

    EPA Science Inventory

    Pump intake basins (or wet wells or pump sumps) designed in accordance with accepted criteria often pose many operation and maintenance problems. The report summarizes field surveys of three trench-type pump intake basins representative of 29 such basins that have been in satisfa...

  18. Supplementary information on K-Basin sludges

    SciTech Connect

    MAKENAS, B.J.

    1999-03-15

    Three previous documents in this series have been published covering the analysis of: K East Basin Floor and Pit Sludge, K East Basin Canister Sludge, and K West Basin Canister Sludge. Since their publication, additional data have been acquired and analyses performed. It is the purpose of this volume to summarize the additional insights gained in the interim time period.

  19. Colby Fire over LA Basin

    Atmospheric Science Data Center

    2014-05-15

    ... Los Angeles Basin, prompting an air quality alert by public health officials. The Multi-angle Imaging SpectroRadiometer (MISR) instrument ... Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Science Mission Directorate, Washington, D.C. The Terra spacecraft is managed ...

  20. BASIN: Beowulf Analysis Symbolic INterface

    NASA Astrophysics Data System (ADS)

    Vesperini, Enrico; Goldberg, David M.; McMillan, Stephen L. W.; Dura, James; Jones, Douglas

    2013-08-01

    BASIN (Beowulf Analysis Symbolic INterface) is a flexible, integrated suite of tools for multiuser parallel data analysis and visualization that allows researchers to harness the power of Beowulf PC clusters and multi-processor machines without necessarily being experts in parallel programming. It also includes general tools for data distribution and parallel operations on distributed data for developing libraries for specific tasks.

  1. Tectonic development of Michigan basin

    SciTech Connect

    Prouty, C.E.

    1986-08-01

    The general form of the Michigan basin and surrounding frame structures - the Findlay, Kankakee, and Wisconsin arches - was inherited from the Precambrian. An ongoing study has provided new information on present basin configuration and the evolution of intrabasinal structures during the Paleozoic. This study involves: (1) isopach, structure contour, depocenter, and lithofacies map preparation; (2) diagenetic and epigenetic dolomitization processes and patterns; (3) Landsat imagery and lineament interpretation; (4) recognition of shearing mechanics and the resulting shear faulting and folding; and (5) the recognition of radial faults in contrast to shear faults. Monitoring of the above throughout the Paleozoic indicates that tectonic events within the basin were episodic in nature. Stresses are recognized as external and, through Fourier analysis of lineaments (shear faults), may be demonstrated as from the southeast, probably the Appalachian mobile belt. Shear faults are seated in Precambrian rocks, although they are probably not of that age. The faults occur with accompanying shear folds in rocks possibly as early as the Late Ordovician or Middle Silurian, but definitely by the Middle Devonian with the principal faulting and folding during the post-Osage Mississippian. Local shifting of the depocenter within the general Saginaw Bay area occurred during the early Paleozoic with a major shift westward to the present central basin position accompanied by the development of the present north-northwest ellipticity of the basin during the post-Osage, pre-Meramecian Mississippian. Barrier separation of the West Michigan Lagoon occurred in the Middle Ordovician and Middle and Late Devonian. Radial structures can be demonstrated in at least the Upper Silurian and Upper Devonian.

  2. Predicting the Eastern Mediterranean Basin

    NASA Astrophysics Data System (ADS)

    Royden, L.

    2011-12-01

    From ~30 Ma onwards, the evolution of the Mediterranean region has been dominated by the rapid migration of thin-skinned thrust-belts. Thrust belt migration has been accommodated by the opening of "back arc type" basins within the upper plate of the thrust belts. Migration of these thrust belts is associated with the migration of subduction systems where subduction and thrusting are driven largely by negative slab buoyancy. Where the subducting slab has large negative buoyancy, thrust belt migration is commonly rapid. Where buoyant continental lithosphere enters the subduction system, subduction ceases quickly. Hence the large-scale tectonic evolution of the Mediterranean basin is largely pre-conditioned by its paleogeography. This can be quantitatively illustrated for the Hellenic subduction system where the post Eocene evolution of the Hellenic thrust belt can be ascribed to the buoyancy of the lithosphere subducted. Entry of the Ionian oceanic lithosphere into a slow-moving trench at 10-15 Ma explains the increase in subduction rate along the central part of the trench, to ~35 mm/yr at present, while subduction rates along strike to the northeast, where continental/transitional crust is subducted, remain less than ~10 mm/yr. Using quantitative modeling of the Hellenic subduction system in post Eocene time, it is possible to approximate how this thrust belt, and the active subduction belt of the eastern Mediterranean, will evolve over the next 10 m.y. This exercise suggests that the large-scale evolution of the eastern Mediterranean basin will be strikingly similar to that of the western Mediterranean basin from 20-0 Ma. This highlights the common dynamic mechanism that shapes the large scale deformation and morphology of the Mediterranean basin.

  3. Automated basin delineation from digital terrain data

    NASA Technical Reports Server (NTRS)

    Marks, D.; Dozier, J.; Frew, J.

    1983-01-01

    While digital terrain grids are now in wide use, accurate delineation of drainage basins from these data is difficult to efficiently automate. A recursive order N solution to this problem is presented. The algorithm is fast because no point in the basin is checked more than once, and no points outside the basin are considered. Two applications for terrain analysis and one for remote sensing are given to illustrate the method, on a basin with high relief in the Sierra Nevada. This technique for automated basin delineation will enhance the utility of digital terrain analysis for hydrologic modeling and remote sensing.

  4. Mississippian facies relationships, eastern Anadarko basin, Oklahoma

    SciTech Connect

    Peace, H.W. ); Forgotson, J.M. )

    1991-08-01

    Mississippian strata in the eastern Anadarko basin record a gradual deepening of the basin. Late and post-Mississippian tectonism (Wichita and Arbuckle orogenies) fragmented the single large basin into the series of paired basins and uplifts recognized in the southern half of Oklahoma today. Lower Mississippian isopach and facies trends (Sycamore and Caney Formations) indicate that basinal strike in the study area (southeastern Anadarko basin) was predominantly east-west. Depositional environment interpretations made for Lower Mississippian strata suggest that the basin was partially sediment starved and exhibited a low shelf-to-basin gradient. Upper Mississippian isopach and facies trends suggest that basinal strike within the study area shifted from dominantly east-west to dominantly northwest-southeast due to Late Mississippian and Early Pennsylvanian uplift along the Nemaha ridge. Within the study area, the Chester Formation, composed of gray to dove-gray shales with interbedded limestones deposited on a carbonate shelf, thins depositionally into the basin and is thinnest at its facies boundary with the Springer Group and the upper portion of the Caney Formation. As basin subsidence rates accelerated, the southern edge of the Chester carbonate shelf was progressively drowned, causing a backstepping of the Chester Formation calcareous shale and carbonate facies. Springer Group sands and black shales transgressed northward over the drowned Chester Formation shelf.

  5. Geodynamics of the Sivas Basin (Turkey): from a forearc basin to a retroarc foreland basin

    NASA Astrophysics Data System (ADS)

    Legeay, Etienne; Ringenbach, Jean-Claude; Kergaravat, Charlie; Callot, Jean-Paul; Mohn, Geoffroy; Kavak, Kaan

    2016-04-01

    Anatolia records the consumption of several oceanic basins, from the Northern Neotethys domain, by north-dipping subduction until the end of Mesozoic. The associated obduction event occurred during Campanian, from North to South and from Greece to Oman, leading to the emplacement of ophiolite thrust sheets and associated ophiolitic mélange. In particular, the Sivas Basin in Eastern Anatolia is located at the boundary between the Kırsehir block to the East, Pontide arc to the North and Tauride Platform to the South, sutured by ophiolitic belts. The Sivas Basin formed a Tertiary fold-and-thrust belt, which exhibits mainly north verging thrust in Paleogene deposits, and South verging thrust in oligo-miocene sequence. To understand the northern verging thrust above south verging obduction, it is necessary to zoom out of the basin, and include a set of processes that affect the eastern Anatolia. This study aims to characterize the structural and sedimentary evolution of the Sivas Basin, based on a fieldwork approach, coupled to the interpretation of subsurface data, thermochronology and biostratigraphy. The Sivas Basin was initiated in a forearc setting relatively to the subduction of the Inner-Tauride Ocean while the associated ophiolites are obducted onto the northern passive margin of the Tauride margin. Early Maastrichtian to Paleocene deposits are represented by carbonate platforms located on ophiolitic highs, passing to turbidites and olistostomes toward the North. The early Eocene sediments, mainly composed of ophiolitic clasts, are deposited on a regional unconformity marked along the southern margin of the basin by incisions in response to the emergence of north-verging thrust. The middle Eocene sediments, intensively folded by northward thrusting, are mostly represented by flysch type deposits (olistostromes, mass-flows and turbidites). The onset of the compression is related to the initiation of the Taurus shortening in a retroarc situation, in response to

  6. Formation of lunar basin rings

    USGS Publications Warehouse

    Hodges, C.A.; Wilhelms, D.E.

    1978-01-01

    The origin of the multiple concentric rings that characterize lunar impact basins, and the probable depth and diameter of the transient crater have been widely debated. As an alternative to prevailing "megaterrace" hypotheses, we propose that the outer scarps or mountain rings that delineate the topographic rims of basins-the Cordilleran at Orientale, the Apennine at Imbrium, and the Altai at Nectaris-define the transient cavities, enlarged relatively little by slumping, and thus are analogous to the rim crests of craters like Copernicus; inner rings are uplifted rims of craters nested within the transient cavity. The magnitude of slumping that occurs on all scarps is insufficient to produce major inner rings from the outer. These conclusions are based largely on the observed gradational sequence in lunar central uplifts:. from simple peaks through somewhat annular clusters of peaks, peak and ring combinations and double ring basins, culminating in multiring structures that may also include peaks. In contrast, belts of slump terraces are not gradational with inner rings. Terrestrial analogs suggest two possible mechanisms for producing rings. In some cases, peaks may expand into rings as material is ejected from their cores, as apparently occurred at Gosses Bluff, Australia. A second process, differential excavation of lithologically diverse layers, has produced nested experimental craters and is, we suspect, instrumental in the formation of terrestrial ringed impact craters. Peak expansion could produce double-ring structures in homogeneous materials, but differential excavation is probably required to produce multiring and peak-in-ring configurations in large lunar impact structures. Our interpretation of the representative lunar multiring basin Orientale is consistent with formation of three rings in three layers detected seismically in part of the Moon-the Cordillera (basin-bounding) ring in the upper crust, the composite Montes Rook ring in the underlying

  7. THE ADVANCED CHEMISTRY BASINS PROJECT

    SciTech Connect

    William Goddard; Peter Meulbroek; Yongchun Tang; Lawrence Cathles III

    2004-04-05

    In the next decades, oil exploration by majors and independents will increasingly be in remote, inaccessible areas, or in areas where there has been extensive shallow exploration but deeper exploration potential may remain; areas where the collection of data is expensive, difficult, or even impossible, and where the most efficient use of existing data can drive the economics of the target. The ability to read hydrocarbon chemistry in terms of subsurface migration processes by relating it to the evolution of the basin and fluid migration is perhaps the single technological capability that could most improve our ability to explore effectively because it would allow us to use a vast store of existing or easily collected chemical data to determine the major migration pathways in a basin and to determine if there is deep exploration potential. To this end a the DOE funded a joint effort between California Institute of Technology, Cornell University, and GeoGroup Inc. to assemble a representative set of maturity and maturation kinetic models and develop an advanced basin model able to predict the chemistry of hydrocarbons in a basin from this input data. The four year project is now completed and has produced set of public domain maturity indicator and maturation kinetic data set, an oil chemistry and flash calculation tool operable under Excel, and a user friendly, graphically intuitive basin model that uses this data and flash tool, operates on a PC, and simulates hydrocarbon generation and migration and the chemical changes that can occur during migration (such as phase separation and gas washing). The DOE Advanced Chemistry Basin Model includes a number of new methods that represent advances over current technology. The model is built around the concept of handling arbitrarily detailed chemical composition of fluids in a robust finite-element 2-D grid. There are three themes on which the model focuses: chemical kinetic and equilibrium reaction parameters, chemical

  8. The Central European Permian Basins; Rheological and structural controls on basin history and on inter-basin connectivity

    NASA Astrophysics Data System (ADS)

    Smit, Jeroen; Van Wees, Jan-Diederik; Cloetingh, Sierd

    2014-05-01

    We analyse the relative importance of the major crustal-scale fault zones and crustal architecture in controlling basin formation, deformation and the structural connections between basins. The North and South Permian Basins of Central Europe are usually defined by the extend of Rotliegend sedimentary and volcanic units and not by a common tectonic origin or development. Instead, the sub-basins that together form the Permian Basins are each controlled by different structural and/or rheological controls that are inherited from Early Paleozoïc and older geodynamic processes, they are even located in different crustal/lithospheric domains. The North Permian basin is located on Baltic crust that was thinned during Late Proterozoïc - Early Paleozoïc times. South of the Thor suture, the South Permian basin and its sub-basins are located on Avalonian crust (Southern North Sea and North German Basins) and on the transition of East European cratonic and Avalonian crust (Polish Through). The size of crustal domains and of the faults that govern basin formation requires a regional-scale to assess their impact on basins and sub-basins. In the case of the Permian Basins this encompasses East Avalonia and surroundings, roughly speaking the area north of the Variscan Rheïc suture, east of the Atlantic and southwest of the Teisseyre-Tornquist line. This approach sheds light on the effects of long lived differences in crustal fabric which are responsible for spatial heterogeneity in stress and strain magnitudes and zonations of fracturing, burial history and temperature history. The focus on understanding the geomechanical control of large crustal-scale fault structures will provide the constraints and geometrical and compositional input for local models of stress and strain. Considering their fundamentally different structural and rheological controls, the Permian (sub)basins have a remarkably common history of subsidence and inversion, suggesting a more or less continuous

  9. Geology of interior cratonic sag basins

    SciTech Connect

    Leighton, M.W.; Eidel, J.J.; Kolata, D.R.; Oltz, D.F. )

    1990-05-01

    Interior cratonic sag basins are thick accumulations of sediment, generally more or less oval in shape, located entirely in the interiors of continental masses. Some are single-cycle basins and others are characterized by repeated sag cycles or are complex polyhistory basins. Many appear to have developed over ancient rift systems. Interior cratonic sag basins are typified by a dominance of flexural over fault-controlled subsidence, and a low ratio of sediment volume to surface area of the basin. The Baltic, Carpentaria, Illinois, Michigan, Parana, Paris, and Williston basins are examples of interior cratonic sag basins. Tectonics played a dominant role in controlling the shapes and the geometries of the juxtaposed packets of sedimentary sequences. While the mechanics of tectonic control are not clear, evidence suggests that the movements are apparently related to convergence of lithospheric plates and collision and breakup of continents. Whatever the cause, tectonic movements controlled the freeboard of continents, altering base level and initiating new tectono-sedimentologic regimes. Sag basins situated in low latitudes during their development commonly were sites of thick carbonates (e.g., Illinois, Michigan, Williston, and Paris basins). In contrast, siliciclastic sedimentation characterized basins that formed in higher latitudes (e.g., Parana and Carpentaria basins). Highly productive sag basins are characterized by widespread, mature, organic-rich source rocks, large structures, and good seals. Nonproductive basins have one or more of the following characteristics: immature source rocks, leaky plumbing, freshwater flushing, and/or complex geology due to numerous intrusions that inhibit mapping of plays.

  10. Tectonic classification of Cenozoic Iberian foreland basins

    NASA Astrophysics Data System (ADS)

    De Vicente, G.; Cloetingh, S.; Van Wees, J. D.; Cunha, P. P.

    2011-04-01

    The Iberian microcontinent stands out because of its intense Alpine intraplate deformation. This is reflected in a large number of Cenozoic basins of very different sizes. Most of the contacts between topographic highs and basins are thrust or strike-slip faults. All these basins seem to have undergone a common sedimentary evolution, comprising four stages: initiation of sedimentation, intense syn-tectonic infilling, change from endorheic to exorheic drainage, and accelerated erosion related to fluvial incision. This simple evolutionary model shows a migration from East to West, in which basins are still tectonically active at the Atlantic margin of Iberia. This common evolution is also found in a series of geometrical characteristics, such as the ratio r of length of strike-slip fault and length of thrust fault, that are very similar in both types of basin border settings. Thrust-related basins are mainly associated with segmented pop-downs, whereas the main basins have the characteristics of open-ramp basins. Strike-slip related basins are mostly transpressive structures, although small pull-apart basins are usual along the Vilariça and Messejana faults. For basin areas larger than 100-1000 km 2, a constant r value of 0.6 is found (including the Ebro, Duero, Madrid, Lower Tagus and Badajoz basins). Within the Iberian microcontinent, the total amount of Cenozoic contractional deformation was distributed between strike-slip and thrust faults with an r ratio close to 0.6. However, for small basins this parameter seems to depend on the type of fault, range or deformation belt (pure strike-slip, transtension, transpression, and pop-up) independently of its local tectonic development.

  11. CLEAR LAKE BASIN 2000 PROJECT

    SciTech Connect

    LAKE COUNTY SANITATION DISTRICT

    2003-03-31

    The following is a final report for the Clear Lake Basin 2000 project. All of the major project construction work was complete and this phase generally included final details and testing. Most of the work was electrical. Erosion control activities were underway to prepare for the rainy season. System testing including pump stations, electrical and computer control systems was conducted. Most of the project focus from November onward was completing punch list items.

  12. Biogeochemistry of a Suburban Basin

    NASA Astrophysics Data System (ADS)

    McDowell, W. H.; Daley, M. L.; Blumberg, J.

    2002-12-01

    A long-term research effort was recently established in the Lamprey River basin in southeastern New Hampshire. The watershed is largely forested, and has significant amounts of wetlands due to the relatively low topographic relief. Human population growth is rapid, resulting in conversion of forest and agricultural land to housing tracts. The primary focus of the project will be to examine the relationships between land use, land cover and water quality as the watershed continues to increase in population density. A secondary emphasis will be to examine the interactions between hydrologic flow paths, climatic variability, and biogeochemical processes that drive groundwater and surface water quality in the basin. Our initial work has quantified landscape attributes and related them to water quality. Results to date show that small tributary streams are relatively high in nitrogen relative to the main stem of the Lamprey; that human population density drives nitrate concentrations in the basin; and that DOC flux is predicted well by the model of Aitkenhead and McDowell that links DOC flux to watershed C:N ratio.

  13. Great Basin geoscience data base

    USGS Publications Warehouse

    Raines, Gary L.; Sawatzky, Don L.; Connors, Katherine A.

    1996-01-01

    This CD-ROM serves as the archive for 73 digital GIS data set for the Great Basin. The data sets cover Nevada, eastern California, southeastern Oregon, southern Idaho, and western Utah. Some of the data sets are incomplete for the total area. On the CD-ROM, the data are provided in three formats, a prototype Federal Data Exchange standard format, the ESRI PC ARCVIEW1 format for viewing the data, and the ESRI ARC/INFO export format. Extensive documentation is provided to describe the data, the sources, and data enhancements. The following data are provided. One group of coverages comes primarily from 1:2,000,000-scale National Atlas data and can be assembled for use as base maps. These various forms of topographic information. In addition, public land system data sets are provided from the 1:2,500,000-scale Geologic Map of the United States and 1:500,000-scale geologic maps of Nevada, Oregon, and Utah. Geochemical data from the National Uranium Resource Evaluation (NURE) program are provided for most of the Great Basin. Geophysical data are provided for most of the Great Basin, typically gridded data with a spacing of 1 km. The geophysical data sets include aeromagnetics, gravity, radiometric data, and several derivative products. The thematic data sets include geochronology, calderas, pluvial lakes, tectonic extension domains, distribution of pre-Cenozoic terranes, limonite anomalies, Landsat linear features, mineral sites, and Bureau of Land Management exploration and mining permits.

  14. The geologic history of Margaritifer basin, Mars

    NASA Astrophysics Data System (ADS)

    Salvatore, M. R.; Kraft, M. D.; Edwards, C. S.; Christensen, P. R.

    2016-03-01

    In this study, we investigate the fluvial, sedimentary, and volcanic history of Margaritifer basin and the Uzboi-Ladon-Morava outflow channel system. This network of valleys and basins spans more than 8000 km in length, linking the fluvially dissected southern highlands and Argyre basin with the northern lowlands via Ares Vallis. Compositionally, thermophysically, and morphologically distinct geologic units are identified and are used to place critical relative stratigraphic constraints on the timing of geologic processes in Margaritifer basin. Our analyses show that fluvial activity was separated in time by significant episodes of geologic activity, including the widespread volcanic resurfacing of Margaritifer basin and the formation of chaos terrain. The most recent fluvial activity within Margaritifer basin appears to terminate at a region of chaos terrain, suggesting possible communication between surface and subsurface water reservoirs. We conclude with a discussion of the implications of these observations on our current knowledge of Martian hydrologic evolution in this important region.

  15. The geologic history of Margaritifer basin, Mars

    USGS Publications Warehouse

    Salvatore, M. R.; Kraft, M. D.; Edwards, Christopher; Christensen, P.R.

    2016-01-01

    In this study, we investigate the fluvial, sedimentary, and volcanic history of Margaritifer basin and the Uzboi-Ladon-Morava (ULM) outflow channel system. This network of valleys and basins spans more than 8000 km in length, linking the fluvially dissected southern highlands and Argyre Basin with the northern lowlands via Ares Vallis. Compositionally, thermophysically, and morphologically distinct geologic units are identified and are used to place critical relative stratigraphic constraints on the timing of geologic processes in Margaritifer basin. Our analyses show that fluvial activity was separated in time by significant episodes of geologic activity, including the widespread volcanic resurfacing of Margaritifer basin and the formation of chaos terrain. The most recent fluvial activity within Margaritifer basin appears to terminate at a region of chaos terrain, suggesting possible communication between surface and subsurface water reservoirs. We conclude with a discussion of the implications of these observations on our current knowledge of Martian hydrologic evolution in this important region.

  16. Biological science in the Great Basin

    USGS Publications Warehouse

    ,

    2005-01-01

    The Great Basin is an expanse of desert and high moun-tains situated between the Rocky Mountains and the Sierra Nevada of the western United States. The most explicit description of the Great Basin is that area in the West where surface waters drain inland. In other words, the Great Basin is comprised of many separate drainage areas - each with no outlet. What at first glance may appear as only a barren landscape, the Great Basin upon closer inspection reveals island mountains, sagebrush seas, and intermittent aquatic habitats, all teeming with an incredible number and variety of plants and animals. Biologists at the USGS are studying many different species and ecosystems in the Great Basin in order to provide information about this landscape for policy and land-management decision-making. The following stories represent a few of the many projects the USGS is conducting in the Great Basin.

  17. Thermal evolution of sedimentary basins in Alaska

    USGS Publications Warehouse

    Johnsson, Mark J.; Howell, D.G.

    1996-01-01

    The complex tectonic collage of Alaska is reflected in the conjunction of rocks of widely varying thermal maturity. Indicators of the level of thermal maturity of rocks exposed at the surface, such as vitrinite reflectance and conodont color alteration index, can help constrain the tectonic evolution of such complex regions and, when combined with petrographic, modern heat flow, thermogeochronologic, and isotopic data, allow for the detailed evaluation of a region?s burial and uplift history. We have collected and assembled nearly 10,000 vitrinite-reflectance and conodont-color-alteration index values from the literature, previous U.S. Geological Survey investigations, and our own studies in Alaska. This database allows for the first synthesis of thermal maturity on a broadly regional scale. Post-accretionary sedimentary basins in Alaska show wide variability in terms of thermal maturity. The Tertiary interior basins, as well as some of the forearc and backarc basins associated with the Aleutian Arc, are presently at their greatest depth of burial, with immature rocks exposed at the surface. Other basins, such as some backarc basins on the Alaska Peninsula, show higher thermal maturities, indicating modest uplift, perhaps in conjunction with higher geothermal gradients related to the arc itself. Cretaceous ?flysch? basins, such as the Yukon-Koyukuk basin, are at much higher thermal maturity, reflecting great amounts of uplift perhaps associated with compressional regimes generated through terrane accretion. Many sedimentary basins in Alaska, such as the Yukon-Koyukuk and Colville basins, show higher thermal maturity at basin margins, perhaps reflecting greater uplift of the margins in response to isostatic unloading, owing to erosion of the hinterland adjacent to the basin or to compressional stresses adjacent to basin margins.

