Study on the Effect of Diamond Grain Size on Wear of Polycrystalline Diamond Compact Cutter

NASA Astrophysics Data System (ADS)

Abdul-Rani, A. M.; Che Sidid, Adib Akmal Bin; Adzis, Azri Hamim Ab

2018-03-01

Drilling operation is one of the most crucial step in oil and gas industry as it proves the availability of oil and gas under the ground. Polycrystalline Diamond Compact (PDC) bit is a type of bit which is gaining popularity due to its high Rate of Penetration (ROP). However, PDC bit can easily wear off especially when drilling hard rock. The purpose of this study is to identify the relationship between the grain sizes of the diamond and wear rate of the PDC cutter using simulation-based study with FEA software (ABAQUS). The wear rates of a PDC cutter with a different diamond grain sizes were calculated from simulated cuttings of cutters against granite. The result of this study shows that the smaller the diamond grain size, the higher the wear resistivity of PDC cutter.

Experimental Study on Longmaxi Shale Breaking Mechanism with Micro-PDC Bit

NASA Astrophysics Data System (ADS)

Wang, Teng; Xiao, Xiaohua; Zhu, Haiyan; Zhao, Jingying; Li, Yuheng; Lu, Ming

2017-10-01

China has abundant shale gas resource, but its geological conditions are complicated. This work sought to find the shale breaking mechanism with the polycrystalline diamond compact (PDC) bit when drilling the shale that is rich in stratification. Therefore, a laboratory-scale drilling device based on a drilling machine is developed. The influences of Longmaxi shale stratification on drilling parameters in the drilling process with micro-PDC bit are investigated. Six groups of drilling experiments with six inclination angles ( β = 0°, 15°, 30°, 45°, 60° and 90°), total thirty-six groups, are carried out. The weight on bit reaches the maximum value at β = 30° and reaches the minimum value at β = 0°. The biggest torque value is at β = 30°, and the smaller torque values are at β = 15°, β = 45° and β = 60°. When the inclination angle is between 30° and 60°, the shale fragmentation volume is larger. The inclination angle β = 0° is beneficial, and β = 15° and β = 60° are detrimental to controlling the drilling direction in the Longmaxi shale gas formation.

PDC bits break ground with advanced vibration mitigation

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

NONE

1995-10-01

Advancements in PDC bit technology have resulted in the identification and characterization of different types of vibrational modes that historically have limited PDC bit performance. As a result, concepts have been developed that prevent the initiation of vibration and also mitigate its damaging effects once it occurs. This vibration-reducing concept ensures more efficient use of the energy available to a PDC bit performance. As a result, concepts have been developed that prevent the imitation of vibration and also mitigate its damaging effects once it occurs. This vibration-reducing concept ensures more efficient use of the energy available to a PDC bit,more » thereby improving its performance. This improved understanding of the complex forces affecting bit performance is driving bit customization for specific drilling programs.« less

New PDC cutters improve drilling efficiency

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

Mensa-Wilmot, G.

1997-10-27

New polycrystalline diamond compact (PDC) cutters increase penetration rates and cumulative footage through improved abrasion, impact, interface strength, thermal stability, and fatigue characteristics. Studies of formation characterization, vibration analysis, hydraulic layouts, and bit selection continue to improve and expand PDC bit applications. The paper discusses development philosophy, performance characteristics and requirements, Types A, B, and C cutters, and combinations.

Drilling plastic formations using highly polished PDC cutters

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

Smith, R.H.; Lund, J.B.; Anderson, M.

1995-12-31

Highly plastic and over-pressured formations are troublesome for both roller cone and PDC bits. Thus far, attempts to increase penetration rates in these formations have centered around re-designing the bit or modifying the cutting structure. These efforts have produced only moderate improvements. This paper presents both laboratory and field data to illustrate the benefits of applying a mirror polished surface to the face of PDC cutters in drilling stressed formations. These cutters are similar to traditional PDC cutters, with the exception of the reflective mirror finish, applied to the diamond table surfaces prior to their installation in the bit. Resultsmore » of tests conducted in a single point cutter apparatus and a full-scale drilling simulator will be presented and discussed. Field results will be presented that demonstrate the effectiveness of polished cutters, in both water and oil-based muds. Increases in penetration rates of 300-400% have been observed in the Wilcox formation and other highly pressured shales. Typically, the beneficial effects of polished cutters have been realized at depths greater than 7000 ft, and with mud weights exceeding 12 ppg.« less

Results of NanTroSEIZE Expeditions Stages 1 & 2: Deep-sea Coring Operations on-board the Deep-sea Drilling Vessel Chikyu and Development of Coring Equipment for Stage 3

NASA Astrophysics Data System (ADS)

Shinmoto, Y.; Wada, K.; Miyazaki, E.; Sanada, Y.; Sawada, I.; Yamao, M.

2010-12-01

The Nankai-Trough Seismogenic Zone Experiment (NanTroSEIZE) has carried out several drilling expeditions in the Kumano Basin off the Kii-Peninsula of Japan with the deep-sea scientific drilling vessel Chikyu. Core sampling runs were carried out during the expeditions using an advanced multiple wireline coring system which can continuously core into sections of undersea formations. The core recovery rate with the Rotary Core Barrel (RCB) system was rather low as compared with other methods such as the Hydraulic Piston Coring System (HPCS) and Extended Shoe Coring System (ESCS). Drilling conditions such as hole collapse and sea conditions such as high ship-heave motions need to be analyzed along with differences in lithology, formation hardness, water depth and coring depth in order to develop coring tools, such as the core barrel or core bit, that will yield the highest core recovery and quality. The core bit is especially important in good recovery of high quality cores, however, the PDC cutters were severely damaged during the NanTroSEIZE Stages 1 & 2 expeditions due to severe drilling conditions. In the Stage 1 (riserless coring) the average core recovery was rather low at 38 % with the RCB and many difficulties such as borehole collapse, stick-slip and stuck pipe occurred, causing the damage of several of the PDC cutters. In Stage 2, a new design for the core bit was deployed and core recovery was improved at 67 % for the riserless system and 85 % with the riser. However, due to harsh drilling conditions, the PDC core bit and all of the PDC cutters were completely worn down. Another original core bit was also deployed, however, core recovery performance was low even for plate boundary core samples. This study aims to identify the influence of the RCB system specifically on the recovery rates at each of the holes drilled in the NanTroSEIZE coring expeditions. The drilling parameters such as weight-on-bit, torque, rotary speed and flow rate, etc., were analyzed and conditions such as formation, tools, and sea conditions which directly affect core recovery have been categorized. Also discussed will be the further development of such coring equipment as the core bit and core barrel for the NanTroSEIZE Stage 3 expeditions, which aim to reach a depth of 7000 m-below the sea floor into harder formations under extreme drilling conditions.

The study of microstructure of wear-resistant coatings applied for protection from abrasive wear of horizontal and tilt drilling drill bits

NASA Astrophysics Data System (ADS)

Markova, I. Yu; Zakharova, E. S.; Maslov, A. L.; Polushin, N. I.; Laptev, A. I.; SOvchinnikova, M.

2017-05-01

Drill bits of the cutting type over the period of their existence have undergone significant changes - from the use of carbide cutters to diamond composite PDC elements, in which the diamond layer is applied to a hardmetal substrate. Using such elements, it was possible to significantly increase the service life of the drill bits, however, during work, there is a significant abrasive deterioration of the bit body, which does not fully realize the advantages of PDC elements. Therefore, to protect the body from wear use special wear-resistant coatings. This work is devoted to research of microstructural coatings, namely coatings brands WokaDur NiA, HR-6750, HR-6750 with sublayer Rock Dur 47 on various steel substrates which applied by the gas-thermal spraying in Ltd “Oerlikon Metko Rus”. They were examined with the use of scanning electron microscopy, X-ray phase analysis and a Vickers micro-hardness tester. It was established that the microhardness of the coating matrix is 590-660 HV, and the microhardness of tungsten carbide particles reinforcing the coating, is 2145-2455 HV.

Numerical simulation study on the optimization design of the crown shape of PDC drill bit.

PubMed

Ju, Pei; Wang, Zhenquan; Zhai, Yinghu; Su, Dongyu; Zhang, Yunchi; Cao, Zhaohui

The design of bit crown is an important part of polycrystalline diamond compact (PDC) bit design, although predecessors have done a lot of researches on the design principles of PDC bit crown, the study of the law about rock-breaking energy consumption according to different bit crown shape is not very systematic, and the mathematical model of design is over-simplified. In order to analyze the relation between rock-breaking energy consumption and bit crown shape quantificationally, the paper puts forward an idea to take "per revolution-specific rock-breaking work" as objective function, and analyzes the relationship between rock properties, inner cone angle, outer cone arc radius, and per revolution-specific rock-breaking work by means of explicit dynamic finite element method. Results show that the change law between per revolution-specific rock-breaking work and the radius of gyration is similar for rocks with different properties, it is beneficial to decrease rock-breaking energy consumption by decreasing inner cone angle or outer cone arc radius. Of course, we should also consider hydraulic structure and processing technology in the optimization design of PDC bit crown.

Morphology of powders of tungsten carbide used in wear-resistant coatings and deposition on the PDC drill bits

NASA Astrophysics Data System (ADS)

Zakharova, E. S.; Markova, I. Yu; Maslov, A. L.; Polushin, N. I.; Laptev, A. I.

2017-05-01

Modern drill bits have high abrasive wear in the area of contact with the rock and removed sludge. Currently, these bits have a protective layer on the bit body, which consists of a metal matrix with inclusions of carbide particles. The research matrix of this coating and the wear-resistant particles is a prerequisite in the design and production of drill bits. In this work, complex investigation was made for various carbide powders of the grades Relit (tungsten carbide produced by Ltd “ROSNAMIS”) which are used as wear-resistant particles in the coating of the drill bit body. The morphology and phase composition of the chosen powders as well as the influence of a particle shape on prospects of their application in wear-resistance coating presented in this work.

Smaller Footprint Drilling System for Deep and Hard Rock Environments; Feasibility of Ultra-High-Speed Diamond Drilling

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

TerraTek, A Schlumberger Company

2008-12-31

The two phase program addresses long-term developments in deep well and hard rock drilling. TerraTek believes that significant improvements in drilling deep hard rock will be obtained by applying ultra-high rotational speeds (greater than 10,000 rpm). The work includes a feasibility of concept research effort aimed at development that will ultimately result in the ability to reliably drill 'faster and deeper' possibly with smaller, more mobile rigs. The principle focus is on demonstration testing of diamond bits rotating at speeds in excess of 10,000 rpm to achieve high rate of penetration (ROP) rock cutting with substantially lower inputs of energymore » and loads. The significance of the 'ultra-high rotary speed drilling system' is the ability to drill into rock at very low weights on bit and possibly lower energy levels. The drilling and coring industry today does not practice this technology. The highest rotary speed systems in oil field and mining drilling and coring today run less than 10,000 rpm - usually well below 5,000 rpm. This document provides the progress through two phases of the program entitled 'Smaller Footprint Drilling System for Deep and Hard Rock Environments: Feasibility of Ultra-High-Speed Diamond Drilling' for the period starting 30 June 2003 and concluding 31 March 2009. The accomplishments of Phases 1 and 2 are summarized as follows: (1) TerraTek reviewed applicable literature and documentation and convened a project kick-off meeting with Industry Advisors in attendance (see Black and Judzis); (2) TerraTek designed and planned Phase I bench scale experiments (See Black and Judzis). Improvements were made to the loading mechanism and the rotational speed monitoring instrumentation. New drill bit designs were developed to provided a more consistent product with consistent performance. A test matrix for the final core bit testing program was completed; (3) TerraTek concluded small-scale cutting performance tests; (4) Analysis of Phase 1 data indicated that there is decreased specific energy as the rotational speed increases; (5) Technology transfer, as part of Phase 1, was accomplished with technical presentations to the industry (see Judzis, Boucher, McCammon, and Black); (6) TerraTek prepared a design concept for the high speed drilling test stand, which was planned around the proposed high speed mud motor concept. Alternative drives for the test stand were explored; a high speed hydraulic motor concept was finally used; (7) The high speed system was modified to accommodate larger drill bits than originally planned; (8) Prototype mud turbine motors and the high speed test stand were used to drive the drill bits at high speed; (9) Three different rock types were used during the testing: Sierra White granite, Crab Orchard sandstone, and Colton sandstone. The drill bits used included diamond impregnated bits, a polycrystalline diamond compact (PDC) bit, a thermally stable PDC (TSP) bit, and a hybrid TSP and natural diamond bit; and (10) The drill bits were run at rotary speeds up to 5500 rpm and weight on bit (WOB) to 8000 lbf. During Phase 2, the ROP as measured in depth of cut per bit revolution generally increased with increased WOB. The performance was mixed with increased rotary speed, with the depth cut with the impregnated drill bit generally increasing and the TSP and hybrid TSP drill bits generally decreasing. The ROP in ft/hr generally increased with all bits with increased WOB and rotary speed. The mechanical specific energy generally improved (decreased) with increased WOB and was mixed with increased rotary speed.« less

Geometry and material choices govern hard-rock drilling performance of PDC drag cutters.

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

Wise, Jack LeRoy

2005-06-01

Sandia National Laboratories has partnered with industry on a multifaceted, baseline experimental study that supports the development of improved drag cutters for advanced drill bits. Different nonstandard cutter lots were produced and subjected to laboratory tests that evaluated the influence of selected design and processing parameters on cutter loads, wear, and durability pertinent to the penetration of hard rock with mechanical properties representative of formations encountered in geothermal or deep oil/gas drilling environments. The focus was on cutters incorporating ultrahard PDC (polycrystalline diamond compact) overlays (i.e., diamond tables) on tungsten-carbide substrates. Parameter variations included changes in cutter geometry, material composition,more » and processing conditions. Geometric variables were the diamond-table thickness, the cutting-edge profile, and the PDC/substrate interface configuration. Material and processing variables for the diamond table were, respectively, the diamond particle size and the sintering pressure applied during cutter fabrication. Complementary drop-impact, granite-log abrasion, linear cutting-force, and rotary-drilling tests examined the response of cutters from each lot. Substantial changes in behavior were observed from lot to lot, allowing the identification of features contributing major (factor of 10+) improvements in cutting performance for hard-rock applications. Recent field demonstrations highlight the advantages of employing enhanced cutter technology during challenging drilling operations.« less

Causes of wear of PDC bits and ways of improving their wear resistance

NASA Astrophysics Data System (ADS)

Timonin, VV; Smolentsev, AS; Shakhtorin, I. O.; Polushin, NI; Laptev, AI; Kushkhabiev, AS

2017-02-01

The scope of the paper encompasses basic factors that influence PDC bit efficiency. Feasible ways of eliminating the negatives are illustrated. The wash fluid flow in a standard bit is modeled, the resultant pattern of the bit washing is analyzed, and the recommendations are made on modification of the PDC bit design.

The application of advanced PDC concepts proves effective in south Texas

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

Dahlem, J.S.; Baxter, R.L.; Dunn, K.E.

1996-12-01

Over the years, a variety of problems with polycrystalline diamond compact (PDC) bit design and application has been documented, with bit whirl being identified as the cause of many inherent problems. The goal of most PDC manufacturers, and the subject of this paper, is development of a better-performing, whirl-resistant PDC bit design. Similarly, the goal for most operators is the lower cost resulting from effective application of such bits. Toward those ends, a cooperative development effort between operators and a manufacturer was undertaken to apply advanced concepts effectively to the design, manufacture, and application of a new series of PDCmore » bits in south Texas. Adoption of design concepts, such as force-balanced cutting structures, asymmetric blade layouts, spiral blade designs, and tracking cutter arrangements, proved effective in countering the destructive effects of bit whirl, and allowed PDC bits to be used in harder formations. Summaries of both operational and economic performance confirm the success of the undertaking.« less

GOS hook type wells, directional planning, techniques applied and problems encountered

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

A /Azim, M.; Fahmy, H.; Salem, A.

1995-10-01

This paper addresses the various aspects of hook type wells introduced and drilled within GUPCO operations during he last two years. The first well of this category was October-G10, drilled in October 1992 from October ``G`` platform to a target point in the Nubia formation. Several wells of the same type have been drilled through 1993 and 1994. This group includes October-H1, Ramadan 3-57, July 62-69 and SB 374-3. Drilling hook type well profiles has resulted in increased production and more reserve recovery. The driving force behind using this profile was the reservoir requirements where it was required to hitmore » a target within few meters at a certain angle and direction. Torque and drag models have been used to optimize well path planning, resulting in lower torque and drag values. Daily pot appraisal of the drilling operations to monitor hole cleaning effectiveness. Combination of advanced steerable systems and PDC bits enabled GUPCO to drill these wells cost effectively.« less

A study of electro-osmosis as applied to drilling engineering

NASA Astrophysics Data System (ADS)

Hariharan, Peringandoor Raman

In the present research project. the application of the process of electro-osmosis has been extended to a variety of rocks during the drilling operation. Electro-osmosis has been utilized extensively to examine its influence in reducing (i) bit balling, (ii) coefficient of friction between rock and metal and (iii) bit/tool wear. An attempt has been made to extend the envelope of confidence in which electro-osmosis was found to be operating satisfactorily. For all the above cases the current requirements during electro-osmosis were identified and were recorded. A novel test method providing repeatable results has been developed to study the problem of bit balling in the laboratory through the design of a special metallic bob simulating the drill bit. A numerical parameter described as the Degree-of-Balling (DOB) defined by the amount of cuttings stuck per unit volume of rock cut for the same duration of time is being proposed as a means to quantitatively describe the balling process in the laboratory. Five different types of shales (Pierre I & II, Catoosa, Mancos and Wellington) were compared and evaluated for balling characteristics and to determine the best conditions for reducing bit balling with electro-osmosis in a variety of drilling fluids including fresh water, polymer solutions and field type drilling fluids. Through the design, fabrication and performing of experiments conducted with a model Bottom Hole Assembly (BHA). the feasibility of maintaining the drill bit separately at a negative potential and causing the current to flow through the rock back into the string through a near bit stabilizer has been demonstrated. Experiments conducted with this self contained arrangement for the application of electro-osmosis have demonstrated a substantial decrease in balling and increase in the rate of penetration (ROP) while drilling with both a roller cone and PDC microbit (1-1/4" dia.) in Pierre I and Wellington shales. It is believed that the results obtained from the model BHA will aid in scaling up to a full-scale prototype BHA for possible application in the field. Experiments conducted with electro-osmosis in a simulated drill string under loaded conditions have clearly demonstrated that the coefficient of friction (mu) can be reduced at the interface of a rotating cylinder (simulating the drill-pipe) and a rock (usually a type of shale), through electro-osmosis. Studies examined the influence of many variables such as drilling fluid, rock type, and current on mu. The need for the correct estimation of mu is for reliable correlation between values obtained in the laboratory with those observed in the field. The knowledge of the coefficient of friction (mu) is an important requirement for drill string design and well trajectory planning. The use of electro-osmosis in reducing bit/tool wear through experiments in various rocks utilizing a specially designed steel bob simulating the drill bit has clearly indicated a decreased average tool wear, varying from 35% in Pierre I shale up to 57% in sandstone when used with the tool maintained at a cathodic DC potential. (Abstract shortened by UMI.)

Measurement and analysis of chatter in a compliant model of a drillstring equipped with a PDC bit

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

Elsayed, M.A.; Raymond, D.W.

1999-11-09

Typical laboratory testing of Polycrystalline Diamond Compact (PDC) bits is performed on relatively rigid setups. Even in hard rock, PDC bits exhibit reasonable life using such testing schemes. Unfortunately, field experience indicates otherwise. In this paper, the authors show that introducing compliance in testing setups provides better simulation of actual field conditions. Using such a scheme, they show that chatter can be severe even in softer rock, such as sandstone, and very destructive to the cutters in hard rock, such as sierra white granite.

Application program of CRUST-1 10km continental scientific drilling rig in SK-2 scientific drilling well

NASA Astrophysics Data System (ADS)

Sun, Youhong; Gao, Ke; Yu, Ping; Liu, Baochang; Guo, Wei; Ma, Yinlong; Yang, Yang

2014-05-01

SK-2 Well is located in DaQing city,where is site of the largest oil field in China,Heilongjiang province, north-east of China.The objective of SK-2 well is to obtain full cores of cretaceous formation in Song Liao basin,and to build the time tunnel of Cretaceous greenhouse climate change,and to clarify the causes,processes and results of the formations of DaQing oil field. This will ensure to achieve our ultimate goals,to test the CRUST-1 drilling rig and improve China's deep scientific drilling technology,to form the scientific drilling technology,method and system with independent intellectual property rights,and to provide technical knowledge and information for China's ten kilometers super-deep scientific drilling technical resources.SK-2 Well is at 6400 meter depth, where the drilling inclination is 90 degree and the continuous coring length is 3535 meter that from 2865 to 6400 meter,the recovery rate of the core is greater or equal to 95 percent with 100 millimeters core diameter and 3.9 degree per 100 meter geothermal gradient.The CRUST-1 rig is designated with special drilling equipment for continental scientific drilling combined to the oil drilling equipment ability with advanced geological drilling technology which is highly automatic and intelligent. CRUST-1 drilling ability is 10000 meter with the maximum hook load 700 tons, the total power is 4610 Kilowatt.CRUST-1 will be integrated with a complete set of automation equipment,including big torque hydraulic top drive,high accuracy automatic drilling rod feeding system, suspended automatic drill string discharge device,hydraulic intelligent iron roughneck,and hydraulic automatic catwalk to fully meet the drilling process requirements of SK-2.Designed with advanced drilling technique for 260 degree in the bottom of SK-2 well and hard rock,including the drilling tools of high temperature hydraulic hammer,high temperature resistance and high strength aluminum drill pipe,high temperature preparation of mud treatment and high temperature resistant cementing materials, and bionic bits,that is coupling bionic PDC tooth bit and diamond-impregnated bit for hard rock.All parts of CRUST-1 were successfully assembled along with the derrick and base lift and transported about 3456 kilometers from manufacture,GuangHan city in southwest China's Sichuan province,to the well site of SK-2 in end of 2013.SK-2 will be finished during next 4 years.

Rock Drilling Performance Evaluation by an Energy Dissipation Based Rock Brittleness Index

NASA Astrophysics Data System (ADS)

Munoz, H.; Taheri, A.; Chanda, E. K.

2016-08-01

To reliably estimate drilling performance both tool-rock interaction laws along with a proper rock brittleness index are required to be implemented. In this study, the performance of a single polycrystalline diamond compact (PDC) cutter cutting and different drilling methods including PDC rotary drilling, roller-cone rotary drilling and percussive drilling were investigated. To investigate drilling performance by rock strength properties, laboratory PDC cutting tests were performed on different rocks to obtain cutting parameters. In addition, results of laboratory and field drilling on different rocks found elsewhere in literature were used. Laboratory and field cutting and drilling test results were coupled with values of a new rock brittleness index proposed herein and developed based on energy dissipation withdrawn from the complete stress-strain curve in uniaxial compression. To quantify cutting and drilling performance, the intrinsic specific energy in rotary-cutting action, i.e. the energy consumed in pure cutting action, and drilling penetration rate values in percussive action were used. The results show that the new energy-based brittleness index successfully describes the performance of different cutting and drilling methods and therefore is relevant to assess drilling performance for engineering applications.

Development of a high-temperature diagnostics-while-drilling tool.

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

Chavira, David J.; Huey, David; Hetmaniak, Chris

2009-01-01

The envisioned benefits of Diagnostics-While-Drilling (DWD) are based on the principle that high-speed, real-time information from the downhole environment will promote better control of the drilling process. Although in practice a DWD system could provide information related to any aspect of exploration and production of subsurface resources, the current DWD system provides data on drilling dynamics. This particular set of new tools provided by DWD will allow quicker detection of problems, reduce drilling flat-time and facilitate more efficient drilling (drilling optimization) with the overarching result of decreased drilling costs. In addition to providing the driller with an improved, real-time picturemore » of the drilling conditions downhole, data generated from DWD systems provides researchers with valuable, high fidelity data sets necessary for developing and validating enhanced understanding of the drilling process. Toward this end, the availability of DWD creates a synergy with other Sandia Geothermal programs, such as the hard-rock bit program, where the introduction of alternative rock-reduction technologies are contingent on the reduction or elimination of damaging dynamic effects. More detailed descriptions of the rationale for the program and early development efforts are described in more detail by others [SAND2003-2069 and SAND2000-0239]. A first-generation low-temperature (LT) DWD system was fielded in a series of proof-of-concept tests (POC) to validate functionality. Using the LT system, DWD was subsequently used to support a single-laboratory/multiple-partner CRADA (Cooperative Research and Development Agreement) entitled Advanced Drag Bits for Hard-Rock Drilling. The drag-bit CRADA was established between Sandia and four bit companies, and involved testing of a PDC bit from each company [Wise, et al., 2003, 2004] in the same lithologic interval at the Gas Technology Institute (GTI) test facility near Catoosa, OK. In addition, the LT DWD system has been fielded in cost-sharing efforts with an industrial partner to support the development of new generation hard-rock drag bits. Following the demonstrated success of the POC DWD system, efforts were initiated in FY05 to design, fabricate and test a high-temperature (HT) capable version of the DWD system. The design temperature for the HT DWD system was 225 C. Programmatic requirements dictated that a HT DWD tool be developed during FY05 and that a working system be demonstrated before the end of FY05. During initial design discussions regarding a high-temperature system it was decided that, to the extent possible, the HT DWD system would maintain functionality similar to the low temperature system, that is, the HT DWD system would also be designed to provide the driller with real-time information on bit and bottom-hole-assembly (BHA) dynamics while drilling. Additionally, because of time and fiscal constraints associated with the HT system development, the design of the HT DWD tool would follow that of the LT tool. The downhole electronics package would be contained in a concentrically located pressure barrel and the use of externally applied strain gages with thru-tool connectors would also be used in the new design. Also, in order to maximize the potential wells available for the HT DWD system and to allow better comparison with the low-temperature design, the diameter of the tool was maintained at 7-inches. This report discusses the efforts associated with the development of a DWD system capable of sustained operation at 225 C. This report documents work performed in the second phase of the Diagnostics-While-Drilling (DWD) project in which a high-temperature (HT) version of the phase 1 low-temperature (LT) proof-of-concept (POC) DWD tool was built and tested. Descriptions of the design, fabrication and field testing of the HT tool are provided. Background on prior phases of the project can be found in SAND2003-2069 and SAND2000-0239.« less

Performance test of different 3.5 mm drill bits and consequences for orthopaedic surgery.

PubMed

Clement, Hans; Zopf, Christoph; Brandner, Markus; Tesch, Norbert P; Vallant, Rudolf; Puchwein, Paul

2015-12-01

Drilling of bones in orthopaedic and trauma surgery is a common procedure. There are yet no recommendations about which drill bits/coating should be preferred and when to change a used drill bit. In preliminary studies typical "drilling patterns" of surgeons concerning used spindle speed and feeding force were recorded. Different feeding forces were tested and abrasion was analysed using magnification and a scanning electron microscope (SEM). Acquired data were used for programming a friction stir welding machine (FSWM). Four drill bits (a default AISI 440A, a HSS, an AISI 440B and a Zirconium-oxide drill bit) were analysed for abrasive wear after 20/40/60 machine-guided and hand-driven drilled holes. Additionally different drill coatings [diamond-like carbon/grafitic (DLC), titanium nitride/carbide (Ti-N)] were tested. The mean applied feeding force by surgeons was 45 ± 15.6 Newton (N). HSS bits were still usable after 51 drill holes. Both coated AISI 440A bits showed considerable breakouts of the main cutting edge after 20 hand-driven drilled holes. The coated HSS bit showed very low abrasive wear. The non-coated AISI 440B bit had a similar durability to the HSS bits. The ZrO2 dental drill bit excelled its competitors (no considerable abrasive wear at >100 holes). If the default AISI 440A drill bit cannot be checked by 20-30× magnification after surgery, it should be replaced after 20 hand-driven drilled holes. Low price coated HSS bits could be a powerful alternative.

Drill bit assembly for releasably retaining a drill bit cutter

DOEpatents

Glowka, David A.; Raymond, David W.

2002-01-01

A drill bit assembly is provided for releasably retaining a polycrystalline diamond compact drill bit cutter. Two adjacent cavities formed in a drill bit body house, respectively, the disc-shaped drill bit cutter and a wedge-shaped cutter lock element with a removable fastener. The cutter lock element engages one flat surface of the cutter to retain the cutter in its cavity. The drill bit assembly thus enables the cutter to be locked against axial and/or rotational movement while still providing for easy removal of a worn or damaged cutter. The ability to adjust and replace cutters in the field reduces the effect of wear, helps maintains performance and improves drilling efficiency.

Heat Generation During Bone Drilling: A Comparison Between Industrial and Orthopaedic Drill Bits.

PubMed

Hein, Christopher; Inceoglu, Serkan; Juma, David; Zuckerman, Lee

2017-02-01

Cortical bone drilling for preparation of screw placement is common in multiple surgical fields. The heat generated while drilling may reach thresholds high enough to cause osteonecrosis. This can compromise implant stability. Orthopaedic drill bits are several orders more expensive than their similarly sized, publicly available industrial counterparts. We hypothesize that an industrial bit will generate less heat during drilling, and the bits will not generate more heat after multiple cortical passes. We compared 4 4.0 mm orthopaedic and 1 3.97 mm industrial drill bits. Three types of each bit were drilled into porcine femoral cortices 20 times. The temperature of the bone was measured with thermocouple transducers. The heat generated during the first 5 drill cycles for each bit was compared to the last 5 cycles. These data were analyzed with analysis of covariance. The industrial drill bit generated the smallest mean increase in temperature (2.8 ± 0.29°C) P < 0.0001. No significant difference was identified comparing the first 5 cortices drilled to the last 5 cortices drilled for each bit. The P-values are as follows: Bosch (P = 0.73), Emerge (P = 0.09), Smith & Nephew (P = 0.08), Stryker (P = 0.086), and Synthes (P = 0.16). The industrial bit generated less heat during drilling than its orthopaedic counterparts. The bits maintained their performance after 20 drill cycles. Consideration should be given by manufacturers to design differences that may contribute to a more efficient cutting bit. Further investigation into the reuse of these drill bits may be warranted, as our data suggest their efficiency is maintained after multiple uses.

A new thermal model for bone drilling with applications to orthopaedic surgery.

PubMed

Lee, JuEun; Rabin, Yoed; Ozdoganlar, O Burak

2011-12-01

This paper presents a new thermal model for bone drilling with applications to orthopaedic surgery. The new model combines a unique heat-balance equation for the system of the drill bit and the chip stream, an ordinary heat diffusion equation for the bone, and heat generation at the drill tip, arising from the cutting process and friction. Modeling of the drill bit-chip stream system assumes an axial temperature distribution and a lumped heat capacity effect in the transverse cross-section. The new model is solved numerically using a tailor-made finite-difference scheme for the drill bit-chip stream system, coupled with a classic finite-difference method for the bone. The theoretical investigation addresses the significance of heat transfer between the drill bit and the bone, heat convection from the drill bit to the surroundings, and the effect of the initial temperature of the drill bit on the developing thermal field. Using the new model, a parametric study on the effects of machining conditions and drill-bit geometries on the resulting temperature field in the bone and the drill bit is presented. Results of this study indicate that: (1) the maximum temperature in the bone decreases with increased chip flow; (2) the transient temperature distribution is strongly influenced by the initial temperature; (3) the continued cooling (irrigation) of the drill bit reduces the maximum temperature even when the tip is distant from the cooled portion of the drill bit; and (4) the maximum temperature increases with increasing spindle speed, increasing feed rate, decreasing drill-bit diameter, increasing point angle, and decreasing helix angle. The model is expected to be useful in determination of optimum drilling conditions and drill-bit geometries. Copyright © 2011. Published by Elsevier Ltd.

Effect of bit wear on hammer drill handle vibration and productivity.

PubMed

Antonucci, Andrea; Barr, Alan; Martin, Bernard; Rempel, David

2017-08-01

The use of large electric hammer drills exposes construction workers to high levels of hand vibration that may lead to hand-arm vibration syndrome and other musculoskeletal disorders. The aim of this laboratory study was to investigate the effect of bit wear on drill handle vibration and drilling productivity (e.g., drilling time per hole). A laboratory test bench system was used with an 8.3 kg electric hammer drill and 1.9 cm concrete bit (a typical drill and bit used in commercial construction). The system automatically advanced the active drill into aged concrete block under feed force control to a depth of 7.6 cm while handle vibration was measured according to ISO standards (ISO 5349 and 28927). Bits were worn to 4 levels by consecutive hole drilling to 4 cumulative drilling depths: 0, 1,900, 5,700, and 7,600 cm. Z-axis handle vibration increased significantly (p<0.05) from 4.8 to 5.1 m/s 2 (ISO weighted) and from 42.7-47.6 m/s 2 (unweighted) when comparing a new bit to a bit worn to 1,900 cm of cumulative drilling depth. Handle vibration did not increase further with bits worn more than 1900 cm of cumulative drilling depth. Neither x- nor y-axis handle vibration was effected by bit wear. The time to drill a hole increased by 58% for the bit with 5,700 cm of cumulative drilling depth compared to a new bit. Bit wear led to a small but significant increase in both ISO weighted and unweighted z-axis handle vibration. Perhaps more important, bit wear had a large effect on productivity. The effect on productivity will influence a worker's allowable daily drilling time if exposure to drill handle vibration is near the ACGIH Threshold Limit Value. [1] Construction contractors should implement a bit replacement program based on these findings.

Remote drill bit loader

DOEpatents

Dokos, J.A.

1997-12-30

A drill bit loader is described for loading a tapered shank of a drill bit into a similarly tapered recess in the end of a drill spindle. The spindle has a transverse slot at the inner end of the recess. The end of the tapered shank of the drill bit has a transverse tang adapted to engage in the slot so that the drill bit will be rotated by the spindle. The loader is in the form of a cylinder adapted to receive the drill bit with the shank projecting out of the outer end of the cylinder. Retainer pins prevent rotation of the drill bit in the cylinder. The spindle is lowered to extend the shank of the drill bit into the recess in the spindle and the spindle is rotated to align the slot in the spindle with the tang on the shank. A spring unit in the cylinder is compressed by the drill bit during its entry into the recess of the spindle and resiliently drives the tang into the slot in the spindle when the tang and slot are aligned. 5 figs.

Remote drill bit loader

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

Dokos, James A.

A drill bit loader for loading a tapered shank of a drill bit into a similarly tapered recess in the end of a drill spindle. The spindle has a transverse slot at the inner end of the recess. The end of the tapered shank of the drill bit has a transverse tang adapted to engage in the slot so that the drill bit will be rotated by the spindle. The loader is in the form of a cylinder adapted to receive the drill bit with the shank projecting out of the outer end of the cylinder. Retainer pins prevent rotationmore » of the drill bit in the cylinder. The spindle is lowered to extend the shank of the drill bit into the recess in the spindle and the spindle is rotated to align the slot in the spindle with the tang on the shank. A spring unit in the cylinder is compressed by the drill bit during its entry into the recess of the spindle and resiliently drives the tang into the slot in the spindle when the tang and slot are aligned.« less

Remote drill bit loader

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

Dokos, J.A.

A drill bit loader is described for loading a tapered shank of a drill bit into a similarly tapered recess in the end of a drill spindle. The spindle has a transverse slot at the inner end of the recess. The end of the tapered shank of the drill bit has a transverse tang adapted to engage in the slot so that the drill bit will be rotated by the spindle. The loader is in the form of a cylinder adapted to receive the drill bit with the shank projecting out of the outer end of the cylinder. Retainer pinsmore » prevent rotation of the drill bit in the cylinder. The spindle is lowered to extend the shank of the drill bit into the recess in the spindle and the spindle is rotated to align the slot in the spindle with the tang on the shank. A spring unit in the cylinder is compressed by the drill bit during its entry into the recess of the spindle and resiliently drives the tang into the slot in the spindle when the tang and slot are aligned. 5 figs.« less

Remote drill bit loader

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

Dokos, J.A.

1996-12-31

A drill bit loader is described for loading a tapered shank of a drill bit into a similarly tapered recess in the end of a drill spindle. The spindle has a transverse slot at the inner end of the recess. The end of the tapered shank of the drill bit has a transverse tang adapted to engage in the slot so that the drill bit will be rotated by the spindle. The loader is in the form of a cylinder adapted to receive the drill bit with the shank projecting out of the outer end of the cylinder. Retainer pinsmore » prevent rotation of the drill bit in the cylinder. The spindle is lowered to extend the shank of the drill bit into the recess in the spindle and the spindle is rotated to align the slot in the spindle with the tang on the shank. A spring unit in the cylinder is compressed by the drill bit during its entry into the recess of the spindle and resiliently drives the tang into the slot in the spindle when the tang and slot are aligned. In typical remote drilling operations, whether in hot cells or water pits, drill bits have been held using a collet or end mill type holder with set screws. In either case, to load or change a drill bit required the use master-slave manipulators to position the bits and tighten the collet or set screws. This requirement eliminated many otherwise useful work areas because they were not equipped with slaves, particularly in water pits.« less

Modeling and Analysis of Gated, Pulsed RFI and Its Effect on GPS Receivers: Analysis of Average Cycle Slip Rate and Average Bit Error Probability

DTIC Science & Technology

2014-04-01

as a function of the pulse duty cycle PDC is [1]: ∆C/N0 = 20 log(1 − PDC ) (1) PDC , PW × PRF (2) where PW represents the pulse width (sec) and PRF is...corresponding degradation in C/N0 should now be modeled as ∆C/N0 = 20 log(1 − PDCLIM) (3) PDCLIM , PDC τobs TTC . (4) The degradation model of Eqn. 3 and 4...cycle that is the product of the duty cycle of the pulsed waveform ( PDC ) and the duty cycle of the of the gating waveform (τobs/TTC). While such a model

Drilling subsurface wellbores with cutting structures

DOEpatents

Mansure, Arthur James; Guimerans, Rosalvina Ramona

2010-11-30

A system for forming a wellbore includes a drill tubular. A drill bit is coupled to the drill tubular. One or more cutting structures are coupled to the drill tubular above the drill bit. The cutting structures remove at least a portion of formation that extends into the wellbore formed by the drill bit.

Core drill's bit is replaceable without withdrawal of drill stem - A concept

NASA Technical Reports Server (NTRS)

Rushing, F. C.; Simon, A. B.

1970-01-01

Drill bit is divided into several sectors. When collapsed, the outside diameter is forced down the drill stem, when it reaches bottom the sectors are forced outward and form a cutting bit. A dulled bit is retracted by reversal of this procedure.

Evaluations of bit sleeve and twisted-body bit designs for controlling roof bolter dust

PubMed Central

Beck, T.W.

2015-01-01

Drilling into coal mine roof strata to install roof bolts has the potential to release substantial quantities of respirable dust. Due to the proximity of drill holes to the breathing zone of roof bolting personnel, dust escaping the holes and avoiding capture by the dust collection system pose a potential respiratory health risk. Controls are available to complement the typical dry vacuum collection system and minimize harmful exposures during the initial phase of drilling. This paper examines the use of a bit sleeve in combination with a dust-hog-type bit to improve dust extraction during the critical initial phase of drilling. A twisted-body drill bit is also evaluated to determine the quantity of dust liberated in comparison with the dust-hog-type bit. Based on the results of our laboratory tests, the bit sleeve may reduce dust emissions by one-half during the initial phase of drilling before the drill bit is fully enclosed by the drill hole. Because collaring is responsible for the largest dust liberations, overall dust emission can also be substantially reduced. The use of a twisted-body bit has minimal improvement on dust capture compared with the commonly used dust-hog-type bit. PMID:26257435

Percussive Augmenter of Rotary Drills for Operating as a Rotary-Hammer Drill

NASA Technical Reports Server (NTRS)

Aldrich, Jack Barron (Inventor); Bar-Cohen, Yoseph (Inventor); Sherrit, Stewart (Inventor); Badescu, Mircea (Inventor); Bao, Xiaoqi (Inventor); Scott, James Samson (Inventor)

2014-01-01

A percussive augmenter bit includes a connection shaft for mounting the bit onto a rotary drill. In a first modality, an actuator percussively drives the bit, and an electric slip-ring provides power to the actuator while being rotated by the drill. Hammering action from the actuator and rotation from the drill are applied directly to material being drilled. In a second modality, a percussive augmenter includes an actuator that operates as a hammering mechanism that drives a free mass into the bit creating stress pulses that fracture material that is in contact with the bit.

Hydromechanical drilling device

DOEpatents

Summers, David A.

1978-01-01

A hydromechanical drilling tool which combines a high pressure water jet drill with a conventional roller cone type of drilling bit. The high pressure jet serves as a tap drill for cutting a relatively small diameter hole in advance of the conventional bit. Auxiliary laterally projecting jets also serve to partially cut rock and to remove debris from in front of the bit teeth thereby reducing significantly the thrust loading for driving the bit.

HIGH-POWER TURBODRILL AND DRILL BIT FOR DRILLING WITH COILED TUBING

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

Robert Radtke; David Glowka; Man Mohan Rai

2008-03-31

Commercial introduction of Microhole Technology to the gas and oil drilling industry requires an effective downhole drive mechanism which operates efficiently at relatively high RPM and low bit weight for delivering efficient power to the special high RPM drill bit for ensuring both high penetration rate and long bit life. This project entails developing and testing a more efficient 2-7/8 in. diameter Turbodrill and a novel 4-1/8 in. diameter drill bit for drilling with coiled tubing. The high-power Turbodrill were developed to deliver efficient power, and the more durable drill bit employed high-temperature cutters that can more effectively drill hardmore » and abrasive rock. This project teams Schlumberger Smith Neyrfor and Smith Bits, and NASA AMES Research Center with Technology International, Inc (TII), to deliver a downhole, hydraulically-driven power unit, matched with a custom drill bit designed to drill 4-1/8 in. boreholes with a purpose-built coiled tubing rig. The U.S. Department of Energy National Energy Technology Laboratory has funded Technology International Inc. Houston, Texas to develop a higher power Turbodrill and drill bit for use in drilling with a coiled tubing unit. This project entails developing and testing an effective downhole drive mechanism and a novel drill bit for drilling 'microholes' with coiled tubing. The new higher power Turbodrill is shorter, delivers power more efficiently, operates at relatively high revolutions per minute, and requires low weight on bit. The more durable thermally stable diamond drill bit employs high-temperature TSP (thermally stable) diamond cutters that can more effectively drill hard and abrasive rock. Expectations are that widespread adoption of microhole technology could spawn a wave of 'infill development' drilling of wells spaced between existing wells, which could tap potentially billions of barrels of bypassed oil at shallow depths in mature producing areas. At the same time, microhole coiled tube drilling offers the opportunity to dramatically cut producers' exploration risk to a level comparable to that of drilling development wells. Together, such efforts hold great promise for economically recovering a sizeable portion of the estimated remaining shallow (less than 5,000 feet subsurface) oil resource in the United States. The DOE estimates this U.S. targeted shallow resource at 218 billion barrels. Furthermore, the smaller 'footprint' of the lightweight rigs utilized for microhole drilling and the accompanying reduced drilling waste disposal volumes offer the bonus of added environmental benefits. DOE analysis shows that microhole technology has the potential to cut exploratory drilling costs by at least a third and to slash development drilling costs in half.« less

Ultrasonic rotary-hammer drill

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoseph (Inventor); Badescu, Mircea (Inventor); Sherrit, Stewart (Inventor); Kassab, Steve (Inventor); Bao, Xiaoqi (Inventor)

2010-01-01

A mechanism for drilling or coring by a combination of sonic hammering and rotation. The drill includes a hammering section with a set of preload weights mounted atop a hammering actuator and an axial passage through the hammering section. In addition, a rotary section includes a motor coupled to a drive shaft that traverses the axial passage through the hammering section. A drill bit is coupled to the drive shaft for drilling by a combination of sonic hammering and rotation. The drill bit includes a fluted shaft leading to a distal crown cutter with teeth. The bit penetrates sampled media by repeated hammering action. In addition, the bit is rotated. As it rotates the fluted bit carries powdered cuttings helically upward along the side of the bit to the surface.

Reducing temperature elevation of robotic bone drilling.

PubMed

Feldmann, Arne; Wandel, Jasmin; Zysset, Philippe

2016-12-01

This research work aims at reducing temperature elevation of bone drilling. An extensive experimental study was conducted which focused on the investigation of three main measures to reduce the temperature elevation as used in industry: irrigation, interval drilling and drill bit designs. Different external irrigation rates (0 ml/min, 15 ml/min, 30 ml/min), continuously drilled interval lengths (2 mm, 1 mm, 0.5 mm) as well as two drill bit designs were tested. A custom single flute drill bit was designed with a higher rake angle and smaller chisel edge to generate less heat compared to a standard surgical drill bit. A new experimental setup was developed to measure drilling forces and torques as well as the 2D temperature field at any depth using a high resolution thermal camera. The results show that external irrigation is a main factor to reduce temperature elevation due not primarily to its effect on cooling but rather due to the prevention of drill bit clogging. During drilling, the build up of bone material in the drill bit flutes result in excessive temperatures due to an increase in thrust forces and torques. Drilling in intervals allows the removal of bone chips and cleaning of flutes when the drill bit is extracted as well as cooling of the bone in-between intervals which limits the accumulation of heat. However, reducing the length of the drilled interval was found only to be beneficial for temperature reduction using the newly designed drill bit due to the improved cutting geometry. To evaluate possible tissue damage caused by the generated heat increase, cumulative equivalent minutes (CEM43) were calculated and it was found that the combination of small interval length (0.5 mm), high irrigation rate (30 ml/min) and the newly designed drill bit was the only parameter combination which allowed drilling below the time-thermal threshold for tissue damage. In conclusion, an optimized drilling method has been found which might also enable drilling in more delicate procedures such as that performed during minimally invasive robotic cochlear implantation. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

Mars Rover Step Toward Possible Resumption of Drilling

NASA Image and Video Library

2017-10-23

NASA's Curiosity Mars rover conducted a test on Oct. 17, 2017, as part of the rover team's development of a new way to use the rover's drill. This image from Curiosity's front Hazard Avoidance Camera (Hazcam) shows the drill's bit touching the ground during an assessment of measurements by a sensor on the rover's robotic arm. Curiosity used its drill to acquire sample material from Martian rocks 15 times from 2013 to 2016. In December 2016, the drill's feed mechanism stopped working reliably. During the test shown in this image, the rover touched the drill bit to the ground for the first time in 10 months. The image has been adjusted to brighten shaded areas so that the bit is more evident. The date was the 1,848th Martian day, or sol, of Curiosity's work on Mars In drill use prior to December 2016, two contact posts -- the stabilizers on either side of the bit -- were placed on the target rock while the bit was in a withdrawn position. Then the motorized feed mechanism within the drill extended the bit forward, and the bit's rotation and percussion actions penetrated the rock. A promising alternative now under development and testing -- called feed-extended drilling -- uses motion of the robotic arm to directly advance the extended bit into a rock. In this image, the bit is touching the ground but the stabilizers are not. In the Sol 1848 activity, Curiosity pressed the drill bit downward, and then applied smaller sideways forces while taking measurements with a force/torque sensor on the arm. The objective was to gain understanding about how readings from the sensor can be used during drilling to adjust for any sideways pressure that might risk the bit becoming stuck in a rock. While rover-team engineers are working on an alternative drilling method, the mission continues to examine sites on Mount Sharp, Mars, with other tools. https://photojournal.jpl.nasa.gov/catalog/PIA22063

Bit selection using field drilling data and mathematical investigation

NASA Astrophysics Data System (ADS)

Momeni, M. S.; Ridha, S.; Hosseini, S. J.; Meyghani, B.; Emamian, S. S.

2018-03-01

A drilling process will not be complete without the usage of a drill bit. Therefore, bit selection is considered to be an important task in drilling optimization process. To select a bit is considered as an important issue in planning and designing a well. This is simply because the cost of drilling bit in total cost is quite high. Thus, to perform this task, aback propagation ANN Model is developed. This is done by training the model using several wells and it is done by the usage of drilling bit records from offset wells. In this project, two models are developed by the usage of the ANN. One is to find predicted IADC bit code and one is to find Predicted ROP. Stage 1 was to find the IADC bit code by using all the given filed data. The output is the Targeted IADC bit code. Stage 2 was to find the Predicted ROP values using the gained IADC bit code in Stage 1. Next is Stage 3 where the Predicted ROP value is used back again in the data set to gain Predicted IADC bit code value. The output is the Predicted IADC bit code. Thus, at the end, there are two models that give the Predicted ROP values and Predicted IADC bit code values.

Drilling systems for extraterrestrial subsurface exploration.

PubMed

Zacny, K; Bar-Cohen, Y; Brennan, M; Briggs, G; Cooper, G; Davis, K; Dolgin, B; Glaser, D; Glass, B; Gorevan, S; Guerrero, J; McKay, C; Paulsen, G; Stanley, S; Stoker, C

2008-06-01

Drilling consists of 2 processes: breaking the formation with a bit and removing the drilled cuttings. In rotary drilling, rotational speed and weight on bit are used to control drilling, and the optimization of these parameters can markedly improve drilling performance. Although fluids are used for cuttings removal in terrestrial drilling, most planetary drilling systems conduct dry drilling with an auger. Chip removal via water-ice sublimation (when excavating water-ice-bound formations at pressure below the triple point of water) and pneumatic systems are also possible. Pneumatic systems use the gas or vaporization products of a high-density liquid brought from Earth, gas provided by an in situ compressor, or combustion products of a monopropellant. Drill bits can be divided into coring bits, which excavate an annular shaped hole, and full-faced bits. While cylindrical cores are generally superior as scientific samples, and coring drills have better performance characteristics, full-faced bits are simpler systems because the handling of a core requires a very complex robotic mechanism. The greatest constraints to extraterrestrial drilling are (1) the extreme environmental conditions, such as temperature, dust, and pressure; (2) the light-time communications delay, which necessitates highly autonomous systems; and (3) the mission and science constraints, such as mass and power budgets and the types of drilled samples needed for scientific analysis. A classification scheme based on drilling depth is proposed. Each of the 4 depth categories (surface drills, 1-meter class drills, 10-meter class drills, and deep drills) has distinct technological profiles and scientific ramifications.

Downhole telemetry system

DOEpatents

Normann, R.A.; Kadlec, E.R.

1994-11-08

A downhole telemetry system is described for optically communicating to the surface operating parameters of a drill bit during ongoing drilling operations. The downhole telemetry system includes sensors mounted with a drill bit for monitoring at least one operating parameter of the drill bit and generating a signal representative thereof. The downhole telemetry system includes means for transforming and optically communicating the signal to the surface as well as means at the surface for producing a visual display of the optically communicated operating parameters of the drill bit. 7 figs.

Downhole telemetry system

DOEpatents

Normann, Randy A.; Kadlec, Emil R.

1994-01-01

A downhole telemetry system is described for optically communicating to the surface operating parameters of a drill bit during ongoing drilling operations. The downhole telemetry system includes sensors mounted with a drill bit for monitoring at least one operating parameter of the drill bit and generating a signal representative thereof. The downhole telemetry system includes means for transforming and optically communicating the signal to the surface as well as means at the surface for producing a visual display of the optically communicated operating parameters of the drill bit.

Design and testing of coring bits on drilling lunar rock simulant

NASA Astrophysics Data System (ADS)

Li, Peng; Jiang, Shengyuan; Tang, Dewei; Xu, Bo; Ma, Chao; Zhang, Hui; Qin, Hongwei; Deng, Zongquan

2017-02-01

Coring bits are widely utilized in the sampling of celestial bodies, and their drilling behaviors directly affect the sampling results and drilling security. This paper introduces a lunar regolith coring bit (LRCB), which is a key component of sampling tools for lunar rock breaking during the lunar soil sampling process. We establish the interaction model between the drill bit and rock at a small cutting depth, and the two main influential parameters (forward and outward rake angles) of LRCB on drilling loads are determined. We perform the parameter screening task of LRCB with the aim to minimize the weight on bit (WOB). We verify the drilling load performances of LRCB after optimization, and the higher penetrations per revolution (PPR) are, the larger drilling loads we gained. Besides, we perform lunar soil drilling simulations to estimate the efficiency on chip conveying and sample coring of LRCB. The results of the simulation and test are basically consistent on coring efficiency, and the chip removal efficiency of LRCB is slightly lower than HIT-H bit from simulation. This work proposes a method for the design of coring bits in subsequent extraterrestrial explorations.

77 FR 51825 - Certain Drill Bits and Products Containing Same; Determination To Review an Initial Determination...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-27

... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-844] Certain Drill Bits and Products... sale for importation, and the sale within the United States after importation of certain drill bits and... Christensen Trading Inc. of Panama; and Intermountain Drilling Supply Corp. of West Valley City, Utah. On June...

Optimization of Deep Drilling Performance - Development and Benchmark Testing of Advanced Diamond Product Drill Bits & HP/HT Fluids to Significantly Improve Rates of Penetration

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

Alan Black; Arnis Judzis

2005-09-30

This document details the progress to date on the OPTIMIZATION OF DEEP DRILLING PERFORMANCE--DEVELOPMENT AND BENCHMARK TESTING OF ADVANCED DIAMOND PRODUCT DRILL BITS AND HP/HT FLUIDS TO SIGNIFICANTLY IMPROVE RATES OF PENETRATION contract for the year starting October 2004 through September 2005. The industry cost shared program aims to benchmark drilling rates of penetration in selected simulated deep formations and to significantly improve ROP through a team development of aggressive diamond product drill bit--fluid system technologies. Overall the objectives are as follows: Phase 1--Benchmark ''best in class'' diamond and other product drilling bits and fluids and develop concepts for amore » next level of deep drilling performance; Phase 2--Develop advanced smart bit-fluid prototypes and test at large scale; and Phase 3--Field trial smart bit--fluid concepts, modify as necessary and commercialize products. As of report date, TerraTek has concluded all Phase 1 testing and is planning Phase 2 development.« less

"Push back" technique: A simple method to remove broken drill bit from the proximal femur.

PubMed

Chouhan, Devendra K; Sharma, Siddhartha

2015-11-18

Broken drill bits can be difficult to remove from the proximal femur and may necessitate additional surgical exploration or special instrumentation. We present a simple technique to remove a broken drill bit that does not require any special instrumentation and can be accomplished through the existing incision. This technique is useful for those cases where the length of the broken drill bit is greater than the diameter of the bone.

77 FR 32997 - Certain Drill Bits and Products Containing the Same; Institution of Investigation Pursuant to 19...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-04

... INTERNATIONAL TRADE COMMISSION [Inv. No. 337-TA-844] Certain Drill Bits and Products Containing... drill bits and products containing the same by reason of infringement of certain claims of U.S. Patent... States, the sale for importation, or the sale within the United States after importation of certain drill...

Optimization of Deep Drilling Performance--Development and Benchmark Testing of Advanced Diamond Product Drill Bits & HP/HT Fluids to Significantly Improve Rates of Penetration

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

Alan Black; Arnis Judzis

2003-10-01

This document details the progress to date on the OPTIMIZATION OF DEEP DRILLING PERFORMANCE--DEVELOPMENT AND BENCHMARK TESTING OF ADVANCED DIAMOND PRODUCT DRILL BITS AND HP/HT FLUIDS TO SIGNIFICANTLY IMPROVE RATES OF PENETRATION contract for the year starting October 2002 through September 2002. The industry cost shared program aims to benchmark drilling rates of penetration in selected simulated deep formations and to significantly improve ROP through a team development of aggressive diamond product drill bit--fluid system technologies. Overall the objectives are as follows: Phase 1--Benchmark ''best in class'' diamond and other product drilling bits and fluids and develop concepts for amore » next level of deep drilling performance; Phase 2--Develop advanced smart bit--fluid prototypes and test at large scale; and Phase 3--Field trial smart bit--fluid concepts, modify as necessary and commercialize products. Accomplishments to date include the following: 4Q 2002--Project started; Industry Team was assembled; Kick-off meeting was held at DOE Morgantown; 1Q 2003--Engineering meeting was held at Hughes Christensen, The Woodlands Texas to prepare preliminary plans for development and testing and review equipment needs; Operators started sending information regarding their needs for deep drilling challenges and priorities for large-scale testing experimental matrix; Aramco joined the Industry Team as DEA 148 objectives paralleled the DOE project; 2Q 2003--Engineering and planning for high pressure drilling at TerraTek commenced; 3Q 2003--Continuation of engineering and design work for high pressure drilling at TerraTek; Baker Hughes INTEQ drilling Fluids and Hughes Christensen commence planning for Phase 1 testing--recommendations for bits and fluids.« less

Testing New Techniques for Mars Rover Rock-Drilling

NASA Image and Video Library

2017-10-23

In the summer and fall of 2017, the team operating NASA's Curiosity Mars rover conducted tests in the "Mars Yard" at NASA's Jet Propulsion Laboratory, Pasadena, California, to develop techniques that Curiosity might be able to use to resume drilling into rocks on Mars. JPL robotics engineer Vladimir Arutyunov, in this June 29, 2017, photo, checks the test rover's drill bit at its contact point with a rock. Note that the stabilizer post visible to the right of the bit is not in contact with the rock, unlike the positioning used and photographed by Curiosity when drilling into rocks on Mars in 2013 to 2016. In late 2016, after Curiosity's drill had collected sample material from 15 Martian rocks, the drill's feed mechanism ceased working reliably. That motorized mechanism moved the bit forward or back with relation to the stabilizer posts on either side of the bit. In normal drilling by Curiosity, the stabilizers were positioned on the target rock first, and then the feed mechanism extended the rotation-percussion bit into the rock. In the alternative technique seen here, called "feed-extended drilling," the test rover's stabilizers are not used to touch the rock. The bit is advanced into the rock by motion of the robotic arm rather than the drill's feed mechanism. https://photojournal.jpl.nasa.gov/catalog/PIA22061

Laser-Mechanical Drilling for Geothermal Energy: Low-Contact Drilling Technology to Enable Economical EGS Wells

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

None

2010-01-15

Broad Funding Opportunity Announcement Project: Foro Energy is developing a unique capability and hardware system to transmit high power lasers over long distances via fiber optic cables. This laser power is integrated with a mechanical drilling bit to enable rapid and sustained penetration of hard rock formations too costly to drill with mechanical drilling bits alone. The laser energy that is directed at the rock basically softens the rock, allowing the mechanical bit to more easily remove it. Foro Energy’s laser-assisted drill bits have the potential to be up to 10 times more economical than conventional hard-rock drilling technologies, makingmore » them an effective way to access the U.S. energy resources currently locked under hard rock formations.« less

Assessing the efficiency of carbide drill bits and factors influencing their application to debris-rich subglacial ice

NASA Astrophysics Data System (ADS)

Yang, Cheng; Jiang, Jianliang; Cao, Pinlu; Wang, Jinsong; Fan, Xiaopeng; Shang, Yuequan; Talalay, Pavel

2017-09-01

When drilling into subglacial bedrock, drill operators commonly encounter basal ice containing high concentrations of rock debris and melt water. As such conditions can easily damage conventional ice drills, researchers have experimented with carbide, diamond, and polycrystalline diamond compact drill bits, with varying degrees of success. In this study, we analyzed the relationship between drilling speed and power consumption for a carbide drill bit penetrating debris-rich ice. We also assessed drill load, rotation speed, and various performance parameters for the cutting element, as well as the physical and mechanical properties of rock and ice, to construct mathematical models. We show that our modeled results are in close agreement with the experimental data, and that both penetration speed and power consumption are positively correlated with drill speed and load. When used in ice with 30% rock content, the maximum penetration speed of the carbide bit is 3.4 mm/s with a power consumption of ≤0.5 kW, making the bit suitable for use with existing electromechanical drills. Our study also provides a guide for further research into cutting heat and equipment design.

Ultrasonic drilling apparatus

DOEpatents

Duran, Edward L.; Lundin, Ralph L.

1989-01-01

Apparatus attachable to an ultrasonic drilling machine for drilling deep holes in very hard materials, such as boron carbide, is provided. The apparatus utilizes a hollow spindle attached to the output horn of the ultrasonic drilling machine. The spindle has a hollow drill bit attached at the opposite end. A housing surrounds the spindle, forming a cavity for holding slurry. In operation, slurry is provided into the housing, and into the spindle through inlets while the spindle is rotating and ultrasonically reciprocating. Slurry flows through the spindle and through the hollow drill bit to cleanse the cutting edge of the bit during a drilling operation.

Ultrasonic drilling apparatus

DOEpatents

Duran, E.L.; Lundin, R.L.

1988-06-20

Apparatus attachable to an ultrasonic drilling machine for drilling deep holes in very hard materials, such as boron carbide, is provided. The apparatus utilizes a hollow spindle attached to the output horn of the ultrasonic drilling machine. The spindle has a hollow drill bit attached at the opposite end. A housing surrounds the spindle, forming a cavity for holding slurry. In operation, slurry is provided into the housing, and into the spindle through inlets while the spindle is rotating and ultrasonically reciprocating. Slurry flows through the spindle and through the hollow drill bit to cleanse the cutting edge of the bit during a drilling operation. 3 figs.

OPTIMIZATION OF DEEP DRILLING PERFORMANCE--DEVELOPMENT AND BENCHMARK TESTING OF ADVANCED DIAMOND PRODUCT DRILL BITS & HP/HT FLUIDS TO SIGNIFICANTLY IMPROVE RATES OF PENETRATION

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

Alan Black; Arnis Judzis

2004-10-01

The industry cost shared program aims to benchmark drilling rates of penetration in selected simulated deep formations and to significantly improve ROP through a team development of aggressive diamond product drill bit--fluid system technologies. Overall the objectives are as follows: Phase 1--Benchmark ''best in class'' diamond and other product drilling bits and fluids and develop concepts for a next level of deep drilling performance; Phase 2--Develop advanced smart bit-fluid prototypes and test at large scale; and Phase 3--Field trial smart bit-fluid concepts, modify as necessary and commercialize products. As of report date, TerraTek has concluded all major preparations for themore » high pressure drilling campaign. Baker Hughes encountered difficulties in providing additional pumping capacity before TerraTek's scheduled relocation to another facility, thus the program was delayed further to accommodate the full testing program.« less

Laboratory Equipment for Investigation of Coring Under Mars-like Conditions

NASA Astrophysics Data System (ADS)

Zacny, K.; Cooper, G.

2004-12-01

To develop a suitable drill bit and set of operating conditions for Mars sample coring applications, it is essential to make tests under conditions that match those of the mission. The goal of the laboratory test program was to determine the drilling performance of diamond-impregnated bits under simulated Martian conditions, particularly those of low pressure and low temperature in a carbon dioxide atmosphere. For this purpose, drilling tests were performed in a vacuum chamber kept at a pressure of 5 torr. Prior to drilling, a rock, soil or a clay sample was cooled down to minus 80 degrees Celsius (Zacny et al, 2004). Thus, all Martian conditions, except the low gravity were simulated in the controlled environment. Input drilling parameters of interest included the weight on bit and rotational speed. These two independent variables were controlled from a PC station. The dependent variables included the bit reaction torque, the depth of the bit inside the drilled hole and the temperatures at various positions inside the drilled sample, in the center of the core as it was being cut and at the bit itself. These were acquired every second by a data acquisition system. Additional information such as the rate of penetration and the drill power were calculated after the test was completed. The weight of the rock and the bit prior to and after the test were measured to aid in evaluating the bit performance. In addition, the water saturation of the rock was measured prior to the test. Finally, the bit was viewed under the Scanning Electron Microscope and the Stereo Optical Microscope. The extent of the bit wear and its salient features were captured photographically. The results revealed that drilling or coring under Martian conditions in a water saturated rock is different in many respects from drilling on Earth. This is mainly because the Martian atmospheric pressure is in the vicinity of the pressure at the triple point of water. Thus ice, heated by contact with the rotating bit, sublimed and released water vapor. The volumetric expansion of ice turning into a vapor was over 150 000 times. This continuously generated volume of gas effectively cleared the freeze-dried rock cuttings from the bottom of the hole. In addition, the subliming ice provided a powerful cooling effect that kept the bit cold and preserved the core in its original state. Keeping the rock core below freezing also reduced drastically the chances of cross contamination. To keep the bit cool in near vacuum conditions where convective cooling is poor, some intermittent stops would have to be made. Under virtually the same drilling conditions, coring under Martian low temperature and pressure conditions consumed only half the power while doubling the rate of penetration as compared to drilling under Earth atmospheric conditions. However, the rate of bit wear was much higher under Martian conditions (Zacny and Cooper, 2004) References Zacny, K. A., M. C. Quayle, and G. A. Cooper (2004), Laboratory drilling under Martian conditions yields unexpected results, J. Geophys. Res., 109, E07S16, doi:10.1029/2003JE002203. Zacny, K. A., and G. A. Cooper (2004), Investigation of diamond-impregnated drill bit wear while drilling under Earth and Mars conditions, J. Geophys. Res., 109, E07S10, doi:10.1029/2003JE002204. Acknowledgments The research supported by the NASA Astrobiology, Science and Technology Instrument Development (ASTID) program.

High Temperature 300°C Directional Drilling System

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

Chatterjee, Kamalesh; Aaron, Dick; Macpherson, John

2015-07-31

Many countries around the world, including the USA, have untapped geothermal energy potential. Enhanced Geothermal Systems (EGS) technology is needed to economically utilize this resource. Temperatures in some EGS reservoirs can exceed 300°C. To effectively utilize EGS resources, an array of injector and production wells must be accurately placed in the formation fracture network. This requires a high temperature directional drilling system. Most commercial services for directional drilling systems are rated for 175°C while geothermal wells require operation at much higher temperatures. Two U.S. Department of Energy (DOE) Geothermal Technologies Program (GTP) projects have been initiated to develop a 300°Cmore » capable directional drilling system, the first developing a drill bit, directional motor, and drilling fluid, and the second adding navigation and telemetry systems. This report is for the first project, “High Temperature 300°C Directional Drilling System, including drill bit, directional motor and drilling fluid, for enhanced geothermal systems,” award number DE-EE0002782. The drilling system consists of a drill bit, a directional motor, and drilling fluid. The DOE deliverables are three prototype drilling systems. We have developed three drilling motors; we have developed four roller-cone and five Kymera® bits; and finally, we have developed a 300°C stable drilling fluid, along with a lubricant additive for the metal-to-metal motor. Metal-to-metal directional motors require coatings to the rotor and stator for wear and corrosion resistance, and this coating research has been a significant part of the project. The drill bits performed well in the drill bit simulator test, and the complete drilling system has been tested drilling granite at Baker Hughes’ Experimental Test Facility in Oklahoma. The metal-to-metal motor was additionally subjected to a flow loop test in Baker Hughes’ Celle Technology Center in Germany, where it ran for more than 100 hours.« less

Estimating Hardness from the USDC Tool-Bit Temperature Rise

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoseph; Sherrit, Stewart

2008-01-01

A method of real-time quantification of the hardness of a rock or similar material involves measurement of the temperature, as a function of time, of the tool bit of an ultrasonic/sonic drill corer (USDC) that is being used to drill into the material. The method is based on the idea that, other things being about equal, the rate of rise of temperature and the maximum temperature reached during drilling increase with the hardness of the drilled material. In this method, the temperature is measured by means of a thermocouple embedded in the USDC tool bit near the drilling tip. The hardness of the drilled material can then be determined through correlation of the temperature-rise-versus-time data with time-dependent temperature rises determined in finite-element simulations of, and/or experiments on, drilling at various known rates of advance or known power levels through materials of known hardness. The figure presents an example of empirical temperature-versus-time data for a particular 3.6-mm USDC bit, driven at an average power somewhat below 40 W, drilling through materials of various hardness levels. The temperature readings from within a USDC tool bit can also be used for purposes other than estimating the hardness of the drilled material. For example, they can be especially useful as feedback to control the driving power to prevent thermal damage to the drilled material, the drill bit, or both. In the case of drilling through ice, the temperature readings could be used as a guide to maintaining sufficient drive power to prevent jamming of the drill by preventing refreezing of melted ice in contact with the drill.

The Effects of Bit Wear on Respirable Silica Dust, Noise and Productivity: A Hammer Drill Bench Study.

PubMed

Carty, Paul; Cooper, Michael R; Barr, Alan; Neitzel, Richard L; Balmes, John; Rempel, David

2017-07-01

Hammer drills are used extensively in commercial construction for drilling into concrete for tasks including rebar installation for structural upgrades and anchor bolt installation. This drilling task can expose workers to respirable silica dust and noise. The aim of this pilot study was to evaluate the effects of bit wear on respirable silica dust, noise, and drilling productivity. Test bits were worn to three states by drilling consecutive holes to different cumulative drilling depths: 0, 780, and 1560 cm. Each state of bit wear was evaluated by three trials (nine trials total). For each trial, an automated laboratory test bench system drilled 41 holes 1.3 cm diameter, and 10 cm deep into concrete block at a rate of one hole per minute using a commercially available hammer drill and masonry bits. During each trial, dust was continuously captured by two respirable and one inhalable sampling trains and noise was sampled with a noise dosimeter. The room was thoroughly cleaned between trials. When comparing results for the sharp (0 cm) versus dull bit (1560 cm), the mean respirable silica increased from 0.41 to 0.74 mg m-3 in sampler 1 (P = 0.012) and from 0.41 to 0.89 mg m-3 in sampler 2 (P = 0.024); levels above the NIOSH recommended exposure limit of 0.05 mg m-3. Likewise, mean noise levels increased from 112.8 to 114.4 dBA (P < 0.00001). Drilling productivity declined with increasing wear from 10.16 to 7.76 mm s-1 (P < 0.00001). Increasing bit wear was associated with increasing respirable silica dust and noise and reduced drilling productivity. The levels of dust and noise produced by these experimental conditions would require dust capture, hearing protection, and possibly respiratory protection. The findings support the adoption of a bit replacement program by construction contractors. © The Author 2017. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Methods to ensure optimal off-bottom and drill bit distance under pellet impact drilling

NASA Astrophysics Data System (ADS)

Kovalyov, A. V.; Isaev, Ye D.; Vagapov, A. R.; Urnish, V. V.; Ulyanova, O. S.

2016-09-01

The paper describes pellet impact drilling which could be used to increase the drilling speed and the rate of penetration when drilling hard rock for various purposes. Pellet impact drilling implies rock destruction by metal pellets with high kinetic energy in the immediate vicinity of the earth formation encountered. The pellets are circulated in the bottom hole by a high velocity fluid jet, which is the principle component of the ejector pellet impact drill bit. The paper presents the survey of methods ensuring an optimal off-bottom and a drill bit distance. The analysis of methods shows that the issue is topical and requires further research.

Mars Science Laboratory Drill

NASA Technical Reports Server (NTRS)

Okon, Avi B.

2010-01-01

The Drill for the Mars Science Laboratory mission is a rotary-percussive sample acquisition device with an emphasis on toughness and robustness to handle the harsh environment on Mars. The unique challenges associated with autonomous drilling from a mobile robot are addressed. A highly compressed development schedule dictated a modular design architecture that satisfies the functional and load requirements while allowing independent development and testing of the Drill subassemblies. The Drill consists of four actuated mechanisms: a spindle that rotates the bit, a chuck that releases and engages bits, a novel voice-coil-based percussion mechanism that hammers the bit, and a linear translation mechanism. The Drill has three passive mechanisms: a replaceable bit assembly that acquires and collects sample, a contact sensor / stabilizer mechanism, and, lastly a flex harness service loop. This paper describes the various mechanisms that makeup the Drill and discusses the solutions to their unique design and development challenges.

Effects of size on three-cone bit performance in laboratory drilled shale

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

Black, A.D.; DiBona, B.G.; Sandstrom, J.L.

1982-09-01

The effects of size on the performance of 3-cone bits were measured during laboratory drilling tests in shale at simulated downhole conditions. Four Reed HP-SM 3-cone bits with diameters of 6 1/2, 7 7/8, 9 1/2 and 11 inches were used to drill Mancos shale with water-based mud. The tests were conducted at constant borehole pressure, two conditions of hydraulic horsepower per square inch of bit area, three conditions of rotary speed and four conditions of weight-on-bit per inch of bit diameter. The resulting penetration rates and torques were measured. Statistical techniques were used to analyze the data.

A Parametric Study for the Design of an Optimized Ultrasonic Percussive Planetary Drill Tool.

PubMed

Li, Xuan; Harkness, Patrick; Worrall, Kevin; Timoney, Ryan; Lucas, Margaret

2017-03-01

Traditional rotary drilling for planetary rock sampling, in situ analysis, and sample return are challenging because the axial force and holding torque requirements are not necessarily compatible with lightweight spacecraft architectures in low-gravity environments. This paper seeks to optimize an ultrasonic percussive drill tool to achieve rock penetration with lower reacted force requirements, with a strategic view toward building an ultrasonic planetary core drill (UPCD) device. The UPCD is a descendant of the ultrasonic/sonic driller/corer technique. In these concepts, a transducer and horn (typically resonant at around 20 kHz) are used to excite a toroidal free mass that oscillates chaotically between the horn tip and drill base at lower frequencies (generally between 10 Hz and 1 kHz). This creates a series of stress pulses that is transferred through the drill bit to the rock surface, and while the stress at the drill-bit tip/rock interface exceeds the compressive strength of the rock, it causes fractures that result in fragmentation of the rock. This facilitates augering and downward progress. In order to ensure that the drill-bit tip delivers the greatest effective impulse (the time integral of the drill-bit tip/rock pressure curve exceeding the strength of the rock), parameters such as the spring rates and the mass of the free mass, the drill bit and transducer have been varied and compared in both computer simulation and practical experiment. The most interesting findings and those of particular relevance to deep drilling indicate that increasing the mass of the drill bit has a limited (or even positive) influence on the rate of effective impulse delivered.

Application of Rosenbrock search technique to reduce the drilling cost of a well in Bai-Hassan oil field

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

Aswad, Z.A.R.; Al-Hadad, S.M.S.

1983-03-01

The powerful Rosenbrock search technique, which optimizes both the search directions using the Gram-Schmidt procedure and the step size using the Fibonacci line search method, has been used to optimize the drilling program of an oil well drilled in Bai-Hassan oil field in Kirkuk, Iran, using the twodimensional drilling model of Galle and Woods. This model shows the effect of the two major controllable variables, weight on bit and rotary speed, on the drilling rate, while considering other controllable variables such as the mud properties, hydrostatic pressure, hydraulic design, and bit selection. The effect of tooth dullness on the drillingmore » rate is also considered. Increasing the weight on the drill bit with a small increase or decrease in ratary speed resulted in a significant decrease in the drilling cost for most bit runs. It was found that a 48% reduction in this cost and a 97-hour savings in the total drilling time was possible under certain conditions.« less

Evaluation of the parameters affecting bone temperature during drilling using a three-dimensional dynamic elastoplastic finite element model.

PubMed

Chen, Yung-Chuan; Tu, Yuan-Kun; Zhuang, Jun-Yan; Tsai, Yi-Jung; Yen, Cheng-Yo; Hsiao, Chih-Kun

2017-11-01

A three-dimensional dynamic elastoplastic finite element model was constructed and experimentally validated and was used to investigate the parameters which influence bone temperature during drilling, including the drill speed, feeding force, drill bit diameter, and bone density. Results showed the proposed three-dimensional dynamic elastoplastic finite element model can effectively simulate the temperature elevation during bone drilling. The bone temperature rise decreased with an increase in feeding force and drill speed, however, increased with the diameter of drill bit or bone density. The temperature distribution is significantly affected by the drilling duration; a lower drilling speed reduced the exposure duration, decreases the region of the thermally affected zone. The constructed model could be applied for analyzing the influence parameters during bone drilling to reduce the risk of thermal necrosis. It may provide important information for the design of drill bits and surgical drilling powers.

Drill Bit Noise Illuminates the San Andreas Fault

NASA Astrophysics Data System (ADS)

Vasconcelos, Ivan; Snieder, Roel; Sava, Paul; Taylor, Tom; Malin, Peter; Chavarria, Andres

2008-09-01

Extracting the vibration response of the subsurface from noise is a rapidly growing field of research [Curtis et al., 2006; Larose et al., 2006]. We carried out broadside imaging of the San Andreas fault zone (SAFZ) using drill bit noise created in the main hole of the San Andreas Fault Observatory at Depth (SAFOD), near Parkfield, Calif. Imaging with drill bit noise is not new, but it traditionally requires the measurement of the vibrations of the drill stem [Rector and Marion, 1991]; such measurements provide the waves radiated by the drill bit. At SAFOD, these measurements were not available due to the absence of an accelerometer mounted on the drill stem. For this reason, the new technique of deconvolution interferometry was used [Vasconcelos and Snieder, 2008]. This technique extracts the waves propagating between seismometers from recordings of incoherent noise.

Investigating the effects of PDC cutters geometry on ROP using the Taguchi technique

NASA Astrophysics Data System (ADS)

Jamaludin, A. A.; Mehat, N. M.; Kamaruddin, S.

