Making things difficult in lexical decision: the impact of pseudohomophones and transposed-letter nonwords on frequency and semantic priming effects.

PubMed

Lupker, Stephen J; Pexman, Penny M

2010-09-01

Performance in a lexical decision task is crucially dependent on the difficulty of the word-nonword discrimination. More wordlike nonwords cause not only a latency increase for words but also, as reported by Stone and Van Orden (1993), larger word frequency effects. Several current models of lexical decision making can explain these types of results in terms of a single mechanism, a mechanism driven by the nature of the interactions within the lexicon. In 2 experiments, we replicated Stone and Van Orden's increased frequency effect using both pseudohomophones (e.g., BEEST) and transposed-letter nonwords (e.g., JUGDE) as the more wordlike nonwords. In a 3rd experiment, we demonstrated that simply increasing word latencies without changing the difficulty of the word-nonword discrimination does not produce larger frequency effects. These results are reasonably consistent with many current models. In contrast, neither pseudohomophones nor transposed-letter nonwords altered the size of semantic priming effects across 4 additional experiments, posing a challenge to models that would attempt to explain both nonword difficulty effects and semantic priming effects in lexical decision tasks in terms of a single, lexically driven mechanism. (c) 2010 APA, all rights reserved).

46 CFR 56.25-10 - Flange facings.

Code of Federal Regulations, 2011 CFR

2011-10-01

... (incorporated by reference; see 46 CFR 56.01-2). (b) When bolting class 150 standard steel flanges to flat face cast iron flanges, the steel flange must be furnished with a flat face, and bolting must be in accordance with § 56.25-20 of this part. Class 300 raised face steel flanges may be bolted to class 250...

46 CFR 56.25-10 - Flange facings.

Code of Federal Regulations, 2013 CFR

2013-10-01

... (incorporated by reference; see 46 CFR 56.01-2). (b) When bolting class 150 standard steel flanges to flat face cast iron flanges, the steel flange must be furnished with a flat face, and bolting must be in accordance with § 56.25-20 of this part. Class 300 raised face steel flanges may be bolted to class 250...

46 CFR 56.25-10 - Flange facings.

Code of Federal Regulations, 2012 CFR

2012-10-01

... (incorporated by reference; see 46 CFR 56.01-2). (b) When bolting class 150 standard steel flanges to flat face cast iron flanges, the steel flange must be furnished with a flat face, and bolting must be in accordance with § 56.25-20 of this part. Class 300 raised face steel flanges may be bolted to class 250...

46 CFR 56.25-10 - Flange facings.

Code of Federal Regulations, 2014 CFR

2014-10-01

... (incorporated by reference; see 46 CFR 56.01-2). (b) When bolting class 150 standard steel flanges to flat face cast iron flanges, the steel flange must be furnished with a flat face, and bolting must be in accordance with § 56.25-20 of this part. Class 300 raised face steel flanges may be bolted to class 250...

46 CFR 56.25-10 - Flange facings.

Code of Federal Regulations, 2010 CFR

2010-10-01

... (incorporated by reference; see 46 CFR 56.01-2). (b) When bolting class 150 standard steel flanges to flat face cast iron flanges, the steel flange must be furnished with a flat face, and bolting must be in accordance with § 56.25-20 of this part. Class 300 raised face steel flanges may be bolted to class 250...

Radial pressure flange seal

DOEpatents

Batzer, Thomas H.; Call, Wayne R.

1989-01-01

This invention provides an all metal seal for vacuum or pressure vessels or systems. This invention does not use gaskets. The invention uses a flange which fits into a matching groove. Fluid pressure is applied in a chamber in the flange causing at least one of the flange walls to radially press against a side of the groove creating the seal between the flange wall and the groove side.

Radial pressure flange seal

DOEpatents

Batzer, T.H.; Call, W.R.

1989-01-24

This invention provides an all metal seal for vacuum or pressure vessels or systems. This invention does not use gaskets. The invention uses a flange which fits into a matching groove. Fluid pressure is applied in a chamber in the flange causing at least one of the flange walls to radially press against a side of the groove creating the seal between the flange wall and the groove side. 5 figs.

Making Things Difficult in Lexical Decision: The Impact of Pseudohomophones and Transposed-Letter Nonwords on Frequency and Semantic Priming Effects

ERIC Educational Resources Information Center

Lupker, Stephen J.; Pexman, Penny M.

2010-01-01

Performance in a lexical decision task is crucially dependent on the difficulty of the word-nonword discrimination. More wordlike nonwords cause not only a latency increase for words but also, as reported by Stone and Van Orden (1993), larger word frequency effects. Several current models of lexical decision making can explain these types of…

Photonic Waveguide Choke Joint with Absorptive Loading

NASA Technical Reports Server (NTRS)

Wollack, Edward J. (Inventor); U-Yen, Kongpop (Inventor); Chuss, David T. (Inventor)

2016-01-01

A photonic waveguide choke includes a first waveguide flange member having periodic metal tiling pillars, a dissipative dielectric material positioned within an area between the periodic metal tiling pillars and a second waveguide flange member disposed to be coupled with the first waveguide flange member and in spaced-apart relationship separated by a gap. The first waveguide flange member has a substantially smooth surface, and the second waveguide flange member has an array of two-dimensional pillar structures formed therein.

Fuel cell separator plate with bellows-type sealing flanges

DOEpatents

Louis, G.A.

1984-05-29

A fuel cell separator includes a rectangular flat plate having two unitary upper sealing flanges respectively comprising opposite marginal edges of the plate folded upwardly and back on themselves and two lower sealing flanges respectively comprising the other two marginal edges of the plate folded downwardly and back on themselves. Each of the sealing flanges includes a flat wall spaced from the plate and substantially parallel thereto and two accordion-pleated side walls, one of which interconnects the flat wall with the plate and the other of which steps just short of the plate, these side walls affording resilient compressibility to the sealing flange in a direction generally normal to the plane of the plate. Four corner members close the ends of the sealing flanges. An additional resiliently compressible reinforcing member may be inserted in the passages formed by each of the sealing flanges with the plate.

Fuel cell separator plate with bellows-type sealing flanges

DOEpatents

Louis, George A.

1986-08-05

A fuel cell separator includes a rectangular flat plate having two unitary upper sealing flanges respectively comprising opposite marginal edges of the plate folded upwardly and back on themselves and two lower sealing flanges respectively comprising the other two marginal edges of the plate folded downwardly and back on themselves. Each of the sealing flanges includes a flat wall spaced from the plate and substantially parallel thereto and two accordion-pleated side walls, one of which interconnects the flat wall with the plate and the other of which stops just short of the plate, these side walls affording resilient compressibility to the sealing flange in a directiongenerally normal to the plane of the plate. Four corner members close the ends of the sealing flanges. An additional resiliently compressible reinforcing member may be inserted in the passages formed by each of the sealing flanges with the plate.

76 FR 31585 - Forged Stainless Steel Flanges From India: Notice of Rescission of Antidumping Duty...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-01

... Flanges From India: Notice of Rescission of Antidumping Duty Administrative Review AGENCY: Import... review of the antidumping duty order on forged stainless steel flanges from India. The period of review... administrative review of the antidumping duty order on forged stainless steel flanges from India. See Antidumping...

Stress Analysis of Bolted, Segmented Cylindrical Shells Exhibiting Flange Mating-Surface Waviness

NASA Technical Reports Server (NTRS)

Knight, Norman F., Jr.; Phillips, Dawn R.; Raju, Ivatury S.

2009-01-01

Bolted, segmented cylindrical shells are a common structural component in many engineering systems especially for aerospace launch vehicles. Segmented shells are often needed due to limitations of manufacturing capabilities or transportation issues related to very long, large-diameter cylindrical shells. These cylindrical shells typically have a flange or ring welded to opposite ends so that shell segments can be mated together and bolted to form a larger structural system. As the diameter of these shells increases, maintaining strict fabrication tolerances for the flanges to be flat and parallel on a welded structure is an extreme challenge. Local fit-up stresses develop in the structure due to flange mating-surface mismatch (flange waviness). These local stresses need to be considered when predicting a critical initial flaw size. Flange waviness is one contributor to the fit-up stress state. The present paper describes the modeling and analysis effort to simulate fit-up stresses due to flange waviness in a typical bolted, segmented cylindrical shell. Results from parametric studies are presented for various flange mating-surface waviness distributions and amplitudes.

Shim for sealing transition pieces

DOEpatents

Lacy, Benjamin Paul [Greer, SC; Demiroglu, Mehmet [Troy, NY; Sarawate, Neelesh Nandkumar [Niskayuna, NY

2012-07-24

According to one aspect of the invention, a shim for sealing two adjacent turbine transition pieces is disclosed. The shim includes a circumferential member that includes a first lateral flange and a second lateral flange. Further, the first and second lateral flanges each comprise a tab configured to mate to a first surface plane and the first and second lateral flanges are configured to mate to a second surface plane, wherein the first and second surface planes are substantially parallel. In addition, the shim includes a first flange extending substantially perpendicular from the circumferential member.

Reusable pipe flange covers

DOEpatents

Holden, James Elliott; Perez, Julieta

2001-01-01

A molded, flexible pipe flange cover for temporarily covering a pipe flange and a pipe opening includes a substantially round center portion having a peripheral skirt portion depending from the center portion, the center portion adapted to engage a front side of the pipe flange and to seal the pipe opening. The peripheral skirt portion is formed to include a plurality of circumferentially spaced tabs, wherein free ends of the flexible tabs are formed with respective through passages adapted to receive a drawstring for pulling the tabs together on a back side of the pipe flange.

Silent Flange Coupling Design Used for the Schenck Eddy Current Dynamometer

NASA Astrophysics Data System (ADS)

Schinteie, D.; Croitorescu, V.

2016-11-01

The silent flange used for coupling different machines/systems to an eddy current dynamometer represents one of the modular components each test-bench should use. By introducing a silent flange into a dynamometer, the coupling steps are easier and faster. For an appropriate design, the silent flange was analyzed using dedicated software during different operation procedures and scenarios, for materials that allow easy manufacturing. This study shows that the design for this silent flange model has no danger of failure due to the small deformation and the values for the equivalent stresses. The silent flange coupling is suitable for the dynamometer for his high positioning accuracy, the zero backlash and the fact that there is no motion between the shafts.

Integral flange design program. [procedure for computing stresses

NASA Technical Reports Server (NTRS)

Wilson, J. F.

1974-01-01

An automated interactive flange design program utilizing an electronic desk top calculator is presented. The program calculates the operating and seating stresses for circular flanges of the integral or optional type subjected to internal pressure. The required input information is documented. The program provides an automated procedure for computing stresses in selected flange geometries for comparison to the allowable code values.

Influence of stone content on soil hydraulic properties: experimental investigation and test of existing model concepts

NASA Astrophysics Data System (ADS)

Naseri, Mahyar; Richter, Niels; Iden, Sascha C.; Durner, Wolfgang

2017-04-01

Rock fragments in soil, in this contribution referred to as "stones", play an important role for water flow in the subsurface. To successfully model soil hydraulic processes such as evaporation, redistribution and drainage, an understanding of how stones affect soil hydraulic properties (SHP) is crucial. Past investigations on the role of stones in soil have focused on their influence on the water retention curve (WRC) and on saturated hydraulic conductivity Ks, and have led to some simple theoretical models for the influence of stones on effective SHP. However, studies that measure unsaturated SHP directly, i.e., simultaneously the WRC and hydraulic conductivity curve (HCC) are still missing. Also, studies so far were restricted to low or moderate stone contents of less than 40%. We conducted a laboratory study in which we examined the effect of stone content on effective WRC and HCC of stony soils. Mixtures of soil and stones were generated by substituting background soil with stones in weight fractions between 0% (fine material only) to 100% (pure gravel). Stone sizes were 2-5 mm and 7-15 mm, respectively, and background soils were Sand and Sandy Loam. Packed samples were fully saturated under vacuum and subsequently subjected to evaporation in the laboratory. All experiments were done in three replicates. The soil hydraulic properties were determined by the simplified evaporation method using the UMS HYPROP setup. Questions were whether the applied measurement methodology is applicable to derive the SHP of the mixtures and how the gradual increase of stone content will affect the SHP, particularly the HCC. The applied methodology was successful in identifying effective SHP with a high precision over the full moisture range. WRC and HCC were successfully obtained by HYPROP, even for pure gravel with a size of 7-15 mm. WRCs changed qualitatively in the expected manner, i.e., an increase of stone content reduced porosity and soil water content at all suctions. However, the effect on SHP could not be modelled by assuming stones to be simply impermeable objects that occupy a part of the soil space. This was indicated by a nonlinear increase of the van Genuchten shape parameter α and a decrease of n with increasing gravel content, the latter indicating a widening of the effective pore-size distribution. Saturated conductivity decreased with increasing stone content, but then steeply increased for stone contents > 40%. Unsaturated hydraulic conductivity curves of stone-soil mixtures showed a less pronounced decrease with increasing suction as compared to the pure components, again indicating a widening of the effective pore-size distribution and a nonlinear dependence of the effective unsaturated conductivity on stone content.

Ceramic blade attachment system

DOEpatents

Frey, G.A.; Jimenez, O.D.

1996-12-03

A turbine blade having a preestablished rate of thermal expansion is attached to a turbine flange having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine flange includes a first upstanding flange and a second upstanding flange having a groove formed between them. The turbine flange further includes a recess. Each of the first and second upstanding flanges have a plurality of bores therein. A turbine blade has a first member and a second member positioned in one of the groove and the recess. Each of the first member and the second member have a plurality of bores therein. A pin is positioned in respective ones of the plurality of bores in the first and second upstanding members and the first and second members and attach the blade to the turbine flange. The pin has a preestablished rate of thermal expansion being substantially equal to the rate of thermal expansion of the blade. 4 figs.

Reactor shroud joint

DOEpatents

Ballas, Gary J.; Fife, Alex Blair; Ganz, Israel

1998-01-01

A shroud for a nuclear reactor is described. In one embodiment, the shroud includes first and second shroud sections, and each shroud section includes a substantially cylindrical main body having a first end and a second end. With respect to each shroud section, a flange is located at the main body first end, and the flange has a plurality of bolt openings therein and a plurality of scalloped regions. The first shroud section is welded to the second shroud section, and at least some of the bolt openings in the first shroud section flange align with respective bolt openings in the second shroud section flange. In the event that the onset of inter-granular stress corrosion cracking is ever detected in the weld between the shroud section, bolts are inserted through bolt openings in the first shroud section flange and through aligned bolt openings the second shroud section flange. Each bolt, in one embodiment, has a shank section and first and second threaded end sections. Nuts are threadedly engaged to the threaded end sections and tightened against the respective flanges.

Flange joint system for SRF cavities utilizing high force spring clamps for low particle generation

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

None

A flange joint system for SRF cavities. The flange joint system includes a set of high force spring clamps that produce high force on the simple flanges of Superconducting Radio Frequency (SRF) cavities to squeeze conventional metallic seals. The system establishes the required vacuum and RF-tight seal with minimum particle contamination to the inside of the cavity assembly. The spring clamps are designed to stay within their elastic range while being forced open enough to mount over the flange pair. Upon release, the clamps have enough force to plastically deform metallic seal surfaces and continue to a new equilibrium sprungmore » dimension where the flanges remain held against one another with enough preload such that normal handling will not break the seal.« less

Bureau of Land Management Museum Collections: Select Status Report

DTIC Science & Technology

1998-01-01

Collier , princi- pal investigator, and James W. VanStone, proj-Theodore P. Bank II and Robert Maher are cited ect director, for work at the village of...Western Michi- Knecht, Richard, director, Alutiiq Cultural Cen- gan University, (616) 387-3969 ter, (907) 486-1992 or 486-1942 Gentis, Thierry ...information be submitted. A printout of the permit data was submitted to her Summary of Contacts office. Williams provided completed question- Thierry

Pressure-welded flange assembly provides leaktight seal at reduced bolt loads

NASA Technical Reports Server (NTRS)

Martenson, A. J.

1966-01-01

Vibration resistant flange-connector assembly provides a leaktight seal under reduced bolt loads. The assembly consists of ductile metal plates that are pressure welded between dies mounted in recessed flanges.

Comparison of Measured and Calculated Stresses in Built-up Beams

NASA Technical Reports Server (NTRS)

Levin, L Ross; Nelson, David H

1946-01-01

Web stresses and flange stresses were measured in three built-up beams: one of constant depth with flanges of constant cross-section, one linearly tapered in depth with flanges of constant cross section, and one linearly tapered in depth with tapered flanges. The measured stresses were compared with the calculated stresses obtained by the methods outlined in order to determine the degree of accuracy that may be expected from the stress analysis formulas. These comparisons indicated that the average measured stresses for all points in the central section of the beams did not exceed the average calculated stresses by more than 5 percent. It also indicated that the difference between average measured flange stresses and average calculated flange stresses on the net area and a fully effective web did not exceed 6.1 percent.

Steam separator latch assembly

DOEpatents

Challberg, Roy C.; Kobsa, Irvin R.

1994-01-01

A latch assembly removably joins a steam separator assembly to a support flange disposed at a top end of a tubular shroud in a nuclear reactor pressure vessel. The assembly includes an annular head having a central portion for supporting the steam separator assembly thereon, and an annular head flange extending around a perimeter thereof for supporting the head to the support flange. A plurality of latches are circumferentially spaced apart around the head flange with each latch having a top end, a latch hook at a bottom end thereof, and a pivot support disposed at an intermediate portion therebetween and pivotally joined to the head flange. The latches are pivoted about the pivot supports for selectively engaging and disengaging the latch hooks with the support flange for fixedly joining the head to the shroud or for allowing removal thereof.

Steam separator latch assembly

DOEpatents

Challberg, R.C.; Kobsa, I.R.

1994-02-01

A latch assembly removably joins a steam separator assembly to a support flange disposed at a top end of a tubular shroud in a nuclear reactor pressure vessel. The assembly includes an annular head having a central portion for supporting the steam separator assembly thereon, and an annular head flange extending around a perimeter thereof for supporting the head to the support flange. A plurality of latches are circumferentially spaced apart around the head flange with each latch having a top end, a latch hook at a bottom end thereof, and a pivot support disposed at an intermediate portion therebetween and pivotally joined to the head flange. The latches are pivoted about the pivot supports for selectively engaging and disengaging the latch hooks with the support flange for fixedly joining the head to the shroud or for allowing removal thereof. 12 figures.

46 CFR 56.30-10 - Flanged joints (modifies 104.5.1(a)).

Code of Federal Regulations, 2011 CFR

2011-10-01

...-10 (b), Method 8. Welding neck flanges may be used on any piping provided the flanges are butt-welded..., refer to 46 CFR 56.30-5(b) for requirements. (9) Figure 56.30-10 (b), Method 9. Welding neck flanges may.... ER16DE08.002 Note to Fig. 56.30-10(b): “T” is the nominal pipe wall thickness used. Consult the text of...

Liner mounting assembly

NASA Technical Reports Server (NTRS)

Halila, Ely E. (Inventor)

1994-01-01

A mounting assembly includes an annular supporting flange disposed coaxially about a centerline axis which has a plurality of circumferentially spaced apart supporting holes therethrough. An annular liner is disposed coaxially with the supporting flange and includes a plurality of circumferentially spaced apart mounting holes aligned with respective ones of the supporting holes. Each of a plurality of mounting pins includes a proximal end fixedly joined to the supporting flange through a respective one of the supporting holes, and a distal end disposed through a respective one of the liner mounting holes for supporting the liner to the supporting flange while unrestrained differential thermal movement of the liner relative to the supporting flange.

Fuel cell separator with compressible sealing flanges

DOEpatents

Mientek, A.P.

1984-03-30

A separator for separating adjacent fuel cells in a stack of such cells includes a flat, rectangular, gas-impermeable plate disposed between adjacent cells and having two opposite side margins thereof folded back over one side of the plate to form two first seal flanges and having the other side margins thereof folded back over the opposite side of the plate to form two second seal flanges, each of the seal flanges cooperating with the plate to define a channel in which is disposed a resiliently compressible stack of thin metal sheets. The two first seal flanges cooperate with the electrolyte matrix of one of the cells to form a gas-impermeable seal between an electrode of the one cell and one of two reactant gas manifolds. The second seal flanges cooperate with the electrolyte matrix of the other cell for forming a gas-impermeable seal between an electrode of the other cell and the other of the two reactant gas manifolds. The seal flanges cooperate with the associated compressible stacks of sheets for maintaining a spacing between the plate and the electrolyte matrices while accommodating variation of that spacing.

Reactor shroud joint

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

Ballas, G.J.; Fife, A.B.; Ganz, I.

1998-04-07

A shroud for a nuclear reactor is described. In one embodiment, the shroud includes first and second shroud sections, and each shroud section includes a substantially cylindrical main body having a first end and a second end. With respect to each shroud section, a flange is located at the main body first end, and the flange has a plurality of bolt openings therein and a plurality of scalloped regions. The first shroud section is welded to the second shroud section, and at least some of the bolt openings in the first shroud section flange align with respective bolt openings inmore » the second shroud section flange. In the event that the onset of inter-granular stress corrosion cracking is ever detected in the weld between the shroud section, bolts are inserted through bolt openings in the first shroud section flange and through aligned bolt openings the second shroud section flange. Each bolt, in one embodiment, has a shank section and first and second threaded end sections. Nuts are threadedly engaged to the threaded end sections and tightened against the respective flanges. 4 figs.« less

Reactor shroud joint

DOEpatents

Ballas, G.J.; Fife, A.B.; Ganz, I.

1998-04-07

A shroud for a nuclear reactor is described. In one embodiment, the shroud includes first and second shroud sections, and each shroud section includes a substantially cylindrical main body having a first end and a second end. With respect to each shroud section, a flange is located at the main body first end, and the flange has a plurality of bolt openings therein and a plurality of scalloped regions. The first shroud section is welded to the second shroud section, and at least some of the bolt openings in the first shroud section flange align with respective bolt openings in the second shroud section flange. In the event that the onset of inter-granular stress corrosion cracking is ever detected in the weld between the shroud section, bolts are inserted through bolt openings in the first shroud section flange and through aligned bolt openings the second shroud section flange. Each bolt, in one embodiment, has a shank section and first and second threaded end sections. Nuts are threadedly engaged to the threaded end sections and tightened against the respective flanges. 4 figs.

Fuel cell separator with compressible sealing flanges

DOEpatents

Mientek, Anthony P.

1985-04-30

A separator for separating adjacent fuel cells in a stack of such cells includes a flat, rectangular, gas-impermeable plate disposed between adjacent cells and having two opposite side margins thereof folded back over one side of the plate to form two first seal flanges and having the other side margins thereof folded back over the opposite side of the plate to form two second seal flanges, each of the seal flanges cooperating with the plate to define a channel in which is disposed a resiliently compressible stack of thin metal sheets. The two first seal flanges cooperate with the electrolyte matrix of one of the cells to form a gas-impermeable seal between an electrode of the one cell and one of two reactant gas manifolds. The second seal flanges cooperate with the electrolyte matrix of the other cell for forming a gas-impermeable seal between an electrode of the other cell and the other of the two reactant gas manifolds. The seal flanges cooperate with the associated compressible stacks of sheets for maintaining a spacing between the plate and the electrolyte matrices while accommodating variation of that spacing.

Laser rods with undoped, flanged end-caps for end-pumped laser applications

DOEpatents

Meissner, Helmuth E.; Beach, Raymond J.; Bibeau, Camille; Sutton, Steven B.; Mitchell, Scott; Bass, Isaac; Honea, Eric

1999-01-01

A method and apparatus for achieving improved performance in a solid state laser is provided. A flanged, at least partially undoped end-cap is attached to at least one end of a laserable medium. Preferably flanged, undoped end-caps are attached to both ends of the laserable medium. Due to the low scatter requirements for the interface between the end-caps and the laser rod, a non-adhesive method of bonding is utilized such as optical contacting combined with a subsequent heat treatment of the optically contacted composite. The non-bonded end surfaces of the flanged end-caps are coated with laser cavity coatings appropriate for the lasing wavelength of the laser rod. A cooling jacket, sealably coupled to the flanged end-caps, surrounds the entire length of the laserable medium. Radiation from a pump source is focussed by a lens duct and passed through at least one flanged end-cap into the laser rod.

Improvement of formability of high strength steel sheets in shrink flanging

NASA Astrophysics Data System (ADS)

Hamedon, Z.; Abe, Y.; Mori, K.

2016-02-01

In the shrinkage flanging, the wrinkling tends to occur due to compressive stress. The wrinkling will cause a difficulty in assembling parts, and severe wrinkling may leads to rupture of parts. The shrinkage flange of the ultra-high strength steel sheets not only defects the product by the occurrence of the wrinkling but also causes seizure and wear of the dies and shortens the life of dies. In the present study, a shape of a punch having gradual contact was optimized in order to prevent the wrinkling in shrinkage flanging of ultra-high strength steel sheets. The sheet was gradually bent from the corner of the sheet to reduce the compressive stress. The wrinkling in the shrink flanging of the ultra-high strength steel sheets was prevented by the punch having gradual contact. It was found that the punch having gradual contact is effective in preventing the occurrence of wrinkling in the shrinkage flanging.

Method of fabricating a flow device

DOEpatents

Hale, Robert L.

1978-01-01

This invention is a novel method for fabricating leak-tight tubular articles which have an interior flow channel whose contour must conform very closely with design specifications but which are composed of metal which tends to warp if welded. The method comprises designing two longitudinal half-sections of the article, the half-sections being contoured internally to cooperatively form the desired flow passageway. Each half-section is designed with a pair of opposed side flanges extending between the end flanges and integral therewith. The half-sections are positioned with their various flanges in confronting relation and with elongated metal gaskets extending between the confronting flanges for the length of the array. The gaskets are a deformable metal which is fusion-weldable to the end flanges. The mating side flanges are joined mechanically to deform the gaskets and provide a longitudinally sealed assembly. The portions of the end flanges contiguous with the ends of the gaskets then are welded to provide localized end welds which incorporate ends of the gaskets, thus transversely sealing the assembly. This method of fabrication provides leak-tight articles having the desired precisely contoured flow channels, whereas various conventional methods have been found unsatisfactory.

Effects of bending and heat on the ductility and fracture toughness of flange plate.

DOT National Transportation Integrated Search

2012-05-01

Bridge fabricators for the Texas Department of Transportation (TxDOT) have occasionally experienced the : formation of cracks in flange plate during bending operations, particularly when heat is applied. Bending the : flange plate is necessary for ce...

Closure system

DOEpatents

Hertelendy, N.A.

1987-04-22

A pressure resistant seal for a metallic container is formed between a cylindrical portion having one end open and a cap which seals the open end of the shell. The cap is in the form of a frusto-conical flange which is inserted narrow end first into the open end of the shell and the container is sealed by means of a capping tool which pulls the flange against a die, deforming the flange and forcing the edge of the flange into the wall of the shell. 6 figs.

Closure system

DOEpatents

Hertelendy, Nicholas A [Kennewick, WA

1989-01-01

A pressure resistant seal for a metallic container is formed between a cylindrical portion having one end open and a cap which seals the open end of the shell. The cap is in the form of a frusto-conical flange which is inserted narrow end first into the open end of the shell and the container is sealed by means of a capping tool which pulls the flange against a die, deforming the flange and forcing the edge of the flange into the wall of the shell.

Closure system

DOEpatents

Hertelendy, Nicholas A.

1989-04-04

A pressure resistant seal for a metallic container is formed between a cylindrical portion having one end open and a cap which seals the open end of the shell. The cap is in the form of a frusto-conical flange which is inserted narrow end first into the open end of the shell and the container is sealed by means of a capping tool which pulls the flange against a die, deforming the flange and forcing the edge of the flange into the wall of the shell.

Damped flexible seal

DOEpatents

DuBois, Neil J.; Amaral, Antonio M.

1992-10-27

A damped flexible seal assembly for a torpedo isolates the tailcone thereof rom vibrational energy present in the drive shaft assembly. A pair of outside flanges, each of which include an inwardly facing groove and an O-ring constrained therein, provide a watertight seal against the outer non-rotating surface of the drive shaft assembly. An inside flange includes an outwardly-facing groove and an O-ring constrained therein, and provides a watertight seal against the inner surface of the tail cone. Two cast-in-place elastomeric seals provide a watertight seal between the flanges and further provide a damping barrier between the outside flanges and the inside flanges for damping vibrational energy present in the drive shaft assembly before the energy can reach the tailcone through the seal assembly.

Prevention of crack in stretch flanging process using hot stamping technique

NASA Astrophysics Data System (ADS)

Syafiq, Y. Mohd; Hamedon, Z.; Azila Aziz, Wan; Razlan Yusoff, Ahmad

2017-10-01

Demand for enhancing of passenger safety as well as weight reduction of automobiles has increased the use of high strength steel sheets. As a sheet metal is a lightweight having high strength is suitable for producing automotive parts such as white body panel. The stretch flanging of the high strength steel sheet is a problem due to high springback and easy to crack. This study uses three methods to stretch flange the sheets; using lubricants, shear-edge polishing and hot stamping. The effectiveness of these methods will be measured by comparing the flange length of each methods can achieved. For stretch flange with lubricant and polished sheared edge, the flange length failed to achieve the target 15 mm while hot stamping improved the formability of the sheet and preventing the occurrence of the springback and crack. Hot stamping not only improved formability of the sheet but also transformed the microstructure into martensite thus improve the hardness and the strength of the sheet after been quenched with the dies.

Clamp-mount device

NASA Technical Reports Server (NTRS)

Clark, K. H. (Inventor)

1983-01-01

A clamp-mount device is disclosed for mounting equipment to an associated I-beam and the like structural member of the type having oppositely extending flanges wherein the device comprises a base and a pair of oppositely facing clamping members carried diagonally on the base clamping flanges therebetween and having flange receiving openings facing one another. Lock means are carried diagonally by the base opposite the clamping members locking the flanges in the clamping members. A resilient hub is carried centrally of the base engaging and biasing a back side of the flanges maintaining tightly clamped and facilitating use on vertical as well as horizontal members. The base turns about the hub to receive the flanges within the clamping members. Equipment may be secured to the base by any suitable means such as bolts in openings. Slidable gate latches secure the hinged locks in an upright locking position. The resilient hub includes a recess opening formed in the base and a rubber-like pad carried in this opening being depressably and rotatably carried therein.

Laser rods with undoped, flanged end-caps for end-pumped laser applications

DOEpatents

Meissner, H.E.; Beach, R.J.; Bibeau, C.; Sutton, S.B.; Mitchell, S.; Bass, I.; Honea, E.

1999-08-10

A method and apparatus for achieving improved performance in a solid state laser is provided. A flanged, at least partially undoped end-cap is attached to at least one end of a laserable medium. Preferably flanged, undoped end-caps are attached to both ends of the laserable medium. Due to the low scatter requirements for the interface between the end-caps and the laser rod, a non-adhesive method of bonding is utilized such as optical contacting combined with a subsequent heat treatment of the optically contacted composite. The non-bonded end surfaces of the flanged end-caps are coated with laser cavity coatings appropriate for the lasing wavelength of the laser rod. A cooling jacket, sealably coupled to the flanged end-caps, surrounds the entire length of the laserable medium. Radiation from a pump source is focused by a lens duct and passed through at least one flanged end-cap into the laser rod. 14 figs.

Sectional device handling tool

DOEpatents

Candee, Clark B.

1988-07-12

Apparatus for remotely handling a device in an irradiated underwater environment includes a plurality of tubular sections interconnected end-to-end to form a handling structure, the bottom section being adapted for connection to the device. A support section is connected to the top tubular section and is adapted to be suspended from an overhead crane. Each section is flanged at its opposite ends. Axially retractable bolts in each bottom flange are threadedly engageable with holes in the top flange of an adjacent section, each bolt being biased to its retracted position and retained in place on the bottom flange. Guide pins on each top flange cooperate with mating holes on adjacent bottom flanges to guide movement of the parts to the proper interconnection orientation. Each section carries two hydraulic line segments provided with quick-connect/disconnect fittings at their opposite ends for connection to the segments of adjacent tubular sections upon interconnection thereof to form control lines which are connectable to the device and to an associated control console.

76 FR 8773 - Forged Stainless Steel Flanges From India and Taiwan

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-15

... INTERNATIONAL TRADE COMMISSION [Investigation Nos. 731-TA-639 and 640 (Third Review)] Forged Stainless Steel Flanges From India and Taiwan AGENCY: United States International Trade Commission. ACTION... determine whether revocation of the antidumping duty orders on forged stainless steel flanges from India and...

78 FR 17285 - Airworthiness Directives; The Boeing Company Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-21

... inspections for dirt, loose particles, or blockage of the flanged tube and drain hole for the pressure seals... aft pressure seals; doing repetitive inspections for dirt, loose particles, or blockage of the flanged... AD, do a general visual inspection for dirt, loose particles, and blockage of the flanged tube and...

Vertical bowing measurements, C Reactor

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

DeMers, A.E.

1966-02-18

This report consists of a table which gives the change in height of tube No. 4674 at a specified distance from the inlet flange. Forty-one data points were taken beginning with a distance of 18 inches from the inlet flange and ending with a distance of 36 feet from the inlet flange.

Effect of peripheral irregularities in the temperature field during turbine startups with flange heating along the reduction on the durability of turbine casings

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

Beryland, V.I.; Glyadya, A.A.; Pozhidaev, A.V.

1982-07-01

One method for improving the operating flexibility of 150, 200, and 300 MW steam turbines is heating the flanges of the horizontal casing point during startup, both when cold and before cooling down. A design analysis was conducted of the comparative effectiveness of various heating systems from the standpoint of minimizing both temperature differences across the flange width, as well as the level of related thermal stresses. The effects of flange heating during the entire operating period are discussed.

THE USE OF KF STYLE FLANGES IN LOW PARTICULATE APPLICATIONS

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

Kendziora, K. R.; Angelo, J.; Baffes, C.

As SCRF particle accelerator technology advances the need for “low particulate” and “particle free” vacuum sys-tems becomes greater and greater. In the course of the op-eration of these systems, there comes a time when various instruments have to be temporarily attached for diagnostic purposes: RGAs, leak detectors, and additional pumps. In an effort to make the additions of these instruments easier and more time effective, we propose to use KF style flanges for these types of temporary diagnostic connec-tions. This document will describe the tests used to com-pare the particles generated using the assembly of the, widely accepted for “particlemore » free” use, conflat flange to the proposed KF style flange, and demonstrate that KF flanges produce comparable or even less particles« less

Apparatus and methods for impingement cooling of a side wall of a turbine nozzle segment

DOEpatents

Burdgick, Steven Sebastian

2002-01-01

A gas turbine nozzle segment has outer and inner bands and a vane therebetween. Each band includes a nozzle wall, a side wall, a cover and an impingement plate between the cover and the nozzle wall defining two cavities on opposite sides of the impingement plate. Cooling steam is supplied to one cavity for flow through apertures of the impingement plate to cool the nozzle wall. The side wall of the band and inturned flange define with the nozzle wall an undercut region. The impingement plate has a turned flange welded to the inturned flange. A backing plate overlies the turned flange and aligned apertures are formed through the backing plate and turned flange to direct and focus cooling flow onto the side wall of the nozzle segment.

Endocrinological correlates of male bimaturism in wild Bornean orangutans.

PubMed

Marty, Pascal R; van Noordwijk, Maria A; Heistermann, Michael; Willems, Erik P; Dunkel, Lynda P; Cadilek, Manuela; Agil, Muhammad; Weingrill, Tony

2015-11-01

Among primates, orangutans are unique in having pronounced male bimaturism leading to two fully adult morphs that differ in both physical appearance and behavior. While unflanged males have a female-like appearance, flanged males have the full suite of secondary sexual characteristics, including cheek flanges and a large throat sac. So far, hormonal correlates of arrested development in unflanged males and the expression of secondary sexual characteristics in flanged males have only been studied in zoo-housed individuals. In this study, we investigated fecal androgen and glucocorticoid metabolites as hormonal correlates of male bimaturism in 17 wild adult Bornean orangutans (Pongo pygmaeus) in Central Kalimantan, Indonesia. We predicted and found higher androgen levels in flanged males compared to unflanged males, probably due to ongoing strong competition among flanged males who meet too infrequently to establish a clear linear dominance hierarchy. Furthermore, we found no difference in fecal glucocorticoid metabolite concentrations between flanged and unflanged males, indicating that social stress is unlikely to explain arrested development in unflanged wild orangutans. The only actively developing male in our study showed significantly higher androgen levels during the period of development than later as a fully flanged male. This supports earlier findings from zoo studies that elevated androgen levels are associated with the development of secondary sexual characteristics. © 2015 Wiley Periodicals, Inc.

Effect of tip flange on tip leakage flow of small axial flow fans

NASA Astrophysics Data System (ADS)

Zhang, Li; Jin, Yingzi; Jin, Yuzhen

2014-02-01

Aerodynamic performance of an axial flow fan is closely related to its tip clearance leakage flow. In this paper, the hot-wire anemometer is used to measure the three dimensional mean velocity near the blade tips. Moreover, the filtered N-S equations with finite volume method and RNG k-ɛ turbulence model are adopted to carry out the steady simulation calculation of several fans that differ only in tip flange shape and number. The large eddy simulation and the FW-H noise models are adopted to carry out the unsteady numerical calculation and aerodynamic noise prediction. The results of simulation calculation agree roughly with that of tests, which proves the numerical calculation method is feasible.The effects of tip flange shapes and numbers on the blade tip vortex structure and the characteristics are analyzed. The results show that tip flange of the fan has a certain influence on the characteristics of the fan. The maximum efficiencies for the fans with tip flanges are shifted towards partial flow with respect to the design point of the datum fan. Furthermore, the noise characteristics for the fans with tip flanges have become more deteriorated than that for the datum fan. Tip flange contributes to forming tip vortex shedding and the effect of the half-cylinder tip flange on tip vortex shedding is obvious. There is a distinct relationship between the characteristics of the fan and tip vortex shedding. The research results provide the profitable reference for the internal flow mechanism of the performance optimization of small axial flow fans.

46 CFR 98.30-27 - Connections.

Code of Federal Regulations, 2013 CFR

2013-10-01

... joints and couplings to make a tight seal; (2) Use a bolt in at least every other hole and in no case... (ANSI) standard flange coupling; (3) Use a bolt in each hole of couplings other than ANSI standard flange couplings; (4) Use a bolt in each hole of each permanently connected flange coupling; (5) Use...

46 CFR 98.30-27 - Connections.

Code of Federal Regulations, 2011 CFR

2011-10-01

... joints and couplings to make a tight seal; (2) Use a bolt in at least every other hole and in no case... (ANSI) standard flange coupling; (3) Use a bolt in each hole of couplings other than ANSI standard flange couplings; (4) Use a bolt in each hole of each permanently connected flange coupling; (5) Use...

46 CFR 98.30-27 - Connections.

Code of Federal Regulations, 2012 CFR

2012-10-01

... joints and couplings to make a tight seal; (2) Use a bolt in at least every other hole and in no case... (ANSI) standard flange coupling; (3) Use a bolt in each hole of couplings other than ANSI standard flange couplings; (4) Use a bolt in each hole of each permanently connected flange coupling; (5) Use...

46 CFR 98.30-27 - Connections.

Code of Federal Regulations, 2010 CFR

2010-10-01

... joints and couplings to make a tight seal; (2) Use a bolt in at least every other hole and in no case... (ANSI) standard flange coupling; (3) Use a bolt in each hole of couplings other than ANSI standard flange couplings; (4) Use a bolt in each hole of each permanently connected flange coupling; (5) Use...

Open-ended half-mode substrate integrated waveguide sensor with ground flange for complex permittivity measurement

USDA-ARS?s Scientific Manuscript database

A novel open-ended half-mode substrate integrated waveguide (HMSIW) sensor with ground flange for measuring complex permittivity of liquids, semisolids, and granular and particulate materials is presented. The open-ended HMSIW is designed and fabricated on FR4 substrate. The ground flange was custo...

46 CFR 56.30-10 - Flanged joints (modifies 104.5.1(a)).

Code of Federal Regulations, 2010 CFR

2010-10-01

... 104.5.1(a)). (a) Flanged or butt-welded joints are required for Classes I and I-L piping for nominal... Marine Safety Center. Pressure temperature ratings of the appropriate ANSI/ASME standard must not be... service pressure-temperature ratings for flanges of class 300 and lower, within the temperature...

Damage percolation during stretch flange forming of aluminum alloy sheet

NASA Astrophysics Data System (ADS)

Chen, Zengtao; Worswick, Michael J.; Keith Pilkey, A.; Lloyd, David J.

2005-12-01

A multi-scale finite element (FE)-damage percolation model was employed to simulate stretch flange forming of aluminum alloys AA5182 and AA5754. Material softening and strain gradients were captured using a Gurson-based FE model. FE results were then fed into the so-called damage percolation code, from which the damage development was modelled within measured microstructures. The formability of the stretch flange samples was predicted based upon the onset of catastrophic failure triggered by profuse void coalescence within the measured second-phase particle field. Damage development is quantified in terms of crack and void areal fractions, and compared to metallographic results obtained from interrupted stretch flange specimens. Parametric study is conducted on the effect of void nucleation strain in the prediction of formability of stretch flanges to "calibrate" proper nucleation strains for both alloys.

Computational Investigation of Graphene-Carbon Nanotube-Polymer Composite

NASA Astrophysics Data System (ADS)

Jha, Sanjiv; Roth, Michael; Todde, Guido; Subramanian, Gopinath; Shukla, Manoj; Univ of Southern Mississippi Collaboration; US Army Engineer Research; Development Center 3909 Halls Ferry Road Vicksburg, MS 39180, USA Collaboration

Graphene is a single atom thick two dimensional carbon sheet where sp2 -hybridized carbon atoms are arranged in a honeycomb structure. The functionalization of graphene and carbon nanotubes (CNTs) with polymer is a route for developing high performance nanocomposite materials. We study the interfacial interactions among graphene, CNT, and Nylon 6 polymer using computational methods based on density functional theory (DFT) and empirical force-field. Our DFT calculations are carried out using Quantum-ESPRESSO electronic structure code with van der Waals functional (vdW-DF2), whereas the empirical calculations are performed using LAMMPS with the COMPASS force-field. Our results demonstrated that the interactions between (8,8) CNT and graphene, and between CNT/graphene and Nylon 6 consist mostly of van der Waals type. The computed Young's moduli indicated that the mechanical properties of carbon nanostructures are enhanced by their interactions with polymer. The presence of Stone-Wales (SW) defects lowered the Young's moduli of carbon nanostructures.

Remote controlled vacuum joint closure mechanism

DOEpatents

Doll, D.W.; Hager, E.R.

1984-02-22

A remotely operable and maintainable vacuum joint closure mechanism for a noncircular aperture is disclosed. The closure mechanism includes an extendible bellows coupled at one end to a noncircular duct and at its other end to a flange assembly having sealed grooves for establishing a high vacuum seal with the abutting surface of a facing flange which includes an aperture forming part of the system to be evacuated. A plurality of generally linear arrangements of pivotally coupled linkages and piston combinations are mounted around the outer surface of the duct and aligned along the length thereof. Each of the piston/linkage assemblies is adapted to engage the flange assembly by means of a respective piston and is further coupled to a remote controlled piston drive shaft to permit each of the linkages positioned on a respective flat outer surface of the duct to simultaneously and uniformly displace a corresponding piston and the flange assembly with which it is in contact along the length of the duct in extending the bellows to provide a high vacuum seal between the movable flange and the facing flange. A plurality of latch mechanisms are also pivotally mounted on the outside of the duct. A first end of each of the latch mechanisms is coupled to a remotely controlled latch control shaft for displacing the latch mechanism about its pivot point. In response to the pivoting displacement of the latch mechanism, a second end thereof is displaced so as to securely engage the facing flange and maintain the high vacuum seal established by the displacement of the flange assembly and extension of the bellows without displacing the entire duct.

Armor structures

DOEpatents

Chu, Henry Shiu-Hung [Idaho Falls, ID; Lacy, Jeffrey M [Idaho Falls, ID

2008-04-01

An armor structure includes first and second layers individually containing a plurality of i-beams. Individual i-beams have a pair of longitudinal flanges interconnected by a longitudinal crosspiece and defining opposing longitudinal channels between the pair of flanges. The i-beams within individual of the first and second layers run parallel. The laterally outermost faces of the flanges of adjacent i-beams face one another. One of the longitudinal channels in each of the first and second layers faces one of the longitudinal channels in the other of the first and second layers. The channels of the first layer run parallel with the channels of the second layer. The flanges of the first and second layers overlap with the crosspieces of the other of the first and second layers, and portions of said flanges are received within the facing channels of the i-beams of the other of the first and second layers.

Giardia muris and Giardia duodenalis groups: ultrastructural differences between the trophozoites.

PubMed

Sogayar, M I; Gregório, E A

1989-01-01

Trophozoites of the Giardia muris group from hamsters, domestic rats and mice and of the Giardia duodenalis group from hamsters and domestic rats were examined by transmission electron microscopy. The basic ultrastructure of the trophozoites was similar. Differences were shown in the morphology of the ventrolateral flange of the trophozoites of Giardia muris and Giardia duodenalis groups. Marginal plates are less developed in the species of the Giardia duodenalis group. In this group, the distal extremity of the lateral flange is short and thick and the marginal plate does not penetrate into the distal extremity of the flange. In the Giardia muris group, the ventro-lateral flange is well developed and narrow and the marginal plate penetrates the distal extremity of the flange. The osmiophilic lamella, which accompanies the dorsal surface of the marginal plate is seen only in the Giardia muris group.

Cryogenic Flange and Seal Evaluation

NASA Technical Reports Server (NTRS)

Ramirez, Adrian

2014-01-01

The assembly of flanges, seals, and pipes are used to carry cryogenic fluid from a storage tank to the vehicle at launch sites. However, after a certain amount of cycles these raised face flanges with glass-filled Teflon gaskets have been found to have torque relaxation and are as a result susceptible to cryogenic fluid leakage if not re-torqued. The intent of this project is to identify alternate combinations of flanges and seals which may improve thermal cycle performance and decrease re-torque requirements. The general approach is to design a test fixture to evaluate leak characteristics between spiral and concentric serrations and to test alternate flange and seal combinations. Due to insufficient time, it was not possible to evaluate these different types of combinations for the combination that improved thermal cycle performance the most. However, the necessary drawings for the test fixture were designed and assembled along with the collection of the necessary parts.

49 CFR 179.200-13 - Manway ring or flange, pressure relief device flange, bottom outlet nozzle flange, bottom washout...

Code of Federal Regulations, 2012 CFR

2012-10-01

...) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179..., figure 10, of the AAR Specifications for Tank Cars (IBR, see § 171.7 of this subchapter). (b) The opening...

49 CFR 179.200-13 - Manway ring or flange, pressure relief device flange, bottom outlet nozzle flange, bottom washout...

Code of Federal Regulations, 2014 CFR

2014-10-01

...) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179..., figure 10, of the AAR Specifications for Tank Cars (IBR, see § 171.7 of this subchapter). (b) The opening...

49 CFR 179.200-13 - Manway ring or flange, pressure relief device flange, bottom outlet nozzle flange, bottom washout...

Code of Federal Regulations, 2010 CFR

2010-10-01

... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SPECIFICATIONS FOR TANK CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179..., figure 10, of the AAR Specifications for Tank Cars (IBR, see § 171.7 of this subchapter). (b) The opening...

49 CFR 179.200-13 - Manway ring or flange, pressure relief device flange, bottom outlet nozzle flange, bottom washout...

Code of Federal Regulations, 2013 CFR

2013-10-01

...) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179..., figure 10, of the AAR Specifications for Tank Cars (IBR, see § 171.7 of this subchapter). (b) The opening...

46 CFR 154.528 - Piping joints: Flange type.

Code of Federal Regulations, 2010 CFR

2010-10-01

... and Process Piping Systems § 154.528 Piping joints: Flange type. (a) A flange must be one of the following types: (1) Welding neck. (2) Slip-on. (3) Socket weld. (b) If the piping is designed for a... less; or (3) Welding neck. (c) If the piping is designed for a temperature lower than −55 °C (−67 °F...

Investigation of vacuum properties of CuCrZr alloy for high-heat-load absorber

NASA Astrophysics Data System (ADS)

Shueh, C.; Chan, C. K.; Chang, C. C.; Sheng, I. C.

2017-01-01

The Taiwan Photon Source (TPS) uses high-heat-load (HHL) absorbers to protect downstream ultrahigh-vacuum chambers from overheating. In this work, we propose to use the CuCrZr alloy (ASTM C18150) for the HHL absorber body and the ConFlat® flanges. We use the throughput method to measure the thermal outgassing rate and a helium leak detector to verify the vacuum seal between the CuCrZr alloy and stainless-steel flanges. The measured outgassing rate of the CuCrZr alloy was 5.8×10-10 Pa m/s after 72 h of pumping and decreased to 2.0 × 10-10 Pa m/s after 100 h of pumping. The leak rate through the vacuum seal between a CuCrZr flange and a stainless-steel flange was less than 1 × 10-10 Pa m3/s even after mounting and unmounting the flanges ten times and baking them at 250 °C. These results indicate that CuCrZr alloy is suitable for integrating HHL components with ConFlat® CuCrZr flanges for the absorption of the synchrotron radiation generated by the TPS.

Saddle clamp assembly

NASA Technical Reports Server (NTRS)

Belrose, Charles R. (Inventor)

1994-01-01

A saddle clamp assembly is presented. The assembly is comprised of a hollow cylindrical body centered about a longitudinal axis and being diametrically split into semicircular top and bottom sections. Each section has a pair of connection flanges, at opposite ends, that project radially outward. A pair of bolts are retained on the top section flanges and are threadable into nuts retained on the bottom section flanges. A base member is anchored to a central underside portion of the bottom clamp body section and has a pair of connection tabs positioned beneath the bottom clamp body section connection flanges on opposite sides of the clamp axis. A pair of bolts are retained on the base member connection tabs and are threadable into a pair of nuts retainable on a support structure. The connection tab and connection flanges on each side of the clamp body are axially offset in a manner permitting downward installation/removable tool access to the lower bolts past the connection flanges. An elongated retention tether is used to connect the top clamp body section to the balance of the clamp assembly. This prevents loss of the top clamp body section when it is removed from the bottom clamp body section.

A report on the medieval mining and ore processing complex: Zilan valley, Van, Turkey.

NASA Astrophysics Data System (ADS)

Ateş, Yusuf; Kılıη, Sinan

Literature has records of the use of obsidian that shows the existence of a knowledge base on raw material resources around Lake Van extending to very ancient times. Against this background, very little information can be obtained from literature about accurate location of historical mining activities in the region today. An ancient mining and processing complex, located northwest of the city of Van (Turkey) has been discovered by chance in 2007. The purpose of this article is to describe this historical mining area. The site contains mining structures such as shafts and galleries, and heaves of stone chips indicating some ore enrichment activities taking place there. The XRD and chemical analyses show the samples taken from the ore vein are rich in Manganese (Mn) and Barium (Ba), and it is concluded that the Zilan Valley Mining and Processing Complex was for Pyrolusite (MnO2), Barium or both. The site is being described for the first time in the literature and offers an opportunity to fulfill the gap in literature regarding mining history. The discovery and the description of the site would also have implications in a wide multidisciplinary scientific community, including metallurgy, archeology, and world heritage.

Remote controlled vacuum joint closure mechanism

DOEpatents

Doll, David W.; Hager, E. Randolph

1986-01-01

A remotely operable and maintainable vacuum joint closure mechanism for a noncircular aperture is disclosed. The closure mechanism includes an extendible bellows coupled at one end to a noncircular duct and at its other end to a flange assembly having sealed grooves for establishing a high vacuum seal with the abutting surface of a facing flange which includes an aperture forming part of the system to be evacuated. A plurality of generally linear arrangements of pivotally coupled linkages and piston combinations are mounted around the outer surface of the duct and aligned along the length thereof. Each of the piston/linkage assemblies is adapted to engage the flange assembly by means of a respective piston and is further coupled to a remote controlled piston drive shaft to permit each of the linkages positioned on a respective flat outer surface of the duct to simultaneously and uniformly displace a corresponding piston and the flange assembly with which it is in contact along the length of the duct in extending the bellows to provide a high vacuum seal between the movable flange and the facing flange. A plurality of latch mechanisms are also pivotally mounted on the outside of the duct. A first end of each of the latch mechanisms is coupled to a remotely controlled latch control shaft for displacing the latch mechanism about its pivot point. In response to the pivoting displacement of the latch mechanism, a second end thereof is displaced so as to securely engage the facing flange.

Bulletin of the American Astronomical Society. Volume 36, Number 1, 2004

DTIC Science & Technology

2004-01-01

A. S., Van Malderen, R., Uytterhoeven, K., Davignon, G., Dunham, E. W., Olkin , C. B., Taylor, B. W., Wasserman, L. H., Clancy, K., Person, M. J...Leggett, S. K., Levine, S. E., Moon, D.-S., Olkin , C. B., Osip, D. J., Pasachoff, J. M., Penprase, B. E., Person, M. J., Qu, S., Rayner, J. T., Rob...Moon, D.-S., Buie, M. W., Dunham, E. W., Olkin , C. B., Taylor, B., Kern, S. D., Qu, S., Salyk, C. V., Leggett, S. K., Levine, S. E., and Stone, R. C

Face seal assembly for rotating drum

DOEpatents

Morgan, J. Giles; Rennich, Mark J.; Whatley, Marvin E.

1982-01-01

A seal assembly comprises a tube rotatable about its longitudinal axis and having two longitudinally spaced flanges projecting radially outwardly from the outer surface thereof. Slidably positioned against one of the flanges is a seal ring, and disposed between this seal ring and the other flange are two rings that are forced apart by springs, one of the latter rings being attached to a flexible wall.

49 CFR 587.17 - Construction.

Code of Federal Regulations, 2010 CFR

2010-10-01

... the top edge of the flange and five holes in the bottom flange at a distance of 40 mm (1.6 in) from the bottom edge of the flange. The holes are spaced at 100 mm (3.9 in), 300 mm (11.8 in), 500 mm (19.7 in), 700 mm (27.5 in), 900 mm (35.4 in) horizontally, from either edge of the barrier. All holes are...

The Lateral Stability of Equal-flanged Aluminum-alloy I-beams Subjected to Pure Bending

NASA Technical Reports Server (NTRS)

Dumont, C; Hill, H N

1940-01-01

Equal-flange beams of a special extruded I-section of 27ST aluminum alloy were tested in pure bending. Complete end fixity was not attained. Loading was continued until a definite maximum value had been reached. Tensile tests were made on specimens cut from the flanges and the web of each beam. Compressive stress-strain characteristics were determined by pack compression tests on specimens cut from the flanges. Values computed from an equation previously suggested by one of the authors for the critical stress at which such beams become unstable were found to be in good agreement with values computed from experimentally determined critically bending moments.

Design, analysis, and testing of a metal matrix composite web/flange intersection

NASA Technical Reports Server (NTRS)

Biggers, S. B.; Knight, N. F., Jr.; Moran, S. G.; Olliffe, R.

1992-01-01

An experimental and analytical program to study the local design details of a typical T-shaped web/flange intersection made from a metal matrix composite is described. Loads creating flange bending were applied to specimens having different designs and boundary conditions. Finite element analyses were conducted on models of the test specimens to predict the structural response. The analyses correctly predict failure load, mode, and location in the fillet material in the intersection region of the web and the flange when specimen quality is good. The test program shows the importance of fabrication quality in the intersection region. The full-scale test program that led to the investigation of this local detail is also described.

Schematic construction of flanged nanobearings from double-walled carbon nanotubes.

PubMed

Shenai, Prathamesh Mahesh; Zhao, Yang

2010-08-01

The performance of nanobearings constructed from double walled carbon nanotubes is considered to be crucially dependent on the initial rotational speed. Wearless rotation ceases for a nanobearing operating beyond a certain angular velocity. We propose a new design of nanobearings by manipulation of double walled carbon nanotubes leading to a flanged structure which possesses a built-in hindrance to the intertube oscillation without obstructing rotational motion. Through blocking the possible leakage path for rotational kinetic energy to the intertube oscillatory motion, the flanged bearing lowers its dissipative tendency when set into motion. Using molecular dynamics, it is shown that on account of its distinctive structure, the flanged bearing has superior operating characteristics and a broader working domain.

Nuclear reactor pressure vessel support system

DOEpatents

Sepelak, George R.

1978-01-01

A support system for nuclear reactor pressure vessels which can withstand all possible combinations of stresses caused by a postulated core disrupting accident during reactor operation. The nuclear reactor pressure vessel is provided with a flange around the upper periphery thereof, and the flange includes an annular vertical extension formed integral therewith. A support ring is positioned atop of the support ledge and the flange vertical extension, and is bolted to both members. The plug riser is secured to the flange vertical extension and to the top of a radially outwardly extension of the rotatable plug. This system eliminates one joint through which fluids contained in the vessel could escape by making the fluid flow path through the joint between the flange and the support ring follow the same path through which fluid could escape through the plug risers. In this manner, the sealing means to prohibit the escape of contained fluids through the plug risers can also prohibit the escape of contained fluid through the securing joint.

Development of flange and reticulate wall ingrowths in maize (Zea mays L.) endosperm transfer cells.

PubMed

Monjardino, Paulo; Rocha, Sara; Tavares, Ana C; Fernandes, Rui; Sampaio, Paula; Salema, Roberto; da Câmara Machado, Artur

2013-04-01

Maize (Zea mays L.) endosperm transfer cells are essential for kernel growth and development so they have a significant impact on grain yield. Although structural and ultrastructural studies have been published, little is known about the development of these cells, and prior to this study, there was a general consensus that they contain only flange ingrowths. We characterized the development of maize endosperm transfer cells by bright field microscopy, transmission electron microscopy, and confocal laser scanning microscopy. The most basal endosperm transfer cells (MBETC) have flange and reticulate ingrowths, whereas inner transfer cells only have flange ingrowths. Reticulate and flange ingrowths are mostly formed in different locations of the MBETC as early as 5 days after pollination, and they are distinguishable from each other at all stages of development. Ingrowth structure and ultrastructure and cellulose microfibril compaction and orientation patterns are discussed during transfer cell development. This study provides important insights into how both types of ingrowths are formed in maize endosperm transfer cells.

Quick connect coupling

NASA Technical Reports Server (NTRS)

Sprague, Benny B. (Inventor)

1990-01-01

A coupling device has a transversely arranged, open-end groove in a flange attached to a pipe end. The groove in the flange receives a circumferentially arranged locking flange element on the other coupling member and permits alignment of the bores of the coupling members when the locking flange element is in the open end groove. Upon alignment of the bores of the coupling members, a trigger member is activated to automatically release a spring biased tubular member in one of the coupling members. The tubular member has a conical end which is displaced into the other coupling member to lock the coupling members to one another. A tensioning nut is threadedly movable on a coupling member so as to be moved into tightening engagement with the other coupling member.

Robot Serviced Space Facility

NASA Technical Reports Server (NTRS)

Purves, Lloyd R. (Inventor)

1992-01-01

A robot serviced space facility includes multiple modules which are identical in physical structure, but selectively differing in function. and purpose. Each module includes multiple like attachment points which are identically placed on each module so as to permit interconnection with immediately adjacent modules. Connection is made through like outwardly extending flange assemblies having identical male and female configurations for interconnecting to and locking to a complementary side of another flange. Multiple rows of interconnected modules permit force, fluid, data and power transfer to be accomplished by redundant circuit paths. Redundant modules of critical subsystems are included. Redundancy of modules and of interconnections results in a space complex with any module being removable upon demand, either for module replacement or facility reconfiguration. without eliminating any vital functions of the complex. Module replacement and facility assembly or reconfiguration are accomplished by a computer controlled articulated walker type robotic manipulator arm assembly having two identical end-effectors in the form of male configurations which are identical to those on module flanges and which interconnect to female configurations on other flanges. The robotic arm assembly moves along a connected set or modules by successively disconnecting, moving and reconnecting alternate ends of itself to a succession of flanges in a walking type maneuver. To transport a module, the robot keeps the transported module attached to one of its end-effectors and uses another flange male configuration of the attached module as a substitute end-effector during walking.

High performance fuel element with end seal

DOEpatents

Lee, Gary E.; Zogg, Gordon J.

1987-01-01

A nuclear fuel element comprising an elongate block of refractory material having a generally regular polygonal cross section. The block includes parallel, spaced, first and second end surfaces. The first end surface has a peripheral sealing flange formed thereon while the second end surface has a peripheral sealing recess sized to receive the flange. A plurality of longitudinal first coolant passages are positioned inwardly of the flange and recess. Elongate fuel holes are separate from the coolant passages and disposed inwardly of the flange and the recess. The block is further provided with a plurality of peripheral second coolant passages in general alignment with the flange and the recess for flowing coolant. The block also includes two bypasses for each second passage. One bypass intersects the second passage adjacent to but spaced from the first end surface and intersects a first passage, while the other bypass intersects the second passage adjacent to but spaced from the second end surface and intersects a first passage so that coolant flowing through the second passages enters and exits the block through the associated first passages.

Do flexible acrylic resin lingual flanges improve retention of mandibular complete dentures?

PubMed Central

Ahmed Elmorsy, Ayman Elmorsy; Ahmed Ibraheem, Eman Mostafa; Ela, Alaa Aboul; Fahmy, Ahmed; Nassani, Mohammad Zakaria

2015-01-01

Objectives: The aim of this study was to compare the retention of conventional mandibular complete dentures with that of mandibular complete dentures having lingual flanges constructed with flexible acrylic resin “Versacryl.” Materials and Methods: The study sample comprised 10 completely edentulous patients. Each patient received one maxillary complete denture and two mandibular complete dentures. One mandibular denture was made of conventional heat-cured acrylic resin and the other had its lingual flanges made of flexible acrylic resin Versacryl. Digital force-meter was used to measure retention of mandibular dentures at delivery and at 2 weeks and 45 days following denture insertion. Results: The statistical analysis showed that at baseline and follow-up appointments, retention of mandibular complete dentures with flexible lingual flanges was significantly greater than retention of conventional mandibular dentures (P < 0.05). In both types of mandibular dentures, retention of dentures increased significantly over the follow-up period (P < 0.05). Conclusions: The use of flexible acrylic resin lingual flanges in the construction of mandibular complete dentures improved denture retention. PMID:26539387

Local buckling of composite channel columns

NASA Astrophysics Data System (ADS)

Szymczak, Czesław; Kujawa, Marcin

2018-05-01

The investigation concerns local buckling of compressed flanges of axially compressed composite channel columns. Cooperation of the member flange and web is taken into account here. The buckling mode of the member flange is defined by rotation angle a flange about the line of its connection with the web. The channel column under investigation is made of unidirectional fibre-reinforced laminate. Two approaches to member orthotropic material modelling are performed: the homogenization with the aid of theory of mixture and periodicity cell or homogenization upon the Voigt-Reuss hypothesis. The fundamental differential equation of local buckling is derived with the aid of the stationary total potential energy principle. The critical buckling stress corresponding to a number of buckling half-waves is assumed to be a minimum eigenvalue of the equation. Some numerical examples dealing with columns are given here. The analytical results are compared with the finite element stability analysis carried out by means of ABAQUS software. The paper is focused on a close analytical solution of the critical buckling stress and the associated buckling mode while the web-flange cooperation is assumed.