  18. Reserves in western basins: Part 1, Greater Green River basin

    SciTech Connect

    Not Available

    1993-10-01

    This study characterizes an extremely large gas resource located in low permeability, overpressured sandstone reservoirs located below 8,000 feet drill depth in the Greater Green River basin, Wyoming. Total in place resource is estimated at 1,968 Tcf. Via application of geologic, engineering and economic criteria, the portion of this resource potentially recoverable as reserves is estimated. Those volumes estimated include probable, possible and potential categories and total 33 Tcf as a mean estimate of recoverable gas for all plays considered in the basin. Five plays (formations) were included in this study and each was separately analyzed in terms of its overpressured, tight gas resource, established productive characteristics and future reserves potential based on a constant $2/Mcf wellhead gas price scenario. A scheme has been developed to break the overall resource estimate down into components that can be considered as differing technical and economic challenges that must be overcome in order to exploit such resources: in other words, to convert those resources to economically recoverable reserves. Total recoverable reserves estimates of 33 Tcf do not include the existing production from overpressured tight reservoirs in the basin. These have estimated ultimate recovery of approximately 1.6 Tcf, or a per well average recovery of 2.3 Bcf. Due to the fact that considerable pay thicknesses can be present, wells can be economic despite limited drainage areas. It is typical for significant bypassed gas to be present at inter-well locations because drainage areas are commonly less than regulatory well spacing requirements.

  19. Reserve estimates in western basins. Part 2: Piceance Basin

    SciTech Connect

    1995-10-01

    This study characterizes an extremely large gas resource located in low permeability, sandstone reservoirs of the Mesaverde group in the Piceance Basin, Colorado. Total in place resource is estimated at 307.3 Tcf. Via application of geologic, engineering and economic criteria, the portion of this resource potentially recoverable as reserves is estimated. Those volumes estimated include probable, possible and potential categories and total 5.8 Tcf as a mean estimate of recoverable gas for all plays considered in the basin. About 82.6% of the total evaluated resource is contained within sandstones that have extremely poor reservoir properties with permeabilities considered too low for commerciality using current frac technology. Cost reductions and technology improvements will be required to unlock portions of this enormous resource. Approximately 2.7% of the total resource is contained within sandstone reservoirs which do not respond to massive hydraulic fracture treatments, probably due to their natural lenticular nature. Approximately 6.8% of the total resource is located in deeply buried settings below deepest established production. Approximately 7.9% of the total resource is considered to represent tight reservoirs that may be commercially exploited using today`s hydraulic fracturing technology. Recent technology advances in hydraulic fracturing practices in the Piceance Basin Mesaverde has resulted in a marked improvement in per well gas recovery which, where demonstrated, has been incorporated into the estimates provided in this report. This improvement is so significant in changing the risk-reward relationship that has historically characterized this play, that previously uneconomic areas and resources will graduate to the economically exploitable category. 48 refs., 96 figs., 18 tabs.

  20. Petroleum system of the Gippsland Basin, Australia

    USGS Publications Warehouse

    Bishop, Michele G.

    2000-01-01

    The Gippsland Basin Province 3930, located on the southeastern coast of Australia, is formed from two successive failed rifts that developed into a passive margin during the Cretaceous. Formation of this basin is related to the break up of Gondwana, which resulted in the separation of Antarctica from Australia, and the separation of the New Zealand and Lord Howe Rise continental crust from Australia. Coals and coaly shales of Late Cretaceous through Eocene age are the source rocks for oil and gas that accumulated predominantly in anticlinal traps. The basin was Australia?s major producing basin until 1996 when daily oil/condensate production from the North West Shelf surpassed it.

  1. Late Paleozoic structural evolution of Permian basin

    SciTech Connect

    Ewing, T.E.

    1984-04-01

    The southern Permian basin is underlain by the NNW-trending Central Basin disturbed belt of Wolfcamp age (Lower Permian), the deep Delaware basin to its west, and the shallower Midland basin to its eat. The disturbed belt is highly segmented with zones of left-lateral offset. Major segments from south to north are: the Puckett-Grey Ranch zone; the Fort Stockton uplift; the Monahans transverse zone; the Andector ridges and the Eunice ridge; the Hobbs transverse zone; and the Tatum ridges, which abut the broad Roosevelt uplift to the north. The disturbed belt may have originated along rift zones of either Precambrian or Cambrian age. The extent of Lower and Middle Pennsylvanian deformation is unclear; much of the Val Verde basin-Ozona arch structure may have formed then. The main Wolfcamp deformation over thrust the West Texas crustal block against the Delaware block, with local denudation of the uplifted edge and eastward-directed backthrusting into the Midland basin. Latter in the Permian, the area was the center of a subcontinental bowl of subsidence - the Permian basin proper. The disturbed belt formed a pedestal for the carbonate accumulations which created the Central Basin platform. The major pre-Permian reservoirs of the Permian basin lie in large structural and unconformity-bounded traps on uplift ridges and domes. Further work on the regional structural style may help to predict fracture trends, to assess the timing of oil migration, and to evaluate intrareservoir variations in the overlying Permian giant oil fields.

  2. Basin Management under the Global Climate Change (Take North-East Asia Heilongjiang -Amur Basin and Taihu Basin For Example)

    NASA Astrophysics Data System (ADS)

    Liu, S.; Zhou, Z.; Zhong, G.; Zhang, X.

    2015-12-01

    The impact of global climate change on environment and society causes increasingly concern in different countries around the world. The main climate characteristic values, such as precipitation and temperature, have been changed, which leads to the variation of water resources, especially in large basins. Heilongjiang-Amur Basin and Taihu Basin are two large and important basins in China with large area and population. As global climate change and human activities have siganificant impacts on hydrology and water resources in two basins, the analysis of climate change are of great value. In this study, in Heilongjiang-Amur Basin, precipitation and temperature are investigated and their variation are predicted. And in Taihu Basin, precipitation including plum rain and typhoon, are studied and the variation trend of precipitation is predicted. Hence, the impacts of global climate change are assessed. From the result, it shows that the average temperature will continue to increase, and the precipitation will reduce first and then turn to increase in these two basins. It demonstrates that the water resources have been affected a lot by climate change as well as human activities. And these conclusions are provided as reference for policy makers and basin authorities in water resources management and natural hazards mitigation. Meanwhile, according to basins' particualr characters, the suggestions to future water resources management in two basins are given, and more scientific, comprehensive and sustained managements are required. Especially, in Heilongjiang-Amur River, which is a boundary river between China and Russia, it is very essential to enhance the cooperation between two countries.

  3. 75 FR 43915 - Basin Electric Power Cooperative: Deer Creek Station

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-27

    ... Rural Utilities Service Basin Electric Power Cooperative: Deer Creek Station AGENCY: Rural Utilities... CFR Part 1794), and the Western Area Power Administration's (Western) NEPA implementing regulations... environmental impacts of and alternatives to Basin Electric Power Cooperative's (Basin Electric) application...

  4. Seismic Characterization of the Jakarta Basin

    NASA Astrophysics Data System (ADS)

    Cipta, A.; Saygin, E.; Cummins, P. R.; Masturyono, M.; Rudyanto, A.; Irsyam, M.

    2015-12-01

    Jakarta, Indonesia, is home to more than 10 million people. Many of these people live in seismically non-resilient structures in an area that historical records suggest is prone to earthquake shaking. The city lies in a sedimentary basin composed of Quaternary alluvium that experiences rapid subsidence (26 cm/year) due to groundwater extraction. Forecasts of how much subsidence may occur in the future are dependent on the thickness of the basin. However, basin geometry and sediment thickness are poorly known. In term of seismic hazard, thick loose sediment can lead to high amplification of seismic waves, of the kind that led to widespread damage in Mexico city during the Michoacan Earthquake of 1985. In order to characterize basin structure, a temporary seismograph deployment was undertaken in Jakarta in Oct 2013- Jan 2014. A total of 96 seismic instrument were deployed throughout Jakarta were deployed throughout Jakarta at 3-5 km spacing. Ambient noise tomography was applied to obtain models of the subsurface velocity structure. Important key, low velocity anomalies at short period (<8s) correspond to the main sedimentary sub-basins thought to be present based on geological interpretations of shallow stratigraphy in the Jakarta Basin. The result shows that at a depth of 300 m, shear-wave velocity in the northern part (600 m/s) of the basin is lower than that in the southern part. The most prominent low velocity structure appears in the northwest of the basin, down to a depth of 800 m, with velocity as low as 1200 m/s. This very low velocity indicates the thickness of sediment and the variability of basin geometry. Waveform computation using SPECFEM2D shows that amplification due to basin geometry occurs at the basin edge and the thick sediment leads to amplification at the basin center. Computation also shows the longer shaking duration occurrs at the basin edge and center of the basin. The nest step will be validating the basin model using earthquake events

  5. Cenozoic evolution of San Joaquin basin, California

    SciTech Connect

    Bartow, J.A.

    1988-03-01

    The Neogene San Joaquin basin in the southern part of the 700-km long Great Valley of California is a successor to a late Mesozoic and earliest Tertiary forearc basin. The transition from forearc basin to the more restricted Neogene marine basin occurred principally during the Paleogene as the plate tectonic setting changed from oblique convergence to normal convergence, and finally to the initiation of tangential (transform) movement near the end of the Oligocene. Regional-scale tectonic events that affected the basin include: (1) clockwise rotation of the southernmost Sierra Nevada, and large-scale en echelon folding in the southern Diablo Range, both perhaps related to Late Cretaceous and early Tertiary right slip on the proto-San-Andreas fault; (2) regional uplift of southern California in the Oligocene that resulted from the subduction of the Pacific-Farallon spreading ridge: (3) extensional tectonism in the Basin and Range province, particularly in the Miocene; (4) wrench tectonism adjacent to the San Andreas fault in the Neogene; (5) northeastward emplacement of a wedge of the Franciscan complex at the west side of the Sierran block, with associated deep-seated thrusting in the late Cenozoic; and (6) the accelerated uplift of the Sierra Nevada beginning in the late Miocene. Neogene basin history was controlled principally by the tectonic effects of the northwestward migration of the Mendocino triple junction along the California continental margin and by the subsequent wrench tectonism associated with the San Andreas fault system. East-west compression in the basin, resulting from extension in the Basin and Range province was an important contributing factor to crustal shortening at the west side of the valley. Analysis of the sedimentary history of the basin, which was controlled to some extent by eustatic sea level change, enables reconstruction of the basin paleogeography through the Cenozoic.

  6. Oil migration pattern in the Sirte Basin

    SciTech Connect

    Roohi, M.; Aburawi, R.M.

    1995-08-01

    Sirte Basin is an asymmetrical cratonic basin, situated in the north-central part of Libya. It covers an area of over 350,000km{sup 2} and is one of the most prolific oil-producing basins in the world. Sirte Basin is divided into large NW-SE trending sub-parallel platforms and troughs bounded by deep seated syndepositional normal faults. A very unique combination of thick sediments with rich source rocks in the troughs vs. thinner sediments with prolific reservoir rocks on the platforms accounts for the productivity of the basin. Analysis of oil migration pattern in the Sirte Basin will certainly help to discover the remaining reserves, and this can only be achieved if the important parameter of structural configuration of the basin at the time of oil migration is known. The present paper is an attempt to analyse the time of oil migration, to define the structural picture of the 4 Basin during the time of migration and to delineate the most probable connecting routes between the hydrocarbon kitchens and the oil fields.

  7. Basin wildrye: the forgotten grass revisited

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Basin wildrye was once a very abundant and widely occurring species throughout the landscapes of northern Nevada. When Captain Simpson, of the topographical Engineers, explored the route for a wagon road across the central Great Basin he marveled at the grass in the valley bottoms that reached to h...

  8. Water quality in the eastern Iowa basins

    USGS Publications Warehouse

    Kalkhoff, Stephen J.; Barnes, Kymm K.; Becher, Kent D.; Savoca, Mark E.; Schnoebelen, Douglas J.; Sadorf, Eric M.; Porter, Stephen D.; Sullivan, Daniel J.; Creswell, John

    2001-01-01

    The Eastern Iowa Basins Study Unit includes the Wapsipinicon, Cedar, Iowa, and Skunk River basins and covers approximately 19,500 square miles in eastern Iowa and southern Minnesota. More than 90 percent of the land in the study unit is used for agricultural purposes. Forested areas account for only 4 percent of the land area.

  9. Frontier sedimentary basins of New Zealand region

    SciTech Connect

    Beggs, J.M. )

    1991-03-01

    Petroleum-prospective basins of New Zealand began to form by mid-Cretaceous rifting of crustal elements previously assembled at the Gondwana continental margin. During the latest Cretaceous-early Cenozoic New Zealand separated from Australia and Antarctica by sea-floor spreading. An overall transgression in widely recorded in this post-rift phase, with decreasing clastic sediment supply as land area and relief were reduced. Mid-Cenozoic initiation of the modern plate boundary has resulted in uplift of mountain ranges, subsidence and filling of troughs, progradation of the shelf, and common reactivation or eversion of older structures. Petroleum potential of less explored basins can be compared to the productive Taranki basin. Source rocks are coal-rich deposits of the rift phase, also developed in Great South, Canterbury/Chatham, Western Southland, West Coast, and Northland basins. A different source contributes to oil and gas seeps on the East Coast, a continental margin during Late Cretaceous. The main reservoirs of Taranaki are early Cenozoic coastal and fluvial sands, also present in Great South, Canterbury, and West Coast and possibly other basins. Other Taranaki reservoirs include mid-Cenozoic limestone and Miocene turbidites, which are widespread in most other basins. Pliocene limestones have excellent reservoir potential on the East Coast. Late Cenozoic tectonics, essential to trap development and significant for maturation in Taranaki, have created similar structures in basins near the plate boundary but are less significant in the development of Great South, eastern Canterbury/Chatham, and Northland basins.

  10. African sedimentary basins - Tectonic controls on prospectivity

    SciTech Connect

    Bunter, M.A.G.; Crossley, R.; Hammill, M.; Jones, P.W.; Morgan, R.K.; Needham, D.T.; Spaargaren, F.A. )

    1991-03-01

    An important prerequisite for the evaluation of any sedimentary basin is the understanding of its regional tectonic setting. This is especially so in the underexplored regions of Africa. The majority of African sedimentary basins developed in an extensional setting although some have undergone subsequent compressional or transpressional deformation. The geometry and evolution of these basins is often influenced by basement structure. The extensional phase of basin development controls not only the distribution of syn-rift sediments but also the magnitude of post-rift regional subsidence and the preservation or removal of pre-rift sediments. This has important consequences for exploration models of syn-rift and pre-rift source rocks and reservoirs. Post-rift basin inversion and uplift provide crucial controls on the preservation of mature source rocks and quality of reservoirs. The distribution, nature, timing, and possible mechanisms of this uplift in Africa will be addressed. The hydrocarbon prospectivity of African basis appears to be highly variable although the limited exploration of some regions makes the exact extent of this variability unclear. Basins considered potentially prospective range from late Precambrian to Tertiary in age. The various tectonic controls outlined above, and criteria for the evaluation of underexplored areas, will be demonstrated by reference to basins studied by The Robertson Group. Examples described include basins from Bagon, Angola, Namibia, East Africa, Tertiary Rift and Karoo Rifts, and North Africa (Sudan, Egypt, Algeria, and Morocco).

  11. Wyoming Basin Rapid Ecoregional Assessment

    USGS Publications Warehouse

    Carr, Natasha B.; Means, Robert E.

    2013-01-01

    The overall goal of the Wyoming Basin Rapid Ecoregional Assessment (REA) is to provide information that supports regional planning and analysis for the management of ecological resources. The REA provides an assessment of baseline ecological conditions, an evaluation of current risks from drivers of ecosystem change (including energy development, fire, and invasive species), and a predictive capacity for evaluating future risks (including climate change). Additionally, the REA may be used for identifying priority areas for conservation or restoration and for assessing cumulative effects of multiple land uses. The Wyoming Basin REA will address Management Questions developed by the Bureau of Land Management and other agency partners for 8 major biomes and 19 species or species assemblages. The maps developed for addressing Management Questions will be integrated into overall maps of landscape-level ecological values and risks. The maps can be used to address the goals of the REA at a number of levels: for individual species, species assemblages, aquatic and terrestrial systems, and for the entire ecoregion. This allows flexibility in how the products of the REA are compiled to inform planning and management actions across a broad range of spatial scales.

  12. Basins in ARC-continental collisions

    USGS Publications Warehouse

    Draut, Amy E.; Clift, Peter D.; Busby, Cathy; Azor, Antonio

    2012-01-01

    Arc-continent collisions occur commonly in the plate-tectonic cycle and result in rapidly formed and rapidly collapsing orogens, often spanning just 5-15 My. Growth of continental masses through arc-continent collision is widely thought to be a major process governing the structural and geochemical evolution of the continental crust over geologic time. Collisions of intra-oceanic arcs with passive continental margins (a situation in which the arc, on the upper plate, faces the continent) involve a substantially different geometry than collisions of intra-oceanic arcs with active continental margins (a situation requiring more than one convergence zone and in which the arc, on the lower plate, backs into the continent), with variable preservation potential for basins in each case. Substantial differences also occur between trench and forearc evolution in tectonically erosive versus tectonically accreting margins, both before and after collision. We examine the evolution of trenches, trench-slope basins, forearc basins, intra-arc basins, and backarc basins during arc-continent collision. The preservation potential of trench-slope basins is low; in collision they are rapidly uplifted and eroded, and at erosive margins they are progressively destroyed by subduction erosion. Post-collisional preservation of trench sediment and trench-slope basins is biased toward margins that were tectonically accreting for a substantial length of time before collision. Forearc basins in erosive margins are usually floored by strong lithosphere and may survive collision with a passive margin, sometimes continuing sedimentation throughout collision and orogeny. The low flexural rigidity of intra-arc basins makes them deep and, if preserved, potentially long records of arc and collisional tectonism. Backarc basins, in contrast, are typically subducted and their sediment either lost or preserved only as fragments in melange sequences. A substantial proportion of the sediment derived from

  13. Rifting Thick Lithosphere - Canning Basin, Western Australia

    NASA Astrophysics Data System (ADS)

    Czarnota, Karol; White, Nicky

    2016-04-01

    The subsidence histories and architecture of most, but not all, rift basins are elegantly explained by extension of ~120 km thick lithosphere followed by thermal re-thickening of the lithospheric mantle to its pre-rift thickness. Although this well-established model underpins most basin analysis, it is unclear whether the model explains the subsidence of rift basins developed over substantially thick lithosphere (as imaged by seismic tomography beneath substantial portions of the continents). The Canning Basin of Western Australia is an example where a rift basin putatively overlies lithosphere ≥180 km thick, imaged using shear wave tomography. Subsidence modelling in this study shows that the entire subsidence history of the <300 km wide and <6 km thick western Canning Basin is adequately explained by mild Ordovician extension (β≈1.2) of ~120 km thick lithosphere followed by post-rift thermal subsidence. This is consistent with the established model, described above, albeit with perturbations due to transient dynamic topography support which are expressed as basin-wide unconformities. In contrast the <150 km wide and ~15 km thick Fitzroy Trough of the eastern Canning Basin reveals an almost continuous period of normal faulting between the Ordovician and Carboniferous (β<2.0) followed by negligible post-rift thermal subsidence. These features cannot be readily explained by the established model of rift basin development. We attribute the difference in basin architecture between the western and eastern Canning Basin to rifting of thick lithosphere beneath the eastern part, verified by the presence of ~20 Ma diamond-bearing lamproites intruded into the basin depocentre. In order to account for the observed subsidence, at standard crustal densities, the lithospheric mantle is required to be depleted in density by 50-70 kg m-3, which is in line with estimates derived from modelling rare-earth element concentrations of the ~20 Ma lamproites and global isostatic

  14. Hydrological research basins and the environment

    NASA Astrophysics Data System (ADS)

    Alley, V. M.; Warmerdam, P. M. M.

    The role and relative importance of experimental and representative basins in pre-dieting anthropogenic effects on water resources and the environment was the goal of the International Conference on Hydrological Research Basins and the Environment, held in Wageningen, the Netherlands, September 24-28, 1990. About 70 persons, almost exclusively from Europe, attended the meeting, which was organized by the Committee of the European Network of Experimental and Representative Basins and the National Committee of the Netherlands for the International Hydrological Program of Unesco.During the conference, the 3rd General Meeting of the European Network of Experimental and Representative Basins was held. This network of basins, covering nine countries in Europe, organizes periodic meetings and tries to enhance the compatibility of observations and methods of analysis, and to implement research projects of common interest.

  15. Reorientation of icy satellites by impact basins

    NASA Astrophysics Data System (ADS)

    Nimmo, F.; Matsuyama, I.

    2007-10-01

    Large impact basins are present on many of the icy satellites of the outer solar system. Assuming that their present-day topography is uncompensated, such basins can cause significant poleward reorientations for slow-rotating satellites. This reorientation may have been accompanied by transient large-amplitude wobble. The largest basins on Tethys, Rhea and Titania are predicted to have caused reorientations of roughly 4°, 7° and 12°, respectively, resulting in global tectonic stresses up to ~0.5 MPa. The potential anomalies associated with the basins can be up to one-third of those expected for a hydrostatic, tidally- and rotationally-deformed body, and may complicate interpretation of the satellite interior structure. Pluto and Charon, because of their slow rotation, are also likely to have undergone reorientation of 10-20° if they possess impact basins of comparable sizes to those of the Saturnian satellites.

  16. Petroleum geochemistry of the Zala Basin, Hungary

    USGS Publications Warehouse

    Clayton, J.L.; Koncz, I.

    1994-01-01

    The Zala basin is a subbasin within the Pannonian basin. Geochemical study of oils and rocks in the basin indicate that two, and possibly three, genetic oil types are present in the basin. Miocene source rocks, previously believed to be the predominant source rock, have expelled minor amounts of hydrocarbons. The main source rock is the Upper Triassic (Rhaetian) Kossen Marl Formation or its stratigraphic equivalent. Knowledge of the geochemical characteristics of oils derived from these Upper Triassic source rocks and understanding of the source rock distribution and maturation history are important for recognizing Triassic oil-source bed relationships and for further exploration in other basins in Hungary and other parts of Europe where Triassic source rocks are present. -from Authors

  17. Thermal state of the Arkoma Basin and the Anadarko Basin, Oklahoma

    NASA Astrophysics Data System (ADS)

    Lee, Youngmin

    1999-12-01

    One of the most fundamental physical processes that affects virtually all geologic phenomena in sedimentary basins is the flow of heat from the Earth's interiors. The Arkoma Basin and the Anadarko Basin, Oklahoma, are a prolific producer of both oil and natural gas. Both basins also have important geologic phenomena. Understanding the thermal state of the these basins is crucial to understanding the timing and extent of hydrocarbon generation, the genesis of Mississippi Valley-type ore deposits, and the origin of overpressures in the Anadarko Basin. In chapter one, heat flow and heat production in the Arkoma basin and Oklahoma Platform are discussed. Results of this study are not generally supportive of theories which invoke topographically driven regional groundwater flow from the Arkoma Basin in Late Pennsylvanian-Early Permian time (˜290 Ma) to explain the genesis of geologic phenomena. In chapter 2, different types of thermal conductivity temperature corrections that are commonly applied in terrestrial heat flow studies are evaluated. The invariance of the relative rankings with respect to rock porosity suggests the rankings may be valid with respect to in situ conditions. Chapter three addresses heat flow and thermal history of the Anadarko Basin and the western Oklahoma Platform. We found no evidence for heat flow to increase significantly from the Anadarko Basin in the south to the Oklahoma Platform to the north. In chapter four, overpressures in the Anadarko Basin, southwestern Oklahoma are discussed. Using scale analyses and a simple numerical model, we evaluated two endmember hypotheses (compaction disequilibrium and hydrocarbon generation) as possible causes of overpressuring. Geopressure models which invoke compaction disequilibrium do not appear to apply to the Anadarko Basin. The Anadarko Basin belongs to a group of cratonic basins which are tectonically quiescent and are characterized by the association of abnormal pressures with natural gas

  18. Determination of the Relationship between Hydrologic Processes and Basin Morphometry - The Lamos Basin (Mersin, Turkey)

    NASA Astrophysics Data System (ADS)

    Yıldırım, Ümit; Güler, Cüneyt

    2016-04-01

    This study has been carried out to determine the relationship between hydrologic processes and basin morphometry in the Lamos Basin, which is located at the northern part of the Mersin (SE Turkey). The morphometric parameters of the basin was derived from the 1:25K scale topographic map sheets that were digitized using ArcGIS 9.3.1 geographic information system (GIS) software. Morphometric parameters considered in this study include basin area, basin length, basin perimeter length, stream order, stream number, stream length, mean stream length, basin relief, drainage density, stream frequency, drainage texture, bifurcation ratio, form factor, elongation ratio, overland flow length, relief ratio, and hypsometric integral. The results have shown that there are 1252 individual stream reaches with a total length of 1414.1 km in the Lamos basin, which covers an area of 1358 km2 and has a length of 103 km in the N-S direction. Furthermore, the basin has a medium drainage density of 1.04 1/km with a stream frequency and drainage texture values of 0.92 and 4.33, respectively. The basin can be classified as elongated because of the low values of elongation ratio (0.48) and form factor (0.12). The hypsometric integral of the basin (0.58) indicates that it is in the youth period and thus reasonably sensitive to erosion. The values of drainage texture, drainage density, and stream frequency indicate that the Lamos basin is moderately well drained, therefore overland flow in the basin is not expected to be so quick. Thus, in case of occurrence of sudden peak flows, sensitivity to the land sliding and erosion may increase further. As a result, it is suggested that human activities in the basin should be limited in areas in fairly close proximity to the present day stream network to prevent or reduce the risk to life and property.

