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Sample records for straightening

  1. Hair straightener poisoning

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/002706.htm Hair straightener poisoning To use the sharing features on this page, please enable JavaScript. Hair straightener poisoning occurs when someone swallows products that ...

  2. Hair straightener poisoning

    MedlinePlus

    ... relaxer/straightener products that do not use lye) Mineral oil Polyethylene glycol Sodium hydroxide (found in relaxer/ ... ed. Philadelphia, PA: Elsevier Saunders; 2007:chap 100. Wax PM, Young A. Caustics. In: Marx JA, Hockberger ...

  3. Holder for Straightening Bent Tubes

    NASA Technical Reports Server (NTRS)

    Turner, A. R.; Polzien, E. D.

    1985-01-01

    One-piece holder restrains bent metal tube against further bending during straightening operation. Holder consists of handle 16 in. (41 cm) long welded to short, strong tube that fits around tube to be straightened.

  4. Straightening: existence, uniqueness and stability

    PubMed Central

    Destrade, M.; Ogden, R. W.; Sgura, I.; Vergori, L.

    2014-01-01

    One of the least studied universal deformations of incompressible nonlinear elasticity, namely the straightening of a sector of a circular cylinder into a rectangular block, is revisited here and, in particular, issues of existence and stability are addressed. Particular attention is paid to the system of forces required to sustain the large static deformation, including by the application of end couples. The influence of geometric parameters and constitutive models on the appearance of wrinkles on the compressed face of the block is also studied. Different numerical methods for solving the incremental stability problem are compared and it is found that the impedance matrix method, based on the resolution of a matrix Riccati differential equation, is the more precise. PMID:24711723

  5. Guide for extrusion dies eliminates straightening operation

    NASA Technical Reports Server (NTRS)

    Gyorgak, C. A.; Hoover, R. J.

    1964-01-01

    To prevent distortion of extruded metal, a guidance assembly is aligned with the die. As the metal emerges from the extrusion dies, it passes directly into the receiver and straightening tube system, and the completed extrusion is withdrawn.

  6. 6. VIEW OF FIVEFOOT WIND TUNNEL WITH AIR STRAIGHTENER AND ...

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

    6. VIEW OF FIVE-FOOT WIND TUNNEL WITH AIR STRAIGHTENER AND OPERATOR STATION IN FOREGROUND (1991). - Wright-Patterson Air Force Base, Area B, Building No. 19, Five-Foot Wind Tunnel, Dayton, Montgomery County, OH

  7. 30 CFR 57.7011 - Straightening crossed cables.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... and Rotary Jet Piercing Drilling-Surface Only § 57.7011 Straightening crossed cables. The drill stem shall be resting on the bottom of the hole or on the platform with the stem secured to the mast...

  8. 30 CFR 56.7011 - Straightening crossed cables.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Rotary Jet Piercing Drilling § 56.7011 Straightening crossed cables. The drill stem shall be resting on the bottom of the hole or on the platform with the stem secured to the mast before attempts are...

  9. 30 CFR 57.7011 - Straightening crossed cables.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and Rotary Jet Piercing Drilling-Surface Only § 57.7011 Straightening crossed cables. The drill stem shall be resting on the bottom of the hole or on the platform with the stem secured to the mast...

  10. 18. VIEW OF ROLLER LEVELER USED TO STRAIGHTEN AND FLATTEN ...

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

    18. VIEW OF ROLLER LEVELER USED TO STRAIGHTEN AND FLATTEN METAL SHEETS. (7/2/86) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

  11. 30 CFR 56.7011 - Straightening crossed cables.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Rotary Jet Piercing Drilling § 56.7011 Straightening crossed cables. The drill stem shall be resting on the bottom of the hole or on the platform with the stem secured to the mast before attempts are...

  12. 30 CFR 56.7011 - Straightening crossed cables.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Rotary Jet Piercing Drilling § 56.7011 Straightening crossed cables. The drill stem shall be resting on the bottom of the hole or on the platform with the stem secured to the mast before attempts are...

  13. 30 CFR 57.7011 - Straightening crossed cables.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... and Rotary Jet Piercing Drilling-Surface Only § 57.7011 Straightening crossed cables. The drill stem shall be resting on the bottom of the hole or on the platform with the stem secured to the mast...

  14. 30 CFR 56.7011 - Straightening crossed cables.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Rotary Jet Piercing Drilling § 56.7011 Straightening crossed cables. The drill stem shall be resting on the bottom of the hole or on the platform with the stem secured to the mast before attempts are...

  15. 30 CFR 56.7011 - Straightening crossed cables.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Rotary Jet Piercing Drilling § 56.7011 Straightening crossed cables. The drill stem shall be resting on the bottom of the hole or on the platform with the stem secured to the mast before attempts are...

  16. 30 CFR 57.7011 - Straightening crossed cables.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... and Rotary Jet Piercing Drilling-Surface Only § 57.7011 Straightening crossed cables. The drill stem shall be resting on the bottom of the hole or on the platform with the stem secured to the mast...

  17. 30 CFR 57.7011 - Straightening crossed cables.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and Rotary Jet Piercing Drilling-Surface Only § 57.7011 Straightening crossed cables. The drill stem shall be resting on the bottom of the hole or on the platform with the stem secured to the mast...

  18. Flow Straightener for a Rotating-Drum Liquid Separator

    NASA Technical Reports Server (NTRS)

    O'Coin, James R.; Converse, David G.; Rethke, Donald W.

    2004-01-01

    A flow straightener has been incorporated into a rotary liquid separator that originally comprised an inlet tube, a shroud plate, an impeller, an inner drum, an outer drum, a housing, a pitot tube, and a hollow shaft motor. As a consequence of the original geometry of the impeller, shroud, inner drum, and hollow shaft, swirl was created in the airflow inside the hollow shaft during operation. The swirl speed was large enough to cause a significant pressure drop. The flow straightener consists of vanes on the back side of the shroud plate. These vanes compartmentalize the inside of the inner drum in such a way as to break up the flow path and thereby stop the air from swirling; as a result, the air enters the hollow shaft with a predominantly axial velocity instead of a swirl. Tests of the rotary liquid separator at an airflow rate of 10 cu ft/min (0.0047 cu m/s) revealed that the dynamic pressure drop was 8 in. of water (approx.=2 kPa) in the absence of the flow straightener and was reduced to 1 in. of water (approx.=0.25 kPa) in the presence of the flow straightener.

  19. Autonomic straightening of gravitropically curved cress roots in microgravity.

    PubMed

    Stankovic, B; Antonsen, F; Johnsson, A; Volkmann, D; Sack, F D

    2001-01-01

    The typical response of plant organs to gravistimulation is differential growth that leads to organ bending. If the gravitropic stimulus is withdrawn, endogenous compensation of the graviresponse and subsequent straightening occur in some plants. For instance, autonomic straightening of Lepidium roots occurs when gravitropically-curved rootsare rotated on a clinostat (Stankovi et al., 1998a). To determine whether endogenous compensation of the graviresponse also occurs in space, microgravity-grown cress roots were laterally centrifuged in-flight and then returned to microgravity using Biorack hardware on a shuttle mission (STS-81). The cress roots were centrifuged at 4 different g-doses (0.1 x g and 1 x g for 15 or 75 min). All four treatments yielded varying degrees of root curvature. Upon removal from the centrifuge, roots in all four treatments underwent subsequent straightening in microgravity. This straightening resulted from a loss of gravitropic curvature in older regions of the root and the coordinated alignment of new growth. These results show that both microgravity and clinostat rotation on Earth are equivalent in stimulus withdrawal with respect to the induction of endogenous compensation of the curvature. Cress roots are the only plant organ shown to undergo compensation of the curvature in both microgravity and on a clinostat. The compensation of graviresponse in space rules out the hypothesis that the endogenous root straightening ("autotropism") represents a commitment to a pre-stimulus orientation with respect to gravity and instead suggests that there is a default tendency towards axiality following a withdrawal of a g-stimulus. PMID:11594376

  20. Suspended, straightened carbon nanotube arrays by gel chapping.

    PubMed

    Ji, Chunyan; Li, Hongbian; Zhang, Luhui; Liu, Yu; Li, Yan; Jia, Yi; Li, Zhen; Li, Peixu; Shi, Enzheng; Wei, Jinquan; Wang, Kunlin; Zhu, Hongwei; Wu, Dehai; Cao, Anyuan

    2011-07-26

    We report large-scale self-assembly of suspended, straightened, single-walled carbon nanotubes (SWNTs) across regular TiO(2) gel islands. By coating a SWNT network on top of a pool of the TiO(2) colloid and inducing a rapid drying and chapping process, initially curled, random SWNTs can be straightened into aligned arrays and suspended across the island gaps. The suspended SWNT arrays were grafted by semiconducting or metallic nanoparticles, resulting in hybrid structures with tailored and neat morphology, and enhanced photoresponse. We further demonstrate these suspended SWNTs can sustain high speed gas blowing (up to 20 m per second) reversibly for hundreds of cycles, and detect gas velocity by the resistance change. PMID:21699200

  1. PROCESSING OF NANOSTRUCTURED COPPER BY REPETITIVE CORRUGATION AND STRAIGHTENING (RCS)

    SciTech Connect

    Zhu, Y.T.; Jiang, H.

    2000-10-01

    A new process, Repetitive Corrugation and Straightening (RCS), has been developed to create bulk, nanostructured copper. In this investigation, a high purity (99.99%). copper bar measuring 6 x 6 x 50 mm with an average grain size of 765 {micro}m was used as the starting material. It was repetitively corrugated and straightened for 14 times with 90{degree} rotations along its longitudinal axis between consecutive corrugation-straightening cycles. The copper was cooled to below room temperature before each RCS cycle. The grain size obtained after the RCS process was in the range of twenty to a few hundred nanometers, and microhardness was increased by 100%. Both equilibrium and non-equilibrium grain boundaries are observed. This work demonstrates the capability of the RCS process in refining grain size of metal materials. The RCS process can be easily adapted to large-scale industrial production and has the potential to pave the way to large-scale structural applications of nanostructured materials.

  2. Vision system for gauging and automatic straightening of steel bars

    NASA Astrophysics Data System (ADS)

    Sidla, Oliver; Wilding, Ernst; Niel, Albert; Barg, Herbert

    2001-02-01

    A machine vision application for the fully automatic straightening of steel bars is presented. The bars with lengths of up to 6000 mm are quite bent on exit of the rolling mill and need to be straightened prior to delivery to a customer. The shape of the steel bar is extracted and measured by two video resolution cameras which are calibrated in position and viewing angle relative to a coordinate system located in the center of the roller table. Its contour is tracked and located with a dynamic programming method utilizing several constraints to make the algorithm as robust as possible. 3D camera calibration allows the transformation of image coordinates to real-world coordinates. After smoothing and spline fitting the curvature of the bar is computed. A deformation model of the effect of force applied to the steel allows the system to generate press commands which state where and with what specific pressure the bar has to be processed. The model can be used to predict the straightening of the bar over some consecutive pressing events helping to optimize the operation. The process of measurement and pressing is repeated until the straightness of the bar reaches a predefined limit.

  3. Straightening tubular flow for side-by-side visualization.

    PubMed

    Angelelli, Paolo; Hauser, Helwig

    2011-12-01

    Flows through tubular structures are common in many fields, including blood flow in medicine and tubular fluid flows in engineering. The analysis of such flows is often done with a strong reference to the main flow direction along the tubular boundary. In this paper we present an approach for straightening the visualization of tubular flow. By aligning the main reference direction of the flow, i.e., the center line of the bounding tubular structure, with one axis of the screen, we are able to natively juxtapose (1.) different visualizations of the same flow, either utilizing different flow visualization techniques, or by varying parameters of a chosen approach such as the choice of seeding locations for integration-based flow visualization, (2.) the different time steps of a time-dependent flow, (3.) different projections around the center line , and (4.) quantitative flow visualizations in immediate spatial relation to the more qualitative classical flow visualization. We describe how to utilize this approach for an informative interactive visual analysis. We demonstrate the potential of our approach by visualizing two datasets from two different fields: an arterial blood flow measurement and a tubular gas flow simulation from the automotive industry. PMID:22034324

  4. A conjecture of Procesi and the straightening algorithm of Rota.

    PubMed Central

    Allen, E E

    1992-01-01

    Let R = Q[x1, x2,..., xn] and R* denote the quotient of R by the ideal generated by the elementary symmetric functions. R*, under the action of Sn, yields a graded version of the left regular representation. Procesi asked for a basis of R* consisting of homogeneous polynomials Gamma[S, C] indexed by pairs of tableaux, with S standard and C cocharge, that exhibits the decomposition of R* into its irreducible components. Procesi also suggested a way to construct the Gamma[S, C]. Using Rota's straightening algorithm, I show that certain polynomials [S, C] closely related to the Gamma[S, C] terms yield the desired basis. Parallel to the ring R* there is a family of Sn-modules R that have recently been studied by Garsia and Procesi. These modules have a graded character that is closely related to the q-Kostka-Foulkes polynomials Klambdamu(q). The [S, C] can be shown to yield also a basis when restricted to a given R. Through this connection the work reported here leads to an additional way of proving the charge interpretation for the polynomials Klambdamu(q). PMID:11607289

  5. Comparison of Nozzle and Flow Straighteners for Tank Waste Sluicing Applications Letter Report

    SciTech Connect

    Mullen, O Dennis; Jackson, David R.

    2000-09-29

    Nozzles and flow straighteners were compared to assess the relative quality of the water streams for sluicing waste from underground storage tankes. The criteria for comparison were 1) the impact force produced by the streams over a range of distance from the nozzle impinging on target plates, and 2) the coherence of the streams as manifest by the variation of force on targets of two different sizes. It was determined that 1) the standard Hanford flow straightener is measurable less effective than a commercial firefighting flow straightener at producing a coherent stream when used with the standard Hanford nozzle, and 2) a lighter and more compact firefighting deluge nozzle will deliver a stream of equal quality to that from the Hanford nozzle when either nozzle is used with the commercial flow straightener.

  6. Progressive hair straightening using an automated flat iron: function of silicones.

    PubMed

    Dussaud, Anne; Rana, Bhavna; Lam, Hui Tung

    2013-01-01

    An automated hair iron was built with which the hair temperature, contact force of the iron against the hair tress, and gliding speed were controlled. The changes in keratin were characterized by several techniques including differential scanning calorimetry, birefringence measurements, and wet tensile tests. Undamaged curly hair was ironed for several iron cycles at temperatures ranging from 120°C to 175°C and washed between each iron cycle. Irreversible straightening of curly hair was observed and depended on the temperature and the number of cycles. The birefringence data suggested that the straightening was related to a gradual decrease of the microfilament organization. Silicone treatment did not significantly affect the course of microfilament denaturation, but it improved the quality of straightening. It enhanced the fiber alignment under the gliding action of the iron. Progressive thermal straightening may be a promising method to achieve permanent smoothing of curly hair without chemical treatment. Ironing at the onset temperature (∼154°C), before substantial disulfide bond scission occurred, seemed to be a good compromise between process speed, straightening performance, and hair integrity (i.e., reduced loss of cross-linking). PMID:23578835

  7. Method for producing ultrafine-grained materials using repetitive corrugation and straightening

    DOEpatents

    Zhu, Yuntian T.; Lowe, Terry C.; Jiang, Honggang; Huang, Jianyu

    2001-01-01

    A method of refining the grain structure and improving the hardness and strength properties of a metal or metal alloy workpiece is disclosed. The workpiece is subjected to forces that corrugate and then straighten the workpiece. These steps are repeated until an ultrafine-grained product having improved hardness and strength is produced.

  8. HEU Holdup Measurements in the 321-M Draw Bench, Straightener, and Fluoroscope Components

    SciTech Connect

    Dewberry, R.A.

    2001-07-10

    The Analytical Development Section of Savannah River Technology Center (SRTC) was requested by the Facilities Disposition Division (FDD) to determine the holdup of enriched uranium in the 321-M facility as part of an overall deactivation project of the facility. This report covers holdup measurements of uranium residue on the draw bench, straightener, and the fluoroscope components of the 321-M facility.