2017-10-01

At times, the polycrystalline diamond compact (PDC) bit’s performance dropped and affects the rate of penetration (ROP). The objective of this project is to investigate the effect of PDC cutter geometry and optimize them. An intensive study in cutter geometry would further enhance the ROP performance. The relatively extended analysis was carried out and four significant geometry factors have been identified that directly improved the ROP. Cutter size, back rake angle, side rake angle and chamfer angle are the stated geometry factors. An appropriate optimization technique that effectively controls all influential geometry factors during cutters manufacturing is introduced and adopted in this project. By adopting L9 Taguchi OA, simulation experiment is conducted by using explicit dynamics finite element analysis. Through a structure Taguchi analysis, ANOVA confirms that the most significant geometry to improve ROP is cutter size (99.16% percentage contribution). The optimized cutter is expected to drill with high ROP that can reduce the rig time, which in its turn, may reduce the total drilling cost.

Sample Acquisition and Caching architecture for the Mars Sample Return mission

NASA Astrophysics Data System (ADS)

Zacny, K.; Chu, P.; Cohen, J.; Paulsen, G.; Craft, J.; Szwarc, T.

This paper presents a Mars Sample Return (MSR) Sample Acquisition and Caching (SAC) study developed for the three rover platforms: MER, MER+, and MSL. The study took into account 26 SAC requirements provided by the NASA Mars Exploration Program Office. For this SAC architecture, the reduction of mission risk was chosen by us as having greater priority than mass or volume. For this reason, we selected a “ One Bit per Core” approach. The enabling technology for this architecture is Honeybee Robotics' “ eccentric tubes” core breakoff approach. The breakoff approach allows the drill bits to be relatively small in diameter and in turn lightweight. Hence, the bits could be returned to Earth with the cores inside them with only a modest increase to the total returned mass, but a significant decrease in complexity. Having dedicated bits allows a reduction in the number of core transfer steps and actuators. It also alleviates the bit life problem, eliminates cross contamination, and aids in hermetic sealing. An added advantage is faster drilling time, lower power, lower energy, and lower Weight on Bit (which reduces Arm preload requirements). Drill bits are based on the BigTooth bit concept, which allows re-use of the same bit multiple times, if necessary. The proposed SAC consists of a 1) Rotary-Percussive Core Drill, 2) Bit Storage Carousel, 3) Cache, 4) Robotic Arm, and 5) Rock Abrasion and Brushing Bit (RABBit), which is deployed using the Drill. The system also includes PreView bits (for viewing of cores prior to caching) and Powder bits for acquisition of regolith or cuttings. The SAC total system mass is less than 22 kg for MER and MER+ size rovers and less than 32 kg for the MSL-size rover.

New Rock-Drilling Method in 'Mars Yard' Test

NASA Image and Video Library

2017-10-23

This photo taken in the "Mars Yard" at NASA's Jet Propulsion Laboratory, Pasadena, California, on Aug. 1, 2017, shows a step in development of possible alternative techniques that NASA's Curiosity Mars rover might be able to use to resume drilling into rocks on Mars. In late 2016, after Curiosity's drill had collected sample material from 15 Martian rocks in four years, the drill's feed mechanism ceased working reliably. That motorized mechanism moved the bit forward or back with relation to stabilizer posts on either side of the bit. In normal drilling by Curiosity, the stabilizers were positioned on the target rock first, and then the feed mechanism extended the rotation-percussion bit into the rock. In the alternative technique seen here, called "feed-extended drilling," the test rover's stabilizers are not used to touch the rock. The bit is advanced into the rock by motion of the robotic arm rather than the drill's feed mechanism. https://photojournal.jpl.nasa.gov/catalog/PIA22062

Development of elastomeric isolators to reduce roof bolting machine drilling noise

PubMed Central

Michael, Robert; Yantek, David; Johnson, David; Ferro, Ernie; Swope, Chad

2015-01-01

Among underground coal miners, hearing loss remains one of the most common occupational illnesses. In response to this problem, the National Institute for Occupational Safety and Health (NIOSH) Office of Mine Safety and Health Research (OMSHR) conducts research to reduce the noise emission of underground coal-mining equipment, an example of which is a roof bolting machine. Field studies show that, on average, drilling noise is the most significant contributor to a roof bolting machine operator’s noise exposure. NIOSH OMSHR has determined that the drill steel and chuck are the dominant sources of drilling noise. NIOSH OMSHR, Corry Rubber Corporation, and Kennametal, Inc. have developed a bit isolator that breaks the steel-to-steel link between the drill bit and drill steel and a chuck isolator that breaks the mechanical connection between the drill steel and the chuck, thus reducing the noise radiated by the drill steel and chuck, and the noise exposure of the roof bolter operator. This paper documents the evolution of the bit isolator and chuck isolator including various alternative designs which may enhance performance. Laboratory testing confirms that production bit and chuck isolators reduce the A-weighted sound level generated during drilling by 3.7 to 6.6 dB. Finally, this paper summarizes results of a finite element analysis used to explore the key parameters of the drill bit isolator and chuck isolator to understand the impact these parameters have on noise. PMID:26568650

A novel drill design for photoacoustic guided surgeries

NASA Astrophysics Data System (ADS)

Shubert, Joshua; Lediju Bell, Muyinatu A.

2018-02-01

Fluoroscopy is currently the standard approach for image guidance of surgical drilling procedures. In addition to the harmful radiation dose to the patient and surgeon, fluoroscopy fails to visualize critical structures such as blood vessels and nerves within the drill path. Photoacoustic imaging is a well-suited imaging method to visualize these structures and it does not require harmful ionizing radiation. However, there is currently no clinical system available to deliver light to occluded drill bit tips. To address this challenge, a prototype drill was designed, built, and tested using an internal light delivery system that allows laser energy to be transferred from a stationary laser source to the tip of a spinning drill bit. Photoacoustic images were successfully obtained with the drill bit submerged in water and with the drill tip inserted into a thoracic vertebra from a human cadaver.

Accuracy study of computer-assisted drilling: the effect of bone density, drill bit characteristics, and use of a mechanical guide.

PubMed

Hüfner, T; Geerling, J; Oldag, G; Richter, M; Kfuri, M; Pohlemann, T; Krettek, C

2005-01-01

This study was designed to determine the clinical relevant accuracy of CT-based navigation for drilling. Experimental model. Laboratory. Twelve drills of varying lengths and diameters were tested with 2 different set-ups. Group 1 used free-hand navigated drilling technique with foam blocks equipped with titanium target points. Group 2 (control) used a newly developed 3-dimensional measurement device equipped with titanium target points with a fixed entry for the navigated drill to minimize bending forces. One examiner performed 690 navigated drillings using solely the monitor screen for control in both groups. The difference between the planned and the actual starting and target point (up to 150 mm distance) was measured (mm). Levene test and a nonpaired t test. Significance level was set as P < 0.05. The core accuracy of the navigation system measured with the 3-dimensional device was 0.5 mm. The mean distance from planned to actual entry points in group 1 was 1.3 (range, 0.6-3.4 mm). The mean distance between planned and actual target point was 3.4 (range, 1.7-5.8 mm). Free-hand navigated drilling showed an increased difference with increased length of the drill bits as well as with increased drilling channel for drill bits 2.5 and 3.2 mm and not for 3.5 and 4.5 mm (P < 0.05). The core accuracy of the navigation system is high. Compared with the navigated free-hand technique, the results suggest that drill bit deflection interferes directly with the precision. The precision is decreased when using small diameter and longer drill bits.

Mars Science Laboratory Drill

NASA Technical Reports Server (NTRS)

Okon, Avi B.; Brown, Kyle M.; McGrath, Paul L.; Klein, Kerry J.; Cady, Ian W.; Lin, Justin Y.; Ramirez, Frank E.; Haberland, Matt

2012-01-01

This drill (see Figure 1) is the primary sample acquisition element of the Mars Science Laboratory (MSL) that collects powdered samples from various types of rock (from clays to massive basalts) at depths up to 50 mm below the surface. A rotary-percussive sample acquisition device was developed with an emphasis on toughness and robustness to handle the harsh environment on Mars. It is the first rover-based sample acquisition device to be flight-qualified (see Figure 2). This drill features an autonomous tool change-out on a mobile robot, and novel voice-coil-based percussion. The drill comprises seven subelements. Starting at the end of the drill, there is a bit assembly that cuts the rock and collects the sample. Supporting the bit is a subassembly comprising a chuck mechanism to engage and release the new and worn bits, respectively, and a spindle mechanism to rotate the bit. Just aft of that is a percussion mechanism, which generates hammer blows to break the rock and create the dynamic environment used to flow the powdered sample. These components are mounted to a translation mechanism, which provides linear motion and senses weight-on-bit with a force sensor. There is a passive-contact sensor/stabilizer mechanism that secures the drill fs position on the rock surface, and flex harness management hardware to provide the power and signals to the translating components. The drill housing serves as the primary structure of the turret, to which the additional tools and instruments are attached. The drill bit assembly (DBA) is a passive device that is rotated and hammered in order to cut rock (i.e. science targets) and collect the cuttings (powder) in a sample chamber until ready for transfer to the CHIMRA (Collection and Handling for Interior Martian Rock Analysis). The DBA consists of a 5/8-in. (.1.6- cm) commercial hammer drill bit whose shank has been turned down and machined with deep flutes designed for aggressive cutting removal. Surrounding the shank of the bit is a thick-walled maraging steel collection tube allowing the powdered sample to be augured up the hole into the sample chamber. For robustness, the wall thickness of the DBA was maximized while still ensuring effective sample collection. There are four recesses in the bit tube that are used to retain the fresh bits in their bit box. The rotating bit is supported by a back-to-back duplex bearing pair within a housing that is connected to the outer DBA housing by two titanium diaphragms. The only bearings on the drill in the sample flow are protected by a spring-energized seal, and an integrated shield that diverts the ingested powdered sample from the moving interface. The DBA diaphragms provide radial constraint of the rotating bit and form the sample chambers. Between the diaphragms there is a sample exit tube from which the sample is transferred to the CHIMRA. To ensure that the entire collected sample is retained, no matter the orientation of the drill with respect to gravity during sampling, the pass-through from the forward to the aft chamber resides opposite to the exit tube.

Mechanical Coal-Face Fracturer

NASA Technical Reports Server (NTRS)

Collins, E. R., Jr.

1984-01-01

Radial points on proposed drill bit take advantage of natural fracture planes of coal. Radial fracture points retracted during drilling and impacted by piston to fracture coal once drilling halts. Group of bits attached to array of pneumatic drivers to fracture large areas of coal face.

Improved diamond coring bits developed for dry and chip-flush drilling

NASA Technical Reports Server (NTRS)

Decker, W. E.; Hampe, W. R.; Hampton, W. H.; Simon, A. B.

1971-01-01

Two rotary diamond bit designs, one operating with a chip-flushing fluid, the second including auger section to remove drilled chips, enhance usefulness of tool for exploratory and industrial core-drilling of hard, abrasive mineral deposits and structural masonry.

Counter-Rotating Tandem Motor Drilling System

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

Kent Perry

2009-04-30

Gas Technology Institute (GTI), in partnership with Dennis Tool Company (DTC), has worked to develop an advanced drill bit system to be used with microhole drilling assemblies. One of the main objectives of this project was to utilize new and existing coiled tubing and slimhole drilling technologies to develop Microhole Technology (MHT) so as to make significant reductions in the cost of E&P down to 5000 feet in wellbores as small as 3.5 inches in diameter. This new technology was developed to work toward the DOE's goal of enabling domestic shallow oil and gas wells to be drilled inexpensively comparedmore » to wells drilled utilizing conventional drilling practices. Overall drilling costs can be lowered by drilling a well as quickly as possible. For this reason, a high drilling rate of penetration is always desired. In general, high drilling rates of penetration (ROP) can be achieved by increasing the weight on bit and increasing the rotary speed of the bit. As the weight on bit is increased, the cutting inserts penetrate deeper into the rock, resulting in a deeper depth of cut. As the depth of cut increases, the amount of torque required to turn the bit also increases. The Counter-Rotating Tandem Motor Drilling System (CRTMDS) was planned to achieve high rate of penetration (ROP) resulting in the reduction of the drilling cost. The system includes two counter-rotating cutter systems to reduce or eliminate the reactive torque the drillpipe or coiled tubing must resist. This would allow the application of maximum weight-on-bit and rotational velocities that a coiled tubing drilling unit is capable of delivering. Several variations of the CRTDMS were designed, manufactured and tested. The original tests failed leading to design modifications. Two versions of the modified system were tested and showed that the concept is both positive and practical; however, the tests showed that for the system to be robust and durable, borehole diameter should be substantially larger than that of slim holes. As a result, the research team decided to complete the project, document the tested designs and seek further support for the concept outside of the DOE.« less

Powder-Collection System for Ultrasonic/Sonic Drill/Corer

NASA Technical Reports Server (NTRS)

Sherrit, Stewart; Bar-Cohen, Yoseph; Bao, Xiaoqi; Chang, Zensheu; Blake, David; Bryson, Charles

2005-01-01

A system for collecting samples of powdered rock has been devised for use in conjunction with an ultrasonic/sonic drill/corer (USDC) -- a lightweight, lowpower apparatus designed to cut into, and acquire samples of, rock or other hard material for scientific analysis. The USDC includes a drill bit, corer, or other tool bit, in which ultrasonic and sonic vibrations are excited by an electronically driven piezoelectric actuator. The USDC advances into the rock or other material of interest by means of a hammering action and a resulting chiseling action at the tip of the tool bit. The hammering and chiseling actions are so effective that unlike in conventional twist drilling, a negligible amount of axial force is needed to make the USDC advance into the material. Also unlike a conventional twist drill, the USDC operates without need for torsional restraint, lubricant, or a sharp bit. The USDC generates powder as a byproduct of the drilling or coring process. The purpose served by the present samplecollection system is to remove the powder from the tool-bit/rock interface and deliver the powder to one or more designated location(s) for analysis or storage

High-velocity frictional strength across the Tohoku-Oki megathrust determined from surface drilling torque

NASA Astrophysics Data System (ADS)

Ujiie, K.; Inoue, T.; Ishiwata, J.

2015-12-01

Frictional strength at seismic slip rates is a key to evaluate fault weakening and rupture propagation during earthquakes. The Japan Trench First Drilling Project (JFAST) drilled through the shallow plate-boundary thrust, where huge displacements of ~50 m occurred during the 2011 Tohoku-Oki earthquake. To determine the downhole frictional strength at drilled site (Site C0019), we analyzed surface drilling data. The equivalent slip rate estimated from the rotation rate and inner and outer radiuses of the drill bit ranges from 0.8 to 1.3 m/s. The measured torque includes the frictional torque between the drilling string and borehole wall, the viscous torque between the drilling string and seawater/drilling fluid, and the drilling torque between the drill bit and sediments. We subtracted the former two from the measured torque using the torque data during bottom-up rotating operations at several depths. Then, the shear stress was calculated from the drilling torque taking the configuration of the drill bit into consideration. The normal stress was estimated from the weight on bit data and the projected area of the drill bit. Assuming negligible cohesion, the frictional strength was obtained by dividing shear stress by normal stress. The results show a clear contrast in high-velocity frictional strength across the plate-boundary thrust: the friction coefficient of frontal prism sediments (hemipelagic mudstones) in hanging wall is 0.1-0.2, while that in subducting sediments (hemipelagic to pelagic mudstones and chert) in footwall increases to 0.2-0.4. The friction coefficient of smectite-rich pelagic clay in the plate-boundary thrust is ~0.1, which is consistent with that obtained from high-velocity (1.3 m/s) friction experiments and temperature measurements. We conclude that surface drilling torque provides useful data to obtain a continuous downhole frictional strength.

High power laser-mechanical drilling bit and methods of use

DOEpatents

Grubb, Daryl L.; Kolachalam, Sharath K.; Faircloth, Brian O.; Rinzler, Charles C.; Allen, Erik C.; Underwood, Lance D.; Zediker, Mark S.

2017-02-07

An apparatus with a high power laser-mechanical bit for use with a laser drilling system and a method for advancing a borehole. The laser-mechanical bit has a beam path and mechanical removal devices that provide for the removal of laser-affected rock to advance a borehole.

Drill Bit Tip on Mars Rover Curiosity, Side View

NASA Image and Video Library

2013-02-04

The shape of the tip of the bit in the drill of NASA Mars rover Curiosity is apparent in this view recorded by the remote micro-imager in the rover ChemCam instrument on Mars. Jan. 29, 2012; the bit is about 0.6 inch 1.6 centimeters wide.

Rotary steerable motor system for underground drilling

DOEpatents

Turner, William E.; Perry, Carl A.; Wassell, Mark E.; Barbely, Jason R.; Burgess, Daniel E.; Cobern, Martin E.

2010-07-27

A preferred embodiment of a system for rotating and guiding a drill bit in an underground bore includes a drilling motor and a drive shaft coupled to drilling motor so that drill bit can be rotated by the drilling motor. The system further includes a guidance module having an actuating arm movable between an extended position wherein the actuating arm can contact a surface of the bore and thereby exert a force on the housing of the guidance module, and a retracted position.

Rotary steerable motor system for underground drilling

DOEpatents

Turner, William E [Durham, CT; Perry, Carl A [Middletown, CT; Wassell, Mark E [Kingwood, TX; Barbely, Jason R [Middletown, CT; Burgess, Daniel E [Middletown, CT; Cobern, Martin E [Cheshire, CT

2008-06-24

A preferred embodiment of a system for rotating and guiding a drill bit in an underground bore includes a drilling motor and a drive shaft coupled to drilling motor so that drill bit can be rotated by the drilling motor. The system further includes a guidance module having an actuating arm movable between an extended position wherein the actuating arm can contact a surface of the bore and thereby exert a force on the housing of the guidance module, and a retracted position.

Ultrasonic/Sonic Rotary-Hammer Drills

NASA Technical Reports Server (NTRS)

Badescu, Mircea; Sherrit, Stewart; Bar-Cohen, Yoseph; Bao, Xiaoqi; Kassab, Steve

2010-01-01

Ultrasonic/sonic rotary-hammer drill (USRoHD) is a recent addition to the collection of apparatuses based on ultrasonic/sonic drill corer (USDC). As described below, the USRoHD has several features, not present in a basic USDC, that increase efficiency and provide some redundancy against partial failure. USDCs and related apparatuses were conceived for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. They have been described in numerous previous NASA Tech Briefs articles. To recapitulate: A USDC can be characterized as a lightweight, lowpower, piezoelectrically driven jackhammer in which ultrasonic and sonic vibrations are generated and coupled to a tool bit. A basic USDC includes a piezoelectric stack, an ultrasonic transducer horn connected to the stack, a free mass ( free in the sense that it can bounce axially a short distance between hard stops on the horn and the bit), and a tool bit. The piezoelectric stack creates ultrasonic vibrations that are mechanically amplified by the horn. The bouncing of the free mass between the hard stops generates the sonic vibrations. The combination of ultrasonic and sonic vibrations gives rise to a hammering action (and a resulting chiseling action at the tip of the tool bit) that is more effective for drilling than is the microhammering action of ultrasonic vibrations alone. The hammering and chiseling actions are so effective that unlike in conventional twist drilling, little applied axial force is needed to make the apparatus advance into the material of interest. There are numerous potential applications for USDCs and related apparatuses in geological exploration on Earth and on remote planets. In early USDC experiments, it was observed that accumulation of cuttings in a drilled hole causes the rate of penetration of the USDC to decrease steeply with depth, and that the rate of penetration can be increased by removing the cuttings. The USRoHD concept provides for removal of cuttings in the same manner as that of a twist drill: An USRoHD includes a USDC and a motor with gearhead (see figure). The USDC provides the bit hammering and the motor provides the bit rotation. Like a twist drill bit, the shank of the tool bit of the USRoHD is fluted. As in the operation of a twist drill, the rotation of the fluted drill bit removes cuttings from the drilled hole. The USRoHD tool bit is tipped with a replaceable crown having cutting teeth on its front surface. The teeth are shaped to promote fracturing of the rock face through a combination of hammering and rotation of the tool bit. Helical channels on the outer cylindrical surface of the crown serve as a continuation of the fluted surface of the shank, helping to remove cuttings. In the event of a failure of the USDC, the USRoHD can continue to operate with reduced efficiency as a twist drill. Similarly, in the event of a failure of the gearmotor, the USRoHD can continue to operate with reduced efficiency as a USDC.

Optimization of Mud Hammer Drilling Performance--A Program to Benchmark the Viability of Advanced Mud Hammer Drilling

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

Arnis Judzis

2006-03-01

Operators continue to look for ways to improve hard rock drilling performance through emerging technologies. A consortium of Department of Energy, operator and industry participants put together an effort to test and optimize mud driven fluid hammers as one emerging technology that has shown promise to increase penetration rates in hard rock. The thrust of this program has been to test and record the performance of fluid hammers in full scale test conditions including, hard formations at simulated depth, high density/high solids drilling muds, and realistic fluid power levels. This paper details the testing and results of testing two 7more » 3/4 inch diameter mud hammers with 8 1/2 inch hammer bits. A Novatek MHN5 and an SDS Digger FH185 mud hammer were tested with several bit types, with performance being compared to a conventional (IADC Code 537) tricone bit. These tools functionally operated in all of the simulated downhole environments. The performance was in the range of the baseline ticone or better at lower borehole pressures, but at higher borehole pressures the performance was in the lower range or below that of the baseline tricone bit. A new drilling mode was observed, while operating the MHN5 mud hammer. This mode was noticed as the weight on bit (WOB) was in transition from low to high applied load. During this new ''transition drilling mode'', performance was substantially improved and in some cases outperformed the tricone bit. Improvements were noted for the SDS tool while drilling with a more aggressive bit design. Future work includes the optimization of these or the next generation tools for operating in higher density and higher borehole pressure conditions and improving bit design and technology based on the knowledge gained from this test program.« less

Acoustic Emission Measurements for Tool Wear Evaluation in Drilling

NASA Astrophysics Data System (ADS)

Gómez, Martín P.; Migliori, Julio; Ruzzante, José E.; D'Attellis, Carlos E.

2009-03-01

In this work, the tool condition in a drilling process of SAE 1040 steel samples was studied by means of acoustic emission. The studied drill bits were modified with artificial and real failures, such as different degrees of wear in the cutting edge and in the outer corner. Some correlation between mean power of the acoustic emission parameters and the drill bit wear condition was found.

Recent performance of the dual-resistivity MWD tool

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

Wagstaff, J.D.; Grupping, T.I.F.

1990-06-01

This article reports on the dual-resistivity MWD tool, which uses section of the drill collar as electrodes and provides two independent resistivity measurements: a principal well-focused lateral measurement of the current flowing radially from a defined segment of the drill collar and a secondary axial or bit measurement of the current flowing from a defined portion of the lower bottomhole assembly (BHA). In oil-based muds, a single (bit) measurement is made of the current flowing to the formation through the drill bit.

Single Piezo-Actuator Rotary-Hammering Drill

NASA Technical Reports Server (NTRS)

Sherrit, Stewart; Bao, Xiaoqi; Badescu, Mircea; Bar-Cohen, Yoseph

2011-01-01

This innovation comprises a compact drill that uses low-axial preload, via vibrations, that fractures the rock under the bit kerf, and rotates the bit to remove the powdered cuttings while augmenting the rock fracture via shear forces. The vibrations fluidize the powered cuttings inside the flutes around the bit, reducing the friction with the auger surface. These combined actions reduce the consumed power and the heating of the drilled medium, helping to preserve the pristine content of the produced samples. The drill consists of an actuator that simultaneously impacts and rotates the bit by applying force and torque via a single piezoelectric stack actuator without the need for a gearbox or lever mechanism. This reduces the development/fabrication cost and complexity. The piezoelectric actuator impacts the surface and generates shear forces, fragmenting the drilled medium directly under the bit kerf by exceeding the tensile and/or shear strength of the struck surface. The percussive impact action of the actuator leads to penetration of the medium by producing a zone of finely crushed rock directly underneath the struck location. This fracturing process is highly enhanced by the shear forces from the rotation and twisting action. To remove the formed cuttings, the bit is constructed with an auger on its internal or external surface. One of the problems with pure hammering is that, as the teeth become embedded in the sample, the drilling efficiency drops unless the teeth are moved away from the specific footprint location. By rotating the teeth, they are moved to areas that were not fragmented, and thus the rock fracturing is enhanced via shear forces. The shear motion creates ripping or chiseling action to produce larger fragments to increase the drilling efficiency, and to reduce the required power. The actuator of the drill consists of a piezoelectric stack that vibrates the horn. The stack is compressed by a bolt between the backing and the horn in order to prevent it from being subjected to tensile stress that will cause it to fail. The backing is intended to transfer the generated mechanical vibrations towards the horn. In order to cause rotation, the horn is configured asymmetrically with helical segments and, upon impacting the bit, it introduces longitudinal along the axis of the actuator and tangential force causing twisting action that rotates the bit. The longitudinal component of the vibrations of the stack introduces percussion impulses between the bit and the rock to fracture it when the ultimate strain is exceeded under the bit.

Effects of drilling parameters in numerical simulation to the bone temperature elevation

NASA Astrophysics Data System (ADS)

Akhbar, Mohd Faizal Ali; Malik, Mukhtar; Yusoff, Ahmad Razlan

2018-04-01

Drilling into the bone can produce significant amount of heat which can cause bone necrosis. Understanding the drilling parameters influence to the heat generation is necessary to prevent thermal necrosis to the bone. The aim of this study is to investigate the influence of drilling parameters on bone temperature elevation. Drilling simulations of various combinations of drill bit diameter, rotational speed and feed rate were performed using finite element software DEFORM-3D. Full-factorial design of experiments (DOE) and two way analysis of variance (ANOVA) were utilised to examine the effect of drilling parameters and their interaction influence on the bone temperature. The maximum bone temperature elevation of 58% was demonstrated within the range in this study. Feed rate was found to be the main parameter to influence the bone temperature elevation during the drilling process followed by drill diameter and rotational speed. The interaction between drill bit diameter and feed rate was found to be significantly influence the bone temperature. It is discovered that the use of low rotational speed, small drill bit diameter and high feed rate are able to minimize the elevation of bone temperature for safer surgical operations.

Development of a Tool Condition Monitoring System for Impregnated Diamond Bits in Rock Drilling Applications

NASA Astrophysics Data System (ADS)

Perez, Santiago; Karakus, Murat; Pellet, Frederic

2017-05-01

The great success and widespread use of impregnated diamond (ID) bits are due to their self-sharpening mechanism, which consists of a constant renewal of diamonds acting at the cutting face as the bit wears out. It is therefore important to keep this mechanism acting throughout the lifespan of the bit. Nonetheless, such a mechanism can be altered by the blunting of the bit that ultimately leads to a less than optimal drilling performance. For this reason, this paper aims at investigating the applicability of artificial intelligence-based techniques in order to monitor tool condition of ID bits, i.e. sharp or blunt, under laboratory conditions. Accordingly, topologically invariant tests are carried out with sharp and blunt bits conditions while recording acoustic emissions (AE) and measuring-while-drilling variables. The combined output of acoustic emission root-mean-square value (AErms), depth of cut ( d), torque (tob) and weight-on-bit (wob) is then utilized to create two approaches in order to predict the wear state condition of the bits. One approach is based on the combination of the aforementioned variables and another on the specific energy of drilling. The two different approaches are assessed for classification performance with various pattern recognition algorithms, such as simple trees, support vector machines, k-nearest neighbour, boosted trees and artificial neural networks. In general, Acceptable pattern recognition rates were obtained, although the subset composed by AErms and tob excels due to the high classification performances rates and fewer input variables.

Temperature changes and chondrocyte death during drilling in a bovine cartilage model and chondroprotection by modified irrigation solutions.

PubMed

Farhan-Alanie, Muhamed M H; Hall, Andrew C

2014-11-01

Drilling into cartilage/bone is often required for orthopaedic surgery. While drilling into bone has been studied, the response of cartilage has received little attention. We have measured cartilage and drill bit temperatures during drilling and quantified the zone of chondrocyte death (ZCD) around the hole in the presence/absence of irrigation solutions. Drilling was performed using a 1.5-mm orthopaedic drill bit applied to bovine metatarsophalangeal joints and temperatures recorded by infrared camera. Osteochondral explants were then incubated with 5-chloromethylfluorescein diacetate (CMFDA) and propidium iodide (PI) to label living/dead chondrocytes respectively. The width of the ZCD was quantified by confocal laser scanning microscopy (CLSM) and image analysis. Without irrigation, the ZCD following drilling for two seconds was 135 ± 15 μm and this increased (>fourfold, P < 0.001) with five seconds of drilling. Irrigation reduced the ZCD following drilling for both two and five seconds (P < 0.05, P < 0.001 respectively) to the same level (approx. 60 μm). Without irrigation, drill bit and cartilage temperature increased rapidly to >265 and 119 °C respectively, whereas the camera saturated at >282 °C during drilling for five seconds. With irrigation, the drill bit temperature was significantly reduced during drilling for two and five seconds (approx. 90 °C) with negligible change in cartilage temperature. Drilling while irrigating with hyperosmotic saline (600 mOsm) reduced (P < 0.01) the ZCD compared to saline, whereas chondrocyte death was increased (P < 0.01) by Ca(2+) saline (5 mM). Reducing temperature during drilling by irrigation markedly suppressed, but did not abolish chondrocyte death. Optimising the irrigation solution by raising osmolarity and reducing Ca(2+) content significantly reduced chondrocyte death during drilling and may be clinically beneficial.

Influence of Drilling Parameters on Torque during Drilling of GFRP Composites Using Response Surface Methodology

NASA Astrophysics Data System (ADS)

Mohan, N. S.; Kulkarni, S. M.

2018-01-01

Polymer based composites have marked their valuable presence in the area of aerospace, defense and automotive industry. Components made of composite, are assembled to main structure by fastener, which require accurate, precise high quality holes to be drilled. Drilling the hole in composite with accuracy require control over various processes parameters viz., speed, feed, drill bit size and thickens of specimen. TRIAC VMC machining center is used to drill the hole and to relate the cutting and machining parameters on the torque. MINITAB 14 software is used to analyze the collected data. As a function of cutting and specimen parameters this method could be useful for predicting torque parameters. The purpose of this work is to investigate the effect of drilling parameters to get low torque value. Results show that thickness of specimen and drill bit size are significant parameters influencing the torque and spindle speed and feed rate have least influence and overlaid plot indicates a feasible and low region of torque is observed for medium to large sized drill bits for the range of spindle speed selected. Response surface contour plots indicate the sensitivity of the drill size and specimen thickness to the torque.

Drill Bit Tip on Mars Rover Curiosity, Head-on View

NASA Image and Video Library

2013-02-04

This head-on view shows the tip of the drill bit on NASA Mars rover Curiosity. The view merges two exposures taken by the remote micro-imager in the rover ChemCam instrument at different focus settings.

Deposition and characterization of TiAlSiN nanocomposite coatings prepared by reactive pulsed direct current unbalanced magnetron sputtering

NASA Astrophysics Data System (ADS)

Barshilia, Harish C.; Ghosh, Moumita; Shashidhara; Ramakrishna, Raja; Rajam, K. S.

2010-08-01

This work reports the performance of high speed steel drill bits coated with TiAlSiN nanocomposite coating at different Si contents (5.5-8.1 at.%) prepared using a four-cathode reactive pulsed direct current unbalanced magnetron sputtering system. The surface morphology of the as-deposited coatings was characterized using field emission scanning electron microscopy. The crystallographic structure, chemical composition and bonding structure were evaluated using X-ray diffraction, energy-dispersive X-ray analysis, X-ray photoelectron spectroscopy, respectively. The corrosion behavior, mechanical properties and thermal stability of TiAlSiN nanocomposite coatings were also studied using potentiodynamic polarization, nanoindentation and Raman spectroscopy, respectively. The TiAlSiN coating thickness was approximately 2.5-2.9 μm. These coatings exhibited a maximum hardness of 38 GPa at a silicon content of approximately 6.9 at.% and were stable in air up to 850 °C. For the performance evaluation, the TiAlSiN coated drills were tested under accelerated machining conditions by drilling a 12 mm thick 304 stainless steel plate. Under dry conditions the uncoated drill bits failed after drilling 50 holes, whereas, TiAlSiN coated drill bits (Si = 5.5 at.%) drilled 714 holes before failure. Results indicated that for TiAlSiN coated drill bits the tool life increased by a factor of more than 14.

Study on drilling induced delamination of woven kenaf fiber reinforced epoxy composite using carbide drills

NASA Astrophysics Data System (ADS)

Suhaily, M.; Hassan, C. H. Che; Jaharah, A. G.; Azmi, H.; Afifah, M. A.; Khairusshima, M. K. Nor

2018-04-01

In this research study, it presents the influences of drilling parameters on the delamination factor during the drilling of woven kenaf fiber reinforced epoxy composite laminates when using the carbide drill bits. The purpose of this study is to investigate the influence of drilling parameters such as cutting speed, feed rate and drill sizes on the delamination produced when drilling woven kenaf reinforced epoxy composite using the non-coated carbide drill bits. The damage generated on the woven kenaf reinforced epoxy composite laminates were observed both at the entrance and exit surface during the drilling operation. The experiments were conducted according to the Box Behnken experimental designs. The results indicated that the drill diameter has a significant influence on the delamination when drilling the woven kenaf fiber reinforced epoxy composites.

About creation of machines for rock destruction with formation of apertures of various cross-sections

NASA Astrophysics Data System (ADS)

Zhukov, I. A.; Dvornikov, L. T.; Nikitenko, S. M.

2016-04-01

The article presents the results of the experimental research of the high strength rock destruction by a bladeless tool. Rational circuit designs of disposing of indenters in the impact part of the drill bits and a diamond tool are justified. New constructive solutions of reinforcing bladeless drill bits, which allow drilling blast-holes of the various cross-section, are shown.

Self-Advancing Step-Tap Drills

NASA Technical Reports Server (NTRS)

Pettit, Donald R.; Camarda, Charles J.; Penner, Ronald K.; Franklin, Larry D.

2007-01-01

Self-advancing tool bits that are hybrids of drills and stepped taps make it possible to form threaded holes wider than about 1/2 in. (about 13 mm) without applying any more axial force than is necessary for forming narrower pilot holes. These self-advancing stepped-tap drills were invented for use by space-suited astronauts performing repairs on reinforced carbon/carbon space-shuttle leading edges during space walks, in which the ability to apply axial drilling forces is severely limited. Self-advancing stepped-tap drills could also be used on Earth for making wide holes without applying large axial forces. A self-advancing stepped-tap drill (see figure) includes several sections having progressively larger diameters, typically in increments between 0.030 and 0.060 in. (between about 0.8 and about 1.5 mm). The tip section, which is the narrowest, is a pilot drill bit that typically has a diameter between 1/8 and 3/16 in. (between about 3.2 and about 4.8 mm). The length of the pilot-drill section is chosen, according to the thickness of the object to be drilled and tapped, so that the pilot hole is completed before engagement of the first tap section. Provided that the cutting-edge geometry of the drill bit is optimized for the material to be drilled, only a relatively small axial force [typically of the order of a few pounds (of the order of 10 newtons)] must be applied during drilling of the pilot hole. Once the first tap section engages the pilot hole, it is no longer necessary for the drill operator to apply axial force: the thread engagement between the tap and the workpiece provides the axial force to advance the tool bit. Like the pilot-drill section, each tap section must be long enough to complete its hole before engagement of the next, slightly wider tap section. The precise values of the increments in diameter, the thread pitch, the rake angle of the tap cutting edge, and other geometric parameters of the tap sections must be chosen, in consideration of the workpiece material and thickness, to prevent stripping of threads during the drilling/tapping operation. A stop-lip or shoulder at the shank end of the widest tap section prevents further passage of the tool bit through the hole.

Rock bit requires no flushing medium to maintain drilling speed

NASA Technical Reports Server (NTRS)

1965-01-01

Steel drill bit having terraces of teeth intersected by spiral grooves with teeth permits the boring of small holes through rock with low power. The cuttings are stored in a chamber behind the cutting head. Could be used as sampling device.

Percussive Augmenter of Rotary Drills (PARoD)

NASA Technical Reports Server (NTRS)

Badescu, Mircea; Hasenoehrl, Jennifer; Bar-Cohen, Yoseph; Sherrit, Stewart; Bao, Xiaoqi; Chang, Zensheu; Ostlund, Patrick; Aldrich, Jack

2013-01-01

Increasingly, NASA exploration mission objectives include sample acquisition tasks for in-situ analysis or for potential sample return to Earth. To address the requirements for samplers that could be operated at the conditions of the various bodies in the solar system, a piezoelectric actuated percussive sampling device was developed that requires low preload (as low as 10 N) which is important for operation at low gravity. This device can be made as light as 400 g, can be operated using low average power, and can drill rocks as hard as basalt. Significant improvement of the penetration rate was achieved by augmenting the hammering action by rotation and use of a fluted bit to provide effective cuttings removal. Generally, hammering is effective in fracturing drilled media while rotation of fluted bits is effective in cuttings removal. To benefit from these two actions, a novel configuration of a percussive mechanism was developed to produce an augmenter of rotary drills. The device was called Percussive Augmenter of Rotary Drills (PARoD). A breadboard PARoD was developed with a 6.4 mm (0.25 in) diameter bit and was demonstrated to increase the drilling rate of rotation alone by 1.5 to over 10 times. The test results of this configuration were published in a previous publication. Further, a larger PARoD breadboard with a 50.8 mm (2.0 in) diameter bit was developed and tested. This paper presents the design, analysis and test results of the large diameter bit percussive augmenter.

Optimization of Operating Parameters for Minimum Mechanical Specific Energy in Drilling

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

Hamrick, Todd

2011-01-01

Efficiency in drilling is measured by Mechanical Specific Energy (MSE). MSE is the measure of the amount of energy input required to remove a unit volume of rock, expressed in units of energy input divided by volume removed. It can be expressed mathematically in terms of controllable parameters; Weight on Bit, Torque, Rate of Penetration, and RPM. It is well documented that minimizing MSE by optimizing controllable factors results in maximum Rate of Penetration. Current methods for computing MSE make it possible to minimize MSE in the field only through a trial-and-error process. This work makes it possible to computemore » the optimum drilling parameters that result in minimum MSE. The parameters that have been traditionally used to compute MSE are interdependent. Mathematical relationships between the parameters were established, and the conventional MSE equation was rewritten in terms of a single parameter, Weight on Bit, establishing a form that can be minimized mathematically. Once the optimum Weight on Bit was determined, the interdependent relationship that Weight on Bit has with Torque and Penetration per Revolution was used to determine optimum values for those parameters for a given drilling situation. The improved method was validated through laboratory experimentation and analysis of published data. Two rock types were subjected to four treatments each, and drilled in a controlled laboratory environment. The method was applied in each case, and the optimum parameters for minimum MSE were computed. The method demonstrated an accurate means to determine optimum drilling parameters of Weight on Bit, Torque, and Penetration per Revolution. A unique application of micro-cracking is also presented, which demonstrates that rock failure ahead of the bit is related to axial force more than to rotation speed.« less

Numerical Simulation of Bottomhole Flow Field Structure in Particle Impact Drilling

NASA Astrophysics Data System (ADS)

Zhou, Weidong; Huang, Jinsong; Li, Luopeng

2018-01-01

In order to quantitatively describe the flow field distribution of the PID drilling bit in the bottomhole working condition, the influence of the fluid properties (pressure and viscosity) on the flow field of the bottom hole and the erosion and wear law of the drill body are compared. The flow field model of the eight - inch semi - vertical borehole drilling bit was established by CFX software. The working state of the jet was returned from the inlet of the drill bit to the nozzle outlet and flowed out at the bottom of the nozzle. The results show that there are irregular three-dimensional motion of collision and bounce after the jetting, resulting in partial impact on the drill body and causing impact and damage to the cutting teeth. The jet of particles emitted by different nozzles interfere with each other and affect the the bottom of the impact pressure; reasonable nozzle position can effectively reduce these interference.

Effects of specialized drill bits on hole defects of CFRP laminates

NASA Astrophysics Data System (ADS)

Li, Chao; Xu, Jinyang; Chen, Ming

2018-05-01

Drilling is a conventional machining process widely applied to carbon fiber reinforced plastics (CFRP) for the riveting and fastening purposes in the aerospace and automotive industries. However, the machining mechanism of CFRP composites differ significantly from that of homogeneous metal alloys owing to their prominent anisotropy and heterogeneity. Serious hole defects such as fiber pullout, matrix debonding and delamination are generally produced during the hole-making process, resulting in the poor machined surface quality, low fatigue durability or even the part rejections. In order to minimize the defects especially the delamination damage in composites drilling, specialized drill bits are often a primary choice being widely adopted in a real production. This paper aims to study the effects of two drills differing in geometrical characteristics during the drilling of CFRP laminates. A number of drilling experiments were carried out with the aim to evaluate the drilling performance of different drill bits. A scanning electron microscope (SEM) was used to observe the drilled surfaces to study the surface roughness. A high frequency scanning acoustic microscope (SAM) was applied to characterize the drilled hole morphologies with a particular focus on the delamination damage occurring in the CFRP laminates. The obtained results indicate that the fiber orientation relative to the cutting direction is a key factor affecting hole morphology and hole wall defects can be reduced by utilizing specialized drill geometries. Moreover, the dagger drill was confirmed outperforming the brad spur drill from the aspect of reducing drilling-induced delamination.

Drilling and Caching Architecture for the Mars2020 Mission

NASA Astrophysics Data System (ADS)

Zacny, K.

2013-12-01

We present a Sample Acquisition and Caching (SAC) architecture for the Mars2020 mission and detail how the architecture meets the sampling requirements described in the Mars2020 Science Definition Team (SDT) report. The architecture uses 'One Bit per Core' approach. Having dedicated bit for each rock core allows a reduction in the number of core transfer steps and actuators and this reduces overall mission risk. It also alleviates the bit life problem, eliminates cross contamination, and aids in hermetic sealing. An added advantage is faster drilling time, lower power, lower energy, and lower Weight on Bit (which reduces Arm preload requirements). To enable replacing of core samples, the drill bits are based on the BigTooth bit design. The BigTooth bit cuts a core diameter slightly smaller than the imaginary hole inscribed by the inner surfaces of the bits. Hence the rock core could be much easier ejected along the gravity vector. The architecture also has three additional types of bits that allow analysis of rocks. Rock Abrasion and Brushing Bit (RABBit) allows brushing and grinding of rocks in the same was as Rock Abrasion Tool does on MER. PreView bit allows viewing and analysis of rock core surfaces. Powder and Regolith Acquisition Bit (PRABit) captures regolith and rock powder either for in situ analysis or sample return. PRABit also allows sieving capabilities. The architecture can be viewed here: http://www.youtube.com/watch?v=_-hOO4-zDtE

Testing of the Prototype Mars Drill and Sample Acquisition System in the Mars Analog Site of the Antarctica's Dry Valleys

NASA Astrophysics Data System (ADS)

Zacny, K.; Paulsen, G.; McKay, C.; Glass, B. J.; Marinova, M.; Davila, A. F.; Pollard, W. H.; Jackson, A.

2011-12-01

We report on the testing of the one meter class prototype Mars drill and cuttings sampling system, called the IceBreaker in the Dry Valleys of Antarctica. The drill consists of a rotary-percussive drill head, a sampling auger with a bit at the end having an integrated temperature sensor, a Z-stage for advancing the auger into the ground, and a sampling station for moving the augered ice shavings or soil cuttings into a sample cup. In November/December of 2010, the IceBreaker drill was tested in the Uni-versity Valley (within the Beacon Valley region of the Antarctic Dry Valleys). University Valley is a good analog to the Northern Polar Regions of Mars because a layer of dry soil lies on top of either ice-cemeted ground or massive ice (depending on the location within the valley). That is exactly what the 2007 Phoenix mission discovered on Mars. The drill demonstrated drilling in ice-cemented ground and in massive ice at the 1-1-100-100 level; that is the drill reached 1 meter in 1 hour with 100 Watts of power and 100 Newton Weight on Bit. This corresponds to an average energy of 100 Whr. At the same time, the bit temperature measured by the bit thermocouple did not exceed more than 10 °C above the formation temperature. The temperature also never exceeded freezing, which minimizes chances of getting stuck and also of altering the materials that are being sampled and analyzed. The samples in the forms of cuttings were acquired every 10 cm intervals into sterile bags. These tests have shown that drilling on Mars, in ice cemented ground with limited power, energy and Weight on Bit, and collecting samples in discrete depth intervals is possible within the given mass, power, and energy levels of a Phoenix-size lander and within the duration of a Phoenix-like mission.

Smaller Footprint Drilling System for Deep and Hard Rock Environments; Feasibility of Ultra-High-Speed Diamond Drilling

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

Arnis Judzis; Alan Black; Homer Robertson

2006-03-01

The two phase program addresses long-term developments in deep well and hard rock drilling. TerraTek believes that significant improvements in drilling deep hard rock will be obtained by applying ultra-high rotational speeds (greater than 10,000 rpm). The work includes a feasibility of concept research effort aimed at development that will ultimately result in the ability to reliably drill ''faster and deeper'' possibly with smaller, more mobile rigs. The principle focus is on demonstration testing of diamond bits rotating at speeds in excess of 10,000 rpm to achieve high rate of penetration (ROP) rock cutting with substantially lower inputs of energymore » and loads. The significance of the ultra-high rotary speed drilling system is the ability to drill into rock at very low weights on bit and possibly lower energy levels. The drilling and coring industry today does not practice this technology. The highest rotary speed systems in oil field and mining drilling and coring today run less than 10,000 rpm--usually well below 5,000 rpm. This document details the progress to date on the program entitled ''Smaller Footprint Drilling System for Deep and Hard Rock Environments: Feasibility of Ultra-High-Speed Diamond Drilling'' for the period starting 1 October 2004 through 30 September 2005. Additionally, research activity from 1 October 2005 through 28 February 2006 is included in this report: (1) TerraTek reviewed applicable literature and documentation and convened a project kick-off meeting with Industry Advisors in attendance. (2) TerraTek designed and planned Phase I bench scale experiments. Some difficulties continue in obtaining ultra-high speed motors. Improvements have been made to the loading mechanism and the rotational speed monitoring instrumentation. New drill bit designs have been provided to vendors for production. A more consistent product is required to minimize the differences in bit performance. A test matrix for the final core bit testing program has been completed. (3) TerraTek is progressing through Task 3 ''Small-scale cutting performance tests''. (4) Significant testing has been performed on nine different rocks. (5) Bit balling has been observed on some rock and seems to be more pronounces at higher rotational speeds. (6) Preliminary analysis of data has been completed and indicates that decreased specific energy is required as the rotational speed increases (Task 4). This data analysis has been used to direct the efforts of the final testing for Phase I (Task 5). (7) Technology transfer (Task 6) has begun with technical presentations to the industry (see Judzis).« less

Can a surgeon drill accurately at a specified angle?

PubMed Central

Brioschi, Valentina; Cook, Jodie; Arthurs, Gareth I

2016-01-01

Objectives To investigate whether a surgeon can drill accurately a specified angle and whether surgeon experience, task repetition, drill bit size and perceived difficulty influence drilling angle accuracy. Methods The sample population consisted of final-year students (n=25), non-specialist veterinarians (n=22) and board-certified orthopaedic surgeons (n=8). Each participant drilled a hole twice in a horizontal oak plank at 30°, 45°, 60°, 80°, 85° and 90° angles with either a 2.5  or a 3.5 mm drill bit. Participants then rated the perceived difficulty to drill each angle. The true angle of each hole was measured using a digital goniometer. Results Greater drilling accuracy was achieved at angles closer to 90°. An error of ≤±4° was achieved by 84.5 per cent of participants drilling a 90° angle compared with approximately 20 per cent of participants drilling a 30–45° angle. There was no effect of surgeon experience, task repetition or drill bit size on the mean error for intended versus achieved angle. Increased perception of difficulty was associated with the more acute angles and decreased accuracy, but not experience level. Clinical significance This study shows that surgeon ability to drill accurately (within ±4° error) is limited, particularly at angles ≤60°. In situations where drill angle is critical, use of computer-assisted navigation or custom-made drill guides may be preferable. PMID:27547423

Percussive Force Magnitude in Permafrost

NASA Technical Reports Server (NTRS)

Eustes, A. W., III; Bridgford, E.; Tischler, A.; Wilcox, B. H.

2000-01-01

An in-depth look at percussive drilling shows that the transmission efficiency is very important; however, data for percussive drilling in hard rock or permafrost is rarely available or the existing data are very old. Transmission efficiency can be used as a measurement of the transmission of the energy in the piston to the drill steel or bit and from the bit to the rock. Having a plane and centralized impact of the piston on the drill steel can optimize the transmission efficiency from the piston to the drill steel. A transmission efficiency of near 100% between piston and drill steel is possible. The transmission efficiency between bit and rock is dependent upon the interaction within the entire system. The main factors influencing this transmission efficiency are the contact area between cutting structure and surrounding rock (energy loss due to friction heat), damping characteristics of the surrounding rock (energy dampening), and cuttings transport. Some of these parameters are not controllable. To solve the existing void regarding available drilling data, an experiment for gathering energy data in permafrost for percussive drilling was designed. Fifteen artificial permafrost samples were prepared. The samples differed in the grain size distribution to observe a possible influence of the grain size distribution on the drilling performance. The samples were then manually penetrated (with a sledge-hammer) with two different spikes.

Results from Testing of Two Rotary Percussive Drilling Systems

NASA Technical Reports Server (NTRS)

Kriechbaum, Kristopher; Brown, Kyle; Cady, Ian; von der Heydt, Max; Klein, Kerry; Kulczycki, Eric; Okon, Avi

2010-01-01

The developmental test program for the MSL (Mars Science Laboratory) rotary percussive drill examined the e ect of various drill input parameters on the drill pene- tration rate. Some of the input parameters tested were drill angle with respect to gravity and percussive impact energy. The suite of rocks tested ranged from a high strength basalt to soft Kaolinite clay. We developed a hole start routine to reduce high sideloads from bit walk. The ongoing development test program for the IMSAH (Integrated Mars Sample Acquisition and Handling) rotary percussive corer uses many of the same rocks as the MSL suite. An additional performance parameter is core integrity. The MSL development test drill and the IMSAH test drill use similar hardware to provide rotation and percussion. However, the MSL test drill uses external stabilizers, while the IMSAH test drill does not have external stabilization. In addition the IMSAH drill is a core drill, while the MSL drill uses a solid powdering bit. Results from the testing of these two related drilling systems is examined.

Hydraulic impulse generator and frequency sweep mechanism for borehole applications

DOEpatents

Kolle, Jack J.; Marvin, Mark H.; Theimer, Kenneth J.

2006-11-21

This invention discloses a valve that generates a hydraulic negative pressure pulse and a frequency modulator for the creation of a powerful, broadband swept impulse seismic signal at the drill bit during drilling operations. The signal can be received at monitoring points on the surface or underground locations using geophones. The time required for the seismic signal to travel from the source to the receiver directly and via reflections is used to calculate seismic velocity and other formation properties near the source and between the source and receiver. This information can be used for vertical seismic profiling of formations drilled, to check the location of the bit, or to detect the presence of abnormal pore pressure ahead of the bit. The hydraulic negative pressure pulse can also be used to enhance drilling and production of wells.

Single Piezo-Actuator Rotary-Hammering (SPaRH) Drill

NASA Technical Reports Server (NTRS)

Sherrit, Stewart; Domm, Lukas; Bao, Xiaoqi; Bar-Cohen, Yoseph; Chang, Zensheu; Badescu, Mircea

2012-01-01

The search for present or past life in the Universe is one of the most important objectives of NASA's exploration missions. Drills for subsurface sampling of rocks, ice and permafrost are an essential tool for astrobiology studies on other planets. Increasingly, it is recognized that drilling via a combination of rotation and hammering offers an efficient and effective rapid penetration mechanism. The rotation provides an intrinsic method for removal of cuttings from the borehole while the impact and shear forces aids in the fracturing of the penetrated medium. Conventional drills that use a single actuator are based on a complex mechanism with many parts and their use in future mission involves greater risk of failure and/or may require lubrication that can introduce contamination. In this paper, a compact drill is reported that uses a single piezoelectric actuator to produce hammering and rotation of the bit. A horn with asymmetric grooves was design to impart a longitudinal (hammering) and transverse force (rotation) to a keyed free mass. The drill requires low axial pre-load since the hammering-impacts fracture the rock under the bit kerf and rotate the bit to remove the powdered cuttings while augmenting the rock fracture via shear forces. The vibrations 'fluidize' the powdered cuttings inside the flutes reducing the friction with the auger surface. This action reduces the consumed power and heating of the drilled medium helping to preserve the pristine content of the acquired samples. The drill consists of an actuator that simultaneously impacts and rotates the bit by applying force and torque via a single piezoelectric stack actuator without the need for a gearbox or lever mechanism. This can reduce the development/fabrication cost and complexity. In this paper, the drill mechanism will be described and the test results will be reported and discussed.

Effects of pore pressure and mud filtration on drilling rates in a permeable sandstone

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

Black, A.D.; DiBona, B.; Sandstrom, J.

1983-10-01

During laboratory drilling tests in a permeable sandstone, the effects of pore pressure and mud filtration on penetration rates were measured. Four water-base muds were used to drill four saturated sandstone samples. The drilling tests were conducted at constant borehole pressure with different back pressures maintained on the filtrate flowing from the bottom of the sandstone samples. Bit weight was also varied. Filtration rates were measured while drilling and with the bit off bottom and mud circulating. Penetration rates were found to be related to the difference between the filtration rates measured while drilling and circulating. There was no observedmore » correlation between standard API filtration measurements and penetration rate.« less

Effects of pore pressure and mud filtration on drilling rates in a permeable sandstone

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

Black, A.D.; Dearing, H.L.; DiBona, B.G.

1985-09-01

During laboratory drilling tests in a permeable sandstone, the effects of pore pressure and mud filtration on penetration rates were measured. Four water-based muds were used to drill four saturated sandstone samples. The drilling tests were conducted at constant borehole pressure while different backpressures were maintained on the filtrate flowing from the bottom of the sandstone samples. Bit weight was varied also. Filtration rates were measured while circulating mud during drilling and with the bit off bottom. Penetration rates were found to be related qualitatively to the difference between the filtration rates measured while drilling and circulating. There was nomore » observed correlation between standard API filtration measurements and penetration rate.« less

Percussive Augmenter of Rotary Drills (PARoD)

NASA Technical Reports Server (NTRS)

Badescu, Mircea; Bar-Cohen, Yoseph; Sherrit, Stewart; Bao, Xiaoqi; Chang, Zensheu; Donnelly, Chris; Aldrich, Jack

2012-01-01

Increasingly, NASA exploration mission objectives include sample acquisition tasks for in-situ analysis or for potential sample return to Earth. To address the requirements for samplers that could be operated at the conditions of the various bodies in the solar system, a piezoelectric actuated percussive sampling device was developed that requires low preload (as low as 10N) which is important for operation at low gravity. This device can be made as light as 400g, can be operated using low average power, and can drill rocks as hard as basalt. Significant improvement of the penetration rate was achieved by augmenting the hammering action by rotation and use of a fluted bit to provide effective cuttings removal. Generally, hammering is effective in fracturing drilled media while rotation of fluted bits is effective in cuttings removal. To benefit from these two actions, a novel configuration of a percussive mechanism was developed to produce an augmenter of rotary drills. The device was called Percussive Augmenter of Rotary Drills (PARoD). A breadboard PARoD was developed with a 6.4 mm (0.25 in) diameter bit and was demonstrated to increase the drilling rate of rotation alone by 1.5 to over 10 times. Further, a large PARoD breadboard with 50.8 mm diameter bit was developed and its tests are currently underway. This paper presents the design, analysis and preliminary test results of the percussive augmenter.

Field testing advanced geothermal turbodrill (AGT). Phase 1 final report

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

Maurer, W.C.; Cohen, J.H.

1999-06-01

Maurer Engineering developed special high-temperature geothermal turbodrills for LANL in the 1970s to overcome motor temperature limitations. These turbodrills were used to drill the directional portions of LANL`s Hot Dry Rock Geothermal Wells at Fenton Hill, New Mexico. The Hot Dry Rock concept is to drill parallel inclined wells (35-degree inclination), hydraulically fracture between these wells, and then circulate cold water down one well and through the fractures and produce hot water out of the second well. At the time LANL drilled the Fenton Hill wells, the LANL turbodrill was the only motor in the world that would drill atmore » the high temperatures encountered in these wells. It was difficult to operate the turbodrills continuously at low speed due to the low torque output of the LANL turbodrills. The turbodrills would stall frequently and could only be restarted by lifting the bit off bottom. This allowed the bit to rotate at very high speeds, and as a result, there was excessive wear in the bearings and on the gauge of insert roller bits due to these high rotary speeds. In 1998, Maurer Engineering developed an Advanced Geothermal Turbodrill (AGT) for the National Advanced Drilling and Excavation Technology (NADET) at MIT by adding a planetary speed reducer to the LANL turbodrill to increase its torque and reduce its rotary speed. Drilling tests were conducted with the AGT using 12 1/2-inch insert roller bits in Texas Pink Granite. The drilling tests were very successful, with the AGT drilling 94 ft/hr in Texas Pink Granite compared to 45 ft/hr with the LANL turbodrill and 42 ft/hr with a rotary drill. Field tests are currently being planned in Mexico and in geothermal wells in California to demonstrate the ability of the AGT to increase drilling rates and reduce drilling costs.« less

Tribological tests of wear-resistant coatings used in the production of drill bits of horizontal and inclined drilling

NASA Astrophysics Data System (ADS)

Maslov, A. L.; Markova, I. Yu; Zakharova, E. S.; Polushin, N. I.; Laptev, A. I.

2017-05-01

It is known that modern drilling bit body undergoes significant abrasive wear in the contact area with the solid and the retracted cuttings. For protection of the body rationally use wear-resistant coating, which is welded directly to the body of bit. Before mass use of the developed coverings they need to be investigated by various methods that it was possible to characterize coatings and on the basis of the obtained data to perform optimization of both composition of coatings and technology. Such methods include microstructural studies tribological tests, crack resistance and others. This work is devoted to the tribological tests of imported brand of coatings WokaDur NiA and and domestic brand of coating HR-6750 (both brands manufactured by Ltd “Oerlikon Metco Rus”), used to protect the bit body from abrasive wear.

A Study of Specific Fracture Energy at Percussion Drilling

NASA Astrophysics Data System (ADS)

A, Shadrina; T, Kabanova; V, Krets; L, Saruev

2014-08-01

The paper presents experimental studies of rock failure provided by percussion drilling. Quantification and qualitative analysis were carried out to estimate critical values of rock failure depending on the hammer pre-impact velocity, types of drill bits and cylindrical hammer parameters (weight, length, diameter), and turn angle of a drill bit. Obtained data in this work were compared with obtained results by other researchers. The particle-size distribution in granite-cutting sludge was analyzed in this paper. Statistical approach (Spearmen's rank-order correlation, multiple regression analysis with dummy variables, Kruskal-Wallis nonparametric test) was used to analyze the drilling process. Experimental data will be useful for specialists engaged in simulation and illustration of rock failure.

Wear Detection of Drill Bit by Image-based Technique

NASA Astrophysics Data System (ADS)

Sukeri, Maziyah; Zulhilmi Paiz Ismadi, Mohd; Rahim Othman, Abdul; Kamaruddin, Shahrul

2018-03-01

Image processing for computer vision function plays an essential aspect in the manufacturing industries for the tool condition monitoring. This study proposes a dependable direct measurement method to measure the tool wear using image-based analysis. Segmentation and thresholding technique were used as the means to filter and convert the colour image to binary datasets. Then, the edge detection method was applied to characterize the edge of the drill bit. By using cross-correlation method, the edges of original and worn drill bits were correlated to each other. Cross-correlation graphs were able to detect the difference of the worn edge despite small difference between the graphs. Future development will focus on quantifying the worn profile as well as enhancing the sensitivity of the technique.

30 CFR 57.7004 - Drill mast.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drill mast. 57.7004 Section 57.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in...

30 CFR 56.7004 - Drill mast.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drill mast. 56.7004 Section 56.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in operation unless...

30 CFR 56.7004 - Drill mast.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Drill mast. 56.7004 Section 56.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in operation unless...

30 CFR 57.7004 - Drill mast.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Drill mast. 57.7004 Section 57.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in...

30 CFR 57.7004 - Drill mast.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Drill mast. 57.7004 Section 57.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in...

30 CFR 57.7004 - Drill mast.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Drill mast. 57.7004 Section 57.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in...

30 CFR 56.7004 - Drill mast.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Drill mast. 56.7004 Section 56.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in operation unless...

30 CFR 56.7004 - Drill mast.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Drill mast. 56.7004 Section 56.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in operation unless...

30 CFR 56.7004 - Drill mast.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Drill mast. 56.7004 Section 56.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in operation unless...

30 CFR 57.7004 - Drill mast.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Drill mast. 57.7004 Section 57.7004 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7004 Drill mast. Persons shall not be on a mast while the drill-bit is in...

Utilizing a Pediatric Disaster Coalition Model to Increase Pediatric Critical Care Surge Capacity in New York City.

PubMed

Frogel, Michael; Flamm, Avram; Sagy, Mayer; Uraneck, Katharine; Conway, Edward; Ushay, Michael; Greenwald, Bruce M; Pierre, Louisdon; Shah, Vikas; Gaffoor, Mohamed; Cooper, Arthur; Foltin, George

2017-08-01

A mass casualty event can result in an overwhelming number of critically injured pediatric victims that exceeds the available capacity of pediatric critical care (PCC) units, both locally and regionally. To address these gaps, the New York City (NYC) Pediatric Disaster Coalition (PDC) was established. The PDC includes experts in emergency preparedness, critical care, surgery, and emergency medicine from 18 of 25 major NYC PCC-capable hospitals. A PCC surge committee created recommendations for making additional PCC beds available with an emphasis on space, staff, stuff (equipment), and systems. The PDC assisted 15 hospitals in creating PCC surge plans by utilizing template plans and site visits. These plans created an additional 153 potential PCC surge beds. Seven hospitals tested their plans through drills. The purpose of this article was to demonstrate the need for planning for disasters involving children and to provide a stepwise, replicable model for establishing a PDC, with one of its primary goals focused on facilitating PCC surge planning. The process we describe for developing a PDC can be replicated to communities of any size, setting, or location. We offer our model as an example for other cities. (Disaster Med Public Health Preparedness. 2017;11:473-478).

21 CFR 882.4370 - Pneumatic cranial drill motor.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Pneumatic cranial drill motor. 882.4370 Section... drill motor. (a) Identification. A pneumatic cranial drill motor is a pneumatically operated power source used with removable rotating surgical cutting tools or drill bits on a patient's skull. (b...

21 CFR 882.4370 - Pneumatic cranial drill motor.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Pneumatic cranial drill motor. 882.4370 Section... drill motor. (a) Identification. A pneumatic cranial drill motor is a pneumatically operated power source used with removable rotating surgical cutting tools or drill bits on a patient's skull. (b...

21 CFR 882.4370 - Pneumatic cranial drill motor.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Pneumatic cranial drill motor. 882.4370 Section... drill motor. (a) Identification. A pneumatic cranial drill motor is a pneumatically operated power source used with removable rotating surgical cutting tools or drill bits on a patient's skull. (b...

Structure optimization of a micro drill bit with nonlinear constraints considering the effects of eccentricity, gyroscopic moments, lateral and torsional vibrations

NASA Astrophysics Data System (ADS)

Nguyen, Danh-Tuyen; Hoang, Tien-Dat; Lee, An-Chen

2017-10-01

A micro drill structure was optimized to give minimum lateral displacement at its drill tip, which plays an extremely important role on the quality of drilled holes. A drilling system includes a spindle, chuck and micro drill bit, which are modeled as rotating Timoshenko beam elements considering axial drilling force, torque, gyroscopic moments, eccentricity and bearing reaction force. Based on our previous work, the lateral vibration at the drill tip is evaluated. It is treated as an objective function in the optimization problem. Design variables are diameter and lengths of cylindrical and conical parts of the micro drill, along with nonlinear constraints on its mass and mass center location. Results showed that the lateral vibration was reduced by 15.83 % at a cutting speed of 70000 rpm as compared to that for a commercial UNION drill. Among the design variables, we found that the length of the conical part connecting to the drill shank plays the most important factor on the lateral vibration during cutting process.

Environment-induced quantum coherence spreading of a qubit

NASA Astrophysics Data System (ADS)

Pozzobom, Mauro B.; Maziero, Jonas

2017-02-01

We make a thorough study of the spreading of quantum coherence (QC), as quantified by the l1-norm QC, when a qubit (a two-level quantum system) is subjected to noise quantum channels commonly appearing in quantum information science. We notice that QC is generally not conserved and that even incoherent initial states can lead to transitory system-environment QC. We show that for the amplitude damping channel the evolved total QC can be written as the sum of local and non-local parts, with the last one being equal to entanglement. On the other hand, for the phase damping channel (PDC) entanglement does not account for all non-local QC, with the gap between them depending on time and also on the qubit's initial state. Besides these issues, the possibility and conditions for time invariance of QC are regarded in the case of bit, phase, and bit-phase flip channels. Here we reveal the qualitative dynamical inequivalence between these channels and the PDC and show that the creation of system-environment entanglement does not necessarily imply the destruction of the qubit's QC. We also investigate the resources needed for non-local QC creation, showing that while the PDC requires initial coherence of the qubit, for some other channels non-zero population of the excited state (i.e., energy) is sufficient. Related to that, considering the depolarizing channel we notice the qubit's ability to act as a catalyst for the creation of joint QC and entanglement, without need for nonzero initial QC or excited state population.

Roundness and taper of holes during drilling composites of various thickness by HSS drill bit under dry condition

NASA Astrophysics Data System (ADS)

Sakib, M. S.; Rahman, Motiur; Ferdous, M.; Dhar, N. R.

2017-12-01

Polymer Matrix Composites are extending a wide range of applications in aviation in recent eras because of their better economics, well established processing, high temperature properties, high resistance to corrosion and fatigue. Directional properties of composites are dependent on the fibre orientation. Composites being anisotropic in nature are difficult to drill and machining and tooling of the composites remained a great challenge over time. This paper addresses the issues of various machining problems such as delamination, fibre pull-out, cracks on varying drilling parameters like feed rate and drilling speed. Experimental drilling was carried out on Fibre Reinforced Plastic composites with HSS drill bit. Results reveal that as the number of holes increases the entry and exit diameter and tapper of holes vary and also varying composite thickness results in a difference in hole roundness and tapper. This experiment summarizes that for achieving acceptable tool life and hole quality demands a drill designed with composites.

Foldable Instrumented Bits for Ultrasonic/Sonic Penetrators

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoseph; Badescu, Mircea; Iskenderian, Theodore; Sherrit, Stewart; Bao, Xiaoqi; Linderman, Randel

2010-01-01

Long tool bits are undergoing development that can be stowed compactly until used as rock- or ground-penetrating probes actuated by ultrasonic/sonic mechanisms. These bits are designed to be folded or rolled into compact form for transport to exploration sites, where they are to be connected to their ultrasonic/ sonic actuation mechanisms and unfolded or unrolled to their full lengths for penetrating ground or rock to relatively large depths. These bits can be designed to acquire rock or soil samples and/or to be equipped with sensors for measuring properties of rock or soil in situ. These bits can also be designed to be withdrawn from the ground, restowed, and transported for reuse at different exploration sites. Apparatuses based on the concept of a probe actuated by an ultrasonic/sonic mechanism have been described in numerous prior NASA Tech Briefs articles, the most recent and relevant being "Ultrasonic/ Sonic Impacting Penetrators" (NPO-41666) NASA Tech Briefs, Vol. 32, No. 4 (April 2008), page 58. All of those apparatuses are variations on the basic theme of the earliest ones, denoted ultrasonic/sonic drill corers (USDCs). To recapitulate: An apparatus of this type includes a lightweight, low-power, piezoelectrically driven actuator in which ultrasonic and sonic vibrations are generated and coupled to a tool bit. The combination of ultrasonic and sonic vibrations gives rise to a hammering action (and a resulting chiseling action at the tip of the tool bit) that is more effective for drilling than is the microhammering action of ultrasonic vibrations alone. The hammering and chiseling actions are so effective that the size of the axial force needed to make the tool bit advance into soil, rock, or another material of interest is much smaller than in ordinary twist drilling, ordinary hammering, or ordinary steady pushing. Examples of properties that could be measured by use of an instrumented tool bit include electrical conductivity, permittivity, magnetic field, magnetic permeability, temperature, and any other properties that can be measured by fiber-optic sensors. The problem of instrumenting a probe of this type is simplified, relative to the problem of attaching electrodes in a rotating drill bit, in two ways: (1) Unlike a rotating drill bit, a bit of this type does not have flutes, which would compound the problem of ensuring contact between sensors and the side wall of a hole; and (2) there is no need for slip rings for electrical contact between sensor electronic circuitry and external circuitry because, unlike a rotating drill, a tool bit of this type is not rotated continuously during operation. One design for a tool bit of the present type is a segmented bit with a segmented, hinged support structure (see figure). The bit and its ultrasonic/sonic actuator are supported by a slider/guiding fixture, and its displacement and preload are controlled by a motor. For deployment from the folded configuration, a spring-loaded mechanism rotates the lower segment about the hinges, causing the lower segment to become axially aligned with the upper segment. A latching mechanism then locks the segments of the bit and the corresponding segments of the slider/guiding fixture. Then the entire resulting assembly is maneuvered into position for drilling into the ground. Another design provides for a bit comprising multiple tubular segments with an inner alignment string, similar to a foldable tent pole comprising multiple tubular segments with an inner elastic cable connecting the two ends. At the beginning of deployment, all segments except the first (lowermost) one remain folded, and the ultrasonic/sonic actuator is clamped to the top of the lowermost segment and used to drive this segment into the ground. When the first segment has penetrated to a specified depth, the second segment is connected to the upper end of the first segment to form a longer rigid tubular bit and the actuator is moved to the upper end of the second segnt. The process as described thus far is repeated, adding segments until the desired depth of penetration has been attained. Yet other designs provide for bits in the form of bistable circular- or rectangular- cross-section tubes that can be stowed compactly like rolls of flat tape and become rigidified upon extension to full length, in a manner partly similar to that of a common steel tape measure. Albeit not marketed for use in tool bits, a bistable reeled composite product that transforms itself from a flat coil to a rigid tube of circular cross section when unrolled, is commercially available under the trade name RolaTube(TradeMark) and serves as a model for the further development of tool bits of this subtype.

An interactive drilling simulator for teaching and research

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

Cooper, G.A.; Cooper, A.G.; Bihn, G.

1995-12-31

An interactive program has been constructed that allows a student or engineer to simulate the drilling of an oil well, and to optimize the drilling process by comparing different drilling plans. The program operates in a very user-friendly way, with emphasis on menu and button-driven commands. The simulator may be run either as a training program, with exercises that illustrate various features of the drilling process, as a game, in which a student is set a challenge to drill a well with minimum cost or time under constraints set by an instructor, or as a simulator of a real situationmore » to investigate the merit of different drilling strategies. It has three main parts, a Lithology Editor, a Settings Editor and the simulation program itself. The Lithology Editor allows the student, instructor or engineer to build a real or imaginary sequence of rock layers, each characterized by its mineralogy, drilling and log responses. The Settings Editor allows the definition of all the operational parameters, ranging from the drilling and wear rates of particular bits in specified rocks to the costs of different procedures. The simulator itself contains an algorithm that determines rate of penetration and rate of wear of the bit as drilling continues. It also determines whether the well kicks or fractures, and assigns various other {open_quotes}accident{close_quotes} conditions. During operation, a depth vs. time curve is displayed, together with a {open_quotes}mud log{close_quotes} showing the rock layers penetrated. If desired, the well may be {open_quotes}logged{close_quotes} casings may be set and pore and fracture pressure gradients may be displayed. During drilling, the total time and cost are shown, together with cost per foot in total and for the current bit run.« less

Drilling technique for crystals

NASA Technical Reports Server (NTRS)

Hunter, T.; Miyagawa, I.

1977-01-01

Hole-drilling technique uses special crystal driller in which drill bit rotates at fixed position at speed of 30 rpm while crystal slowly advances toward drill. Technique has been successfully applied to crystal of Rochell salt, Triglycine sulfate, and N-acetyglycine. Technique limits heat buildup and reduces strain on crystal.

Design of a water-powered DTH hammer for deep drilling application

NASA Astrophysics Data System (ADS)

Cho, Min Jae; Kim, Donguk; Oh, Joo Young; Yook, Se-Jin; Kim, Young Won

2017-11-01

A DTH (Down-the-hole) hammer powered by highly pressurized fluid is a drilling tool using the motion of percussion of a drill bit. In retrospect, a DTH by using compressed air as a power source has been widely used in drilling industries such as applications of mining, geothermal etc. On the other hand, another type of a DTH that uses pressurized water, called a water hammer, has recently seen deep drilling applications, while it has been rarely investigated. In this study, we designed a water-powered DTH hammer which mainly consists of several components such as a piston, a poppet valve, a cap and a bit for deep drilling applications. We optimized the components of the hammer on the basis of the results of 1D analysis using commercial software of AMESIM. An experimental study has been also conducted to investigate a performance of the designed water hammer. We measured a pressure distribution inside the hammer system as a function of time, and it thus estimates a frequency of impaction of the bit, which has been also analyzed in frequency domain. In addition, some important parameters have been discussed in conjunction with a limitation of impaction frequency as input pressure. We believe that this study provides design rules of a water-based DTH for deep drilling applications. This work is supported by KITECH of Korean government.

Drilling resistance: A method to investigate bone quality.

PubMed

Lughmani, Waqas A; Farukh, Farukh; Bouazza-Marouf, Kaddour; Ali, Hassan

2017-01-01

Bone drilling is a major part of orthopaedic surgery performed during the internal fixation of fractured bones. At present, information related to drilling force, drilling torque, rate of drill-bit penetration and drill-bit rotational speed is not available to orthopaedic surgeons, clinicians and researchers as bone drilling is performed manually. This study demonstrates that bone drilling force data if recorded in-vivo, during the repair of bone fractures, can provide information about the quality of the bone. To understand the variability and anisotropic behaviour of cortical bone tissue, specimens cut from three anatomic positions of pig and bovine were investigated at the same drilling speed and feed rate. The experimental results showed that the drilling force does not only vary from one animal bone to another, but also vary within the same bone due to its changing microstructure. Drilling force does not give a direct indication of bone quality; therefore it has been correlated with screw pull-out force to provide a realistic estimation of the bone quality. A significantly high value of correlation (r2 = 0.93 for pig bones and r2 = 0.88 for bovine bones) between maximum drilling force and normalised screw pull-out strength was found. The results show that drilling data can be used to indicate bone quality during orthopaedic surgery.

Rotary Percussive Auto-Gopher for Deep Drilling and Sampling

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoseph; Badescu, Mircea; Sherrit, Stewart

2009-01-01

The term "rotary percussive auto-gopher" denotes a proposed addition to a family of apparatuses, based on ultrasonic/ sonic drill corers (USDCs), that have been described in numerous previous NASA Tech Briefs articles. These apparatuses have been designed, variously, for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. In the case of the rotary percussive autogopher, the emphasis would be on developing an apparatus capable of penetrating to, and acquiring samples at, depths that could otherwise be reached only by use of much longer, heavier, conventional drilling-and-sampling apparatuses. To recapitulate from the prior articles about USDCs: A USDC can be characterized as a lightweight, low-power jackhammer in which a piezoelectrically driven actuator generates ultrasonic vibrations and is coupled to a tool bit through a free mass. The bouncing of the free mass between the actuator horn and the drill bit converts the actuator ultrasonic vibrations into sonic hammering of the drill bit. The combination of ultrasonic and sonic vibrations gives rise to a hammering action (and a resulting chiseling action at the tip of the tool bit) that is more effective for drilling than is the microhammering action of ultrasonic vibrations alone. The hammering and chiseling actions are so effective that the size of the axial force needed to make the tool bit advance into soil, rock, or another material of interest is much smaller than in ordinary rotary drilling, ordinary hammering, or ordinary steady pushing. The predecessor of the rotary percussive auto-gopher is an apparatus, now denoted an ultrasonic/sonic gopher and previously denoted an ultrasonic gopher, described in "Ultrasonic/ Sonic Mechanism for Drilling and Coring" (NPO-30291), NASA Tech Briefs Vol. 27, No. 9 (September 2003), page 65. The ultrasonic/sonic gopher is intended for use mainly in acquiring cores. The name of the apparatus reflects the fact that, like a gopher, it periodically stops advancing at the end of the hole to bring excavated material (in this case, a core sample) to the surface, then re-enters the hole to resume the advance of the end of the hole. By use of a cable suspended from a reel on the surface, the gopher is lifted from the hole to remove a core sample, then lowered into the hole to resume the advance and acquire the next core sample.