  19. Nucleoside-2',3'/3',5'-bis(thio)phosphate antioxidants are also capable of disassembly of amyloid beta42-Zn(ii)/Cu(ii) aggregates via Zn(ii)/Cu(ii)-chelation.

    PubMed

    Hevroni, Bosmat Levi; Major, Dan Thomas; Dixit, Mudit; Mhashal, Anil Ranu; Das, Susanta; Fischer, Bilha

    2016-05-18

    Currently, there is an urgent need for biocompatible metal-ion chelators capable of antioxidant activity and disassembly of amyloid beta (Aβ)-aggregates as potential therapeutics for Alzheimer's disease (AD). We recently demonstrated the promising antioxidant activity of adenine/guanine 2',3' or 3',5'-bis(thio)phosphate analogues, 2'-dA/G3'5'PO/S and A2'3'PO/S, and their affinity to Zn(ii)-ions. These findings encouraged us to evaluate them as agents for the dissolution of Aβ42-Zn(ii)/Cu(ii) aggregates. Specifically, we explored their ability to bind Cu(ii)/Zn(ii)-ions, the geometry and stoichiometry of these complexes, Cu(ii)/Zn(ii)-binding-sites and binding mode, and the ability of these analogues to dissolve Aβ42-Zn(ii)/Cu(ii) aggregates, as well as their effect on the secondary structure of those aggregates. Finally, we identified the most promising agents for dissolution of Aβ42-Zn(ii)/Cu(ii) aggregates. Specifically, we observed the formation of a 1 : 1 complex between 2'-dG3'5'PO and Cu(ii), involving O4 ligands. Zn(ii) was coordinated by both thiophosphate groups of 2'-dA3'5'PS and A2'3'PS involving O2S2 ligands in a 1 : 1 stoichiometry. A2'3'PS dissolves Aβ42-Zn(ii) and Aβ42-Cu(ii) aggregates as effectively as, and 2.5-fold more effectively than EDTA, respectively. Furthermore, 2'-dG3'5'PS and A2'3'PS reverted the Aβ42-M(ii) structure, back to that of the free Aβ42. Finally, cryo-TEM and TEM images confirmed the disassembly of Aβ42 and Aβ42-M(ii) aggregates by A2'3'PS. Hence, 2'-dG3'5'PS and A2'3'PS may serve as promising scaffolds for new AD therapeutics, acting as both effective antioxidants and agents for solubilization of Aβ42-Cu(ii)/Zn(ii) aggregates.

  20. Plio-Pleistocene drainage development in an inverted sedimentary basin: Vera basin, Betic Cordillera, SE Spain

    NASA Astrophysics Data System (ADS)

    Stokes, Martin

    2008-08-01

    The Vera basin is one of a series of interconnected Neogene-Quaternary sedimentary basins located within the Internal Zone of the Betic Cordillera (southeast Spain). Since the Pliocene the Vera basin has been subjected to low uplift rates (11-21 m Ma - 1 ) and inverted via compressive tectonics that are related to the ongoing oblique collision between the African and Iberian plates. Within this paper the sedimentary and geomorphic response to basin inversion is explored. Sedimentary processes and environments are established for key stratigraphic units of the Pliocene/Plio-Pleistocene basin fill and Pleistocene dissectional landscape. These data are subsequently utilised to reconstruct an evolving basin palaeogeography. Fault and uplift data are employed to discuss the role of tectonically driven basin inversion for controlling the resultant palaeogeographic changes and associated patterns of drainage development. During the Early-Mid Pliocene the Vera basin was characterised by shallow marine shelf conditions (Cuevas Formation). A major palaeogeographic reorganisation occurred during the Mid-Late Pliocene. Strike-slip movement along the eastern basin margin, coupled with uplift and basin emergence created a protected, partially enclosed marine embayment that was conducive for Gilbert-type fan-delta sedimentation from fluvial inputs along the northern and eastern basin margins (Espíritu Santo Formation). The Vera basin then became fully continental and internally drained through the development of a consequent drainage network that formed following the withdrawal of marine conditions during the Late Pliocene to Early Pleistocene. Alluvial fans developed along the northern and western basin margins, grading to a bajada and terminating in a playa lake in central basin areas (Salmerón Formation). During the Early-Mid Pleistocene a switch from basin infilling to dissection took place, recorded by alluvial fan incision, a switch to braided river sedimentation and

  1. Lunar Multiring Basins and the Cratering Process

    NASA Astrophysics Data System (ADS)

    Wieczorek, Mark A.; Phillips, Roger J.

    1999-06-01

    Numerous studies of the lunar gravity field have concluded that the lunar Moho is substantially uplifted beneath the young multiring basins. This uplift is presumably due to the excavation of large quantities of crustal material during the cratering process and subsequent rebound of the impact basin floor. Using a new dual-layered crustal thickness model of the Moon, the excavation cavities of some nearside multiring basins (Grimaldi and larger, and younger than Tranquillitatis) were reconstructed by restoring the uplifted Moho to its preimpact location. The farside South Pole-Aitken (SPA) basin was also considered due to its importance in deciphering lunar evolution. Restoring the Moho to its preimpact position beneath these basins resulted in a roughly parabolic depression from which the depth and diameter of the excavation cavity could be determined. Using these reconstructed excavation cavities, the basin-forming process was investigated. Excavation cavity diameters were generally found to be on the small side of most previous estimates (for Orientale the modeled excavation cavity lies within the Inner Rook Ring). Additionally, with the exception of the three largest basins (Serenitatis, Imbrium, and South Pole-Aitken) the depth/diameter ratios of the excavation cavities were found to be 0.115±0.005, a value consistent with theoretical and experimental results for impact craters orders of magnitude smaller in size. The three largest basins, however, appear to have significantly shallower depths of excavation compared to this trend. It is possible that this may reflect a different physical process of crater formation (e.g., nonproportional scaling), special impact conditions, or postimpact modification processes. The crustal thickness model also shows that each basin is surrounded by an annulus of thickened crust. We interpret this thickened crust as representing thick basin ejecta deposits, and we show that the radial variation in the thickness of these

  2. Rocky Mountain Tertiary coal-basin models and their applicability to some world basins

    USGS Publications Warehouse

    Flores, R.M.

    1989-01-01

    Tertiary intermontane basins in the Rocky Mountain region of the United States contain large amounts of coal resources. The first major type of Tertiary coal basin is closed and lake-dominated, either mud-rich (e.g., North Park Basin, Colorado) or mud plus carbonate (e.g., Medicine Lodge Basin, Montana), which are both infilled by deltas. The second major type of Tertiary coal basin is open and characterized by a preponderance of sediments that were deposited by flow-through fluvial systems (e.g., Raton Basin, Colorado and New Mexico, and Powder River Basin, Wyoming and Montana). The setting for the formation of these coals varies with the type of basin sedimentation, paleotectonism, and paleoclimate. The mud-rich lake-dominated closed basin (transpressional paleotectonism and warm, humid paleoclimate), where infilled by sandy "Gilbert-type" deltas, contains thick coals (low ash and low sulfur) formed in swamps of the prograding fluvial systems. The mud- and carbonate-rich lake-dominated closed basin is infilled by carbonate precipitates plus coarse-grained fan deltas and fine-grained deltas. Here, thin coals (high ash and high sulfur) formed in swamps of the fine-grained deltas. The coarse-clastic, open basins (compressional paleotectonism and warm, paratropical paleoclimate) associated with flow-through fluvial systems contain moderately to anomalously thick coals (high to low ash and low sulfur) formed in swamps developed in intermittently abandoned portions of the fluvial systems. These coal development patterns from the Tertiary Rocky Mountain basins, although occurring in completely different paleotectonic settings, are similar to that found in the Tertiary, Cretaceous, and Permian intermontane coal basins in China, New Zealand, and India. ?? 1989.

  3. Wyoming Basin Rapid Ecoregional Assessment

    USGS Publications Warehouse

    Carr, Natasha B.; Melcher, Cynthia P.

    2015-08-28

    We evaluated Management Questions (Core and Integrated) for each species and community for the Wyoming Basin REA. Core Management Questions address primary management issues, including (1) where is the Conservation Element, and what are its key ecological attributes (characteristics of species and communities that may affect their long-term persistence or viability); (2) what and where are the Change Agents; and (3) how do the Change Agents affect the key ecological attributes? Integrated Management Questions synthesize the Core Management Questions as follows: (1) where are the areas with high landscape-level ecological values; (2) where are the areas with high landscape-level risks; and (3) where are the potential areas for conservation, restoration, and development? The associated maps and key findings for each Management Question are summarized for each Conservation Element in individual chapters. Additional chapters on landscape intactness and an REA synthesis are included.

  4. Delaware Basin Monitoring Annual Report

    SciTech Connect

    Washington Regulatory and Environmental Services; Washington TRU Solutions LLC

    2003-09-30

    The Delaware Basin Drilling Surveillance Program (DBDSP) is designed to monitor drilling activities in the vicinity of the Waste Isolation Pilot Plant (WIPP). This program is based on Environmental Protection Agency (EPA) requirements. The EPA environmental standards for the management and disposal of transuranic (TRU) radioactive waste are codified in 40 CFR Part 191 (EPA 1993). Subparts B and C of the standard address the disposal of radioactive waste. The standard requires the Department of Energy (DOE) to demonstrate the expected performance of the disposal system using a probabilistic risk assessment or performance assessment (PA). This PA must show that the expected repository performance will not release radioactive material above limits set by the EPA's standard. This assessment must include the consideration of inadvertent drilling into the repository at some future time.

  5. Delaware Basin Monitoring Annual Report

    SciTech Connect

    Washington Regulatory and Environmental Services; Washington TRU Solutions LLC

    2004-09-30

    The Delaware Basin Drilling Surveillance Program (DBDSP) is designed to monitor drilling activities in the vicinity of the Waste Isolation Pilot Plant (WIPP). This program is based on Environmental Protection Agency (EPA) requirements. The EPA environmental standards for the management and disposal of transuranic (TRU) radioactive waste are codified in 40 CFR Part 191 (EPA 1993). Subparts B and C of the standard address the disposal of radioactive waste. The standard requires the Department of Energy (DOE) to demonstrate the expected performance of the disposal system using a probabilistic risk assessment or performance assessment (PA). This PA must show that the expected repository performance will not release radioactive material above limits set by the EPA's standard. This assessment must include the consideration of inadvertent drilling into the repository at some future time.

  6. Delaware Basin Monitoring Annual Report

    SciTech Connect

    Washington Regulatory and Environmental Services; Washington TRU Solutions LLC

    2005-09-30

    The Delaware Basin Drilling Surveillance Program (DBDSP) is designed to monitor drilling activities in the vicinity of the Waste Isolation Pilot Plant (WIPP). This program is based on Environmental Protection Agency (EPA) requirements. The EPA environmental standards for the management and disposal of transuranic (TRU) radioactive waste are codified in 40 CFR Part 191 (EPA 1993). Subparts B and C of the standard address the disposal of radioactive waste. The standard requires the Department of Energy (DOE) to demonstrate the expected performance of the disposal system using a probabilistic risk assessment or performance assessment (PA). This PA must show that the expected repository performance will not release radioactive material above limits set by the EPA's standard. This assessment must include the consideration of inadvertent drilling into the repository at some future time.

  7. Delaware Basin Monitoring Annual Report

    SciTech Connect

    Washington Regulatory and Environmental Services; Washington TRU Solutions LLC

    2000-09-28

    The Delaware Basin Drilling Surveillance Program (DBDSP) is designed to monitor drilling activities in the vicinity of the Waste Isolation Pilot Plant (WIPP). This program is based on Environmental Protection Agency (EPA) requirements. The EPA environmental standards for the management and disposal of transuranic (TRU) radioactive waste are codified in 40 CFR Part 191 (EPA 1993). Subparts B and C of the standard address the disposal of radioactive waste. The standard requires the Department of Energy (DOE) to demonstrate the expected performance of the disposal system using a probabilistic risk assessment or performance assessment (PA). This PA must show that the expected repository performance will not release radioactive material above limits set by the EPA's standard. This assessment must include the consideration of inadvertent drilling into the repository at some future time.

  8. Umatilla Basin Habitat Improvement Project.

    SciTech Connect

    Bailey, Timothy D.

    1990-01-01

    This annual report is in fulfillment of contract obligations with Bonneville Power Administration which is the funding source for the Oregon Department of Fish and Wildlife's Umatilla Basin Habitat Improvement Project. The major activities undertaken during this report period were: procurement of 17 cooperative lease agreements with private landowners, design and layout of 8.6 miles of riparian exclosure fence and 3.0 miles of instream structures, development of five fencing contracts and six instream work contracts. Results include implementation of 10 miles of fencing and 3 miles of instream work. Other activities undertaken during this report period are: data collection from 90 habitat monitoring transects, collection and summarization of temperature data, photopoint establishment, coordination with numerous agencies and tribes and education of all age groups on habitat improvement and protection. 4 refs., 4 figs., 6 tabs.

  9. Petroleum potential of the Reggane Basin, Algeria

    SciTech Connect

    Boudjema, A.; Hamel, M.; Mohamedi, A.; Lounissi, R. )

    1990-05-01

    The intracratonic Reggane basin is located on the Saharan platform, southwest of Algeria. The basin covers an area of approximately 140,000 km{sup 2}, extending between the Eglab shield in the south and the Ougarta ranges in the north. Although exploration started in the early 1950s, only a few wells were drilled in this basin. Gas was discovered with a number of oil shows. The sedimentary fill, mainly Paleozoic shales and sandstones, has a thickness exceeding 5,000 m in the central part of the basin. The reservoirs are Cambrian-Ordovician, Siegenian, Emsian, Tournaisian, and Visean sandstones with prospective petrophysical characteristics. Silurian Upper Devonian and, to a lesser extent Carboniferous shales are the main source rocks. An integrated study was done to assess the hydrocarbon potential of this basin. Tectonic evolution source rocks and reservoirs distribution maturation analyses followed by kinetic modeling, and hydrogeological conditions were studied. Results indicate that gas accumulations could be expected in the central and deeper part of the basin, and oil reservoirs could be discovered on the basin edge.

  10. Submarine Landslides in Arctic Sedimentation: Canada Basin

    USGS Publications Warehouse

    Mosher, David C.; Shimeld, John; Hutchinson, Deborah R.; Lebedova-Ivanova, N; Chapman, C.

    2016-01-01

    Canada Basin of the Arctic Ocean is the least studied ocean basin in the World. Marine seismic field programs were conducted over the past 6 years using Canadian and American icebreakers. These expeditions acquired more than 14,000 line-km of multibeam bathymetric and multi-channel seismic reflection data over abyssal plain, continental rise and slope regions of Canada Basin; areas where little or no seismic reflection data existed previously. Canada Basin is a turbidite-filled basin with flat-lying reflections correlateable over 100s of km. For the upper half of the sedimentary succession, evidence of sedimentary processes other than turbidity current deposition is rare. The Canadian Archipelago and Beaufort Sea margins host stacked mass transport deposits from which many of these turbidites appear to derive. The stratigraphic succession of the MacKenzie River fan is dominated by mass transport deposits; one such complex is in excess of 132,000 km2 in area and underlies much of the southern abyssal plain. The modern seafloor is also scarred with escarpments and mass failure deposits; evidence that submarine landsliding is an ongoing process. In its latest phase of development, Canada Basin is geomorphologically confined with stable oceanographic structure, resulting in restricted depositional/reworking processes. The sedimentary record, therefore, underscores the significance of mass-transport processes in providing sediments to oceanic abyssal plains as few other basins are able to do.

  11. Metabolic principles of river basin organization.

    PubMed

    Rodriguez-Iturbe, Ignacio; Caylor, Kelly K; Rinaldo, Andrea

    2011-07-19

    The metabolism of a river basin is defined as the set of processes through which the basin maintains its structure and responds to its environment. Green (or biotic) metabolism is measured via transpiration and blue (or abiotic) metabolism through runoff. A principle of equal metabolic rate per unit area throughout the basin structure is developed and tested in a river basin characterized by large heterogeneities in precipitation, vegetation, soil, and geomorphology. This principle is suggested to have profound implications for the spatial organization of river basin hydrologic dynamics, including the minimization of energy expenditure known to control the scale-invariant characteristics of river networks over several orders of magnitude. Empirically derived, remarkably constant rates of average transpiration per unit area through the basin structure lead to a power law for the probability distribution of transpiration from a randomly chosen subbasin. The average runoff per unit area, evaluated for subbasins of a wide range of topological magnitudes, is also shown to be remarkably constant independently of size. A similar result is found for the rainfall after accounting for canopy interception. Allometric scaling of metabolic rates with size, variously addressed in the biological literature and network theory under the label of Kleiber's law, is similarly derived. The empirical evidence suggests that river basin metabolic activity is linked with the spatial organization that takes place around the drainage network and therefore with the mechanisms responsible for the fractal geometry of the network, suggesting a new coevolutionary framework for biological, geomorphological, and hydrologic dynamics.

  12. Gladden Pull-Apart Basin, offshore Belize

    SciTech Connect

    Morrice, S. )

    1993-02-01

    The junction of the American and Caribbean plates in Belize has created a complex structural setting for oil and gas exploration. Recent seismic offshore Belize has been used to identify three structural provinces, from west to east: a shallow thrust zone, a narrow upthrown wrench faulted zone and a deeper extensional basin, named the Gladden Pull-Apart Basin. Hydrocarbon leakage from recent fault movement appears to have depleted the shallow structures to the west, but the pull-apart basin has a thick sequence of low-frequency clay-dominated sealing rocks with the potential to preserve hydrocarbon accumulations in Cretaceous carbonate banks. These buried carbonate are of the same age and depositional environment of Mexico's Golden Lane/Tabasco Reforma carbonate banks which are world class giant fields. The Belize and Mexican carbonate banks are within the same Cretaceous depositional basin, the Peten Basin. Seismic interpretations in offshore Belize have been integrated with gravity and magnetic surveys. This provides additional support for the deep extensional basin. The location of the thick Cretaceous carbonate banks is better interpreted with the integration of these three geophysical tools. Airborne geochemical surveys were used to detect the presence of oil seeps on the east and west basin margins.

  13. Report card--Murray-Darling Basin--2001.

    PubMed

    Goss, K

    2002-01-01

    Ongoing deterioration of the riverine environments of the Murray-Darling Basin led the Murray-Darling Basin Ministerial Council to introduce a Cap in 1995 to halt the growth in diversions of water for consumptive use. This initiative recognised the finite nature of water resources in the Basin and sought to introduce a balance between off-stream use of water and protection of the riverine environment. But the cap is only one step, albeit a fundamental one, in restoring the Basin's rivers--it is a "stake in the ground". Parties to the Murray-Darling Basin Initiative recognise the need to reverse decades of creeping decline if the Basin's rivers and riverine environments are to return to a more ecologically sustainable condition. In the last 12 months, Council and Commission have taken far-reaching decisions designed to restore the Basin's Rivers. Many of these decisions, even 10 years ago, would have been unimaginable. The Report Card will explain the need for a number of recent decisions that will impact on the future of the Basin's rivers. For example, Council's decision to establish an Environmental Manager function in the Office of the Commission was made in the context of the recently agreed Integrated Catchment Management (ICM) Policy, and supporting Sustainable Rivers Audit. The role of targets and accountabilities under the ICM Policy will also be discussed. The Report Card will also present a snapshot of the state of the Basin's rivers and the actions being taken at a range of scales and locations in response to identified problems. Because some of the key initiatives are still in development, this Report Card will set the scene by describing where our attention is being focused and why.

  14. Thermal conditions in the Anadarko basin, Oklahoma

    SciTech Connect

    Kelley, S.A.; Gallardo, J.D.; Carter, L.C.; Blackwell, D.D. )

    1991-03-01

    Heat flow, bottom-hole temperature (BHT), and thermal conductivity data are used to evaluate the present thermal conditions in the Anadarko basin. Heat flow values decrease from 54-62 mWm{sup {minus}2} in the northern part of the basin to 39-53 mWm{sup {minus}2} in the southern portion of the basin. The variation in the regional conductive heat flow is controlled by basin geometry and by the distribution of radiogenic elements in the basement. The heat flow, thermal conductivity, and lithologic information were combined to construct a 3-D model of the temperature structure of the Anadarko basin. The highest temperatures sedimentary rocks older than Pennsylvanian are offset 35 km north-northwest of the deepest part of the basin. This offset is related to the regional increase in heat flow to the north and to the presence of high thermal conductivity granite wash adjacent to the Wichita Mountains. A plot of the temperature difference between the equilibrium temperatures estimated from the model and the measured BHTs as a function of depth is remarkably similar to the published correction curve for BHTs for wells in Oklahoma. Vitrinite reflectance and apatite fission-track (FT) data are used to estimate the paleogeothermal conditions in the basin. Published vitrinite reflectance values are consistent with a past geographic temperature distribution comparable to the observed distribution with the maximum values offset from the basin axis. FT analysis of sandstones from wells in the southeastern portion of the basin indicates that subsurface temperatures were at least 30C higher than at present, suggest the possibility of substantial erosion in this area.

  15. Flexural Origin of the Puget Basins: Implications for the Seattle Fault and Puget Basin Tectonics

    NASA Astrophysics Data System (ADS)

    Crosson, R. S.; Symons, N. P.