  9. Hemodynamic Effects of Stent Struts versus Straightening of Vessels in Stent-Assisted Coil Embolization for Sidewall Cerebral Aneurysms

    PubMed Central

    Kono, Kenichi; Shintani, Aki; Terada, Tomoaki

    2014-01-01

    Background Recent clinical studies have shown that recanalization rates are lower in stent-assisted coil embolization than in coiling alone in the treatment of cerebral aneurysms. Objective This study aimed to assess and compare the hemodynamic effect of stent struts and straightening of vessels by stent placement on reducing flow velocity in sidewall aneurysms, with the goal of reducing recanalization rates. Methods We evaluated 16 sidewall aneurysms treated with Enterprise stents. We performed computational fluid dynamics simulations using patient-specific geometries before and after treatment, with or without stent struts. Results Stent placement straightened vessels by a mean (±standard deviation) of 12.9°±13.1° 6 months after treatment. Placement of stent struts in the initial vessel geometries reduced flow velocity in aneurysms by 23.1%±6.3%. Straightening of vessels without stent struts reduced flow velocity by 9.6%±12.6%. Stent struts had significantly stronger effects on reducing flow velocity than straightening (P = 0.004, Wilcoxon test). Deviation of the effects was larger by straightening than by stent struts (P = 0.01, F-test). The combination of stent struts and straightening reduced flow velocity by 32.6%±12.2%. There was a trend that larger inflow angles produced a larger reduction in flow velocity by straightening of vessels (P = 0.16). Conclusion In sidewall aneurysms, stent struts have stronger effects (approximately 2 times) on reduction in flow velocity than straightening of vessels. Hemodynamic effects by straightening vary in each case and can be predicted by inflow angles of pre-operative vessel geometry. These results may be useful to design a treatment strategy for reducing recanalization rates. PMID:25247794

  10. Influence of thermal hair straightening on ethyl glucuronide content in hair.

    PubMed

    Ettlinger, Jana; Kirchen, Luc; Yegles, Michel

    2014-06-01

    Hair analysis of ethyl glucuronide (EtG) has become a valuable marker for the detection of moderate and chronic alcohol consumption. It has been shown that bleaching and perming may decrease EtG content in hair. So far, no studies exist about the influence of thermal hair straightening on EtG content in hair. Forty-one positive EtG hair samples were treated in vitro with a hair straightener at 200°C. Duration of treatment of 1 min was chosen for this study. After washing, pulverization, incubation in ultrasonic bath, solid-phase extraction, and derivatization with heptafluorobutyric anhydride, EtG was determined by gas chromatography-mass spectrometry - negative ion chemical ionization (GC-MS-NICI). The EtG contents in straightened hair strands were then compared with those in the corresponding untreated strands. In 20 of 41 hair samples, a decrease of EtG content was found ranging from 0.7% to 79.3% (average 20%) whereas in 21 cases an increase was shown ranging from 2.0% to 50.9% (average 15%). The variation of the results seems to depend on hair colour. The decrease may be explained by thermic in vitro destruction of EtG. The increase may be explained by denaturation of the hair matrix by thermal treatment possibly causing a better extraction of EtG during incubation in ultrasonic bath. This in vitro study indicates that thermal hair straightening has an impact on the EtG content in hair. This has to be considered for a correct interpretation of EtG results in hair. However, these results should be confirmed by in vivo studies. PMID:24817051

  11. Influence of thermal hair straightening on cannabis and cocaine content in hair.

    PubMed

    Ettlinger, Jana; Yegles, Michel

    2016-08-01

    It has been shown that cosmetic treatment like bleaching and perming may lead to an important decrease of drugs of abuse content in hair. Currently, hair straightening has become a regular hair treatment especially for women. The aim of this preliminary study was to investigate the effect of in vitro treatment of hair with heat straightener on cannabis and cocaine concentrations in hair. 17 positive cannabis and 7 positive cocaine hair samples were treated in vitro with a hair straightener. During this treatment hair was put sequentially 30 times in contact with heated iron plates at 200°C during 2s corresponding to a total time of contact of 1min. THC and Cannabinol (CBN) were analysed in cannabis positive hair and cocaine, benzoylecgonin (BZE) and cocaethylene were analysed in cocaine positive hair. Analyses were performed with routine methods using GC/MS in electron impact mode. Regarding cannabis results a decrease of THC concentrations was found in 11 of 17 hair samples after thermal treatment, whereas in 6 cases an increase was shown. In all the hair samples CBN concentrations was explicitly higher after the in vitro treatment. Regarding cocaine results cocaine and cocaethylene concentrations decreased after treatment in all seven hair samples; in contrast, higher concentrations of BZE were determined. The strong increase of CBN and BZE content in hair after thermal treatments may be due to the fact that THC is converted by heat into CBN and cocaine into BZE, thus changing the respective ratios of the analysed substances. In conclusion, thermal straightening should be considered as other cosmetic hair treatments for a correct interpretation of hair results. PMID:26826847

  12. Formaldehyde in hair straightening products: rapid ¹H NMR determination and risk assessment.

    PubMed

    Monakhova, Yulia B; Kuballa, Thomas; Mildau, Gerd; Kratz, Evamaria; Keck-Wilhelm, Andrea; Tschiersch, Christopher; Lachenmeier, Dirk W

    2013-04-01

    Despite official regulations, the illegal use of formaldehyde-containing or releasing hair straightening products has become a popular practice in Europe and high contents of formaldehyde in such products have been reported. In this study, a methodology utilizing (1)H NMR spectroscopy has been developed to measure the concentration of formaldehyde in hair straightening products. For sample preparation, a dilution and alkaline hydrolysis is required. The total formaldehyde content can then be quantified by a distinct peak of the CH2 group of the methanediol molecule in the δ4.84-4.82 ppm range. The developed methodology was applied for the analysis of 10 hair straightening products. Seven of these products contained detectable amounts of formaldehyde that were higher than the maximum allowed concentration of 0.2%. The formaldehyde content of these products was found to be in the range 0.42-5.83% with an average concentration of 1.46%. The accuracy and reliability of the NMR results were confirmed by the EU reference photometric method. The air formaldehyde concentrations after application of hair straightening products were estimated in ranges 20-423 ppm and 1-18 ppm (for 1 and 24 m(3) salon volume). A probabilistic exposure estimation using Monte Carlo simulation found the average formaldehyde concentration to be 6 ppm (standard deviation 15 ppm). All exposure scenarios considerably exceeded the safe level of 0.1 ppm. Our findings confirmed that the risk of cosmetic formulations with formaldehyde above 0.2% is not negligible, as these products may facilitate considerable exposure of formaldehyde for consumers especially for salon workers. PMID:23216202

  13. Effect of Patency File on Transportation and Curve Straightening in Canal Preparation with ProTaper System

    PubMed Central

    Hasheminia, Seyed Mohsen

    2013-01-01

    The aim of this ex vivo study was to evaluate the effect of using a patency file on apical transportation and curve straightening during canal instrumentation with the ProTaper rotary system. Seventy permanent mandibular first molars with mesiobuccal canals, measuring 18–23 mm in length and with a 25–40° curvature (according to the Schneider method), were selected. The working lengths were determined and the teeth were mounted and divided into two experimental groups: (A) prepared by the ProTaper system without using a patency file (n = 35) and (B) prepared by the ProTaper system using a patency file (n = 35). Radiographs taken before and after the preparation were imported into Photoshop software and the apical transportation, and curve straightening were measured. Data were analyzed using independent t-test. Partial correlation analysis was performed to evaluate the relationship between the initial curvature, transportation, and curve straightening (α = 0.05). Using a patency file during canal preparation significantly decreased both apical transportation and curve straightening (P < 0.001). There were significant relationships between the angle of curvature, transportation and curve straightening in pairs (P < 0.001). Apical patency is recommended during root canal preparation with the ProTaper rotary system. PMID:24159390

  14. Influence of chemical straightening on the stability of drugs of abuse in hair.

    PubMed

    Pritchett, Jeanita S; Phinney, Karen W

    2015-01-01

    Chemical straightening, also known as a relaxer, is ubiquitously used among African American women to obtain straighter hair compared with their natural tresses. This study focused on the stability of drugs of abuse in hair after a single application of the relaxer. Commercially available 'Lye' or 'No-Lye' chemical straightening products (Silk Elements™) were applied in vitro to drug-fortified hair (standard reference materials (SRM) 2379 and 2380) and hairs clipped from established drug users. Target analytes (cocaine (COC), benzoylecgonine (BZE), cocaethylene (CE), phencyclidine and tetrahydrocannabinol) were isolated using solid-phase extraction and then analyzed with isotope dilution gas chromatography-mass spectrometry with selective ion monitoring. After either treatment, drug concentrations were significantly (P < 0.05) decreased in both the SRM sample and the hair from authentic abusers. In the SRM groups, 6-67% of the original concentration remained after a single chemical treatment. Similarly, only 5-30% of the original concentration remained in authentic drug hairs that had formerly tested positive for COC, BZE and CE. PMID:25298521

  15. Gravitropism of oat and wheat coleoptiles: dependence on the stimulation angle and involvement of autotropic straightening.

    PubMed

    Tarui, Y; Iino, M

    1997-12-01

    Gravitropism of oat (Avena sativa L.) and wheat (Triticum aestivum L.) coleoptiles was investigated in relation to the displacement angle or to the initially set stimulation angle (SA). We measured curvature rates at the early phase of curvature, before it was affected by the drop in SA resulting from the curvature response itself. The plot of the rates against the sines of initial SAs revealed similar curves for oats and wheat, which approached saturation as the sine increased to unity. The two species and previously analyzed rice [Iino et al. (1996) Plant Cell Environ. 19: 1160] appeared to have similar gravisensitivities. Initial SAs below and over 90 degrees yielded comparable rates when the sine values were the same, indicating that the extent of gravitropism is determined by the gravity component perpendicular to the organ's long axis. Long-term curvature kinetics at different SAs indicated that the net curvature rate dropped sharply before the tip reached the vertical position and then the tip approached the vertical slowly, with clear oscillatory movements in the case of wheat. During this late curvature phase, the coleoptile straightened gradually, although none of its parts had yet reached the vertical. When rotated on horizontal clinostats or displaced upwards to reduce SA in the late curvature phase, coleoptiles bent in the opposite direction. These results demonstrated that autotropism counteracts gravitropism to straighten coleoptiles. PMID:11536867

  16. Nanobubbles stability and multiwall carbon nanotubes straightening on few-layer graphene surfaces

    NASA Astrophysics Data System (ADS)

    Al-Harthi, S. H.; Al-Barwani, M.; Elzain, M.; Al-Naamani, N.; Hysen, T.

    2011-08-01

    The formation of nanobubbles, straightening, and orientation of multiwalled carbon nanotubes (MWCNTs) are investigated by preparing thin films employing dip casting of colloidal solutions on few-layer graphene (FLG) surfaces. In contrast to what is known, it is observed that nanobubbles are formed on an ultrathin dewetted layer of 0.5 nm thickness and exhibit unusual stability at ultrahigh vacuum conditions. Further, nanobubble rings are observed at atmospheric pressure. The results provide direct experimental evidence of the interaction between MWCNTs and nanobubbles at air-liquid-solid triple contact line and at lower step edge of the FLG, which together lead to the alignment of MWCNTs. Due to the balance between the surface tension forces and the strain forces arising from tube bending, MWCNTs attained straight rod-like shape. This enabled us to evaluate the elastic modulus of the MWCNT as E = 0.9 TPa.

  17. Three-Dimensional Analysis of Spiny Dendrites Using Straightening and Unrolling Transforms

    PubMed Central

    Morales, Juan; Benavides-Piccione, Ruth; Pastor, Luis; Yuste, Rafael; DeFelipe, Javier

    2014-01-01

    Current understanding of the synaptic organization of the brain depends to a large extent on knowledge about the synaptic inputs to the neurons. Indeed, the dendritic surfaces of pyramidal cells (the most common neuron in the cerebral cortex) are covered by thin protrusions named dendritic spines. These represent the targets of most excitatory synapses in the cerebral cortex and therefore, dendritic spines prove critical in learning, memory and cognition. This paper presents a new method that facilitates the analysis of the 3D structure of spine insertions in dendrites, providing insight on spine distribution patterns. This method is based both on the implementation of straightening and unrolling transformations to move the analysis process to a planar, unfolded arrangement, and on the design of DISPINE, an interactive environment that supports the visual analysis of 3D patterns. PMID:22644869

  18. Active self-correction of back posture in children instructed with 'straighten your back' command.

    PubMed

    Czaprowski, Dariusz; Pawłowska, Paulina; Stoliński, Lukasz; Kotwicki, Tomasz

    2014-10-01

    The ability to adopt the properly corrected body posture is one of the factors determining the effectiveness of therapeutic programmes. This study determined the active self-correction expressed by the change of sagittal spinal curvatures (in standing and sitting positions) in 249 children (136 females, 113 males, aged 10-14 years) instructed with 'straighten your back' command (SYB). Spinal curvatures (sacral slope-SS, lumbar lordosis-LL, global, lower and upper thoracic kyphosis-TK, LK, UK, respectively) were assessed using Saunders inclinometer. The assessment was done in spontaneous standing and sitting positions and in the positions adopted after the SYB. In a standing position SYB led to the significant (P < 0.001) increase in SS, and the significant (P < 0.01) decrease in LL, TK, LK, UK. In a sitting position SYB led to significant changes (P < 0.001) from kyphotic to lordotic position of SS and LL and to the significant (P < 0.001) reduction of TK (36.5° ± 10.8 vs. 23.5° ± 11) and the flattening of LK (15.2° ± 8.7 vs. 1.0° ± 8.4). There were gender-based discrepancy regarding active self-correction only for LL in a standing and UK in a sitting position. Females demonstrated a significant decrease in LL (P < 0.001). UK significantly increased only in males (P < 0.001). The 'straighten your back' command leads to moving the spine away from mid-range towards end range of motion. Therefore, the command should not be used to elicit the most optimal back posture. Further studies are needed to determine if the active self-correction is different in females and males. PMID:24246905

  19. Assessment of Management Strategies for a Straightened Lowland Agricultural Stream in Southwestern Québec

    NASA Astrophysics Data System (ADS)

    Rousseau, Y.; Biron, P.

    2009-05-01

    Channel straightening and dredging were extensively used in the 20th century to improve agricultural fields' drainage efficiency and facilitate crop maintenance and harvest. Although the adverse geomorphologic and ecological effects of this practice on hydrologic networks are widely acknowledged, alternative management strategies remain marginal in Southwestern Québec. Furthermore, bank stabilization projects are often carried out to mitigate erosion at a local scale with little concern about the watershed scale, i.e. treating the symptom rather than the cause of erosion, and with little guidance on suitable designs for specific areas. We present here the results of a case study conducted in a small straightened agricultural stream in the St. Lawrence Lowlands (Richer stream, 45 km east of Montreal, Qc) to assess the efficiency of diverse instream structures to enhance bank stability. The loss in sinuosity and resultant increase in stream power in this stream resulted in acute erosion problems. A conceptual model developed in Java was developed to examine erosion processes at the watershed scale. This model is also used to parameterize a three-dimensional computational fluid dynamics model (Phoenics) to investigate the effects on flow field of employing various types of instream structures in a section of the Richer Stream which is particularly problematic for river management because of residential development and very limited space available for riparian zones. Model validation was achieved using flow velocity measurements obtained with an Acoustic Doppler Velocimeter. Simulation outcomes are analysed with regards to strategies using geomorphological, economical and ecological criteria in an attempt to identify their efficiency. The methods presented here can help decreasing the high degree of uncertainty generally involved in restoration activities by better assessing the efficiency of specific stabilization techniques prior to their implementation while

  20. Transmembrane helix straightening and buckling underlies activation of mechanosensitive and thermosensitive K(2P) channels.

    PubMed

    Lolicato, Marco; Riegelhaupt, Paul M; Arrigoni, Cristina; Clark, Kimberly A; Minor, Daniel L

    2014-12-17

    Mechanical and thermal activation of ion channels is central to touch, thermosensation, and pain. The TRAAK/TREK K(2P) potassium channel subfamily produces background currents that alter neuronal excitability in response to pressure, temperature, signaling lipids, and anesthetics. How such diverse stimuli control channel function is unclear. Here we report structures of K(2P)4.1 (TRAAK) bearing C-type gate-activating mutations that reveal a tilting and straightening of the M4 inner transmembrane helix and a buckling of the M2 transmembrane helix. These conformational changes move M4 in a direction opposite to that in classical potassium channel activation mechanisms and open a passage lateral to the pore that faces the lipid bilayer inner leaflet. Together, our findings uncover a unique aspect of K(2P) modulation, indicate a means for how the K(2P) C-terminal cytoplasmic domain affects the C-type gate which lies ∼40Å away, and suggest how lipids and bilayer inner leaflet deformations may gate the channel. PMID:25500157

  1. Analytical treatment of electron trajectory straightener issues in free-electron lasers

    SciTech Connect

    Elliott, C.J.; Quimby, D.C.; Spectra Technology, Inc., Bellevue, WA )

    1989-01-01

    The poincare orbit of the electron's journey must be straight and narrow through a many period FEL. To utilize an available technology level, the straightest wiggler orbit operating point (SWOOP) is chosen by adjusting the spacing parameter of an orbit correction scheme. This eases the requirements for achieving the full potential of FEL wigglers. One quality index, one cost index, two quality factors, two measures of field noise, an improvement index, and a straightener classification scheme are concepts that facilitate the analysis. Only when the field noise is large, is this analysis of direct use. A reader-friendly description culminates in the comparison of two schemes to illustrate the methods. Two coupled first order langevin equations have solutions that are proven to be gaussian variables. The solutions are used to give the required cross correlations. These results are coupled with a simple graphical technique and give an expression for the angular variance in the correction corridor. The two components of this variance are compared to a fiducial scheme and yield the two quality factors from which the quality, improvement and cost indices are computed. 68 refs., 5 figs.

  2. Measuring OutdoorAir Intake Rates Using Electronic Velocity Sensors at Louvers and Downstream of Airflow Straighteners

    SciTech Connect

    Fisk, William; Sullivan, Douglas; Cohen, Sebastian; Han, Hwataik

    2008-10-01

    Practical and accurate technologies are needed for continuously measuring and controlling outdoor air (OA) intake rates in commercial building heating, ventilating, and air conditioning (HVAC) systems. This project evaluated two new measurement approaches. Laboratory experiments determined that OA flow rates were measurable with errors generally less than 10percent using electronic air velocity probes installed between OA intake louver blades or at the outlet face of louvers. High accuracy was maintained with OA flow rates as low as 15percent of the maximum for the louvers. Thus, with this measurement approach HVAC systems do not need separate OA intakes for minimum OA supply. System calibration parameters are required for each unique combination of louver type and velocity sensor location but calibrations are not necessary for each system installation. The research also determined that the accuracy of measuring OA flow rates with velocity probes located in the duct downstream of the intake louver was not improved by installing honeycomb airflow straighteners upstream of the probes. Errors varied with type of upstream louver, were as high as 100percent, and were often greater than 25percent. In conclusion, use of electronic air velocity probes between the blades of OA intake louvers or at the outlet face of louvers is a highly promising means of accurately measuring rates of OA flow into HVAC systems. The use of electronic velocity probes downstream of airflow straighteners is less promising, at least with the relatively small OA HVAC inlet systems employed in this research.

  3. Adolescent Idiopathic Scoliosis: A 71 Cases Study Ascertaining that Straightening Is Possible, and a New Etiological Hypothesis

    PubMed Central

    2013-01-01

    Study Design Seventy-one children (23 boys and 48 girls, aged 6 to 18 year-old) with adolescent idiopathic scoliosis (AIS) between 11° and 62°, without braces, have been treated manually, only at the level of the neck. Purpose To ascertain that non-surgical straightening of AIS is possible (without brace). Overview of Literature So far no disease modifying treatment for AIS existed. Braces can only slow down worsening (and this can only be achieved if they are worn 23 hours a day). Surgery is not without important risks. Methods All patients have been treated exclusively with a manual therapy called Brachy-Myotherapy. This method treats spasmed (contractured) muscles by placing them in a shortening position according to a specific protocol. Results An average straightening of 8° of AIS was observed, with a maximum of 25°. 94% of cases improved, 67 out of 71. The worst prognosis was, the better results. The more advanced AIS was, the better the results. Conclusions A simple and reliable treatment of AIS is possible. AIS seems to be a compensation mechanism of the body, with the aim of keeping the ears, and thus the labyrinths, at a horizontal level for correct equilibrium. When lasting post-traumatic neck muscle contractures causing a permanent side-bending of the skull have been treated, this compensation mechanism becomes irrelevant and scoliosis tends to subside. PMID:24353844

  4. Environmental and biological monitoring of occupational formaldehyde exposure resulting from the use of products for hair straightening.