Mud Gas Logging In A Deep Borehole: IODP Site C0002, Nankai Trough Accretionary Prism

NASA Astrophysics Data System (ADS)

Toczko, S.; Hammerschmidt, S.; Maeda, L.

2014-12-01

Mud logging, a tool in riser drilling, makes use of the essentially "closed-circuit" drilling mud flow between the drilling platform downhole to the bit and then back to the platform for analyses of gas from the formation in the drilling mud, cuttings from downhole, and a range of safety and operational parameters to monitor downhole drilling conditions. Scientific riser drilling, with coincident control over drilling mud, downhole pressure, and returning drilling mud analyses, has now been in use aboard the scientific riser drilling vessel Chikyu since 2009. International Ocean Discovery Program (IODP) Expedition 348, as part of the goal of reaching the plate boundary fault system near ~5000 mbsf, has now extended the deep riser hole (Hole C0002 N & P) to 3058.5 mbsf. The mud gas data discussed here are from two approximately parallel boreholes, one a kick-off from the other; 860-2329 mbsf (Hole C0002N) and 2163-3058 mbsf (Hole C0002P). An approximate overlap of 166 m between the holes allows for some slight depth comparison between the two holes. An additional 55 m overlap at the top of Hole C0002P exists where a 10-5/8-inch hole was cored, and then opened to 12-1/4-inch with logging while drilling (LWD) tools (Fig. 1). There are several fault zones revealed by LWD data, confirmed in one instance by coring. One of the defining formation characteristics of Holes C0002 N/P are the strongly dipping bedding planes, typically exceeding 60º. These fault zones and bedding planes can influence the methane/ethane concentrations found in the returning drilling mud. A focused comparison of free gas in drilling mud between one interval in Hole C0002 P, drilled first with a 10 5/8-inch coring bit and again with an 12 ¼-inch logging while drilling (LWD) bit is shown. Hole C0002N above this was cased all the way from the sea floor to the kick-off section. A fault interval (in pink) was identified from the recovered core section and from LWD resistivity and gamma. The plot of methane and ethane free gas (C1 and C2; ppmv) shows that the yield of free gas (primarily methane) was greater when the LWD bit returned to open the cored hole to a greater diameter. One possible explanation for this is the time delay between coring and LWD operations; approximately 3 days passed between the end of coring and the beginning of LWD (25-28 December 2013).

Boring apparatus capable of boring straight holes

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

Peterson, C.R.

The invention relates to a rock boring assembly for producing a straight hole for use in a drill string above a pilot boring bit of predetermined diameter smaller than the desired final hole size. The boring assembly comprises a small conical boring bit and a larger conical boring, the conical boring bits mounted on lower and upper ends of an enlongated spacer, respectively, and the major effective cutting diameters of each of the conical boring bits being at least 10% greater than the minor effective cutting diameter of the respective bit. The spacer has a cross-section resistant bending and spacesmore » the conical boring bits apart a distance at least 5 times the major cutting diameter of the small conical boring bit, thereby spacing the pivot points provided by the two conical boring bits to limit bodily angular deflection of the assembly and providing a substantial moment arm to resist lateral forces applied to the assembly by the pilot bit and drill string. The spacing between the conical bits is less than about 20 times the major cutting diameter of the lower conical boring bit to enable the spacer to act as a bend-resistant beam to resist angular deflection of the axis of either of the conical boring bits relative to the other when it receives uneven lateral force due to non-uniformity of cutting conditions about the circumference of the bit. Advantageously the boring bits also are self-advancing and feature skewed rollers. 7 claims.« less

Rapid ice drilling with continual air transport of cuttings and cores: General concept

NASA Astrophysics Data System (ADS)

Wang, Rusheng; An, Liu; Cao, Pinlu; Chen, Baoyi; Sysoev, Mikhail; Fan, Dayou; Talalay, Pavel G.

2017-12-01

This article describes the investigation of the feasibility of rapid drilling in ice sheets and glaciers to depths of up to 600 m, with cuttings and cores continually transported by air reverse circulation. The method employs dual wall drill rods. The inner tubes provide a continuous pathway for the chips and cores from the drill bit face to the surface. To modify air reverse circulation drilling technology according to the conditions of a specific glacier, original cutter drill bits and air processing devices (air-cooled aftercoolers, air receivers, coalescing filters, desiccant dryers) should be used. The airflow velocity for conveying a 60-mm diameter and 200-mm long ice core should not be lower than 22.5 m/s, and the minimal airflow rate for continual chip and cores transport is 6.8 m3/min at 2.3-2.6 MPa. Drilling of a 600-m deep hole can be accomplished within 1.5 days in the case of 24 h drilling operations. However, to avoid sticking while drilling through ice, the drilling depth should to be limited to 540 m at a temperature of -20 °C and to 418 m at a temperature of -10 °C.

Method for machining holes in composite materials

NASA Technical Reports Server (NTRS)

Daniels, Julia G. (Inventor); Ledbetter, Frank E., III (Inventor); Clemons, Johnny M. (Inventor); Penn, Benjamin G. (Inventor); White, William T. (Inventor)

1987-01-01

A method for boring well defined holes in a composite material such as graphite/epoxy is discussed. A slurry of silicon carbide powder and water is projected onto a work area of the composite material in which a hole is to be bored with a conventional drill bit. The silicon carbide powder and water slurry allow the drill bit, while experiencing only normal wear, to bore smooth, cylindrical holes in the composite material.

Drilled shaft resistance based on diameter, torque and crowd (drilling resistance vs. Rock strength) phase II : final report.

DOT National Transportation Integrated Search

2016-06-01

The research focused on evaluation of Florida limestones unconfined compressive strength, qu, through : drilling parameters crowd, torque, penetration rate, rotational speed, and bit diameter in both the : laboratory and field for assessin...

Video Clip of a Rover Rock-Drilling Demonstration at JPL

NASA Image and Video Library

2013-02-20

This frame from a video clip shows moments during a demonstration of drilling into a rock at NASA JPL, Pasadena, Calif., with a test double of the Mars rover Curiosity. The drill combines hammering and rotation motions of the bit.

Preparatory Test for First Rock Drilling by Mars Rover Curiosity

NASA Image and Video Library

2013-02-04

The bit in the rotary-percussion drill of NASA Mars rover Curiosity left its mark in a target patch of rock called John Klein during a test on Feb. 2, 2013, in preparation for the first drilling of a rock by the rover.

Lunar deep drill apparatus

NASA Technical Reports Server (NTRS)

Harvey, Jill (Editor)

1989-01-01

A self contained, mobile drilling and coring system was designed to operate on the Lunar surface and be controlled remotely from earth. The system uses SKITTER (Spatial Kinematic Inertial Translatory Tripod Extremity Robot) as its foundation and produces Lunar core samples two meters long and fifty millimeters in diameter. The drill bit used for this is composed of 30 per carat diamonds in a sintered tungsten carbide matrix. To drill up to 50 m depths, the bit assembly will be attached to a drill string made from 2 m rods which will be carried in racks on SKITTER. Rotary power for drilling will be supplied by a Curvo-Synchronous motor. SKITTER is to support this system through a hexagonal shaped structure which will contain the drill motor and the power supply. A micro-coring drill will be used to remove a preliminary sample 5 mm in diameter and 20 mm long from the side of the core. This whole system is to be controlled from earth. This is carried out by a continuously monitoring PLC onboard the drill rig. A touch screen control console allows the operator on earth to monitor the progress of the operation and intervene if necessary.

Method and apparatus for optimizing determination of the originating depth of borehole cuttings

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

Mc Auley, J.A.; Eppler, S.G.

1987-11-24

This patent describes a method for determining the arrival at the surface of an identifiable material from a predetermined drilling depth independent of pump stroke rate and intermittent operations during the utilization of at least a drill bit, a positive displacement mud pump and drilling mud during the drilling of a well. The method comprises the steps of: adding identifiable material to the drilling mud as the drilling mud is being pumped downwardly into the well; initiate count of the pump strokes of the positive displacement mud pump as the previous step occurs; observe arrival of the identifiable material atmore » the surface of the earth as the drilling mud exits from the well; observe the accumulated count of the pump strokes of the positive displacement mud pump which occur between step one and step three; subtract, from the accumulated count of the previous step, the number of pump strokes of the positive displacement mud pump required to pump the identifiable material down to the drill bit to establish a number of lag strokes; and utilize the number obtained in the previous step to identify the arrival of drill cuttings from a predetermined depth.« less

Smaller Footprint Drilling System for Deep and Hard Rock Environments; Feasibility of Ultra-High-Speed Diamond Drilling

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

Arnis Judzis; Homer Robertson; Alan Black

2006-06-22

The two phase program addresses long-term developments in deep well and hard rock drilling. TerraTek believes that significant improvements in drilling deep hard rock will be obtained by applying ultra-high rotational speeds (greater than 10,000 rpm). The work includes a feasibility of concept research effort aimed at development that will ultimately result in the ability to reliably drill ''faster and deeper'' possibly with smaller, more mobile rigs. The principle focus is on demonstration testing of diamond bits rotating at speeds in excess of 10,000 rpm to achieve high rate of penetration (ROP) rock cutting with substantially lower inputs of energymore » and loads. The significance of the ''ultra-high rotary speed drilling system'' is the ability to drill into rock at very low weights on bit and possibly lower energy levels. The drilling and coring industry today does not practice this technology. The highest rotary speed systems in oil field and mining drilling and coring today run less than 10,000 rpm-usually well below 5,000 rpm. This document details the progress at the end of Phase 1 on the program entitled ''Smaller Footprint Drilling System for Deep and Hard Rock Environments: Feasibility of Ultra-High-Speed Diamond Drilling'' for the period starting 1 March 2006 and concluding 30 June 2006. (Note: Results from 1 September 2005 through 28 February 2006 were included in the previous report (see Judzis, Black, and Robertson)). Summarizing the accomplished during Phase 1: {lg_bullet} TerraTek reviewed applicable literature and documentation and convened a project kickoff meeting with Industry Advisors in attendance (see Black and Judzis). {lg_bullet} TerraTek designed and planned Phase I bench scale experiments (See Black and Judzis). Some difficulties continued in obtaining ultra-high speed motors. Improvements were made to the loading mechanism and the rotational speed monitoring instrumentation. New drill bit designs were developed to provided a more consistent product with consistent performance. A test matrix for the final core bit testing program was completed. {lg_bullet} TerraTek concluded Task 3 ''Small-scale cutting performance tests.'' {sm_bullet} Significant testing was performed on nine different rocks. {sm_bullet} Five rocks were used for the final testing. The final tests were based on statistical design of experiments. {sm_bullet} Two full-faced bits, a small diameter and a large diameter, were run in Berea sandstone. {lg_bullet} Analysis of data was completed and indicates that there is decreased specific energy as the rotational speed increases (Task 4). Data analysis from early trials was used to direct the efforts of the final testing for Phase I (Task 5). {lg_bullet} Technology transfer (Task 6) was accomplished with technical presentations to the industry (see Judzis, Boucher, McCammon, and Black).« less

New LWD tools are just in time to probe for baby elephants

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

Ghiselin, D.

Development of sophisticated formation evaluation instrumentation for use while drilling has led to a stratification of while-drilling services. Measurements while drilling (MWD) comprises measurements of mechanical parameters like weight-on-bit, mud pressures, torque, vibration, hole angle and direction. Logging while drilling (LWD) describes resistivity, sonic, and radiation logging which rival wireline measurements in accuracy. A critical feature of LWD is the rate that data can be telemetered to the surface. Early tools could only transmit 3 bits per second one way. In the last decade, the data rate has more than tripled. Despite these improvements, LWD tools have the ability tomore » make many more measurements than can be telemetered in real-time. The paper discusses the development of this technology and its applications.« less

Characterization of rotary-percussion drilling as a seismic-while-drilling source

NASA Astrophysics Data System (ADS)

Xiao, Yingjian; Hurich, Charles; Butt, Stephen D.

2018-04-01

This paper focuses on an evaluation of rotary-percussion drilling (RPD) as a seismic source. Two field experiments were conducted to characterize seismic sources from different rocks with different strengths, i.e. weak shale and hard arkose. Characterization of RPD sources consist of spectral analysis and mean power measurements, along with field measurements of the source radiation patterns. Spectral analysis shows that increase of rock strength increases peak frequency and widens bandwidth, which makes harder rock more viable for seismic-while-drilling purposes. Mean power analysis infers higher magnitude of body waves in RPD than in conventional drillings. Within the horizontal plane, the observed P-wave energy radiation pattern partially confirms the theoretical radiation pattern under a single vertical bit vibration. However a horizontal lobe of energy is observed close to orthogonal to the axial bit vibration. From analysis, this lobe is attributed to lateral bit vibration, which is not documented elsewhere during RPD. Within the horizontal plane, the observed radiation pattern of P-waves is generally consistent with a spherically-symmetric distribution of energy. In addition, polarization analysis is conducted on P-waves recorded at surface geophones for understanding the particle motions. P-wave particle motions are predominantly in the vertical direction showing the interference of the free-surface.

Ultrasonic/Sonic Impacting Penetrators

NASA Technical Reports Server (NTRS)

Bao, Xiaoqi; Bar-Cohen, Yoseph; Chang, Zensheu; Sherrit, Stewart; Stark, Randall A.

2008-01-01

Ultrasonic/sonic impacting penetrators (USIPs) are recent additions to the series of apparatuses based on ultrasonic/sonic drill corers (USDCs). A USIP enables a rod probe to penetrate packed soil or another substance of similar consistency, without need to apply a large axial force that could result in buckling of the probe or in damage to some buried objects. USIPs were conceived for use in probing and analyzing soil to depths of tens of centimeters in the vicinity of buried barrels containing toxic waste, without causing rupture of the barrels. USIPs could also be used for other purposes, including, for example, searching for pipes, barrels, or other hard objects buried in soil; and detecting land mines. USDCs and other apparatuses based on USDCs have been described in numerous previous NASA Tech Briefs articles. The ones reported previously were designed, variously, for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. To recapitulate: A USDC can be characterized as a lightweight, low-power, piezoelectrically driven jackhammer in which ultrasonic and sonic vibrations are generated and coupled to a tool bit. As shown in the figure, a basic USDC includes a piezoelectric stack, a backing and a horn connected to the stack, a free mass (free in the sense that it can slide axially a short distance between the horn and the shoulder of tool bit), and a tool bit, i.e., probe for USIP. The piezoelectric stack is driven at the resonance frequency of the stack/horn/backing assembly to create ultrasonic vibrations that are mechanically amplified by the horn. To prevent fracture during operation, the piezoelectric stack is held in compression by a bolt. The bouncing of the free mass between the horn and the tool bit at sonic frequencies generates hammering actions to the bit that are more effective for drilling than is the microhammering action of ultrasonic vibrations in ordinary ultrasonic drills. The hammering actions are so effective that the axial force needed to make the tool bit advance into the material of interest is much smaller than in ordinary twist drilling, ultrasonic drilling, or ordinary steady pushing.

Continuous chain bit with downhole cycling capability

DOEpatents

Ritter, Don F.; St. Clair, Jack A.; Togami, Henry K.

1983-01-01

A continuous chain bit for hard rock drilling is capable of downhole cycling. A drill head assembly moves axially relative to a support body while the chain on the head assembly is held in position so that the bodily movement of the chain cycles the chain to present new composite links for drilling. A pair of spring fingers on opposite sides of the chain hold the chain against movement. The chain is held in tension by a spring-biased tensioning bar. A head at the working end of the chain supports the working links. The chain is centered by a reversing pawl and piston actuated by the pressure of the drilling mud. Detent pins lock the head assembly with respect to the support body and are also operated by the drilling mud pressure. A restricted nozzle with a divergent outlet sprays drilling mud into the cavity to remove debris. Indication of the centered position of the chain is provided by noting a low pressure reading indicating proper alignment of drilling mud slots on the links with the corresponding feed branches.

Considerations, constraints and strategies for drilling on Mars

NASA Astrophysics Data System (ADS)

Zacny, K.; Cooper, G.

2006-04-01

The effect of the environmental conditions on Mars - low temperature, low pressure, the uncertainty in the nature of the formations to be penetrated and the possibility of encountering ice - imply that a successful drilling system will have to be able to cope with a wide range of conditions. Systems using continuous drill pipe or wireline both offer attractive features and disadvantages, and the preferred choice may depend on the target depth. The drill bit will have to cope with a range of terrain, and we offer some suggestions for making a bit that will be able to drill in both hard and soft formations, and also be able to resist choking if it encounters ice or ice-bound materials. Since it will not be possible to use a liquid to remove the drilled cuttings on Mars, the cuttings removal system will probably use some form of auger, although it may be possible to use continuous or intermittent gas blasts. The sublimation of ice resulting from the heat of drilling in ice-containing formations may help in removing the cuttings, particularly as they are expected to be very fine as a result of the low power available for drilling. Drilling into ice bound soils was also found to be akin to drilling into ice-bound sandstones.

a Self-Excited System for Percussive-Rotary Drilling

NASA Astrophysics Data System (ADS)

Batako, A. D.; Babitsky, V. I.; Halliwell, N. A.

2003-01-01

A dynamic model for a new principle of percussive-rotary drilling is presented. This is a non-linear mechanical system with two degrees of freedom, in which friction-induced vibration is used for excitation of impacts, which influence the parameters of stick-slip motion. The model incorporates the friction force as a function of sliding velocity, which allows for the self-excitation of the coupled vibration of the rotating bit and striker, which tends to a steady state periodic cycle. The dynamic coupling of vibro-impact action with the stick-slip process provides an entirely new adaptive feature in the drilling process. The dynamic behaviour of the system with and without impact is studied numerically. Special attention is given to analysis of the relationship between the sticking and impacting phase of the process in order to achieve an optimal drilling performance. This paper provides an understanding of the mechanics of percussive -rotary drilling and design of new drilling tools with advanced characteristics. Conventional percussive-rotary drilling requires two independent actuators and special control for the synchronization of impact and rotation. In the approach presented, a combined complex interaction of drill bit and striker is synchronized by a single rotating drive.

SMALLER FOOTPRINT DRILLING SYSTEM FOR DEEP AND HARD ROCK ENVIRONMENTS; FEASIBILITY OF ULTRA-HIGH SPEED DIAMOND DRILLING

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

Alan Black; Arnis Judzis

2004-10-01

The two phase program addresses long-term developments in deep well and hard rock drilling. TerraTek believes that significant improvements in drilling deep hard rock will be obtained by applying ultra-high (greater than 10,000 rpm) rotational speeds. The work includes a feasibility of concept research effort aimed at development and test results that will ultimately result in the ability to reliably drill ''faster and deeper'' possibly with rigs having a smaller footprint to be more mobile. The principle focus is on demonstration testing of diamond bits rotating at speeds in excess of 10,000 rpm to achieve high rate of penetration rockmore » cutting with substantially lower inputs of energy and loads. The project draws on TerraTek results submitted to NASA's ''Drilling on Mars'' program. The objective of that program was to demonstrate miniaturization of a robust and mobile drilling system that expends small amounts of energy. TerraTek successfully tested ultrahigh speed ({approx}40,000 rpm) small kerf diamond coring. Adaptation to the oilfield will require innovative bit designs for full hole drilling or continuous coring and the eventual development of downhole ultra-high speed drives. For domestic operations involving hard rock and deep oil and gas plays, improvements in penetration rates is an opportunity to reduce well costs and make viable certain field developments. An estimate of North American hard rock drilling costs is in excess of $1,200 MM. Thus potential savings of $200 MM to $600 MM are possible if drilling rates are doubled [assuming bit life is reasonable]. The net result for operators is improved profit margin as well as an improved position on reserves. The significance of the ''ultra-high rotary speed drilling system'' is the ability to drill into rock at very low weights on bit and possibly lower energy levels. The drilling and coring industry today does not practice this technology. The highest rotary speed systems in oil field and mining drilling and coring today run less than 10,000 rpm--usually well below 5,000 rpm. This document details the progress to date on the program entitled ''SMALLER FOOTPRINT DRILLING SYSTEM FOR DEEP AND HARD ROCK ENVIRONMENTS; FEASIBILITY OF ULTRA-HIGH SPEED DIAMOND DRILLING'' for the period starting June 23, 2003 through September 30, 2004. TerraTek has reviewed applicable literature and documentation and has convened a project kick-off meeting with Industry Advisors in attendance. TerraTek has designed and planned Phase I bench scale experiments. Some difficulties in obtaining ultra-high speed motors for this feasibility work were encountered though they were sourced mid 2004. TerraTek is progressing through Task 3 ''Small-scale cutting performance tests''. Some improvements over early NASA experiments have been identified.« less

SMALLER FOOTPRINT DRILLING SYSTEM FOR DEEP AND HARD ROCK ENVIRONMENTS; FEASIBILITY OF ULTRA-HIGH SPEED DIAMOND DRILLING

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

Alan Black; Arnis Judzis

2004-10-01

The two phase program addresses long-term developments in deep well and hard rock drilling. TerraTek believes that significant improvements in drilling deep hard rock will be obtained by applying ultra-high (greater than 10,000 rpm) rotational speeds. The work includes a feasibility of concept research effort aimed at development and test results that will ultimately result in the ability to reliably drill ''faster and deeper'' possibly with rigs having a smaller footprint to be more mobile. The principle focus is on demonstration testing of diamond bits rotating at speeds in excess of 10,000 rpm to achieve high rate of penetration rockmore » cutting with substantially lower inputs of energy and loads. The project draws on TerraTek results submitted to NASA's ''Drilling on Mars'' program. The objective of that program was to demonstrate miniaturization of a robust and mobile drilling system that expends small amounts of energy. TerraTek successfully tested ultrahigh speed ({approx}40,000 rpm) small kerf diamond coring. Adaptation to the oilfield will require innovative bit designs for full hole drilling or continuous coring and the eventual development of downhole ultra-high speed drives. For domestic operations involving hard rock and deep oil and gas plays, improvements in penetration rates is an opportunity to reduce well costs and make viable certain field developments. An estimate of North American hard rock drilling costs is in excess of $1,200 MM. Thus potential savings of $200 MM to $600 MM are possible if drilling rates are doubled [assuming bit life is reasonable]. The net result for operators is improved profit margin as well as an improved position on reserves. The significance of the ''ultra-high rotary speed drilling system'' is the ability to drill into rock at very low weights on bit and possibly lower energy levels. The drilling and coring industry today does not practice this technology. The highest rotary speed systems in oil field and mining drilling and coring today run less than 10,000 rpm--usually well below 5,000 rpm. This document details the progress to date on the program entitled ''SMALLER FOOTPRINT DRILLING SYSTEM FOR DEEP AND HARD ROCK ENVIRONMENTS; FEASIBILITY OF ULTRA-HIGH SPEED DIAMOND DRILLING'' for the period starting June 23, 2003 through September 30, 2004. (1) TerraTek has reviewed applicable literature and documentation and has convened a project kick-off meeting with Industry Advisors in attendance. (2) TerraTek has designed and planned Phase I bench scale experiments. Some difficulties in obtaining ultra-high speed motors for this feasibility work were encountered though they were sourced mid 2004. (3) TerraTek is progressing through Task 3 ''Small-scale cutting performance tests''. Some improvements over early NASA experiments have been identified.« less

A Novel Well Drill Assisted with High-Frequency Vibration Using the Bending Mode

PubMed Central

Qi, Xinda; Chen, Weishan; Tang, Xintian; Shi, Shengjun

2018-01-01

It is important for companies to increase the efficiency of drilling as well as prolong the lifetime of the drilling tool. Since some previous investigations indicated that a superposition of well drilling with an additional vibration increases the drilling efficiency, this paper introduces a novel well drill which is assisted with additional vibrations by means of piezoelectric sandwich bending vibration transducer. The proposed drill uses bending vibrations in two different directions to from an elliptical trajectory movement, which can help the drill to break the surface of hard material more efficiently and clean away the lithic fragments more easily. The proposed well drill with bending vibration transducer is designed to have a resonance frequency of the first bending vibration mode of about 1779 Hz. The motion equation of the particle on the edge of the drill bit is developed and analyzed. The vibration trajectory of the particle on the edge of the drill bit is calculated by using finite element method. A prototype of the proposed drill using bending vibrations is fabricated and tested to verify the aim of drilling efficiency increase. The feed speed of the vibration assisted drilling is tested to be about 0.296 mm/s when the excitation voltage of the transducer is 300 V, while this speed decreases to about 0.195 mm/s when no vibration is added. This comparison shows that the feed speed of the vibration assisted drilling is about 52% higher than that of the normal drilling, which means the proposed drill has a better efficiency and it is important to consider vibration superimposition in well drilling. In addition, the surface of the drill hole gained by the vibration assisted drilling is smoother than that of the normal drilling, which makes the clearance easier. PMID:29641481

Application of air hammer drilling technology in igneous rocks of Junggar basin

NASA Astrophysics Data System (ADS)

Zhao, Hongshan; Feng, Guangtong; Yu, Haiye

2018-03-01

There were many technical problems such as serious well deviation, low penetration rate and long drilling cycle in igneous rocks because of its hardness, strong abrasive and poor drillability, which severely influenced the exploration and development process of Junggar basin. Through analyzing the difficulties of gas drilling with roller bits in Well HS 2, conducting the mechanics experiments about igneous rock, and deeply describing the rock-breaking mechanism of air hammer drilling and its adaptability in igneous rocks, air hammer drilling can realize deviation control and fast drilling in igneous rocks of piedmont zone and avoid the wear and fatigue fracture of drilling strings due to its characteristics of low WOB, low RPM and high frequency impact. Through firstly used in igneous rocks of Well HS 201, compared with gas drilling with cone bit, the average penetration rate and one-trip footage of air hammer drilling respectively increased by more than 2.45 times and 6.42 times while the well deviation was always controlled less than 2 degrees. Two records for Block HS were set up such as the fastest penetration rate of 14.29m/h in Φ444.5mm well hole and the highest one-trip footage of 470.62m in Φ311.2mm well hole. So air hammer drilling was an effective way to realize optimal and fast drilling in the igneous rock formation of Junggar basin.

Apparatus for downhole drilling communications and method for making and using the same

DOEpatents

Normann, Randy A.; Lockwood, Grant J.; Gonzales, Meliton

1998-01-01

An apparatus for downhole drilling communications is presented. The apparatus includes a spool and end pieces for maintaining the spool at the bottom of a drill string near a drill bit during drilling operations. The apparatus provides a cable for communicating signals between a downhole electronics package and a surface receiver in order to perform measurements while drilling. A method of forming the apparatus is also set forth wherein the apparatus is formed about a central spindle and lathe.

Apparatus for downhole drilling communications and method for making and using the same

DOEpatents

Normann, R.A.; Lockwood, G.J.; Gonzales, M.

1998-03-03

An apparatus for downhole drilling communications is presented. The apparatus includes a spool and end pieces for maintaining the spool at the bottom of a drill string near a drill bit during drilling operations. The apparatus provides a cable for communicating signals between a downhole electronics package and a surface receiver in order to perform measurements while drilling. A method of forming the apparatus is also set forth wherein the apparatus is formed about a central spindle and lathe. 6 figs.

Optimization of process parameters in drilling of fibre hybrid composite using Taguchi and grey relational analysis

NASA Astrophysics Data System (ADS)

Vijaya Ramnath, B.; Sharavanan, S.; Jeykrishnan, J.

2017-03-01

Nowadays quality plays a vital role in all the products. Hence, the development in manufacturing process focuses on the fabrication of composite with high dimensional accuracy and also incurring low manufacturing cost. In this work, an investigation on machining parameters has been performed on jute-flax hybrid composite. Here, the two important responses characteristics like surface roughness and material removal rate are optimized by employing 3 machining input parameters. The input variables considered are drill bit diameter, spindle speed and feed rate. Machining is done on CNC vertical drilling machine at different levels of drilling parameters. Taguchi’s L16 orthogonal array is used for optimizing individual tool parameters. Analysis Of Variance is used to find the significance of individual parameters. The simultaneous optimization of the process parameters is done by grey relational analysis. The results of this investigation shows that, spindle speed and drill bit diameter have most effect on material removal rate and surface roughness followed by feed rate.

Drilling Holes in Graphite/Epoxy Composites

NASA Technical Reports Server (NTRS)

Daniels, J. G.; Ledbetter, Frank E., III; Penn, B. G.; White, W. L.

1986-01-01

Slurry of silicon carbide powder in water fed onto bit while drilling. Slurry contains about 60 percent silicon carbide by weight. Slurry recirculated by low-power pump. With slurry, dull tools cut as fast as, or faster than, sharp ones. Holes drilled rapidly and efficiently regardless of ply orientation; whether unidirectional, quasi-isotropic symmetrical, or cross-ply.

Microhole Test Data

DOE Data Explorer

Su, Jiann

2016-05-23

Drilling results from the microhole project at the Sandia High Operating Temperature test facility. The project is seeking to help reduce the cost of exploration and monitoring of geothermal wells and formations by drilling smaller holes. The tests were part of a control algorithm development to optimize the weight-on-bit (WOB) used during drilling with a percussive hammer.

A cadaveric study of bone tissue temperature during pin site drilling utilizing fluoroptic thermography.

PubMed

Muffly, Matthew; Winegar, Corbett; Miller, Mark Carl; Altman, Gregory

2018-05-03

Using fluoroptic thermography, temperature was measured during pin site drilling of intact cortical human cadaver bone with a combination of one-step drilling, graduated drilling, and one-step drilling with irrigation of 5.0 mm Schanz pins. A 1440 rpm constant force drilling was used to on tibial diaphyses while a sensor probe placed 0.5 mm adjacent to the drill hole measured temperature. Four drilling techniques on each of the tibial segments were performed: 3.5mm drill bit, 5.0mm Schanz pin, 5.0 mm Schanz pin in 3.5 mm pre-drilled entry site, 5.0 mm Schanz pin utilizing irrigation. One-step drilling using a 5.0 mm Schanz pin without irrigation produced a temperature that exceeded the threshold temperature for heat-induced injury in 5 of the 8 trials. With the other three drilling techniques, only one in24 trials produced a temperature that would result in thermal injury. This difference was found to be statistically significant (p = 0.003). The use of irrigation significantly reduced the maximum bone tissue temperature in one-step drilling of a 5.0 mm Schanz pin (p = 0.02). One-step drilling with a 3.5 mm drill bit achieved maximum temperature significantly faster than graduated drilling and drilling with irrigation using a 5.0 mm Schanz pin (p <0.01). One-step drilling with a 5.0 mm Schanz pin into cortical bone can produce temperatures that can lead to heat-induced injury. Irrigation alone can reduce the temperatures sufficiently to avoid damage. Pre-drilling can increase temperatures significantly but the extent of any injury should be small.

Advanced Geothermal Turbodrill

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

W. C. Maurer

2000-05-01

Approximately 50% of the cost of a new geothermal power plant is in the wells that must be drilled. Compared to the majority of oil and gas wells, geothermal wells are more difficult and costly to drill for several reasons. First, most U.S. geothermal resources consist of hot, hard crystalline rock formations which drill much slower than the relatively soft sedimentary formations associated with most oil and gas production. Second, high downhole temperatures can greatly shorten equipment life or preclude the use of some technologies altogether. Third, producing viable levels of electricity from geothermal fields requires the use of largemore » diameter bores and a high degree of fluid communication, both of which increase drilling and completion costs. Optimizing fluid communication often requires creation of a directional well to intersect the best and largest number of fracture capable of producing hot geothermal fluids. Moineau motor stators made with elastomers cannot operate at geothermal temperatures, so they are limited to the upper portion of the hole. To overcome these limitations, Maurer Engineering Inc. (MEI) has developed a turbodrill that does not use elastomers and therefore can operate at geothermal temperatures. This new turbodrill uses a special gear assembly to reduce the output speed, thus allowing a larger range of bit types, especially tri-cone roller bits, which are the bits of choice for drilling hard crystalline formations. The Advanced Geothermal Turbodrill (AGT) represents a significant improvement for drilling geothermal wells and has the potential to significantly reduce drilling costs while increasing production, thereby making geothermal energy less expensive and better able to compete with fossil fuels. The final field test of the AGT will prepare the tool for successful commercialization.« less

Fishing

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

Walker, G.

1984-09-01

Two classifications of fishing jobs are discussed: open hole and cased hole. When there is no casing in the area of the fish, it is called open hole fishing. When the fish is inside the casing, it is called cased hole fishing. The article lists various things that can become a fish-stuck drill pipe, including: broken drill pipe, drill collars, bit, bit cones, hand tools dropped in the well, sanded up or mud stuck tubing, packers become stuck, and much more. It is suggested that on a fishing job, all parties involved should cooperate with each other, and that fishingmore » tool people obtain all the information concerning the well. That way they can select the right tools and methods to clean out the well as quickly as possible.« less

Modeling pellet impact drilling process

NASA Astrophysics Data System (ADS)

Kovalyov, A. V.; Ryabchikov, S. Ya; Isaev, Ye D.; Ulyanova, O. S.

2016-03-01

The paper describes pellet impact drilling which could be used to increase the drilling speed and the rate of penetration when drilling hard rocks. Pellet impact drilling implies rock destruction by metal pellets with high kinetic energy in the immediate vicinity of the earth formation encountered. The pellets are circulated in the bottom hole by a high velocity fluid jet, which is the principle component of the ejector pellet impact drill bit. The experiments conducted has allowed modeling the process of pellet impact drilling, which creates the scientific and methodological basis for engineering design of drilling operations under different geo-technical conditions.

Dog-Bone Horns for Piezoelectric Ultrasonic/Sonic Actuators

NASA Technical Reports Server (NTRS)

Sherrit, Stewart; Bar-Cohen, Yoseph; Chang, Zensheu; Bao, Xiaoqi

2007-01-01

A shape reminiscent of a dog bone has been found to be superior to other shapes for mechanical-amplification horns that are components of piezoelectrically driven actuators used in a series of related devices denoted generally as ultrasonic/sonic drill/corers (USDCs). The first of these devices was reported in Ultrasonic/Sonic Drill/Corers With Integrated Sensors (NPO-20856), NASA Tech Briefs, Vol. 25, No. 1 (January 2001), page 38. The dog-bone shape was conceived especially for use in a more recent device in the series, denoted an ultrasonic/ sonic gopher, that was described in Ultrasonic/Sonic Mechanisms for Drilling and Coring (NPO-30291), NASA Tech Briefs, Vol. 27, No. 9 (September 2003), page 65. The figure shows an example of a dog-bone-shaped horn and other components of an ultrasonic gopher. Prerequisite to a meaningful description of this development is an unavoidably lengthy recapitulation of the principle of operation of a USDC and, more specifically, of the ultrasonic/sonic gopher as described previously in NASA Tech Briefs. The ultrasonic actuator includes a stack of piezoelectric rings, the horn, a metal backing, and a bolt that connects the aforementioned parts and provides compressive pre-strain to the piezoelectric stack to prevent breakage of the rings during extension. The stack of piezoelectric rings is excited at the resonance frequency of the overall ultrasonic actuator. Through mechanical amplification by the horn, the displacement in the ultrasonic vibration reaches tens of microns at the tip of the horn. The horn hammers an object that is denoted the free mass because it is free to move longitudinally over a limited distance between hard stops: The free mass bounces back and forth between the ultrasonic horn and a tool bit (a drill bit or a corer). Because the longitudinal speed of the free mass is smaller than the longitudinal speed of vibration of the tip of the horn, contact between the free mass and the horn tip usually occurs at a phase of the vibration favorable to transfer of momentum from the horn to the free mass. Therefore, the free mass picks up momentum and is accelerated back to the tool bit. Upon impact of the free mass on the tool bit, momentum is transferred to the tool bit. The impacts of the free mass on the tool bit repeat at a sonic frequency that can range from tens of hertz to about 1 kHz. The shock waves caused by the impacts of the free mass propagate to the interface between the tool bit and the medium (typically, rock, ice, or other brittle material) to be drilled or cored. The medium becomes fractured when its ultimate strain is exceeded at the medium/tool-bit interface. This concludes the description of the principle of operation.

Design of a Bottom Impermeable Barrier in Conjunction with A contaminated Site Containment Structure.

DTIC Science & Technology

1994-05-01

utilizes drill bits and tubing to cut through the soil. Unlike the auger method, a slurry mixture is used to keep the drill bit clean and assist in...is applied. In the sleeve pipe method, or also called tube -a-manchette, the sleeve pipe is installed in the grout hole, and sealed in place with a...acts as a one-way valve. allowing grout out of the pipe, but not back into the sleeve. A grouting tube with double packer is used to inject the grout

Acquisition and Retaining Granular Samples via a Rotating Coring Bit

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoseph; Badescu, Mircea; Sherrit, Stewart

2013-01-01

This device takes advantage of the centrifugal forces that are generated when a coring bit is rotated, and a granular sample is entered into the bit while it is spinning, making it adhere to the internal wall of the bit, where it compacts itself into the wall of the bit. The bit can be specially designed to increase the effectiveness of regolith capturing while turning and penetrating the subsurface. The bit teeth can be oriented such that they direct the regolith toward the bit axis during the rotation of the bit. The bit can be designed with an internal flute that directs the regolith upward inside the bit. The use of both the teeth and flute can be implemented in the same bit. The bit can also be designed with an internal spiral into which the various particles wedge. In another implementation, the bit can be designed to collect regolith primarily from a specific depth. For that implementation, the bit can be designed such that when turning one way, the teeth guide the regolith outward of the bit and when turning in the opposite direction, the teeth will guide the regolith inward into the bit internal section. This mechanism can be implemented with or without an internal flute. The device is based on the use of a spinning coring bit (hollow interior) as a means of retaining granular sample, and the acquisition is done by inserting the bit into the subsurface of a regolith, soil, or powder. To demonstrate the concept, a commercial drill and a coring bit were used. The bit was turned and inserted into the soil that was contained in a bucket. While spinning the bit (at speeds of 600 to 700 RPM), the drill was lifted and the soil was retained inside the bit. To prove this point, the drill was turned horizontally, and the acquired soil was still inside the bit. The basic theory behind the process of retaining unconsolidated mass that can be acquired by the centrifugal forces of the bit is determined by noting that in order to stay inside the interior of the bit, the frictional force must be greater than the weight of the sample. The bit can be designed with an internal sleeve to serve as a container for granular samples. This tube-shaped component can be extracted upon completion of the sampling, and the bottom can be capped by placing the bit onto a corklike component. Then, upon removal of the internal tube, the top section can be sealed. The novel features of this device are: center dot A mechanism of acquiring and retaining granular samples using a coring bit without a closed door. center dot An acquisition bit that has internal structure such as a waffle pattern for compartmentalizing or helical internal flute to propel the sample inside the bit and help in acquiring and retaining granular samples. center dot A bit with an internal spiral into which the various particles wedge. center dot A design that provides a method of testing frictional properties of the granular samples and potentially segregating particles based on size and density. A controlled acceleration or deceleration may be used to drop the least-frictional particles or to eventually shear the unconsolidated material near the bit center.

Controllable magneto-rheological fluid-based dampers for drilling

DOEpatents

Raymond, David W [Edgewood, NM; Elsayed, Mostafa Ahmed [Youngsville, LA

2006-05-02

A damping apparatus and method for a drillstring comprising a bit comprising providing to the drillstring a damping mechanism comprising magnetorheological fluid and generating an electromagnetic field affecting the magnetorheological fluid in response to changing ambient conditions encountered by the bit.

Microgravity Drill and Anchor System

NASA Technical Reports Server (NTRS)

Parness, Aaron; Frost, Matthew A.; King, Jonathan P.

2013-01-01

This work is a method to drill into a rock surface regardless of the gravitational field or orientation. The required weight-on-bit (WOB) is supplied by a self-contained anchoring mechanism. The system includes a rotary percussive coring drill, forming a complete sampling instrument usable by robot or human. This method of in situ sample acquisition using micro - spine anchoring technology enables several NASA mission concepts not currently possible with existing technology, including sampling from consolidated rock on asteroids, providing a bolt network for astronauts visiting a near-Earth asteroid, and sampling from the ceilings or vertical walls of lava tubes and cliff faces on Mars. One of the most fundamental parameters of drilling is the WOB; essentially, the load applied to the bit that allows it to cut, creating a reaction force normal to the surface. In every drilling application, there is a minimum WOB that must be maintained for the system to function properly. In microgravity (asteroids and comets), even a small WOB could not be supported conventionally by the weight of the robot or astronaut. An anchoring mechanism would be needed to resist the reactions, or the robot or astronaut would push themselves off the surface and into space. The ability of the system to anchor itself to a surface creates potential applications that reach beyond use in low gravity. The use of these anchoring mechanisms as end effectors on climbing robots has the potential of vastly expanding the scope of what is considered accessible terrain. Further, because the drill is supported by its own anchor rather than by a robotic arm, the workspace is not constrained by the reach of such an arm. Yet, if the drill is on a robotic arm, it has the benefit of not reflecting the forces of drilling back to the arm s joints. Combining the drill with the anchoring feet will create a highly mobile, highly stable, and highly reliable system. The drilling system s anchor uses hundreds of microspine toes that independently find holes and ledges on a rock to create an anchor. Once the system is anchored, a linear translation mechanism moves the drill axially into the surface while maintaining the proper WOB. The linear translation mechanism is composed of a ball screw and stepper motor that can translate a carriage with high precision and applied load. The carriage slides along rails using self-aligning linear bearings that correct any axial misalignment caused by bending and torsion. The carriage then compresses a series of springs that simultaneously transmit the load to the drill along the bit axis and act as a suspension that compensates for the vibration caused by percussive drilling. The drill is a compacted, modified version of an off-the-shelf rotary percussive drill, which uses a custom carbide-tipped coring bit. By using rotary percussive drilling, the drill time is greatly reduced. The percussive action fractures the rock debris, which is removed during rotation. The final result is a 0.75-in. (.1.9- cm) diameter hole and a preserved 0.5- in. (.1.3-cm) diameter rock core. This work extends microspine technology, making it applicable to astronaut missions to asteroids and a host of robotic sampling concepts. At the time of this reporting, it is the first instrument to be demonstrated using microspine anchors, and is the first self-contained drill/anchor system to be demonstrated that is capable of drilling in inverted configurations and would be capable of drilling in microgravity.

Preparation on Earth for Drilling on Mars

NASA Image and Video Library

2013-02-20

The development of the Mars rover Curiosity capabilities for drilling into a rock on Mars required years of development work. Seen here are some of the rocks used in bit development testing and lifespan testing at JPL in 2007.

Lunar drill and test apparatus

NASA Technical Reports Server (NTRS)

Norrington, David W.; Ardoin, Didier C.; Alexander, Stephen G.; Rowland, Philip N.; Vastakis, Frank N.; Linsey, Steven L.

1988-01-01

The design of an experimental lunar drill and a facility to test the drill under simulated lunar conditions is described. The drill utilizes a polycrystalline diamond compact drag bit and an auger to mechanically remove cuttings from the hole. The drill will be tested in a vacuum chamber and powered through a vacuum seal by a drive mechanism located above the chamber. A general description of the design is provided followed by a detailed description and analysis of each component. Recommendations for the further development of the design are included.

Kick Detection at the Bit: Early Detection via Low Cost Monitoring

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

Tost, Brian; Rose, Kelly; Aminzadeh, Fred

2016-06-07

Formation fluid influxes (i.e. kicks) pose persistent challenges and operational costs during drilling operations. Implications of kicks range in scale but cumulatively result in substantial costs that affect drilling safety, environment, schedule, and infrastructure. Early kick detection presents a low-cost, easily adopted solution for avoiding well control challenges associated with kicks near the bit. Borehole geophysical tools used during the drilling process as part of the logging-while-drilling (LWD) and measurement-while-drilling (MWD) provide the advantage of offering real-time downhole data. LWD/MWD collect data on both the annulus and borehole wall. The annular data are normally treated as background, and are filteredmore » out to isolate the formation measurements. Because kicks will change the local physical properties of annular fluids, bottom-hole measurements are among the first indicators that a formation fluid has invaded the wellbore. This report describes and validates a technique for using the annular portion of LWD/MWD data to facilitate early kick detection using first order principles. The detection technique leverages data from standard and cost-effective technologies that are typically implemented during well drilling, such as MWD/LWD data in combination with mud-pulse telemetry for data transmission.« less

IceBreaker: Mars Drill and Sample Delivery System

NASA Astrophysics Data System (ADS)

Mellerowicz, B. L.; Paulsen, G. L.; Zacny, K.; McKay, C.; Glass, B. J.; Dave, A.; Davila, A. F.; Marinova, M.

2012-12-01

We report on the development and testing of a one meter class prototype Mars drill and cuttings sample delivery system. The IceBreaker drill consists of a rotary-percussive drill head, a sampling auger with a bit at the end having an integrated temperature sensor, a Z-stage for advancing the auger into the ground, and a sam-pling station for moving the augered ice shavings or soil cuttings into a sample cup. The drill is deployed from a 3 Degree of Freedom (DOF) robotic arm. The drill demonstrated drilling in ice-cemented ground, ice, and rocks at the 1-1-100-100 level; that is the drill reached 1 meter in 1 hour with 100 Watts of power and 100 Newton Weight on Bit. This cor-responds to an average energy of 100 Whr. The drill has been extensively tested in the Mars chamber to a depth of 1 meter, as well as in the Antarctic and the Arctic Mars analog sites. We also tested three sample delivery systems: 1) 4 DOF arm with a custom soil scoop at the end; 2) Pneumatic based, and 3) Drill based enabled by the 3 (DOF) drill deployment boom. In all approaches there is an air-gap between the sterilized drill (which penetrates subsurface) and the sample transfer hardware (which is not going to be sterilized). The air gap satisfies the planetary protection requirements. The scoop acquires cuttings sample once they are augered to the surface, and drops them into an in-strument inlet port. The system has been tested in the Mars chamber and in the Arctic. The pneumatic sample delivery system uses compressed gas to move the sample captured inside a small chamber inte-grated with the auger, directly into the instrument. The system was tested in the Mars chamber. In the third approach the drill auger captures the sample on its flutes, the 3 DOF boom positions the tip of the auger above the instrument, and then the auger discharges the sample into an instrument. This approach was tested in the labolatory (at STP). The above drilling and sample delivery tests have shown that drilling and sample transfer on Mars, in ice cemented ground with limited power, energy and Weight on Bit, and collecting samples in dis-crete depth intervals is possible within the given mass, power, and energy levels of a Phoenix-size lander and within the duration of a Phoenix-like mission.

Real-time positioning technology in horizontal directional drilling based on magnetic gradient tensor measurement

NASA Astrophysics Data System (ADS)

Deng, Guoqing; Yao, Aiguo

2017-04-01

Horizontal directional drilling (HDD) technology has been widely used in Civil Engineering. The dynamic position of the drill bit during construction is one of significant facts determining the accuracy of the trajectory of HDD. A new method now has been proposed to detecting the position of drill bit by measuring the magnetic gradient tensor of the ground solenoid magnetic beacon. Compared with traditional HDD positioning technologies, this new model is much easier to apply with lower request for construction sites and higher positioning efficiency. A direct current (DC) solenoid as a magnetic dipole is placed on ground near the drill bit, and related sensors array which contains four Micro-electromechanical Systems (MEMS ) tri-axial magnetometers, one MEMS tri-axial accelerometer and one MEMS tri-axial gyroscope is set up for measuring the magnetic gradient tensor of the magnetic dipole. The related HDD positioning model has been established and simulation experiments have been carried out to verify the feasibility and reliability of the proposed method. The experiments show that this method has good positioning accuracy in horizontal and vertical direction, and totally avoid the impact of the environmental magnetic field. It can be found that the posture of the magnetic beacon will impact the remote positioning precision within valid positioning range, and the positioning accuracy is higher with longer baseline for limited space in drilling tools. The results prove that the relative error can be limited in 2% by adjusting position of the magnetic beacon, the layers of the enameled coil, the sensitive of magnetometers and the baseline distance. Conclusion can be made that this new method can be applied in HDD positioning with better effect and wider application range than traditional method.

Auto-Gopher: A Wire-Line Rotary-Hammer Ultrasonic Drill

NASA Technical Reports Server (NTRS)

Badescu, Mircea; Sherrit, Stewart; Bao, Xiaogi; Bar-Cohen, Yoseph; Chen, Beck

2011-01-01

Developing technologies that would enable NASA to sample rock, soil, and ice by coring, drilling or abrading at a significant depth is of great importance for a large number of in-situ exploration missions as well as for earth applications. Proven techniques to sample Mars subsurface will be critical for future NASA astrobiology missions that will search for records of past and present life on the planet, as well as, the search for water and other resources. A deep corer, called Auto-Gopher, is currently being developed as a joint effort of the JPL's NDEAA laboratory and Honeybee Robotics Corp. The Auto-Gopher is a wire-line rotary-hammer drill that combines rock breaking by hammering using an ultrasonic actuator and cuttings removal by rotating a fluted bit. The hammering mechanism is based on the Ultrasonic/Sonic Drill/Corer (USDC) that has been developed as an adaptable tool for many of drilling and coring applications. The USDC uses an intermediate free-flying mass to transform the high frequency vibrations of the horn tip into a sonic hammering of a drill bit. The USDC concept was used in a previous task to develop an Ultrasonic/Sonic Ice Gopher. The lessons learned from testing the ice gopher were implemented into the design of the Auto-Gopher by inducing a rotary motion onto the fluted coring bit. A wire-line version of such a system would allow penetration of significant depth without a large increase in mass. A laboratory version of the corer was developed in the NDEAA lab to determine the design and drive parameters of the integrated system. The design configuration lab version of the design and fabrication and preliminary testing results are presented in this paper

Experimental and analytical investigation of the thermal necrosis in high-speed drilling of bone.

PubMed

Shakouri, Ehsan; Sadeghi, Mohammad H; Maerefat, Mehdi; Shajari, Shaghayegh

2014-04-01

Bone loss due to thermo necrosis may weaken the purchase of surgically placed screws and pins, causing them to loosen postoperatively. The heat generated during the bone drilling is proportional to cutting speed and force and may be partially dissipated by the blood and tissue fluids, and somehow carried away by the chips formed. Increasing cutting speed will reduce cutting force and machining time. Therefore, it is of interest to study the effects of the increasing cutting speed on bone drilling characteristics. In this article, the effects of the increasing cutting speed ranging from 500 up to 18,000 r/min on the thrust force and the temperature rise are studied for bovine femur bone. The results of this study reveal that the high-speed drilling of 6000-7000 r/min may effectively reduce the two parameters of maximum cortical temperature and duration of exposure at temperatures above the allowable levels, which in turn reduce the probability of thermal necrosis in the drill site. This is due to the reduction of the cutting force and the increase in the chip disposal speed. However, more increases in the drill bit rotational speed result in an increase in the amount of temperature elevation, not because of sensible change in drilling force but a considerable increase in friction among the chips, drill bit and the hole walls.

Drill System Development for the Lunar Subsurface Exploration

NASA Astrophysics Data System (ADS)

Zacny, Kris; Davis, Kiel; Paulsen, Gale; Roberts, Dustyn; Wilson, Jack; Hernandez, Wilson

Reaching the cold traps at the lunar poles and directly sensing the subsurface regolith is a primary goal of lunar exploration, especially as a means of prospecting for future In Situ Resource Utilization efforts. As part of the development of a lunar drill capable of reaching a depth of two meters or more, Honeybee Robotics has built a laboratory drill system with a total linear stroke of 1 meter, capability to produce as much as 45 N-m of torque at a rotational speed of 200 rpm, and a capability of delivering maximum downforce of 1000 N. Since this is a test-bed, the motors were purposely chosen to be relative large to provide ample power to the drill system (the Apollo drill was a 500 Watt drill, i.e. not small in current standards). In addition, the drill is capable of using three different drilling modes: rotary, rotary percussive and percussive. The frequency of percussive impact can be varied if needed while rotational speed can be held constant. An integral part of this test bed is a vacuum chamber that is currently being constructed. The drill test-bed is used for analyzing various drilling modes and testing different drill bit and auger systems under low pressure conditions and in lunar regolith simulant. The results of the tests are used to develop final lunar drill design as well as efficient drilling protocols. The drill was also designed to accommodate a downhole neutron spectrometer for measuring the amount of hydrated material in the area surrounding the borehole, as well as downhole temperature sensors, accelerometers, and electrical properties tester. The presentation will include history of lunar drilling, challenges of drilling on the Moon, a description of the drill and chamber as well as preliminary drilling test results conducted in the ice-bound lunar regolith simulant with a variety of drill bits and augers systems.

Drill pipe threaded nipple connection design development

NASA Astrophysics Data System (ADS)

Saruev, A. L.; Saruev, L. A.; Vasenin, S. S.

2015-11-01

The paper presents the analysis of the behavior of the drill pipe nipple connection under the additional load generated by power pulses. The strain wave propagation through the nipple thread connection of drill pipes to the bottomhole is studied in this paper. The improved design of the nipple thread connection is suggested using the obtained experimental and theoretical data. The suggested connection design allows not only the efficient transmission of strain wave energy to a drill bit but also the automation of making-up and breaking-out drill pipes.

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

Bourdon, J.C.; Peltier, B.; Cooper, G.A.

In this paper, field drill-off test results are compared with data from laboratory simulations. A simple theory for analyzing drill-off tests is developed. The weight-on bit (WOB) decay with time is close to exponential, but large threshold WOB's, resulting from poor weight transmission downhole, are sometimes observed in field tests.

Microfluidic devices connected to fused-silica capillaries with minimal dead volume.

PubMed

Bings, N H; Wang, C; Skinner, C D; Colyer, C L; Thibault, P; Harrison, D J

1999-08-01

Fused-silica capillaries have been connected to microfluidic devices for capillary electrophoresis by drilling into the edge of the device using 200-μm tungsten carbide drills. The standard pointed drill bits create a hole with a conical-shaped bottom that leads to a geometric dead volume of 0.7 nL at the junction, and significant band broadening when used with 0.2-nL sample plugs. The plate numbers obtained on the fused-silica capillary connected to the chip were about 16-25% of the predicted numbers. The conical area was removed with a flat-tipped drill bit and the band broadening was substantially eliminated (on average 98% of the predicted plate numbers were observed). All measurements were made while the device was operating with an electrospray from the end of the capillary. The effective dead volume of the flat-bottom connection is minimal and allows microfluidic devices to be connected to a wide variety of external detectors.

Study on the influence of parameters of medical drill on bone drilling temperature

NASA Astrophysics Data System (ADS)

XU, Xianchun; Hu, Yahui; Han, Jingwang; Yue, Lin; Jiang, Wangbiao

2018-03-01

During surgical interventions, the temperature generated during cortical bone drilling can affect the activity of bone material, which may lead to necrosis. In this paper, with the purpose of reducing the temperature during cortical bone drilling, the influence of the parameters of medical drill were analyzed. The finite element model of the drilling process was established based on the parametric design of the dril. The relationship between the drill bit diameter, the point angle, and the helix angle to the drilling temperature was studied by the center composite experiment. The results showed that the drilling temperature is increased with the increase of drill diameter, vertex angle and helix angle in the range of certain research.

Seismic While Drilling Case Study in Shengli Oilfield, Eastern China

NASA Astrophysics Data System (ADS)

Wang, L.; Liu, H.; Tong, S.; Zou, Z.

2015-12-01

Seismic while drilling (SWD) is a promising borehole seismic technique with reduction of drilling risk, cost savings and increased efficiency. To evaluate the technical and economic benefits of this new technique, we carried out SWD survey at well G130 in Shengli Oilfield of Eastern China. Well G130 is an evaluation well, located in Dongying depression at depth more than 3500m. We used an array of portable seismometers to record the surface SWD-data, during the whole drilling progress. The pilot signal was being recorded continuously, by an accelerometer mounted on the top of the drill string. There were also two seismometers buried in the drill yard, one near diesel engine and another near derrick. All the data was being recorded continuously. According to mud logging data, we have processed and analyzed all the data. It demonstrates the drill yard noise is the primary noise among the whole surface wavefield and its dominant frequency is about 20Hz. Crosscorrelation of surface signal with the pilot signal shows its SNR is severely low and there is no any obvious event of drill-bit signals. Fortunately, the autocorrelation of the pilot signal shows clear BHA multiple and drill string multiple. The period of drill string multiple can be used for establishing the reference time (so-called zero time). We identified and removed different noises from the surface SWD-data, taking advantages of wavefield analysis. The drill-bit signal was retrieved from surface SWD-data, using seismic interferometry. And a reverse vertical seismic profile (RVSP) data set for the continuous drilling depth was established. The subsurface images derived from these data compare well with the corresponding images of 3D surface seismic survey cross the well.

Geothermal well drilling manual at Cerro Prieto

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

Fernandez P., A.; Flores S., M.

The objective of the drilling manual is to solve all problems directly related to drilling during the construction of a well. In this case, the topics dealt which are drilling fluids and hydraulics to be applied in the field to improve drilling progress, eliminate risks and achieve good well-completion. There are other topics that are applicable such as drill bits and the drilling string, which are closely linked to drilling progress. On this occasion drilling fluid and hydraulics programs are presented, in addition to a computing program for a Casio FX-502P calculator to be applied in the field to optimizemore » hydraulics and in the analysis of hydraulics for development and exploration wells at their different intervals.« less

Real-Time Prediction of Temperature Elevation During Robotic Bone Drilling Using the Torque Signal.

PubMed

Feldmann, Arne; Gavaghan, Kate; Stebinger, Manuel; Williamson, Tom; Weber, Stefan; Zysset, Philippe

2017-09-01

Bone drilling is a surgical procedure commonly required in many surgical fields, particularly orthopedics, dentistry and head and neck surgeries. While the long-term effects of thermal bone necrosis are unknown, the thermal damage to nerves in spinal or otolaryngological surgeries might lead to partial paralysis. Previous models to predict the temperature elevation have been suggested, but were not validated or have the disadvantages of computation time and complexity which does not allow real time predictions. Within this study, an analytical temperature prediction model is proposed which uses the torque signal of the drilling process to model the heat production of the drill bit. A simple Green's disk source function is used to solve the three dimensional heat equation along the drilling axis. Additionally, an extensive experimental study was carried out to validate the model. A custom CNC-setup with a load cell and a thermal camera was used to measure the axial drilling torque and force as well as temperature elevations. Bones with different sets of bone volume fraction were drilled with two drill bits ([Formula: see text]1.8 mm and [Formula: see text]2.5 mm) and repeated eight times. The model was calibrated with 5 of 40 measurements and successfully validated with the rest of the data ([Formula: see text]C). It was also found that the temperature elevation can be predicted using only the torque signal of the drilling process. In the future, the model could be used to monitor and control the drilling process of surgeries close to vulnerable structures.

Experimental and numerical study of drill bit drop tests on Kuru granite

NASA Astrophysics Data System (ADS)

Fourmeau, Marion; Kane, Alexandre; Hokka, Mikko

2017-01-01

This paper presents an experimental and numerical study of Kuru grey granite impacted with a seven-buttons drill bit mounted on an instrumented drop test machine. The force versus displacement curves during the impact, so-called bit-rock interaction (BRI) curves, were obtained using strain gauge measurements for two levels of impact energy. Moreover, the volume of removed rock after each drop test was evaluated by stereo-lithography (three-dimensional surface reconstruction). A modified version of the Holmquist-Johnson-Cook (MHJC) material model was calibrated using Kuru granite test results available from the literature. Numerical simulations of the single drop tests were carried out using the MHJC model available in the LS-DYNA explicit finite-element solver. The influence of the impact energy and additional confining pressure on the BRI curves and the volume of the removed rock is discussed. In addition, the influence of the rock surface shape before impact was evaluated using two different mesh geometries: a flat surface and a hyperbolic surface. The experimental and numerical results are compared and discussed in terms of drilling efficiency through the mechanical specific energy. This article is part of the themed issue 'Experimental testing and modelling of brittle materials at high strain rates'.

Rigid and Flexible Pavement Aircraft Tie-Downs

DTIC Science & Technology

2010-05-01

Concrete Pier, Prior to PCC Placement Neenah anchors are equipped with two ½-in-diameter cored holes to allow insertion of a section of rebar through...facilitate this process, a Hilti drill was utilized to perform the concrete drilling process. The drill bit diameter exceeded the rebar diameter by...aggregate particles not become lodged against the rebar sections inside the dowel sleeves, impeding the flow of concrete and possibly creating air voids

Environmental Measurement-While-Drilling system for real-time field screening of contaminants

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

Lockwood, G.J.; Normann, R.A.; Bishop, L.B.

Sampling during environmental drilling is essential to fully characterize the spatial distribution and migration of near surface contaminants. However, the analysis of these samples is not only expensive, but can take weeks or months when sent to an off-site laboratory. In contrast, measurement-while-drilling (MWD) screening capability could save money and valuable time by quickly distinguishing between contaminated and uncontaminated areas. Real-time measurements provided by a MVM system would enable on-the-spot decisions to be made regarding sampling strategies, enhance worker safety, and provide the added flexibility of being able to ``steer`` the drill bit in or out hazardous zones. During measurement-while-drilling,more » down-hole sensors are located behind the drill bit and linked by a rapid data transmission system to a computer at the surface. As drilling proceeds, data are collected on the nature and extent of the subsurface contamination in real-time. The down-hole sensor is a Geiger-Mueller tube (GMT) gamma radiation detector. In addition to the GMT signal, the MWD system monitors these required down-hole voltages and two temperatures associated with the detector assembly. The Gamma Ray Detection System (GRDS) and electronics package are discussed in as well as the results of the field test. Finally, our conclusions and discussion of future work are presented.« less

Seismic while drilling: Operational experiences in Viet Nam

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

Jackson, M.; Einchcomb, C.

1997-03-01

The BP/Statoil alliance in Viet Nam has used seismic while drilling on four wells during the last two years. Three wells employed the Western Atlas Tomex system, and the last well, Schlumberger`s SWD system. Perceived value of seismic while drilling (SWD) lies in being able to supply real-time data linking drill bit position to a seismic picture of the well. However, once confidence in equipment and methodology is attained, SWD can influence well design and planning associated with drilling wells. More important, SWD can remove uncertainty when actually drilling wells, allowing risk assessment to be carried out more accurately andmore » confidently.« less

Summary: High Temperature Downhole Motor

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

Raymond, David W.

2017-10-01

Directional drilling can be used to enable multi-lateral completions from a single well pad to improve well productivity and decrease environmental impact. Downhole rotation is typically developed with a motor in the Bottom Hole Assembly (BHA) that develops drilling power (speed and torque) necessary to drive rock reduction mechanisms (i.e., the bit) apart from the rotation developed by the surface rig. Historically, wellbore deviation has been introduced by a “bent-sub,” located in the BHA, that introduces a small angular deviation, typically less than 3 degrees, to allow the bit to drill off-axis with orientation of the BHA controlled at themore » surface. The development of a high temperature downhole motor would allow reliable use of bent subs for geothermal directional drilling. Sandia National Laboratories is pursuing the development of a high temperature motor that will operate on either drilling fluid (water-based mud) or compressed air to enable drilling high temperature, high strength, fractured rock. The project consists of designing a power section based upon geothermal drilling requirements; modeling and analysis of potential solutions; and design, development and testing of prototype hardware to validate the concept. Drilling costs contribute substantially to geothermal electricity production costs. The present development will result in more reliable access to deep, hot geothermal resources and allow preferential wellbore trajectories to be achieved. This will enable development of geothermal wells with multi-lateral completions resulting in improved geothermal resource recovery, decreased environmental impact and enhanced well construction economics.« less

Auto-Gopher-II: an autonomous wireline rotary-hammer ultrasonic drill

NASA Astrophysics Data System (ADS)

Badescu, Mircea; Lee, Hyeong Jae; Sherrit, Stewart; Bao, Xiaoqi; Bar-Cohen, Yoseph; Jackson, Shannon; Chesin, Jacob; Zacny, Kris; Paulsen, Gale L.; Mellerowicz, Bolek; Kim, Daniel

2017-04-01

Developing technologies that would enable future NASA exploration missions to penetrate deeper into the subsurface of planetary bodies for sample collection is of great importance. Performing these tasks while using minimal mass/volume systems and with low energy consumption is another set of requirements imposed on such technologies. A deep drill, called Auto-Gopher II, is currently being developed as a joint effort between JPL's NDEAA laboratory and Honeybee Robotics Corp. The Auto-Gopher II is a wireline rotary-hammer drill that combines formation breaking by hammering using an ultrasonic actuator and cuttings removal by rotating a fluted auger bit. The hammering mechanism is based on the Ultrasonic/Sonic Drill/Corer (USDC) mechanism that has been developed as an adaptable tool for many drilling and coring applications. The USDC uses an intermediate free-flying mass to transform high frequency vibrations of a piezoelectric transducer horn tip into sonic hammering of the drill bit. The USDC concept was used in a previous task to develop an Ultrasonic/Sonic Ice Gopher and then integrated into a rotary hammer device to develop the Auto-Gopher-I. The lessons learned from these developments are being integrated into the development of the Auto- Gopher-II, an autonomous deep wireline drill with integrated cuttings and sample management and drive electronics. Subsystems of the wireline drill are being developed in parallel at JPL and Honeybee Robotics Ltd. This paper presents the development efforts of the piezoelectric actuator, cuttings removal and retention flutes and drive electronics.

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

Robert Radtke

The manufacture of thermally stable diamond (TSP) cutters for drill bits used in petroleum drilling requires the brazing of two dissimilar materials--TSP diamond and tungsten carbide. The ENDURUS{trademark} thermally stable diamond cutter developed by Technology International, Inc. exhibits (1) high attachment (shear) strength, exceeding 345 MPa (50,000 psi), (2) TSP diamond impact strength increased by 36%, (3) prevents TSP fracture when drilling hard rock, and (4) maintains a sharp edge when drilling hard and abrasive rock. A novel microwave brazing (MWB) method for joining dissimilar materials has been developed. A conventional braze filler metal is combined with microwave heating whichmore » minimizes thermal residual stress between materials with dissimilar coefficients of thermal expansion. The process results in preferential heating of the lower thermal expansion diamond material, thus providing the ability to match the thermal expansion of the dissimilar material pair. Methods for brazing with both conventional and exothermic braze filler metals have been developed. Finite element modeling (FEM) assisted in the fabrication of TSP cutters controllable thermal residual stress and high shear attachment strength. Further, a unique cutter design for absorbing shock, the densification of otherwise porous TSP diamond for increased mechanical strength, and diamond ion implantation for increased diamond fracture resistance resulted in successful drill bit tests.« less

Proof of principal for staircase auger chip removal theory

NASA Technical Reports Server (NTRS)

Barron, Jeffrey B.; Brewer, Steve; Kerns, Kenneth; Moody, Kyle; Rossi, Richard A.

1987-01-01

A proof of principal design of the staircase auger theory is provided for lunar drilling. The drill is designed to drill holes 30 meters deep and 0.1 meters in diameter. The action of the auger is 0.01 meter strokes at a varying number of strokes per second. A detailed analysis of the interaction of the auger and particle was done to optimize the parameters of the auger. This optimum design will allow for proper heat removal and reasonable drilling time. The drill bit is designed to scoop the particles into the auger while efficiently cutting through the moon's surface.

Advantages and limitations of remotely operated sea floor drill rigs

NASA Astrophysics Data System (ADS)

Freudenthal, T.; Smith, D. J.; Wefer, G.

2009-04-01

A variety of research targets in marine sciences including the investigation of gas hydrates, slope stability, alteration of oceanic crust, ore formation and palaeoclimate can be addressed by shallow drilling. However, drill ships are mostly used for deep drillings, both because the effort of building up a drill string from a drill ship to the deep sea floor is tremendous and control on drill bit pressure from a movable platform and a vibrating drill string is poor especially in the upper hundred meters. During the last decade a variety of remotely operated drill rigs have been developed, that are deployed on the sea bed and operated from standard research vessels. These developments include the BMS (Bentic Multicoring System, developed by Williamson and Associates, operated by the Japanese Mining Agency), the PROD (Portable Remotely Operated Drill, developed and operated by Benthic Geotech), the Rockdrill 2 (developed and operated by the British geological Survey) and the MeBo (German abbreviation for sea floor drill rig, developed and operated by Marum, University of Bremen). These drill rigs reach drilling depths between 15 and 100 m. For shallow drillings remotely operated drill rigs are a cost effective alternative to the services of drill ships and have the major advantage that the drilling operations are performed from a stable platform independent of any ship movements due to waves, wind or currents. Sea floor drill rigs can be deployed both in shallow waters and the deep sea. A careful site survey is required before deploying the sea floor drill rig. Slope gradient, small scale topography and soil strength are important factors when planning the deployment. The choice of drill bits and core catcher depend on the expected geology. The required drill tools are stored on one or two magazines on the drill rig. The MeBo is the only remotely operated drill rig world wide that can use wire line coring technique. This method is much faster than conventional drilling. It has the advantage that the drill string stays in the drilled hole during the entire drilling process and prevents the drilled hole from collapsing while the inner core barrels comprising the drilled core sections are hooked up inside the drill string using a wire.

Test drilling in basalts, Lalamilo area, South Kohala District, Hawaii

USGS Publications Warehouse

Teasdale, Warren E.

1980-01-01

Test drilling has determined that a downhole-percussion airhammer can be used effectively to drill basalts in Hawaii. When used in conjunction with a foam-type drilling fluid, the hammer-bit penetration rate was rapid. Continuous drill cuttings from the materials penetrated were obtained throughout the borehole except from extremely fractured or weathered basalt zones where circulation was lost or limited. Cementing of these zones as soon as encountered reduced problems of stuck tools, washouts, and loss of drill-cuttings. Supplies and logistics on the Hawaiian Islands, always a major concern, require that all anticipated drilling supplies, spare rig and tool parts, drilling muds and additives, foam, and miscellaneous hardware be on hand before starting to drill. If not, the resulting rig downtime is costly in both time and money. (USGS)

Mechanical specific energy versus depth of cut in rock cutting and drilling

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

Zhou, Yaneng; Zhang, Wu; Gamwo, Isaac

The relationship between Mechanical Specific Energy (MSE) and the Rate of Penetration (ROP), or equivalently the depth of cut per revolution, provides an important measure for strategizing a drilling operation. This study explores how MSE evolves with depth of cut, and presents a concerted effort that encompasses analytical, computational and experimental approaches. A simple model for the relationship between MSE and cutting depth is first derived with consideration of the wear progression of a circular cutter. This is an extension of Detournay and Defourny's phenomenological cutting model. Wear is modeled as a flat contact area at the bottom of amore » cutter referred to as a wear flat, and that wear flat in the past is often considered to be fixed during cutting. But during a drilling operation by a full bit that consists of multiple circular cutters, the wear flat length may increase because of various wear mechanisms involved. The wear progression of cutters generally results in reduced efficiency with either increased MSE or decreased ROP. Also, an accurate estimate of removed rock volume is found important for the evaluation of MSE. The derived model is compared with experiment results from a single circular cutter, for cutting soft rock under ambient pressure with actual depth measured through a micrometer, and for cutting high strength rock under high pressure with actual cutting area measured by a confocal microscope. Lastly, the model is employed to interpret the evolution of MSE with depth of cut for a full drilling bit under confining pressure. The general form of equation of the developed model is found to describe well the experiment data and can be applied to interpret the drilling data for a full bit.« less

Design and evaluation of a portable intra-operative unified-planning-and-guidance framework applied to distal radius fracture surgery.

PubMed

Magaraggia, Jessica; Wei, Wei; Weiten, Markus; Kleinszig, Gerhard; Vetter, Sven; Franke, Jochen; John, Adrian; Egli, Adrian; Barth, Karl; Angelopoulou, Elli; Hornegger, Joachim

2017-01-01

During a standard fracture reduction and fixation procedure of the distal radius, only fluoroscopic images are available for planning of the screw placement and monitoring of the drill bit trajectory. Our prototype intra-operative framework integrates planning and drill guidance for a simplified and improved planning transfer. Guidance information is extracted using a video camera mounted onto a surgical drill. Real-time feedback of the drill bit position is provided using an augmented view of the planning X-rays. We evaluate the accuracy of the placed screws on plastic bones and on healthy and fractured forearm specimens. We also investigate the difference in accuracy between guided screw placement versus freehand. Moreover, the accuracy of the real-time position feedback of the drill bit is evaluated. A total of 166 screws were placed. On 37 plastic bones, our obtained accuracy was [Formula: see text] mm, [Formula: see text] and [Formula: see text] in tip position and orientation (azimuth and elevation), respectively. On the three healthy forearm specimens, our obtained accuracy was [Formula: see text] mm, [Formula: see text] and [Formula: see text]. On the two fractured specimens, we attained: [Formula: see text] mm, [Formula: see text] and [Formula: see text]. When screw plans were applied freehand (without our guidance system), the achieved accuracy was [Formula: see text] mm, [Formula: see text], while when they were transferred under guidance, we obtained [Formula: see text] mm, [Formula: see text]. Our results show that our framework is expected to increase the accuracy in screw positioning and to improve robustness w.r.t. freehand placement.

Mechanical specific energy versus depth of cut in rock cutting and drilling

DOE PAGES

Zhou, Yaneng; Zhang, Wu; Gamwo, Isaac; ...

2017-12-07

The relationship between Mechanical Specific Energy (MSE) and the Rate of Penetration (ROP), or equivalently the depth of cut per revolution, provides an important measure for strategizing a drilling operation. This study explores how MSE evolves with depth of cut, and presents a concerted effort that encompasses analytical, computational and experimental approaches. A simple model for the relationship between MSE and cutting depth is first derived with consideration of the wear progression of a circular cutter. This is an extension of Detournay and Defourny's phenomenological cutting model. Wear is modeled as a flat contact area at the bottom of amore » cutter referred to as a wear flat, and that wear flat in the past is often considered to be fixed during cutting. But during a drilling operation by a full bit that consists of multiple circular cutters, the wear flat length may increase because of various wear mechanisms involved. The wear progression of cutters generally results in reduced efficiency with either increased MSE or decreased ROP. Also, an accurate estimate of removed rock volume is found important for the evaluation of MSE. The derived model is compared with experiment results from a single circular cutter, for cutting soft rock under ambient pressure with actual depth measured through a micrometer, and for cutting high strength rock under high pressure with actual cutting area measured by a confocal microscope. Lastly, the model is employed to interpret the evolution of MSE with depth of cut for a full drilling bit under confining pressure. The general form of equation of the developed model is found to describe well the experiment data and can be applied to interpret the drilling data for a full bit.« less

Standard Operating Procedure for Surface Paint Sample Collection using a Modified Wood Drill Bit with a Variable Speed Portable Electric Drill

EPA Science Inventory

This standard operating procedure (SOP) describes a new, rapid, and relatively inexpensive way to remove a precise area of paint from the substrate of building structures in preparation for quantitative analysis. This method has been applied successfully in the laboratory, as we...

30 CFR 75.1322 - Stemming boreholes

Code of Federal Regulations, 2010 CFR

2010-07-01

... water stemming bags shall be tamped to fill the entire cross sectional area of the borehole. (c... water stemming bag shall be within 1/4 of an inch of the diameter of the drill bit used to drill the borehole. (h) Water stemming bags shall be constructed of tear-resistant and flame-resistant material and...

Miniature Low-Mass Drill Actuated by Flextensional Piezo Stack

NASA Technical Reports Server (NTRS)

Sherrit, Stewart; Badescu, Mircea; Bar-Cohen, Yoseph

2010-01-01

Recent experiments with a flextensional piezoelectric actuator have led to the development of a sampler with a bit that is designed to produce and capture a full set of sample forms including volatiles, powdered cuttings, and core fragments. The flextensional piezoelectric actuator is a part of a series of devices used to amplify the generated strain from piezoelectric actuators. Other examples include stacks, bimorphs, benders, and cantilevers. These devices combine geometric and resonance amplifications to produce large stroke at high power density. The operation of this sampler/drill was demonstrated using a 3x2x1-cm actuator weighing 12 g using power of about 10-W and a preload of about 10 N. A limestone block was drilled to a depth of about 1 cm in five minutes to produce powdered cuttings. It is generally hard to collect volatiles from random surface profiles found in rocks and sediment, powdered cuttings, and core fragments. Toward the end of collecting volatiles, the actuator and the bit are covered with bellows-shaped shrouds to prevent fines and other debris from reaching the analyzer. A tube with a miniature bellows (to provide flexibility) is connected to the bit and directs the flow of the volatiles to the analyzer. Another modality was conceived where the hose is connected to the bellows wall directly to allow the capture of volatiles generated both inside and outside the bit. A wide variety of commercial bellows used in the vacuum and microwave industries can be used to design the volatiles capture mechanism. The piezoelectric drilling mechanism can potentially be operated in a broad temperature range from about-200 to less than 450 C. The actuators used here are similar to the actuators that are currently baselined to fly as part of the inlet funnel shaking mechanism design of MSL (Mars Science Laboratory). The space qualification of these parts gives this drill a higher potential for inclusion in a future mission, especially when considering its characteristics of low mass, small size, low power, and low axial loads for sampling.