    2001-12-01

    At least five distinct basins of varying depth, including the Seattle basin, form a semi-circular ring around the eastern Olympic Mts. Although the Seattle basin has been postulated to result from a northward vergent thrust on the Seattle fault, other basins have a less clear relationship to faulting. A purely thrust origin for the Seattle basin requires uplift, which is not observed, south of the Seattle fault to isostatically balance the large mass deficiency of the Seattle basin. High-resolution P-wave velocity imaging of the Puget region using earthquakes, data from the recent SHIPS experiments, and data from earlier explosion experiments shows that the Puget basins are underlain by approximately 15 km of "tectonically" strong Crescent formation (part of the Coast Range Terrain - CRT). Low velocity core rocks of the eastern Olympics are emplaced beneath the CRT in a radial pattern that mirrors the pattern of the Puget basins, strongly suggesting that the basins are genetically related to the Olympic structure. A model of basin formation that is consistent with gravity and seismic data, and that explains the observed radial pattern is elastic flexural down-warp in response to uplift and subsequent erosion of the CRT in the central Olympic Mts. The CRT is now erosionally removed from the Olympic core, exposing the underlying accretionary wedge complex. The available information on timing of the Olympic uplift generally agrees with the inferred timing of basin subsidence. Since the "lever arm" which forced the basins downward is removed by erosion from the eastern Olympics, basin subsidence has probably stopped, and isostatic rebound of the Seattle and other basins should play a role in current tectonics. Relative uplift of the Seattle basin, consistent with isostatic rebound, explains the north-side-up mechanism of the June 1997 M 4.9 earthquake near Bremerton, the north-side-up pattern of faults trenched on southern Bainbridge Island, and possibly the uplift of

  16. Tectono-stratigraphic evolution of an inverted extensional basin: the Cameros Basin (north of Spain)

    NASA Astrophysics Data System (ADS)

    Omodeo Salè, Silvia; Guimerà, Joan; Mas, Ramón; Arribas, José

    2014-09-01

    The Cameros Basin is a part of the Mesozoic Iberian Rift. It is an extensional basin formed during the late Jurassic and early Cretaceous, in the Mesozoic Iberian Rift context, and it was inverted in the Cenozoic as a result of the Alpine contraction. This work aims to reconstruct the tectono-stratigraphic evolution of the basin during the Mesozoic, using new and revised field, geophysical and subsurface data. The construction of a basin-wide balanced section with partial restorations herein offers new insights into the geometry of the syn-rift deposits. Field data, seismic lines and oil well data were used to identify the main structures of the basin and the basin-forming mechanisms. Mapping and cross-sectional data indicate the marked thickness variation of the depositional sequences across the basin, suggesting that the extension of the depositional area varied during the syn-rift stage and that the depocentres migrated towards the north. From field observation and seismic line interpretation, an onlap of the depositional sequences to the north, over the marine Jurassic substratum, can be deduced. In the last few decades, the structure and geometry of the basin have been strongly debated. The structure and geometry of the basin infill reconstructed herein strongly support the interpretation of the Cameros Basin as an extensional-ramp synclinal basin formed on a blind south-dipping extensional ramp. The gradual hanging-wall displacement to the south shifted the depocentres to the north over time, thus increasing the basin in size northwards, with onlap geometry on the pre-rift substratum. The basin was inverted by means of a main thrust located in a detachment located in the Upper Triassic beds (Keuper), which branched in depth with the Mesozoic extensional fault flat. The reconstruction of the tectono-stratigraphic evolution of the Cameros Basin proposed herein represents a synthesis and an integration of previous studies of the structure and geometry of the

  17. YARD NO. 3 BASINS (GRAVING DOCKS), VIEW TO EASTNORTHEAST AT ...

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

    YARD NO. 3 BASINS (GRAVING DOCKS), VIEW TO EAST-NORTHEAST AT THE SOUTH END OF THE CRANEWAY AND GALLERY BETWEEN BASINS NO. 1 AND 2, LOOKING ACROSS SOUTH END OF BASIN NO. 1 (THE WESTERN-MOST BASIN) - Rosie the Riveter National Historical Park, Graving Docks, Shipyard No. 3, Richmond, Contra Costa County, CA

  18. Stratigraphy of the Caloris basin, Mercury

    USGS Publications Warehouse

    McCauley, J.F.; Guest, J.E.; Schaber, G.G.; Trask, N.J.; Greeley, R.

    1981-01-01

    The 1300-km-diameter Caloris impact basin is surrounded by well-defined ejecta units that can be recognized from more than 1000 km, radially outward from the basin edge. A formal rock stratigraphic nomenclature is proposed for the Caloris ejecta units, which are collectively called the Caloris Group. Each of the individual formations within the Group are described and compared to similar rock units associated with the lunar Imbrium and Orientale basins. A crater degradation chronology, linked the the Caloris event, is also proposed to assist in stratigraphic correlation on a Mercury-wide basis. ?? 1981.

  19. K Basins isolation barriers summary report

    SciTech Connect

    Strickland, G.C., Westinghouse Hanford

    1996-07-31

    The 105-K East and 105-K West fuel storage basins (105-K Basins) were designed and constructed in the early 1950`s for interim storage of irradiated fuel following its discharge from the reactors. The 105-K- East and 105-K West reactor buildings were constructed first, and the associated storage basins were added about a year later. The construction joint between each reactor building structure and the basin structure included a flexible membrane waterstop to prevent leakage. Water in the storage basins provided both radiation shielding and cooling to remove decay heat from stored fuel until its transfer to the Plutonium Uranium Extraction (PUREX) Facility for chemical processing. The 105-K West Reactor was permanently shut down in February 1970; the 105-K East Reactor was permanently shut down in February 1971. Except for a few loose pieces, fuel stored in the basins at that time was shipped to the PUREX Facility for processing. The basins were then left idle but were kept filled with water. The PUREX Facility was shut down and placed on wet standby in 1972 while N Reactor continued to operate. When the N Reactor fuel storage basin began to approach storage capacity, the decision was made to modify the fuel storage basins at 105-K East and 105-K West to provide additional storage capacity. Both basins were subsequently modified (105-K East in 1975 and 105-K West in 1981) to provide for the interim handling and storage of irradiated N Reactor fuel. The PUREX Facility was restarted in November 1983 to provide 1698 additional weapons-grade plutonium for the United States defense mission. The facility was shut down and deactivated in December 1992 when the U.S. Department of Energy (DOE) determined that the plant was no longer needed to support weapons-grade plutonium production. When the PUREX Facility was shut down, approximately 2.1 x 1 06 kg (2,100 metric tons) of irradiated fuel aged 7 to 23 years was left in storage in the 105-K Basins pending a decision on

  20. Discharge forecasts in mountain basins based on satellite snow cover mapping. [Dinwoody Creek Basin, Wyoming and the Dischma Basin, Switzerland

    NASA Technical Reports Server (NTRS)

    Martinec, J.; Rango, A. (Principal Investigator)

    1980-01-01

    The author has identified the following significant results. A snow runoff model developed for European mountain basins was used with LANDSAT imagery and air temperature data to simulate runoff in the Rocky Mountains under conditions of large elevation range and moderate cloud cover (cloud cover of 40% or less during LANDSAT passes 70% of the time during a snowmelt season). Favorable results were obtained for basins with area not exceeding serval hundred square kilometers and with a significant component of subsurface runoff.

  1. BASIN STRUCTURE FROM TWO-DIMENSIONAL SEISMIC REFLECTION DATA, CRAZY MOUNTAINS BASIN, MONTANA

    SciTech Connect

    David J. Taylor

    2003-08-01

    Some 140 miles of multichannel seismic reflection data, acquired commercially in the 1970's, were reprocessed by the U.S. Geological Survey in late 2000 and early 2001 to interpret the subsurface geology of the Crazy Mountains Basin, an asymmetric Laramide foreland basin located in south-central Montana. The seismic data indicate that the northwestern basin margin is controlled by a thrust fault that places basement rocks over a thick (22,000 feet) sequence of Paleozoic and Mesozoic sedimentary rocks to the south. From the deep basin trough, Paleozoic through Tertiary rocks slope gently upward to the south and southeast. The northern boundary of the basin, which is not imaged well by the seismic data, appears to be folded over a basement ridge rather than being truncated against a fault plane. Seismic data along the basin margin to the south indicate that several fault controlled basement highs may have been created by thin-skinned tectonics where a series of shallow thrust faults cut Precambrian, Paleozoic, and early Mesozoic rocks, whereas, in contrast, Cretaceous and Tertiary strata are folded. The data are further interpreted to indicate that this fault-bounded asymmetric basin contains several structures that possibly could trap hydrocarbons, provided source rocks, reservoirs, and seals are present. In addition, faults in the deep basin trough may have created enough fracturing to enhance porosity, thus developing ''sweet spots'' for hydrocarbons in basin-centered continuous gas accumulations.

  2. Superposition of tectonic structures leading elongated intramontane basin: the Alhabia basin (Internal Zones, Betic Cordillera)

    NASA Astrophysics Data System (ADS)

    Martínez-Martos, Manuel; Galindo-Zaldivar, Jesús; Martínez-Moreno, Francisco José; Calvo-Rayo, Raquel; Sanz de Galdeano, Carlos

    2017-01-01

    The relief of the Betic Cordillera was formed since the late Serravallian inducing the development of intramontane basins. The Alhabia basin, situated in the central part of the Internal Zones, is located at the intersection of the Alpujarran Corridor, the Tabernas basin, both trending E-W, and the NW-SE oriented Gádor-Almería basin. The geometry of the basin has been constrained by new gravity data. The basin is limited to the North by the Sierra de Filabres and Sierra Nevada antiforms that started to develop in Serravallian times under N-S shortening and to the south by Sierra Alhamilla and Sierra de Gádor antiforms. Plate convergence in the region rotated counter-clockwise in Tortonian times favouring the formation of E-W dextral faults. In this setting, NE-SW extension, orthogonal to the shortening direction, was accommodated by normal faults on the SW edge of Sierra Alhamilla. The Alhabia basin shows a cross-shaped depocentre in the zone of synform and fault intersection. This field example serves to constrain recent counter-clockwise stress rotation during the latest stages of Neogene-Quaternary basin evolution in the Betic Cordillera Internal Zones and underlines the importance of studying the basins' deep structure and its relation with the tectonic structures interactions.

  3. Death of a carbonate basin: The Niagara-Salina transition in the Michigan basin

    SciTech Connect

    Leibold, A.W.; Howell, P.D. )

    1991-03-01

    The A-O Carbonate in the Michigan basin comprises a sequence of laminated calcite/anhydrite layers intercalated with bedded halite at the transition between normal marine Niagaran carbonates and lower Salina Group evaporites. The carbonate/anhydrite interbeds represent freshing events during initial evaporative concentration of the Michigan basin. Recent drilling in the Michigan basin delineates two distinct regions of A-O Carbonate development: a 5 to 10 m thick sequence of six 'laminites' found throughout most of the western and northern basin and a 10 to 25 m thick sequence in the southeastern basin containing both thicker 'laminates' and thicker salt interbeds. Additionally, potash deposits of the overlying A-1 evaporite unit are restricted to the northern and western basin regions. The distribution of evaporite facies in these two regions is adequately explained by a source of basin recharge in the southeast-perhaps the 'Clinton Inlet' of earlier workers. This situation suggest either that: (1) the source of basin recharge is alternately supplying preconcentrated brine and more normal marine water, or (2) that the basin received at least two distinct sources of water during A-O deposition.

  4. VIEW TO EAST OF THE NORTH END OF BASIN NO. ...

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

    VIEW TO EAST OF THE NORTH END OF BASIN NO. 1 (THE WESTERN-MOST BASIN) SHOWING THE CRANEWAY AND GALLERY BETWEEN BASINS NO. 1 AND 2. BASSWOOD BUOY TENDER AND THREE SMALL VESSELS ARE BERTHED IN BASIN NO. 1. LARGER VESSELS ARE BERTHED IN BASINS TO THE EAST, SEEN IN BACKGROUND - Rosie the Riveter National Historical Park, Graving Docks, Shipyard No. 3, Richmond, Contra Costa County, CA

  5. Hydro Impact Basin Ribbon-Cutting Ceremony

    NASA Video Gallery

    August 9, 2011 -- Ribbon-cutting ceremony for the Hydro Impact Basin at NASA's Langley Research Center in Hampton, Va. The HIB expands NASA's capability to test and certify future spacecraft for wa...

  6. Program Updates - San Antonio River Basin

    EPA Pesticide Factsheets

    This page will house updates for this urban waters partnership location. As projects progress, status updates can be posted here to reflect the ongoing work by partners in San Antonio working on the San Antonio River Basin.

  7. Petroleum potential of the Libyan sedimentary basins

    SciTech Connect

    Hammuda, O.S.; Sbeta, A.M.

    1988-08-01

    Contrary to prevailing opinion, all Libyan sedimentary basins and the Al-Jabal Al-Akhdar platform contain prolific petroleum accumulations with very high prospectivity. A systematic review of the types of traps and pays in this central part of the southern Mediterranean province reveals great variability in reservoir and source rock characteristics. The reservoir rocks are of almost all geologic ages. The thick source rock sequences also vary in nature and organic content. The organic-rich facies have accumulated in intracratonic and passive margin basins or in marginal seas. Most of the oil discovered thus far in these basins is found in large structural traps. Future discoveries of stratigraphic traps or small structural traps will require intensified efforts and detailed studies using up-to-date multidisciplinary techniques in sedimentary tectonics, biostratigraphic facies analysis, and geochemical prospecting in order to develop a better understanding of these basins, thus improving their prospectivity.

  8. Fishes of the White River basin, Indiana

    USGS Publications Warehouse

    Crawford, Charles G.; Lydy, Michael J.; Frey, Jeffrey W.

    1996-01-01

    Since 1875, researchers have reported 158 species of fish belonging to 25 families in the White River Basin. Of these species, 6 have not been reported since 1900 and 10 have not been reported since 1943. Since the 1820's, fish communities in the White River Basin have been affected by the alteration of stream habitat, overfishing, the introduction of non-native species, agriculture, and urbanization. Erosion resulting from conversion of forest land to cropland in the 1800's led to siltation of streambeds and resulted in the loss of some silt-sensitive species. In the early 1900's, the water quality of the White River was seriously degraded for 100 miles by untreated sewage from the City of Indianapolis. During the last 25 years, water quality in the basin has improved because of efforts to control water pollution. Fish communities in the basin have responded favorably to the improved water quality.

  9. Tidal frequency estimation for closed basins

    NASA Technical Reports Server (NTRS)

    Eades, J. B., Jr.

    1978-01-01

    A method was developed for determining the fundamental tidal frequencies for closed basins of water, by means of an eigenvalue analysis. The mathematical model employed, was the Laplace tidal equations.

  10. Pacific Basin Communication Study, volume 2

    NASA Technical Reports Server (NTRS)

    Young, E. L.; Hurd, J. N.

    1981-01-01

    Users' meeting summary report, chronology of visits, economic data for forum countries, techniques used in the study, communication choices, existing resources in the Pacific Basin, and warc 79 region 3 rules and regulations were presented in volume 2.

  11. K-Basins S/RIDS

    SciTech Connect

    Watson, D.J.

    1997-08-01

    The Standards/Requirements Identification Document (S/RID) is a list of the Environmental, Safety, and Health (ES{ampersand}H) and Safeguards and Security (SAS) standards/requirements applicable to the K Basins facility.

  12. K-Basins S/RIDS

    SciTech Connect

    Watson, D.J.

    1995-09-22

    The Standards/Requirements Identification Document(S/RID) is a list of the Environmental, Safety, and Health (ES&H) and Safeguards and Security (SAS) standards/requirements applicable to the K Basins facility

  13. KE Basin water dispositioning engineering study

    SciTech Connect

    Hunacek, G.S.; Gahir, S.S.

    1994-09-23

    This engineering study is a feasibility study of KE Basin water treatment to an acceptable level and dispositioning the treated water to Columbia River, ground through ETF or to air through evaporation.

  14. River Basin Standards Interoperability Pilot

    NASA Astrophysics Data System (ADS)

    Pesquer, Lluís; Masó, Joan; Stasch, Christoph

    2016-04-01

    There is a lot of water information and tools in Europe to be applied in the river basin management but fragmentation and a lack of coordination between countries still exists. The European Commission and the member states have financed several research and innovation projects in support of the Water Framework Directive. Only a few of them are using the recently emerging hydrological standards, such as the OGC WaterML 2.0. WaterInnEU is a Horizon 2020 project focused on creating a marketplace to enhance the exploitation of EU funded ICT models, tools, protocols and policy briefs related to water and to establish suitable conditions for new market opportunities based on these offerings. One of WaterInnEU's main goals is to assess the level of standardization and interoperability of these outcomes as a mechanism to integrate ICT-based tools, incorporate open data platforms and generate a palette of interchangeable components that are able to use the water data emerging from the recently proposed open data sharing processes and data models stimulated by initiatives such as the INSPIRE directive. As part of the standardization and interoperability activities in the project, the authors are designing an experiment (RIBASE, the present work) to demonstrate how current ICT-based tools and water data can work in combination with geospatial web services in the Scheldt river basin. The main structure of this experiment, that is the core of the present work, is composed by the following steps: - Extraction of information from river gauges data in OGC WaterML 2.0 format using SOS services (preferably compliant to the OGC SOS 2.0 Hydrology Profile Best Practice). - Model floods using a WPS 2.0, WaterML 2.0 data and weather forecast models as input. - Evaluation of the applicability of Sensor Notification Services in water emergencies. - Open distribution of the input and output data as OGC web services WaterML, / WCS / WFS and with visualization utilities: WMS. The architecture

  15. Assessment of undiscovered carboniferous coal-bed gas resources of the Appalachian Basin and Black Warrior Basin Provinces, 2002

    SciTech Connect

    Milici, R.C.; Hatch, J.R.

    2004-09-15

    Coalbed methane (CBM) occurs in coal beds of Mississippian and Pennsylvanian (Carboniferous) age in the Appalachian basin, which extends almost continuously from New York to Alabama. In general, the basin includes three structural subbasins: the Dunkard basin in Pennsylvania, Ohio, and northern West Virginia; the Pocahontas basin in southern West Virginia, eastern Kentucky, and southwestern Virginia; and the Black Warrior basin in Alabama and Mississippi. For assessment purposes, the Appalachian basin was divided into two assessment provinces: the Appalachian Basin Province from New York to Alabama, and the Black Warrior Basin Province in Alabama and Mississippi. By far, most of the coalbed methane produced in the entire Appalachian basin has come from the Black Warrior Basin Province. 8 refs., 1 fig., 1 tab.

  16. Ordovician chitinozoan zones of Great Basin

    SciTech Connect

    Hutter, T.J.

    1987-08-01

    Within the Basin and Range province of the Great Basin of the western US, Ordovician chitinozoans have been recovered in two major lithic facies; the western eugeosynclinal facies and the eastern miogeosynclinal facies. Chitinozoans recovered from these facies range in age from Arenig to Ashgill. Extensive collections from this area make possible the establishment of chitinozoan faunal interval zones from the Ordovician of this area. Selected species of biostratigraphic value include, in chronostratigraphic order, Lagenochitina ovoidea Benoit and Taugourdeau, 1961, Conochitina langei Combaz and Peniguel, 1972, Conochitinia poumoti Combaz and Penique, Desmochitina cf. nodosa Eisenack, 1931, Conochitina maclartii Combaz and Peniguel, 1972, Conochitina robusta Eisenack, 1959, Angochitina capitallata Eisenack, 1937, Sphaerochitina lepta Jenkins. 1970, and Ancyrochitina merga Jenkins, 1970. In many cases, these zones can be divided into additional sub-zones using chitinozoans and acritarchs. In all cases, these chitinozoan faunal zones are contrasted with established American graptolite zones of the area, as well as correlated with British standard graptolite zones. The composition of these faunas of the western US Great Basin is similar to that of the Marathon region of west Texas and the Basin Ranges of Arizona and New Mexico, to which direct comparisons have been made. There also appears to be a great similarity with the microfaunas and microfloras of the Ordovician of the Canning basin of western Australia. The Ordovician chitinozoan faunal interval zones established for the Basin and Range province of the Great Basin of the western US also appear to be applicable to the Marathon region of west Texas and the Basin Ranges of Arizona and New Mexico.

  17. Paraguay river basin response to seasonal rainfall

    NASA Astrophysics Data System (ADS)

    Krepper, Carlos M.; García, Norberto O.; Jones, Phil D.

    2006-07-01

    The use of river flow as a surrogate to study climatic variability implies the assumption that changes in rainfall are mirrored and likely amplified in streamflow. This is probably not completely true in large basins, particularly those that encompass different climatic regions, like the Paraguay river basin. Not all the signals present in precipitation are reflected in river flow and vice versa. The complex relationship between precipitation and streamflow could filter some signals and introduce new oscillatory modes in the discharge series. In this study the whole basin (1 095 000 km2) was divided into two sub-basins. The upper basin is upstream of the confluence with the River Apa and the lower basin is between the Apa river confluence and the Puerto Bermejo measuring station. The rainfall contribution shows a clear wet season from October to March and a dry season from April to September. A singular spectrum analysis (SSA) shows that there are trends in rainfall contributions over the upper and lower basins. Meanwhile, the lower basin only presents a near-decadal cycle (T 10 years). To determine the flow response to seasonal rainfall contributions, an SSA was applied to seasonal flow discharges at Puerto Bermejo. The seasonal flows, Q(t)O-M and Q(t)A-S, present high significant modes in the low-frequency band, like positive trends. In addition, Q(t)O-M presents a near-decadal mode, but only significant at the 77% level for short window lengths (M ≤ 15 years). Really, the Paraguay river flow is not a good surrogate to study precipitation variation. The low-frequency signals play an important role in the flow behaviour, especially during extreme events from the second half of the last century onwards.

  18. Interpretation of magnetic anomalies over the Grenada Basin

    NASA Astrophysics Data System (ADS)

    Bird, Dale E.; Hall, Stuart A.; Casey, John F.; Millegan, Patrick S.

    1993-10-01

    The Grenada Basin is a back arc basin located near the eastern border of the Caribbean Plate. The basin is bounded on the west by the north-south trending Aves Ridge (a remnant island arc) and on the east by the active Lesser Antilles island arc. Although this physiography suggests that east-west extension formed the basin, magnetic anomalies over the basin exhibit predominantly east-west trends. If the observed magnetic anomalies over the basin are produced by seafloor spreading, then the orientation of extension is complex. Extension in back arc basins is roughly normal to the trench, although some basins exhibit oblique extension. Present models for the formation of the Grenada Basin vary from north-south extension through northeast-southwest extension to east-west extension. An interpretation of magnetic anomalies over the Grenada Basin supports basin development by nearly east-west extension. Low amplitude magnetic anomaly trends subparallel to the island arc magnetic anomaly trends over the southern part of the basin and the results of forward three-dimensional (3-D) magnetic modeling are consistent with this conclusion. Late Cenozoic tectonic movements may have been responsible for disrupting the magnetic signature over the northern part of the basin. On the basis of our 3-D analysis, we attribute the prominent east-west trending anomalies of the Grenada Basin to fracture zones formed during seafloor spreading at low latitude. This east-west trend is not interpreted as indicating north-south extension of the basin.

  19. Thermal evolution of the Newark basin

    SciTech Connect

    Huntoon, J.E. ); Furlong, K.P. )

    1992-09-01

    A one-dimensional conductive thermal model is used to calculate the transient thermal history of the Newark basin, a Triassic-Jurassic continental rift basin in the eastern United States that formed during the separation of North America and Africa. The model accounts for deposition, erosion, igneous activity, lithology-dependent variations in thermal conductivity, depth-dependent radiogenic heat production, and changes in heat flow through time. A burial and erosion history for the Newark basin is constructed for the modeling, including changes in heat flow through time, emplacement of Jurassic lava flows at the surface, and emplacement of the Palisades still at depth. Vitrinite-reflectance values and apatite and zircon fission-track ages, for units of both Triassic and Jurassic age, are used to constrain the models. Use of two different data sets greatly limits the number and types of models that can reproduce the observed data. Modeling results indicate that initial formation of the Newark basin is not coincident in time with a thermal event. Elevated heat flow (on the order of 130 mW/m[sup 2] in the models) did affect the basin during its evolution, however, and was associated with igneous activity (at approximately 201-199.5 Ma in the models). Results of the modeling also indicate that the original sedimentary package in the Newark basin was approximately 2.5 km thicker than today.

  20. The basins on the Argentine continental margin

    SciTech Connect

    Urien, C.M.

    1996-08-01

    After the stabilization of the central Gondwana Craton, orogenic belts were accreted, as a result of convergence events and an extensive passive margin developed in southwestern Gondwana. Thermal subsidence in Parana, Karoo-Ventania basins and the Late Paleozoic-Early Mesozoic rifts, were modified by the Gondwana breakup and the South Atlantic opening. Early Paleozoic marine transgressions deposited the Table Mountain Group in Ventania. In southwestern Patagonia foreland clastics were deposited. Magmatic arcs and marine units indicate a tectonic trough was formed, alternating with continental sequences, over Late Paleozoic metamorphics and intrusives, resulting from plastered terrains along the Gondwana margin. In Patagonia, Permo-Carboniferous continental and glacio marine clastics infill the basins, while in Ventania, paralic sequences, grade from neritic to continental to the northeast, extending beneath the continental margin. The Triassic-Jurassic rift basins progressed onto regional widespread acid lavas and were infilled by lagoonal organic-rich sequences. Early drift phase built basins transverse to the margin, with fluvio-lacustrine sequences: Salado, Colorado, Valdes-Rawson, San Julian and North Malvinas intracratonic basins, which underwent transtensional faulting. Post-Oxfordian to Neocomian brackish sequences, onlapped the conjugate basins during the margin`s drift, with petroleum systems, as in Austral and Malvinas. In the Valanginian, basic extrusions commenced to form on the continental border, heralding the oceanic phase. Due to thermal subsidence, offlaping sediments prograded onto the remaining half-grabens. Several petroleum systems, proven and hypothetical, are identified in this region.