    PubMed

    Peteffi, Giovana Piva; Antunes, Marina Venzon; Carrer, Caroline; Valandro, Eduarda Trevizani; Santos, Sílvia; Glaeser, Jéssica; Mattos, Larissa; da Silva, Luciano Basso; Linden, Rafael

    2016-01-01

    The evaluation of formaldehyde (FD) exposure in beauty salons, due to the use of hair straightening products, and its relation with genotoxicity biomarkers was performed in this study. Regardless of official recommendations, the inappropriate use of homemade hair creams has became a popular practice in Brazil, and high formaldehyde content in the "progressive straightening" creams can contain mutagens that could increase the incidence of neoplasia in those people who use them. Damage to DNA was assessed by conducting a micronuclei test (MNT) on buccal cells and the comet assay on heparinized venous blood samples. A total of 50 volunteers were recruited at six different beauty salons (labeled A to F). At two salons that used products that did not contain FD (salons D and E), environmental FD concentrations were 0.04 and 0.02 ppm. In contrast, the products used at salons A, B, C, and F contained 5.7, 2.61, 5.9, and 5.79% of FD, and these salons had environmental FD concentrations of 0.07, 0.14, 0.16, and 0.14 ppm, respectively. Comparison of the beauty salon workers from each of the six beauty salons revealed significant differences in urinary formic acid (FA) concentration before exposure (p = 0.016), urinary FA after exposure (p = 0.004), variation in FA concentration before and after exposure (p = 0.018), environmental FD concentration (p < 0.001), cytogenetic damage detected by the comet assay according to both damage index (p < 0.001) and frequency of damage (p < 0.001), and for karyorrhexis only according to the MNT (p = 0.001). PMID:26351198

  5. Novel analytical method to measure formaldehyde release from heated hair straightening cosmetic products: Impact on risk assessment.

    PubMed

    Galli, Corrado Lodovico; Bettin, Federico; Metra, Pierre; Fidente, Paola; De Dominicis, Emiliano; Marinovich, Marina

    2015-08-01

    Hair straightening cosmetic products may contain formaldehyde (FA). In Europe, FA is permitted for use in personal care products at concentrations ⩽ 0.2g/100g. According to the Cosmetic Ingredient Review (CIR) Expert Panel products are safe when formalin (a 37% saturated solution of FA in water) concentration does not exceed 0.2g/100g (0.074 g/100g calculated as FA). The official method of reference does not discriminate between "free" FA and FA released into the air after heating FA donors. The method presented here captures and collects the FA released into the air from heated cosmetic products by derivatization with 2,4-dinitrophenylhydrazine and final analysis by UPLC/DAD instrument. Reliable data in terms of linearity, recovery, repeatability and sensitivity are obtained. On a total of 72 market cosmetic products analyzed, 42% showed FA concentrations very close to or above the threshold value (0.074 g/100g calculated as FA) suggested by the Cosmetic Ingredient Review committee, whereas 11 products, negative using the official method of reference, were close to or above the threshold value (0.074 g/100g calculated as FA). This may pose a health problem for occasional users and professional hair stylists. PMID:26003512

  6. Numerical modeling of gravel bed river response to meander straightening: The coupling between the evolution of bed pavement and long profile

    NASA Astrophysics Data System (ADS)

    Talbot, Tracey; Lapointe, Michel

    2002-06-01

    Artificial meander straightening (rectification) was conducted in the early 1960s along the Sainte-Marguerite River, Canada, in order to facilitate highway construction along the valley. Previous studies [Talbot and Lapointe, 2002] confirm that vertical reprofiling, coupled with pavement coarsening in the degrading reach, were the main responses counteracting the disequilibrium in gravel transport rates triggered at rectification of this system. Numerical simulations, using SEDROUT2.0, a one-dimensional hydraulic and sediment transport model, and validated against the observed channel response, show the important role played by an advancing wave of pavement coarsening down the rectified reach in modulating the bed degradation response. Simulations extending into the future reveal an asymptotically slowing approach to equilibrium in the middle of the 21st century, with a response half-time of the order of 10 years. In near-threshold gravel bed systems like the Sainte-Marguerite River, pavement coarsening after rectification buffers the system against extreme degradation. Most significantly for watershed management, this also appears to severely limit the extent of propagation of degradation upstream of the rectification.

  7. Subsurface Characterization of Mystic Lake Paleoseismic site on the Claremont Fault Using CPT Data: Evidence for Straightening of the northern San Jacinto Fault, California

    NASA Astrophysics Data System (ADS)

    Marliyani, G. I.; Rockwell, T. K.; Onderdonk, N.; McGill, S. F.

    2010-12-01

    We collected Cone Penetrometer Test (CPT) data along two transects across a small releasing step over at the Mystic Lake paleoseismic site along the Claremont segment of San Jacinto Fault, California. The primary reasons for this study are to characterize the Holocene pattern of sedimentation and to locate the most promising areas for additional trenching. At the depth of the trench, CPT data agree well with trench observations to better than 10cm resolution. The main fault identified in our 2009 trench is clearly the principal dip slip fault at depth, and shows increasing vertical separation with increasing depth. Based on limited shallow age data from the trench, the sedimentation rate varies by a factor of two across the main fault, making this an ideal paleoseismic site. The late Holocene sedimentation rate is 3-4 mm/yr within the small sag depression, with units at 2 m depth west of the fault appearing at 4-6 m depth east of the fault in the sag. As we only trenched to about 2 m depth, the current paleoseismic record of pre-historical events is probably a minimum. The young active fault is about 0.5 km from the basin bounding mapped trace of the Claremont fault, which displays minimal Holocene activity in our preliminary trenches. Along with the presence of young faults within the Mystic Lake step over between the Casa Loma and Claremont strands (also referred to as the Hemet step-over), as determined from seismic reflection and seismicity data, these observations suggest that the northern San Jacinto fault is reorganizing and straightening, and will eventually bypass this large releasing step in San Jacinto Valley, thereby lengthening the straight continuous section of San Jacinto Fault. Rupture of the entire Clark-Casa Loma-Claremont fault zone could result in earthquakes as large as Mw7.6, rivaling the San Andreas fault for hazard to the densely populated Los Angeles and San Bernardino/Riverside areas.

  8. STRAIGHTENING THE DENSITY-DISPLACEMENT RELATION WITH A LOGARITHMIC TRANSFORM

    SciTech Connect

    Falck, Bridget L.; Neyrinck, Mark C.; Aragon-Calvo, Miguel A.; Lavaux, Guilhem; Szalay, Alexander S.

    2012-01-20

    We investigate the use of a logarithmic density variable in estimating the Lagrangian displacement field motivated by the success of a logarithmic transformation in restoring information to the matter power spectrum. The logarithmic relation is an extension of the linear relation, motivated by the continuity equation, in which the density field is assumed to be proportional to the divergence of the displacement field; we compare the linear and logarithmic relations by measuring both of these fields directly in a cosmological N-body simulation. The relative success of the logarithmic and linear relations depends on the scale at which the density field is smoothed. Thus we explore several ways of measuring the density field, including Cloud-In-Cell smoothing, adaptive smoothing, and the (scale-independent) Delaunay tessellation, and we use both a Fourier-space and a geometrical tessellation approach to measuring the divergence. We find that the relation between the divergence of the displacement field and the density is significantly tighter and straighter with a logarithmic density variable, especially at low redshifts and for very small ({approx}2 h{sup -1} Mpc) smoothing scales. We find that the grid-based methods are more reliable than the tessellation-based method of calculating both the density and the divergence fields, though in both cases the logarithmic relation works better in the appropriate regime, which corresponds to nonlinear scales for the grid-based methods and low densities for the tessellation-based method.

  9. Characterization of formaldehyde exposure resulting from the use of four professional hair straightening products.

    PubMed

    Pierce, J S; Abelmann, A; Spicer, L J; Adams, R E; Glynn, M E; Neier, K; Finley, B L; Gaffney, S H

    2011-11-01

    An exposure simulation study was conducted to characterize potential formaldehyde exposures of salon workers and clients during keratin hair smoothing treatments. Four different hair treatment brands (Brazilian Blowout, Coppola, Global Keratin, and La Brasiliana) were applied to separate human hair wigs mounted on mannequin heads. Short-term (6-16 min) and long-term (41-371 min) personal and area samples (at distances of 0.5 to 3.0 m from the source) were collected during each treatment for the 1-day simulation. A total of 88 personal, area, and clearance samples were collected. Results were analyzed based on task sampling (blow-dry, flat-iron), treatment sampling (per hair product), and time-weighted averages (per hair treatment, four consecutive treatments). Real-time monitoring of tracer gas levels, for determining the air exchange rate, and formaldehyde levels were logged throughout the simulation. Bulk samples of each hair treatment were collected to identify and quantify formaldehyde and other chemical components that may degrade to formaldehyde under excessive heat. Mean airborne concentrations of formaldehyde ranged from 0.08-3.47 ppm during blow-dry and 0.08-1.05 ppm during flat-iron. During each treatment, the mean airborne concentrations ranged from 0.02-1.19 ppm throughout different zones of the salon. Estimated 8-hr time-weighted averages for one treatment per day ranged from 0.02 ppm for La Brasiliana to 0.08-0.16 ppm for Brazilian Blowout. For four treatments per day, means ranged from 0.04-0.05 ppm for La Brasiliana to 0.44-0.75 ppm for Brazilian Blowout. Using all four products in one day resulted in estimated 8-hr time-weighted averages ranging from 0.17-0.29 ppm. Results from bulk sampling reported formaldehyde concentrations of 11.5% in Brazilian Blowout, 8.3% in Global Keratin, 3% in Coppola, and 0% in La Brasiliana. Other products that degrade into formaldehyde were detected in Global Keratin, Coppola, and La Brasiliana. The results of this study show that professional hair smoothing treatments--even those labeled "formaldehyde-free"--have the potential to produce formaldehyde concentrations that meet or exceed current occupational exposure limits. PMID:22035353

  10. Let's Get This Straightened Out: Finding a Place and Presence for Sexual/Gender Identity-Difference in Peace Education

    ERIC Educational Resources Information Center

    Mizzi, Robert

    2010-01-01

    Expressions of homo/transphobia continue to rupture and sometimes even erase the lives of persons with sexual/gender identity-difference across the globe. Despite this, experiences with violence of this nature largely go unexamined in peace education scholarship. In order to begin a discussion about sexuality/gender identity-difference within a…

  11. Straighten the Back to Sit: Belly-Cultivation Techniques as "Modern Health Methods" in Japan, 1900-1945.

    PubMed

    Wu, Yu-Chuan

    2016-09-01

    In Japan, the first half of the twentieth century saw a remarkable revival of concern with the cultivation of the belly, with a variety of belly-cultivation techniques, particularly breathing exercise and meditative sitting, widely practiced for improving health and treating diseases. This article carefully examines some practitioners' experiences of belly-cultivation practice in attempting to understand its healing effects for them within their life histories and contemporary intellectual, social and cultural contexts. It shows that belly-cultivation practice served as a medium for some practitioners to reflect on and retell their life stories, and that the personal charisma of certain masters and the communities developing around them provided practitioners with a valuable sense of belonging in an increasingly industrialized and urbanized society. Moreover, these belly-cultivation techniques provided an embodied way for some to explore and affirm their sense of self and develop individual identity. While they were increasingly promoted as cultural traditions capable of cultivating national character, they also served as healing practices by inspiring practitioners with a sense of collective identity and purpose. With these analyses, this article sheds light on the complicated meanings of belly-cultivation for practitioners, and provides illustrative examples of the multitude of meanings of the body, bodily cultivation and healing. PMID:26848985

  12. Cold Saw Operator (iron & steel) 6-88.651; Cold Sizing Mill Operator (iron & steel) 4-88.315; Decambering Mill Operator (iron & steel) 6-88.346; Flying Cut-Off Machine Operator (iron & steel) 6-88.655; Rotary Straightener Operator (iron & steel) 6-88.346; Straightener Machine Operator (iron & steel) 6-88.354; Tube Straightener Operator (iron & steel) 6-88.346; Welder (iron & steel) 4-88.343; Welder, Assistant (iron & steel) 4-88.344--Technical

    ERIC Educational Resources Information Center

    Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.

    The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…

  13. Straightening of the northern San Jacinto Fault, California as seen in the fault structure evolution of the San Jacinto step-over

    NASA Astrophysics Data System (ADS)

    Marliyani, G. I.; Rockwell, T. K.; Onderdonk, N.; McGill, S. F.

    2011-12-01

    We investigate a releasing step-over between the Casa Loma and Claremont strands of the northern San Jacinto fault zone to evaluate the Late Quaternary structural evolution of the fault zone, and to assess the likelihood of a rupture jumping across the step-over. Our new CPT and trench observations along the Claremont fault at Mystic Lake indicate that the main strand of the Claremont fault has jumped nearly a half kilometer westward into the San Jacinto releasing step-over during the late Quaternary. Multiple faults are inferred from the CPT data within a small sag at the NE side of the step-over that cuts through younger stratigraphy to the west of the basin bounding fault near Mystic Lake. Previous seismic reflection data also suggest the presence of a young fault that cuts basin strata beneath the middle of Mystic Lake farther west from our study area, and seismicity observations are consistent with the hypothesis that new fault strands have formed within the step-over zone. Numerous tectono-geomorphic features observed in satellite and LiDAR DEM imagery are interpreted to delineate the location of the currently active faults, as well as a zone of faults that cut across the basin from the northern end of the Casa Loma fault to the southern end of the active trace of the Claremont fault. Finally, new paleoseismic data from Mystic Lake site suggest that some late Holocene earthquakes may have jumped the step-over. All of these observations suggest that the San Jacinto step-over, which has been used as the primary basis for segmenting the northern San Jacinto fault zone, is being by-passed and that the fault zone may now be capable of larger earthquakes than previously expected.

  14. Collagenase Clostridium Histolyticum Injection

    MedlinePlus

    ... make it difficult to straighten one or more fingers) when a cord of tissue can be felt ... the cord of thickened tissue and allows the finger(s) to be straightened. In people with Peyronie's disease, ...

  15. Mallet finger - aftercare

    MedlinePlus

    Baseball finger - aftercare; Drop finger - aftercare; Avulsion fracture - mallet finger - aftercare ... Mallet finger occurs when you cannot straighten your finger: when you try to straighten it, the tip of your ...

  16. Orthodontics and Aligners

    MedlinePlus

    ... Repairing Chipped Teeth Teeth Whitening Tooth-Colored Fillings Orthodontics and Aligners Straighten teeth for a healthier smile. Orthodontics When consumers think about orthodontics, braces are the ...

  17. The crooked nose.

    PubMed

    Shipchandler, Taha Z; Papel, Ira D

    2011-04-01

    Straightening a crooked nose is a challenge. Several techniques exist ranging from simple to technically complex. It is important to approach the nose systematically and to remember that perfection may be impossible to achieve. If straightening is not attainable, softening grafts or onlay grafts should be used to camouflage subtle irregularities. PMID:21404162

  18. Osteotomies in the crooked nose.

    PubMed

    Bloom, Jason D; Immerman, Sara B; Constantinides, Minas

    2011-10-01

    The crooked nasal pyramid and upper third of the nose can be straightened with various osteotomes. Appropriate solutions to maximize successful nasal straightening require a thorough knowledge of the anatomy, a comprehensive preoperative plan, and the appropriate osteotomy choice. PMID:22028010

  19. Rotary blood pump

    NASA Technical Reports Server (NTRS)

    Benkowski, Robert J. (Inventor); Kiris, Cetin (Inventor); Kwak, Dochan (Inventor); Rosenbaum, Bernard J. (Inventor); Bacak, James W. (Inventor); DeBakey, Michael E. (Inventor)

    1999-01-01

    A blood pump that comprises a pump housing having a blood flow path therethrough, a blood inlet, and a blood outlet; a stator mounted to the pump housing, the stator having a stator field winding for producing a stator magnetic field; a flow straightener located within the pump housing, and comprising a flow straightener hub and at least one flow straightener blade attached to the flow straightener hub; a rotor mounted within the pump housing for rotation in response to the stator magnetic field, the rotor comprising an inducer and an impeller; the inducer being located downstream of the flow straightener, and comprising an inducer hub and at least one inducer blade attached to the inducer hub; the impeller being located downstream of the inducer, and comprising an impeller hub and at least one impeller blade attached to the impeller hub; and preferably also comprising a diffuser downstream of the impeller, the diffuser comprising a diffuser hub and at least one diffuser blade. Blood flow stagnation and clot formation within the pump are minimized by, among other things, providing the inducer hub with a diameter greater than the diameter of the flow straightener hub; by optimizing the axial spacing between the flow straightener hub and the inducer hub, and between the impeller hub and the diffuser hub; by optimizing the inlet angle of the diffuser blades; and by providing fillets or curved transitions between the upstream end of the inducer hub and the shaft mounted therein, and between the impeller hub and the shaft mounted therein.

  20. Effect of channel plane form on formation process of Sandbars

    NASA Astrophysics Data System (ADS)

    Takahashi, Gen; Yasuda, Hiroyasu

    Almost no explanation is given about development process of sand bar in non-straighten channel because the phenomenon of sand bar has been investigated using straighten channel. This study conducted a numerical experiment of development process of sand bar in a meandering channel and a figure-of-eight(gourd) as fixed wall. The results shows that the development process clearly differs in channel of straighten, meandering and figure-of-eight(gourd). The result of figure-of-eight(gourd) doesn't occur mode degradation and keep multiple bars.