Test and Analysis of Composite Hat Stringer Pull-off Test Specimens

NASA Technical Reports Server (NTRS)

Li, Jian; OBrien, T. Kevin; Rousseau, Carl Q.

1996-01-01

Hat stringer pull-off tests were performed to evaluate the delamination failure mechanisms in the flange region for a rod-reinforced hat stringer section. A special test fixture was used to pull the hat off the stringer while reacting the pull-off load through roller supports at both stringer flanges. Microscopic examinations of the failed specimens revealed that failure occurred at the ply termination in the flange area where the flange of the stiffener is built up by adding 45/-45 tape plies on the top surface. Test results indicated that the as-manufactured microstructure in the flange region has a strong influence on the delamination initiation and the associated pull-off loads. Finite element models were created for each specimen with a detailed mesh based on micrographs of the critical location. A fracture mechanics approach and a mixed mode delamination criterion were used to predict the onset of delamination and the pull-off load. By modeling the critical local details of each specimen from micrographs, the model was able to accurately predict the hat stringer pull-off loads and replicate the variability in the test results.

Partially integrated exhaust manifold

DOEpatents

Hayman, Alan W; Baker, Rodney E

2015-01-20

A partially integrated manifold assembly is disclosed which improves performance, reduces cost and provides efficient packaging of engine components. The partially integrated manifold assembly includes a first leg extending from a first port and terminating at a mounting flange for an exhaust gas control valve. Multiple additional legs (depending on the total number of cylinders) are integrally formed with the cylinder head assembly and extend from the ports of the associated cylinder and terminate at an exit port flange. These additional legs are longer than the first leg such that the exit port flange is spaced apart from the mounting flange. This configuration provides increased packaging space adjacent the first leg for any valving that may be required to control the direction and destination of exhaust flow in recirculation to an EGR valve or downstream to a catalytic converter.

Method Of Making A Vacuum-Tight Continuous Cable Feedthrough Device

DOEpatents

Bazizi, Kamel Abdel; Haelen, Thomas Eugene; Lobkowicz, Frederick; Slattery, Paul Francis

2001-07-17

A vacuum-tight cable feedthrough device includes a metallic first flange that is penetrated by a slot. Passing through the slot is a flat stripline cable that includes a plurality of conductive signal channels encompassed by a dielectric material on whose upper and lower surfaces is disposed a conductive material includes a ground. The stripline cable is sealed within the slot to provide a substantially vacuum-tight seal between the cable and the first flange. In a preferred embodiment, the cable feedthrough device includes a plurality, at least 16, of stripline cables. In a further preferred embodiment, the device includes a second flange and a bellows sealably connecting the first and second flanges, thereby providing a substantially vacuum-tight, flexible housing for the plurality of cables.

OPERATION HARDTACK. Project 3.3. Shock Loading in Ships from Underwater Bursts and Response of Shipboard Equipment

DTIC Science & Technology

1985-09-01

ke l aBit porn of ceeturlifie (atofer md) Sleeelig Gar Room 1iI ¶1 Fitt’ Natfore eck 7 3IMao hlie 01 A VVi Bolkifuad otiffteel2i 1~ Zn ft ov SIS frst...stiffener flange 33 Too of hull Centerline "R SS A Hull stiffener flange 33 Top of hull Centerline 9 R VM Hull stiffener flange 33 45 dog port from top 45 deg

Wheel inspection system environment.

DOT National Transportation Integrated Search

2008-11-18

International Electronic Machines Corporation (IEM) has developed and is now marketing a state-of-the-art Wheel Inspection System Environment (WISE). WISE provides wheel profile and dimensional measurements, i.e. rim thickness, flange height, flange ...

49 CFR 192.147 - Flanges and flange accessories.

Code of Federal Regulations, 2010 CFR

2010-10-01

... maintain its physical and chemical properties at any temperature to which it is anticipated that it might... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Design of Pipeline Components § 192...

Skin-stiffener interface stresses in composite stiffened panels

NASA Technical Reports Server (NTRS)

Wang, J. T. S.; Biggers, S. B.

1984-01-01

A model and solution method for determining the normal and shear stresses in the interface between the skin and the stiffener attached flange were developed. An efficient, analytical solution procedure was developed and incorporated in a sizing code for stiffened panels. The analysis procedure described provides a means to study the effects of material and geometric design parameters on the interface stresses. These stresses include the normal stress, and the shear stresses in both the longitudinal and the transverse directions. The tendency toward skin/stiffener separation may therefore be minimized by choosing appropriate values for the design variables. The most important design variables include the relative bending stiffnesses of the skin and stiffener attached flange, the bending stiffness of the stiffener web, and the flange width. The longitudinal compressive loads in the flange and skin have significant effects on the interface stresses.

Stress distribution in and equivalent width of flanges of wide, thin-wall steel beams

NASA Technical Reports Server (NTRS)

Winter, George

1940-01-01

The use of different forms of wide-flange, thin-wall steel beams is becoming increasingly widespread. Part of the information necessary for a national design of such members is the knowledge of the stress distribution in and the equivalent width of the flanges of such beams. This problem is analyzed in this paper on the basis of the theory of plane stress. As a result, tables and curves are given from which the equivalent width of any given beam can be read directly for use in practical design. An investigation is given of the limitations of this analysis due to the fact that extremely wide and thin flanges tend to curve out of their plane toward the neutral axis. A summary of test data confirms very satisfactorily the analytical results.

Rib forming tool for tubing

DOEpatents

Rowley, James P.; Lewandowski, Edward F.; Groh, Edward F.

1976-01-01

Three cylindrical rollers are rotatably mounted equidistant from the center of a hollow tool head on radii spaced 120.degree. apart. Each roller has a thin flange; the three flanges lie in a single plane to form an internal circumferential rib in a rotating tubular workpiece. The tool head has two complementary parts with two rollers in one part of the head and one roller in the other part; the two parts are joined by a hinge. A second hinge, located so the rollers are between the two hinges, connects one of the parts to a tool bar mounted in a lathe tool holder. The axes of rotation of both hinges and all three rollers are parallel. A hole exposing equal portions of the three roller flanges is located in the center of the tool head. The two hinges permit the tool head to be opened and rotated slightly downward, taking the roller flanges out of the path of the workpiece which is supported on both ends and rotated by the lathe. The parts of the tool head are then closed on the workpiece so that the flanges are applied to the workpiece and form the rib. The tool is then relocated for forming of the next rib.

Behavior of a tapered hub flange with a bolted flat cover in transient temperature field

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

Sawa, T.; Nakagomi, Y.; Hirose, T.

1996-02-01

When bolted flange connections with gaskets are used in mechanical structures such as pipe connections, bolted covers of casks, and pressure vessels in nuclear and chemical plants and cylinder heads in internal combustion engines, they are usually subjected to transient thermal conditions. An experimental and analytical study was made on a bolted connection subjected to thermal loading. The connection consists of an aluminum alloy tapered hub flange and a flat cover, including a gasket fastened by steel bolts and nuts. Temperature distribution in the connection was measured with thermocouples, and the axial bolt force, the maximum bolt stress, and themore » hub stress were measured by strain gages under a thermal condition that the inner surface of the flanges was heated and the outer surfaces of the flanges and the cover were held at room temperature. Finite difference analysis was made to obtain the temperature distributions in the connection due to a transient thermal condition. This paper demonstrates the method for obtaining an increment in axial bolt force and the maximum bolt stress. In all cases, the analytical results were fairly consistent with the experimental results.« less

Improved design of special boundary elements for T-shaped reinforced concrete walls

NASA Astrophysics Data System (ADS)

Ji, Xiaodong; Liu, Dan; Qian, Jiaru

2017-01-01

This study examines the design provisions of the Chinese GB 50011-2010 code for seismic design of buildings for the special boundary elements of T-shaped reinforced concrete walls and proposes an improved design method. Comparison of the design provisions of the GB 50011-2010 code and those of the American code ACI 318-14 indicates a possible deficiency in the T-shaped wall design provisions in GB 50011-2010. A case study of a typical T-shaped wall designed in accordance with GB 50011-2010 also indicates the insufficient extent of the boundary element at the non-flange end and overly conservative design of the flange end boundary element. Improved designs for special boundary elements of T-shaped walls are developed using a displacement-based method. The proposed design formulas produce a longer boundary element at the non-flange end and a shorter boundary element at the flange end, relative to those of the GB 50011-2010 provisions. Extensive numerical analysis indicates that T-shaped walls designed using the proposed formulas develop inelastic drift of 0.01 for both cases of the flange in compression and in tension.

Critical Initial Flaw Size Analysis

NASA Technical Reports Server (NTRS)

Dawicke, David S.; Raju, Ivatury S.; Cheston, Derrick J.

2008-01-01

An independent assessment was conducted to determine the critical initial flaw size (CIFS) for the flange-to-skin weld in the Ares I-X Upper Stage Simulator (USS). The USS consists of several "tuna can" segments that are approximately 216 inches in diameter, 115 inches tall, and 0.5 inches thick. A 6 inch wide by 1 inch thick flange is welded to the skin and is used to fasten adjacent tuna cans. A schematic of a "tuna can" and the location of the flange-to-skin weld are shown in Figure 1. Gussets (shown in yellow in Figure 1) are welded to the skin and flange every 10 degrees around the circumference of the "tuna can". The flange-to-skin weld is a flux core butt weld with a fillet weld on the inside surface, as illustrated in Figure 2. The welding process may create loss of fusion defects in the weld that could develop into fatigue cracks and jeopardize the structural integrity of the Ares I-X vehicle. The CIFS analysis was conducted to determine the largest crack in the weld region that will not grow to failure within 4 lifetimes, as specified by NASA standard 5001 & 5019 [1].

Clamshell closure for metal drum

DOEpatents

Blanton, Paul S

2014-09-30

Closure ring to retain a lid in contact with a metal drum in central C-section conforming to the contact area between a lid and the rim of a drum and further having a radially inwardly directed flange and a vertically downwardly directed flange attached to the opposite ends of the C-section. The additional flanges reinforce the top of the drum by reducing deformation when the drum is dropped and maintain the lid in contact with the drum. The invention is particularly valuable in transportation and storage of fissile material.

Arrangement for connecting a fiber-reinforced plastic pipe to a stainless steel flange

DOEpatents

Allais, Arnaud [D-30625 Hannover, DE; Hoffmann, Ernst [D-30855 Langenhagen, DE

2008-02-05

Arrangement for connecting a fiber-reinforced plastic pipe (18) to a stainless steel flange (12, 16), in which the end of the fiber-reinforced plastic pipe (18) is accommodated in a ring-shaped groove (12a, 16a) in the flange (12, 16), the groove conforming to the dimensions of the fiber-reinforced plastic pipe (18), where the gap remaining between the end of the fiber-reinforced plastic pipe (18) and the ring-shaped groove (12a, 16a) is filled with a sealant (19).

Variable Spaced Grating (VSG) Snout, Rotator and Rails for use at LLE

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

Mukherjee, S K; Emig, J A; Griffith, L V

2010-01-25

The Variable Spaced Grating (VSG) is a spectrometer snout mounted to an X-Ray Framing Camera (XRFC) through the Unimount flange. This equipment already exists and is used at the University of Rochester, Laboratory for Laser Energetics (LLE) facility. The XRFC and the Unimount flange are designed by LLE. The Tilt Rotator fixture that mounts next to the XRFC and the cart rails are designed by LLNL, and are included in this safety note. The other related components, such as the TIM rails and the Unimount flange, are addressed in a separate safety note, EDSN09-500005-AA. The Multipurpose Spectrometer (MSPEC) and VSGmore » are mounted on the TIM Boat through the cart rails that are very similar in design. The tilt rotator combination with the Unimount flange is also a standard mounting procedure. The later mounting system has been included in this safety note. Figure-1 shows the interface components and the VSG snout. Figure-2 shows the VSG assembly mounted on the Unimount flange. The calibration pointer attachment is shown in place of the snout. There are two types of VSG, one made of 6061-T6 aluminum, weighing approximately 3 pounds, and the other made of 304 stainless steel, weighing approximately 5.5 pounds. This safety note examines the VSG steel design. Specific experiments may require orienting the VSG snout in 90 degrees increment with respect to the Unimount flange. This is done by changing the bolts position on the VSG-main body adapter flange to the Unimount adapter plate. There is no hazard involved in handling the VSG during this procedure as it is done outside the target chamber on the cart rail before installing on the TIM. This safety note addresses the mechanical integrity of the VSG structure, the tilt rotating fixture, the cart rails with handle and their connections. Safety Factors are also calculated for the MSPEC in place of the VSG.« less

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

Schindel, Joshua; Muruganandham, Manickam; Pigge, F. Christopher

Purpose: To present a novel marker-flange, addressing source-reconstruction uncertainties due to the artifacts of a titanium intracavitary applicator used for magnetic resonance imaging (MRI)-guided high-dose-rate (HDR) brachytherapy (BT); and to evaluate 7 different MRI marker agents used for interstitial prostate BT and intracavitary gynecologic HDR BT when treatment plans are guided by MRI. Methods and Materials: Seven MRI marker agents were analyzed: saline solution, Conray-60, copper sulfate (CuSO{sub 4}) (1.5 g/L), liquid vitamin E, fish oil, 1% agarose gel (1 g agarose powder per 100 mL distilled water), and a cobalt–chloride complex contrast (C4) (CoCl{sub 2}/glycine = 4:1). A plastic,more » ring-shaped marker-flange was designed and tested on both titanium and plastic applicators. Three separate phantoms were designed to test the marker-flange, interstitial catheters for prostate BT, and intracavitary catheters for gynecologic HDR BT. T1- and T2-weighted MRI were analyzed for all markers in each phantom and quantified as percentages compared with a 3% agarose gel background. The geometric accuracy of the MR signal for the marker-flange was measured using an MRI-CT fusion. Results: The CuSO{sub 4} and C4 markers on T1-weighted MRI and saline on T2-weighted MRI showed the highest signals. The marker-flange showed hyper-signals of >500% with CuSO{sub 4} and C4 on T1-weighted MRI and of >400% with saline on T2-weighted MRI on titanium applicators. On T1-weighted MRI, the MRI signal inaccuracies of marker-flanges were measured <2 mm, regardless of marker agents, and that of CuSO{sub 4} was 0.42 ± 0.14 mm. Conclusion: The use of interstitial/intracavitary markers for MRI-guided prostate/gynecologic BT was observed to be feasible, providing accurate source pathway reconstruction. The novel marker-flange can produce extremely intense, accurate signals, demonstrating its feasibility for gynecologic HDR BT.« less

Debris protection cover assembly for cable connectors

NASA Technical Reports Server (NTRS)

Yovan, Roger D. (Inventor)

1999-01-01

A protective cover assembly for an end of a cable connector having a cable housing that encloses a plurality of connective pins or sockets and that satisfies all requirements for space applications. A connector body flange is formed at the extremity of a cable and is positioned so that it may register with a corresponding connector body flange on the end of a companion cable to which a connection is to be made, one cable end having cable lead pins and the companion cable end having lead sockets with which the pins register. A latch mechanism having a latch housing is received in the connector body flange and a crank connected to a manually rotatable cap actuates a spring-loaded latch element that is engageable with a connector body flange to secure or to release the cover assembly with the simple twisting motion of the cap, thereby simplifying the task of effecting coupling and decoupling of the cable ends.

Integral isolation valve systems for loss of coolant accident protection

DOEpatents

Kanuch, David J.; DiFilipo, Paul P.

2018-03-20

A nuclear reactor includes a nuclear reactor core comprising fissile material disposed in a reactor pressure vessel having vessel penetrations that exclusively carry flow into the nuclear reactor and at least one vessel penetration that carries flow out of the nuclear reactor. An integral isolation valve (IIV) system includes passive IIVs each comprising a check valve built into a forged flange and not including an actuator, and one or more active IIVs each comprising an active valve built into a forged flange and including an actuator. Each vessel penetration exclusively carrying flow into the nuclear reactor is protected by a passive IIV whose forged flange is directly connected to the vessel penetration. Each vessel penetration carrying flow out of the nuclear reactor is protected by an active IIV whose forged flange is directly connected to the vessel penetration. Each active valve may be a normally closed valve.

Trimming Line Design using New Development Method and One Step FEM

NASA Astrophysics Data System (ADS)

Chung, Wan-Jin; Park, Choon-Dal; Yang, Dong-yol

2005-08-01

In most of automobile panel manufacturing, trimming is generally performed prior to flanging. To find feasible trimming line is crucial in obtaining accurate edge profile after flanging. Section-based method develops blank along section planes and find trimming line by generating loop of end points. This method suffers from inaccurate results for regions with out-of-section motion. On the other hand, simulation-based method can produce more accurate trimming line by iterative strategy. However, due to limitation of time and lack of information in initial die design, it is still not widely accepted in the industry. In this study, new fast method to find feasible trimming line is proposed. One step FEM is used to analyze the flanging process because we can define the desired final shape after flanging and most of strain paths are simple in flanging. When we use one step FEM, the main obstacle is the generation of initial guess. Robust initial guess generation method is developed to handle bad-shaped mesh, very different mesh size and undercut part. The new method develops 3D triangular mesh in propagational way from final mesh onto the drawing tool surface. Also in order to remedy mesh distortion during development, energy minimization technique is utilized. Trimming line is extracted from the outer boundary after one step FEM simulation. This method shows many benefits since trimming line can be obtained in the early design stage. The developed method is successfully applied to the complex industrial applications such as flanging of fender and door outer.

Bottom flange reinforcement in NU I-girders.

DOT National Transportation Integrated Search

2010-08-01

"The 1996 edition of AASHTO Standard Specifications for Highway Bridges stated that nominal confinement reinforcement be placed to enclose prestressing steel in the bottom flange of bridge girders from girder ends to at least a distance eq changed th...

Wheel inspection system environment qualification and validation : final report for public distribution.

DOT National Transportation Integrated Search

2009-03-20

International Electronic Machines Corporation (IEM) has developed and is now marketing a state-of-the-art Wheel Inspection System Environment (WISE). WISE provides wheel profile and dimensional measurements, i.e. rim thickness, flange height, flange ...

Deformation of Extruded Titanium Alloys Under Superplastic Conditions

DTIC Science & Technology

1988-07-01

176mm wide with a flange wall 37mm high x 27mm wide and a central web 122mm wide x 18mm thick. Round-bar test pieces aligned parallel to the principal...directions L, T and ST were extrac- ted from the flange and web as shown in Fig 1; gauge length dimensions were 15mm x 5.5mm diameter for the FST test...ares. in the gauge length. Flange Web X 9 NTIS GFA&I v FL Distribut I oc / A es ’- n:ia or Fig I Position of test pieces in extruded section iste i

Design and Fabrication of Quadrupole Ion Mass Spectrometer for Upper Atmosphere.

DTIC Science & Technology

1981-09-30

34 diameter con-flat flange were T.I.G. welded to the end of each of three bowls. All bowls were then electro- polished, cleaned and sent out to have...plated surface was .0001" to .0002" thick. After gold plating, the hemispheres were mated and T.I.G. welded to form a sphere with a con-flat flange at...Valve Rotatable Conflat to fit k" Swage Lock Weld Adaptors. 5 2 3/4" Conflat Flanges machined to fit Swage Lock unions. 12 10-24 x 2 " Brass Screws necket

Analysis of Bonded Joints Between the Facesheet and Flange of Corrugated Composite Panels

NASA Technical Reports Server (NTRS)

Yarrington, Phillip W.; Collier, Craig S.; Bednarcyk, Brett A.

2008-01-01

This paper outlines a method for the stress analysis of bonded composite corrugated panel facesheet to flange joints. The method relies on the existing HyperSizer Joints software, which analyzes the bonded joint, along with a beam analogy model that provides the necessary boundary loading conditions to the joint analysis. The method is capable of predicting the full multiaxial stress and strain fields within the flange to facesheet joint and thus can determine ply-level margins and evaluate delamination. Results comparing the method to NASTRAN finite element model stress fields are provided illustrating the accuracy of the method.

Radial wedge flange clamp

DOEpatents

Smith, Karl H.

2002-01-01

A radial wedge flange clamp comprising a pair of flanges each comprising a plurality of peripheral flat wedge facets having flat wedge surfaces and opposed and mating flat surfaces attached to or otherwise engaged with two elements to be joined and including a series of generally U-shaped wedge clamps each having flat wedge interior surfaces and engaging one pair of said peripheral flat wedge facets. Each of said generally U-shaped wedge clamps has in its opposing extremities apertures for the tangential insertion of bolts to apply uniform radial force to said wedge clamps when assembled about said wedge segments.

High power, high frequency, vacuum flange

DOEpatents

Felker, B.; McDaniel, M.R.

1993-03-23

An improved waveguide flange is disclosed for high power operation that helps prevent arcs from being initiated at the junctions between waveguide sections. The flanges at the end of the waveguide sections have counter bores surrounding the waveguide tubes. When the sections are bolted together the counter bores form a groove that holds a fully annealed copper gasket. Each counterbore has a beveled step that is specially configured to insure the gasket forms a metal-to-metal vacuum seal without gaps or sharp edges. The resultant inner surface of the waveguide is smooth across the junctions between waveguide sections, and arcing is prevented.

An analysis of pipe flange connections using epoxy adhesives/anaerobic sealant instead of gaskets

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

Sawa, T.; Sasaki, R.; Yoneno, M.

1995-11-01

This paper deals with the strength and the sealing performance of pipe flange connections combining the bonding force of adhesives with the clamping force of bolts. The epoxy adhesives or anaerobic sealants are bonded at the interface partially instead of gaskets in pipe flange connections. The stress distribution in the epoxy adhesives (anaerobic sealant), which governs the sealing performance, and the variations in axial bolt force are analyzed, using an axisymmetrical theory of elasticity, when an internal pressure is applied to a connection in which two pipe flanges are clamped together buy bolts and nuts with an initial clamping forcemore » after being joined by epoxy adhesives or anaerobic sealant. In addition, a method for estimating the strength of the combination connection is demonstrated. Experiments are performed and the analytical results are consistent with the experimental results concerning the variation in axial bolt force and the strength of combination connections. It can be seen that the strength of connections increases with a decrease in the bolt pitch circle diameter. Furthermore, it is seen that the sealing performance of such combination connections in which the interface is bonded partially is improved over that of pipe flange connections with metallic gaskets.« less

Testing and Analysis of Composite Skin/Stringer Debonding Under Multi-Axial Loading

NASA Technical Reports Server (NTRS)

Krueger, Ronald; Cvitkovich, Michael K.; OBrien, T. Kevin; Minguet, Pierre J.

1999-01-01

Damage mechanisms in composite bonded skin/stringer constructions under uniaxial and biaxial (in-plane/out- of-plane) loading conditions were examined. Specimens consisted of a tapered composite flange bonded onto a composite skin. Tests were performed under monotonic loading conditions in tension, three-point bending, and combined tension/bending . For combined tension/bending testing, a unique servohydraulic load frame was used that was capable of applying both in-plane tension and out-of-plane bending loads simultaneously. Specimen edges were examined on the microscope to document the damage occurrence and to identify typical damage patterns. The observations showed that, for all three load cases, failure initiated in the flange, near the flange tip, causing the flange to almost fully debond from the skin. A two-dimensional plane-strain finite element model was developed to analyze the different test cases using a geometrically nonlinear solution. For all three loading conditions, principal stresses exceeded the transverse strength of the material in the flange area. Additionally, delaminations of various lengths were simulated in two locations where delaminations were observed. The analyses showed that unstable delamination propagation is likely to occur in one location at the loads corresponding to matrix ply crack initiation for all three load cases.

'Tool' use by the red-tailed hawk (Buteo jamaicensis)

USGS Publications Warehouse

Ellis, David H.; Brunson, Shawn

1993-01-01

Perhaps the best documented example of regular tool use for a falconiform is the Egyptian Vulture (Neophron percnopterus) striking an Ostrich (Struthio camelus) egg with a stone (J. van Lawick-Goodall and H. van Lawick-Goodall 1966, Nature 212:1468-1469; R.K. Brooke 1979, Ostrich 50:257-258). Another species, the Lammergeier (Gypaetus barbatus), routinely drops bones on stone slabs to gain access to the marrow within (L. Brown and D Amadon 1968, Eagles, hawks and falcons of the world, McGraw-Hill, New York, NY U.S.A.). Some, however, would argue that, because the stone is not manipulated, the bone-dropping Lammergeier is not actually using a tool. Another reported example of tool use is the Ferruginous Hawk (Buteo regalis) that allegedly cast a stone at a human intruder near its nest (C.L. Blair 1981, Raptor Research 15:120).]The following may be yet another example of tool use by a raptor. On 5 June 1985, we observed an adult Red-tailed Hawk (Buteo jamaicensis) soaring low (ca 15 m) over the grass-covered slopes of the Galiuro Mountains in southern Arizona. The bird had, probably just moments before, captured a ca I m snake (probably a glossy snake, Arizona elegans, judging by size, shape and color). When the hawk passed near us, it was holding the snake by both feet near the snake's midpoint. With head elevated and mouth open, the snake appeared intent upon biting the hawk. When the hawk was ca 100 m distant from us, it made several shallow stoops over a scattered group of large boulders. On some (and perhaps all) passes, the bird swept sharply upward as it passed over and nearly collided with a boulder. The centrifugal force associated with this change in direction caused the snake to pendulate below the hawk's talons and strike the boulder. During one pass, we observed the snake's head and tail flipping up behind the hawk after slapping the boulder. Not all swoops were over the same boulder, but one particularly obtrusive (ca 1 m tall) boulder was used at least twice. On the last two swoops, the snake hung limp and apparently lifeless from the hawk's talons After the last swoop, the hawk dropped out of sight into tall grass ca 200 m from our position and presumably ate the snake because we could observe no prey in the hawk's talons when it soared up 13 rain later.If the anvil (not held in the hand) is a tool as well as the hammer (held in the hand), then the Red-tailed Hawk may be added to the short list of raptors that have been known to use tools

26. INTERIOR VIEW WITH CLEANING OF A 12 INCH FLANGE ...

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

26. INTERIOR VIEW WITH CLEANING OF A 12 INCH FLANGE ELBOW CASTING. JAMES CRUMB USED A SWING FRAME GRINDER TO CLEAN (GRIND SEAMS FROM) THIS 'EL.' - Stockham Pipe & Fittings Company, Grey Iron Foundry, 4000 Tenth Avenue North, Birmingham, Jefferson County, AL

Remotely operated pipe connector

DOEpatents

Josefiak, Leonard J.; Cramer, Charles E.

1988-01-01

An apparatus for remotely assembling and disassembling a Graylock type coctor between a pipe and a closure for the pipe includes a base and a receptacle on the base for the closure. The pipe is moved into position vertically above the closure by a suitable positioning device such that the flange on the pipe is immediately adjacent and concentric with the flange on the closure. A moving device then moves two semicircular collars from a position free of the closure to a position such that the interior cam groove of each collar contacts the two flanges. Finally, a tensioning device automatically allows remote tightening and loosening of a nut and bolt assembly on each side of the collar to cause a seal ring located between the flanges to be compressed and to seal the closure. Release of the pipe and the connector is accomplished in the reverse order. Preferably, the nut and bolt assembly includes an elongate shaft portion on which a removable sleeve is located.

Integrated Thermal Insulation System for Spacecraft

NASA Technical Reports Server (NTRS)

Kolodziej, Paul (Inventor); Bull, Jeff (Inventor); Kowalski, Thomas (Inventor); Switzer, Matthew (Inventor)

1998-01-01

An integrated thermal protection system (TPS) for a spacecraft includes a grid that is bonded to skin of the spacecraft, e.g., to support the structural loads of the spacecraft. A plurality of thermally insulative, relatively large panels are positioned on the grid to cover the skin of the spacecraft to which the grid has been bonded. Each panel includes a rounded front edge and a front flange depending downwardly from the front edge. Also, each panel includes a rear edge formed with a rounded socket for receiving the rounded front edge of another panel therein, and a respective rear flange depends downwardly from each rear edge. Pins are formed on the front flanges, and pin receptacles are formed on the rear flanges, such that the pins of a panel mechanically interlock with the receptacles of the immediately forward panel. To reduce the transfer to the skin of heat which happens to leak through the panels to the grid, the grid includes stringers that are chair-shaped in cross-section.

Structural performance of notch damaged steel beams repaired with composite materials

NASA Astrophysics Data System (ADS)

El-Taly, Boshra

2016-06-01

An experimental program and an analytical model using ANSYS program were employed to estimate the structural performance of repaired damaged steel beams using fiber reinforced polymer (FRP) composite materials. The beams were artificially notched in the tension flanges at mid-spans and retrofitted by FRP flexible sheets on the tension flanges and the sheets were extended to cover parts of the beams webs with different heights. Eleven box steel beams, including one intact beam, one notch damaged beam and nine notches damaged beam and retrofitted with composite materials, were tested in two-point loading up to failure. The parameters considered were the FRP type (GFRP and CFRP) and number of layers. The results indicated that bonding CFRP sheets to both of the tension steel flange and part of the webs, instead of the tension flange only, enhances the ultimate load of the retrofitted beams, avoids the occurrence of the debonding and increases the beam ductility. Also the numerical models give acceptable results in comparison with the experimental results.

Caps Seal Boltholes On Vacuum-System Flanges

NASA Technical Reports Server (NTRS)

Roman, Robert F.

1993-01-01

Sealing caps devised for boltholes on vacuum-system flanges. Used in place of leak-prone gaskets, and provide solid metal-to-metal interfaces. Each sealing cap contains square-cut circular groove in which O-ring placed. Mounted on studs protruding into access ports, providing positive seal around each bolthole. Each cap mates directly with surface of flange, in solid metal-to-metal fit, with O-ring completely captured in groove. Assembly immune to misalignment, leakage caused by vibration, and creeping distortion caused by weight of port. O-ring material chosen for resistance to high temperature; with appropriate choice of material, temperature raised to as much as 315 degrees C.

30 CFR 7.100 - Explosion tests.

Code of Federal Regulations, 2014 CFR

2014-07-01

... supply to the injector pump. (v) Establish a preliminary low water level for systems using the wet... inches below the minimum allowable low water level. All entrances in the wet exhaust conditioner which do... reserve water supply to the wet exhaust conditioner, insert flanges, float flanges, and cover plates...

30 CFR 7.100 - Explosion tests.

Code of Federal Regulations, 2012 CFR

2012-07-01

... supply to the injector pump. (v) Establish a preliminary low water level for systems using the wet... inches below the minimum allowable low water level. All entrances in the wet exhaust conditioner which do... reserve water supply to the wet exhaust conditioner, insert flanges, float flanges, and cover plates...

Airborne asbestos exposures associated with gasket and packing replacement: a simulation study of flange and valve repair work and an assessment of exposure variables.

PubMed

Madl, Amy K; Devlin, Kathryn D; Perez, Angela L; Hollins, Dana M; Cowan, Dallas M; Scott, Paul K; White, Katherine; Cheng, Thales J; Henshaw, John L

2015-02-01

A simulation study was conducted to evaluate worker and area exposure to airborne asbestos associated with the replacement of asbestos-containing gaskets and packing materials from flanges and valves and assess the influence of several variables previously not investigated. Additionally, potential of take home exposures from clothing worn during the study was characterized. Our data showed that product type, ventilation type, gasket location, flange or bonnet size, number of flanges involved, surface characteristics, gasket surface adherence, and even activity type did not have a significant effect on worker exposures. Average worker asbestos exposures during flange gasket work (PCME=0.166 f/cc, 12-59 min) were similar to average worker asbestos exposures during valve overhaul work (PCME=0.165 f/cc, 7-76 min). Average 8-h TWA asbestos exposures were estimated to range from 0.010 to 0.062 f/cc. Handling clothes worn during gasket and packing replacement activities demonstrated exposures that were 0.71% (0.0009 f/cc 40-h TWA) of the airborne asbestos concentration experienced during the 5 days of the study. Despite the many variables considered in this study, exposures during gasket and packing replacement occur within a relatively narrow range, are below current and historical occupational exposure limits for asbestos, and are consistent with previously published data. Copyright © 2014 Elsevier Inc. All rights reserved.

Debonding in Composite Skin/Stringer Configurations Under Multi-Axial Loading

NASA Technical Reports Server (NTRS)

Cvitkovich, Michael K.; Krueger, Ronald; OBrien, T.; Minguet, Pierre J.

2004-01-01

The objective of this work was to investigate the damage mechanisms in composite bonded skin/stringer constructions under uniaxial and biaxial (in-plane/out-of-plane) loading conditions as typically experienced by aircraft crown fuselage panels. The specimens for all tests were identical and consisted of a tapered composite flange, representing a stringer or frame, bonded onto a composite skin. Tests were performed under monotonic loading conditions in tension, three-point bending, and combined tension/bending to evaluate the debonding mechanisms between the skin and the bonded stringer. For combined tension/bending testing, a unique servohydraulic load frame was used that was capable of applying both loads simultaneously. Microscopic investigations of the specimen edges were used to document the damage occurrence and to identify typical damage patterns. The observations showed that, for all three load cases, failure initiated in the flange near the flange tip causing the flange to almost fully debond from the skin. A two-dimensional plain-strain finite element model was developed to analyze the different test cases using a geometrically nonlinear solution. For all three loading conditions, principal stresses exceeded the transverse strength of the material in the flange area. Additionally, delaminations of various lengths were simulated in the locations where delaminations were experimentally observed. The analyses showed that unstable delamination propagation is likely to occur at the loads corresponding to matrix ply crack initiation for all three loadings.

Investigation of flange failures in falsework cap and sill beams : recommendations for the design of beams and posts in bridge falsework.

DOT National Transportation Integrated Search

2008-12-01

Recent field observations in bridge falsework identified potential deficiencies in the design of falsework resulting in : localized bending in sill and cap beam flanges and lateral buckling in other beams. Possible limits states associated with : the...

46 CFR 98.30-27 - Connections.

Code of Federal Regulations, 2014 CFR

2014-10-01

... other hole and in no case less than four bolts in each temporary connection utilizing an American National Standards Institute (ANSI) standard flange coupling; (3) Use a bolt in each hole of couplings other than ANSI standard flange couplings; (4) Use a bolt in each hole of each permanently connected...

76 FR 67594 - Airworthiness Directives; General Electric Company Turboshaft Engines

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-02

... mounting flanges due to stress- corrosion. This AD also requires the installation of a collar kit over the... prompted by reports of 47 fuel filter differential pressure switches found with stress-corrosion cracking... bending stress to the aluminum mounting flanges of the switch. This bending stress, coupled with...

49 CFR 178.345-1 - General requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) All specification requirements are minimum requirements. (c) Definitions. See § 178.320(a) for the... flange, or by a fillet weld joining the tank shell to a flange shaped to fit the shell contour. (d) A... be constructed with the cargo tanks made to the same specification or to different specifications...

46 CFR 61.20-18 - Examination requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... fitted) and propeller designed in accordance with American Bureau of Shipping standards to reduce stress... visual inspection of the entire shaft. (c) On tailshafts with a propeller fitted to the shaft by means of a coupling flange, the flange, the fillet at the propeller end, and each coupling bolt must be...

46 CFR 61.20-18 - Examination requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... fitted) and propeller designed in accordance with American Bureau of Shipping standards to reduce stress... visual inspection of the entire shaft. (c) On tailshafts with a propeller fitted to the shaft by means of a coupling flange, the flange, the fillet at the propeller end, and each coupling bolt must be...

46 CFR 61.20-18 - Examination requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... fitted) and propeller designed in accordance with American Bureau of Shipping standards to reduce stress... visual inspection of the entire shaft. (c) On tailshafts with a propeller fitted to the shaft by means of a coupling flange, the flange, the fillet at the propeller end, and each coupling bolt must be...

46 CFR 61.20-18 - Examination requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... fitted) and propeller designed in accordance with American Bureau of Shipping standards to reduce stress... visual inspection of the entire shaft. (c) On tailshafts with a propeller fitted to the shaft by means of a coupling flange, the flange, the fillet at the propeller end, and each coupling bolt must be...

46 CFR 61.20-18 - Examination requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... fitted) and propeller designed in accordance with American Bureau of Shipping standards to reduce stress... visual inspection of the entire shaft. (c) On tailshafts with a propeller fitted to the shaft by means of a coupling flange, the flange, the fillet at the propeller end, and each coupling bolt must be...

Development of structural test articles from magnesium-lithium and beryllium

NASA Technical Reports Server (NTRS)

Alario, R.

1969-01-01

Study on the fabrication and testing of a magnesium-lithium box beam shows the formability and machinability characteristics of that alloy to be excellent. Results of forming tests for shrink and stretch flanges show values for both flange heights that may be used in future beryllium design.

Study of The Effect of Draw-bead Geometry on Stretch Flange Formability

NASA Astrophysics Data System (ADS)

Orlov, O. S.; Winkler, S. L.; Worswick, M. J.; Lloyd, D. J.; Finn, M. J.

2004-06-01

A fully instrumented stretch flange press equipped with a back-up punch and draw-beads near the specimen cutout area is simulated. The utilization of different draw-bead geometries is examined numerically to determine the restraining forces, strains and amount of damage generated in stretch flanges during forming. Simulations of the forming process are conducted for 1mm AA5182 sheets with circular cutouts. The damage evolution with the deformed specimens is investigated using the explicit dynamic finite element code, LS-DYNA, with a modified Gurson-based material model. It was found that double draw-beads can provide the same amount of restraining force as single draw-beads, but at reduced levels of damage.

Boron epoxy rocket motor case program

NASA Technical Reports Server (NTRS)

Stang, D. A.

1971-01-01

Three 28-inch-diameter solid rocket motor cases were fabricated using 1/8 inch wide boron/epoxy tape. The cases had unequal end closures (4-1/8-inch-diameter forward flanges and 13-inch-diameter aft flanges) and metal attachment skirts. The flanges and skirts were titanium 6Al-4V alloy. The original design for the first case was patterned after the requirements of the Applications Technology Satellite apogee kick motor. The second and third cases were designed and fabricated to approximate the requirements of a small Applications Technology Satellite apogee kick motor. The program demonstrated the feasibility of designing and fabricating large-scale filament-wound solid propellant rocket motor cases with boron/epoxy tape.

Turbine disc sealing assembly

DOEpatents

Diakunchak, Ihor S.

2013-03-05

A disc seal assembly for use in a turbine engine. The disc seal assembly includes a plurality of outwardly extending sealing flange members that define a plurality of fluid pockets. The sealing flange members define a labyrinth flow path therebetween to limit leakage between a hot gas path and a disc cavity in the turbine engine.

29 CFR 1915.134 - Abrasive wheels.

Code of Federal Regulations, 2012 CFR

2012-07-01

... shall be so mounted as to maintain proper alignment with the wheel, and the guard and its fastenings... safety flanges are required, they shall be used only with wheels designed to fit the flanges. Only safety... wheels shall fit freely on the spindle and shall not be forced on. The spindle nut shall be tightened...

29 CFR 1915.134 - Abrasive wheels.

Code of Federal Regulations, 2013 CFR

2013-07-01

... shall be so mounted as to maintain proper alignment with the wheel, and the guard and its fastenings... safety flanges are required, they shall be used only with wheels designed to fit the flanges. Only safety... wheels shall fit freely on the spindle and shall not be forced on. The spindle nut shall be tightened...

29 CFR 1915.134 - Abrasive wheels.

Code of Federal Regulations, 2014 CFR

2014-07-01

... shall be so mounted as to maintain proper alignment with the wheel, and the guard and its fastenings... safety flanges are required, they shall be used only with wheels designed to fit the flanges. Only safety... wheels shall fit freely on the spindle and shall not be forced on. The spindle nut shall be tightened...

DRAFT One Year Extension of the Short-Term National Product Waiver for Stainless Steel Nuts and Bolts used in Pipe Couplings, Restraints, Joints, Flanges and Saddles for State Revolving Fund Projects

EPA Pesticide Factsheets

DRAFT one year extension of the short-term national product waiver for stainless steel nuts and bolts used in pipe couplings, restraints, joints, flanges and saddles for State Revolving Fund projects.

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

Groenendaal, J.C. Jr.; Anemone, J.J.

This patent describes low pressure steam turbine apparatus having inner and outer cylinders, the outer cylinder having a support shelf, and inner cylinder support means for providing flexible support of the inner cylinder on the outer cylinder. It comprises: a horizontal joint flange and at least one support foot integrally connected thereto which projects substantially radially outward form the horizontal joint flange.

Simplified failure sequence evaluation of reactor pressure vessel head corroding in-core instrumentation assembly

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

McVicker, J.P.; Conner, J.T.; Hasrouni, P.N.

1995-11-01

In-Core Instrumentation (ICI) assemblies located on a Reactor Pressure Vessel Head have a history of boric acid leakage. The acid tends to corrode the nuts and studs which fasten the flanges of the assembly, thereby compromising the assembly`s structural integrity. This paper provides a simplified practical approach in determining the likelihood of an undetected progressing assembly stud deterioration, which would lead to a catastrophic loss of reactor coolant. The structural behavior of the In-Core Instrumentation flanged assembly is modeled using an elastic composite section assumption, with the studs transmitting tension and the pressure sealing gasket experiencing compression. Using the abovemore » technique, one can calculate the flange relative deflection and the consequential coolant loss flow rate, as well as the stress in any stud. A solved real life example develops the expected failure sequence and discusses the exigency of leak detection for safe shutdown. In the particular case of Calvert Cliffs Nuclear Power Plant (CCNPP) it is concluded that leak detection occurs before catastrophic failure of the ICI flange assembly.« less

Gender differences in the anatomy of the distal femur.

PubMed

Gillespie, R J; Levine, A; Fitzgerald, S J; Kolaczko, J; DeMaio, M; Marcus, R E; Cooperman, D R

2011-03-01

Recently, gender-specific designs of total knee replacement have been developed to accommodate anatomical differences between males and females. We examined a group of male and female distal femora matched for age and height, to determine if there was a difference in the aspect ratio (mediolateral distance versus anteroposterior distance) and the height of the anterior flange between the genders. The Hamann-Todd Collection provided 1207 skeletally mature cadaver femora. The femoral length, the anteroposterior height, height of the lateral and medial flanges and the mediolateral width were measured in all the specimens. The mechanical axis of the femur, the cut articular width and the aspect ratio were assessed. Statistical analysis of the effect of gender upon the aspect ratio and the lateral and medial flanges was undertaken, controlling for age, height and race. The mean aspect ratio of male femora was 1.21 (SD 0.07) and of female femora it was 1.16 (SD 0.06) (p < 0.001). There was no significant difference between male and female specimens in the mean size of the lateral flange (6.57 mm (SD 2.57) and 7.02 mm (SD 2.36), respectively; p = 0.099) or of the medial flange (3.03 mm (SD 2.47) and 3.56 mm (SD 2.32), respectively; p = 0.67). Future work in the design of knee prostheses should take into account the overall variability of the anatomy of the distal femur.

75 FR 1536 - Airworthiness Directives; The Boeing Company Model 737-600, -700, and -800 Series Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-12

... stringers of the wing center section for drill starts, and applicable related investigative and corrective actions. This AD results from drill starts being found on the free flange of the lower stringers of the... this AD to prevent cracks from propagating from drill starts in the free flange, vertical web, and...

33 CFR 156.130 - Connection.

Code of Federal Regulations, 2012 CFR

2012-07-01

... material in joints and couplings to ensure a leak-free seal; (2) Use a bolt in at least every other hole... chapter; (3) Use a bolt in each hole in each temporary bolted connection that uses a flange other than one that meets ANSI standards; (4) Use a bolt in each hole of each permanently connected flange; (5) Use...

33 CFR 156.130 - Connection.

Code of Federal Regulations, 2011 CFR

2011-07-01

... material in joints and couplings to ensure a leak-free seal; (2) Use a bolt in at least every other hole... chapter; (3) Use a bolt in each hole in each temporary bolted connection that uses a flange other than one that meets ANSI standards; (4) Use a bolt in each hole of each permanently connected flange; (5) Use...

33 CFR 156.130 - Connection.

Code of Federal Regulations, 2014 CFR

2014-07-01

... material in joints and couplings to ensure a leak-free seal; (2) Use a bolt in at least every other hole... chapter; (3) Use a bolt in each hole in each temporary bolted connection that uses a flange other than one that meets ANSI standards; (4) Use a bolt in each hole of each permanently connected flange; (5) Use...

33 CFR 156.130 - Connection.

Code of Federal Regulations, 2013 CFR

2013-07-01

... material in joints and couplings to ensure a leak-free seal; (2) Use a bolt in at least every other hole... chapter; (3) Use a bolt in each hole in each temporary bolted connection that uses a flange other than one that meets ANSI standards; (4) Use a bolt in each hole of each permanently connected flange; (5) Use...

40 CFR 264.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

Code of Federal Regulations, 2014 CFR

2014-07-01

... liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other... heavy liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other connectors. (a) Pumps and valves in heavy liquid service, pressure relief devices in light liquid...

40 CFR 265.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

Code of Federal Regulations, 2011 CFR

2011-07-01

... liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other... and valves in heavy liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other connectors. (a) Pumps and valves in heavy liquid service, pressure relief...

40 CFR 265.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

Code of Federal Regulations, 2012 CFR

2012-07-01

... liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other... and valves in heavy liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other connectors. (a) Pumps and valves in heavy liquid service, pressure relief...

40 CFR 265.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

Code of Federal Regulations, 2013 CFR

2013-07-01

... liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other... and valves in heavy liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other connectors. (a) Pumps and valves in heavy liquid service, pressure relief...

40 CFR 264.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

Code of Federal Regulations, 2011 CFR

2011-07-01

... liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other... heavy liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other connectors. (a) Pumps and valves in heavy liquid service, pressure relief devices in light liquid...

40 CFR 264.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

Code of Federal Regulations, 2012 CFR

2012-07-01

... liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other... heavy liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other connectors. (a) Pumps and valves in heavy liquid service, pressure relief devices in light liquid...

40 CFR 265.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

Code of Federal Regulations, 2014 CFR

2014-07-01

... liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other... and valves in heavy liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other connectors. (a) Pumps and valves in heavy liquid service, pressure relief...

40 CFR 264.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

Code of Federal Regulations, 2013 CFR

2013-07-01

... liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other... heavy liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other connectors. (a) Pumps and valves in heavy liquid service, pressure relief devices in light liquid...

33 CFR 156.130 - Connection.

Code of Federal Regulations, 2010 CFR

2010-07-01

... material in joints and couplings to ensure a leak-free seal; (2) Use a bolt in at least every other hole... chapter; (3) Use a bolt in each hole in each temporary bolted connection that uses a flange other than one that meets ANSI standards; (4) Use a bolt in each hole of each permanently connected flange; (5) Use...

Use of a bite registration vinyl polysiloxane material to identify denture flange overextension and/or excessive border thickness in removable prosthodontics.

PubMed

Haeberle, C Brent; Abreu, Amara; Metzler, Kurt

2015-01-01

Vinyl polysiloxane (VPS) has multiple applications in prosthodontics. This article describes how a bite registration fast-set VPS material was used to identify length overextension and/or excessive border thickness of denture flanges. In addition, the advantages of VPS over conventional materials are presented.

17. "Concrete Bridge Over Salt River, Port Kenyon, Humboldt County, ...

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

17. "Concrete Bridge Over Salt River, Port Kenyon, Humboldt County, California, A.J. Logan, County Surveyor, H.J. Brunnier, Consulting Engineer, March 7, 1919," showing plan of bars in top flange, elevation of girder reinforcement, plan of bars in bottom flange - Salt River Bridge, Spanning Salt River at Dillon Road, Ferndale, Humboldt County, CA

49 CFR 215.103 - Defective wheel.

Code of Federal Regulations, 2012 CFR

2012-10-01

... less; (d) A wheel rim, flange, plate, or hub area on the car has a crack or break; (e) A wheel on the... 49 Transportation 4 2012-10-01 2012-10-01 false Defective wheel. 215.103 Section 215.103... § 215.103 Defective wheel. A railroad may not place or continue in service a car, if— (a) A wheel flange...

49 CFR 215.103 - Defective wheel.

Code of Federal Regulations, 2011 CFR

2011-10-01

... less; (d) A wheel rim, flange, plate, or hub area on the car has a crack or break; (e) A wheel on the... 49 Transportation 4 2011-10-01 2011-10-01 false Defective wheel. 215.103 Section 215.103... § 215.103 Defective wheel. A railroad may not place or continue in service a car, if— (a) A wheel flange...

Tire/wheel concept

NASA Technical Reports Server (NTRS)

Harper, P. M., Sr. (Inventor)

1981-01-01

A tire and wheel assembly is disclosed in which a low profile pneumatic tire (having sidewalls which deflect inwardly under load) and a wheel (having a rim featuring a narrow central channel and extended rim flanges) form the combination. The extended rim flanges support the tire sidewalls under static and dynamic loading conditions to produce a combination particularly suited to aircraft applications.

49 CFR 215.103 - Defective wheel.

Code of Federal Regulations, 2010 CFR

2010-10-01

... less; (d) A wheel rim, flange, plate, or hub area on the car has a crack or break; (e) A wheel on the... 49 Transportation 4 2010-10-01 2010-10-01 false Defective wheel. 215.103 Section 215.103... § 215.103 Defective wheel. A railroad may not place or continue in service a car, if— (a) A wheel flange...

49 CFR 215.103 - Defective wheel.

Code of Federal Regulations, 2014 CFR

2014-10-01

... less; (d) A wheel rim, flange, plate, or hub area on the car has a crack or break; (e) A wheel on the... 49 Transportation 4 2014-10-01 2014-10-01 false Defective wheel. 215.103 Section 215.103... § 215.103 Defective wheel. A railroad may not place or continue in service a car, if— (a) A wheel flange...

49 CFR 215.103 - Defective wheel.

Code of Federal Regulations, 2013 CFR

2013-10-01

... less; (d) A wheel rim, flange, plate, or hub area on the car has a crack or break; (e) A wheel on the... 49 Transportation 4 2013-10-01 2013-10-01 false Defective wheel. 215.103 Section 215.103... § 215.103 Defective wheel. A railroad may not place or continue in service a car, if— (a) A wheel flange...

49 CFR 179.300-8 - Tank heads.

Code of Federal Regulations, 2010 CFR

2010-10-01

...-110A tanks shall have fusion-welded heads formed concave to pressure. Heads for fusion welding shall be... one heat so as to provide a straight flange at least 11/2 inches long. The thickness shall not be less... shell. They must be one piece, hot formed in one heat so as to provide a straight flange at least 4...

[William Cheselden (1688-1752) and Gerard van der Gucht (1695-1776). Surgical technique, the art of printed images and controversy in the urology book of the XVIII century].

PubMed

Gómiz León, Juan José

2009-11-01

We review the printed work of the English anatomist and surgeon William Cheselden, with special attention to the chalcographic engravings which illustrated it, mainly those by Gerard van der Gucht and the miniaturist Jacob Schijnvoet, vendicating the valuable collaboration of illustrators and printers and their essential figurative contribution to explain the texts and make them easier to understand for the reader. These images were as important as the texts and contributed considerable artistic value to the work. Likewise, we present the bitter controversy caused in the English medical-surgical society of the time, most especially in the lithotomist or "urology" community, by the publication of the work entitled "The High Operation for the Stone"by W. Cheselden. The publication coincided chronologically with the second edition of "Lithotomia Douglassiana" by John Douglas, and the scathing criticism hurled against Cheselden, one of the prime examples of which was the publication of the book entitled "Lithotomus Castratus"; in the book, both works were revised meticulously by its author, collated, analysed in detail and compared against each other, publically indicating that Cheselden plagiarised Douglas.

46 CFR 56.30-10 - Flanged joints (modifies 104.5.1(a)).

Code of Federal Regulations, 2013 CFR

2013-10-01

... addition of a strength fillet weld of the size as shown, may be used in Class I systems not exceeding 750... buttwelding flanges must be provided. For Class II piping systems, the size of the strength fillet may be... void spaces is desirable. For systems of Class II, the size of the strength fillet may be limited to a...

46 CFR 56.30-10 - Flanged joints (modifies 104.5.1(a)).

Code of Federal Regulations, 2014 CFR

2014-10-01

... addition of a strength fillet weld of the size as shown, may be used in Class I systems not exceeding 750... buttwelding flanges must be provided. For Class II piping systems, the size of the strength fillet may be... void spaces is desirable. For systems of Class II, the size of the strength fillet may be limited to a...

46 CFR 56.30-10 - Flanged joints (modifies 104.5.1(a)).

Code of Federal Regulations, 2012 CFR

2012-10-01

... addition of a strength fillet weld of the size as shown, may be used in Class I systems not exceeding 750... buttwelding flanges must be provided. For Class II piping systems, the size of the strength fillet may be... void spaces is desirable. For systems of Class II, the size of the strength fillet may be limited to a...

Scattering of E Polarized Plane Wave by Rectangular Cavity With Finite Flanges

NASA Astrophysics Data System (ADS)

Vinogradova, Elena D.

2017-11-01

The rigorous Method of Regularization is implemented for accurate analysis of wave scattering by rectangular cavity with finite flanges. The solution is free from limitations on problem parameters. The calculation of the induced surface current, bistatic radar cross section (RCS) and frequency dependence of monostatic RCS are performed with controlled accuracy in a wide frequency band.

40 CFR 264.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other... heavy liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and...

An analytical model of a curved beam with a T shaped cross section

NASA Astrophysics Data System (ADS)

Hull, Andrew J.; Perez, Daniel; Cox, Donald L.

2018-03-01

This paper derives a comprehensive analytical dynamic model of a closed circular beam that has a T shaped cross section. The new model includes in-plane and out-of-plane vibrations derived using continuous media expressions which produces results that have a valid frequency range above those available from traditional lumped parameter models. The web is modeled using two-dimensional elasticity equations for in-plane motion and the classical flexural plate equation for out-of-plane motion. The flange is modeled using two sets of Donnell shell equations: one for the left side of the flange and one for the right side of the flange. The governing differential equations are solved with unknown wave propagation coefficients multiplied by spatial domain and time domain functions which are inserted into equilibrium and continuity equations at the intersection of the web and flange and into boundary conditions at the edges of the system resulting in 24 algebraic equations. These equations are solved to yield the wave propagation coefficients and this produces a solution to the displacement field in all three dimensions. An example problem is formulated and compared to results from finite element analysis.

The stability of cassette walls in compression

NASA Astrophysics Data System (ADS)

Voutay, Pierre-Arnaud

Much research into the behaviour of cold formed steel columns in the last decade has focused on channel sections undergoing local, distortional and overall buckling. Light gauge steel cassette sections are a particular form of channel section which offers an alternative form of load-bearing wall assembly for use in low-rise steel framed construction. Cassette wall sections possess wide and slender flanges so that, by including intermediate stiffeners in these wide flanges, a significant increase in the ultimate load capacity may be achieved. However, the introduction of intermediate stiffeners also increases the number of buckling modes (stiffener buckling) and, therefore complicates the behaviour and increases the risk of interactive buckling between these modes. The work undertaken in this thesis aims to clarify the behaviour of wide flanges in compression with and without intermediate stiffeners. In this research, the distortional mode of web and narrow flange buckling was inhibited by connecting the narrow flanges of the cassettes together at suitable intervals. "Generalised Beam Theory" (GBT), which allows the individual buckling modes to be considered individually and in predetermined combinations, provides a particularly good tool with which to analyse and understand the buckling behaviour of cassette sections with and without intermediate stiffeners. "Generalised Beam Theory" (GBT) is used throughout this work to determine the elastic buckling stress of the sections studied (simply supported stiffened plates, as well as cassette sections). Since the economic design of cold-formed steel sections requires the consideration of post- buckling behaviour, elastic buckling values are not directly comparable with design code values which are usually based on the concept of effective width. Therefore, finite element analysis with both material and geometric nonlinearity has also been carried out in order to obtain the ultimate strength in the critical mode or mode combination. Firstly the results of experimental test are analysed and their behaviour reproduced numerically. This serves to explain the test results and verify the numerical model. Confidence in modelling non-linear instability phenomena with the finite element method is acquired. Secondly, an initial parametric study was undertaken on the behaviour of cassette sections with and without intermediate stiffeners. This study considers the effect of the length and overall buckling on the behaviour of cassette sections, the effect of load eccentricity and the effect of the rotational restraint given by the web to the stiffened wide flange. A second parametric study including 96 specimens was undertaken next. This study considered the effect of the number (up to three intermediate stiffeners) and sizes of intermediate stiffeners on slender flanges with a slenderness ratio between 150 ≤ w/t ≤ 600. A wide range of geometries was studied covering single and interactive buckling modes. Comparison of the ultimate strength obtained from finite element analysis with the ultimate strength obtained using the effective width approach of modem design codes such as Eurocode 3 part 1.3 (1996) and NAS (North American specification (2001)) was then possible. By integrating the stress distribution over the length of the specimen, the stiffened wide flange can be isolated from the rest of the section (webs and narrow flanges). Design procedures tor plate elements incorporating one or two intermediate stiffeners under compressive load are given in Eurocode 3; Part 1.3. However, cassette sections, which have wider and more slender flanges than typical sheeting and decking, are increasingly being used in practical construction. For such cases, the design procedures in Eurocode 3 are less well founded. An improvement of the Eurocode 3 procedure dealing with intermediate stiffeners is proposed and validated for one, two or three stiffeners. Throughout the work, simple expressions suitable for design calculations are presented. Modern design codes as well as Direct Strength Method are evaluated in the light of findings of this work and wherever possible suggestions for improvements are made.

Nuclear reactor fuel assembly duct-tube-to-inlet-nozzle attachment system

DOEpatents

Christiansen, David W.; Smith, Bob G.

1982-01-01

A reusable system for removably attaching the lower end 21 of a nuclear reactor fuel assembly duct tube to an upper end 11 of a nuclear reactor fuel assembly inlet nozzle. The duct tube's lower end 21 has sides terminating in locking tabs 22 which end in inwardly-extending flanges 23. The flanges 23 engage recesses 13 in the top section 12 of the inlet nozzle's upper end 11. A retaining collar 30 slides over the inlet nozzle's upper end 11 to restrain the flanges 23 in the recesses 13. A locking nut 40 has an inside threaded portion 41 which engages an outside threaded portion 15 of the inlet nozzle's upper end 11 to secure the retaining collar 30 against protrusions 24 on the duct tube's sides.

Ultrasonic flaw detection in a monorail box beam

NASA Astrophysics Data System (ADS)

Zheng, Peng; Greve, David W.; Oppenheim, Irving J.

2009-03-01

A steel box beam in a monorail application is constructed with an epoxy grout wearing surface, precluding visual inspection of its top flange. This paper describes a sequence of experimental research tasks to develop an ultrasonic system to detect flaws (such as fatigue cracks) in that flange, and the results of a field test to demonstrate system performance. The problem is constrained by the fact that the flange is exposed only along its longitudinal edges, and by the fact that permanent installation of transducers at close spacing was deemed to be impractical. The system chosen for development, after experimental comparison of alternate technologies, features angle-beam ultrasonic transducers with fluid coupling to the flange edge; the emitting transducers create transverse waves that travel diagonally across the width of the flange, where an array of receiving transducers detect flaw reflections and flaw shadows. The system rolls along the box beam, surveying (screening) the top flange for the presence of flaws. In a first research task, conducted on a full-size beam specimen, we compared waves generated from different transducer locations, either the flange edge or the web face, and at different frequency ranges. At relatively low frequencies, such as 100 kHz, we observed Lamb wave modes, and at higher frequency, in the MHz range, we observed nearlylongitudinal waves with trailing pulses. In all cases we observed little attenuation by the wearing surface and little influence of reflection at the web-flange joints. At the conclusion of this task we made the design decision to use edgemounted transducers at relatively high frequency, with correspondingly short wavelength, for best scattering from flaws. In a second research task we conducted experiments at 55% scale on a steel plate, with machined flaws of different size, and detected flaws of target size for the intended application. We then compared the performance of bonded transducers, fluid-coupled transducers, and angle-beam (wedge) transducers; from that comparison we made the design decision to use wedges, which beam the wave to increase the scattering from flaws. We also compared the performance of wired transducers using fluid coupling to that of wireless (inductively coupled) transducers mounted permanently. Although the wireless transducers achieved flaw detection, the necessary spacing (determined experimentally) would have required an impractical number of transducers. Therefore, we made the design decision to use wedge transducers with fluid coupling. In a third research task we developed and tested a rolling system with a water channel for acoustic coupling, including a study of its sensitivity to misalignment, and in a fourth task we devised a data display to create a pattern of reflections or shadows that could be easily interpreted as evidence of a flaw. Finally, we conducted a field test on the full-size system in a region containing bolt holes, which act as a physical simulation of a flaw, and show successful detection of reflections and shadows from those holes.

Preparing Technical Requirements for Third Party Contracting of Army Facilities

DTIC Science & Technology

1993-06-01

Boiler and Pressure Vessel Code Sec 9 Welding and Brazing Qualifications B 16.1 Cast Iron Pipe Flanges and Flanged...Control Terminology for Heating, Ventilating, Air Conditioning American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code B40.1...American National Standards Institute (ANSI) Boiler and Pressure Vessel Code (ASME) 125 Boilers and Pressure Vessels Code (ASTM) B31 Power

Experimental and numerical investigation of dual phase steels formability during laser-assisted hole-flanging

NASA Astrophysics Data System (ADS)

Motaman, S. A. H.; Komerla, K.; Storms, T.; Prahl, U.; Brecher, C.; Bleck, W.