  1. The East Falcon Basin: Its Caribbean roots

    SciTech Connect

    Bartok, P.; Boesi, T.

    1996-08-01

    The East Falcon Basin has been described persistently in the context of the Maracaibo Basin tectonic framework. It is the objective of the present study to demonstrate that the Falcon Basin is, in effect, a Caribbean basin juxtaposed on South America and affected by Caribbean tectonics. The oldest rocks outcropping in the region are Late Paleozoic metamorphic and igneous rocks rafted from northcentral Colombia, Middle Jurassic ophiolite complexes, sediments and metasediments and Cretaceous ophiolites transported by a melange of late Cretaceous to early Tertiary sediments. The south vergence of the Caribbean Nappe province has been documented and extends to the present limit of the Andean uplift and to the southern limit of the Coastal Range. The migrating foredeep that developed during the Paleocene-Eocene deposited dominantly basinal shales and thin sandstones. During the Oligocene the Caribbean faults of the Oca system and conjugates began with a dominantly transtensional regime becoming progressively transpressional by Miocene time. The facies development of the Oligocene-Miocene documents the tectonic history. Unique blocks remained as resistant blocks creating ramparts and modifying the basin configuration. During transpression northward-verging thrusting progressively migrated towards the present coastline. The most evident structures of the region are Caribbean in affinity and combined with the sedimentary history of the region can serve to unravel the complex Caribbean-South American plate interaction.

  2. Geothermal resources of California sedimentary basins

    USGS Publications Warehouse

    Williams, C.F.; Grubb, F.V.; Galanis, S.P.

    2004-01-01

    The 2004 Department of Energy (DOE) Strategic Plan for geothermal energy calls for expanding the geothermal resource base of the United States to 40,000 MW of electric power generating potential. This will require advances in technologies for exploiting unconventional geothermal resources, including Enhanced Geothermal Systems (EGS) and geopressured geothermal. An investigation of thermal conditions in California sedimentary basins through new temperature and heat flow measurements reveals significant geothermal potential in some areas. In many of the basins, the combined cooling effects of recent tectonic and sedimentary processes result in relatively low (<60 mW/m2) heat flow and geothermal gradients. For example, temperatures in the upper 3 km of San Joaquin, Sacramento and Ventura basins are typically less than 125??C and do not reach 200??c by 5 km. By contrast, in the Cuyama, Santa Maria and western Los Angeles basins, heat flow exceeds 80 mW/m2 and temperatures near or above 200??C occur at 4 to 5 km depth, which represents thermal conditions equivalent to or hotter than those encountered at the Soultz EGS geothermal site in Europe. Although the extractable geothermal energy contained in these basins is not large relative to the major California producing geothermal fields at The Geysers or Salton Sea, the collocation in the Los Angeles basin of a substantial petroleum extraction infrastructure and a major metropolitan area may make it attractive for eventual geothermal development as EGS technology matures.

  3. Seismic stratigraphy or Cape Sorell Basin, Tasmania

    SciTech Connect

    Bellow, T.L.

    1990-05-01

    Because large new exploration areas have become scarce, the Cape Sorell basin has become an increasingly attractive frontier area. Cape Sorell basin, located along the western passive continental margin of Tasmania formed as a result of the breakup of eastern Gondwanaland 95{plus minus}5 Ma. An extensional fault system trending west-northwest with dip-slip movement down to the south-southwest forms the northern boundary and a second fault system trending north-northwest with oblique slip down to the south-southwest creates the basin. Second order extensional faults within the basin have created wrench-type flower structures, which are potential migration pathways for hydrocarbons. Nine distinct depositional sequences identified within the Cape Sorell basin record the evolution of this passive continental margin. Late Cretaceous-early Paleocene sequences were deposited as the rifting ceased and clastic progradation over the rift terrain began. Relative lowering of sea level occurred during the Paleocene, resulting in extensive channeling of the Late Cretaceous-early Paleocene sequences. A subsequent rise in relative sea level resulted in canyon-fill deposition during the early Paleocene to early Eocene. During the Eocene, sedimentation sufficiently increased to produce a downlapping sediment progradation characterized by deltaic depositional environment. Although interrupted several times by changes in relative sea level and shifting sediment sources, deltaic deposition continued until the late Oligocene. As the rate of clastic sedimentation slowed, carbonate shelf deposition began and has typified the basin since late the Oligocene.

  4. Estimating tectonic history through basin simulation-enhanced seismic inversion: geoinfomatics for sedimentary basins

    NASA Astrophysics Data System (ADS)

    Tandon, Kush; Tuncay, Kagan; Hubbard, Kyle; Comer, John; Ortoleva, Peter

    2004-01-01

    A data assimilation approach is demonstrated whereby seismic inversion is both automated and enhanced using a comprehensive numerical sedimentary basin simulator to study the physics and chemistry of sedimentary basin processes in response to geothermal gradient in much greater detail than previously attempted. The approach not only reduces costs by integrating the basin analysis and seismic inversion activities to understand the sedimentary basin evolution with respect to geodynamic parameters-but the technique also has the potential for serving as a geoinfomatics platform for understanding various physical and chemical processes operating at different scales within a sedimentary basin. Tectonic history has a first-order effect on the physical and chemical processes that govern the evolution of sedimentary basins. We demonstrate how such tectonic parameters may be estimated by minimizing the difference between observed seismic reflection data and synthetic ones constructed from the output of a reaction, transport, mechanical (RTM) basin model. We demonstrate the method by reconstructing the geothermal gradient. As thermal history strongly affects the rate of RTM processes operating in a sedimentary basin, variations in geothermal gradient history alter the present-day fluid pressure, effective stress, porosity, fracture statistics and hydrocarbon distribution. All these properties, in turn, affect the mechanical wave velocity and sediment density profiles for a sedimentary basin. The present-day state of the sedimentary basin is imaged by reflection seismology data to a high degree of resolution, but it does not give any indication of the processes that contributed to the evolution of the basin or causes for heterogeneities within the basin that are being imaged. Using texture and fluid properties predicted by our Basin RTM simulator, we generate synthetic seismograms. Linear correlation using power spectra as an error measure and an efficient quadratic

  5. Estimating tectonic history through basin simulation-enhanced seismic inversion: Geoinformatics for sedimentary basins

    USGS Publications Warehouse

    Tandon, K.; Tuncay, K.; Hubbard, K.; Comer, J.; Ortoleva, P.

    2004-01-01

    A data assimilation approach is demonstrated whereby seismic inversion is both automated and enhanced using a comprehensive numerical sedimentary basin simulator to study the physics and chemistry of sedimentary basin processes in response to geothermal gradient in much greater detail than previously attempted. The approach not only reduces costs by integrating the basin analysis and seismic inversion activities to understand the sedimentary basin evolution with respect to geodynamic parameters-but the technique also has the potential for serving as a geoinfomatics platform for understanding various physical and chemical processes operating at different scales within a sedimentary basin. Tectonic history has a first-order effect on the physical and chemical processes that govern the evolution of sedimentary basins. We demonstrate how such tectonic parameters may be estimated by minimizing the difference between observed seismic reflection data and synthetic ones constructed from the output of a reaction, transport, mechanical (RTM) basin model. We demonstrate the method by reconstructing the geothermal gradient. As thermal history strongly affects the rate of RTM processes operating in a sedimentary basin, variations in geothermal gradient history alter the present-day fluid pressure, effective stress, porosity, fracture statistics and hydrocarbon distribution. All these properties, in turn, affect the mechanical wave velocity and sediment density profiles for a sedimentary basin. The present-day state of the sedimentary basin is imaged by reflection seismology data to a high degree of resolution, but it does not give any indication of the processes that contributed to the evolution of the basin or causes for heterogeneities within the basin that are being imaged. Using texture and fluid properties predicted by our Basin RTM simulator, we generate synthetic seismograms. Linear correlation using power spectra as an error measure and an efficient quadratic

  6. On Restoring Sedimentary Basins for Post-Depositional Deformation - Paleozoic Basins of the Central Andes

    NASA Astrophysics Data System (ADS)

    Bahlburg, H.

    2015-12-01

    The reconstruction and interpretation of sedimentary basins incorporated into folded and thrusted mountain belts is strongly limited by the style and intensity of shortening. This problem is exacerbated if deformation is polyphasic as is the case for the Paleozoic basins in the central Andes. Some of these have been deformed by folding and thrusting during at least 3 events in the Late Ordovician, the Late Paleozoic and Cenozoic. A realistic reconstruction of the original basin dimensions and geometries from outcrops and maps appears to be almost impossible. We present results of a stepwise reconstruction of the Paleozoic basins of the central Andes by restoring basin areas and fills accounting for crustal shortening. The structurally most prominent feature of the central Andes is the Bolivian Orocline which accomodated shortening in the last 45 Ma on the order of between 300 and 500 km. In a first step basins were restored by accounting for Cenozoic rotation and shortening by deconvolving the basins using an enhanced version of the oroclinal bending model of Ariagada et al. (2008). Results were then restored stepwise for older deformation. Constraints on these subsequent steps are significantly poorer as values of shortening can be derived only from folds and thusts apparent in outcrops. The amount of shortening accomodated on unexposed and therefore unknown thrusts can not be quantified and is a significant source of error very likely leading to an underestimation of the amount of shortening. Accepting these limitations, basin restoration results in an increase in basin area by ≥100%. The volumes of stratigraphically controlled basin fills can now be redistributed over the wider, restored area, translating into smaller rates of accumulation and hence required subsidence. The restored rates conform to those of equivalent modern basin settings and permit a more realistic and actualistic analysis of subsidence drivers and the respective tectonic framework.

  7. Active transtensional intracontinental basins: Walker Lane in the western Great Basin

    USGS Publications Warehouse

    Jayko, Angela S.; Bursik, Marcus

    2012-01-01

    The geometry and dimensions of sedimentary basins within the Walker Lane are a result of Plio-Pleistocene transtensive deformation and partial detachment of the Sierra Nevada crustal block from the North American plate. Distinct morpho-tectonic domains lie within this active transtensive zone. The northeast end of the Walker Lane is partly buried by active volcanism of the southern Cascades, and adjacent basins are filled or poorly developed. To the south, the basin sizes are moderate, 25–45km × 15–10 km, with narrow 8-12km wide mountain ranges mainly oriented N-S to NNE. These basins form subparallel arrays in discrete zones trending about 300° and have documented clockwise rotation. This is succeeded to the south by a releasing stepover domain ∼85-100km wide, where the basins are elongated E-W to ENE, small (∼15-30km long, 5-15km wide), and locally occupied by active volcanic centers. The southernmost part of the Walker Lane is structurally integrated, with high to extreme relief. Adjacent basins are elongate, 50-200km long and ∼5 -20km wide. Variations in transtensive basin orientations in the Walker Lane are largely attributable to variations in strain partitioning. Large basins in the Walker Lane have 2-6km displacement across basin bounding faults with up to 3 km of clastic accumulation based on gravity and drill hole data. The sedimentary deposits of the basins may include interbedded volcanic deposits with bimodal basaltic and rhyolitic associations. The basins may include lacustrine deposits that record a wide range of water chemistry from cold fresh water conditions to saline-evaporative

  8. Mesozoic evolution of the Amu Darya basin

    NASA Astrophysics Data System (ADS)

    Brunet, Marie-Françoise; Ershov, Andrey; Korotaev, Maxim; Mordvintsev, Dmitriy; Barrier, Eric; Sidorova, Irina

    2014-05-01

    This study, granted by the Darius Programme, aims at proposing a model of tectono-stratigraphic evolution of the Amu Darya basin since the Late Palaeozoic and to understand the relationship with the nearby basins. The Amu Darya basin, as its close eastern neighbour, the Afghan-Tajik basin, lies on the Turan platform, after the closure of the Turkestan Ocean during the Late Paleozoic. These two basins, spread on mainly lowlands of Turkmenistan, southwest Uzbekistan, Tajikistan, and northern Afghanistan, are separated from one another by the South-Western Gissar meganticline, where series of the northern Amu Darya margin are outcropping. The evolution is closely controlled by several periods of crustal thinning (post-collision rifting and back-arc extension), with some marine incursions, coming in between accretions of continental blocks and collisions that succeeded from the Late Triassic-Early Jurassic (Eo-Cimmerian orogeny) to the Cenozoic times. These orogenies controlled the deposition of thick clastics sequences, and the collision of the Indian Plate with Eurasia strongly deformed the sedimentary cover of the Afghan-Tajik basin. The more than 7 km thick Meso-Cenozoic sedimentary succession of the Amu Darya basin, lies on a complex system of rifts and blocks. Their orientation and age (late Permian, Triassic?) are not well known because of deep burial. The north-eastern margin, with the Bukhara (upper margin) and Chardzhou steps, is NW oriented, parallel to the Paleozoic Turkestan suture. The orientation bends to W-E, in the part of the Gissar situated to the North of the Afghan-Tajik basin. This EW trending orientation prevails also in the south(-eastern) margin of the basin (series of North Afghanistan highs) and in the Murgab depression, the south-eastern deepest portion of the Amu Darya basin. It is in this area and in the eastern part of the Amu Darya basin that the Jurassic as well as the lower Cretaceous sediments are the thickest. The south-western part

  9. The chromatin assembly factor 1 promotes Rad51-dependent template switches at replication forks by counteracting D-loop disassembly by the RecQ-type helicase Rqh1.

    PubMed

    Pietrobon, Violena; Fréon, Karine; Hardy, Julien; Costes, Audrey; Iraqui, Ismail; Ochsenbein, Françoise; Lambert, Sarah A E

    2014-10-01

    At blocked replication forks, homologous recombination mediates the nascent strands to switch template in order to ensure replication restart, but faulty template switches underlie genome rearrangements in cancer cells and genomic disorders. Recombination occurs within DNA packaged into chromatin that must first be relaxed and then restored when recombination is completed. The chromatin assembly factor 1, CAF-1, is a histone H3-H4 chaperone involved in DNA synthesis-coupled chromatin assembly during DNA replication and DNA repair. We reveal a novel chromatin factor-dependent step during replication-coupled DNA repair: Fission yeast CAF-1 promotes Rad51-dependent template switches at replication forks, independently of the postreplication repair pathway. We used a physical assay that allows the analysis of the individual steps of template switch, from the recruitment of recombination factors to the formation of joint molecules, combined with a quantitative measure of the resulting rearrangements. We reveal functional and physical interplays between CAF-1 and the RecQ-helicase Rqh1, the BLM homologue, mutations in which cause Bloom's syndrome, a human disease associating genome instability with cancer predisposition. We establish that CAF-1 promotes template switch by counteracting D-loop disassembly by Rqh1. Consequently, the likelihood of faulty template switches is controlled by antagonistic activities of CAF-1 and Rqh1 in the stability of the D-loop. D-loop stabilization requires the ability of CAF-1 to interact with PCNA and is thus linked to the DNA synthesis step. We propose that CAF-1 plays a regulatory role during template switch by assembling chromatin on the D-loop and thereby impacting the resolution of the D-loop.

  10. A new survey of multiring impact basins on Mars

    NASA Technical Reports Server (NTRS)

    Schultz, Richard A.; Frey, Herbert V.

    1990-01-01

    Literature data on Martian multiring impact basins with diameters greater than 500 km are summarized, and evidence is found for eight new such basins. The pattern of changes of basin morphology with increasing basin size suggests three subclasses of multiring basins: (1) multiring basins with diameters up to about 1850 km, which are characterized by the Orientale type concentric structure and cumulative frequency power law slope of -0.75; (2) the Argyre-type basins (with diameters between 1850 and 3600 km, defined by rugged concentric annnuli and a power law slope of nearly -2.0; and (3) the Chryse-type basins (with diameters greater than 3600 km), which exhibit multiple concentric rings and very shallow topographic profiles. Multiring basins are found in all parts of Mars, including the northern lowlands, Tharsis, and surrounding highlands, and are associated with much of the subsequent resurfacing of cratered terrain.

  11. The long wavelength topography of Beethoven and Tolstoj basins, Mercury

    NASA Astrophysics Data System (ADS)

    André, Sarah L.; Watters, Thomas R.; Robinson, Mark S.

    2005-11-01

    Topography derived from Mariner 10 stereo images is used to characterize the interior structure of two mercurian basins, Beethoven and Tolstoj. Beethoven and Tolstoj basins are shallow (~2.5 km and ~2 km deep, respectively) and relatively flat-floored. Beethoven basin has an interior topographic rise near the northwest margin. The topography of Beethoven and Tolstoj basins is similar to that of lunar mare-filled basins. Well-developed basin-concentric wrinkle ridges and arcuate graben associated with lunar mascons are absent in both Beethoven and Tolstoj basins. The lack of mascon tectonic features suggests that either 1) the mercurian basins have a relatively thin veneer of fill material, 2) Mercury's elastic lithosphere was too strong for significant lithospheric flexure and subsidence to occur, or 3) the basin fill material has little or no density contrast with the surrounding crust and thus exerts little net load on the mercurian lithosphere.

  12. Perspective of gas exploration in Ying-Qiong Basin

    SciTech Connect

    He, Hanyi; Zhongtiang Hu )

    1996-01-01

    The Yinggehai and Qiongdongnan Basin (Ying-Qiong Basin) in the northwest part of the South China Sea is a Cenozoic sedimentary basin, which has fast-subsiding and thick sediments. The maximum Cenozoic sediments in the center part of the basin is 20,000 m. Six sets of source rocks with prevailing Type III kerogen were developed in the basin, which has a great potential for gas generation. Different types of reservoirs and traps, leading to different assemblages of source rocks, reservoirs, and cap rocks, form good gas pools. Abnormal high temperature and high pressure in the basin resulted in many mud diapirs and made the generation, migration, and accumulation of gas more colorful. Up to now, four gas fields have been discovered in the basin. A large number of anticlines and stratigraphic-lithologic traps in the basin provide an extensive area for gas exploration. The perspective of gas exploration in the basin is vast and bright.

  13. Perspective of gas exploration in Ying-Qiong Basin

    SciTech Connect

    He, Hanyi; Zhongtiang Hu

    1996-12-31

    The Yinggehai and Qiongdongnan Basin (Ying-Qiong Basin) in the northwest part of the South China Sea is a Cenozoic sedimentary basin, which has fast-subsiding and thick sediments. The maximum Cenozoic sediments in the center part of the basin is 20,000 m. Six sets of source rocks with prevailing Type III kerogen were developed in the basin, which has a great potential for gas generation. Different types of reservoirs and traps, leading to different assemblages of source rocks, reservoirs, and cap rocks, form good gas pools. Abnormal high temperature and high pressure in the basin resulted in many mud diapirs and made the generation, migration, and accumulation of gas more colorful. Up to now, four gas fields have been discovered in the basin. A large number of anticlines and stratigraphic-lithologic traps in the basin provide an extensive area for gas exploration. The perspective of gas exploration in the basin is vast and bright.

  14. Precambrian shield and basement tectonics in sedimentary basin analysis

    SciTech Connect

    Touborg, J.F.

    1984-04-01

    This study focused on the use of (1) regional structural analysis of basement and Precambrian rocks surrounding a sedimentary basin, and (2) tracing basement structures into the sedimentary basin. The structural analysis of the Precambrian shield has a fundamental bearing on interpretation of overlying sedimentary cover rocks. This is expressed in the southern part of the Hudson's Bay basin and its southeastern arm, the Moose River basin. For instance, the rims of both basins are controlled by faults or graben structures. Approximately 13 major fault systems with strike lengths of 200-300 km (125-186 mi) or more can be traced from the exposed Precambrian shield into the basin in terms of lineament arrays and/or aeromagnetic and/or gravity signature. The data suggest reactivation of faults during basin sedimentation. This type of basement structural analysis in areas adjacent to sedimentary basins can provide a valuable interpretation base for subsequent seismic surveys and basin evaluation.

  15. Tularosa Basin Play Fairway Analysis: Partial Basin and Range Heat and Zones of Critical Stress Maps

    DOE Data Explorer

    Adam Brandt

    2015-11-15

    Interpolated maps of heat flow, temperature gradient, and quartz geothermometers are included as TIF files. Zones of critical stress map is also included as a TIF file. The zones are given a 5km diameter buffer. The study area is only a part of the Basin and Range, but it does includes the Tularosa Basin.

  16. Implication of drainage basin parameters of a tropical river basin of South India

    NASA Astrophysics Data System (ADS)

    Babu, K. J.; Sreekumar, S.; Aslam, Arish

    2016-03-01

    Drainage morphometry provides quantitative description of the drainage system which is an important aspect of the characterisation of watersheds. Chalakudi River is one of the important rivers of the South India which has attracted attention of many environmental scientists recently because of the proposed Athirapally Hydel Project across the river. SRTM (Shuttle Radar Topographic Mission) data were used for preparing DEM (Digital Elevation Model), Aspect Map and Slope Map. Geographical Information System (GIS) was used for the evaluation of linear, areal and relief aspects of morphometric parameters. The study reveals that the terrain exhibits dentritic and trellis pattern of drainage. The Chalakudi River Basin has a total area of 1,448.73 km2 and is designated as seventh-order basin. The drainage density of the basin is estimated as 2.54 and the lower-order streams mostly dominate the basin. The high basin relief indicates high runoff and sediment transport. The elongation ratio of the Chalakudi Basin is estimated as 0.48 and indicates that the shape of the basin is elongated. The development of stream segments in the basin area is more or less effected by rainfall. Relief ratio indicates that the discharge capability of watershed is very high and the groundwater potential is meagre. The low value of drainage density in spite of mountainous relief indicates that the area is covered by dense vegetation and resistant rocks permeated by fractures and joints. These studies are helpful in watershed development planning and wise utilization of natural resources.

  17. Hydrocarbon systems in the East Texas basin: A basin modeling approach

    SciTech Connect

    Wescott, W.A.; Hood, W.C. )

    1993-09-01

    The East Texas basin is a prolific mature hydrocarbon province, producing oil and gas from several reservoirs and a variety of trap types. Much of the liquid hydrocarbons discovered in the basin are trapped in structures related to movement of the underlying Louann Salt. By determining the structural evolution of the basin, a framework was constructed to model the generation of hydrocarbons in the basin. Geochemical data indicate three major source horizons: the Smackover formation (Jurassic oil), shales in the Pearsal Group (Lower Cretaceous oil), and the Eagleford shale (Upper Cretaceous oil). The Jurassic source is mature throughout the basin and began to expel oil approximately 88 Ma. The distribution of Jurassic oil in Cretaceous reservoirs shows that vertical migration routes predominated. Lower Cretaceous source rocks are mature only in the deep, central part of the basin where expulsion began around 47 Ma Distribution of this oil type suggests that Lower Cretaceous source rocks occur only in localized areas of the East Texas basin. The Eagleford shale is immature in the main part of the basin, but it is mature south of the Angelina-Caldwell flexure, where is reached peak generation approximately 20 Ma. Lateral migration explains the distribution of this oil. Migration routes to the giant East Texas field may be 60 mi or more.