  1. Treatment of the scoliotic nose with extracorporeal septoplasty.

    PubMed

    Gubisch, Wolfgang

    2015-02-01

    A septal deformity with severe deviation of the septal L strut is seen in nearly every crooked or scoliotic nose. Unless the underlying septal deformity is properly diagnosed and treated, the nasal axis cannot be completely straightened. In addition, because standard septoplasty techniques often fail to adequately address severe L-strut deformities, extracorporeal septoplasty is often a prerequisite for straightening the crooked nose. This article presents a detailed explanation of the extracorporeal technique, as well as representative long-term clinical results showing the efficacy and durability of extracorporeal septoplasty. Extracorporeal septoplasty a safe and reliable method for straightening the severely deviated nose. PMID:25430926

  2. Irritant contact dermatitis complicated by deep-seated staphylococcal infection caused by a hair relaxer.

    PubMed

    Kaur, Birinder J; Singh, Harmeet; Lin-Greenberg, Alan

    2002-02-01

    Chemical hair relaxers are used by many women to straighten their hair. We describe a case of a deep soft tissue staphylococcal abscess that complicated an irritant contact dermatitis from a hair relaxer treatment. PMID:11853045

  3. Irritant contact dermatitis complicated by deep-seated staphylococcal infection caused by a hair relaxer.

    PubMed Central

    Kaur, Birinder J.; Singh, Harmeet; Lin-Greenberg, Alan

    2002-01-01

    Chemical hair relaxers are used by many women to straighten their hair. We describe a case of a deep soft tissue staphylococcal abscess that complicated an irritant contact dermatitis from a hair relaxer treatment. PMID:11853045

  4. Braces

    MedlinePlus

    ... that straightens your teeth faster and easier. The rubber bands that go along with braces come in ... kids just need regular braces with wires and rubber bands doing their jobs to keep pressure on ...

  5. Cosmetic Dentistry

    MedlinePlus

    If you have stained, broken or uneven teeth, cosmetic dentistry can help. Cosmetic dentistry is different from orthodontic treatment, which can straighten your teeth with braces or other devices. Cosmetic dental ...

  6. 15. VIEW LOOKING SOUTHWEST INSIDE OF THE 22' BAR MILL ...

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

    15. VIEW LOOKING SOUTHWEST INSIDE OF THE 22' BAR MILL SHIPPING BUILDING No. 1 AT THE 10' SUTTON BAR STRAIGHTENER. - U.S. Steel Duquesne Works, 22-Inch Bar Mill, Along Monongahela River, Duquesne, Allegheny County, PA

  7. Hair Treatments and Pregnancy

    MedlinePlus

    ... is likely that only a small amount of hair straightening products are actually absorbed into your system, so the developing baby would only be exposed to small amounts. I work full time as a cosmetologist and recently became ...

  8. What Is Scoliosis?

    MedlinePlus

    ... causes of idiopathic scoliosis. They have studied genetics, growth, and changes in the spine, muscles, and nerves. They are studying how different treatments can help to straighten the spine or keep curves from getting worse. They are also studying the ...

  9. Stream Channelization: Conflict Between Ditchers, Conservationists

    ERIC Educational Resources Information Center

    Gillette, Robert

    1972-01-01

    Summarizes the argument between the advocates of stream straightening for flood control, drainage, and navigation, and those concerned with the maintenance of ecological communities and the aesthetic values of natural" streams. (AL)

  10. Precise Restraightening of Bent Studs

    NASA Technical Reports Server (NTRS)

    Boardman, R. E.

    1982-01-01

    Special tool quickly bends studs back into shape accurately and safely by force applied by hydraulic ram, with deflection being measured by dial indicator. Ram and indicator can be interchanged for straightening in reverse direction.

  11. Femoral nerve damage (image)

    MedlinePlus

    The femoral nerve is located in the leg and supplies the muscles that assist help straighten the leg. It supplies sensation ... leg. One risk of damage to the femoral nerve is pelvic fracture. Symptoms of femoral nerve damage ...

  12. 21 CFR 888.3050 - Spinal interlaminal fixation orthosis.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... compression or distraction rod. The device is implanted, usually across three adjacent vertebrae, to straighten and immobilize the spine to allow bone grafts to unite and fuse the vertebrae together. The...

  13. 21 CFR 888.3050 - Spinal interlaminal fixation orthosis.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... compression or distraction rod. The device is implanted, usually across three adjacent vertebrae, to straighten and immobilize the spine to allow bone grafts to unite and fuse the vertebrae together. The...

  14. 21 CFR 888.3050 - Spinal interlaminal fixation orthosis.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... compression or distraction rod. The device is implanted, usually across three adjacent vertebrae, to straighten and immobilize the spine to allow bone grafts to unite and fuse the vertebrae together. The...

  15. 21 CFR 888.3050 - Spinal interlaminal fixation orthosis.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... compression or distraction rod. The device is implanted, usually across three adjacent vertebrae, to straighten and immobilize the spine to allow bone grafts to unite and fuse the vertebrae together. The...

  16. 21 CFR 888.3050 - Spinal interlaminal fixation orthosis.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... compression or distraction rod. The device is implanted, usually across three adjacent vertebrae, to straighten and immobilize the spine to allow bone grafts to unite and fuse the vertebrae together. The...

  17. Macroinvertebrate response to stream restoration by large wood addition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Channel incision processes resulting primarily from channel straightening/dredging and watershed deforestation have been among the most profound degradations in our streams. Physical changes to streams affected by channel incision processes have included significant increases in streambed degradatio...

  18. Metatarsus adductus

    MedlinePlus

    ... may be needed if the foot is very flexible and easy to straighten or move in the ... not improve or your child's foot is not flexible enough, other treatments will be tried: Stretching exercises ...

  19. Collagenase Clostridium Histolyticum Injection

    MedlinePlus

    ... disease (a thickening of tissue [plaque] inside the penis that causes the penis to curve). Collagenase Clostridium histolyticum injection is in ... the plaque of thickened tissue and allows the penis to be straightened.

  20. Cosmetic Dentistry

    MedlinePlus

    If you have stained, broken or uneven teeth, cosmetic dentistry can help. Cosmetic dentistry is different from orthodontic treatment, which can straighten your teeth with braces or other devices. Cosmetic dental procedures include Bleaching to make teeth whiter ...

  1. Waardenburg syndrome

    MedlinePlus

    ... heterochromia ) Pale color skin, hair, and eyes (partial albinism) Difficulty completely straightening joints Possible slight decrease in ... ncbi.nlm.nih.gov/pubmed/20301703 . Read More Albinism Autosomal dominant Hearing loss Update Date 8/1/ ...

  2. Autotropism, automorphogenesis, and gravity

    NASA Technical Reports Server (NTRS)

    Stankovic, B.; Volkmann, D.; Sack, F. D.

    1998-01-01

    Segments of organs that have undergone gravitropic curvature later straighten during the course of gravitropism or after the g-vector becomes randomized on a clinostat. Little is known about the mechanism underlying these and perhaps related phenomena which have been described with various overlapping terms such as autotropism, autotropic straightening, automorphosis, automorphogenesis, automorphic curvature, and gravitropic straightening. The types of phenomena that historically have been named by the above terms are reviewed critically with respect to an interaction with gravitropism. We suggest that the term "autotropism" should not be applied to the phenomenon of organ straightening that occurs during the course of gravitropism, since this straightening is part of a complex series of local growth adjustments overall through time, and since this phenomenon is not itself a tropistic response to a directional exogenous stimulus. It is suggested that the term autotropism should be used only for the phenomenon of organ straightening that occurs after the g-vector is randomized on a clinostat or withdrawn in the microgravity conditions of spaceflight. Usage of the term automorphogenesis is most appropriate for describing curvatures or orientations that result from morphological relationships such as in nastic curvatures.

  3. Developing processing techniques for Skylab data

    NASA Technical Reports Server (NTRS)

    Nalepka, R. F. (Principal Investigator); Malila, W. A.; Morgenstern, J. P.

    1975-01-01

    The author has identified the following significant results. The effects of misregistration and the scan-line-straightening algorithm on multispectral data were found to be: (1) there is greatly increased misregistration in scan-line-straightening data over conic data; (2) scanner caused misregistration between any pairs of channels may not be corrected for in scan-line-straightened data; and (3) this data will have few pure field center pixels than will conic data. A program SIMSIG was developed implementing the signature simulation model. Data processing stages of the experiment were carried out, and an analysis was made of the effects of spatial misregistration on field center classification accuracy. Fifteen signatures originally used for classifying the data were analyzed, showing the following breakdown: corn (4 signatures), trees (2), brush (1), grasses, weeds, etc. (5), bare soil (1), soybeans (1), and alfalfa (1).

  4. Kinetics for phototropic curvature by etiolated seedlings of Arabidopsis thaliana

    NASA Technical Reports Server (NTRS)

    Orbovic, V.; Poff, K. L.

    1991-01-01

    An infrared-imaging system has been used to study the influence of gravity on the kinetics of first positive phototropism. The development of phototropic curvature of etiolated seedlings of Arabidopsis thaliana was measured in the absence of visible radiation. Following a pulse of blue light, stationary seedlings curved to a maximum of approximately 16 degrees about 80 minutes after stimulation. The seedlings then curved upward again or straightened by about 6 degrees during the subsequent 100 minutes. Seedlings rotated on a clinostat reached a similar maximum curvature following photostimulation. These seedlings maintained that curvature for 30 to 40 minutes before subsequently straightening to the same extent as the stationary seedlings. It is concluded that straightening is not a consequence of gravitropism, although gravity has some effect on the phototropism kinetics.

  5. Kinetics for Phototropic Curvature by Etiolated Seedlings of Arabidopsis thaliana 1

    PubMed Central

    Orbović, Vladimir; Poff, Kenneth L.

    1991-01-01

    An infrared-imaging system has been used to study the influence of gravity on the kinetics of first positive phototropism. The development of phototropic curvature of etiolated seedlings of Arabidopsis thaliana was measured in the absence of visible radiation. Following a pulse of blue light, stationary seedlings curved to a maximum of approximately 16° about 80 minutes after stimulation. The seedlings then curved upward again or straightened by about 6° during the subsequent 100 minutes. Seedlings rotated on a clinostat reached a similar maximum curvature following photostimulation. These seedlings maintained that curvature for 30 to 40 minutes before subsequently straightening to the same extent as the stationary seedlings. It is concluded that straightening is not a consequence of gravitropism, although gravity has some effect on the phototropism kinetics. PMID:11538373

  6. Laser Welding of Large Scale Stainless Steel Aircraft Structures

    NASA Astrophysics Data System (ADS)

    Reitemeyer, D.; Schultz, V.; Syassen, F.; Seefeld, T.; Vollertsen, F.

    In this paper a welding process for large scale stainless steel structures is presented. The process was developed according to the requirements of an aircraft application. Therefore, stringers are welded on a skin sheet in a t-joint configuration. The 0.6 mm thickness parts are welded with a thin disc laser, seam length up to 1920 mm are demonstrated. The welding process causes angular distortions of the skin sheet which are compensated by a subsequent laser straightening process. Based on a model straightening process parameters matching the induced welding distortion are predicted. The process combination is successfully applied to stringer stiffened specimens.

  7. A Novel Representation for Riemannian Analysis of Elastic Curves in ℝn

    PubMed Central

    Joshi, Shantanu H.; Klassen, Eric; Srivastava, Anuj; Jermyn, Ian

    2011-01-01

    We propose a novel representation of continuous, closed curves in ℝn that is quite efficient for analyzing their shapes. We combine the strengths of two important ideas - elastic shape metric and path-straightening methods -in shape analysis and present a fast algorithm for finding geodesics in shape spaces. The elastic metric allows for optimal matching of features while path-straightening provides geodesics between curves. Efficiency results from the fact that the elastic metric becomes the simple 2 metric in the proposed representation. We present step-by-step algorithms for computing geodesics in this framework, and demonstrate them with 2-D as well as 3-D examples. PMID:21311729

  8. Evaluation of Root Canal Preparation Using Rotary System and Hand Instruments Assessed by Micro-Computed Tomography

    PubMed Central

    Stavileci, Miranda; Hoxha, Veton; Görduysus, Ömer; Tatar, Ilkan; Laperre, Kjell; Hostens, Jeroen; Küçükkaya, Selen; Muhaxheri, Edmond

    2015-01-01

    Background Complete mechanical preparation of the root canal system is rarely achieved. Therefore, the purpose of this study was to evaluate and compare the root canal shaping efficacy of ProTaper rotary files and standard stainless steel K-files using micro-computed tomography. Material/Methods Sixty extracted upper second premolars were selected and divided into 2 groups of 30 teeth each. Before preparation, all samples were scanned by micro-computed tomography. Thirty teeth were prepared with the ProTaper system and the other 30 with stainless steel files. After preparation, the untouched surface and root canal straightening were evaluated with micro-computed tomography. The percentage of untouched root canal surface was calculated in the coronal, middle, and apical parts of the canal. We also calculated straightening of the canal after root canal preparation. Results from the 2 groups were statistically compared using the Minitab statistical package. Results ProTaper rotary files left less untouched root canal surface compared with manual preparation in coronal, middle, and apical sector (p<0.001). Similarly, there was a statistically significant difference in root canal straightening after preparation between the techniques (p<0.001). Conclusions Neither manual nor rotary techniques completely prepared the root canal, and both techniques caused slight straightening of the root canal. PMID:26092929

  9. V-TECS Guide for Auto Body Repair.

    ERIC Educational Resources Information Center

    Gregory, Margaret R.; Benson, Robert T.

    This curriculum guide consists of materials for teaching a course in auto body repair. Addressed in the individual units of the guide are the following topics: the nature and scope of auto body repair; safety; tools; auto body construction; simple metal straightening; welding; painting and refinishing; refinishing complete lacquer; refinishing…

  10. Influence of Physical Habitat and Agricultural Contaminants on Fishes within Agricultural Drainage Ditches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural drainage ditches are used within agricultural watersheds for the removal of excess water from agricultural fields. These headwater streams have been constructed or modified so they possess an enlarged trapezoidal cross-section, straightened channels, and riparian zones lacking woody veg...

  11. Surgery for Peyronie's disease

    PubMed Central

    Levine, Laurence A; Larsen, Stephen M

    2013-01-01

    Peyronie's disease (PD) is most simply referred to as a fibrotic wound-healing disorder of the tunica albuginea. It is both a physically and psychologically devastating disorder that causes penile deformity, curvature, hinging, narrowing and shortening, which may compromise sexual function. Although a variety of non-surgical treatments have been suggested, none to date offer a reliable and effective correction of the penile deformity. As a result, surgery remains the gold standard treatment option, offering the most rapid and reliable treatment which will be the focus of this article. We review the preoperative evaluation, surgical algorithm, graft materials and postoperative management of PD. Outcomes for tunical shortening, tunical lengthening and penile prosthesis placement for penile straightening are reviewed. Tunica albuginea plication is the preferred method of straightening for men with adequate rigidity and less severe disease defined as curvature less than 70° without narrowing/hinging. Men who have more severe, complex deformity, but maintain strong preoperative erectile function should be considered candidates for straightening with plaque incision or partial excision and grafting. Finally, for those men who have inadequate rigidity and PD, penile prosthesis placement with straightening is the best approach to address both problems. PMID:23178395

  12. Trigger Finger

    MedlinePlus

    ... it difficult to straighten the finger. Reproduced and adapted from Griffin LY (ed): Essentials of Musculoskeletal Care. ... surgery, the tendon sheath is cut. Reproduced and adapted from Griffin LY (ed): Essentials of Musculo- skeletal ...

  13. Speakeasy: A Text for Speaking, Volume 2. English for Special Purposes Series: Autobody Repair.

    ERIC Educational Resources Information Center

    Peet, William, Jr.

    This is the second of two volumes devoted to dialogs designed for classroom use by students of English as a second language. Survival skills are emphasized. The dialogs are grouped under the following titles: (1) "Buying Furniture," (2) "Straightening Metal Surfaces," (3) "Opening a Checking Account," (4) "Going to the Doctor," (5) "Building…

  14. Andy Wants to Be Grown Up: Managing Parental Anxiety.

    ERIC Educational Resources Information Center

    Hamilton, Jennifer

    1980-01-01

    The mother of a moderately retarded 11-year-old boy describes her reactions to having her son's teeth straightened. The author realized that the anxiety she felt about the orthodontic procedure was not so much concern for her son as her own fear of dental work. (PHR)

  15. 7 CFR 201.56-7 - Lily family, Liliaceae.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... growing point, provided other essential structures are normal. (v) Root system: A long slender primary... emerges with the seed coat and endosperm attached to the tip. A sharp bend known as the “knee” forms... cotyledon tip is pulled from the soil and straightens except for a slight kink which remains at the site...

  16. 7 CFR 201.56-7 - Lily family, Liliaceae.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... growing point, provided other essential structures are normal. (v) Root system: A long slender primary... emerges with the seed coat and endosperm attached to the tip. A sharp bend known as the “knee” forms... cotyledon tip is pulled from the soil and straightens except for a slight kink which remains at the site...

  17. Bilingual Skills Training Program. Auto Body Repair. Module 3.0: Basic Metal Repair.

    ERIC Educational Resources Information Center

    Northern New Mexico Community Coll., El Rito.

    This module on basic metal repair is the third of four (CE 028 303-306) in the auto body repair course of a bilingual vocational training program. The course is designed to furnish theoretical and laboratory experience in welding, metal straightening, metal finishing, painting, and use of power and hand tools. Module objectives are for students to…

  18. Bilingual Vocational Training Program. Auto Body Repair. Module 4.0: Auto Body Welding.

    ERIC Educational Resources Information Center

    Northern New Mexico Community Coll., El Rito.

    This module on auto body welding is the fourth of four (CE 028 303-306) in the auto body repair course of a bilingual vocational training program. The course is designed to furnish theoretical and laboratory experience in welding, metal straightening, metal finishing, painting, and use of power and hand tools. Module objectives are for students to…

  19. Barber/Cosmetologist Curriculum. Program Information.

    ERIC Educational Resources Information Center

    Moraine Park Technical Coll., Fond du Lac, WI.

    This guide provides the instructor with materials for a barber/cosmetologist program. Seventeen study guides are provided: anatomy and physiology; applied chemistry; chemical straightening/relaxing; chemical waving; electricity and light therapy; facial services; hair coloring and lightening (bleach); hair cutting; hair, skin, and nail disorders;…

  20. Bilingual Vocational Training Program. Auto Body Repair. Module 1.0: Beginning Auto Body.

    ERIC Educational Resources Information Center

    Northern New Mexico Community Coll., El Rito.