Computer Simulation To Assess The Feasibility Of Coring Magma

NASA Astrophysics Data System (ADS)

Su, J.; Eichelberger, J. C.

2017-12-01

Lava lakes on Kilauea Volcano, Hawaii have been successfully cored many times, often with nearly complete recovery and at temperatures exceeding 1100oC. Water exiting nozzles on the diamond core bit face quenches melt to glass just ahead of the advancing bit. The bit readily cuts a clean annulus and the core, fully quenched lava, passes smoothly into the core barrel. The core remains intact after recovery, even when there are comparable amounts of glass and crystals with different coefficients of thermal expansion. The unique resulting data reveal the rate and sequence of crystal growth in cooling basaltic lava and the continuous liquid line of descent as a function of temperature from basalt to rhyolite. Now that magma bodies, rather than lava pooled at the surface, have been penetrated by geothermal drilling, the question arises as to whether similar coring could be conducted at depth, providing fundamentally new insights into behavior of magma. This situation is considerably more complex because the coring would be conducted at depths exceeding 2 km and drilling fluid pressures of 20 MPa or more. Criteria that must be satisfied include: 1) melt is quenched ahead of the bit and the core itself must be quenched before it enters the barrel; 2) circulating drilling fluid must keep the temperature of the coring assembling cooled to within operational limits; 3) the drilling fluid column must nowhere exceed the local boiling point. A fluid flow simulation was conducted to estimate the process parameters necessary to maintain workable temperatures during the coring operation. SolidWorks Flow Simulation was used to estimate the effect of process parameters on the temperature distribution of the magma immediately surrounding the borehole and of drilling fluid within the bottom-hole assembly (BHA). A solid model of the BHA was created in SolidWorks to capture the flow behavior around the BHA components. Process parameters used in the model include the fluid properties and temperature of magma, coolant flow rate, rotation speed, and rate of penetration (ROP). The modeling results indicate that there are combinations of process parameters that will provide sufficient cooling to enable the desired coring process in magma.

ROPEC - ROtary PErcussive Coring Drill for Mars Sample Return

NASA Technical Reports Server (NTRS)

Chu, Philip; Spring, Justin; Zacny, Kris

2014-01-01

The ROtary Percussive Coring Drill is a light weight, flight-like, five-actuator drilling system prototype designed to acquire core material from rock targets for the purposes of Mars Sample Return. In addition to producing rock cores for sample caching, the ROPEC drill can be integrated with a number of end effectors to perform functions such as rock surface abrasion, dust and debris removal, powder and regolith acquisition, and viewing of potential cores prior to caching. The ROPEC drill and its suite of end effectors have been demonstrated with a five degree of freedom Robotic Arm mounted to a mobility system with a prototype sample cache and bit storage station.

Compact drilling and sample system

NASA Technical Reports Server (NTRS)

Gillis-Smith, Greg R.; Petercsak, Doug

1998-01-01

The Compact Drilling and Sample System (CDSS) was developed to drill into terrestrial, cometary, and asteroid material in a cryogenic, vacuum environment in order to acquire subsurface samples. Although drills were used by the Apollo astronauts some 20 years ago, this drill is a fraction of the mass and power and operates completely autonomously, able to drill, acquire, transport, dock, and release sample containers in science instruments. The CDSS has incorporated into its control system the ability to gather science data about the material being drilled by measuring drilling rate per force applied and torque. This drill will be able to optimize rotation and thrust in order to achieve the highest drilling rate possible in any given sample. The drill can be commanded to drill at a specified force, so that force imparted on the rover or lander is limited. This paper will discuss the cryo dc brush motors, carbide gears, cryogenic lubrication, quick-release interchangeable sampling drill bits, percussion drilling and the control system developed to achieve autonomous, cryogenic, vacuum, lightweight drilling.

Experimental and numerical study of drill bit drop tests on Kuru granite.

PubMed

Fourmeau, Marion; Kane, Alexandre; Hokka, Mikko

2017-01-28

This paper presents an experimental and numerical study of Kuru grey granite impacted with a seven-buttons drill bit mounted on an instrumented drop test machine. The force versus displacement curves during the impact, so-called bit-rock interaction (BRI) curves, were obtained using strain gauge measurements for two levels of impact energy. Moreover, the volume of removed rock after each drop test was evaluated by stereo-lithography (three-dimensional surface reconstruction). A modified version of the Holmquist-Johnson-Cook (MHJC) material model was calibrated using Kuru granite test results available from the literature. Numerical simulations of the single drop tests were carried out using the MHJC model available in the LS-DYNA explicit finite-element solver. The influence of the impact energy and additional confining pressure on the BRI curves and the volume of the removed rock is discussed. In addition, the influence of the rock surface shape before impact was evaluated using two different mesh geometries: a flat surface and a hyperbolic surface. The experimental and numerical results are compared and discussed in terms of drilling efficiency through the mechanical specific energy.This article is part of the themed issue 'Experimental testing and modelling of brittle materials at high strain rates'. © 2016 The Author(s).

Wireline Deep Drill for the Exploration of Icy Bodies

NASA Technical Reports Server (NTRS)

Paulsen, G.; Zacny, K.; Mellerowicz, B.; Craft, J.; Bar-Cohen, Y.; Beegle, L.; Sherrit, S.; Badescu, M.; Corsetti, F.; Ibarra, Y.

2013-01-01

One of the most pressing current questions in space science is whether life has ever arisen anywhere else in the universe. Water is a critical prerequisite for all life-as-we-know-it, thus the possible exploration targets for extraterrestrial life are bodies that have or had copious liquid: Mars, Europa, and Enceladus. Due to the oxidizing nature of Mars' surface, as well as subsurface liquid water reservoirs present on Europa and Enceladus, the search for evidence of existing life must likely focus on subsurface locations, at depths sufficient to support liquid water or retain biologic signatures. To address these questions, an Auto-Gopher sampler has been developed that is a wireline type drill. This drill is suspended on a tether and its motors and mechanisms are built into a tube that ends with a coring bit. The tether provides the mechanical connection to a rover/lander on a surface as well as power and data communication. Upon penetrating to a target depth, the drill is retracted from the borehole, the core is deposited into a sample transfer system, and the drill is lowered back into the hole. Wireline operation sidesteps one of the major drawbacks of traditional continuous drill string systems by obviating the need for multiple drill sections, which add significantly to the mass and the complexity of the system (i.e. penetration rate was 40 cm per hour). Drilling to 2 meter depth and recovering of cores every 10 cm took a total time of 15 hours (a single step of drilling 10 cm and retrieving the core was 45 minutes). Total energy to reach the 2 m depth was 500 Whr. The Weight on Bit was limited to less than 70 Newton. The core recovery was 100%.

Experimental analysis of drilling process in cortical bone.

PubMed

Wang, Wendong; Shi, Yikai; Yang, Ning; Yuan, Xiaoqing

2014-02-01

Bone drilling is an essential part in orthopaedics, traumatology and bone biopsy. Prediction and control of drilling forces and torque are critical to the success of operations involving bone drilling. This paper studied the drilling force, torque and drilling process with automatic and manual drill penetrating into bovine cortical bone. The tests were performed on a drilling system which is used to drill and measure forces and torque during drilling. The effects of drilling speed, feed rate and drill bit diameter on force and torque were discussed separately. The experimental results were proven to be in accordance with the mathematic expressions introduced in this paper. The automatic drilling saved drilling time by 30-60% in the tested range and created less vibration, compared to manual drilling. The deviation between maximum and average force of the automatic drilling was 5N but 25N for manual drilling. To conclude, using the automatic method has significant advantages in control drilling force, torque and drilling process in bone drilling. Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.

Seismic Stability Evaluation of Folsom Dam and Reservoir Project. Report 4. Mormon Island Auxiliary Dam. Phase 1

DTIC Science & Technology

1990-12-01

soundings were made with a Felcon bit which is a 3- web crowd-in bit for 6-5/8-in. casing but has an enlarged diameter near the bit (7-1/4-in. OD) and...Fed Figure 40. Becker Htammer drilling rig Figure 41. Three- web crowd-in Felcon bit for open-bit penetration testing and sampling, and eight-tooth crowd...0 000 l’ U 900 o US U 0 m wIX = r = 0 c 1 ,- 2 cc w > uW~- 0 .4-t)t UO: >. N m Cj U 0 (I uuja:o o o oH 00 U~~ u C1 to F-4 m 0 0 V) V) 0) NN 00_

Drilling Holes in Graphite/Epoxy

NASA Technical Reports Server (NTRS)

Minlionica, Ronald

1987-01-01

Relatively long-lived bit produces high-quality holes. Effective combination of cutting-tool design, feed, and speed determined for drilling 3/16-and-1/4-in. (0.48-and 0.65-cm) diameter holes in 0.18 in. (0.46cm) thick GM3013A or equivalent graphite/epoxy corrugated spar without backup material and without coolant. Developed to produce holes in blind areas, optimal techniques yielded holes of high quality, with minimal or acceptable delamination and/or fiber extension on drill-exit side.

Design of a water jet drill for development of geothermal resources. Annual progress report, June 1, 1976--May 31, 1977

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

Not Available

1977-05-31

Research was expanded to the drilling of crystalline rock. Advance rates of 40 inches per minute have been achieved at 16,000 psi, 10 gpm flow rate in a 30,000 psi compressive strength rock using the water alone as the drilling mechanism. The quality of the hole achieved as the jet drilled a variety of rock was found to vary and a hydromechanical drilling bit, combining high pressure water jets with roller cones, has been developed. A field drilling unit has been tested and modified to allow the drilling of holes to 3/sup 1///sub 2/ inch diameter using the hydromechanical drill.more » Preliminary work on the development of a cavitation test for rock is also included.« less

Application of an enhanced discrete element method to oil and gas drilling processes

NASA Astrophysics Data System (ADS)

Ubach, Pere Andreu; Arrufat, Ferran; Ring, Lev; Gandikota, Raju; Zárate, Francisco; Oñate, Eugenio

2016-03-01

The authors present results on the use of the discrete element method (DEM) for the simulation of drilling processes typical in the oil and gas exploration industry. The numerical method uses advanced DEM techniques using a local definition of the DEM parameters and combined FEM-DEM procedures. This paper presents a step-by-step procedure to build a DEM model for analysis of the soil region coupled to a FEM model for discretizing the drilling tool that reproduces the drilling mechanics of a particular drill bit. A parametric study has been performed to determine the model parameters in order to maintain accurate solutions with reduced computational cost.

Hard-rock jetting. Part 2. Rock type decides jetting economics

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

Pols, A.C.

1977-02-07

In Part 2, Koninklijke Shell Exploratie en Produktie Laboratorium presents the results of jet-drilling laminated formations. Shell concludes that (1) hard, laminated rock cannot be jet-drilled satisfactorily without additional mechanical cutting aids, (2) the increase in penetration rate with bit-pressure drop is much lower for impermeable rock than it is for permeable rock, (3) drilling mud can have either a positive or a negative effect on penetration rate in comparison with water, depending on the material drilled, and (4) hard, isotropic, sedimentary, impermeable rock can be drilled using jets at higher rates than with conventional means. However, jetting becomes profitablemore » only in the case of expensive rigs.« less

Laboratory Investigations for the Role of Flushing Media in Diamond Drilling of Marble

NASA Astrophysics Data System (ADS)

Bhatnagar, A.; Khandelwal, Manoj; Rao, K. U. M.

2011-05-01

Marble is used as a natural stone for decorative purposes from ages. Marble is a crystalline rock, composed predominantly of calcite, dolomite or serpentine. The presence of impurities imparts decorative pattern and colors. The diamond-based operations are extensively used in the mining and processing of marble. Marble is mined out in the form of blocks of cuboids shape and has to undergo extensive processing to make it suitable for the end users. The processing operation includes slabbing, sizing, polishing, etc. Diamond drilling is also commonly used for the exploration of different mineral deposits throughout the world. In this paper an attempt has been made to enhance the performance of diamond drilling on marble rocks by adding polyethylene-oxide (PEO) in the flushing water. The effect of PEO added with the drilling water was studied by varying different machine parameters and flushing media concentration in the laboratory. The responses were rate of penetration and torque at bit-rock interface. Different physico-mechanical properties of marble were also determined. It was found that flushing water added with PEO can substantially enhance the penetration rates and reduce the torque developed at the bit-rock interface as compared to plain flushing water.

Berengario's drill: origin and inspiration.

PubMed

Chorney, Michael A; Gandhi, Chirag D; Prestigiacomo, Charles J

2014-04-01

Craniotomies are among the oldest neurosurgical procedures, as evidenced by early human skulls discovered with holes in the calvaria. Though devices change, the principles to safely transgress the skull are identical. Modern neurosurgeons regularly use electric power drills in the operating theater; however, nonelectric trephining instruments remain trusted by professionals in certain emergent settings in the rare instance that an electric drill is unavailable. Until the late Middle Ages, innovation in craniotomy instrumentation remained stunted without much documented redesign. Jacopo Berengario da Carpi's (c. 1457-1530 CE) text Tractatus de Fractura Calvae sive Cranei depicts a drill previously unseen in a medical volume. Written in 1518 CE, the book was motivated by defeat over the course of Lorenzo II de'Medici's medical care. Berengario's interchangeable bit with a compound brace ("vertibulum"), known today as the Hudson brace, symbolizes a pivotal device in neurosurgery and medical tool design. This drill permitted surgeons to stock multiple bits, perform the craniotomy faster, and decrease equipment costs during a period of increased incidence of cranial fractures, and thus the need for craniotomies, which was attributable to the introduction of gunpowder. The inspiration stemmed from a school of thought growing within a population of physicians trained as mathematicians, engineers, and astrologers prior to entering the medical profession. Berengario may have been the first to record the use of such a unique drill, but whether he invented this instrument or merely adapted its use for the craniotomy remains clouded.

Subterranean drilling and in situ treatment of wastes using a contamination control system and methods relating thereto

DOEpatents

Jessmore, James J.; Loomis, Guy G.; Pettet, Mark C.; Flyckt, Melissa C.

2004-09-28

Systems and methods relating to subterranean drilling while maintaining containment of any contaminants released during the drilling. A thrust block installed over a zone of interest provides an overflow space for retaining any contaminants and excess sealant returns. Negative air pressure may be maintained in the overflow space by a ventilation system. Access ports in the thrust block seal the overflow space from the surrounding environment with a membrane seal. A flexible sack seal in the access port may be connected to a drill shroud prior to drilling, providing containment during drilling after the drill bit penetrates the membrane seal. The drill shroud may be adapted to any industry standard drilling rig and includes a connection conduit for connecting to the flexible sack seal and a flexible enclosure surrounding the drill shaft and of a length to accommodate full extension thereof. Upon withdrawal, the sack seal may be closed off and separated, maintaining containment of the overflow space and the drill shroud.

Fluorocarbon Contamination from the Drill on the Mars Science Laboratory: Potential Science Impact on Detecting Martian Organics by Sample Analysis at Mars (SAM)

NASA Technical Reports Server (NTRS)

Eigenbrode, J. L.; McAdam, A.; Franz, H.; Freissinet, C.; Bower, H.; Floyd, M.; Conrad, P.; Mahaffy, P.; Feldman, J.; Hurowitz, J.;

Parameters affecting mechanical and thermal responses in bone drilling: A review.

PubMed

Lee, JuEun; Chavez, Craig L; Park, Joorok

2018-04-11

Surgical bone drilling is performed variously to correct bone fractures, install prosthetics, or for therapeutic treatment. The primary concern in bone drilling is to extract donor bone sections and create receiving holes without damaging the bone tissue either mechanically or thermally. We review current results from experimental and theoretical studies to investigate the parameters related to such effects. This leads to a comprehensive understanding of the mechanical and thermal aspects of bone drilling to reduce their unwanted complications. This review examines the important bone-drilling parameters of bone structure, drill-bit geometry, operating conditions, and material evacuation, and considers the current techniques used in bone drilling. We then analyze the associated mechanical and thermal effects and their contributions to bone-drilling performance. In this review, we identify a favorable range for each parameter to reduce unwanted complications due to mechanical or thermal effects. Copyright © 2018 Elsevier Ltd. All rights reserved.

Optimisation of the geometry of the drill bit and process parameters for cutting hybrid composite/metal structures in new aircrafts

NASA Astrophysics Data System (ADS)

Isbilir, Ozden

Owing to their desirable strength-to-weight characteristics, carbon fibre reinforced polymer composites have been favourite materials for structural applications in different industries such as aerospace, transport, sports and energy. They provide a weight reduction in whole structure and consequently decrease fuel consumption. The use of lightweight materials such as titanium and its alloys in modern aircrafts has also increased significantly in the last couple of decades. Titanium and its alloys offer high strength/weight ratio, high compressive and tensile strength at high temperatures, low density, excellent corrosion resistance, exceptional erosion resistance, superior fatigue resistance and relatively low modulus of elasticity. Although composite/metal hybrid structures are increasingly used in airframes nowadays, number of studies regarding drilling of composite/metal stacks is very limited. During drilling of multilayer materials different problems may arise due to very different attributes of these materials. Machining conditions of drilling such structures play an important role on tool wear, quality of holes and cost of machining.. The research work in this thesis is aimed to investigate drilling of CFRP/Ti6Al4V hybrid structure and to optimize process parameters and drill geometry. The research work consist complete experimental study including drilling tests, in-situ and post measurements and related analysis; and finite element analysis including fully 3-D finite element models. The experimental investigations focused on drilling outputs such as thrust force, torque, delamination, burr formation, surface roughness and tool wear. An algorithm was developed to analyse drilling induced delamination quantitatively based on the images. In the numerical analysis, novel 3-D finite element models of drilling of CFRP, Ti6Al4V and CFRP/Ti6Al4V hybrid structure were developed with the use of 3-D complex drill geometries. A user defined subroutine was developed to model material and failure behaviour of CFRP. The effects of process parameters on drilling outputs have been investigated and compared with the experimental results. The influences of drill bit geometries have been simulated in this study..

Ejector subassembly for dual wall air drilling

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

Kolle, J.J.

1996-09-01

The dry drilling system developed for the Yucca Mountain Site Characterization Project incorporates a surface vacuum system to prevent drilling air and cuttings from contaminating the borehole wall during coring operations. As the drilling depth increases, however there is a potential for borehole contamination because of the limited volume of air which can be removed by the vacuum system. A feasibility analysis has shown that an ejector subassembly mounted in the drill string above the core barrel could significantly enhance the depth capacity of the dry drilling system. The ejector subassembly would use a portion of the air supplied tomore » the core bit to maintain a vacuum on the hole bottom. The results of a design study including performance testing of laboratory scale ejector simulator are presented here.« less

First Drilled Sample on Mars Since 2016

NASA Image and Video Library

2018-05-23

NASA's Curiosity rover successfully drilled a hole 2 inches (5.1 centimeters) deep in a target called "Duluth" on May 20, 2018. The hole is about .6 inches (1.6 centimeters) across. It was the first rock sample captured by the drill since October 2016. A mechanical issue took the drill offline in December 2016. Engineers at NASA's Jet Propulsion Laboratory in Pasadena, California, had to innovate a new way for the rover to drill in order to restore this ability. The new technique, called Feed Extended Drilling (FED) keeps the drill's bit extended out past two stabilizer posts that were originally used to steady the drill against Martian rocks. It lets Curiosity drill using the force of its robotic arm, a little more like a human would while drilling into a wall at home. This image was taken by Curiosity's Mast Camera (Mastcam) on Sol 2057. It has been white balanced and contrast-enhanced. https://photojournal.jpl.nasa.gov/catalog/PIA22325

High-temperature seals and lubricants for geothermal rock bits. Final report

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

Hendrickson, R.R.; Winzenried, R.W.; Jones A.H.

1981-04-01

High temperature seals (elastomeric and mechanical) and lubricants were developed specifically for journal-type rock bits to be used in geothermal well drilling. Results at simulated downhole conditions indicate that five selected elastomeric seals (L'Garde No. 267, Utex Nos. 227, 231 and HTCR, and Sandia Glow Discharge Coated Viton) are capable of 288/sup 0/C (500/sup 0/F) service. Two prototype mechanical seals did not achieve the life determined for the elastomeric seals. Six lubricants (Pacer PLX-024 oil, PLX-043 oil, PLX-045 oil, Geobond Oil, and Geobond Grease) demonstrated 316/sup 0/C (600/sup 0/F) capability. Recommendation is made for full-scale simulated geothermal drilling tests utilizingmore » the improved elastomeric seals and lubricants.« less

A SMALL-ANGLE DRILL-HOLE WHIPSTOCK

DOEpatents

Nielsen, D.E.; Olsen, J.L.; Bennett, W.P.

1963-01-29

A small angle whipstock is described for accurately correcting or deviating a drill hole by a very small angle. The whipstock is primarily utilized when drilling extremely accurate, line-of-slight test holes as required for diagnostic studies related to underground nuclear test shots. The invention is constructed of a length of cylindrical pipe or casing, with a whipstock seating spike extending from the lower end. A wedge-shaped segment is secured to the outer circumference of the upper end of the cylinder at a position diametrically opposite the circumferential position of the spike. Pin means are provided for affixing the whipstock to a directional drill bit and stem to alloy orienting and setting the whipstock properly in the drill hole. (AEC)

Testing and Development of a Percussive Augmenter for Rotary Drills

NASA Technical Reports Server (NTRS)

Donnelly, Christopher; Bar-Cohen, Yoseph; Chang, Zensheu; Badescu, Mircea; Sherrit, Stewart

2011-01-01

Hammering drills are effective in fracturing the drilled medium while rotary drills remove cuttings. The combination provides a highly effective penetration mechanism. Piezoelectric actuators were integrated into an adapter to produce ultrasonic percussion; augmenting rotary drilling. The drill is capable of operating at low power, low applied force and, with proper tuning, low noise. These characteristics are of great interest for future NASA missions and the construction/remodeling industry. The developed augmenter connects a commercially available drill and bit and was tested to demonstrate its capability. Input power to the drill was read using a multimeter and the augmenter received a separate input voltage. The drive frequency of the piezoelectric actuator was controlled by a hill climb algorithm that optimizes and records average power usage to operate the drill at resonating frequency. Testing the rotary drill and augmenter across a range of combinations with total power constant at 160 Watts has shown results in concrete and limestone samples that are as good as or better than the commercial drill. The drill rate was increased 1.5 to over 10 times when compared to rotation alone.

Coated carbide drill performance under soluble coconut oil lubricant and nanoparticle enhanced MQL in drilling AISI P20

NASA Astrophysics Data System (ADS)

Jamil, N. A. M.; Azmi, A. I.; Fairuz, M. A.

2016-02-01

This research experimentally investigates the performance of a TiAlN coated carbide drill bit in drilling AISI P20 through two different kinds of lubricants, namely; soluble coconut oil (SCO) and nanoparticle-enhanced coconut oil (NECO) under minimum quantity lubrication system. The tool life and tool wear mechanism were studied using various cutting speeds of 50, 100 and 150 m/min with a constant feed of 0.01 mm/rev. Since the flank wear land was not regular along the cutting edge, the average flank wear (VB) was measured at several points using image analysis software. The drills were inspected using a scanning electron microscope to further elucidate the wear mechanism. The result indicates that drilling with the nanoparticle- enhanced lubricant was better in resisting the wear and improving the drill life to some extent

An electrical conductivity inspection methodology of polycrystalline diamond cutters

NASA Astrophysics Data System (ADS)

Bogdanov, G.; Wiggins, J.; Bertagnolli, K.; Ludwig, R.

2012-05-01

The polycrystalline diamond cutter (PDC) is widely used in oil and gas drilling operations. It is manufactured by sintering diamond powder onto a tungsten carbide substrate at 6 GPa and 1500 C. During sintering, molten cobalt from the substrate infiltrates the diamond table. The residual metal content correlates with cutter performance. We present an instrument that employs electrical impedance tomography capable of imaging the 3D metal content distribution in the diamond table. These images can be used to predict cutter performance as well as detect flaws.

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

Gavignet, A.A.; Sobey, I.J.

At present, drilling of highly deviated wells is complicated by the possibility of the formation of a thick bed of cuttings at low flow rates. The bed of cuttings can cause large torque loads on drill pipe and can fall back around the bit resulting in a stuck bit. Previous investigators have made experimental observations which show that bed formation is characterized by a relatively rapid increase in bed thickness as either the flow rate is lowered past some critical value, or as the deviation from the vertical increases. The authors present a simple model which explains these observations. Themore » model shows that the bed thickness is controlled by the interfacial stress caused by the different velocities of the mud and the cuttings layer. The results confirm previous observations that bed formation is relatively insensitive to mud rheology. Eccentricity of the drill pipe in the hole is an important factor. The model is used to determine critical flow rate needed to prevent the formation of a thick bed of cuttings and the inclination, hole size and rate of penetration are varied.« less

NETL Extreme Drilling Laboratory Studies High Pressure High Temperature Drilling Phenomena

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

Lyons, K.D.; Honeygan, S.; Moroz, T.H.

2008-12-01

The U.S. Department of Energy's National Energy Technology Laboratory (NETL) established the Extreme Drilling Laboratory to engineer effective and efficient drilling technologies viable at depths greater than 20,000 ft. This paper details the challenges of ultradeep drilling, documents reports of decreased drilling rates as a result of increasing fluid pressure and temperature, and describes NETL's research and development activities. NETL is invested in laboratory-scale physical simulation. Its physical simulator will have capability of circulating drilling fluids at 30,000 psi and 480°F around a single drill cutter. This simulator is not yet operational; therefore, the results will be limited to themore » identification of leading hypotheses of drilling phenomena and NETL's test plans to validate or refute such theories. Of particular interest to the Extreme Drilling Laboratory's studies are the combinatorial effects of drilling fluid pressure, drilling fluid properties, rock properties, pore pressure, and drilling parameters, such as cutter rotational speed, weight on bit, and hydraulics associated with drilling fluid introduction to the rock-cutter interface. A detailed discussion of how each variable is controlled in a laboratory setting will be part of the conference paper and presentation.« less

Measurement of distances between anatomical structures using a translating stage with mounted endoscope

NASA Astrophysics Data System (ADS)

Kahrs, Lueder A.; Blachon, Gregoire S.; Balachandran, Ramya; Fitzpatrick, J. Michael; Labadie, Robert F.

2012-02-01

During endoscopic procedures it is often desirable to determine the distance between anatomical features. One such clinical application is percutaneous cochlear implantation (PCI), which is a minimally invasive approach to the cochlea via a single, straight drill path and can be achieved accurately using bone-implanted markers and customized microstereotactic frame. During clinical studies to validate PCI, traditional open-field cochlear implant surgery was performed and prior to completion of the surgery, a customized microstereotactic frame designed to achieve the desired PCI trajectory was attached to the bone-implanted markers. To determine whether this trajectory would have safely achieved the target, a sham drill bit is passed through the frame to ensure that the drill bit would reach the cochlea without damaging vital structures. Because of limited access within the facial recess, the distances from the bit to anatomical features could not be measured with calipers. We hypothesized that an endoscope mounted on a sliding stage that translates only along the trajectory, would provide sufficient triangulation to accurately measure these distances. In this paper, the design, fabrication, and testing of such a system is described. The endoscope is mounted so that its optical axis is approximately aligned with the trajectory. Several images are acquired as the stage is moved, and threedimensional reconstruction of selected points allows determination of distances. This concept also has applicability in a large variety of rigid endoscopic interventions including bronchoscopy, laparoscopy, and sinus endoscopy.

The Auto-Gopher Deep Drill

NASA Technical Reports Server (NTRS)

Badescu, Mircea

2014-01-01

Subsurface penetration by coring, drilling or abrading is of great importance for a large number of space and earth applications. An Ultrasonic/Sonic Drill/Corer (USDC) has been in development at JPL's Nondestructive Evaluation and Advanced Actuators (NDEAA) lab as an adaptable tool for many of these applications. The USDC uses a novel drive mechanism to transform the high frequency ultrasonic or sonic vibrations of the tip of a horn into a lower frequency sonic hammering of a drill bit through an intermediate free-flying mass. The USDC device idea has been implemented at various scales from handheld drills to large diameter coring devices. A series of computer programs that model the function and performance of the USDC device were developed and were later integrated into an automated modeling package. The USDC has also evolved from a purely hammering drill to a rotary hammer drill as the design requirements increased form small diameter shallow drilling to large diameter deep coring. A synthesis of the Auto-Gopher development is presented in this paper.

An experimental system for coiled tubing partial underbalanced drilling (CT-PUBD) technique

NASA Astrophysics Data System (ADS)

Shi, H. Z.; Ji, Z. S.; Zhao, H. Q.; Chen, Z. L.; Zhang, H. Z.

2018-05-01

To improve the rate of penetration (ROP) in hard formations, a new high-speed drilling technique called Coiled Tubing Partial Underbalanced Drilling (CT-PUBD) is proposed. This method uses a rotary packer to realize an underbalanced condition near the bit by creating a micro-annulus and an overbalanced condition at the main part of the annulus. A new full-scale laboratory experimental system is designed and set up to study the hydraulic characteristics and drilling performance of this method. The system is composed of a drilling system, circulation system, and monitor system, including three key devices, namely, cuttings discharge device, rotary packer, and backflow device. The experimental results showed that the pressure loss increased linearly with the flow rate of the drilling fluid. The high drilling speed of CT-PUBD proved it a better drilling method than the conventional drilling. The experimental system may provide a fundamental basis for the research of CT-PUBD, and the results proved that this new method is feasible in enhancing ROP and guaranteeing the drilling safety.

Temperature Prediction Model for Bone Drilling Based on Density Distribution and In Vivo Experiments for Minimally Invasive Robotic Cochlear Implantation.

PubMed

Feldmann, Arne; Anso, Juan; Bell, Brett; Williamson, Tom; Gavaghan, Kate; Gerber, Nicolas; Rohrbach, Helene; Weber, Stefan; Zysset, Philippe

2016-05-01

Surgical robots have been proposed ex vivo to drill precise holes in the temporal bone for minimally invasive cochlear implantation. The main risk of the procedure is damage of the facial nerve due to mechanical interaction or due to temperature elevation during the drilling process. To evaluate the thermal risk of the drilling process, a simplified model is proposed which aims to enable an assessment of risk posed to the facial nerve for a given set of constant process parameters for different mastoid bone densities. The model uses the bone density distribution along the drilling trajectory in the mastoid bone to calculate a time dependent heat production function at the tip of the drill bit. Using a time dependent moving point source Green's function, the heat equation can be solved at a certain point in space so that the resulting temperatures can be calculated over time. The model was calibrated and initially verified with in vivo temperature data. The data was collected in minimally invasive robotic drilling of 12 holes in four different sheep. The sheep were anesthetized and the temperature elevations were measured with a thermocouple which was inserted in a previously drilled hole next to the planned drilling trajectory. Bone density distributions were extracted from pre-operative CT data by averaging Hounsfield values over the drill bit diameter. Post-operative [Formula: see text]CT data was used to verify the drilling accuracy of the trajectories. The comparison of measured and calculated temperatures shows a very good match for both heating and cooling phases. The average prediction error of the maximum temperature was less than 0.7 °C and the average root mean square error was approximately 0.5 °C. To analyze potential thermal damage, the model was used to calculate temperature profiles and cumulative equivalent minutes at 43 °C at a minimal distance to the facial nerve. For the selected drilling parameters, temperature elevation profiles and cumulative equivalent minutes suggest that thermal elevation of this minimally invasive cochlear implantation surgery may pose a risk to the facial nerve, especially in sclerotic or high density mastoid bones. Optimized drilling parameters need to be evaluated and the model could be used for future risk evaluation.

Casing window milling with abrasive fluid jet

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

Vestavik, O.M.; Fidtje, T.H.; Faure, A.M.

1995-12-31

Methods for through tubing re-entry drilling of multilateral wells has a large potential for increasing hydrocarbon production and total recovery. One of the bottle-necks of this technology is initiation of the side-track by milling a window in the casing downhole. A new approach to this problem has been investigated in a joint industry project. An experimental set-up has been built for milling a 4 inch window in a 7 inch steel casing at surface in the laboratory. A specially designed bit developed at RIF using abrasive jet cutting technology has been used for the window milling. The bit has anmore » abrasive jet beam which is always directed in the desired side-track direction, even if the bit is rotating uniformly. The bit performs the milling with a combined mechanical and hydraulic jet action. The method has been successfully demonstrated. The experiments has shown that the window milling can be performed with very low WOB and torque, and that only small side forces are required to perform the operation. Casing milling has been performed without a whipstock, a cement plug has been the only support for the tool. The tests indicate that milling operations can be performed more efficiently with less time and costs than what is required with conventional techniques. However, the method still needs some development of the downhole motor for coiled tubing applications. The method can be used both for milling and drilling giving the advantage of improved rate of penetration, improved bit life and increased horizontal reach. The method is planned to be demonstrated downhole in the near future.« less

Experimental system for drilling simulated lunar rock in ultrahigh vacuum

NASA Technical Reports Server (NTRS)

Roepke, W. W.

1975-01-01

An experimental apparatus designed for studying drillability of hard volcanic rock in a simulated lunar vacuum of 5 x 10 to the minus 10th power torr is described. The engineering techniques used to provide suitable drilling torque inside the ultrahigh vacuum chamber while excluding all hydrocarbon are detailed. Totally unlubricated bearings and gears were used to better approximate the true lunar surface conditions within the ultrahigh vacuum system. The drilling system has a starting torque of 30 in-lb with an unloaded running torque of 4 in-lb. Nominal torque increase during drilling is 4.5 in-lb or a total drilling torque of 8.5 in-lb with a 100-lb load on the drill bit at 210 rpm. The research shows conclusively that it is possible to design operational equipment for moderate loads operating under UHV conditions without the use of sealed bearings or any need of lubricants whatsoever.

Intraosseous Heat Generation During Osteotomy Performed Freehand and Through Template With an Integrated Metal Guide Sleeve: An In Vitro Study.

PubMed

Barrak, Ibrahim; Joób-Fancsaly, Árpád; Braunitzer, Gábor; Varga, Endre; Boa, Kristóf; Piffkó, József

2018-06-01

To investigate drill wear and consequent intraosseous temperature elevation during freehand and guided bone drilling, with attention to the effect of metal-on-metal contact during guided drilling. Osteotomies were performed on bovine ribs, with 2.0 mm diameter stainless steel drill bits of the SMART Guide System, under 3 sterilization protocols, at 800, 1200, 1500, and 2000 rpm. Sterilization was performed after every 3 drilling. Temperature was measured after every 30 drilling. The studied contributing factors had a cumulative effect, and each contributed significantly to temperature elevation. Whether guide use led to a near-necrotic (47°C) temperature increment depended largely on the applied sterilization protocol. The metal sleeve is a significant contributing factor to heat generation during guided osteotomy, but its effect can be offset by keeping the other studied factors under control.

Drilling, Coring and Sampling Using Piezoelectric Actuated Mechanisms: From the USDC to a Piezo-Rotary-Hammer Drill

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoseph; Sherrit, Stewart; Badescu, Mircea; Bao, Xiaoqi

2012-01-01

NASA exploration missions are increasingly including sampling tasks but with the growth in engineering experience (particularly, Phoenix Scout and MSL) it is now very much recognized that planetary drilling poses many challenges. The difficulties grow significantly with the hardness of sampled material, the depth of drilling and the harshness of the environmental conditions. To address the requirements for samplers that could be operated at the conditions of the various bodies in the solar system, a number of piezoelectric actuated drills and corers were developed by the Advanced Technologies Group of JPL. The basic configuration that was conceived in 1998 is known as the Ultrasonic/Sonic Driller/Corer (USDC), and it operates as a percussive mechanism. This drill requires as low preload as 10N (important for operation at low gravity) allowing to operate with as low-mass device as 400g, use an average power as low as 2- 3W and drill rocks as hard as basalt. A key feature of this drilling mechanism is the use of a free-mass to convert the ultrasonic vibrations generated by piezoelectric stack to sonic impacts on the bit. Using the versatile capabilities f the USDC led to the development of many configurations and device sizes. Significant improvement of the penetration rate was achieved by augmenting the hammering action by rotation and use of a fluted bit to remove cuttings. To reach meters deep in ice a wireline drill was developed called the Ultrasonic/Sonic Gopher and it was demonstrated in 2005 to penetrate about 2-m deep at Antarctica. Jointly with Honeybee Robotics, this mechanism is currently being modified to incorporate rotation and inchworm operation forming Auto-Gopher to reach meters deep in rocks. To take advantage of the ability of piezoelectric actuators to operate over a wide temperatures range, piezoelectric actuated drills were developed and demonstrated to operate at as cold as -200oC and as hot as 500oC. In this paper, the developed mechanisms will be reviewed and discussed including the configurations, capabilities, and challenges.

Effects of bone drilling on local temperature and bone regeneration: an in vivo study.

PubMed

Karaca, Faruk; Aksakal, Bünyamin; Köm, Mustafa

2014-01-01

The aim of this study was to examine the influence of bone drilling on local bone temperature and bone regeneration and determine optimal drilling speed and pressure in an animal model. The study included 12 skeletally mature New Zealand white rabbits, weighing between 2.8 to 3.2 kg. Rabbits were divided into 2 groups and euthanized at the end of Day 21 (Group A) and Day 42 (Group B). The same drilling protocol was used in both groups. Three drill holes with different pressure (5, 10 and 20 N) were made in each rabbit tibias using 3 different rotational drill speeds (230, 370 and 570 rpm). During drilling, local temperature was recorded. Rabbit tibia underwent histopathological exam for bone regeneration. Bone temperature was affected by drilling time and depth. Lower drill speeds reduced the bone temperature and revealed better bone regeneration when compared to the drilled bones at higher drill speeds. Titanium boron nitride coating on the drill bits had no significant effects on bone temperature and structure. Bone regeneration was superior in Group B rabbits that had drilling at 230 rpm and 20 N. Our results suggested that lower drilling speed with higher pressure is necessary for better bone regeneration. The optimal drilling speed is 230 rpm and optimal drilling pressure 20 N.

Rolling-Tooth Core Breakoff and Retention Mechanism

NASA Technical Reports Server (NTRS)

Badescu, Mircea; Bickler, Donald B.; Sherrit, Stewart; Bar-Cohen, Yoseph; Bao, Xiaoqi; Hudson, Nicolas H.

2011-01-01

Sampling cores requires the controlled breakoff of the core at a known location with respect to the drill end. An additional problem is designing a mechanism that can be implemented at a small scale that is robust and versatile enough to be used for a variety of core samples. This design consists of a set of tubes (a drill tube and an inner tube) and a rolling element (rolling tooth). An additional tube can be used as a sample tube. The drill tube and the inner tube have longitudinal holes with the axes offset from the axis of each tube. The two eccentricities are equal. The inner tube fits inside the drill tube, and the sample tube fits inside the inner tube. While drilling, the two tubes are positioned relative to each other such that the sample tube is aligned with the drill tube axis and core. The drill tube includes teeth and flutes for cuttings removal. The inner tube includes, at the base, the rolling element implemented as a wheel on a shaft in an eccentric slot. An additional slot in the inner tube and a pin in the drill tube limit the relative motion of the two tubes. While drilling, the drill assembly rotates relative to the core and forces the rolling tooth to stay hidden in the slot along the inner tube wall. When the drilling depth has been reached, the drill bit assembly is rotated in the opposite direction, and the rolling tooth is engaged and penetrates into the core. Depending on the strength of the created core, the rolling tooth can score, lock the inner tube relative to the core, start the eccentric motion of the inner tube, and break the core. The tooth and the relative position of the two tubes can act as a core catcher or core-retention mechanism as well. The design was made to fit the core and hole parameters produced by an existing bit; the parts were fabricated and a series of demonstration tests were performed. This invention is potentially applicable to sample return and in situ missions to planets such as Mars and Venus, to moons such as Titan and Europa, and to comets. It is also applicable to terrestrial applications like forensic sampling and geological sampling in the field.

Justification of the Shape of a Non-Circular Cross-Section for Drilling With a Roller Cutter

NASA Astrophysics Data System (ADS)

Buyalich, Gennady; Husnutdinov, Mikhail

2017-11-01

The parameters of the shape of non-circular cross-section affect not only the process of blasting, but also the design of the tool and the process of drilling as well. In the conditions of open-pit mining, it is reasonable to use a roller cutter to produce a non-circular cross-section of blasting holes. With regard to the roller cutter, the impact of the cross-section shape on the oscillations of the axial force arising upon its rotation is determined. It is determined that a polygonal shape with rounded comers of the borehole walls connections and their convex shape, which ensures a smaller range of the total axial force and the torque deflecting the bit from the axis of its rotation is the rational form of the non-circular cross-section of the borehole in terms of bit design. It has been shown that the ratio of the number of cutters to the number of borehole corners must be taken into account when justifying the shape of the cross-section, both from the point of view of the effectiveness of the explosion action and from the point of view of the rational design of the bit.

Investigation into the use of smartphone as a machine vision device for engineering metrology and flaw detection, with focus on drilling

NASA Astrophysics Data System (ADS)

Razdan, Vikram; Bateman, Richard

2015-05-01

This study investigates the use of a Smartphone and its camera vision capabilities in Engineering metrology and flaw detection, with a view to develop a low cost alternative to Machine vision systems which are out of range for small scale manufacturers. A Smartphone has to provide a similar level of accuracy as Machine Vision devices like Smart cameras. The objective set out was to develop an App on an Android Smartphone, incorporating advanced Computer vision algorithms written in java code. The App could then be used for recording measurements of Twist Drill bits and hole geometry, and analysing the results for accuracy. A detailed literature review was carried out for in-depth study of Machine vision systems and their capabilities, including a comparison between the HTC One X Android Smartphone and the Teledyne Dalsa BOA Smart camera. A review of the existing metrology Apps in the market was also undertaken. In addition, the drilling operation was evaluated to establish key measurement parameters of a twist Drill bit, especially flank wear and diameter. The methodology covers software development of the Android App, including the use of image processing algorithms like Gaussian Blur, Sobel and Canny available from OpenCV software library, as well as designing and developing the experimental set-up for carrying out the measurements. The results obtained from the experimental set-up were analysed for geometry of Twist Drill bits and holes, including diametrical measurements and flaw detection. The results show that Smartphones like the HTC One X have the processing power and the camera capability to carry out metrological tasks, although dimensional accuracy achievable from the Smartphone App is below the level provided by Machine vision devices like Smart cameras. A Smartphone with mechanical attachments, capable of image processing and having a reasonable level of accuracy in dimensional measurement, has the potential to become a handy low-cost Machine vision system for small scale manufacturers, especially in field metrology and flaw detection.

Recovery and Lithologic Analysis of Sediment from Hole UT-GOM2-1-H002, Green Canyon 955, Northern Gulf of Mexico

NASA Astrophysics Data System (ADS)

Kinash, N.; Cook, A.; Sawyer, D.; Heber, R.

2017-12-01

In May 2017 the University of Texas led a drilling and pressure coring expedition in the northern Gulf of Mexico, UT-GOM2-01. The holes were located in Green Canyon Block 955, where the Gulf of Mexico Joint Industry Project Leg II identified an approximately 100m thick hydrate-filled course-grained levee unit in 2009. Two separate wells were drilled into this unit: Holes H002 and H005. In Hole H002, a cutting shoe drill bit was used to collect the pressure cores, and only 1 of the 8 cores collected was pressurized during recovery. The core recovery in Hole H002 was generally poor, about 34%, while the only pressurized core had 45% recovery. In Hole H005, a face bit was used during pressure coring where 13 cores were collected and 9 cores remained pressurized. Core recovery in Hole H005 was much higher, at about 75%. The type of bit was not the only difference between the holes, however. Drilling mud was used throughout the drilling and pressure coring of Hole H002, while only seawater was used during the first 80m of pressure cores collected in Hole H005. Herein we focus on lithologic analysis of Hole H002 with the goal of documenting and understanding core recovery in Hole H002 to compare with Hole H005. X-ray Computed Tomography (XCT) images were collected by Geotek on pressurized cores, mostly from Hole H005, and at Ohio State on unpressurized cores, mostly from Hole H002. The XCT images of unpressurized cores show minimal sedimentary structures and layering, unlike the XCT images acquired on the pressurized, hydrate-bearing cores. Only small sections of the unpressurized cores remained intact. The unpressurized cores appear to have two prominent facies: 1) silt that did not retain original sedimentary fabric and often was loose within the core barrel, and 2) dense mud sections with some sedimentary structures and layering present. On the XCT images, drilling mud appears to be concentrated on the sides of cores, but also appears in layers and fractures within intact core sections. On microscope images, the drilling mud also appears to saturate the pores in some silt intervals. Further analysis of the unpressurized cores is planned, including X-ray diffraction, grain size analysis and porosity measurements. These results will be compared to the pressurized cores to understand if further lithologic factors could have affected core recovery.

NETL Extreme Drilling Laboratory Studies High Pressure High Temperature Drilling Phenomena

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

Lyons, K.D.; Honeygan, S.; Moroz, T

2007-06-01

The U.S. Department of Energy’s National Energy Technology Laboratory (NETL) established an Extreme Drilling Lab to engineer effective and efficient drilling technologies viable at depths greater than 20,000 feet. This paper details the challenges of ultra-deep drilling, documents reports of decreased drilling rates as a result of increasing fluid pressure and temperature, and describes NETL’s Research and Development activities. NETL is invested in laboratory-scale physical simulation. Their physical simulator will have capability of circulating drilling fluids at 30,000 psi and 480 °F around a single drill cutter. This simulator will not yet be operational by the planned conference dates; therefore,more » the results will be limited to identification of leading hypotheses of drilling phenomena and NETL’s test plans to validate or refute such theories. Of particular interest to the Extreme Drilling Lab’s studies are the combinatorial effects of drilling fluid pressure, drilling fluid properties, rock properties, pore pressure, and drilling parameters, such as cutter rotational speed, weight on bit, and hydraulics associated with drilling fluid introduction to the rock-cutter interface. A detailed discussion of how each variable is controlled in a laboratory setting will be part of the conference paper and presentation.« less

Environmental Measurement-While-Drilling System and Horizontal Directional Drilling Technology Demonstration, Hanford Site

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

Williams, C.V.; Lockwood, G.J.; Normann, R.A.

1999-06-01

The Environmental Measurement-While-Drilling (EMWD) system and Horizontal Directional Drilling (HDD) were successfully demonstrated at the Mock Tank Leak Simulation Site and the Drilling Technology Test Site, Hanford, Washington. The use of directional drilling offers an alternative to vertical drilling site characterization. Directional drilling can develop a borehole under a structure, such as a waste tank, from an angled entry and leveling off to horizontal at the desired depth. The EMWD system represents an innovative blend of new and existing technology that provides the capability of producing real-time environmental and drill bit data during drilling operations. The technology demonstration consisted ofmore » the development of one borehole under a mock waste tank at a depth of {approximately} {minus}8 m ({minus}27 ft.), following a predetermined drill path, tracking the drill path to within a radius of {approximately}1.5 m (5 ft.), and monitoring for zones of radiological activity using the EMWD system. The purpose of the second borehole was to demonstrate the capability of drilling to a depth of {approximately} {minus}21 m ({minus}70 ft.), the depth needed to obtain access under the Hanford waste tanks, and continue drilling horizontally. This report presents information on the HDD and EMWD technologies, demonstration design, results of the demonstrations, and lessons learned.« less

Auto-Gopher: A Wireline Deep Sampler Driven by Piezoelectric Percussive Actuator and EM Rotary Motor

NASA Technical Reports Server (NTRS)

Badescu, Mircea; Ressa, Aaron; Jae Lee, Hyeong; Bar-Cohen, Yoseph; Sherrit, Stewart; Zacny, Kris; Paulsen, Gale L.; Beegle, Luther; Bao, Xiaoqi

2013-01-01

The ability to penetrate subsurfaces and perform sample acquisition at depth of meters may be critical for future NASA in-situ exploration missions to bodies in the solar system, including Mars and Europa. A corer/sampler was developed with the goal of enabling acquisition of samples from depths of several meters where if used on Mars would be beyond the oxidized and sterilized zone. For this purpose, we developed a rotary-hammering coring drill, called Auto-Gopher, which employs a piezoelectric actuated percussive mechanism for breaking formations and an electric motor that rotates the bit to remove the powdered cuttings. This sampler is a wireline mechanism that can be fed into and retrieved from the drilled hole using a winch and a cable. It includes an inchworm anchoring mechanism allowing the drill advancement and weight on bit control without twisting the reeling and power cables. The penetration rate is being optimized by simultaneously activating the percussive and rotary motions of the Auto-Gopher. The percussive mechanism is based on the Ultrasonic/Sonic Drill/Corer (USDC) mechanism that is driven by piezoelectric stack and that was demonstrated to require low axial preload. The design and fabrication of this device were presented in previous publications. This paper presents the results of laboratory and field tests and lessons learned from this development.

System and method for damping vibration in a drill string

DOEpatents

Wassell, Mark Ellsworth [Kingwood, TX; Turner, William Evans [Durham, CT; Burgess, Daniel E [Middletown, CT; Perry, Carl Allison [Middletown, CT

2007-05-22

A system for damping vibration in a drill string can include a valve assembly having a supply of a fluid, a first member, and a second member capable of moving in relation to first member in response to vibration of the drill bit. The first and second members define a first and a second chamber for holding the fluid. Fluid can flow between the first and second chambers in response to the movement of the second member in relation to the first member. The valve assembly can also include a coil or a valve for varying a resistance of the fluid to flow between the first and second chambers.

System and method for damping vibration in a drill string

DOEpatents

Wassell, Mark Ellsworth [Kingwood, TX; Turner, William Evans [Durham, CT; Burgess, Daniel E [Middletown, CT; Perry, Carl Allison [Middletown, CT

2008-05-27

A system for damping vibration in a drill string can include a valve assembly having a supply of a fluid, a first member, and a second member capable of moving in relation to first member in response to vibration of the drill bit. The first and second members define a first and a second chamber for holding the fluid. Fluid can flow between the first and second chambers in response to the movement of the second member in relation to the first member. The valve assembly can also include a coil or a valve for varying a resistance of the fluid to flow between the first and second chambers.

System and method for damping vibration in a drill string

DOEpatents

Wassell, Mark Ellsworth; Turner, William Evans; Burgess, Daniel E.; Perry, Carl Allison

2012-08-14

A system for damping vibration in a drill string can include a valve assembly having a supply of a fluid, a first member, and a second member capable of moving in relation to first member in response to vibration of the drill bit. The first and second members define a first and a second chamber for holding the fluid. Fluid can flow between the first and second chambers in response to the movement of the second member in relation to the first member. The valve assembly can also include a coil or a valve for varying a resistance of the fluid to flow between the first and second chambers.

System and method for damping vibration in a drill string

DOEpatents

Wassell, Mark Ellsworth; Turner, William Evans; Burgess, Daniel E; Perry, Carl Allison

2014-03-04

A system for damping vibration in a drill string can include a valve assembly having a supply of a fluid, a first member, and a second member capable of moving in relation to first member in response to vibration of the drill bit. The first and second members define a first and a second chamber for holding the fluid. Fluid can flow between the first and second chambers in response to the movement of the second member in relation to the first member. The valve assembly can also include a coil or a valve for varying a resistance of the fluid to flow between the first and second chambers.

System and method for damping vibration in a drill string

DOEpatents

Wassell, Mark Ellsworth [Kingwood, TX; Turner, William Evans [Durham, CT; Burgess, Daniel E [Middletown, CT; Perry, Carl Allison [Middletown, CT

2011-08-16

A system for damping vibration in a drill string can include a valve assembly having a supply of a fluid, a first member, and a second member capable of moving in relation to first member in response to vibration of the drill bit. The first and second members define a first and a second chamber for holding the fluid. Fluid can flow between the first and second chambers in response to the movement of the second member in relation to the first member. The valve assembly can also include a coil or a valve for varying a resistance of the fluid to flow between the first and second chambers.

System and method for damping vibration in a drill string

DOEpatents

Wassell, Mark Ellsworth; Turner, William Evans; Burgess, Daniel E; Perry, Carl Allison

2015-02-03

A system for damping vibration in a drill string can include a valve assembly having a supply of a fluid, a first member, and a second member capable of moving in relation to first member in response to vibration of the drill bit. The first and second members define a first and a second chamber for holding the fluid. Fluid can flow between the first and second chambers in response to the movement of the second member in relation to the first member. The valve assembly can also include a coil or a valve for varying a resistance of the fluid to flow between the first and second chambers.

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

Cook, J.M.; Sheppard, M.C.; Houwen, O.H.

Previous work on shale mechanical properties has focused on the slow deformation rates appropriate to wellbore deformation. Deformation of shale under a drill bit occurs at a very high rate, and the failure properties of the rock under these conditions are crucial in determining bit performance and in extracting lithology and pore-pressure information from drilling parameters. Triaxial tests were performed on two nonswelling shales under a wide range of strain rates and confining and pore pressures. At low strain rates, when fluid is relatively free to move within the shale, shale deformation and failure are governed by effective stress ormore » pressure (i.e., total confining pressure minus pore pressure), as is the case for ordinary rock. If the pore pressure in the shale is high, increasing the strain rate beyond about 0.1%/sec causes large increases in the strength and ductility of the shale. Total pressure begins to influence the strength. At high stain rates, the influence of effective pressure decreases, except when it is very low (i.e., when pore pressure is very high); ductility then rises rapidly. This behavior is opposite that expected in ordinary rocks. This paper briefly discusses the reasons for these phenomena and their impact on wellbore and drilling problems.« less

Seismic Prediction While Drilling (SPWD): Seismic exploration ahead of the drill bit using phased array sources

NASA Astrophysics Data System (ADS)

Jaksch, Katrin; Giese, Rüdiger; Kopf, Matthias

2010-05-01

In the case of drilling for deep reservoirs previous exploration is indispensable. In recent years the focus shifted more on geological structures like small layers or hydrothermal fault systems. Beside 2D- or 3D-seismics from the surface and seismic measurements like Vertical Seismic Profile (VSP) or Seismic While Drilling (SWD) within a borehole these methods cannot always resolute this structures. The resolution is worsen the deeper and smaller the sought-after structures are. So, potential horizons like small layers in oil exploration or fault zones usable for geothermal energy production could be failed or not identified while drilling. The application of a device to explore the geology with a high resolution ahead of the drill bit in direction of drilling would be of high importance. Such a device would allow adjusting the drilling path according to the real geology and would minimize the risk of discovery and hence the costs for drilling. Within the project SPWD a device for seismic exploration ahead of the drill bit will be developed. This device should allow the seismic exploration to predict areas about 50 to 100 meters ahead of the drill bit with a resolution of one meter. At the GFZ a first prototype consisting of different units for seismic sources, receivers and data loggers has been designed and manufactured. As seismic sources four standard magnetostrictive actuators and as receivers four 3-component-geophones are used. Every unit, actuator or geophone, can be rotated in steps of 15° around the longitudinal axis of the prototype to test different measurement configurations. The SPWD prototype emits signal frequencies of about 500 up to 5000 Hz which are significant higher than in VSP and SWD. An increased radiation of seismic wave energy in the direction of the borehole axis allows the view in areas to be drilled. Therefore, every actuator must be controlled independently of each other regarding to amplitude and phase of the source signal to maximize the energy of the seismic source in order to reach a sufficient exploration range. The next step for focusing is to use the method of phased array. Dependent of the seismic wave velocities of the surrounding rock, the distance of the actuators to each other and the used frequencies the signal phases for each actuator can be determined. Since one year several measurements with the prototype have been realized under defined conditions at a test site in a mine. The test site consists of a rock block surrounded from three galleries with a dimension of about 100 by 200 meters. For testing the prototype two horizontal boreholes were drilled. They are directed to one of the gallery to get a strong reflector. The quality of the data of the borehole seismics in amplitude and frequency spectra show overall a good signal-to-noise ratio and correlate strongly with the fracture density along the borehole and are associated with a lower signal-to-noise ratio. Additionally, the geophones of the prototype show reflections from ahead and rearward in the seismic data. In particular, the reflections from the gallery ahead are used for the calibration of focusing. The direct seismic wave field indicates distinct compression and shear waves. The analysis of several seismic measurements with a focus on the direct seismic waves shows that the phased array technology explicit can influence the directional characteristics of the radiated seimic waves. The amplitudes of the seismic waves can be enhanced up to three times more in the desired direction and simultaneously be attenuated in the reverse direction. A major step for the directional investigation in boreholes has accomplished. But the focusing of the seismic waves has to be improved to maximize the energy in the desired direction in more measurements by calibrating the initiating seismic signals of the sources. A next step this year is the development of a wireline prototype for application in vertical boreholes with depths not more than 2000 meters are planned. The prototype must be modified and adapted to the conditions in deep boreholes with respect to pressure and temperature. This project is funded by the German Federal Environment Ministry.

77 FR 25749 - Certain Drill Bits and Products Containing Same; Notice of Receipt of Complaint; Solicitation of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-01

...., Peru; Christensen Chile S.A., Chile; Diamantina Christensen Trading Inc., Panama; and Intermountain... document electronically on or before the deadlines stated above and submit 8 true paper copies to the...

Rock melting technology and geothermal drilling

NASA Technical Reports Server (NTRS)

Rowley, J. C.

1974-01-01

National awareness of the potential future shortages in energy resources has heightened interest in exploration and utilization of a variety of geothermal energy (GTE) reservoirs. The status of conventional drilling of GTE wells is reviewed briefly and problem areas which lead to higher drilling costs are identified and R and D directions toward solution are suggested. In the immediate future, an expanded program of drilling in GTE formations can benefit from improvements in drilling equipment and technology normally associated with oil or gas wells. Over a longer time period, the new rock-melting drill bits being developed as a part of the Los Alamos Scientific Laboratory's Subterrene Program offer new solutions to a number of problems which frequently hamper GTE drilling, including the most basic problem - high temperature. Two of the most favorable characteristics of rock-melting penetrators are their ability to operate effectively in hot rock and produce glass linings around the hole as an integral part of the drilling process. The technical advantages to be gained by use of rock-melting penetrators are discussed in relation to the basic needs for GTE wells.

Passive and semi-active heave compensator: Project design methodology and control strategies.

PubMed

Cuellar Sanchez, William Humberto; Linhares, Tássio Melo; Neto, André Benine; Fortaleza, Eugênio Libório Feitosa

2017-01-01

Heave compensator is a system that mitigates transmission of heave movement from vessels to the equipment in the vessel. In drilling industry, a heave compensator enables drilling in offshore environments. Heave compensator attenuates movement transmitted from the vessel to the drill string and drill bit ensuring security and efficiency of the offshore drilling process. Common types of heave compensators are passive, active and semi-active compensators. This article presents 4 main points. First, a bulk modulus analysis obtains a simple condition to determine if the bulk modulus can be neglected in the design of hydropneumatic passive heave compensator. Second, the methodology to design passive heave compensators with the desired frequency response. Third, four control methodologies for semi-active heave compensator are tested and compared numerically. Lastly, we show experimental results obtained from a prototype with the methodology developed to design passive heave compensator.

Passive and semi-active heave compensator: Project design methodology and control strategies

PubMed Central

Cuellar Sanchez, William Humberto; Neto, André Benine; Fortaleza, Eugênio Libório Feitosa

2017-01-01

Heave compensator is a system that mitigates transmission of heave movement from vessels to the equipment in the vessel. In drilling industry, a heave compensator enables drilling in offshore environments. Heave compensator attenuates movement transmitted from the vessel to the drill string and drill bit ensuring security and efficiency of the offshore drilling process. Common types of heave compensators are passive, active and semi-active compensators. This article presents 4 main points. First, a bulk modulus analysis obtains a simple condition to determine if the bulk modulus can be neglected in the design of hydropneumatic passive heave compensator. Second, the methodology to design passive heave compensators with the desired frequency response. Third, four control methodologies for semi-active heave compensator are tested and compared numerically. Lastly, we show experimental results obtained from a prototype with the methodology developed to design passive heave compensator. PMID:28813494

Computer Series, 13: Bits and Pieces, 11.

ERIC Educational Resources Information Center

Moore, John W., Ed.

1982-01-01

Describes computer programs (with ordering information) on various topics including, among others, modeling of thermodynamics and economics of solar energy, radioactive decay simulation, stoichiometry drill/tutorial (in Spanish), computer-generated safety quiz, medical chemistry computer game, medical biochemistry question bank, generation of…

Dynamics of a distributed drill string system: Characteristic parameters and stability maps

NASA Astrophysics Data System (ADS)

Aarsnes, Ulf Jakob F.; van de Wouw, Nathan

2018-03-01

This paper involves the dynamic (stability) analysis of distributed drill-string systems. A minimal set of parameters characterizing the linearized, axial-torsional dynamics of a distributed drill string coupled through the bit-rock interaction is derived. This is found to correspond to five parameters for a simple drill string and eight parameters for a two-sectioned drill-string (e.g., corresponding to the pipe and collar sections of a drilling system). These dynamic characterizations are used to plot the inverse gain margin of the system, parametrized in the non-dimensional parameters, effectively creating a stability map covering the full range of realistic physical parameters. This analysis reveals a complex spectrum of dynamics not evident in stability analysis with lumped models, thus indicating the importance of analysis using distributed models. Moreover, it reveals trends concerning stability properties depending on key system parameters useful in the context of system and control design aiming at the mitigation of vibrations.

Cloning and bioinformatics analysis of PDC genes from Hylocereus undatus

NASA Astrophysics Data System (ADS)

Wu, Yunli; Luo, Xian; Lu, Han; Shen, Yu; Yuan, Lei; Luo, Lan

2018-04-01

The cDNA of PDC1 and PDC2 were amplified from the seedling of Hylocereus undatus `Guangming 2' by the technique of RACE (rapid amplification of cDNA ends). The PDC1 and PDC2 had a length of 1191bp and 2046 bp, and an open reading frame that encoded a protein of 351 and 604 amino acids, respectively. PDC1 was similar to PDC2 in motif and domain, which indicated that the two protein was relatively conserved to some extent. The 3D structure prediction showed that both of the two proteins of PDC1 and PDC2 were homotetramers. Amino acid sequence comparisons suggested that PDC1 had high identity with Chenopodium quinoa PDC1 (88% identity), PDC2 had high identity with Beta vulgaris PDC2 (84% identity).

Drilling electrode for real-time measurement of electrical impedance in bone tissues.

PubMed

Dai, Yu; Xue, Yuan; Zhang, Jianxun

2014-03-01

In order to prevent possible damages to soft tissues, reliable monitoring methods are required to provide valuable information on the condition of the bone being cut. This paper describes the design of an electrical impedance sensing drill developed to estimate the relative position between the drill and the bone being drilled. The two-electrode method is applied to continuously measure the electrical impedance during a drill feeding movement: two copper wire brushes are used to conduct electricity in the rotating drill and then the drill is one electrode; a needle is inserted into the soft tissues adjacent to the bone being drilled and acts as another electrode. Considering that the recorded electrical impedance is correlated with the insertion depth of the drill, we theoretically calculate the electrode-tissue contact impedance and prove that the rate of impedance change varies considerably when the drill bit crosses the boundary between two different bone tissues. Therefore, the rate of impedance change is used to determine whether the tip of the drill is located in one of cortical bone, cancellous bone, and cortical bone near a boundary with soft tissue. In vitro experiments in porcine thoracic spines were performed to demonstrate the feasibility of the impedance sensing drill. The experimental results indicate that the drill, used with the proposed data-processing method, can provide accurate and reliable breakthrough detection in the bone-drilling process.

Impact of Drilling Operations on Lunar Volatiles Capture: Thermal Vacuum Tests

NASA Technical Reports Server (NTRS)

Kleinhenz, Julie E.; Paulsen, Gale; Zacny, Kris; Smith, Jim

2015-01-01

In Situ Resource Utilization (ISRU) enables future planetary exploration by using local resources to supply mission consumables. This idea of 'living off the land' has the potential to reduce mission cost and risk. On the moon, water has been identified as a potential resource (for life support or propellant) at the lunar poles, where it exists as ice in the subsurface. However, the depth and content of this resource has yet to be confirmed on the ground; only remote detection data exists. The upcoming Resource Prospector mission (RP) will 'ground-truth' the water using a rover, drill, and the RESOLVE science package. As the 2020 planned mission date nears, component level hardware is being tested in relevant lunar conditions (thermal vacuum). In August 2014 a series of drilling tests were performed using the Honeybee Robotics Lunar Prospecting Drill inside a 'dirty' thermal vacuum chamber at the NASA Glenn Research Center. The drill used a unique auger design to capture and retain the lunar regolith simulant. The goal of these tests was to investigate volatiles (water) loss during drilling and sample transfer to a sample crucible in order to validate this regolith sampling method. Twelve soil samples were captured over the course of two tests at pressures of 10(exp-5) Torr and ambient temperatures between -80C to -20C. Each sample was obtained from a depth of 40 cm to 50 cm within a cryogenically frozen bed of NU-LHT-3M lunar regolith simulant doped with 5 wt% water. Upon acquisition, each sample was transferred and hermetically sealed inside a crucible. The samples were later baked out to determine water wt% and in turn volatile loss by following ASTM standard practices. Of the twelve tests, four sealed properly and lost an average of 30% of their available water during drilling and transfer. The variability in the results correlated well with ambient temperature (lower the temperature lower volatiles loss) and the trend agreed with the sublimation rates for the same temperature. Moisture retention also correlated with quantity of sample: a larger amount of material resulted in less water loss. The drilling process took an average of 10 minutes to capture and transfer each sample. The drilling power was approximately 20 Watt with a Weight on Bit of approximately 30 N. The bit temperature indicated little heat input into formation during the drilling process.

Real Time Mud Gas Logging During Drilling of DFDP-2B

NASA Astrophysics Data System (ADS)

Mathewson, L. A.; Toy, V.; Menzies, C. D.; Zimmer, M.; Erzinger, J.; Niedermann, S.; Cox, S.

2015-12-01

The Deep Fault Drilling Project (DFDP) aims to improve our understanding of the Alpine Fault Zone, a tectonically active mature fault system in New Zealand known to rupture in large events, by deep scientific drilling. The borehole DFDP-2B approached the Alpine Fault at depth, reaching a final depth of 892 m (820 m true vertical depth). Online gas analysis (OLGA) while drilling tracked changes in the composition of gases extracted from the circulating drill mud. The composition of fluids from fault zones can provide information about their origins, flow rates and -paths, fluid-rock interactions along these paths, and the permeability structure of the faulted rock mass. Apart from an atmospheric input, the gases in drilling mud derive from the pore space of rock, crushed at the drill bit, and from permeable layers intersected by the borehole. The rapid formation of mud wall cake seals the borehole from further fluid inflow, hence formation-derived gases enter mostly at the depth of the drill bit. OLGA analyses N2, O2, Ar, CO2, CH4, He, and H2 on a mass spectrometer, hydrocarbons CH4, C2H6, C3H8, i-C4H10, and n-C4H10 on a gas chromatograph, and Rn using a lucas-cell detector. Gas was sampled for offline analyses on noble gas and stable isotopes to complement the OLGA dataset. The principle formation-derived gases found in drilling mud during drilling of DFDP-2 were CO2 and CH4, with smaller component of H2 and He2. High radon activity is interpreted to reflect intervals of active fluid flow through highly fractured and faulted rock. 3He/4He values in many samples were extremely air-contaminated, i.e. there was almost no excess of non-atmospheric He. The 3He/4He values measured at 236 m and 610 m, which are the only analyses with uncertainties <100%, are very similar to those measured in hot springs along the Alpine Fault, e.g. Fox River (0.64 Ra), Copland (0.42 Ra), Lower Wanganui (0.81 Ra). We will compare these data to those gathered using OLGA and discuss the implications.

A predictive bone drilling force model for haptic rendering with experimental validation using fresh cadaveric bone.

PubMed

Lin, Yanping; Chen, Huajiang; Yu, Dedong; Zhang, Ying; Yuan, Wen

2017-01-01

Bone drilling simulators with virtual and haptic feedback provide a safe, cost-effective and repeatable alternative to traditional surgical training methods. To develop such a simulator, accurate haptic rendering based on a force model is required to feedback bone drilling forces based on user input. Current predictive bone drilling force models based on bovine bones with various drilling conditions and parameters are not representative of the bone drilling process in bone surgery. The objective of this study was to provide a bone drilling force model for haptic rendering based on calibration and validation experiments in fresh cadaveric bones with different bone densities. Using a commonly used drill bit geometry (2 mm diameter), feed rates (20-60 mm/min) and spindle speeds (4000-6000 rpm) in orthognathic surgeries, the bone drilling forces of specimens from two groups were measured and the calibration coefficients of the specific normal and frictional pressures were determined. The comparison of the predicted forces and the measured forces from validation experiments with a large range of feed rates and spindle speeds demonstrates that the proposed bone drilling forces can predict the trends and average forces well. The presented bone drilling force model can be used for haptic rendering in surgical simulators.

Temporal bone borehole accuracy for cochlear implantation influenced by drilling strategy: an in vitro study.

PubMed

Kobler, Jan-Philipp; Schoppe, Michael; Lexow, G Jakob; Rau, Thomas S; Majdani, Omid; Kahrs, Lüder A; Ortmaier, Tobias

2014-11-01

Minimally invasive cochlear implantation is a surgical technique which requires drilling a canal from the mastoid surface toward the basal turn of the cochlea. The choice of an appropriate drilling strategy is hypothesized to have significant influence on the achievable targeting accuracy. Therefore, a method is presented to analyze the contribution of the drilling process and drilling tool to the targeting error isolated from other error sources. The experimental setup to evaluate the borehole accuracy comprises a drill handpiece attached to a linear slide as well as a highly accurate coordinate measuring machine (CMM). Based on the specific requirements of the minimally invasive cochlear access, three drilling strategies, mainly characterized by different drill tools, are derived. The strategies are evaluated by drilling into synthetic temporal bone substitutes containing air-filled cavities to simulate mastoid cells. Deviations from the desired drill trajectories are determined based on measurements using the CMM. Using the experimental setup, a total of 144 holes were drilled for accuracy evaluation. Errors resulting from the drilling process depend on the specific geometry of the tool as well as the angle at which the drill contacts the bone surface. Furthermore, there is a risk of the drill bit deflecting due to synthetic mastoid cells. A single-flute gun drill combined with a pilot drill of the same diameter provided the best results for simulated minimally invasive cochlear implantation, based on an experimental method that may be used for testing further drilling process improvements.

Logging-while-coring method and apparatus

DOEpatents

Goldberg, David S.; Myers, Gregory J.

2007-11-13

A method and apparatus for downhole coring while receiving logging-while-drilling tool data. The apparatus includes core collar and a retrievable core barrel. The retrievable core barrel receives core from a borehole which is sent to the surface for analysis via wireline and latching tool The core collar includes logging-while-drilling tools for the simultaneous measurement of formation properties during the core excavation process. Examples of logging-while-drilling tools include nuclear sensors, resistivity sensors, gamma ray sensors, and bit resistivity sensors. The disclosed method allows for precise core-log depth calibration and core orientation within a single borehole, and without at pipe trip, providing both time saving and unique scientific advantages.

Logging-while-coring method and apparatus

DOEpatents

Goldberg, David S.; Myers, Gregory J.

2007-01-30

A method and apparatus for downhole coring while receiving logging-while-drilling tool data. The apparatus includes core collar and a retrievable core barrel. The retrievable core barrel receives core from a borehole which is sent to the surface for analysis via wireline and latching tool The core collar includes logging-while-drilling tools for the simultaneous measurement of formation properties during the core excavation process. Examples of logging-while-drilling tools include nuclear sensors, resistivity sensors, gamma ray sensors, and bit resistivity sensors. The disclosed method allows for precise core-log depth calibration and core orientation within a single borehole, and without at pipe trip, providing both time saving and unique scientific advantages.

Derivation and experimental validation of an analytical criterion for the identification of self-excited modes in drilling systems

NASA Astrophysics Data System (ADS)

Hohl, Andreas; Tergeist, Mathias; Oueslati, Hatem; Jain, Jayesh R.; Herbig, Christian; Ostermeyer, Georg-Peter; Reckmann, Hanno

2015-04-01

Drilling system applications are subject to torsional vibrations that are induced by self-excitation mechanisms. A common mechanism is a falling characteristic of contact or cutting forces with respect to the relative velocity between the bit and the formation. To mitigate the effects of this mechanism, it is important to identify modes that are the most likely to be excited. However, in complex structures the identification of critical mode shapes is no trivial task. This paper discusses a criterion derived to identify critical torsional modes in drilling systems that are prone to self-excitation. Basic assumptions are a falling (velocity-weakening) characteristic of the contact forces and only one contributing mode. Multiple contact forces along the structure can be considered with different contact characteristics. Contributing parameters are angular eigenfrequency, deflection of the mode shape at the contact points, modal damping of the examined mode, and the slope of the characteristic of the contact forces at the operating point. In a case study of a drilling system the derived criterion is tested. The case study focuses on torsional vibrations excited by cutting forces observed in field measurements with high amplitudes and accelerations. The corresponding modes are localized to the so-called bottomhole assembly (BHA) at the end of the drilling system. Numerical results from a finite element analysis are compared to downhole measurements to verify the critical modes that are identified with the criterion. In addition, mass and stiffness changes along the structure are intentionally induced to beneficially influence mode shapes. Results indicate that reducing the mode shape at the source of vibration (bit) decreases the excitability of this mode shape.

Active Struts With Variable Spring Stiffness and Damping

NASA Technical Reports Server (NTRS)

Farley, Gary L.

2006-01-01

An ultrasonic rock-abrasion tool (URAT) was developed using the same principle of ultrasonic/sonic actuation as that of the tools described in two prior NASA Tech Briefs articles: Ultrasonic/ Sonic Drill/Corers With Integrated Sensors (NPO-20856), Vol. 25, No. 1 (January 2001), page 38 and Ultrasonic/ Sonic Mechanisms for Drilling and Coring (NPO-30291), Vol. 27, No. 9 (September 2003), page 65. Hence, like those tools, the URAT offers the same advantages of low power demand, mechanical simplicity, compactness, and ability to function with very small axial loading (very small contact force between tool and rock). Like a tool described in the second of the cited previous articles, a URAT includes (1) a drive mechanism that comprises a piezoelectric ultrasonic actuator, an amplification horn, and a mass that is free to move axially over a limited range and (2) an abrasion tool bit. A URAT tool bit is a disk that has been machined or otherwise formed to have a large number of teeth and an overall shape chosen to impart the desired shape (which could be flat or curved) to the rock surface to be abraded. In operation, the disk and thus the teeth are vibrated in contact with the rock surface. The concentrated stresses at the tips of the impinging teeth repeatedly induce microfractures and thereby abrade the rock. The motion of the tool induces an ultrasonic transport effect that displaces the cuttings from the abraded area. The figure shows a prototype URAT. A piezoelectric-stack/horn actuator is housed in a cylindrical container. The movement of the actuator and bit with respect to the housing is aided by use of mechanical sliders. A set of springs accommodates the motion of the actuator and bit into or out of the housing through an axial range between 5 and 7 mm. The springs impose an approximately constant force of contact between the tool bit and the rock to be abraded. A dust shield surrounds the bit, serving as a barrier to reduce the migration of rock debris to sensitive instrumentation or mechanisms in the vicinity. A bushing at the tool-bit end of the housing reduces the flow of dust into the actuator and retains the bit when no axial load is applied.

Ultrasonically Actuated Tools for Abrading Rock Surfaces

NASA Technical Reports Server (NTRS)

Dolgin, Benjamin; Sherrit, Stewart; Bar-Cohen, Yoseph; Rainen, Richard; Askin, Steve; Bickler, Donald; Lewis, Donald; Carson, John; Dawson, Stephen; Bao, Xiaoqi;

Soil properties affecting wheat yields following drilling-fluid application.

PubMed

Bauder, T A; Barbarick, K A; Ippolito, J A; Shanahan, J F; Ayers, P D

2005-01-01

Oil and gas drilling operations use drilling fluids (mud) to lubricate the drill bit and stem, transport formation cuttings to the surface, and seal off porous geologic formations. Following completion of the well, waste drilling fluid is often applied to cropland. We studied potential changes in soil compaction as indicated by cone penetration resistance, pH, electrical conductivity (EC(e)), sodium adsorption ratio (SAR), extractable soil and total straw and grain trace metal and nutrient concentrations, and winter wheat (Triticum aestivum L. 'TAM 107') grain yield following water-based, bentonitic drilling-fluid application (0-94 Mg ha(-1)) to field test plots. Three methods of application (normal, splash-plate, and spreader-bar) were used to study compaction effects. We measured increasing SAR, EC(e), and pH with drilling-fluid rates, but not to levels detrimental to crop production. Field measurements revealed significantly higher compaction within areas affected by truck travel, but also not enough to affect crop yield. In three of four site years, neither drilling-fluid rate nor application method affected grain yield. Extractions representing plant availability and plant analyses results indicated that drilling fluid did not significantly increase most trace elements or nutrient concentrations. These results support land application of water-based bentonitic drilling fluids as an acceptable practice on well-drained soils using controlled rates.