  18. Chlorofluorocarbon distributions in the deep Argentine Basin

    SciTech Connect

    Warner, M.J. ); Weiss, R.F. ); Smethie, W.M. Jr. )

    1990-01-09

    The seawater concentrations of the chlorofluorocarbons (CFCs) F-11 and F-12 were measured in the Argentine Basin during the Abyssal Boundary Current Studies (1986) and the South Atlantic Ventilation Experiment (1988-89) expeditions. In most regions of the basin, the CFC concentrations are above the detection limit (0.015 pmol/kg) in the entire water column. The main features of the F-11 and F-12 profiles in the deep waters of the Argentine Basin are concentration mixima at depths of 2 to 3 km and generally increasing concentrations towards the bottom. The mid-depth CFC minima are associated with the salinity maximum of Circumpolar Deep Water (CDW). The higher CFC concentrations at the seafloor are correlated with the colder temperatures of Antarctic Bottom Water (AABW). The CFC concentrations in AABW are highest on the eastern portion of the basin along 47[degrees]S and along the southern and western boundaries. These distributions are consistent with a separation of the inflowing AABW into a cyclonic gyre in the eastern portion of the basin and a western boundary current which carries a detectable CFC singal as far noth as 17[degrees]S. Between CDW and AABW, there are local CFC maxima and minima which are not associated with extrema in other hydrographic properties. The local minima are found on a mean density of 46.07 [sigma][sub 4], which is the upper bound of the water entering the Argentine Basin from the Weddell Sea (Reid, Deep-Sea Res., 1989 submitted). The local CFC maxima are found at about the 46.00 [sigma][sub 4] isopycnal surface. Water of this density apparently is of circumpolar origin. The presence of these local CFC extrema in this density range carries information on the time-dependent vertical mixing in the deep Argentine Basin.

  19. Petroleum in the Junggar basin, northwestern China

    NASA Astrophysics Data System (ADS)

    Taner, Irfan; Kamen-Kaye, Maurice; Meyerhoff, Arthur A.

    The Junggar basin occupies a large triangular area of some 130 000 km 2 in northwestern China. Situated between the Altay Shan (Altay Range) on the northeast and the Tian Shan (Tian Range) on the southwest, and between lesser ranges around the remainder of its periphery, the Junggar basin is completely intermontane. Its history as a basin began in the Permian, and continued as various uplifts and downwarps evolved. Through the Paleozoic the characteristics of the Junggar basin area were largely geosynclinal and marine. Its post-Permian development took place exclusively in continental regimes. Inhabitants of the Junggar basin have known and utilized its numerous oil and asphalt seeps and its spectacular spreads of asphalt for more than 2000 years, especially in the Karamay-Urho thrust belt near the northwestern rim. The first discovery of oil in the modern sense came at Dushanzi, one of the steeply folded anticlines of theÜrümqi foredeep near the southern rim. The first shallow oil in the Karamay-Urho thrust belt came in 1937, followed by commercial production in the Karamay field in 1955. Output continued to be modest until wells were drilled through local thrusts and reverse faults in the early 1980s. By 1985, cumulative production of the Karamay group of fields had reached 42,000,000 t (metric tonnes) (306,000,000 bbl), with a calculated minimum ultimate recovery of 280,000,000 t (2 billion bbl). Principal production comes from Permian and Triassic strata in continental facies. Apart from marine Mid and Upper Carboniferous strata, source rocks occur mainly in fine-grained lacustrine detrital beds of the Permian, the Triassic, the Jurassic and the Tertiary. Several uplifts and downwarps elsewhere in the Junggar basin remain to be drilled comprehensively. Results from such drilling may enhance the very important position that the Junggar already has attained in the hierarchy of China's onshore basins.

  20. Kandik basin stratigraphy, sedimentology, and structure

    SciTech Connect

    Wiley, T.J.; Howell, D.G.; Kauffman-Linam, L.; Boundy-Sanders, S.; Murray, R.W.; Jones, D.L.

    1987-05-01

    East-central Alaska's Kandik basin is a structural remnant of a larger Permian to Cretaceous basin. Permian shallow-water Tahkandit Limestone and Step Conglomerate at the base of the sequence rest unconformably on Paleozoic chert-pebble conglomerate, siliceous shale, and limestone. These Permian rocks are overlain by Triassic to Lower Cretaceous open-ocean Glenn Shale, which grades upward into Lower Cretaceous (Valanginian) hummocky cross-bedded (outer shelf to upper slope) Keenan Quartzite. The quartzite grades upward into fine-grained north-northeast-flowing turbidites of the Biederman Argillite (undated). East-northeast-flowing pebbly turbidites of the Kathul Graywacke (undated) overlie Biederman strata. Locally, Cretaceous (Albian and younger) through Paleogene nonmarine rocks unconformably overlie the Kandik basin sequence. The Mesozoic part of the sequence is similar to that of Manley basin, northwest Yukon Territory, and much of the North Slope. East-directed flow for Kandik basin strata may require paleogeographic reconstructions involving local to large-scale palinspastic rotations or a western source of chert detritus. Deformation of the Mesozoic sequence in Kandik basin west of the US-Canada border shows northwest-southeast shortening. Shaly units are tightly folded with well-developed cleavage striking northeast. Strikes of beds swing from northeast to east in the extreme southwestern part of the basin, suggesting clockwise rotation. Thrust faults, reverse faults, and fold axes trend east to northeast; normal faults trend northwest. These relations are all consistent with, and probably are closely related to, right slip on the west-northwest-trending Tintina fault.

  1. Quantifying mesoscale eddies in the Lofoten Basin

    NASA Astrophysics Data System (ADS)

    Raj, R. P.; Johannessen, J. A.; Eldevik, T.; Nilsen, J. E. Ø.; Halo, I.

    2016-07-01

    The Lofoten Basin is the most eddy rich region in the Norwegian Sea. In this paper, the characteristics of these eddies are investigated from a comprehensive database of nearly two decades of satellite altimeter data (1995-2013) together with Argo profiling floats and surface drifter data. An automated method identified 1695/1666 individual anticyclonic/cyclonic eddies in the Lofoten Basin from more than 10,000 altimeter-based eddy observations. The eddies are found to be predominantly generated and residing locally. The spatial distributions of lifetime, occurrence, generation sites, size, intensity, and drift of the eddies are studied in detail. The anticyclonic eddies in the Lofoten Basin are the most long-lived eddies (>60 days), especially in the western part of the basin. We reveal two hotspots of eddy occurrence on either side of the Lofoten Basin. Furthermore, we infer a cyclonic drift of eddies in the western Lofoten Basin. Barotropic energy conversion rates reveals energy transfer from the slope current to the eddies during winter. An automated colocation of surface drifters trapped inside the altimeter-based eddies are used to corroborate the orbital speed of the anticyclonic and cyclonic eddies. Moreover, the vertical structure of the altimeter-based eddies is examined using colocated Argo profiling float profiles. Combination of altimetry, Argo floats, and surface drifter data is therefore considered to be a promising observation-based approach for further studies of the role of eddies in transport of heat and biomass from the slope current to the Lofoten Basin.

  2. Effect of basin physical characteristics on solute fluxes in nine alpine/subalpine basins, Colorado, USA

    USGS Publications Warehouse

    Sueker, J.K.; Clow, D.W.; Ryan, J.N.; Jarrett, R.D.

    2001-01-01

    Alpine/subalpine basins may exhibit substantial variability in solute fluxes despite many apparent similarities in basin characteristics. An evaluation of controls on spatial patterns in solute fluxes may allow development of predictive tools for assessing basin sensitivity to outside perturbations such as climate change or deposition of atmospheric pollutants. Relationships between basin physical characteristics, determined from geographical information system (GIS) tools, and solute fluxes and mineral weathering rates were explored for nine alpine/subalpine basins in Rocky Mountain National Park, Colorado, using correlation analyses for 1993 and 1994 data. Stream-water nitrate fluxes were correlated positively with basin characteristics associated with the talus environment; i.e., the fractional amounts of steep slopes (??? 30??), unvegetated terrain and young debris (primarily Holocene till) in the basins, and were correlated negatively with fractional amounts of subalpine meadow terrain. Correlations with nitrate indicate the importance of the talus environment in promoting nitrate flux and the mitigating effect of areas with established vegetation, such as subalpine meadows. Total mineral weathering rates for the basins ranged from about 300 to 600 mol ha-1 year -1. Oligoclase weathering accounted for 30 to 73% of the total mineral weathering flux, and was positively correlated with the amount of old debris (primarily Pleistocene glacial till) in the basins. Although calcite is found in trace amounts in bedrock, calcite weathering accounted for up to 44% of the total mineral weathering flux. Calcite was strongly correlated with steep slope, unvegetated terrain, and young debris-probably because physical weathering in steep-gradient areas exposes fresh mineral surfaces that contain calcite for chemical weathering. Oligoclase and calcite weathering are the dominant sources of alkalinity in the basins. However, atmospherically deposited acids consume much of the

  3. Potential for deep basin-centered gas accumulation in Hanna Basin, Wyoming

    USGS Publications Warehouse

    Wilson, Michael S.; Dyman, Thaddeus S.; Nuccio, Vito F.

    2001-01-01

    The potential for a continuous-type basin-centered gas accumulation in the Hanna Basin in Carbon County, Wyoming, is evaluated using geologic and production data including mud-weight, hydrocarbon-show, formation-test, bottom-hole-temperature, and vitrinite reflectance data from 29 exploratory wells. This limited data set supports the presence of a hypothetical basin-centered gas play in the Hanna Basin. Two generalized structural cross sections illustrate our interpretations of possible abnormally pressured compartments. Data indicate that a gas-charged, overpressured interval may occur within the Cretaceous Mowry, Frontier, and Niobrara Formations at depths below 10,000 ft along the southern and western margins of the basin. Overpressuring may also occur near the basin center within the Steele Shale and lower Mesaverde Group section at depths below 18,000 to 20,000 ft. However, the deepest wells drilled to date (12,000 to 15,300 ft) have not encountered over-pressure in the basin center. This overpressured zone is likely to be relatively small (probably 20 to 25 miles in diameter) and is probably depleted of gas near major basement reverse faults and outcrops where gas may have escaped. Water may have invaded reservoirs through outcrops and fracture zones along the basin margins, creating an extensive normally pressured zone. A zone of subnormal pressure also may exist below the water-saturated, normal-pressure zone and above the central zone of overpressure. Subnormal pressures have been interpreted in the center of the Hanna Basin at depths ranging from 10,000 to 25,000 ft based on indirect evidence including lost-circulation zones. Three wells on the south side of the basin, where the top of the subnormally pressured zone is interpreted to cut across stratigraphic boundaries, tested the Niobrara Formation and recovered gas and oil shows with very low shut-in pressures.

  4. Desert basins of the Southwest

    USGS Publications Warehouse

    Leake, Stanley A.; Konieczki, Alice D.; Rees, Julie A.H.

    2000-01-01

    Ground water is among the Nation’s most important natural resources. It provides drinking water to urban and rural communities, supports irrigation and industry, sustains the flow of streams and rivers, and maintains riparian and wetland ecosystems. In many areas of the Nation, the future sustainability of ground-water resources is at risk from overuse and contamination. Because ground-water systems typically respond slowly to human actions, a long-term perspective is needed to manage this valuable resource. This publication is one in a series of fact sheets that describe ground-water-resource issues across the United States, as well as some of the activities of the U.S. Geological Survey that provide information to help others develop, manage, and protect ground-water resources in a sustainable manner. Ground-water resources in the Southwest are among the most overused in the United States. Natural recharge to aquifers is low and pumping in many areas has resulted in lowering of water tables. The consequences of large-scale removal of water from storage are becoming increasingly evident. These consequences include land subsidence; loss of springs, streams, wetlands and associated habitat; and degradation of water quality. Water managers are now seeking better ways of managing ground-water resources while looking for supplemental sources of water. This fact sheet reviews basic information on ground water in the desert basins of the Southwest. Also described are some activities of the U.S. Geological Survey (USGS) that are providing scientific information for sustainable management of ground-water resources in the Southwest. Ground-water sustainability is defined as developing and using ground water in a way that can be maintained for an indefinite time without causing unacceptable environmental, economic, or social consequences.

  5. Impact melt of the lunar Crisium multiring basin

    NASA Astrophysics Data System (ADS)

    Spudis, P. D.; Sliz, M. U.

    2017-02-01

    New geological mapping of the Crisium basin on the Moon has revealed exposures of the basin impact melt sheet. The melt sheet has a feldspathic highland composition, somewhat more mafic than the melt sheet of the Orientale basin, but less mafic than comparable deposits around the Imbrium basin. These newly recognized deposits would be ideal locations to directly sample Crisium basin impact melt, material whose study would yield insight into the composition of the lunar crust, the time of formation of the basin, and the large impact process.

  6. Multiple nested basin boundaries in nonlinear driven oscillators☆

    NASA Astrophysics Data System (ADS)

    Zhang, Yongxiang; Xie, Xiangpeng; Luo, Guanwei

    2017-03-01

    A special type of basins of attraction for high-period coexisting attractors is investigated, which basin boundaries possess multiple nested structures in a driven oscillator. We analyze the global organization of basins and discuss the mechanism for the appearance of layered structures. The unstable periodic orbits and unstable limit cycle are also detected in the oscillator. The basin organization is governed by the ordering of regular saddles and the regular saddle connections are the interrupted by the unstable limit cycle. Wada basin boundary with different Wada number is discovered. Wada basin boundaries for the hidden and rare attractors are also verified.

  7. Australia`s southeastern Bonaparte basin has plenty of potential

    SciTech Connect

    Miyazaki, S.

    1997-04-21

    Situated in the Timor Sea and Joseph Bonaparte Gulf regions, the Bonaparte basin is one of the Phanerozoic basins of what is now called the North West Shelf of Australia. This basin consists of a number of Paleozoic and Mesozoic synclines and horsts. Drilling success rate for this basin is one of the highest in Australia in the last 5 years. New opportunities are available in the southeastern Bonaparte basin, where seven vacant tracts have just been released for application for exploration permits. The paper discusses the regional geology, previous exploration activities, and potentials of the southern Petrel sub-basin and Darwin shelf.

  8. Maturation modeling in Otway Basin, Australia

    SciTech Connect

    Middleton, M.F.; Falvey, D.A.

    1983-02-01

    The Otway basin is a Jurassic to Pliocene sedimentary basin formed on the southern Australian continental margin. Its formation is associated with rifting and breakup of the Australian and Antarctic plates. Lithospheric cooling and contraction have probably produced post-breakup subsidence. Either lithospheric stretching or deep crustal metamorphism may have produced pre-breakup subsidence. These mechanisms have identifiable thermal histories. Organic diagenesis (specifically the reflectance of vitrinite in oil) is empirically determined by the thermal and depositional history of an organic sediment. Thus, the stages of hydrocarbon maturity of Otway basin sediments can be modeled. Depositional history is determined from ''geohistory analysis'' and thermal history depends on the subsidence mechanism applied to the basin. A paleo-heat-flow history derived from the deep crustal metamorphism model of subsidence produces a maturation profile with depth that is consistent with observed vitrinite reflectance data, although organic diagenesis modeling is relatively insensitive to precise details of thermal history. Depositional and maturation history modeling for the present day, 20 Ma ago, 40 Ma ago, and 60 Ma ago is applied to a seismic profile across the southern Australian continental shelf in the Otway basin as a demonstration of the projection backward in time of sedimentation and organic diagenesis.

  9. South Pole-Aitken Basin Mission (SPAM)

    NASA Astrophysics Data System (ADS)

    Weitz, C. M.; Yingst, R. A.; Minitti, M.; Head, J. W., III; Prockter, L.; Dahl, J. M.; Cooper, C. D.; Crumpler, L.; Gershman, R.; Welch, R.; Jet Propulsion LABORATORY Team

    1997-03-01

    Recent Clementine data of the farside of the moon has shown high resolution details of the South Pole-Aitken basin. The basin is over 2500 km in diameter, making it the largest impact basin thus far identified in our solar system. Estimates for the excavation depth from the basin suggest that the lower crust/upper mantle may have been reached. Clementine UVVIS data show noritic compositions and high FeO wt pct compositions, supporting that at least the lower crust may have been excavated. Because the geology of the area offers a unique opportunity to study the stratigraphy of the lunar crust at depth as well as the composition of rocks from the lunar farside, we have selected a site in the South Pole-Aitken basin for a sample return mission. Although the mission described below is currently unsuitable as a Discovery class mission, other scenarios are still possible that will reduce the mass and make the mission more feasible.

  10. Petroleum geology of Solimoes Basin, Brazil

    SciTech Connect

    Campos, J.N.P.; Meister, E.M.; Pereira, C.A.G.; Murakami, C.Y. )

    1993-02-01

    Solimoes basin is located at the northwestern portion of the South American continent, adjacent to a subandean pericratonic belt. It constitutes a Paleozoic intracratonic basin covering an area of about 600,000 km[sup 2] and displaying a maximum sedimentary thickness of 3400 m. The tectono-sedimentary evolution can be largely related with important events that occurred at the western border of the continent. The regional flexural subsidence and tectonic deformation observed are correlated to two major phases: Pre-Andean (Paleozoic) and Andean (Mesozoic and Cenozoic). In the Andean phase, compression with shear components, of Triassic age, known as the Jurua Tectonism, became very important for oil exploration of the basin. The stratigraphic conditions considered of greatest interest for petroleum exploration comprise Devonian gas and oil sourcing shales and Carboniferous sandstones reservoirs with an evaporitic seal. The main traps are anticlines related to reverse faults. In this context, Petrobras discovered Jurua gas field in 1978 and the Rio Urucu gas and oil field in 1986. These were the first fields discovered in Brazilian Paleozoic basins. Total petroleum fields discovered in Brazilian Paleozoic basins. Total petroleum reserves discovered represent 400 million bbl of equivalent oil. Present migration and accumulation call for previous accumulation in intrabasinal Paleozoic highs and related stratigraphic traps. Late tectonism seems to have resulted in redistribution and/or escape of fluids into new traps. Less disturbed areas are expected to contain original accumulations.

  11. Subsurface structure of the eastern Arkoma basin

    SciTech Connect

    Vanarsdale, R.B. ); Schweig, E.S. III )

    1990-07-01

    Analysis of 425 km of seismic reflection data in the eastern Arkoma basin reveals a structure and history quite different from those previously reported for the Arkoma basin. The eastern Arkoma basin has three structural styles that formed in the following chronological order: deep, steep normal faults; shallow listric normal faults; and thrust faults. The origin of the structural styles and the Paleozoic history of the eastern Arkoma basin may be summarized as follows. Late Proterozoic or Early Cambrian rifting was followed by deposition of Cambrian through Upper Mississippian strata on a passive plate margin. The Mississippian-Pennsylvanian boundary marks a time of major down-to-the-south normal faulting with coincident folding of the footwall blocks and truncation of the faulted and folded terrain by a pre-Morrowan (Mississippian-Pennsylvanian) unconformity. The unconformity slopes southward and steepens locally across the erosionally truncated footwall blocks. During the Pennsylvanian, down-to-the-south listric normal faults cut the Atokan and Morrowan sections and merged with, but did not displace, the steeper segments of the sub-Morrowan unconformity. Surface folds north of the Ross Creek thrust are rollover anticlines overlying these listric normal faults. Major deformation in the eastern Arkoma basin terminated with emplacement of the Ross Creek thrust in the Late Pennsylvanian. 4 figs., 1 tab.

  12. Hydrothermal Activity in the Northern Guaymas Basin

    NASA Astrophysics Data System (ADS)

    Berndt, C.; Hensen, C.; Mortera-Gutierrez, C. A.; Sarkar, S.; Geilert, S.; Schmidt, M.; Liebetrau, V.; Kipfer, R.; Scholz, F.; Doll, M.; Muff, S.; Karstens, J.; Böttner, C.; Chi, W. C.; Moser, M.; Behrendt, R.; Fiskal, A.; Evans, T.; Planke, S.; Lizarralde, D.; Lever, M. A.

    2015-12-01

    Rift-related magmatism in the Guaymas Basin, Gulf of California induces hydrothermal activity within the basin sediments. Mobilized fluids migrate to the seafloor where they are emitted into the water column changing ocean chemistry and fuelling chemosynthetic ecosystems. New seismic and geochemical data from the northern rift arm of the Guaymas Basin document the variety of fluid expulsion phenomena from large-scale subsurface sediment mobilization related to contact metamorphosis to focused small-scale structures. The geochemical composition of emitted fluids depends largely on the age of the fluid escape structures with respect to the underlying intrusions. Whereas, old structures are dominated by methane emission, young vent sites are characterized by hot fluids that carry a wide range of minerals in solution. The overall high geothermal gradient within the basin (mainly between 160 and 260 °C/km) leads to a thin gas hydrate stability zone. Thus, deep hydrothermal fluid advection affects the gas hydrate system and makes it more dynamic than in colder sedimentary basins.

  13. Surficial deposits in the Bear Lake Basin

    USGS Publications Warehouse

    Reheis, Marith C.; Laabs, Benjamin J.C.; Forester, Richard M.; McGeehin, John P.; Kaufman, Darrell S.; Bright, Jordon

    2005-01-01

    Mapping and dating of surficial deposits in the Bear Lake drainage basin were undertaken to provide a geologic context for interpretation of cores taken from deposits beneath Bear Lake, which sometimes receives water and sediment from the glaciated Bear River and sometimes only from the small drainage basin of Bear Lake itself. Analyses of core sediments by others are directed at (1) constructing a high-resolution climate record for the Bear Lake area during the late Pleistocene and Holocene, and (2) investigating the sources and weathering history of sediments in the drainage basin. Surficial deposits in the upper Bear River and Bear Lake drainage basins are different in their overall compositions, although they do overlap. In the upper Bear River drainage, Quaternary deposits derived from glaciation of the Uinta Range contain abundant detritus weathered from Precambrian quartzite, whereas unglaciated tributaries downstream mainly contribute finer sediment weathered from much younger, more friable sedimentary rocks. In contrast, carbonate rocks capped by a carapace of Tertiary sediments dominate the Bear Lake drainage basin.

  14. Hydrocarbon potential of lower Magdalena basin

    SciTech Connect

    Torres, E.; Valderrama, R. )

    1989-03-01

    The Lower Magdalena basin complex of Colombia has an areal extent of more than 87,000 km{sup 2}. The geologic setting of the different subbasins of the Lower Magdalena presents attractive play concepts for the generation, entrapment, and production of hydrocarbons. The sedimentary sequence within the basin attains a thickness in excess of 12,200 m, with the preponderance of this section being of Tertiary age. This major thickness of section contains good source and reservoir rocks and seals and an abundance of structural and stratigraphic traps, which make the basin attractive for new interpretation and evaluation. The Plato, San Jorge, and Sinu subbasins lie within the Lower Magdalena complex. Each of these presents different geological conditions, thereby offering a variety of play concepts for hydrocarbon exploration. Previous exploration in the Lower Magdalena has resulted in the discovery of 10 small to moderate-size fields, which have produced nearly 200 million bbl of oil. The density of exploration drilling within the basin is one well/435 km{sup 2}, thereby allowing the opportunity for more discoveries to be realized. The existence of a thick Tertiary section with excellent source beds and a tectonic history that allows for both structural and stratigraphic traps presents an excellent opportunity for the application of modern exploration techniques to reevaluate the potential of a basin that has not been thoroughly evaluated due to complex exploration problems.

  15. Petroleum prospects of Southern Nigeria's Anambra Basin

    SciTech Connect

    Avbovbo, A.A.; Ayoola, O.

    1981-05-04

    Surrounded by the Benue trough, the Middle Niger River depression, the Niger River delta, and the Abakaliki anticlinorium, Nigeria's Anambra basin probably holds a thick, unexplored sequence with significant hydrocarbon potential. The basin's sediment could be 16,000 ft thick; a Bouguer gravity survey indicates two parallel northeast-southwest trending gravity lows (the Anambra low and the Awka depression) separated by the Onitsha high. Although geologists interpret the basin as Upper Cretaceous-Lower Tertiary, its southern portion is down-warped and overlapped by the delta's thick Tertiary deposits, lowering the Cretaceous to prohibitive depths in the overlap areas; wells drilled to 16,000 ft at the delta's apex thus have not encountered the Cretaceous sediments. An evaluation of the basin's pre-Santonian hydrocarbon prospects will require a deep exploratory drilling program. As Nigeria shifts its production emphasis from oil to gas and firms up plans for an LNG plant in the Niger delta, exploration in the gas-prone Anambra basin will probably surge.