    This module on beginning auto body is the first of four (CE 028 303-306) in the auto body repair course of a bilingual vocational training program. The course is designed to furnish theoretical and laboratory experience in welding, metal straightening, metal finishing, painting, and use of power and hand tools. Module objectives are for students…

  1. 40 CFR 63.1452 - What are my monitoring requirements?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... device, associated sensor(s), and recording equipment according to the manufacturers' specifications. Locate the sensor(s) used for monitoring in or as close to a position that provides a representative... section. (i) Locate the flow sensor and other necessary equipment such as straightening vanes in...

  2. Tennis Rackets and the Parallel Axis Theorem

    NASA Astrophysics Data System (ADS)

    Christie, Derek

    2014-04-01

    This simple experiment uses an unusual graph straightening exercise to confirm the parallel axis theorem for an irregular object. Along the way, it estimates experimental values for g and the moment of inertia of a tennis racket. We use Excel to find a 95% confidence interval for the true values.

  3. Oversight of the Indian Child Welfare Act. Hearing before the Select Committee on Indian Affairs, United States Senate, Ninety-Sixth Congress, Second Session on Oversight of the Indian Child Welfare Act (Public Law 95-608).

    ERIC Educational Resources Information Center

    Congress of the U.S., Washington, DC. Senate Select Committee on Indian Affairs.

    The Select Committee on Indian Affairs met on June 30, 1980, for an oversight hearing on the Indian Child Welfare Act of 1978 to correct flaws and straighten out problems concerning Public Law 95-608 and the way it is implemented. Various members of the administration and a group of Indian leaders from across the country attended the hearing, at…

  4. Flaunting It for Social Justice

    ERIC Educational Resources Information Center

    Jackson, Janna

    2010-01-01

    By examining various movements in education in "Flaunt It! Queers Organizing for Public Education and Justice," Quinn and Meiners show a systematic and intentional "straightening" of American public schools. Throughout the book, the authors explore how various public and private realms operate to try to silence queer voices, and they discuss ways…

  5. Nanostructure devices and fabrication method

    NASA Technical Reports Server (NTRS)

    Stevens, Ramsey M. (Inventor)

    2009-01-01

    An ion flux is directed to a carbon nanotube to permanently shape, straighten and/or bend the carbon nanotube into a desired configuration. Such carbon nanotubes have many properties that make them ideal as probes for Scanning Probe Microscopy and many other applications.

  6. 40 CFR 63.5385 - How do I measure the quantity of finish applied to the leather?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) of this section: (i) Locate the flow sensor and other necessary equipment such as straightening vanes in or as close to a position that provides a representative flow. (ii) Use a flow sensor with a... distributions due to upstream and downstream disturbances. (iv) Conduct a flow sensor calibration check at...

  7. 40 CFR 63.1452 - What are my monitoring requirements?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... exempted from the requirements of this paragraph (a). (1) Install the monitoring device, associated sensor(s), and recording equipment according to the manufacturers' specifications. Locate the sensor(s... flow sensor and other necessary equipment such as straightening vanes in a position that provides...

  8. Cyclical fluvial response caused by rechannelization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Yalobusha River system in northwestern Mississippi was channelized ca. 1967 to enhance channel capacity and alleviate flooding. Design of the channelization project allowed the enlarged, straightened channel to discharge into an unmodified sinuous reach, and the junction between these two geomet...

  9. Taking Care of Your Hair

    MedlinePlus

    ... chemical treatments: Relaxers. Relaxers (straighteners) work by breaking chemical bonds in curly hair. Relaxers containing lye can cause skin irritation and hair breakage. Although "no lye" relaxers may cause less ... before a chemical relaxing treatment can increase these risks. And don' ...

  10. Hair--Curvy or Straight; Cosmetology 1: 9205.04.

    ERIC Educational Resources Information Center

    Dade County Public Schools, Miami, FL.

    Permanent curling and straightening require a thorough understanding of hair. Through diligent study and practice the student prepares for a profitable part of a beauty career. The course requires 135 hours of classroom-laboratory instruction. Those entering must have mastered the skills of shaping and conditioning hair. On completion of the…

  11. Tennis Rackets and the Parallel Axis Theorem

    ERIC Educational Resources Information Center

    Christie, Derek

    2014-01-01

    This simple experiment uses an unusual graph straightening exercise to confirm the parallel axis theorem for an irregular object. Along the way, it estimates experimental values for g and the moment of inertia of a tennis racket. We use Excel to find a 95% confidence interval for the true values.

  12. View north of inside machine shop 36; shop floor accommodates ...

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

    View north of inside machine shop 36; shop floor accommodates lathes capable of machining a cylinder 60 inches in diameter and 75 feet long; other equipment includes horizontal and vertical jig borders, hydraulic tube straighteners and other equipment for precision machining of large ship components. - Naval Base Philadelphia-Philadelphia Naval Shipyard, Structure Shop, League Island, Philadelphia, Philadelphia County, PA

  13. 40 CFR 63.1452 - What are my monitoring requirements?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... exempted from the requirements of this paragraph (a). (1) Install the monitoring device, associated sensor(s), and recording equipment according to the manufacturers' specifications. Locate the sensor(s... flow sensor and other necessary equipment such as straightening vanes in a position that provides...

  14. Effects of channelization on fish biomass in river ecosystems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Channel straightening of a meandering river is a common trigger of channel incision which may results in stream bank destabilization. Several of the rivers in the upland portion of the Yazoo River Basin have subjected channelization resulting in changes in the physical and geomorphological charact...

  15. TROPHIC STRUCTURE, REPRODUCTIVE SUCCESS, AND GROWTH RATE OF FISHES IN A NATURAL AND MODIFIED HEADWATER STREAM

    EPA Science Inventory

    The impact of removing riparian vegetation, channel straightening, and fluctuations in flow regime on trophic structure, reproductive success, and growth rate of fishes was assessed in a natural (Jordan Creek(JC)) and modified (Big Ditch(BD)) headwater stream in eastcentral Illin...

  16. 49 CFR 572.85 - Lumbar spine flexure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... rotate from its initial position in accordance with Figure No. 18 of § 572.21 (49 CFR part 572) by 40 degrees at a force level of not less than 18 pounds and not more than 22 pounds, and straighten upon... Lumbar spine flexure. (a) When subjected to continuously applied force in accordance with paragraph...

  17. 49 CFR 173.28 - Reuse, reconditioning and remanufacture of packagings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    .... Editorial Note: For Federal Register citations affecting § 173.28, see the List of CFR Sections Affected...) straightened and sealed, and all non-integral gaskets replaced: and (iii) Inspecting after cleaning but before...-integral gaskets and closure devices with new or refurbished parts, and cushioning and cushioning...

  18. Crouzon Syndrome (Craniofacial Dysostosis)

    MedlinePlus

    ... between the upper and lower jaws). Dental and plastic surgery specialists monitor facial growth and correct deformities. The ... normally. Orthodontics, to straighten the teeth, and jaw surgery, to place the ... in childhood, the teens or even the adult years. These are complicated ...

  19. Another Vision: THe Church Model of Education Administration (EA).

    ERIC Educational Resources Information Center

    Coleman, Donald G.; And Others

    In 1987 and again in 1988, the National Commission on Excellence in Educational Administration report catalogued a litany of sins committed by educational administration faculties and by institutions of higher education; however, the reports did little to straighten educational administration's crooked halo. Included among the past attempts at…

  20. Scanning Electron Microscopy Study of Hair Shaft Damage Secondary to Cosmetic Treatments of the Hair

    PubMed Central

    Kaliyadan, Feroze; Gosai, BB; Al Melhim, Walid Naief; Feroze, Kaberi; Qureshi, Habib Ahmad; Ibrahim, Sayed; Kuruvilla, Joel

    2016-01-01

    Introduction and Background: Cosmetic procedures for hair, such as bleaching, dyeing, and straightening, are commonly used around the world. It has been suggested that excessive use of such procedures can cause damage to the hair shaft. We aimed to assess hair shaft changes using scanning electron microscopy (SEM) in female volunteers who frequently use hair treatment procedures such as bleaching, dyeing, or straightening. Methods: A cross-sectional, controlled study in a sample of 25 female volunteers (19 study group and 6 controls) in the age group of 18–45 years. The study group was composed of volunteers who regularly used different cosmetic hair treatment procedures such as bleaching, dyeing, and straightening (any one of these or a combination). The control group had never used any specific hair treatment procedure. The hair shaft damage as seen on SEM was assessed using a standardized scoring system and compared among the two groups statistically. The hair shafts were also examined clinically and with light microscopy. Results: No significant differences were seen between the test and control groups with regard to normal clinical examination and light microscopy findings. A higher degree of hair shaft damage was evident under SEM in the study group as compared to the control group. This difference was statistically significant. Conclusions: Regular use of procedures such as bleaching, dyeing, or straightening can lead to subtle changes in the hair shaft which can be detected early by SEM. PMID:27601867

  1. Bilingual Vocational Training Program. Auto Body Repair. Module 2.0: Tools and Equipment.

    ERIC Educational Resources Information Center

    Northern New Mexico Community Coll., El Rito.

    This module on tools and equipment is the second of four (CE 028 303-306) in the auto body repair course of a bilingual vocational training program. The course is designed to furnish theoretical and laboratory experience in welding, metal straightening, metal finishing, painting, and use of power and hand tools. Module objectives are for students…

  2. Gravitropism and phototropism of oat coleoptiles: Post-tropic autostraightening and tissue shrinkage during tropism

    NASA Astrophysics Data System (ADS)

    Tarui, Y.; Iino, M.

    1999-01-01

    We measured changes in length on the two opposite sides of the red-light-grown oat (Avena sativa L.) coleoptiles subjected to either gravitropic or phototropic stimulation and subsequently rotated on a horizontal clinostat. The length measurement was conducted using three 5 mm-long zones delimited by ink markers from the tip. Curvature of each zone was analyzed from the length difference between the two sides. Gravitropism was induced by displacing the seedling from the vertical by 30° or 90° for 25 min. Phototropism was induced by exposing the coleoptile to unilateral blue light for 30 s, which provided a fluence (1.0 μmol m-2) optimal for the pulse-induced positive phototropism or a lower, suboptimal fluence (0.03 μmol m-2). After negatively gravitropic bending, the upper two zones straightened rapidly at either displacement angle. After positively phototropic bending, straightening occurred, but only in the top zone and at the lower fluence. The upper two zones straightened rapidly, however, when bilateral blue light (30 s; 15 μmol m-2 from either direction) was applied 25 min after unilateral stimulation at the higher fluence. Bilateral blue light alone induced no curvature. These results confirm that the straightening of gravitropically bent coleoptiles is autonomic, and suggest that a similar autonomic response participates in the straightening of phototropically bent coleoptiles. Suppression of elongation on the concave side of the coleoptile mainly accounted for gravitropic and phototropic curvatures. The concave side of the top zone shrank during both tropisms. This shrinkage progressed at a high rate from the beginning of curvature response, suggesting that a drop in turgor pressure is the main and direct cause of the shrinkage.

  3. Gravitropism and phototropism of oat coleoptiles: post-tropic autostraightening and tissue shrinkage during tropism.

    PubMed

    Tarui, Y; Iino, M

    1999-01-01

    We measured changes in length on the two opposite sides of the red-light-grown oat (Avena sativa L.) coleoptiles subjected to either gravitropic or phototropic stimulation and subsequently rotated on a horizontal clinostat. The length measurement was conducted using three 5 mm-long zones delimited by ink markers from the tip. Curvature of each zone was analyzed from the length difference between the two sides. Gravitropism was induced by displacing the seedling from the vertical by 30 degrees or 90 degrees for 25 min. Phototropism was induced by exposing the coleoptile to unilateral blue light for 30 s, which provided a fluence (1.0 micromoles m-2) optimal for the pulse-induced positive phototropism or a lower, suboptimal fluence (0.03 micromoles m-2). After negatively gravitropic bending, the upper two zones straightened rapidly at either displacement angle. After positively phototropic bending, straightening occurred, but only in the top zone and at the lower fluence. The upper two zones straightened rapidly, however, when bilateral blue light (30 s; 15 micromoles m-2 from either direction) was applied 25 min after unilateral stimulation at the higher fluence. Bilateral blue light alone induced no curvature. These results confirm that the straightening of gravitropically bent coleoptiles is autonomic, and suggest that a similar autonomic response participates in the straightening of phototropically bent coleoptiles. Suppression of elongation on the concave side of the coleoptile mainly accounted for gravitropic and phototropic curvatures. The concave side of the top zone shrank during both tropisms. This shrinkage progressed at a high rate from the beginning of curvature response, suggesting that a drop in turgor pressure is the main and direct cause of the shrinkage. PMID:11542618

  4. Application of CFD to Explain Anomalous Stall Behavior of the SSME Flowmeter

    NASA Technical Reports Server (NTRS)

    Ascoli, E.; Clever, W.; Hadid, A.; Lynch, E. D.; Stewart, M.; Lee, K.

    1999-01-01

    The Space Shuttle Main Engine (SSME) Fuel Flowmeter is located in the duct between the low and high pressure fuel turbopumps. In the flowmeter the rotation rate of a 4-blade rotor positioned downstream of two flow straighteners is employed to measure the engine fuel flow rate and thereby control the engine mixture ratio via the engine controller. Hence, inaccurate operation of the flowmeter could have serious consequences for SSME engine operation and performance, forcing, for example, tanking of extra fuel to allow for inaccurate flowmeter measurement. Since the current flight flowmeter configuration was incorporated into the SSME in the early eighties, some anomalies in flowmeter behavior have been observed. The initial flowmeter incorporated an "egg crate" design for the two flow straighteners which turn the duct flow to make it more uniform and parallel after it has come out of the 90 degree bend just upstream of the flowmeter.

  5. [Peyronie's disease: diagnostics and therapy].

    PubMed

    Hauptmann, A; Diemer, T; Weidner, W

    2011-05-01

    Peyronie's disease is a benign disorder of the penis but the etiology is still unknown. A wound healing disorder after repetitive microtraumatic lesions with inelastic scar formation of the tunica albuginea potentially leads to the typical symptoms of penile plaque formation, penile pain, deviation and erectile dysfunction. A non-surgical therapy based on a clear pathophysiology does not exist although the benefit of several conservative treatment options is under discussion. In the stable stage of the disease patients with Peyronie's disease frequently undergo penile surgery. Depending on the deviation angle, the penile length and the erectile dysfunction different straightening surgery can be performed. This article provides an overview of the natural history of the disease and describes present conservative management strategies and common surgical techniques for penile straightening. PMID:21557048

  6. Axial Pump

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J., Jr. (Inventor); Akkerman, James W. (Inventor); Aber, Gregory S. (Inventor); VanDamm, George Arthur (Inventor); Bacak, James W. (Inventor); Svejkovsky, Paul A. (Inventor); Benkowski, Robert J. (Inventor)

    1997-01-01

    A rotary blood pump includes a pump housing for receiving a flow straightener, a rotor mounted on rotor bearings and having an inducer portion and an impeller portion, and a diffuser. The entrance angle, outlet angle, axial and radial clearances of blades associated with the flow straightener, inducer portion, impeller portion and diffuser are optimized to minimize hemolysis while maintaining pump efficiency. The rotor bearing includes a bearing chamber that is filled with cross-linked blood or other bio-compatible material. A back emf integrated circuit regulates rotor operation and a microcomputer may be used to control one or more back emf integrated circuits. A plurality of magnets are disposed in each of a plurality of impeller blades with a small air gap. A stator may be axially adjusted on the pump housing to absorb bearing load and maximize pump efficiency.

  7. Rotary blood pump

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J. (Inventor); Akkerman, James W. (Inventor); Aber, Greg S. (Inventor); Vandamm, George A. (Inventor); Bacak, James W. (Inventor); Svejkovsky, Paul A. (Inventor); Benkowski, Robert J. (Inventor)

    1993-01-01

    A rotary blood pump is presented. The pump includes a pump housing for receiving a flow straightener, a rotor mounted on rotor bearings and having an inducer portion and an impeller portion, and a diffuser. The entrance angle, outlet angle, axial, and radial clearances of the blades associated with the flow straightener, inducer portion, impeller portion, and diffuser are optimized to minimize hemolysis while maintaining pump efficiency. The rotor bearing includes a bearing chamber that is filled with crosslinked blood or other bio-compatible material. A back emf integrated circuit regulates rotor operation and a microcomputer may be used to control one or more back emf integrated circuits. A plurality of magnets are disposed in each of a plurality of impeller blades with a small air gap. A stator may be axially adjusted on the pump housing to absorb bearing load and maximize pump efficiency.

  8. Rotary Blood Pump

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J., Jr. (Inventor); Akkerman, James W. (Inventor); Aber, Gregory S. (Inventor); VanDamm, George A. (Inventor); Bacak, James W. (Inventor); Svejkovsky, Paul A. (Inventor); Benkowski, Robert J. (Inventor)

    1996-01-01

    A rotary blood pump includes a pump housing for receiving a flow straightener, a rotor mounted on rotor bearings and having an inducer portion and an impeller portion, and a diffuser. The entrance angle, outlet angle, axial and radial clearances of blades associated with the flow straightener, inducer portion, impeller portion and diffuser are optimized to minimize hemolysis while maintaining pump efficiency. The rotor bearing includes a bearing chamber that is filled with cross-linked blood or other bio-compatible material. A back emf integrated circuit regulates rotor operation and a microcomputer may be used to control one or more back emf integrated circuits. A plurality of magnets are disposed in each of a plurality of impeller blades with a small air gap. A stator may be axially adjusted on the pump housing to absorb bearing load and maximize pump efficiency.

  9. ORTHOPEDIC LEG BRACE

    NASA Technical Reports Server (NTRS)

    Myers, William Neil (Inventor)

    2005-01-01

    Knee braces generally have been rigid in both the knee bending direction and in the knee straightening direction unless a manually operated release is incorporated in them to allow the knee to bend. Desirably a braced knee joint should effectively duplicate the compound, complex, actions of a normal knee. The key to knee braces is the knee joint housing. The housing herein carries a number of cam action pawls. with teeth adapted to engage the internal teeth of a ratchet ring mounted in the housing. Cam action return springs and the shape of the cam action pawl teeth allow rotation of the ratchet ring in a leg straightening direction while still supporting a load. The leg can then be extended during walking while at the same time being prevented by the cam action pawls from buckling in the knee bending direction.