Advanced Seismic While Drilling System

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

Robert Radtke; John Fontenot; David Glowka

A breakthrough has been discovered for controlling seismic sources to generate selectable low frequencies. Conventional seismic sources, including sparkers, rotary mechanical, hydraulic, air guns, and explosives, by their very nature produce high-frequencies. This is counter to the need for long signal transmission through rock. The patent pending SeismicPULSER{trademark} methodology has been developed for controlling otherwise high-frequency seismic sources to generate selectable low-frequency peak spectra applicable to many seismic applications. Specifically, we have demonstrated the application of a low-frequency sparker source which can be incorporated into a drill bit for Drill Bit Seismic While Drilling (SWD). To create the methodology ofmore » a controllable low-frequency sparker seismic source, it was necessary to learn how to maximize sparker efficiencies to couple to, and transmit through, rock with the study of sparker designs and mechanisms for (a) coupling the sparker-generated gas bubble expansion and contraction to the rock, (b) the effects of fluid properties and dynamics, (c) linear and non-linear acoustics, and (d) imparted force directionality. After extensive seismic modeling, the design of high-efficiency sparkers, laboratory high frequency sparker testing, and field tests were performed at the University of Texas Devine seismic test site. The conclusion of the field test was that extremely high power levels would be required to have the range required for deep, 15,000+ ft, high-temperature, high-pressure (HTHP) wells. Thereafter, more modeling and laboratory testing led to the discovery of a method to control a sparker that could generate low frequencies required for deep wells. The low frequency sparker was successfully tested at the Department of Energy Rocky Mountain Oilfield Test Center (DOE RMOTC) field test site in Casper, Wyoming. An 8-in diameter by 26-ft long SeismicPULSER{trademark} drill string tool was designed and manufactured by TII. An APS Turbine Alternator powered the SeismicPULSER{trademark} to produce two Hz frequency peak signals repeated every 20 seconds. Since the ION Geophysical, Inc. (ION) seismic survey surface recording system was designed to detect a minimum downhole signal of three Hz, successful performance was confirmed with a 5.3 Hz recording with the pumps running. The two Hz signal generated by the sparker was modulated with the 3.3 Hz signal produced by the mud pumps to create an intense 5.3 Hz peak frequency signal. The low frequency sparker source is ultimately capable of generating selectable peak frequencies of 1 to 40 Hz with high-frequency spectra content to 10 kHz. The lower frequencies and, perhaps, low-frequency sweeps, are needed to achieve sufficient range and resolution for realtime imaging in deep (15,000 ft+), high-temperature (150 C) wells for (a) geosteering, (b) accurate seismic hole depth, (c) accurate pore pressure determinations ahead of the bit, (d) near wellbore diagnostics with a downhole receiver and wired drill pipe, and (e) reservoir model verification. Furthermore, the pressure of the sparker bubble will disintegrate rock resulting in an increased overall rates of penetration. Other applications for the SeismicPULSER{trademark} technology are to deploy a low-frequency source for greater range on a wireline for Reverse Vertical Seismic Profiling (RVSP) and Cross-Well Tomography. Commercialization of the technology is being undertaken by first contacting stakeholders to define the value proposition for rig site services utilizing SeismicPULSER{trademark} technologies. Stakeholders include national oil companies, independent oil companies, independents, service companies, and commercial investors. Service companies will introduce a new Drill Bit SWD service for deep HTHP wells. Collaboration will be encouraged between stakeholders in the form of joint industry projects to develop prototype tools and initial field trials. No barriers have been identified for developing, utilizing, and exploiting the low-frequency SeismicPULSER{trademark} source in a variety of applications. Risks will be minimized since Drill Bit SWD will not interfere with the drilling operation, and can be performed in a relatively quiet environment when the pumps are turned off. The new source must be integrated with other Measurement While Drilling (MWD) tools. To date, each of the oil companies and service companies contacted have shown interest in participating in the commercialization of the low-frequency SeismicPULSER{trademark} source. A technical paper has been accepted for presentation at the 2009 Offshore Technology Conference (OTC) in a Society of Exploration Geologists/American Association of Petroleum Geophysicists (SEG/AAPG) technical session.« less

High-pressure high-temperature rheological studies of colloidal suspensions with carbon nanotube

NASA Astrophysics Data System (ADS)

Baby, Anoop; Sadr, Reza; Yarc, Rommel; Amani, Mahmood

2017-11-01

Selection of the drilling fluid, drilling mud, is vital in minimizing the cost and time required for the drilling in oil fields. Drilling mud aids in cooling, lubricating drilling bit, removing the debries from the drill bore and maintaining the wellbore stability. Owing to the enhanced thermo-physical properties and stable nature, suspensions of nanoparticles have been suggested for drilling fluids. High-pressure and high-temperature rheology of a nanomud suspension (nano particles suspended in a mud solution) is studied here. The nanomud is prepared by dispersing a water-based drilling mud suspension (water with 1% Bentonite and 7% Barite particles) with multi-walled carbon nanotubes, MWCNT. The effect of pressure, temperature, and shear rate are independently studied for the various particle loading of the nanoparticles. Viscosity values are measured at a maximum pressure of 170MPa with temperatures ranging from ambient to 180oC. The effect of MWCNT concentration and variation in shear rate are also investigated A shear thinning non-Newtonian behavior is observed for the basemud and the nanomud samples for all cases. The basemud showed an increase in viscosity with an increase in pressure. However, with MWCNT particle addition, this trend is observed to have reversed.

9 CFR 590.136 - Facilities and equipment to be furnished by official plants for use of inspectors in performing...

Code of Federal Regulations, 2012 CFR

2012-01-01

... product, and acceptable candling light, flashlight, heavy duty, high speed drill with an eleven sixteenths-inch or larger bit of sufficient length to reach the bottom of containers used for frozen eggs, metal...

9 CFR 590.136 - Facilities and equipment to be furnished by official plants for use of inspectors in performing...

Code of Federal Regulations, 2013 CFR

2013-01-01

... product, and acceptable candling light, flashlight, heavy duty, high speed drill with an eleven sixteenths-inch or larger bit of sufficient length to reach the bottom of containers used for frozen eggs, metal...

9 CFR 590.136 - Facilities and equipment to be furnished by official plants for use of inspectors in performing...

Code of Federal Regulations, 2010 CFR

2010-01-01

... product, and acceptable candling light, flashlight, heavy duty, high speed drill with an eleven sixteenths-inch or larger bit of sufficient length to reach the bottom of containers used for frozen eggs, metal...

9 CFR 590.136 - Facilities and equipment to be furnished by official plants for use of inspectors in performing...

Code of Federal Regulations, 2014 CFR

2014-01-01

... product, and acceptable candling light, flashlight, heavy duty, high speed drill with an eleven sixteenths-inch or larger bit of sufficient length to reach the bottom of containers used for frozen eggs, metal...

9 CFR 590.136 - Facilities and equipment to be furnished by official plants for use of inspectors in performing...

Code of Federal Regulations, 2011 CFR

2011-01-01

... product, and acceptable candling light, flashlight, heavy duty, high speed drill with an eleven sixteenths-inch or larger bit of sufficient length to reach the bottom of containers used for frozen eggs, metal...

Inlet Cover On the Curiosity Rover

NASA Image and Video Library

2018-06-04

The drill bit of NASA's Curiosity Mars rover over one of the sample inlets on the rover's deck. The inlets lead to Curiosity's onboard laboratories. This image was taken on Sol 2068 by the rover's Mast Camera (Mastcam). https://photojournal.jpl.nasa.gov/catalog/PIA22327

Use of an Ultrasonic/Sonic Driller/Corer to Obtain Sample Powder for CHEMIN, a Combined XRD/XRF Instrument

NASA Technical Reports Server (NTRS)

Chipera, S. J.; Bish, D. L.; Vaniman, D. T.; Sherrit, S.; Bar-Cohen, Y.; Sarrazin, P.; Blake, D. F.

2003-01-01

A miniature CHEMIN XRD/XRF (X-Ray Diffraction/X-Ray Fluourescence) instrument is currently being developed for definitive mineralogic analysis of soils and rocks on Mars. One of the technical issues that must be addressed in order to enable XRD analysis on an extraterrestrial body is how best to obtain a representative sample powder for analysis. For XRD powder diffraction analyses, it is beneficial to have a fine-grained sample to reduce preferred orientation effects and to provide a statistically significant number of crystallites to the X-ray beam. Although a 2-dimensional detector as used in the CHEMIN instrument will produce good results with poorly prepared powders, the quality of the data will improve if the sample is fine-grained and randomly oriented. An Ultrasonic/Sonic Driller/Corer (USDC) currently being developed at JPL is an effective mechanism of sampling rock to produce cores and powdered cuttings. It requires low axial load (< 5N) and thus offers significant advantages for operation from lightweight platforms and in low gravity environments. The USDC is lightweight (<0.5kg), and can be driven at low power (<5W) using duty cycling. It consists of an actuator with a piezoelectric stack, ultrasonic horn, free-mass, and drill bit. The stack is driven with a 20 kHz AC voltage at resonance. The strain generated by the piezoelectric is amplified by the horn by a factor of up to 10 times the displacement amplitude. The tip impacts the free-mass and drives it into the drill bit in a hammering action. The free-mass rebounds to interact with the horn tip leading to a cyclic rebound at frequencies in the range of 60-1000 Hz. It does not require lubricants, drilling fluid or bit sharpening and it has the potential to operate at high and low temperatures using a suitable choice of piezoelectric material. To assess whether the powder from an ultrasonic drill would be adequate for analyses by an XRD/XRF spectrometer such as CHEMIN, powders obtained from the JPL ultrasonic drill were analyzed and the results were compared to carefully prepared powders obtained using a laboratory bench scale Retsch mill.

Experimental and numerical study of drill bit drop tests on Kuru granite

PubMed Central

Kane, Alexandre; Hokka, Mikko

2017-01-01

This paper presents an experimental and numerical study of Kuru grey granite impacted with a seven-buttons drill bit mounted on an instrumented drop test machine. The force versus displacement curves during the impact, so-called bit–rock interaction (BRI) curves, were obtained using strain gauge measurements for two levels of impact energy. Moreover, the volume of removed rock after each drop test was evaluated by stereo-lithography (three-dimensional surface reconstruction). A modified version of the Holmquist–Johnson–Cook (MHJC) material model was calibrated using Kuru granite test results available from the literature. Numerical simulations of the single drop tests were carried out using the MHJC model available in the LS-DYNA explicit finite-element solver. The influence of the impact energy and additional confining pressure on the BRI curves and the volume of the removed rock is discussed. In addition, the influence of the rock surface shape before impact was evaluated using two different mesh geometries: a flat surface and a hyperbolic surface. The experimental and numerical results are compared and discussed in terms of drilling efficiency through the mechanical specific energy. This article is part of the themed issue ‘Experimental testing and modelling of brittle materials at high strain rates’. PMID:27956511

Reaction of Rhyolitic Magma to its Interception by the IDDP-1 Well, Krafla, 2009

NASA Astrophysics Data System (ADS)

Saubin, É.; Kennedy, B.; Tuffen, H.; Villeneuve, M.; Watson, T.; Nichols, A. R.; Schipper, I.; Cole, J. W.; Mortensen, A. K.; Zierenberg, R. A.

2017-12-01

The unexpected encounter of rhyolitic magma during IDDP-1 geothermal borehole drilling at Krafla, Iceland in 2009, temporarily created the world's hottest geothermal well. This allowed new questions to be addressed. i) How does magma react to drilling? ii) Are the margins of a magma chamber suitable for long-term extraction of supercritical fluids? To investigate these questions, we aim to reconstruct the degassing and deformation behaviour of the enigmatic magma by looking for correlations between textures in rhyolitic material retrieved from the borehole and the recorded drilling data. During drilling, difficulties were encountered in two zones, at 2070 m and below 2093 m depth. Drilling parameters are consistent with the drill bit encountering a high permeability zone and the contact zone of a magma chamber, respectively. Magma was intercepted three times between 2101-2104.4 m depth, which culminated in an increase in standpipe pressure followed by a decrease in weight on bit interpreted as representing the ascent of magma within the borehole. Circulation returned one hour after the last interception, carrying cuttings of glassy particles, felsite with granophyre and contaminant clasts from drilling, which were sampled as a time-series for the following 9 hours. The nature of glassy particles in this time-series varied through time, with a decrease in the proportion of vesicular clasts and a commensurate increase in dense glassy clasts, transitioning from initially colourless to brown glass. Componentry data show a sporadic decrease in felsite (from 34 wt. %), an increase in glassy particles during the first two hours (from 63 wt. % to 94 wt. %) and an increase in contaminant clasts towards the end of the cutting retrieval period. These temporal variations are probably related to the magma body architecture and interactions with the borehole. Transition from vesicular to dense clasts suggests a change in the degassing process that could be related to an early degassing phase caused by drilling-induced decompressions followed by a fast ascent after the last magma interception. Additional data in terms of shape of clasts, vesicularity, density and water content within glassy particles will link textural data to drilling history in order to investigate degassing history, origin of clasts and quenching pressure.

Design and performance study of an orthopaedic surgery robotized module for automatic bone drilling.

PubMed

Boiadjiev, George; Kastelov, Rumen; Boiadjiev, Tony; Kotev, Vladimir; Delchev, Kamen; Zagurski, Kazimir; Vitkov, Vladimir

2013-12-01

Many orthopaedic operations involve drilling and tapping before the insertion of screws into a bone. This drilling is usually performed manually, thus introducing many problems. These include attaining a specific drilling accuracy, preventing blood vessels from breaking, and minimizing drill oscillations that would widen the hole. Bone overheating is the most important problem. To avoid such problems and reduce the subjective factor, automated drilling is recommended. Because numerous parameters influence the drilling process, this study examined some experimental methods. These concerned the experimental identification of technical drilling parameters, including the bone resistance force and temperature in the drilling process. During the drilling process, the following parameters were monitored: time, linear velocity, angular velocity, resistance force, penetration depth, and temperature. Specific drilling effects were revealed during the experiments. The accuracy was improved at the starting point of the drilling, and the error for the entire process was less than 0.2 mm. The temperature deviations were kept within tolerable limits. The results of various experiments with different drilling velocities, drill bit diameters, and penetration depths are presented in tables, as well as the curves of the resistance force and temperature with respect to time. Real-time digital indications of the progress of the drilling process are shown. Automatic bone drilling could entirely solve the problems that usually arise during manual drilling. An experimental setup was designed to identify bone drilling parameters such as the resistance force arising from variable bone density, appropriate mechanical drilling torque, linear speed of the drill, and electromechanical characteristics of the motors, drives, and corresponding controllers. Automatic drilling guarantees greater safety for the patient. Moreover, the robot presented is user-friendly because it is simple to set robot tasks, and process data are collected in real time. Copyright © 2013 John Wiley & Sons, Ltd.

Computer Series, 60: Bits and Pieces, 23.

ERIC Educational Resources Information Center

Moore, John W., Ed.

1985-01-01

Describes: (1) an interactive computer simulation for a science fair display of chromatography inks; (2) analytical chemistry programs; (3) microcomputer-assisted drills in organic synthesis; (4) programs for conformation analysis of ethane and butane; (5) MOLPIX--a program for generating and displaying molecular structures; and (6) chemical…

Delamination measurement of a laminates composite panel due to hole punching based on the focus variation technique

NASA Astrophysics Data System (ADS)

Abdullah, A. B.; Zain, M. S. M.; Abdullah, M. S.; Samad, Z.

2017-07-01

Structural materials, such as composite panels, must be assembled, and such panels are typically constructed via the insertion of a fastener through a drilled hole. The main problem encountered in drilling is delamination, which affects assembly strength. The cost of drilling is also high because of the severe wear on drill bits. The main goal of this research is to develop a new punching method as an alternative to drilling during hole preparation. In this study, the main objective is to investigate the effect of different puncher profiles on the quality of holes punched into carbon fiber reinforcement polymer (CFRP) composite panels. Six types of puncher profiles were fabricated with minimum die clearance (1%), and two quality aspects, namely, incomplete shearing and delamination factor, were measured. The conical puncher incurred the least defects in terms of delamination and yielded an acceptable amount of incomplete shearing in comparison with the other punchers.

Comet sample acquisition for ROSETTA lander mission

NASA Astrophysics Data System (ADS)

Marchesi, M.; Campaci, R.; Magnani, P.; Mugnuolo, R.; Nista, A.; Olivier, A.; Re, E.

2001-09-01

ROSETTA/Lander is being developed with a combined effort of European countries, coordinated by German institutes. The commitment for such a challenging probe will provide a unique opportunity for in-situ analysis of a comet nucleus. The payload for coring, sampling and investigations of comet materials is called SD2 (Sampling Drilling and Distribution). The paper presents the drill/sampler tool and the sample transfer trough modeling, design and testing phases. Expected drilling parameters are then compared with experimental data; limited torque consumption and axial thrust on the tool constraint the operation and determine the success of tests. Qualification campaign involved the structural part and related vibration test, the auger/bit parts and drilling test, and the coring mechanism with related sampling test. Mechanical check of specimen volume is also reported, with emphasis on the measurement procedure and on the mechanical unit. The drill tool and all parts of the transfer chain were tested in the hypothetical comet environment, charcterized by frozen material at extreme low temperature and high vacuum (-160°C, 10-3 Pa).

Extended causal modeling to assess Partial Directed Coherence in multiple time series with significant instantaneous interactions.

PubMed

Faes, Luca; Nollo, Giandomenico

2010-11-01

The Partial Directed Coherence (PDC) and its generalized formulation (gPDC) are popular tools for investigating, in the frequency domain, the concept of Granger causality among multivariate (MV) time series. PDC and gPDC are formalized in terms of the coefficients of an MV autoregressive (MVAR) model which describes only the lagged effects among the time series and forsakes instantaneous effects. However, instantaneous effects are known to affect linear parametric modeling, and are likely to occur in experimental time series. In this study, we investigate the impact on the assessment of frequency domain causality of excluding instantaneous effects from the model underlying PDC evaluation. Moreover, we propose the utilization of an extended MVAR model including both instantaneous and lagged effects. This model is used to assess PDC either in accordance with the definition of Granger causality when considering only lagged effects (iPDC), or with an extended form of causality, when we consider both instantaneous and lagged effects (ePDC). The approach is first evaluated on three theoretical examples of MVAR processes, which show that the presence of instantaneous correlations may produce misleading profiles of PDC and gPDC, while ePDC and iPDC derived from the extended model provide here a correct interpretation of extended and lagged causality. It is then applied to representative examples of cardiorespiratory and EEG MV time series. They suggest that ePDC and iPDC are better interpretable than PDC and gPDC in terms of the known cardiovascular and neural physiologies.

Chitosan-bound pyridinedicarboxylate Ni(II) and Fe(III) complex biopolymer films as waste water decyanidation agents.

PubMed

Adewuyi, Sheriff; Jacob, Julianah Modupe; Olaleye, Oluwatoyin Omolola; Abdulraheem, Taofiq Olanrewaju; Tayo, Jubril Ayopo; Oladoyinbo, Fatai Oladipupo

2016-10-20

Chitosan is a biopolymer with immense structural advantage for chemical and mechanical modifications to generate novel properties, functions and applications. This work depicts new pyridinedicarboxylicacid (PDC) crosslinked chitosan-metal ion films as veritable material for cyanide ion removal from aqueous solution. The PDC-crosslinked chitosan-metal films (PDC-Chit-Ni(II) and PDC-Chit-Fe(III)) were formed by complexing PDC-crosslinked chitosan film with anhydrous nickel(II) and iron(III) chloride salts respectively. The PDC-Chit and its metal films were characterized employing various analytical and spectroscopic techniques. The FT-IR, UV-vis and the XRD results confirm the presence of the metal ions in the metal coordinated PDC-crosslinked chitosan film. The surface morphological difference of PDC-Chit-Ni(II) film before and after decyanidation was explored with scanning electron microscopy. Furthermore, the quantitative amount of nickel(II) and iron(III) present in the complex were determined using Atomic Absorption Spectrophotometer as 32.3 and 37.2μg/g respectively which portends the biopolymer film as a good complexing agent. Removal of cyanide from aqueous solution with PDC-Chit, PDC-Chit-Ni(II) and PDC-Chit-Fe(III) films was studied with batch equilibrium experiments. At equilibrium, decyanidation capacity (DC) followed the order PDC-Chit-Ni (II)≈PDC-Chit-Fe(III)>PDC-Chit. PDC-Chit-Ni(II) film gave 100% CN(-) removal within 40min decyanidation owing to favorable coordination geometry. Copyright © 2016 Elsevier Ltd. All rights reserved.

Voice Coil Percussive Mechanism Concept for Hammer Drill

NASA Technical Reports Server (NTRS)

Okon, Avi

2009-01-01

A hammer drill design of a voice coil linear actuator, spring, linear bearings, and a hammer head was proposed. The voice coil actuator moves the hammer head to produce impact to the end of the drill bit. The spring is used to store energy on the retraction and to capture the rebound energy after each impact for use in the next impact. The maximum actuator stroke is 20 mm with the hammer mass being 200 grams. This unit can create impact energy of 0.4 J with 0.8 J being the maximum. This mechanism is less complex than previous devices meant for the same task, so it has less mass and less volume. Its impact rate and energy are easily tunable without changing major hardware components. The drill can be driven by two half-bridges. Heat is removed from the voice coil via CO2 conduction.

Low-level HIV infection of plasmacytoid dendritic cells: onset of cytopathic effects and cell death after PDC maturation.

PubMed

Schmidt, Barbara; Scott, Iain; Whitmore, Robert G; Foster, Hillary; Fujimura, Sue; Schmitz, Juergen; Levy, Jay A

2004-11-24

Plasmacytoid dendritic cells (PDC), the natural type-1 interferon (IFN) producing cells, are part of the innate immune defense against human immunodeficiency virus (HIV). PDC numbers are reduced in advanced stages of infection. These cells can be infected in vivo by HIV since highly purified PDC showed evidence of infectious HIV. Moreover, when PDC derived from uninfected donors were exposed to high-titered HIV isolates, productive infection occurred although with low-level replication. Using real-time amplification, PDC and unstimulated CD4+ cells were found equally susceptible to HIV infection; however, HIV replication was considerably limited in the PDC. Virus replication was enhanced after PDC treatment with CD40L and antibodies against IFN-alpha, most likely reflecting the reduction in IFN-alpha activity. On maturation, the infected PDC showed multinuclear cell syncytia formation and death. These findings indicate that PDC can be reservoirs for HIV dissemination and that HIV infection of PDC can contribute to their decline.

Plastic Drill Bits

ERIC Educational Resources Information Center

Roman, Harry T.

2013-01-01

This article encourages students to think multidimensionally and in a multidisciplinary fashion with this challenge, and choose a team that can support this kind of thinking. Presented is a challenge in which a major home improvement company makes tools and accessories for use by experienced and new homeowners. This company would like to provide…

Computer Series, 65. Bits and Pieces, 26.

ERIC Educational Resources Information Center

Moore, John W., Ed.

1985-01-01

Describes: (l) a microcomputer-based system for filing test questions and assembling examinations; (2) microcomputer use in practical and simulated experiments of gamma rays scattering by outer shell electrons; (3) an interactive, screen-oriented, general linear regression program; and (4) graphics drill and game programs for benzene synthesis.…

Horizontal technology helps spark Louisiana`s Austin chalk trend

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

Koen, A.D.

1996-04-29

A handful of companies paced by some of the most active operators in the US are pressing the limits of horizontal technology to ramp up Cretaceous Austin chalk exploration and development (E and D) across Louisiana. Companies find applications in Louisiana for lessons learned drilling horizontal wells to produce chalk intervals in Texas in Giddings, Pearsall, and Brookeland fields. Continuing advances in horizontal well technology are helping operators deal with deeper, hotter reservoirs in more complex geological settings that typify the chalk in Louisiana. Better horizontal drilling, completion, formation evaluation, and stimulation techniques have enabled operators to produce oil andmore » gas from formations previously thought to be uneconomical. Most of the improved capabilities stem from better horizontal tools. Horizontal drilling breakthroughs include dual powered mud motors and retrievable whipstocks, key links in the ability to drill wells with more than one horizontal lateral. Better geosteering tools have enabled operators to maintain horizontal wellbores in desired intervals by signaling bit positions downhole while drilling. This paper reviews the technology and provides a historical perspective on the various drilling programs which have been completed in this trend. It also makes predictions on future drilling successes.« less

Residual stress measurement of PMMA by combining drilling-hole with digital speckle correlation method

NASA Astrophysics Data System (ADS)

Yao, X. F.; Xiong, T. C.; Xu, H. M.; Wan, J. P.; Long, G. R.

2008-11-01

The residual stresses of the PMMA (polymethyl methacrylate) specimens after being drilled, reamed and polished respectively are investigated using the digital speckle correlation experimental method,. According to the displacement fields around the correlated calculated region, the polynomial curve fitting method is used to obtain the continuous displacement fields, and the strain fields can be obtained from the derivative of the displacement fields. Considering the constitutive equation of the material, the expression of the residual stress can be presented. During the data processing, according to the fitting effect of the data, the calculation region of the correlated speckles and the degree of the polynomial fitting curve is decided. These results show that the maximum stress is at the hole-wall of the drilling hole specimen and with the increasing of the diameter of the drilled hole, the residual stress resulting from the hole drilling increases, whereas the process of reaming and polishing hole can reduce the residual stress. The relative large discrete degree of the residual stress is due to the chip removal ability of the drill bit, the cutting feed of the drill and other various reasons.

Fabrication of Fe-Based Diamond Composites by Pressureless Infiltration

PubMed Central

Li, Meng; Sun, Youhong; Meng, Qingnan; Wu, Haidong; Gao, Ke; Liu, Baochang

2016-01-01

A metal-based matrix is usually used for the fabrication of diamond bits in order to achieve favorable properties and easy processing. In the effort to reduce the cost and to attain the desired bit properties, researchers have brought more attention to diamond composites. In this paper, Fe-based impregnated diamond composites for drill bits were fabricated by using a pressureless infiltration sintering method at 970 °C for 5 min. In addition, boron was introduced into Fe-based diamond composites. The influence of boron on the density, hardness, bending strength, grinding ratio, and microstructure was investigated. An Fe-based diamond composite with 1 wt % B has an optimal overall performance, the grinding ratio especially improving by 80%. After comparing with tungsten carbide (WC)-based diamond composites with and without 1 wt % B, results showed that the Fe-based diamond composite with 1 wt % B exhibits higher bending strength and wear resistance, being satisfactory to bit needs. PMID:28774124

PDC-TREM, a plasmacytoid dendritic cell-specific receptor, is responsible for augmented production of type I interferon.

PubMed

Watarai, Hiroshi; Sekine, Etsuko; Inoue, Sayo; Nakagawa, Ryusuke; Kaisho, Tsuneyasu; Taniguchi, Masaru

2008-02-26

Type I interferons (IFNs) derived from plasmacytoid dendritic cells (PDCs) are critical for antiviral responses; however, the mechanisms underlying their production remain unclear. We have identified a receptor, PDC-TREM, which is associated with Plexin-A1 (PlxnA1) on the PDC cell surface and is preferentially expressed after TLR-stimulation. Limited TLR signals induced PDC-TREM expression but failed to induce IFN-alpha production. However, when coupled with Sema6D, a ligand for Plexin-A1, limited TLR-stimulation resulted in PDC-TREM-mediated DAP12-dependent phosphorylation of phosphoinositide 3-kinase (PI3K) and extracellular regulated kinase (Erk) 1/2 at 6-9 h, and IFN-alpha was produced. Inhibition of PDC-TREM expression by pdctrem-shRNA, blocking of PDC-TREM-binding with PlxnA1 by PDC-TREM mAb, and DAP12 deficiency all resulted in greatly reduced PDC-TREM-dependent activation of signaling molecules and IFN-alpha production. Thus, PDC-TREM is responsible for IFN-alpha production, whereas TLR signals are essential for PDC-TREM expression.

Quantum key distribution with entangled photon sources

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

Ma Xiongfeng; Fung, Chi-Hang Fred; Lo, H.-K.

2007-07-15

A parametric down-conversion (PDC) source can be used as either a triggered single-photon source or an entangled-photon source in quantum key distribution (QKD). The triggering PDC QKD has already been studied in the literature. On the other hand, a model and a post-processing protocol for the entanglement PDC QKD are still missing. We fill in this important gap by proposing such a model and a post-processing protocol for the entanglement PDC QKD. Although the PDC model is proposed to study the entanglement-based QKD, we emphasize that our generic model may also be useful for other non-QKD experiments involving a PDCmore » source. Since an entangled PDC source is a basis-independent source, we apply Koashi and Preskill's security analysis to the entanglement PDC QKD. We also investigate the entanglement PDC QKD with two-way classical communications. We find that the recurrence scheme increases the key rate and the Gottesman-Lo protocol helps tolerate higher channel losses. By simulating a recent 144-km open-air PDC experiment, we compare three implementations: entanglement PDC QKD, triggering PDC QKD, and coherent-state QKD. The simulation result suggests that the entanglement PDC QKD can tolerate higher channel losses than the coherent-state QKD. The coherent-state QKD with decoy states is able to achieve highest key rate in the low- and medium-loss regions. By applying the Gottesman-Lo two-way post-processing protocol, the entanglement PDC QKD can tolerate up to 70 dB combined channel losses (35 dB for each channel) provided that the PDC source is placed in between Alice and Bob. After considering statistical fluctuations, the PDC setup can tolerate up to 53 dB channel losses.« less

Retained broken implants in the craniomaxillofacial skeleton.

PubMed

Nallathamby, Vigneswaran; Lee, Hanjing; Lin, Yap Yan; Lim, Jane; Ong, Wei Chen; Lim, Thiam-Chye

2014-06-01

Facial fracture patients are seen in a Level 1 trauma hospital. In our institution, we manage many patients with facial fractures and carry out more than 150 surgical procedures every year. Open reduction and internal fixation is our management of choice. All surgical procedures involve drilling of bone and implant insertion to keep the fractured bones in an anatomically reduced position to aid healing. Occasionally, drill bits used to create the pilot hole break and are embedded in the bone. We present a situation in which such an incident occurred and review the literature on retained broken implants and devices.

Investigating Created Properties of Nanoparticles Based Drilling Mud

NASA Astrophysics Data System (ADS)

Ghasemi, Nahid; Mirzaee, Mojtaba; Aghayari, Reza; Maddah, Heydar

2018-05-01

The success of drilling operations is heavily dependent on the drilling fluid. Drilling fluids cool down and lubricate the drill bit, remove cuttings, prevent formation damage, suspend cuttings and also cake off the permeable formation, thus retarding the passage of fluid into the formation. Typical micro or macro sized loss circulation materials (LCM) show limited success, especially in formations dominated by micropores, due to their relatively large sizes. Due to unique characteristics of nanoparticles such as their size and high surface area to volume ratio, they play an effective role in solving problems associated with the drilling fluid. In this study, we investigate the effect of adding Al2O3 and TiO2 nanoparticles into the drilling mud. Al2O3 and TiO2 nanoparticles were used in 20 and 60 nm of size and 0.05 wt% in concentration. Investigating the effects of temperature and pressure has shown that an increase in temperature can reduce the drilling mud rheological properties such as plastic viscosity, while an increase in pressure can enhance these properties. Also, the effects of pressure in high temperatures were less than those in low temperatures. Studying the effects of adding nanoparticles has shown that they can reduce the drilling mud rheological properties. Moreover, they can increase gel strength, reduce capillary suction time and decrease formation damage.

Controlling taphole depth in maple sap production research

Treesearch

Melvin R. Koelling; Barton M. Blum

1967-01-01

Because bark thickness of sugar maple trees varies considerably, the depth of tapholes for collecting maple sap should be varied accordingly to get the taphole depth that will produce the best sap flow. A system of removable collars on the drill bit is recommended as a means of regulating taphole depth in research studies.

Fluorescence studies on the interaction of choline-binding domain B of the major bovine seminal plasma protein, PDC-109 with phospholipid membranes.

PubMed

Damai, Rajani S; Anbazhagan, V; Rao, K Babu; Swamy, Musti J

2009-12-01

The microenvironment and accessibility of the tryptophan residues in domain B of PDC-109 (PDC-109/B) in the native state and upon ligand binding have been investigated by fluorescence quenching, time-resolved fluorescence and red-edge excitation shift (REES) studies. The increase in the intrinsic fluorescence emission intensity of PDC-109/B upon binding to lysophosphatidylcholine (Lyso-PC) micelles and dimyristoylphosphatidylcholine (DMPC) membranes was considerably less as compared to that observed with the whole PDC-109 protein. The degree of quenching achieved by different quenchers with PDC-109/B bound to Lyso-PC and DMPC membranes was significantly higher as compared to the full PDC-109 protein, indicating that membrane binding afforded considerably lesser protection to the tryptophan residues of domain B as compared to those in the full PDC-109 protein. Finally, changes in red-edge excitation shift (REES) seen with PDC-109/B upon binding to DMPC membranes and Lyso-PC micelles were smaller that the corresponding changes in the REES values observed for the full PDC-109. These results, taken together suggest that intact PDC-109 penetrates deeper into the hydrophobic parts of the membrane as compared to domain B alone, which could be the reason for the inability of PDC-109/B to induce cholesterol efflux, despite its ability to recognize choline phospholipids at the membrane surface.

A study of an assisting robot for mandible plastic surgery based on augmented reality.

PubMed

Shi, Yunyong; Lin, Li; Zhou, Chaozheng; Zhu, Ming; Xie, Le; Chai, Gang

2017-02-01

Mandible plastic surgery plays an important role in conventional plastic surgery. However, its success depends on the experience of the surgeons. In order to improve the effectiveness of the surgery and release the burden of surgeons, a mandible plastic surgery assisting robot, based on an augmented reality technique, was developed. Augmented reality assists surgeons to realize positioning. Fuzzy control theory was used for the control of the motor. During the process of bone drilling, both the drill bit position and the force were measured by a force sensor which was used to estimate the position of the drilling procedure. An animal experiment was performed to verify the effectiveness of the robotic system. The position error was 1.07 ± 0.27 mm and the angle error was 5.59 ± 3.15°. The results show that the system provides a sufficient accuracy with which a precise drilling procedure can be performed. In addition, under the supervision's feedback of the sensor, an adequate safety level can be achieved for the robotic system. The system realizes accurate positioning and automatic drilling to solve the problems encountered in the drilling procedure, providing a method for future plastic surgery.

Development of a Piezoelectric Rotary Hammer Drill

NASA Technical Reports Server (NTRS)

Domm, Lukas N.

2011-01-01

The Piezoelectric Rotary Hammer Drill is designed to core through rock using a combination of rotation and high frequency hammering powered by a single piezoelectric actuator. It is designed as a low axial preload, low mass, and low power device for sample acquisition on future missions to extraterrestrial bodies. The purpose of this internship is to develop and test a prototype of the Piezoelectric Rotary Hammer Drill in order to verify the use of a horn with helical or angled cuts as a hammering and torque inducing mechanism. Through an iterative design process using models in ANSYS Finite Element software and a Mason's Equivalent Circuit model in MATLAB, a horn design was chosen for fabrication based on the predicted horn tip motion, electromechanical coupling, and neutral plane location. The design was then machined and a test bed assembled. The completed prototype has proven that a single piezoelectric actuator can be used to produce both rotation and hammering in a drill string through the use of a torque inducing horn. Final data results include bit rotation produced versus input power, and best drilling rate achieved with the prototype.

Hole 504B reclaimed for future drilling

NASA Astrophysics Data System (ADS)

Leg 137 Scientific Drilling Party

Hole 504B, perhaps the most important in situ reference section for the structure and composition of the oceanic crust, has been reopened for future drilling and downhole measurements after remedial operations during Leg 137 of the Ocean Drilling Program. By far the deepest penetration into oceanic crust, Hole 504B had been feared lost when a large diamond bit and assorted hardware (“junk”) broke off in the bottom of the hole at the end of ODP Leg 111 in 1986. Since then ODP's drill ship, JOIDES Resolution, has circumnavigated the globe, with no opportunity to redress this situation. But the objective of deep penetration into the oceanic crust and the hole itself are considered so important by marine Earth scientists that remedial measures in Hole 504B were undertaken as soon as the drill ship returned to the eastern Pacific. These measures succeeded better than had been hoped. Hole 504B was reopened after less than a week of cleaning operations, which included grappling for the lost junk with tools to pull it from the hole (called “fishing”) and grinding or milling the junk away.

Theoretical analysis and design of hydro-hammer with a jet actuator: An engineering application to improve the penetration rate of directional well drilling in hard rock formations.

PubMed

He, Jiang-Fu; Liang, Yun-Pei; Li, Li-Jia; Luo, Yong-Jiang

2018-01-01

Rapid horizontal directional well drilling in hard or fractured formations requires efficient drilling technology. The penetration rate of conventional hard rock drilling technology in horizontal directional well excavations is relatively low, resulting in multiple overgrinding of drill cuttings in bottom boreholes. Conventional drilling techniques with reamer or diamond drill bit face difficulties due to the long construction periods, low penetration rates, and high engineering costs in the directional well drilling of hard rock. To improve the impact energy and penetration rate of directional well drilling in hard formations, a new drilling system with a percussive and rotary drilling technology has been proposed, and a hydro-hammer with a jet actuator has also been theoretically designed on the basis of the impulse hydro-turbine pressure model. In addition, the performance parameters of the hydro-hammer with a jet actuator have been numerically and experimentally analyzed, and the influence of impact stroke and pumped flow rate on the motion velocity and impact energy of the hydro-hammer has been obtained. Moreover, the designed hydro-hammer with a jet actuator has been applied to hard rock drilling in a trenchless drilling program. The motion velocity of the hydro-hammer ranges from 1.2 m/s to 3.19 m/s with diverse flow rates and impact strokes, and the motion frequency ranges from 10 Hz to 22 Hz. Moreover, the maximum impact energy of the hydro-hammer is 407 J, and the pumped flow rate is 2.3 m3/min. Thus, the average penetration rate of the optimized hydro-hammer improves by over 30% compared to conventional directional drilling in hard rock formations.

Theoretical analysis and design of hydro-hammer with a jet actuator: An engineering application to improve the penetration rate of directional well drilling in hard rock formations

PubMed Central

He, Jiang-fu; Li, Li-jia; Luo, Yong-jiang

2018-01-01

Rapid horizontal directional well drilling in hard or fractured formations requires efficient drilling technology. The penetration rate of conventional hard rock drilling technology in horizontal directional well excavations is relatively low, resulting in multiple overgrinding of drill cuttings in bottom boreholes. Conventional drilling techniques with reamer or diamond drill bit face difficulties due to the long construction periods, low penetration rates, and high engineering costs in the directional well drilling of hard rock. To improve the impact energy and penetration rate of directional well drilling in hard formations, a new drilling system with a percussive and rotary drilling technology has been proposed, and a hydro-hammer with a jet actuator has also been theoretically designed on the basis of the impulse hydro-turbine pressure model. In addition, the performance parameters of the hydro-hammer with a jet actuator have been numerically and experimentally analyzed, and the influence of impact stroke and pumped flow rate on the motion velocity and impact energy of the hydro-hammer has been obtained. Moreover, the designed hydro-hammer with a jet actuator has been applied to hard rock drilling in a trenchless drilling program. The motion velocity of the hydro-hammer ranges from 1.2 m/s to 3.19 m/s with diverse flow rates and impact strokes, and the motion frequency ranges from 10 Hz to 22 Hz. Moreover, the maximum impact energy of the hydro-hammer is 407 J, and the pumped flow rate is 2.3 m3/min. Thus, the average penetration rate of the optimized hydro-hammer improves by over 30% compared to conventional directional drilling in hard rock formations. PMID:29768421

Force and torque modelling of drilling simulation for orthopaedic surgery.

PubMed

MacAvelia, Troy; Ghasempoor, Ahmad; Janabi-Sharifi, Farrokh

2014-01-01

The advent of haptic simulation systems for orthopaedic surgery procedures has provided surgeons with an excellent tool for training and preoperative planning purposes. This is especially true for procedures involving the drilling of bone, which require a great amount of adroitness and experience due to difficulties arising from vibration and drill bit breakage. One of the potential difficulties with the drilling of bone is the lack of consistent material evacuation from the drill's flutes as the material tends to clog. This clogging leads to significant increases in force and torque experienced by the surgeon. Clogging was observed for feed rates greater than 0.5 mm/s and spindle speeds less than 2500 rpm. The drilling simulation systems that have been created to date do not address the issue of drill flute clogging. This paper presents force and torque prediction models that account for this phenomenon. The two coefficients of friction required by these models were determined via a set of calibration experiments. The accuracy of both models was evaluated by an additional set of validation experiments resulting in average R² regression correlation values of 0.9546 and 0.9209 for the force and torque prediction models, respectively. The resulting models can be adopted by haptic simulation systems to provide a more realistic tactile output.

Coordination properties of tridentate (N,O,O) heterocyclic alcohol (PDC) with Cu(II). Mixed ligand complex formation reactions of Cu(II) with PDC and some bio-relevant ligands.

PubMed

El-Sherif, Ahmed A; Shoukry, Mohamed M

2007-03-01

The formation equilibria of copper(II) complexes and the ternary complexes Cu(PDC)L (PDC=2,6-bis-(hydroxymethyl)-pyridine, HL=amino acid, amides or DNA constituents) have been investigated. Ternary complexes are formed by a simultaneous mechanism. The results showed the formation of Cu(PDC)L, Cu(PDC, H(-1))(L) and Cu(PDC, H(-2))(L) complexes. The concentration distribution of the complexes in solution is evaluated as a function of pH. The effect of dioxane as a solvent on the protonation constant of PDC and the formation constants of Cu(II) complexes are discussed. The thermodynamic parameters DeltaH degrees and DeltaS degrees calculated from the temperature dependence of the equilibrium constants are investigated.

Plasmacytoid Dendritic Cell Dynamics Tune Interferon-Alfa Production in SIV-Infected Cynomolgus Macaques

PubMed Central

Bruel, Timothée; Dupuy, Stéphanie; Démoulins, Thomas; Rogez-Kreuz, Christine; Dutrieux, Jacques; Corneau, Aurélien; Cosma, Antonio; Cheynier, Rémi; Dereuddre-Bosquet, Nathalie; Le Grand, Roger; Vaslin, Bruno

2014-01-01

IFN-I production is a characteristic of HIV/SIV primary infections. However, acute IFN-I plasma concentrations rapidly decline thereafter. Plasmacytoid dendritic cells (pDC) are key players in this production but primary infection is associated with decreased responsiveness of pDC to TLR 7 and 9 triggering. IFNα production during primary SIV infection contrasts with increased pDC death, renewal and dysfunction. We investigated the contribution of pDC dynamics to both acute IFNα production and the rapid return of IFNα concentrations to pre-infection levels during acute-to-chronic transition. Nine cynomolgus macaques were infected with SIVmac251 and IFNα-producing cells were quantified and characterized. The plasma IFN-I peak was temporally associated with the presence of IFNα+ pDC in tissues but IFN-I production was not detectable during the acute-to-chronic transition despite persistent immune activation. No IFNα+ cells other than pDC were detected by intracellular staining. Blood-pDC and peripheral lymph node-pDC both lost IFNα− production ability in parallel. In blood, this phenomenon correlated with an increase in the counts of Ki67+-pDC precursors with no IFNα production ability. In tissues, it was associated with increase of both activated pDC and KI67+-pDC precursors, none of these being IFNα+ in vivo. Our findings also indicate that activation/death-driven pDC renewal rapidly blunts acute IFNα production in vivo: pDC sub-populations with no IFNα-production ability rapidly increase and shrinkage of IFNα production thus involves both early pDC exhaustion, and increase of pDC precursors. PMID:24497833

Impaired plasmacytoid dendritic cell (PDC)-NK cell activity in viremic human immunodeficiency virus infection attributable to impairments in both PDC and NK cell function.

PubMed

Conry, Sara J; Milkovich, Kimberly A; Yonkers, Nicole L; Rodriguez, Benigno; Bernstein, Helene B; Asaad, Robert; Heinzel, Frederick P; Tary-Lehmann, Magdalena; Lederman, Michael M; Anthony, Donald D

2009-11-01

Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infections impair plasmacytoid dendritic cell (PDC) and natural killer (NK) cell subset numbers and functions, though little is known about PDC-NK cell interactions during these infections. We evaluated PDC-dependent NK cell killing and gamma interferon (IFN-gamma) and granzyme B production, using peripheral blood mononuclear cell (PBMC)-based and purified cell assays of samples from HCV- and HIV-infected subjects. CpG-enhanced PBMC killing and IFN-gamma and granzyme B activity (dependent on PDC and NK cells) were impaired in viremic HIV infection. In purified PDC-NK cell culture experiments, CpG-enhanced, PDC-dependent NK cell activity was cell contact and IFN-alpha dependent, and this activity was impaired in viremic HIV infection but not in HCV infection. In heterologous PDC-NK cell assays, impaired PDC-NK cell killing activity was largely attributable to an NK cell defect, while impaired PDC-NK cell IFN-gamma-producing activity was attributable to both PDC and NK cell defects. Additionally, the response of NK cells to direct IFN-alpha stimulation was defective in viremic HIV infection, and this defect was not attributable to diminished IFN-alpha receptor expression, though IFN-alpha receptor and NKP30 expression was closely associated with killer activity in viremic HIV infection but not in healthy controls. These data indicate that during uncontrolled HIV infection, PDC-dependent NK cell function is impaired, which is in large part attributable to defective IFN-alpha-induced NK cell activity and not to altered IFN-alpha receptor, NKP30, NKP44, NKP46, or NKG2D expression.

An Ultrasonic Sampler and Sensor Platform for In-Situ Astrobiological Exploration

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoaz E.; Bao, X.; Chang, Z.; Sherrit, S.

2003-01-01

The search for existing or past life in the Universe is one of the most important objectives of NASA's mission. In support of this objective, ultrasonic based mechanisms are currently being developed at JPL to allow probing and sampling rocks as well as perform as a sensor platform for in-situ astrobiological analysis. The technology is based on the novel Ultrasonic/Sonic Driller/Corer (USDC), which requires low axial force, thereby overcoming one of the major limitations of planetary sampling in low gravity using conventional drills. The USDC was demonstrated to: 1) drill ice and various rocks including granite, diorite, basalt and limestone, 2) not require bit sharpening, and 3) operate at high and low temperatures. The capabilities that are being investigated including probing the ground to select sampling sites, collecting various forms of samples, and hosting sensors for measuring chemical/physical properties. A series of modifications of the USDC basic configuration were implemented leading an ultrasonic abrasion tool (URAT), Ultrasonic Gopher for deep Drilling, and the lab-on-a-drill.

Reaching 1 m deep on Mars: the Icebreaker drill.

PubMed

Zacny, K; Paulsen, G; McKay, C P; Glass, B; Davé, A; Davila, A F; Marinova, M; Mellerowicz, B; Heldmann, J; Stoker, C; Cabrol, N; Hedlund, M; Craft, J

2013-12-01

The future exploration of Mars will require access to the subsurface, along with acquisition of samples for scientific analysis and ground-truthing of water ice and mineral reserves for in situ resource utilization. The Icebreaker drill is an integral part of the Icebreaker mission concept to search for life in ice-rich regions on Mars. Since the mission targets Mars Special Regions as defined by the Committee on Space Research (COSPAR), the drill has to meet the appropriate cleanliness standards as requested by NASA's Planetary Protection Office. In addition, the Icebreaker mission carries life-detection instruments; and in turn, the drill and sample delivery system have to meet stringent contamination requirements to prevent false positives. This paper reports on the development and testing of the Icebreaker drill, a 1 m class rotary-percussive drill and triple redundant sample delivery system. The drill acquires subsurface samples in short, approximately 10 cm bites, which makes the sampling system robust and prevents thawing and phase changes in the target materials. Autonomous drilling, sample acquisition, and sample transfer have been successfully demonstrated in Mars analog environments in the Arctic and the Antarctic Dry Valleys, as well as in a Mars environmental chamber. In all environments, the drill has been shown to perform at the "1-1-100-100" level; that is, it drilled to 1 m depth in approximately 1 hour with less than 100 N weight on bit and approximately 100 W of power. The drilled substrate varied and included pure ice, ice-rich regolith with and without rocks and with and without 2% perchlorate, and whole rocks. The drill is currently at a Technology Readiness Level (TRL) of 5. The next-generation Icebreaker drill weighs 10 kg, which is representative of the flightlike model at TRL 5/6.

IL-27 Production and STAT3-Dependent Upregulation of B7-H1 Mediate Immune Regulatory Functions of Liver Plasmacytoid DC1

PubMed Central

Matta, Benjamin M.; Raimondi, Giorgio; Rosborough, Brian R.; Sumpter, Tina L.; Thomson, Angus W.

2012-01-01

Plasmacytoid (p) dendritic cells (DC) are highly-specialized APC that, in addition to their well-recognized role in anti-viral immunity, also regulate immune responses. Liver-resident pDC are considerably less immunostimulatory than those from secondary lymphoid tissues and are equipped to promote immune tolerance/regulation through various mechanisms. IL-27 is an IL-12-family cytokine that regulates the function of both APC and T cells, although little is known about its role in pDC immunobiology. In this study, we show that mouse liver pDC express higher levels of IL-27p28 and EBV-induced protein (Ebi)3 compared to splenic pDC. Both populations of pDC express the IL-27Rα/WSX-1; however, only liver pDC significantly upregulate expression of the co-regulatory molecule B7 homolog-1 (B7-H1) in response to IL-27. Inhibition of STAT3 activation completely abrogates IL-27-induced upregulation of B7-H1 expression on liver pDC. Liver pDC treated with IL-27 increase the percentage of CD4+Foxp3+ T cells in MLR, which is dependent upon expression of B7-H1. pDC from Ebi3-deficient mice lacking functional IL-27, show increased capacity to stimulate allogeneic T cell proliferation and IFN-γ production in MLR. Liver but not spleen pDC suppress delayed-type hypersensitivity responses to OVA, an effect that is lost with Ebi3−/− and B7-H1−/− liver pDC compared to wild-type (WT) liver pDC. These data suggest that IL-27 signaling in pDC promotes their immunoregulatory function and that IL-27 produced by pDC contributes to their capacity to regulate immuneresponses in vitro and in vivo. PMID:22508931

An Evaluation of the Performance Diagnostic Checklist-Human Services (PDC-HS) Across Domains.

PubMed

Wilder, David A; Lipschultz, Joshua; Gehrman, Chana

2018-06-01

The Performance Diagnostic Checklist-Human Services (PDC-HS) is an informant-based tool designed to assess the environmental variables that contribute to poor employee performance in human service settings. Although the PDC-HS has been shown to effectively identify variables contributing to problematic performance, interventions based on only two of the four PDC-HS domains have been evaluated to date. In addition, the extent to which PDC-HS-indicated interventions are more effective than nonindicated interventions for two domains remains unclear. In the current study, we administered the PDC-HS to supervisors to assess the variables contributing to infrequent teaching of verbal operants and use of a timer by therapists at a center-based autism treatment program. Each of the four PDC-HS domains was identified as contributing to poor performance for at least one therapist. We then evaluated PDC-HS-indicated interventions for each domain. In addition, to assess the predictive validity of the tool, we evaluated various nonindicated interventions prior to implementing a PDC-HS-indicated intervention for two of the four domains. Results suggest that the PDC-HS-indicated interventions were effective across all four domains and were more effective than the nonindicated interventions for the two domains for which they were evaluated. Results are discussed in terms of the utility of the PDC-HS to identify appropriate interventions to manage therapist performance in human service settings.

Characterizing the Weeks Island Salt Dome drilling of and seismic measurements from boreholes

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

Sattler, A.R.; Harding, R.S.; Jacobson, R.D.

1996-10-01

A sinkhole 36 ft across, 30 ft deep was first observed in the alluvium over the Weeks Island Salt Dome (salt mine converted for oil storage by US Strategic Petroleum Reserve) May 1992. Four vertical, two slanted boreholes were drilled for diagnostics. Crosswell seismic data were generated; the velocity images suggest that the sinkhole collapse is complicated, not a simple vertical structure. The coring operation was moderately difficult; limited core was obtained through the alluvium, and the quality of the salt core from the first two vertical wells was poor. Core quality improved with better bit selection, mud, and drillingmore » method. The drilling fluid program provided fairly stable holes allowing open hole logs to be run. All holes were cemented successfully (although it took 3 attempts in one case).« less

Stock room, just off the large first floor machine ship. ...

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

Stock room, just off the large first floor machine ship. Here were stored various cutting edges and drill bits used on the machines. Some raw materials were stored here as well, along with nuts and bolts, machine screws, etc. - Thomas A. Edison Laboratories, Building No. 5, Main Street & Lakeside Avenue, West Orange, Essex County, NJ

Associations of Frequency and Duration of Patient-Doctor Contact in Hemodialysis Facilities with Mortality

PubMed Central

Karaboyas, Angelo; Robinson, Bruce M.; Li, Yun; Fukuhara, Shunichi; Bieber, Brian A.; Rayner, Hugh C.; Andreucci, Vittorio E.; Pisoni, Ronald L.; Port, Friedrich K.; Morgenstern, Hal; Akizawa, Tadao; Saran, Rajiv

2013-01-01

It is unknown whether regular patient-doctor contact (PDC) contributes to better outcomes for patients undergoing hemodialysis. Here, we analyzed the associations between frequency and duration of PDC during hemodialysis treatments with clinical outcomes among 24,498 patients from 778 facilities in the international Dialysis Outcomes and Practice Patterns Study (DOPPS). The typical facility PDC frequency, estimated by facility personnel, was high (more than once per week) for 55% of facilities, intermediate (once per week) for 24%, and low (less than once per week) for 21%. The mean ± SD estimated duration of a typical interaction between patient and physician was 7.7±5.6 minutes. PDC frequency and duration varied across DOPPS phases and countries; the proportion of facilities with high PDC frequency was 17% in the United States and 73% across the other countries. Compared with high PDC frequency, the adjusted hazard ratio (HR) for all-cause mortality was 1.06 (95% confidence interval [CI], 0.96 to 1.17) for intermediate PDC frequency and 1.11 (95% CI, 1.01 to 1.23) for low PDC frequency (P=0.03 for trend). Furthermore, each 5-minutes-shorter duration of PDC was associated with a 5% higher risk for death, on average (HR, 1.05; 95% CI, 1.01 to 1.09), adjusted for PDC frequency and other covariates. Multivariable analyses also suggested modest inverse associations between both PDC frequency and duration with hospitalization but not with kidney transplantation. Taken together, these results suggest that policies supporting more frequent and longer duration of PDC may improve patient outcomes in hemodialysis. PMID:23886592

PDC-E3BP is not a dominant T-cell autoantigen in primary biliary cirrhosis.

PubMed

McHugh, Anna; Robe, Amanda J; Palmer, Jeremy M; Jones, David E J

2006-05-01

Autoantibody responses reactive with the E2 and E3BP components of pyruvate dehydrogenase complex (PDC), which characterise primary biliary cirrhosis (PBC) crossreact, precluding the identification, from serological studies, of the antigen to which the principal breakdown of tolerance occurs. Although autoreactive T-cell responses to PDC-E2 have been well characterised it is, at present, unclear whether T-cell tolerance breakdown also occurs to PDC-E3BP. The aims of this study were to characterise autoreactive T-cell responses to PDC-E3BP in PBC and potential factors regulating their expression. Peripheral blood T-cell proliferative responses to purified recombinant human PDC-E2 and PDC-E3BP at a range of concentrations were characterised in PBC patients and control subjects. T-cell proliferative responses to both E2 and E3BP were absent from control subjects (median peak stimulation index (SI) to PDC-E2 1.2 [range 0.3-1.9], 0/10 positive (SI>2.32), median peak SI to PDC-E3BP 1.1 [0.7-2.1

Plasmacytoid Dendritic Cell Infection and Sensing Capacity during Pathogenic and Nonpathogenic Simian Immunodeficiency Virus Infection

PubMed Central

Jochems, Simon P.; Jacquelin, Beatrice; Chauveau, Lise; Huot, Nicolas; Petitjean, Gaël; Lepelley, Alice; Liovat, Anne-Sophie; Ploquin, Mickaël J.; Cartwright, Emily K.; Bosinger, Steven E.; Silvestri, Guido; Barré-Sinoussi, Françoise; Lebon, Pierre; Schwartz, Olivier

2015-01-01

ABSTRACT Human immunodeficiency virus (HIV) in humans and simian immunodeficiency virus (SIV) in macaques (MAC) lead to chronic inflammation and AIDS. Natural hosts, such as African green monkeys (AGM) and sooty mangabeys (SM), are protected against SIV-induced chronic inflammation and AIDS. Here, we report that AGM plasmacytoid dendritic cells (pDC) express extremely low levels of CD4, unlike MAC and human pDC. Despite this, AGM pDC efficiently sensed SIVagm, but not heterologous HIV/SIV isolates, indicating a virus-host adaptation. Moreover, both AGM and SM pDC were found to be, in contrast to MAC pDC, predominantly negative for CCR5. Despite such limited CD4 and CCR5 expression, lymphoid tissue pDC were infected to a degree similar to that seen with CD4+ T cells in both MAC and AGM. Altogether, our finding of efficient pDC infection by SIV in vivo identifies pDC as a potential viral reservoir in lymphoid tissues. We discovered low expression of CD4 on AGM pDC, which did not preclude efficient sensing of host-adapted viruses. Therefore, pDC infection and efficient sensing are not prerequisites for chronic inflammation. The high level of pDC infection by SIVagm suggests that if CCR5 paucity on immune cells is important for nonpathogenesis of natural hosts, it is possibly not due to its role as a coreceptor. IMPORTANCE The ability of certain key immune cell subsets to resist infection might contribute to the asymptomatic nature of simian immunodeficiency virus (SIV) infection in its natural hosts, such as African green monkeys (AGM) and sooty mangabeys (SM). This relative resistance to infection has been correlated with reduced expression of CD4 and/or CCR5. We show that plasmacytoid dendritic cells (pDC) of natural hosts display reduced CD4 and/or CCR5 expression, unlike macaque pDC. Surprisingly, this did not protect AGM pDC, as infection levels were similar to those found in MAC pDC. Furthermore, we show that AGM pDC did not consistently produce type I interferon (IFN-I) upon heterologous SIVmac/HIV type 1 (HIV-1) encounter, while they sensed autologous SIVagm isolates. Pseudotyping SIVmac/HIV-1 overcame this deficiency, suggesting that reduced uptake of heterologous viral strains underlays this lack of sensing. The distinct IFN-I responses depending on host species and HIV/SIV isolates reveal the host/virus species specificity of pDC sensing. PMID:25903334

A PFC3D-based numerical simulation of cutting load for lunar rock simulant and experimental validation

NASA Astrophysics Data System (ADS)

Li, Peng; Jiang, Shengyuan; Tang, Dewei; Xu, Bo

2017-05-01

For sake of striking a balance between the need of drilling efficiency and the constrains of power budget on the moon, the penetrations per revolution of drill bit are generally limited in the range around 0.1 mm, and besides the geometric angle of the cutting blade need to be well designed. This paper introduces a simulation approach based on PFC3D (particle flow code 3 dimensions) for analyzing the cutting load feature on lunar rock simulant, which is derived from different geometric-angle blades with a small cutting depth. The mean values of the cutting force of five blades in the survey region (four on the boundary points and one on the center point) are selected as the macroscopic responses of model. The method of experimental design which includes Plackett-Burman (PB) design and central composite design (CCD) method is adopted in the matching procedure of microparameters in PFC model. Using the optimization method of enumeration, the optimum set of microparameters is acquired. Then, the experimental validation is implemented by using other twenty-five blades with different geometric angles, and the results from both simulations and laboratory tests give fair agreements. Additionally, the rock breaking process cut by different blades are quantified from simulation analysis. This research provides the theoretical support for the refinement of the rock cutting load prediction and the geometric design of cutting blade on the drill bit.

Experimental investigation of temperature rise in bone drilling with cooling: A comparison between modes of without cooling, internal gas cooling, and external liquid cooling.

PubMed

Shakouri, Ehsan; Haghighi Hassanalideh, Hossein; Gholampour, Seifollah

2018-01-01

Bone fracture occurs due to accident, aging, and disease. For the treatment of bone fractures, it is essential that the bones are kept fixed in the right place. In complex fractures, internal fixation or external methods are used to fix the fracture position. In order to immobilize the fracture position and connect the holder equipment to it, bone drilling is required. During the drilling of the bone, the required forces to chip formation could cause an increase in the temperature. If the resulting temperature increases to 47 °C, it causes thermal necrosis of the bone. Thermal necrosis decreases bone strength in the hole and, subsequently, due to incomplete immobilization of bone, fracture repair is not performed correctly. In this study, attempts have been made to compare local temperature increases in different processes of bone drilling. This comparison has been done between drilling without cooling, drilling with gas cooling, and liquid cooling on bovine femur. Drilling tests with gas coolant using direct injection of CO 2 and N 2 gases were carried out by internal coolant drill bit. The results showed that with the use of gas coolant, the elevation of temperature has limited to 6 °C and the thermal necrosis is prevented. Maximum temperature rise reached in drilling without cooling was 56 °C, using gas and liquid coolant, a maximum temperature elevation of 43 °C and 42 °C have been obtained, respectively. This resulted in decreased possibility of thermal necrosis of bone in drilling with gas and liquid cooling. However, the results showed that the values obtained with the drilling method with direct gas cooling are independent of the rotational speed of drill.

Flexible roof drill for low coal. Volume 2. Phase III and Phase IV

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

Shoup, N.H.

1977-09-01

Design specifications were developed for a flexible drilling and bolting system. The system configuration is based on the use of the Galis dual-boom roof drill as a vehicle for the drilling/bolting system. The WSU Flex-drill drivehead is mounted on the Galis drill boom and the Galis parts are modified to accommodate the revised system. The flexible drillhead supports a bolt bender/inserter designed by Bendix Corporation and is integrated into the system operation. A supplemental bolt thruster was designed to complete insertion of the roof bolt following operation and removal of the Bendix bender from the bolt shank. The complete cyclemore » of drilling a 1-3/8-in. diameter bolt hole, bending a roof bolt into the hole, thrusting the bolt head and washer to the roof surface, and final torquing of the bolt is manually controlled by the operator located in the new position behind the bolting line. The new operating position is beneath newly bolted roof in a safer location in back of the stab jack ad roof jacks positioning the drill boom and drivehead. The Flex-drill/bolting system prototype was constructed from both purchased components and parts specially fabricated in the shops for this design. This unit was assembled and test-operated with appropriate support equipment in a laboratory test stand. Numerous test holes were drilled in blocks of concrete at feed rates of 5 ft/min with drill rotation speeds of 360 rpm. The drill feeds uniformly and cuts smoothly with no difficulty in collection of dust or clogging of the drill bit. The holes drilled were straight, as evidence by passage of a 1-1/4-in. diameter bar full depth into the hole with no binding or evidence of curvature. The flexible drill is capable of drilling 8-ft-deep roof bolt holes in low coal 36 in. in height.« less

[Clinical aspects, imaging and neuropathology of Kii ALS/PDC].

PubMed

Kokubo, Yasumasa

2007-11-01

During 1996 and 2006, we examined clinically 37 patients and neuropathologically 13 autopsy cases with amyotrophic lateral sclerosis/parkinsonism-dementia complex of the Kii peninsula (Kii ALS/PDC). The ages of onset were between 52 years and 74 years (mean age: 65.3 years). The male to female ratio was 1:1.85. The ratio of positive family history where ALS or PDC occurred within the fourth degree of the relatives was 78.4% in the patients with Kii ALS/PDC. The average duration of the illness was 6.47 years. Kii ALS/PDC was divided into five clinical subtypes, pure ALS form, ALS with dementia form, PDC with parkinsonism predominant form, PDC with dementia predominant form (that is called late-life dementia in Guam) and PDC with ALS features form. Unique pigmentary retinopathy was found in 33.3% of the patients with Kii ALS/PDC. CT/MRI images showed atrophy of the frontal and temporal lobes and SPECT images showed a decrease in the blood flow of the frontal and temporal lobes. The cardiac 123I-MIBG uptake was decreased in 4 out of 8 patients with ALS/PDC and the decrease in uptake correlated with the modified Hoehn-Yahr staging. The cardinal neuropathological features of Kii ALS/PDC were abundant neurofibrillary tangles (NFTs) associated with loss of nerve cells in the cerebral cortex and the brain stem, and findings of ALS neuropathology. Ultrastructurally, NFTs consisted of paired helical filaments. Tau protein, a main component of NFTs, was consisted of 3R and 4R tau isoforms, and phosphoryrated at 18 sites of tau phosphoryrated sites. The neurons of dentate gyrus of hippocampus and anterior horn cells were stained with anti-TDP-43 antibody. The clinical and neuropathological aspects of Kii ALS/PDC are regarded as being identical with those of Guam ALS/PDC.

Peoria Disposal Co.`s PDC Laboratories: Analyzing and cleaning up -- Literally

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

McAdams, C.L.

1995-10-01

In the early 1980s, says Royal Coulter, president and CEO of Peoria Disposal Co. (PDC, Peoria, IL), many PDC customers were unfamiliar with the methods required for the proper characterization of then newly regulated hazardous wastes. So in early 1981, to expedite permitting and, ultimately, acceptance of waste by PDC, a lab was set up so the company could step in and provide the needed services. By focusing on the delivery of quality services in the analysis of groundwater, wastewater, and solid waste for PDC, Coulter says, the laboratory soon developed into a successful and independent commercial operation. In Julymore » of 1981, PDC Laboratories was incorporated as an independent environmental analytical laboratory. PDC Labs is a subsidiary of PDC Technical Services, Inc., which provides environmental consulting and site remediation services, and is itself a wholly-owned subsidiary of Coulter Companies, Inc. Peoria Disposal offers solid waste disposal, industrial waste water treatment, waste stabilization, transportation services, and brokerage services.« less

Type I interferon regulates pDC maturation and Ly49Q expression.

PubMed

Toma-Hirano, Makiko; Namiki, Sahori; Miyatake, Shoichiro; Arai, Ken-Ichi; Kamogawa-Schifter, Yumiko

2007-10-01

Ly49Q is expressed on peripheral mouse plasmacytoid dendritic cells (pDC). Immature Ly49Q-negative pDC precursors acquire Ly49Q in the bone marrow and then migrate into the periphery. While searching for molecules that regulate pDC maturation, we found that type I interferon (IFN) inhibited Ly49Q acquisition in vitro. Infections that induce type I IFN production by cells other than pDC (a condition mimicked by poly(I:C) injection in vivo) increase the prevalence of Ly49Q(-) pDC in the bone marrow and peripheral lymphoid organs in wild-type but not IFN-alpha/beta receptor knockout BALB/c mice. Moreover, in vivo exposure to type I IFN causes some Ly49Q(-), but not Ly49Q(+), pDC to convert to conventional DC, defined as B220(-) CD11c(+) CD11b(+) cells. These data suggest that type I IFN regulates pDC development and affects their distribution in the body.

Hepatitis B Virus Lacks Immune Activating Capacity, but Actively Inhibits Plasmacytoid Dendritic Cell Function

PubMed Central

Woltman, Andrea M.; Shi, Cui C.; Janssen, Harry L. A.

2011-01-01

Chronic hepatitis B virus (HBV) infection is caused by inadequate anti-viral immunity. Activation of plasmacytoid dendritic cells (pDC) leading to IFNα production is important for effective anti-viral immunity. Hepatitis B virus (HBV) infection lacks IFNα induction in animal models and patients and chronic HBV patients display impaired IFNα production by pDC. Therefore, HBV and HBV-derived proteins were examined for their effect on human pDC in vitro. In addition, the in vitro findings were compared to the function of pDC derived from chronic HBV patients ex vivo. In contrast to other viruses, HBV did not activate pDC. Moreover, HBV and HBsAg abrogated CpG-A/TLR9-induced, but not Loxoribine/TLR7-induced, mTOR-mediated S6 phosphorylation, subsequent IRF7 phosphorylation and IFNα gene transcription. HBV/HBsAg also diminished upregulation of co-stimulatory molecules, production of TNFα, IP-10 and IL-6 and pDC-induced NK cell function, whereas TLR7-induced pDC function was hardly affected. In line, HBsAg preferentially bound to TLR9-triggered pDC demonstrating that once pDC are able to bind HBV/HBsAg, the virus exerts its immune regulatory effect. HBV not only directly interfered with pDC function, but also indirectly by interfering with monocyte-pDC interaction. Also HBeAg diminished pDC function to a certain extent, but via another unknown mechanism. Interestingly, patients with HBeAg-positive chronic hepatitis B displayed impaired CpG-induced IFNα production by pDC without significant alterations in Loxoribine-induced pDC function compared to HBeAg-negative patients and healthy controls. The lack of activation and the active inhibition of pDC by HBV may both contribute to HBV persistence. The finding that the interaction between pDC and HBV may change upon activation may aid in the identification of a scavenging receptor supporting immunosuppressive effects of HBV and also in the design of novel treatment strategies for chronic HBV. PMID:21246041

The Use of the Performance Diagnostic Checklist-Human Services to Assess and Improve the Job Performance of Individuals with Intellectual Disabilities.

PubMed

Smith, Madison; Wilder, David A

2018-06-01

The Performance Diagnostic Checklist-Human Services (PDC-HS) is an informant-based tool designed to identify the variables responsible for performance problems. To date, the PDC-HS has not been examined with individuals with intellectual disabilities. In the current study, two supervisors with intellectual disabilities completed the PDC-HS to assess the productivity of two supervisees with disabilities who performed a pricing task in a thrift store. The PDC-HS suggested that performance deficits were due to a lack of training; a PDC-HS-indicated intervention was effective to increase accurate pricing. • The PDC-HS is an informant-based tool designed to identify the variables responsible for employee performance problems in human service settings. • The PDC-HS can be completed by some individuals with intellectual disabilities in a supervisory position to identify the variables responsible for problematic job performance among their supervisees. • A PDC-HS indicated intervention was demonstrated to be effective to improve the job performance of individuals with disabilities. • The PDC-HS may be a useful tool to support performance improvement and job maintenance among individuals with intellectual disabilities.

Reductive evolution and the loss of PDC/PAS domains from the genus Staphylococcus

PubMed Central

2013-01-01

Background The Per-Arnt-Sim (PAS) domain represents a ubiquitous structural fold that is involved in bacterial sensing and adaptation systems, including several virulence related functions. Although PAS domains and the subclass of PhoQ-DcuS-CitA (PDC) domains have a common structure, there is limited amino acid sequence similarity. To gain greater insight into the evolution of PDC/PAS domains present in the bacterial kingdom and staphylococci in specific, the PDC/PAS domains from the genomic sequences of 48 bacteria, representing 5 phyla, were identified using the sensitive search method based on HMM-to-HMM comparisons (HHblits). Results A total of 1,007 PAS domains and 686 PDC domains distributed over 1,174 proteins were identified. For 28 Gram-positive bacteria, the distribution, organization, and molecular evolution of PDC/PAS domains were analyzed in greater detail, with a special emphasis on the genus Staphylococcus. Compared to other bacteria the staphylococci have relatively fewer proteins (6–9) containing PDC/PAS domains. As a general rule, the staphylococcal genomes examined in this study contain a core group of seven PDC/PAS domain-containing proteins consisting of WalK, SrrB, PhoR, ArlS, HssS, NreB, and GdpP. The exceptions to this rule are: 1) S. saprophyticus lacks the core NreB protein; 2) S. carnosus has two additional PAS domain containing proteins; 3) S. epidermidis, S. aureus, and S. pseudintermedius have an additional protein with two PDC domains that is predicted to code for a sensor histidine kinase; 4) S. lugdunensis has an additional PDC containing protein predicted to be a sensor histidine kinase. Conclusions This comprehensive analysis demonstrates that variation in PDC/PAS domains among bacteria has limited correlations to the genome size or pathogenicity; however, our analysis established that bacteria having a motile phase in their life cycle have significantly more PDC/PAS-containing proteins. In addition, our analysis revealed a tremendous amount of variation in the number of PDC/PAS-containing proteins within genera. This variation extended to the Staphylococcus genus, which had between 6 and 9 PDC/PAS proteins and some of these appear to be previously undescribed signaling proteins. This latter point is important because most staphylococcal proteins that contain PDC/PAS domains regulate virulence factor synthesis or antibiotic resistance. PMID:23902280

Reductive evolution and the loss of PDC/PAS domains from the genus Staphylococcus.

PubMed

Shah, Neethu; Gaupp, Rosmarie; Moriyama, Hideaki; Eskridge, Kent M; Moriyama, Etsuko N; Somerville, Greg A

2013-07-31

The Per-Arnt-Sim (PAS) domain represents a ubiquitous structural fold that is involved in bacterial sensing and adaptation systems, including several virulence related functions. Although PAS domains and the subclass of PhoQ-DcuS-CitA (PDC) domains have a common structure, there is limited amino acid sequence similarity. To gain greater insight into the evolution of PDC/PAS domains present in the bacterial kingdom and staphylococci in specific, the PDC/PAS domains from the genomic sequences of 48 bacteria, representing 5 phyla, were identified using the sensitive search method based on HMM-to-HMM comparisons (HHblits). A total of 1,007 PAS domains and 686 PDC domains distributed over 1,174 proteins were identified. For 28 Gram-positive bacteria, the distribution, organization, and molecular evolution of PDC/PAS domains were analyzed in greater detail, with a special emphasis on the genus Staphylococcus. Compared to other bacteria the staphylococci have relatively fewer proteins (6-9) containing PDC/PAS domains. As a general rule, the staphylococcal genomes examined in this study contain a core group of seven PDC/PAS domain-containing proteins consisting of WalK, SrrB, PhoR, ArlS, HssS, NreB, and GdpP. The exceptions to this rule are: 1) S. saprophyticus lacks the core NreB protein; 2) S. carnosus has two additional PAS domain containing proteins; 3) S. epidermidis, S. aureus, and S. pseudintermedius have an additional protein with two PDC domains that is predicted to code for a sensor histidine kinase; 4) S. lugdunensis has an additional PDC containing protein predicted to be a sensor histidine kinase. This comprehensive analysis demonstrates that variation in PDC/PAS domains among bacteria has limited correlations to the genome size or pathogenicity; however, our analysis established that bacteria having a motile phase in their life cycle have significantly more PDC/PAS-containing proteins. In addition, our analysis revealed a tremendous amount of variation in the number of PDC/PAS-containing proteins within genera. This variation extended to the Staphylococcus genus, which had between 6 and 9 PDC/PAS proteins and some of these appear to be previously undescribed signaling proteins. This latter point is important because most staphylococcal proteins that contain PDC/PAS domains regulate virulence factor synthesis or antibiotic resistance.

Nuclear localization of pyruvate dehydrogenase complex-E2 (PDC-E2), a mitochondrial enzyme, and its role in signal transducer and activator of transcription 5 (STAT5)-dependent gene transcription.

PubMed

Chueh, Fu-Yu; Leong, King-Fu; Cronk, Robert J; Venkitachalam, Srividya; Pabich, Samantha; Yu, Chao-Lan

2011-07-01

STAT (signal transducer and activator of transcription) proteins play a critical role in cellular response to a wide variety of cytokines and growth factors by regulating specific nuclear genes. STAT-dependent gene transcription can be finely tuned through the association with co-factors in the nucleus. We showed previously that STAT5 (including 5a and 5b) specifically interacts with a mitochondrial enzyme PDC-E2 (E2 subunit of pyruvate dehydrogenase complex) in both leukemic T cells and cytokine-stimulated cells. However, the functional significance of this novel association remains largely unknown. Here we report that PDC-E2 may function as a co-activator in STAT5-dependent nuclear gene expression. Subcellular fractionation analysis revealed that a substantial amount of PDC-E2 was constitutively present in the nucleus of BaF3, an interleukin-3 (IL-3)-dependent cell line. IL-3-induced tyrosine-phosphorylated STAT5 associated with nuclear PDC-E2 in co-immunoprecipitation analysis. These findings were confirmed by confocal immunofluorescence microscopy showing constant nuclear localization of PDC-E2 and its co-localization with STAT5 after IL-3 stimulation. Similar to mitochondrial PDC-E2, nuclear PDC-E2 was lipoylated and associated with PDC-E1. Overexpression of PDC-E2 in BaF3 cells augmented IL-3-induced STAT5 activity as measured by reporter assay with consensus STAT5-binding sites. Consistent with the reporter data, PDC-E2 overexpression in BaF3 cells led to elevated mRNA levels of endogenous SOCS3 (suppressor of cytokine signaling 3) gene, a known STAT5 target. We further identified two functional STAT5-binding sites in the SOCS3 gene promoter important for its IL-3-inducibility. The observation that both cis-acting elements were essential to detect the stimulatory effect by PDC-E2 strongly supports the role of PDC-E2 in up-regulating the transactivating ability of STAT5. All together, our results reveal a novel function of PDC-E2 in the nucleus. It also raises the possibility of nuclear-mitochondrial crosstalk through the interaction between STAT5 and PDC-E2. Copyright © 2011 Elsevier Inc. All rights reserved.