  16. Offshore Essaouira basin: Geology and hydrocarbon potential

    SciTech Connect

    Jabour, H.; Ait Salem, A. )

    1991-03-01

    The study area lies in the offshore extension of the onshore Essaouria basin. The Mesozoic development of the Essaouira margin was largely controlled by Late Triassic to Mid-Jurassic rifting and subsequent opening of the Central Atlantic, with the evolution of a typical passive, opening of the Central Atlantic, with the evolution of a typical passive, continental margin. Diapiric salt structure recognized on seismic defines a Late Triassic-Early Jurassic salt basin in the offshore area initiated during early rifting. Subsidence and sea-level rise during Jurassic resulted in carbonate platform development. This was followed during Cretaceous and Tertiary time by the deposition of a prograding siliciclastic system. Only three wells have been drilled in this basin. Although drilled on poorly defined prospects, these wells encountered gas and oil shows. Fairly extensive seismic coverage of good quality data is now available. A study based on an integrated approach involving seismic facies definition and mapping, correlation with well data, identification of the principal control on sedimentation, and basin modeling in conjunction with source rock prediction and maturity modeling has been carried out. Results have shown that hydrocarbon potential in the offshore Essaouira basin has not yet been substantiated by drilling. Attractive structural and stratigraphic prospects exist in the shelf, shelf edge, and the slope, and await confirmation by drilling.

  17. Petroleum geochemistry of the Zala basin, Hungary

    SciTech Connect

    Clayton, J.L. ); Koncz, I. )

    1994-01-01

    The Zala basin is a subbasin within the Pannonian basis on Hungary. Oil and smaller amounts of gas are produced from Upper Triassic through Miocene reservoirs. Our geochemical study of oils and rocks in the basin indicate that two, and possibly three, genetic oil types are present in the basin. Miocene source rocks, previously believed by explorationists to be the predominant source rock, have expelled minor amounts of hydrocarbons. The main source rock is the Upper Triassic (Rhaetian) Koessen Marl Formation or its stratigraphic equivalent. Oils derived from the Triassic source rock are recognizable by their isotopic and biological marker composition, and high content of metals. In other areas of Europe, Upper Triassic source rocks have been correlated with large oil accumulations (e.g., Molassa and Villafortuna fields, Po basin, and other fields in Italy) or are postulated to be good potential source rocks (e.g., Bristol channel Trough). Knowledge of the geochemical characteristics of oils derived from these Upper Triassic source rocks and understanding of the source rock distribution and maturation history are important for recognizing Triassic oil-source bed relationships and for further exploration in other basins in Hungary and other parts of Europe where Triassic source rocks are present.

  18. Exploration in the Ombilin Intermontane Basin, West Sumatra

    SciTech Connect

    Koning, T.

    1996-12-31

    The Ombilin Basin is a Tertiary intermontane basin located within the Barisan Mountain Range of Sumatra. Oil exploration commenced in the Ombilin Basin in the early 1980s when geological mapping was carried out, a synthetic aperture radar survey was flown, and a basin-wide geophysical survey was completed. This effort led to the drilling of Sinimar No. 1 to a total depth 3020 m. Sinimar No. 1 was a historic well in Indonesia`s oil industry since it was the first oil exploration well drilled in the Ombilin Basin and also the first well drilled in an intermontane basin in Indonesia. Oil, gas and condensate was tested in the well. An integrated interpretation of the well, geophysical and outcrop data indicates that despite its small areal size (30 km x 50 km), the Ombilin Basin is a deep pull-apart basin containing up to 4500 m of Tertiary sediments, ranging in age from Middle Eocene to Early Miocene. The basin currently is in an intermontane basin structural setting but it was also an intermontane basin during its Early Tertiary depositional history. During the Eocene, alluvial fans and massive debris flows were deposited on the basin margins and a large lake occupied the basin center. Fluvial deposition occurred in the basin during the Oligocene followed by deposition of marine shales, sandstones, and isolated reefs during the Miocene. Although the Ombilin Basin is located within Sumatra`s magmatic arc and is partially covered by volcanics from extinct and active volcanoes, the subsurface temperature gradients of 1.62 deg. F/100 ft. recorded in Sinimar No. I and 1.47 deg F/100 ft. measured in a deep (670 m) coal exploration core hole are significantly cooler than the average subsurface temperature gradients in the Sumatra back-arc basins. Organic-rich Eocene lacustrine shales are the likely source rocks for the hydrocarbons tested in Sinimar No. 1 and the oil seeps located along the basin margins.

  19. Exploration in the Ombilin Intermontane Basin, West Sumatra

    SciTech Connect

    Koning, T. Petroleum Co., Lagos )

    1996-01-01

    The Ombilin Basin is a Tertiary intermontane basin located within the Barisan Mountain Range of Sumatra. Oil exploration commenced in the Ombilin Basin in the early 1980s when geological mapping was carried out, a synthetic aperture radar survey was flown, and a basin-wide geophysical survey was completed. This effort led to the drilling of Sinimar No. 1 to a total depth 3020 m. Sinimar No. 1 was a historic well in Indonesia's oil industry since it was the first oil exploration well drilled in the Ombilin Basin and also the first well drilled in an intermontane basin in Indonesia. Oil, gas and condensate was tested in the well. An integrated interpretation of the well, geophysical and outcrop data indicates that despite its small areal size (30 km x 50 km), the Ombilin Basin is a deep pull-apart basin containing up to 4500 m of Tertiary sediments, ranging in age from Middle Eocene to Early Miocene. The basin currently is in an intermontane basin structural setting but it was also an intermontane basin during its Early Tertiary depositional history. During the Eocene, alluvial fans and massive debris flows were deposited on the basin margins and a large lake occupied the basin center. Fluvial deposition occurred in the basin during the Oligocene followed by deposition of marine shales, sandstones, and isolated reefs during the Miocene. Although the Ombilin Basin is located within Sumatra's magmatic arc and is partially covered by volcanics from extinct and active volcanoes, the subsurface temperature gradients of 1.62 deg. F/100 ft. recorded in Sinimar No. I and 1.47 deg F/100 ft. measured in a deep (670 m) coal exploration core hole are significantly cooler than the average subsurface temperature gradients in the Sumatra back-arc basins. Organic-rich Eocene lacustrine shales are the likely source rocks for the hydrocarbons tested in Sinimar No. 1 and the oil seeps located along the basin margins.

  20. Modified Streamflows 1990 Level of Irrigation : Missouri, Colorado, Peace and Slave River Basin, 1928-1989.

    SciTech Connect

    A.G. Crook Company; United States. Bonneville Power Administration

    1993-07-01

    This report presents data for monthly mean streamflows adjusted for storage change, evaporation, and irrigation, for the years 1928-1990, for the Colorado River Basin, the Missouri River Basin, the Peace River Basin, and the Slave River Basin.

  1. Morphometric analysis of Suketi river basin, Himachal Himalaya, India

    NASA Astrophysics Data System (ADS)

    Pophare, Anil M.; Balpande, Umesh S.

    2014-10-01

    Suketi river basin is located in the Mandi district of Himachal Pradesh, India. It encompasses a central inter-montane valley and surrounding mountainous terrain in the Lower Himachal Himalaya. Morphometric analysis of the Suketi river basin was carried out to study its drainage characteristics and overall groundwater resource potential. The entire Suketi river basin has been divided into five sub-basins based on the catchment areas of Suketi trunk stream and its major tributaries. Quantitative assessment of each sub-basin was carried out for its linear, areal, and relief aspects. The analysis reveals that the drainage network of the entire Suketi river basin constitutes a 7th order basin. Out of five sub-basins, Kansa khad sub-basin (KKSB), Gangli khad sub-basin (GKSB) and Ratti khad sub-basin (RKSB) are 5th order sub-basins. The Dadour khad sub-basin (DKSB) is 6th order sub-basin, while Suketi trunk stream sub-basin (STSSB) is a 7th order sub-basin. The entire drainage basin area reflects late youth to early mature stage of development of the fluvial geomorphic cycle, which is dominated by rain and snow fed lower order streams. It has low stream frequency (Fs) and moderate drainage density (Dd) of 2.69 km/km 2. Bifurcation ratios (Rb) of various stream orders indicate that streams up to 3rd order are surging through highly dissected mountainous terrain, which facilitates high overland flow and less recharge into the sub-surface resulting in low groundwater potential in the zones of 1st, 2nd, and 3rd order streams of the Suketi river basin. The circulatory ratio (Rc) of 0.65 and elongation ratio (Re) of 0.80 show elongated nature of the Suketi river basin, while infiltration number (If) of 10.66 indicates dominance of relief features and low groundwater potential in the high altitude mountainous terrain. The asymmetry factor (Af) of Suketi river basin indicates that the palaeo-tectonic tilting, at drainage basin scale, was towards the downstream right side of the

  2. Hellas basin, Mars: Formation by oblique impact

    NASA Technical Reports Server (NTRS)

    Leonard, Gregory J.; Tanaka, Kenneth L.

    1993-01-01

    Hellas, a 2,000-km-diameter, roughly circular multiring impact basin in the southern highlands of Mars, has a pronounced southeastern lobe of rim material that extends for some 1,500 km. This lobe and a system of ridges concentric to the southern part of the basin (including part of the lobe) were interpreted to be formed by an oblique impact that was inclined in the direction of the lobe. Our preliminary geologic mapping of the Hellas region (lat -20 to -65 deg, long 250 to 320 deg) at 1:5,000,000 scale gives this hypothesis additional supporting evidence, including a symmetric distribution of basin ejecta and volcanic centers across the inferred trend of the impact. Furthermore, measurements of relief indicate that the downrange ejecta may be about twice as thick as they are elsewhere around the rim.

  3. Configuration Management Plan for K Basins

    SciTech Connect

    Weir, W.R.; Laney, T.

    1995-01-27

    This plan describes a configuration management program for K Basins that establishes the systems, processes, and responsibilities necessary for implementation. The K Basins configuration management plan provides the methodology to establish, upgrade, reconstitute, and maintain the technical consistency among the requirements, physical configuration, and documentation. The technical consistency afforded by this plan ensures accurate technical information necessary to achieve the mission objectives that provide for the safe, economic, and environmentally sound management of K Basins and the stored material. The configuration management program architecture presented in this plan is based on the functional model established in the DOE Standard, DOE-STD-1073-93, {open_quotes}Guide for Operational Configuration Management Program{close_quotes}.

  4. Basin topology in dissipative chaotic scattering.

    PubMed

    Seoane, Jesús M; Aguirre, Jacobo; Sanjuán, Miguel A F; Lai, Ying-Cheng

    2006-06-01

    Chaotic scattering in open Hamiltonian systems under weak dissipation is not only of fundamental interest but also important for problems of current concern such as the advection and transport of inertial particles in fluid flows. Previous work using discrete maps demonstrated that nonhyperbolic chaotic scattering is structurally unstable in the sense that the algebraic decay of scattering particles immediately becomes exponential in the presence of weak dissipation. Here we extend the result to continuous-time Hamiltonian systems by using the Henon-Heiles system as a prototype model. More importantly, we go beyond to investigate the basin structure of scattering dynamics. A surprising finding is that, in the common case where multiple destinations exist for scattering trajectories, Wada basin boundaries are common and they appear to be structurally stable under weak dissipation, even when other characteristics of the nonhyperbolic scattering dynamics are not. We provide numerical evidence and a geometric theory for the structural stability of the complex basin topology.

  5. Mechanics of basin inversion: Finite element modelling of the Pannonian Basin System

    NASA Astrophysics Data System (ADS)

    Jarosinski, M.; Beekman, F.; Matenco, L.; Cloetingh, S.

    2011-04-01

    This finite element modelling study addresses the contraction of rheologically layered and laterally heterogeneous lithosphere representative for the Pannonian Basin and its surroundings. The time interval and strain rate adopted in the experiments reflect the Pliocene-Quaternary inversion of the basin. Several sets of fully coupled elastoviscoplastic thermo-mechanical, plane strain 2D models explore the evolution of buckling, and stress/strain changes across the lithosphere. The viscous rheology of the asthenosphere allows for a detailed simulation of isostatic rebound during deformation. The numerical models predict the successive development of surface undulations, caused by crustal and/or lithosphere folding, at three different characteristic wavelengths. Among these, the longest wavelength folds occur systematically at the rim of the basin as marginal bulges, while the short wavelength folds overprint the earlier folds and are observed at a later stage during compression. The thermo-mechanical evolution of the lithosphere in response to progressive horizontal contraction is described in terms of a characteristic delay of the changes in the stress regime and a reduction of elastic strain in the strong crustal layers. The models predict a change in stress state along the flanks of the basin, caused by the development of weak basin lithosphere in their vicinity. Comparing the modelling results with tectonic features of the Pannonian Basin has resulted in the identification of three different stages in the Pliocene-Quaternary basin inversion of the Pannonian-Carpathian system.

  6. Evolutionary mass-flow megaturbidites in interplate basin: example of the North Pyrenean basin

    SciTech Connect

    Bourrouilh, R.

    1986-05-01

    The Cretaceous North Pyrenean interplate basin develops in close relationship with the opening of the Bay of Biscay. The basin margins and its gravity sedimentary filling are related to differential movements of Iberian and European plates. Optimal climatic and morphologic conditions allow large amounts of carbonates to be deposited on its margins, major factors provoked the sedimentary and tectonic instability of the basin shelf and slope, particularly by reactivating a deep, ancient fault network. These events generated a single event or a series of successive autosuspended mass flows, which differentiate into megaturbidites, spreading over large areas of the basin floor. This large distribution of instantaneous evolutionary mass-flow megaturbidites, which pertain to the normal carbonate gravity sedimentation of the basin, allows us to determine: (1) paleoenvironments such as areas of paleoslopes; (2) the sedimentary and tectonic migration of the shelf break and of the basinal depocenter, and the relation of migration to regional plate tectonics; (3) evolution of local areas of special interest (petroleum geology), or evolution of the interplate basin, especially when it becomes a single trough (birth of first regional linear sequences); (4) interference of local centered transfer system (i.e., canyon fan or point slope fan) and regional linear transfer system (i.e., shelf break and slope).

  7. Ground Motion Prediction Atop Geometrically Complex Sedimentary Basins - The Dead Sea Basin

    NASA Astrophysics Data System (ADS)

    Shani-Kadmiel, S.; Tsesarsky, M.; Louie, J. N.; Gvirtzman, Z.

    2014-12-01

    The Dead Sea Transform (DST) is the source for some of the largest earthquakes in the eastern Mediterranean. Several deep and structurally complex sedimentary basins are associated with the DST. These basins are up to 10 km deep and typically bounded by active fault zones. The low seismicity of the DST combined with the limited instrumental coverage of the seismic network in the area result in a critical knowledge gap. Therefore, it is necessary to complement the limited instrumental data with synthetic data based on computational modeling, in order to study the effects of earthquake ground motion in these sedimentary basins. We performed a 2D ground-motion analysis in the Dead Sea Basin (DSB) using a finite-difference code. Results indicate a complex pattern of ground motion amplification affected by the geometric features in the basin. To distinguish between the individual contributions of each geometrical feature in the basin, we developed a semiquantitative decomposition approach. This approach enabled us to interpret the DSB results as follows: (1) Ground-motion amplification as a result of resonance occurs basin-wide due to a high impedance contrast at the base of the uppermost layer; (2) Steep faults generate a strong edge-effect that further ampli- fies ground motions; (3) Sub-basins cause geometrical focusing that may significantly amplify ground motions; and (4) Salt diapirs diverge seismic energy and cause a de- crease in ground-motion amplitude. We address the significance of ground motion amplification due to geometrical focusing via an analytical and numerical study. We show that effective geometrical focusing occurs for a narrow set of eccentricities and velocity ratios, where seismic energy is converged to a region of ±0.5 km from surface. This mechanism leads to significant ground motion amplification at the center of the basin, up to a factor of 3; frequencies of the modeled spectrum are amplified up to the corner frequency of the source.

  8. Sedimentation in Canada Basin, Western Arctic

    NASA Astrophysics Data System (ADS)

    Mosher, D. C.; Shimeld, J.; Jackson, R.; Hutchinson, D. R.; Chapman, B.; Chian, D.; Childs, J. R.; Mayer, L. A.; Edwards, B. D.; Verhoef, J.

    2010-12-01

    The Canada Basin of the western Arctic Ocean is the least studied ocean basin on Earth. Marine seismic field programs were conducted during the past 5 years in order to study the geology, sedimentary history and geomorphology of the region. As part of this program, five annual icebreaker expeditions acquired bathymetric, seismic reflection and seismic refraction data on a regional scale. More than 12,000 km of multi-channel seismic reflection data and 120 sonobuoy seismic refraction records over abyssal plain and continental rise regions of Canada Basin, Northwind Ridge and Alpha Ridge were acquired. The success of these programs was achieved through novel technical modifications to equipment to permit towing in heavy ice conditions and through collaboration between multiple Canadian and US agencies and institutions, enabling utilization of two ice breakers during seismic and multibeam data acquisition in heavy ice. The seafloor of the Canada Basin is remarkably flat-lying in its central region, with little bathymetric change over most of its extent. The sedimentary succession is generally flat lying with reflections extending over hundreds of km. These reflections onlap bathymetric highs, such as Alpha and Northwind ridges. The sedimentary succession is thickest in the Beaufort Sea region, reaching more than 6.5 km, and generally thins to the north and west. Reflection characteristics suggest that sediment volume input to the Arctic Ocean has been high and dominated by turbidity current deposition, similar to Amundsen and Nansen Basins of the eastern Arctic. These turbidites originate from the eastern and southern continental margins. There is no evidence of contemporaneous or post-depositional reworking by bottom currents. Additionally, there is little evidence of tectonic deformation after primary basin-forming events except in the NE quadrant, nearer Alpha Ridge. In this area, there is significant normal faulting propagating from basement through much of the

  9. Geothermal structure of Australia's east coast basins

    NASA Astrophysics Data System (ADS)

    Danis, C. R.; O'Neill, C.

    2010-12-01

    The east coast sedimentary basins of Australia formed on an active margin of eastern Gondwana, and constitute an important hydrocarbon resource. The 1600km long Sydney-Gunnedah-Bowen Basin (SGBB) is largest east coast basin system, with thick Permian to Jurassic sedimentary successions overlying Palaeozoic basement rocks. The SGBB has been the focus of renewed geothermal exploration interest, however, the thermal state and geothermal potential of the system is largely unconstrained. Geothermal exploration programs require an accurate estimate of subsurface temperature information, in addition to favourable geology, to make informed decisions on potential targe developments. Primarily temperature information comes from downhole measurements, generally non-equilibrated, which are traditionally extrapolated to depth, however such extrapolation does not take into account variations in geological structure or thermal conductivity. Here we import deep 3D geological models into finite element conduction simulations, using the code Underworld, to calculate the deep thermal structure of the basin system. Underworld allows us to incorporate complex, detailed geological architecture models, incorporating different material properties for different layers, with variable temperature and depth-dependent properties. We adopt a fixed top boundary temperature on a variable topographic surface, and vary the bottom surface boundary condition, to converge of models which satisfy equilibrated downhole temperature measurement constraints. We find coal plays an important role in insulating sedimentary basins. Heat refracts around the coal interval and produces elevated temperatures beneath thick sediments, especially where thick coal intervals are present. This workflow has been formalized into an Underworld geothermal model library, enabling model centric computational workflows. Using the imported model architecture from the geology, data can be continuously updated and added to the

  10. Tectonic history of the Illinois basin

    SciTech Connect

    Kolata, D.R.; Nelson, J.W. )

    1990-05-01

    The Illinois basin began as a failed rift that developed during breakup of a supercontinent approximately 550 Ma. A rift basin in the southernmost part of the present Illinois basin subsided rapidly and filled with about 3,000 m of probable Early and Middle Cambrian sediments. By the Late Cambrian, the rift-bounding faults became inactive and a broad relatively slowly subsiding embayment, extending well beyond the rift and open to the Iapetus Ocean, persisted through most of the Paleozoic Era. Widespread deformation swept through the proto-Illinois basin beginning in the latest Mississippian, continuing to the end of the Paleozoic Era. Uplift of basement fault blocks resulted in the formation of many major folds and faults. The timing of deformation and location of these structures in the forelands of the Ouachita and Alleghanian orogenic belts suggest that much of the deformation resulted from continental collision between North America and Gondwana. The associated compressional stress reactivated the ancient rift-bounding faults, upthrusting the northern edge of a crustal block approximately 1,000 m within the rift. Concurrently, dikes (radiometrically dated as Early Permian), sills, and explosion breccias formed in or adjacent to the reactivated rift. Subsequent extensional stress, probably associated with breakup of Pangea, caused the crustal block within the rift to sink back to near its original position. High-angle, northeast- to east-west-trending normal faults, with as much as 1,000 m of displacement, formed in the southern part of the basin. These faults displace some of the northwest trending Early Permian dikes. Structural closure of the southern end of the Illinois basin was caused by uplift of the Pascola arch sometime between the Late Pennsylvanian and Late Cretaceous.

  11. Paleohydrogeology of the San Joaquin basin, California

    USGS Publications Warehouse

    Wilson, A.M.; Garven, G.; Boles, J.R.

    1999-01-01

    Mass transport can have a significant effect on chemical diagenetic processes in sedimentary basins. This paper presents results from the first part of a study that was designed to explore the role of an evolving hydrodynamic system in driving mass transport and chemical diagenesis, using the San Joaquin basin of California as a field area. We use coupled hydrogeologic models to establish the paleohydrogeology, thermal history, and behavior of nonreactive solutes in the basin. These models rely on extensive geological information and account for variable-density fluid flow, heat transport, solute transport, tectonic uplift, sediment compaction, and clay dehydration. In our numerical simulations, tectonic uplift and ocean regression led to large-scale changes in fluid flow and composition by strengthening topography-driven fluid flow and allowing deep influx of fresh ground water in the San Joaquin basin. Sediment compaction due to rapid deposition created moderate overpressures, leading to upward flow from depth. The unusual distribution of salinity in the basin reflects influx of fresh ground water to depths of as much as 2 km and dilution of saline fluids by dehydration reactions at depths greater than ???2.5 km. Simulations projecting the future salinity of the basin show marine salinities persisting for more than 10 m.y. after ocean regression. Results also show a change from topography-to compaction-driven flow in the Stevens Sandstone at ca. 5 Ma that coincides with an observed change in the diagenetic sequence. Results of this investigation provide a framework for future hydrologic research exploring the link between fluid flow and diagenesis.

  12. Atlantic Mesozoic marginal basins: an Iberian view

    SciTech Connect

    Wilson, R.C.L.

    1987-05-01

    In the light of theoretical models for crustal stretching that precedes ocean opening, it is unlikely that Iberian basins have mirror image counterparts beneath North American or other European continental shelves. However, certain Iberian sedimentary sequences are comparable to those found in other basins. Of particular note are (1) the almost identical pre-rift sequences in all these areas, (2) the development of Upper Jurassic carbonate buildups in Portugal, Morocco, and beneath the Scotian Shelf, and (3) the hydrocarbon-bearing Upper Jurassic and Lower Cretaceous synrift and postrift siliciclastics of North America, Iberia, and Aquitaine. In the prerift sequences, Triassic red beds are capped by evaporites, which subsequently influenced the structural development of basins. Intertidal and supratidal carbonates occur at the base of the Jurassic and are overlain by Lower and Middle Jurassic limestone-shale sequences, which in places contain bituminous shales. In Portugal only, resedimented carbonates of Toarcian-Aalenian age are associated with an uplifted basement horst. In Portugal, Aquitaine, and eastern Canada, Middle Jurassic high-energy carbonate platforms developed. Synrift siliciclastic sequences show spectacular evidence for deposition within fault-bounded basins. In Portugal, lower Kimmeridgian clastics are up to 3 km thick, but Upper-Lower Cretaceous sequences are relatively thin (ca. 1 km), in contrast to those of the Basco-Cantabrian region where they exceed 10 km. In the latter region occurs the fluvially dominated Wealden (Upper Jurassic-Neocomian) and Urgonian carbonate platforms and associated basinal sediments. In the Asturias basin, Kimmeridgian shales and fluvially dominated deltaic sandstones succeed conglomeratic fluvial sandstones of uncertain age.

  13. Evolution of the San Jorge basin, Argentina

    SciTech Connect

    Fitzgerald, M.G. ); Uliana, M.A. ); Biddle, K.T. ); Mitchum, R.M. Jr.