  10. Clinical and anthropological perspectives on chemical relaxing of afro-textured hair.

    PubMed

    Aryiku, S A; Salam, A; Dadzie, O E; Jablonski, N G

    2015-09-01

    The culturally engrained practice of 'relaxing' afro-textured hair has been linked with hair and scalp disorders. Herein, we discuss the evolution of human hair types, focusing in particular on afro-textured hair. We explore the biological features of this hair type, and discuss the different methods employed to straighten afro-textured hair, focusing in particular on chemical straightening. We also examine clinical, anthropological, and psychological issues associated with this latter practice. Examples of common scalp pathologies associated with chronic hair relaxing, such as alopecia, hair breakage, caustic burns and irritant contact dermatitis, are also highlighted. The data presented herein should enable clinicians to engage in culturally appropriate discussions with their patients about issues of appearance and conformity. PMID:25764359

  11. Growth Distribution during Phototropism of Arabidopsis thaliana Seedlings.

    PubMed Central

    Orbovic, V.; Poff, K. L.

    1993-01-01

    The elongation rates of two opposite sides of hypocotyls of Arabidopsis thaliana seedlings were measured during phototropism by using an infrared imaging system. In first positive phototropism, second positive phototropism, and red light-enhanced first positive phototropism, curvature toward the light source was the result of an increase in the rate of elongation of the shaded side and a decrease in the rate of elongation of the lighted side of the seedlings. The phase of straightening that followed maximum curvature resulted from a decrease in the elongation rate of the shaded side and an increase in the elongation rate of the lighted side. These data for the three types of blue light-induced phototropism tested in this study and for the phase of straightening are all clearly consistent with the growth rate changes predicted by the Cholodny-Went theory. PMID:12231922

  12. Surgery of the nasal septum.

    PubMed

    Mlynski, Gunter

    2006-11-01

    Long-term results after septoplasty are not satisfactory. Apart from a recurrence of deviation, there are various reasons for this: false preoperative analysis, complete straightening of the septum, and a disturbed nasal cycle. Preoperative functional diagnostics with a combination of rhinoresistometry, acoustic rhinometry, and long-term rhinoflowmetry are necessary for differentiating between "physiological" and "pathological" septal deviations and recognizing other causes for obstruction. The surgical procedure of septoplasty includes approach, mobilization, resection, reposition, and finally reconstruction of all three layers. The goal of the operation should not be complete straightening of the nasal septum. The space between the septum and turbinates is of utmost importance. It should not be enlarged as much as possible; rather, it must be shaped in such a way as to allow freely congestion and decongestion reciprocal on the two sides during the nasal cycle. PMID:17131264

  13. The aerodynamic performance of several flow control devices for internal flow systems

    NASA Technical Reports Server (NTRS)

    Eckert, W. T.; Wettlaufer, B. M.; Mort, K. W.

    1982-01-01

    An experimental reseach and development program was undertaken to develop and document new flow-control devices for use in the major modifications to the 40 by 80 Foot wind tunnel at Ames Research Center. These devices, which are applicable to other facilities as well, included grid-type and quasi-two-dimensional flow straighteners, louver panels for valving, and turning-vane cascades with net turning angles from 0 deg to 90 deg. The tests were conducted at model scale over a Reynolds number range from 2 x 100,000 to 17 x 100,000, based on chord. The results showed quantitatively the performance benefits of faired, low-blockage, smooth-surface straightener systems, and the advantages of curved turning-vanes with hinge-line gaps sealed and a preferred chord-to-gap ratio between 2.5 and 3.0 for 45 deg or 90 deg turns.

  14. Open-cell Stent Deployment across the Wide Neck of a Large Middle Cerebral Aneurysm Using the Stent Anchor Technique

    PubMed Central

    Shibukawa, Masaaki; Tani, Itaru; Oki, Shuichi; Kurisu, Kaoru

    2016-01-01

    We describe a case of successful open-cell stent deployment across the wide neck of a large middle cerebral artery aneurysm using the stent anchor technique. A microcatheter was looped through the aneurysm and navigated into a distal vessel across the aneurysm neck. Although the loop of the microcatheter in the aneurysm straightened as it was gently withdrawn, the microcatheter again protruded into the aneurysm by open-cell stent navigation. The stent was partially deployed in a vessel distal to the aneurysm neck, withdrawn slowly to straighten the loop of the microcatheter in the aneurysm, and completely deployed across the aneurysm neck. After successful stent deployment, stent-assisted coil embolization was performed without complications. The stent anchor technique was successfully used to deploy an open-cell stent across the aneurysm neck in this case of microcatheter protrusion into the aneurysm during stent navigation. PMID:27114965

  15. Inward spread of activation in vertebrate muscle fibres

    PubMed Central

    González-Serratos, H.

    1971-01-01

    1. A method for detecting the activation of individual myofibrils or groups of myofibrils within an isolated muscle fibre is described. It consists in making all the myofibrils wavy by setting the fibre in gelatine and compressing it longitudinally; active shortening of myofibrils can then be recognized by the straightening out of the waves. 2. The time course of this straightening during a twitch was found by high-speed ciné micrography. 3. There is a delay of activation between the superficial and central myofibrils, from which the velocity of inward spread of activation can be found. 4. This velocity has a Q10 of 2, and is about 7 cm/sec at 20° C. The mechanism of the inward spread of activation is discussed. 5. On relaxation the waves reappear, showing that there is a spontaneous elongation of the myofibrils. ImagesPlate 1Plate 2Plate 3Plate 4 PMID:5557071

  16. [Axis deviation of lumbar spine due to abdominal expanding lesions in children (author's transl)].

    PubMed

    Ponhold, W; Jürgenssen, O A; Balzar, E; Poplavsky, K; Püspök, R

    1981-01-01

    The deviation of the physiologic lordosis of the lumbar spine is described in 40 cases of abdominal expanding lesions. One can find a lumbar kyphosis between L2 and L4 in retroperitoneal and a straightening between Th12 and L2 in intraperitoneal lesions. The evidence of a deviation of the lumbar axis is an indirect sign for further localisation of the tumor. PMID:7254891

  17. Evaluation and Treatment of a Ureterosciatic Hernia Causing Hydronephrosis and Renal Colic

    PubMed Central

    Salari, Keyan; Yura, Emily M.; Harisinghani, Mukesh

    2015-01-01

    Abstract An 87-year-old female presented with complaints of intermittent severe right renal colic. CT imaging demonstrated a ureterosciatic hernia and moderate hydronephrosis proximal to the portion of the ureter that was herniated through the sciatic foramen. A retrograde pyelogram demonstrated a transition point in the ureter at the location of the hernia. A ureteral stent was placed resulting in straightening of the ureter, resolution of hydronephrosis, and complete resolution of the patient's symptoms.

  18. Experimental investigation of inlet flow-control cascades for the NFAC 80- by 120-foot Indraft Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Van Aken, Johannes M.; Scheller, Nina M.

    1988-01-01

    The present investigation of aerodynamic performance for various inlet cascade configurations of an indraft wind tunnel with a short inlet and a low contraction ratio has given attention to the effects of inlet wall shape, antiturbulence screens, and horizontal flow straighteners on test-section flow quality. It is found that an inlet cascade with a tailored vane-splay distribution, antiturbulence screen, and horizontal splitters, will both yield good test section flow quality and furnish isolation from atmospheric winds and turbulence.

  19. Overcoming Robot-Arm Joint Singularities

    NASA Technical Reports Server (NTRS)

    Barker, L. K.; Houck, J. A.

    1986-01-01

    Kinematic equations allow arm to pass smoothly through singular region. Report discusses mathematical singularities in equations of robotarm control. Operator commands robot arm to move in direction relative to its own axis system by specifying velocity in that direction. Velocity command then resolved into individual-joint rotational velocities in robot arm to effect motion. However, usual resolved-rate equations become singular when robot arm is straightened.

  20. On quasi-periodic solutions of the 2+1 dimensional Caudrey-Dodd-Gibbon-Kotera-Sawada equation

    NASA Astrophysics Data System (ADS)

    Cao, Cewen; Wu, Yongtang; Geng, Xianguo

    1999-05-01

    The 2+1 dimensional Caudrey-Dodd-Gibbon-Kotera-Sawada equation is decomposed into systems of integrable ordinary differential equations resorting to the nonlinearization of Lax pairs. The Abel-Jacobi coordinates are introduced to straighten the flows, from which quasi-periodic solutions of the 2+1 dimensional Caudrey-Dodd-Gibbon-Kotera-Sawada equation are obtained in terms of Riemann theta functions.

  1. SPRING DRIVEN ACTUATING MECHANISM FOR NUCLEAR REACTOR CONTROL

    DOEpatents

    Bevilacqua, F.; Uecker, D.F.; Groh, E.F.

    1962-01-23

    l962. rod in a nuclear reactor to shut it down. The control rod or an extension thereof is wound on a drum as it is withdrawn from the reactor. When an emergency occurs requiring the reactor to be shut down, the drum is released so as to be free to rotate, and the tendency of the control rod or its extension coiled on the drum to straighten itself is used for quickly returning the control rod to the reactor. (AEC)

  2. Analysis of data on absorption in the northern part of the milky way

    NASA Technical Reports Server (NTRS)

    Polishchuk, E. P.

    1973-01-01

    The values of absorption for different galactic longitudes are obtained on the basis of star cluster data. It is found that the distance up to the point, where the straightening of the absorption distribution curve begins, depends on the limiting magnitude of the catalogue and the density of absorbing matter near the sun. The picture of absorbing matter distribution in the northern part of the Milky Way is given.

  3. GPOs do some explaining. Concerned about conflicts of interest, a Senate judiciary committee gives GPOs 90 days to create a code of conduct.

    PubMed

    Becker, Cinda

    2002-05-01

    Premier Chairman and CEO Richard Norling and Novation President Mark McKenna feared the worst before a U.S. Senate subcommittee last week. Equipment markers' allegations that their innovative products are barred from the marketplace by deals between GPOs and longtime large suppliers led to the hearing. But instead of lowering the boom, the panel gave the companies a grace period to straighten up. PMID:12037925

  4. Minimally invasive veneers: current state of the art

    PubMed Central

    Vanlıoğlu, Burçin Akoğlu; Kulak-Özkan, Yasemin

    2014-01-01

    Ceramic veneers are considered a conservative solution for patients requiring improvement of the shape, color, or position of their anterior teeth. Ceramic veneers have been extensively and successfully used to mask intrinsic staining, to give the appearance of straightening, and to correct minor malformations of anterior teeth without the removal of substantial amounts of sound tooth substance. The current literature was reviewed to search for the most important parameters determining the long-term success and correct application of ceramic veneers. PMID:25506248

  5. Explicit quasi-periodic solutions of the Vakhnenko equation

    NASA Astrophysics Data System (ADS)

    Zhai, Yunyun; Geng, Xianguo; He, Guoliang

    2014-05-01

    The trigonal curve associated with the Vakhnenko equation is introduced by using the Lax matrix for the nth stationary positive flow. Based on the theory of the trigonal curve and the properties of the three kinds of Abel differentials, the Riemann theta function representation for the Baker-Akhiezer function is derived, from which the straightening out of flows in the Jacobian variety is exactly given through the Abel maps. We finally arrive at quasi-periodic solutions of the Vakhnenko equation.

  6. On the violation of Bell’s inequality for all non-product quantum states

    NASA Astrophysics Data System (ADS)

    Cafaro, Carlo; Ali, Sean Alan; Giffin, Adom

    2016-06-01

    We present an explicit reexamination of Gisin’s 1991 original proof concerning the violation of Bell’s inequality for any pure entangled state of two-particle systems. Given the relevance of Gisin’s work, our analysis is motivated by pedagogical reasons and allows the straightening of a few mathematical points in the original proof that in no way change the physical conclusions reached by Gisin.

  7. Minimally invasive veneers: current state of the art.

    PubMed

    Vanlıoğlu, Burçin Akoğlu; Kulak-Özkan, Yasemin

    2014-01-01

    Ceramic veneers are considered a conservative solution for patients requiring improvement of the shape, color, or position of their anterior teeth. Ceramic veneers have been extensively and successfully used to mask intrinsic staining, to give the appearance of straightening, and to correct minor malformations of anterior teeth without the removal of substantial amounts of sound tooth substance. The current literature was reviewed to search for the most important parameters determining the long-term success and correct application of ceramic veneers. PMID:25506248

  8. Hamiltonian formalism in the equilibrium problem for a plasma with islands

    SciTech Connect

    Skovoroda, A. A.

    2011-08-15

    Hamiltonian formalism is applied to the equilibrium problem for a plasma with islands by using an analogy between the equilibrium problem for a plasma with one island and the nonlinear mechanics of a physical pendulum. A relationship is established between magnetic flux coordinates with straightened magnetic field lines and the action-angle variables. The flux and current representations of a magnetic field with islands are obtained, and the solution to the equilibrium problem for a narrow island is presented.

  9. A model of channel response in disturbed alluvial channels

    USGS Publications Warehouse

    Simon, A.

    1989-01-01

    Dredging and straightening of alluvial channels between 1959 and 1978 in West Tennessee caused a series of morphologic changes along modified reaches and tributary streams. Degradation occurred for 10 to 15 years at sites upstream of the area of maximum disturbance and lowered bed-levels by as much as 6.1 m. Following degradation, reaches upstream of the area of maximum disturbance experienced a secondary aggradation phase in response to excessive incision and gradient reduction. -from Author

  10. Accordion phenomenon of the hepatic artery: mimicker of vasospasm or intimal injury

    PubMed Central

    Koyama, Yoshinori; Tsushima, Yoshito

    2016-01-01

    The accordion phenomenon occurs because of mechanical distortion of a straightened vessel during coronary and vascular interventions. To date, however, this phenomenon has not been reported in vessels of the upper abdomen. We therefore describe the accordion phenomenon of the hepatic artery during transarterial chemoembolization seen while treating a liver tumor. As the accordion phenomenon is now known to involve hepatic arteries, it should be differentiated from vascular complications such as vasospasm or intimal injury. PMID:27570635

  11. Tarantula myosin free head regulatory light chain phosphorylation stiffens N-terminal extension, releasing it and blocking its docking back.

    PubMed

    Alamo, Lorenzo; Li, Xiaochuan Edward; Espinoza-Fonseca, L Michel; Pinto, Antonio; Thomas, David D; Lehman, William; Padrón, Raúl

    2015-08-01

    Molecular dynamics simulations of smooth and striated muscle myosin regulatory light chain (RLC) N-terminal extension (NTE) showed that diphosphorylation induces a disorder-to-order transition. Our goal here was to further explore the effects of mono- and diphosphorylation on the straightening and rigidification of the tarantula myosin RLC NTE. For that we used MD simulations followed by persistence length analysis to explore the consequences of secondary and tertiary structure changes occurring on RLC NTE following phosphorylation. Static and dynamic persistence length analysis of tarantula RLC NTE peptides suggest that diphosphorylation produces an important 24-fold straightening and a 16-fold rigidification of the RLC NTE, while monophosphorylation has a less profound effect. This new information on myosin structural mechanics, not fully revealed by previous EM and MD studies, add support to a cooperative phosphorylation-dependent activation mechanism as proposed for the tarantula thick filament. Our results suggest that the RLC NTE straightening and rigidification after Ser45 phosphorylation leads to a release of the constitutively Ser35 monophosphorylated free head swaying away from the thick filament shaft. This is so because the stiffened diphosphorylated RLC NTE would hinder the docking back of the free head after swaying away, becoming released and mobile and unable to recover its original interacting position on activation. PMID:26038302

  12. A simple technique for removing the Nuss bar with one stabilizer: the lateral approach.

    PubMed

    Varela, Patricio; Romanini, Moria Victoria; Asquasciati, Caterina; Torre, Michele

    2010-02-01

    The removal of the substernal bar after the Nuss operation is not always an easy and fast maneuver. Only a few different technical solutions have been described. In the original Nuss technique, the patient was lying on dorsal decubitus and rotated on the side during the procedure. The Noguchi technique avoids the rotation of the patient, but requires two incisions and straightening of the bar before pulling it out the thorax. Recently, another technique was proposed, avoiding the need of straightening the bar, but it is feasible only if two operative beds in a large operative room are available. We propose another approach for the removal of the bar: The patient is lying on the lateral decubitus, only one incision is performed, and the bar is pulled out along the thoracic wall. Twenty-one bars were removed by using the present approach without any complications. The advantages of our approach on the previous techniques are the single incision, no need of rotating the patient, straightening the bar, or having two operative beds. Our approach is not feasible when metallic stabilizers have been used on both sides, but in our experience, this was not necessary in order to stabilize the bar. PMID:19432531

  13. Analysis of Internal Cracks in Continuous Casting Slabs with Soft Reduction

    NASA Astrophysics Data System (ADS)

    Wang, Bo; Zhang, Jiongming; Xiao, Chao; Wang, Shunxi; Song, Wei

    2016-03-01

    The formation of internal cracks in continuous casting slabs is mainly attributed to the strain status and microsegregation near the solidifying front of the slabs. By analyzing the internal cracks of medium carbon microalloy steel, the obtained conclusions are that C, P, S, etc. enrich in dendrites and exist in grain boundaries, but these are just the internal causes, and the root cracking causes the tensile stress of solidification front. When the slab passes through the straightening segments, the liquid core thickness is large, and the liquid steel in the space of columnar crystals is not completely frozen. Therefore, the reduction effect of rollers results in the strain of solidification front exceeding the critical value. However, the corresponding strain in the arc and horizontal segments does not exceed this critical value, so the solidification front in the straightening segments would be much easy to crack. The statistics analysis shows that after soft reduction and straightening process are separately carried out, the occurrence rate of intermediate cracks is reduced by 41.3%.

  14. Spatial organization of the gravitropic response in plants: applicability of the revised local curvature distribution model to Triticum aestivum coleoptiles.