Nuclear localization of pyruvate dehydrogenase complex-E2 (PDC-E2), a mitochondrial enzyme, and its role in signal transducer and activator of transcription 5 (STAT5)-dependent gene transcription

PubMed Central

Chueh, Fu-Yu; Leong, King-Fu; Cronk, Robert J.; Venkitachalam, Srividya; Pabich, Samantha; Yu, Chao-Lan

2011-01-01

STAT (signal transducer and activator of transcription) proteins play a critical role in cellular response to a wide variety of cytokines and growth factors by regulating specific nuclear genes. STAT-dependent gene transcription can be finely tuned through the association with cofactors in the nucleus. We showed previously that STAT5 (including 5a and 5b) specifically interacts with a mitochondrial enzyme PDC-E2 (E2 subunit of pyruvate dehydrogenase complex) in both leukemic T cells and cytokine-stimulated cells. However, the functional significance of this novel association remains largely unknown. Here we report that PDC-E2 may function as a co-activator in STAT5-dependent nuclear gene expression. Subcellular fractionation analysis revealed that a substantial amount of PDC-E2 was constitutively present in the nucleus of BaF3, an interleukin-3 (IL-3)-dependent cell line. IL-3-induced tyrosine-phosphorylated STAT5 associated with nuclear PDC-E2 in co-immunoprecipitation analysis. These findings were confirmed by confocal immunofluorescence microscopy showing constant nuclear localization of PDC-E2 and its co-localization with STAT5 after IL-3 stimulation. Similar to mitochondrial PDC-E2, nuclear PDC-E2 was lipoylated and associated with PDC-E1. Overexpression of PDC-E2 in BaF3 cells augmented IL-3-induced STAT5 activity as measured by reporter assay with consensus STAT5-binding sites. Consistent with the reporter data, PDC-E2 overexpression in BaF3 cells led to elevated mRNA levels of endogenous SOCS3 (suppressor of cytokine signaling 3) gene, a known STAT5 target. We further identified two functional STAT5-binding sites in the SOCS3 gene promoter important for its IL-3-inducibility. The observation that both cis-acting elements were essential to detect the stimulatory effect by PDC-E2 strongly supports the role of PDC-E2 in up-regulating the transactivating ability of STAT5. All together, our results reveal a novel function of PDC-E2 in the nucleus. It also raises the possibility of nuclear-mitochondrial crosstalk through the interaction between STAT5 and PDC-E2. PMID:21397011

Therapeutic Targeting of the Pyruvate Dehydrogenase Complex/Pyruvate Dehydrogenase Kinase (PDC/PDK) Axis in Cancer.

PubMed

Stacpoole, Peter W

2017-11-01

The mitochondrial pyruvate dehydrogenase complex (PDC) irreversibly decarboxylates pyruvate to acetyl coenzyme A, thereby linking glycolysis to the tricarboxylic acid cycle and defining a critical step in cellular bioenergetics. Inhibition of PDC activity by pyruvate dehydrogenase kinase (PDK)-mediated phosphorylation has been associated with the pathobiology of many disorders of metabolic integration, including cancer. Consequently, the PDC/PDK axis has long been a therapeutic target. The most common underlying mechanism accounting for PDC inhibition in these conditions is post-transcriptional upregulation of one or more PDK isoforms, leading to phosphorylation of the E1α subunit of PDC. Such perturbations of the PDC/PDK axis induce a "glycolytic shift," whereby affected cells favor adenosine triphosphate production by glycolysis over mitochondrial oxidative phosphorylation and cellular proliferation over cellular quiescence. Dichloroacetate is the prototypic xenobiotic inhibitor of PDK, thereby maintaining PDC in its unphosphorylated, catalytically active form. However, recent interest in the therapeutic targeting of the PDC/PDK axis for the treatment of cancer has yielded a new generation of small molecule PDK inhibitors. Ongoing investigations of the central role of PDC in cellular energy metabolism and its regulation by pharmacological effectors of PDKs promise to open multiple exciting vistas into the biochemical understanding and treatment of cancer and other diseases. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Continuous depth profile of the rock strength in the Nankai accretionary prism based on drilling performance parameters.

PubMed

Hamada, Yohei; Kitamura, Manami; Yamada, Yasuhiro; Sanada, Yoshinori; Sugihara, Takamitsu; Saito, Saneatsu; Moe, Kyaw; Hirose, Takehiro

2018-02-14

A new method for evaluating the in situ rock strength beneath the seafloor is proposed and applied to the Nankai Trough accretionary prism. The depth-continuous in situ rock strength is a critical parameter for numerous studies in earth science, particularly for seismology and tectonics at plate convergence zones; yet, measurements are limited owing to a lack of drilled cores. Here, we propose a new indicator of strength, the equivalent strength (EST), which is determined only by drilling performance parameters such as drill string rotational torque, bit depth, and string rotational speed. A continuous depth profile of EST was drawn from 0 to 3000 m below the seafloor (mbsf) across the forearc basin and accretionary prism in the Nankai Trough. The EST did not show a significant increase around the forearc basin-accretionary prism boundary, but it did show a clear increase within the prism, ca. below 1500 mbsf. This result may indicate that even the shallow accretionary prism has been strengthened by horizontal compression derived from plate subduction. The EST is a potential parameter to continuously evaluate the in situ rock strength during drilling, and its accuracy of the absolute value can be improved by combining with laboratory drilling experiments.

Demonstration of PDC-E1 subunits as major antigens in the complement-fixing fraction M4 and re-evaluation of PDC-E1-specific antibodies in PBC patients.

PubMed

Berg, Christoph P; Stein, Gerburg M; Klein, Reinhild; Pascu, Maria; Berg, Thomas; Kammer, Winfried; Priemer, Martin; Nordheim, Alfred; Schulze-Osthoff, Klaus; Gregor, Michael; Wesselborg, Sebastian; Berg, Peter A

2006-09-01

Primary biliary cirrhosis (PBC) is characterized by the presence of antimitochondrial antibodies (AMA). Autoantibodies specific for the mitochondrial M4 antigen can be detected by a complement fixation test (CFT) but not by immunoblotting. The aim of this study was to elucidate the identity of the M4 antigen. M4 proteins were purified by affinity chromatography using IgG fractions of PBC marker sera being CFT positive (n=5) or negative (n=5) and identified by Western blotting, silver staining and sequence analysis. Further, a cohort of 57 PBC patients was tested for the reactivity to M4 and pyruvate dehydrogenase complex (PDC). Two AMA patterns of the marker sera were visualized: CFT-positive sera were defined as PDC-E2(+)/E1(+) and the CFT-negative sera as PDC-E2(+)/E1(-). The major proteins in the M4 fraction could be related to the PDC-E1 subunits. A clear-cut association between anti-M4 reactivity in the CFT and the reactivity to both PDC subunits could also be documented in the cohort of 57 PBC patients showing anti-PDC-E1alpha and E1beta antibodies at a frequency of 74% and 67%. CFT reactivity against M4 antigens could be preferentially identified as a reaction against PDC-E1. As PDC-E1 subunits as compared with PDC-E2 lack lipoyl-binding sites, they probably have to be considered as an independent and important target.

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

Tatur, I.R.; Prigul`skii, G.B.; Timokhin, I.A.

Enamel paints MS-17 and KhV-110 are used to protect drill bits during transportation and storage. But this requires the surface to be prepared carefully, which is often difficult under production conditions. Some of the promising anticorrosion agents are film-forming inhibited petroleum compounds (FIPC) - materials derived from high-temperature petroleum products blended with corrosion inhibitors and a solvent. Such compounds are used to protect unpainted and painted surfaces; this shortens the preservation process, and generally dispenses which depreservation. Further, they can be used to protect moist, wet, greasy, and rusted surfaces, and concealed inner areas where paint is difficult to apply.more » The purpose of this work was to obtain a film-forming inhibited petroleum compound that has high protective properties, can be applied on unprepared metal surfaces, and meets the following requirements: drill bit protection time during transportation and storage at least 24 months, coat adhesion to the metal at least of force 2, drop point > 90{degrees}C, the material must be applied by pneumatic spraying, in toxicity and inflammability the compound must be of class three, and coat drying time at 60{degrees}C not more than 12 min. The anticorrosion agents are described.« less

Optimal parameters to avoid thermal necrosis during bone drilling: A finite element analysis.

PubMed

Mediouni, Mohamed; Schlatterer, Daniel R; Khoury, Amal; Von Bergen, Tobias; Shetty, Sunil H; Arora, Manit; Dhond, Amit; Vaughan, Neil; Volosnikov, Alexander

2017-11-01

The drilling bone may potentially cause excessive frictional heat, which can lead to local bone necrosis. This heat generation and local necrosis has been suggested to contribute to the resorption of bone around the placed screws, ending in loss of screw purchase in the bone and inadvertent loosening and/or the bone-implant construct. In vivo studies on this subject have inherent obstacles not the least of which is controlling the variables and real time bone temperature data acquisition. Theoretical models can be generated using computer software and the inclusion of known constants for the mechanical properties of metal and bone. These known Data points for the variables (drill bit and bone) enables finite element analysis of various bone drilling scenarios. An elastic-plastic three-dimensional (3D) acetabular bone mode was developed and finite element model analysis (FEA) was applied to various simulated drilling procedures. The FEA results clearly indicate that the depth of drilling and the drill speed both have a significant effect on the temperature during drilling procedures. The reduction of the feeding speed leads to a reduction in bone temperature. Our data suggests that reducing the feeding speed regardless of RPMs and pressure applied could be a simple useful and effective way to reduce drilling temperatures. This study is the first step in helping any surgeon who drills bone and places screws to better understand the ideal pressure to apply and drill speed to employ and advance rate to avoid osteonecrosis. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2386-2391, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Stability analysis of coupled torsional vibration and pressure in oilwell drillstring system

NASA Astrophysics Data System (ADS)

Toumi, S.; Beji, L.; Mlayeh, R.; Abichou, A.

2018-01-01

To address security issues in oilwell drillstring system, the drilling operation handling which is in generally not autonomous but ensured by an operator may be drill bit destructive or fatal for the machine. To control of stick-slip phenomenon, the drillstring control at the right speed taking only the drillstring vibration is not sufficient as the mud dynamics and the pressure change around the drill pipes cannot be neglected. A coupled torsional vibration and pressure model is presented, and the well-posedness problem is addressed. As a Partial Differential Equation-Ordinary Differential Equation (PDE-ODE) coupled system, and in order to maintain a non destructive downhole pressure, we investigate the control stability with and without the damping term in the wave PDE. In terms of, the torsional variable, the downhole pressure, and the annulus pressure, the coupled system equilibrium is shown to be exponentially stable.

Development of improved high temperature seals and lubricants for downhole motors in geothermal applications

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

De La Fosse, P.H.; Black, A.D.; DiBona, B.G.

1983-01-01

A major limitation of downhole mud motors for geothermal drilling, as well as straight-hole oil and gas drilling, is the bearing section. Reduced bearing life results from the inability to seal a lubricant in the bearing pack. A reliable rotary seal will extend the bearing life and will allow high pressure drops across the bit for improved bottomhole cleaning and increased drilling rate. This paper summarizes the results of a six-year program funded by the U.S. Department of Energy/Division of Geothermal Energy to develop a sealed bearing pack for use with downhole motors in geothermal applications. Descriptions of the Sealmore » Test Machine, Lubricant Test Machine and Bearing Pack Test Facility are presented. Summaries of all seal tests, lubricant tests and bearing pack tests are provided; and a comprehensive program bibliography is presented.« less

PDC expressing CD36, CD61 and IL-10 may contribute to propagation of immune tolerance.

PubMed

Parcina, Marijo; Schiller, Martin; Gierschke, Aline; Heeg, Klaus; Bekeredjian-Ding, Isabelle

2009-05-01

Human plasmacytoid dendritic cells (PDC) are blood dendritic cell antigen 2 (BDCA2) and blood dendritic cell antigen 4 (BDCA4) positive leukocytes that do not express common lineage markers. They have been described as proinflammatory innate immune cells and are the major source of alphaIFN in the human body. PDC-derived secretion of type I IFNs upon triggering of nucleic acid-sensing toll-like receptors (TLR) primes immune cells to rapidly respond to microbial stimuli and promotes a Th1 response. Here, we report that human PDC express CD36 and CD61 (beta3 integrin), both involved in uptake of apoptotic cells and in induction of tolerance. Freshly isolated PDC and PDC within human blood leukocytes constitutively express IL-10. Thus, PDC may possess a so far neglected role in propagation of immune tolerance.

Applications of NTNU/SINTEF Drillability Indices in Hard Rock Tunneling

NASA Astrophysics Data System (ADS)

Zare, S.; Bruland, A.

2013-01-01

Drillability indices, i.e., the Drilling Rate Index™ (DRI), Bit Wear Index™ (BWI), Cutter Life Index™ (CLI), and Vickers Hardness Number Rock (VHNR), are indirect measures of rock drillability. These indices are recognized as providing practical characterization of rock properties used in the Norwegian University of Science and Technology (NTNU) time and cost prediction models available for hard rock tunneling and surface excavation. The tests form the foundation of various hard rock equipment capacity and performance prediction methods. In this paper, application of the tests for tunnel boring machine (TBM) and drill and blast (D&B) tunneling is investigated and the impact of the indices on excavation time and costs is presented.

Antimicrobial activity and mechanism of PDC213, an endogenous peptide from human milk

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

Sun, Yazhou; Nanjing Maternal and Child Health Medical Institute, Nanjing Maternal and Child Health Hospital, Obstetrics and Gynecology Hospital Affiliated to Nanjing Medical University, Nanjing; Zhou, Yahui

Human milk has always been considered an ideal source of elemental nutrients to both preterm and full term infants in order to optimally develop the infant's tissues and organs. Recently, hundreds of endogenous milk peptides were identified in human milk. These peptides exhibited angiotensin-converting enzyme inhibition, immunomodulation, or antimicrobial activity. Here, we report the antimicrobial activity and mechanism of a novel type of human antimicrobial peptide (AMP), termed PDC213 (peptide derived from β-Casein 213-226 aa). PDC213 is an endogenous peptide and is present at higher levels in preterm milk than in full term milk. The inhibitory concentration curve and diskmore » diffusion tests showed that PDC213 had obvious antimicrobial against S. aureus and Y. enterocolitica, the common nosocomial pathogens in neonatal intensive care units (NICUs). Fluorescent dye methods, electron microscopy experiments and DNA-binding activity assays further indicated that PDC213 can permeabilize bacterial membranes and cell walls rather than bind intracellular DNA to kill bacteria. Together, our results suggest that PDC213 is a novel type of AMP that warrants further investigation. - Highlights: • PDC213 is an endogenous peptide presenting higher levels in preterm milk. • PDC213 showed obvious antimicrobial against S. aereus and Y. enterocolitica. • PDC213 can permeabilize bacterial membranes and cell walls to kill bacterias. • PDC213 is a novel type of antimicrobial peptides worthy further investigation.« less

Top-down mass spectrometry reveals new sequence variants of the major bovine seminal plasma protein PDC-109.

PubMed

Laitaoja, Mikko; Sankhala, Rajeshwer S; Swamy, Musti J; Jänis, Janne

2012-07-01

The major protein of bovine seminal plasma, PDC-109, is a 109-residue polypeptide that exists as a polydisperse aggregate under native conditions. The oligomeric state of this aggregate varies with ionic strength and the presence of lipids. Binding of PDC-109 to choline phospholipids on the sperm plasma membrane results in an efflux of cholesterol and choline phospholipids, which is an important step in sperm capacitation. In this study, Fourier transform ion cyclotron resonance mass spectrometry was used to analyze PDC-109 purified from bovine seminal plasma. In addition to the previously known PDC-109 variants, four new sequence variants were identified by top-down mass spectrometry. For example, a protein variant containing point mutations P10L and G14R was identified along with another form having a 14-residue truncation in the N-terminal region. Two other minor variants could also be identified from the affinity-purified PDC-109. These results demonstrate that PDC-109 is naturally produced as a mixture of several protein forms, most of which have not been detected in previous studies. Native mass spectrometry revealed that PDC-109 is exclusively monomeric at low protein concentrations, suggesting that the protein oligomers are weakly bound and can easily be disrupted. Ligand binding to PDC-109 was also investigated, and it was observed that two molecules of O-phosphorylcholine bind to each PDC-109 monomer, consistent with previous reports. Copyright © 2012 John Wiley & Sons, Ltd.

Novel tannin-based Si, P co-doped carbon for supercapacitor applications

NASA Astrophysics Data System (ADS)

Ramasahayam, Sunil Kumar; Nasini, Udaya B.; Shaikh, Ali U.; Viswanathan, Tito

2015-02-01

Increasing environmental pollution and population compounded by a decrease in the availability of non-renewable resources and fossil fuels has propelled the need for sustainable alternate energy storage technologies particularly in the last two decades. An attempt to meet this crisis was carried out by a unique, microwave-assisted method which has enabled the generation of a novel Si, P co-doped carbon (SiPDC) for supercapacitor applications. The microwave-assisted method is useful in developing SiPDC at a rapid and economical fashion that does not employ any inert or reducing gases, but is high yielding. Varying proportions of precursor materials were utilized to generate four SiPDCs (SiPDC-1, SiPDC-2, SiPDC-3 and SiPDC-4) with varying contents of dopants as evidenced by X-ray photoelectron spectroscopic (XPS) results. Surface area and pore size analysis revealed that SiPDC-2 has a surface area of 641.51 m2 g-1, abundant micropores, mesopores and macropores which are critical for electrical double layer capacitance (EDLC). Of all the SiPDCs, SiPDC-2 exhibited highest capacitance of 276 F g-1 in 1 M H2SO4 and 244 F g-1 in 6 M KOH at a scan rate of 5 mV s-1. Galvanostatic charge-discharge studies performed in 6 M KOH establish the high capacitance of SiPDC-2. SiPDC-2 also exhibited excellent electrochemical stability in 1 M H2SO4 and 6 M KOH.

Optimizing Geothermal Drilling: Oil and Gas Technology Transfer

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

Denninger, Kate; Eustes, Alfred; Visser, Charles

There is a significant amount of financial risk associated with geothermal drilling. This study of drilling operations seeks opportunities to improve upon current practices and technologies. The scope of this study included analyzing 21 geothermal wells and 21 oil and gas wells. The goal was to determine a 'Perfect Well' using historical data to compare the best oil and gas well to the best geothermal well. Unfortunately, limitations encountered in the study included missing data (bit records, mud information, etc.) and poor data collection practices An online software database was used to format drilling data to IADC coded daily drillingmore » reports and generate figures for analysis. Six major issues have been found in geothermal drilling operations. These problems include lost circulation, rig/ equipment selection, cementing, penetration rate, drilling program, and time management. As a result of these issues, geothermal drilling averaged 56.4 days longer than drilling comparable oil and gas wells in the wells in this study. Roughly $13.9 million was spent on non-productive time in the 21 geothermal wells, compared with only $1.3 million in the oil and gas wells, assuming a cost of $50,000 per day. Comparable events such as drilling the same sized hole, tripping in/out, cementing, and running the same size casing took substantially less time in the oil and gas wells. Geothermal wells were drilled using older and/or less advanced technology to depths less than 10,000 feet, while oil and gas wells reached 12,500 feet faster with purpose built rigs. A new approach is now underway that will optimize drilling programs throughout the drilling industry using Mechanical Specific Energy (MSE) as a tool to realize efficient drilling processes. Potential improvements for current geothermal operations are: the use of electronic records, real time services, and official glossary terms to describe rig operations, and advanced drilling rigs/technology.« less

Type III IFNs are produced by and stimulate human plasmacytoid dendritic cells1

PubMed Central

Yin, Zhiwei; Dai, Jihong; Deng, Jing; Sheikh, Faruk; Natalia, Mahwish; Shih, Tiffany; Lewis-Antes, Anita; Amrute, Sheela B.; Garrigues, Ursula; Doyle, Sean; Donnelly, Raymond P; Kotenko, Sergei V; Fitzgerald-Bocarsly, Patricia

2012-01-01

Plasmacytoid dendritic cells (pDC) are rare cells found in peripheral blood and lymphoid tissues. pDC are considered to be “professional” type I interferon (IFN) producing cells and produce 10–100-fold more IFN-α than other cell types in response to enveloped viruses or synthetic TLR-7 and -9 agonists. In this study, purified pDC were found to express high levels of IFN-λ receptor mRNA as well as cell-surface IFN-λ receptor. We have developed intracellular flow cytometry assays using antibodies to IFN-λ1/3 or -λ2 to assess the expression of IFN-λ proteins by pDC. We observed that a subset of human pDC expresses only intracellular IFN-α while another subset produces both IFN-α and IFN-λ after stimulation with virus or the TLR9 agonist, CpGA; the cells that co-expressed IFN-α and IFN-λ were the cells with the highest levels of IFN-α expression. Antibody cross-linking of CD4 or BDCA-2 molecules on pDC inhibited both HSV-induced IFN-λ and IFN-α production. Like the production of IFN-α, the HSV-induced IFN-λ production in pDC was mediated through TLR9 and independent of virus replication. Exogenous IFN-λ treatment of pDC resulted in increased virus-induced expression of both IFN-α and IFN-λ. In addition, both exogenous IFN-λ and –α inhibited dexamethasone-induced apoptosis of pDC. We conclude that pDC are major producers of IFN-λ1 and –λ2 in response to viral stimulation and also express functional receptors for this cytokine. Thus, IFN-λ can serve as an autocrine signal to strengthen the antiviral response of pDC by increasing IFN-α and IFN-λ production, resulting in prolonged pDC survival. PMID:22891284

Paramagnetic nanoparticles to track and quantify in vivo immune human therapeutic cells

NASA Astrophysics Data System (ADS)

Aspord, Caroline; Laurin, David; Janier, Marc F.; Mandon, Céline A.; Thivolet, Charles; Villiers, Christian; Mowat, Pierre; Madec, Anne-Marie; Tillement, Olivier; Perriat, Pascal; Louis, Cédric; Bérard, Frédéric; Marche, Patrice N.; Plumas, Joël; Billotey, Claire

2013-11-01

This study aims to investigate gadolinium-based nanoparticles (Gd-HNP) for in vitro labeling of human plasmacytoid dendritic cells (HuPDC) to allow for in vivo tracking and HuPDC quantifying using magnetic resonance imaging (MRI) following parenteral injection. Human plasmacytoid DC were labeled (LabHuPDC) with fluorescent Gd-HNP (Gd-FITC-HNP) and injected via intraperitoneal and intravenous routes in 4-5 NOD-SCID β2m-/-mice (treated mice = TM). Control mice (CM) were similarly injected with unlabeled HuPDC. In vivo 7 T MRI was performed 24 h later and all spleens were removed in order to measure Gd and fluorescence contents and identify HuPDC. Gd-FITC-HNP efficiently labeled HuPDC (0.05 to 0.1 pg per cell), without altering viability and activation properties. The magnetic resonance (MR) signal was exclusively due to HuPDC. The normalized MR splenic intensity for TM was significantly higher than for CM (p < 0.024), and highly correlated with the spleen Gd content (r = 0.97), and the number of HuPDC found in the spleen (r = 0.94). Gd-FITC-HNP allowed for in vivo tracking and HuPDC quantifying by means of MRI following parenteral injection, with very high sensitivity (<3000 cells per mm3). The safety of these new nanoparticle types must be confirmed via extensive toxicology tests including in vivo stability and biodistribution studies.This study aims to investigate gadolinium-based nanoparticles (Gd-HNP) for in vitro labeling of human plasmacytoid dendritic cells (HuPDC) to allow for in vivo tracking and HuPDC quantifying using magnetic resonance imaging (MRI) following parenteral injection. Human plasmacytoid DC were labeled (LabHuPDC) with fluorescent Gd-HNP (Gd-FITC-HNP) and injected via intraperitoneal and intravenous routes in 4-5 NOD-SCID β2m-/-mice (treated mice = TM). Control mice (CM) were similarly injected with unlabeled HuPDC. In vivo 7 T MRI was performed 24 h later and all spleens were removed in order to measure Gd and fluorescence contents and identify HuPDC. Gd-FITC-HNP efficiently labeled HuPDC (0.05 to 0.1 pg per cell), without altering viability and activation properties. The magnetic resonance (MR) signal was exclusively due to HuPDC. The normalized MR splenic intensity for TM was significantly higher than for CM (p < 0.024), and highly correlated with the spleen Gd content (r = 0.97), and the number of HuPDC found in the spleen (r = 0.94). Gd-FITC-HNP allowed for in vivo tracking and HuPDC quantifying by means of MRI following parenteral injection, with very high sensitivity (<3000 cells per mm3). The safety of these new nanoparticle types must be confirmed via extensive toxicology tests including in vivo stability and biodistribution studies. Corresponding address: Service de Médecine Nucléaire, Hôpital, Nord - CHU Saint-Etienne, Avenue Albert Raimond, 42270 Saint-Priest-en-Jarez, France. E-mail: claire.billotey@chu-st-etienne.fr

Osteosynthesis for clavicle fractures: How close are we to penetration of neurovascular structures?

PubMed

Stillwell, A; Ioannou, C; Daniele, L; Tan, S L E

2017-02-01

Risks associated with drill plunging are well recognised in clavicle osteosynthesis. To date no studies have described plunge depth associated with clavicle osteosynthesis. To determine whether plunge depth associated with clavicle osteosynthesis is great enough to penetrate neurovascular structures and whether surgical experience reduces the risk of neurovascular injury METHOD: Cadaveric clavicles were pressed into spongy phenolic foam to allow measurement of drill bit penetration beyond the far cortex (plunge depth). 15 surgeons grouped according to experience were asked to drill a single hole in the medial, middle and lateral clavicle in 2 specimens each. Each surgeon used fully a charged standard Stryker drill with a new 2.6mm drill bit and guide. Plunge depths were measured in 0.5mm increments. Depth measurements were compared amongst groups and to previously documented distances to neurovascular structures as outlined by Robinson et al. Kruskal-Wallis test was used for overall comparison and Mann-Whitney U test was used for comparing the groups individually. Mean plunge depth across all groups was 3.4mm, (0.5-6.5), 4.0mm (1mm-8.5mm) and 4.0mm (0.5mm-15mm) in the medial, middle and lateral clavicle. Plunge depths were greater than previously documented distances to the subclavian vein at the medial clavicle on nine occasions. Plunge depths in the middle and lateral clavicle were well within the previously documented distances from neurovascular structures. There was no correlation between level of experience and median plunge depth (p=0.18). However, inexperienced surgeons plunged 1mm greater than intermediate and experienced surgeons (p=0.026). There was one significant outlier; a 15mm plunge depth by an inexperienced surgeon in the lateral clavicle. Clavicle osteosynthesis has a relatively high risk of neurovascular injury. Plunge depths through the clavicle often exceed the distance of neurovascular structures, especially in the medial clavicle. A thorough understanding of the anatomy of these neurovascular structures and methods to prevent excessive plunging is important prior to undertaking clavicle osteosynthesis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Resonance: The science behind the art of sonic drilling

NASA Astrophysics Data System (ADS)

Lucon, Peter Andrew

The research presented in this dissertation quantifies the system dynamics and the influence of control variables of a sonic drill system. The investigation began with an initial body of work funded by the Department of Energy under a Small Business Innovative Research Phase I Grant, grant number: DE-FG02-06ER84618, to investigate the feasibility of using sonic drills to drill micro well holes to depths of 1500 feet. The Department of Energy funding enabled feasibility testing using a 750 hp sonic drill owned by Jeffery Barrow, owner of Water Development Co. During the initial feasibility testing, data was measured and recorded at the sonic drill head while the sonic drill penetrated to a depth of 120 feet. To demonstrate feasibility, the system had to be well understood to show that testing of a larger sonic drill could simulate the results of drilling a micro well hole of 2.5 inch diameter. A first-order model of the system was developed that produced counter-intuitive findings that enabled the feasibility of using this method to drill deeper and produce micro-well holes to 1500 feet using sonic drills. Although funding was not continued, the project work continued. This continued work expanded on the sonic drill models by understanding the governing differential equation and solving the boundary value problem, finite difference methods, and finite element methods to determine the significance of the control variables that can affect the sonic drill. Using a design of experiment approach and commercially available software, the significance of the variables to the effectiveness of the drill system were determined. From the significant variables, as well as the real world testing, a control system schematic for a sonic drill was derived and is patent pending. The control system includes sensors, actuators, personal logic controllers, as well as a human machine interface. It was determined that the control system should control the resonant mode and the weight on the bit as the primary two control variables. The sonic drill can also be controlled using feedback from sensors mounted on the sonic drill head, which is the driver for the sonic drill located above ground

Computational modeling of the nonlinear stochastic dynamics of horizontal drillstrings

NASA Astrophysics Data System (ADS)

Cunha, Americo; Soize, Christian; Sampaio, Rubens

2015-11-01

This work intends to analyze the nonlinear stochastic dynamics of drillstrings in horizontal configuration. For this purpose, it considers a beam theory, with effects of rotatory inertia and shear deformation, which is capable of reproducing the large displacements that the beam undergoes. The friction and shock effects, due to beam/borehole wall transversal impacts, as well as the force and torque induced by bit-rock interaction, are also considered in the model. Uncertainties of bit-rock interaction model are taken into account using a parametric probabilistic approach. Numerical simulations have shown that the mechanical system of interest has a very rich nonlinear stochastic dynamics, which generate phenomena such as bit-bounce, stick-slip, and transverse impacts. A study aiming to maximize the drilling process efficiency, varying drillstring velocities of translation and rotation is presented. Also, the work presents the definition and solution of two optimizations problems, one deterministic and one robust, where the objective is to maximize drillstring rate of penetration into the soil respecting its structural limits.

Correlation of membrane binding and hydrophobicity to the chaperone-like activity of PDC-109, the major protein of bovine seminal plasma.

PubMed

Sankhala, Rajeshwer S; Damai, Rajani S; Swamy, Musti J

2011-03-08

The major protein of bovine seminal plasma, PDC-109 binds to choline phospholipids present on the sperm plasma membrane upon ejaculation and plays a crucial role in the subsequent events leading to fertilization. PDC-109 also shares significant similarities with small heat shock proteins and exhibits chaperone-like activity (CLA). Although the polydisperse nature of this protein has been shown to be important for its CLA, knowledge of other factors responsible for such an activity is scarce. Since surface exposure of hydrophobic residues is known to be an important factor which modulates the CLA of chaperone proteins, in the present study we have probed the surface hydrophobicity of PDC-109 using bisANS and ANS. Further, effect of phospholipids on the structure and chaperone-like activity of PDC-109 was studied. Presence of DMPC was found to increase the CLA of PDC-109 significantly, which could be due to the considerable exposure of hydrophobic regions on the lipid-protein recombinants, which can interact productively with the nonnative structures of target proteins, resulting in their protection. However, inclusion of DMPG instead of DMPC did not significantly alter the CLA of PDC-109, which could be due to the lower specificity of PDC-109 for DMPG as compared to DMPC. Cholesterol incorporation into DMPC membranes led to a decrease in the CLA of PDC-109-lipid recombinants, which could be attributed to reduced accessibility of hydrophobic surfaces to the substrate protein(s). These results underscore the relevance of phospholipid binding and hydrophobicity to the chaperone-like activity of PDC-109.

The lipid composition modulates the influence of the bovine seminal plasma protein PDC-109 on membrane stability.

PubMed

Tannert, Astrid; Töpfer-Petersen, Edda; Herrmann, Andreas; Müller, Karin; Müller, Peter

2007-10-16

The bovine seminal plasma protein PDC-109 exerts an essential influence on the sperm cell plasma membrane during capacitation. However, by any mechanism, it has to be ensured that this function of the protein on sperm cells is not initiated too early, that is, upon ejaculation when PDC-109 and sperm cells come into first contact, but rather at later stages of sperm genesis in the female genital tract. To answer the question of whether changes of the bovine sperm lipid composition can modulate the effect of PDC-109 on sperm membranes, we have investigated the influence of PDC-109 on the integrity of (i) differently composed lipid vesicles and of (ii) membranes from human red blood cells and bovine spermatozoa. PDC-109 most effectively disturbed lipid membranes composed of choline-containing phospholipids and in the absence of cholesterol. The impact of the protein on lipid vesicles was attenuated in the presence of cholesterol or of noncholine-containing phospholipids, such as phosphatidylethanolamine or phosphatidylserine. An extraction of cholesterol from lipid or biological membranes using methyl-beta-cyclodextrin caused an increased membrane perturbation by PDC-109. Our results argue for a oppositional effect of PDC-109 during sperm cell genesis. We hypothesize that the lipid composition of ejaculated bull sperm cells allows a binding of PDC-109 without leading to an impairment of the plasma membrane. At later stages of sperm cell genesis upon release of cholesterol from sperm membranes, PDC-109 triggers a destabilization of the cells.

The role of FOXO and PPAR transcription factors in diet-mediated inhibition of PDC activation and carbohydrate oxidation during exercise in humans and the role of pharmacological activation of PDC in overriding these changes.

PubMed

Constantin-Teodosiu, Dumitru; Constantin, Despina; Stephens, Francis; Laithwaite, David; Greenhaff, Paul L

2012-05-01

High-fat feeding inhibits pyruvate dehydrogenase complex (PDC)-controlled carbohydrate (CHO) oxidation, which contributes to muscle insulin resistance. We aimed to reveal molecular changes underpinning this process in resting and exercising humans. We also tested whether pharmacological activation of PDC overrides these diet-induced changes. Healthy males consumed a control diet (CD) and on two further occasions an isocaloric high-fat diet (HFD). After each diet, subjects cycled for 60 min after intravenous infusion with saline (CD and HFD) or dichloroacetate (HFD+DCA). Quadriceps muscle biopsies obtained before and after 10 and 60 min of exercise were used to estimate CHO use, PDC activation, and mRNAs associated with insulin, fat, and CHO signaling. Compared with CD, HFD increased resting pyruvate dehydrogenase kinase 2 (PDK2), PDK4, forkhead box class O transcription factor 1 (FOXO1), and peroxisome proliferator-activated receptor transcription factor α (PPARα) mRNA and reduced PDC activation. Exercise increased PDC activation and whole-body CHO use in HFD, but to a lower extent than in CD. Meanwhile PDK4 and FOXO1, but not PPARα or PDK2, mRNA remained elevated. HFD+DCA activated PDC throughout and restored whole-body CHO use during exercise. FOXO1 appears to play a role in HFD-mediated muscle PDK4 upregulation and inhibition of PDC and CHO oxidation in humans. Also, pharmacological activation of PDC restores HFD-mediated inhibition of CHO oxidation during exercise.

Decreased frequency and function of circulating plasmocytoid dendritic cells (pDC) in hepatitis B virus infected humans.

PubMed

Duan, Xue-Zhang; Wang, Min; Li, Han-Wei; Zhuang, Hui; Xu, Dongping; Wang, Fu-Sheng

2004-11-01

The Type 2 precursor plasmacytoid dendritic cells (pDC) represent the most important cell type in antiviral innate immunity. To understand the function of pDC during hepatitis B virus infection, the frequency and function of circulating pDC were analyzed by flow cytometric analysis, and IFN-alpha secretion of total PBMCs was determined by ELISA assay in 25 healthy subjects and 116 patients at various stages of chronic hepatitis B virus infection (CHB). The number of circulating pDC was found to be significantly lower in patients with CHB and associated liver cirrhosis (LC). The ability of PBMCs to secrete IFN-alpha also decreased significantly. There was a corresponding decrease of circulating NK cells and CD8+ T cells. We observed that lamuvidine antiviral therapy restored the number of circulating pDC and there was a reversal of pDC frequency with the control of HBV replication in chronic HBV patients, indicating these subjects are unlikely to be totally immunocompromised. The decrease of pDC was found to be related to nosocomial infections in LC patients. Our results suggest that CHB patients probably have a quantitative and qualitative impairment of circulating pDC or NK cells, which may be associated with HBV persistent infection as well as the nosocomial infections that arise in LC patients.

Identification of PDC-109-like protein(s) in buffalo seminal plasma.

PubMed

Harshan, Hiron M; Sankar, Surya; Singh, L P; Singh, Manish Kumar; Sudharani, S; Ansari, M R; Singh, S K; Majumdar, A C; Joshi, P

2009-10-01

The FN-2 family of seminal plasma proteins represents the major protein fraction of bovine seminal plasma. These proteins also constitute the major seminal plasma proteins fraction in horse, goat and bison seminal plasma and are present in pig, rat, mouse, hamster and human seminal plasma. BSP-A1 and BSP-A2, the predominant proteins of the FN-2 family, are collectively termed as PDC-109. Fn-2 proteins play an important role in fertilization, including sperm capacitation and formation of oviductal sperm reservoirs. Significantly, BSP proteins were also shown to have negative effects in the context of sperm storage. No conclusive evidence for the presence of buffalo seminal plasma protein(s) similar to PDC-109 exists. Studies with buffalo seminal plasma indicated that isolation and identification of PDC-109-like protein(s) from buffalo seminal plasma by conventional methods might be difficult. Thus, antibodies raised against PDC-109 isolated, and purified from cattle seminal plasma, were used for investigating the presence of PDC-109-like protein(s) in buffalo seminal plasma. Buffalo seminal plasma proteins were resolved on SDS-PAGE, blotted to nitro cellulose membranes and probed for the presence of PDC-109-like protein(s) using the PDC-109 antisera raised in rabbits. A distinct immunoreactive band well below the 20-kDa regions indicated the presence of PDC-109-like protein(s) in buffalo seminal plasma.

Relationship between the maxillary transverse dimension and palatally displaced canines: A cone-beam computed tomographic study.

PubMed

Hong, Wei-Hsin; Radfar, Rebecca; Chung, Chun-Hsi

2015-05-01

To examine the relationship between palatally displaced maxillary canines (PDC) and the maxillary transverse dimension using cone-beam computed tomography (CBCT). Thirty-three patients (11 males and 22 females, mean age 18.2 years) with PDC were matched to 66 patients (22 males and 44 females, mean age 18.1 years) without PDC (control) by gender, age, and posterior occlusion. A CBCT image was taken on all the patients prior to any orthodontic treatment. For each patient the maxillary basal bone widths and interdental widths at the maxillary first molars and first and second premolars were measured on axial and coronal sections of CBCT images. In addition, the presence of permanent tooth agenesis and the widths of maxillary incisors were recorded. Similar maxillary transverse dimensions, both skeletally and dentally, were found between the PDC and control groups. In the PDC group, the number of patients with permanent tooth agenesis was six times higher than in the control group. In addition, the maxillary lateral incisors on PDC-affected sides were smaller than those of control group (P < .05). The maxillary transverse dimension, both skeletally and dentally, had no effect on the occurrence of PDC. The higher prevalence of permanent tooth agenesis was found in the PDC group. Moreover, the mean mesiodistal width of maxillary lateral incisors in the PDC group was significantly smaller than in the control group (P < .05).

The bovine seminal plasma protein PDC-109 extracts phosphorylcholine-containing lipids from the outer membrane leaflet.

PubMed

Tannert, Astrid; Kurz, Anke; Erlemann, Karl-Rudolf; Müller, Karin; Herrmann, Andreas; Schiller, Jürgen; Töpfer-Petersen, Edda; Manjunath, Puttaswamy; Müller, Peter

2007-04-01

The bovine seminal plasma protein PDC-109 modulates the maturation of bull sperm cells by removing lipids, mainly phosphatidylcholine and cholesterol, from their cellular membrane. Here, we have characterized the process of extraction of endogenous phospholipids and of their respective analogues. By measuring the PDC-109-mediated release of fluorescent phospholipid analogues from lipid vesicles and from biological membranes (human erythrocytes, bovine epididymal sperm cells), we showed that PDC-109 extracts phospholipids with a phosphorylcholine headgroup mainly from the outer leaflet of these membranes. The ability of PDC-109 to extract endogenous phospholipids from epididymal sperm cells was followed by mass spectrometry, which allowed us to characterize the fatty acid pattern of the released lipids. From these cells, PDC-109 extracted phosphatidylcholine and sphingomyelin that contained an enrichment of mono- and di-unsaturated fatty acids as well as short-chain and lyso-phosphatidylcholine species. Based on the results, a model explaining the phospholipid specificity of PDC-109-mediated lipid release is presented.

Future Directions of Electromagnetic Methods for Hydrocarbon Applications

NASA Astrophysics Data System (ADS)

Strack, K. M.

2014-01-01

For hydrocarbon applications, seismic exploration is the workhorse of the industry. Only in the borehole, electromagnetic (EM) methods play a dominant role, as they are mostly used to determine oil reserves and to distinguish water from oil-bearing zones. Throughout the past 60 years, we had several periods with an increased interest in EM. This increased with the success of the marine EM industry and now electromagnetics in general is considered for many new applications. The classic electromagnetic methods are borehole, onshore and offshore, and airborne EM methods. Airborne is covered elsewhere (see Smith, this issue). Marine EM material is readily available from the service company Web sites, and here I will only mention some future technical directions that are visible. The marine EM success is being carried back to the onshore market, fueled by geothermal and unconventional hydrocarbon applications. Oil companies are listening to pro-EM arguments, but still are hesitant to go through the learning exercises as early adopters. In particular, the huge business drivers of shale hydrocarbons and reservoir monitoring will bring markets many times bigger than the entire marine EM market. Additional applications include support for seismic operations, sub-salt, and sub-basalt, all areas where seismic exploration is costly and inefficient. Integration with EM will allow novel seismic methods to be applied. In the borehole, anisotropy measurements, now possible, form the missing link between surface measurements and ground truth. Three-dimensional (3D) induction measurements are readily available from several logging contractors. The trend to logging-while-drilling measurements will continue with many more EM technologies, and the effort of controlling the drill bit while drilling including look-ahead-and-around the drill bit is going on. Overall, the market for electromagnetics is increasing, and a demand for EM capable professionals will continue. The emphasis will be more on application and data integration (bottom-line value increase) and less on EM technology and modeling exercises.

Plasmacytoid pre-dendritic cells (pDC): from molecular pathways to function and disease association.

PubMed

Alculumbre, Solana; Raieli, Salvatore; Hoffmann, Caroline; Chelbi, Rabie; Danlos, François-Xavier; Soumelis, Vassili

2018-02-19

Plasmacytoid pre-dendritic cells (pDC) are a specialized DC population with a great potential to produce large amounts of type I interferon (IFN). pDC are involved in the initiation of antiviral immune responses through their interaction with innate and adaptive immune cell populations. In a context-dependent manner, pDC activation can induce their differentiation into mature DC able to induce both T cell activation or tolerance. In this review, we described pDC functions during immune responses and their implication in the clearance or pathogenicity of human diseases during infection, autoimmunity, allergy and cancer. We discuss recent advances in the field of pDC biology and their implication for future studies. Copyright © 2018 Elsevier Ltd. All rights reserved.

Snare coupling of the pre-pectoral pacing lead delivery catheter to the femoral transseptal apparatus for endocardial cardiac resynchronization therapy : mid-term results.

PubMed

Patel, Mehul B; Worley, Seth J

2013-04-01

Limitations imposed by the coronary sinus venous anatomy triggered the transseptal approach for endocardial LV lead placement. The alignment of the interatrial septum (IAS) and its neighborhood anatomy does not favor transseptal puncture from the pre-pectoral area. Locating and advancing a pre-pectoral LV lead delivery catheter (PDC) through an opening created in the IAS via femoral transseptal puncture (FTP) is time consuming and technically difficult. We describe a method where the PDC is snare coupled to the femoral transseptal apparatus (FTA). When the FTA is advanced into the left atrium (LA) the coupled PDC follows. The catheter of a 25-mm loop snare kit is replaced with the PDC (SelectSite®). The snare loop is positioned in the right common iliac vein from the pre-pectoral access. The PDC is coupled to the FTA by advancing the transseptal apparatus through the open snare loop. After conventional FTP, the FTA is withdrawn back into the right atrium (RA) over an extra support wire positioned in the LA. The PDC with open snare loop is pulled over the FTA up to the RA. The PDC is advanced to close the snare loop on the extra support wire immediately distal to the tip of the dilator close to the puncture site. The PDC is deflected to align with the FTA. The snare coupled catheters are gently advanced across the IAS into the LA. The PDC is released from the FTA by advancing the snare and opening the loop; the snare is then removed from the PDC. The PDC is deflected and advanced into the left ventricle (LV). After positioning the 4.1 Fr lumen less LV lead, the PDC is sliced and removed. The PDC snare coupled to the FTA was advanced into the LA in all five patients, however, access was lost during catheter manipulation in the one right-sided case. Endocardial LV lead was successfully positioned in all five patients. Snare coupling the pre-pectoral SelectSite® catheter to the FTA is technically simple, reliable and a safe method for transseptal endocardial LV lead placement for left pre-pectoral implantation.

DNA Hairpins Containing the Cytidine Analog Pyrrolo-dC: Structural, Thermodynamic, and Spectroscopic Studies

PubMed Central

Zhang, Xu; Wadkins, Randy M.

2009-01-01

Structures formed by single-strand DNA have become increasingly interesting because of their roles in a number of biological processes, particularly transcription and its regulation. Of particular importance is the fact that antitumor drugs such as Actinomycin D can selectively bind DNA hairpins over fully paired, double-strand DNA. A new fluorescent base analog, pyrrolo-deoxycytidine (PdC), can now be routinely incorporated into single-strand DNA. The fluorescence of PdC is particularly useful for studying the formation of single-strand DNA in regions of double-strand DNA. The fluorescence is quenched when PdC is paired with a complementary guanine residue, and thus is greatly enhanced upon formation of single-strand DNA. Hence, any process that results in melting or opening of DNA strands produces an increase in the fluorescence intensity of this base analog. In this study we measured the structural effects of incorporating PdC into DNA hairpins, and the effect of this incorporation on the binding of the hairpins by a fluorescent analog of the drug Actinomycin D. Two hairpin DNAs were used: one with PdC in the stem (basepaired) and one with PdC in the loop (unpaired). The thermal stability, 7-aminoactinomycin D binding, and three-dimensional structures of PdC incorporated into these DNA hairpins were all quite similar as compared to the hairpins containing an unmodified dC residue. Fluorescence lifetime measurements indicate that two lifetimes are present in PdC, and that the increase in fluorescence of the unpaired PdC residue compared to the basepaired PdC is due to an increase in the contribution of the longer lifetime to the average fluorescence lifetime. Our data indicate that PdC can be used effectively to differentiate paired and unpaired bases in DNA hairpin secondary structures, and should be similarly applicable for related structures such as cruciforms and quadruplexes. Further, our data indicate that PdC can act as a fluorescence resonance energy transfer donor for the fluorescent drug 7-aminoactinomycin D. PMID:19254547

DNA hairpins containing the cytidine analog pyrrolo-dC: structural, thermodynamic, and spectroscopic studies.

PubMed

Zhang, Xu; Wadkins, Randy M

2009-03-04

Structures formed by single-strand DNA have become increasingly interesting because of their roles in a number of biological processes, particularly transcription and its regulation. Of particular importance is the fact that antitumor drugs such as Actinomycin D can selectively bind DNA hairpins over fully paired, double-strand DNA. A new fluorescent base analog, pyrrolo-deoxycytidine (PdC), can now be routinely incorporated into single-strand DNA. The fluorescence of PdC is particularly useful for studying the formation of single-strand DNA in regions of double-strand DNA. The fluorescence is quenched when PdC is paired with a complementary guanine residue, and thus is greatly enhanced upon formation of single-strand DNA. Hence, any process that results in melting or opening of DNA strands produces an increase in the fluorescence intensity of this base analog. In this study we measured the structural effects of incorporating PdC into DNA hairpins, and the effect of this incorporation on the binding of the hairpins by a fluorescent analog of the drug Actinomycin D. Two hairpin DNAs were used: one with PdC in the stem (basepaired) and one with PdC in the loop (unpaired). The thermal stability, 7-aminoactinomycin D binding, and three-dimensional structures of PdC incorporated into these DNA hairpins were all quite similar as compared to the hairpins containing an unmodified dC residue. Fluorescence lifetime measurements indicate that two lifetimes are present in PdC, and that the increase in fluorescence of the unpaired PdC residue compared to the basepaired PdC is due to an increase in the contribution of the longer lifetime to the average fluorescence lifetime. Our data indicate that PdC can be used effectively to differentiate paired and unpaired bases in DNA hairpin secondary structures, and should be similarly applicable for related structures such as cruciforms and quadruplexes. Further, our data indicate that PdC can act as a fluorescence resonance energy transfer donor for the fluorescent drug 7-aminoactinomycin D.

Theoretical analysis of multiphase flow during oil-well drilling by a conservative model

NASA Astrophysics Data System (ADS)

Nicolas-Lopez, Ruben

2005-11-01

In order to decrease cost and improve drilling operations is necessary a better understood of the flow mechanisms. Therefore, it was carried out a multiphase conservative model that includes three mass equations and a momentum equation. Also, the measured geothermal gradient is utilized by state equations for estimating physical properties of the phases flowing. The mathematical model is solved by numerical conservative schemes. It is used to analyze the interaction among solid-liquid-gas phases. The circulating system consists as follow, the circulating fluid is pumped downward into the drilling pipe until the bottom of the open hole then it flows through the drill bit, and at this point formation cuttings are incorporated to the circulating fluid and carried upward to the surface. The mixture returns up to the surface by an annular flow area. The real operational conditions are fed to conservative model and the results are matched up to field measurements in several oil wells. Mainly, flow rates, drilling rate, well and tool geometries are data to estimate the profiles of pressure, mixture density, equivalent circulating density, gas fraction and solid carrying capacity. Even though the problem is very complex, the model describes, properly, the hydrodynamics of drilling techniques applied at oil fields. *Authors want to thank to Instituto Mexicano del Petroleo and Petroleos Mexicanos for supporting this research.

Unrecoverable bi-products of drilling titanium alloy and tantalum metal implants: a pilot study.

PubMed

Skowronek, Paweł; Olszewski, Paweł; Święszkowski, Wojciech; Synder, Marek; Sibiński, Marcin; Mazek, Jacek

2018-05-01

Trabecular metal implants with a porous architecture that allows for the incorporation of bone into the implant during healing are gaining popularity in alloplastic revision procedures. The bi-products of drilling titanium alloy (Ti) and tantalum (Ta) implants have not been previously assessed. Four holes were drilled in each of two spatially porous trabecular implants, one Ta and the other Ti alloy (Ti-6Al-7Nb), for this pilot in vitro study. The particles were flushed out with a continuous flow of saline. The particles' weight and the volume were then measured using a Radwag XA 110/2X (USA) laboratory balance. The total volume of the obtained metal fines was measured by titration using a 10 mm 3 measurement system. A cobalt carbide bit was used since the holes could not be made with a standard bone drill. Each Ti and Ta implant lost 1.26 g and 2.48 g of mass, respectively. The volume of free particles recovered after each stage was 280 mm 3 and 149 mm 3 , respectively. Approximately 0.6% of the total implant mass was not recovered after drilling (roughly 2% of the mass of the particles created by drilling), despite the use of 5 µm filters. It is technically difficult to drill holes in Ti and Ta implants using standard surgical tools. The drilling process creates a considerable amount of metal particles, which cannot be recovered despite intensive flushing. This may have an adverse influence on the bio-functionality (survival) of the endoprosthesis and present deleterious systemic consequences.

Pyruvate dehydrogenase complex (PDC) subunits moonlight as interaction partners of phosphorylated STAT5 in adipocytes and adipose tissue.

PubMed

Richard, Allison J; Hang, Hardy; Stephens, Jacqueline M

2017-12-01

STAT5 proteins play a role in adipocyte development and function, but their specific functions are largely unknown. To this end, we used an unbiased MS-based approach to identify novel STAT5-interacting proteins. We observed that STAT5A bound the E1β and E2 subunits of the pyruvate dehydrogenase complex (PDC). Whereas STAT5A typically localizes to the cytosol or nucleus, PDC normally resides within the mitochondrial matrix where it converts pyruvate to acetyl-CoA. We employed affinity purification and immunoblotting to validate the interaction between STAT5A and PDC subunits in murine and human cultured adipocytes, as well as in adipose tissue. We found that multiple PDC subunits interact with hormone-activated STAT5A in a dose- and time-dependent manner that coincides with tyrosine phosphorylation of STAT5. Using subcellular fractionation and immunofluorescence microscopy, we observed that PDC-E2 is present within the adipocyte nucleus where it associates with STAT5A. Because STAT5A is a transcription factor, we used chromatin immunoprecipitation (ChIP) to assess PDC's ability to interact with STAT5 DNA-binding sites. These analyses revealed that PDC-E2 is bound to a STAT5-binding site in the promoter of the STAT5 target gene c ytokine- i nducible SH 2-containing protein ( cish ). We have demonstrated a compelling interaction between STAT5A and PDC subunits in adipocytes under physiological conditions. There is previous evidence that PDC localizes to cancer cell nuclei where it plays a role in histone acetylation. On the basis of our ChIP data and these previous findings, we hypothesize that PDC may modulate STAT5's ability to regulate gene expression by controlling histone or STAT5 acetylation. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Optimizing Geothermal Drilling: Oil and Gas Technology Transfer

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

Tilley, Mitch; Eustes, Alfred; Visser, Charles

There is a significant amount of financial risk associated with geothermal drilling; however, there are opportunities to improve upon current practices and technologies used. The scope of this drilling operational study included 21 geothermal wells and 21 oil and gas wells. The goal was to determine a 'perfect well' using historical data to compare the best oil and gas well to the best geothermal well. Unfortunately, limitations encountered in the study included missing data (bit records, mud information, etc.), poor data collection, and difficult to ascertain handwriting. An online software database was used to format drilling data to IADC codedmore » daily drilling reports and generate analysis figures. Six major issues have been found in geothermal drilling operations. These problems include lost circulation, rig/equipment selection, cementing, penetration rate, drilling program, and time management. As a result of these issues, geothermal drilling averages 56.4 days longer than drilling comparable oil and gas wells in the wells in this study. Roughly $13.9 million would be lost due to non-productive time in the 21 geothermal wells and only $1.3 million in the oil and gas wells, assuming a cost of $50,000 per day. Comparable events such as drilling the same sized hole, tripping in/out, cementing, and running the same size casing took substantially less time in the oil and gas wells. Geothermal wells were drilled using older and/or less advanced technology to depths less than 10,000 feet, while oil and gas wells reached 12,500 feet faster with purpose built rigs. A new approach is now underway that will optimize drilling programs throughout the drilling industry. It is the use of Mechanical Specific Energy (MSE) as a tool to realize efficient drilling processes. However, a work-flow must also be established in order for there to be an efficient drilling program. Potential improvements for current geothermal operations are: the use of electronic records, real time services, and official glossary terms to describe rig operations, and advanced drilling rigs/technology.« less

Expression of the CTLA-4 ligand CD86 on plasmacytoid dendritic cells (pDC) predicts risk of disease recurrence after treatment discontinuation in CML.

PubMed

Schütz, C; Inselmann, S; Sausslele, S; Dietz, C T; Mu Ller, M C; Eigendorff, E; Brendel, C A; Metzelder, S K; Bru Mmendorf, T H; Waller, C; Dengler, J; Goebeler, M E; Herbst, R; Freunek, G; Hanzel, S; Illmer, T; Wang, Y; Lange, T; Finkernagel, F; Hehlmann, R; Huber, M; Neubauer, A; Hochhaus, A; Guilhot, J; Xavier Mahon, F; Pfirrmann, M; Burchert, A

2017-04-01

It is unknown, why only a minority of chronic myeloid leukemia (CML) patients sustains treatment free remission (TFR) after discontinuation of tyrosine kinase inhibitor (TKI) therapy in deep molecular remission (MR). Here we studied, whether expression of the T-cell inhibitory receptor (CTLA-4)-ligand CD86 (B7.2) on plasmacytoid dendritic cells (pDC) affects relapse risk after TKI cessation. CML patients in MR displayed significantly higher CD86 + pDC frequencies than normal donors (P<0.0024), whereas TFR patients had consistently low CD86 + pDC (n=12). This suggested that low CD86 + pDC might be predictive of TFR. Indeed, in a prospective analysis of 122 patients discontinuing their TKI within the EURO-SKI trial, the one-year relapse-free survival (RFS) was 30.1% (95% CI 15.6-47.9) for patients with >95 CD86 + pDC per 10 5 lymphocytes, but 70.0% (95% CI 59.3-78.3) for patients with <95 CD86 + pDC (hazard ratio (HR) 3.4, 95% - CI: 1.9-6.0; P<0.0001). Moreover, only patients with <95 CD86 + pDC derived a significant benefit from longer (>8 years) TKI exposure before discontinuation (HR 0.3, 95% CI 0.1-0.8; P=0.0263). High CD86 + pDC counts significantly correlated with leukemia-specific CD8 + T - cell exhaustion (Spearman correlation: 0.74, 95%-CI: 0.21-0.92; P=0.0098). Our data demonstrate that CML patients with high CD86 + pDC counts have a higher risk of relapse after TKI discontinuation.

Correlation of Membrane Binding and Hydrophobicity to the Chaperone-Like Activity of PDC-109, the Major Protein of Bovine Seminal Plasma

PubMed Central

Sankhala, Rajeshwer S.; Damai, Rajani S.; Swamy, Musti J.

2011-01-01

The major protein of bovine seminal plasma, PDC-109 binds to choline phospholipids present on the sperm plasma membrane upon ejaculation and plays a crucial role in the subsequent events leading to fertilization. PDC-109 also shares significant similarities with small heat shock proteins and exhibits chaperone-like activity (CLA). Although the polydisperse nature of this protein has been shown to be important for its CLA, knowledge of other factors responsible for such an activity is scarce. Since surface exposure of hydrophobic residues is known to be an important factor which modulates the CLA of chaperone proteins, in the present study we have probed the surface hydrophobicity of PDC-109 using bisANS and ANS. Further, effect of phospholipids on the structure and chaperone-like activity of PDC-109 was studied. Presence of DMPC was found to increase the CLA of PDC-109 significantly, which could be due to the considerable exposure of hydrophobic regions on the lipid-protein recombinants, which can interact productively with the nonnative structures of target proteins, resulting in their protection. However, inclusion of DMPG instead of DMPC did not significantly alter the CLA of PDC-109, which could be due to the lower specificity of PDC-109 for DMPG as compared to DMPC. Cholesterol incorporation into DMPC membranes led to a decrease in the CLA of PDC-109-lipid recombinants, which could be attributed to reduced accessibility of hydrophobic surfaces to the substrate protein(s). These results underscore the relevance of phospholipid binding and hydrophobicity to the chaperone-like activity of PDC-109. PMID:21408153

Patient-Doctor Contact Interval and Clinical Outcomes in Continuous Ambulatory Peritoneal Dialysis Patients.

PubMed

Yi, Chunyan; Guo, Qunying; Lin, Jianxiong; Li, Jianying; Yu, Xueqing; Yang, Xiao

2017-01-01

The optimal patient-doctor contact (PDC) interval remains unknown in peritoneal dialysis (PD) patients. The aim was to investigate the association between PDC interval and clinical outcomes in continuous ambulatory PD (CAPD) patients. In this retrospective cohort study, CAPD patients who resided in Guangzhou city between January 2006 and December 2012 were included. According to receiver operating characteristic curve analysis, all patients were classified as high (PDC interval ≤2 months) and low (PDC interval >2 months) PDC frequency groups. Biochemical data, clinical events, and clinical outcomes during the follow-up period were compared. Of 433 CAPD patients, the mean age was 51.3 ± 15.7 years, 54.3% of patients were male, and 29.1% with diabetes. The median vintage of PD was 45.8 (26.3-69.1) months. Patients with high PDC frequency (n = 233) had better patient-survival rates (99.6, 87.7, and 76.5% vs. 92.7, 76.5, and 58.7% at 1, 3, and 5 years; p < 0.001), lower peritonitis rate (0.17 vs. 0.23 episodes per patient-year; p < 0.001), and hospitalization rate (0.49 vs. 0.67 episodes per patient-year; p < 0.001) than those in the low PDC frequency group (n = 200). After adjustment for confounders, PDC interval of no more than 2 months was independently associated with better patient survival (hazard ratio 0.60, 95% CI 0.42-0.86, p = 0.006). A PDC interval of 2 months or less was associated with better clinical outcomes in CAPD patients. This indicates that a shorter PDC interval should be encouraged for them to achieve better clinical outcomes. © 2017 S. Karger AG, Basel.

Sidechain biology and the immunogenicity of PDC-E2, the major autoantigen of primary biliary cirrhosis.

PubMed

Mao, Tin K; Davis, Paul A; Odin, Joseph A; Coppel, Ross L; Gershwin, M Eric

2004-12-01

The E2 component of mitochondrial pyruvate dehydrogenase complex (PDC-E2) is the immunodominant autoantigen of primary biliary cirrhosis. Whereas lipoylation of PDC-E2 is essential for enzymatic activity and predominates under normal conditions, other biochemical systems exist that also target the lysine residue, including acylation of fatty acids or xenobiotics and ubiquitinylation. More importantly, the immunogenicity can be affected by derivatization of the lysine residue, as the recognition of lipoylated PDC-E2 by patient autoantibodies is enhanced compared with octanoylated PDC-E2. Furthermore, our laboratory has shown that various xenobiotic modifications of a peptide representing the immunodominant region of PDC-E2 are immunoreactive against patient sera. The only purported regulatory system that prevents the accumulation of potentially autoreactive PDC-E2 is glutathionylation, in which the lysine-lipoic acid moiety is further modified with glutathione during apoptosis. Interestingly, this system is found in several cell lines, including HeLa, Jurkat, and Caco-2 cells, but not in cholangiocytes and salivary gland epithelial cells, both of which are targets for destruction in primary biliary cirrhosis. Hence, the failure of this or other regulatory system(s) may overwhelm the immune system with immunogenic PDC-E2 that can initiate the breakdown of tolerance in a genetically susceptible individual. In this review the authors survey the data available on the biochemical life of PDC-E2, with particular emphasis on the lysine residue and its known interactions with machinery involved in various posttranslational modifications.

Application of microalgae hydrolysate as a fermentation medium for microbial production of 2-pyrone 4,6-dicarboxylic acid.

PubMed

Htet, April N; Noguchi, Mana; Ninomiya, Kazuaki; Tsuge, Yota; Kuroda, Kosuke; Kajita, Shinya; Masai, Eiji; Katayama, Yoshihiro; Shikinaka, Kazuhiro; Otsuka, Yuichiro; Nakamura, Masaya; Honda, Ryo; Takahashi, Kenji

2018-06-01

Actual biomass of microalgae was tested as a fermentation substrate for microbial production of 2-pyrone 4,6-dicarboxylic acid (PDC). Acid-hydrolyzed green microalgae Chlorella emersonii (algae hydrolysate) was diluted to adjust the glucose concentration to 2 g/L and supplemented with the nutrients of Luria-Bertani (LB) medium (tryptone 10 g/L and yeast extract 5 g/L). When the algae hydrolysate was used as a fermentation source for recombinant Escherichia coli producing PDC, 0.43 g/L PDC was produced with a yield of 20.1% (mol PDC/mol glucose), whereas 0.19 g/L PDC was produced with a yield of 8.6% when LB medium supplemented with glucose was used. To evaluate the potential of algae hydrolysate alone as a fermentation medium for E. coli growth and PDC production, the nutrients of LB medium were reduced from the algae hydrolysate medium. Interestingly, 0.17 g/L PDC was produced even without additional nutrient, which was comparable to the case using pure glucose medium with nutrients of LB medium. When using a high concentration of hydrolysate without additional nutrients, 1.22 g/L PDC was produced after a 24-h cultivation with the yield of 16.1%. Overall, C. emersonii has high potential as cost-effective fermentation substrate for the microbial production of PDC. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

[Molecular genetic analysis of amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS/PDC) in the Kii peninsula].

PubMed

Hara, Kenju; Kuwano, Ryozo; Miyashita, Akinori; Kokubo, Yasumasa; Sasaki, Ryogen; Nakahara, Yasuo; Goto, Jun; Nishizawa, Masatoyo; Kuzuhara, Shigeki; Tsuji, Shoji

2007-11-01

Recent clinical research have revealed that more than 70% of the patients with ALS/PDC, which is highly prevalent in Hohara area in the Kii peninsula, have family history. 80% of Guamanian patients, who have identical pathological findings to those of ALS/PDC in Kii, are also known to have family history with non-Mendelian trait. These facts suggest strong genetic predisposition to ALS/PDC in both Kii and Guam. However, no genes associated with ALS/PDC have been identified by molecular genetic studies using candidate gene approach. To identify the causative or susceptibility genes for ALS/PDC, we have conducted a genomewide linkage analysis for five families with ALS/PDC in Hohara. The fact that affected individuals were ascertained in successive generations suggest an autosomal dominant (AD) inheritance, while the presence of consanguinity suggests an autosomal recessive (AR) inheritance. Although we can raise possibilities of AD model with incomplete penetrance or AR model with high gene frequency (pseudo-dominant model), the mode of inheritance of ALS/PDC families is complicated and controversial. Therefore, we are also conducting model-free (non-parametric) linkage analysis to identify the disease locus without setting mode of inheritance. More family members and detailed clinical evaluations are required to obtain the convincing evidence of linkage.

Effect of pH in a Pd-based ethanol membraneless air breathing nanofluidic fuel cell with flow-through electrodes

NASA Astrophysics Data System (ADS)

López-Rico, C. A.; Galindo-de-la-Rosa, J.; Ledesma-García, J.; Arriaga, L. G.; Guerra-Balcázar, M.; Arjona, N.

2015-12-01

In this work, a nanofluidic fuel cell (NFC) in which streams flow through electrodes was used to investigate the role of pH in the cell performance using ethanol as fuel and two Pd nanoparticles as electrocatalysts: one commercially available (Pd/C from ETEK) and other synthesized using ionic liquids (Pd/C IL). The cell performances for both electrocatalysts in acid/acid (anodic/cathodic) streams were of 18.05 and 9.55 mW cm-2 for Pd/C ETEK and Pd/C IL. In alkaline/alkaline streams, decrease to 15.94 mW cm-2 for Pd/C ETEK and increase to 15.37 mW cm-2 for Pd/C IL. In alkaline/acidic streams both electrocatalysts showed similar cell voltages (up to 1 V); meanwhile power densities were of 87.6 and 99.4 mW cm-2 for Pd/C ETEK and Pd/C IL. The raise in cell performance can be related to a decrease in activation losses, the combined used of alkaline and acidic streams and these high values compared with flow-over fuel cells can be related to the enhancement of the cathodic mass transport by using three dimensional porous electrodes and two sources of oxygen: from air and from a saturated solution.

Borehole instability analysis for IODP Site C0002 of the NanTroSEIZE Project, Nankai Trough subduction zone

NASA Astrophysics Data System (ADS)

Wu, H.; Kido, Y. N.; Kinoshita, M.; Saito, S.

2013-12-01

Wellbore instability is a major challenge for the engineer evaluating borehole and formation conditions. Instability is especially important to understand in areas with high stress variations, significant structure anisotropy, or pre-existing fracture systems. Borehole (in)stability is influenced by rock strength, structural properties, and near-field principal stresses. During drilling, the borehole conditions also impact borehole integrity. Factors that we can measure in the borehole during with logging while drilling (LWD) to understand these conditions include mud weight, mud loss, ROP (Rate of Penetration), RPM (Rotation Per Minute), WOB (Weight on Bit), and TORQ (Power swivel torque value). We conducted borehole instability analysis for Site C0002 of the Nankai Trough transect based on riser and riserless drilling during IODP Expedition 338. The borehole shape, determined from LWD resistivity images, indicates that most of drilling occurred in stable environments, however, in a few instances the bottom hole assembly became stuck. We used our stress profile model to evaluate the mud weight required to drill a stable borehole for the estimated rock strength and physical properties. Based on our analysis, we interpret that borehole instability during IODP Expedition 338 may have been caused by weak bedding plane and fluid overpressure state. Future work with this model will investigate the roles of these conditions.

Ultrasonic/Sonic Jackhammer

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoseph (Inventor); Herz, Jack L. (Inventor); Sherrit, Stewart (Inventor)

2014-01-01

The invention provides a novel jackhammer that utilizes ultrasonic and/or sonic vibrations as source of power. It is easy to operate and does not require extensive training, requiring substantially less physical capabilities from the user and thereby increasing the pool of potential operators. An important safety benefit is that it does not fracture resilient or compliant materials such as cable channels and conduits, tubing, plumbing, cabling and other embedded fixtures that may be encountered along the impact path. While the ultrasonic/sonic jackhammer of the invention is able to cut concrete and asphalt, it generates little back-propagated shocks or vibrations onto the mounting fixture, and can be operated from an automatic platform or robotic system. PNEUMATICS; ULTRASONICS; IMPACTORS; DRILLING; HAMMERS BRITTLE MATERIALS; DRILL BITS; PROTOTYPES; VIBRATION

Enhanced optical and electrochemical properties of polyaniline/cobalt oxide nano composite

NASA Astrophysics Data System (ADS)

Niranjana, M.; Yesappa, L.; Ashokkumar, S. P.; Vijeth, H.; Basappa, M.; Devendrappa, H.

2018-05-01

Polyaniline and its composites at different wt. % of Cobalt oxide nano (PDC1, PDC2 and PDC5) were prepared by in-situ chemical reaction method The optical property was carried out using UV-Vis. Absorption Spectroscopy. The electrochemical property like cyclic voltammetry and galvonostatic charging-discharging was carried out for PANI and PDC nanocomposite electrode materials. A specific capacitance of 212.08 F/g and 336.41 F/g with scan rates 100 and 200 mV/s at 0.4 A/g current density respectively. These results are suggesting PDC composite is a prominent candidate for supercapacitor properties applications.

Plasmacytoid Dendritic Cells Die by the CD8 T Cell-Dependent Perforin Pathway during Acute Nonviral Inflammation.

PubMed

Mossu, Adrien; Daoui, Anna; Bonnefoy, Francis; Aubergeon, Lucie; Saas, Philippe; Perruche, Sylvain

2016-09-01

Regulation of the inflammatory response involves the control of dendritic cell survival. To our knowledge, nothing is known about the survival of plasmacytoid dendritic cells (pDC) in such situation. pDC are specialized in type I IFN (IFN-I) secretion to control viral infections, and IFN-I also negatively regulate pDC survival during the course of viral infections. In this study, we asked about pDC behavior in the setting of virus-free inflammation. We report that pDC survival was profoundly reduced during different nonviral inflammatory situations in the mouse, through a mechanism independent of IFN-I and TLR signaling. Indeed, we demonstrated that during inflammation, CD8(+) T cells induced pDC apoptosis through the perforin pathway. The data suggest, therefore, that pDC have to be turned down during ongoing acute inflammation to not initiate autoimmunity. Manipulating CD8(+) T cell response may therefore represent a new therapeutic opportunity for the treatment of pDC-associated autoimmune diseases, such as lupus or psoriasis. Copyright © 2016 by The American Association of Immunologists, Inc.

Detection of discoloration and decay in living trees and utility poles

Treesearch

Alex L. Shigo; Alex Shigo

1974-01-01

A method is described for detecting discoloration and decay in living trees and creosoted utility poles. The method and devices have come from research involving many people over a seven-year period. A probe was inserted into a 3/32-inch (2.4 mm) diameter hole made by drill bits 8 inches (20.32 cm) and 12 inches (30.48 cm) long mounted in a portable, light-weight,...

Reprographics Career Ladder AFSC 703X0.

DTIC Science & Technology

1988-02-01

paper by hand adjust stitchers pack printed materials manually wax drill bit ends VI. PRODUCTION CONTROL PERSONNEL CLUSTER (STG033, N=38). Comprising...work requests notify customer of completed work verify duplicating requests maintain job logs manually 16 Two jobs were identified within this...E146 MAINTAIN LOGS OF JOBS PROCESSED 47 E138 DISTRIBUTE COMPLETED PRODUCTS 47 N441 MAINTAIN JOB LOGS MANUALLY 43 E169 PROCESS INCOMING DISTRIBUTION 6.l

DOD Inventory of Contracted Services: Actions Needed to Help Ensure Inventory Data Are Complete and Accurate

DTIC Science & Technology

2015-11-01

for Personnel and Readiness NAVSEA Naval Sea Systems Command OFPP Office of Federal Procurement Policy OMB Office of Management and Budget PDC ...Documentation of Contractors ( PDC ) process is delegated to the manpower and programing functions at the commands. The PDC process collects information from...review results. Army’s PDC tool, used to inform the inventory review, tracks by location and functional requirement—such as administrative or

Interaction of mammalian seminal plasma protein PDC-109 with cholesterol: implications for a putative CRAC domain.

PubMed

Scolari, Silvia; Müller, Karin; Bittman, Robert; Herrmann, Andreas; Müller, Peter

2010-10-26

Seminal plasma proteins of the fibronectin type II (Fn2) family modulate mammalian spermatogenesis by triggering the release of the lipids phosphatidylcholine and cholesterol from sperm cells. Whereas the specific interaction of these proteins with phosphatidylcholine is well-understood, their selectivity for cholesterol is unknown. To characterize the interaction between the bovine Fn2 protein PDC-109 and cholesterol, we have investigated the effect of PDC-109 on the dynamics of fluorescent cholesterol analogues in lipid vesicles by time-resolved fluorescence anisotropy. The data show that PDC-109 decreases the rotational mobility of cholesterol within the membrane and that the extent of this impact depends on the cholesterol structure, indicating a specific influence of PDC-109 on cholesterol. We propose that the cholesterol recognition/interaction amino acid consensus (CRAC) regions of PDC-109 are involved in the interaction with cholesterol.

Plasmacytoid Dendritic Cells: Neglected Regulators of the Immune Response to Staphylococcus aureus

PubMed Central

Bekeredjian-Ding, Isabelle; Greil, Johann; Ammann, Sandra; Parcina, Marijo

2014-01-01

Plasmacytoid dendritic cells (pDC) are a rare subset of leukocytes equipped with Fcγ and Fcε receptors, which exert contrary effects on sensing of microbial nucleic acids by endosomal Toll-like receptors. In this article, we explain how pDC contribute to the immune response to Staphylococcus aureus. Under normal circumstances the pDC participates in the memory response to the pathogen: pDC activation is initiated by uptake of staphylococcal immune complexes with IgG or IgE. However, protein A-expressing S. aureus strains additionally trigger pDC activation in the absence of immunoglobulin. In this context, staphylococci exploit the pDC to induce antigen-independent differentiation of IL-10 producing plasmablasts, an elegant means to propagate immune evasion. We further discuss the role of type I interferons in infection with S. aureus and the implications of these findings for the development of immune based therapies and vaccination. PMID:24904586

Improvement of ethanol production by recombinant expression of pyruvate decarboxylase in the white-rot fungus Phanerochaete sordida YK-624.

PubMed

Wang, Jianqiao; Hirabayashi, Sho; Mori, Toshio; Kawagishi, Hirokazu; Hirai, Hirofumi

2016-07-01

To improve ethanol production by Phanerochaete sordida YK-624, the pyruvate decarboxylase (PDC) gene was cloned from and reintroduced into this hyper lignin-degrading fungus; the gene encodes a key enzyme in alcoholic fermentation. We screened 16 transformant P. sordida YK-624 strains that each expressed a second, recombinant PDC gene (pdc) and then identified the transformant strain (designated GP7) with the highest ethanol production. Direct ethanol production from hardwood was 1.41 higher with GP7 than with wild-type P. sordida YK-624. RT-PCR analysis indicated that the increased PDC activity was caused by elevated recombinant pdc expression. Taken together, these results suggested that ethanol production by P. sordida YK-624 can be improved by the stable expression of an additional, recombinant pdc. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Rapamycin has suppressive and stimulatory effects on human plasmacytoid dendritic cell functions

PubMed Central

Boor, P P C; Metselaar, H J; Mancham, S; van der Laan, L J W; Kwekkeboom, J

2013-01-01

Plasmacytoid dendritic cells (PDC) are involved in innate immunity by interferon (IFN)-α production, and in adaptive immunity by stimulating T cells and inducing generation of regulatory T cells (Treg). In this study we studied the effects of mammalian target of rapamycin (mTOR) inhibition by rapamycin, a commonly used immunosuppressive and anti-cancer drug, on innate and adaptive immune functions of human PDC. A clinically relevant concentration of rapamycin inhibited Toll-like receptor (TLR)-7-induced IFN-α secretion potently (−64%) but TLR-9-induced IFN-α secretion only slightly (−20%), while the same concentration suppressed proinflammatory cytokine production by TLR-7-activated and TLR-9-activated PDC with similar efficacy. Rapamycin inhibited the ability of both TLR-7-activated and TLR-9-activated PDC to stimulate production of IFN-γ and interleukin (IL)-10 by allogeneic T cells. Surprisingly, mTOR-inhibition enhanced the capacity of TLR-7-activated PDC to stimulate naive and memory T helper cell proliferation, which was caused by rapamycin-induced up-regulation of CD80 expression on PDC. Finally, rapamycin treatment of TLR-7-activated PDC enhanced their capacity to induce CD4+forkhead box protein 3 (FoxP3)+ regulatory T cells, but did not affect the generation of suppressive CD8+CD38+lymphocyte activation gene (LAG)-3+ Treg. In general, rapamycin inhibits innate and adaptive immune functions of TLR-stimulated human PDC, but enhances the ability of TLR-7-stimulated PDC to stimulate CD4+ T cell proliferation and induce CD4+FoxP3+ regulatory T cell generation. PMID:23968562

Surface drilling technologies for Mars

NASA Technical Reports Server (NTRS)

Blacic, J. D.; Rowley, J. C.; Cort, G. E.