2018-05-01

Today, in the automotive industry dual phase (DP) steels are extensively used in the production of various structural parts due to their superior mechanical properties. Hole-flanging of such steels due to simultaneous bending and stretching of sheet metal, is complex and associated with some issues such as strain and strain rate localization, development of micro-cracks, inhomogeneous sheet thinning, etc. In this study an attempt is made to improve the formability of DP sheets, by localized Laser heating. The Laser beam was oscillated in circular pattern rapidly around the pre-hole, blanked prior to the flanging process. In order to investigate formability of DP steel (DP1000), several uniaxial tensile tests were conducted from quasi to intermediate strain rates at different temperatures in warm regime. Additionally, experimentally acquired temperature and strain rate-dependent flow curves were fed into thermomechanical finite element (FE) simulation of the hole-flanging process using the commercial FE software ABAQUS/Explicit. Several FE simulations were performed in order to evaluate the effect of blank's initial temperature and punch speed on deformation localization, stress evolution and temperature distribution in DP1000 sheets during warm hole-flanging process. The experimental and numerical analyses revealed that prescribing a distribution of initial temperature between 300 to 400 °C to the blank and setting a punch speed that accommodates strain rate range of 1 to 5 s-1 in the blank, provides the highest strain hardening capacity in the considered rate and temperature regimes for DP1000. This is in fact largely due to the dynamic strain aging (DSA) effect which occurs due to pinning of mobile dislocations by interstitial solute atoms, particularly at elevated temperatures.

Duct attachment and extension for an air conditioning unit

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

Lang, R.D.; Frenia, F.J.

1986-12-16

An apparatus is described for attaching a fixed duct extension to the discharge opening of an air conditioning unit, the unit slidably inserted in and removed from a fixed through-the-wall sleeve, for supplying conditioned air to the space containing the unit and an adjacent space comprising: a discharge plenum assembly adapted to be connected to the unit encase the discharge opening. The discharge plenum assembly defines an air flow path for the conditioned air discharged from the unit and includes a first housing member having a forward wall, a rear wall, and a pair of opposed side walls joining themore » front wall to the rear wall, and a second housing member having a top wall connected to a front wall. The top wall and the front wall are fixedly attached to the rear wall and the forward wall respectively of the first housing member and forming a duct outlet in one of the side walls. The top wall and the front wall of the second housing member and one of the pair of opposed side walls of the lower housing member having longitudinal flanges extending therefrom forming a C-like flange; a bracket removably secured to the through the wall sleeve having an outwardly extending flange member at the top of the bracket; and a duct extension means secured to the outwardly extending flange of the bracket near one end and to the wall of the adjacent space at the opposite end. The duct extension means has a collar at one end configured to engage with the C-like flange whereby the unit with the discharge plenum assembly attached thereto slidably engages with and disengages from the through-the-wall sleeve while the duct extension is secured to the bracket.« less

Ceramic blade attachment system

DOEpatents

Shaffer, J.E.

1995-07-11

A turbine blade having a preestablished rate of thermal expansion is attached to a turbine disc having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade and forms a turbine assembly. The turbine blade has a root portion defining a pair of sides having a pair of grooves therein. The turbine assembly includes a pair of flanges between which the turbine blades are positioned. Each of the pair of flanges has a plurality of grooves defined therein. The grooves within the pair of flanges are aligned with the grooves in the blades and have a space formed therebetween. A plurality of spherical balls are positioned within the space. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade. 4 figs.

Ceramic blade attachment system

DOEpatents

Shaffer, James E.

1995-01-01

A turbine blade having a preestablished rate of thermal expansion is attached to a turbine disc having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade and forms a turbine assembly. The turbine blade has a root portion defining a pair of sides having a pair of grooves therein. The turbine assembly includes a pair of flanges between which the turbine blades are positioned. Each of the pair of flanges has a plurality of grooves defined therein. The grooves within the pair of flanges are aligned with the grooves in the blades and have a space formed therebetween. A plurality of spherical balls are positioned within the space. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade.

Joining and reinforcing a composite bumper beam and a composite crush can for a vehicle

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

Berger, Elisabeth; Decker, Leland; Armstrong, Dale

A front bumper beam and crush can (FBCC) system is provided for a vehicle. A bumper beam has an interior surface with a plurality of ribs extending therefrom. The ribs and the interior surface are made of a chopped fiber composite and cooperate to engage a crush can. The chopped fiber composite reinforces the engaging surfaces of the crush can and the interior surface of the bumper beam. The crush can has a tubular body made of a continuous fiber composite. The crush can has outwardly-extending flanges at an end spaced away from the bumper beam. The flanges are atmore » least partially provided with a layer of chopped fiber composite to reinforce a joint between the outwardly-extending flange and the vehicle frame.« less

Watching harmonics beat

NASA Astrophysics Data System (ADS)

Keeports, David

2015-04-01

Suppose you record a song on magnetic tape and duplicate your recording. You then simultaneously play back both tapes. To the rim of one of the tape reels, also known as the reel's flange, you keep applying gentle pressure and then releasing that pressure so that your reel alternates between slightly lagging the other and then catching up with it. The resulting small pitch differences between the two tapes give rise to an intriguing and pleasant sound often described as swirling or jet-like. A Wikipedia article1 lists dozens of popular songs that incorporate this "flanging" effect. Well represented are songs by the Beatles and Jimi Hendrix as well as by artists from recent decades. But perhaps the most important is an obscure 1945 recording by guitarist and musical inventor Les Paul, who is recognized as the discoverer of flanging.

Shrink-Fit Solderable Inserts Seal Hermetically

NASA Technical Reports Server (NTRS)

Croucher, William C.

1992-01-01

Shrink-fit stainless-steel insert in aluminum equipment housing allows electrical connectors to be replaced by soldering, without degrading hermeticity of housing or connector. Welding could destroy electrostatic-sensitive components and harm housing and internal cables. Steel insert avoids problems because connector soldered directly to it rather than welded to housing. Seals between flange and housing, and between connector and flange resistant to leaks, even after mechanical overloading and thermal shocking.

Photovoltaic concentrator assembly with optically active cover

DOEpatents

Plesniak, Adam P

2014-01-21

A photovoltaic concentrator assembly that includes a housing that defines an internal volume and includes a rim, wherein the rim defines an opening into the internal volume, a photovoltaic cell positioned in the internal volume, and an optical element that includes an optically active body and a flange extending outward from the body, wherein the flange is sealingly engaged with the rim of the housing to enclose the internal volume.

Energy efficient skylight construction

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

Jentoft, A.P.; Couture, P.A.

1978-02-14

An energy efficient skylight construction is described. A skylight cover is secured by a frame to a curbing comprised of an insulating core, the interior and exterior surfaces of which are covered by non-combustible shields separated along the upper and lower surfaces of the curbing by a gap which serves as a ''thermal break'' between the highly conductive inner and outer shields. The frame is pierced by drain openings the exterior of which are covered by a filter type material such as foam or glass fibers that is both absorbtive of moisture and resistant to the passage of air. Themore » frame is secured to the outward portion of the curbing and includes a flange extending inward across the gap between the shields, which serves as a gutter to collect condensation which drips off the glazing. The inward portion of the flange is covered with an insulating gasket which prevents condensation from forming on the flange and which prevents the warmer, more moisture laden, inside air from reaching the cold underside of the gutter flange or the edge of the outerskin. The core insulation is inserted, without adhesives, into the assembled inside skin, and then the exposed surface of the insulation is bonded to the inside surface of the outer skin.« less

Three Dimensional Imaging of Helicon Wave Fields Via Magnetic Induction Probes

DTIC Science & Technology

2009-07-13

Elastomer Flange 50 The chamber is pumped by a Varian TV-300 HT turbomolecular vacuum pump with a pumping speed of 250 l/s backed by a dry scroll ... vacuum diffusion chamber with pump locations .................................................. 49 Figure 3.2. RF power delivery system...steel, 0.5 meter diameter by 1.0 meter long vacuum chamber. It has 24 access ports / flanges of varying diameter for diagnostic feed-throughs, pumping

Coining seal

DOEpatents

Mancebo, Lloyd

1976-01-01

A bakeable high pressure-vacuum seal is provided in which an inductile sealing element having a butterfly shaped crosssection with protruding sharp edges at each of the four corners, is sandwiched between two ductile sealing elements, the sandwiched assembly then being compressed between the surfaces of the flange elements of a high pressure or high vacuum vessel to coin the ductile sealing element into the surface of the inductile sealing element as well as the surfaces of the flange elements.

Orbital Winch

NASA Technical Reports Server (NTRS)

Hoyt, Robert (Inventor); Slostad, Jeffrey T. (Inventor); Frank, Scott (Inventor); Barnes, Ian M. (Inventor)

2016-01-01

Orbital winch having: lower and upper frames; spool having upper and lower flanges with lower flange attached to lower frame; axial tether guide mounted to upper frame; secondary slewing ring coaxial with spool and rotatably mounted to upper frame, wherein secondary slewing ring's outer surface has gearing; upper tether guide mounted to inner surface of secondary slewing ring; linear translation means having upper end mounted to upper frame and lower end mounted on lower frame; primary slewing ring rotatably mounted within linear translation means allowing translation axially between flanges, wherein primary slewing ring's outer surface has gearing; lower tether guide mounted on primary slewing ring's inner surface; pinion rod having upper end mounted to upper frame and lower end mounted to lower frame, wherein pinion rod's teeth engage primary and secondary slewing rings' outer surface teeth; and tether passing through axial, upper, and lower tether guides and winding around spool.

Development of a 2-stage shear-cutting-process to reduce cut-edge-sensitivity of steels

NASA Astrophysics Data System (ADS)

Gläsner, T.; Sunderkötter, C.; Hoffmann, H.; Volk, W.; Golle, R.

2017-09-01

The edge cracking sensitivity of AHSS and UHSS is a challenging factor in the cold forming process. Expanding cut holes during flanging operations is rather common in automotive components. During these flanging operations the pierced hole is stretched so that its diameter is increased. These flanging operations stretch material that has already been subjected to large amounts of plastic deformation, therefore forming problems may occur. An innovative cutting process decreases micro cracks in the cutting surface and facilitates the subsequent cold forming process. That cutting process consists of two stages, which produces close dimensional tolerance and smooth edges. As a result the hole expanding ratio was increased by nearly 100 % when using thick high strength steels for suspension components. The paper describes the mechanisms of the trimming process at the cut edge, and the positive effect of the 2-stage shear-cutting process on the hole extension capability of multiphase steels.

Design, Fabrication and Test of Composite Curved Frames for Helicopter Fuselage Structure

NASA Technical Reports Server (NTRS)

Lowry, D. W.; Krebs, N. E.; Dobyns, A. L.

1984-01-01

Aspects of curved beam effects and their importance in designing composite frame structures are discussed. The curved beam effect induces radial flange loadings which in turn causes flange curling. This curling increases the axial flange stresses and induces transverse bending. These effects are more important in composite structures due to their general inability to redistribute stresses by general yielding, such as in metal structures. A detailed finite element analysis was conducted and used in the design of composite curved frame specimens. Five specimens were statically tested and compared with predicted and test strains. The curved frame effects must be accurately accounted for to avoid premature fracture; finite element methods can accurately predict most of the stresses and no elastic relief from curved beam effects occurred in the composite frames tested. Finite element studies are presented for comparative curved beam effects on composite and metal frames.

Self-locking double retention redundant pull pin release

NASA Technical Reports Server (NTRS)

Killgrove, Thomas O. (Inventor)

1987-01-01

A double-retention redundant pull pin release system is disclosed. The system responds to a single pull during an intentional release operation. A spiral-threaded main pin is seated in a mating bore in a housing, which main pin has a flange fastened thereon at the part of the main pin which is exterior to the housing. Accidental release tends to rotate the main pin. A secondary pin passes through a slightly oversized opening in the flange and is seated in a second bore in the housing. The pins counteract against one another to prevent accidental release. A frictional lock is shared between the main and secondary pins to enhance further locking of the system. The secondary pin, in response to a first pull, is fully retracted from its bore and flange hole. Thereafter the pull causes the main pin to rotate free of the housing to release, for example, a parachute mechanism.

Improving Strength of Postbuckled Panels Through Stitching

NASA Technical Reports Server (NTRS)

Jegley, Dawn C.

2007-01-01

The behavior of blade-stiffened graphite-epoxy panels with impact damage is examined to determine the effect of adding through-the-thickness stitches in the stiffener flange-to-skin interface. The influence of stitches is evaluated by examining buckling and failure for panels with failure loads up to 3.5 times greater than buckling loads. Analytical and experimental results from four configurations of panel specimens are presented. For each configuration, two panels were manufactured with skin and flanges held together with through-the-thickness stitches introduced prior to resin infusion and curing and one panel was manufactured with no stitches holding the flange to the skin. No mechanical fasteners were used for the assembly of any of these panels. Panels with and without low-speed impact damage were loaded to failure in compression. Buckling and failure modes are discussed. Stitching had little effect on buckling loads but increased the failure loads of impact-damaged panels by up to 30%.

One-Piece Battery Incorporating A Circulating Fluid Type Heat Exchanger

DOEpatents

Verhoog, Roelof

2001-10-02

A one-piece battery comprises a tank divided into cells each receiving an electrode assembly, closure means for the tank and a circulating fluid type heat exchanger facing the relatively larger faces of the electrode assembly. The fluid flows in a compartment defined by two flanges which incorporate a fluid inlet orifice communicating with a common inlet manifold and a fluid outlet orifice communicating with a common outlet manifold. The tank comprises at least two units and each unit comprises at least one cell delimited by walls. The wall facing a relatively larger face of the electrode assembly constitutes one of the flanges. Each unit further incorporates a portion of an inlet and outlet manifold. The units are fastened together so that the flanges when placed face-to-face form a sealed circulation compartment and the portions of the same manifold are aligned with each other.

Inertial energy storage device

DOEpatents

Knight, Jr., Charles E.; Kelly, James J.; Pollard, Roy E.

1978-01-01

The inertial energy storage device of the present invention comprises a composite ring formed of circumferentially wound resin-impregnated filament material, a flanged hollow metal hub concentrically disposed in the ring, and a plurality of discrete filament bandsets coupling the hub to the ring. Each bandset is formed of a pair of parallel bands affixed to the hub in a spaced apart relationship with the axis of rotation of the hub being disposed between the bands and with each band being in the configuration of a hoop extending about the ring along a chordal plane thereof. The bandsets are disposed in an angular relationship with one another so as to encircle the ring at spaced-apart circumferential locations while being disposed in an overlapping relationship on the flanges of the hub. The energy storage device of the present invention has the capability of substantial energy storage due to the relationship of the filament bands to the ring and the flanged hub.

Web flexibility and I-beam torsional oscillation

NASA Astrophysics Data System (ADS)

Stephen, N. G.; Wang, P. J.

1986-08-01

Two recent theories on torsional oscillation of general doubly-symmetric non-circular cross-section beams incorporate a second order effect, that of in-plane shear deformation involving a change in cross-sectional shape, and are found to give excellent agreement with exact results for an elliptical section rod. For "technical" torsional oscillation theories of I-section beams this in-plane shear has previously been considered within the flanges only; in the present work the greater effect of shear distortion of the web is included, having previously been considered only in static analysis. The theory predicts three modes of wave propagation, one of which is essentially torsional in character; a second mode may be identified with predominatly flange bending according to the second branch of Timoshenko beam theory whilst a new mode involves individual flange torsion with asymmetric web deformation, and has the lowest phase velocity except at the longest wavelength. An alternative symmetric web deformation is also considered.

Mechanics of Re-Torquing in Bolted Flange Connections

NASA Technical Reports Server (NTRS)

Gordon, Ali P.; Drilling Brian; Weichman, Kyle; Kammerer, Catherine; Baldwin, Frank

2010-01-01

It has been widely accepted that the phenomenon of time-dependent loosening of flange connections is a strong consequence of the viscous nature of the compression seal material. Characterizing the coupled interaction between gasket creep and elastic bolt stiffness has been useful in predicting conditions that facilitate leakage. Prior advances on this sub-class of bolted joints has lead to the development of (1) constitutive models for elastomerics, (2) initial tightening strategies, (3) etc. The effect of re-torque, which is a major consideration for typical bolted flange seals used on the Space Shuttle fleet, has not been fully characterized, however. The current study presents a systematic approach to characterizing bolted joint behavior as the consequence of sequentially applied torques. Based on exprimenta1 and numerical results, the optimal re-torquing parameters have been identified that allow for the negligible load loss after pre-load application

Flexure fatigue testing of 90 deg graphite/epoxy composites

NASA Technical Reports Server (NTRS)

Peck, Ann Nancy W.

1995-01-01

A great deal of research has been performed characterizing the in-plane fiber-dominated properties, under both static and fatigue loading, of advanced composite materials. To the author's knowledge, no study has been performed to date investigating fatigue characteristics in the transverse direction. This information is important in the design of bonded composite airframe structure where repeated, cyclic out-of-plane bending may occur. Recent tests characterizing skin/stringer debond failures in reinforced composite panels where the dominant loading in the skin is flexure along the edge of the frame indicate failure initiated either in the skin or else the flange, near the flange tip. When failure initiated in the skin, transverse matrix cracks formed in the surface skin ply closest to the flange and either initiated delaminations or created matrix cracks in the next lower ply, which in turn initiated delaminations. When failure initiated in the flanges, transverse cracks formed in the flange angle ply closest to the skin and initiated delamination. In no configuration did failure propagate through the adhesive bond layer. For the examined skin/flange configurations, the maximum transverse tension stress at failure correlates very well with the transverse tension strength of the composites. Transverse tension strength (static) data of graphite epoxy composites have been shown to vary with the volume of material stressed. As the volume of material stressed increased, the strength decreased. A volumetric scaling law based on Weibull statistics can be used to predict the transverse strength measurements. The volume dependence reflects the presence of inherent flaws in the microstructure of the lamina. A similar approach may be taken to determine a volume scale effect on the transverse tension fatigue behavior of graphite/epoxy composites. The objective of this work is to generate transverse tension strength and fatigue S-N characteristics for composite materials using 3-point flexure tests of 90 deg graphite/epoxy specimens. Investigations will include the volume scale effect as well as frequency and span-to-thickness ratio effects. Prior to the start of the experimental study, an analytical study using finite element modeling will be performed to investigate the span-to-thickness effect. The ratio of transverse flexure stress to shear stress will be monitored and its values predicted by the FEM analysis compared with the value obtained using a 'strength of materials' based approach.

75 FR 74610 - Airworthiness Directives; Airbus Model A300 B2-1C, B2K-3C, B2-203, B4-2C, B4-103, and B4-203...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-01

...] attachment fitting lower flanges, DGAC [Direction G[eacute]n[eacute]rale de l'Aviation Civile] France AD 2003... [right-hand] and LH [left-hand] attachment fitting lower flanges, DGAC [Direction G[eacute]n[eacute]rale...-57A6101. This AD is revised to introduce an optional terminating action which consists of spot-facing the...

Composite Pressure Vessel Including Crack Arresting Barrier

NASA Technical Reports Server (NTRS)

DeLay, Thomas K. (Inventor)

2013-01-01

A pressure vessel includes a ported fitting having an annular flange formed on an end thereof and a tank that envelopes the annular flange. A crack arresting barrier is bonded to and forming a lining of the tank within the outer surface thereof. The crack arresting barrier includes a cured resin having a post-curing ductility rating of at least approximately 60% through the cured resin, and further includes randomly-oriented fibers positioned in and throughout the cured resin.

Leak detection aid

DOEpatents

Steeper, Timothy J.

1989-01-01

A leak detection apparatus and method for detecting leaks across an O-ring sealing a flanged surface to a mating surface is an improvement in a flanged surface comprising a shallow groove following O-ring in communication with an entrance and exit port intersecting the shallow groove for injecting and withdrawing, respectively, a leak detection fluid, such as helium. A small quantity of helium injected into the entrance port will flow to the shallow groove, past the O-ring and to the exit port.

Evaluation of Fatigue Strength Improvement by CFRP Laminates and Shot Peening onto the Tension Flanges Joining Corrugated Steel Webs

PubMed Central

Wang, Zhi-Yu; Wang, Qing-Yuan; Liu, Yong-Jie

2015-01-01

Corrugated steel web with inherent high out-of-plane stiffness has a promising application in configuring large span highway bridge girders. Due to the irregularity of the configuration details, the local stress concentration poses a major fatigue problem for the welded flange plates of high strength low alloy structural steels. In this work, the methods of applying CFRP laminate and shot peening onto the surfaces of the tension flanges were employed with the purpose of improving the fatigue strength of such configuration details. The effectiveness of this method in the improvement of fatigue strength has been examined experimentally. Test results show that the shot peening significantly increases hardness and roughness in contrast to these without treatment. Also, it has beneficial effects on the fatigue strength enhancement when compared against the test data of the joints with CFRP strengthening. The stiffness degradation during the loading progress is compared with each treatment. Incorporating the stress acting on the constituent parts of the CFRP laminates, a discussion is made regarding the mechanism of the retrofit and related influencing factors such as corrosion and economic cost. This work could enhance the understanding of the CFRP and shot peening in repairing such welded details and shed light on the reinforcement design of welded joints between corrugated steel webs and flange plates. PMID:28793509

Assessment of the LC-2 Prelaunch Fatigue Spectra of the CM-to-SM Flange Weld

NASA Technical Reports Server (NTRS)

Dawicke, David S.; Newman, John A.

2008-01-01

The pad stay and rollout components of the Ares I-X life cycle can generate cyclic stress oscillations to the vehicle that could initiate and grow fatigue cracks from weld defects. The Ares I-X Project requested that a study be performed to determine if stabilization of the vehicle is required to reduce the stresses that could initiate and grow fatigue cracks at the flange-to-skin weld of the Command Module (CM) and Service Module (SM) interface. A fatigue crack growth analysis was conducted that used loads (LC-2) and stress analyses developed by the Ares I-X Project and utilized material data and analysis methods developed by a critical initial flaw size (CIFS) analysis conducted by NASA Engineering and Safety Center (NESC) for the Upper Stage Simulator (USS) of the Ares I-X vehicle. A full CIFS analysis for the CM-to-SM flange-to-skin weld was not performed because the full flight spectrum was not provided and was not necessary to answer the question posed by the Ares I-X Project. Instead, an approach was developed to determine if the crack growth due to the pad stay and rollout components of the flight spectrum would adversely influence the CIFS. The approach taken used a number of conservative assumptions that eliminated the need for high-fidelity analyses and additional material testing, but still provided a bounding solution for the uncertainties of the problem. The results from this analysis indicate that the LC-2 pad stay and rollout spectrum components would not produce significant fatigue crack growth on the CM-to-SM flange-to-skin weld. Thus, from a fatigue crack growth standpoint, no stabilization is required to reduce the LC-2 pad stay and rollout cyclic stresses on the CM-to-SM flange-to-skin weld.

Plastic mechanism of multi-pass double-roller clamping spinning for arc-shaped surface flange

NASA Astrophysics Data System (ADS)

Fan, Shuqin; Zhao, Shengdun; Zhang, Qi; Li, Yongyi

2013-11-01

Compared with the conventional single-roller spinning process, the double-roller clamping spinning(DRCS) process can effectively prevent the sheet metal surface wrinkling and improve the the production efficiency and the shape precision of final spun part. Based on ABAQUS/Explicit nonlinear finite element software, the finite element model of the multi-pass DRCS for the sheet metal is established, and the material model, the contact definition, the mesh generation, the loading trajectory and other key technical problems are solved. The simulations on the multi-pass DRCS of the ordinary Q235A steel cylindrical part with the arc-shaped surface flange are carried out. The effects of number of spinning passes on the production efficiency, the spinning moment, the shape error of the workpiece, and the wall thickness distribution of the final part are obtained. It is indicated definitely that with the increase of the number of spinning passes the geometrical precision of the spun part increases while the production efficiency reduces. Moreover, the variations of the spinning forces and the distributions of the stresses, strains, wall thickness during the multi-pass DRCS process are revealed. It is indicated that during the DRCS process the radical force is the largest, and the whole deformation area shows the tangential tensile strain and the radial compressive strain, while the thickness strain changes along the generatrix directions from the compressive strain on the outer edge of the flange to the tensile strain on the inner edge of the flange. Based on the G-CNC6135 NC lathe, the three-axis linkage computer-controlled experimental device for DRCS which is driven by the AC servo motor is developed. And then using the experimental device, the Q235A cylindrical parts with the arc-shape surface flange are formed by the DRCS. The simulation results of spun parts have good consistency with the experimental results, which verifies the feasibility of DRCS process and the reliability of the finite element model for DRCS.

Testing and Analysis of Composite Skin/Stringer Debonding Under Multi-Axial Loading

NASA Technical Reports Server (NTRS)

Krueger, Ronald; Cvitkovich, Michael K.; O'Brien, T. Kevin; Minguet, Pierre J.

2000-01-01

A consistent step-wise approach is presented to investigate the damage mechanism in composite bonded skin/stringer constructions under uniaxial and biaxial (in-plane/out-of-plane) loading conditions. The approach uses experiments to detect the failure mechanism, computational stress analysis to determine the location of first matrix cracking and computational fracture mechanics to investigate the potential for delamination growth. In a first step, tests were performed on specimens, which consisted of a tapered composite flange, representing a stringer or frame, bonded onto a composite skin. Tests were performed under monotonic loading conditions in tension, three-point bending, and combined tension/bending to evaluate the debonding mechanisms between the skin and the bonded stringer. For combined tension/bending testing, a unique servohydraulic load frame was used that was capable of applying both in-plane tension and out-of-plane bending loads simultaneously. Specimen edges were examined on the microscope to document the damage occurrence and to identify typical damage patterns. For all three load cases, observed failure initiated in the flange, near the flange tip, causing the flange to almost fully debond from skin. In a second step, a two dimensional plane-strain finite element model was developed to analyze the different test cases using a geometrically nonlinear solution. For all three loading conditions, computed principal stresses exceeded the transverse strength of the material in those areas of the flange where the matrix cracks had developed during the tests. In a third step, delaminations of various lengths were simulated in two locations where delaminations were observed during the tests. The analyses showed that at the loads corresponding to matrix ply crack initiation computed strain energy release rates exceeded the values obtained from a mixed mode failure criterion in one location, Hence. Unstable delamination propagation is likely to occur as observed in the experiments.

Testing and Analysis of Composite Skin/Stringer Debonding under Multi-Axial Loading

NASA Technical Reports Server (NTRS)

Krueger, Ronald; Cvitkovich, Michael; OBrien, Kevin; Minguet, Pierre J.

2000-01-01

A consistent step-wise approach is presented to investigate the damage mechanism in composite bonded skin/stringer constructions under uniaxial and biaxial (in-plane/out-of-plane) loading conditions. The approach uses experiments to detect the failure mechanism, computational stress analysis to determine the location of first matrix cracking and computational fracture mechanics to investigate the potential for delamination growth. In a first step, tests were performed on specimens, which consisted of a tapered composite flange, representing a stringer or frame, bonded onto a composite skin. Tests were performed under monotonic loading conditions in tension, three-point bending, and combined tension/bending to evaluate the debonding mechanisms between the skin and the bonded stringer. For combined tension/bending testing, a unique servohydraulic load frame was used that was capable of applying both in-plane tension and out-of-plane bending loads simultaneously. Specimen edges were examined on the microscope to document the damage occurrence and to identify typical damage patterns. For all three load cases, observed failure initiated in the flange, near the flange tip, causing the flange to almost fully debond from the skin. In a second step, a two-dimensional plane-strain finite element model was developed to analyze the different test cases using a geometrically nonlinear solution. For all three loading conditions, computed principal stresses exceeded the transverse strength of the material in those areas of the flange where the matrix cracks had developed during the tests. In a third step, delaminations of various lengths were simulated in two locations where delaminations were observed during the tests. The analyses showed that at the loads corresponding to matrix ply crack initiation computed strain energy release rates exceeded the values obtained from a mixed mode failure criterion in one location. Hence, unstable delamination propagation is likely to occur as observed in the experiments.

Gaskets of teflon-bonded EPDM halt leakage from acid lines - low sealing force design eliminates flange distress

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

Walker, I.S.; Gaines, A.

1987-11-01

The W.R. Grace Chemical Division plant in Lake Charles, LA had to stop producing catalysts for the oil refining industry whenever a piping system for 98% sulfuric acid developed a leak. Gaskets of a nonasbestos material were being used between the flanges of the steel pipe lined with TFE or polypropylene. The flange bolts were kept tight, but the gaskets usually failed to maintain a leaktight seal with the acid at 60 psi for more than a few weeks or months. The acid lines had to be drained before the faulty gasket could be replaced, and production downtime would rangemore » from one to three hours. In July 1986, the plant decided to try a chemical resistant gasket of Teflon molded and bonded to a core of Shore A 65-66 durometer EPDM rubber in the acid lines. The resilient gasket also has patented double convex rings on both faces for optimum sealing with only one-eighth the bolt tightening torque commonly required with flat-faced gaskets. The low sealing force requirement prolongs the life of the gasket, eliminates plastic cold flow at the flange of lined steel pipe, and avoids stresses that can damage thermoplastic and fiberglass piping systems. The gasket has a temperature range of {minus}4 to 210{degree}F and is available in 1/2 through 12 inch sizes that conform to ANSI B16.1 flange dimensions. Alternative gasket materials are Kynar PVDF-bonded EPDM and EPDM without a fluoropolymer laminate. The Teflon-bonded EPDM gaskets eliminated unscheduled catalyst production downtime due to leakage from the sulfuric acid piping system. The plant maintains an inventory of the low torque gasket, but has never had to replace any that have been in service since July 1986.« less

Dynamic Uniaxial Tensile Loading of Vector Polymers

DTIC Science & Technology

2011-11-01

to apply the loading velocity to the strip at x = 0 after impact by a steel slug projectile. The flange has two sets of grooves. One set, denoted as...travels down the barrel . The strip is clamped to the outside of the barrel at x = L. A Photron SA1 high-speed video camera with a framing rate of...nominal stress. Equation 1 is expressed in terms of particle displacement to obtain the wave equation Flange Gun Barrel Rubber Strip Clamp x = 0

Leak detection aid

DOEpatents

Steeper, T.J.

1989-12-26

A leak detection apparatus and method for detecting leaks across an O-ring sealing a flanged surface to a mating surface is an improvement in a flanged surface comprising a shallow groove following O-ring in communication with an entrance and exit port intersecting the shallow groove for injecting and withdrawing, respectively, a leak detection fluid, such as helium. A small quantity of helium injected into the entrance port will flow to the shallow groove, past the O-ring and to the exit port. 2 figs.

Millimeter Waves Techniques Conference (1974) Held on 26-28 March 1974. Volume 2

DTIC Science & Technology

1974-03-01

GHz Coaxial Connector by M. A. Maury, Jr. and W. A. Wambach Maury Microwave Corp. Cucamonga, Cal. 91730 INTRODUCTION A new minature coax connector has...however, accurate joining depends upon such factors as the alignment of bolt holes , paint on the back of the flange that can affect the seating of the...of the locations of pins and holes to a close tolerance is crucial, 3) for low loss requirements a differently designed flange with a rectangular boss

Regenerative Engine Analysis Program (REAP).

DTIC Science & Technology

1981-01-01

Output Shaft Forged SAE 9310 Performance for the TSE Model 1071 is shown in Figures 41, 42, and 43 for static and flight conditions at three altitudes...Flange - Air Inlet 3 in. dia 2 0.72 Duct - Air Outlet, 3.25 in. OD 0.050 2 0.78 Flange - Air Outlet 3.25 in. dia 2 0.78 Weld and Miscellaneous -- 2.67... 4140 tubes, plus the outer case. (This assumes straight line trajectory with no tumbling.) This would result in leakage of nearly one percent of the

Stepping Stone Mechanism: Carrier-Free Long-Range Magnetism Mediated by Magnetized Cation States in Quintuple Layer

NASA Astrophysics Data System (ADS)

Chan, Chunkai; Zhang, Xiaodong; Zhang, Yiou; Tse, Kinfai; Deng, Bei; Zhang, Jingzhao; Zhu, Junyi

2018-01-01

The long-range magnetism observed in group-V tellurides quintuple layers is the only working example of carrier-free dilute magnetic semiconductors (DMS), whereas the physical mechanism is unclear, except the speculation on the band topology enhanced van Vleck paramagnetism. Based on DFT calculations, we find a stable long-range ferromagnetic order in a single quintuple layer of Cr-doped Bi2Te3 or Sb2Te3, with the dopant separation more than 9 Å. This configuration is the global energy minimum among all configurations. Different from the conventional super exchange theory, the magnetism is facilitated by the lone pair derived anti-bonding states near the cations. Such anti-bonding states work as stepping stones merged in the electron sea and conduct magnetism. Further, spin orbit coupling induced band inversion is found to be insignificant in the magnetism. Therefore, our findings directly dismiss the common misbelief that band topology is the only factor that enhances the magnetism. We further demonstrate that removal of the lone pair derived states destroys the long-range magnetism. This novel mechanism sheds light on the fundamental understanding of long-range magnetism and may lead to discoveries of new classes of DMS. Supported by Chinese University of Hong Kong (CUHK) under Grant No 4053084, University Grants Committee of Hong Kong under Grant No 24300814, and the Start-up Funding of CUHK.

Cryogenics Testbed Laboratory Flange Baseline Configuration

NASA Technical Reports Server (NTRS)

Acuna, Marie Lei Ysabel D.

2013-01-01

As an intern at Kennedy Space Center (KSC), I was involved in research for the Fluids and Propulsion Division of the NASA Engineering (NE) Directorate. I was immersed in the Integrated Ground Operations Demonstration Units (IGODU) project for the majority of my time at KSC, primarily with the Ground Operations Demonstration Unit Liquid Oxygen (GODU L02) branch of IGODU. This project was established to develop advancements in cryogenic systems as a part of KSC's Advanced Exploration Systems (AES) program. The vision of AES is to develop new approaches for human exploration, and operations in and beyond low Earth orbit. Advanced cryogenic systems are crucial to minimize the consumable losses of cryogenic propellants, develop higher performance launch vehicles, and decrease operations cost for future launch programs. During my internship, I conducted a flange torque tracking study that established a baseline configuration for the flanges in the Simulated Propellant Loading System (SPLS) at the KSC Cryogenics Test Laboratory (CTL) - the testing environment for GODU L02.

Analytical and numerical investigation of bolted steel ring flange connection for offshore wind monopile foundations

NASA Astrophysics Data System (ADS)

Madsen, C. A.; Kragh-Poulsen, J.-C.; Thage, K. J.; Andreassen, M. J.

2017-12-01

The monopile foundation is the dominant solution for support of wind turbines in offshore wind farms. It is normally grouted to the transition piece which connects the foundation to the turbine. Currently, the bolted steel ring flange connection is investigated as an alternative. The monopile--transition piece connection has specific problems, such as out-of-verticality and installation damage from driving the MP into the seabed and it is not fully known how to design for these. This paper presents the status of the ongoing development work and an estimate of what still needs to be covered in order to use the connection in practice. This involves presentation of an analytical and non-linear FE analysis procedure for the monopile-transition piece connection composed of two L flanges connected with preloaded bolts. The connection is verified for ultimate and fatigue limit states based on an integrated load simulation carried out by the turbine manufacturer.

Molten carbonate fuel cell separator

DOEpatents

Nickols, Richard C.

1986-09-02

In a stacked array of molten carbonate fuel cells, a fuel cell separator is positioned between adjacent fuel cells to provide isolation as well as a conductive path therebetween. The center portion of the fuel cell separator includes a generally rectangular, flat, electrical conductor. Around the periphery of the flat portion of the separator are positioned a plurality of elongated resilient flanges which form a gas-tight seal around the edges of the fuel cell. With one elongated flange resiliently engaging a respective edge of the center portion of the separator, the sealing flanges, which are preferably comprised of a noncorrosive material such as an alloy of yttrium, iron, aluminum or chromium, form a tight-fitting wet seal for confining the corrosive elements of the fuel cell therein. This arrangement permits a good conductive material which may be highly subject to corrosion and dissolution to be used in combination with a corrosion-resistant material in the fuel cell separator of a molten carbonate fuel cell for improved fuel cell conductivity and a gas-tight wet seal.

Molten carbonate fuel cell separator

DOEpatents

Nickols, R.C.

1984-10-17

In a stacked array of molten carbonate fuel cells, a fuel cell separator is positioned between adjacent fuel cells to provide isolation as well as a conductive path therebetween. The center portion of the fuel cell separator includes a generally rectangular, flat, electrical conductor. Around the periphery of the flat portion of the separator are positioned a plurality of elongated resilient flanges which form a gas-tight seal around the edges of the fuel cell. With one elongated flange resiliently engaging a respective edge of the center portion of the separator, the sealing flanges, which are preferably comprised of a noncorrosive material such as an alloy of yttrium, iron, aluminum or chromium, form a tight-fitting wet seal for confining the corrosive elements of the fuel cell therein. This arrangement permits a good conductive material which may be highly subject to corrosion and dissolution to be used in combination with a corrosion-resistant material in the fuel cell separator of a molten carbonate fuel cell for improved fuel cell conductivity and a gas-tight wet seal.

Risk assessment of flange climb derailment of a rail vehicle

NASA Astrophysics Data System (ADS)

Vlakhova, A. V.

2015-01-01

We study the wheel flange climb onto the railhead, which is one of the most dangerous regimes of motion and can lead to derailment. The tangential components of the wheel-rail interaction forces are described by the creep model with small slips taken into account. We pass to the limit of infinite rigidity of the interacting bodies (zero slip velocities). It is shown that, in the actual service conditions of rail vehicle motion, neglecting the wheel-rail slip is not justified; namely, the limit model is determined by the primary Dirac constraints, i.e., finite relations between coordinates and momenta arising owing to the system Lagrangian degeneration. The obtained nonclassical model allows one to study the efficiency of some railway motion safety criteria and analytically estimate derailment conditions, which depend on the flange shape, the track curvature radius, the height of the vehicle center of mass, the wheel-rail interaction forces, the coefficients of friction of the interacting surfaces, and the external perturbation forces and moments.

High sensitive nonlinear modulation magnetoelectric magnetic sensors with a magnetostrictive metglas structure based on bell-shaped geometry

NASA Astrophysics Data System (ADS)

Ma, Jiashuai; Jiao, Jie; Fang, Cong; Zhao, Xiangyong; Luo, Haosu

2016-05-01

In this paper both linear and nonlinear magnetoelectric (ME) effects have been investigated intensively. In order to obtain magnetic amplification, we fabricated 3 multi-push-pull mode magnetoelectric laminated composites metglas/PMNT/metglas based on dumbbell-shaped metglas. The linear magnetoelectric charge coefficient is enhanced to 2600 pC/Oe at 2 Hz based on dumbbell-shaped metglas and it increases as the end-flange width of the dumbbell-shaped metglas increases at 2 Hz, respectively. Based on these 3 ME composites, we establish an active mode nonlinear modulation system for ME magnetic sensor, the sensitivity of which are enhanced to 80, 100 and 102 pT / √ Hz at 1 Hz for the composites with the end-flange width 20, 15 and 10 mm, respectively, via nonlinear ME　modulation method. Strain distribution simulations illustrate the theoretically accurate amplification of the dumbbell-shaped geometry. The center strains of 3 dumbbell-shaped metglas decrease as the width of end-flanges decreases

Using a Glacial Isostatic Adjustment model to investigate the contribution of the Antarctic and Greenland Ice sheet to the Last Interglacial Sea Level.

NASA Astrophysics Data System (ADS)

Bradley, Sarah; Hindmarsh, Richard C. A.

2014-05-01

Eustatic Sea Level during the Last interglacial (LIG) is likely to have been 4- 6 m higher than present day, with the observed relative sea level (RSL) at numerous far-field sites even higher [Dutton and Lambeck, 2012]. It has been suggested to generate this higher than present day sea level requires a retreat of both the Antarctic (AIS) and Greenland (GIS) Ice sheets beyond the present day extent, but the exact contribution of these two global ice sheets has yet to be resolved. By combing a Glacial Isostatic Adjustment (GIA) model with a suite of LIG ice-loading histories we will address a number of outstanding issues (i) What was the contribution of the AIS and GIS to ESL, (ii) Was the AIS or the GIS smaller during the LIG than the present interglacial? (iii) Can we generate the observed higher LIG RSL at a range of far-field sites? The suite of AIS and GIS ice-loading histories is constrained using the most recent near-field evidence, LIG stable isotope ice core data [Dahl-Jensen et al., 2013; Masson-Delmotte et al., 2011] and the output from ice sheet and climate models [Helsen et al., 2013; Pollard and DeConto, 2009; Stone et al., 2013]. Comparing the predicted RSL to a recent database of observed LIG far-field sea level [Dutton and Lambeck, 2012] allows for an assessment of the plausibility of the suite of ice loading histories. With this study, we aim to provide insight into the LIG history of the AIS and GIS. Dahl-Jensen, D., et al. (2013), Eemian interglacial reconstructed from a Greenland folded ice core, Nature, 493(7433), 489-494. Dutton, A., and K. Lambeck (2012), Ice Volume and Sea Level During the Last Interglacial, Science, 337(6091), 216-219. Helsen, M. M., W. J. van de Berg, R. S. W. van de Wal, M. R. van den Broeke, and J. Oerlemans (2013), Coupled regional climate-ice-sheet simulation shows limited Greenland ice loss during the Eemian, Clim Past, 9(4), 1773-1788. Masson-Delmotte, V., et al. (2011), A comparison of the present and last interglacial periods in six Antarctic ice cores, Clim Past, 7(2), 397-423. Pollard, D., and R. M. DeConto (2009), Modelling West Antarctic ice sheet growth and collapse through the past five million years, Nature, 458(7236), 329-U389. Stone, E. J., D. J. Lunt, J. D. Annan, and J. C. Hargreaves (2013), Quantification of the Greenland ice sheet contribution to Last Interglacial sea level rise, Clim Past, 9(2), 621-639.

Theoretical reconsideration of antiferromagnetic Fermi surfaces in URu2Su2

NASA Astrophysics Data System (ADS)

Yamagami, Hiroshi

2011-01-01

In an itinerant 5f-band model, the antiferromagnetic (AFM) Fermi surfaces of URu2Si2 are reconsidered using a relativistic LAPW method within a local spin-density approximation, especially taking into account the lattice parameters dependent on pressures. The reduction of the z-coordinate of the Si sites results in the effect of flattening the Ru-Si layers of URu2Si2 crystal structure, thus weakening a hybridization/mixing between the U-5f and Ru-4d states in the band structure. Consequently the 5f bands around the Fermi level are more flat in the dispersion with decreasing the z-coordinate, thus producing three closed Fermi surfaces like "curing-stone", "rugby-ball " and "ball". The origins of de Haas-van Alphen branches can be qualitatively interpreted from the obtained AFM Fermi surfaces.

Numerical simulation of the hole-flanging process for steel-polymer sandwich sheets

NASA Astrophysics Data System (ADS)

Griesel, Dominic; Keller, Marco C.; Groche, Peter

2018-05-01

In light of increasing demand for lightweight structures, hybrid materials are frequently used in load-optimized parts. Sandwich structures like metal-polymer sandwich sheets provide equal bending stiffness as their monolithic counterparts at a drastically reduced weight. In addition, sandwich sheets have noise-damping properties, thus they are well-suited for a large variety of parts, e.g. façade and car body panels, but also load-carrying components. However, due to the creep tendency and low heat resistance of the polymer cores, conventional joining technologies are only applicable to a limited degree. Through hole-flanging it is possible to create branches in sandwich sheets to be used as reinforced joints. While it is state of the art for monolithic materials, hole-flanging of sandwich sheets has not been investigated yet. In order to simulate this process for different material combinations and tool geometries, an axisymmetric model has been developed in the FE software Abaqus/CAE. In the present paper, various modeling strategies for steel-polymer sandwich sheets are examined, including volume elements, shell elements and combinations thereof. Different methods for joining the distinct layers in the FE model are discussed. By comparison with CT scans and optical 3D measurements of experimentally produced hole-flanges, the feasibility of the presented models is evaluated. Although a good agreement of the numerical and experimental results has been achieved, it becomes clear that the classical forming limit diagram (FLD) does not adequately predict failure of the steel skins.

3-D Analysis of Flanged Joints Through Various Preload Methods Using ANSYS

NASA Astrophysics Data System (ADS)

Murugan, Jeyaraj Paul; Kurian, Thomas; Jayaprakash, Janardhan; Sreedharapanickar, Somanath

2015-10-01

Flanged joints are being employed in aerospace solid rocket motor hardware for the integration of various systems or subsystems. Hence, the design of flanged joints is very important in ensuring the integrity of motor while functioning. As these joints are subjected to higher loads due to internal pressure acting inside the motor chamber, an appropriate preload is required to be applied in this joint before subjecting it to the external load. Preload, also known as clamp load, is applied on the fastener and helps to hold the mating flanges together. Generally preload is simulated as a thermal load and the exact preload is obtained through number of iterations. Infact, more iterations are required when considering the material nonlinearity of the bolt. This way of simulation will take more computational time for generating the required preload. Now a days most commercial software packages use pretension elements for simulating the preload. This element does not require iterations for inducing the preload and it can be solved with single iteration. This approach takes less computational time and thus one can study the characteristics of the joint easily by varying the preload. When the structure contains more number of joints with different sizes of fasteners, pretension elements can be used compared to thermal load approach for simulating each size of fastener. This paper covers the details of analyses carried out simulating the preload through various options viz., preload through thermal, initial state command and pretension element etc. using ANSYS finite element package.

Experiment to Capture Gaseous Products from Shock-Decomposed Materials

NASA Astrophysics Data System (ADS)

Holt, William; Mock, Willis, Jr.

2001-06-01

Recent gas gun experiments have been performed in which initially porous polytetrafluoroethylene (PTFE) powder specimens were shock compressed inside a closed steel container and soft recovered^1,2. Although a powder decomposition residue was produced in the container and analyzed in situ, no attempt was made to recover any gaseous decomposition products for analysis. The purpose of the present experiment is to extend these earlier studies to include the capture of gaseous products. The specimen container is constructed from two metal flanges and a metal gasket, held together by high-strength bolts. A cavity between the flanges contains a porous powder specimen of material to be shock-decomposed, and is connected to a gas sample cylinder via a metal tube and a valve. The system is evacuated prior to the experiment. A gas-gun-accelerated metal disk impacts the flat surface of one of the flanges. On impact, a stress wave passes through the flange and into the specimen material. If gaseous products are formed, they can be collected in the sample cylinder for subsequent analyses by mass spectrometry. Results will be presented for PTFE powder specimens. Work supported by the NSWCDD Independent Research Office. ^1W. Mock, Jr., W. H. Holt, and G. I. Kerley, in Shock Compression of Condensed Matter - 1997, S. C. Schmidt, D. P. Dandekar, and J. W. Forbes (AIP, New York, 1998), p. 671. ^2W. H. Holt, W. Mock, Jr., and F. Santiago, J. Appl. Phys. 88, 5485 (2000).

Heating equipment installation system

DOEpatents

Meuschke, Robert E.; Pomaibo, Paul P.

1991-01-01

A method for installing a heater unit assembly (52, 54) in a reactor pressure vessel (2) for performance of an annealing treatment on the vessel (2), the vessel (2) having a vertical axis, being open at the top, being provided at the top with a flange (6) having a horizontal surface, and being provided internally, at a location below the flange (6), with orientation elements (8) which are asymmetrical with respect to the vertical axis, by the steps of: providing an orientation fixture (10) having an upwardly extending guide member (18) and orientation elements (14, 16) and installing the orientation fixture (10) in the vessel (2) so that the orientation elements (14,16) of the orientation fixture (10) mate with the orientation elements (8) of the pressure vessel (2) in order to establish a defined position of the orientation fixture (10) in the pressure vessel (2), and so that the guide member (18) projects above the pressure vessel (2) flange (6); placing a seal ring (30) in a defined position on the pressure vessel (2) flange (6) with the aid of the guide member (18); mounting at least one vertical, upwardly extending guide stud (40) upon the seal ring (30); withdrawing the orientation fixture (10) from the pressure vessel (2); and moving the heater unit assembly (52,54) vertically downwardly into the pressure vessel (2) while guiding the heater unit assembly (52,54) along a path with the aid of the guide stud (40).

OPERATION SUNBEAM, SHOT SMALL BOY. Project Officer’s Report - Project 2.2, Measurement of Fast-Neutron Dose Rate as a Function of Time

DTIC Science & Technology

1985-09-01

Calibration 44 3.1.3 The SPIDER Calibration 45 3.1.*» Thermistor Temperature Detector Calibration. . 45 3.2 Amplifier Calibration 45 3.2.1...of a material with high conductivity and preferably high permeability. For the bunker construction, welded one-inch soft-steel plates were chosen for...Kovar flanges (metal- to-ceramic seal). The external plates are hel1arc- welded to the flanges. The external plate facing away from the incoming

Tracking Damage Nucleation and Propagation in Metallic Materials Using a Planar Biaxial Test System

DTIC Science & Technology

2008-09-30

along the horizontal (x) axis. The dimensions of the system are shown in Fig. 1. It was delivered by MTS to ASU on Sep. 12, 2008, approximately 1 year...the y (vertical) and x ( horizontal ) axes is 3 Py/Px = 1.0. Figure 5 shows contours of resultant displacement in the gage area of both the simple and...sensors were used. Oile strain gauge is 1nounte<l on the horizontal flange (Fig. 4a), and one on the vertical flange (Fig. 4a) and two strain gauges

JACKETED FISSIONABLE MEMBER

DOEpatents

Boller, E.R.; Robinson, J.W.

1960-09-13

A fuel element design for a nuclear reactor is presented. The fuel element comprises a cylindrical fuel body having a portion of smaller diameter at each end thereof with an annular flange at the extreme ends of these portions of smaller diameter. An end cap fits over the ends of the fuel body and has an internal annular groove adapted to receive the flange. The fuel body and end caps are disposed in a cup-shaped jacket, a closure disc completing the enclosure of the fuel body, and tht caps are bonded over their entire periphery to the jacket.

Stress Analysis of Beams with Shear Deformation of the Flanges

NASA Technical Reports Server (NTRS)

Kuhn, Paul

1937-01-01

This report discusses the fundamental action of shear deformation of the flanges on the basis of simplifying assumptions. The theory is developed to the point of giving analytical solutions for simple cases of beams and of skin-stringer panels under axial load. Strain-gage tests on a tension panel and on a beam corresponding to these simple cases are described and the results are compared with analytical results. For wing beams, an approximate method of applying the theory is given. As an alternative, the construction of a mechanical analyzer is advocated.

Quick-Connect/Disconnect Joint For Truss Structures

NASA Technical Reports Server (NTRS)

Sprague, Benny B.

1991-01-01

Simple connector used for temporary structures and pipes. Truss connector joins and aligns structural members. Consists of two sections, one flanged and other with mating internal groove. When flanged half inserted in groove, moves lever of trigger mechanism upward. Cone then shoots into grooved half. Attached without tools in less than 2 seconds and taken apart just as quickly and easily. Developed for assembling structures in outer space, also useful for temporary terrestrial structures like scaffolds and portable bleachers. With modifications, used to join sections of pipelines carrying liquids or gases.

Design and Delivery of HMT Half-Shaft Prototype

DTIC Science & Technology

2012-11-01

spindle welded to the outer joint output is ease of Design  and Delivery of HMT Half‐ Shaft  Prototype    24    assembly. Flange 1 contains threaded... spindle , and splined shafts . Also, the spindle of the production design is splined to match the splines of the hub internals. 2.2. Analysis The...inner-joint (Figure 33). Design  and Delivery of HMT Half‐ Shaft  Prototype    27      Figure 33: FBD of Flange/ Spindle Applying Newton’s Laws to the

Variable volume combustor with aerodynamic fuel flanges for nozzle mounting

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

McConnaughhay, Johnie Franklin; Keener, Christopher Paul; Johnson, Thomas Edward

2016-09-20

The present application provides a combustor for use with a gas turbine engine. The combustor may include a number of micro-mixer fuel nozzles and a fuel injection system for providing a flow of fuel to the micro-mixer fuel nozzles. The fuel injection system may include a number of support struts supporting the fuel nozzles and for providing the flow of fuel therethrough. The fuel injection system also may include a number of aerodynamic fuel flanges connecting the micro-mixer fuel nozzles and the support struts.

In vitro evaluation of five core materials.

PubMed

Gu, Steven; Rasimick, Brian J; Deutsch, Allan S; Musikant, Barry L

2007-01-01

This in vitro study determined the fracture strength of five core materials supported by two different endodontic dowels. Diametral tensile strength and microhardness of the three resin composite core materials used in this study were also tested. The fracture strength study used one lanthanide-reinforced flowable resin composite (Ti-Core Auto E), one titanium- and lanthanide-reinforced composite (Ti-Core), one lanthanide-reinforced composite (Ti-Core Natural), and two metal-reinforced glass ionomer core materials (Ketac Silver and GC Miracle Mix). Two types of dowels were used: a multitiered, split-shank threaded dowel with a flange (#1 Flexi-Flange) and one without a flange design (#1 Flexi-Post). The specimens were divided into ten groups. Each tooth/dowel and core specimen was placed in a special jig at 45 degrees and subjected to a load by a universal testing machine. The diametral tensile strength and the microhardness of the three resin composite core materials were measured by a universal testing machine and Barcol hardness tester, respectively. All test groups contained ten specimens. The fracture strength value of the resin composite core materials was significantly larger ( p < 0.0001) than those for the metal-reinforced glass-ionomer core materials. Analysis of variance (ANOVA) also showed that the Flexi-Flange dowel interacted with Ti-Core and Ti-Core Auto E to significantly ( p < 0.0013) increase the fracture strength relative to the Flexi-Post. One-way ANOVA revealed that there were no significant differences between them in terms of diametral tensile strength. The Barcol hardness values of the composite core materials were statistically different ( p < 0.0001), with the Ti-Core the highest, followed by Ti-Core Natural, then Ti-Core Auto E. Resin composite core material performed better than glass ionomer material in this in vitro study. The flowable composite core material performed about the same in terms of fracture strength and diametral tensile strength compared with nonflowable composites. Combined with certain core materials, the flange design increased the fracture strength of the tooth/dowel and core combination.

Development of Mathematic Model of Cold Welding at Drawing-up the Flange Joint of Pneumohydraulic Systems

NASA Astrophysics Data System (ADS)

Boyko, Y. S.

2002-01-01

Provision of high airtightness of joints of pipe- lines of pneumohydraulic systems (PHS) operating under high pressure, is an important task for designing and operation of launch vehicles. In the process of assembly and tests of PHS of launch vehicles, it was found that detachable flange joints do not lose their airtightness after removal of fastening elements, even in conditions of standard loads. The task of this work is in studying a phenomenon connected with initiation of the observed effect of adhesion and also stresses in the zone of contact at drawing- up the flange detachable joints with a plastic gasket. Investigations have shown that density of the joint is kept due to cold welding, as the created conditions are helpful for that process. As a result of the investigations performed, we have developed a mathematic model which is based on application of the theory of metal bonds; that theory explains the essence of the effect observed. Basic factors which provide optimum mode of cold welding, are effort which can cause microplastic deformation and form maximum contact, and also quality of processing the material of the surfaces joined. Strength of all- metal joint depends on factual area of contact. So, surface processing quality defines a configuration of microbulges which come into contact not simultaneously, and their stressed state is different, and it influences the character of dependence of the contact area on loading. Results of calculations by the mathematic model are expressed by dependencies of factual area of contact and a single diameter of the contact spot on the load applied which compresses the materials with various physical properties, and on the surface processing quality. The mathematic model allows to explain the common character of the cold welding process in detachable flange joints with the plastic gasket, to determine the nature and the character of acting forces, to define kinetics and the mechanism of formation of cold welding of detachable joints. It also helps to analyze the state of airtightness and to metal welding technology in the plastic state at drawing- up of detachable flange joints with a plastic gasket and to review cold welding as a positive phenomenon.

Inspection of defects of composite materials in inner cylindrical surfaces using endoscopic shearography

NASA Astrophysics Data System (ADS)

Macedo, Fabiano Jorge; Benedet, Mauro Eduardo; Fantin, Analucia Vieira; Willemann, Daniel Pedro; da Silva, Fábio Aparecido Alves; Albertazzi, Armando

2018-05-01

This work presents the development of a special shearography system with radial sensitivity and explores its applicability for detecting adhesion flaws on internal surfaces of flanged joints of composite material pipes. The inspection is performed from the inner surface of the tube where the flange is adhered. The system uses two conical mirrors to achieve radial sensitivity. A primary 45° conical mirror is responsible for promoting the inspection of the internal tubular surface on its 360° A special Michelson interferometer is formed replacing one of the plane mirrors by a conical mirror. The image reflected by this conical mirror is shifted away from the image center in a radial way and a radial shear is produced on the images. The concept was developed and a prototype built and tested. First, two tubular steel specimens internally coated with composite material and having known artificial defects were analyzed to test the ability of the system to detect the flaws. After the principle validation, two flanged joints were then analyzed: (a) a reference one, without any artificial defects and (b) a test one with known artificial defects, simulating adhesion failures with different dimensions and locations. In all cases, thermal loading was applied through a hot air blower on the outer surface of the joint. The system presented very good results on all inspected specimens, being able to detect adhesion flaws present in the flanged joints. The experimental results obtained in this work are promising and open a new front for inspections of inner surfaces of pipes with shearography.

Time-of-flight mass spectrometry of mineral volatilization: Toward direct composition analysis of shocked mineral vapor

NASA Astrophysics Data System (ADS)

Austin, Daniel E.; Shen, Andy H. T.; Beauchamp, J. L.; Ahrens, Thomas J.

2012-04-01

We have developed an orthogonal-acceleration time-of-flight mass spectrometer to study the volatiles produced when a mineral's shock-compressed state is isentropically released, as occurs when a shock wave, driven into the mineral by an impact, reflects upon reaching a free surface. The instrument is designed to use a gun or explosive-launched projectile as the source of the shock wave, impact onto a flange separating a poor vacuum and the high vacuum (10-7 Torr) interior of the mass spectrometer, and transmission of the shock wave through the flange to a mineral sample mounted on the high-vacuum side of the flange. The device extracts and analyzes the neutrals and ions produced from the shocked mineral prior to the possible occurrence of collateral instrument damage from the shock-inducing impact. The instrument has been tested using laser ablation of various mineral surfaces, and the resulting spectra are presented. Mass spectra are compared with theoretical distributions of molecular species, and with expected distributions from laser desorption.

Development of a new seal for use on large openings of pressurized spacecraft

NASA Technical Reports Server (NTRS)

Weddendorf, B.

1994-01-01

The goal of this project was to design, build, and test an example of the seal invented by the author for use on Space Station Freedom and patented in 1991. The seal features a metallic spring core and replaceable elastomeric sealing elements. The metallic spring is designed to retain the sealing force of the elastomeric element against both sides of face seal gland for any specified amount of waviness or separation of the glands. A seal able to tolerate at least 1.3 mm (0.05 in) of flange distortion or separation and a test fixture of this seal which allowed direct comparison testing of O-rings were built. These designs were tested to compare leakage at different amounts of flange deflection. Results of the testing show the development seal exceeded its requirement to seal 1.3 mm of flange separation by 1 mm. This compared with the O-ring leakage, increasing dramatically at 0.5 mm of separation. The development seal also leaked at a lower rate than the O-ring seals in all tests.

Seating arrangement and structure of a spool within a well casing

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

Lien, N.C.; Olsen, D.G.

1990-07-10

This patent describes a well construction having a vertical well casing and a spool. It comprises: the spool being insertable into the well casing and the spool having a flange with a skirt that bottoms against a collar in the well casing to form a seated contact engagement between the skirt and the collar, a support web connected to the flange and extending substantially perpendicular to the skirt. The support web has an undersurface which extends upwardly and radially inwardly from the flange,a sleeve section connected to the web radially inwardly thereof from which a pipe section is suspended therefrom,more » and a ring portion at a junction of the support web and the sleeve about which transmitted forces are resolved, the skirt and the collar being angled at an angle {theta} relative to the vertical such that {theta} has a value less than tan {theta} equal to 1/{mu} and greater than tan {theta} equal to {mu} where {mu} equals the coefficient of static friction between the skirt and the collar.« less

Summary of reported agriculture and irrigation water use in northwestern Arkansas counties, 1991

USGS Publications Warehouse

Holland, T.W.; Manning, C.A.; Stafford, K.L.

1993-01-01

This report summarizes the 1991 water-use reporting through the Conservation District Offices in the following northwestern Arkansas counties: Baxter, Benton, Boone, Carroll, Cleburne, Fulton, Izard, Madison, Marion, Newton, Searcy, Sharp, Stone, Van Buren, and Washington. The number of withdrawal registrations for northwestern Arkansas counties was 106 (16 groundwater and 90 surface water). Water withdrawals reported during the registration process total 41.72 Mgal/d (0.74 Mgal/d groundwater and 40.98 Mgal/d surface water) for agriculture and 3.33 Mgal/d (0.27 Mgal/d groundwater and 3.06 Mgal/d surface water) for irrigation. The registration reports for 1991 indicate that this water was applied to 3,588 acres of land to irrigate rice, soybeans, cash grains, hay, oats, vegetables, sod, berries, fruit trees, and timber as well as for the agricultural use of animal aquaculture.

Nuclear reactor reflector

DOEpatents

Hopkins, Ronald J.; Land, John T.; Misvel, Michael C.

1994-01-01

A nuclear reactor reflector is disclosed that comprises a stack of reflector blocks with vertical water flow passages to cool the reflector. The interface between blocks is opposite support points for reactor fuel rods. Water flows between the reflector and the reactor barrel from passages in a bottom block. The top block contains a flange to limit this flow and the flange has a slot to receive an alignment pin that is welded to the barrel. The pin is held in the slot by two removable shims. Alignment bars extend the length of the stack in slots machined in each block when the stack is assembled.

Nuclear reactor reflector

DOEpatents

Hopkins, R.J.; Land, J.T.; Misvel, M.C.

1994-06-07

A nuclear reactor reflector is disclosed that comprises a stack of reflector blocks with vertical water flow passages to cool the reflector. The interface between blocks is opposite support points for reactor fuel rods. Water flows between the reflector and the reactor barrel from passages in a bottom block. The top block contains a flange to limit this flow and the flange has a slot to receive an alignment pin that is welded to the barrel. The pin is held in the slot by two removable shims. Alignment bars extend the length of the stack in slots machined in each block when the stack is assembled. 12 figs.

Pulse-Echo Phased Array Ultrasonic Inspection of Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS)

NASA Technical Reports Server (NTRS)

Johnston, Pat H.