    PubMed

    Meskauskas, A; Jurkoniene, S; Moore, D

    1999-08-01

    The revised local curvature distribution model, which provides accurate computer simulations of the gravitropic response of mushroom stems, was found to produce accurate simulations of the gravitropic reaction of wheat (Triticum aestivum) coleoptiles. The key feature of the mathematical model that enables it to approach universality of application is the assumption that the stem has an autonomic straightening reaction (curvature compensation or 'autotropism'). In the model, the local bending rate for any segment of the organ is determined by the difference between the 'bending signal' (generated by the gravitropic signal perception system) and a 'straightening signal' (which is proportional to the local curvature of the segment). The model reveals three major differences between the gravitropic reactions of wheat coleoptiles and Coprinus mushroom stems. First, in Coprinus, the capacity for autonomic straightening is much more concentrated in the apical region of the stem. Second, local perception of the gravitropic signal, which is necessary for exact simulation in Coprinus, is not needed in wheat coleoptiles (the corresponding constant in the model can be set to zero). Third, the transmission rate of the gravitropic signal is about seven times faster in wheat coleoptiles than in the mushroom stem. Thus, we demonstrate that a single model, depending on the values given to its parameters, is able to simulate the spatial organization of the gravitropic reaction of wheat coleoptiles and Coprinus mushroom stems. The model promises to be a valuable predictive tool in guiding future research into the gravitropic reaction of axial organs of all types. PMID:11542912

  15. Root Canal Shaping by Single-File Systems and Rotary Instruments: a Laboratory Study

    PubMed Central

    Bane, Khaly; Faye, Babacar; Sarr, Mouhamed; Niang, Seydina O; Ndiaye, Diouma; Machtou, Pierre

    2015-01-01

    Introduction: The aim of this study was to compare the shaping ability of two single-file systems and conventional rotary instruments in severely curved root canals of extracted human molars. Methods and Materials: Mesiobuccal canals of 120 mandibular molars with angles of curvature ranging between 25° and 35° and radii of curvature from 5 to 9 mm, were divided into three groups (n=40). In each group the canals were instrumented with either WaveOne (W), Reciproc (R) or ProTaper (P). The time required for canal shaping and the frequency of broken instruments were recorded. The standardized pre and post-instrumentation radiographs were taken to determine changes in working length (WL) and straightening of canal curvature. The presence of blockage or perforation was also evaluated. Data were analyzed using the one-way analysis of variance (ANOVA) and post-hoc Tukey’s test. The level of significance was set at 0.05. Results: Both single-instrument systems reduced the canal preparation time by approximately 50% (P<0.05). No incidence of broken instruments from single-file systems was reported; however, two F2 instruments in the P group were broken (P<0.05). Reduction in WL and straightening of canal curvature was observed in all three systems with the highest scores belonging to P system (P<0.05). No case of blockage or perforation was found during shaping in any group. Conclusion: Single-file systems shaped curved canals with substantial saving in time and a significant decrease in incidence of instrument separation, change in WL, and straightening of canal curvature. PMID:25834600

  16. Righting response of artificially inclined maritime pine (Pinus pinaster) saplings to wind loading.

    PubMed

    Berthier, Stephane; Stokes, Alexia

    2006-01-01

    To determine if trees respond to dynamic and static loading in the same manner, 2-year-old maritime pine (Pinus pinaster Ait.) trees were subjected to different types of mechanical loading in the field. One block of trees (the control) were kept in pots and planted in the field at an angle of 0 or 45 degrees to the vertical. A similar block of leaning potted trees was planted nearby and subjected to frequent, unilateral wind loading for a period of 1 s every 2 min. Half the leaning trees were oriented toward the direction of wind loading and half were oriented along the axis of wind loading. The stem profile was measured three times during the growing season to quantify the rate of stem straightening. Compression wood formation and stem shape were measured in all plants. No differences in mean height or diameter were observed between blocks and all leaning trees straightened, but not at the same rate. Although no difference in the rate of apical straightening occurred between control and wind-treated trees, the righting response of the basal part of the stem of leaning trees subjected to wind was four times greater than that of leaning trees without wind. No differences in the righting response were observed between leaning trees growing toward and trees growing away from the source of wind. No significant differences in compression wood formation were found between control trees and wind-treated trees, indicating that other factors must determine the reorientation rate of leaning trees. Results are discussed with reference to the quality of compression wood in conifers and the mechanotransductive pathway in plants. PMID:16203716

  17. Atomistic Model of Physical Ageing in Se-rich As-Se Glasses

    SciTech Connect

    Golovchak,R.; Shpotyuk, O.; Kozdras, A.; Bureau, B.; Vlcek, M.; Ganjoo, A.; Jain, H.

    2007-01-01

    Thermal, optical, X-ray excited and magnetic methods were used to develop a microstructural model of physical ageing in Se-rich glasses. The glass composition As10Se90, possessing a typical cross-linked chain structure, was chosen as a model object for the investigations. The effect of physical ageing in this glass was revealed by differential scanning calorimetry, whereas the corresponding changes in its atomic arrangement were studied by extended X-ray absorption fine structure, Raman and solid-state 77Se nuclear magnetic resonance spectroscopy. Straightening-shrinkage processes are shown to be responsible for the physical ageing in this Se-rich As-Se glass.

  18. Dynamics of flexible fibers in shear flow

    NASA Astrophysics Data System (ADS)

    Słowicka, Agnieszka M.; Wajnryb, Eligiusz; Ekiel-JeŻewska, Maria L.

    2015-09-01

    Dynamics of flexible non-Brownian fibers in shear flow at low-Reynolds-number are analyzed numerically for a wide range of the ratios A of the fiber bending force to the viscous drag force. Initially, the fibers are aligned with the flow, and later they move in the plane perpendicular to the flow vorticity. A surprisingly rich spectrum of different modes is observed when the value of A is systematically changed, with sharp transitions between coiled and straightening out modes, period-doubling bifurcations from periodic to migrating solutions, irregular dynamics, and chaos.

  19. High Average Power Laser Gain Medium With Low Optical Distortion Using A Transverse Flowing Liquid Host

    DOEpatents

    Comaskey, Brian J.; Ault, Earl R.; Kuklo, Thomas C.

    2005-07-05

    A high average power, low optical distortion laser gain media is based on a flowing liquid media. A diode laser pumping device with tailored irradiance excites the laser active atom, ion or molecule within the liquid media. A laser active component of the liquid media exhibits energy storage times longer than or comparable to the thermal optical response time of the liquid. A circulation system that provides a closed loop for mixing and circulating the lasing liquid into and out of the optical cavity includes a pump, a diffuser, and a heat exchanger. A liquid flow gain cell includes flow straighteners and flow channel compression.

  20. Dynamics of flexible fibers in shear flow.

    PubMed

    Słowicka, Agnieszka M; Wajnryb, Eligiusz; Ekiel-Jeżewska, Maria L

    2015-09-28

    Dynamics of flexible non-Brownian fibers in shear flow at low-Reynolds-number are analyzed numerically for a wide range of the ratios A of the fiber bending force to the viscous drag force. Initially, the fibers are aligned with the flow, and later they move in the plane perpendicular to the flow vorticity. A surprisingly rich spectrum of different modes is observed when the value of A is systematically changed, with sharp transitions between coiled and straightening out modes, period-doubling bifurcations from periodic to migrating solutions, irregular dynamics, and chaos. PMID:26429038

  1. Brazilian keratin hair treatment: a review.

    PubMed

    Weathersby, Courtney; McMichael, Amy

    2013-06-01

    Brazilian keratin treatments are widely available products that are used by women all over the world to straighten hair. Marketers of these products claim that the keratin treatments render naturally curly hair more manageable and frizz-free while enhancing color and shine, giving the hair a healthier appearance. Although widely used, there have been virtually no reports of adverse side effects. Unfortunately, many of the products that are applied by salon professionals contain formaldehyde or its derivatives and are being marketed as safe. PMID:23725308

  2. Nematic field transfer in a two-dimensional protein fibril assembly.

    PubMed

    Jordens, Sophia; Schwenke, Konrad; Usov, Ivan; Del Gado, Emanuela; Mezzenga, Raffaele

    2016-02-14

    We perform Atomic Force Microscopy and numerical simulations of a bimodal solution containing long, semiflexible β-lactoglobulin fibrils and short, flexible β-lactoglobulin linear aggregates at an air-water interface. Short aggregates orient perpendicular to fibrils at very short distances and preferentially parallel at intermediate distances. At even larger distances an isotropic distribution is observed. Parallel ordering coincides with aggregate stretching: by straightening, small aggregates are able to approach the fibrils within a distance smaller than their radius of gyration. These findings contribute to the understanding of how anisotropic interactions are transferred in two-dimensional bimodal nematic fields of biopolymers at liquid interfaces. PMID:26738771

  3. Flow quality studies of the NASA Lewis Research Center 8- by 6-foot supersonic/9- by 15-foot Low Speed Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Arrington, E. A.; Pickett, Mark T.

    1992-01-01

    A series of studies were conducted to determine the existing flow quality in the NASA Lewis 8 by 6 Foot Supersonic/9 by 15 Foot Low Speed Wind Tunnel. The information gathered from these studies was used to determine the types and designs of flow manipulators which can be installed to improve overall tunnel flow quality and efficiency. Such manipulators include honeycomb flow straighteners, turbulence reduction screens, corner turning vanes, and acoustic treatments. The types of measurements, instrumentation, and results obtained from experiments conducted at several locations throughout the tunnel loop are described.

  4. Flow quality studies of the NASA Lewis Research Center 8- by 6-foot supersonic/9- by 15-foot low speed wind tunnel

    NASA Technical Reports Server (NTRS)

    Arrington, E. Allen; Pickett, Mark T.

    1992-01-01

    A series of studies were conducted to determine the existing flow quality in the NASA Lewis 8 by 6 Foot Supersonic/9 by 15 Foot Low speed Wind Tunnel. The information gathered from these studies was used to determine the types and designs of flow manipulators which can be installed to improve overall tunnel flow quality and efficiency. Such manipulators include honeycomb flow straighteners, turbulence reduction screens, corner turning vanes, and acoustic treatments. The types of measurements, instrumentation, and results obtained from experiments conducted at several locations throughout the tunnel loop are described.

  5. Hair cosmetics: an overview.

    PubMed

    Gavazzoni Dias, Maria Fernanda Reis

    2015-01-01

    Hair cosmetics are an important tool that helps to increase patient's adhesion to alopecia and scalp treatments. This article reviews the formulations and the mode of action of hair cosmetics: Shampoos, conditioners, hair straightening products, hair dyes and henna; regarding their prescription and safetiness. The dermatologist's knowledge of hair care products, their use, and their possible side effects can extend to an understanding of cosmetic resources and help dermatologists to better treat hair and scalp conditions according to the diversity of hair types and ethnicity. PMID:25878443

  6. Hair care and dyeing.

    PubMed

    Draelos, Zoe Diana

    2015-01-01

    Alopecia can be effectively camouflaged or worsened through the use of hair care techniques and dyeing. Proper hair care, involving hair styling and the use of mild shampoos and body-building conditioners, can amplify thinning scalp hair; however, chemical processing, including hair dyeing, permanent waving, and hair straightening, can encourage further hair loss through breakage. Many patients suffering from alopecia attempt to improve their hair through extensive manipulation, which only increases problems. Frequent haircuts to minimize split ends, accompanied by gentle handling of the fragile fibers, is best. This chapter offers the dermatologist insight into hair care recommendations for the alopecia patient. PMID:26370650

  7. Undulating membrane structure under mixed extensional-shear flow

    NASA Astrophysics Data System (ADS)

    Idziak, S. H. J.; Welch, S. E.; Kisilak, M.; Mugford, C.; Potvin, G.; Veldhuis, L.; Sirota, E. B.

    2001-10-01

    We report on studies using a new X-ray extensional flow cell to examine, for the first time, the structure of undulating lamellar lyotropic liquid crystal systems under extensional flow. The extensional component of the flow profile produced within this cell causes the lamellae to orient. We find that, although the intermembrane spacing does not change at low flow rates, it suddenly decreases after a critical flow rate has been attained due to the stretching and straightening of the lamellae. The effects of the shear component of flow on this oriented system have been examined in the context of a theoretical model developed by Ramaswamy.

  8. The application of trigonal curve to the Mikhailov-Shabat-Sokolov flows

    NASA Astrophysics Data System (ADS)

    He, Guoliang; Geng, Xianguo; Wu, Lihua

    2016-08-01

    Resorting to the characteristic polynomial of Lax matrix for the Mikhailov-Shabat-Sokolov hierarchy associated with a {3 × 3} matrix spectral problem, we introduce a trigonal curve, from which we deduce the associated Baker-Akhiezer function, meromorphic functions and Dubrovin-type equations. The straightening out of the Mikhailov-Shabat-Sokolov flows is exactly given through the Abel map. On the basis of these results and the theory of trigonal curve, we obtain the explicit theta function representations of the Baker-Akhiezer function, the meromorphic functions, and in particular, that of solutions for the entire Mikhailov-Shabat-Sokolov hierarchy.

  9. A note on the quasi-periodic solutions of the modified Boussinesq hierarchy

    NASA Astrophysics Data System (ADS)

    Wu, Lihua; He, Guoliang; Geng, Xianguo

    2015-10-01

    Based on the theory of trigonal curve and the properties of three kinds of the Abel differentials on it, we deduce the explicit theta function representations of the Baker-Akhiezer function and the meromorphic function associated with the modified Boussinesq hierarchy. The modified Boussinesq flows are straightened using the Abel map and the Lagrange interpolation formula. The explicit theta function representations of solutions for the entire modified Boussinesq hierarchy are constructed with the aid of the asymptotic properties and the algebro-geometric characters of the meromorphic function.

  10. Repositioning of Misplaced Central Venous Catheter with Saline Injection Under C-Arm Imaging

    PubMed Central

    Gautam, Parshotam Lal; Jain, Krishan; Monga, Hitika

    2015-01-01

    Malposition of central venous catheter is a well known technical complication. Misplaced catheter often requires reinsertion for proper placement of the catheter in the superior vena cava (SVC) to support safe delivery of care and minimize complications. But reinsertion exposes the patient once again to risks of complications related to the procedure including potential of misplacement. Literature describes only a few techniques for repositioning a misplaced central venous catheter (CVC). We tried old simple method of saline injection with force under image intensifier using hydrostatic force of intravenous fluid to straighten the CVC. We could successfully reposition two misplaced CVC’s using this method. PMID:26816974

  11. An imaging and analysis toolset for the study of Caenorhabditis elegans neurodevelopment

    NASA Astrophysics Data System (ADS)

    Christensen, Ryan; Bokinsky, Alexandra; Santella, Anthony; Wu, Yicong; Marquina, Javier; Kovacevic, Ismar; Kumar, Abhishek; Winter, Peter; McCreedy, Evan; Mohler, William; Bao, Zhirong; Colón-Ramos, Daniel; Shroff, Hari

    2015-03-01

    How an entire nervous system develops remains mysterious. We have developed a light-sheet microscope system to examine neurodevelopment in C. elegans embryos. Our system creates overlapping light sheets from two orthogonally positioned objectives, enabling imaging from the first cell division to hatching (~14 hours) with 350 nm isotropic resolution. We have also developed computer algorithms to computationally straighten nematode embryos, facilitating data comparison and combination from multiple animals. We plan to use these tools to create an atlas showing the position and morphology of all neurons in the developing embryo.

  12. Finite-band solutions of the coupled dispersionless hierarchy

    NASA Astrophysics Data System (ADS)

    Li, Zhu

    2016-08-01

    The coupled dispersionless hierarchy is derived with the help of the zero curvature equation. Based on the Lax matrix, we introduce an algebraic curve {{ K }}n of arithmetic genus n, from which we establish the corresponding meromorphic function ϕ, the Baker–Akhiezer function {\\varphi }1, and Dubrovin-type equations. The straightening out of all the flows is given under the Abel–Jacobi coordinates. Using the asymptotic properties of ϕ and {\\varphi }1, we obtain the explicit theta function representations of the meromorphic function ϕ, the Baker–Akhiezer function {\\varphi }1 and of solutions for the whole hierarchy.

  13. Turbulent dispersion via fan-generated flows

    PubMed Central

    Halloran, Siobhan K.; Wexler, Anthony S.; Ristenpart, William D.

    2014-01-01

    Turbulent dispersion of passive scalar quantities has been extensively studied in wind tunnel settings, where the flow is carefully conditioned using flow straighteners and grids. Much less is known about turbulent dispersion in the “unconditioned” flows generated by fans that are ubiquitous in indoor environments, despite the importance of these flows to pathogen and contaminant transport. Here, we demonstrate that a point source of scalars released into an airflow generated by an axial fan yields a plume whose width is invariant with respect to the fan speed. The results point toward a useful simplification in modeling of disease and pollution spread via fan-generated flows. PMID:24932096

  14. Double-diffusive fingering instability of a surfactant-glycerine-water drop in water

    NASA Astrophysics Data System (ADS)

    Kötter, K.; Markus, M.

    2001-09-01

    We present an experimental setup that allows easy visualization of single fingers formed by double diffusive convection. This setup consists of a drop (containing water and two solutes) that is injected at the bottom of a dish filled with water. The gravity-driven expansion of the drop induces a toroidal bulk flow of the surrounding water. This flow straightens and confines the fingers horizontally and quasi two-dimensionally. An extremely low diffusion coefficient of one of the two solutes (a surfactant in our case) causes unusually stable configurations. This stability is robust within a wide range of concentrations. Wavelength measurements agree well with theoretical estimations.

  15. Dynamics of flexible fibers in shear flow

    SciTech Connect

    Słowicka, Agnieszka M.; Wajnryb, Eligiusz; Ekiel-Jeżewska, Maria L.

    2015-09-28

    Dynamics of flexible non-Brownian fibers in shear flow at low-Reynolds-number are analyzed numerically for a wide range of the ratios A of the fiber bending force to the viscous drag force. Initially, the fibers are aligned with the flow, and later they move in the plane perpendicular to the flow vorticity. A surprisingly rich spectrum of different modes is observed when the value of A is systematically changed, with sharp transitions between coiled and straightening out modes, period-doubling bifurcations from periodic to migrating solutions, irregular dynamics, and chaos.