    1990-06-01

    The San Jorge basin, although small, is the most important hydrocarbon-producing basin in Argentina. Remaining untested potential is high because of the presence of good source rock, favorable structural complexity, and multiple reservoirs. Reservoir quality is commonly low because of the highly tuffaceous sandstones. The sedimentary fill of the basin is closely related to its tectonic history. Northwest-southeast-trending grabens formed and filled during a Triassic and Early Jurassic early rift phase, climaxing with a pervasive Middle Jurassic volcanic episode; continued growth and filling of the basin occurred during a Late Jurassic-earliest Cretaceous late rift phase and Cretaceous early and late sag phases. Late Cretaceous-early Tertiary extension set up many of the present-day structural traps along normal faults. Middle Tertiary Andean compression produced the narrow, north-south San Bernardo structural belt, which exhibits reversed movement on older, normal, graben-bounding faults and on local, low-angle thrust faults. Marked early to middle Tertiary erosion produced a significant unconformity within Cretaceous beds around basin margins. Origin of Upper Jurassic and lowermost Cretaceous sedimentary fill is primarily lacustrine or fluvial in origin. Lacustrine, organic-rich black shales are fringed by oolitic and other limestones and fluvial-deltaic sandstones derived mostly from the north. A significant southern source of sand existed during the Valanginian. Interbedded marine shales occur mostly to the west toward a presumed marine seaway connection to the northern Magallanes basin. Middle to Upper Cretaceous sedimentary rocks, sourced mostly from the north, are mainly fluvial sandstone-shale successions with some minor lacustrine influence. Reservoir quality glauconitic sands were deposited during a Late Cretaceous-early Tertiary marine incursion from the Atlantic.

  14. Avian cholera in Nebraska's Rainwater Basin

    USGS Publications Warehouse

    Windingstad, R.M.; Hurt, J.J.; Trout, A.K.; Cary, J.

    1984-01-01

    The first report of avian cholera in North America occurred in northwestern Texas in winter 1944 (Quortrup et al. 1946). In 1975, mortality from avian cholera occurred for the first time in waterfowl in the Rainwater Basin of Nebraska when an estimated 25,000 birds died (Zinkl et al. 1977). Avian cholera has continued to cause mortality in wild birds in specific areas of the Basin each spring since. Losses of waterfowl from avian cholera continue to be much greater in some of the wetlands in the western part of the Basin than in the east. Several wetlands in the west have consistently higher mortality and are most often the wetlands where initial mortality is noticed each spring (Figure 1). The establishment of this disease in Nebraska is of considerable concern because of the importance of the Rainwater Basin as a spring staging area for waterfowl migrating to their breeding grounds. The wetlands in this area are on a major migration route used by an estimated 5 to 9 million ducks and several hundred thousand geese. A large portion of the western mid-continental greater white-fronted goose (Anser albifrons) population stage in the Basin each spring. Occasionally, whooping cranes (Grus americana) use these wetlands during migration, and lesser sandhill cranes (Grus canadensis) staging on the nearby Platte River sometimes use wetlands where avian cholera occurs (Anonymous 1981). Our objectives were to determine whether certain water quality variables in the Rainwater Basin differed between areas of high and low avian cholera incidence. These results would then be used for laboratory studies involving the survivability of Pasteurella multocida, the causative bacterium of avian cholera. Those studies will be reported elsewhere.

  15. The "normal" elongation of river basins

    NASA Astrophysics Data System (ADS)

    Castelltort, Sebastien

    2013-04-01

    The spacing between major transverse rivers at the front of Earth's linear mountain belts consistently scales with about half of the mountain half-width [1], despite strong differences in climate and rock uplift rates. Like other empirical measures describing drainage network geometry this result seems to indicate that the form of river basins, among other properties of landscapes, is invariant. Paradoxically, in many current landscape evolution models, the patterns of drainage network organization, as seen for example in drainage density and channel spacing, seem to depend on both climate [2-4] and tectonics [5]. Hovius' observation [1] is one of several unexplained "laws" in geomorphology that still sheds mystery on how water, and rivers in particular, shape the Earth's landscapes. This narrow range of drainage network shapes found in the Earth's orogens is classicaly regarded as an optimal catchment geometry that embodies a "most probable state" in the uplift-erosion system of a linear mountain belt. River basins currently having an aspect away from this geometry are usually considered unstable and expected to re-equilibrate over geological time-scales. Here I show that the Length/Width~2 aspect ratio of drainage basins in linear mountain belts is the natural expectation of sampling a uniform or normal distribution of basin shapes, and bears no information on the geomorphic processes responsible for landscape development. This finding also applies to Hack's [6] law of river basins areas and lengths, a close parent of Hovius' law. [1]Hovius, N. Basin Res. 8, 29-44 (1996) [2]Simpson, G. & Schlunegger, F. J. Geophys. Res. 108, 2300 (2003) [3]Tucker, G. & Bras, R. Water Resour. Res. 34, 2751-2764 (1998) [4]Tucker, G. & Slingerland, R. Water Resour. Res. 33, 2031-2047 (1997) [5]Tucker, G. E. & Whipple, K. X. J. Geophys. Res. 107, 1-1 (2002) [6]Hack, J. US Geol. Surv. Prof. Pap. 294-B (1957)

  16. View westsouthwest of marine railway at reserve basin of Philadelphia ...

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

    View west-southwest of marine railway at reserve basin of Philadelphia Naval Shipyard. - Naval Base Philadelphia-Philadelphia Naval Shipyard, Reserve Basin & Marine Railway, League Island, Philadelphia, Philadelphia County, PA

  17. 17. VIEW OF SETTLING BASIN, SHOWING FLUME TRACK SPUR CROSSING ...

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

    17. VIEW OF SETTLING BASIN, SHOWING FLUME TRACK SPUR CROSSING OVER SETTLING BASIN, SPARE BENT MATERIAL IN RIGHT-HAND FOREGROUND, BYPASS FLUME, AND SHACK #6 IN BACKGROUND, LOOKING NORTHWEST - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  18. 14. INSIDE VIEW OF FLUME, LOOKING DOWNSTREAM TOWARD SETTLING BASIN, ...

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

    14. INSIDE VIEW OF FLUME, LOOKING DOWNSTREAM TOWARD SETTLING BASIN, SHOWING RIGHT FORK TO BYPASS, LEFT FORK TO BASIN - Electron Hydroelectric Project, Along Puyallup River, Electron, Pierce County, WA

  19. Grande Ronde Basin Fish Habitat Enhancement Project : 1998 Annual Report.

    SciTech Connect

    McGowan, Vance R.; Powell, Russ M.

    1999-05-01

    The primary goal of ''The Grande Ronde Basin Fish Habitat Improvement Project'' is to access, create, improve, protect, and restore reparian and instream habitat for anadromous salmonids, thereby maximizing opportunities for natural fish production within the basin.

  20. View west of reserve basin of submarine trout and frigate ...

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

    View west of reserve basin of submarine trout and frigate Edward E. McDonnell - Naval Base Philadelphia-Philadelphia Naval Shipyard, Reserve Basin & Marine Railway, League Island, Philadelphia, Philadelphia County, PA

  1. Hazard categorization of 105-KE basin debris removal project

    SciTech Connect

    Meichle, R.H.

    1996-01-25

    This supporting document provides the hazard categorization for 105-KE Basin Debris Removal Project activities planned in the K east Basin. All activities are categorized as less than Hazard Category 3.

  2. Geology of the Caloris basin, Mercury: a view from MESSENGER.

    PubMed

    Murchie, Scott L; Watters, Thomas R; Robinson, Mark S; Head, James W; Strom, Robert G; Chapman, Clark R; Solomon, Sean C; McClintock, William E; Prockter, Louise M; Domingue, Deborah L; Blewett, David T

    2008-07-04

    The Caloris basin, the youngest known large impact basin on Mercury, is revealed in MESSENGER images to be modified by volcanism and deformation in a manner distinct from that of lunar impact basins. The morphology and spatial distribution of basin materials themselves closely match lunar counterparts. Evidence for a volcanic origin of the basin's interior plains includes embayed craters on the basin floor and diffuse deposits surrounding rimless depressions interpreted to be of pyroclastic origin. Unlike lunar maria, the volcanic plains in Caloris are higher in albedo than surrounding basin materials and lack spectral evidence for ferrous iron-bearing silicates. Tectonic landforms, contractional wrinkle ridges and extensional troughs, have distributions and age relations different from their counterparts in and around lunar basins, indicating a different stress history.

  3. Old Basin Filled by Smooth Plains

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Old basin, 190 km in diameter, filled by smooth plains at 43 degrees S, 55 degrees W. The basin's hummocky rim is partly degraded and cratered by later events. Mariner 10 frame 166607.

    The Mariner 10 mission, managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, explored Venus in February 1974 on the way to three encounters with Mercury-in March and September 1974 and in March 1975. The spacecraft took more than 7,000 photos of Mercury, Venus, the Earth and the Moon.

    Image Credit: NASA/JPL/Northwestern University

  4. Isidis Basin, Mars: Geology and Topography

    NASA Astrophysics Data System (ADS)

    Hiesinger, H.; Head, J. W., III

    2003-04-01

    Building on Bridges et al. [2003, JGR 108], we are currently studying the general geologic history and evolution of the Isidis basin based on topographic and imaging data obtained by orbiting spacecraft such as Mars Global Surveyor (MGS) and Mars Odyssey. This study complements our recently completed analyses on Syrtis Major to the west [Hiesinger and Head, 2002, LPSC 1063] and the transition between Syrtis Major and Isidis [Ivanov and Head, 2002, LPSC 1341]. We are interested in a number of scientific questions, for example, what are the characteristics of the Isidis rim and what caused its present morphology? What is the role and fate of volatiles in the Isidis basin and what are the characteristics of the uppermost surface layer? Does the floor of the Isidis basin primarily consist of volcanic plains as indicated by wrinkle ridges and cone-like features, material deposited by a catastrophic collapse of the rim as proposed by Tanaka et al. [2000, GRL 29], or of sediments deposited in an ocean as suggested by Parker et al. [1989, Icarus 82]? What is the stratigraphy of the deposits within the Isidis basin and what processes were responsible for its present appearance? For our study we used MOLA topography data with a spatial resolution of 128 pixel/deg. The data allowed us to obtain a detailed view of the Isidis basin, its structure, stratigraphy, geologic history and its evolution. Our preliminary investigation let us conclude that (1) the basin floor is tilted towards the southwest with about 0.015 degree, (2) there are 2 types of ridges within the Isidis basin, (3) ridges of the thumbprint terrain are ~10-50 m high, less than ~5-7 km wide, and occur at narrowly constrained elevations of ~-3600 to -3700 m, (4) these ridges occur only within the innermost ring structure and most of them are not exposed at the lowest elevations, (5) wrinkle ridges are ~75-100 m high, less than ~70 km wide, hundreds of kilometers long and occur over a wide range of elevations, (6

  5. Atlas of major Appalachian basin gas plays

    SciTech Connect

    Aminian, K.; Avary, K.L.; Baranoski, M.T.; Flaherty, K.; Humphreys, M.; Smosna, R.A.

    1995-06-01

    This regional study of gas reservoirs in the Appalachian basin has four main objectives: to organize all of the -as reservoirs in the Appalachian basin into unique plays based on common age, lithology, trap type and other geologic similarities; to write, illustrate and publish an atlas of major gas plays; to prepare and submit a digital data base of geologic, engineering and reservoir parameters for each gas field; and technology transfer to the oil and gas industry during the preparation of the atlas and data base.

  6. A global distributed basin morphometric dataset.

    PubMed

    Shen, Xinyi; Anagnostou, Emmanouil N; Mei, Yiwen; Hong, Yang

    2017-01-05

    Basin morphometry is vital information for relating storms to hydrologic hazards, such as landslides and floods. In this paper we present the first comprehensive global dataset of distributed basin morphometry at 30 arc seconds resolution. The dataset includes nine prime morphometric variables; in addition we present formulas for generating twenty-one additional morphometric variables based on combination of the prime variables. The dataset can aid different applications including studies of land-atmosphere interaction, and modelling of floods and droughts for sustainable water management. The validity of the dataset has been consolidated by successfully repeating the Hack's law.

  7. A global distributed basin morphometric dataset

    NASA Astrophysics Data System (ADS)

    Shen, Xinyi; Anagnostou, Emmanouil N.; Mei, Yiwen; Hong, Yang

    2017-01-01

    Basin morphometry is vital information for relating storms to hydrologic hazards, such as landslides and floods. In this paper we present the first comprehensive global dataset of distributed basin morphometry at 30 arc seconds resolution. The dataset includes nine prime morphometric variables; in addition we present formulas for generating twenty-one additional morphometric variables based on combination of the prime variables. The dataset can aid different applications including studies of land-atmosphere interaction, and modelling of floods and droughts for sustainable water management. The validity of the dataset has been consolidated by successfully repeating the Hack's law.

  8. A global distributed basin morphometric dataset

    PubMed Central

    Shen, Xinyi; Anagnostou, Emmanouil N.; Mei, Yiwen; Hong, Yang

    2017-01-01

    Basin morphometry is vital information for relating storms to hydrologic hazards, such as landslides and floods. In this paper we present the first comprehensive global dataset of distributed basin morphometry at 30 arc seconds resolution. The dataset includes nine prime morphometric variables; in addition we present formulas for generating twenty-one additional morphometric variables based on combination of the prime variables. The dataset can aid different applications including studies of land-atmosphere interaction, and modelling of floods and droughts for sustainable water management. The validity of the dataset has been consolidated by successfully repeating the Hack’s law. PMID:28055032

  9. Megafans of the Northern Kalahari Basin

    NASA Technical Reports Server (NTRS)

    Wilkinson, M. J.; Miller, R. McG.; Eckardt, F.; Kreslavsky, M. A.

    2016-01-01

    We identify eleven megafans (partial cones of fluvial sediment, >80 km radius) in the northern Kalahari Basin, using several criteria based on VIS and IR remotely sensed data and SRTM-based surface morphology reconstructions. Two other features meet fewer criteria of the form which we class as possible megafans. The northern Kalahari megafans are located in a 1700 km arc around the southern and eastern flanks of the Angola's Bié Plateau, from northern Namibia through northwest Botswana to western Zambia. Three lie in the Owambo subbasin centered on the Etosha Pan, three in the relatively small Okavango rift depression, and five in the Upper Zambezi basin. The population includes the well-known Okavango megafan (150 km), Namibia's Cubango megafan, the largest megafan in the region (350 km long), and the largest nested group (the five major contiguous megafans on the west slopes of the upper Zambezi Valley). We use new, SRTM-based topographic roughness data to discriminate various depositional surfaces within the flat N. Kalahari landscapes. We introduce the concepts of divide megafans, derived megafans, and fan-margin rivers. Conclusions. (i) Eleven megafan cones total an area of 190,000 sq km. (ii) Different controls on megafan size operate in the three component basins: in the Okavango rift structural controls become the prime constraint on megafan length by controlling basin dimensions. Megafans in the other les constricted basins appear to conform to classic relationships fan area, slope, and feeder-basin area. (iii) Active fans occupy the Okavango rift depression with one in the Owambo basin. The rest of the population are relict but recently active fans (surfaces are relict with respect to activity by the feeder river). (iv) Avulsive behavior of the formative river-axiomatic for the evolution of megafans-has resulted in repeated rearrangements of regional drainage, with likely effects in the study area well back into the Neogene. Divide megafans comprise the

  10. Tectonic differences between eastern and western sub-basins of the Qiongdongnan Basin and their dynamics

    NASA Astrophysics Data System (ADS)

    Liu, Jianbao; Sun, Zhen; Wang, Zhenfeng; Sun, Zhipeng; Zhao, Zhongxian; Wang, Zhangwen; Zhang, Cuimei; Qiu, Ning; Zhang, Jiangyang

    2015-03-01

    The central depression of the Qiongdongnan Basin can be divided into the eastern and western sub-basins by the Lingshui-Songnan paleo-uplift. To the northwest, the orientation of the faults turns from NE, to EW, and later to NW; In the southwest, the orientation of the faults turns from NE, to NNE, and then to NW, making the central depression much wider towards the west. In the eastern sub-basin, the NE-striking faults and the EW-striking faults made up an echelon, making the central depression turn wider towards the east. Fault activity rates indicate that faulting spreads gradually from both the east and west sides to the middle of the basin. Hence, extensional stress in the eastern sub-basin may be related to the South China Sea spreading system, whereas the western sub-basin was more under the effect of the activity of the Red River Fault. The extreme crustal stretching in the eastern sub-basin was probably related to magmatic setting. It seems that there are three periods of magmatic events that occurred in the eastern sub-basin. In the eastern part of the southern depression, the deformed strata indicate that the magma may have intruded into the strata along faults around T60 (23.3 Ma). The second magmatic event occurred earlier than 10.5 Ma, which induced the accelerated subsidence. The final magmatic event commenced later than 10 Ma, which led to today's high heat flow. As for the western sub-basin, the crust thickened southward, and there seemed to be a southeastward lower crustal flow, which happened during continental breakup which was possibly superimposed by a later lower crustal flow induced by the isostatic compensation of massive sedimentation caused by the right lateral slipping of the Red River Fault. Under the huge thick sediment, super pressure developed in the western sub-basin. In summary, the eastern sub-basin was mainly affected by the South China Sea spreading system and a magma setting, whereas the western sub-basin had a closer

  11. SimBasin: serious gaming for integrated decision-making in the Magdalena-Cauca basin

    NASA Astrophysics Data System (ADS)

    Craven, Joanne; Angarita, Hector; Corzo, Gerald

    2016-04-01

    The Magdalena-Cauca macrobasin covers 24% of the land area of Colombia, and provides more than half of the country's economic potential. The basin is also home a large proportion of Colombia's biodiversity. These conflicting demands have led to problems in the basin, including a dramatic fall in fish populations, additional flooding (such as the severe nationwide floods caused by the La Niña phenomenon in 2011), and habitat loss. It is generally believed that the solution to these conflicts is to manage the basin in a more integrated way, and bridge the gaps between decision-makers in different sectors and scientists. To this end, inter-ministerial agreements are being formulated and a decision support system is being developed by The Nature Conservancy Colombia. To engage stakeholders in this process SimBasin, a "serious game", has been developed. It is intended to act as a catalyst for bringing stakeholders together, an illustration of the uncertainties, relationships and feedbacks in the basin, and an accessible introduction to modelling and decision support for non-experts. During the game, groups of participants are led through a 30 year future development of the basin, during which they take decisions about the development of the basin and see the impacts on four different sectors: agriculture, hydropower, flood risk, and environment. These impacts are displayed through seven indicators, which players should try to maintain above critical thresholds. To communicate the effects of uncertainty and climate variability, players see the actual value of the indicator and also a band of possible values, so they can see if their decisions have actually reduced risk or if they just "got lucky". The game works as a layer on top of a WEAP water resources model of the basin, adapted from a basin-wide model already created, so the fictional game basin is conceptually similar to the Magdalena-Cauca basin. The game is freely available online, and new applications are being

  12. A new survey of multiring impact basins on Mars

    SciTech Connect

    Schultz, R.A.; Frey, H.V. )

    1990-08-30

    Multiring impact basins have profoundly influenced the geologic evolution of Mars. The authors compile and summarize the evidence for Martian impact basins and suggest eight new examples. Multiring basins on Mars define three morphologic subclasses with increasing basin size. Basins having diameters 300 < D < 1,850 km are morphologically comparable to the classic lunar Orientale basin. Argyre type basins (1,850 < D < 3,600 km) are characterized by a rugged annulus and concentric grabens. The largest, Chryse type basins (D > 3,600 km) have extremely shallow topographic profiles and numerous concentric structures expressed as scarps, massifs, and channels. Radial and concentric structures analogous to those associated with Orientale are not apparent for basins of Argyre size or larger. These variations in basin morphology and structure may be associated with mechanical interactions between basin-forming impacts, relatively thin, weak lithosphere, and, for the largest impacts, spherical target geometry. Multiring basins are recognized on all parts of Mars, including Tharsis, Elysium, and the northern lowlands. Much of the subsequent resurfacing of cratered terrain such as Lunae Planum ridged plains is associated spatially with multiring basins. Nucleation of long-lived volcanic complexes in Tharsis and Elysium was probably aided by early impact basins. The planetary terrain dichotomy was probably established during the period of heavy meteoritic bombardment, and subsequent processes in the northern plains region were not sufficiently vigorous to destroy or completely obscure the underlying multiring basin fabric. The revised population of multiring basins is consistent with the size frequency distribution of craters < 500 km in diameter on Mars.

  13. Hydrology of the Johnson Creek Basin, Oregon

    USGS Publications Warehouse

    Lee, Karl K.; Snyder, Daniel T.

    2009-01-01

    The Johnson Creek basin is an important resource in the Portland, Oregon, metropolitan area. Johnson Creek forms a wildlife and recreational corridor through densely populated areas of the cities of Milwaukie, Portland, and Gresham, and rural and agricultural areas of Multnomah and Clackamas Counties. The basin has changed as a result of agricultural and urban development, stream channelization, and construction of roads, drains, and other features characteristic of human occupation. Flooding of Johnson Creek is a concern for the public and for water management officials. The interaction of the groundwater and surface-water systems in the Johnson Creek basin also is important. The occurrence of flooding from high groundwater discharge and from a rising water table prompted this study. As the Portland metropolitan area continues to grow, human-induced effects on streams in the Johnson Creek basin will continue. This report provides information on the groundwater and surface-water systems over a range of hydrologic conditions, as well as the interaction these of systems, and will aid in management of water resources in the area. High and low flows of Crystal Springs Creek, a tributary to Johnson Creek, were explained by streamflow and groundwater levels collected for this study, and results from previous studies. High flows of Crystal Springs Creek began in summer 1996, and did not diminish until 2000. Low streamflow of Crystal Springs Creek occurred in 2005. Flow of Crystal Springs Creek related to water-level fluctuations in a nearby well, enabling prediction of streamflow based on groundwater level. Holgate Lake is an ephemeral lake in Southeast Portland that has inundated residential areas several times since the 1940s. The water-surface elevation of the lake closely tracked the elevation of the water table in a nearby well, indicating that the occurrence of the lake is an expression of the water table. Antecedent conditions of the groundwater level and autumn

  14. Procedures for ensuring community involvement in multijurisdictional river basins: a comparison of the Murray-Darling and Mekong river basins.

    PubMed

    Chenoweth, Jonathan L; Ewing, Sarah A; Bird, Juliet F

    2002-04-01

    Community involvement is fundamental to the management of multijurisdictional river basins but, in practice, is very difficult to achieve. The Murray-Darling basin, in Australia, and the Mekong River basin in Southeast Asia are both cooperatively managed multijurisdictional river basins where the management authorities have expressed an aim of community involvement. In the Murray-Darling basin vigorous efforts have promoted a culture of community consultation throughout each of the state jurisdictions involved, although true participation has not necessarily been achieved. In the Mekong basin the community is much more diverse and the successes so far have been largely at the local level, involving action in subsections of the basin. These case studies suggest that community involvement in the form of community consultation across large multijurisdictional river basins is achievable, but more comprehensive participation is not necessarily possible.

  15. 78 FR 23784 - Colorado River Basin Salinity Control Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-22

    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Colorado River Basin Salinity Control Advisory Council (Council) was established by the Colorado River Basin Salinity Control Act of 1974...

  16. 75 FR 25877 - Colorado River Basin Salinity Control Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-10

    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Colorado River Basin Salinity Control Advisory Council (Council) was established by the Colorado River Basin Salinity Control ] Act of 1974...

  17. 75 FR 66389 - Colorado River Basin Salinity Control Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-28

    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. SUMMARY: The Colorado River Basin Salinity Control Advisory Council (Council) was established by the Colorado River Basin Salinity Control Act of 1974 (Pub....

  18. 76 FR 61382 - Colorado River Basin Salinity Control Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-04

    ... Bureau of Reclamation Colorado River Basin Salinity Control Advisory Council AGENCY: Bureau of Reclamation, Interior. ACTION: Notice of public meeting. ] SUMMARY: The Colorado River Basin Salinity Control Advisory Council (Council) was established by the Colorado River Basin Salinity Control Act of 1974 (Pub....

  19. 77 FR 23508 - Colorado River Basin Salinity Control Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-19