2010-01-01

A PRSEUS test article was subjected to controlled impact on the skin face followed by static and cyclic axial compressions. Phased array ultrasonic inspection was conducted before impact, and after each of the test conditions. A linear phased array probe with a manual X-Y scanner was used for interrogation. Ultrasound showed a delamination between the skin and stringer flange adjacent to the impact. As designed, the stitching in the flange arrested the lateral flaw formation. Subsequent ultrasonic data showed no delamination growth due to continued loading. Keywords: Phased Array, Ultrasonics, Composites, Out-of-Autoclave

Heat shield manifold system for a midframe case of a gas turbine engine

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

Mayer, Clinton A.; Eng, Jesse; Schopf, Cheryl A.

A heat shield manifold system for an inner casing between a compressor and turbine assembly is disclosed. The heat shield manifold system protects the outer case from high temperature compressor discharge air, thereby enabling the outer case extending between a compressor and a turbine assembly to be formed from less expensive materials than otherwise would be required. In addition, the heat shield manifold system may be configured such that compressor bleed air is passed from the compressor into the heat shield manifold system without passing through a conventional flange to flange joint that is susceptible to leakage.

Pilot cryo tunnel: Attachments, seals, and insulation

NASA Technical Reports Server (NTRS)

Wilson, J. F.; Ware, G. D.; Ramsey, J. W., Jr.

1974-01-01

Several different tests are described which simulated the actual configuration of a cryogenic wind tunnel operating at pressures up to 5 atmospheres (507 kPa) and temperatures from -320 F (78K) to 120 F (322K) in order to determine compatible bolting, adequate sealing, and effective insulating materials. The evaluation of flange attachments (continuous threaded studs) considered bolting based on compatible flanges, attachment materials, and prescribed bolt elongations. Various types of seals and seal configurations were studied to determine suitability and reusability under the imposed pressure and temperature loadings. The temperature profile was established for several materials used for structural supports.

A novel speech prosthesis for mandibular guidance therapy in hemimandibulectomy patient: A clinical report

PubMed Central

Adaki, Raghavendra; Shigli, Kamal; Hormuzdi, Dinshaw M.; Gali, Sivaranjani

2016-01-01

Treating diverse maxillofacial patients poses a challenge to the maxillofacial prosthodontist. Rehabilitation of hemimandibulectomy patients must aim at restoring mastication and other functions such as intelligible speech, swallowing, and esthetics. Prosthetic methods such as palatal ramp and mandibular guiding flange reposition the deviated mandible. Such prosthesis can also be used to restore speech in case of patients with debilitating speech following surgical resection. This clinical report gives detail of a hemimandibulectomy patient provided with an interim removable dental speech prosthesis with composite resin flange for mandibular guidance therapy. PMID:27041917

Variation in developmental arrest among male orangutans: a comparison between a Sumatran and a Bornean population

PubMed Central

2013-01-01

Introduction The presence of two sexually active male morphs with different reproductive tactics in a single species is rare among mammals. The most striking case of bimaturism among primates is exhibited by the orangutan (Pongo spp), in which one adult morph, the unflanged male, irreversibly develops into another one, the flanged form, but may remain arrested in the unflanged state for many years. However, it has been suggested that such arrest is less common among Bornean orangutans (Pongo pygmaeus) compared to Sumatrans (Pongo abelii). To investigate this possible inter-specific difference we compared both the number of developing males and the ratios of the two male morphs at two long-term study sites, Suaq Balimbing on Sumatra and Tuanan on Borneo. Results First, we observed a significantly greater number of flanged than unflanged males per month in the Tuanan study area, whereas the opposite pattern held at Suaq. Second, the same contrast held for the total number of identified individuals over the study, with more flanged than unflanged males at Tuanan and the opposite at Suaq. These differences were mainly due to transient males. For Tuanan, the identification results were confirmed by detailed genetic analyses. Finally, we recorded a higher proportion of unflanged males that became flanged during any given year at Tuanan than at Suaq. Conclusion These results show that developmental arrest is far more common at Suaq than at Tuanan. Preliminary comparisons suggest that this is a general contrast between the island taxa of orangutans and should help efforts to identify the function and proximate control of developmental arrest in orangutan males. PMID:23510027

Apparatus and methods for impingement cooling of an undercut region adjacent a side wall of a turbine nozzle segment

DOEpatents

Burdgick, Steven Sebastian; Itzel, Gary Michael

2001-01-01

A gas turbine nozzle segment has outer and inner bands. Each band includes a side wall, a cover and an impingement plate between the cover and nozzle wall defining two cavities on opposite sides of the impingement plate. Cooling steam is supplied to one cavity for flow through apertures of the impingement plate to cool the nozzle wall. The side wall of the band and inturned flange define with the nozzle wall an undercut region. The inturned flange has a plurality of apertures for directing cooling steam to cool the side wall between adjacent nozzle segments.

Caracterização do rotator de instrumentos do telescópio de 1,60m.

NASA Astrophysics Data System (ADS)

Rodrigues, F.; Nishida, K.; Faúndez-Abans, M.; Campos, R. P.

2004-04-01

Na base do tubo do telescópio de 1,60m do Observatório do Pico dos Dias (OPD) encontra-se o flange de rotação de instrumentos “Rotator”. Neste flange são fixados todos os instrumentos científicos tais como câmeras, espectrógrafos e fotômetros, utilizados nas missões observacionais. Nesta nota técnica são relatados a utilização e o ganho de tempo obtido na operação de posicionamento do rotator, após sua automatização.

Using Aerogel-Based Insulation Material To Prevent Foam Loss on the Liquid-Hydrogen Intertank

NASA Technical Reports Server (NTRS)

2008-01-01

Uninsulated areas on cryogenic propellant tanks and feedlines cause moisture in the air to condense or ice to form. Flange joints, bracket supports, expansion bellows, and other cavities are uninsulated by design. These areas cannot be sealed because conventional thermal insulation materials would restrict mechanical articulations. Aerogel-based thermal insulation systems are able to seal critical locations such as the liquid-oxygen (LO2) feedline bellows. A new thermal insulation system was also necessary between the intertank wall, flange, and the liquid-hydrogen (LH2) tank dome, where there is a cavity (or crevice) with an exposed 20-K surface. When nitrogen gas is used for purging within the intertank volume, it condenses on this cold surface. Some solid nitrogen may also form on the colder side of the crevice. Voids or discontinuities within the foam can pressurize and cause areas of foam to weaken and break off, reducing thermal efficiency and creating potentially dangerous debris. To prevent this foam loss, we developed a thermal insulation system using bulk-fill aerogel material and demonstrated it with a one-tenth-scale model of the LH2 intertank flange area

Characterization of Fatigue Damage for Bonded Composite Skin/Stringer Configurations

NASA Technical Reports Server (NTRS)

Paris, Isabelle; Cvitkovich, Michael; Krueger, Ronald

2008-01-01

The fatigue damage was characterized in specimens which consisted of a tapered composite flange bonded onto a composite skin. Quasi-static tension tests were performed first to determine the failure load. Subsequently, tension fatigue tests were performed at 40%, 50%, 60% and 70% of the failure load to evaluate the debonding mechanisms. For four specimens, the cycling loading was stopped at intervals. Photographs of the polished specimen edges were taken under a light microscope to document the damage. At two diagonally opposite corners of the flange, a delamination appeared to initiate at the flange tip from a matrix crack in the top 45deg skin ply and propagated at the top 45deg/-45deg skin ply interface. At the other two diagonally opposite corners, a delamination running in the bondline initiated from a matrix crack in the adhesive pocket. In addition, two specimens were cut longitudinally into several sections. Micrographs revealed a more complex pattern inside the specimen where the two delamination patterns observed at the edges are present simultaneously across most of the width of the specimen. The observations suggest that a more sophisticated nondestructive evaluation technique is required to capture the complex damage pattern of matrix cracking and multi-level delaminations.

The Systematic Classification of Gallbladder Stones

PubMed Central

Qiao, Tie; Ma, Rui-hong; Luo, Xiao-bing; Yang, Liu-qing; Luo, Zhen-liang; Zheng, Pei-ming

2013-01-01

Background To develop a method for systematic classification of gallbladder stones, analyze the clinical characteristics of each type of stone and provide a theoretical basis for the study of the formation mechanism of different types of gallbladder stones. Methodology A total of 807 consecutive patients with gallbladder stones were enrolled and their gallstones were studied. The material composition of gallbladder stones was analyzed using Fourier Transform Infrared spectroscopy and the distribution and microstructure of material components was observed with Scanning Electron Microscopy. The composition and distribution of elements were analyzed by an X-ray energy spectrometer. Gallbladder stones were classified accordingly, and then, gender, age, medical history and BMI of patients with each type of stone were analyzed. Principal Findings Gallbladder stones were classified into 8 types and more than ten subtypes, including cholesterol stones (297), pigment stones (217), calcium carbonate stones (139), phosphate stones (12), calcium stearate stones (9), protein stones (3), cystine stones (1) and mixed stones (129). Mixed stones were those stones with two or more than two kinds of material components and the content of each component was similar. A total of 11 subtypes of mixed stones were found in this study. Patients with cholesterol stones were mainly female between the ages of 30 and 50, with higher BMI and shorter medical history than patients with pigment stones (P<0.05), however, patients with pigment, calcium carbonate, phosphate stones were mainly male between the ages of 40 and 60. Conclusion The systematic classification of gallbladder stones indicates that different types of stones have different characteristics in terms of the microstructure, elemental composition and distribution, providing an important basis for the mechanistic study of gallbladder stones. PMID:24124459

Clonorcis sinensis eggs are associated with calcium carbonate gallbladder stones.

PubMed

Qiao, Tie; Ma, Rui-hong; Luo, Zhen-liang; Yang, Liu-qing; Luo, Xiao-bing; Zheng, Pei-ming

2014-10-01

Calcium carbonate gallbladder stones were easily neglected because they were previously reported as a rare stone type in adults. The aim of this study was to investigate the relationship between calcium carbonate stones and Clonorchis sinensis infection. A total of 598 gallbladder stones were studied. The stone types were identified by FTIR spectroscopy. The C. sinensis eggs and DNA were detected by microscopic examination and real-time fluorescent PCR respectively. And then, some egg-positive stones were randomly selected for further SEM examination. Corresponding clinical characteristics of patients with different types of stones were also statistically analyzed. The detection rate of C. sinensis eggs in calcium carbonate stone, pigment stone, mixed stone and cholesterol stone types, as well as other stone types was 60%, 44%, 36%, 6% and 30%, respectively, which was highest in calcium carbonate stone yet lowest in cholesterol stone. A total of 182 stones were egg-positive, 67 (37%) of which were calcium carbonate stones. The C. sinensis eggs were found adherent to calcium carbonate crystals by both light microscopy and scanning electron microscopy. Patients with calcium carbonate stones were mainly male between the ages of 30 and 60, the CO2 combining power of patients with calcium carbonate stones were higher than those with cholesterol stones. Calcium carbonate gallbladder stones are not rare, the formation of which may be associated with C. sinensis infection. Copyright © 2014 Elsevier B.V. All rights reserved.

Measuring stone volume - three-dimensional software reconstruction or an ellipsoid algebra formula?

PubMed

Finch, William; Johnston, Richard; Shaida, Nadeem; Winterbottom, Andrew; Wiseman, Oliver

2014-04-01

To determine the optimal method for assessing stone volume, and thus stone burden, by comparing the accuracy of scalene, oblate, and prolate ellipsoid volume equations with three-dimensional (3D)-reconstructed stone volume. Kidney stone volume may be helpful in predicting treatment outcome for renal stones. While the precise measurement of stone volume by 3D reconstruction can be accomplished using modern computer tomography (CT) scanning software, this technique is not available in all hospitals or with routine acute colic scanning protocols. Therefore, maximum diameters as measured by either X-ray or CT are used in the calculation of stone volume based on a scalene ellipsoid formula, as recommended by the European Association of Urology. In all, 100 stones with both X-ray and CT (1-2-mm slices) were reviewed. Complete and partial staghorn stones were excluded. Stone volume was calculated using software designed to measure tissue density of a certain range within a specified region of interest. Correlation coefficients among all measured outcomes were compared. Stone volumes were analysed to determine the average 'shape' of the stones. The maximum stone diameter on X-ray was 3-25 mm and on CT was 3-36 mm, with a reasonable correlation (r = 0.77). Smaller stones (<9 mm) trended towards prolate ellipsoids ('rugby-ball' shaped), stones of 9-15 mm towards oblate ellipsoids (disc shaped), and stones >15 mm towards scalene ellipsoids. There was no difference in stone shape by location within the kidney. As the average shape of renal stones changes with diameter, no single equation for estimating stone volume can be recommended. As the maximum diameter increases, calculated stone volume becomes less accurate, suggesting that larger stones have more asymmetric shapes. We recommend that research looking at stone clearance rates should use 3D-reconstructed stone volumes when available, followed by prolate, oblate, or scalene ellipsoid formulas depending on the maximum stone diameter. © 2013 The Authors. BJU International © 2013 BJU International.

Treatment of the Infected Stone.

PubMed

Marien, Tracy; Miller, Nicole L

2015-11-01

Infected kidney stones refer to stones that form because of urinary tract infections with urease-producing bacteria, secondarily infected stones of any composition, or stones obstructing the urinary tract leading to pyelonephritis. The mainstay of treatment of infection stones is complete stone removal. Kidney stones that obstruct the urinary tract and cause obstructive pyelonephritis are also frequently referred to as infected stones. Obstructive pyelonephritis is a urologic emergency as it can result in sepsis and even death. Infection stones and obstructive stones causing pyelonephritis are different disease processes, and their workup and management are described separately. Copyright © 2015 Elsevier Inc. All rights reserved.

Imaging-based assessment of the mineral composition of urinary stones: an in vitro study of the combination of hounsfield unit measurement in noncontrast helical computerized tomography and the twinkling artifact in color Doppler ultrasound.

PubMed

Hassani, Hakim; Raynal, Gauthier; Spie, Romain; Daudon, Michel; Vallée, Jean-Noël

2012-05-01

We evaluated the value of combining noncontrast helical computerized tomography (NCHCT) and color Doppler ultrasound in the assessment of the composition of urinary stones. In vitro, we studied 120 stones of known composition, that separate into the five main types: 18 calcium oxalate monohydrate (COM) stones, 41 calcium oxalate dihydrate (COD) stones, 24 uric acid stones, 25 calcium phosphate stones and 12 cystine calculi. Stones were characterized in terms of their Hounsfield density (HU) in NCHCT and the presence of a twinkling artifact (TA) in color Doppler ultrasound. There were statistically significant HU differences between calcium and non-calcium stones (p < 0.001), calcium oxalate stones and calcium phosphate stones (p < 0.001) and uric acid stones and cystine calculi (p < 0.001) but not between COM and COD stones (p = 0.786). Hence, the HU was a predictive factor of the composition of all types of stones, other than for COM and COD stones within the calcium oxalate class (p > 0.05). We found that the TA does not enable differentiation between calcium and non-calcium stones (p > 0.999), calcium oxalate stones and calcium phosphate stones (p = 0.15), or uric acid stones and cystine calculi (p = 0.079). However, it did reveal a significant difference between COM and COD stones (p = 0.002). The absence of a TA is a predictive factor for the presence of COM stones (p = 0.008). Hence, the association of NCHCT and Doppler enables the accurate classification of the five types of stones in vitro. Copyright © 2012 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Stone size limits the use of Hounsfield units for prediction of calcium oxalate stone composition.

PubMed

Stewart, Gregory; Johnson, Lewis; Ganesh, Halemane; Davenport, Daniel; Smelser, Woodson; Crispen, Paul; Venkatesh, Ramakrishna

2015-02-01

To evaluate the role of stone size in predicting urinary calculus composition using Hounsfield units on noncontrasted computed tomography (CT) scan. A retrospective review was performed for all patients who underwent ureteroscopy or percutaneous nephrolithotomy during a 1-year period, had a stone analysis performed, and had CT imaging available for review. All CT scans were reviewed by a board-certified radiologist. Variables evaluated included age, sex, body mass index, stone size, stone location, Hounsfield units (HUs), and stone composition. We identified a total of 91 patients (41 men and 50 women) with CT imaging and stone analysis available for review. Stone analysis showed 41 calcium oxalate monohydrate (CaOxMH), 13 calcium oxalate dihydrate, 29 calcium phosphate, 5 uric acid, 2 struvite, and 1 cystine stone. Average age was 46 years, and average body mass index was 32 kg/m2. Measured HUs varied significantly with size for CaOxMH and calcium oxalate dihydrate stones (P values <.05), but not for calcium phosphate stones (P = .126). Using a CaOxMH identification value of 700-1000 HUs, 28 of 41 stone compositions (68%) would not have been correctly identified, including all 10 (100%) small (<5 mm) stones, 13 of 22 (59%) medium (5-10 mm) stones, and 5 of 9 large (>10 mm) stones (55%). For calcium stones, the ability of CT HUs to predict stone composition was limited, likely due to the mixed stone composition. Within a cohort of CaOxMH stone formers, measured HUs varied linearly with stone size. All stones <5 mm were below thresholds for CaOxMH composition. Copyright © 2015 Elsevier Inc. All rights reserved.

Viscous-sludge sample collector

DOEpatents

Not Available

1979-01-01

A vertical core sample collection system for viscous sludge is disclosed. A sample tube's upper end has a flange and is attached to a piston. The tube and piston are located in the upper end of a bore in a housing. The bore's lower end leads outside the housing and has an inwardly extending rim. Compressed gas, from a storage cylinder, is quickly introduced into the bore's upper end to rapidly accelerate the piston and tube down the bore. The lower end of the tube has a high sludge entering velocity to obtain a full-length sludge sample without disturbing strata detail. The tube's downward motion is stopped when its upper end flange impacts against the bore's lower end inwardly extending rim.

Retention sleeve for a thermal medium carrying tube in a gas turbine

DOEpatents

Lathrop, Norman Douglas; Czachor, Robert Paul

2003-01-01

Multiple tubes are connected to steam supply and spent cooling steam return manifolds for supplying cooling steam to buckets and returning spent cooling steam from the buckets to the manifolds, respectively. The tubes are prevented from axial movement in one direction by flanges engaging end faces of the spacer between the first and second-stage wheels. Retention sleeves are disposed about cantilevered ends of the tubes. One end of the retention sleeve engages an enlarged flange on the tube, while an opposite end is spaced axially from an end face of the adjoining wheel, forming a gap, enabling thermal expansion of the tubes and limiting axial displacement of the tube in the opposite direction.

Viscous sludge sample collector

DOEpatents

Beitel, George A [Richland, WA

1983-01-01

A vertical core sample collection system for viscous sludge. A sample tube's upper end has a flange and is attached to a piston. The tube and piston are located in the upper end of a bore in a housing. The bore's lower end leads outside the housing and has an inwardly extending rim. Compressed gas, from a storage cylinder, is quickly introduced into the bore's upper end to rapidly accelerate the piston and tube down the bore. The lower end of the tube has a high sludge entering velocity to obtain a full-length sludge sample without disturbing strata detail. The tube's downward motion is stopped when its upper end flange impacts against the bore's lower end inwardly extending rim.

Ingestion resistant seal assembly

DOEpatents

Little, David A [Chuluota, FL

2011-12-13

A seal assembly limits gas leakage from a hot gas path to one or more disc cavities in a gas turbine engine. The seal assembly includes a seal apparatus associated with a blade structure including a row of airfoils. The seal apparatus includes an annular inner shroud associated with adjacent stationary components, a wing member, and a first wing flange. The wing member extends axially from the blade structure toward the annular inner shroud. The first wing flange extends radially outwardly from the wing member toward the annular inner shroud. A plurality of regions including one or more recirculation zones are defined between the blade structure and the annular inner shroud that recirculate working gas therein back toward the hot gas path.

High speed cylindrical roller bearing analysis, SKF computer program CYBEAN. Volume 2: User's manual

NASA Technical Reports Server (NTRS)

Kleckner, R. J.; Pirvics, J.

1978-01-01

The CYBEAN (Cylindrical Bearing Analysis) was created to detail radially loaded, aligned and misaligned cylindrical roller bearing performance under a variety of operating conditions. Emphasis was placed on detailing the effects of high speed, preload and system thermal coupling. Roller tilt, skew, radial, circumferential and axial displacement as well as flange contact were considered. Variable housing and flexible out-of-round outer ring geometries, and both steady state and time transient temperature calculations were enabled. The complete range of elastohydrodynamic contact considerations, employing full and partial film conditions were treated in the computation of raceway and flange contacts. Input and output architectures containing guidelines for use and a sample execution are detailed.

High power microwave components for space communications satellite

NASA Technical Reports Server (NTRS)

Jankowski, H.; Geia, A.

1972-01-01

Analyzed, developed, and tested were high power microwave components for communications satellites systems. Included were waveguide and flange configurations with venting, a harmonic filter, forward and reverse power monitors, electrical fault sensors, and a diplexer for two channel simultaneous transmission. The assembly of 8.36 GHz components was bench tested, and then operated for 60 hours at 3.5 kW CW in a high vacuum. The diplexer was omitted from this test pending a modification of its end irises. An RF leakage test showed only that care is required at flange junctions; all other components were RF tight. Designs were extrapolated for 12 GHz and 2.64 GHz high power satellite systems.

Bladder stones after bladder augmentation are not what they seem.

PubMed

Szymanski, Konrad M; Misseri, Rosalia; Whittam, Benjamin; Lingeman, James E; Amstutz, Sable; Ring, Joshua D; Kaefer, Martin; Rink, Richard C; Cain, Mark P

2016-04-01

Bladder and renal calculi after bladder augmentation are thought to be primarily infectious, yet few studies have reported stone composition. The primary aim was to assess bladder stone composition after augmentation, and renal stone composition in those with subsequent nephrolithiasis. The exploratory secondary aim was to screen for possible risk factors for developing infectious stones. Patients treated for bladder stones after bladder augmentation at the present institution between 1981 and 2012 were retrospectively reviewed. Data were collected on demographics, surgeries and stone composition. Patients without stone analysis were excluded. Stones containing struvite, carbonate apatite or ammonium acid ureate were classified as infectious. The following variables were analyzed for a possible association with infectious bladder stone composition: gender, history of cloacal exstrophy, ambulatory status, nephrolithiasis, recurrent urea-splitting urinary tract infections, first vs recurrent stones, timing of presentation with a calculus, history of bladder neck procedures, catheterizable channel and vesicoureteral reflux. Fisher's exact test was used for analysis. Of the 107 patients with bladder stones after bladder augmentation, 85 met inclusion criteria. Median age at augmentation was 8.0 years (follow-up 10.8 years). Forty-four patients (51.8%) recurred (14 multiple recurrences, 143 bladder stones). Renal calculi developed in 19 (22.4%) patients with a bladder stone, and 10 (52.6%) recurred (30 renal stones). Overall, 30.8% of bladder stones were non-infectious (Table). Among patients recurring after an infectious bladder stone, 30.4% recurred with a non-infectious one. Among patients recurring after a non-infectious stone, 84.6% recurred with a non-infectious one (P = 0.005). Compared with bladder stones, renal stones were more likely to be non-infectious (60.0%, P = 0.003). Of patients with recurrent renal calculi after an infectious stone, 40.0% recurred with a non-infectious one. No clinical variables were significantly associated with infectious stone composition on univariate (≥0.28) or bivariate analysis (≥0.36). This study had several limitations: it was not possible to accurately assess adherence with bladder irrigations, and routine metabolic evaluations were not performed. The findings may not apply to patients in all clinical settings. While stone analysis was available for 3/4 of the stones, similar rates of incomplete stone analyses have been reported in other series. In patients with bladder augmentation, 1/3 of bladder stones and >1/2 of renal stones were non-infectious. Furthermore, an infectious stone does not imply an infectious recurrent stone and no known clinical variables appear to be associated with stone composition, suggesting that there is a possible metabolic component in stone formation after bladder augmentation. Copyright © 2015 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Renal stone composition does not affect the outcome of percutaneous nephrolithotomy in children.

PubMed

Kaygısız, Onur; Türegün, Fethi Ahmet; Satar, Nihat; Özen, Ender; Toksöz, Serdar; Doğan, Hasan Serkan; Pişkin, Mehmet Mesut; İzol, Volkan; Sarıkaya, Şaban; Kılıçarslan, Hakan; Çiçek, Tufan; Öztürk, Ahmet; Tekgül, Serdar; Önal, Bülent

2018-05-14

We sought to investigate the association between renal stone composition and percutaneous nephrolithotomy outcomes in pediatric patients and define the characterization of the stone composition. The data of 1157 children who underwent percutaneous nephrolithotomy between 1991 and 2012 were retrieved from the multicenter database of the Turkish Pediatric Urology Society. The study population comprised 359 children (160 girls, 199 boys) with stone analyses. Patients were divided into five groups according to the stone composition [group 1: calcium oxalate; group 2: calcium phosphate; group 3: infection stones (magnesium ammonium phosphate, ammonium urate); group 4: cystine; group 5: uric acid, xanthine stones]. Patient characteristics, perioperative, postoperative, and stone characteristics were compared considering the stone composition. There were no significant differences between the groups concerning age, sex, side involved, preoperative hematocrit levels, and solitary renal unit. Patients with cystine stones were more likely to have a history of stone treatment. Groups 2 and 5 had mostly solitary stones. However, group 3 had staghorn stone more often, and group 4 frequently had multiple stones. Overall stone-free rate (79.4%) was similar among the groups. Although stone composition was related to blood transfusion and prolonged operative and fluoroscopy screening times on univariate analysis, it was not a significant predictor of them on multivariate analysis. Stone composition was not a predictor of outcomes of pediatric percutaneous nephrolithotomy. However, cystine and infection stones, which are larger and filled multiple calyxes due to the nature of stone forming, were more challenging cases that need multiple tracts.

Stone heterogeneity index on single-energy noncontrast computed tomography can be a positive predictor of urinary stone composition

PubMed Central

Lee, Jong Soo; Cho, Kang Su; Lee, Seung Hwan; Yoon, Young Eun; Kang, Dong Hyuk; Jeong, Won Sik; Jung, Hae Do; Kwon, Jong Kyou

2018-01-01

The aim of this study was to investigate the correlation between stone composition and single-energy noncontrast computed tomography (NCCT) parameters, including stone heterogeneity index (SHI) and mean stone density (MSD), in patients with urinary calculi. We retrospectively reviewed medical records of 255 patients who underwent operations or procedures for urinary stones or had spontaneous stone passage between December 2014 and October 2015. Among these, 214 patients with urinary calculi who underwent NCCT and stone composition analyses were included in the study. Maximal stone length (MSL), mean stone density (MSD), and stone heterogeneity index (SHI) were determined on pretreatment NCCT. The mean MSD (454.68±177.80 HU) and SHI (115.82±96.31 HU) of uric acid stones were lower than those of all other types. Based on post hoc tests, MSD was lower for uric acid stones than for the other types (vs. CaOx: P<0.001; vs. infection stones: P<0.001). SHI was lower for uric acid stones than for the other types (vs. CaOx: P<0.001; vs. infection stones: P<0.001) Receiver operating characteristic curves of uric acid stones for MSD and SHI demonstrated that SHI (cut-off value: 140.4 HU) was superior to MSD (cut-off value: 572.3 HU) in predicting uric acid stones (P<0.001). PMID:29649219

MECHANISMS OF HUMAN KIDNEY STONE FORMATION

PubMed Central

Evan, Andrew P.; Worcester, Elaine M.; Coe, Fredric L.; Williams, James; Lingeman, James E.

2014-01-01

The precise mechanisms of kidney stone formation and growth are not completely known, even though human stone disease appears to be one of the oldest diseases known to medicine. With the advent of the new digital endoscope and detailed renal physiological studies performed on well phenotyped stone formers, substantial advances have been made in our knowledge of the pathogenesis of the most common type of stone former, the idiopathic calcium oxalate stone former (ICSF) as well as nine other stone forming groups. The observations from our group on human stone formers and those of others on model systems have suggested four entirely different pathways for kidney stone formation. Calcium oxalate stone growth over sites of Randall’s plaque appear to be the primary mode of stone formation for those patients with hypercalciuria. Overgrowths off the ends of Bellini duct plugs have been noted in most stone phenotypes, do they result in a clinical stone? Micro-lith formation does occur within the lumens of dilated inner medullary collecting ducts of cystinuric stone formers and appear to be confined to this space. Lastly, cystinuric stone formers also have numerous small, oval, smooth yellow appearing calyceal stones suggestive of formation in free solution. The scientific basis for each of these four modes of stone formation are reviewed and used to explore novel research opportunities. PMID:25108546

The Damage To The Armour Layer Due To Extreme Waves

NASA Astrophysics Data System (ADS)

Oztunali Ozbahceci, Berguzar; Ergin, Aysen; Takayama, Tomotsuka

2010-05-01

The sea waves are not regular but random and chaotic. In order to understand this randomness, it is common to make individual wave analysis in time domain or spectral analysis in frequency domain. Characteristic wave heights like Hmax, H%2,H1-10, H1-3, Hmean are obtained through individual wave analysis in time domain. These characteristic wave heights are important because they are used in the design of different type of coastal structures. It is common to use significant wave height, H1-3,for the design of rubble mound structures. Therefore, only spectrally derived or zero-crossing significant wave height is usually reported for the rubble mound breakwaters without any information on larger waves. However, even the values of H1-3are similar; some train of irregular waves may exhibit a large fluctuation of instantaneous wave energy, while another train may not show such a fluctuation (Goda, 1998). Moreover, freak or rogue wave, simply defined as the wave exceeding at least twice the significant wave height may also occur. Those larger waves were called as extreme waves in this study and the effect of extreme waves on the damage to the armour layer of rubble mound breakwaters was investigated by means of hydraulic model experiment. Rock armored rubble mound breakwater model with 1:1.5 slope was constructed in the wave channel of Hydraulics Laboratory of the Disaster Prevention Research Institute of Kyoto University, Japan. The model was consisted of a permeable core layer, a filter and armour layer with two stones thicknesses. Size of stones were same for both of the slopes as Dn50(armour)=0.034m, Dn50(filter)=0.021m and Dn50(core)=0.0148m for armour, filter and core layers, respectively. Time series which are approximately equal to 1000 waves, with similar significant wave height but different extreme wave height cases were generated. In order to generate necessary time series in the wave channel, they were firstly computed by numerically. For the numerical computation of wave time series, Deterministic Spectral Amplitude (DSA) model with FFT algorithm was used. It is possible to get thousands of time series which have different wave statistics in DSA model by setting up the target spectrum and using random numbers for phase angles (Tuah et.al. 1982). Multi-reflection in the wave channel was minimized by the absorption mode of wave generator. Incident wave energy spectrum was obtained by using the separation method introduced by Goda and Suzuki (1976). Three wave gauges in front of the model were used for the separation. Individual wave heights were determined by zero-up crossing method after obtaining incident wave train. After each test, damage of the breakwater was calculated. Van der Meer's (1988) definition of damage level, S, was used in the calculations as: S= Ae/Dn502 (1) where; Ae= Eroded area, Dn50: nominal diameter of armour stone In order to get eroded area, the profile of armour layer was measured by laser equipment through nine lines along the section. Results of the experiments indicate that the higher the extreme waves are, the more destructive the wave train is, even the data is scattered. The damage was also calculated by using Van der Meer's formulae (1988) and compared with the experimental results. The comparison shows that the damages are more than the expected results in the cases where at least one wave height in the train is higher than the twice of H1-3. In fact, the damage results calculated by Van der Meer's formulae form the lower boundary for the higher extreme wave cases. It is also found that the damage is highly correlated to the ratios of characteristic waves like H1-10/H1-3 or H1-20/H1-3. Therefore, the parameter αextreme covering the effect of all extreme waves is proposed. References Goda, Y. and Suzuki, Y. (1976) .' Estimation of Incident and Reflected Waves in Random wave experiments.' Proc. 15th. Int. Conf. Coastal Engg., Hawai,1976, pp.828-845. Goda Y. (1998), 'An Overview of Coastal Engineering With Emphasis On Random Wave Approach', Coastal Engineering Journal, vol.40, No:1, pp. 1-21, World Scientific Pub. and JSCE Tuah, H, Hudspeth, RT (1982).'Comparisons of Numerical Random Sea Simulations,' Jour. Waterway, Port, Coastal and Ocean Engineering, Vol. 108, pp 569-584. Van der Meer, J.W,(1988). Rock Slopes and gravel beaches under wave attack. Ph.D thesis, Netherland.

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

Davis, J.C.; Reiss, R.J.; Rica, A.F.

There is disclosed an aseptic flexible walled container having a rigid fitment member cooperative with an aseptic filling apparatus and including a neck, outer flanges surrounding the neck, a frangible membrane and an outer end rim receptive of an hermetically sealed lid. The neck is formed with an internal chamferred seating shoulder for fluid-tight engagement with a fill tube. One outer flange cooperates with clamping jaws of the aseptic filling apparatus for detachably sealing the fitment to a sterilizing chamber and placing it in position for insertion of the filling tube which ruptures the membrane and permits the aseptic introductionmore » of product to the container's interior. The other outer flange is secured to an opening in a wall of the flexible container. The joined fitment and container are presterilized prior to filling. Selected materials for the multi-ply container walls and the fitment permit the container to withstand gamma ray and other sterilization treatment, heat and pressure while maintaining required strength. After the container is aseptically filled, such as with flowable food product, the fill tube is withdrawn and a lid is hermetically sealed onto the rim of the fitment. A heat shield adjacent a container wall surrounds the fitment to protect the container from excessive heat generated by the associated filling apparatus during filling.« less

Adhesive Bonding and Corrosion Protection of a Die Cast Magnesium Automotive Door

NASA Astrophysics Data System (ADS)

Bretz, G. T.; Lazarz, K. A.; Hill, D. J.; Blanchard, P. J.

It is well known that magnesium alloys, in close proximity to other alloys, are susceptible to galvanic corrosion. Combined with this fact, in automotive applications, it is rare that magnesium will be present in the absence of other alloys such as steel or aluminum. Therefore, in wet applications, where the galvanic cell is completed, it is necessary to isolate the magnesium in order to prevent accelerated corrosion. There are numerous commercial pre-treatments available for magnesium, however this paper focuses on conversion coatings in conjunction with a spray powder coat. By means of example, results for a hem flange joint on an AM50 die cast magnesium door structure will be presented. The outer door skin is an aluminum alloy hemmed around a cast magnesium flange. An adhesive is used between the inner and outer to help with stiffness and NVH (Noise, Vibration and Harshness). Results from bonded lap-shear coupon tests that have been exposed to accelerated corrosion cycles are presented. A second phase of this work considered a surrogate hem flange coupon, which was similarly exposed to the same accelerated corrosion cycle. Results from both of these tests are presented within this paper along with a discussion as to their suitability for use within automotive applications.

Investigation into Z-Pin Reinforced Composite Skin/Stiffener Debond under Monotonic and Cyclic Bending

NASA Astrophysics Data System (ADS)

Zhang, Xiangyang; Li, Yong; Van Hoa, Suong; Xiao, Jun; Chu, Qiyi

2018-02-01

Skin/stiffener debonding has been a longstanding concern for the users of stiffened composite panels in long-term service. Z-pinning technology is an emerging solution to reinforce the composite assembly joints. This work experimentally characterizes the progressive debonding of Z-pinned skin/stiffener interface with the skin under static bend loading. The three-stage failure process is identified as: flange edge debonding, pin/laminate debonding, and ultimate structural failure. Three different distribution patterns were compared in terms of the static debonding properties revealed the affirmative fact that locating pins in high normal stress regions, that is close to the flange edges in skin/stiffener structures, is more beneficial to utilize the full potential of Z-pinning reinforcement. The unit strip FE model was developed and demonstrated effective to analysis the effect of Z-pin distribution on the ultimate debond load. On the other hand, the evolution of fatigue cracks at Z-pinned skin/flange interface was investigated with a series of displacement-controlled fatigue bending tests and microscopic observations. Results show that Z-pinning postpones crack initiations at low displacement levels, and the remarkable crack-arresting function of pins enables the structure a prolonged fatigue life. However, pins become less effective when the maximum displacement exceeds the crack initiation level due to gradually pullout of pins.

Lignification of developing maize (Zea mays L.) endosperm transfer cells and starchy endosperm cells

PubMed Central

Rocha, Sara; Monjardino, Paulo; Mendonça, Duarte; da Câmara Machado, Artur; Fernandes, Rui; Sampaio, Paula; Salema, Roberto

2014-01-01

Endosperm transfer cells in maize have extensive cell wall ingrowths that play a key role in kernel development. Although the incorporation of lignin would support this process, its presence in these structures has not been reported in previous studies. We used potassium permanganate staining combined with transmission electron microscopy – energy dispersive X-ray spectrometry as well as acriflavine staining combined with confocal laser scanning microscopy to determine whether the most basal endosperm transfer cells (MBETCs) contain lignified cell walls, using starchy endosperm cells for comparison. We investigated the lignin content of ultrathin sections of MBETCs treated with hydrogen peroxide. The lignin content of transfer and starchy cell walls was also determined by the acetyl bromide method. Finally, the relationship between cell wall lignification and MBETC growth/flange ingrowth orientation was evaluated. MBETC walls and ingrowths contained lignin throughout the period of cell growth we monitored. The same was true of the starchy cells, but those underwent an even more extensive growth period than the transfer cells. Both the reticulate and flange ingrowths were also lignified early in development. The significance of the lignification of maize endosperm cell walls is discussed in terms of its impact on cell growth and flange ingrowth orientation. PMID:24688487

QTL mapping of flag leaf-related traits in wheat (Triticum aestivum L.).

PubMed

Liu, Kaiye; Xu, Hao; Liu, Gang; Guan, Panfeng; Zhou, Xueyao; Peng, Huiru; Yao, Yingyin; Ni, Zhongfu; Sun, Qixin; Du, Jinkun

2018-04-01

QTL controlling flag leaf length, flag leaf width, flag leaf area and flag leaf angle were mapped in wheat. This study aimed to advance our understanding of the genetic mechanisms underlying morphological traits of the flag leaves of wheat (Triticum aestivum L.). A recombinant inbred line (RIL) population derived from ND3331 and the Tibetan semi-wild wheat Zang1817 was used to identify quantitative trait loci (QTLs) controlling flag leaf length (FLL), flag leaf width (FLW), flag leaf area (FLA), and flag leaf angle (FLANG). Using an available simple sequence repeat genetic linkage map, 23 putative QTLs for FLL, FLW, FLA, and FLANG were detected on chromosomes 1B, 2B, 3A, 3D, 4B, 5A, 6B, 7B, and 7D. Individual QTL explained 4.3-68.52% of the phenotypic variance in different environments. Four QTLs for FLL, two for FLW, four for FLA, and five for FLANG were detected in at least two environments. Positive alleles of 17 QTLs for flag leaf-related traits originated from ND3331 and 6 originated from Zang1817. QTLs with pleiotropic effects or multiple linked QTL were also identified on chromosomes 1B, 4B, and 5A; these are potential target regions for fine-mapping and marker-assisted selection in wheat breeding programs.

The Effect of Stone Composition on the Efficacy of Retrograde Intrarenal Surgery: Kidney Stones 1 - 3 cm in Diameter.

PubMed

Xue, Yuquan; Zhang, Peng; Yang, Xiaojie; Chong, Tie

2015-05-01

The goal of this study was to analyze the effect of stone composition on the efficacy of retrograde intrarenal surgery (RIRS) with kidney stones of 1-3 cm, 1-2 cm, and 2-3 cm in diameter. We undertook a retrospective analysis of 74 patients with kidney stones who underwent RIRS. The patients were divided into two groups based on stone composition: Group I (n=47) (calcium oxalate monohydrate and calcium phosphate) was the hard to fragment stone group and group II (n=27) (calcium oxalate dihydrate, magnesium ammonium phosphate, and uric acid) was the easy to fragment stone group. Forty-six patients with kidney stones 1 to 2 cm in diameter were divided into group A (n=30) (smaller than 20 mm, hard to fragment stones) and group B (n=16) (smaller than 20 mm, easy to fragment stones). Twenty-eight patients with stones 2 to 3 cm in diameter were divided into group C (n=17) (larger than 20 mm, hard to fragment stones) and group D (n=11) (larger than 20 mm, easy-to-crush stones). The stone clearance rates of group I and group II were 66.0% and 88.9%, respectively (P<0.05). The stone clearance rates of group A and group B were 73.3% and 100% (P<0.05). The stone clearance rates of group C and group D were 52.9% and 72.7%, respectively. Stone composition has a significant impact on the efficacy of RIRS in the management of 1 to 3 cm kidney stones. For 2-3 cm calcium oxalate dihydrate stones, uric acid stones, and magnesium ammonium phosphate stones, the outcome of RIRS treatment was relatively good, and RIRS is recommended.

CT visible internal stone structure, but not Hounsfield unit value, of calcium oxalate monohydrate (COM) calculi predicts lithotripsy fragility in vitro.

PubMed

Zarse, Chad A; Hameed, Tariq A; Jackson, Molly E; Pishchalnikov, Yuri A; Lingeman, James E; McAteer, James A; Williams, James C

2007-08-01

Calcium oxalate monohydrate (COM) stones are often resistant to breakage using shock wave (SW) lithotripsy. It would be useful to identify by computed tomography (CT) those COM stones that are susceptible to SW's. For this study, 47 COM stones (4-10 mm in diameter) were scanned with micro CT to verify composition and also for assessment of heterogeneity (presence of pronounced lobulation, voids, or apatite inclusions) by blinded observers. Stones were then placed in water and scanned using 64-channel helical CT. As with micro CT, heterogeneity was assessed by blinded observers, using high-bone viewing windows. Then stones were broken in a lithotripter (Dornier Doli-50) over 2 mm mesh, and SW's counted. Results showed that classification of stones using micro CT was highly repeatable among observers (kappa = 0.81), and also predictive of stone fragility. Stones graded as homogeneous required 1,874 +/- 821 SW/g for comminution, while stones with visible structure required half as many SW/g, 912 +/- 678. Similarly, when stones were graded by appearance on helical CT, classification was repeatable (kappa = 0.40), and homogeneous stones required more SW's for comminution than did heterogeneous stones (1,702 +/- 993 SW/g, compared to 907 +/- 773). Stone fragility normalized to stone size did not correlate with Hounsfield units (P = 0.85). In conclusion, COM stones of homogeneous structure require almost twice as many SW's to comminute than stones of similar mineral composition that exhibit internal structural features that are visible by CT. This suggests that stone fragility in patients could be predicted using pre-treatment CT imaging. The findings also show that Hounsfield unit values of COM stones did not correlate with stone fragility. Thus, it is stone morphology, rather than X-ray attenuation, which correlates with fragility to SW's in this common stone type.

A comparative study of mud-like and coralliform calcium carbonate gallbladder stones.

PubMed

Ma, Rui-Hong; Luo, Xiao-Bing; Wang, Xiao-Feng; Qiao, Tie; Huang, Hai-Yi; Zhong, Hai-Qiang

2017-07-01

To gain insight to underlying mechanism of the formation of calcium carbonate (CaCO 3 ) gallbladder stones, we did comparative study of stones with mud appearance and those with coralliform appearance. A total of 93 gallbladder stones with mud appearance and 50 stones with coralliform appearance were analyzed. The appearance, color, texture, and the detection of Clonorchis sinensis eggs by microscopic examination were compared between the two groups. Then, the material compositions of stones were analyzed using Fourier Transform Infrared spectroscopy and the spectrogram characteristics were compared. Moreover, microstructure characteristics of the two kinds of stones were observed and compared with Scanning Electron Microscopy. Mud-like gallbladder stones were mainly earthy yellow or brown with brittle or soft texture, while coralliform stones were mainly black with extremely hard texture, the differences between the two groups was significant (p < .05). The analytic results of FTIR spectroscopy showed that 95.7% (89/93) of the mud-like gallbladder stones were CaCO 3 stones, and mainly aragonite; while all of the coralliform stones were CaCO 3 stones, and mainly calcite (p < .05). Meanwhile, microscopic examination indicated that the detection rate of Clonorchis sinensis eggs in mud-like CaCO 3 stones was lower than that in coralliform CaCO 3 stones (p < .05), and that in aragonite CaCO 3 stones was lower than that in calcite CaCO 3 stones(p < .05). Mud-like CaCO 3 stones mainly happened to patients with cystic duct obstruction. Clonorchis sinensis infection was mainly associated with coralliform (calcite) CaCO 3 stones. Cystic duct obstruction was mainly associated with mud-like (aragonite) CaCO 3 stones. © 2017 Wiley Periodicals, Inc.

Is There A Difference Between Presence of Single Stone And Multiple Stones in Flexible Ureterorenoscopy And Laser Lithotripsy For Renal Stone Burden < 300mm2 ?

PubMed

Ozgor, Faruk; Kucuktopcu, Onur; Ucpinar, Burak; Gurbuz, Zafer Gokhan; Sarilar, Omer; Berberoglu, Ahmet Yalcin; Baykal, Murat; Binbay, Murat

2016-01-01

In this study, we aim to evaluate and compare the effectiveness of flexible ureterorenoscopy (f-URS) for solitary and multiple renal stones with < 300 mm2 stone burden. Patients' charts who treated with f-URS for kidney stone between January 2010 and June 2015 were reviewed, retrospectively. Patients with solitary kidney stones (n:111) were enrolled in group 1. We selected 111 patients with multiple kidney stones to serve as the control group and the patients were matched at a 1:1 ratio with respect to the patient's age, gender, body mass index and stone burden. Additionally, patients with multiple stones were divided into two groups according to the presence or abscence of lower pole stones. Stone free status was accepted as complete stone clearence and presence of residual fragments < 2 mm. According to the study design; age, stone burden, body mass index were comparable between groups. The mean operation time was longer in group 2 (p= 0.229). However, the mean fluoroscopy screening time in group 1 and in group 2 was 2.1±1.7 and 2.6±1.5 min, respectively and significantly longer in patients with multiple renal stones (P=0.043). The stone-free status was significantly higher in patients with solitary renal stones after a single session procedure (p=0.02). After third month follow up, overall success rate was 92.7% in Group 1 and 86.4% in Group 2. Our study revealed that F-URS achieved better stone free status in solitary renal stones < 300 mm2. However, outcomes of F-URS were acceptable in patients with multiple stones. Copyright® by the International Brazilian Journal of Urology.

Bacteria entombed in the center of cholesterol gallstones induce fewer infectious manifestations than bacteria in the matrix of pigment stones.

PubMed

Stewart, Lygia; Griffiss, J McLeod; Jarvis, Gary A; Way, Lawrence W

2007-10-01

The clinical significance of bacteria in the pigment centers of cholesterol stones is unknown. We compared the infectious manifestations and characteristics of bacteria from pigment stones and predominantly cholesterol stones. Three hundred forty patients were studied. Bile was cultured. Gallstones were cultured and examined with scanning electron microscopy. Level of bacterial immunoglobulin G (bile, serum), complement killing, and tumor necrosis factor-alpha production were determined. Twenty-three percent of cholesterol stones and 68% of pigment stones contained bacteria (P < 0.0001). Stone culture correlated with scanning electron microscopy results. Pigment stone bacteria were more often present in bile and blood. Cholesterol stone bacteria caused more severe infections (19%) than sterile stones (0%), but less than pigment stone bacteria (57%) (P < 0.0001). Serum and bile from patients with cholesterol stone bacteria had less bacterial-specific immunoglobulin G. Cholesterol stone bacteria produced more slime. Pigment stone bacteria were more often killed by a patient's serum. Tumor necrosis factor-alpha production of the groups was similar. Bacteria are readily cultured from cholesterol stones with pigment centers, allowing for analysis of their virulence factors. Bacteria sequestered in cholesterol stones cause infectious manifestations, but less than bacteria in pigment stones. Possibly because of their isolation, cholesterol stone bacteria were less often present in bile and blood, induced less immunoglobulin G, were less often killed by a patient's serum, and demonstrated fewer infectious manifestations than pigment stone bacteria. This is the first study to analyze the clinical relevance of bacteria within cholesterol gallstones.

The Guy's stone score--grading the complexity of percutaneous nephrolithotomy procedures.

PubMed

Thomas, Kay; Smith, Naomi C; Hegarty, Nicholas; Glass, Jonathan M

2011-08-01

To report the development and validation of a scoring system, the Guy's stone score, to grade the complexity of percutaneous nephrolithotomy (PCNL). Currently, no standardized method is available to predict the stone-free rate after PCNL. The Guy's stone score was developed through a combination of expert opinion, published data review, and iterative testing. It comprises 4 grades: grade I, solitary stone in mid/lower pole or solitary stone in the pelvis with simple anatomy; grade II, solitary stone in upper pole or multiple stones in a patient with simple anatomy or a solitary stone in a patient with abnormal anatomy; grade III, multiple stones in a patient with abnormal anatomy or stones in a caliceal diverticulum or partial staghorn calculus; grade IV, staghorn calculus or any stone in a patient with spina bifida or spinal injury. It was assessed for reproducibility using the kappa coefficient and validated on a prospective database of 100 PCNL procedures performed in a tertiary stone center. The complications were graded using the modified Clavien score. The clinical outcomes were recorded prospectively and assessed with multivariate analysis. The Guy's stone score was the only factor that significantly and independently predicted the stone-free rate (P = .01). It was found to be reproducible, with good inter-rater agreement (P = .81). None of the other factors tested, including stone burden, operating surgeon, patient weight, age, and comorbidity, correlated with the stone-free rate. The Guy's stone score accurately predicted the stone-free rate after PCNL. It was easy to use and reproducible. Copyright © 2011 Elsevier Inc. All rights reserved.

Incidence of kidney stones in kidney transplant recipients: A systematic review and meta-analysis

PubMed Central

Cheungpasitporn, Wisit; Thongprayoon, Charat; Mao, Michael A; Kittanamongkolchai, Wonngarm; Jaffer Sathick, Insara J; Dhondup, Tsering; Erickson, Stephen B

2016-01-01

AIM To evaluate the incidence and characteristics of kidney stones in kidney transplant recipients. METHODS A literature search was performed using MEDLINE, EMBASE, and Cochrane Database of Systematic Reviews from the inception of the databases through March 2016. Studies assessing the incidence of kidney stones in kidney transplant recipients were included. We applied a random-effects model to estimate the incidence of kidney stones. RESULTS Twenty one studies with 64416 kidney transplant patients were included in the analyses to assess the incidence of kidney stones after kidney transplantation. The estimated incidence of kidney stones was 1.0% (95%CI: 0.6%-1.4%). The mean duration to diagnosis of kidney stones after kidney transplantation was 28 ± 22 mo. The mean age of patients with kidney stones was 42 ± 7 years. Within reported studies, approximately 50% of kidney transplant recipients with kidney stones were males. 67% of kidney stones were calcium-based stones (30% mixed CaOx/CaP, 27%CaOx and 10%CaP), followed by struvite stones (20%) and uric acid stones (13%). CONCLUSION The estimated incidence of kidney stones in patients after kidney transplantation is 1.0%. Although calcium based stones are the most common kidney stones after transplantation, struvite stones (also known as “infection stones”) are not uncommon in kidney transplant recipients. These findings may impact the prevention and clinical management of kidney stones after kidney transplantation. PMID:28058231

Flexible Ureterorenoscopy for Treatment of Kidney Stones: Establishment as Primary Standard Therapy in a Tertiary Stone Center.

PubMed

Ising, Stephan; Labenski, Heike; Baltes, Stefan; Khaffaf, Aso; Thomas, Christian; Wiesner, Christoph

2015-01-01

To analyze the primary stone free rate (pSFR) of flexible ureterorenoscopy (fURS) in the treatment of renal stones and to identify clinical predictors for the primary freedom from renal stones. Two hundred and seventy five patients, who underwent fURS for kidney stones were analyzed. Index stone size was 6 mm. The stone was located in the lower calyx in 48%. Ureteral access sheath was used in 97%. Operation time was 35 min and primary stone clearance was 83%. pSFR increased from 74% in 2012 to 83% in 2013 and 90% in 2014 (p = 0.001). Preoperative stenting, index stone size, cumulative stone size, lithotripsy, ureteral access sheath and operation time were significantly correlated with the pSFR by univariate analysis. Multivariate regression analysis showed index stone size, cumulative stone size, ureteral access sheath and operation time as independent parameters for pSFR. fURS for kidney stones is safe with a high pSFR. Clinical parameters for pSFR are stone size, use of ureteral access sheath and operation time. In future, the effective use of fURS for the removal of kidney stones needs to be checked by prospective randomized trials. © 2015 S. Karger AG, Basel.

Pneumatic ureteroscopic lithotripsy: is it still a reasonable treatment option for multiple ureteric stones?

PubMed

Isen, Kenan

2012-01-01

To assess the efficacy and safety of ureteroscopic pneumatic lithotripsy for multiple ureteric stones. 36 patients with multiple ureteric stones were treated with ureteroscopic lithotripsy (URSL). A 8/9.8-Fr Wolf semirigid ureteroscope and pneumatic lithotripter were used for stone fragmentation. 87 stones were treated with URSL. Successful fragmentation was achieved in 77 (88.5%) of the stones. The retreatment rate was 11.5%. The stone-free rate (SFR) of lower ureteric stones (93.3%) and middle ureteric stones (87.5%) was significantly higher compared with upper (73.3%) ureteric stones (p < 0.05). For patients with stones less than 1 cm and greater than 1 cm, the SFR was 91.5 and 75.0%, respectively (p < 0.05). Perforation occurred in 1 patient, mucosal injury occurred in 5 and stone migration in 5. No long-term complication was observed in any patient. Ureteroscopic pneumatic lithotripsy is still a reasonable treatment option for multiple ureteric stones. The procedure has high success rates with minimal morbidity. However, success rate can be affected by stone size and ureteric location. Copyright © 2012 S. Karger AG, Basel.

The use of chemical treatments for improved comminution of artificial stones.

PubMed

Heimbach, D; Kourambas, J; Zhong, P; Jacobs, J; Hesse, A; Mueller, S C; Delvecchio, F C; Cocks, F H; Preminger, G M

2004-05-01

The acoustic and mechanical properties of various stone compositions are significantly different and thus result in varying degrees of fragility. Consequently, results to shock wave lithotripsy (SWL) are influenced accordingly. We report the results of a study of fragility of various stone compositions, and the influence on each stone's baseline physical properties and fragility when exposed to various chemolytic solutions. Before SWL artificial stones of differing compositions were irrigated with various chemolytic solutions. Calcium oxalate monohydrate (COM) stones were treated with ethylenediaminetetraacetic acid (EDTA), stones composed of magnesium ammonium phosphate hydrogen were treated with hemiacidrin, and stones made of uric acid (UA) were treated with tromethamine. Synthetic urine served as a control for all stone groups. Using an ultrasound transmission technique, longitudinal wave propagation speed was measured in all groups of artificial stones. Stone density was also measured by using a pycnometer (based on Archimedes' principle). Based on these measurements transverse (shear) wave speed (assuming a constant Poisson's ratio), wave impedance and dynamic mechanical properties of the artificial stones were calculated. Moreover, the microhardness of these artificial stones was measured, and fragility testing using SWL with and without pretreatment with the previously mentioned chemolytic solutions, was performed. Wave speed, wave impedance, dynamic mechanical properties and microhardness of EDTA treated COM stones and tromethamine treated UA stones were found to decrease compared to untreated (synthetic urine) control groups. The suggestion that chemolytic pretreatment increases stone fragility was verified by the finding of increased stone comminution after SWL testing. Combining this medical pretreatment and SWL, the findings demonstrate a significant impact of various solvents on stone comminution, in particular EDTA treated COM stones, tromethamine treated UA stones and hemiacidrin treated magnesium ammonium phosphate hydrogen stones. These data suggest that by altering the chemical environment of the fluid surrounding the stones it is possible to increase the fragility of renal calculi in vitro. These results indicate that appropriate chemical treatments may provide a useful adjunctive modality for improving the efficacy of stone comminution during shock wave lithotripsy.

Kidney stones during pregnancy: an investigation into stone composition.

PubMed

Ross, Ashley E; Handa, Shelly; Lingeman, James E; Matlaga, Brian R

2008-05-01

Kidney stones can be a source of considerable morbidity for pregnant women. Although there is a body of literature confirming that different stone compositions predominate for different age and sex cohorts, there have been no similar reports characterizing the nature of stone disease during pregnancy. We performed a multi-institutional study to define the composition of renal calculi diagnosed during pregnancy. We retrospectively reviewed the records from two stone referral centers of all patients diagnosed with a de novo kidney stone during pregnancy who underwent a procedure for the purpose of stone removal from June 2001 through September 2007. A total of 27 patients were identified, with a mean age of 26.8 years (range, 21-34). Twenty patients (74%) had no history of prior stone formation. Seven patients (26%) had previously formed stones, although none of these patients had a known kidney stone at the time they became pregnant. Stones were removed in the first, second, third trimester and immediately post-partum in 4, 52, 22, and 22% respectively. Stone removal was performed without complication in all cases. Analysis found that in 74% of all cases (20 patients) stones were composed predominantly of calcium phosphate (hydroxyapatite). In 26% of cases, (7 patients) the stones were composed predominantly of calcium oxalate. Of the seven patients with prior stone history, three patients had previously formed calcium phosphate stones and four patients had previously formed calcium oxalate stones. Calcium oxalate calculi are the most common stone in non-pregnant women of a comparable age as our subjects. However, our present data suggest that stones detected during pregnancy are most commonly composed of calcium phosphate (hydroxyapatite). Indeed, it is the minority of stones that are composed of calcium oxalate. Although the reason for this unusual preponderance of calcium phosphate calculi is unclear, physiologic alterations that occur during pregnancy may be influential.

Guaifenesin stone matrix proteomics: a protocol for identifying proteins critical to stone formation.

PubMed

Kolbach-Mandel, A M; Mandel, N S; Cohen, S R; Kleinman, J G; Ahmed, F; Mandel, I C; Wesson, J A

2017-04-01

Drug-related kidney stones are a diagnostic problem, since they contain a large matrix (protein) fraction and are frequently incorrectly identified as matrix stones. A urine proteomics study patient produced a guaifenesin stone during her participation, allowing us to both correctly diagnose her disease and identify proteins critical to this drug stone-forming process. The patient provided three random midday urine samples for proteomics studies; one of which contained stone-like sediment with two distinct fractions. These solids were characterized with optical microscopy and Fourier transform infrared spectroscopy. Immunoblotting and quantitative mass spectrometry were used to quantitatively identify the proteins in urine and stone matrix. Infrared spectroscopy showed that the sediment was 60 % protein and 40 % guaifenesin and its metabolite guaiacol. Of the 156 distinct proteins identified in the proteomic studies, 49 were identified in the two stone-components with approximately 50 % of those proteins also found in this patient's urine. Many proteins observed in this drug-related stone have also been reported in proteomic matrix studies of uric acid and calcium containing stones. More importantly, nine proteins were highly enriched and highly abundant in the stone matrix and 8 were reciprocally depleted in urine, suggesting a critical role for these proteins in guaifenesin stone formation. Accurate stone analysis is critical to proper diagnosis and treatment of kidney stones. Many matrix proteins were common to all stone types, but likely not related to disease mechanism. This protocol defined a small set of proteins that were likely critical to guaifenesin stone formation based on their high enrichment and high abundance in stone matrix, and it should be applied to all stone types.

Evaluation of stone volume distribution in renal collecting system as a predictor of stone-free rate after percutaneous nephrolithotomy: a retrospective single-center study.

PubMed

Atalay, Hasan Anıl; Canat, Lutfi; Bayraktarlı, Recep; Alkan, Ilter; Can, Osman; Altunrende, Fatih

2017-06-23

We analyzed our stone-free rates of PNL with regard to stone burden and its ratio to the renal collecting system volume. Data of 164 patients who underwent PNL were analyzed retrospectively. Volume segmentation of renal collecting system and stones were done using 3D segmentation software with the images obtained from CT data. Analyzed stone volume (ASV) and renal collecting system volume (RCSV) were measured and the ASV-to-RCSV ratio was calculated after the creation of a 3D surface volume rendering of renal stones and the collecting system. Univariate and multivariate statistical analyses were performed to determine factors affecting stone-free rates; also we assessed the predictive accuracy of the ASV-to-RCSV ratio using the receiving operating curve (ROC) and AUC. The stone-free rate of PNL monotherapy was 53% (164 procedures).The ASV-to-RCSV ratio and calyx number with stones were the most influential predictors of stone-free status (OR 4.15, 95% CI 2.24-7.24, <0.001, OR 2.62, 95% CI 1.38-4.97, p < 0.001, respectively). Other factors associated with the stone-free rate were maximum stone size (p < 0.029), stone surface area (p < 0.010), and stone burden volume (p < 0.001). Predictive accuracy of the ASV-to-RCSV ratio was AUC 0.76. Stone burden volume distribution in the renal collecting system, which is calculated using the 3D volume segmentation method, is a significant determinant of the stone-free rate before PCNL surgery. It could be used as a single guide variable by the clinician before renal stone surgery to predict extra requirements for stone clearance.

Cystine Stone Formers Have Impaired Health-Related Quality of Life Compared with Noncystine Stone Formers: A Case-Referent Study Piloting the Wisconsin Stone Quality of Life Questionnaire Among Patients with Cystine Stones.

PubMed

Streeper, Necole M; Wertheim, Margaret L; Nakada, Stephen Y; Penniston, Kristina L

2017-04-01

Cystinuria is a rare cause of urolithiasis. Affected patients have an earlier onset and more aggressive disease than patients with other stone etiologies. We assessed the health-related quality of life (HRQOL) of cystine stone-forming patients using the disease-specific Wisconsin Stone Quality of Life questionnaire (WISQOL). Cystine patients treated in our stone clinics (n = 12) completed the WISQOL; information about medical and stone histories was gathered. Patients were matched with noncystine stone formers (n = 12) for gender, age, and comorbidities. In addition, a second control group (n = 90), also from our institution and consisting of mixed calcium stone formers, was included. WISQOL responses were compared between groups. Cystine patients had significantly lower total WISQOL scores than noncystine patients. Compared with noncystine stone formers, cystine stone formers also had lower HRQOL scores for subscales (domains) related to social impact, emotional impact, disease impact, and vitality (p ≤ 0.04 for all). On specific items, cystine patients reported significantly more sleep problems (p = 0.02), more bother with nocturia (p = 0.03), and feeling tired or fatigued (p = 0.02). Among those with current stones, cystine patients scored lower than noncystine patients for total score and in two of four domains. Using a stone-specific questionnaire, patients with cystine stones have lower HRQOL compared with noncystine stone formers. Identifying and addressing specific areas of decrement in patients with cystine stones may improve disease management and patients' HRQOL.

Definition and Facts for Kidney Stones in Adults

MedlinePlus

... Eating, Diet, & Nutrition Clinical Trials Definition & Facts for Kidney Stones What are kidney stones? Kidney stones are hard, pebble-like pieces ... stone may get stuck along the way. Do kidney stones have another name? The scientific name for ...