1986-01-01

Rock drilling and coring conceptual designs for the surface activities associated with a manned Mars mission are proposed. Straightforward extensions of equipment and procedures used on Earth are envisioned for the sample coring and shallow high explosive shot holes needed for tunneling and seismic surveying. A novel rocket exhaust jet piercing method is proposed for very rapid drilling of shot holes required for explosive excavation of emergency radiation shelters. Summaries of estimated equipment masses and power requirements are provided, and the indicated rotary coring rigs are scaled from terrestrial equipment and use compressed CO2 from the Martian atmosphere for core bit cooling and cuttings removal. A mass of 120 kg and power of 3 kW(e) are estimated for a 10 m depth capability. A 100 m depth capacity core rig requires about 1150 kg and 32 km(e). The rocket exhaust jet equipment devised for shallow (3m) explosive emplacement shot holes requires no surface power beyond an electrical ignition system, and might have a 15 kg mass.

The In-Situ One-Step Synthesis of a PDC Macromolecular Pro-Drug and the Fabrication of a Novel Core-Shell Micell.

PubMed

Yu, Cui-Yun; Yang, Sa; Li, Zhi-Ping; Huang, Can; Ning, Qian; Huang, Wen; Yang, Wen-Tong; He, Dongxiu; Sun, Lichun

2016-01-01

The development of slow release nano-sized carriers for efficient antineoplastic drug delivery with a biocompatible and biodegradable pectin-based macromolecular pro-drug for tumor therapy has been reported in this study. Pectin-doxorubicin conjugates (PDC), a macromolecular pro-drug, were prepared via an amide condensation reaction, and a novel amphiphilic core-shell micell based on a PDC macromolecular pro-drug (PDC-M) was self-assembled in situ, with pectin as the hydrophilic shell and doxorubicin (DOX) as the hydrophobic core. Then the chemical structure of the PDC macromolecular pro-drug was identified by both Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy ((1)H-NMR), and proved that doxorubicin combined well with the pectin and formed macromolecular pro-drug. The PDC-M were observed to have an unregularly spherical shape and were uniform in size by scanning electron microscopy (SEM). The average particle size of PDC-M, further measured by a Zetasizer nanoparticle analyzer (Nano ZS, Malvern Instruments), was about 140 nm. The encapsulation efficiency and drug loading were 57.82% ± 3.7% (n = 3) and 23.852% ±2.3% (n = 3), respectively. The in vitro drug release behaviors of the resulting PDC-M were studied in a simulated tumor environment (pH 5.0), blood (pH 7.4) and a lysosome media (pH 6.8), and showed a prolonged slow release profile. Assays for antiproliferative effects and flow cytometry of the resulting PDC-M in HepG2 cell lines demonstrated greater properties of delayed and slow release as compared to free DOX. A cell viability study against endothelial cells further revealed that the resulting PDC-M possesses excellent cell compatibilities and low cytotoxicities in comparison with that of the free DOX. Hemolysis activity was investigated in rabbits, and the results also demonstrated that the PDC-M has greater compatibility in comparison with free DOX. This shows that the resulting PDC-M can ameliorate the hydrophobicity of free DOX. This work proposes a novel strategy for in-situ one-step synthesis of macromolecular pro-drugs and fabrication of a core-shell micelle, demonstrating great potential for cancer chemotherapy.

Sample Acqusition Drilling System for the the Resource Prospector Mission

NASA Astrophysics Data System (ADS)

Zacny, K.; Paulsen, G.; Quinn, J.; Smith, J.; Kleinhenz, J.

2015-12-01

The goal of the Lunar Resource Prospector Mission (RPM) is to capture and identify volatiles species within the top meter of the lunar regolith. The RPM drill has been designed to 1. Generate cuttings and place them on the surface for analysis by the the Near InfraRed Volatiles Spectrometer Subsystem (NIRVSS), and 2. Capture cuttings and transfer them to the Oxygen and Volatile Extraction Node (OVEN) coupled with the Lunar Advanced Volatiles Analysis (LAVA) subsystem. The RPM drill is based on the Mars Icebreaker drill developed for capturing samples of ice and ice cemented ground on Mars. The drill weighs approximately 10 kg and is rated at ~300 Watt. It is a rotary-percussive, fully autonomous system designed to capture cuttings for analysis. The drill consists of: 1. Rotary-Percussive Drill Head, 2. Sampling Auger, 3. Brushing station, 4. Z-stage, 5. Deployment stage. To reduce sample handling complexity, the drill auger is designed to capture cuttings as opposed to cores. High sampling efficiency is possible through a dual design of the auger. The lower section has deep and low pitch flutes for retaining of cuttings. The upper section has been designed to efficiently move the cuttings out of the hole. The drill uses a "bite" sampling approach where samples are captured in ~10 cm intervals. The first generation drill was tested in Mars chamber as well as in Antarctica and the Arctic. It demonstrated drilling at 1-1-100-100 level (1 meter in 1 hour with 100 Watt and 100 N Weight on Bit) in ice, ice cemented ground, soil, and rocks. The second generation drill was deployed on a Carnegie Mellon University rover, called Zoe, and tested in Atacama in 2012. The tests demonstrated fully autonomous sample acquisition and delivery to a carousel. The third generation drill was tested in NASA GRC's vacuum chamber, VF13, at 10-5 torr and approximately 200 K. It demonstrated successful capture and transfer of icy samples to a crucible. The drill has been modified and integrated onto the NASA JSC RPM rover. It has been undergoing testing in a lab and in the field during the Summer of 2015.

The 2002 NIMH Provisional Diagnostic Criteria for Depression of Alzheimer's Disease (PDC-dAD): Gauging their Validity over a Decade Later.

PubMed

Sepehry, Amir A; Lee, Philip E; Hsiung, Ging-Yuek R; Beattie, B Lynn; Feldman, Howard H; Jacova, Claudia

2017-01-01

Presented herein is evidence for criterion, content, and convergent/discriminant validity of the NIMH-Provisional Diagnostic Criteria for depression of Alzheimer's Disease (PDC-dAD) that were formulated to address depression in Alzheimer's disease (AD). Using meta-analytic and systematic review methods, we examined criterion validity evidence in epidemiological and clinical studies comparing the PDC-dAD to Diagnostic and Statistical Manual of Mental Disorders fourth edition (DSM-IV), and International Classification of Disease (ICD 9) depression diagnostic criteria. We estimated prevalence of depression by PDC, DSM, and ICD with an omnibus event rate effect-size. We also examined diagnostic agreement between PDC and DSM. To gauge content validity, we reviewed rates of symptom endorsement for each diagnostic approach. Finally, we examined the PDC's relationship with assessment scales (global cognition, neuropsychiatric, and depression definition) for convergent validity evidence. The aggregate evidence supports the validity of the PDC-dAD. Our findings suggest that depression in AD differs from other depressive disorders including Major Depressive Disorder (MDD) in that dAD is more prevalent, with generally a milder presentation and with unique features not captured by the DSM. Although the PDC are the current standard for diagnosis of depression in AD, we identified the need for their further optimization based on predictive validity evidence.

Differential epitope mapping of antibodies to PDC-E2 in patients with hematologic malignancies after allogeneic hematopoietic stem cell transplantation and primary biliary cirrhosis.

PubMed

Bellucci, Roberto; Oertelt, Sabine; Gallagher, Meagan; Li, Sigui; Zorn, Emmanuel; Weller, Edie; Porcheray, Fabrice; Alyea, Edwin P; Soiffer, Robert J; Munshi, Nikhil C; Gershwin, M Eric; Ritz, Jerome

2007-03-01

A unique characteristic of the autoimmune liver disease primary biliary cirrhosis (PBC) is the presence of high-titer and extremely specific autoantibodies to the E2 component of the pyruvate dehydrogenase complex (PDC-E2). Autoantibodies to PDC-E2 antigen have only been detected in patients with disease or in those who subsequently develop PBC. One exception has been a subgroup of patients with multiple myeloma (MM) who underwent allogeneic hematopoietic stem cell transplantation (HSCT) and received donor lymphocyte infusions (DLIs) after transplantation. These patients developed high-titer antibodies to a variety of myeloma-associated antigens, including PDC-E2, coincident with rejection of myeloma cells in vivo. To examine the specificity of autoantibodies to PDC in these patients, we screened sera from patients with MM, chronic leukemias, monoclonal gammopathy of unknown significance (MGUS), PBC, and healthy donors. Three of 11 patients with MM (27%) and 2 of 6 patients with chronic leukemias (33%) developed anti-PDC-E2 antibodies in association with DLI response; 2 of 12 (17%) patients in the MGUS pretreatment control population also had detectable anti-PDC responses. Interestingly, the epitope specificity of these PDC-E2 autoantibodies was distinctive, suggesting that the mechanisms leading to loss of tolerance in the transplantation patients are distinct from PBC.

Pyroclastic density current dynamics and associated hazards at ice-covered volcanoes

NASA Astrophysics Data System (ADS)

Dufek, J.; Cowlyn, J.; Kennedy, B.; McAdams, J.

2015-12-01

Understanding the processes by which pyroclastic density currents (PDCs) are emplaced is crucial for volcanic hazard prediction and assessment. Snow and ice can facilitate PDC generation by lowering the coefficient of friction and by causing secondary hydrovolcanic explosions, promoting remobilisation of proximally deposited material. Where PDCs travel over snow or ice, the reduction in surface roughness and addition of steam and meltwater signficantly changes the flow dynamics, affecting PDC velocities and runout distances. Additionally, meltwater generated during transit and after the flow has come to rest presents an immediate secondary lahar hazard that can impact areas many tens of kilometers beyond the intial PDC. This, together with the fact that deposits emplaced on ice are rarely preserved means that PDCs over ice have been little studied despite the prevalence of summit ice at many tall stratovolcanoes. At Ruapehu volcano in the North Island of New Zealand, a monolithologic welded PDC deposit with unusually rounded clasts provides textural evidence for having been transported over glacial ice. Here, we present the results of high-resolution multiphase numerical PDC modeling coupled with experimentaly determined rates of water and steam production for the Ruapehu deposits in order to assess the effect of ice on the Ruapehu PDC. The results suggest that the presence of ice significantly modified the PDC dynamics, with implications for assessing the PDC and associated lahar hazards at Ruapehu and other glaciated volcanoes worldwide.

Effect of plasma treatments on the steam-sour gas resistance and lubricity of elastomers. [Rubbers used: copoly(ethene-propene); copoly(1,1-difluoroethane-hexafluoropropene); copoly(2-propenenitrile-1,3 butadiene); plasma polymerized tetrafluoroethane

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

Arnold, C. Jr.; Bieg, K.W.; Cuthrell, R.E.

1982-03-01

Elastomers are widely used in drilling and logging applications as static seals such as casing packers and dynamic seals such as o-rings for drill bits. Static seals often fail in service because of thermochemical degradation due to the combined effects of steam and sour gas at elevated temperatures that are characteristic of deep wells. Dynamic seals frequently fail because of abrasive wear that occurs even at the low temperatures that prevail in shallow wells. We have shown that improved steam-sour gas resistance of a fully formulated ethylene-propylene rubber at elevated temperatures can be achieved by coating the rubber with amore » thin film of plasma polymerized tetrafluoroethylene. Thus, no change in the mechanical properties of the coated rubber was observed after exposure to steam and sour gas at 275/sup 0/C for 48 h. In contrast, the shear modulus of the upcoated rubber increased by 96% after the same exposure. While the effectiveness of the fluorocarbon coating decreased at longer exposure times, short-term protection of elastomers could be beneficial in certain logging operations. It was also found that the coefficient of friction of a nitrile rubber (Buna N) was reduced by 20% after treatment with a carbon tetrafluoride plasma. This enhanced lubricity could lead to better wear characteristics in conventional drill bits where the seal is in contact with a moving metal surface. The surfaces of the plasma treated elastomers were characterized by water contact angle, scanning electron microscopy, and electron spectroscopy for chemical analysis.« less

Modeling of Methane Migration in Shallow Aquifers from Shale Gas Well Drilling.

PubMed

Zhang, Liwei; Soeder, Daniel J

2016-05-01

The vertical portion of a shale gas well, known as the "tophole" is often drilled using an air-hammer bit that may introduce pressures as high as 2400 kPa (350 psi) into groundwater while penetrating shallow aquifers. A 3-D TOUGH2 model was used to simulate the flow of groundwater under the high hydraulic heads that may be imposed by such trapped compressed air, based on an observed case in West Virginia (USA) in 2012. The model realizations show that high-pressure air trapped in aquifers may cause groundwater to surge away from the drill site at observable velocities. If dissolved methane is present within the aquifer, the methane can be entrained and transported to a maximum distance of 10.6 m per day. Results from this study suggest that one cause of the reported increase in methane concentrations in groundwater near shale gas production wells may be the transport of pre-existing methane via groundwater surges induced by air drilling, not necessarily direct natural gas leakage from the unconventional gas reservoir. The primary transport mechanisms are advective transport of dissolved methane with water flow, and diffusive transport of dissolved methane. © 2015, National Ground Water Association.

Experimental study of improved rheology and lubricity of drilling fluids enhanced with nano-particles

NASA Astrophysics Data System (ADS)

Bég, O. Anwar; Espinoza, D. E. Sanchez; Kadir, Ali; Shamshuddin, MD.; Sohail, Ayesha

2018-04-01

An experimental study of the rheology and lubricity properties of a drilling fluid is reported, motivated by applications in highly deviated and extended reach wells. Recent developments in nanofluids have identified that the judicious injection of nano-particles into working drilling fluids may resolve a number of issues including borehole instability, lost circulation, torque and drag, pipe sticking problems, bit balling and reduction in drilling speed. The aim of this article is, therefore, to evaluate the rheological characteristics and lubricity of different nano-particles in water-based mud, with the potential to reduce costs via a decrease in drag and torque during the construction of highly deviated and ERD wells. Extensive results are presented for percentage in torque variation and coefficient of friction before and after aging. Rheology is evaluated via apparent viscosity, plastic viscosity and gel strength variation before and after aging for water-based muds (WBM). Results are included for silica and titanium nano-particles at different concentrations. These properties were measured before and after aging the mud samples at 80 °C during 16 h at static conditions. The best performance was shown with titanium nano-particles at a concentration of 0.60% (w/w) before aging.

Enzymatic testing sensitivity, variability and practical diagnostic algorithm for pyruvate dehydrogenase complex (PDC) deficiency.

PubMed

Shin, Ha Kyung; Grahame, George; McCandless, Shawn E; Kerr, Douglas S; Bedoyan, Jirair K

2017-11-01

Pyruvate dehydrogenase complex (PDC) deficiency is a major cause of primary lactic acidemia in children. Prompt and correct diagnosis of PDC deficiency and differentiating between specific vs generalized, or secondary deficiencies has important implications for clinical management and therapeutic interventions. Both genetic and enzymatic testing approaches are being used in the diagnosis of PDC deficiency. However, the diagnostic efficacy of such testing approaches for individuals affected with PDC deficiency has not been systematically investigated in this disorder. We sought to evaluate the diagnostic sensitivity and variability of the various PDC enzyme assays in females and males at the Center for Inherited Disorders of Energy Metabolism (CIDEM). CIDEM data were filtered by lactic acidosis and functional PDC deficiency in at least one cell/tissue type (blood lymphocytes, cultured fibroblasts or skeletal muscle) identifying 186 subjects (51% male and 49% female), about half were genetically resolved with 78% of those determined to have a pathogenic PDHA1 mutation. Assaying PDC in cultured fibroblasts in cases where the underlying genetic etiology is PDHA1, was highly sensitive irrespective of gender; 97% (95% confidence interval [CI]: 90%-100%) and 91% (95% CI: 82%-100%) in females and males, respectively. In contrast to the fibroblast-based testing, the lymphocyte- and muscle-based testing were not sensitive (36% [95% CI: 11%-61%, p=0.0003] and 58% [95% CI: 30%-86%, p=0.014], respectively) for identifying known PDC deficient females with pathogenic PDHA1 mutations. In males with a known PDHA1 mutation, the sensitivity of the various cell/tissue assays (75% lymphocyte, 91% fibroblast and 88% muscle) were not statistically different, and the discordance frequency due to the specific cell/tissue used for assaying PDC was 0.15±0.11. Based on this data, a practical diagnostic algorithm is proposed accounting for current molecular approaches, enzyme testing sensitivity, and variability due to gender, cell/tissue type used for testing, and successive repeat testing. Copyright © 2017 Elsevier Inc. All rights reserved.

Recent insights into the implications of metabolism in plasmacytoid dendritic cell innate functions: Potential ways to control these functions.

PubMed

Saas, Philippe; Varin, Alexis; Perruche, Sylvain; Ceroi, Adam

2017-01-01

There are more and more data concerning the role of cellular metabolism in innate immune cells, such as macrophages or conventional dendritic cells. However, few data are available currently concerning plasmacytoid dendritic cells (PDC), another type of innate immune cells. These cells are the main type I interferon (IFN) producing cells, but they also secrete other pro-inflammatory cytokines (e.g., tumor necrosis factor or interleukin [IL]-6) or immunomodulatory factors (e.g., IL-10 or transforming growth factor-β). Through these functions, PDC participate in antimicrobial responses or maintenance of immune tolerance, and have been implicated in the pathophysiology of several autoimmune diseases, as well as in tumor immune escape mechanisms. Recent data support the idea that the glycolytic pathway (or glycolysis), as well as lipid metabolism (including both cholesterol and fatty acid metabolism) may impact some innate immune functions of PDC or may be involved in these functions after Toll-like receptor (TLR) 7/9 triggering. The kinetics of glycolysis after TLR7/9 triggering may differ between human and murine PDC. In mouse PDC, metabolism changes promoted by TLR7/9 activation may depend on an autocrine/paracrine loop, implicating type I IFN and its receptor IFNAR. This could explain a delayed glycolysis in mouse PDC. Moreover, PDC functions can be modulated by the metabolism of cholesterol and fatty acids. This may occur via the production of lipid ligands that activate nuclear receptors (e.g., liver X receptor [LXR]) in PDC or through limiting intracellular cholesterol pool size (by statin or LXR agonist treatment) in these cells. Finally, lipid-activated nuclear receptors (i.e., LXR or peroxisome proliferator activated receptor) may also directly interact with pro-inflammatory transcription factors, such as NF-κB. Here, we discuss how glycolysis and lipid metabolism may modulate PDC functions and how this may be harnessed in pathological situations where PDC play a detrimental role.

Recent insights into the implications of metabolism in plasmacytoid dendritic cell innate functions: Potential ways to control these functions

PubMed Central

Saas, Philippe; Varin, Alexis; Perruche, Sylvain; Ceroi, Adam

2017-01-01

There are more and more data concerning the role of cellular metabolism in innate immune cells, such as macrophages or conventional dendritic cells. However, few data are available currently concerning plasmacytoid dendritic cells (PDC), another type of innate immune cells. These cells are the main type I interferon (IFN) producing cells, but they also secrete other pro-inflammatory cytokines (e.g., tumor necrosis factor or interleukin [IL]-6) or immunomodulatory factors (e.g., IL-10 or transforming growth factor-β). Through these functions, PDC participate in antimicrobial responses or maintenance of immune tolerance, and have been implicated in the pathophysiology of several autoimmune diseases, as well as in tumor immune escape mechanisms. Recent data support the idea that the glycolytic pathway (or glycolysis), as well as lipid metabolism (including both cholesterol and fatty acid metabolism) may impact some innate immune functions of PDC or may be involved in these functions after Toll-like receptor (TLR) 7/9 triggering. The kinetics of glycolysis after TLR7/9 triggering may differ between human and murine PDC. In mouse PDC, metabolism changes promoted by TLR7/9 activation may depend on an autocrine/paracrine loop, implicating type I IFN and its receptor IFNAR. This could explain a delayed glycolysis in mouse PDC. Moreover, PDC functions can be modulated by the metabolism of cholesterol and fatty acids. This may occur via the production of lipid ligands that activate nuclear receptors (e.g., liver X receptor [LXR]) in PDC or through limiting intracellular cholesterol pool size (by statin or LXR agonist treatment) in these cells. Finally, lipid-activated nuclear receptors (i.e., LXR or peroxisome proliferator activated receptor) may also directly interact with pro-inflammatory transcription factors, such as NF-κB. Here, we discuss how glycolysis and lipid metabolism may modulate PDC functions and how this may be harnessed in pathological situations where PDC play a detrimental role. PMID:28580131

Directional connectivity of resting state human fMRI data using cascaded ICA-PDC analysis.

PubMed

Silfverhuth, Minna J; Remes, Jukka; Starck, Tuomo; Nikkinen, Juha; Veijola, Juha; Tervonen, Osmo; Kiviniemi, Vesa

2011-11-01

Directional connectivity measures, such as partial directed coherence (PDC), give us means to explore effective connectivity in the human brain. By utilizing independent component analysis (ICA), the original data-set reduction was performed for further PDC analysis. To test this cascaded ICA-PDC approach in causality studies of human functional magnetic resonance imaging (fMRI) data. Resting state group data was imaged from 55 subjects using a 1.5 T scanner (TR 1800 ms, 250 volumes). Temporal concatenation group ICA in a probabilistic ICA and further repeatability runs (n = 200) were overtaken. The reduced data-set included the time series presentation of the following nine ICA components: secondary somatosensory cortex, inferior temporal gyrus, intracalcarine cortex, primary auditory cortex, amygdala, putamen and the frontal medial cortex, posterior cingulate cortex and precuneus, comprising the default mode network components. Re-normalized PDC (rPDC) values were computed to determine directional connectivity at the group level at each frequency. The integrative role was suggested for precuneus while the role of major divergence region may be proposed to primary auditory cortex and amygdala. This study demonstrates the potential of the cascaded ICA-PDC approach in directional connectivity studies of human fMRI.

An efficient method for gene silencing in human primary plasmacytoid dendritic cells: silencing of the TLR7/IRF-7 pathway as a proof of concept

PubMed Central

Smith, Nikaïa; Vidalain, Pierre-Olivier; Nisole, Sébastien; Herbeuval, Jean-Philippe

2016-01-01

Plasmacytoid dendritic cells (pDC) are specialized immune cells that produce massive levels of type I interferon in response to pathogens. Unfortunately, pDC are fragile and extremely rare, rendering their functional study a tough challenge. However, because of their central role in numerous pathologies, there is a considerable need for an efficient and reproducible protocol for gene silencing in these cells. In this report, we tested six different methods for siRNA delivery into primary human pDC including viral-based, lipid-based, electroporation, and poly-ethylenimine (PEI) technologies. We show that lipid-based reagent DOTAP was extremely efficient for siRNA delivery into pDC, and did not induce cell death or pDC activation. We successfully silenced Toll-Like Receptor 7 (TLR7), CXCR4 and IFN regulatory factor 7 (IRF-7) gene expression in pDC as assessed by RT-qPCR or cytometry. Finally, we showed that TLR7 or IRF-7 silencing in pDC specifically suppressed IFN-α production upon stimulation, providing a functional validation of our transfection protocol. PMID:27412723

Molecular identification and characterization of the pyruvate decarboxylase gene family associated with latex regeneration and stress response in rubber tree.

PubMed

Long, Xiangyu; He, Bin; Wang, Chuang; Fang, Yongjun; Qi, Jiyan; Tang, Chaorong

2015-02-01

In plants, ethanolic fermentation occurs not only under anaerobic conditions but also under aerobic conditions, and involves carbohydrate and energy metabolism. Pyruvate decarboxylase (PDC) is the first and the key enzyme of ethanolic fermentation, which branches off the main glycolytic pathway at pyruvate. Here, four PDC genes were isolated and identified in a rubber tree, and the protein sequences they encode are very similar. The expression patterns of HbPDC4 correlated well with tapping-simulated rubber productivity in virgin rubber trees, indicating it plays an important role in regulating glycometabolism during latex regeneration. HbPDC1, HbPDC2 and HbPDC3 had striking expressional responses in leaves and bark to drought, low temperature and high temperature stresses, indicating that the HbPDC genes are involve in self-protection and defense in response to various abiotic and biotic stresses during rubber tree growth and development. To understand ethanolic fermentation in rubber trees, it will be necessary to perform an in-depth study of the regulatory pathways controlling the HbPDCs in the future. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Histone deacetylase inhibitor valproic acid affects plasmacytoid dendritic cells phenotype and function.

PubMed

Arbez, Jessy; Lamarthée, Baptiste; Gaugler, Béatrice; Saas, Philippe

2014-08-01

Plasmacytoid dendritic cells (PDC) represent a rare subset of dendritic cells specialized in the production of type I IFN in response to microbial pathogens. Recent data suggested that histone deacetylase (HDAC) inhibitors possess potent immunomodulatory properties both in vitro and in vivo. In this study, we assayed the ability of the HDAC inhibitor, valproic acid (VPA), to influence the phenotype and functional properties of human PDC isolated from peripheral blood. We showed that VPA inhibited the production of IFN-α and the proinflammatory cytokines TNF-α and IL-6 by CpG-activated PDC. VPA also affected the phenotype of PDC by reducing the expression of costimulatory molecules induced by CpG activation. Moreover, VPA reduced the capacity of CpG-stimulated PDC to promote CD4(+) T cell proliferation and IFN-γ production, while enhancing the proportion of IL-10 positive T cells. These results suggest that HDAC inhibition by VPA alters essential human PDC functions, highlighting the need for monitoring immune functions in cancer patients receiving HDAC inhibitors, but also making these drugs attractive therapies in inflammatory, and autoimmune diseases implicating PDC. Copyright © 2014 Elsevier GmbH. All rights reserved.

Bovine seminal PDC-109 protein: an overview of biochemical and functional properties.

PubMed

Srivastava, N; Jerome, A; Srivastava, S K; Ghosh, S K; Kumar, Amit

2013-04-01

Although long-term storage of bovine semen is desirable for wider use, successful cryopreservation depends on several factors, including various proteins present in seminal plasma. One such group of proteins, viz. bovine seminal plasma (BSP) proteins represents the major protein fraction in bovine seminal plasma. They constitute three major heparin-binding (HB-) acidic proteins secreted by seminal vesicles, viz. BSP-A1/-A2 (PDC-109), BSP-A3 and BSP-30-kDa. By purification studies it was deduced that PDC-109 is a polypeptide of 109 amino acids and contains two tandem repeating fibronectin type-II (Fn-II) domains, preceded by a 23 residue N-terminal domain. Though BSP-A1 and BSP-A2 are biochemically similar they differ only in glycosylation and their mixture is called PDC-109 or gonadostatins. PDC-109 exists as a polydisperse, multimeric self-associated molecule and possesses multifunctional properties, viz. binding to the surface of plasma membrane of spermatozoa causing conformational change in the sperm surface proteins and enhances motility. Besides binding, PDC-109 protein provokes cholesterol efflux from sperm membrane and promotes sperm reservoir by interacting with oviductal membrane. Interaction of sperm with PDC-109 protein induces sperm capacitation and acrosome reaction. However, prolonged exposure of spermatozoa with free floating PDC-109 protein as during processing for preservation, increases cholesterol efflux from spermatozoa. The efflux of sperm membrane cholesterol and disturbance in cholesterol:phospholipids ratio causes destabilization of plasma membrane thereby inducing cryoinjury to the sperm. In this review, the biochemical, functional properties of PDC-109 protein and its role during semen cryopreservation is summarized. Copyright © 2013 Elsevier B.V. All rights reserved.

Cerebral Developmental Abnormalities in a Mouse with Systemic Pyruvate Dehydrogenase Deficiency

PubMed Central

Pliss, Lioudmila; Hausknecht, Kathryn A.; Stachowiak, Michal K.; Dlugos, Cynthia A.; Richards, Jerry B.; Patel, Mulchand S.

2013-01-01

Pyruvate dehydrogenase (PDH) complex (PDC) deficiency is an inborn error of pyruvate metabolism causing a variety of neurologic manifestations. Systematic analyses of development of affected brain structures and the cellular processes responsible for their impairment have not been performed due to the lack of an animal model for PDC deficiency. METHODS: In the present study we investigated a murine model of systemic PDC deficiency by interrupting the X-linked Pdha1 gene encoding the α subunit of PDH to study its role on brain development and behavioral studies. RESULTS: Male embryos died prenatally but heterozygous females were born. PDC activity was reduced in the brain and other tissues in female progeny compared to age-matched control females. Immunohistochemical analysis of several brain regions showed that approximately 40% of cells were PDH−. The oxidation of glucose to CO2 and incorporation of glucose-carbon into fatty acids were reduced in brain slices from 15 day-old PDC-deficient females. Histological analyses showed alterations in several structures in white and gray matters in 35 day-old PDC-deficient females. Reduction in total cell number and reduced dendritic arbors in Purkinje neurons were observed in PDC-deficient females. Furthermore, cell proliferation, migration and differentiation into neurons by newly generated cells were reduced in the affected females during pre- and postnatal periods. PDC-deficient mice had normal locomotor activity in a novel environment but displayed decreased startle responses to loud noises and there was evidence of abnormal pre-pulse inhibition of the startle reflex. CONCLUSIONS: The results show that a reduction in glucose metabolism resulting in deficit in energy production and fatty acid biosynthesis impairs cellular differentiation and brain development in PDC-deficient mice. PMID:23840713

The major protein of bovine seminal plasma, PDC-109, is a molecular chaperone.

PubMed

Sankhala, Rajeshwer Singh; Swamy, Musti J

2010-05-11

The major protein of bovine seminal plasma, PDC-109, binds to choline phospholipids on the sperm plasma membrane and induces the efflux of cholesterol and choline phospholipids, which is an important step in sperm capacitation. The high abundance, polydisperse nature and reversibility of thermal unfolding of PDC-109 suggest significant similarities to chaperone-like proteins such as spectrin, alpha-crystallin, and alpha-synuclein. In the present study, biochemical and biophysical approaches were employed to investigate the chaperone-like activity of PDC-109. The effect of various stress factors such as high temperature, chemical denaturant (urea), and acidic pH on target proteins such as lactate dehydrogenase, alcohol dehydrogenase, and insulin were studied in both the presence and absence of PDC-109. The results obtained indicate that PDC-109 exhibits chaperone-like activity, as evidenced by its ability to suppress the nonspecific aggregation of target proteins and direct them into productive folding. Atomic force microscopic studies demonstrate that PDC-109 effectively prevents the fibrillation of insulin, which is of considerable significance since amyloidogenesis has been reported to be a serious problem during sperm maturation in certain species. Binding of phosphorylcholine or high ionic strength in the medium inhibited the chaperone-like activity of PDC-109, suggesting that most likely the aggregation state of the protein is important for the chaperone function. These observations show that PDC-109 functions as a molecular chaperone in vitro, suggesting that it may assist the proper folding of proteins involved in the bovine sperm capacitation pathway. To the best of our knowledge, this is the first study reporting chaperone-like activity of a seminal plasma protein.

Critical Role of Plasmacytoid Dendritic Cells in Regulating Gene Expression and Innate Immune Responses to Human Rhinovirus-16

PubMed Central

Xi, Yang; Troy, Niamh M.; Anderson, Denise; Pena, Olga M.; Lynch, Jason P.; Phipps, Simon; Bosco, Anthony; Upham, John W.

2017-01-01

Though human rhinoviruses (HRVs) are usually innocuous viruses, they can trigger serious consequences in certain individuals, especially in the setting of impaired interferon (IFN) synthesis. Plasmacytoid dendritic cells (pDCs) are key IFN producing cells, though we know little about the role of pDC in HRV-induced immune responses. Herein, we used gene expression microarrays to examine HRV-activated peripheral blood mononuclear cells (PBMCs) from healthy people, in combination with pDC depletion, to assess whether observed gene expression patterns were pDC dependent. As expected, pDC depletion led to a major reduction in IFN-α release. This was associated with profound differences in gene expression between intact PBMC and pDC-depleted PBMC, and major changes in upstream regulators: 70–80% of the HRV activated genes appeared to be pDC dependent. Real-time PCR confirmed key changes in gene expression, in which the following selected genes were shown to be highly pDC dependent: the transcription factor IRF7, both IL-27 chains (IL-27p28 and EBI3), the alpha chain of the IL-15 receptor (IL-15RA) and the IFN-related gene IFI27. HRV-induced IL-6, IFN-γ, and IL-27 protein synthesis were also highly pDC dependent. Supplementing pDC-depleted cultures with recombinant IL-15, IFN-γ, IL-27, or IL-6 was able to restore the IFN-α response, thereby compensating for the absence of pDC. Though pDC comprise only a minority population of migratory leukocytes, our findings highlight the profound extent to which these cells contribute to the immune response to HRV. PMID:29118754

Pre-Departure Clearance (PDC): An Analysis of Aviation Safety Reporting System Reports Concerning PDC Related Errors

NASA Technical Reports Server (NTRS)

Montalyo, Michael L.; Lebacqz, J. Victor (Technical Monitor)

1994-01-01

Airlines operating in the United States are required to operate under instrument flight rules (EFR). Typically, a clearance is issued via voice transmission from clearance delivery at the departing airport. In 1990, the Federal Aviation Administration (FAA) began deployment of the Pre-Departure Clearance (PDC) system at 30 U.S. airports. The PDC system utilizes aeronautical datalink and Aircraft Communication and Reporting System (ACARS) to transmit departure clearances directly to the pilot. An objective of the PDC system is to provide an immediate reduction in voice congestion over the clearance delivery frequency. Participating airports report that this objective has been met. However, preliminary analysis of 42 Aviation Safety Reporting System (ASRS) reports has revealed problems in PDC procedures and formatting which have caused errors in the proper execution of the clearance. It must be acknowledged that this technology, along with other advancements on the flightdeck, is adding more responsibility to the crew and increasing the opportunity for error. The present study uses these findings as a basis for further coding and analysis of an additional 82 reports obtained from an ASRS database search. These reports indicate that clearances are often amended or exceptions are added in order to accommodate local ATC facilities. However, the onboard ACARS is limited in its ability to emphasize or highlight these changes which has resulted in altitude and heading deviations along with increases in ATC workload. Furthermore, few participating airports require any type of PDC receipt confirmation. In fact, 35% of all ASRS reports dealing with PDC's include failure to acquire the PDC at all. Consequently, this study examines pilots' suggestions contained in ASRS reports in order to develop recommendations to airlines and ATC facilities to help reduce the amount of incidents that occur.

Beneficial effect of feeding a ketogenic diet to mothers on brain development in their progeny with a murine model of pyruvate dehydrogenase complex deficiency.

PubMed

Pliss, Lioudmila; Jatania, Urvi; Patel, Mulchand S

2016-06-01

Pyruvate dehydrogenase complex (PDC) deficiency is a major inborn error of oxidative metabolism of pyruvate in the mitochondria causing congenital lactic acidosis and primarily structural and functional abnormalities of the central nervous system. To provide an alternate source of acetyl-CoA derived from ketone bodies to the developing brain, a formula high in fat content is widely employed as a treatment. In the present study we investigated efficacy of a high-fat diet given to mothers during pregnancy and lactation on lessening of the impact of PDC deficiency on brain development in PDC-deficient female progeny. A murine model of systemic PDC deficiency by interrupting the X-linked Pdha1 gene was employed in this study. Maternal consumption of a high-fat diet during pregnancy and lactation had no effect on number of live-birth, body growth, tissue PDC activity levels, as well as the in vitro rates of glucose oxidation and fatty acid biosynthesis by the developing brain of PDC-deficient female offspring during the postnatal age 35 days, as compared to the PDC-deficient progeny born to dams on a chow diet. Interestingly, brain weight was normalized in PDC-deficient progeny of high fat-fed mothers with improvement in impairment in brain structure deficit whereas brain weight was significantly decreased and was associated with greater cerebral structural defects in progeny of chow-fed mothers as compared to control progeny of mothers fed either a chow or high fat diet. The findings provide for the first time experimental support for beneficial effects of a ketogenic diet during the prenatal and early postnatal periods on the brain development of PDC-deficient mammalian progeny.

Fast, safe, and reliable methods for extraction of major inorganic cations from small quantities of woody plant tissues

Treesearch

Rakesh Minocha; Walter C. Shortle

1993-01-01

Two simple and fast methods for the extraction of major inorganic cations (Ca, Mg, Mn, K) from small quantities of stemwood and needles of woody plants were developed. A 3.2- or 6.4-mm cobalt drill bit was used to shave samples from disks and increment cores of stemwood. For ion extraction, wood (ground or shavings) or needles were either homogenzied using a Tekmar...

A Novel Coordination Polymer Constructed by Hetero-Metal Ions and 2,3-Pyridine Dicarboxylic Acid: Synthesis and Structure of [NiNa2(PDC)2(μ-H2O)(H2O)2] n

NASA Astrophysics Data System (ADS)

Dou, Ming-Yu; Lu, Jing

2017-12-01

A novel coordination polymer containing hetero-metal ions, [NiNa2(PDC)2(μ-H2O)(H2O)2] n , where PDC is 2,3-pyridine dicarboxylate ion, has been synthesized. In the structure, the PDC ligand chelates and bridges two Ni(II) and two Na(I) centers. Two kinds of metal centers are connected by μ4-PDC and μ2-H2O to form 2D coordination layers. Hydrogen bonds between coordination water molecules and carboxylate oxygen atoms further link these 2D coordination layers to form 3D supramolecular network.

A new scientific drilling infrastructure in Sweden

NASA Astrophysics Data System (ADS)

Rosberg, J.-E.; Lorenz, H.

2012-04-01

A new scientific drilling infrastructure is currently under commissioning at Lund University in southern Sweden and is intended primarily for Swedish scientific drilling projects. However, it will be available to the scientific community and even industry when not occupied. The drill rig, a crawler mounted Atlas Copco CT20, was funded by the Swedish Research Council (VR) after an application by the Swedish scientific drilling community under the lead of Prof. Leif Bjelm, Lund University. As a national resource it is, together with support of the Swedish Deep Drilling Program (SDDP) and the Swedish membership in ICDP, part of VR's commitment to scientific drilling. The Atlas Copco CT20 is a top modern, versatile diamond wireline core-drilling rig which can handle P, H and N sizes. It can operate on very small drill sites (500-800 m2) and, thus, leaves a minimal environmental footprint. The crawler makes the rig ideal for operations in remote locations. A total of only 3-4 truckloads is necessary for mobilization of the basic drilling equipment. Main technical specifications are: Depth capacity coring, based on vertical water filled hole: P-size to around 1050 m, hole size 123 mm and core size 85 mm. H-size to around 1600 m, hole size 96 mm and core size 63 mm. N-size to around 2500 m, hole size 76 mm and core size 48 mm. Weight: Complete rig including crawler, wet - 23500 kg Dimensions in (length, width, height) transport position: 11560 x 2500 x 3750 mm. Available in-hole equipment: Complete core retrieval system for PQ, HQ and NQ-sizes, including PHD, HRQ (V-Wall) and NRQ (V-Wall) drill rods covering the maximum drilling depth for each size (see rig depth capacity above). Both dual and triple tube for HQ and NQ-sizes. Casing advancers (PW, HW, NW and BW). Casing PWT, HWT, NW and BW. Bits and reamers. Additional equipment: Mud cleaning and mixing system. MWD-system (Measurements While Drilling). Cementing equipment. Fishing tools (Bowen Spear). Blow Out Preventer (BOP). Deviation tools. Wireline packers. And more.

Genetic modifications and introduction of heterologous pdc genes in Enterococcus faecalis for its use in production of bioethanol.

PubMed

Rana, N F; Gente, S; Rincé, A; Auffray, Y; Laplace, J M

2012-09-01

Genetically-modified Enterococcus faecalis has a potential of survival and can be used in ethanolic fermentations. Fermentation profiles of E. faecalis JH2-2 were assessed using glucose and lactose as carbon sources. Deletion of lactate dehydrogenase (ldh) genes increased the ethanol production from 0.25 to 0.82 g/l, which was further increased to 0.96 g/l by the insertion of a pyruvate decarboxylase (pdc) gene (from Sarcina ventriculi or Clostridium acetobutylicum) in place ldh1. When grown on lactose, the pdcSv and pdcCa showed 13.6 and 17.6 U mg(-1) of pdc specific activity, respectively. Highest activity (47 U mg(-1)) and ethanol concentration (2.3 g/l) were obtained with pdcCa using an expression plasmid. Formate and acetate were also produced in high quantities. Transcriptional analysis showed that aldehyde alcohol dehydrogenase gene was upregulated up to 16-fold. Further optimizations are required for higher ethanol production.

Nitrative Stress and Tau Accumulation in Amyotrophic Lateral Sclerosis/Parkinsonism-Dementia Complex (ALS/PDC) in the Kii Peninsula, Japan

PubMed Central

Hata, Yukiko; Ma, Ning; Yoneda, Misao; Morimoto, Satoru; Okano, Hideyuki; Murayama, Shigeo; Kawanishi, Shosuke; Kuzuhara, Shigeki; Kokubo, Yasumasa

2018-01-01

Objective: The Kii Peninsula of Japan is known to be a high incidence area of amyotrophic lateral sclerosis/parkinsonism-dementia complex (Kii ALS/PDC) with tauopathy. Nitrative stress and oxidative stress on ALS/PDC and their relationship to tau pathology were clarified. Methods: Seven patients with Kii ALS/PDC (3 males and 4 females, average age 70.7 years, 3 with ALS, 2 with ALS with dementia, and 2 with PDC) were analyzed in this study. Five patients with Alzheimer's disease and five normal aged subjects were used as controls. Immunohistochemical analysis was performed on formalin-fixed, paraffin-embedded temporal lobe sections (the hippocampal area including hippocampus, prosubiculum, subiculum, presubiculum, and parahippocampal gyri) using antibodies to detect phosphorylated tau (anti-AT-8), nitrated guanine (anti-8-NG), anti-iNOS, anti-NFκB, and oxidized guanine (anti-8-OHdG) antibodies. Results: Most hippocampal neurons of Kii ALS/PDC patients were stained with anti-8-NG, anti-iNOS, anti-NFκB, and anti-8-OHdG antibodies and some AT-8 positive neurons were co-stained with anti-8-NG antibody. The numbers of 8-NG positive neurons and 8-OHdG positive neurons were greater than AT-8 positive neurons and the number of 8-NG positive neurons was larger in patients with Kii ALS/PDC than in controls. Conclusion: Nitrative and oxidative stress may take priority over tau accumulation and lead to the neurodegeneration in Kii ALS/PDC. PMID:29403345

Ethylene-responsive transcription factors interact with promoters of ADH and PDC involved in persimmon (Diospyros kaki) fruit de-astringency

PubMed Central

Min, Ting; Yin, Xue-ren; Chen, Kun-song

2012-01-01

The persimmon fruit is a particularly good model for studying fruit response to hypoxia, in particular, the hypoxia-response ERF (HRE) genes. An anaerobic environment reduces fruit astringency by converting soluble condensed tannins (SCTs) into an insoluble form. Although the physiology of de-astringency has been widely studied, its molecular control is poorly understood. Both CO2 and ethylene treatments efficiently removed the astringency from ‘Mopan’ persimmon fruit, as indicated by a decrease in SCTs. Acetaldehyde, the putative agent for causing de-astringency, accumulated during these treatments, as did activities of the key enzymes of acetaldehyde synthesis, alcohol dehydrogenase (ADH), and pyruvate decarboxylase (PDC). Eight DkADH and DkPDC genes were isolated, and three candidates for a role in de-astringency, DkADH1, DkPDC1, and DkPDC2, were characterized by transcriptional analysis in different tissues. The significance of these specific isoforms was confirmed by principal component analysis. Transient expression in leaf tissue showed that DkPDC2 decreased SCTs. Interactions of six hypoxia-responsive ERF genes and target promoters were tested in transient assays. The results indicated that two hypoxia-responsive ERF genes, DkERF9 and DkERF10, were involved in separately regulating the DkPDC2 and DkADH1 promoters. It is proposed that a DkERF–DkADH/DkPDC cascade is involved in regulating persimmon de-astringency. PMID:23095993

Identification of HLA-A2–restricted CD8+ Cytotoxic T Cell Responses in Primary Biliary Cirrhosis

PubMed Central

Kita, Hiroto; Lian, Zhe-Xiong; Van de Water, Judy; He, Xiao-Song; Matsumura, Shuji; Kaplan, Marshall; Luketic, Velimir; Coppel, Ross L.; Ansari, Aftab A.; Gershwin, M. Eric

2002-01-01

Primary biliary cirrhosis (PBC) is characterized by an intense biliary inflammatory CD4+ and CD8+ T cell response. Very limited information on autoantigen-specific cytotoxic T lymphocyte (CTL) responses is available compared with autoreactive CD4+ T cell responses. Using peripheral blood mononuclear cells (PBMCs) from PBC, we identified an HLA-A2–restricted CTL epitope of the E2 component of pyruvate dehydrogenase (PDC-E2), the immunodominant mitochondrial autoantigen. This peptide, amino acids 159–167 of PDC-E2, induces specific MHC class I–restricted CD8+ CTL lines from 10/12 HLA-A2+ PBC patients, but not controls, after in vitro stimulation with antigen-pulsed dendritic cells (DCs). PDC-E2–specific CTLs could also be generated by pulsing DCs with full-length recombinant PDC-E2 protein. Furthermore, using soluble PDC-E2 complexed with either PDC-E2–specific human monoclonal antibody or affinity-purified autoantibodies against PDC-E2, the generation of PDC-E2–specific CTLs, occurred at 100-fold and 10-fold less concentration, respectively, compared with soluble antigen alone. Collectively, these data demonstrate that autoantibody, helper, and CTL epitopes all contain a shared peptide sequence. The finding that autoantigen–immune complexes can not only cross-present but also that presentation of the autoantigen is of a higher relative efficiency, for the first time defines a unique role for autoantibodies in the pathogenesis of an autoimmune disease. PMID:11781370

Nitrative Stress and Tau Accumulation in Amyotrophic Lateral Sclerosis/Parkinsonism-Dementia Complex (ALS/PDC) in the Kii Peninsula, Japan.

PubMed

Hata, Yukiko; Ma, Ning; Yoneda, Misao; Morimoto, Satoru; Okano, Hideyuki; Murayama, Shigeo; Kawanishi, Shosuke; Kuzuhara, Shigeki; Kokubo, Yasumasa

2017-01-01

Objective: The Kii Peninsula of Japan is known to be a high incidence area of amyotrophic lateral sclerosis/parkinsonism-dementia complex (Kii ALS/PDC) with tauopathy. Nitrative stress and oxidative stress on ALS/PDC and their relationship to tau pathology were clarified. Methods: Seven patients with Kii ALS/PDC (3 males and 4 females, average age 70.7 years, 3 with ALS, 2 with ALS with dementia, and 2 with PDC) were analyzed in this study. Five patients with Alzheimer's disease and five normal aged subjects were used as controls. Immunohistochemical analysis was performed on formalin-fixed, paraffin-embedded temporal lobe sections (the hippocampal area including hippocampus, prosubiculum, subiculum, presubiculum, and parahippocampal gyri) using antibodies to detect phosphorylated tau (anti-AT-8), nitrated guanine (anti-8-NG), anti-iNOS, anti-NFκB, and oxidized guanine (anti-8-OHdG) antibodies. Results: Most hippocampal neurons of Kii ALS/PDC patients were stained with anti-8-NG, anti-iNOS, anti-NFκB, and anti-8-OHdG antibodies and some AT-8 positive neurons were co-stained with anti-8-NG antibody. The numbers of 8-NG positive neurons and 8-OHdG positive neurons were greater than AT-8 positive neurons and the number of 8-NG positive neurons was larger in patients with Kii ALS/PDC than in controls. Conclusion: Nitrative and oxidative stress may take priority over tau accumulation and lead to the neurodegeneration in Kii ALS/PDC.

Flexible shaft and roof drilling system

DOEpatents

Blanz, John H.

1981-01-01

A system for drilling holes in the roof of a mine has a flexible shaft with a pair of oppositely wound, coaxial flat bands. One of the flat bands defines an inner spring that is wound right handed into a helical configuration, adjacent convolutions being in nesting relationship to one another. The other flat band defines an outer spring that is wound left handed into a helical configuration about the inner band, adjacent convolutions being nesting relationship with one another. A transition member that is configured to hold a rock bit is mounted to one end of the flexible shaft. When torque and thrust are applied to the flexible shaft by a driver, the inner spring expands outwardly and the outer spring contracts inwardly to form a relatively rigid shaft.

Parabolic Dish Concentrator (PDC-2) Development

NASA Technical Reports Server (NTRS)

Rafinejad, D.

1984-01-01

The design of the Parabolic Dish Concentrator (PDC-2) is described. The following five subsystems of the concentrator are discussed: (1) reflective surface subsystem, (2) support structure subsystem, (3) foundation, (4) drive subsystem, and (5) electrical and control subsystem. The status of the PDC-2 development project is assessed.

Combining conventional and thermal drilling in order to increase speed and reduce costs of drilling operations to access deep geothermal resources

NASA Astrophysics Data System (ADS)

Rossi, Edoardo; Kant, Michael A.; von Rohr, Philipp Rudolf; Saar, Martin O.

2017-04-01

The exploitation of deep geothermal resources for energy production relies on finding cost effective solutions to increase the drilling performance in hard rocks. Conventional rotary drilling techniques, based on mechanical rock exportation, result in high rates of drilling tool wearing, causing significant costs. Additionally, rotary drilling results in low drilling speeds in the typically hard crystalline basement rocks targeted for enhanced geothermal energy utilization technologies. Furthermore, even lower overall drilling rates result, when considering tripping times required to exchange worn drill tools. Therefore, alternative drilling techniques, such as hammering, thermal drilling, plasma drilling, and jetting processes are widely investigated in order to provide cost-effective alternatives to conventional drilling methods. A promising approach, that combines conventional rotary and thermal drilling techniques, is investigated in the present work. Here, the rock material is thermally weakened before being exported by conventional cutters. Heat is locally provided by a flame, which moves over the rock surface, heat-treating the material. Besides reducing the rock strength, an in-depth smoothening effect of the mechanical rock properties is observed due to the thermal treatment. This results in reduced rates of drill bit wearing and higher rates of penetration, which in turn decreases drilling costs significantly, particularly for deep-drilling projects. Due to the high heating rates, rock-hardening, commonly observed at moderate temperatures, can be avoided. The flame action can be modelled as a localized, high heat transfer coefficient flame treatment, which results in orders of magnitude higher heating rates than conventional oven treatments. Therefore, we analyse rock strength variations after different maximum temperatures, flame-based heating rates, and rock confinement pressures. The results show that flame treatments lead to a monotonous decrease of rock strength with temperature. This is different from oven treatments, where an initial increase of strength is typically observed, followed by a steep decrease upon further (slow) oven-heating. Thus, the weakening of sandstone and granite samples due to flame treatments indicates the feasibility of a combined mechanical-thermal drilling system. These results suggest that the new combined method enables improved rates of penetration in hard rocks while reducing the rate of drill tool wear. We also present possible implementations of this combined drilling system in the field. From field test results, advantages and limitations of the proposed new technology are presented, with an emphasis on accessing geothermal energy resources in crystalline basement rocks.

Hydraulics calculation in drilling simulator

NASA Astrophysics Data System (ADS)

Malyugin, Aleksey A.; Kazunin, Dmitry V.

2018-05-01

The modeling of drilling hydraulics in the simulator system is discussed. This model is based on the previously developed quasi-steady model of an incompressible fluid flow. The model simulates the operation of all parts of the hydraulic drilling system. Based on the principles of creating a common hydraulic model, a set of new elements for well hydraulics was developed. It includes elements that correspond to the in-drillstring and annular space. There are elements controlling the inflow from the reservoir into the well and simulating the lift of gas along the annulus. New elements of the hydrosystem take into account the changing geometry of the well, loss in the bit, characteristics of the fluids including viscoplasticity. There is an opportunity specify the complications, the main one of which is gas, oil and water inflow. Correct work of models in cases of complications makes it possible to work out various methods for their elimination. The coefficients of the model are adjusted on the basis of incomplete experimental data provided by operators of drilling platforms. At the end of the article the results of modeling the elimination of gas inflow by a continuous method are presented. The values displayed in the simulator (drill pipe pressure, annulus pressure, input and output flow rates) are in good agreement with the experimental data. This exercise took one hour, which is less than the time on a real rig with the same configuration of equipment and well.

OPTIMIZATION OF MUD HAMMER DRILLING PERFORMANCE - A PROGRAM TO BENCHMARK THE VIABILITY OF ADVANCED MUD HAMMER DRILLING

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

Arnis Judzis

2003-07-01

This document details the progress to date on the ''OPTIMIZATION OF MUD HAMMER DRILLING PERFORMANCE--A PROGRAM TO BENCHMARK THE VIABILITY OF ADVANCED MUD HAMMER DRILLING'' contract for the quarter starting April 2003 through June 2003. The DOE and TerraTek continue to wait for Novatek on the optimization portion of the testing program (they are completely rebuilding their fluid hammer). Accomplishments included the following: (1) Hughes Christensen has recently expressed interest in the possibility of a program to examine cutter impact testing, which would be useful in a better understanding of the physics of rock impact. Their interest however is notmore » necessarily fluid hammers, but to use the information for drilling bit development. (2) Novatek (cost sharing supplier of tools) has informed the DOE project manager that their tool may not be ready for ''optimization'' testing late summer 2003 (August-September timeframe) as originally anticipated. During 3Q Novatek plans to meet with TerraTek to discuss progress with their tool for 4Q 2003 testing. (3) A task for an addendum to the hammer project related to cutter impact studies was written during 2Q 2003. (4) Smith International internally is upgrading their hammer for the optimization testing phase. One currently known area of improvement is their development program to significantly increase the hammer blow energy.« less

Estimating time-varying drug adherence using electronic records: extending the proportion of days covered (PDC) method.

PubMed

Bijlsma, Maarten J; Janssen, Fanny; Hak, Eelko

2016-03-01

Accurate measurement of drug adherence is essential for valid risk-benefit assessments of pharmacologic interventions. To date, measures of drug adherence have almost exclusively been applied for a fixed-time interval and without considering changes over time. However, patients with irregular dosing behaviour commonly have a different prognosis than patients with stable dosing behaviour. We propose a method, based on the proportion of days covered (PDC) method, to measure time-varying drug adherence and drug dosage using electronic records. We compare a time-fixed PDC method with the time-varying PDC method through detailed examples and through summary statistics of 100 randomly selected patients on statin therapy. We demonstrate that time-varying PDC method better distinguishes an irregularly dosing patient from a stably dosing patient and demonstrate how the time-fixed method can result in a biassed estimate of drug adherence. Furthermore, the time-varying PDC method may be better used to reduce certain types of confounding and misclassification of exposure. The time-varying PDC method may improve longitudinal and time-to-event studies that associate adherence with a clinical outcome or (intervention) studies that seek to describe changes in adherence over time. Copyright © 2015 John Wiley & Sons, Ltd.

Biophysical investigations on the interaction of the major bovine seminal plasma protein, PDC-109, with heparin.

PubMed

Sankhala, Rajeshwer S; Damai, Rajani S; Anbazhagan, V; Kumar, C Sudheer; Bulusu, Gopalakrishnan; Swamy, Musti J

2011-11-10

PDC-109, the major bovine seminal plasma protein, binds to sperm plasma membrane and modulates capacitation in the presence of heparin. In view of this, the PDC-109/heparin interaction has been investigated employing various biophysical approaches. Isothermal titration calorimetric studies yielded the association constant and changes in enthalpy and entropy for the interaction at 25 °C (pH 7.4) as 1.92 (±0.2) × 10(5) M(-1), 18.6 (±1.6) kcal M(-1), and 86.5 (±5.1) cal M(-1) K(-1), respectively, whereas differential scanning calorimetric studies indicated that heparin binding results in a significant increase in the thermal stability of PDC-109. The affinity decreases with increase in pH and ionic strength, consistent with the involvement of electrostatic forces in this interaction. Circular dichroism spectroscopic studies indicated that PDC-109 retains its conformational features even up to 70-75 °C in the presence of heparin, whereas the native protein unfolds at about 55 °C. Atomic force microscopic studies demonstrated that large oligomeric structures are formed upon binding of PDC-109 to heparin, indicating an increase in the local density of the protein, which may be relevant to the ability of heparin to potentiate PDC-109 induced sperm capacitation.

Spermine and spermidine act as chemical chaperones and enhance chaperone-like and membranolytic activities of major bovine seminal plasma protein, PDC-109.

PubMed

Singh, Bhanu Pratap; Saha, Ishita; Nandi, Indrani; Swamy, Musti J

2017-12-02

The major bovine seminal plasma protein, PDC-109, binds to choline phospholipids of the sperm plasma membrane and induces an efflux of cholesterol and choline phospholipids (cholesterol efflux), which is crucial for sperm capacitation. PDC-109 also exhibits chaperone-like activity and protects target proteins against various kinds of stress. Here we show that the polyamines spermine and spermidine, present in high concentration in the seminal plasma of various mammals, increase the ability of PDC-109 to perturb membrane structure as well as its chaperone-like activity. Interestingly, spermine/spermidine alone did not perturb membrane structure but exhibited chaperone-like activity by protecting target proteins against thermal and oxidative stress. When spermine/spermidine was used along with PDC-109, the observed chaperone-like activity was considerably higher than that expected for a simple additive effect, suggesting that PDC-109 and the polyamines act in a synergistic fashion. These results indicate that at the high concentrations present in the seminal plasma spermine/spermidine exhibit a positive modulatory effect on the chaperone-like activity of PDC-109 and may also function as chemical chaperones and protect other seminal plasma proteins from various kinds of stress. Copyright © 2017 Elsevier Inc. All rights reserved.

Isolation and characterization of cDNA clones for carrot extensin and a proline-rich 33-kDa protein

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

Chen, J.; Varner, J.E.

1985-07-01

Extensins are hydroxyproline-rich glycoproteins associated with most dicotyledonous plant cell walls. To isolate cDNA clones encoding extensin, the authors started by isolating poly(A) RNA from carrot root tissue, and then translating the RNA in vitro, in the presence of tritiated leucine or proline. A 33-kDa peptide was identified in the translation products as a putative extensin precursor. From a cDNA library constructed with poly(A) RNA from wounded carrots, one cDNA clone (pDC5) was identified that specifically hybridized to poly(A) RNA encoding this 33-kDa peptide. They isolated three cDNA clones (pDC11, pDC12, and pDC16) from another cDNA library using pCD5 asmore » a probe. DNA sequence data, RNA hybridization analysis, and hybrid released in vitro translation indicate that the cDNA clones pDC11 encodes extensin and that cDNA clones pDC12 and pDC16 encode the 33-kDa peptide, which as yet has an unknown identity and function. The assumption that the 33-kDa peptide was an extensin precursor was invalid. RNA hybridization analysis showed that RNA encoded by both clone types is accumulated upon wounding.« less

An internal deletion in MTH1 enables growth on glucose of pyruvate-decarboxylase negative, non-fermentative Saccharomyces cerevisiae

PubMed Central

2012-01-01

Background Pyruvate-decarboxylase negative (Pdc-) strains of Saccharomyces cerevisiae combine the robustness and high glycolytic capacity of this yeast with the absence of alcoholic fermentation. This makes Pdc-S. cerevisiae an interesting platform for efficient conversion of glucose towards pyruvate-derived products without formation of ethanol as a by-product. However, Pdc- strains cannot grow on high glucose concentrations and require C2-compounds (ethanol or acetate) for growth under conditions with low glucose concentrations, which hitherto has limited application in industry. Results Genetic analysis of a Pdc- strain previously evolved to overcome these deficiencies revealed a 225bp in-frame internal deletion in MTH1, encoding a transcriptional regulator involved in glucose sensing. This internal deletion contains a phosphorylation site required for degradation, thereby hypothetically resulting in increased stability of the protein. Reverse engineering of this alternative MTH1 allele into a non-evolved Pdc- strain enabled growth on 20 g l-1 glucose and 0.3% (v/v) ethanol at a maximum specific growth rate (0.24 h-1) similar to that of the evolved Pdc- strain (0.23 h-1). Furthermore, the reverse engineered Pdc- strain grew on glucose as sole carbon source, albeit at a lower specific growth rate (0.10 h-1) than the evolved strain (0.20 h-1). The observation that overexpression of the wild-type MTH1 allele also restored growth of Pdc-S. cerevisiae on glucose is consistent with the hypothesis that the internal deletion results in decreased degradation of Mth1. Reduced degradation of Mth1 has been shown to result in deregulation of hexose transport. In Pdc- strains, reduced glucose uptake may prevent intracellular accumulation of pyruvate and/or redox problems, while release of glucose repression due to the MTH1 internal deletion may contribute to alleviation of the C2-compound auxotrophy. Conclusions In this study we have discovered and characterised a mutation in MTH1 enabling Pdc- strains to grow on glucose as the sole carbon source. This successful example of reverse engineering not only increases the understanding of the glucose tolerance of evolved Pdc-S. cerevisiae, but also allows introduction of this portable genetic element into various industrial yeast strains, thereby simplifying metabolic engineering strategies. PMID:22978798

Ultrasonic/Sonic Driller/Corer (USDC) as a Subsurface Sampler and Sensors Platform for Planetary Exploration Applications

NASA Technical Reports Server (NTRS)

Bar-Cohen, Yoseph; Sherrit, Stewart; Bao, Xiaoqi; Badescu, Mircea; Aldrich, Jack; Chang, Zensheu

2006-01-01

The search for existing or past life in the Universe is one of the most important objectives of NASA's mission. For this purpose, effective instruments that can sample and conduct in-situ astrobiology analysis are being developed. In support of this objective, a series of novel mechanisms that are driven by an Ultrasonic/Sonic actuator have been developed to probe and sample rocks, ice and soil. This mechanism is driven by an ultrasonic piezoelectric actuator that impacts a bit at sonic frequencies through the use of an intermediate free-mass. Ultrasonic/Sonic Driller/Corer (USDC) devices were made that can produce both core and powdered cuttings, operate as a sounder to emit elastic waves and serve as a platform for sensors. For planetary exploration, this mechanism has the important advantage of requiring low axial force, virtually no torque, and can be duty cycled for operation at low average power. The advantage of requiring low axial load allows overcoming a major limitation of planetary sampling in low gravity environments or when operating from lightweight robots and rovers. The ability to operate at duty cycling with low average power produces a minimum temperature rise allowing for control of the sample integrity and preventing damage to potential biological markers in the acquired sample. The development of the USDC is being pursued on various fronts ranging from analytical modeling to mechanisms improvements while considering a wide range of potential applications. While developing the analytical capability to predict and optimize its performance, efforts are made to enhance its capability to drill at higher power and high speed. Taking advantage of the fact that the bit does not require rotation, sensors (e.g., thermocouple and fiberoptics) were integrated into the bit to examine the borehole during drilling. The sounding effect of the drill was used to emit elastic waves in order to evaluate the surface characteristics of rocks. Since the USDC is driven by piezoelectric actuation mechanism it can designed to operate at extreme temperature environments from very cold as on Titan and Europa to very hot as on Venus. In this paper, a review of the latest development and applications of the USDC will be given.

Insights into Proximal-Medial Pyroclastic Density Current Deposits at a High-Risk Glaciated Volcano: Mt Ruapehu, New Zealand

NASA Astrophysics Data System (ADS)

Cowlyn, J.; Kennedy, B.; Gravley, D. M.; Cronin, S. J.; Pardo, N.; Wilson, T. M.; Leonard, G.; Townsend, D.; Dufek, J.

2014-12-01

Pyroclastic density currents (PDCs) are a destructive volcanic hazard. Quantifying the types, frequency and magnitudes of PDC events in the geological record is essential for effective risk management. However small-medium volume valley-confined PDC deposits have low preservation potential, especially when emplaced in active drainages or onto snow or ice. Where PDC deposits are preserved they can be difficult to distinguish from other surficial deposits and are frequently misinterpreted or overlooked. This is the case at Mt. Ruapehu; a much visited, high-risk active volcano in New Zealand with no historical PDCs. Through systematic field observations we identified several young proximal-medial andesitic PDC deposits exposed on Ruapehu's eastern flanks. The oldest deposits (Ohinewairua PDCs, <13.6 ka) are massive pumice-rich deposits that are preserved at least 7km from source (North Crater) and correlate with Ruapehu's largest plinian eruptions. Overlying these, the pumice-rich Pourahu PDC deposit reaches >10km from source (South Crater) and correlates with Ruapehu's last known plinian eruption (~11.6 ka). Several younger locally preserved PDC deposits (Tukino PDCs) with denser juvenile clasts represent proximal PDCs from smaller eruptions at South Crater. Finally, a variably welded, bedded deposit containing clasts of welded spatter is interpreted to represent multiple failures of near-vent (North Ruapehu) accumulations of erupted material. Here, PDC initiation appears to have been controlled by the topographic gradient and deposition rate, without requiring a collapsing eruption column. The Ruapehu deposits highlight the limited preservation of PDC deposits, which appears to be favoured at PDC margins. Lateral and vertical flow stratification means the resulting deposits may not then represent the bulk flow. Additionally, deposit textures, distributions, and associations with moraines indicate that many of Ruapehu's PDCs encountered glacial ice during transport. This affected their distribution, mobility and preservation, and has implications for assessing the PDC hazard at Ruapehu and other glaciated volcanoes. The deposits reinforce that hazardous PDCs threatening life and infrastructure may be generated even from small eruptions and across a wide range of eruption styles.

Neuropsychological study of amyotrophic lateral sclerosis and parkinsonism-dementia complex in Kii peninsula, Japan

PubMed Central

2014-01-01

Background The Kii peninsula of Japan is one of the foci of amyotrophic lateral sclerosis and parkinsonism-dementia complex (ALS/PDC) in the world. The purpose of this study is to clarify the neuropsychological features of the patients with ALS/PDC of the Kii peninsula (Kii ALS/PDC). Methods The medical interview was done on 13 patients with Kii ALS/PDC, 12 patients with Alzheimer’s disease, 10 patients with progressive supranuclear palsy, 10 patients with frontotemporal lobar degeneration and 10 patients with dementia with Lewy bodies. These patients and their carer/spouse were asked to report any history of abulia-apathy, hallucination, personality change and other variety of symptoms. Patients also underwent brain magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT), and neuropsychological tests comprising the Mini Mental State Examination, Raven’s Colored Progressive Matrices, verbal fluency, and Paired-Associate Word Learning Test and some of them were assessed with the Frontal Assessment Battery (FAB). Results All patients with Kii ALS/PDC had cognitive dysfunction including abulia-apathy, bradyphrenia, hallucination, decrease of extraversion, disorientation, and delayed reaction time. Brain MRI showed atrophy of the frontal and/or temporal lobes, and SPECT revealed a decrease in cerebral blood flow of the frontal and/or temporal lobes in all patients with Kii ALS/PDC. Disorientation, difficulty in word recall, delayed reaction time, and low FAB score were recognized in Kii ALS/PDC patients with cognitive dysfunction. Conclusions The core neuropsychological features of the patients with Kii ALS/PDC were characterized by marked abulia-apathy, bradyphrenia, and hallucination. PMID:25041813

Minimally invasive fluoroscopic percutaneous peritoneal dialysis catheter salvage.

PubMed

Narayan, Rajeev; Fried, Terrance; Chica, Gerardo; Schaefer, Mathew; Mullins, Daniel

2014-06-01

Peritoneal dialysis catheter (PDC) dysfunction can often be treated fluoroscopically by manipulation with wire, balloon or stiff stylet, saving surgical intervention for refractory cases. We describe an enhanced percutaneous approach to PDC salvage that can lead to a more definitive intervention and salvage for cases refractory to fluoroscopic manipulation. In five cases of PD catheter malfunction, the deep cuff was dissected free after a 0.035 hydrophilic wire was passed into the peritoneum through the PDC. Only the intraperitoneal portion of the PDC was explanted. The PDC was cleared of obstruction and omentum. The intraperitoneal portion of the PDC was reimplanted over wire via a peel-away sheath and the deep cuff sutured. Omental entrapment was present in three of five patients and fibrin occlusion in four of the five cases. All catheters were repaired successfully by the described technique. Post procedure, 3-5 days of lower volume, recumbent PD exchanges were performed prior to full-dose PD. No perioperative complications or leaks were noted. All PDCs were patent at 6 months. One patient required laparoscopy for recurrent omental wrapping 3 months post intervention. PDC salvage in this manner is a cost-effective alternative to laparoscopic repair of PDCs failing catheter manipulation. The infection barrier afforded by the original superficial cuff and subcutaneous tunnel is maintained. PD can be resumed immediately. Only refractory cases need laparoscopy. This procedure allows for a more definitive correction of catheter migration and obstruction, avoids placement of a new PDC or temporary hemodialysis, is cost-effective and expands percutaneous options for dysfunctional PD catheters.

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

Gavignet, A.A.; Bradbury, L.J.; Quetier, F.P.

In current practice, the optimization of drilling hydraulics consists of the selection of nozzle sizes that maximize either jet impact or hydraulic power at the nozzle. But what is required for a real optimization is the knowledge of the hydraulic forces available for cleaning at the rock face, not at the nozzle. This paper shows the results of hot-wire anemometry experiments that provide insight into the flow distribution in a jet bit. Direct measurements of the flow field, including turbulence levels, are reported and discussed.

The Proliferation of PDC-Type Environments in Industry and Universities

NASA Technical Reports Server (NTRS)

Shishko, R.

2000-01-01

JPL's Project Design Cenger (PDC), opened in 1994, has become a model for other facilities of the same type in the aerospace industry. More recently, PDC-type environments have been adopted by some university aerospace departments as an educational tool. This paper discusses some of these facilities and their possible future direction.

Polymorphisms in the phosducin (PDC) gene on chromosome 1q25-32

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

Humphries, P.; Mansergh, F.C.; Farrar, G.J.

1994-09-01

Phosducin (33 kDa protein or MEKA) is a principal water-soluble phosphoprotein in the rod and cone photoreceptor cells and pinealocytes. This protein modulates the phototransduction cascade by binding to the beta and gamma subunit complexes of transducin. The PDC gene has been mapped to 1q25-32, the region of linkage of two hereditary retinal degenerative disorders; autosomal dominant juvenile-onset open-angle glaucoma and one form of autosomal recessive RP. Using previously published sequence data, PCR primers were designed to amplify the coding and 5{prime} flanking regions of the PDC gene. Direct sequencing revealed three polymorphisms in the 5{prime} flanking region, two ofmore » which were in regions highly homologous between humans and mice. Analysis of the polymorphisms was then extended to larger population samples using SSCPE and denaturing gel analysis. The first polymorphism PDC1 resulted from an insertion of a G residue at position -653/4. Allele frequencies were determined to be 0.51 (insG) and 0.49 (normal) giving a PIC value of 0.50. A deletion of a T residue at position -488 was the basis of the PDC2 polymorphism with allele frequencies of 0.88 (normal) and 0.12 (delT) and a PIC value of 0.21. Interestingly, the allele with an inserted G residue in PDC1 always segregrated with the deleted T allele in PDC2. The third polymorphism PDC3 was caused by a T or G residue at position -1083. Allele frequencies of 0.26 (G residue) and 0.74 (T residue) were determined from an analysis of 80 individuals with an overall PIC value of 0.39. The identification of these three polymorphisms in the PDC gene will be useful for future genetic linkage studies of chromosome 1q in inherited retinopathies.« less

Independent of plasmacytoid dendritic cell (pDC) infection, pDC triggered by virus-infected cells mount enhanced type I IFN responses of different composition as opposed to pDC stimulated with free virus.

PubMed

Frenz, Theresa; Graalmann, Lukas; Detje, Claudia N; Döring, Marius; Grabski, Elena; Scheu, Stefanie; Kalinke, Ulrich

2014-09-01

Upon treatment with vesicular stomatitis virus (VSV) particles, plasmacytoid dendritic cells (pDC) are triggered to mount substantial type I IFN responses, whereas myeloid DC (mDC) are only minor producers. Interestingly, bone marrow-derived (BM-)mDC were more vulnerable to infection with enhanced GFP (eGFP)-expressing VSV (VSVeGFP) than BM-pDC. BM-pDC stimulated with wild-type VSV mounted TLR-dependent IFN responses that were independent of RIG-I-like helicase (RLH) signaling. In contrast, in BM-pDC the VSV variant M2 induced particularly high IFN responses triggered in a TLR- and RLH-dependent manner, whereas BM-mDC stimulation was solely RLH-dependent. Importantly, VSVeGFP treatment of BM-pDC derived from IFN-β yellow fluorescent protein (YFP) reporter mice (messenger of IFN-β) resulted in YFP(+) and eGFP(+) single-positive cells, whereas among messenger of IFN-β-BM-mDC most YFP(+) cells were also eGFP(+). This observation indicated that unlike mDC, direct virus infection was not required to trigger IFN responses of pDC. VSV-infected BM-mDC triggered BM-pDC to mount significantly higher IFN responses than free virus particles. Stimulation with infected cells enhanced the percentages of pDC subsets expressing either IFN-β(+) or IFN-α6(+) plus IFN-β(+). Irrespective of whether stimulated with free virus or infected cells, IFN induction was dependent on autophagy of pDC, whereas autophagy of the infected mDC was dispensable. Collectively, these results indicated that productive VSV infection was needed to trigger IFN responses of mDC, but not of pDC, and that IFN responses were primarily induced by virus-infected cells that stimulated pDC in a TLR-dependent manner. Copyright © 2014 by The American Association of Immunologists, Inc.

Molecular recognition modes between adenine or adeniniun(1+) ion and binary M(II)(pdc) chelates (MCoZn; pdc=pyridine-2,6-dicarboxylate(2-) ion).

PubMed

Del Pilar Brandi-Blanco, María; Choquesillo-Lazarte, Duane; Domínguez-Martín, Alicia; Matilla-Hernández, Antonio; González-Pérez, Josefa María; Castiñeiras, Alfonso; Niclós-Gutiérrez, Juan

2013-10-01

Mixed ligand M(II)-complexes (MCoZn) with pyridine-2,6-dicarboxylate(2-) chelator (pdc) and adenine (Hade) have been synthesized and studied by X-ray diffraction and other spectral and thermal methods: [Cu(pdc)(H(N9)ade)(H2O)] (1), [Cu2(pdc)2(H2O)2(μ2-N3,N7-H(N9)ade)]·3H2O (2), trans-[M(pdc)(H(N9)ade)(H2O)2]·nH2O for MCo (3-L, 3-M, 3-H) or Zn (4-L, 4-H), where n is 0, 1 or 3 for the 'lowest' (L), 'medium' (M) and 'highest' (H) hydrated forms, and the salt trans-[Ni(pdc)(H2(N1,N9)ade)(H2O)2]Cl·2H2O (5). In all the nine compounds, both neutral and cationic adenine exist as their most stable tautomer and the molecular recognition pattern between the metal-pdc chelates and the adenine or adeninium(1+) ligands involves the MN7 bond in cooperation with an intra-molecular N6H⋯O(coordinated carboxylate) interligand interaction. In addition the dinuclear copper(II) compound (2) has the CuN3 bond and the N9H⋯O(coord. carboxylate) interaction. The structures of mononuclear ternary complexes proved that the molecular recognition pattern is the same irrespective of (a) the coordination geometry of the complex molecule, (b) the different hydrated forms of crystals with Co or Zn, and (c) the neutral of cationic form of the adenine ligand. These features are related to the mer-NO2 chelating ligand conformation (imposed by the planar rigidity of pdc) as a driving force for the observed metal binding mode. Copyright © 2013 Elsevier Inc. All rights reserved.

Random phage mimotopes recognized by monoclonal antibodies against the pyruvate dehydrogenase complex-E2 (PDC-E2).