Spontaneous passage of ureteral stones in patients with indwelling ureteral stents.

PubMed

Baumgarten, Lee; Desai, Anuj; Shipman, Scott; Eun, Daniel D; Pontari, Michel A; Mydlo, Jack H; Reese, Adam C

2017-10-01

To determine rates of spontaneous ureteral stone passage in patients with indwelling ureteral stents, and to identify factors associated with the spontaneous passage of stones while a ureteral stent is in place. From our institutional database, we identified patients who underwent ureteroscopic procedures for stone disease between January 1, 2013 and March 1, 2015. We compared the rates of spontaneous stone passage between patients who had previously undergone ureteral stent placement and those who had not. In patients with indwelling stents, multivariate logistic regression was performed to identify factors associated with spontaneous stone passage. A total of 194 patients met inclusion criteria. Spontaneous stone passage rates were similar in the stented (17/119, 14%) and non-stented (15/75, 20%) groups (p = 0.30). In bivariate analysis of stented patients, smaller stone size (p < 0.001) and distal stone location (p = 0.01) were significantly associated with spontaneous stone passage. Multivariate logistic regression analysis of stented patients showed that only small stone size was significantly associated with the likelihood of stone passage (p = 0.01), whereas stent duration, stone location, and stone laterality were not. A small, but clinically significant percentage of ureteral stones pass spontaneously with a ureteral stent in place. Small stone size is associated with an increased likelihood of spontaneous passage in patients with indwelling stents. These findings may help to identify patients who can potentially avoid additional surgical procedures for definitive stone removal after ureteral stent placement.

Extracorporeal shock wave lithotripsy of proximal and distal ureteral stones.

PubMed

Pettersson, B; Tiselius, H G

1988-01-01

Extracorporeal shock wave lithotripsy (ESWL) was used for treatment of 105 patients with ureteral stones. There were 77 stones in the upper part of the ureter, i.e. above the pelvic brim, and 28 in the lower part, i.e. below the sacroiliac joint. Successful fragmentation was attained in 101 (96%). In 93% of the patients with stones in the upper ureter and in 100% with stones in the lower ureter the fragments were eliminated completely. In 87% of the patients with stones in the upper ureter, a ureteral catheter was introduced under local anesthesia but without fluoroscopic control. It was thereby possible to remove 30% of the stones from the ureter to the kidney. For the remaining stones, saline was infused through the catheter during ESWL. For patients with stones in the lower part of the ureter, a ureteral catheter was passed in 79% and saline infused during treatment. Whereas some form of anesthesia was used for treatment of all upper ureteral stones, 89% of the treatments for lower ureteral stones were performed without anesthesia. Auxiliary procedures after ESWL were limited to four ureteral catheter manipulations for distal stones. Four proximal stones which remained unaffected by ESWL had to be treated by open surgery (3 stones) or percutaneous surgery (1 stone). Of 82 ureteric stones treated in situ the success fragmentation rate was 95%. The average number of ESWL sessions was 1.04 for both proximal and distal ureteral stones.

Metabolic Characteristics and Risks Associated with Stone Recurrence in Korean Young Adult Stone Patients.

PubMed

Kang, Ho Won; Seo, Sung Pil; Kim, Won Tae; Kim, Yong-June; Yun, Seok-Joong; Kim, Wun-Jae; Lee, Sang-Cheol

2017-08-01

The aim of this study was to assess the metabolic characteristics and risks of stone recurrence in young adult stone patients in Korea. The medical records of 1532 patients presenting with renal or ureteric stones at our stone clinic between 1994 and 2015 were retrospectively reviewed. Patients were grouped according to age (young adult, 18-29 years; intermediate onset, 30-59 years; old age, ≥60 years) at first presentation, and measurements of clinicometabolic characteristics and risks of stone recurrence were compared. Overall, excretion of urinary stone-forming substances was highest in the intermediate onset group, followed by the young adult and old age groups. Importantly, excretion of urinary citrate was lowest in the young adult group. Kaplan-Meier analyses identified a significant difference between the three age groups in terms of stone recurrence (log rank test, p < 0.001). Multivariate Cox regression analyses revealed that age at first stone presentation was an independent risk factor for stone recurrence. Urinary citrate excretion was an independent risk factor for stone recurrence in young adult stone patients. Younger age (18-29 years) at first stone presentation was a significant risk factor for stone recurrence, and urinary citrate excretion was an independent risk factor affecting recurrence in this group. Metabolic evaluation and potassium citrate therapy should be considered for young adult stone patients to prevent recurrence.

Appropriate kidney stone size for ureteroscopic lithotripsy: When to switch to a percutaneous approach

PubMed Central

Takazawa, Ryoji; Kitayama, Sachi; Tsujii, Toshihiko

2015-01-01

Flexible ureteroscopy (fURS) has become a more effective and safer treatment for whole upper urinary tract stones. Percutaneous nephrolithotomy (PNL) is currently the first-line recommended treatment for large kidney stones ≥ 20 mm and it has an excellent stone-free rate for large kidney stones. However, its invasiveness is not negligible considering its major complication rates. Staged fURS is a practical treatment for such large kidney stones because fURS has a minimal blood transfusion risk, short hospitalization and few restrictions on daily routines. However, as the stone size becomes larger, the stone-free rate decreases, and the number of operations required increases. Therefore, in our opinion, staged fURS is a practical option for kidney stones 20 to 40 mm. Miniaturized PNL combined with fURS should be considered to be a preferred option for stones larger than 40 mm. Moreover, URS is an effective treatment for multiple upper urinary tract stones. Especially for patients with a stone burden < 20 mm, URS is a favorable option that promises a high stone-free rate after a single session either unilaterally or bilaterally. However, for patients with a stone burden ≥ 20 mm, a staged operation should be considered to achieve stone-free status. PMID:25664253

Is scoring system of computed tomography based metric parameters can accurately predicts shock wave lithotripsy stone-free rates and aid in the development of treatment strategies?

PubMed Central

Badran, Yasser Ali; Abdelaziz, Alsayed Saad; Shehab, Mohamed Ahmed; Mohamed, Hazem Abdelsabour Dief; Emara, Absel-Aziz Ali; Elnabtity, Ali Mohamed Ali; Ghanem, Maged Mohammed; ELHelaly, Hesham Abdel Azim

2016-01-01

Objective: The objective was to determine the predicting success of shock wave lithotripsy (SWL) using a combination of computed tomography based metric parameters to improve the treatment plan. Patients and Methods: Consecutive 180 patients with symptomatic upper urinary tract calculi 20 mm or less were enrolled in our study underwent extracorporeal SWL were divided into two main groups, according to the stone size, Group A (92 patients with stone ≤10 mm) and Group B (88 patients with stone >10 mm). Both groups were evaluated, according to the skin to stone distance (SSD) and Hounsfield units (≤500, 500–1000 and >1000 HU). Results: Both groups were comparable in baseline data and stone characteristics. About 92.3% of Group A rendered stone-free, whereas 77.2% were stone-free in Group B (P = 0.001). Furthermore, in both group SWL success rates was a significantly higher for stones with lower attenuation <830 HU than with stones >830 HU (P < 0.034). SSD were statistically differences in SWL outcome (P < 0.02). Simultaneous consideration of three parameters stone size, stone attenuation value, and SSD; we found that stone-free rate (SFR) was 100% for stone attenuation value <830 HU for stone <10 mm or >10 mm but total number SWL sessions and shock waves required for the larger stone group were higher than in the smaller group (P < 0.01). Furthermore, SFR was 83.3% and 37.5% for stone <10 mm, mean HU >830, SSD 90 mm and SSD >120 mm, respectively. On the other hand, SFR was 52.6% and 28.57% for stone >10 mm, mean HU >830, SSD <90 mm and SSD >120 mm, respectively. Conclusion: Stone size, stone density (HU), and SSD is simple to calculate and can be reported by radiologists to applying combined score help to augment predictive power of SWL, reduce cost, and improving of treatment strategies. PMID:27141192

Fire effects on flaked stone, ground stone, and other stone artifacts [Chapter 4

Treesearch

Krista Deal

2012-01-01

Lithic artifacts can be divided into two broad classes, flaked stone and ground stone, that overlap depending on the defining criteria. For this discussion, flaked stone is used to describe objects that cut, scrape, pierce, saw, hack, etch, drill, or perforate, and the debris (debitage) created when these items are manufactured. Objects made of flaked stone include...

Novel ultrasound method to reposition kidney stones

PubMed Central

Shah, Anup; Owen, Neil R.; Lu, Wei; Cunitz, Bryan W.; Kaczkowski, Peter J.; Harper, Jonathan D.; Bailey, Michael R.; Crum, Lawrence A.

2011-01-01

The success of surgical management of lower pole stones is principally dependent on stone fragmentation and residual stone clearance. Choice of surgical method depends on stone size, yet all methods are subject to post-surgical complications resulting from residual stone fragments. Here we present a novel method and device to reposition kidney stones using ultrasound radiation force delivered by focused ultrasound and guided by ultrasound imaging. The device couples a commercial imaging array with a focused annular array transducer. Feasibility of repositioning stones was investigated by implanting artificial and human stones into a kidney-mimicking phantom that simulated a lower pole and collecting system. During experiment, stones were located by ultrasound imaging and repositioned by delivering short bursts of focused ultrasound. Stone motion was concurrently monitored by fluoroscopy, ultrasound imaging, and video photography, from which displacement and velocity were estimated. Stones were seen to move immediately after delivering focused ultrasound and successfully repositioned from the lower pole to the collecting system. Estimated velocities were on the order of 1 cm/s. This in vitro study demonstrates a promising modality to facilitate spontaneous clearance of kidney stones and increased clearance of residual stone fragments after surgical management. PMID:20967437

Development of lightweight aluminum compression panels reinforced by boron-epoxy infiltrated extrusions

NASA Technical Reports Server (NTRS)

Roy, P. A.; Mcelman, J. A.; Henshaw, J.

1973-01-01

Analytical and experimental studies were performed to evaluate the structural efficiencies afforded by the selective reinforcement of conventional aluminum compression panels with unidirectional boron epoxy composite materials. A unique approach for selective reinforcement was utilized called boron/epoxy infiltration. This technique uses extruded metal sections with preformed hollow voids into which unidirectional boron filaments are drawn and subsequently infiltrated with resin to form an integral part. Simplified analytical models were developed to investigate the behavior of stiffener webs with reinforced flanges. Theoretical results are presented demonstrating the effects of transverse shear, of the reinforcement, flange eccentricity and torsional stiffness in such construction. A series of 55 tests were conducted on boron-infiltrated rods and extruded structural sections.

New flange correction formula applied to interfacial resistance measurements of ohmic contacts to GaAs

NASA Technical Reports Server (NTRS)

Lieneweg, Udo; Hannaman, David J.

1987-01-01

A quasi-two-dimensional analytical model is developed to account for vertical and horizontal current flow in and adjacent to a square ohmic contact between a metal and a thin semiconducting strip which is wider than the contact. The model includes side taps to the contact area for voltage probing and relates the 'apparent' interfacial resistivity to the (true) interfacial resistivity, the sheet resistance of the semiconducting layer, the contact size, and the width of the 'flange' around the contact. This relation is checked against numerical simulations. With the help of the model, interfacial resistivities of ohmic contacts to GaAs were extracted and found independent of contact size in the range of 1.5-10 microns.

Cavity closure arrangement for high pressure vessels

DOEpatents

Amtmann, Hans H.

1981-01-01

A closure arrangement for a pressure vessel such as the pressure vessel of a high temperature gas-cooled reactor wherein a liner is disposed within a cavity penetration in the reactor vessel and defines an access opening therein. A closure is adapted for sealing relation with an annular mounting flange formed on the penetration liner and has a plurality of radially movable locking blocks thereon having outer serrations adapted for releasable interlocking engagement with serrations formed internally of the upper end of the penetration liner so as to effect high strength closure hold-down. In one embodiment, ramping surfaces are formed on the locking block serrations to bias the closure into sealed relation with the mounting flange when the locking blocks are actuated to locking positions.

Frame-mounted wire management device

DOEpatents

Grushkowitz, Tyler; Fischer, Kevin; Danning, Matthew

2016-09-20

A wire management device is disclosed. The device comprises a clip comprising an upper planar member and a lower planar member, each planar member having an inner and outer surface, wherein the inner surface of the upper planar member includes a post extending toward the inner surface of the lower planar member, a stem extending from the outer surface of the lower planar member, the stem including two outwardly-extending flanges, each of the first and second outwardly-extending flanges including an edge portion extending toward the outer surface of the lower planar member, and a transverse passage extending along the outer surface of the lower planar member, the transverse passage extending across the stem, wherein the stem has a recessed portion along the transverse passage.

Shear Lag in Box Beams Methods of Analysis and Experimental Investigations

NASA Technical Reports Server (NTRS)

Kuhn, Paul; Chiarito, Patrick T

1942-01-01

The bending stresses in the covers of box beams or wide-flange beams differ appreciably from the stresses predicted by the ordinary bending theory on account of shear deformation of the flanges. The problem of predicting these differences has become known as the shear-lag problem. The first part of this paper deals with methods of shear-lag analysis suitable for practical use. The second part of the paper describes strain-gage tests made by the NACA to verify the theory. Three tests published by other investigators are also analyzed by the proposed method. The third part of the paper gives numerical examples illustrating the methods of analysis. An appendix gives comparisons with other methods, particularly with the method of Ebner and Koller.

Structural Oil Pan With Integrated Oil Filtration And Cooling System

DOEpatents

Freese, V, Charles Edwin

2000-05-09

An oil pan for an internal combustion engine includes a body defining a reservoir for collecting engine coolant. The reservoir has a bottom and side walls extending upwardly from the bottom to present a flanged lip through which the oil pan may be mounted to the engine. An oil cooler assembly is housed within the body of the oil pan for cooling lubricant received from the engine. The body includes an oil inlet passage formed integrally therewith for receiving lubricant from the engine and delivering lubricant to the oil cooler. In addition, the body also includes an oil pick up passage formed integrally therewith for providing fluid communication between the reservoir and the engine through the flanged lip.

[Factors affecting residual stones after percutaneous nephrolithotomy in patients with renal calculus].

PubMed

Qiao, Mingzhou; Zhang, Haifang; Zhou, Chenlong

2015-11-24

To explore the factors affecting the residual stones after percutaneous nephrolithotomy (PCNL) in patients with renal calculus. A retrospective analysis was performed for 1 200 patients who were affected by renal calculus and treated with PCNL between Jan 2008 and May 2014 in People's Hospital of Anyang City. Among those patients, 16 were diagnosed as bilateral renal stone and had two successive operations. The size, location and number of stones, previous history of surgery, the degree of hydronephrosis, urinary infection were included in the univariate analysis. Significant factors in univariate analysis were included in the multivariate analysis to determine factors affecting stone residual. A total of 385 cases developed stone residual after surgery. The overall residual rate was 31.7%. In univariate analysis, renal pelvis combined with caliceal calculus (P=0.006), stone size larger than 4 cm (P=0.005), stone number more than 4 (P=0.002), the amount of bleeding more than 200 ml (P=0.025), operation time longer than 120 minutes (P=0.028) were associated with an increased rate of stone residual. When subjected to the Cox multivariate analysis, the independent risk factors for residual stones were renal pelvis combined with caliceal calculus (P=0.049), stone size larger than 4 cm (P=0.038) and stone number more than 4 (P=0.018). Factors affecting the incidence of residual stones after PCNL are the size, location and number of stones. Larger size stone and the presence of renal pelvis combined with caliceal calculus are significantly associated with residual stones. Nevertheless, stone number less than 4 indicates an increased stone clearance rate.

Significance of lower-pole pelvicaliceal anatomy on stone clearance after shockwave lithotripsy in nonobstructive isolated renal pelvic stones.

PubMed

Sozen, Sinan; Kupeli, Bora; Acar, Cenk; Gurocak, Serhat; Karaoglan, Ustunol; Bozkirli, Ibrahim

2008-05-01

To investigate the probable effect of lower-pole pelvicaliceal anatomy on stone clearance after shockwave lithotripsy (SWL) in patients with nonobstructive renal pelvic stones. The clinical records of patients with isolated renal pelvic stones who underwent SWL between 1996 and 2005 were reviewed. After excluding patients with obstruction leading to dilatation, major anatomic abnormalities, noncalcium stones, metabolic abnormalities, history of recurrent stone disease, multiple stones, and previous renal surgery, 153 patients were enrolled in the study. Lower pole infundibulopelvic angle (IPA) and infundibular length and width were measured from intravenous urography. Patients were classified into three groups according to stone burden (group 1, <100 mm(2); group 2, 101-200 mm(2); group 3, 201-400 mm(2)). The mean stone size was 142.08+/-86.3 mm(2). Overall stone-free rate was 53.6%. Localization of clinically significant or insignificant residual fragments was in the lower calix, renal pelvis, and both in 50 (32.6%), 29 (18.9%), and 8 (5.2%) patients, respectively. There was no statistically significant difference in pelvicaliceal anatomic features except narrower IPA (P=0.02) in group 1 patients with residual stones. The falling of stone fragments to the lower calix in spite of the ureter whether clinically significant or not after SWL of pelvic stones initially seems to be related to stone burden rather than lower caliceal anatomy. However, existence of a more narrow IPA in group 1 patients with residual fragments led us to believe that lower-pole IPA can play a role in stone clearance, especially for smaller stones, probably because of smaller residual fragment size or the more mobile nature of the primary stone.

In Idiopathic Calcium Oxalate Stone Formers, Unattached Stones Show Evidence of Having Originated as Attached Stones on Randall’s Plaque

PubMed Central

Miller, Nicole L.; Williams, James C.; Evan, Andrew P.; Bledsoe, Sharon B.; Coe, Fredric L.; Worcester, Elaine M.; Munch, Larry C.; Handa, Shelly E.; Lingeman, James E.

2009-01-01

Objective To analyze the structure and composition of unattached stones in idiopathic calcium oxalate stone formers (ICSF) and compare them to attached stones from the same cohort in order to investigate whether more than one pathogenic mechanism exists for stone formation in ICSF. Patients and methods ICSF undergoing percutaneous nephrolithotomy or ureteroscopy for treatment of nephrolithiasis were consented for this study. All accessible renal papillae were endoscopically imaged using a digital endoscope. All stones were removed and determined by the operating surgeon to be attached or unattached to the underlying papilla. Micro-computed tomography (micro-CT), which provides three-dimensional analysis of entire stones, was used to compare the structure and composition of attached versus unattached stones. Results Of 115 stones collected from 9 patients (12 renal units), only 25 stones were found not to be attached to renal papillae. Of these 25 stones, 4 were lost and 12 showed definite morphological evidence of having been attached to tissue, probably having been knocked off of papillae during access. For the remaining 9 stones, micro-CT analysis revealed at least one internal region of calcium phosphate within each of these unattached calcium oxalate (CaOx) stones. That is, the internal structure of the unattached stones is consistent with their having originated attached to RP, and then having become detached but retained in the kidney, with new layers of CaOx eventually covering the original attachment site. Conclusions Micro CT analysis supports the hypothesis that in ICSF, both attached and unattached stones occur as a result of a common pathogenic mechanism. That is, in this type of stone former, CaOx stones—even those not showing morphology that betrays attachment—all originate attached to interstitial plaque on the renal papilla. PMID:19549258

Combined Burst Wave Lithotripsy and Ultrasonic Propulsion for Improved Urinary Stone Fragmentation.

PubMed

Zwaschka, Theresa A; Ahn, Justin S; Cunitz, Bryan W; Bailey, Michael R; Dunmire, Barbrina; Sorensen, Mathew D; Harper, Jonathan D; Maxwell, Adam D

2018-04-01

Burst wave lithotripsy (BWL) is a new technology in development to fragment urinary stones. Ultrasonic propulsion (UP) is a separate technology under investigation for displacing stones. We measure the effect of propulsion pulses on stone fragmentation from BWL. Two artificial stone models (crystalline calcite, BegoStone plaster) and human calcium oxalate monohydrate (COM) stones measuring 5 to 8 mm were subjected to ultrasound exposures in a polyvinyl chloride tissue phantom within a water bath. Stones were exposed to BWL with and without propulsion pulses interleaved for set time intervals depending on stone type. Fragmentation was measured as a fraction of the initial stone mass fragmented to pieces smaller than 2 mm. BegoStone model comminution improved from 6% to 35% (p < 0.001) between BWL and BWL with interleaved propulsion in a 10-minute exposure. Propulsion alone did not fragment stones, whereas addition of propulsion after BWL slightly improved BegoStone model comminution from 6% to 11% (p < 0.001). BegoStone model fragmentation increased with rate of propulsion pulses. Calcite stone fragmentation improved from 24% to 39% in 5 minutes (p = 0.047) and COM stones improved from 17% to 36% (p = 0.01) with interleaved propulsion. BWL with UP improved stone fragmentation compared with BWL alone in vitro. The improvement was greatest when propulsion pulses are interleaved with BWL treatment and when propulsion pulses are applied at a higher rate. Thus, UP may be a useful adjunct to enhance fragmentation in lithotripsy in vivo.

Black and brown pigment gallstones differ in microstructure and microcomposition.

PubMed

Malet, P F; Takabayashi, A; Trotman, B W; Soloway, R D; Weston, N E

1984-01-01

The two subtypes of pigment gallstones, black and brown stones, differ in chemical composition and pathogenesis. We examined a black bilirubinate stone and a black phosphate stone (which represented opposite ends of the compositional spectrum of black noncarbonate stones), a black carbonate stone, and a brown pigment stone using scanning electron microscopy and microchemical techniques to determine if stone microstructure and microcomposition reflected different patterns of formation. The cross-sectional surfaces of the black bilirubinate and black phosphate stones were smooth and homogenous. Electron probe microanalysis demonstrated high concentrations of sulfur and copper in the center of the black bilirubinate stone; sulfur was in a low valence state consistent with disulfide linkages in proteins. The brown stone was rough-surfaced with lamellated bands on cross-section. The lighter-colored bands in this stone contained virtually all of the detected calcium palmitate, while the darker sections contained much more calcium bilirubinate. Plasma oxygen etching demonstrated a network of protein interdigitating with calcium bilirubinate salts in the black bilirubinate and black phosphate stones but not in the black carbonate or brown stones. Argon ion etching demonstrated that calcium bilirubinate was in a closely packed rod-shaped arrangement in all three black stones but not in the brown stone. We conclude that the marked differences in structure and composition between the black noncarbonate and brown pigment gallstones support the hypothesis that the two major pigment gallstone types form by different mechanisms. In addition, the layered structures of the black carbonate and brown stones suggest that stone growth is affected by cyclic changes in biliary composition.

Is retrograde intrarenal surgery the game changer in the management of upper tract calculi? A single-center single-surgeon experience of 131 cases.

PubMed

Parikh, Kandarp Priyakant; Jain, Ravi Jineshkumar; Kandarp, Aditya Parikh

2018-01-01

Success of any modality for stone disease needs to be evaluated in terms of Stone Free Rates (SFR), auxiliary procedures needed; complications and follow up. SFR in RIRS is subject to parameters like stone burden, location, number, hardness, composition; calyceal and ureter anatomy; use of ureteric access sheath (UAS); surgeon experience etc. The aim of this study is to evaluate the efficacy and safety of RIRS for managing upper tract stones. The objectives include evaluating SFR in RIRS in relation to stone burden, location and number. Other objectives include evaluating SFR after re RIRS in relation to stone burden, necessity of pre DJ stenting, use of UAS and post operative complication rate. 131 patients operated by single surgeon for single/multiple renal and/or upper ureteric stones were evaluated. Stone size > 3 mm on follow up CT KUB was considered as residual. Re RIRS was required for residual stones. The overall SFR was 76%. SFR were statistically lower with stone burden > 1.5 cm, lower calyceal stones and single stones with stone burden > 1.5 cm. SFR was 90% after 2 nd RIRS and 98.5% after 3 rd RIRS procedure. No significant difference in SFR was noted between single v/s multiple stones, single calyx v/s multiple calyx stones and renal v/s upper ureteric stones. No major complication was noted. Larger stone burden and lower calyceal location are important factors deciding SFR in RIRS. With auxiliary procedure, RIRS is safe and effective compared to PCNL.

Impact of stone density on outcomes in percutaneous nephrolithotomy (PCNL): an analysis of the clinical research office of the endourological society (CROES) pcnl global study database.

PubMed

Anastasiadis, Anastasios; Onal, Bulent; Modi, Pranjal; Turna, Burak; Duvdevani, Mordechai; Timoney, Anthony; Wolf, J Stuart; De La Rosette, Jean

2013-12-01

This study aimed to explore the relationship between stone density and outcomes of percutaneous nephrolithotomy (PCNL) using the Clinical Research Office of the Endourological Society (CROES) PCNL Global Study database. Patients undergoing PCNL treatment were assigned to a low stone density [LSD, ≤ 1000 Hounsfield units (HU)] or high stone density (HSD, > 1000 HU) group based on the radiological density of the primary renal stone. Preoperative characteristics and outcomes were compared in the two groups. Retreatment for residual stones was more frequent in the LSD group. The overall stone-free rate achieved was higher in the HSD group (79.3% vs 74.8%, p = 0.113). By univariate regression analysis, the probability of achieving a stone-free outcome peaked at approximately 1250 HU. Below or above this density resulted in lower treatment success, particularly at very low HU values. With increasing radiological stone density, operating time decreased to a minimum at approximately 1000 HU, then increased with further increase in stone density. Multivariate non-linear regression analysis showed a similar relationship between the probability of a stone-free outcome and stone density. Higher treatment success rates were found with low stone burden, pelvic stone location and use of pneumatic lithotripsy. Very low and high stone densities are associated with lower rates of treatment success and longer operating time in PCNL. Preoperative assessment of stone density may help in the selection of treatment modality for patients with renal stones.

Histopathology Predicts the Mechanism of Stone Formation

NASA Astrophysics Data System (ADS)

Evan, Andrew P.

2007-04-01

About 5% of American women and 12% of men will develop a kidney stone at some time in their life and these numbers appear to be on the rise. Despite years of scientific research into the mechanisms of stone formation and growth, limited advances have been made until recently. Randall's original observations and thoughts on the mechanisms for kidney stone formation have been validated for idiopathic calcium oxalate stone formers (ICSF) but not for most other stone forming groups. Our current studies on selected groups of human stone formers using intraoperative papillary biopsies has shown overwhelming evidence for the presence of Randall's plaque in ICSF and that stone formation and growth are exclusively linked to its availability to urinary ions and proteins. Intense investigation of the plaque-stone junction is needed if we are to understand the factors leading to the overgrowth process on exposed regions of plaque. Such information should allow the development of treatment strategies to block stone formation in ICSF patients. Patients who form brushite stones, or who form apatite stones because of distal renal tubular acidosis (dRTA), or patients with calcium oxalate stones due to obesity bypass procedures, or patients with cystinuria, get plugged inner medullary collecting ducts (IMCD) which leads to total destruction of the lining cells and focal sites of interstitial fibrosis. These stone formers have plaque but at levels equal to or below non-stone formers, which would suggest that they form stones by a different mechanism than do ICSF patients.

Open stone surgery: a still-in-use approach for complex stone burden.

PubMed

Çakici, Özer Ural; Ener, Kemal; Keske, Murat; Altinova, Serkan; Canda, Abdullah Erdem; Aldemir, Mustafa; Ardicoglu, Arslan

2017-06-30

Urinary stone disease is a major urological condition. Endourologic techniques have influenced the clinical approach and outcomes. Open surgery holds a historic importance in the management of most conditions. However, complex kidney stone burden may be amenable to successful results with open stone surgery. In this article, we report our eighteen cases of complex urinary stone disease who underwent open stone removal. A total of 1701 patients have undergone surgical treatment for urinary stone disease in our clinic between July 2012 and July 2016, comprising eighteen patients who underwent open stone surgery. Patients' demographic data, stone analysis results, postoperative clinical data, and stone status were evaluated retrospectively. The choice of surgical approach is mostly dependent on the surgeon's preference. In two patients, open surgery was undertaken because of perioperative complications. We did not observe any Clavien-Dindo grade 4 or 5 complications. Three patients were managed with a course of antibiotics due to postoperative fever. One patient had postoperative pleurisy, one patient had urinoma, and two patients had postoperative ileus. Mean operation time was 84 (57-124) minutes and mean hospitalization time was 5.5 (3-8) days. Stone-free status was achieved in 15 patients (83.3%). Endourologic approaches are the first options for treatment of urinary stone disease. However, open stone surgery holds its indispensable position in complicated cases and in complex stone burden. Open stone surgery is also a valid alternative to endourologic techniques in all situations.

[Infrared spectrophotometry for crystalline composition of staghorn calculi].

PubMed

Ma, Kai; Huang, Xiao-bo; Xu, Qing-quan; Li, Jian-xing; Xiong, Liu-lin; Yang, Bo; Ye, Xiong-jun; Chen, Liang; Wang, Xiao-feng; Na, Yan-qun

2010-11-30

To provide theoretic rationales for treatment and prevention of staghorn calculi by analyzing stone composition and studying the relationship between stone and urinary tract infections. The clinical data of 51 staghorn calculi patients were analyzed retrospectively. The stone compositions were studied by infrared spectrophotometry. Six types of stone compositions were obtained. There were calcium oxalate monohydrate, calcium oxalate dehydrate, carbonate apatite, magnesium ammonium phosphate hexahydrate, uric acid and L-cystine. The majority of stones were of mixed compositions, pure stones were found in 15 cases (29.4%). Among all stones, calcium oxalate stones were found in 41 cases (80.4%) and uric stones in 10 cases (19.6%). Infectious stones were found in 26 cases (51.0%). Urinary tract infections were found in 40 (78.4%) patients and positive urine/stone culture was detected in 33 (64.7%) patients. With multiple crystalline compositions and etiological factors, the staghorn calculi are closely correlated with urinary tract infections.

Salivary stones: symptoms, aetiology, biochemical composition and treatment.

PubMed

Kraaij, S; Karagozoglu, K H; Forouzanfar, T; Veerman, E C I; Brand, H S

2014-12-05

Salivary stones, also known as sialoliths, are calcified concrements in the salivary glands. Sialoliths are more frequently located in the submandibular gland (84%), than in the parotid gland (13%). The majority of the submandibular stones are located in Wharton's duct (90%), whereas parotid stones are more often located in the gland itself. Salivary stones consist of an amorphous mineralised nucleus, surrounded by concentric laminated layers of organic and inorganic substances. The organic components of salivary stones include collagen, glycoproteins, amino acids and carbohydrates. The major inorganic components are hydroxyapatite, carbonate apatite, whitlockite and brushite. The management of salivary stones is focused on removing the salivary stones and preservation of salivary gland function which depends on the size and location of the stone. Conservative management of salivary stones consists of salivary gland massage and the use of sialogogues. Other therapeutic options include removal of the stone or in some cases surgical removal of the whole salivary gland.

Single-session ureteroscopic pneumatic lithotripsy for the management of bilateral ureteric stones.

PubMed

Isen, Kenan

2012-01-01

In nowadays there is no consensus on single-session ureteroscopic lithotripsy (URSL) for the management of bilateral ureteric stones. The aim of this study was to evaluate efficacy and safety of single-session URSL in patients with bilateral ureteric stones. 41 patients who have undergone bilateral single-session URSL were evaluted in this study. A 8/9.8 Fr Wolf semi-rigid ureteroscope was used for the procedures, and the stones were fragmented with pneumatic lithotripter. A high stone-free rate was achieved (90.2%) after single endoscopic procedure with a retreatment rate of 9.8%. The procedure was most successful for distal ureteric stones with a 96.2% stone-free rate followed by middle ureteric stones with a 81.8% stone-free rate while the least success was achieved for proximal ureteric stones with a 77.7% stone-free rate (p < 0.05). A greater stone-free rate was obtained in those with stones less than 10 mm (93.7%) than in those with stones larger than 10 mm (77.7%) (p < 0.05). Ureteral perforation occurred in only one patient (2.4%). No long-term complication was observed in any patient. Bilateral single-session URSL can be performed effectively and safely with a low complication rate in patients with bilateral ureteric stones. It can reduce the need of anaesthetics and hospital stay.

Using Helical CT to Predict Stone Fragility in Shock Wave Lithotripsy (SWL)

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

Williams, James C. Jr.; Zarse, Chad A.; Jackson, Molly E.

2007-04-05

Great variability exists in the response of urinary stones to SWL, and this is true even for stones composed of the same mineral. Efforts have been made to predict stone fragility to shock waves using computed tomography (CT) patient images, but most work to date has focused on the use of stone CT number (i.e., Hounsfield units). This is an easy number to measure on a patient stone, but its value depends on a number of factors, including the relationship of the size of the stone to me resolution (i.e., the slicewidth) of the CT scan. Studies that have shownmore » a relationship between stone CT number and failure in SWL are reviewed, and all are shown to suffer from error due to stone size, which was not accounted for in the use of Hounsfield unit values. Preliminary data are then presented for a study of calcium oxalate monohydrate (COM) stones, in which stone structure-rather than simple CT number values-is shown to correlate with fragility to shock waves. COM stones that were observed to have structure by micro CT (e.g., voids, apatite regions, unusual shapes) broke to completion in about half the number of shock waves required for COM stones that were observed to be homogeneous in structure by CT. This result suggests another direction for the use of CT in predicting success of SWL: the use of CT to view stone structure, rather than simply measuring stone CT number. Viewing stone structure by CT requires the use of different viewing windows than those typically used for examining patient scans, but much research to date indicates that stone structure can be observed in the clinical setting. Future clinical studies will need to be done to verify the relationship between stone structure observed by CT and stone fragility in SWL.« less

Characteristics of renal papillae in kidney stone formers.

PubMed

Marien, Tracy P; Miller, Nicole L

2016-12-01

The mechanism of kidney stone formation is not well understood. In order to better understand the pathophysiology for specific kidney stone compositions and systemic diseases associated with kidney stones, endoscopic papillary mapping studies with concurrent biopsies have been conducted. This review will summarize the findings of these studies and proposed mechanisms for thirteen disease processes associated with kidney stones. A review of the literature was performed identifying thirteen studies that endoscopically mapped and biopsied renal papillae of different stone formers. These studies characterized renal papillae based on amount of Randall's plaque, Bellini's duct pathology, papillary contour changes, presence of attached stones, pitting, and frequently papillary and cortical biopsies. The groups studied and reviewed here are kidney stone formers who have a history of idiopathic calcium oxalate stone formation, cystinuria, brushite stones, gastric bypass, ileostomy, small bowel resection, primary hyperparathyroidism, distal renal tubular acidosis (dRTA), primary hyperoxaluria, idiopathic calcium phosphate stone formation, medullary sponge kidney (MSK), uric acid stones, and struvite stones. A proposed standardized scoring system for papillary pathology was also reviewed. The series showed various degrees and types of changes to the renal papillae and corresponding histopathologic changes for each type of stone former reviewed. Those with predominantly alone Randall's plaque pathology had less tissue damage versus those with extensive Bellini's duct lesions who had more interstitial fibrosis and cortical pathology. Randall's plaques are associated with stone formers who have low urinary volume, high urinary calcium, and acidic urine and thus are frequently seen in those with brushite stones, primary hyperparathyroidism, small bowel resection, and idiopathic calcium phosphate stone formers. Bellini's duct plugging and pathology is theorized to occur via free solution crystallization, ductal obstruction, inflammation, cellular injury, fibrosis, and acidification defects. Ureteroscopic manifestations of stone disease can vary from normal appearing papillae to significantly diseased appearing papillae. Some diseases have very characteristic papillary changes. Further studies are necessary to fully elucidate the mechanisms of stone formation in patients with nephrolithiasis.

Advances in lithotripsy and stone disease treatment.

PubMed

Newman, J

1996-01-01

Stone disease can be traced back as far as the human record. This article traces the diagnosis and treatment of stone disease from primitive attempts at stone removal in ancient civilizations to the advent of extracorporeal shock wave lithotripsy (ESWL) in the 1970s. ESWL revolutionized the treatment of stone disease, offering patients a less painful alternative to the traditional surgical removal of stones. This article discusses recent advances in ESWL, describes the radiologic technologist's role in diagnosing and managing stone disease, and outlines future prospects in the treatment of stone disease.

Infection (urease) stones.

PubMed

Griffith, D P; Osborne, C A

1987-01-01

Infection-induced stones in man probably form solely as a consequence of urealysis which is catalyzed by the bacterial protein urease. Urease stones composed of struvite and carbonate-apatite may form primarily, or as secondary stones or pre-existent metabolic stones. Struvite stones form and grow rapidly owing to (a) supersaturation of urine with stone forming salts, (b) 'salting out' of poorly soluble organic substances normally dissolved in urine and (c) ammonia-induced destruction of the normally protective urothelial glycosaminoglycan layer. Immature (predominantly organic) matrix stones mature into densely mineralized stones. Curative treatment is possible only by eliminating all of the stone and by eradicating all urinary and parenchymal infection. A variety of operative and pharmaceutical approaches are available. Patient treatment must be individualized inasmuch as some patients are better candidates for one type of treatment than another.

Risk factors for recurrent symptomatic pigmented biliary stones after percutaneous transhepatic biliary extraction.

PubMed

Kim, Dong Won; Lee, Sang Yun; Cho, Jin-Han; Kang, Myong Jin; Noh, Myung Hwan; Park, Byeong-Ho

2010-07-01

To evaluate risk factors for the recurrence of biliary stones after a percutaneous transhepatic biliary stone extraction. The procedures were performed on 339 patients between July 2004 and December 2008 (54 months). Medical records and images were retrospectively reviewed for 135 patients (mean age, 66.4 years; 83 men and 52 women) who had undergone follow-up for a mean of 13.2 months (range, 3-37 months). To evaluate risk factors for the recurrence of biliary stones, variables were evaluated with univariate and multivariate analyses. Variables included sex, age, stone location, number of stones, stone size, presence of a peripapillary diverticulum, application of antegrade sphincteroplasty, presence of a biliary stricture, largest biliary diameter before the procedure, and gallbladder status. Thirty-three of the 135 patients (24%) had recurrent symptomatic biliary stones and underwent an additional extraction. The mean time to recurrence was 17.2 months +/- 8.7. Univariate analysis of risk factors for recurrence of biliary stones demonstrated that location, number of stones, stone size, application of antegrade sphincteroplasty, presence of a biliary stricture, and biliary diameter were significant factors (P < .05). With use of multivariate analysis, the number of stones (> or =6; relative risk, 64.8; 95% confidence interval: 5.8, 717.6) and stone size (> or =14 mm; relative risk, 3.8; 95% confidence interval: 1.138, 13.231) were determined to be significant risk factors. The independent risk factors for recurrence of symptomatic biliary stones after percutaneous transhepatic biliary stone extraction were a stone size of at least 14 mm and the presence of at least six stones. Copyright 2010 SIR. Published by Elsevier Inc. All rights reserved.

Stone clearance after extracorporeal shockwave lithotripsy in patients with solitary pure calcium oxalate stones smaller than 1.0 cm in the proximal ureter, with special reference to monohydrate and dihydrate content.

PubMed

Ichiyanagi, Osamu; Nagaoka, Akira; Izumi, Takuji; Kawamura, Yuko; Tsukigi, Masaaki; Ishii, Tatsuya; Ohji, Hiroshi; Kato, Tomoyuki; Tomita, Yoshihiko

2013-04-01

The aim of this study was to assess stone-free rates following extracorporeal shockwave lithotripsy (ESWL) of pure calcium oxalate (CaOx) stones in the proximal ureter. The investigators retrospectively examined 53 patients with 5-10 mm pure CaOx stones in the proximal ureter from the medical archives of 593 consecutive patients treated with ESWL. The compositions of calcium oxalate monohydrate (COM) and dihydrate (COD) in a given stone were determined by infrared spectrometry. Stone size, attenuation number and stone-to-skin distance (SSD) were measured using plain radiography and computed tomography (CT). ESWL success was evaluated by stone-free status after the first single session. On average, calculi were 8.0 × 5.3 mm in size, with an SSD of 11.0 cm. The mean CT attenuation value was 740.1 HU. Attenuation numbers correlated significantly with stone diameter (r = 0.49), but had no correlation with the stone content of COM or COD. A negative correlation was observed between COM and COD content (r = -0.925). With regard to patients' physical characteristics and COM and COD content, no differences were found between study subgroups with stone-free and residual status (n = 38 and 15, respectively). There were also no differences in clinical features between patient subgroups with COM- or COD-predominant stones (n = 22 and 31, respectively). The findings indicated that the differences in COM and COD content of CaOx stones had no impact on stone clearance after ESWL and that a favorable stone-free rate of the stones treated with ESWL may be achieved independently of CaOx hydration.

Combined retrograde flexible ureteroscopic lithotripsy with holmium YAG laser for renal calculi associated with ipsilateral ureteral stones.

PubMed

Cocuzza, Marcello; Colombo, Jose R; Ganpule, Arvind; Turna, Burak; Cocuzza, Antonio; Dhawan, Divyar; Santos, Bruno; Mazzucchi, Eduardo; Srougi, Miguel; Desai, Mahesh; Desai, Mihir

2009-02-01

The purpose of this study was to evaluate the effectiveness of combined ureteroscopic holmium YAG lithotripsy for renal calculi associated with ipsilateral ureteral stones. Between August 2002 and March 2007, retrograde flexible ureteroscopic stone treatment was attempted in 351 cases. Indication for treatment was concurrent symptomatic ureteral stones in 63 patients (group I). Additional operative time and perioperative complication rates were compared to a group of 39 patients submitted to ureteroscopic treatment for ureteral calculi exclusively (group II). Mean ureteral stone size was 8.0 +/- 2.6 mm and 8.1 +/- 3.4 mm for groups I and II, respectively. Mean operative time for group I was 67.9 +/- 29.5 minutes and for group 2 was 49.3 +/- 13.2 minutes (p < 0.001). Flexible ureteroscopic therapy for renal calculi increased 18 minutes in the mean operative time. The overall complication rate was 3.1% and 2.5% for groups I and II, respectively (p = 0.87). Mean renal stone size was 10.7 +/- 6.4 mm, overall stone free rate in group I was 81%. However, considering only patients with renal stones smaller than 15 mm, the stone free rate was 88%. Successful treatment occurred in 81% of patients presenting lower pole stones, but only 76% of patients with multiple renal stones became stone free. As expected, stone free rate showed a significant negative correlation with renal stone size (p = 0.03; r = -0.36). Logistic regression model indicated an independent association of renal stones smaller than 15 mm and stone free rate (OR = 13.5; p = 0.01). Combined ureteroscopic treatment for ureteral and ipsilateral renal calculi is a safe and attractive option for patients presenting for symptomatic ureteral stone and ipsilateral renal calculi smaller than 15 mm.

Stone-Mode Ultrasound for Determining Renal Stone Size.

PubMed

May, Philip C; Haider, Yasser; Dunmire, Barbrina; Cunitz, Bryan W; Thiel, Jeff; Liu, Ziyue; Bruce, Matthew; Bailey, Michael R; Sorensen, Mathew D; Harper, Jonathan D

2016-09-01

The purpose of this study was to measure the accuracy of stone-specific algorithms (S-mode) and the posterior acoustic shadow for determining kidney stone size with ultrasound (US) in vivo. Thirty-four subjects with 115 renal stones were prospectively recruited and scanned with S-mode on a research US system. S-mode is gray-scale US adjusted to enhanced stone contrast and resolution by minimizing compression and averaging, and increasing line density and frequency. Stone and shadow width were compared with a recent CT scan and, in 5 subjects with 18 stones, S-mode was compared with a clinical US system. Overall, 84% of stones identified on CT were detected on S-mode and 66% of these shadowed. Seventy-three percent of the stone measurements and 85% of the shadow measurements were within 2 mm of the size on CT. A posterior acoustic shadow was present in 89% of stones over 5 mm versus 53% of stones under 5 mm. S-mode visualized 78% of stones, versus 61% for the clinical system. S-mode stone and shadow measurements differed from CT by 1.6 ± 1.0 mm and 0.8 ± 0.6 mm, respectively, compared with 2.0 ± 1.5 mm and 1.6 ± 1.0 mm for the clinical system. S-mode offers improved visualization and sizing of renal stones. With S-mode, sizing of the stone itself and the posterior acoustic shadow were similarly accurate. Stones that do not shadow are most likely <5 mm and small enough to pass spontaneously.

Natural history of asymptomatic renal stones and prediction of stone related events.

PubMed

Kang, Ho Won; Lee, Sang Keun; Kim, Won Tae; Kim, Yong-June; Yun, Seok-Joong; Lee, Sang-Cheol; Kim, Wun-Jae

2013-05-01

The appropriate management for asymptomatic renal stones remains unclear. We assessed the natural history and progression rate of such stones and identified clinical factors associated with an increased risk of stone related events. We retrospectively reviewed the medical records of 201 male and 146 female patients with asymptomatic renal stones. It was recommended that patients be followed every 6 months. Mean followup was 31 months (range 6 to 180). Patients were divided into 2 groups by stone related events, including spontaneous stone passage, flank pain, stone growth or the need for intervention during followup. Spontaneous passage occurred in 101 patients (29.1%). Of the patients 186 (53.6%) and 161 (46.4%) did and did not have stone related events, respectively. Of the whole cohort 85 patients (24.5%) required intervention but only 4.6% needed surgery. At 19 months after diagnosis 50% of the patients had a symptom. Those with stone related events were more likely to be younger (mean ± SD age 46.6 ± 12.7 vs 49.3 ± 12.6 years) and male, and have a stone history (p = 0.047, 0.017 and 0.014, respectively). Male gender significantly decreased the probability of freedom from stone related events (log rank test p = 0.0135) and it was an independent predictor of stone related events (HR 1.521, p = 0.009). Younger patients, and those with smaller stones and no stone growth were more likely to experience spontaneous passage and less likely to undergo intervention (each p <0.05). Asymptomatic renal stones can be followed safely but long-term followup is necessary. Periodic followup and early intervention should be recommended in patients with risk factors. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Shock wave lithotripsy outcomes for lower pole and non-lower pole stones from a university teaching hospital: Parallel group comparison during the same time period

PubMed Central

Geraghty, Robert; Burr, Jacob; Simmonds, Nick; Somani, Bhaskar K.

2015-01-01

Introduction: Shock wave lithotripsy (SWL) is a treatment option for all locations of renal and ureteric stones. We compared the results of SWL for lower pole renal stones with all other non-lower pole renal and ureteric stones during the same time period. Material and Methods: All SWL procedures were carried out as day case procedures by a mobile lithotripter from January 2012 to August 2013. The follow-up imaging was a combination of KUB X-ray or USS. Following SWL treatment, the stone free rate (SFR) was defined as ≤3 mm fragments. Results: A total of 148 patients with a mean age of 62 years underwent 201 procedures. Of the 201 procedures, 93 (46%) were for lower pole stones. The non-lower pole stones included upper pole (n = 36), mid pole (n = 40), renal pelvis (n = 10), PUJ (n = 8), mid ureter (n = 3), upper ureter (n = 5) and a combination of upper, middle and/or lower pole (n = 6). The mean stone size for lower pole stones (7.4 mm; range: 4-16 mm) was slightly smaller than non-lower pole stones (8 mm; range: 4-17 mm). The stone fragmentation was successful in 124 (62%) of patients. However, the SFR was statistically significantly better (P = 0.023) for non-lower pole stones 43 (40%) compared to lower pole stones 23 (25%). There were 9 (4%) minor complications and this was not significantly different in the two groups. Conclusions: Although SWL achieves a moderately high stone fragmentation rate with a low complication rate, the SFR is variable depending on the location of stone and the definition of SFR, with lower pole stones fairing significantly worse than stones in all other locations. PMID:25657543

Shock wave lithotripsy outcomes for lower pole and non-lower pole stones from a university teaching hospital: Parallel group comparison during the same time period.

PubMed

Geraghty, Robert; Burr, Jacob; Simmonds, Nick; Somani, Bhaskar K

2015-01-01

Shock wave lithotripsy (SWL) is a treatment option for all locations of renal and ureteric stones. We compared the results of SWL for lower pole renal stones with all other non-lower pole renal and ureteric stones during the same time period. All SWL procedures were carried out as day case procedures by a mobile lithotripter from January 2012 to August 2013. The follow-up imaging was a combination of KUB X-ray or USS. Following SWL treatment, the stone free rate (SFR) was defined as ≤3 mm fragments. A total of 148 patients with a mean age of 62 years underwent 201 procedures. Of the 201 procedures, 93 (46%) were for lower pole stones. The non-lower pole stones included upper pole (n = 36), mid pole (n = 40), renal pelvis (n = 10), PUJ (n = 8), mid ureter (n = 3), upper ureter (n = 5) and a combination of upper, middle and/or lower pole (n = 6). The mean stone size for lower pole stones (7.4 mm; range: 4-16 mm) was slightly smaller than non-lower pole stones (8 mm; range: 4-17 mm). The stone fragmentation was successful in 124 (62%) of patients. However, the SFR was statistically significantly better (P = 0.023) for non-lower pole stones 43 (40%) compared to lower pole stones 23 (25%). There were 9 (4%) minor complications and this was not significantly different in the two groups. Although SWL achieves a moderately high stone fragmentation rate with a low complication rate, the SFR is variable depending on the location of stone and the definition of SFR, with lower pole stones fairing significantly worse than stones in all other locations.

KIDNEY STONES: AN UPDATE ON CURRENT PHARMACOLOGICAL MANAGEMENT AND FUTURE DIRECTIONS

PubMed Central

Xu, Hongshi; Zisman, Anna L.; Coe, Fredric L.; Worcester, Elaine M.

2013-01-01

Introduction Kidney stones are a common problem worldwide with substantial morbidities and economic costs. Medical therapy reduces stone recurrence significantly. Much progress has been made in the last several decades in improving therapy of stone disease. Areas covered 1) effect of medical expulsive therapy on spontaneous stone passage, 2) pharmacotherapy in the prevention of stone recurrence, 3) future directions in the treatment of kidney stone disease. Expert Opinion fluid intake to promote urine volume of at least 2.5L each day is essential to prevent stone formation. Dietary recommendations should be adjusted based on individual metabolic abnormalities. Properly dosed thiazide treatment is the standard therapy for calcium stone formers with idiopathic hypercalciuria. Potassium alkali therapy is considered for hypocitraturia, but caution should be taken to prevent potential risk of calcium phosphate stone formation. For absorptive hyperoxaluria, low oxalate diet and increased dietary calcium intake are recommended. Pyridoxine has been shown effective in some cases of primary hyperoxaluria type I. Allopurinol is used in calcium oxalate stone formers with hyperuricosuria. Treatment of cystine stones remains challenging. Tiopronin can be used if urinary alkalinization and adequate fluid intake are insufficient. For struvite stones, complete surgical removal coupled with appropriate antibiotic therapy is necessary. PMID:23438422

Retrograde intrarenal surgery for the treatment of renal stones in children: factors influencing stone clearance and complications.

PubMed

Azili, Mujdem Nur; Ozcan, Fatma; Tiryaki, Tugrul

2014-07-01

Retrograde intrarenal surgery (RIRS) is a known option for the treatment of upper tract calculi with an excellent success. However, the reports of RIRS in prepubertal children are limited. In this study, we evaluated the factors which affected the success rate and the complications of RIRS at renal stone treatment in childhood. We retrospectively reviewed the records of children under 14 years old who underwent RIRS for renal stone disease between January 2009 and December 2012. Patients' age, gender, body mass index (BMI), stone size, stone location, stone number, intraoperative complications, stone free status, postoperative complications were recorded. There were 80 ureterorenoscopic procedures performed in 58 renal units of 47 children (23 males and 24 females). The patients' ages ranged from 8 months to 14 years (mean age 4.7 ± 3.4 years). There was a difference in the distribution of symptoms in age groups. UTI was higher in the 1-4 years age group, abdominal pain was seen mostly in children aged 5-14 years. Multiple stones (included staghorn stone) were noted in 60.4% of patients. In 27.6% of patients, ureteral stones were accompanied by renal stones in our series. In the infancy group, cystine and staghorn stones were more frequently seen, mostly bilateral. After a single ureteroscopic procedure for intrarenal stones in children, we achieved stone free status in 50.9% of the ureters (n=26). After the repeated sessions, the stone clearance rate reached to 85.1%. Retrograde intrarenal surgery can be used as a first line therapy to treat renal stones in children. This is especially important if an associated ureteral stone is present that requires treatment; or in patients with cystinuria, which is not favorably treated with ESWL. Complications were seen more frequently in patients with cystine stones. Extravasation was noted more frequently in patients admitted with UTIs. There was a significant relationship between the conversion to open procedures and the age groups, with most procedures occurring in infancy. The parents should be informed about the probability of multiple procedures to achieve stone free status. Copyright © 2014 Elsevier Inc. All rights reserved.

What happens to asymptomatic lower pole kidney stones smaller than 10 mm in children during watchful waiting?

PubMed

Telli, Onur; Hamidi, Nurullah; Bagci, Uygar; Demirbas, Arif; Hascicek, Ahmet Metin; Soygur, Tarkan; Burgu, Berk

2017-05-01

The optimal management of lower pole kidney (LPK) stones in children is controversial. The aim of this study was to determine the outcomes of children with asymptomatic isolated LPK stones smaller than 10 mm during follow-up. A total of 242 patients with 284 stones presenting at our institution between June 2004 and December 2014 with an asymptomatic, single LPK stone with a diameter of <10 mm were enrolled in the study. All children were assigned to receive first-line therapy and then categorized according to the need for medical intervention. Age, gender, stone laterality, stone size and type, associated urinary tract problems, and uncontrolled metabolic status were assessed as predictive factors of medical treatment for small (<10 mm) asymptomatic LPK stones. Stone-free rates were compared between interventions. The mean age and mean stone size were 9.4 ± 1.9 years and 7.4 ± 0.6 mm at admission, respectively. Stone progression rate was 61.2%, and the mean time for intervention was 19.2 ± 4.6 months. Flexible ureterorenoscopy (n = 68) or micro-percutaneous nephrolithotomy (n = 4) were performed for 72 stones (25.4%; group 1), and extracorporeal shock wave lithotripsy was performed for 102 stones (35.9%; group 2). The stone-free rates were 81.8 and 79.3% in group 1 and 2, respectively (p > 0.05). The remaining asymptomatic stones (110, 38.8%; group 3) were managed by continued observation, and at the end of the observation time (mean 40.8 ± 20.8 months) the spontaneous passage rate was 9.1% in this group. In the multivariate analysis, stone size of >7 mm, concurrent renal anomalies, and stones composed of magnesium ammonium phosphate (struvite) and cystine were statistically significant predictors of the need for intervention. Children with stones larger than 7 mm, renal anomalies, or stones composed of metabolically active cystine or struvite are more likely to require intervention, and those with asymptomatic LPK stones smaller than 10 mm can be managed by continued observation.

Noncontrast computed tomography can predict the outcome of shockwave lithotripsy via accurate stone measurement and abdominal fat distribution determination.

PubMed

Geng, Jiun-Hung; Tu, Hung-Pin; Shih, Paul Ming-Chen; Shen, Jung-Tsung; Jang, Mei-Yu; Wu, Wen-Jen; Li, Ching-Chia; Chou, Yii-Her; Juan, Yung-Shun

2015-01-01

Urolithiasis is a common disease of the urinary system. Extracorporeal shockwave lithotripsy (SWL) has become one of the standard treatments for renal and ureteral stones; however, the success rates range widely and failure of stone disintegration may cause additional outlay, alternative procedures, and even complications. We used the data available from noncontrast abdominal computed tomography (NCCT) to evaluate the impact of stone parameters and abdominal fat distribution on calculus-free rates following SWL. We retrospectively reviewed 328 patients who had urinary stones and had undergone SWL from August 2012 to August 2013. All of them received pre-SWL NCCT; 1 month after SWL, radiography was arranged to evaluate the condition of the fragments. These patients were classified into stone-free group and residual stone group. Unenhanced computed tomography variables, including stone attenuation, abdominal fat area, and skin-to-stone distance (SSD) were analyzed. In all, 197 (60%) were classified as stone-free and 132 (40%) as having residual stone. The mean ages were 49.35 ± 13.22 years and 55.32 ± 13.52 years, respectively. On univariate analysis, age, stone size, stone surface area, stone attenuation, SSD, total fat area (TFA), abdominal circumference, serum creatinine, and the severity of hydronephrosis revealed statistical significance between these two groups. From multivariate logistic regression analysis, the independent parameters impacting SWL outcomes were stone size, stone attenuation, TFA, and serum creatinine. [Adjusted odds ratios and (95% confidence intervals): 9.49 (3.72-24.20), 2.25 (1.22-4.14), 2.20 (1.10-4.40), and 2.89 (1.35-6.21) respectively, all p < 0.05]. In the present study, stone size, stone attenuation, TFA and serum creatinine were four independent predictors for stone-free rates after SWL. These findings suggest that pretreatment NCCT may predict the outcomes after SWL. Consequently, we can use these predictors for selecting the optimal treatment for patients with urinary stones. Copyright © 2014. Published by Elsevier Taiwan.

Factors affecting stone-free rate and complications of percutaneous nephrolithotomy for treatment of staghorn stone.

PubMed

el-Nahas, Ahmed R; Eraky, Ibrahim; Shokeir, Ahmed A; Shoma, Ahmed M; el-Assmy, Ahmed M; el-Tabey, Nasr A; Soliman, Shady; Elshal, Ahmed M; el-Kappany, Hamdy A; el-Kenawy, Mahmoud R

2012-06-01

To determine factors affecting the stone-free rate and complications of percutaneous nephrolithotomy (PNL) for treatment of staghorn stones. The computerized database of patients who underwent PNL for treatment of staghorn stones between January 2003 and January 2011 was reviewed. All perioperative complications were recorded and classified according to modified Clavien classification system. The stone-free rate was evaluated with low-dose noncontrast computed tomography (CT). Univariate and multivariate statistical analyses were performed to determine factors affecting stone-free and complication rates. The study included 241 patients (125 male and 116 female) with a mean age of 48.7 ±14.3 years. All patients underwent 251 PNL (10 patients had bilateral stones). The stone-free rate of PNL monotherapy was 56% (142 procedures). At 3 months, the stone-free rate increased to 73% (183 kidneys) after shock wave lithotripsy. Independent risk factors for residual stones were complete staghorn stone and presence of secondary calyceal stones (relative risks were 2.2 and 3.1, respectively). The complication rate was 27% (68 PNL). Independent risk factors for development of complications were performance of the procedure by urologists other than experienced endourologist and positive preoperative urine culture (relative risks were 2.2 and 2.1, respectively). Factors affecting the incidence of residual stones after PNL are complete staghorn stones and the presence of secondary calyceal stones. Complications are significantly high if PNL is not performed by an experienced endourologist or if preoperative urine culture is positive. Copyright © 2012 Elsevier Inc. All rights reserved.

Cholecystolithiasis is associated with Clonorchis sinensis infection.

PubMed

Qiao, Tie; Ma, Rui-hong; Luo, Xiao-bing; Luo, Zhen-liang; Zheng, Pei-ming

2012-01-01

The objective of this study was to analyze gallbladder stones for direct evidence of a relationship between Clonorchis sinensis infection and gallbladder stones formation. We investigated one hundred eighty-three gallbladder stones for the presence of Clonorchis sinensis eggs using microscopy, and analyzed their composition using Fourier transform infrared spectroscopy. We confirmed the presence of Clonorchis sinensis eggs in the gallbladder stones using real-time fluorescent PCR and scanning electron microscopy. Clonorchis sinensis eggs were detected in 122 of 183 gallbladder stones based on morphologic characteristics and results from real-time fluorescent PCR. The proportion of pigment stones, cholesterol stones and mixed gallstones in the egg-positive stones was 79.5% (97/122), 3.3% (4/122) and 17.2% (21/122), respectively, while 29.5% (18/61), 31.1% (19/61) and 39.3% (24/61) in the egg-negative stones. The proportion of pigment stone in the Clonorchis sinensis egg-positive stones was higher than in egg-negative stones (P<0.0001). In the 30 egg-positive stones examined by scanning electron microscopy, dozens or even hundreds of Clonorchis sinensis eggs were visible (×400) showing a distinct morphology. Many eggs were wrapped with surrounding particles, and in some, muskmelon wrinkles was seen on the surface of the eggs. Also visible were pieces of texture shed from some of the eggs. Some eggs were depressed or without operculum while most eggs were adhered to or wrapped with amorphous particles or mucoid matter (×3000). Clonorchis sinensis eggs were detected in the gallbladder stones which suggests an association between Clonorchis sinensis infection and gallbladder stones formation, especially pigment stones.

[Composition of 359 kidney stones from the East region of Algeria].

PubMed

Bouslama, S; Boutefnouchet, A; Hannache, B; Djemil, T; Kadi, A; Dahdouh, A; Saka, S; Daudon, M

2016-01-01

Determine stones composition of the upper urinary tract in the eastern region of Algeria. Our study focuses on a set of 359 stones of the upper urinary tract collected between January 2007 and December 2012 at hospitals in the eastern region of Algeria and analyzed by Fourier transform infrared spectroscopy. The male/female ratio was only 1.32. Calcium oxalate prevailed in 68.5% of stones and 49.3% of nuclei, mainly as whewellite (51.8% of stones and 37.9% of nuclei vs 16.7% and 11.4% respectively for weddellite). Carbapatite prevailed in 15% of stones and 29.8% of nuclei. The struvite, identified in 11.1% of calculi, prevailed in 3.9% of stones and 3.1% of nuclei. Among purines, uric acid prevailed with frequencies quite close to 8.9% and 7% respectively in the stone and in the nucleus while the ammonium urate prevailed in only 0.3% of stones and 3.3% of nuclei. The cystine frequency was 3.6% in both stone and nucleus. The frequency of stone with umbilication was 26.2%. Whewellite was the main component of umbilicated stones with Randall's plaque. Our results suggest that stones of the urinary tract in the Algerian east region resemble those observed in industrialized countries. Some features such as stones location, the whewellite prevalence, the frequencies of main components in both the stone and the nucleus as well as the formation of stones on renal papilla confirm this trend. 4. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

12. FLOOR 2; STONE CRANE IN PLACE FOR ROCK STONES; ...

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

12. FLOOR 2; STONE CRANE IN PLACE FOR ROCK STONES; STONE CRANE HAS OAK SPAR, JIB AND BRACE, METAL SCREW, IRON YOKE AND DOGS; IRON PINS FIT THROUGH HOLES IN DOGS INTO HOLES DRILLED IN RUNNER STONE - Hook Windmill, North Main Street at Pantigo Road, East Hampton, Suffolk County, NY

Kidney Stones (For Parents)

MedlinePlus

... Staying Safe Videos for Educators Search English Español Kidney Stones KidsHealth / For Parents / Kidney Stones What's in ... other treatments to help remove the stones. How Kidney Stones Form It's the kidneys' job to remove ...

Pediatric ureteroscopic management of intrarenal calculi.

PubMed

Tanaka, Stacy T; Makari, John H; Pope, John C; Adams, Mark C; Brock, John W; Thomas, John C

2008-11-01

Data addressing ureteroscopic management of intrarenal calculi in prepubertal children are limited. We reviewed our experience from January 2002 through December 2007. We retrospectively reviewed ureteroscopic procedures for intrarenal calculi in children younger than 14 years. Stone-free status was determined with postoperative imaging. Multiple logistic regression analysis was used to assess the influence of preoperative factors on initial stone-free status and the need for additional procedures. Intrarenal calculi were managed ureteroscopically in 52 kidneys in 50 children with a mean age of 7.9 years (range 1.2 to 13.6). Mean stone size was 8 mm (range 1 to 16). Stone-free rate after a single ureteroscopic procedure was 50% (25 of 50 patients) on initial postoperative imaging and 58% (29 of 50) with extended followup. Initial stone-free status was dependent on preoperative stone size (p = 0.005) but not stone location. Additional stone procedures were required in 18 upper tracts. Younger patient age (p = 0.04) and larger preoperative stone size (p = 0.002) were associated with the need for additional procedures. Additional procedures were required in more than half of the stones 6 mm or larger but in no stone smaller than 6 mm. Ureteroscopy is a safe method for the treatment of intrarenal calculi in the prepubertal population. Our ureteroscopic stone-free rate for intrarenal stones is lower than that reported for ureteral stones. Parents should be informed that additional procedures will likely be required, especially in younger patients and those with stones larger than 6 mm.

Urinary stone composition in Oman: with high incidence of cystinuria.

PubMed

Al-Marhoon, Mohammed S; Bayoumi, Riad; Al-Farsi, Yahya; Al-Hinai, Abdullhakeem; Al-Maskary, Sultan; Venkiteswaran, Krishna; Al-Busaidi, Qassim; Mathew, Josephkunju; Rhman, Khalid; Sharif, Omar; Aquil, Shahid; Al-Hashmi, Intisar

2015-06-01

Urinary stones are a common problem in Oman and their composition is unknown. The aim of this study is to analyze the components of urinary stones of Omani patients and use the obtained data for future studies of etiology, treatment, and prevention. Urinary stones of 255 consecutive patients were collected at the Sultan Qaboos University Hospital. Stones were analyzed by Fourier transform infrared spectrophotometer. The biochemical, metabolic, and radiological data relating to the patients and stones were collected. The mean age was 41 years, with M:F ratio of 3.7:1. The common comorbidities associated with stone formation were hypertension; diabetes, benign prostate hyperplasia; urinary tract infection; obesity; and atrophic kidney. The common presentation was renal colic and flank pain (96%). Stones were surgically retrieved in 70% of patients. Mean stone size was 9 ± 0.5 mm (range 1.3-80). Stone formers had a BMI ≥ 25 in 56% (P = 0.006) and positive family history of stones in 3.8%. The most common stones in Oman were as follows: Calcium Oxalates 45% (114/255); Mixed calcium phosphates & calcium oxalates 22% (55/255); Uric Acid 16% (40/255); and Cystine 4% (10/255). The most common urinary stones in Oman are Calcium Oxalates. Overweight is an important risk factor associated with stone formation. The hereditary Cystine stones are three times more common in Oman than what is reported in the literature that needs further genetic studies.

Laser-induced breakdown spectroscopy is a reliable method for urinary stone analysis

PubMed Central

Mutlu, Nazım; Çiftçi, Seyfettin; Gülecen, Turgay; Öztoprak, Belgin Genç; Demir, Arif

2016-01-01

Objective We compared laser-induced breakdown spectroscopy (LIBS) with the traditionally used and recommended X-ray diffraction technique (XRD) for urinary stone analysis. Material and methods In total, 65 patients with urinary calculi were enrolled in this prospective study. Stones were obtained after surgical or extracorporeal shockwave lithotripsy procedures. All stones were divided into two equal pieces. One sample was analyzed by XRD and the other by LIBS. The results were compared by the kappa (κ) and Spearman’s correlation coefficient (rho) tests. Results Using LIBS, 95 components were identified from 65 stones, while XRD identified 88 components. LIBS identified 40 stones with a single pure component, 20 stones with two different components, and 5 stones with three components. XRD demonstrated 42 stones with a single component, 22 stones with two different components, and only 1 stone with three different components. There was a strong relationship in the detection of stone types between LIBS and XRD for stones components (Spearman rho, 0.866; p<0.001). There was excellent agreement between the two techniques among 38 patients with pure stones (κ index, 0.910; Spearman rho, 0.916; p<0.001). Conclusion Our study indicates that LIBS is a valid and reliable technique for determining urinary stone composition. Moreover, it is a simple, low-cost, and nondestructive technique. LIBS can be safely used in routine daily practice if our results are supported by studies with larger numbers of patients. PMID:27011877

Direct peroral cholangioscopy using an ultraslim upper endoscope for management of residual stones after mechanical lithotripsy for retained common bile duct stones.

PubMed

Lee, Y N; Moon, J H; Choi, H J; Min, S K; Kim, H I; Lee, T H; Cho, Y D; Park, S-H; Kim, S-J

2012-09-01

The incidence of residual stones after mechanical lithotripsy for retained common bile duct (CBD) stones is relatively high. Peroral cholangioscopy using a mother-baby system may be useful for confirming complete extraction of stones, but has several limitations regarding routine use. We evaluated the role of direct peroral cholangioscopy (DPOC) using an ultraslim upper endoscope for the evaluation and removal of residual CBD stones after mechanical lithotripsy. From August 2006 to November 2010, 48 patients who had undergone mechanical lithotripsy for retained CBD stones with no evidence of filling defects in balloon cholangiography were recruited. The bile duct was inspected by DPOC after balloon cholangiography. Detected residual CBD stones were directly retrieved with a basket or balloon catheter under DPOC. The incidence of residual stones detected by DPOC, and the success rate of residual stone retrieval under DPOC were investigated. DPOC was successfully performed in 46 of the 48 patients (95.8%). Of these, 13 patients (28.3%) had residual CBD stones (mean number 1.4, range 1-3; mean diameter 4.5 mm, range 2.3-9.6). The residual stones were removed directly under DPOC in 11 of these patients (84.6%). There were no complications associated with DPOC or stone removal. DPOC using an ultraslim upper endoscope is a useful endoscopic procedure for the evaluation and extraction of residual stones after mechanical lithotripsy for retained CBD stones. © Georg Thieme Verlag KG Stuttgart · New York.

Calcium carbonate gallstones in children.

PubMed

Stringer, Mark D; Soloway, Roger D; Taylor, Donald R; Riyad, Kallingal; Toogood, Giles

2007-10-01

In the United States, cholesterol stones account for 70% to 95% of adult gallstones and black pigment stones for most of the remainder. Calcium carbonate stones are exceptionally rare. A previous analysis of a small number of pediatric gallstones from the north of England showed a remarkably high prevalence of calcium carbonate stones. The aims of this study were to analyze a much larger series of pediatric gallstones from our region and to compare their chemical composition with a series of adult gallstones from the same geographic area. A consecutive series of gallbladder stones from 63 children and 50 adults from the north of England were analyzed in detail using Fourier transform infrared microspectroscopy. Demographic and clinical data were collected on all patients. The relative proportions of each major stone component were assessed: cholesterol, protein and calcium salts of bilirubin, fatty acids, calcium carbonate, and hydroxyapatite. Thirty-nine (78%) adults had typical cholesterol stones, 7 (14%) had black pigment bilirubinate stones, and only 2 (4%) had calcium carbonate stones. In contrast, 30 (48%) children had black pigment stones, 13 (21%) had cholesterol stones, 15 (24%) had calcium carbonate stones, 3 (5%) had protein dominant stones, and 2 (3%) had brown pigment stones. In children, cholesterol stones were more likely in overweight adolescent girls with a family history of gallstones, whereas black pigment stones were equally common in boys and girls and associated with hemolysis, parenteral nutrition, and neonatal abdominal surgery. Calcium carbonate stones were more common in boys, and almost half had undergone neonatal abdominal surgery and/or required neonatal intensive care. The composition of pediatric gallstones differs significantly from that found in adults. In particular, one quarter of the children in this series had calcium carbonate stones, previously considered rare. Geographic differences are not the major reason for the high prevalence of calcium carbonate gallstones in children.

Compositional analysis of various layers of upper urinary tract stones by infrared spectroscopy

PubMed Central

He, Zhang; Jing, Zhang; Jing-Cun, Zheng; Chuan-Yi, Hu; Fei, Gao

2017-01-01

The objective of the present study was to determine the composition of various layers of upper urinary stones and assess the mechanisms of stone nucleation and aggregation. A total of 40 integrated urinary tract stones with a diameter of >0.8 cm were removed from the patients. All of the stones were cut in half perpendicularly to the longitudinal axis. Samples were selected from nuclear, internal and external layers of each stone. Fourier transform infrared spectroscopy (FT-IR) was adopted for qualitative and quantitative analysis of all of the fragments and compositional differences among nuclear, internal and external layers of various types of stone were subsequently investigated. A total of 25 cases of calcium oxalate (CaOx) stones and 10 cases of calcium phosphate (CaP) stones were identified to be mixed stones, while 5 uric acid (UA) calculi were pure stones (purity, >95%). In addition, the contents of CaOx and carbapatite (CA.AP) crystals in various layers of the mixed stones were found to be variable. In CaOx stones, the content of CA.AP in nuclear layers was significantly higher than that of the outer layers (32.0 vs. 6.8%; P<0.05), while the content of CaOx was lower in the inner than in the outer layers (57.6 vs. 86.6%; P<0.05). In CaP stones, the content of CA.AP in the nuclear layers was higher than that in the outer layers (74.0 vs. 47.3%; P<0.05), while the content of CaOx was lower in the inner than in the outer layers (7.0 vs. 40.0%; P<0.05). The UA stones showed no significant differences in their composition among different layers. In conclusion, FT-IR analysis of various layers of human upper urinary tract stones revealed that CaOx and CaP stones showed differences in composition between their core and surface, while all of the UA calculi were pure stones. The composition showed a marked variation among different layers of the stones, indicating that metabolism has an important role in different phases of the evolution of stones. The present study provided novel insight into the pathogenesis of urinary tract stones and may contribute to their prevention and treatment. PMID:28912866

Telluric currents: A meeting of theory and observation

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

Boteler, D.H.; Seager, W.H.

Pipe-to-soil (P/S) potential variations resulting from telluric currents have been observed on pipelines in many locations. However, it has never teen clear which parts of a pipeline will experience the worst effects. Two studies were conducted to answer this question. Distributed-source transmission line (DSTL) theory was applied to the problem of modeling geomagnetic induction in pipelines. This theory predicted that the largest P/S potential variations would occur at the ends of the pipeline. The theory also predicted that large P/S potential variations, of opposite sign, should occur on either side of an insulating flange. Independently, an observation program was conductedmore » to determine the change in telluric current P/S potential variations and to design counteractive measures along a pipeline in northern Canada. Observations showed that the amplitude of P/S potential fluctuations had maxima at the northern and southern ends of the pipeline. A further set of recordings around an insulating flange showed large P/S potential variations, of opposite sign, on either side of the flange. Agreement between the observations and theoretical predictions was remarkable. While the observations confirmed the theory, the theory explains how P/S potential variations are produced by telluric currents and provides the basis for design of cathodic protection systems for pipelines that can counteract any adverse telluric effects.« less

Behaviour of wrapped cold-formed steel columns under different loading conditions

NASA Astrophysics Data System (ADS)

Baabu, B. Hari; Sreenath, S.

2017-07-01

The use of Cold Formed Steel (CFS) sections as structural members is widely accepted because of its light nature. However, the load carrying capacity of these sections will be less compared to hot rolled sections. This study is meant to analyze the possibility of strengthening cold formed members by wrapping it with Glass Fiber Reinforced Polymer (GFRP) laminates. Light gauge steel columns of cross sectional dimensions 100mm x 50mm x 3.15mm were taken for this study. The effective length of the section is about 750mm. A total of 8 specimens including the control specimen is tested under axial and eccentric loading. The columns were tested keeping both ends hinged. For both loading cases the buckling behaviour, ultimate load carrying capacity and load-deflection characteristics of the CFS columns were analyzed. The GFRP laminates were wrapped on columns in three different ways such that wrapping the outer surface of web and flange throughout the length of specimen, wrapping the outer surface of web alone throughout the length of specimen and wrapping the outer surface of web and flange for the upper half length of the specimen where the buckling is expected. For both loading cases, the results indicated that the column with wrapping at the outer surface of web and flange throughout the length of specimen provides better strength for it.

Explosive actuated valve

DOEpatents

Byrne, Kenneth G.

1983-01-01

1. A device of the character described comprising the combination of a housing having an elongate bore and including a shoulder extending inwardly into said bore, a single elongate movable plunger disposed in said bore including an outwardly extending flange adjacent one end thereof overlying said shoulder, normally open conduit means having an inlet and an outlet perpendicularly piercing said housing intermediate said shoulder and said flange and including an intermediate portion intersecting and normally openly communicating with said bore at said shoulder, normally closed conduit means piercing said housing and intersecting said bore at a location spaced from said normally open conduit means, said elongate plunger including a shearing edge adjacent the other end thereof normally disposed intermediate both of said conduit means and overlying a portion of said normally closed conduit means, a deformable member carried by said plunger intermediate said flange and said shoulder and normally spaced from and overlying the intermediate portion of said normally open conduit means, and means on the housing communicating with the bore to retain an explosive actuator for moving said plunger to force the deformable member against the shoulder and extrude a portion of the deformable member out of said bore into portions of the normally open conduit means for plugging the same and to effect the opening of said normally closed conduit means by the plunger shearing edge substantially concomitantly with the plugging of the normally open conduit means.

Why do orangutans leave the trees? Terrestrial behavior among wild Bornean orangutans (Pongo pygmaeus wurmbii) at Tuanan, Central Kalimantan.

PubMed

Ashbury, Alison M; Posa, Mary Rose C; Dunkel, Lynda P; Spillmann, Brigitte; Atmoko, S Suci Utami; van Schaik, Carel P; van Noordwijk, Maria A

2015-11-01

Orangutans (genus Pongo) are the largest arboreal mammals, but Bornean orangutans (P. pygmaeus spp.) also spend time on the ground. Here, we investigate ground use among orangutans using 32,000 hr of direct focal animal observations from a well-habituated wild population of Bornean orangutans (P. p. wurmbii) living in a closed-canopy swamp forest at Tuanan, Central Kalimantan, Indonesia. Ground use did not change with increasing observation time of well-habituated individuals, suggesting it was not an artifact of observer presence. Flanged males spent the most time on the ground (ca. 5% of active time), weaned immatures the least (around 1%). Females and immatures descended mainly to feed, especially on termites, whereas flanged males traveled more while on the ground. Flanged males may travel more inconspicuously, and perhaps also faster, when moving on the ground. In addition, orangutans engaged in ground-specific behavior, including drinking from and bathing in swamp pools. Supplementary records from 20 ground-level camera traps, totaling 3986 trap days, confirmed the observed age-sex biases in ground use at Tuanan. We conclude that ground use is a natural part of the Bornean orangutan behavioral repertoire, however it remains unclear to what extent food scarcity and canopy structure explain population differences in ground use. © 2015 Wiley Periodicals, Inc.

Three-Dimensional Analysis of the Contact Pattern between the Cortical Bone and Femoral Prosthesis after Cementless Total Hip Arthroplasty

PubMed Central

Mishima, Hajime; Sugaya, Hisashi; Nishino, Tomofumi; Yamazaki, Masashi

2016-01-01

The cementless stem Excia (B. Braun, Melsungen, Germany) implant has a rectangular cross-sectional shape with back-and-forth flanges and a plasma-sprayed, dicalcium phosphate dihydrate coating from the middle to proximal portion to increase initial fixation and early bone formation. Here, the conformity of the Excia stem to the femoral canal morphology was three-dimensionally assessed using computed tomography. Forty-three patients (45 hips) were examined after primary total hip arthroplasty with a mean follow-up of 27 ± 3 months (range: 24–36 months). Spot welds occurred at zone 2 in 16 hips and at zone 6 in 24 hips, with 83% (20/24 hips) of those occurring within 3 months after surgery. First- (n = 12 hips), second- (n = 32), and third- (n = 1) degree stress shielding were observed. The stem was typically in contact with the cortical bone in the anterolateral mid-portion (100%) and posteromedial distal portions (85%). Stress shielding did not progress, even in cases where the stems were in contact with the distal portions. The anterior flange was in contact with the bone in all cases. The stability of the mid-lateral portion with the dicalcium phosphate dihydrate coating and the anterior flange may have inhibited the progression of stress shielding beyond the second degree. PMID:26881087

Surgical management of pediatric urolithiasis

PubMed Central

Mishra, Shashi K.; Ganpule, A.; Manohar, T.; Desai, Mahesh R.

2007-01-01

Pediatric urolithiasis poses a technical challenge to the urologist. A review of the recent literature on the subject was performed to highlight the various treatment modalities in the management of pediatric stones. A Medline search was used to identify manuscripts dealing with management options such as percutaneous nephrolithotomy, shock wave lithotripsy, ureteroscopy and cystolithotripsy in pediatric stone diseases. We also share our experience on the subject. Shock wave lithotripsy should be the treatment modality for renal stone less than 1cm or < 150 mm2 and proximal non-impacted ureteric stone less than 1 cm with normal renal function, no infection and favorable anatomy. Indications for PCNL in children are large burden stone more than 2cm or more than 150mm2 with or without hydronephrosis, urosepsis and renal insufficiency, more than 1cm impacted upper ureteric stone, failure of SWL and significant volume of residual stones after open surgery. Shock wave lithotripsy can be offered for more soft (< 900 HU on CT scan) renal stones between 1-2cm. Primary vesical stone more than 1cm can be tackled with percutaneous cystolithomy or open cystolithotomy. Open renal stone surgery can be done for renal stones with associated structural abnormalities, large burden infective and staghorn stones, large impacted proximal ureteric stone. The role of laparoscopic surgery for stone disease in children still needs to be explored. PMID:19718300

Analysis of the utility of stone gram stain in urolithiasis treated with percutaneous nephrolithotomy.

PubMed

Cockerill, Patrick A; Rivera, Marcelino E; Krambeck, Amy E

2014-06-01

To define the sensitivity and specificity of stone gram stain for infected urolithiasis treated with percutaneous nephrolithotomy (PCNL). PCNL procedures performed at our institution were analyzed between January 2009 and May 2013. Stone fragments were sent in a sterile fashion for aerobic and fungal cultures. A gram stain and fungal smear were performed on the stones and reported within 24 hours of collection. A total of 228 patients underwent 248 PCNLs. Of the 248 stones, 81 (33%) had a positive stone culture. Stone gram stain was positive in 31 cases and negative in 50. There were 167 negative stone cultures, and in these cases, gram stain was positive in 5 and negative in 162. The calculated sensitivity and specificity of stone gram stain were 38% and 97%. The positive and negative predictive values were 86% and 76%, respectively. In the subset of 16 patients with positive stone fungal cultures, fungal smear was performed in 12 and was positive in 4, giving fungal smear a sensitivity of 33%. The results of this study suggest that stone gram stain cannot be relied on to detect a positive stone culture and may fail to detect up to 62% of infected stones. However, when positive, gram stain accurately predicts a positive stone culture in 86% of cases. Copyright © 2014 Elsevier Inc. All rights reserved.

Treatment and prevention of kidney stones: an update.

PubMed

Frassetto, Lynda; Kohlstadt, Ingrid

2011-12-01

The incidence of nephrolithiasis (kidney stones) is rising worldwide, especially in women and with increasing age. Kidney stones are associated with chronic kidney disease. Preventing recurrence is largely specific to the type of stone (e.g., calcium oxalate, calcium phosphate, cystine, struvite [magnesium ammonium phosphate]), and uric acid stones); however, even when the stone cannot be retrieved, urine pH and 24-hour urine assessment provide information about stone-forming factors that can guide prevention. Medications, such as protease inhibitors, antibiotics, and some diuretics, increase the risk of some types of kidney stones, and patients should be counseled about the risks of using these medications. Managing diet, medication use, and nutrient intake can help prevent the formation of kidney stones. Obesity increases the risk of kidney stones. However, weight loss could undermine prevention of kidney stones if associated with a high animal protein intake, laxative abuse, rapid loss of lean tissue, or poor hydration. For prevention of calcium oxalate, cystine, and uric acid stones, urine should be alkalinized by eating a diet high in fruits and vegetables, taking supplemental or prescription citrate, or drinking alkaline mineral waters. For prevention of calcium phosphate and struvite stones, urine should be acidified; cranberry juice or betaine can lower urine pH. Antispasmodic medications, ureteroscopy, and metabolic testing are increasingly being used to augment fluid and pain medications in the acute management of kidney stones.

Development of upper tract stones in patients with congenital neurogenic bladder.

PubMed

Stephany, Heidi A; Clayton, Douglass B; Tanaka, Stacy T; Thomas, John C; Pope, John C; Brock, John W; Adams, Mark C

2014-02-01

Patients with neurogenic bladder are at increased risk of developing upper tract stones. We hypothesized that patients with lower urinary tract stone disease are at greater risk of developing upper tract stones. We performed a 10-year retrospective case-control study of patients with neurogenic bladder to determine the association between bladder and upper tract stones. Independent risk factors for upper tract stones were assessed. Cases and controls were matched 1:1. Univariable analysis was performed by Fisher's exact test and the Mann-Whitney U test. Multivariable logistic regression was performed. 52 cases and controls were identified. Cases were significantly more likely to be non-ambulatory, have bowel-urinary tract interposition, thoracic level dysraphism, and history of bladder stones. On multivariable analysis, independent predictors of stone formation were male sex (OR 2.82; p = 0.02), dysraphism involving the thoracic spine (OR 3.37; p = 0.014) bowel-urinary tract interposition (OR 2.611; p = 0.038), and a history of bladder stones (OR 3.57; p = 0.015). Patients with neurogenic bladder are at increased risk for upper tract stones. The presence of bladder stones may herald the development of upper tract stones. The predictors of stone disease identified should guide prospective studies to better understand the natural history of upper tract stone development in this population. Copyright © 2013 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

Protein content of human apatite and brushite kidney stones: significant correlation with morphologic measures.

PubMed

Pramanik, Rocky; Asplin, John R; Jackson, Molly E; Williams, James C

2008-10-01

Apatite and brushite kidney stones share calcium and phosphate as their main inorganic components. We tested the hypothesis that these stone types differ in the amount of proteins present in the stones. Intact stones were intensively analyzed by microcomputed tomography (micro CT) for both morphology (including the volume of voids, i.e., space devoid of X-ray dense material) and mineral type. To extract all proteins present in kidney stones in soluble form we developed a three-step extraction procedure using the ground stone powder. Apatite stones had significantly higher levels of total protein content and void volume compared to brushite stones. The void volume was highly correlated with the total protein contents in all stones (r2 = 0.61, P < 0.0001), and brushite stones contained significantly fewer void regions and proteins than did apatite stones (3.2 +/- 4.5% voids for brushite vs. 10.8 +/- 11.2% for apatite, P < 0.005; 4.1 +/- 1.6% protein for brushite vs. 6.0 +/- 2.4% for apatite, P < 0.03). Morphological observations other than void volume did not correlate with protein content of stones, and neither did the presence or absence of minor mineral components. Our results show that protein content of brushite and apatite stones is higher than that was previously thought, and also suggest that micro CT-visible void regions are related to the presence of protein.

Epidemiological study of urinary tract stones in a northern Italian city.

PubMed

Borghi, L; Ferretti, P P; Elia, G F; Amato, F; Melloni, E; Trapassi, M R; Novarini, A

1990-03-01

An epidemiological study of stone disease in a Northern Italian city was carried out by means of a postal questionnaire mailed to 6000 individuals (2.5% of the entire population). It was found that the incidence of stone disease was comparable to that of industrialised Western Europe. There was a relationship between stone disease and gout and stone disease and a positive family history. The frequency of uric acid stones was high (26.5%). Stone-formers showed no alimentary differences from non-stone formers apart from the use of spices and herbs. Stone-formers used less water from public aqueducts and more uncarbonated mineral water, but only 19% of these drank at least 2 litres a day.

Motion artifacts in kidney stone imaging using single-source and dual-source dual-energy CT scanners: a phantom study.

PubMed

Ibrahim, El-Sayed H; Cernigliaro, Joseph G; Pooley, Robert A; Williams, James C; Haley, William E

2015-10-01

Dual-energy computed tomography (DECT) has shown the capability of differentiating uric acid (UA) from non-UA stones with 90-100% accuracy. With the invention of dual-source (DS) scanners, both low- and high-energy images are acquired simultaneously. However, DECT can also be performed by sequential acquisition of both images on single-source (SS) scanners. The objective of this study is to investigate the effects of motion artifacts on stone classification using both SS-DECT and DS-DECT. 114 kidney stones of different types and sizes were imaged on both DS-DECT and SS-DECT scanners with tube voltages of 80 and 140 kVp with and without induced motion. Postprocessing was conducted to create material-specific images from corresponding low- and high-energy images. The dual-energy ratio (DER) and stone material were determined and compared among different scans. For the motionless scans, all stones were correctly classified with SS-DECT, while two cystine stones were misclassified with DS-DECT. When motion was induced, 94% of the stones were misclassified with SS-DECT versus 11% with DS-DECT (P < 0.0001). Stone size was not a factor in stone misclassification under motion. Stone type was not a factor in stone misclassification under motion with SS-DECT, although with DS-DECT, cystine showed higher number of stone misclassification. Motion artifacts could result in stone misclassification in DECT. This effect is more pronounced in SS-DECT versus DS-DECT, especially if stones of different types lie in close proximity to each other. Further, possible misinterpretation of the number of stones (i.e., missing one, or thinking that there are two) in DS-DECT could be a potentially significant problem.

After urgent drainage of an obstructed kidney by internal ureteric stenting; is ureteroscopic stone extraction always needed?

PubMed Central

Taha, Diaa-Eldin; Elshal, Ahmed M.; Zahran, Mohamed H.; Harraz, Ahmed M.; El-Nahas, Ahmed R.; Shokeir, Ahmed A.

2015-01-01

Objectives To assess the probability of spontaneous stone passage and its predictors after drainage of obstructed kidney by JJ stent, as insertion of an internal ureteric stent is often used for renal drainage in cases of calcular ureteric obstruction. Patients and methods Between January 2011 and June 2013, patients for whom emergent drainage by ureteric stents were identified. The patients’ demographics, presentation, and stone characteristics were reviewed. The primary endpoint for this study was stone-free status at the time of stent removal, where all patients underwent non-contrast spiral computed tomography (NCCT) before stent removal. Ureteroscopic stone extraction was performed for CT detectable ureteric stones at the time of stent removal. Potential factors affecting the need for ureteroscopic stone extraction at the time of stent removal were assessed using univariate and multivariate statistical analyses. Results Emergent ureteric stents were undertaken in 196 patients (112 males, 84 females) with a mean (SD) age of 53.7 (16.2) years, for renal obstruction drainage. At the time of stent removal, 83 patients (42.3%) were stone free; with the remaining 113 patients (57.7%) undergoing ureteroscopic stone extraction. On multivariate analysis, stone width [odds ratio (OR) 15.849, 95% confidence interval (CI) 2.83; P = 0.002) and radio-opaque stones (OR 12.035, 95% CI 4.65; P < 0.001) were independent predictors of the need for ureteroscopic stone extraction at the time of stent removal. Conclusion Spontaneous ureteric stone passage is possible after emergent drainage of an obstructed kidney by ureteric stenting. Stone opacity, larger stone width, and positive preoperative urine culture are associated with a greater probability of requiring ureteroscopic stone extraction after emergent drainage by ureteric stenting. PMID:26609444

Retrospective comparison of measured stone size and posterior acoustic shadow width in clinical ultrasound images.

PubMed

Dai, Jessica C; Dunmire, Barbrina; Sternberg, Kevan M; Liu, Ziyue; Larson, Troy; Thiel, Jeff; Chang, Helena C; Harper, Jonathan D; Bailey, Michael R; Sorensen, Mathew D

2018-05-01

Posterior acoustic shadow width has been proposed as a more accurate measure of kidney stone size compared to direct measurement of stone width on ultrasound (US). Published data in humans to date have been based on a research using US system. Herein, we compared these two measurements in clinical US images. Thirty patient image sets where computed tomography (CT) and US images were captured less than 1 day apart were retrospectively reviewed. Five blinded reviewers independently assessed the largest stone in each image set for shadow presence and size. Shadow size was compared to US and CT stone sizes. Eighty percent of included stones demonstrated an acoustic shadow; 83% of stones without a shadow were ≤ 5 mm on CT. Average stone size was 6.5 ± 4.0 mm on CT, 10.3 ± 4.1 mm on US, and 7.5 ± 4.2 mm by shadow width. On average, US overestimated stone size by 3.8 ± 2.4 mm based on stone width (p < 0.001) and 1.0 ± 1.4 mm based on shadow width (p < 0.0098). Shadow measurements decreased misclassification of stones by 25% among three clinically relevant size categories (≤ 5, 5.1-10, > 10 mm), and by 50% for stones ≤ 5 mm. US overestimates stone size compared to CT. Retrospective measurement of the acoustic shadow from the same clinical US images is a more accurate reflection of true stone size than direct stone measurement. Most stones without a posterior shadow are ≤ 5 mm.

Cholecystolithiasis Is Associated with Clonorchis sinensis Infection

PubMed Central

Qiao, Tie; Ma, Rui-hong; Luo, Xiao-bing; Luo, Zhen-liang; Zheng, Pei-ming

2012-01-01

Background The objective of this study was to analyze gallbladder stones for direct evidence of a relationship between Clonorchis sinensis infection and gallbladder stones formation. Methodology We investigated one hundred eighty-three gallbladder stones for the presence of Clonorchis sinensis eggs using microscopy, and analyzed their composition using Fourier transform infrared spectroscopy. We confirmed the presence of Clonorchis sinensis eggs in the gallbladder stones using real-time fluorescent PCR and scanning electron microscopy. Principal Findings Clonorchis sinensis eggs were detected in 122 of 183 gallbladder stones based on morphologic characteristics and results from real-time fluorescent PCR. The proportion of pigment stones, cholesterol stones and mixed gallstones in the egg-positive stones was 79.5% (97/122), 3.3% (4/122) and 17.2% (21/122), respectively, while 29.5% (18/61), 31.1% (19/61) and 39.3% (24/61) in the egg-negative stones. The proportion of pigment stone in the Clonorchis sinensis egg-positive stones was higher than in egg-negative stones (P<0.0001). In the 30 egg-positive stones examined by scanning electron microscopy, dozens or even hundreds of Clonorchis sinensis eggs were visible (×400) showing a distinct morphology. Many eggs were wrapped with surrounding particles, and in some, muskmelon wrinkles was seen on the surface of the eggs. Also visible were pieces of texture shed from some of the eggs. Some eggs were depressed or without operculum while most eggs were adhered to or wrapped with amorphous particles or mucoid matter (×3000). Conclusion Clonorchis sinensis eggs were detected in the gallbladder stones which suggests an association between Clonorchis sinensis infection and gallbladder stones formation, especially pigment stones. PMID:22905137

Incidence and characteristics of kidney stones in patients with horseshoe kidney: A systematic review and meta-analysis

PubMed Central

Pawar, Aditya S.; Thongprayoon, Charat; Cheungpasitporn, Wisit; Sakhuja, Ankit; Mao, Michael A.; Erickson, Stephen B.

2018-01-01

Introduction: The horseshoe kidney (HSK) is the most common type of renal fusion anomaly. The incidence and characteristics of kidney stones in patients with HSK are not well studied. The aim of this meta-analysis was to evaluate the incidence and types of kidney stones in patients with HSK. Methods: A systematic literature search was performed using MEDLINE, EMBASE, and Cochrane Database of Systematic Reviews from the databases' inception through November 2016. Studies assessing the incidence and types of kidney stones in patients with HSK were included. We applied a random-effects model to estimate the incidence of kidney stones. The study protocol was registered with PROSPERO (International Prospective Register of Systematic Reviews; no. CRD42016052037). Results: A total of 14 observational studies with 943 patients (522 adults and 421 pediatric) with HSK were enrolled. The estimated pooled incidence of kidney stones was 36% (95% confidence interval [CI], 15%–59%) in adults with the HSK. Kidney stones were less common in pediatric patients with HSK with an estimated pooled incidence of 3% (95% CI, 2%–5%). The mean age of adult stone formers with HSK was 44.9 ± 6.2 years, and 75% were males. Within reported studies, 89.2% of kidney stones were calcium-based stones (64.2% calcium oxalate [CaOx], 18.8% calcium phosphate [CaP], and 6.2% mixed CaOx/CaP), followed by struvite stones (4.2%), uric acid stones (3.8%), and others (2.8%). Conclusions: Kidney stones are very common in adult patients with HSK with an estimated incidence of 36%. Calcium-based stones are the most prevalent kidney stones in adults with HSKs. These findings may impact the prevention and clinical management of kidney stones in patients with HSK. PMID:29416282

The natural history of nonobstructing asymptomatic renal stones managed with active surveillance.

PubMed

Dropkin, Benjamin M; Moses, Rachel A; Sharma, Devang; Pais, Vernon M

2015-04-01

We documented the natural history of asymptomatic nonobstructing renal calculi managed with active surveillance and explored factors predicting stone related events to better inform shared decision making. Patients with asymptomatic nonobstructing renal calculi electing active surveillance of their stone(s) were retrospectively reviewed. Stone characteristics, patient characteristics, and stone related events were collected. We evaluated the effects of stone size and location on development of symptoms, spontaneous passage, requirement for surgical intervention, and stone growth. We identified 160 stones with an average size of 7.0 ± 4.2 mm among 110 patients with average followup of 41 ± 19 months. Forty-five (28% of total) stones caused symptoms during followup. Notably 3 stones (3% of asymptomatic subgroup, 2% of total stones) caused painless silent obstruction necessitating intervention after an average of 37 ± 17 months. The only significant predictor of spontaneous passage or symptom development was location. Upper pole/mid renal stones were more likely than lower pole stones to become symptomatic (40.6% vs 24.3%, p = 0.047) and to pass spontaneously (14.5% vs 2.9%, p = 0.016). Among asymptomatic nonobstructing renal calculi managed with active surveillance, most remained asymptomatic through an average followup of more than 3 years. Less than 30% caused renal colic, less than 20% were operated on for pain and 7% spontaneously passed. Lower poles stones were significantly less likely to cause symptoms or pass spontaneously. Despite 3 stones causing silent hydronephrosis suggestive of obstruction, regular followup imaging facilitated interventions that prevented renal loss. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Accurately Diagnosing Uric Acid Stones from Conventional Computerized Tomography Imaging: Development and Preliminary Assessment of a Pixel Mapping Software.

PubMed

Ganesan, Vishnu; De, Shubha; Shkumat, Nicholas; Marchini, Giovanni; Monga, Manoj

2018-02-01

Preoperative determination of uric acid stones from computerized tomography imaging would be of tremendous clinical use. We sought to design a software algorithm that could apply data from noncontrast computerized tomography to predict the presence of uric acid stones. Patients with pure uric acid and calcium oxalate stones were identified from our stone registry. Only stones greater than 4 mm which were clearly traceable from initial computerized tomography to final composition were included in analysis. A semiautomated computer algorithm was used to process image data. Average and maximum HU, eccentricity (deviation from a circle) and kurtosis (peakedness vs flatness) were automatically generated. These parameters were examined in several mathematical models to predict the presence of uric acid stones. A total of 100 patients, of whom 52 had calcium oxalate and 48 had uric acid stones, were included in the final analysis. Uric acid stones were significantly larger (12.2 vs 9.0 mm, p = 0.03) but calcium oxalate stones had higher mean attenuation (457 vs 315 HU, p = 0.001) and maximum attenuation (918 vs 553 HU, p <0.001). Kurtosis was significantly higher in each axis for calcium oxalate stones (each p <0.001). A composite algorithm using attenuation distribution pattern, average attenuation and stone size had overall 89% sensitivity, 91% specificity, 91% positive predictive value and 89% negative predictive value to predict uric acid stones. A combination of stone size, attenuation intensity and attenuation pattern from conventional computerized tomography can distinguish uric acid stones from calcium oxalate stones with high sensitivity and specificity. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Risk Factors for Stone Recurrence after Percutaneous Nephrolithotomy

NASA Astrophysics Data System (ADS)

Krambeck, Amy E.; Rangel, Laureano J.; LeRoy, Andrew J.; Patterson, David E.; Gettman, Matthew T.

2008-09-01

Recent studies have demonstrated more than 30% of percutaneous nephrolithotomy (PCNL) patients will experience a stone recurrence over a 20 year period. The goal of our study was to identify risk factors for stone recurrence after PCNL. Chart review identified 754 patients treated with PCNL for urolithiasis from March of 1983 to July 1984 at our institution. Of this cohort, 87 patients continued to receive medical care at our clinic and had been evaluated within the last 5 years. Of the 87 patients, 80 had recent radiographic imaging. Average follow-up was 19.2 years and 32 (40.0%) experienced at least 1 stone recurrence. There was no difference in preoperative BMI (p = 0.453) or change in BMI (p = 0.964) between patients that did and did not have a stone recurrence. Renal stone location (p = 0.605) and stone size (p = 0.238) were not predictive of recurrence. Patients with calcium oxalate monohydrate stones were less likely to recur (38.7% vs. 41.6%, p = 0.004) and those with calcium oxalate dihydrate (COD) were more likely to recur (31.1% vs. 19.6%, p = 0.006) compared to other compositions. Diabetes mellitus was not associated with recurrent stones (p = 0.810). Those patients with residual stones or fragments <3 mm were more likely to recur and to recur earlier than patients rendered entirely stone free at time of PCNL (p = 0.015). Stone recurrences were associated with the late development of renal insufficiency (25% vs. 2.1%, p = 0.002). In conclusion, stone composition, as well as the presence of residual fragments was associated with recurrent symptomatic stone events after PCNL. Recurrent stone events were significantly associated with the risk of developing renal insufficiency, further stressing the need for complete stone clearance at time of PCNL.

A neural network - based algorithm for predicting stone -free status after ESWL therapy

PubMed Central

Seckiner, Ilker; Seckiner, Serap; Sen, Haluk; Bayrak, Omer; Dogan, Kazım; Erturhan, Sakip

2017-01-01

ABSTRACT Objective: The prototype artificial neural network (ANN) model was developed using data from patients with renal stone, in order to predict stone-free status and to help in planning treatment with Extracorporeal Shock Wave Lithotripsy (ESWL) for kidney stones. Materials and Methods: Data were collected from the 203 patients including gender, single or multiple nature of the stone, location of the stone, infundibulopelvic angle primary or secondary nature of the stone, status of hydronephrosis, stone size after ESWL, age, size, skin to stone distance, stone density and creatinine, for eleven variables. Regression analysis and the ANN method were applied to predict treatment success using the same series of data. Results: Subsequently, patients were divided into three groups by neural network software, in order to implement the ANN: training group (n=139), validation group (n=32), and the test group (n=32). ANN analysis demonstrated that the prediction accuracy of the stone-free rate was 99.25% in the training group, 85.48% in the validation group, and 88.70% in the test group. Conclusions: Successful results were obtained to predict the stone-free rate, with the help of the ANN model designed by using a series of data collected from real patients in whom ESWL was implemented to help in planning treatment for kidney stones. PMID:28727384

Chronic Kidney Disease in Kidney Stone Formers

PubMed Central

Krambeck, Amy E.; Lieske, John C.

2011-01-01

Summary Recent population studies have found symptomatic kidney stone formers to be at increased risk for chronic kidney disease (CKD). Although kidney stones are not commonly identified as the primary cause of ESRD, they still may be important contributing factors. Paradoxically, CKD can be protective against forming kidney stones because of the substantial reduction in urine calcium excretion. Among stone formers, those with rare hereditary diseases (cystinuria, primary hyperoxaluria, Dent disease, and 2,8 dihydroxyadenine stones), recurrent urinary tract infections, struvite stones, hypertension, and diabetes seem to be at highest risk for CKD. The primary mechanism for CKD from kidney stones is usually attributed to an obstructive uropathy or pyelonephritis, but crystal plugs at the ducts of Bellini and parenchymal injury from shockwave lithotripsy may also contribute. The historical shift to less invasive surgical management of kidney stones has likely had a beneficial impact on the risk for CKD. Among potential kidney donors, past symptomatic kidney stones but not radiographic stones found on computed tomography scans were associated with albuminuria. Kidney stones detected by ultrasound screening have also been associated with CKD in the general population. Further studies that better classify CKD, better characterize stone formers, more thoroughly address potential confounding by comorbidities, and have active instead of passive follow-up to avoid detection bias are needed. PMID:21784825

Regional differences in constituents of gall stones.

PubMed

Ashok, M; Nageshwar Reddy, D; Jayanthi, V; Kalkura, S N; Vijayan, V; Gokulakrishnan, S; Nair, K G M

2005-01-01

The pathogenesis of pigment and mixed gall stone formation remains elusive. The elemental constituents of gall stones from southern states of Tamil Nadu, Kerala and Karnataka have been characterized. Our aim was to determine the elemental concentration of representative samples of pigment, mixed and cholesterol gall stones from Andhra Pradesh using proton-induced X-ray emission (PIXE) using a 3 MV horizontal pelletron accelerator. Pigment gall stones had significantly high concentrations of copper, iron and lead; chromium was absent. Except for iron all these elements were significantly low in cholesterol gall stones and intermediate levels were seen in mixed gall stones. Highest concentrations of chromium was seen in cholesterol and titanium in mixed gall stones respectively; latter similar to other southern states. Arsenic was distinctly absent in cholesterol and mixed gall stones. The study has identified differences in elemental components of the gall stones from Andhra Pradesh.

Discards beneficiation in South Africa

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

Horsfall, D.W.

1995-08-01

The intergrown nature of most South African coals means that in beneficiating them, the preparation engineer rarely has the easy task of carrying out a simple separation between good coal and high density shale or stone. Apart from de-shaling operations, all beneficiation entails rejecting, not only adventitious stone but a large percentage of high ash but strongly combustible middlings material. Typically, a coal preparation plant can only recover about 70-80% of the heat in the run-of-mine coal. The other 20-30% ends up on the discard heap. Over the last decade, extensive studies were carried out to establish the extend tomore » which that discarded heat may be recoverable in marketable grades of coal. Detailed washability studies were carried out on four mines which between them produce almost 60% of the total make of discards. Computer simulations allowed different flowsheet configurations to be assessed to give rewashed coal of various calorific values. The flowsheets were also subjected to factorial establishment of budget capital and operating costs. Finally some initial work was carried out on the potential markets for such products. This paper is concise account of the results of the study for one major mine. Please note that the paper is based almost wholly on the evaluation carried out for the Energy Branch of the Department of Mineral and Energy Affairs (DMEA). The actual work was executed by the van Eck and Lurie Division of E L Bateman and Co. The writer chaired the Beneficiation Sub-Committee set up by the DMEA to oversee and guide the work, and in that capacity was closely connected with the study as it evolved. Other acknowledgements are given at the end of the paper.« less

Cholecystectomy for Prevention of Recurrence after Endoscopic Clearance of Bile Duct Stones in Korea.

PubMed

Song, Myung Eun; Chung, Moon Jae; Lee, Dong Jun; Oh, Tak Geun; Park, Jeong Youp; Bang, Seungmin; Park, Seung Woo; Song, Si Young; Chung, Jae Bock

2016-01-01

Cholecystectomy in patients with an intact gallbladder after endoscopic removal of stones from the common bile duct (CBD) remains controversial. We conducted a case-control study to determine the risk of recurrent CBD stones and the benefit of cholecystectomy for prevention of recurrence after endoscopic removal of stones from the CBD in Korean patients. A total of 317 patients who underwent endoscopic CBD stone extraction between 2006 and 2012 were included. Possible risk factors for the recurrence of CBD stones including previous cholecystectomy history, bile duct diameter, stone size, number of stones, stone composition, and the presence of a periampullary diverticulum were analyzed. The mean duration of follow-up after CBD stone extraction was 25.4±22.0 months. A CBD diameter of 15 mm or larger [odds ratio (OR), 1.930; 95% confidence interval (CI), 1.098 to 3.391; p=0.022] and the presence of a periampullary diverticulum (OR, 1.859; 95% CI, 1.014 to 3.408; p=0.045) were independent predictive factors for CBD stone recurrence. Seventeen patients (26.6%) in the recurrence group underwent elective cholecystectomy soon after endoscopic extraction of CBD stones, compared to 88 (34.8%) in the non-recurrence group; the difference was not statistically significant (p=0.212). A CBD diameter of 15 mm or larger and the presence of a periampullary diverticulum were found to be potential predictive factors for recurrence after endoscopic extraction of CBD stones. Elective cholecystectomy after clearance of CBD stones did not reduce the incidence of recurrent CBD stones in Korean patients.

[Correlation between urinary stones and urinary tract infections].

PubMed

Chen, Peilin; Zhang, Liguo; Meng, Bin

2014-05-01

To explore the correlation of urinary stones and urinary tract infections. 300 cases with urinary tract stones received in our hospital from Feb. 2010 to Oct. 2013 were chosen as study samples. Urine routine index, situation of urine positivity and urinary tract infection after surgery were analyzed while, intraoperative cotton swabs were tested after being dipped in liquid near stones. Main components of stones in non-infected and infected stone group were analyzed and compared. Data on urolithiasis was collected. 96 infected stones were found in 300 patients, accounting for 32%, which including 35 cases of E. coli (36.5%), 28 cases of Staphylococcus epidermidis (29.2%), and 15 cases of Proteus mirabilis (15.6%). Numbers of urine abnormalities, urine positivities, positive intraoperative cotton swabs and urinary tract infections in patients in the group with infected stones, were significantly higher than in the group without infected stones and the differences were statistically significant (χ² = 8.203, 73.99, 178.9, 24.26, P < 0.05). The incidence rates of hexahydrate magnesium ammonium phosphate, carbonate apatite and hydroxyapatite stones in the group with infected stones were significantly higher than those in the non-infected-rock group while the incidence rates of calcium oxalate and uric acid stones were found significantly lower than those in the non-infected-stone group, with differences statistically significant (χ² = 167.6, 21.00, 8.586, 73.17, 48.79, P < 0.05). Bacteria could cause urinary tract stones, and infected stones were always associated with urinary tract infections. Bacteria detection in patients with urinary calculi was particularly important to avoid the urinary tract infections.

30 CFR 291.101 - What definitions apply to this part?

Code of Federal Regulations, 2011 CFR

2011-07-01

... horizontal component or riser. Examples include anodes, valves, flanges, fittings, umbilicals, subsea... as a separate entity). Pipeline is the piping, risers, accessories and appurtenances installed for...

Rubber stopper remover

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

Stitt, Robert R.

1994-01-01

A device for removing a rubber stopper from a test tube is mountable to an upright wall, has a generally horizontal splash guard, and a lower plate spaced parallel to and below the splash guard. A slot in the lower plate has spaced-apart opposing edges that converge towards each other from the plate outer edge to a narrowed portion, the opposing edges shaped to make engagement between the bottom of the stopper flange and the top edge of the test tube to wedge therebetween and to grasp the stopper in the slot narrowed portion to hold the stopper as themore » test tube is manipulated downwardly and pulled from the stopper. The opposing edges extend inwardly to adjoin an opening having a diameter significantly larger than that of the stopper flange.« less

Note: O-ring stack system for electron gun alignment.

PubMed

Park, In-Yong; Cho, Boklae; Han, Cheolsu; Shin, Seungmin; Lee, Dongjun; Ahn, Sang Jung

2015-01-01

We present a reliable method for aligning an electron gun which consists of an electron source and lenses by controlling a stack of rubber O-rings in a vacuum condition. The beam direction angle is precisely tilted along two axes by adjusting the height difference of a stack of O-rings. In addition, the source position is shifted in each of three orthogonal directions. We show that the tilting angle and linear shift along the x and y axes as obtained from ten stacked O-rings are ±2.55° and ±2 mm, respectively. This study can easily be adapted to charged particle gun alignment and adjustments of the flange position in a vacuum, ensuring that its results can be useful with regard to electrical insulation between flanges with slight modifications.

Note: Development of target changeable palm-top pyroelectric x-ray tube

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

Imashuku, Susumu; Kawai, Jun

2012-01-15

A target changeable palm-top size x-ray tube was realized using pyroelectric crystal and detachable vacuum flanges. The target metals can be exchanged easily by attaching them on the brass stage with carbon tape. When silver and titanium palates (area: 10 mm{sup 2}) were used as targets, silver L{alpha} and titanium K lines were clearly observed by bombarding electrons on the targets for 90 s. The intensities were the same or higher than those of previously reported pyroelectric x-ray tubes. Chromium, iron, nickel, copper, and zinc K lines in the x-ray tube (stainless steel and brass) disappeared by replacing the brassmore » stage and the stainless steel vacuum flange with a carbon stage and a glass tube, respectively.« less

Self-adjustable supplemental support system for a cylindrical container in a housing

DOEpatents

Blaushild, Ronald M.

1987-01-01

A self-adjustable supplementary support system for a cylindrical container coaxially disposed in a cylindrical housing by upper flanged supports has a plurality of outwardly extending bracket units on the external surface of the container which coact with inwardly extending resiliently outwardly extending bracket units on the inner wall of the cylindrical housing. The bracket units have flanges which form a concave surface that seats on support bars, attached by links to torsion bars that are secured to ring segments annularly spaced about the inner wall of the cylindrical housing and the bracket units and support bars coact with each other to radially position and support the container in the housing during movement of the two components from a vertical to a horizontal position, and during transportation of the same.

Numerical Predictions of Mode Reflections in an Open Circular Duct: Comparison with Theory

NASA Technical Reports Server (NTRS)

Dahl, Milo D.; Hixon, Ray

2015-01-01

The NASA Broadband Aeroacoustic Stator Simulation code was used to compute the acoustic field for higher-order modes in a circular duct geometry. To test the accuracy of the results computed by the code, the duct was terminated by an open end with an infinite flange or no flange. Both open end conditions have a theoretical solution that was used to compare with the computed results. Excellent comparison for reflection matrix values was achieved after suitable refinement of the grid at the open end. The study also revealed issues with the level of the mode amplitude introduced into the acoustic held from the source boundary and the amount of reflection that occurred at the source boundary when a general nonreflecting boundary condition was applied.

Propagation and radiation of sound from flanged circular ducts with circumferentially varying wall admittances. I Semi-infinite ducts. II - Finite ducts with sources

NASA Technical Reports Server (NTRS)

Fuller, C. R.

1984-01-01

Sound propagation in infinite, semiinfinite, and finite circular ducts with circumferentially varying wall admittances is investigated analytically. The infinite case is considered, and an example demonstrates the effects of wall-admittance distribution on dispersion characteristics and mode shapes. An exact solution is obtained for the semiinfinite case, a circular duct with a flanged opening: sidelobe suppression and circumferential-mode energy scattering leading to radiated-field asymmetry are found. A finite duct system with specified hard-walled pressure sources is examined in detail, evaluating reflection coefficients, transmission losses, and radiated-field directivity. Graphs and diagrams are provided, and the implications of the results obtained for the design of aircraft-turbofan inlet liners are discussed.

High temperature penetrator assembly with bayonet plug and ramp-activated lock

NASA Technical Reports Server (NTRS)

Wood, K. E. (Inventor)

1982-01-01

A penetration apparatus, for very high temperature applications in which a base plug is inserted into an opening through a bulkhead is described. The base plug has a head shape and is seated against the highest temperature surface of the bulkhead, which may be the skin of the nose cone or other part of a space vehicle intended for nondestructive atmospheric reentry. From the second side of the bulkhead at which the less severe environment is extant, a bayonet plug is inserted into the base plug and engages an internal shoulder at about 90 deg rotation. The bayonet plug has an integral flanged portion and a pair of ramping washers which are located between the flange and the second bulkhead surface with a spacing washer as necessary.

A flange on electron spectromicroscope with spherical deflector analyzer--simultaneous imaging of reciprocal and real spaces.

PubMed

Grzelakowski, Krzysztof P

2013-07-01

An instrumental realization of the idea for the electron emission spectromicroscope based on the newly developed imaging energy filter called α-SDA (Spherical Deflector Analyzer) is reported. Its compact design enables the realization of the flange-on spectromicroscope concept. It is equipped with two independent energy selective imaging channels: one for real and another for reciprocal space visualization. These images can be acquired quasi-simultaneousely by means of the software based on the switching on and off potentials of the energy filter. An electron gun located inside the immersion objective lens allows a new kind of sample illumination by high energy primary electrons and thus, opens a new application field for electron spectromicroscopy under laboratory conditions. Copyright © 2013 Elsevier B.V. All rights reserved.

Comparative fixation methods of cervical disc arthroplasty versus conventional methods of anterior cervical arthrodesis: serration, teeth, keels, or screws?

PubMed

Cunningham, Bryan W; Hu, Nianbin; Zorn, Candace M; McAfee, Paul C

2010-02-01

Using a synthetic vertebral model, the authors quantified the comparative fixation strengths and failure mechanisms of 6 cervical disc arthroplasty devices versus 2 conventional methods of cervical arthrodesis, highlighting biomechanical advantages of prosthetic endplate fixation properties. Eight cervical implant configurations were evaluated in the current investigation: 1) PCM Low Profile; 2) PCM V-Teeth; 3) PCM Modular Flange; 4) PCM Fixed Flange; 5) Prestige LP; 6) Kineflex/C disc; 7) anterior cervical plate + interbody cage; and 8) tricortical iliac crest. All PCM treatments contained a serrated implant surface (0.4 mm). The PCM V-Teeth and Prestige contained 2 additional rows of teeth, which were 1 mm and 2 mm high, respectively. The PCM Modular and Fixed Flanged devices and anterior cervical plate were augmented with 4 vertebral screws. Eight pullout tests were performed for each of the 8 conditions by using a synthetic fixation model consisting of solid rigid polyurethane foam blocks. Biomechanical testing was conducted using an 858 Bionix test system configured with an unconstrained testing platform. Implants were positioned between testing blocks, using a compressive preload of -267 N. Tensile load-to-failure testing was performed at 2.5 mm/second, with quantification of peak load at failure (in Newtons), implant surface area (in square millimeters), and failure mechanisms. The mean loads at failure for the 8 implants were as follows: 257.4 +/- 28.54 for the PCM Low Profile; 308.8 +/- 15.31 for PCM V-Teeth; 496.36 +/- 40.01 for PCM Modular Flange; 528.03+/- 127.8 for PCM Fixed Flange; 306.4 +/- 31.3 for Prestige LP; 286.9 +/- 18.4 for Kineflex/C disc; 635.53 +/- 112.62 for anterior cervical plate + interbody cage; and 161.61 +/- 16.58 for tricortical iliac crest. The anterior plate exhibited the highest load at failure compared with all other treatments (p < 0.05). The PCM Modular and Fixed Flange PCM constructs in which screw fixation was used exhibited higher pullout loads than all other treatments except the anterior plate (p < 0.05). The PCM VTeeth and Prestige and Kineflex/C implants exhibited higher pullout loads than the PCM Low Profile and tricortical iliac crest (p < 0.05). Tricortical iliac crest exhibited the lowest pullout strength, which was different from all other treatments (p < 0.05). The surface area of endplate contact, measuring 300 mm(2) (PCM treatments), 275 mm(2) (Prestige LP), 250 mm(2) (Kineflex/C disc), 180 mm(2) (plate + cage), and 235 mm(2) (tricortical iliac crest), did not correlate with pullout strength (p > 0.05). The PCM, Prestige, and Kineflex constructs, which did not use screw fixation, all failed by direct pullout. Screw fixation devices, including anterior plates, led to test block fracture, and tricortical iliac crest failed by direct pullout. These results demonstrate a continuum of fixation strength based on prosthetic endplate design. Disc arthroplasty constructs implanted using vertebral body screw fixation exhibited the highest pullout strength. Prosthetic endplates containing toothed ridges (>or= 1 mm) or keels placed second in fixation strength, whereas endplates containing serrated edges exhibited the lowest fixation strength. All treatments exhibited greater fixation strength than conventional tricortical iliac crest. The current study offers insights into the benefits of various prosthetic endplate designs, which may potentially improve acute fixation following cervical disc arthroplasty.

Nutritional Management of Kidney Stones (Nephrolithiasis)

PubMed Central

Segal, Adam M.; Seifter, Julian L.; Dwyer, Johanna T.

2015-01-01

The incidence of kidney stones is common in the United States and treatments for them are very costly. This review article provides information about epidemiology, mechanism, diagnosis, and pathophysiology of kidney stone formation, and methods for the evaluation of stone risks for new and follow-up patients. Adequate evaluation and management can prevent recurrence of stones. Kidney stone prevention should be individualized in both its medical and dietary management, keeping in mind the specific risks involved for each type of stones. Recognition of these risk factors and development of long-term management strategies for dealing with them are the most effective ways to prevent recurrence of kidney stones. PMID:26251832

Villamayor stone (Golden Stone) as a Global Heritage Stone Resource from Salamanca (NW of Spain)

NASA Astrophysics Data System (ADS)

Garcia-Talegon, Jacinta; Iñigo, Adolfo; Vicente-Tavera, Santiago

2013-04-01

Villamayor stone is an arkosic stone of Middle Eocene age and belongs to the Cabrerizos Sandstone Formation that comprising braided fluvial systems and paleosoils at the top of each stratigraphic sequence. The sandstone is known by several names: i) the Villamayor Stone because the quarries are located in Villamayor de Armuña village that are situated at 7 km to the North from Salamanca city; ii) the Golden Stone due to its patina that produced a ochreous/golden color on the façades of monuments of Salamanca (World Heritage City,1988) built in this Natural stone (one of the silicated rocks utilised). We present in this work, the Villamayor Stone to be candidate as Global Heritage Stone Resource. The Villamayor Stone were quarrying for the construction and ornamentation of Romanesque religious monuments as the Old Cathedral and San Julian church; Gothic (Spanish plateresc style) as the New Cathedral, San Esteban church and the sculpted façade of the Salamanca University, one of the oldest University in Europe (it had established in 1250); and this stone was one of the type of one of the most sumptuous Baroque monuments is the Main Square of the its galleries and arcades (1729). Also, this stone was used in building palaces, walls and reconstruction of Roman bridge. Currently, Villamayor Stone is being quarried by small and family companies, without a modernized processing, for cladding of the façades of the new buildings until that the construction sector was burst (in 2008 the international economic crisis). However, Villamayor Stone is the main stone material used in the city of Salamanca for the restoration of monuments and, even in small quantities when compared with just before the economic crisis, it would be of great importance for future generations protect their quarries and the craft of masonry. Villamayor Stone has several varieties from channels facies to floodplains facies, in this work the selected varieties are: i) the fine-grained stone, microporous, is partially cemented by dolomite, 27% (bulk porosity), ii) the ochre and fine-grained stone, microporous, with smectite, 30% (bulk porosity), iii) the medium-grained stone, 38% (bulk porosity). Main components for all three varieties: Quartz (up to 60%), feldspars, 2:1 layered silicates (smectites), palygorskite-type fibrous silicates, and small amounts of micaceous minerals (illite/mica).

Extensive characterizations of bacteria isolated from catheterized urine and stone matrices in patients with nephrolithiasis.

PubMed

Tavichakorntrakool, Ratree; Prasongwattana, Vitoon; Sungkeeree, Seksit; Saisud, Phitsamai; Sribenjalux, Pipat; Pimratana, Chaowat; Bovornpadungkitti, Sombat; Sriboonlue, Pote; Thongboonkerd, Visith

2012-11-01

Urinary tract infections are generally known to be associated with nephrolithiasis, particularly struvite stone, in which the most common microbe found is urea-splitting bacterium, i.e. Proteus mirabilis. However, our observation indicated that it might not be the case of stone formers in Thailand. We therefore extensively characterized microorganisms associated with all types of kidney stones. A total of 100 kidney stone formers (59 males and 41 females) admitted for elective percutaneous nephrolithotomy were recruited and microorganisms isolated from catheterized urine and cortex and nidus of their stones were analyzed. From 100 stone formers recruited, 36 cases had a total of 45 bacterial isolates cultivated from their catheterized urine and/or stone matrices. Among these 36 cases, chemical analysis by Fourier-transformed infrared spectroscopy revealed that 8 had the previously classified 'infection-induced stones', whereas the other 28 cases had the previously classified 'metabolic stones'. Calcium oxalate (in either pure or mixed form) was the most common and found in 64 and 75% of the stone formers with and without bacterial isolates, respectively. Escherichia coli was the most common bacterium (approximately one-third of all bacterial isolates) found in urine and stone matrices (both nidus and periphery). Linear regression analysis showed significant correlation (r = 0.860, P < 0.001) between bacterial types in urine and stone matrices. Multidrug resistance was frequently found in these isolated bacteria. Moreover, urea test revealed that only 31% were urea-splitting bacteria, whereas the majority (69%) had negative urea test. Our data indicate that microorganisms are associated with almost all chemical types of kidney stones and urea-splitting bacteria are not the major causative microorganisms found in urine and stone matrices of the stone formers in Thailand. These data may lead to rethinking and a new roadmap for future research regarding the role of microorganisms in kidney stone formation.

Contribution of stone size to chronic kidney disease in kidney stone formers.