PubMed Central

Cha, S; Leung, P S; Van de Water, J; Tsuneyama, K; Joplin, R E; Ansari, A A; Nakanuma, Y; Schatz, P J; Cwirla, S; Fabris, L E; Neuberger, J M; Gershwin, M E; Coppel, R L

1996-01-01

Dihydrolipoamide acetyltransferase, the E2 component of the pyruvate dehydrogenase complex (PDC-E2), is the autoantigen most commonly recognized by autoantibodies in primary biliary cirrhosis (PBC). We identified a peptide mimotope(s) of PDC-E2 by screening a phage-epitope library expressing random dodecapeptides in the pIII coat protein of fd phage using C355.1, a murine monoclonal antibody (mAb) that recognizes a conformation-dependent epitope in the inner lipoyl domain of PDC-E2 and uniquely stains the apical region of bile duct epithelium (BDE) only in patients with PBC. Eight different sequences were identified in 36 phage clones. WMSYPDRTLRTS was present in 29 clones; WESYPFRVGTSL, APKTYVSVSGMV, LTYVSLQGRQGH, LDYVPLKHRHRH, AALWGVKVRHVS, KVLNRIMAGVRH and GNVALVSSRVNA were singly represented. Three common amino acid motifs (W-SYP, TYVS, and VRH) were shared among all peptide sequences. Competitive inhibition of the immunohistochemical staining of PBC BDE was performed by incubating the peptides WMSYPDRTLRTS, WESYPDRTLRTS, APKTYVSVSGMV, and AALWGVKVRHVS with either C355.1 or a second PDC-E2-specific mAb, C150.1. Both mAbs were originally generated to PDC-E2 but map to distinct regions of PDC-E2. Two of the peptides, although selected by reaction with C355.1, strongly inhibited the staining of BDE by C150.1, whereas the peptide APKTYVSVSGMV consistently inhibited the staining of C355.1 on biliary duct epithelium more strongly than the typical mitochondrial staining of hepatocytes. Rabbit sera raised against the peptide WMSYPDRTLRTS stained BDE of livers and isolated bile duct epithelial cells of PBC patients more intensively than controls. The rabbit sera stained all size ducts in normals, but only small/medium-sized ductules in PBC livers. These studies provide evidence that the antigen present in BDE is a molecular mimic of PDC-E2, and not PDC-E2 itself. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8855289

Use of alternating and pulsed direct current electrified fields for zebra mussel control

USGS Publications Warehouse

Luoma, James A.; Dean, Jan C.; Severson, Todd J.; Wise, Jeremy K.; Barbour, Matthew

2017-01-01

Alternatives to chemicals for controlling dreissenid mussels are desirable for environmental compatibility, but few alternatives exist. Previous studies have evaluated the use of electrified fields for stunning and/or killing planktonic life stages of dreissenid mussels, however, the available literature on the use of electrified fields to control adult dreissenid mussels is limited. We evaluated the effects of sinusoidal alternating current (AC) and 20% duty cycle square-wave pulsed direct current (PDC) exposure on the survival of adult zebra mussels at water temperatures of 10, 15, and 22 °C. Peak voltage gradients of ~ 17 and 30 Vp/cm in the AC and PDC exposures, respectively, were continuously applied for 24, 48, or 72 h. Peak power densities ranged from 77,999 to 107,199 µW/cm3 in the AC exposures and 245,320 to 313,945 µW/cm3 in the PDC exposures. The peak dose ranged from 6,739 to 27,298 Joules/cm3 and 21,306 to 80,941 Joules/cm3 in the AC and PDC exposures, respectively. The applied power ranged from 16.6 to 68.9 kWh in the AC exposures and from 22.2 to 86.4 kWh in the PDC exposures. Mortality ranged from 2.7 to 92.7% in the AC exposed groups and from 24.0 to 98.7% in PDC exposed groups. Mortality increased with corresponding increases in water temperature and exposure duration, and we observed more zebra mussel mortality in the PDC exposures. Exposures conducted with AC required less of a peak dose (Joules/cm3) but more applied power (kWh) to achieve the same level of adult zebra mussel mortality as corresponding PDC exposures. The results demonstrate that 20% duty cycle square-wave PDC requires less energy than sinusoidal AC to inducing the same level of adult zebra mussel mortality.

Structure and stress state of Hawaiian island basalts penetrated by the Hawaii Scientific Drilling Project deep core hole

USGS Publications Warehouse

Morin, R.H.; Wilkens, R.H.

2005-01-01

As part of the Hawaii Scientific Drilling Project (HSDP), an exploratory hole was drilled in 1993 to a depth of 1056 meters below sea level (mbsl) and a deeper hole was drilled to 3098 mbsl in 1999. A set of geophysical well logs was obtained in the deeper hole that provides fundamental information regarding the structure and the state of stress that exist within a volcanic shield. The acoustic televiewer generates digital, magnetically oriented images of the borehole wall, and inspection of this log yields a continuous record of fracture orientation with depth and also with age to 540 ka. The data depict a clockwise rotation in fracture strike through the surficial Mauna Loa basalts that settles to a constant heading in the underlying Mauna Kea rocks. This behavior reflects the depositional slope directions of lavas and the locations of volcanic sources relative to the drill site. The deviation log delineates the trajectory of the well bore in three-dimensional space. This path closely follows changes in fracture orientation with depth as the drill bit is generally prodded perpendicular to fracture strike during the drilling process. Stress-induced breakouts observed in the televiewer log identify the orientations ot the maximum and minimum horizontal principal stresses to be north-south and east-west, respectively. This stress state is attributed to the combination of a sharp break in onshore-offshore slope that reduces stress east-west and the emergence of Kilauea that increases stress north-south. Breakouts are extensive and appear over approximately 30% of the open hole. Copyright 2005 by the American Geophysical Union.

The dynamics of photoinduced defect creation in amorphous chalcogenides: The origin of the stretched exponential function

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

Freitas, R. J.; Shimakawa, K.; Department of Electrical and Electronic Engineering, Gifu University, Gifu 501-1193

The article discusses the dynamics of photoinduced defect creations (PDC) in amorphous chalcogenides, which is described by the stretched exponential function (SEF), while the well known photodarkening (PD) and photoinduced volume expansion (PVE) are governed only by the exponential function. It is shown that the exponential distribution of the thermal activation barrier produces the SEF in PDC, suggesting that thermal energy, as well as photon energy, is incorporated in PDC mechanisms. The differences in dynamics among three major photoinduced effects (PD, PVE, and PDC) in amorphous chalcogenides are now well understood.

31P NMR and AFM studies on the destabilization of cell and model membranes by the major bovine seminal plasma protein, PDC-109.

PubMed

Damai, Rajani S; Sankhala, Rajeshwer S; Anbazhagan, Veerappan; Swamy, Musti J

2010-11-01

The effect of PDC-109 binding to dimyristoylphosphatidylcholine (DMPC) and dipalmitoylphosphatidylglycerol (DPPG) multilamellar vesicles (MLVs) and supported membranes was investigated by (31)P NMR spectroscopy and atomic force microscopy. Additionally, the effect of cholesterol on the binding of PDC-109 to phosphatidylcholine (PC) membranes was studied. Binding of PDC-109 to MLVs of DMPC and DPPG induced the formation of an isotropic signal in their (31)P NMR spectra, which increased with increasing protein/lipid ratio and temperature, consistent with protein-induced disruption of the MLVs and the formation of small unilamellar vesicles or micelles but not inverse hexagonal or cubic phases. Incorporation of cholesterol in the DMPC MLVs afforded a partial stabilization of the lamellar structure, consistent with previous reports of membrane stabilization by cholesterol. AFM results are consistent with the above findings and show that addition of PDC-109 leads to a complete breakdown of PC membranes. The fraction of isotropic signal in (31)P NMR spectra of DPPG in the presence of PDC-109 was less than that of DMPC under similar conditions, suggesting a significantly higher affinity of the protein for PC. Confocal microscopic studies showed that addition of PDC-109 to human erythrocytes results in a disruption of the plasma membrane and release of hemoglobin into the solution, which was dependent on the protein concentration and incubation time.

Structural Characterization of Phosducin and Its Complex with the 14-3-3 Protein*

PubMed Central

Kacirova, Miroslava; Kosek, Dalibor; Kadek, Alan; Man, Petr; Vecer, Jaroslav; Herman, Petr; Obsilova, Veronika; Obsil, Tomas

2015-01-01

Phosducin (Pdc), a highly conserved phosphoprotein involved in the regulation of retinal phototransduction cascade, transcriptional control, and modulation of blood pressure, is controlled in a phosphorylation-dependent manner, including the binding to the 14-3-3 protein. However, the molecular mechanism of this regulation is largely unknown. Here, the solution structure of Pdc and its interaction with the 14-3-3 protein were investigated using small angle x-ray scattering, time-resolved fluorescence spectroscopy, and hydrogen-deuterium exchange coupled to mass spectrometry. The 14-3-3 protein dimer interacts with Pdc using surfaces both inside and outside its central channel. The N-terminal domain of Pdc, where both phosphorylation sites and the 14-3-3-binding motifs are located, is an intrinsically disordered protein that reduces its flexibility in several regions without undergoing dramatic disorder-to-order transition upon binding to 14-3-3. Our data also indicate that the C-terminal domain of Pdc interacts with the outside surface of the 14-3-3 dimer through the region involved in Gtβγ binding. In conclusion, we show that the 14-3-3 protein interacts with and sterically occludes both the N- and C-terminal Gtβγ binding interfaces of phosphorylated Pdc, thus providing a mechanistic explanation for the 14-3-3-dependent inhibition of Pdc function. PMID:25971962

Poor allostimulatory function of liver plasmacytoid DC is associated with pro-apoptotic activity, dependent on regulatory T cells

PubMed Central

Tokita, Daisuke; Sumpter, Tina L.; Raimondi, Giorgio; Zahorchak, Alan F.; Wang, Zhiliang; Nakao, Atsunori; Mazariegos, George V.; Abe, Masanori; Thomson, Angus W.

2008-01-01

Background/Aims The liver is comparatively rich in plasmacytoid (p) dendritic cells (DC),- innate immune effector cells that are also thought to play key roles in the induction and regulation of adaptive immunity. Methods Liver and spleen pDC were purified from fms-like tyrosine kinase ligand-reated control or lipopolysaccharide-injected C57BL/10 mice. Flow cytometric and molecular biologic assays were used to characterize their function and interaction with naturally-occurring regulatory T cells (Treg). Results While IL-10 production was greater for freshly-isolated liver compared with splenic pDC, the former produced less bioactive IL-12p70. Moreover, liver pDC expressed a low Delta4/Jagged1 Notch ligand ratio, skewed towards T helper 2 cell differentiation/cytokine production, and promoted allogeneic CD4+ T cell apoptosis. T cell proliferation in response to liver pDC was, however, enhanced by blocking IL-10 function at the initiation of cultures. In the absence of naturally occurring CD4+CD25+ regulatory T cells, similar levels of T cell proliferation were induced by liver and spleen pDC and the pro-apoptotic activity of liver pDC was reversed. Conclusion The inferior T cell allostimulatory activity of in vivo-stimulated liver pDC may depend on the presence and function of Treg, a property that may contribute to inherent liver tolerogenicity. PMID:18926588

Dendritic cell fate is determined by BCL11A

PubMed Central

Ippolito, Gregory C.; Dekker, Joseph D.; Wang, Yui-Hsi; Lee, Bum-Kyu; Shaffer, Arthur L.; Lin, Jian; Wall, Jason K.; Lee, Baeck-Seung; Staudt, Louis M.; Liu, Yong-Jun; Iyer, Vishwanath R.; Tucker, Haley O.

2014-01-01

The plasmacytoid dendritic cell (pDC) is vital to the coordinated action of innate and adaptive immunity. pDC development has not been unequivocally traced, nor has its transcriptional regulatory network been fully clarified. Here we confirm an essential requirement for the BCL11A transcription factor in fetal pDC development, and demonstrate this lineage-specific requirement in the adult organism. Furthermore, we identify BCL11A gene targets and provide a molecular mechanism for its action in pDC commitment. Embryonic germ-line deletion of Bcl11a revealed an absolute cellular, molecular, and functional absence of pDCs in fetal mice. In adults, deletion of Bcl11a in hematopoietic stem cells resulted in perturbed yet continued generation of progenitors, loss of downstream pDC and B-cell lineages, and persisting myeloid, conventional dendritic, and T-cell lineages. Challenge with virus resulted in a marked reduction of antiviral response in conditionally deleted adults. Genome-wide analyses of BCL11A DNA binding and expression revealed that BCL11A regulates transcription of E2-2 and other pDC differentiation modulators, including ID2 and MTG16. Our results identify BCL11A as an essential, lineage-specific factor that regulates pDC development, supporting a model wherein differentiation into pDCs represents a primed “default” pathway for common dendritic cell progenitors. PMID:24591644

Development and Testing of The Lunar Resource Prospector Drill

NASA Astrophysics Data System (ADS)

Zacny, K.; Paulsen, G.; Kleinhenz, J.; Smith, J. T.; Quinn, J.

2017-12-01

The goal of the Lunar Resource Prospector (RP) mission is to capture and identify volatiles species within the top one meter layer of the lunar surface. The RP drill has been designed to 1. Generate cuttings and place them on the surface for analysis by the Near InfraRed Volatiles Spectrometer Subsystem (NIRVSS), and 2. Capture cuttings and transfer them to the Oxygen and Volatile Extraction Node (OVEN) coupled with the Lunar Advanced Volatiles Analysis (LAVA) subsystem. The RP drill is based on the TRL4 Mars Icebreaker drill and TRL5 LITA drill developed for capturing samples of ice and ice cemented ground on Mars, and represents over a decade of technology development effort. The TRL6 RP drill weighs approximately 15 kg and is rated at just over 500 Watt. The drill consists of: 1. Rotary-Percussive Drill Head, 2. Sampling Auger, 3. Brushing Station, 4. Feed Stage, and 5. Deployment Stage. To reduce sample handling complexity, the drill auger is designed to capture cuttings as opposed to cores. High sampling efficiency is possible through a dual design of the auger. The lower section has deep and low pitch flutes for retaining of cuttings. The upper section has been designed to efficiently move the cuttings out of the hole. The drill uses a "bite" sampling approach where samples are captured in 10 cm depth intervals. The first generation, TRL4 Icebreaker drill was tested in Mars chamber as well as in Antarctica and the Arctic. It demonstrated drilling at 1-1-100-100 level (1 meter in 1 hour with 100 Watt and 100 N Weight on Bit) in ice, ice cemented ground, soil, and rocks. The second generation, TRL5 LITA drill was deployed on a Carnegie Mellon University rover, called Zoe, and tested in Atacama, Antarctica, the Arctic, and Greenland. The tests demonstrated fully autonomous sample acquisition and delivery to a carousel. The modified LITA drill was tested in NASA GRC's lunar vacuum chamber at <10^-5 torr and <200 K. It demonstrated successful capture and transfer of volatile rich frozen samples to a crucible for analysis. The modified LITA drill has also been successfully vibration tested at NASA KSC. The drill was integrated with RP rover at NASA JSC and successfully tested in a lab and in the field, as well as on a large vibration table and steep slope. The latest TRL6 RP drill is currently undergoing testing at NASA GRC lunar chamber facilities.

Infrared Thermal Imaging During Ultrasonic Aspiration of Bone

NASA Astrophysics Data System (ADS)

Cotter, D. J.; Woodworth, G.; Gupta, S. V.; Manandhar, P.; Schwartz, T. H.

Ultrasonic surgical aspirator tips target removal of bone in approaches to tumors or aneurysms. Low profile angled tips provide increased visualization and safety in many high risk surgical situations that commonly were approached using a high speed rotary drill. Utilization of the ultrasonic aspirator for bone removal raised questions about relative amount of local and transmitted heat energy. In the sphenoid wing of a cadaver section, ultrasonic bone aspiration yielded lower thermal rise in precision bone removal than rotary mechanical drills, with maximum temperature of 31 °C versus 69 °C for fluted and 79 °C for diamond drill bits. Mean ultrasonic fragmentation power was about 8 Watts. Statistical studies using tenacious porcine cranium yielded mean power levels of about 4.5 Watts to 11 Watts and mean temperature of less than 41.1 °C. Excessively loading the tip yielded momentary higher power; however, mean thermal rise was less than 8 °C with bone removal starting at near body temperature of about 37 °C. Precision bone removal and thermal management were possible with conditions tested for ultrasonic bone aspiration.

Risk of developing palatally displaced canines in patients with early detectable dental anomalies: a retrospective cohort study

PubMed Central

GARIB, Daniela Gamba; LANCIA, Melissa; KATO, Renata Mayumi; OLIVEIRA, Thais Marchini; NEVES, Lucimara Teixeira das

2016-01-01

ABSTRACT The early recognition of risk factors for the occurrence of palatally displaced canines (PDC) can increase the possibility of impaction prevention. Objective To estimate the risk of PDC occurrence in children with dental anomalies identified early during mixed dentition. Material and Methods The sample comprised 730 longitudinal orthodontic records from children (448 females and 282 males) with an initial mean age of 8.3 years (SD=1.36). The dental anomaly group (DA) included 263 records of patients with at least one dental anomaly identified in the initial or middle mixed dentition. The non-dental anomaly group (NDA) was composed of 467 records of patients with no dental anomalies. The occurrence of PDC in both groups was diagnosed using panoramic and periapical radiographs taken in the late mixed dentition or early permanent dentition. The prevalence of PDC in patients with and without early diagnosed dental anomalies was compared using the chi-square test (p<0.01), relative risk assessments (RR), and positive and negative predictive values (PPV and NPV). Results PDC frequency was 16.35% and 6.2% in DA and NDA groups, respectively. A statistically significant difference was observed between groups (p<0.01), with greater risk of PDC development in the DA group (RR=2.63). The PPV and NPV was 16% and 93%, respectively. Small maxillary lateral incisors, deciduous molar infraocclusion, and mandibular second premolar distoangulation were associated with PDC. Conclusion Children with dental anomalies diagnosed during early mixed dentition have an approximately two and a half fold increased risk of developing PDC during late mixed dentition compared with children without dental anomalies. PMID:28076458

Technical advance: Generation of human pDC equivalents from primary monocytes using Flt3-L and their functional validation under hypoxia.

PubMed

Sekar, Divya; Brüne, Bernhard; Weigert, Andreas

2010-08-01

The division of labor between DC subsets is evolutionarily well-defined. mDC are efficient in antigen presentation, whereas pDC act as rheostats of the immune system. They activate NK cells, cause bystander activation of mDC, and interact with T cells to induce tolerance. This ambiguity positions pDC at the center of inflammatory diseases, such as cancer, arthritis, and autoimmune diseases. The ability to generate human mDC ex vivo made it possible to engineer them to suit therapy needs. Unfortunately, a similar, easily accessible system to generate human pDC is not available. We describe a method to generate human pDC equivalents ex vivo, termed mo-pDC from peripheral blood monocytes using Flt3-L. mo-pDC showed a characteristic pDC profile, such as high CD123 and BDCA4, but low CD86 and TLR4 surface expression and a low capacity to induce autologous lymphocyte proliferation and to phagocytose apoptotic debris in comparison with mDC. Interestingly, mo-pDC up-regulated the pDC lineage-determining transcription factor E2-2 as well as expression of BDCA2, which is under the transcriptional control of E2-2 but not its inhibitor ID2, during differentiation. mo-pDC produced high levels of IFN-alpha when pretreated overnight with TNF-alpha. Under hypoxia, E2-2 was down-regulated, and ID2 was induced in mo-pDC, whereas surface expression of MHCI, CD86, and BDCA2 was decreased. Furthermore, mo-pDC produced high levels of inflammatory cytokines when differentiated under hypoxia compared with normoxia. Hence, mo-pDC can be used to study differentiation and functions of human pDC under microenvironmental stimuli.

Two enzymatic reaction pathways in the formation of pyropheophorbide a.

PubMed

Suzuki, Yasuyo; Doi, Michio; Shioi, Yuzo

2002-01-01

The demethoxycarbonyl reaction of pheophorbide a in plants and algae was investigated. Two types of enzyme that catalyze alternative reactions in the formation of pyropheophorbide a were found. One enzyme, designated 'pheophorbidase (Phedase)', was purified nearly to homogeneity from cotyledons of radish (Raphanus sativus). This enzyme catalyzes the conversion of pheophorbide a to a precursor of pyropheophorbide a, C-13(2)-carboxylpyropheophorbide a, by demethylation, and then the precursor is decarboxylated non-enzymatically to yield pyropheophorbide a. The activity of Phedase was inhibited by the reaction product, methanol. The other enzyme, termed 'pheophorbide demethoxycarbonylase (PDC)', was highly purified from the Chl b-less mutant NL-105 of Chlamydomonas reinhardtii. This enzyme had produced no intermediate as shown in the Phedase reaction, indicating that it converts pheophorbide a directly into pyropheophorbide a, probably by nucleophilic reaction. Phedase and PDC consisted of both senescence-induced and constitutive enzymes. The molecular weight of both Phedases was 113 000 and of senescence-induced PDC was 170 000. The K (m) values against pheophorbide a for both Phedases were 14-15 muM and 283 muM for senescence-induced PDC. The activity of both Phedases was inhibited by the reaction product, methanol, whereas methanol had no specific effect on senescence-induced PDC. Phenylmethylsulfonic fluoride and N-ethylmaleimide inhibited the senescence-induced Phedase and PDC, respectively. Among the 23 species from 15 different families tested, Phedase activity was found in 10 species from three families. PDC activity was not detected in plants lacking Phedase activity, except for Chlamydomonas. Based on these findings, a likely conclusion is that at least two alternative pathways that are catalyzed by two different enzymes, Phedase and PDC, exist for the formation of pyropheophorbide a.

Comparison of the dental anomalies found in maxillary canine-first premolar transposition cases with those in palatally displaced canine cases.

PubMed

Scerri, Erica Sultana; McDonald, Fraser; Camilleri, Simon

2016-02-01

To compare the developmental dental anomalies associated with maxillary canine-first premolar (MxCP1) transposition and those of palatally displaced canine (PDC) with each other and with the background prevalence in the Maltese population in order to elucidate whether the two conditions have similar or differing genetic backgrounds. Dental records of 477 subjects with PDC, 57 subjects with MxCP1, and a control group of 500 subjects with no history of a PDC or tooth transposition were compared for canine eruption anomalies and hypodontia. A high frequency of bilateral occurrence was present for both canine malpositions and when unilateral, a trend to right-sided occurrence was evident. The occurrence of transpositions in the PDC group and of PDC in the MxCP1 group was higher than expected. The prevalence of incisor hypodontia was significantly higher in subjects with PDC and MxCP1, as compared to the control group. The size of the MxCP1 group is relatively small. The study population is a small isolated Caucasian population and the results may not be applicable to other populations. There is no significant difference between the MxCP1 and PDC groups in the prevalence or distribution of hypodontia and each of these groups exhibits a higher prevalence of the other canine anomaly. These findings support the theory that PDC and MxCP1 form part of a group of interrelated dental anomalies that share a common genetic basis. © The Author 2015. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Genetic engineering of Clostridium thermocellum DSM1313 for enhanced ethanol production.

PubMed

Kannuchamy, Saranyah; Mukund, Nisha; Saleena, Lilly M

2016-05-11

The twin problem of shortage in fossil fuel and increase in environmental pollution can be partly addressed by blending of ethanol with transport fuel. Increasing the ethanol production for this purpose without affecting the food security of the countries would require the use of cellulosic plant materials as substrate. Clostridium thermocellum is an anaerobic thermophilic bacterium with cellulolytic property and the ability to produce ethanol. But its application as biocatalyst for ethanol production is limited because pyruvate ferredoxin oxidoreductase, which diverts pyruvate to ethanol production pathway, has low affinity to the substrate. Therefore, the present study was undertaken to genetically modify C. thermocellum for enhancing its ethanol production capacity by transferring pyruvate carboxylase (pdc) and alcohol dehydrogenase (adh) genes of the homoethanol pathway from Zymomonas mobilis. The pdc and adh genes from Z. mobilis were cloned in pNW33N, and transformed to Clostridium thermocellum DSM 1313 by electroporation to generate recombinant CTH-pdc, CTH-adh and CTH-pdc-adh strains that carried heterologous pdc, adh, and both genes, respectively. The plasmids were stably maintained in the recombinant strains. Though both pdc and adh were functional in C. thermocellum, the presence of adh severely limited the growth of the recombinant strains, irrespective of the presence or absence of the pdc gene. The recombinant CTH-pdc strain showed two-fold increase in pyruvate carboxylase activity and ethanol production when compared with the wild type strain. Pyruvate decarboxylase gene of the homoethanol pathway from Z mobilis was functional in recombinant C. thermocellum strain and enhanced its ability to produced ethanol. Strain improvement and bioprocess optimizations may further increase the ethanol production from this recombinant strain.

Effect of polysaccharide of dendrobium candidum on proliferation and apoptosis of human corneal epithelial cells in high glucose

PubMed Central

Li, Qiangxiang; Chen, Jing; Li, Yajia; Chen, Ting; Zou, Jing; Wang, Hua

2017-01-01

Abstract Background: The aim of the study was to observe the effect of polysaccharide of dendrobium candidum (PDC) and high glucose on proliferation, apoptosis of human corneal epithelial cells (HCEC). Methods: The MTT method was used to screen and take the optimal high-glucose concentration, treatment time, and PDC concentration using HCEC and divide it into 4 groups: control group (C), high glucose group (HG), PDC group, and HG + PDC group. We observed and compared the effect of the 4 groups on HCEC proliferation by MTT, apoptosis by Annexin V-FITC/PI double fluorescent staining and flow cytometry (FCM), and expression of bax mRNA and bcl-2 mRNA by RT-qPCR. Results: Compared with the control group, proliferative activity of HCEC cells was reduced; the cells apoptosis ratio was increased; the expression of bax mRNA was increased, and the expression of bcl-2 mRNA was reduced in the HG group. Proliferative activity of HCEC cells in the PDC group was increased, and the expression of bcl-2 mRNA was increased but that of bax mRNA was decreased. Proliferative activity of HCEC cells in the HG + PDC group was increased, but it could not restore to the normal level; the expression of bax mRNA was significantly decreased but the expression of bcl-2 mRNA was significantly increased. Conclusions: Our results demonstrate that high glucose can inhibit proliferative activity and induce apoptosis of HCEC. PDC can improve the proliferative activity of HCEC cells under the high glucose environment and reduce the apoptosis of cells by regulating the expression of bax and bcl-2. PDC play a very important role on protecting and repairing of corneal epithelial cells damage in high glucose. PMID:28796073

Building an open-source robotic stereotaxic instrument.

PubMed

Coffey, Kevin R; Barker, David J; Ma, Sisi; West, Mark O

2013-10-29

This protocol includes the designs and software necessary to upgrade an existing stereotaxic instrument to a robotic (CNC) stereotaxic instrument for around $1,000 (excluding a drill), using industry standard stepper motors and CNC controlling software. Each axis has variable speed control and may be operated simultaneously or independently. The robot's flexibility and open coding system (g-code) make it capable of performing custom tasks that are not supported by commercial systems. Its applications include, but are not limited to, drilling holes, sharp edge craniotomies, skull thinning, and lowering electrodes or cannula. In order to expedite the writing of g-coding for simple surgeries, we have developed custom scripts that allow individuals to design a surgery with no knowledge of programming. However, for users to get the most out of the motorized stereotax, it would be beneficial to be knowledgeable in mathematical programming and G-Coding (simple programming for CNC machining). The recommended drill speed is greater than 40,000 rpm. The stepper motor resolution is 1.8°/Step, geared to 0.346°/Step. A standard stereotax has a resolution of 2.88 μm/step. The maximum recommended cutting speed is 500 μm/sec. The maximum recommended jogging speed is 3,500 μm/sec. The maximum recommended drill bit size is HP 2.

Utilization of fluorescent microspheres and a green fluorescent protein-marked strain for assessment of microbiological contamination of permafrost and ground ice core samples from the Canadian High Arctic.

PubMed

Juck, D F; Whissell, G; Steven, B; Pollard, W; McKay, C P; Greer, C W; Whyte, L G

2005-02-01

Fluorescent microspheres were applied in a novel fashion during subsurface drilling of permafrost and ground ice in the Canadian High Arctic to monitor the exogenous microbiological contamination of core samples obtained during the drilling process. Prior to each drill run, a concentrated fluorescent microsphere (0.5-microm diameter) solution was applied to the interior surfaces of the drill bit, core catcher, and core tube and allowed to dry. Macroscopic examination in the field demonstrated reliable transfer of the microspheres to core samples, while detailed microscopic examination revealed penetration levels of less than 1 cm from the core exterior. To monitor for microbial contamination during downstream processing of the permafrost and ground ice cores, a Pseudomonas strain expressing the green fluorescent protein (GFP) was painted on the core exterior prior to processing. Contamination of the processed core interiors with the GFP-expressing strain was not detected by culturing the samples or by PCR to detect the gfp marker gene. These methodologies were quick, were easy to apply, and should help to monitor the exogenous microbiological contamination of pristine permafrost and ground ice samples for downstream culture-dependent and culture-independent microbial analyses.

Utilization of Fluorescent Microspheres and a Green Fluorescent Protein-Marked Strain for Assessment of Microbiological Contamination of Permafrost and Ground Ice Core Samples from the Canadian High Arctic

PubMed Central

Juck, D. F.; Whissell, G.; Steven, B.; Pollard, W.; McKay, C. P.; Greer, C. W.; Whyte, L. G.

2005-01-01

Fluorescent microspheres were applied in a novel fashion during subsurface drilling of permafrost and ground ice in the Canadian High Arctic to monitor the exogenous microbiological contamination of core samples obtained during the drilling process. Prior to each drill run, a concentrated fluorescent microsphere (0.5-μm diameter) solution was applied to the interior surfaces of the drill bit, core catcher, and core tube and allowed to dry. Macroscopic examination in the field demonstrated reliable transfer of the microspheres to core samples, while detailed microscopic examination revealed penetration levels of less than 1 cm from the core exterior. To monitor for microbial contamination during downstream processing of the permafrost and ground ice cores, a Pseudomonas strain expressing the green fluorescent protein (GFP) was painted on the core exterior prior to processing. Contamination of the processed core interiors with the GFP-expressing strain was not detected by culturing the samples or by PCR to detect the gfp marker gene. These methodologies were quick, were easy to apply, and should help to monitor the exogenous microbiological contamination of pristine permafrost and ground ice samples for downstream culture-dependent and culture-independent microbial analyses. PMID:15691963

A Brain-Machine-Brain Interface for Rewiring of Cortical Circuitry after Traumatic Brain Injury

DTIC Science & Technology

2011-09-01

parietal bones, and a threaded rod was implanted into the interparietal bone. These were affixed to the skull with dental acrylic. A hybrid, 16...then sealed with a silicone polymer (Kwik-Cast, WPI). The base of the probe connector was lowered onto the dental acrylic and fixed into place. An...the skull using a dental drill with a trephine bit over the cortex contralateral to the dominant forelimb. A total of 14 animals received CCI in the

A Process Evaluation of Project Developmental Continuity, Interim Report VII, Volume 1: Findings from the PDC Implementation Study.

ERIC Educational Resources Information Center

Smith, Allen G.; And Others

This third year interim report, one of a series of documents on the evaluation of Project Developmental Continuity (PDC), presents findings from three major analyses of program implementation; measurement of the extent each program has implemented the basic PDC Guidelines; a description of patterns of that implementation; and analysis of some…

A Process Evaluation of Project Developmental Continuity: Final Report of the PDC Feasibility Study, 1974-1977.

ERIC Educational Resources Information Center

Love, John M.; And Others

This is the final report of the 3-year feasibility phase of a projected 7-year longitudinal evaluation of Project Developmental Continuity (PDC), a Head Start demonstration program aimed at providing educational and developmental continuity between children's Head Start and primary school experiences. Chapter I gives an overview of the PDC program…

Natural amines inhibit activation of human plasmacytoid dendritic cells through CXCR4 engagement

PubMed Central

Smith, Nikaïa; Pietrancosta, Nicolas; Davidson, Sophia; Dutrieux, Jacques; Chauveau, Lise; Cutolo, Pasquale; Dy, Michel; Scott-Algara, Daniel; Manoury, Bénédicte; Zirafi, Onofrio; McCort-Tranchepain, Isabelle; Durroux, Thierry; Bachelerie, Françoise; Schwartz, Olivier; Münch, Jan; Wack, Andreas; Nisole, Sébastien; Herbeuval, Jean-Philippe

2017-01-01

Plasmacytoid dendritic cells (pDC) are specialized in secretion of type I interferon in response to pathogens. Here we show that natural monoamines and synthetic amines inhibit pDC activation by RNA viruses. Furthermore, a synthetic analogue of histamine reduces type I interferon production in a mouse model of influenza infection. We identify CXC chemokine receptor 4 (CXCR4) as a receptor used by amines to inhibit pDC. Our study establishes a functional link between natural amines and the innate immune system and identifies CXCR4 as a potential ‘on-off' switch of pDC activity with therapeutic potential. PMID:28181493

Induction of tolerance to poison ivy urushiol in the guinea pig by epicutaneous application of the structural analog 5-methyl-3-n-pentadecylcatechol.

PubMed

Stampf, J L; Benezra, C; Byers, V; Castagnoli, N

1986-05-01

Previous studies have established that epicutaneous application of 5-methyl-3-n-pentadecylcatechol (5-Me-PDC), a synthetic analog of a poison ivy urushiol component, leads to immune tolerance to 3-n-pentadecylcatechol (PDC) in mice. The induction of tolerance by 5-Me-PDC may be mediated by a protein conjugate formed via selective reaction of thiol nucleophiles present on the carrier macromolecule with the corresponding o-quinone derived from the parent catechol. In order to examine further the tolerogenic properties of 5-Me-PDC, we have extended our studies to the guinea pig, the generally accepted experimental species for the study of contact allergy. The results have established that specific immune tolerance to poison ivy urushiol is induced following 2 epicutaneous applications of the PDC analog. Furthermore, we were able to show that the treated animals remained tolerant for at least 6 weeks, a period of time comparable to that observed following the intravenous administration of the O,O-bis-acetyl derivative of PDC. The data point to the possibility of developing a therapeutically effective topical tolerogen for poison ivy contact dermatitis.

Antimicrobial activity and mechanism of PDC213, an endogenous peptide from human milk.

PubMed

Sun, Yazhou; Zhou, Yahui; Liu, Xiao; Zhang, Fan; Yan, Linping; Chen, Ling; Wang, Xing; Ruan, Hongjie; Ji, Chenbo; Cui, Xianwei; Wang, Jiaqin

2017-02-26

Human milk has always been considered an ideal source of elemental nutrients to both preterm and full term infants in order to optimally develop the infant's tissues and organs. Recently, hundreds of endogenous milk peptides were identified in human milk. These peptides exhibited angiotensin-converting enzyme inhibition, immunomodulation, or antimicrobial activity. Here, we report the antimicrobial activity and mechanism of a novel type of human antimicrobial peptide (AMP), termed PDC213 (peptide derived from β-Casein 213-226 aa). PDC213 is an endogenous peptide and is present at higher levels in preterm milk than in full term milk. The inhibitory concentration curve and disk diffusion tests showed that PDC213 had obvious antimicrobial against S. aureus and Y. enterocolitica, the common nosocomial pathogens in neonatal intensive care units (NICUs). Fluorescent dye methods, electron microscopy experiments and DNA-binding activity assays further indicated that PDC213 can permeabilize bacterial membranes and cell walls rather than bind intracellular DNA to kill bacteria. Together, our results suggest that PDC213 is a novel type of AMP that warrants further investigation. Copyright © 2017 Elsevier Inc. All rights reserved.

Mitochondrial transcription factor A serves as a danger signal by augmenting plasmacytoid dendritic cell responses to DNA.

PubMed

Julian, Mark W; Shao, Guohong; Bao, Shengying; Knoell, Daren L; Papenfuss, Tracey L; VanGundy, Zachary C; Crouser, Elliott D

2012-07-01

Plasmacytoid dendritic cells (pDC) are potent APCs known to regulate immune responses to self-Ags, particularly DNA. The mitochondrial fraction of necrotic cells was found to most potently promote human pDC activation, as reflected by type I IFN release, which was dependent upon the presence of mitochondrial DNA and involved TLR9 and receptors for advanced glycation end products. Mitochondrial transcription factor A (TFAM), a highly abundant mitochondrial protein that is functionally and structurally homologous to high mobility group box protein 1, was observed to synergize with CpG-containing oligonucleotide, type A, DNA to promote human pDC activation. pDC type I IFN responses to TFAM and CpG-containing oligonucleotide, type A, DNA indicated their engagement with receptors for advanced glycation end products and TLR9, respectively, and were dependent upon endosomal processing and PI3K, ERK, and NF-κB signaling. Taken together, these results indicate that pDC contribute to sterile immune responses by recognizing the mitochondrial component of necrotic cells and further incriminate TFAM and mitochondrial DNA as likely mediators of pDC activation under these circumstances.

Plasmacytoid Dendritic Cells Require Direct Infection To Sustain the Pulmonary Influenza A Virus-Specific CD8 T Cell Response

PubMed Central

Hemann, Emily A.; Sjaastad, Louisa E.; Langlois, Ryan A.

2015-01-01

ABSTRACT Following influenza A virus (IAV) infection, development of a robust IAV-specific CD8 T cell response is required for clearance of primary infection and enhances memory protection. Following IAV infection, plasmacytoid dendritic cells (pDC) or CD8α+ DC regulate pulmonary effector CD8 T cell responses within the lung. Without this DC-T cell interaction, insufficient effector CD8 T cells are maintained in the lungs, leading to enhanced morbidity and mortality. Previous studies have demonstrated that pDC are capable of classical presentation or cross-presentation of IAV antigens and could potentially regulate IAV-specific CD8 T cell responses through either mechanism. Our results demonstrate that pDC from the lungs of donor mice infected with an IAV that is not able to replicate in hematopoietic cells (142t-IAV), unlike donor pDC isolated from the lungs of control infected mice, are not able to rescue the host IAV-specific CD8 T cell response from apoptosis. This indicates that pDC must utilize the direct presentation pathway for this rescue. This inability of pDC from 142t-IAV donors to rescue the IAV-specific CD8 T cell response is not due to differences in the overall ability of 142t-IAV to replicate within the lungs or generate defective viral genomes or to differences in levels of costimulatory molecules required for this interaction. We further demonstrate that bypassing the antigen presentation pathway by coating the 142t-IAV pDC with IAV peptide epitopes restores their ability to rescue the IAV-specific CD8 T cell response. IMPORTANCE IAV continues to be a global health burden, infecting 5 to 20% of the global population annually. Continued investigation into the mechanisms that mediate protective immune responses against IAV is important to improving current vaccination and antiviral strategies antagonistic toward IAV. Our findings presented herein demonstrate a key requirement for pDC promotion of effector CD8 T cell survival: that rather than utilizing cross-presentation, pDC must be infected and utilize the endogenous pathway for presentation of antigens to CD8 T cells during in vivo IAV infections. This suggests that targeting presentation via the endogenous pathway in pDC could be important for the development of unique antiviral cellular therapies. PMID:26719269

Single dose parenteral hyposensitization to poison ivy urushiol in guinea pigs.

PubMed

Walker, L A; Watson, E S; elSohly, M A

1995-08-01

Studies were carried out in guinea pigs to evaluate the potential for single dose hyposensitization to poison ivy urushiol dermatitis. Sensitization was induced by topical application of 1 mg of poison ivy urushiol to the back of the neck. In the first series of studies, three different analogs of poison ivy urushiol were studied: 1) a mixture of pentadecyl and heptadecyl catechols (PDC/HDC), the saturated side chain analog of the natural urushiol mixture; 2) a mixture of the diacetate esters of PDC and HDC (PDC/HDC Ac), the esterified form of the saturated sidechain analogs; 3) 2-n-pentadecyl hydroquinone diacetate (HQ Ac). Each of these compounds was administered as 5 mg of the free catechol i.m. each week for three weeks. A vehicle group received only corn oil injections. Reactivity to poison ivy urushiol (PIU) challenge was evaluated in skin tests at 1 and 5 weeks post-treatment. PDC/HDC Ac induced a marked reduction in both the incidence and the severity of lesions induced by PIU at both 1 and at 5 weeks post-treatment. Other analogs were ineffective at 5 weeks post-treatment, and were less effective than PDC/HDC Ac at 1 week post-treatment. In a second series of experiments, the efficacy of PDC/HDC Ac was evaluated in both single and multiple dose regiments. One treatment group received 5 mg of PDC/HDC Ac intramuscularly each week for 4 weeks, while another treatment group received a single dose of 20 mg PDC/HDC Ac i.m. Corresponding vehicle control groups were also included. At 1 week post-treatment in the single dose group, the PDC/HDC Ac was only modestly effective, with some reduction of severity of lesions at the higher challenge doses of PIU. However, at 4 and 7 weeks post-treatment, both the incidence and the severity of the lesions at all challenge doses were reduced. In the multiple dose group, the incidence and severity of lesions are reduced at 1 week and 4 weeks post-treatment (4 weeks and 7 weeks after the initial dose) but were not significantly different from the single dose group. These findings indicate that the diacetate ester of PDC/HDC is an effective hyposensitizer to poison ivy urushiol, and that this hyposensitization can be reasonably accomplished in a single dose treatment regimen.

New approaches to subglacial bedrock drilling technology

NASA Astrophysics Data System (ADS)

Talalay, Pavel; Sun, Youhong; Zhao, Yue; Xue, Jun; Chen, Chen; Markov, Alexey; Xu, Huiwen; Gong, Wenbin; Han, Wei; Zheng, Zhichuan; Cao, Pinlu; Wang, Rusheng; Zhang, Nan; Yu, Dahui; Fan, Xiaopeng; Hu, Zhengyi; Yang, Cheng; Han, Lili; Sysoev, Mikhail

2013-04-01

Drilling to bedrock of ice sheets and glaciers offers unique opportunities to research processes acting at the bed for paleo-climatic and paleo-environmental recording, basal sliding studies, subglacial geology and tectonics investigations, prospecting and exploration for minerals covered by ice. Retrieving bedrock samples under ice sheets and glaciers is a very difficult task. Drilling operations are complicated by extremely low temperature at the surface of, and within glaciers, and by glacier flow, the absence of roads and infrastructures, storms, winds, snowfalls, etc. In order to penetrate through the ice sheet or glacier up to the depth of at least 1000 m and to pierce the bedrock to the depth of several meters from ice - bedrock boundary the development activity already has been started in Polar Research Center at Jilin University, China. All drilling equipment (two 50-kW diesel generators, winch, control desk, fluid dumping station, etc.) is installed inside a movable sledge-mounted warm-keeping and wind-protecting drilling shelter that has dimensions of 8.8 ×2.8 × 3.0 m. Mast has two positions: horizontal for transportation and vertical working position (mast height is 12 m). Drilling shelter can be transported to the chosen site with crawler-tractor, aircraft or helicopter. In case of carriage by air the whole drilling shelter was designed to be disassembled into pieces "small" enough to ship by aircraft. Weight and sizes of each component has been minimized to lower the cost of transportation and to meet weight restrictions for transportation. Total weight of drilling equipment (without drilling fluid) is near 15 tons. Expected time of assembling and preparing for drilling is 2 weeks. If drilling shelter is transported with crawler-tractor (for example, in Antarctic traverses) all equipment is ready to start drilling immediately upon arrival to the site. To drill through ice and bedrock a new, modified version of the cable-suspended electromechanical ice core drill is designed and tested. The expected average daily production of ice drilling would be not less than 25 m/day. The lower part of the drill is adapted for coring bed-rock using special tooth diamond bit. Deep ice coring requires a drilling fluid in the borehole during operation in order to keep the hole open and to compensate the hydrostatic pressures acting to close it. At present there are no ideal low-temperature drilling fluids as all of them are environmental and health hazardous substances. The new approaches of subglacial bedrock drilling technology are connected with utilization of environmental friendly, low-toxic materials, e.g. low-molecular dimethyl siloxane oils or aliphatic synthetic ester of ESTISOL™ 140 type. They have suitable density-viscosity properties, and can be consider as a viable alternative for drilling in glaciers and subglacial bedrock.

The Great British Columbia ShakeOut - Seismology and kinaesthetic learning

NASA Astrophysics Data System (ADS)

Wynne, P.

2011-12-01

By the time this paper is presented British Columbia will have experienced two, province wide ShakeOut drills. In the first drill over 10% of the population (470,000 people) participated in the "Drop, Cover and Hold On" drill. Natural Resources Canada (NRCan) was one of several federal, provincial, municipal, non-governmental and private sector agencies who organized the drill under the auspices of the BC Earthquake Alliance. The BC drill followed the Great California ShakeOut model (which is coordinated by the Earthquake Country Alliance) and received tremendous support from the Southern California Earthquake Center. NRCan is responsible for the monitoring and research of earthquakes in Canada and is a science-based department. The ShakeOut drill afforded us an opportunity to take our authoritative science straight to the people and help them better understand the seismic hazard in the province. Universities, public schools, daycares, and entire offices participated in the drill and it became the subject of dinner-time conversations across the province. The drill prompted questions like: "How worried should we be about earthquakes?" "How prepared are we as a family or as a work place?" "What else do we need to do, to be prepared?". The kinaesthetic aspect of the drill, physically dropping to the ground, taking cover, and holding on makes it memorable - you end up in a bit of a silly position, so there are lots of giggles. Being memorable is important because in a real earthquake the natural instinct is to run - the very thing you must not do. The drill provides an opportunity for people to attain a body-memory, to practice appropriate behaviour so they know what to do, without thinking, in a real earthquake. The first drill was on January 26th, 2011 the date of the last Cascadia megathrust earthquake. That date conflicted with province wide high school exams, so almost no high schools participated in the drill - they represent an important target demographic because the students are the next generation of parents. The second drill is planned for October 20 at 10:20. Tying the drill date to an earthquake that was 311 years ago might also have been counter productive. People may have thought "If it hasn't happened in over 300 years, how worried should I be?". In October 2011 we are "growing the drill" by focussing our outreach efforts on people with mobility issues. In the future we plan to add messaging about securing your space and tsunamis. In 2012 Yukon Canada will be hosting their first ShakeOut drill.

Coring device with a improved core sleeve and anti-gripping collar with a collective core catcher

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

Story, A.L.; Filshtinsky, M.

1986-01-28

This patent describes an improved coring apparatus used in combination with a coring bit and drill string. This device consists of: an outer driving structure adapted to be connected at one end to the coring bit for cutting a core in a borehole, and at the other end to the lower end of the drill string in telescoping and co-rotatable manner therewith; an inner barrel disposed within the outer driving structure and including a lower end portion adjacent to the bit; first means supporting the inner barrel in spaced relationship to the outer driving structure while permitting rotation of themore » driving structure with respect to the inner barrel; a woven metal mesh sleeve mounted in surrounding relation on at least a portion of the exterior surface of the inner barrel; second means, connected to a free end of the sleeve opposite the leading portion of the sleeve, for maintaining the portion of the sleeve which surrounds the inner barrel in compression and to maintain an inside diameter greater than the outside diameter of the inner barrel of the portion of the sleeve surrounding the inner barrel while the portion of the sleeve positioned inside the inner barrel being in tension to grip and compress a core received within the sleeve and having an outside diameter less than the inside diameter of the inner barrel when in tension, wherein the second means is also for engaging the core when the means is drawn into the inner barrel, and third means positioned within the inner barrel and connected to the leading portion of the sleeve to draw the sleeve within the inner barrel and to apply tension to the portion of the sleeve within the barrel to encase and grip the core as it is cut.« less

Estrogen Receptor α Deficiency Modulates TLR Ligand-Mediated PDC-TREM Expression in Plasmacytoid Dendritic Cells in Lupus-Prone Mice.

PubMed

Scott, Jennifer L; Cunningham, Melissa A; Naga, Osama S; Wirth, Jena R; Eudaly, Jackie G; Gilkeson, Gary S

2015-12-15

Female lupus-prone NZM2410 estrogen receptor α (ERα)-deficient mice are protected from renal disease and have prolonged survival compared with wild-type littermates; however, the mechanism of protection is unknown. Plasmacytoid dendritic cells (pDCs) and type I IFN drive lupus pathogenesis. Estrogen acting via ERα enhances both pDC development and IFN production. The objectives for this study were to determine if ERα modulates pDC function and IFN activity in predisease NZM2410 mice as a possible protective mechanism of ERα deficiency in lupus-prone mice. We measured the effect of ERα deficiency on spleen pDC frequency, number, maturation, and activation state. ERα deficiency reduced type I IFN activity and the frequency of MHC class II(+) pDCs in the spleen without altering overall pDC frequency, number, or maturation state. Additionally, ERα-deficient NZM2410 mice had a significantly decreased frequency of pDCs expressing PDC-TREM, a modulator of TLR-mediated IFN production. After in vitro TLR9 stimulation, ERα deficiency significantly reduced the expression of PDC-TREM on pDCs from both NZM2410 and C57BL/6 mice. Thus, we have identified a significant effect of ERα deficiency on pDCs in predisease NZM2410 mice, which may represent a mechanism by which ERα deficiency protects NZM2410 mice from lupuslike disease. Copyright © 2015 by The American Association of Immunologists, Inc.

Estrogen receptor alpha deficiency modulates TLR ligand mediated PDC-TREM expression in plasmacytoid dendritic cells in lupus prone mice

PubMed Central

Scott, Jennifer L; Cunningham, Melissa A; Naga, Osama S; Wirth, Jena R; EuDaly, Jackie G; Gilkeson, Gary S

2016-01-01

Female lupus prone NZM2410 estrogen receptor alpha (ERα) deficient mice are protected from renal disease and have prolonged survival compared to wild type (WT) littermates, however the mechanism of protection is unknown. Plasmacytoid dendritic cells (pDCs) and type I interferon (IFN) drive lupus pathogenesis. Estrogen acting via ERα enhances both pDC development and IFN production. The objectives for this study were to determine if ERα modulates pDC function and IFN activity in pre-disease NZM2410 mice as a possible protective mechanism of ERα deficiency in lupus prone mice. We measured the effect of ERα deficiency on spleen pDC frequency, number, maturation, and activation state. ERα deficiency reduced type I IFN activity and the frequency of MHCII+ pDCs in the spleen without altering overall pDC frequency, number, or maturation state. Additionally, ERα deficient NZM2410 mice had a significantly decreased frequency of pDCs expressing PDC-TREM, a modulator of toll-like receptor (TLR) mediated IFN production. After in vitro TLR9 stimulation, ERα deficiency significantly reduced the expression of PDC-TREM on pDCs from both NZM2410 and C57BL/6 mice. Thus, we have identified a significant effect of ERα deficiency on pDCs in pre-disease NZM2410 mice, which may represent a mechanism by which ERα deficiency protects NZM2410 mice from lupus like disease. PMID:26553076

Epstein-Barr Virus Promotes Interferon-α Production by Plasmacytoid Dendritic Cells

PubMed Central

Quan, Timothy E.; Roman, Robert M.; Rudenga, Benjamin J.; Holers, V. Michael; Craft, Joe

2010-01-01

Objective Epstein-Barr virus (EBV) infection has been linked to systemic lupus erythematosus (SLE) as demonstrated by the presence of increased seroprevalence and elevated viral loads, but the mechanism of this linkage has not been elucidated. Increased IFN-α levels and signatures, associated with innate immune responses, have been found in patients with SLE. Plasmacytoid dendritic cells (pDC) are innate immune cells that mediate viral immunity by producing large quantities of interferon alpha (IFN-α), but the role they play during infection with EBV remains unclear. To address this issue, we investigated the ability of EBV to promote IFN-α production by pDC in healthy subjects. Methods Human pDC were sorted and cultured in the presence of EBV, EBV small RNA (EBER), and EBV double-stranded DNA (dsDNA). IFN-α production by pDC was measured by enzyme-linked immunosorbent assay (ELISA), with activation of these cells measured by flow cytometry. Results We demonstrate that EBV DNA and RNA promote IFN-α production by human pDC through engagement of Toll-like receptor (TLR) 9 and TLR7, respectively, with initial viral recognition by pDC mediated by binding to major histocompatibility (MHC) class II molecules. Conclusion These data demonstrate that MHC class II-specific engagement by virus and subsequent viral nucleic acid recognition mediates IFN-α production by pDC. Our results suggest that elevated levels of IFN-α found in lupus patients may be a result of aberrantly controlled chronic viral infection. PMID:20178121

Risk of developing palatally displaced canines in patients with early detectable dental anomalies: a retrospective cohort study.

PubMed

Garib, Daniela Gamba; Lancia, Melissa; Kato, Renata Mayumi; Oliveira, Thais Marchini; Neves, Lucimara Teixeira das

2016-01-01

To estimate the risk of PDC occurrence in children with dental anomalies identified early during mixed dentition. The sample comprised 730 longitudinal orthodontic records from children (448 females and 282 males) with an initial mean age of 8.3 years (SD=1.36). The dental anomaly group (DA) included 263 records of patients with at least one dental anomaly identified in the initial or middle mixed dentition. The non-dental anomaly group (NDA) was composed of 467 records of patients with no dental anomalies. The occurrence of PDC in both groups was diagnosed using panoramic and periapical radiographs taken in the late mixed dentition or early permanent dentition. The prevalence of PDC in patients with and without early diagnosed dental anomalies was compared using the chi-square test (p<0.01), relative risk assessments (RR), and positive and negative predictive values (PPV and NPV). PDC frequency was 16.35% and 6.2% in DA and NDA groups, respectively. A statistically significant difference was observed between groups (p<0.01), with greater risk of PDC development in the DA group (RR=2.63). The PPV and NPV was 16% and 93%, respectively. Small maxillary lateral incisors, deciduous molar infraocclusion, and mandibular second premolar distoangulation were associated with PDC. Children with dental anomalies diagnosed during early mixed dentition have an approximately two and a half fold increased risk of developing PDC during late mixed dentition compared with children without dental anomalies.

Intranasal Chromium Induces Acute Brain and Lung Injuries in Rats: Assessment of Different Potential Hazardous Effects of Environmental and Occupational Exposure to Chromium and Introduction of a Novel Pharmacological and Toxicological Animal Model.

PubMed

Salama, Abeer; Hegazy, Rehab; Hassan, Azza

2016-01-01

Chromium (Cr) is used in many industries and it is widely distributed in the environment. Exposure to Cr dust has been reported among workers at these industries. Beside its hazardous effects on the lungs, brain injury could be induced, as the absorption of substances through the nasal membrane has been found to provide them a direct delivery to the brain. We investigated the distribution and the effects of Cr in both brain and lung following the intranasal instillation of potassium dichromate (inPDC) in rats. Simultaneously, we used the common intraperitoneal (ipPDC) rat model of acute Cr-toxicity for comparison. Thirty male Wistar rats were randomly allocated into five groups (n = 6); each received a single dose of saline, ipPDC (15 mg/kg), or inPDC in three dose levels: 0.5, 1, or 2 mg/kg. Locomotor activity was assessed before and 24 h after PDC administration, then, the lungs and brain were collected for biochemical, histopathological, and immunohistochemical investigations. Treatment of rats with ipPDC resulted in a recognition of 36% and 31% of the injected dose of Cr in the brain and lung tissues, respectively. In inPDC-treated rats, targeting the brain by Cr was increased in a dose-dependent manner to reach 46% of the instilled dose in the group treated with the highest dose. Moreover, only this high dose of inPDC resulted in a delivery of a significant concentration of Cr, which represented 42% of the instilled dose, to the lungs. The uppermost alteration in the rats locomotor activity as well as in the brain and lung histopathological features and contents of oxidative stress biomarkers, interleukin-1β (IL-1β), phosphorylated protein kinase B (PKB), and cyclooxygenase 2 (COX-2) were observed in the rats treated with inPDC (2 mg/kg). The findings revealed that these toxic manifestations were directly proportional to the delivered concentration of Cr to the tissue. In conclusion, the study showed that a comparably higher concentrations of Cr and more elevated levels of oxidative stress and inflammatory markers were observed in brain and lung tissues of rats subjected to inPDC in a dose that is just 0.13 that of ipPDC dose commonly used in Cr-induced toxicity studies. Therefore, the study suggests a high risk of brain-targeting injury among individuals environmentally or occupationally exposed to Cr dust, even in low doses, and an additional risk of lung injury with higher Cr concentrations. Moreover, the study introduces inPDC (2 mg/kg)-instillation as a new experimental animal model suitable to study the acute brain and lung toxicities induced by intranasal exposure to Cr compounds.

Intranasal Chromium Induces Acute Brain and Lung Injuries in Rats: Assessment of Different Potential Hazardous Effects of Environmental and Occupational Exposure to Chromium and Introduction of a Novel Pharmacological and Toxicological Animal Model

PubMed Central

Salama, Abeer; Hassan, Azza

2016-01-01

Chromium (Cr) is used in many industries and it is widely distributed in the environment. Exposure to Cr dust has been reported among workers at these industries. Beside its hazardous effects on the lungs, brain injury could be induced, as the absorption of substances through the nasal membrane has been found to provide them a direct delivery to the brain. We investigated the distribution and the effects of Cr in both brain and lung following the intranasal instillation of potassium dichromate (inPDC) in rats. Simultaneously, we used the common intraperitoneal (ipPDC) rat model of acute Cr-toxicity for comparison. Thirty male Wistar rats were randomly allocated into five groups (n = 6); each received a single dose of saline, ipPDC (15 mg/kg), or inPDC in three dose levels: 0.5, 1, or 2 mg/kg. Locomotor activity was assessed before and 24 h after PDC administration, then, the lungs and brain were collected for biochemical, histopathological, and immunohistochemical investigations. Treatment of rats with ipPDC resulted in a recognition of 36% and 31% of the injected dose of Cr in the brain and lung tissues, respectively. In inPDC-treated rats, targeting the brain by Cr was increased in a dose-dependent manner to reach 46% of the instilled dose in the group treated with the highest dose. Moreover, only this high dose of inPDC resulted in a delivery of a significant concentration of Cr, which represented 42% of the instilled dose, to the lungs. The uppermost alteration in the rats locomotor activity as well as in the brain and lung histopathological features and contents of oxidative stress biomarkers, interleukin-1β (IL-1β), phosphorylated protein kinase B (PKB), and cyclooxygenase 2 (COX-2) were observed in the rats treated with inPDC (2 mg/kg). The findings revealed that these toxic manifestations were directly proportional to the delivered concentration of Cr to the tissue. In conclusion, the study showed that a comparably higher concentrations of Cr and more elevated levels of oxidative stress and inflammatory markers were observed in brain and lung tissues of rats subjected to inPDC in a dose that is just 0.13 that of ipPDC dose commonly used in Cr-induced toxicity studies. Therefore, the study suggests a high risk of brain-targeting injury among individuals environmentally or occupationally exposed to Cr dust, even in low doses, and an additional risk of lung injury with higher Cr concentrations. Moreover, the study introduces inPDC (2 mg/kg)-instillation as a new experimental animal model suitable to study the acute brain and lung toxicities induced by intranasal exposure to Cr compounds. PMID:27997619

Accuracy improvements of gyro-based measurement-while-drilling surveying instruments by a laser testing method

NASA Astrophysics Data System (ADS)

Li, Rong; Zhao, Jianhui; Li, Fan

2009-07-01

Gyroscope used as surveying sensor in the oil industry has been proposed as a good technique for measurement-whiledrilling (MWD) to provide real-time monitoring of the position and the orientation of the bottom hole assembly (BHA).However, drifts in the measurements provided by gyroscope might be prohibitive for the long-term utilization of the sensor. Some usual methods such as zero velocity update procedure (ZUPT) introduced to limit these drifts seem to be time-consuming and with limited effect. This study explored an in-drilling dynamic -alignment (IDA) method for MWD which utilizes gyroscope. During a directional drilling process, there are some minutes in the rotary drilling mode when the drill bit combined with drill pipe are rotated about the spin axis in a certain speed. This speed can be measured and used to determine and limit some drifts of the gyroscope which pay great effort to the deterioration in the long-term performance. A novel laser assembly is designed on the wellhead to count the rotating cycles of the drill pipe. With this provided angular velocity of the drill pipe, drifts of gyroscope measurements are translated into another form that can be easy tested and compensated. That allows better and faster alignment and limited drifts during the navigation process both of which can reduce long-term navigation errors, thus improving the overall accuracy in INS-based MWD system. This article concretely explores the novel device on the wellhead designed to test the rotation of the drill pipe. It is based on laser testing which is simple and not expensive by adding a laser emitter to the existing drilling equipment. Theoretical simulations and analytical approximations exploring the IDA idea have shown improvement in the accuracy of overall navigation and reduction in the time required to achieve convergence. Gyroscope accuracy along the axis is mainly improved. It is suggested to use the IDA idea in the rotary mode for alignment. Several other practical aspects of implementing this approach are evaluated and compared.

A Process Evaluation of Project Developmental Continuity, Interim Report VII, Volume 3: Assessment of Program Impact Through the Head Start Year.

ERIC Educational Resources Information Center

Granville, Arthur C.; And Others

This interim report, part of a series of documents examining the feasibility of the longitudinal evaluation of Project Developmental Continuity (PDC), presents the results of an analysis of PDC impact at the Head Start level, using Spring 1977 data. PDC is a Head Start Demonstration Program aimed at providing educational and developmental…

The Pseudorabies Virus Glycoprotein gE/gI Complex Suppresses Type I Interferon Production by Plasmacytoid Dendritic Cells

PubMed Central

Lamote, Jochen A. S.; Kestens, Manon; Van Waesberghe, Cliff; Delva, Jonas; De Pelsmaeker, Steffi; Devriendt, Bert

2017-01-01

ABSTRACT Plasmacytoid dendritic cells (pDC) play a central role in the antiviral immune response, both in the innate response and in shaping the adaptive response, mainly because of their ability to produce massive amounts of type I interferon (TI-IFN). Here, we report that cells infected with the live attenuated Bartha vaccine strain of porcine alphaherpesvirus pseudorabies virus (PRV) trigger a dramatically increased TI-IFN response by porcine primary pDC compared to cells infected with wild-type PRV strains (Becker and Kaplan). Since Bartha is one of the relatively few examples of a highly successful alphaherpesvirus vaccine, identification of factors that may contribute to its efficacy may provide insights for the rational design of other alphaherpesvirus vaccines. The Bartha vaccine genome displays several mutations compared to the genome of wild-type PRV strains, including a large deletion in the unique short (US) region, encompassing the glycoprotein E (gE), gI, US9, and US2 genes. Using recombinant PRV Becker strains harboring the entire Bartha US deletion or single mutations in the four affected US genes, we demonstrate that the absence of the viral gE/gI complex contributes to the observed increased IFN-α response. Furthermore, we show that the absence of gE leads to an enhanced extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation in pDC, which correlates with a higher TI-IFN production by pDC. In conclusion, the PRV Bartha vaccine strain triggers strongly increased TI-IFN production by porcine pDC. Our data further indicate that the gE/gI glycoprotein complex suppresses TI-IFN production by pDC, which represents the first alphaherpesvirus factor that suppresses pDC activity. IMPORTANCE Several alphaherpesviruses, including herpes simpex virus, still lack effective vaccines. However, the highly successful Bartha vaccine has contributed substantially to eradication of the porcine alphaherpesvirus pseudorabies virus (PRV) in several countries. The impact of Bartha on the immune response is still poorly understood. Type I interferon (TI-IFN)-producing plasmacytoid dendritic cells (pDC) may play an important role in vaccine development. Here, we show that Bartha elicits a dramatically increased type I interferon (TI-IFN) response in primary porcine pDC compared to wild-type strains. In addition, we found that the gE/gI complex, which is absent in Bartha, inhibits the pDC TI-IFN response. This is the first description of an immune cell type that is differentially affected by Bartha versus wild-type PRV and is the first report describing an alphaherpesvirus protein that inhibits the TI-IFN response by pDC. These data may therefore contribute to the rational design of other alphaherpesvirus vaccines. PMID:28122975

The Pseudorabies Virus Glycoprotein gE/gI Complex Suppresses Type I Interferon Production by Plasmacytoid Dendritic Cells.

PubMed

Lamote, Jochen A S; Kestens, Manon; Van Waesberghe, Cliff; Delva, Jonas; De Pelsmaeker, Steffi; Devriendt, Bert; Favoreel, Herman W

2017-04-01

Plasmacytoid dendritic cells (pDC) play a central role in the antiviral immune response, both in the innate response and in shaping the adaptive response, mainly because of their ability to produce massive amounts of type I interferon (TI-IFN). Here, we report that cells infected with the live attenuated Bartha vaccine strain of porcine alphaherpesvirus pseudorabies virus (PRV) trigger a dramatically increased TI-IFN response by porcine primary pDC compared to cells infected with wild-type PRV strains (Becker and Kaplan). Since Bartha is one of the relatively few examples of a highly successful alphaherpesvirus vaccine, identification of factors that may contribute to its efficacy may provide insights for the rational design of other alphaherpesvirus vaccines. The Bartha vaccine genome displays several mutations compared to the genome of wild-type PRV strains, including a large deletion in the unique short (US) region, encompassing the glycoprotein E (gE), gI, US9, and US2 genes. Using recombinant PRV Becker strains harboring the entire Bartha US deletion or single mutations in the four affected US genes, we demonstrate that the absence of the viral gE/gI complex contributes to the observed increased IFN-α response. Furthermore, we show that the absence of gE leads to an enhanced extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation in pDC, which correlates with a higher TI-IFN production by pDC. In conclusion, the PRV Bartha vaccine strain triggers strongly increased TI-IFN production by porcine pDC. Our data further indicate that the gE/gI glycoprotein complex suppresses TI-IFN production by pDC, which represents the first alphaherpesvirus factor that suppresses pDC activity. IMPORTANCE Several alphaherpesviruses, including herpes simpex virus, still lack effective vaccines. However, the highly successful Bartha vaccine has contributed substantially to eradication of the porcine alphaherpesvirus pseudorabies virus (PRV) in several countries. The impact of Bartha on the immune response is still poorly understood. Type I interferon (TI-IFN)-producing plasmacytoid dendritic cells (pDC) may play an important role in vaccine development. Here, we show that Bartha elicits a dramatically increased type I interferon (TI-IFN) response in primary porcine pDC compared to wild-type strains. In addition, we found that the gE/gI complex, which is absent in Bartha, inhibits the pDC TI-IFN response. This is the first description of an immune cell type that is differentially affected by Bartha versus wild-type PRV and is the first report describing an alphaherpesvirus protein that inhibits the TI-IFN response by pDC. These data may therefore contribute to the rational design of other alphaherpesvirus vaccines. Copyright © 2017 American Society for Microbiology.

Influence of drilling operations on drilling mud gas monitoring during IODP Exp. 338 and 348

NASA Astrophysics Data System (ADS)

Hammerschmidt, Sebastian; Toczko, Sean; Kubo, Yusuke; Wiersberg, Thomas; Fuchida, Shigeshi; Kopf, Achim; Hirose, Takehiro; Saffer, Demian; Tobin, Harold; Expedition 348 Scientists, the

2014-05-01

The history of scientific ocean drilling has developed some new techniques and technologies for drilling science, dynamic positioning being one of the most famous. However, while industry has developed newer tools and techniques, only some of these have been used in scientific ocean drilling. The introduction of riser-drilling, which recirculates the drilling mud and returns to the platform solids and gases from the formation, to the International Ocean Drilling Program (IODP) through the launch of the Japan Agency of Marine Earth-Science and Technology (JAMSTEC) riser-drilling vessel D/V Chikyu, has made some of these techniques available to science. IODP Expedition 319 (NanTroSEIZE Stage 2: riser/riserless observatory) was the first such attempt, and among the tools and techniques used was drilling mud gas analysis. While industry regularly conducts drilling mud gas logging for safety concerns and reservoir evaluation, science is more interested in other components (e.g He, 222Rn) that are beyond the scope of typical mud logging services. Drilling mud gas logging simply examines the gases released into the drilling mud as part of the drilling process; the bit breaks and grinds the formation, releasing any trapped gases. These then circulate within the "closed circuit" mud-flow back to the drilling rig, where a degasser extracts these gases and passes them on to a dedicated mud gas logging unit. The unit contains gas chromatographs, mass spectrometers, spectral analyzers, radon gas analyzers, and a methane carbon isotope analyzer. Data are collected and stored in a database, together with several drilling parameters (rate of penetration, mud density, etc.). This initial attempt was further refined during IODP Expeditions 337 (Deep Coalbed Biosphere off Shimokita), 338 (NanTroSEIZE Stage 3: NanTroSEIZE Plate Boundary Deep Riser 2) and finally 348 (NanTroSEIZE Stage 3: NanTroSEIZE Plate Boundary Deep Riser 3). Although still in its development stage for scientific application, this technique can provide a valuable suite of measurements to complement more traditional IODP shipboard measurements. Here we present unpublished data from IODP Expeditions 338 and 348, penetrating the Nankai Accretionary wedge to 3058.5 meters below seafloor. Increasing mud density decreased degasser efficiency, especially for higher hydrocarbons. Blurring of the relative variations in total gas by depth was observed, and confirmed with comparison to headspace gas concentrations from the cored interval. Theoretically, overpressured zones in the formation can be identified through C2/C3 ratios, but these ratios are highly affected by changing drilling parameters. Proper mud gas evaluations will need to carefully consider the effects of variable drilling parameters when designing experiments and interpreting the data.

A Survey on Personal Data Cloud

PubMed Central

Wang, Jiaqiu; Wang, Zhongjie

2014-01-01

Personal data represent the e-history of a person and are of great significance to the person, but they are essentially produced and governed by various distributed services and there lacks a global and centralized view. In recent years, researchers pay attention to Personal Data Cloud (PDC) which aggregates the heterogeneous personal data scattered in different clouds into one cloud, so that a person could effectively store, acquire, and share their data. This paper makes a short survey on PDC research by summarizing related papers published in recent years. The concept, classification, and significance of personal data are elaborately introduced and then the semantics correlation and semantics representation of personal data are discussed. A multilayer reference architecture of PDC, including its core components and a real-world operational scenario showing how the reference architecture works, is introduced in detail. Existing commercial PDC products/prototypes are listed and compared from several perspectives. Five open issues to improve the shortcomings of current PDC research are put forward. PMID:25165753

Lipid Raft, Regulator of Plasmodesmal Callose Homeostasis.

PubMed

Iswanto, Arya Bagus Boedi; Kim, Jae-Yean

2017-04-03

A bstract: The specialized plasma membrane microdomains known as lipid rafts are enriched by sterols and sphingolipids. Lipid rafts facilitate cellular signal transduction by controlling the assembly of signaling molecules and membrane protein trafficking. Another specialized compartment of plant cells, the plasmodesmata (PD), which regulates the symplasmic intercellular movement of certain molecules between adjacent cells, also contains a phospholipid bilayer membrane. The dynamic permeability of plasmodesmata (PDs) is highly controlled by plasmodesmata callose (PDC), which is synthesized by callose synthases (CalS) and degraded by β-1,3-glucanases (BGs). In recent studies, remarkable observations regarding the correlation between lipid raft formation and symplasmic intracellular trafficking have been reported, and the PDC has been suggested to be the regulator of the size exclusion limit of PDs. It has been suggested that the alteration of lipid raft substances impairs PDC homeostasis, subsequently affecting PD functions. In this review, we discuss the substantial role of membrane lipid rafts in PDC homeostasis and provide avenues for understanding the fundamental behavior of the lipid raft-processed PDC.

Methods and materials for the production of L-lactic acid in yeast

DOEpatents

Hause, Ben [Jordan, MN; Rajgarhia, Vineet [Minnetonka, MN; Suominen, Pirkko [Maple Grove, MN

2009-05-19

Recombinant yeast are provided having, in one aspect, multiple exogenous LDH genes integrated into the genome, while leaving native PDC genes intact. In a second aspect, recombinant yeast are provided having an exogenous LDH gene integrated into its genome at the locus of a native PDC gene, with deletion of the native PDC gene. The recombinant yeast are useful in fermentation process for producing lactic acid.

Comparison of pulsating DC and DC power air-water plasma jet: A method to decrease plume temperature and increase ROS

NASA Astrophysics Data System (ADS)

Liu, K.; Hu, H.; Lei, J.; Hu, Y.; Zheng, Z.

2016-12-01

Most air-water plasma jets are rich in hydroxyl radicals (•OH), but the plasma has higher temperatures, compared to that of pure gas, especially when using air as working gas. In this paper, pulsating direct current (PDC) power was used to excite the air-water plasma jet to reduce plume temperature. In addition to the temperature, other differences between PDC and DC plasma jets are not yet clear. Thus, comparative studies of those plasmas are performed to evaluate characteristics, such as breakdown voltage, temperature, and reactive oxygen species. The results show that the plume temperature of PDC plasma is roughly 5-10 °C lower than that of DC plasma in the same conditions. The •OH content of PDC is lower than that of DC plasma, whereas the O content of PDC plasma is higher. The addition of water leads in an increase in the plume temperature and in the production of •OH with two types of power supplies. The production of O inversely shows a declining tendency with higher water ratio. The most important finding is that the PDC plasma with 100% water ratio achieves lower temperature and more abundant production of •OH and O, compared with DC plasma with 0% water ratio.

Phosphorylation status of pyruvate dehydrogenase distinguishes metabolic phenotypes of cultured rat brain astrocytes and neurons.

PubMed

Halim, Nader D; Mcfate, Thomas; Mohyeldin, Ahmed; Okagaki, Peter; Korotchkina, Lioubov G; Patel, Mulchand S; Jeoung, Nam Ho; Harris, Robert A; Schell, Michael J; Verma, Ajay

2010-08-01

Glucose metabolism in nervous tissue has been proposed to occur in a compartmentalized manner with astrocytes contributing largely to glycolysis and neurons being the primary site of glucose oxidation. However, mammalian astrocytes and neurons both contain mitochondria, and it remains unclear why in culture neurons oxidize glucose, lactate, and pyruvate to a much larger extent than astrocytes. The objective of this study was to determine whether pyruvate metabolism is differentially regulated in cultured neurons versus astrocytes. Expression of all components of the pyruvate dehydrogenase complex (PDC), the rate-limiting step for pyruvate entry into the Krebs cycle, was determined in cultured astrocytes and neurons. In addition, regulation of PDC enzymatic activity in the two cell types via protein phosphorylation was examined. We show that all components of the PDC are expressed in both cell types in culture, but that PDC activity is kept strongly inhibited in astrocytes through phosphorylation of the pyruvate dehydrogenase alpha subunit (PDH alpha). In contrast, neuronal PDC operates close to maximal levels with much lower levels of phosphorylated PDH alpha. Dephosphorylation of astrocytic PDH alpha restores PDC activity and lowers lactate production. Our findings suggest that the glucose metabolism of astrocytes and neurons may be far more flexible than previously believed. (c) 2010 Wiley-Liss, Inc.

Plasmacytoid dendritic cells (PDC) are the major DC subset innately producing cytokines in human lymph nodes.

PubMed

Cox, Karina; North, Margaret; Burke, Michael; Singhal, Hemant; Renton, Sophie; Aqel, Nayef; Islam, Sabita; Knight, Stella C

2005-11-01

Plasmacytoid dendritic cells (PDC) constitute a distinct subset of DC found in human peripheral lymph nodes (LN), but little is known about their function. Cell suspensions were prepared from tumor draining LN (n=20) and control LN (n=11) of women undergoing surgical resection for primary breast cancer and elective surgery for benign conditions, respectively. Using four-color flow cytometry, human leukocyte antigen-DR+ DC subsets were identified phenotypically. The proportions and numbers of cells innately producing interleukin (IL)-4, IL-10, IL-12, and interferon-gamma (IFN-gamma) were also measured from intracellular accumulation of cytokine after blocking with monensin. All flow cytometry data were collected without compensation and were compensated off-line using the Winlist algorithm (Verity software). This package also provided the subtraction program to calculate percentage positive cells and intensity of staining. PDC (CD11c-, CD123+) expressed more cytokines than did myeloid DC (CD11c+) or CD1a+ putative "migratory" DC (P<0.001). LN PDC from patients with a good prognosis (px; n=11) demonstrated a relative increase in IL-12 and IFN-gamma expression (median IL-10:IL-12 ratio=0.78 and median IL-4:IFN-gamma ratio=0.7), and PDC from LN draining poor px cancer (n=9) showed a relative increase in IL-10 and IL-4 expression (median IL-10:IL-12 ratio=1.31 and median IL-4:IFN-gamma ratio=2.6). The difference in IL-4:IFN-gamma expression between good and poor px cancer groups was significant (P<0.05). Thus, PDC innately producing cytokines were identified in cell suspensions from human LN, and the character of PDC cytokine secretion may differ between two breast cancer prognostic groups. We speculate that a shift towards PDC IL-10 and IL-4 expression could promote tumor tolerance in LN draining poor px breast cancer.