PubMed

Ahmadi, Farrokhlagha; Etemadi, Samira Motedayen; Lessan-Pezeshki, Mahbob; Mahdavi-Mazdeh, Mitra; Ayati, Mohsen; Mir, Alireza; Yazdi, Hadi Rokni

2015-01-01

To determine whether stone burden correlates with the degree of chronic kidney disease in kidney stone formers. A total of 97 extracorporeal shockwave lithotripsy candidates aged 18 years and older were included. Size, number and location of the kidney stones, along with cumulative stone size, defined as the sum of diameters of all stones) were determined. Estimated glomerular filtration rate was determined using the Chronic Kidney Disease Epidemiology Collaboration cystatin C/creatinine equation, and chronic kidney disease was defined as estimated glomerular filtration rate <60 mL/min/1.73 m(2). In individuals with cumulative stone size <20 mm, estimated glomerular filtration rate significantly decreased when moving from the first (estimated glomerular filtration rate 75.5 ± 17.8 mL/min/1.73 m(2)) to the fourth (estimated glomerular filtration rate 56.4 ± 20.44 mL/min/1.73 m(2) ) quartile (P = 0.004). When patients with a cumulative stone size ≥ 20 mm were included, the observed association was rendered non-significant. In individuals with a cumulative stone size < 20 mm, each 1-mm increase in cumulative stone size was associated with a 20% increased risk of having chronic kidney disease. The relationship persisted even after adjustment for age, sex, body mass index, C-reactive protein, fasting plasma glucose, thyroid stimulating hormone, presence of microalbuminuria, history of renal calculi, history of extracorporeal shockwave lithotripsy, number and location of the stones (odds ratio 1.24, 95% confidence interval 1.02-1.52). The same was not observed for individuals with a cumulative stone size ≥ 20 mm. In kidney stone formers with a cumulative stone size up to 20 mm, estimated glomerular filtration rate linearly declines with increasing cumulative stone size. Additionally, cumulative stone size is an independent predictor of chronic kidney disease in this group of patients. © 2014 The Japanese Urological Association.

Risk of Hypertension among First-Time Symptomatic Kidney Stone Formers

PubMed Central

Kittanamongkolchai, Wonngarm; Mara, Kristin C.; Mehta, Ramila A.; Vaughan, Lisa E.; Denic, Aleksandar; Knoedler, John J.; Enders, Felicity T.; Lieske, John C.

2017-01-01

Background and objectives Prior work has suggested a higher risk of hypertension in kidney stone formers but lacked disease validation and adjustment for potential confounders. Certain types of stone formers may also be at higher risk of hypertension. Design, setting, participants, & measurements In our study, incident symptomatic stone formers in Olmsted County from 2000 to 2011 were manually validated by chart review and age and sex matched to Olmsted County controls. We followed up patients through November 20, 2015. Hypertension was also validated by manual chart review, and the risk of hypertension in stone formers compared with controls was assessed both univariately and after adjusting for comorbidities. The risk of hypertension among different subtypes of stone formers was also evaluated. Results Among 3023 coded stone formers from 2000 to 2011, a total of 1515 were validated and matched to 1515 controls (mean age was 45 years old, and 56% were men). After excluding those with baseline hypertension (20% of stone formers and 18% of controls), 154 stone formers and 110 controls developed hypertension. Median follow-up time was 7.8 years in stone formers and 9.6 years in controls. Stone formers were found to have a higher risk of hypertension compared with controls (hazard ratio, 1.50; 95% confidence interval, 1.18 to 1.92), even after adjusting for age, sex, body mass index, serum creatinine, CKD, diabetes, gout, coronary artery disease, dyslipidemia, tobacco use, and alcohol abuse (hazard ratio, 1.58; 95% confidence interval, 1.12 to 2.21). Results were similar after excluding patients who were ever on a thiazide diuretic (hazard ratio, 1.65; 95% confidence interval, 1.16 to 2.38). Stone composition, radiographic stone burden, number of subsequent stone events, and stone removal surgeries were not associated with hypertension (P>0.05 for all). Conclusions The risk of hypertension was higher after the first symptomatic kidney stone event. However, kidney stone severity, type, and treatment did not associate with hypertension. PMID:28148559

Has the pelvic renal stone position inside the upper loop of JJ stent any influence on the extracorporeal shock wave lithotripsy results?

PubMed

Pricop, Catalin; Serban, Dragomir N; Serban, Ionela Lacramioara; Cumpanas, Alin-Adrian; Gingu, Constantin-Virgil

2016-01-01

JJ stents are often encountered in patients with pelvic renal stones referred for shock wave lithotripsy, most of them being placed either for obstructive renal pelvic stones or for ureteric stones mobilized retrograde during the JJ stent insertion. The aim of the study was to determine whether the relative stone position in the upper loop of the JJ stent during extracorporeal shock wave lithotripsy (SWL) influences the efficiency of the procedure. The study was designed as a prospective cohort study on 162 patients addressing the same urological department, with single renal pelvic stone (primary or mobilized to the renal pelvis during the insertion of JJ stent), smaller than 15 mm, with JJ stent, treated by SWL using a second generation spark gap lithotripter, 18 kV, 3000 waves/session. Patients were divided in three groups according to the relative position of the stone to the upper loop of the JJ stent as appears on plain X-ray: stone-inside-loop, loop-crossing-stone and stone-outside the loop. The SWL success rate was the primary outcome of the study. p Value, Chi square and Kruskal-Wallis tests were used for statistical analysis. For stone-inside-loop cases, SWL efficiency was 22.7 versus 42 % for all the other cases (p = 0.002). Other factors for decreased SWL success rate were: higher stone radio-opacity, larger JJ of stent and obese patients. Study limitation is represented by the relative small study group and by the evaluation of stone density using plain X-ray instead of computer tomography. For pelvic renal stones having the same density characteristics studied by plain X-ray, the SWL efficiency is lower in stone-inside-loop cases comparing with the other positions. The overall stone free rate for renal pelvic stones could be explained by the second generation lithotripter used for all procedures.

Wanted: suitable replacement stones for the Lede stone (Belgium)

NASA Astrophysics Data System (ADS)

De Kock, T.; Dewanckele, J.; Boone, M. A.; De Boever, W.; De Schutter, G.; Jacobs, P.; Cnudde, V.

2012-04-01

The Lede stone is an arenaceous limestone with a Lutetian age, occurring as discrete (most of the times three) stone banks in the marine sandy sediments of the Lede Formation (Belgium). It has a quartz content of approximate 40%. This increases abrasion strength and together with the cementation results in an average compressive strength of about 80-85 MPa. The cement is a microsparitic calcite cement. Other carbonate particles are both microfossils (mainly foraminifers) and macrofossils (bivalves, serpulids, echinoderms, …). This great diversity gives the stone a heterogeneous, animated appearance. The intra- and interparticle porosity is in total 5-10 % in average and the apparent density is 2400-2550 kg/m3. Another important constituent is glauconite, present in a few percent. In fresh state, the stone has a greenish-grey colour, but when it is exposed to atmospheric conditions for a couple of years, the stone acquires a yellowish to rust-coloured patina due to the weathering of glauconite. Sulphatation causes severe damage to the stone, and black gypsum crusts are common in urban environments on stones protected from runoff. This stone was excavated in both open air and underground quarries in the areas of Brussels and Ghent. The proximity of main rivers such as the Scheldt and Zenne provided transport routes for export towards the north (e.g. Antwerp and The Netherlands). Its first known use dates back to Roman times but the stone flourished in Gothic architecture due to its easy workability and its 'divine' light coloured patina. This results nowadays in a dominant occurrence in the cultural heritage of northwestern Belgium and the south of The Netherlands. Socio-economical reasons caused several declines and revivals of Lede stone in use. In the beginning of the 20th century, only a few excavation sites remained, with as main quarry the one located at Bambrugge (Belgium). By the end of the first half of the 20th century, however, no quarry sites remained. In the sixties, a sand quarry located in Balegem (Belgium) started with the extraction of Lede stone combined with its other activities. Until now, only this site supplies blocks of fresh Lede stones and it doesn't seem there will rise an opportunity of a new site in the near future. Therefore, during the huge amount of renovation works in the past century, the Lede stone was often replaced by imported (mostly French) limestones such as Massangis stone, Savonnières stone and Euville stone. The commercial value seems to have had a large impact and too little attention was paid on the optical appearance, ageing and technical compatibility of the stones. The use of especially Massangis stone was taken for granted. In the 21st century, there is a growing awareness of the impact of such consequent replacement for the historical value of our cultural heritage and several alternative stones are suggested and even used. These include stones from France, Spain and Portugal, but also from other regions in Belgium. For the moment, there is no consensus on the most appropriate replacement stone and further research should be done in order to evaluate compatibility of the different stone types with Lede stone. In this context, it is also very important to actively search for better alternatives, which resemble the Lede stone in both a mechanical and aesthetical point of view. Therefore, this abstract is an open question to its readers. Any commercial natural stone suggestions with affiliation to the aforementioned properties are welcome by e-mailing the corresponding author.

Urinary Tract Stones and Osteoporosis: Findings From the Women’s Health Initiative

PubMed Central

Carbone, Laura D; Hovey, Kathleen M; Andrews, Christopher A; Thomas, Fridtjof; Sorensen, Mathew D; Crandall, Carolyn J; Watts, Nelson B; Bethel, Monique; Johnson, Karen C

2017-01-01

Kidney and bladder stones (urinary tract stones) and osteoporosis are prevalent, serious conditions for postmenopausal women. Men with kidney stones are at increased risk of osteoporosis; however, the relationship of urinary tract stones to osteoporosis in postmenopausal women has not been established. The purpose of this study was to determine whether urinary tract stones are an independent risk factor for changes in bone mineral density (BMD) and incident fractures in women in the Women’s Health Initiative (WHI). Data were obtained from 150,689 women in the Observational Study and Clinical Trials of the WHI with information on urinary tract stones status: 9856 of these women reported urinary tract stones at baseline and/or incident urinary tract stones during follow-up. Cox regression models were used to determine the association of urinary tract stones with incident fractures and linear mixed models were used to investigate the relationship of urinary tract stones with changes in BMD that occurred during WHI. Follow-up was over an average of 8 years. Models were adjusted for demographic and clinical factors, medication use, and dietary histories. In unadjusted models there was a significant association of urinary tract stones with incident total fractures (HR 1.10; 95% CI, 1.04 to 1.17). However, in covariate adjusted analyses, urinary tract stones were not significantly related to changes in BMD at any skeletal site or to incident fractures. In conclusion, urinary tract stones in postmenopausal women are not an independent risk factor for osteoporosis. PMID:25990099

Should metabolic evaluation be performed in patients with struvite stones?

PubMed

Iqbal, Muhammad Waqas; Shin, Richard H; Youssef, Ramy F; Kaplan, Adam G; Cabrera, Fernando J; Hanna, Jonathan; Scales, Charles D; Ferrandino, Michael N; Preminger, Glenn M; Lipkin, Michael E

2017-04-01

Previous studies suggested that patients with pure struvite calculi rarely have underlying metabolic abnormalities. Therefore, most of these patients do not undergo metabolic studies. We report our experience with these patients and their response to directed medical therapy. Between 1/2005 and 9/2012, 75 patients treated with percutaneous nephrolithotomy for struvite stones were identified. Of these, 7 had pure struvite stones (Group 1), 32 had mixed struvite stones (Group 2), both with metabolic evaluation, and 17 had pure struvite stones without metabolic evaluation (Group 3). The frequency of metabolic abnormalities and stone activity (defined as stone growth or stone-related events) was compared between groups. The median age was 55 years and 64 % were female. No significant difference in race, infection history, family history, stone location or volume existed between groups. Metabolic abnormalities were found in 57 % of Group 1 and 81 % of Group 2 patients. A similar proportion of Group 1 and 2 patients received modification to or continuation of metabolic therapy, whereas no Group 3 patients received any directed therapy. In patients with >6 months follow-up, the stone activity rate between Groups 1 and 2 appeared similar whereas Group 3 trended towards higher stone activity rate. Metabolic abnormalities in pure struvite stone formers appear to be more common than previously reported. Directed medical therapy in these patients may reduce stone activity. The role of metabolic evaluation and directed medical therapy needs reconsideration in patients with pure struvite stones.

[Management of Intrahepatic Duct Stone].

PubMed

Cha, Sang Woo

2018-05-25

Intrahepatic duct (IHD) stone is the presence of calculi within the intrahepatic bile duct specifically located proximal to the confluence of the left and right hepatic ducts. This stone is characterized by its intractable nature and frequent recurrence, requiring multiple therapeutic interventions. Without proper treatment, biliary strictures and retained stones can lead to repeated episodes of cholangitis, liver abscesses, secondary biliary cirrhosis, portal hypertension, and death from sepsis or hepatic failure. The ultimate treatment goals for IHD stones are complete removal of the stone, the correction of the associated strictures, and the prevention of recurrent cholangitis. A surgical resection can satisfy the goal of treatment for hepatolithiasis, i.e., complete removal of the IHD stones, stricture, and the risk of cholangiocarcinogenesis. On the other hand, in some cases, such as bilateral IHD stones, surgery alone cannot achieve these goals. Therefore, the optimal treatments require a multidisciplinary approach, including endoscopic and radiologic interventional procedures before and/or after surgery. Percutaneous transhepatic cholangioscopic lithotomy (PTCS-L) is particularly suited for patients at poor surgical risk or who refuse surgery and those with previous biliary surgery or stones distributed in multiple segments. PTCS-L is relatively safe and effective for the treatment of IHD stones, and complete stone clearance is mandatory to reduce the sequelae of IHD stones. An IHD stricture is the main factor contributing to incomplete clearance and stone recurrence. Long-term follow-up is required because of the overall high recurrence rate of IHD stones and the association with cholangiocarcinoma.

Preventing stone retropulsion during intracorporeal lithotripsy.

PubMed

Elashry, Osama M; Tawfik, Ahmad M

2012-12-01

Several studies of ureteroscopic treatment for ureteral stones have reported that most stone clearance failures can be attributed to stone fragment retropulsion. Stone retropulsion can result in increased operative time and cost-resulting from the need to change from the semi-rigid ureteroscope to a flexible instrument to chase migrated calculi-and additional procedures to treat residual migrated fragments are often required. The degree of migration depends mainly on the energy source used for lithotripsy; pneumatic and electrohydraulic lithotripters are associated with a greater degree of retropulsion than lasers. Different stone-trapping strategies and devices have been developed to minimize stone migration. Novel devices include the Lithovac(®) suction device, the Passport(™) balloon, the Stone Cone(™), the PercSys Accordion(®), the NTrap(®), and stone baskets such as the LithoCatch(™), the Parachute(™), and the Escape(®). Some authors have also reported on the use of lubricating jelly and BackStop(®) gel (a reverse thermosensitive polymeric plug); these devices are instilled proximal to the stone prior to the application of kinetic energy in order to prevent retrograde stone migration.

Evaluation of biochemical urinary stone composition and its relationship to tap water hardness in Qom province, central Iran.

PubMed

Moslemi, Mohammad Kazem; Saghafi, Hossein; Joorabchin, Seyed Mohammad Amin

2011-01-01

The aim of this study was to evaluate the biochemical stone composition in general population of Qom province, central Iran, and its relationship with high tap water hardness. In a prospective study, from March 2008 to July 2011, biochemical analysis of urinary stones in patients living in Qom province for at least 5 years was performed. Stones were retrieved by spontaneous passage, endoscopic or open surgery, and after extracorporeal shockwave lithotripsy. Demographic findings and the drinking water supply of patients were evaluated and compared with biochemical stone analysis. Stone analysis was performed in 255 patients. The most dominant composition of urinary stones was calcium oxalate (73%), followed by uric acid (24%), ammonium urate (2%), and cystine (1%). The peak incidence of urinary stone was in patients in their forties. Overall male to female ratio was 4.93:1. The dominant stone composition in inhabitants of central Iran, where tap water hardness is high, was calcium oxalate stones. On the basis of this study, biochemical urinary stone composition of Qom does not differ from other regions of Iran with lower water hardness.

Pathophysiology of kidney, gallbladder and urinary stones treatment with herbal and allopathic medicine: A review

PubMed Central

Alok, Shashi; Jain, Sanjay Kumar; Verma, Amita; Kumar, Mayank; Sabharwal, Monika

2013-01-01

Medicinal plants have been known for millennia and are highly esteemed all over the world as a rich source of therapeutic agents for the prevention of various ailments. Today large number of population suffers from kidney stone, gall stone and urinary calculi. Stone disease has gained increasing significance due to changes in living conditions i.e. industrialization and malnutrition. Changes in prevalence and incidence, the occurrence of stone types and stone location, and the manner of stone removal are explained. Medicinal plants are used from centuries due to its safety, efficacy, cultural acceptability and lesser side effects as compared to synthetic drugs. The present article deals with measures to be adopted for the potential of medicinal plants in stone dissolving activity. The problem of urinary stones or calculi is a very ancient one and many remedies have been employed during the ages these stones are found in all parts of the urinary tract, the kidney, the ureters and the urinary bladder and may vary considerably in size. In the present article, an attempt has been made to emphasis on herbal option for urinary stone.

30 CFR 291.101 - What definitions apply to this part?

Code of Federal Regulations, 2012 CFR

2012-07-01

... component or riser. Examples include anodes, valves, flanges, fittings, umbilicals, subsea manifolds...). Pipeline is the piping, risers, accessories and appurtenances installed for transportation of oil and gas...

30 CFR 291.101 - What definitions apply to this part?

Code of Federal Regulations, 2013 CFR

2013-07-01

... component or riser. Examples include anodes, valves, flanges, fittings, umbilicals, subsea manifolds...). Pipeline is the piping, risers, accessories and appurtenances installed for transportation of oil and gas...

30 CFR 291.101 - What definitions apply to this part?

Code of Federal Regulations, 2014 CFR

2014-07-01

... component or riser. Examples include anodes, valves, flanges, fittings, umbilicals, subsea manifolds...). Pipeline is the piping, risers, accessories and appurtenances installed for transportation of oil and gas...

Prediction of calcium level in melamine-related urinary calculi with helical CT: diagnostic performance evaluation and clinical significance.

PubMed

Yuan, Li; Xiaorui, Ru; Gang, Huang; Xinsheng, Xi; Xiaogang, Huang; Li, Dong; Yirong, Chen

2012-06-01

The aim of the study was to investigate the relationship between CT-attenuation and stone calcium level in melamine-related urinary calculi (MRUC). A total of 25 MRUC with known composition and calcium level were included (11 uric acid stones, 2 calcium oxalate stones and 12 mixture stones of uric acid and calcium oxalate). Of all, 18 renal stones accepted alkalization therapy except for 5 lower urinary tract stones and 2 stones of unknown position. With well-matched composition, 61 adult urinary stones were included as controls. Every stone was scanned by helical CT (80 kV/120 kV, 300 mA, pitch 0.625 mm) and the highest CT-attenuation value measured. CT-attenuation values of MRUC increased gradually from uric acid stones, mixture stones to calcium oxalate stones, but were always lower than the values of controls. Furthermore, a strong positive correlation was found between stone CT-attenuation value and stone calcium level (n = 25, r (80kV) = 0.883, p = 0.000; r (120kV) = 0.855, p = 0.000). Compared with alkalization-therapy-alone group, stone CT-attenuation values and stone calcium level in the comprehensive-therapy group were significantly greater (CT(80kV) 1,057 ± 639 vs. 172 ± 61 HU, p = 0.001; CT(120kV) 783 ± 476 vs. 162 ± 60 HU, p = 0.001; Ca 19.83 ± 7.48% vs. 1.30 ± 1.51%, p = 0.000). Fisher's exact test suggested that the stones with higher CT-attenuation values tended to resist alkalization when 400 HU served as the cutoff value (P (80kV) = 0.002, P (120kV) = 0.000). In conclusion, the study was the first to illustrate that the CT-attenuation value could reflect calcium level in MRUC and found that stones with higher CT-attenuation value were not amenable to alkalization because they probably contained greater calcium. For those patients, we believe that comprehensive therapy will be the best choice.

Mineralogy and chemistry of urinary stones: patients from North Jordan.

PubMed

Abboud, Iyad Ahmed

2008-10-01

Urinary stone diseases are increasing in the Middle East. The majority of urinary stone cases are found in the northern part of the country. Stone samples taken from patients living in the Irbid area were collected from Princess Basma Hospital. The present study concentrates on the mineralogical and chemical composition of the urinary stones and on the effective environmental factors that assist in developing the different types of urinary stones. Using X-ray diffraction techniques, the mineralogical composition of the urinary stones was found to be as follows: oxalate, cholesten, and uric acid, with cystine stones occuring more frequently than the others. Cholesten and calcium oxalate stones are the most dominant types of stones. Calcium oxalate is the most common type of oxalate stone. Calcium oxalate is represented in: whewellite, wheddellite, and calcium carbonate oxalate hydrate minerals, in addition to other minerals such as brushite, ammonium phosphate, vaterite, valleriite, and bobierrite from other types of stones. Bobierrite (phosphate group) is a new mineral reported in urinary stones, and this has not been determined in any previous study worldwide. Apatite (calcium phosphate) is deduced using scanning electron microscope (SEM) images. The SEM technique determined crystal forms and systems, shapes, morphological features, and the names of the minerals forming urine stones, while optical properties are studied by polarizing microscope. X-ray fluorescence technique determined the concentrations of major and some trace elements. It revealed that Ca is the main constituent of the urinary stones, especially those composed of calcium oxalate and calcium phosphate. The concentration of trace elements was Ba = 1.57, P = 3.61, Fe = 1.78, S = 2.08, Zr = 4.63, Mo = 3.92, Cu = 1.89, Co = 1.56, and F = 4.2% and was higher in the urinary stones of Jordanian patients than in foreigners in the country. Questionnaires completed by patients suggest that the most significant factors directly effecting the formation of stones are water, climate conditions, food rich in protein and rich in different chemicals. Moreover, some drugs and diseases might also help in developing other stones.

Calcium Tartrate Tetrahydrate, Case Report of a Novel Human Kidney Stone.

PubMed

Kleinguetl, Colin; Williams, James C; Ibrahim, Samar A; Daudon, Michel; Bird, Erin T; El Tayeb, Marawan M

2017-01-01

Background: Calcium tartrate tetrahydrate has been reported as the main mineral in urinary stones in rats that have significant tartrate in their diet, but in humans, there has been only one mention of calcium tartrate stones in the form of bladder stone, and that case was in Africa. Case Presentation: Patient is a 34-year-old Caucasian male who presented with typical symptoms of nephrolithiasis. CT abd/pelvis (renal stone protocol) revealed a 2 cm nonobstructing stone of the right renal pelvis. Patient underwent an uncomplicated right percutaneous nephrolithotomy and was noted to be stone free after surgery. Stone analysis was difficult with regard to determining composition, but was finally identified as calcium tartrate tetrahydrate. Conclusion: This was an unusual case, as this is the first recorded case of a calcium tartrate tetrahydrate outside of Africa. This type of stone had only been mainly described in rat models with dl- bitartrate in their diet. Our patient was an otherwise healthy, relatively muscular individual with no obvious source for this stone other than a vitamin and amino acid supplement that he takes regularly that contains l-carnitine (as tartrate) and choline (as bitartrate and citrate). The prevalence of this stone type is presently unknown, as stone analysis laboratories have not had the ability to recognize it. Although a connection between the supplement and stone formation is conjecture at this time, we believe this necessitates further investigation.

Quantification of the Range of Motion of Kidney and Ureteral Stones During Shockwave Lithotripsy in Conscious Patients.

PubMed

Harrogate, Suzanne R; Yick, L M Shirley; Williams, James C; Cleveland, Robin O; Turney, Benjamin W

2016-04-01

Effective shockwave lithotripsy requires accurate targeting of the stone throughout the course of treatment. Stone movement secondary to respiratory movement can make this more difficult. In vitro work has shown that stone motion outside the focal region reduces the efficacy of stone fragmentation; however, there are few clinical data on the degree of stone movement in patients during treatment. To investigate this, X-ray fluoroscopic images of the kidney and ureteral stones at the upper and lower limits of the normal respiratory cycle were acquired during shock wave lithotripsy of 58 conscious patients, and stone excursion was calculated from these images. In addition, the respiration rate and patient perceived pain were recorded during the course of the treatment. It was found that stone motion secondary to respiration was 7.7 ± 2.9 mm for kidney stones and 3.6 ± 2.1 mm for ureteral stones-less than has been reported in studies with anesthetized patients. There was no significant change of motion over the course of treatment although pain was found to increase. These data suggest that stone motion in conscious patients is less than in anesthetized patients. Furthermore, it suggests that lithotripters with focal regions of 8 mm or greater should not suffer from a marked drop in fragmentation efficiency due to stone motion.

Pathogenesis of pigment gallstones in Western societies: the central role of bacteria.

PubMed

Stewart, Lygia; Oesterle, Adair L; Erdan, Ihsan; Griffiss, J MacLeod; Way, Lawrence W

2002-01-01

Bacteria are traditionally accorded a greater role in pigment gallstone formation in Eastern populations. Stone color is thought to predict the presence of bacteria; that is, black stones (Western predominant) are supposedly sterile and brown stones (Eastern predominant) contain bacteria. We previously reported that, regardless of appearance, most pigment gallstones contain bacteria. This study examined, in a large Western population (370 patients), the incidence, appearance, and chemical composition of pigment stones, and the characteristics of gallstone bacteria. One hundred eighty-six pigment stones were obtained aseptically. Bacteria were detected by means of scanning electron microscopy and gallstone culture. Chemical composition was determined by infrared spectroscopy. Bacteria were tested for slime and beta-glucuronidase production. Seventy-three percent of pigment stones contained bacteria. Choledocholithiasis was associated with gallstone bacteria. Ca-bilirubinate was present in all pigment stones. Ca-palmitate was characteristic of infected stones, and more than 75% Ca-carbonate was characteristic of sterile stones. Neither chemical composition nor stone appearance predicted the presence of bacteria. Ninety-five percent and 67% of infected pigment stones contained bacteria that produced slime and beta-glucuronidase, respectively. Most pigment stones contained bacteria that produced beta-glucuronidase, slime, and phospholipase, factors that facilitate stone formation. Thus bacteria have a major role in Western pigment gallstone formation. Furthermore, gallstone color did not predict composition or bacterial presence.

Sedimentary rocks in our mouth: dental pulp stones made by nanobacteria

NASA Astrophysics Data System (ADS)

Ciftcioglu, Neva; Ciftcioglu, Vefa; Vali, Hojatollah; Turcott, Eduardo; Kajander, E. Olavi

1998-07-01

The mechanisms of dental pulp stone formation are still largely unknown. Pulp stones are mainly composed of carbonate apatite. Only few experimental reports have elucidated the potential of some selected bacteria to produce apatite under in vitro conditions using special calcification media. The tested stone forming bacteria were, in fact, often better known for their cariogenic potential. Our preliminary work with 18 dental pulp stones from Turkey, selected only by severity of the stone formation, indicated the presence of nanobacterial antigens in the demineralized stones. Furthermore, high incidence of kidney stones and gall stones in the patient group and in their parents was found. This raises the implication that nanobacteria may enter the body also via oral route, in addition to the parenteral and transplacental routes. The role of nanobacteria in dental pulp stone formation was further studied by following nanobacterial colonization and mineral formation on human tooth in vitro. Two molar teeth, one having pulp stone and one without, were vertically cut into two pieces, sterilized by autoclaving and incubated with or without nanobacteria in DMEM. Electron microscopic observations indicate that nanobacteria can cause apatite stone formation on tooth surface. The sever from of dental pulp stone formation might be associated with nanobacteria. This form of dental disease results in loss of teeth due to osteolytic processes. This addresses the necessity for a study on unconventional mineral-forming bacteria as a cause for human diseases.

Wild capuchin monkeys spontaneously adjust actions when using hammer stones of different mass to crack nuts of different resistance.

PubMed

Liu, Qing; Fragaszy, Dorothy M; Visalberghi, Elisabetta

2016-09-01

Expert tool users are known to adjust their actions skillfully depending on aspects of tool type and task. We examined if bearded capuchin monkeys cracking nuts with stones of different mass adjusted the downward velocity and the height of the stone when striking palm nuts. During a field experiment carried out in FBV (Piauí, Brazil), eight adult wild capuchin monkeys (five males) cracked Orbygnia nuts of varied resistance with hammer stones differing in mass. From recorded videos, we identified the highest strike per nut-cracking episode, and for this strike, we calculated the height to which the monkey lifted the stone, the maximum velocity of the stone during the downward phase, the work done on the stone, and the kinetic energy of the strike. We found that individual capuchins achieved average maximum kinetic energy of 8.7-16.1 J when using stones between 0.9 and 1.9 kg, and maximum kinetic energy correlated positively with mass of the stone. Monkeys lifted all the stones to an individually consistent maximum height but added more work to the stone when using lighter stones. One male and one female monkey lifted stones higher when they cracked more resistant nuts. The high resistance of the Orbygnia nut elicits production of maximum kinetic energy, which the monkeys modulate to some degree by adding work to lighter stones. Capuchin monkeys, like chimpanzees, modulate their actions in nut-cracking, indicating skilled action, although neither species regulates kinetic energy as precisely as skilled human stone knappers. Kinematic analyses promise to yield new insights into the ways and extent to which nonhuman tool users develop expertise. Am J Phys Anthropol 161:53-61, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Kidney Stones in Primary Hyperoxaluria: New Lessons Learnt

PubMed Central

Jacob, Dorrit E.; Grohe, Bernd; Geßner, Michaela; Beck, Bodo B.; Hoppe, Bernd

2013-01-01

To investigate potential differences in stone composition with regard to the type of Primary Hyperoxaluria (PH), and in relation to the patient’s medical therapy (treatment naïve patients versus those on preventive medication) we examined twelve kidney stones from ten PH I and six stones from four PH III patients. Unfortunately, no PH II stones were available for analysis. The study on this set of stones indicates a more diverse composition of PH stones than previously reported and a potential dynamic response of morphology and composition of calculi to treatment with crystallization inhibitors (citrate, magnesium) in PH I. Stones formed by PH I patients under treatment are more compact and consist predominantly of calcium-oxalate monohydrate (COM, whewellite), while calcium-oxalate dihydrate (COD, weddellite) is only rarely present. In contrast, the single stone available from a treatment naïve PH I patient as well as stones from PH III patients prior to and under treatment with alkali citrate contained a wide size range of aggregated COD crystals. No significant effects of the treatment were noted in PH III stones. In disagreement with findings from previous studies, stones from patients with primary hyperoxaluria did not exclusively consist of COM. Progressive replacement of COD by small COM crystals could be caused by prolonged stone growth and residence times in the urinary tract, eventually resulting in complete replacement of calcium-oxalate dihydrate by the monohydrate form. The noted difference to the naïve PH I stone may reflect a reduced growth rate in response to treatment. This pilot study highlights the importance of detailed stone diagnostics and could be of therapeutic relevance in calcium-oxalates urolithiasis, provided that the effects of treatment can be reproduced in subsequent larger studies. PMID:23940605

The impact of pelvicaliceal anatomy on the success of retrograde intrarenal surgery in patients with lower pole renal stones.

PubMed

Resorlu, Berkan; Oguz, Ural; Resorlu, Eylem Burcu; Oztuna, Derya; Unsal, Ali

2012-01-01

To evaluate the impact of pelvicaliceal anatomy on the success of retrograde intrarenal surgery (RIRS) for lower pole renal stones and determine which of these factors can be used to select patients who will benefit from RIRS. We evaluated 67 patients who underwent RIRS between 2009 and 2010 for isolated lower pole renal stones. The infundibular length (IL), infundibular width (IW), pelvicaliceal height (PCH), and infundibulopelvic angle (IPA) were measured by preoperative intravenous urogram. Success was defined as either complete clearance or clearance with insignificant residual fragments≤3 mm in size at 2-months follow-up. Mean IL was 26.7±7.9 and 28.2±5.3 mm, mean PCH was 20.7±6.6 and 23.2±4.9 mm in stone-free and non-stone-free patients, respectively. These were slightly larger in the non-stone-free group but not statistically significant (P=.140 and P=.072, respectively). Mean IW was 5.8±3.5 and 5.6±2.2 mm in stone-free and non-stone-free patients, respectively, which had no significant impact on the stone-free rate (P=.719). There were significant differences between the groups in terms of stone length (P=.001) and IPA (P=.003). The mean IPA was 49.37±11.83 and 37.61±13.22 mm in stone-free and non-stone-free patients, respectively. In addition to the influence of stone size, lower pole anatomy, especially IPA, has a significant impact on stone clearance for lower pole stones after RIRS. Copyright © 2012 Elsevier Inc. All rights reserved.

Renal geology (quantitative renal stone analysis) by 'Fourier transform infrared spectroscopy'.

PubMed

Singh, Iqbal

2008-01-01

To prospectively determine the precise stone composition (quantitative analysis) by using infrared spectroscopy in patients with urinary stone disease presenting to our clinic. To determine an ideal method for stone analysis suitable for use in a clinical setting. After routine and a detailed metabolic workup of all patients of urolithiasis, stone samples of 50 patients of urolithiasis satisfying the entry criteria were subjected to the Fourier transform infrared spectroscopic analysis after adequate sample homogenization at a single testing center. Calcium oxalate monohydrate and dihydrate stone mixture was most commonly encountered in 35 (71%) followed by calcium phosphate, carbonate apatite, magnesium ammonium hexahydrate and xanthine stones. Fourier transform infrared spectroscopy allows an accurate, reliable quantitative method of stone analysis. It also helps in maintaining a computerized large reference library. Knowledge of precise stone composition may allow the institution of appropriate prophylactic therapy despite the absence of any detectable metabolic abnormalities. This may prevent and or delay stone recurrence.

[Uroliths of cats in Switzerland from 2002 to 2009].

PubMed

Gerber, B; Brandenberger-Schenk, F; Rothenanger, E; Müller, C

2016-10-01

In this study data on composition of uroliths collected from cats and epidemiologic data of affected cats in Switzerland from 2002 to 2009 are summarised. Of 884 stones analysed 50% (n=441) were composed of calcium oxalate, 45% (n=398) of struvite, 3% (n=18) of ammonium urate, 1% (n=12) were mixed stones, 1% (n=9) were composed of silica, 3 stones were solidified blood, 2 consisted of cystine and 1of xanthine. 40% of the ureteral stones were composed of struvite. Domestic cats had significantly less calcium oxalate stones compared to British Shorthair or Persian cats. Cats with calcium oxalate stones were older and cats with struvite stones were younger than other affected cats. Female and male cats were equally affected with stones. Compared to studies from other countries, in Switzerland silica stones occurred more often and ureteral stones were more often composed of Struvite. The present study shows that occurrence and prevalence of urinary calculi of cats from Switzerland exhibited only slight differences to studies from other countries.

Wait-and-see policy versus cholecystectomy after endoscopic sphincterotomy for bile-duct stones in high-risk patients with co-existing gallbladder stones: a prospective randomised trial.

PubMed

Zargar, Showkat A; Mushtaq, Mosin; Beg, Mashkoor A; Javaid, Gul; Khan, Bashir A; Hassan, Rayhana; Kasana, Reyaz A; Tabassum, Sameena

2014-03-01

Endoscopic sphincterotomy (ES) is one of the most important advances in the treatment of common bile duct (CBD) stones. However, the use of ES to remove CBD stones in high-risk patients without cholecystectomy is still debatable. The aim of this study was to compare the efficacy of a wait-and-see policy versus cholecystectomy after ES for CBD stones in high-risk patients with co-existing cholelithiasis. A total of 162 patients after undergoing ES with the clearance of CBD stones were randomised after informed consent to cholecystectomy or conservative management of their gallbladder stones. The results indicated that cholecystectomy after ES for CBD stones significantly reduced the biliary complications in high-risk patients. Every patient who has both CBD stones and gallstones with significant co-morbid illnesses, after clearance of CBD stones by ES, should undergo early cholecystectomy. Copyright © 2014 Arab Journal of Gastroenterology. Published by Elsevier Ltd. All rights reserved.

Efficacy of combining flexible and rigid ureteroscopy for transurethral lithotripsy.

PubMed

Shigemura, Katsumi; Yasufuku, Tomihiko; Yamashita, Masuo; Arakawa, Soichi; Fujisawa, Masato

2010-08-23

Transurethral lithotripsy (TUL) is a common procedure in urology. However, controversy persists about how to deal with stones pushed up into kidney from the ureter during the procedure of TUL. This study investigated the efficacy of combining flexible ureteroscopy and rigid ureteroscopy for pushed-up stones into kidney during TUL. Fotry-one patients underwent TUL by a single surgeon from July 2007 to May 2009. Eight cases resulted in pushed-up stones during operation or involved existing kidney stones. We used a Zero-tip or Litho Catch Basket catheter and a flexible ureteroscope to carry these stones in kidney down into the ureter where the rigid ureteroscope could then reach and handle the stone for lithotripsy or being taken away. A Lithoclast system was used for lithotripsy. Five cases involved stones pushed up during surgery and 3 cases involved stones already in the kidney in detail. We pulled the stones down into the ureter in all cases and successfully completed lithotripsy or removed the stone, thus avoiding the performance of additional extracorporeal shock wave lithotripsy (ESWL). In conclusions, combined use of flexible ureteroscopy and rigid ureteroscopy for upper urinary tract stones pushed up into the kidney during TUL or renal stones could be useful for avoiding additional ESWL.

Nephrolithiasis: Molecular Mechanism of Renal Stone Formation and the Critical Role Played by Modulators

PubMed Central

Aggarwal, Kanu Priya; Narula, Shifa; Kakkar, Monica

2013-01-01

Urinary stone disease is an ailment that has afflicted human kind for many centuries. Nephrolithiasis is a significant clinical problem in everyday practice with a subsequent burden for the health system. Nephrolithiasis remains a chronic disease and our fundamental understanding of the pathogenesis of stones as well as their prevention and cure still remains rudimentary. Regardless of the fact that supersaturation of stone-forming salts in urine is essential, abundance of these salts by itself will not always result in stone formation. The pathogenesis of calcium oxalate stone formation is a multistep process and essentially includes nucleation, crystal growth, crystal aggregation, and crystal retention. Various substances in the body have an effect on one or more of the above stone-forming processes, thereby influencing a person's ability to promote or prevent stone formation. Promoters facilitate the stone formation while inhibitors prevent it. Besides low urine volume and low urine pH, high calcium, sodium, oxalate and urate are also known to promote calcium oxalate stone formation. Many inorganic (citrate, magnesium) and organic substances (nephrocalcin, urinary prothrombin fragment-1, osteopontin) are known to inhibit stone formation. This review presents a comprehensive account of the mechanism of renal stone formation and the role of inhibitors/promoters in calcium oxalate crystallisation. PMID:24151593

Diversity in Protein Profiles of Individual Calcium Oxalate Kidney Stones

PubMed Central

Okumura, Nobuaki; Tsujihata, Masao; Momohara, Chikahiro; Yoshioka, Iwao; Suto, Kouzou; Nonomura, Norio; Okuyama, Akihiko; Takao, Toshifumi

2013-01-01

Calcium oxalate kidney stones contain low amounts of proteins, some of which have been implicated in progression or prevention of kidney stone formation. To gain insights into the pathophysiology of urolithiasis, we have characterized protein components of calcium oxalate kidney stones by proteomic approaches. Proteins extracted from kidney stones showed highly heterogeneous migration patterns in gel electrophoresis as reported. This was likely to be mainly due to proteolytic degradation and protein-protein crosslinking of Tamm-Horsfall protein and prothrombin. Protein profiles of calcium oxalate kidney stones were obtained by in-solution protease digestion followed by nanoLC-MALDI-tandem mass spectrometry, which resulted in identification of a total of 92 proteins in stones from 9 urolithiasis patients. Further analysis showed that protein species and their relative amounts were highly variable among individual stones. Although proteins such as prothrombin, osteopontin, calgranulin A and calgranulin B were found in most stones tested, some samples had high contents of prothrombin and osteopontin, while others had high contents of calgranulins. In addition, calgranulin-rich stones had various neutrophil-enriched proteins such as myeloperoxidase and lactotransferrin. These proteomic profiles of individual kidney stones suggest that multiple systems composed of different groups of proteins including leucocyte-derived ones are differently involved in pathogenesis of individual kidney stones depending on situations. PMID:23874695

Metabolic syndrome: a multifaceted risk factor for kidney stones.

PubMed

Domingos, Fernando; Serra, Adelaide

2014-10-01

Kidney stones and metabolic syndrome (MetS) are common conditions in industrialized countries. There is growing evidence of associations between kidney stone disease and MetS or some of its components. The link between uric acid stones and MetS is well understood, but the link with calcium oxalate (CaOx) stones, the most common kidney stone composition, is more complex, and MetS is frequently overlooked as a risk factor for calcium nephrolithiasis. The physiopathological mechanisms of kidney stone disease in MetS are reviewed in this article. Uric acid stones are a consequence of the excessively acidic urine that results from insulin resistance. The pathophysiology of CaOx stones may include: increased excretion of lithogenesis promoters and decreased excretion of inhibitors; increased risk of Randall's plaque development; and inflammatory damage to renal epithelia by oxidative stress, as a consequence of the insulin-resistant milieu that characterizes MetS. The last mechanism contributes to the adhesion of CaOx crystals to subepithelial calcium deposits working as anchor sites where stones can grow. The predominant MetS features could determine the chemical composition of the stones in each patient. Kidney stones may be a renal manifestation of MetS and features of this syndrome should be looked for in patients with idiopathic nephrolithiasis.

Stone orientation affects the mechanism of failure in artificial kidney stones subject to shock waves

NASA Astrophysics Data System (ADS)

van Cauwelaert, Javier; Cleveland, Robin O.

2003-10-01

Micro computed tomography (CT) imaging was used to follow the progressive development of cracks in artificial kidney stones. The artificial stones were made from U30 cement with a cylindrical shape (6.5 mm diameter and 8.5 mm long). The stones were held within a polypropylene vial in one of three orientations: vertical, horizontal, and angled at 45 deg. The stones were treated with an electromagnetic lithotripter and the initiation and growth of cracks was observed using microCT. The images show that the orientation of the stones with respect to the shock changes the dominant mechanism for fragmentation. Vertical stones developed a spall-like crack near the distal surface, which propagated from the surface to the interior of the stone. Initiation of a secondary spall-like crack was observed proximal to the first crack. Little surface damage was observed. Horizontal stones presented pitting in the proximal surface and erosion in lateral faces, indicating the action of cavitation. Angled stones presented both spall-like fracture in either the leading or the distal corners and surface damage (pitting) in the proximal surface. Experiments are being performed to follow the development of cracks in human kidney stones. [Work supported by the Whitaker Foundation.

Changes in urinary stone composition in the Tunisian population: a retrospective study of 1,301 cases.

PubMed

Alaya, Akram; Nouri, Abdellatif; Belgith, Mohsen; Saad, Hammadi; Jouini, Riadh; Najjar, Mohamed Fadhel

2012-05-01

Studies that evaluate the effect of age on stone composition are scarce. The aim of this study was to highlight the changes in epidemiological characteristics (stone composition and location) of urolithiasis according to patients' age. We studied 1,301 urolithiasis patients with age ranging from 6 months to 92 yr (781 males and 520 females). Stone analysis was performed using a stereomicroscope and infrared spectroscopy to determine the morphological type and molecular composition of each stone. The annual average incidence of new stone formation was 31.7 per 100,000 persons. In 71.8% of cases, calculi were located in the upper urinary tract. Compared to other age groups, children and old men were more affected by bladder stones. Calcium oxalate monohydrate was the most frequent stone component, even though its frequency decreased with age (59.5% in young adults and 43.7% in the elderly, P<0.05) in favor of an increase in uric acid stones (11.5% in young adults and 36.4% in the elderly, P<0.05). Struvite stones were rare (3.8%) and more frequent in children than in adults. The analysis of these data showed that urinary stones in Tunisian patients are tending to evolve in the same direction as the stones in patients from industrialized countries.

Impaction and Prediction: Does Ureteral Wall Thickness Affect the Success of Medical Expulsive Therapy in Pediatric Ureteral Stones?

PubMed

Tuerxun, Aierken; Batuer, Abudukahaer; Erturhan, Sakip; Eryildirim, Bilal; Camur, Emre; Sarica, Kemal

2017-01-01

The study aimed to evaluate the predictive value of ureteral wall thickness (UWT) and stone-related parameters for medical expulsive therapy (MET) success with an alpha blocker in pediatric upper ureteral stones. A total of 35 children receiving MET ureteral stones (<10 mm) were evaluated. Patients were divided into 2 subgroups where MET was successful in 18 children (51.4%) and unsuccessful in 17 children (48.6%). Prior to management, stone size, stone density (in Hounsfield unit), degree of hydronephrosis, and UWT were evaluated with patient demographics and recorded. The possible predictive value of these parameters in success rates and time to stone expulsion were evaluated in a comparative manner between the 2 groups. The overall mean patient age and stone size values were 5.40 ± 0.51 years and 6.24 ± 0.28 mm, respectively. Regarding the predictive values of these parameters for the success of MET, while stone size and UWT were found to be highly predictive for MET success, patients age, body mass index, stone density, and degree of hydronephrosis had no predictive value on this aspect. Our findings indicated that some stone and anatomical factors may be used to predict the success of MET in pediatric ureteral stones in an effective manner. With this approach, unnecessary use of these drugs that may cause a delay in removing the stone will be avoided, and the possible adverse effects of obstruction as well as stone-related clinical symptoms could be minimized. © 2017 S. Karger AG, Basel.

First in Human Clinical Trial of Ultrasonic Propulsion of Kidney Stones.

PubMed

Harper, Jonathan D; Cunitz, Bryan W; Dunmire, Barbrina; Lee, Franklin C; Sorensen, Mathew D; Hsi, Ryan S; Thiel, Jeff; Wessells, Hunter; Lingeman, James E; Bailey, Michael R

2016-04-01

Ultrasonic propulsion is a new technology using focused ultrasound energy applied transcutaneously to reposition kidney stones. We report what are to our knowledge the findings from the first human investigational trial of ultrasonic propulsion toward the applications of expelling small stones and dislodging large obstructing stones. Subjects underwent ultrasonic propulsion while awake without sedation in clinic, or during ureteroscopy while anesthetized. Ultrasound and a pain questionnaire were completed before, during and after propulsion. The primary outcome was to reposition stones in the collecting system. Secondary outcomes included safety, controllable movement of stones and movement of stones less than 5 mm and 5 mm or greater. Adverse events were assessed weekly for 3 weeks. Kidney stones were repositioned in 14 of 15 subjects. Of the 43 targets 28 (65%) showed some level of movement while 13 (30%) were displaced greater than 3 mm to a new location. Discomfort during the procedure was rare, mild, brief and self-limited. Stones were moved in a controlled direction with more than 30 fragments passed by 4 of the 6 subjects who had previously undergone a lithotripsy procedure. The largest stone moved was 10 mm. One patient experienced pain relief during treatment of a large stone at the ureteropelvic junction. In 4 subjects a seemingly large stone was determined to be a cluster of small passable stones after they were moved. Ultrasonic propulsion was able to successfully reposition stones and facilitate the passage of fragments in humans. No adverse events were associated with the investigational procedure. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Inaccurate reporting of mineral composition by commercial stone analysis laboratories: implications for infection and metabolic stones.

PubMed

Krambeck, Amy E; Khan, Naseem F; Jackson, Molly E; Lingeman, James E; McAteer, James A; Williams, James C

2010-10-01

We determined the accuracy of stone composition analysis at commercial laboratories. A total of 25 human renal stones with infrared spectroscopy determined composition were fragmented into aliquots and studied with micro computerized tomography to ensure fragment similarity. Representative fragments of each stone were submitted to 5 commercial stone laboratories for blinded analysis. All laboratories agreed on the composition of 6 pure stones. Only 2 of 4 stones (50%) known to contain struvite were identified as struvite at all laboratories. Struvite was reported as a component by some laboratories for 4 stones previously determined not to contain struvite. Overall there was disagreement regarding struvite in 6 stones (24%). For 9 calcium oxalate stones all laboratories reported some mixture of calcium oxalate but the quantity of subtypes differed significantly among laboratories. In 6 apatite containing stones apatite was missed by the laboratories in 20% of samples. None of the laboratories identified atazanavir in a stone containing that antiviral drug. One laboratory reported protein in every sample while all others reported it in only 1. Nomenclature for apatite differed among laboratories with 1 reporting apatite as carbonate apatite and never hydroxyapatite, another never reporting carbonate apatite and always reporting hydroxyapatite, and a third reporting carbonate apatite as apatite with calcium carbonate. Commercial laboratories reliably recognize pure calculi. However, variability in the reporting of mixed calculi suggests a problem with the accuracy of stone analysis results. There is also a lack of standard nomenclature used by laboratories. Copyright © 2010 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

INACCURATE REPORTING OF MINERAL COMPOSITION BY COMMERCIAL STONE ANALYSIS LABORATORIES: IMPLICATIONS FOR INFECTION AND METABOLIC STONES

PubMed Central

Krambeck, Amy E.; Khan, Naseem F.; Jackson, Molly E.; Lingeman, James E.; McAteer, James A; Williams, James C.

2011-01-01

INTRODUCTION The goal of this study was to determine the accuracy of stone composition analysis by commercial laboratories. METHODS 25 human renal stones with infrared spectroscopy (IR) determined compositions were fragmented into aliquots and studied with micro-computed tomography (CT) to ensure fragment similarity. Representative fragments of each stone were submitted to 5 commercial stone laboratories for blinded analysis. RESULTS All laboratories agreed on composition for 6 pure stones. Of 4 stones known to contain struvite, only 2(50%) were identified as struvite by all laboratories. Struvite was reported as a component by some laboratories for 4 stones previously determined not to contain struvite. Overall, there was disagreement regarding struvite in 6(24%) stones. For 9 calcium oxalate (CaOx) stones, all laboratories reported some mixture of CaOx, but the quantities of subtypes differed significantly among laboratories. In 6 apatite containing stones, apatite was missed by the laboratories in 20% of the samples. None of the laboratories identified atazanavir in a stone containing that antiviral drug. One laboratory reported protein in every sample, while all others reported it in only 1 sample. Nomenclature for apatite differed among laboratories, with one reporting apatite as carbonate apatite (CA) and never hydroxyapatite (HA), another never reporting CA and always reporting HA, and a third reporting CA as apatite with calcium carbonate. CONCLUSIONS Commercial laboratories reliably recognize pure calculi; however, variability in reporting of mixed calculi suggests a problem with accuracy of stone analysis results. Furthermore, there is a lack of standard nomenclature used by laboratories. PMID:20728108

Lessons from a Stone Farm

NASA Astrophysics Data System (ADS)

Kavanagh, John P.; Rao, P. Nagaraj

2007-04-01

The stone farm is a system for measuring macroscopic stone growth of 12 calcium stones simultaneously. It is based on mixed suspension, mixed product removal continuous crystallization principles and the stones are grown continuously for about 500 hours or more. The growth of the stones follows a surface area dependent pattern and the growth rate constants are very similar irrespective of whether the stating materials are fragments of human stone or pieces of marble chip. Increasing citrate from 2mM to 6mM caused a significant growth inhibition which persisted in the presence of urinary macromolecules. Phytate was a very effective inhibitor (about 50% at sub-μM concentrations) but the effective concentration was increased by an order of magnitude in the presence of urinary macromolecules. The effective concentration for inhibition in a crystallization assay was a further two orders of magnitude higher. Urinary macromolecules or almost whole urine were also strongly inhibitory although neither human serum albumin nor bovine mucin had any great effect. The relationship between the size distribution of crystals in suspension and the stone enlargement rate suggests that the primary enlargement mechanism for these in vitro stones is through aggregation. The stone farm is a powerful tool with which to study crystallization inhibitors in a new light. Some differences between inhibition of crystallization and inhibition of stone growth have emerged and we have obtained quantitative evidence on the mechanism of stone enlargement in vitro. Our findings suggest that the interface between crystals in suspension and the stone surface is the key to controlling stone enlargement.

Urinary Tract Stones and Osteoporosis: Findings From the Women's Health Initiative.

PubMed

Carbone, Laura D; Hovey, Kathleen M; Andrews, Christopher A; Thomas, Fridtjof; Sorensen, Mathew D; Crandall, Carolyn J; Watts, Nelson B; Bethel, Monique; Johnson, Karen C

2015-11-01

Kidney and bladder stones (urinary tract stones) and osteoporosis are prevalent, serious conditions for postmenopausal women. Men with kidney stones are at increased risk of osteoporosis; however, the relationship of urinary tract stones to osteoporosis in postmenopausal women has not been established. The purpose of this study was to determine whether urinary tract stones are an independent risk factor for changes in bone mineral density (BMD) and incident fractures in women in the Women's Health Initiative (WHI). Data were obtained from 150,689 women in the Observational Study and Clinical Trials of the WHI with information on urinary tract stones status: 9856 of these women reported urinary tract stones at baseline and/or incident urinary tract stones during follow-up. Cox regression models were used to determine the association of urinary tract stones with incident fractures and linear mixed models were used to investigate the relationship of urinary tract stones with changes in BMD that occurred during WHI. Follow-up was over an average of 8 years. Models were adjusted for demographic and clinical factors, medication use, and dietary histories. In unadjusted models there was a significant association of urinary tract stones with incident total fractures (HR 1.10; 95% CI, 1.04 to 1.17). However, in covariate adjusted analyses, urinary tract stones were not significantly related to changes in BMD at any skeletal site or to incident fractures. In conclusion, urinary tract stones in postmenopausal women are not an independent risk factor for osteoporosis. © 2015 American Society for Bone and Mineral Research.

The clinical research office of the endourological society percutaneous nephrolithotomy global study: staghorn versus nonstaghorn stones.

PubMed

Desai, Mahesh; De Lisa, Antonello; Turna, Burak; Rioja, Jorge; Walfridsson, Helena; D'Addessi, Alessandro; Wong, Carson; Rosette On Behalf Of The Croes Pcnl Study Group, Jean

2011-08-01

The study compared characteristics and outcomes in patients with staghorn or nonstaghorn stones who were treated with percutaneous nephrolithotomy (PCNL) within the Clinical Research Office of the Endourological Society (CROES) PCNL Global Study. Data over a 1-year period from consecutively treated patients from 96 centers worldwide were collated. The following variables in patients with staghorn or nonstaghorn stones were compared: National prevalence, patient characteristics, access method, puncture frequency and outcomes, including bleeding rates, operative time, and duration of hospital stay. Data from 5335 eligible patients were collated; 1466 (27.5%) with staghorn and 3869 (72.5%) with nonstaghorn stones. Staghorn stone presentation varied between centers from 67% in Thailand to 13% in Argentina. The frequencies of previous procedures were similar between groups, but shockwave lithotripsy was less frequent in patients with staghorn stones compared with nonstaghorn (16.8% vs 22.6%) and positive preoperative urine cultures were more frequent in patients with staghorn than nonstaghorn stones (23.4% vs 13.1%). Patients with staghorn stones underwent multiple punctures more frequently than those with nonstaghorn stones (16.9% vs 5.0%). Postoperative fever, bleeding, and the need for blood transfusion were more frequent, the median operative time and duration of hospital stay were longer, while the proportion of patients remaining stone free was lower (56.9% vs 82.5%) in patients with staghorn than nonstaghorn stones. The proportion of patients with staghorn stones varies widely between centers. Stone-free rates were lower, complications more frequent, and operative time and hospital stay were longer in patients with staghorn stones.

Natural History of Conservatively Managed Ureteral Stones: Analysis of 6600 Patients.

PubMed

Yallappa, Sachin; Amer, Tarik; Jones, Patrick; Greco, Francesco; Tailly, Thomas; Somani, Bhaskar K; Umez-Eronini, Nkem; Aboumarzouk, Omar M

2018-05-01

Ureteral colic has a lifetime prevalence of 10%-15% and is one of the most common emergency urologic presentations. Current European Association of Urology recommends conservative management for "small" (<6 mm) ureteral stones if active removal is not indicated. It is important to understand the natural history of ureteral stone disease to help counsel patients with regard to their likelihood of stone passage and anticipated time frame with which they could be safely observed. We aimed to conduct a systematic review to better establish the natural history of stone expulsion. Literature search was performed using Cochrane and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. Outcome measures were patient and stone demographics, expulsion rates, expulsion times, and side effect of the medication. A cumulative analysis, with subgroup analysis, was performed on stone location and size. The results were depicted as percentages and an intention-to-treat basis was used. The literature search identified 70 studies and a total of 6642 patients, with a median age of 46 and range of 18-74 years. Overall, 64% of patients successfully passed their stones spontaneously. About 49% of upper ureteral stones, 58% of midureteral stones, and 68% of distal ureteral stones passed spontaneously. Almost 75% of stones <5 mm and 62% of stones ≥5 mm passed spontaneously. The average time to stone expulsion was about 17 days (range 6-29 days). Nearly 5% of participants required rehospitalization due to a deterioration of their condition and only about 1% of patients experienced side effects from analgesia provided. We believe this current review is the largest study for the evaluation of natural history of ureteral stones. The evidence suggests that ureteral stones will pass without intervention in 64% of patients, however, this varies from nearly 50%-75% depending on the size and location, in the span of 1-4 weeks.

Protecting Space Travelers from Kidney Stones: Renal Stone Risk During Space Flight

NASA Technical Reports Server (NTRS)

Whitson, Peggy; Bloomberg, Jacob; Lee, Angie (Technical Monitor)

2002-01-01

Renal stones, popularly known as kidney or bladder stones, are small rock-like objects formed in the kidneys or urinary tract by deposits of calcium and other minerals. The problem arises when the stones block the drainage of the kidney, resulting in urinary obstruction and pain. Passing these stones can be one of the most painful experiences a person will endure so doctors often prescribe pain relievers to ease the experience. Drinking plenty of fluids, which help flush waste out of the body, and eating a well-balanced diet are the first steps to preventing stones. For individuals at risk, this may not be enough, and a doctor may recommend a special diet and medications. Unfortunately, approximately 60 percent of people who have had a renal stone will experience a recurrence. This is particularly true of men, who are four to five times more likely to develop stones than women. Renal stones do not discriminate based on age; even children are at risk. Astronauts are particularly at risk of developing renal stones because they lose bone and muscle mass; calcium, other minerals, and protein normally used for bone and muscle end up in the bloodstream and then in the kidneys. Without plenty of fluid to wash them away, crystals can form and then grow into stones. This factor compounds the risk for astronauts, since they also perceive that they are less thirsty in space and will drink less than normal during the mission. To minimize all of these factors, doctors must instead treat the stone-forming compounds with medication. This study will use potassium citrate to reduce the risk of stone formation. Renal stones are never convenient, but they are a particular concern for astronauts who have limited access to treatment during flight. Researchers are examining how earthbound preventions for renal stone formation work in flight, ensuring missions are not ended prematurely due to this medical condition. During STS-107, earthbound preventions and treatments become astronauts' gain.

A clinical nomogram to predict the successful shock wave lithotripsy of renal and ureteral calculi.

PubMed

Wiesenthal, Joshua D; Ghiculete, Daniela; Ray, A Andrew; Honey, R John D'A; Pace, Kenneth T

2011-08-01

Although shock wave lithotripsy is dependent on patient and stone related factors, there are few reliable algorithms predictive of its success. In this study we develop a comprehensive nomogram to predict renal and ureteral stone shock wave lithotripsy outcomes. During a 5-year period data from patients treated at our lithotripsy unit were reviewed. Analysis was restricted to patients with a solitary renal or ureteral calculus 20 mm or less. Demographic, stone, patient, treatment and 3-month followup data were collected from a prospective database. All patients were treated using the Philips Lithotron® lithotripter. A total of 422 patients (69.7% male) were analyzed. Mean stone size was 52.3±39.3 mm2 for ureteral stones and 78.9±77.3 mm2 for renal stones, with 95 (43.6%) of the renal stones located in the lower pole. The single treatment success rates for ureteral and renal stones were 60.3% and 70.2%, respectively. On univariate analysis predictors of shock wave lithotripsy success, regardless of stone location, were age (p=0.01), body mass index (p=0.01), stone size (p<0.01), mean stone density (p<0.01) and skin to stone distance (p<0.01). By multivariate logistic regression for renal calculi, age, stone area and skin to stone distance were significant predictors with an AUC of 0.75. For ureteral calculi predictive factors included body mass index and stone size (AUC 0.70). Patient and stone parameters have been identified to create a nomogram that predicts shock wave lithotripsy outcomes using the Lithotron lithotripter, which can facilitate optimal treatment based decisions and provide patients with more accurate single treatment success rates for shock wave lithotripsy tailored to patient specific situations. Copyright © 2011 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Study of stone composition changes in melamine-related urinary calculi and its clinical significance.

PubMed

Li, Yuan; Chen, YiRong; Zhang, Wei; Huang, XiaoGang; Li, WenHui; Ru, XiaoRui; Meng, Min; Xi, Xinsheng; Huang, Gang; Shi, BaoGuang; Liu, Gang; Li, WeiHua; Xu, Hui

2011-08-01

To investigate the composition changes in melamine-related urinary calculi and their clinical significance. A total of 49 melamine-related urinary calculi were included from 49 children (age 4-82 months, mean 22). The qualitative analysis of stone composition was determined using Fourier transform infrared. The quantitative analysis of the stone computed tomography (CT) attenuation value, stone uric acid level, and stone calcium level were measured using spiral CT, high-performance liquid chromatography, and flame atomic absorption spectrum, respectively. Fourier transform infrared showed that 41 (84%) of the 49 stones contained uric acid and 25 (51%) contained calcium compounds. The data from the qualitative and quantitative analysis were available for 15 stones because of sample consumption in the detection process (Fourier transform infrared, atomic absorption spectrum, and high-performance liquid chromatography). A negative correlation was observed between stone uric acid level and stone calcium level (n = 15, r = -0.629, P = .009). A positive correlation was observed between the stone calcium level and stone CT attenuation value (n = 25, r = 0.855, P = .000). Compared with the ≤1-year-age group and the 1-2-year-age group, the stone calcium level in the >2-year-age group was significantly greater (27.51% ± 12.65% vs 1.60% ± 1.68% or 10.12% ± 8.69%, P = .000 and P = .003, respectively). Compared with the alkalization-alone group, the stone calcium level in the nonalkalization-alone group was significant greater (19.83% ± 7.48% vs 1.25% ± 1.43%, n = 19, P = .000). The stones from children >2 years old were not amenable to medical treatment because they contained greater levels of calcium, which can be demonstrated by the radiologic "positive stone image" or stone CT attenuation value. We believe that surgical invention will be the best choice for such patients if extracorporeal shock wave lithotripsy has failed. Copyright © 2011 Elsevier Inc. All rights reserved.

Prevalence of kidney stones in the United States.

PubMed

Scales, Charles D; Smith, Alexandria C; Hanley, Janet M; Saigal, Christopher S

2012-07-01

The last nationally representative assessment of kidney stone prevalence in the United States occurred in 1994. After a 13-yr hiatus, the National Health and Nutrition Examination Survey (NHANES) reinitiated data collection regarding kidney stone history. Describe the current prevalence of stone disease in the United States, and identify factors associated with a history of kidney stones. A cross-sectional analysis of responses to the 2007-2010 NHANES (n=12 110). Self-reported history of kidney stones. Percent prevalence was calculated and multivariable models were used to identify factors associated with a history of kidney stones. The prevalence of kidney stones was 8.8% (95% confidence interval [CI], 8.1-9.5). Among men, the prevalence of stones was 10.6% (95% CI, 9.4-11.9), compared with 7.1% (95% CI, 6.4-7.8) among women. Kidney stones were more common among obese than normal-weight individuals (11.2% [95% CI, 10.0-12.3] compared with 6.1% [95% CI, 4.8-7.4], respectively; p<0.001). Black, non-Hispanic and Hispanic individuals were less likely to report a history of stone disease than were white, non-Hispanic individuals (black, non-Hispanic: odds ratio [OR]: 0.37 [95% CI, 0.28-0.49], p<0.001; Hispanic: OR: 0.60 [95% CI, 0.49-0.73], p<0.001). Obesity and diabetes were strongly associated with a history of kidney stones in multivariable models. The cross-sectional survey design limits causal inference regarding potential risk factors for kidney stones. Kidney stones affect approximately 1 in 11 people in the United States. These data represent a marked increase in stone disease compared with the NHANES III cohort, particularly in black, non-Hispanic and Hispanic individuals. Diet and lifestyle factors likely play an important role in the changing epidemiology of kidney stones. Published by Elsevier B.V.

Determining the composition of urinary tract calculi using stone-targeted dual-energy CT: evaluation of a low-dose scanning protocol in a clinical environment

PubMed Central

Chaytor, Richard J; Rajbabu, Krishnamoorthy; Jones, Paul A

2016-01-01

Objective: This study will evaluate the accuracy of dual-energy CT (DECT) in characterizing urinary tract stone composition on patients presenting to a UK hospital with renal colic. The study will also assess the additional radiation dose burden of DECT over standard protocol. Methods: Data from 106 DECTs between October 2011 and October 2015 were retrospectively analyzed. Patients were imaged using a Toshiba Aquilion ONE™ CT scanner (Toshiba Medical Systems, Otawara-shi, Japan). All patients received a low-dose non-contrast CT of the abdomen and pelvis prior to stone-targeted DECT at 80 and 135 kVp and 40-mm field of view. Radiation dose output was evaluated using dose–length product (DLP). 19 stones were recovered and their compositions were analyzed using Fourier transform infrared spectroscopy. Results: 137 stones were characterized. Mean stone diameter was 8.8 mm (range 3–48 mm). There was an 18.7% increase in mean DLP for DECT over standard CT protocol (319.4 vs 269.1 mGy cm; p < 0.001). Infrared spectroscopy analysis of 19 recovered stones identified 15 stones as calcium, 2 stones as cystine and 2 stones as mixed composition. Dual energy correctly predicted 11 (78.6%) of 14 calcium stones, 2 (100%) of 2 mixed composition stones and 0 (0%) of 2 cystine stones, resulting in a fair agreement (Cohen's κ = 0.374, p = 0.009). Conclusion: DECT is able to determine the composition of urinary tract stones with fair accuracy. Its utility is offset by a small but significant supplementary radiation exposure. Advances in knowledge: DECT can provide urological surgeons with useful diagnostic stone material information prior to planning optimal management of stone disease. PMID:27587309

Ureteroscopy

MedlinePlus

Ureteral stone surgery; Kidney stone - ureteroscopy; Ureteral stone removal - ureteroscopy; Calculi - ureteroscopy ... sent through the scope to grab and remove kidney stones or break them up using a laser. Place ...

Gender Distribution of Pediatric Stone Formers

NASA Astrophysics Data System (ADS)

Novak, Thomas E.; Trock, Bruce J.; Lakshmanan, Yegappan; Gearhart, John P.; Matlaga, Brian R.

2008-09-01

Recent epidemiologic evidence suggests that the gender prevalence among adult stone-formers is changing, with an increasing incidence of stone disease among women. No similar data have ever been reported for the pediatric stone-forming population. We performed a study to define the gender distribution among pediatric stone-formers using a large-scale national pediatric database. Our findings suggest that gender distribution among stone formers varies by age with male predominance in the first decade of life shifting to female predominance in the second decade. In contrast to adults, females in the pediatric population are more commonly affected by stones than are males. The incidence of pediatric stone disease appears to be increasing at a great rate in both sexes. Further studies should build on this hypothesis-generating work and define the effects of metabolic and environmental risk factors that may influence stone risk in the pediatric patient population

The sports science of curling: a practical review.

PubMed

Bradley, John L

2009-01-01

Curling is a sport played on ice in which two teams each deliver 8 granite stones towards a target, or 'house'. It is the only sport in which the trajectory of the projectile can be influenced after it has been released by the athlete. This is achieved by sweeping the ice in front of the stone to change the stone-ice friction and thereby enable to stone to travel further, curl more or stay straight. Hard sweeping is physically demanding. Different techniques of sweeping can also have different effects on the stone. This paper will review the current research behind sweeping a curling stone, outline the physiological demands of sweeping, the associated performance effects and suggest potential strategies of sweeping that can be used by both coaches and curling teams. Key pointsSweeping a curling stone can be highly physically demanding.Effective sweeping requires a combination of downward force and brush head speed, determined by the stone velocity.Sweeping on the left or right of a stone can help the stone to remain straight or curl more depending on the rotation of the stone.This can lead to the development of sweeping and playing tactics and contribute to team selection.

Evaluation of biochemical urinary stone composition and its relationship to tap water hardness in Qom province, central Iran

PubMed Central

Moslemi, Mohammad Kazem; Saghafi, Hossein; Joorabchin, Seyed Mohammad Amin

2011-01-01

Purpose The aim of this study was to evaluate the biochemical stone composition in general population of Qom province, central Iran, and its relationship with high tap water hardness. Materials and methods In a prospective study, from March 2008 to July 2011, biochemical analysis of urinary stones in patients living in Qom province for at least 5 years was performed. Stones were retrieved by spontaneous passage, endoscopic or open surgery, and after extracorporeal shockwave lithotripsy. Demographic findings and the drinking water supply of patients were evaluated and compared with biochemical stone analysis. Results Stone analysis was performed in 255 patients. The most dominant composition of urinary stones was calcium oxalate (73%), followed by uric acid (24%), ammonium urate (2%), and cystine (1%). The peak incidence of urinary stone was in patients in their forties. Overall male to female ratio was 4.93:1. Conclusion The dominant stone composition in inhabitants of central Iran, where tap water hardness is high, was calcium oxalate stones. On the basis of this study, biochemical urinary stone composition of Qom does not differ from other regions of Iran with lower water hardness. PMID:22163171

The Sports Science of Curling: A Practical Review

PubMed Central

Bradley, John L.

2009-01-01

Curling is a sport played on ice in which two teams each deliver 8 granite stones towards a target, or ‘house’. It is the only sport in which the trajectory of the projectile can be influenced after it has been released by the athlete. This is achieved by sweeping the ice in front of the stone to change the stone-ice friction and thereby enable to stone to travel further, curl more or stay straight. Hard sweeping is physically demanding. Different techniques of sweeping can also have different effects on the stone. This paper will review the current research behind sweeping a curling stone, outline the physiological demands of sweeping, the associated performance effects and suggest potential strategies of sweeping that can be used by both coaches and curling teams. Key points Sweeping a curling stone can be highly physically demanding. Effective sweeping requires a combination of downward force and brush head speed, determined by the stone velocity. Sweeping on the left or right of a stone can help the stone to remain straight or curl more depending on the rotation of the stone. This can lead to the development of sweeping and playing tactics and contribute to team selection. PMID:24149588

Single energy micro CT SkyScan 1173 for the characterization of urinary stone

NASA Astrophysics Data System (ADS)

Fitri, L. A.; Asyana, V.; Ridwan, T.; Anwary, F.; Soekersi, H.; Latief, F. D. E.; Haryanto, F.

2016-08-01

A urinary stone is a solid piece of material produced from crystallization of excreted substances in the urine. Knowledge of the composition of urinary stones is essential to determine the suitable treatment for the patient. The aim of this research was to characterize urinary stones using single energy micro CT SkyScan 1173. Six human urinary stones were scanned in vitro using 80 kV in micro CT SkyScan 1173. The produced projection, images, were reconstructed using NRecon (in-house software from SkyScan). The images of urinary stones were analyzed using CT Analyser (CT An) to obtain information of the internal structure and the Hounsfield Unit (HU) value to determine the information regarding the composition of the urinary stones, respectively. The average HU values from certain region of interests in the same slice were compared with spectral curves of known materials from National Institute of Standards and Technology (NIST). From the analysis, the composition of the six scanned stones were obtained. Two stones are composed of cystine, two are composed of struvite, two other stones are composed of struvite+cystine. In conclusion, the single energy micro CT with 80 kV can be used identifying cystine and struvite urinary stone.

In vitro comparison of renal stone laser treatment using fragmentation and popcorn technique.

PubMed

Klaver, Paul; de Boorder, Tjeerd; Rem, Alex I; Lock, Tycho M T W; Noordmans, Herke Jan

2017-09-01

To study the effectiveness of two laser techniques clinically used to fragment renal stones: fragmenting technique (FT) and popcorn technique (PT). Phantom stones were placed in a test tube filled with water, mimicking a renal calyx model. A Holmium:YAG laser was used for fragmentation using both techniques. Four series of experiments were performed with two parameters: the technique (FT or PT) and the number of stones in the test tube (one or four). The mass decrease of the phantom stones was measured before, during, and after the experiment to quantify the effect of both techniques. Visualization of PT showed that the main effect of PT takes place, when the stone moves in front of the laser fiber and is subject to direct radiant exposure. Both FT and PT resulted in a decrease in stone weight; the mass decrease of the stones subjected to FT exceeded that of the stones subjected to PT, even with less laser energy applied. This difference in mass decrease was evident in both the experiments with one and four stones. PT was less effective in decreasing stone weight compared with FT. The FT is more effective regarding the applied energy than PT, even in a shorter time period and regardless of the number of stones. This study suggests that FT is to be preferred over PT, when stones are accessible by the laser fiber. Lasers Surg. Med. 49:698-704, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Effect of Stone Size and Composition on Ultrasonic Propulsion Ex Vivo.

PubMed

Janssen, Karmon M; Brand, Timothy C; Bailey, Michael R; Cunitz, Bryan W; Harper, Jonathan D; Sorensen, Mathew D; Dunmire, Barbrina

2018-01-01

To evaluate in more detail the effectiveness of a new designed more efficient ultrasonic propulsion for large stones and specific stone compositions in a tissue phantom model. In the first clinical trial of noninvasive ultrasonic propulsion, urinary stones of unknown compositions and sizes up to 10 mm were successfully repositioned. The study included 8- to 12-mm stones of 4 different primary compositions (calcium oxalate monohydrate, ammonium acid urate, calcium phosphate, and struvite) and a renal calyx phantom consisting of a 12 mm × 30 mm well in a 10-cm block of tissue-mimicking material. Primary outcome was the number of times a stone was expelled over 10 attempts, with ultrasonic propulsion burst duration varying from 0.5 seconds to 5 seconds. Overall success rate at expelling stones was 95%. All calcium oxalate monohydrate and ammonium acid urate stones were expelled 100% of the time. The largest stone (12 mm) became lodged within the 12-mm phantom calyx 25% of the time regardless of the burst duration. With the 0.5-second burst, there was insufficient energy to expel the heaviest stone (0.88 g), but there was sufficient energy at the longer burst durations. With a single burst, ultrasonic propulsion successfully moved most stones at least 3 cm and, regardless of size or composition, expelled them from the calyx. Ultrasonic propulsion is limited to the stones smaller than the calyceal space, and for each burst duration, related to maximum stone mass. Published by Elsevier Inc.

Effect of Stone Size and Composition on Ultrasonic Propulsion Ex Vivo

PubMed Central

Janssen, Karmon M.; Brand, Timothy C.; Bailey, Michael R.; Cunitz, Bryan W.; Harper, Jonathan D.; Sorensen, Mathew D.; Dunmire, Barbrina

2018-01-01

OBJECTIVE To evaluate in more detail the effectiveness of a new designed more efficient ultrasonic propulsion for large stones and specific stone compositions in a tissue phantom model. In the first clinical trial of noninvasive ultrasonic propulsion, urinary stones of unknown compositions and sizes up to 10 mm were successfully repositioned. MATERIALS AND METHODS The study included 8- to 12-mm stones of 4 different primary compositions (calcium oxalate monohydrate, ammonium acid urate, calcium phosphate, and struvite) and a renal calyx phantom consisting of a 12 mm × 30 mm well in a 10-cm block of tissue-mimicking material. Primary outcome was the number of times a stone was expelled over 10 attempts, with ultrasonic propulsion burst duration varying from 0.5 seconds to 5 seconds. RESULTS Overall success rate at expelling stones was 95%. All calcium oxalate monohydrate and ammonium acid urate stones were expelled 100% of the time. The largest stone (12 mm) became lodged within the 12-mm phantom calyx 25% of the time regardless of the burst duration. With the 0.5-second burst, there was insufficient energy to expel the heaviest stone (0.88 g), but there was sufficient energy at the longer burst durations. CONCLUSION With a single burst, ultrasonic propulsion successfully moved most stones at least 3 cm and, regardless of size or composition, expelled them from the calyx. Ultrasonic propulsion is limited to the stones smaller than the calyceal space, and for each burst duration, related to maximum stone mass. PMID:28964820

Percutaneous suprapubic stone extraction for posterior urethral stones in children: efficacy and safety.

PubMed

Safwat, Ahmed S; Hameed, Diaa A; Elgammal, Mohamed A; Abdelsalam, Yasser M; Abolyosr, Ahmad

2013-08-01

To evaluate the safety and efficacy of percutaneous suprapubic stone extraction (PSPSE) for pediatric posterior urethral stones. Between July 2007 and June 2010, 54 boys presenting with acute urinary retention due to posterior urethral stones underwent PSPSE. Patients were a mean age of 66.4 months (range, 8-180 months). The stone size was 0.7-1.9 cm. Patients were placed under general anesthesia, and a 7F urethroscope was used to pushback the stone to the bladder. A 3-mm suprapubic puncture with a scalpel was performed, followed by insertion of a straight narrow hemostat through the puncture aided with cystoscopic guidance. The stone was grasped with the hemostat in its narrowest diameter and was extracted percutaneously or crushed if friable. The suprapubic puncture was closed with a single 4-0 Vicryl (Ethicon) suture. Intact stone retrieval was achieved in 45 patients, and the stone was crushed into minute fragments in 9 patients. Intraperitoneal extravasation developed in 1 patient that required open surgical intervention. Mean operative time was 22 minutes. Patients were monitored for up to 17 months, with complete resolution of symptoms and stone clearance. PSPSE provides a minimally invasive approach for the extraction of urethral and bladder stones in the pediatric population. The use of a straight hemostat for suprapubic stone extraction or crushing is a good alternative to suprapubic tract dilation, with minimal morbidity. Copyright © 2013 Elsevier Inc. All rights reserved.

Journey of a cystinuric patient with a long-term follow-up from a medical stone clinic: necessity to be SaFER (stone and fragments entirely removed).

PubMed

Moore, Sacha L; Somani, Bhaskar K; Cook, Paul

2018-04-25

There is a lack of studies looking at the longitudinal follow-up of patients with cystine stones. We wanted to assess the journey of cystinuric patients through our specialist metabolic stone clinic to improve the understanding of episodes, interventions and current outcomes in this patient cohort. After ethical approval, all patients who attended our metabolic stone clinic from 1994 to 2014 with at least one cystine stone episode were included in our study. Data were retrospectively analysed for patient demographics, stone episodes or intervention, clinical parameters and patient compliance. Over a period of 21 years, 16 patients with a median age of 15.5 years underwent a mean follow-up of 8.6 years (1-21 years). The mean number of surgical interventions was 3.1 (1-8/patient), but patients who were stone free after their first treatment had lower recurrences (p = 0.91) and lower number of interventions during their follow-up (2.7/patient, compared to those who were not stone free at 4/patient). During their follow-up period, patients with < 3 interventions had a significantly better renal function than those with ≥ 3 surgical interventions (p = 0.04). Additionally, linear regression analysis showed that eGFR was demonstrated to decline with increasing numbers of stone episodes (r 2  = 0.169). It was also noted that patients who began early medical management remained stone free during follow-up compared to those who had medical management after ≥ 2 stone episodes, of whom all had a recurrent episode. Our long-term longitudinal study of cystine stone formers highlights that patients who are stone free and receive early metabolic stone screening and medical management after their initial presentation have the lowest recurrence rates and tend to preserve their renal function. Hence, prompt referral for metabolic assessment, and the stone and fragments entirely removed (SaFER) principles are key to preventing stone episodes and improving long-term function.

A Prospective Evaluation of High-Resolution CT Parameters in Predicting Extracorporeal Shockwave Lithotripsy Success for Upper Urinary Tract Calculi.

PubMed

Abdelhamid, Mahmoud; Mosharafa, Ashraf A; Ibrahim, Hamdy; Selim, Hany M; Hamed, Mohamed; Elghoneimy, Mohamed N; Salem, Hosny K; Abdelazim, Mohamed S; Badawy, Hesham

2016-11-01

To evaluate the ability of noncontrast CT parameters (stone size, stone attenuation, and skin-to-stone distance [SSD]) to predict the outcome of extracorporeal shockwave lithotripsy (SWL) in a prospective cohort of patients with renal and upper ureteric stones. Patients with stones 5 to 20 mm were prospectively enrolled from 2011 to 2014. Patients had NCCT with recording of stone size, stone mean attenuation, and SSD, as well as various stone and patient parameters. The numbers of needed sessions as well as the final outcome were determined, with SWL failure defined as residual fragments >3 mm. Predictors of SWL failure were assessed by multiple regression analysis. Two hundred twenty patients (mean ± standard deviation [SD] age 41.5 ± 12.4 years) underwent SWL. Mean ± SD stone size was 11.3 ± 4.1 mm, while mean ± SD stone attenuation was 795.1 ± 340.4 HU. Mean ± SD SSD was 9.4 ± 2.1 cm. The average number of sessions was 1.64. SWL was effective in 186 (84.5%) patients (group A), while 34 (15.5%) patients had significant residual fragments (>3 mm). On univariate analysis, predictors of SWL failure included stone attenuation >1000 HU, older age, higher body mass index, higher attenuation value, larger stone size, and longer SSD. Increased SSD and higher stone attenuation retained their significance as independent predictors of SWL failure (p < 0.05) on multiple regression analysis both after first session and as final SWL outcome. A positive correlation was found between number of SWL sessions and mean stone attenuation (r = 0.6, p < 0.001) and SSD (r = 4, p < 0.001). Stone mean attenuation and SSD on noncontrast CT are significant independent predictors of SWL outcome in patients with renal and ureteric stones. These parameters should be included in clinical decision algorithms for patients with urolithiasis. For patients with stones having mean attenuation of >1000 HU and/or large SSDs, alternatives to SWL should be considered.

[Gallbladder Stone Types in Patients with Cholelithiasis and Clonorchis sinensis Infection in the Endemic Area of Clonorchiasis].

PubMed

Ma, Rui-hong; Qiao, Tie; Luo, Zhen-liang; Luo, Xiao-bing; Zheng, Pei-ming; Yang, Liu-qing

2015-06-01

To investigate the relationship between Clonorchis sinensis infection and the gallbladder stone type in patients with cholelithiasis in the endemic area of clonorchiasis. Gallbladder stones were collected from 598 patients with cholelithiasis through minimally invasive gallbladder-preserving cholelithotomy in the Sixth People's Hospital of Nansha District from May 2009 to October 2012. The stone samples were analyzed for composition by Fourier transform infrared spectroscopy to identify their types. The Clonorchis sinensis eggs were detected in the stones by microscopic examination, and the detection rates of eggs were calculated for different stone types. Then the clinical characteristics and biochemical indicators were compared among patients with different types of stones, as well as between Clonorchis sinensis egg-positive and -negative patients with the calcium-carbonate type of stones. Some calcium-carbonate stones positive for Clonorchis sinensis eggs were randomly selected for further scanning electron microscopy (SEM) examination. Of the stones from 598 patients, 234 (39.1%) were cholesterol type, 133 (22.2%) bile pigment type, 112(18.7%) calcium-carbonate type, 86 (14.4%) mixed types and 33(5.5%) were others. The detection rate of Clonorchis sinensis eggs in these types was 6% (15/234), 44% (59/133), 60% (67/112), 36% (31/ 86) and 30% (10/33), respectively, being highest in calcium-carbonate stones while lowest in cholesterol stones. The Co2-combining power of the plasma was higher in patients with calcium-carbonate and mixed stones than in those with cholesterol stones (P < 0.05), and the CO2-combining power of the bile and biliary pH were both higher in patients with calcium-carbonate types than in those with other types (P < 0.05). In addition, in patients with calcium-carbonate stones, the CO2-combining powers of the plasma and the bile, as well as biliary pH were all higher in the egg-positives than in the egg-negatives. Further, both light microscopy and SEM revealed adherence of the Clonorchis sinensis eggs to calcium-carbonate crystals. The infection rate of Clonorchis sinensis is higher in patients with calcium-carbonate gallbladder stones than in those with other types of stones.

COMPUTED TOMOGRAPHY VERSUS PLAIN RADIOGRAM IN EVALUATION OF RESIDUAL STONES AFTER PERCUTANEOUS NEPHROLITHOTOMY OR PYELONEPHROLITHOTOMY FOR COMPLEX MULTIPLE AND BRANCHED KIDNEY STONES.

PubMed

Wishahi, Mohamed; Elganzoury, Hossam; Elkhouly, Amr; Kamal, Ahmed M; Badawi, Mohamed; Eseaily, Khalid; Kotb, Samir; Morsy, Mohamed

2015-08-01

This study compared the efficacy of computed tomography of the urinary tract (CT urography) versus plain X-ray of the urinary tract (KUB) in detection and evaluation of the significance of residual stone after percutaneous nephrolithotripsy (PCNL) or surgical pyelonephrolithotomy (SPNL) for complex branching or multiple stones in the kidney. A retrospective prospective archival cohort of 168 patients underwent PCNL or SPNL for large stag horn or multiple stones in the kidney were evaluated, they were 113 patients who underwent SPNL, and 55 patients underwent PCNL. In all patients they had KUB second day of the operation, those who had multiple kidney punctures in the PCNL procedure for multiple stones, or multiple nephrotomies in the SPNL procedure, or had a radiolucent stones had an additional imaging with CT urography. Indications for the CT urography were cases of radiolucent stones and multiple small calyceal stones detected pre-operatively. The study was conducted between March 2010 and December 2014, data weie retrospectively analyzed. Preoperatively multiple or branching stones were diagnosed with intravenous urography and CT urography. Stone size and location were mapped pre-operatively on a real-size drawing, and three dimensional computed construction images in multiple planes. All patients were informed about the advantages, disadvantages and probable complications of both PCNL and SPNL before the selection of the procedure. Patients decided the type of the surgery type by themselves and written informed consent was obtained from all patients prior to the surgery. Patients were in two groups according to the patient's preference of surgery type. Group 1 consisted of 113 patients who underwent SPNL and Group 2 consisted of 55 patients treated with PCNL. Detection of residual stones stone postoperatively using KUB and CT urography was evaluated in both groups. There was statistical significance between the two imaging methodology in detection of residual stones after PCNL and/or SPNL. CT urography detected stones of 2 mm and up to 5mm which was not visualized with KUB. CT urography was statistically significant and precise in detecting the radiolucent stones of uric acid, urate, and phostate stones which were not detected by KUB.

46 CFR 56.15-1 - Pipe joining fittings.

Code of Federal Regulations, 2013 CFR

2013-10-01

... subpart 50.25 of this subchapter are acceptable for use in piping systems. (b) Threaded, flanged, socket-welding, buttwelding, and socket-brazing pipe joining fittings, made in accordance with the applicable...

46 CFR 56.15-1 - Pipe joining fittings.

Code of Federal Regulations, 2011 CFR

2011-10-01

... subpart 50.25 of this subchapter are acceptable for use in piping systems. (b) Threaded, flanged, socket-welding, buttwelding, and socket-brazing pipe joining fittings, made in accordance with the applicable...

46 CFR 56.15-1 - Pipe joining fittings.

Code of Federal Regulations, 2014 CFR

2014-10-01

... subpart 50.25 of this subchapter are acceptable for use in piping systems. (b) Threaded, flanged, socket-welding, buttwelding, and socket-brazing pipe joining fittings, made in accordance with the applicable...

46 CFR 56.15-1 - Pipe joining fittings.

Code of Federal Regulations, 2012 CFR

2012-10-01

... subpart 50.25 of this subchapter are acceptable for use in piping systems. (b) Threaded, flanged, socket-welding, buttwelding, and socket-brazing pipe joining fittings, made in accordance with the applicable...

Appendix D : FIB-54 tests.

DOT National Transportation Integrated Search

2013-03-01

Confinement reinforcement is placed near the end of pretensioned concrete I-girders to : enclose prestressing strands in the bottom flange. Experimental and analytical test programs : were conducted to investigate the function of confinement reinforc...

IGCP 637 Heritage Stone Designation: A UNESCO and IUGS project on natural stones

NASA Astrophysics Data System (ADS)

Pereira, Dolores; Cooper, Barry; Schouenborg, Björn; Marker, Brian; Kramar, Sabina

2017-04-01

IGCP 637 was approved in 2015 to facilitate establishment of a new international geological standard for building and ornamental stones. Formal international recognition of those natural stone types that have achieved widespread utilization in human culture is now underway and the term "Global Heritage Stone Resource" (GHSR) has been proposed for this designation. Stones that have been used in heritage construction, sculptural masterpieces, as well as in utilitarian (yet culturally important) applications are obvious GHSR candidates. In co-ordination with these aims the project has an associated role to promote the adoption and use of the GHSR designation. Consequently an interim list of potential GHSRs is maintained and a register of GHSR approved stones is being created. IGCP 637 also enhances the capacity of the International Union of Geological Sciences (IUGS) in the realm of dimension stone and geological standards as it is the first IUGS involvement in this subject. As a consequence, the largest known international grouping of dimension stone professionals has been established. Within IGCP 637 a web page has been created at www.globalheritagestone.com, including information on the Working Group and also specific information on the evolution of the project. Several researchers were funded to attend the Heritage Stone working group activities, including researchers from Algeria, Malawi, India, Italy and Russia. We also have produced many publications, both as individual papers and special issues in journals included in the Journal Citation Reports. Monographs are being prepared at present. Hopefully, IGCP 637 will help to widen the circle of researchers interested in natural stones as part of our geoheritage. Heritage Stone references: articles and special issues - Pereira, D. and Marker, B. (2016) The value of original natural stone in the context of architectural heritage. Geosciences, 6, 13. - Heritage Stone 1. Ed. Pereira and Pratt. (2016). Geoscience Canada, Series, vol. 43. - Global Heritage Stone Resource: An Update. Ed.: Pereira et al. (2015) Episodes, 38-2. - Global Heritage Stone: Towards International Recognition of Building and Ornamental Stones. Ed.: Pereira et al. (2015) Geological Society Special Publications, 407. - Pereira, D. and Baltuille, J.M. (2014) Documenting natural stone to preserve our cultural and architectonic heritage, Materiales de Construccion, 64 (314) - Engineering Geology for Society and Territory - Volume 5. Urban Geology, Sustainable Planning and Landscape Exploitation. Ed.: Lollino, G., et al. (2014). Springer International Publishing Switzerland.

Management of late biliary complications in patients with gallbladder stones in situ after endoscopic papillary balloon dilation.

PubMed

Tsujino, Takeshi; Kawabe, Takao; Isayama, Hiroyuki; Yashima, Yoko; Yagioka, Hiroshi; Kogure, Hirofumi; Sasaki, Takashi; Arizumi, Toshihiko; Togawa, Osamu; Ito, Yukiko; Matsubara, Saburo; Nakai, Yousuke; Sasashira, Naoki; Hirano, Kenji; Tada, Minoru; Omata, Masao

2009-04-01

Patients with untreated gallbladder stones in situ are at high risk for late biliary complications after endoscopic papillary balloon dilation (EPBD) and bile duct stone extraction. Few data exist on the short-term and long-term results in these patients after the recurrence of bile duct stones and acute cholecystitis. The aim of this study was to evaluate the outcome of late biliary complications in patients with gallbladder stones in situ after EPBD. Fifty-six patients who developed late biliary complications, including bile duct stone recurrence (n=43) and acute cholecystitis (n=13), were managed at our institutions. We investigated the short-term and long-term outcomes after the management of late biliary complications. Complete removal of recurrent bile duct stones was achieved in 38 of 43 patients (88%) by repeated EPBD alone. Pancreatitis after repeated EPBD occurred in two patients (5%). After successful bile duct stone extraction by EPBD, none of the 16 patients who underwent cholecystectomy developed late biliary complications (mean follow-up period of 5.2 years), wheras re-recurrent bile duct stones occurred in three of the 21 patients (14%) with gallbladder stones left in situ (mean follow-up period of 4.4 years)(P=0.1148). Re-recurrent bile duct stones were successfully treated endoscopically. One of the eight patients who did not undergo cholecystectomy for acute cholecystitis had a recurrence of cholecystitis, which was managed conservatively. The long-term outcomes of late biliary complications are favorable when patients with concomitant gallbladder stones undergo cholecystectomy. Re-recurrent bile duct stones are considerable when gallbladder stones are left in situ, but should be treated endoscopically.

Management of late biliary complications in patients with gallbladder stones in situ after endoscopic papillary balloon dilation.

PubMed

Tsujino, Takeshi; Kawabe, Takao; Isayama, Hiroyuki; Yashima, Yoko; Yagioka, Hiroshi; Kogure, Hirofumi; Sasaki, Takashi; Arizumi, Toshihiko; Togawa, Osamu; Ito, Yukiko; Matsubara, Saburo; Nakai, Yousuke; Sasashira, Naoki; Hirano, Kenji; Tada, Minoru; Omata, Masao

2009-04-01

Patients with untreated gallbladder stones in situ are at high risk for late biliary complications after endoscopic papillary balloon dilation (EPBD) and bile duct stone extraction. Few data exist on the short-term and long-term results in these patients after the recurrence of bile duct stones and acute cholecystitis. The aim of this study was to evaluate the outcome of late biliary complications in patients with gallbladder stones in situ after EPBD. Fifty-six patients who developed late biliary complications, including bile duct stone recurrence (n=43) and acute cholecystitis (n=13), were managed at our institutions. We investigated the short-term and long-term outcomes after the management of late biliary complications. Complete removal of recurrent bile duct stones was achieved in 38 of 43 patients (88%) by repeated EPBD alone. Pancreatitis after repeated EPBD occurred in two patients (5%). After successful bile duct stone extraction by EPBD, none of the 16 patients who underwent cholecystectomy developed late biliary complications (mean follow-up period of 5.2 years), whereas re-recurrent bile duct stones occurred in three of the 21 patients (14%) with gallbladder stones left in situ (mean follow-up period of 4.4 years)(P=0.1148). Re-recurrent bile duct stones were successfully treated endoscopically. One of the eight patients who did not undergo cholecystectomy for acute cholecystitis had a recurrence of cholecystitis, which was managed conservatively. The long-term outcomes of late biliary complications are favorable when patients with concomitant gallbladder stones undergo cholecystectomy. Re-recurrent bile duct stones are considerable when gallbladder stones are left in situ, but should be treated endoscopically.

Effects of Stone Size on the Comminution Process and Efficiency in Shock Wave Lithotripsy

PubMed Central

Zhang, Ying; Nault, Isaac; Mitran, Sorin; Iversen, Edwin S.; Zhong, Pei

2016-01-01

The effects of stone size on the process and comminution efficiency in shock wave lithotripsy (SWL) are investigated by experiments, numerical simulations, and scale analysis. Cylindrical BegoStone phantoms with approximately equal height and diameter of either 4-, or 7- or 10-mm, in a total aggregated mass of about 1.5 g, were treated in an electromagnetic shock wave lithotripter field. The resultant stone comminution (SC) was found to correlate closely with the average peak pressure, P+(avg), incident on the stones. The P+(avg) threshold to initiate stone fragmentation in water increased from 7.9 to 8.8 to 12.7 MPa, respectively, when the stone size decreased from 10 to 7 to 4 mm. Similar changes in the P+(avg) threshold were observed for the 7- and 10-mm stones treated in 1,3-butanediol where cavitation is suppressed, suggesting that the observed size dependency is due to changes in stress distribution within different size stones. Moreover, the slope of the correlation curve between SC and ln(P‒+(avg)) in water increased with decreasing stone size, while the opposite trend was observed in 1,3-butanediol. The progression of stone comminution in SWL showed a size-dependency with the 7- and 10-mm stones fragmented into progressively smaller pieces while a significant portion (> 30%) of the 4-mm stones were stalemated within the size range of 2.8 ~ 4 mm even after 1,000 shocks. Analytical scaling considerations suggest size-dependent fragmentation behaviour, a hypothesis further supported by numerical model calculations that exhibit changing patterns of constructive and destructive wave interference, and thus variations in the maximum tensile stress or stress integral produced in cylindrical and spherical stone of different sizes. PMID:27515177

The effect of climate variability on urinary stone attacks: increased incidence associated with temperature over 18 °C: a population-based study.

PubMed

Park, Hyoung Keun; Bae, Sang Rak; Kim, Satbyul E; Choi, Woo Suk; Paick, Sung Hyun; Ho, Kim; Kim, Hyeong Gon; Lho, Yong Soo

2015-02-01

The aim of this study was to evaluate the effect of seasonal variation and climate parameters on urinary tract stone attack and investigate whether stone attack is increased sharply at a specific point. Nationwide data of total urinary tract stone attack numbers per month between January 2006 and December 2010 were obtained from the Korean Health Insurance Review and Assessment Service. The effects of climatic factors on monthly urinary stone attack were assessed using auto-regressive integrated moving average (ARIMA) regression method. A total of 1,702,913 stone attack cases were identified. Mean monthly and monthly average daily urinary stone attack cases were 28,382 ± 2,760 and 933 ± 85, respectively. The stone attack showed seasonal trends of sharp incline in June, a peak plateau from July to September, and a sharp decline after September. The correlation analysis showed that ambient temperature (r = 0.557, p < 0.001) and relative humidity (r = 0.513, p < 0.001) were significantly associated with urinary stone attack cases. However, after adjustment for trends and seasonality, ambient temperature was the only climate factor associated with the stone attack cases in ARIMA regression test (p = 0.04). Threshold temperature was estimated as 18.4 °C. Risk of urinary stone attack significantly increases 1.71% (1.02-2.41 %, 95% confidence intervals) with a 1 °C increase of ambient temperature above the threshold point. In conclusion, monthly urinary stone attack cases were changed according to seasonal variation. Among the climates variables, only temperature had consistent association with stone attack and when the temperature is over 18.4 °C, urinary stone attack would be increased sharply.

Do Urinary Cystine Parameters Predict Clinical Stone Activity?

PubMed

Friedlander, Justin I; Antonelli, Jodi A; Canvasser, Noah E; Morgan, Monica S C; Mollengarden, Daniel; Best, Sara; Pearle, Margaret S

2018-02-01

An accurate urinary predictor of stone recurrence would be clinically advantageous for patients with cystinuria. A proprietary assay (Litholink, Chicago, Illinois) measures cystine capacity as a potentially more reliable estimate of stone forming propensity. The recommended capacity level to prevent stone formation, which is greater than 150 mg/l, has not been directly correlated with clinical stone activity. We investigated the relationship between urinary cystine parameters and clinical stone activity. We prospectively followed 48 patients with cystinuria using 24-hour urine collections and serial imaging, and recorded stone activity. We compared cystine urinary parameters at times of stone activity with those obtained during periods of stone quiescence. We then performed correlation and ROC analysis to evaluate the performance of cystine parameters to predict stone activity. During a median followup of 70.6 months (range 2.2 to 274.6) 85 stone events occurred which could be linked to a recent urine collection. Cystine capacity was significantly greater for quiescent urine than for stone event urine (mean ± SD 48 ± 107 vs -38 ± 163 mg/l, p <0.001). Cystine capacity significantly correlated inversely with stone activity (r = -0.29, p <0.001). Capacity also correlated highly negatively with supersaturation (r = -0.88, p <0.001) and concentration (r = -0.87, p <0.001). Using the suggested cutoff of greater than 150 mg/l had only 8.0% sensitivity to predict stone quiescence. Decreasing the cutoff to 90 mg/l or greater improved sensitivity to 25.2% while maintaining specificity at 90.9%. Our results suggest that the target for capacity should be lower than previously advised. Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Evaluating factors that dictate struvite stone composition: A multi-institutional clinical experience from the EDGE Research Consortium.

PubMed

Flannigan, Ryan K; Battison, Andrew; De, Shubha; Humphreys, Mitchell R; Bader, Markus; Lellig, Ekaterina; Monga, Manoj; Chew, Ben H; Lange, Dirk

2018-04-01

Struvite stones account for 15% of urinary calculi and are typically associated with urease-producing urinary tract infections and carry significant morbidity. This study aims to characterize struvite stones based on purity of stone composition, bacterial speciation, risk factors, and clinical features. Retrospective data was collected from patients diagnosed with infection stones between 2008 and 2012. Stone analysis, perioperative urine cultures, bacterial speciation, and clinical data were collected and analyzed. The purity of struvite stones was determined. Statistical comparisons were made among homogeneous and heterogeneous struvite stones. From the four participating centres, 121 struvite stones were identified. Only 13.2% (16/121) were homogenous struvite. Other components included calcium phosphate (42.1%), calcium oxalate (33.9%), calcium carbonate (27.3%), and uric acid (5.8%). Partial or full staghorn calculi occurred in 23.7% of cases. Urease-producing bacteria were only present in 30% of cases. Proteus, E. coli, and Enterococcus were the most common bacterial isolates from perioperative urine, and percutaneous nephrolithotomy was the most common modality of treatment. Only 40% of patients had a urinalysis that was nitrite-positive, indicating that urinalysis alone is not reliable for diagnosing infection stones. The study's limitation is its retrospective nature; as such, the optimal timing of cultures with respect to stone analysis or treatment was not always possible, urine cultures were often not congruent with stone cultures in the same patient, and our findings of E. coli commonly cultured does not suggest causation. Struvite stones are most often heterogeneous in composition. Proteus remains a common bacterial isolate; however, E. coli and Enterococcus were also frequently identified. This new data provides evidence that patients with struvite stones can have urinary tract pathogens other than urease-producing bacteria, thus challenging previous conventional dogma.

Evaluation of renal function in patients with a main renal stone larger than 1 cm and perioperative renal functional change in minimally invasive renal stone surgery: a prospective, observational study.

PubMed

Piao, Songzhe; Park, Juhyun; Son, Hwancheol; Jeong, Hyeon; Cho, Sung Yong

2016-05-01

To compare the perioperative relative renal function and determine predictors of deterioration and recovery of separate renal function in patients with renal stones >10 mm and who underwent mini-percutaneous nephrolithotomy or retrograde intra-renal surgery. A main stone >10 mm or stones growing, high-risk stone formers and extracorporeal shock-wave lithotripsy-resistant stones were prospectively included in 148 patients. Patients with bilateral renal stones and anatomical deformities were excluded. Renal function was evaluated by estimated glomerular filtration rate, 99m-technetium dimercaptosuccinic acid and 99m-technetium diethylenetriamine pentaacetate prior to intervention and at postoperative 3 months. Logistic regression analyses were performed to find predictors of functional deterioration and recovery. The overall stone-free rate was 85.1 %. A third of patients (53/148, 35.8 %) with renal stones >10 mm showed deterioration of separate renal function. Mean renal function of operative sites showed 58.2 % (36.8 %/63.2 %) of that of contralateral sites in these patients. Abnormal separate renal function showed postoperative recovery in 31 patients (58.5 %). Three cases (5.7 %) showed deterioration of separate renal function despite no presence of remnant stones. Improvement rates of the abnormal separate renal function did not differ according to the type of surgery. The presence of hydronephrosis and three or more stones were significant predictors for renal function deterioration. Female gender and three or more stones were significantly correlated with postoperative recovery. Mini-percutaneous nephrolithotomy or retrograde intra-renal surgery was effective and safe for renal function preservation. Patients with multiple large stones should be considered for candidates of active surgical removal.

Pattern of urinary tract stone diseases in Mekelle, Ethiopia.

PubMed

Alemu, Mekonnen Hagos

2008-07-01

To evaluate and analyze the pattern of patients with urinary stone diseases admitted to Mekelle Hospital. Between Sept 2003 to Sept 2006, 102 patients with urinary stone disease were admitted to Mekelle Hospital. In this descriptive retrospective audit, case notes were obtained from medical record office and were analyzed for age, sex, localization of the stone disease and the geographic back grounds. Seventy six (74.5%) of the patients were males and 26 (25.5%) were females. There were 102 (13.6%) cases of urinary stone disease admitted to Mekelle Hospital out of 750 total admissions for urological disease for intervention in the surgical ward during the study period. There were 76 (74.5%) males and 26 (25.5%) females and the sex ratio was (M: F: 2.9:1). Most (46.0%) of the urinary stone diseases were between 0-19 year age group both in males and females. The median age was 20 years (range from 2-74 years) and the mean was 25.4 years. Urinary bladder stones were the most common urinary tract stone diseases accounting for 47 (46.0%) followed by renal stones 29 (28.4%), ureteric 16 (15.6%) and urethral 10 (9.8%) stone disease; in that order of frequency. The geographical back ground of the patients with urinary tract stone disease in this report has shown that majorities (53.7%) were from urban and the remaining (44.2%) were from the rural areas. This study has depicted that urinary bladder stone diseases are the most common stone diseases affecting the younger age group. Since this is an institutional based study, it underestimates the magnitude and the pattern of urinary stone diseases at all level. Nevertheless, the audit provides useful information on the socio demographic variables, localization and the geographic back ground of the patients.

Interpreting the results of chemical stone analysis in the era of modern stone analysis techniques

PubMed Central

Gilad, Ron; Williams, James C.; Usman, Kalba D.; Holland, Ronen; Golan, Shay; Ruth, Tor; Lifshitz, David

2017-01-01

Introduction and Objective Stone analysis should be performed in all first-time stone formers. The preferred analytical procedures are Fourier-transform infrared spectroscopy (FT-IR) or X-ray diffraction (XRD). However, due to limited resources, chemical analysis (CA) is still in use throughout the world. The aim of the study was to compare FT-IR and CA in well matched stone specimens and characterize the pros and cons of CA. Methods In a prospective bi-center study, urinary stones were retrieved from 60 consecutive endoscopic procedures. In order to assure that identical stone samples were sent for analyses, the samples were analyzed initially by micro-computed tomography to assess uniformity of each specimen before submitted for FTIR and CA. Results Overall, the results of CA did not match with the FTIR results in 56% of the cases. In 16% of the cases CA missed the major stone component and in 40% the minor stone component. 37 of the 60 specimens contained CaOx as major component by FTIR, and CA reported major CaOx in 47/60, resulting in high sensitivity, but very poor specificity. CA was relatively accurate for UA and cystine. CA missed struvite and calcium phosphate as a major component in all cases. In mixed stones the sensitivity of CA for the minor component was poor, generally less than 50%. Conclusions Urinary stone analysis using CA provides only limited data that should be interpreted carefully. Urinary stone analysis using CA is likely to result in clinically significant errors in its assessment of stone composition. Although the monetary costs of CA are relatively modest, this method does not provide the level of analytical specificity required for proper management of patients with metabolic stones. PMID:26956131

Calcium Stone Growth in Urine from Cystic Fibrosis Patients and Healthy Controls

NASA Astrophysics Data System (ADS)

McSorley, Anita; Jones, Andrew M.; Webb, A. Kevin; Rao, P. Nagaraj; Kavanagh, John P.

2007-04-01

Cystic fibrosis patients have an increased risk of renal stone disease. There is some evidence that this may be related to a different excretory pattern of stone risk factors, but an alternative hypothesis, that the urine of cystic fibrosis patients is deficient in urinary inhibitors of crystallization and stone formation has not been tested. Here we have grown calcium stones, in vitro, in the presence of urine from healthy controls and compared this with growth in the presence of urine from cystic fibrosis patients. A stone farm was used to grow twelve calcium stones simultaneously, firstly in artificial urine for about 200 hours and then in 90% whole human urine for another 500 hours. Six of the stones received urine from healthy controls and six received urine from adult cystic fibrosis patients. There were no significant differences in stone mass at any of the key time points or in the overall growth pattern (p>0.05) between stones destined for, or treated with, urine from CF patients and the controls. Human urine greatly inhibited stone growth in vitro but there was no difference in the growth rate in urine from healthy controls and CF patients. This refutes the hypothesis that a tendency for a higher prevalence of urinary stones in CF patients is related to a deficiency in inhibitory activity.

Outcomes of Conservative Management of Asymptomatic Live Donor Kidney Stones.

PubMed

Sarier, Mehmet; Duman, Ibrahim; Callioglu, Mehmet; Soylu, Ahmet; Tekin, Sabri; Celep, Emrah; Turan, Hasan; Yavuz, Asuman Havva; Demirbas, Alper; Kukul, Erdal

2018-05-10

To evaluate the long-term outcomes of asymptomatic stones ≤4 mm which are left in situ during renal transplantation (RT). Between 2009 and 2017, 31 patients who received stone-bearing (≤4 mm) kidneys were analyzed. At their last follow-up, the patients were evaluated with CT imaging and the results were compared to the initial CT findings obtained during donor evaluation. The mean stone size was 2.9mm (range 1-4.3). The mean follow-up period after RT was 43.1 months (range 12-97). According to the CT findings of the last follow-up, the stone had passed spontaneously in 26(83.9%) patients. Three patients (9.6%) with a stone size of 4 mm required surgical intervention because the stone became symptomatic within the first year after transplantation. In the remaining 2 patients (6.4%), the stone remained in situ, without a change in its size. In terms of spontaneous passage rate, there was no significant difference between lower and mid-upper pole stones (p=0.948). De novo stone formation was observed in 2(6.4%) patients. Asymptomatic stones <4 mm which are detected on donor evaluation may safely be left in situ during RT. Regardless of their localization in the kidney, these stones have high spontaneous passage rates after RT, and the long-term recurrence rates are also considerably low. Copyright © 2018 Elsevier Inc. All rights reserved.

The surgical management of upper tract stone disease among spinal cord-injured patients.

PubMed

Welk, B; Shariff, S; Ordon, M; Catharine Craven, B; Herschorn, S; Garg, A X

2013-06-01

Retrospective cohort study, using linked, population-based health-care data. To describe the incidence, management and outcomes of surgically treated kidney stones after spinal cord injury (SCI). To evaluate the impact of a past history of kidney stones on the occurrence of kidney stones. Ontario, Canada. A total of 5121 patients were followed a median of 4 years after an incident SCI (occurring between 2002 and 2011). The primary outcome was surgical intervention for upper tract kidney stones. In follow-up, 66 patients (1.3%) had 89 episodes of surgically treated kidney stones. Treatments included: ureteroscopic lithotripsy (34%), ureteral stent/percutaneous nephrostomy (30%), shockwave lithotripsy (19%) or percutaneous nephrolithotripsy (17%). Following stone treatment, the 30-day mortality rate was low, and the 30-day admission rate to an intensive care unit was 12%. A history of surgically treated kidney stones before SCI (compared with no such history) was associated with a higher risk of kidney stones after SCI (27 vs 3 per 1000 person-years; adjusted hazard ratio 14.74, 95% confidence interval 5.69-38.22). During intermediate follow-up after SCI, surgically treated upper tract kidney stones occur in 1.3% of patients. Ureteroscopy with lithotripsy is the most common treatment. A history of surgically managed kidney stones before SCI portends a higher risk of stones after SCI.

Kidney stones: Composition, frequency and relation to metabolic diagnosis.

PubMed

Spivacow, Francisco R; Del Valle, Elisa E; Lores, Ernesto; Rey, Paula G

Nephrolithiasis is one of the most frequent urologic diseases. The aim of this paper is to study the composition and frequency of 8854 patient kidney stones and in a subset of them their metabolic risk factors to be related to their type of calculi. Physicochemical and crystallographic methods were used to assess kidney stone composition. In a subset of 715 patients, we performed an ambulatory metabolic protocol with diagnostic purposes. From the total sample 79% of stones were made of calcium salts (oxalate and phosphate), followed by uric acid stones in 16.5%, calcium salts and uric acid in 2%, other salts in 1.9% and cystine in 0.6%. Male to female ratio was almost three times higher in calcium salts and other types of stones, reaching a marked male predominance in uric acid stones, M/F 18.8 /1.0. The major risk factors for calcium stones are idiopathic hypercalciuria, followed by unduly acidic urine pH and hyperuricosuria. In uric acid stones unduly acidic urine pH and less commonly hyperuricosuria are the most frequent biochemical diagnosis. Our results show that analysis of kidney stones composition and the corresponding metabolic diagnosis may provide a scientific basis for the best management and prevention of kidney stone formation, as well as it may help us to study the mechanisms of urine stone formation.

Rapid vaporization of kidney stones, ex vivo, using a Thulium fiber laser at pulse rates up to 500 Hz with a stone basket

NASA Astrophysics Data System (ADS)

Hardy, Luke A.; Wilson, Christopher R.; Irby, Pierce B.; Fried, Nathaniel M.

2014-03-01

The Holmium:YAG laser (λ = 2120 nm) is currently the preferred laser for fragmenting kidney stones in the clinic. However, this laser has some limitations, including operation at low pulse rates and a multimode spatial beam profile which prohibits its use with smaller, more flexible optical fibers. Our laboratory is studying the Thulium fiber laser (λ = 1908 nm) as an alternative lithotripter. The TFL has several advantages, including lower stone ablation thresholds, use with smaller and more flexible fibers, and operation at arbitrary pulse lengths and pulse rates. Previous studies have reported increased stone ablation rates with TFL operation at higher pulse rates, however, stone retropulsion remains an obstacle to even more efficient stone ablation. This study explores TFL operation at high pulse rates in combination with a stone stabilization device (e.g. stone basket) for improved efficiency. A TFL beam with pulse energy of 35 mJ, pulse duration of 500-μs, and pulse rates of 10-500 Hz was coupled into 100-μm-core, low-OH, silica fibers, in contact mode with uric acid and calcium oxalate monohydrate stones, ex vivo. TFL operation at 500 Hz produced UA and COM stone ablation rates up to 5.0 mg/s and 1.3 mg/s, respectively. High TFL pulse rates produced increased stone ablation rates sufficient for use in the clinic.

Differentiation of uric acid versus non-uric acid kidney stones in the presence of iodine using dual-energy CT

NASA Astrophysics Data System (ADS)

Wang, J.; Qu, M.; Leng, S.; McCollough, C. H.

2010-04-01

In this study, the feasibility of differentiating uric acid from non-uric acid kidney stones in the presence of iodinated contrast material was evaluated using dual-energy CT (DECT). Iodine subtraction was accomplished with a commercial three material decomposition algorithm to create a virtual non-contrast (VNC) image set. VNC images were then used to segment stone regions from tissue background. The DE ratio of each stone was calculated using the CT images acquired at two different energies with DECT using the stone map generated from the VNC images. The performance of DE ratio-based stone differentiation was evaluated at five different iodine concentrations (21, 42, 63, 84 and 105 mg/ml). The DE ratio of stones in iodine solution was found larger than those obtained in non-iodine cases. This is mainly caused by the partial volume effect around the boundary between the stone and iodine solution. The overestimation of the DE ratio leads to substantial overlap between different stone types. To address the partial volume effect, an expectation-maximization (EM) approach was implemented to estimate the contribution of iodine and stone within each image pixel in their mixture area. The DE ratio of each stone was corrected to maximally remove the influence of iodine solutions. The separation of uric-acid and non-uric-acid stone was improved in the presence of iodine solution.

Metabolic stone composition in Egyptian children.

PubMed

Aggour, Ashraf; Ziada, Ali M; AbdelHamid, Ahmad Z; AbdelRahman, Sherif; Morsi, Ahmad

2009-04-01

The composition of urinary stones in children depends on socioeconomic conditions, geography and dietary habits. Pediatric urolithiasis remains endemic in developing countries. The aim of this study was to analyze stone composition in an Egyptian patient population. We analyzed prospectively urinary stones from 100 consecutive children (73 males, 27 females), aged 14 months to 12 years. The stones were located in the upper urinary tract in 78%, lower urinary tract in 19% and both in 3%. Male patients had more lower urinary tract stones. On presentation 67% had flank pain and 37% had hematuria. Stones were treated by open surgery in 69% of patients, shockwave lithotripsy in 20% and endoscopic extraction in 13%. The components of the upper urinary tract calculi were calcium oxalate (47%), ammonium acid urate (26%) and calcium carbonate (21%), whereas the main components of the lower urinary tract calculi were ammonium acid urate (27.2%), struvite (27.2%) and calcium carbonate (22.7%). Urinary tract infection was involved in the development of one third of the stones. Endemic stones were present in 17% of patients, and stones of metabolic origin in 15%. The etiology of stone formation remained unknown in one third of patients. The epidemiological profile of urinary stones in Egyptian children can now be considered intermediate between developing countries where dietary deficiencies are the main causes and developed countries where infectious and metabolic calculi are observed.

7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 5 2010-01-01 2010-01-01 false Domestic movements of earth (including soil), stone...; GENERAL; PLANT PESTS; SOIL, STONE, AND QUARRY PRODUCTS; GARBAGE Movement of Soil, Stone, And Quarry Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from...

7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 5 2012-01-01 2012-01-01 false Domestic movements of earth (including soil), stone...; GENERAL; PLANT PESTS; SOIL, STONE, AND QUARRY PRODUCTS; GARBAGE Movement of Soil, Stone, And Quarry Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from...

7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 5 2011-01-01 2011-01-01 false Domestic movements of earth (including soil), stone...; GENERAL; PLANT PESTS; SOIL, STONE, AND QUARRY PRODUCTS; GARBAGE Movement of Soil, Stone, And Quarry Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from...

7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 5 2014-01-01 2014-01-01 false Domestic movements of earth (including soil), stone...; GENERAL; PLANT PESTS; SOIL, STONE, AND QUARRY PRODUCTS; GARBAGE Movement of Soil, Stone, And Quarry Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from...

7 CFR 330.302 - Domestic movements of earth (including soil), stone, etc.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 5 2013-01-01 2013-01-01 false Domestic movements of earth (including soil), stone...; GENERAL; PLANT PESTS; SOIL, STONE, AND QUARRY PRODUCTS; GARBAGE Movement of Soil, Stone, And Quarry Products § 330.302 Domestic movements of earth (including soil), stone, etc. The interstate movement from...

Effect of Cystone® on urinary composition and stone formation over a one year period.

PubMed

Erickson, S B; Vrtiska, T J; Lieske, J C

2011-07-15

Kidney stones are a common problem for which inadequate prevention exists. We recruited ten recurrent kidney stone formers with documented calcium oxalate stones into a two phased study to assess safety and effectiveness of Cystone(®), an herbal treatment for prevention of kidney stones. The first phase was a randomized double-blinded 12 week cross over study assessing the effect of Cystone(®) vs. placebo on urinary supersaturation. The second phase was an open label one year study of Cystone(®) to determine if renal stone burden decreased, as assessed by quantitative and subjective assessment of CT. Results revealed no statistically significant effect of Cystone(®) on urinary composition short (6 weeks) or long (52 weeks) term. Average renal stone burden increased rather than decreased on Cystone(®). Therefore, this study does not support the efficacy of Cystone(®) to treat calcium oxalate stone formers. Future studies will be needed to assess effects on stone passage, or on other stone types. Copyright © 2011 Elsevier GmbH. All rights reserved.

Absence of bacterial imprints on struvite-containing kidney stones: a structural investigation at the mesoscopic and atomic scale.

PubMed

Bazin, Dominique; André, Gilles; Weil, Raphael; Matzen, Guy; Emmanuel, Veron; Carpentier, Xavier; Daudon, M

2012-04-01

Bacterial imprints are always observed on highly carbonated apatite kidney stones but not struvite kidney stones. Struvite and carbonated apatite stones with a high CO(3)(2-)/PO(4)(3-) rate are believed to develop from infections, but their structural differences at the mesoscopic scale lack explanation. We investigated 17 urinary calculi composed mainly of struvite or carbonated apatite by Fourier transform infrared, scanning electron microscopy, and powder neutron diffraction techniques. Carbonated apatite but not struvite stones showed bacterial imprints. If the same stone contained both carbonated apatite and struvite components, bacterial imprints were observed on the carbonated apatite but not the struvite part. Moreover, neutron powder diffraction experiments revealed the crystal size of struvite stones were larger than that of carbonated apatite stones (250 ± 50 vs 50 nm). Bacterial imprints may appear more easily on kidney stones with small nanocrystals, such as carbonated apatite than with large nanocrystals, such as struvite. This approach may help identify bacteria contributing to stone formation, perhaps with negative results of urine culture. Copyright © 2012 Elsevier Inc. All rights reserved.

What can the microstructure of stones tell us?

PubMed Central

Williams, James C.; Worcester, Elaine; Lingeman, James E.

2016-01-01

How stones are retained within the kidney while small in size is still not fully understood. In this paper we show two examples of how stones are retained during early growth: One is growth on Randall’s (interstitial) plaque, and the other is growth on mineral that has formed as a luminal plug in a terminal collecting duct. These two mechanisms of stone retention during early growth have distinctive morphologic features that can be seen by methods that show the microscopic structure of the stones. Stones growing on Randall’s plaque display an apatite region that is typically not large in size (less than 0.5 mm across) but which usually shows luminal spaces, which are signs of its origin in the connective tissue of the papilla. Stones growing on ductal plugs also show attachment to a piece of apatite, but the apatite regions are typically larger (often >1 mm long and >0.5 mm wide), and they are solid, without spaces running through them. We propose that knowing the mechanisms of stone retention during early stone formation could allow for better treatment of stone diseases. PMID:27913855

HOUSINGS AND MOUNTINGS FOR CENTRIFUGES

DOEpatents

Rushing, F.C.

1960-08-16

A protective housing for a gas centrifuge comprises a slidable connection between flanges and framework portions for absorbing rotational energy in case of bursting of the rotor and a sealing means for sealing the rotor chamber.

Appendix G : end region design models.

DOT National Transportation Integrated Search

2013-03-01

The 2007 AASHTO LRFD Bridge Design Specifications contain prescriptive : requirements for the quantity and placement of confinement reinforcement located in the bottom : flange of pretensioned concrete I-girders. This chapter proposes a rational mode...

46 CFR 61.20-17 - Examination intervals.

Code of Federal Regulations, 2010 CFR

2010-10-01

... corrosion by sea water, or fitted with a continuous liner or a sealing gland which prevents sea water from... stress concentrations or are fitted with a flanged propeller. Accessible portions of tailshafts must be...

40 CFR 265.192 - Design and installation of new tank systems or components.

Code of Federal Regulations, 2012 CFR

2012-07-01

... or sacrificial anodes); and (C) Electrical isolation devices such as insulating joints and flanges... stress due to settlement, vibration, expansion or contraction. Note: The piping system installation...

40 CFR 265.192 - Design and installation of new tank systems or components.

Code of Federal Regulations, 2014 CFR

2014-07-01

... or sacrificial anodes); and (C) Electrical isolation devices such as insulating joints and flanges... stress due to settlement, vibration, expansion or contraction. Note: The piping system installation...

40 CFR 265.192 - Design and installation of new tank systems or components.

Code of Federal Regulations, 2013 CFR

2013-07-01

... or sacrificial anodes); and (C) Electrical isolation devices such as insulating joints and flanges... stress due to settlement, vibration, expansion or contraction. Note: The piping system installation...

40 CFR 265.192 - Design and installation of new tank systems or components.

Code of Federal Regulations, 2011 CFR

2011-07-01

... or sacrificial anodes); and (C) Electrical isolation devices such as insulating joints and flanges... stress due to settlement, vibration, expansion or contraction. Note: The piping system installation...

49 CFR 393.67 - Liquid fuel tanks.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., by brazing, by silver soldering, or by techniques which provide heat resistance and mechanical... soldering with a lead-based or other soft solder. (2) Fittings. The fuel tank body must have flanges or...

49 CFR 393.67 - Liquid fuel tanks.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., by brazing, by silver soldering, or by techniques which provide heat resistance and mechanical... soldering with a lead-based or other soft solder. (2) Fittings. The fuel tank body must have flanges or...

49 CFR 393.67 - Liquid fuel tanks.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., by brazing, by silver soldering, or by techniques which provide heat resistance and mechanical... soldering with a lead-based or other soft solder. (2) Fittings. The fuel tank body must have flanges or...

49 CFR 393.67 - Liquid fuel tanks.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., by brazing, by silver soldering, or by techniques which provide heat resistance and mechanical... soldering with a lead-based or other soft solder. (2) Fittings. The fuel tank body must have flanges or...

49 CFR 180.515 - Markings.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Pressure converted tank cars must have the new specification and conversion date permanently marked in... the manway nozzle flange on the left side of the car. The marking may have the last numeral of the...

49 CFR 180.515 - Markings.

Code of Federal Regulations, 2010 CFR

2010-10-01

... date. (b) Pressure converted tank cars must have the new specification and conversion date permanently... the edge of the manway nozzle flange on the left side of the car. The marking may have the last...

Note: O-ring stack system for electron gun alignment

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

Park, In-Yong; Cho, Boklae; Han, Cheolsu

We present a reliable method for aligning an electron gun which consists of an electron source and lenses by controlling a stack of rubber O-rings in a vacuum condition. The beam direction angle is precisely tilted along two axes by adjusting the height difference of a stack of O-rings. In addition, the source position is shifted in each of three orthogonal directions. We show that the tilting angle and linear shift along the x and y axes as obtained from ten stacked O-rings are ±2.55° and ±2 mm, respectively. This study can easily be adapted to charged particle gun alignmentmore » and adjustments of the flange position in a vacuum, ensuring that its results can be useful with regard to electrical insulation between flanges with slight modifications.« less

Self-adjustable supplemental support system for a cylindrical container in a housing

DOEpatents

Blaushild, R.M.

1987-01-30

A self-adjustable supplementary support system for a cylindrical container coaxially disposed in a cylindrical housing by upper flanged supports has a plurality of outwardly extending bracket units on the external surface of the container which coact with inwardly extending resiliently outwardly extending bracket units on the inner wall of the cylindrical housing. The bracket units have flanges which form a concave surface that seats on support bars, attached by links to torsion bars that are secured to ring segments annularly spaced about the inner wall of the cylindrical housing and the bracket units and support bars coact with each other to radially position and support the container in the housing during movement of the two components from a vertical to a horizontal position, and during transportation of the same. 14 figs.