  16. Surgical orthodontic correction of mandibular laterognathism

    PubMed Central

    Singh, Harpreet; Srivastava, Dhirendra; Kapoor, Pranav; Sharma, Poonam

    2016-01-01

    This case report describes the successful treatment of a patient with mandibular laterognathism and associated facial asymmetry with combined surgical orthodontic approach. After 7 months of presurgical orthodontic treatment, intraoral vertical ramus osteotomy, and straightening genioplasty were performed as two step surgeries to reposition the deviated mandible and chin, respectively. The total active treatment period was 14 months. After surgical orthodontic treatment, significant improvement in occlusion, masticatory function, and facial appearance was discernible. Posttreatment records at 3 years showed stable results with good occlusion. PMID:27127755

  17. Hair Cosmetics: An Overview

    PubMed Central

    Gavazzoni Dias, Maria Fernanda Reis

    2015-01-01

    Hair cosmetics are an important tool that helps to increase patient's adhesion to alopecia and scalp treatments. This article reviews the formulations and the mode of action of hair cosmetics: Shampoos, conditioners, hair straightening products, hair dyes and henna; regarding their prescription and safetiness. The dermatologist's knowledge of hair care products, their use, and their possible side effects can extend to an understanding of cosmetic resources and help dermatologists to better treat hair and scalp conditions according to the diversity of hair types and ethnicity. PMID:25878443

  18. Finite-difference solution for turbulent swirling compressible flow in axisymmetric ducts with struts

    NASA Technical Reports Server (NTRS)

    Anderson, O. L.

    1974-01-01

    A finite-difference procedure for computing the turbulent, swirling, compressible flow in axisymmetric ducts is described. Arbitrary distributions of heat and mass transfer at the boundaries can be treated, and the effects of struts, inlet guide vanes, and flow straightening vanes can be calculated. The calculation procedure is programmed in FORTRAN 4 and has operated successfully on the UNIVAC 1108, IBM 360, and CDC 6600 computers. The analysis which forms the basis of the procedure, a detailed description of the computer program, and the input/output formats are presented. The results of sample calculations performed with the computer program are compared with experimental data.

  19. Cosmetic and amino acid analysis of the effects of lye and no-lye relaxer treatment on adult black female South African hair.

    PubMed

    Mamabolo, Thabisile; Agyei, Nana M; Summers, Beverley

    2013-01-01

    Surveys indicate that many South African women use relaxers to straighten their hair for cosmetic reasons, which can damage the hair and scalp. The objective of this study was to assess the effects of treating hair with two types of relaxers: Product A (a lye relaxer, sodium hydroxide base) and Product B (a no-lye relaxer, guanidine hydroxide base). Five adult black female South African subjects were used for the study that was divided into two parts. The first part used a half-head study design in a clinical study in which the researcher and the subjects visually assessed various hair quality parameters before and after relaxer treatment. Product B was assessed to perform better (p = 0.032) than Product A in terms of hair straightening. The second part of the study involved hair amino acid analysis by reversed-phase high performance liquid chromatography. There was a decrease in the amount of cystine [Median (range) g/100 g hair] after treatment with both Product A [7.8 (2.5-9.9), p = 0.086] and Product B [4.0 (2.9-4.8), p = 0.005] compared to before treatment [9.1 (6.4-11.9)]; this decrease was greater (p = 0.085) for Product B. Reduction in cystine content was consistent with increased straightness. Product B (the no-lye relaxer) was found to be more effective and safer to use. PMID:23931091

  20. Low-relief landscape modeling with human activities

    NASA Astrophysics Data System (ADS)

    Yan, Q.; Kumar, P.; Anders, A. M.

    2015-12-01

    Intensively managed landscapes (IMLs) in the Midwestern United States have been shaped by repeated glacial events over geologic time scales followed by rapid human modifications for agriculture and artificial drainage that were overlaid on extremely low gradient stream networks. These landscapes are heavily modified by agriculture, artificial drainage, deforestation, urbanization, and wetland destruction. Channel head extension and periodic dredging for channel straightening not only strongly affected hydrologic and geomorphologic response, but also fundamentally alter the energy consumption in the whole river basin. However, it is unclear how the landscape consumes and responds to the extra energy from human activities. Therefore, we evaluate the present-day dynamics of river network from the perspective of of geomorphic equilibrium, hydrological response, and the rate of energy dissipation. Then, we simulate the landscape evolution to discover the tendency of the system. We find that channel head extension and straightening increases the rate of energy dissipation and pushes the river network further away from equilibrium condition. From our numerical model simulation, extending and maintaining the ditches in the river network can cause large ridge migration, river network redistribution, and enlargement of the drainage basin area. Our research demonstrates how the river basin responds to human activities in glaciated landscape, and how it is likely to behave with artificial modifications on the topography in the future. We attribute the legacy to drainage basin reorganization and theorized that humans can have a lasting impact on the landscape even after active management has ceased.

  1. Crystal nucleation mechanism in melts of short polymer chains under quiescent conditions and under shear flow

    NASA Astrophysics Data System (ADS)

    Anwar, Muhammad; Berryman, Joshua T.; Schilling, Tanja

    2014-09-01

    We present a molecular dynamics simulation study of crystal nucleation from undercooled melts of n-alkanes, and we identify the molecular mechanism of homogeneous crystal nucleation under quiescent conditions and under shear flow. We compare results for n-eicosane (C20) and n-pentacontahectane (C150), i.e., one system below the entanglement length and one above, at 20%-30% undercooling. Under quiescent conditions, we observe that entanglement does not have an effect on the nucleation mechanism. For both chain lengths, the chains first align and then straighten locally, then the local density increases and finally positional ordering sets in. At low shear rates the nucleation mechanism is the same as under quiescent conditions, while at high shear rates the chains align and straighten at the same time. We report on the effects of shear rate and temperature on the nucleation rates and estimate the critical shear rates, beyond which the nucleation rates increase with the shear rate. In agreement with previous experimental observation and theoretical work, we find that the critical shear rate corresponds to a Weissenberg number of order 1. Finally, we show that the viscosity of the system is not affected by the crystalline nuclei.

  2. Molecular Dynamics Simulations of the Cx26 Hemichannel: Insights into Voltage-Dependent Loop-Gating

    PubMed Central

    Kwon, Taekyung; Roux, Benoît; Jo, Sunhwan; Klauda, Jeffery B.; Harris, Andrew L.; Bargiello, Thaddeus A.

    2012-01-01

    Loop-gating is one of two voltage-dependent mechanisms that regulate the open probability of connexin channels. The loop-gate permeability barrier is formed by a segment of the first extracellular loop (E1) (the parahelix) and appears to be accompanied by straightening of the bend angle between E1 and the first transmembrane domain (TM1). Here, all-atom molecular dynamics simulations are used to identify and characterize interacting van der Waals and electrostatic networks that stabilize the parahelices and TM1/E1 bend angles of the open Cx26 hemichannel. Dynamic fluctuations in an electrostatic network in each subunit are directly linked to the stability of parahelix structure and TM1/E1 bend angle in adjacent subunits. The electrostatic network includes charged residues that are pore-lining and thus positioned to be voltage sensors. We propose that the transition to the closed state is initiated by voltage-driven disruption of the networks that stabilize the open-state parahelix configuration, allowing the parahelix to protrude into the channel pore to form the loop-gate barrier. Straightening of the TM1/E1 bend appears to be a consequence of the reorganization of the interacting networks that accompany the conformational change of the parahelix. The electrostatic network extends across subunit boundaries, suggesting a concerted gating mechanism. PMID:22455917

  3. Ultra High-Resolution In vivo Computed Tomography Imaging of Mouse Cerebrovasculature Using a Long Circulating Blood Pool Contrast Agent

    PubMed Central

    Starosolski, Zbigniew; Villamizar, Carlos A.; Rendon, David; Paldino, Michael J.; Milewicz, Dianna M.; Ghaghada, Ketan B.; Annapragada, Ananth V.

    2015-01-01

    Abnormalities in the cerebrovascular system play a central role in many neurologic diseases. The on-going expansion of rodent models of human cerebrovascular diseases and the need to use these models to understand disease progression and treatment has amplified the need for reproducible non-invasive imaging methods for high-resolution visualization of the complete cerebral vasculature. In this study, we present methods for in vivo high-resolution (19 μm isotropic) computed tomography imaging of complete mouse brain vasculature. This technique enabled 3D visualization of large cerebrovascular networks, including the Circle of Willis. Blood vessels as small as 40 μm were clearly delineated. ACTA2 mutations in humans cause cerebrovascular defects, including abnormally straightened arteries and a moyamoya-like arteriopathy characterized by bilateral narrowing of the internal carotid artery and stenosis of many large arteries. In vivo imaging studies performed in a mouse model of Acta2 mutations demonstrated the utility of this method for studying vascular morphometric changes that are practically impossible to identify using current histological methods. Specifically, the technique demonstrated changes in the width of the Circle of Willis, straightening of cerebral arteries and arterial stenoses. We believe the use of imaging methods described here will contribute substantially to the study of rodent cerebrovasculature. PMID:25985192

  4. Generating hand dysaesthesiae: the “GHD phenomenon” – straight to the diagnosis

    PubMed Central

    Lonergan, Roisin; Gorman, Grainne; Alexander, Michael D; Killeen, Ronan; de Blacam, Catherine; Tubridy, Niall

    2009-01-01

    Two Irish women presented with difficulty in completion of hair straightening, limited by upper limb dysaesthesiae due to claudication or brachial plexus entrapment induced by sustained shoulder abduction beyond 90 degrees. The first described arm pain precipitated by elevation and sustained abduction above shoulder level, particularly while using her GHD hair-straightener. Elevated arm stress test was positive and a left cervical rib was seen on chest x ray. Neurogenic thoracic outlet syndrome (TOS) was diagnosed and the cervical rib was resected. The second described arm tingling and weakness when performing tasks involving shoulder abduction and elevation, limiting GHD use to 10 min before having to rest. Upper limb blood pressure and pulses were undetectable. Erythrocyte sedimentation rate was elevated and flow on radial Doppler disappeared on abduction and elevation of each arm. A CT pulmonary angiography demonstrated features of Takayasu’s arteritis. Vascular TOS was diagnosed. Symptoms resolved with corticosteroids, followed by long-term immunosuppression and anti-coagulation. PMID:21686996

  5. Active motion assisted by correlated stochastic torques.

    PubMed

    Weber, Christian; Radtke, Paul K; Schimansky-Geier, Lutz; Hänggi, Peter

    2011-07-01

    The stochastic dynamics of an active particle undergoing a constant speed and additionally driven by an overall fluctuating torque is investigated. The random torque forces are expressed by a stochastic differential equation for the angular dynamics of the particle determining the orientation of motion. In addition to a constant torque, the particle is supplemented by random torques, which are modeled as an Ornstein-Uhlenbeck process with given correlation time τ(c). These nonvanishing correlations cause a persistence of the particles' trajectories and a change of the effective spatial diffusion coefficient. We discuss the mean square displacement as a function of the correlation time and the noise intensity and detect a nonmonotonic dependence of the effective diffusion coefficient with respect to both correlation time and noise strength. A maximal diffusion behavior is obtained if the correlated angular noise straightens the curved trajectories, interrupted by small pirouettes, whereby the correlated noise amplifies a straightening of the curved trajectories caused by the constant torque. PMID:21867138

  6. Relaxation of bending stresses and the reversibility of residual stresses in amorphous soft magnetic alloys

    SciTech Connect

    Kekalo, I. B.; Mogil’nikov, P. S.

    2015-06-15

    The reversibility of residual bending stresses is revealed in ribbon samples of cobalt- and iron-based amorphous alloys Co{sub 69}Fe{sub 3.7}Cr{sub 3.8}Si{sub 12.5}B{sub 11} and Fe{sub 57}Co{sub 31}Si{sub 2.9}B{sub 9.1}: the ribbons that are free of applied stresses and bent under the action of residual stresses become completely or incompletely straight upon annealing at the initial temperatures. The influence of annealing on the relaxation of bending stresses is studied. Preliminary annealing is found to sharply decrease the relaxation rate of bending stresses, and the initial stage of fast relaxation of these stresses is absent. Complete straightening of preliminarily annealed ribbons is shown to occur at significantly higher temperatures than that of the initial ribbons. Incomplete straightening of the ribbons is explained by the fact that bending stresses relaxation at high annealing temperatures proceeds due to both reversible anelastic deformation and viscous flow, which is a fully irreversible process. Incomplete reversibility is also caused by irreversible processes, such as the release of excess free volume and clustering (detected by small-angle X-ray scattering). The revealed differences in the relaxation processes that occur in the cobalt- and iron-based amorphous alloys are discussed in terms of different atomic diffusion mobilities in these alloys.

  7. Design and prototyping of a large capacity high frequency pulse tube

    NASA Astrophysics Data System (ADS)

    Ercolani, E.; Poncet, J. M.; Charles, I.; Duband, L.; Tanchon, J.; Trollier, T.; Ravex, A.

    2008-09-01

    This document describes the design and the prototyping performed at CEA/SBT in partnership with AIR LIQUIDE of a high frequency large cooling power pulse tube. Driven at 58 Hz by a 7.5 kW flexure bearing pressure wave generator, this system provides a net heat lift of 210 W at 65 K. The phase shift is obtained by an inertance and a buffer volume. This type of cryogenic cooler can be used for on site gas liquefaction or drilling site and for high temperature superconductivity power device cooling (transmission lines, large generators, fault current limiters). In this paper, we focus on two essential points, the regenerator and the flow straightener. The regenerator is a key component for good performance of the pulse tube cooler. It must have a large thermal inertia, a low dead volume, a good heat transfer gas/matrix and at the same time, small pressure drop. In the present case and unlike typical moderate cooling power pulse tubes, the regenerator is very compact. However, the resulting conductive losses remain negligible compared to the cooling power targeted. The goal of the flow straightener is to avoid as much as possible any jet stream effect and to guarantee the uniformity of the velocity field at both ends of the pulse tube. Indeed multi-dimensional flow effects can significantly impact the performances of the machine.

  8. Quantification of interaction and topological parameters of polyisoprene star polymers under good solvent conditions

    NASA Astrophysics Data System (ADS)

    Rai, Durgesh K.; Beaucage, Gregory; Ratkanthwar, Kedar; Beaucage, Peter; Ramachandran, Ramnath; Hadjichristidis, Nikos

    2016-05-01

    Mass fractal scaling, reflected in the mass fractal dimension df, is independently impacted by topology, reflected in the connectivity dimension c , and by tortuosity, reflected in the minimum dimension dmin. The mass fractal dimension is related to these other dimensions by df=c dmin . Branched fractal structures have a higher mass fractal dimension compared to linear structures due to a higher c , and extended structures have a lower dimension compared to convoluted self-avoiding and Gaussian walks due to a lower dmin. It is found, in this work, that macromolecules in thermodynamic equilibrium display a fixed mass fractal dimension df under good solvent conditions, regardless of chain topology. These equilibrium structures accommodate changes in chain topology such as branching c by a decrease in chain tortuosity dmin. Symmetric star polymers are used to understand the structure of complex macromolecular topologies. A recently published hybrid Unified scattering function accounts for interarm correlations in symmetric star polymers along with polymer-solvent interaction for chains of arbitrary scaling dimension. Dilute solutions of linear, three-arm and six-arm polyisoprene stars are studied under good solvent conditions in deuterated p -xylene. Reduced chain tortuosity can be viewed as steric straightening of the arms. Steric effects for star topologies are quantified, and it is found that steric straightening of arms is more significant for lower-molecular-weight arms. The observation of constant df is explained through a modification of Flory-Krigbaum theory for branched polymers.

  9. Self-propelling microswimmer made of a bi-faced hydrogel

    NASA Astrophysics Data System (ADS)

    Alexeev, Alexander; Nikolov, Svetoslav V.; Yeh, Peter

    2014-03-01

    We use dissipative particle dynamics to design a new self-propelling microswimmer. Our microswimmer features a simple design and represents an X-shaped gel layer. The gel has two distinct sides or facets: one facet is responsive and swells when an external stimulus is applied, whereas the other facet is passive. We show that when an external stimulus is applied periodically, the swimmer propels itself unidirectionally in a highly viscous fluid. The propulsion is associated with periodic shape changes. When the stimulus is applied, the responsive facet swells, inducing internal stresses in the gel causing both lateral expansion and bending of the microswimmer. When the external stimulus is removed, the responsive layer contracts, and elastic forces cause the microswimmer to straighten and to recover the initial shape. The combination of the sequential expansion, bending, contraction, and straightening produces a time irreversible motion pattern leading to net propulsion at low Reynolds number. We examine how the swimming speed can be enhanced by selecting material properties and geometry of the swimmer. This work is supported by NSF CAREER award DMR-1255288.

  10. Minimally invasive scoliosis treatment with a Ho:YAG laser

    NASA Astrophysics Data System (ADS)

    Rumpf, Christian G.; Lang, Robert D.; Goetz, Marcus H.

    2000-11-01

    Today most surgical treatment of spinal deformations is concentrated on invasive mechanical techniques with long operation times and major effects on the patient's mobility. The proposed minimally invasive technique using laser light for tissue ablation offers a possibility of gentle scoliosis treatment. It is thought that an early removal of the epiphysial growth zone on the convex side over several vertebrae results in a straightening of the spine. In a first evaluation, four different laser systems including argon ion, Nd:YAG (Q-switched), Nd:YAG (cw), and Ho:YAG laser were compared with respect to thermal damage to adjacent tissue, ablation rates, efficiency and laser handling. For in-vivo investigation, fresh lamb spine was used. Comparison showed that the Ho:YAG laser is the most appropriate laser for the given goal, providing efficient photoablation with moderate thermal effects on the adjacent tissue. In a second step the proposed minimally invasive operation technique was performed in in-vivo experiments on young foxhounds using 3D- thoracoscopic operation techniques. During these operations temperature mapping was done using fiber-optic fluorescent probes. After 12 months of normal growth the animals were sacrificed and x-ray as well as MRI was performed on the spine. First results show a positive effect of scoliotic growth in two cases. Being able to produce a scoliosis by hemiepiphysiodesis on the vertebra, It is thought that this technique is successful for a straightening of the spine on patients with scoliosis.

  11. Antioxidants have a rapid and long-lasting effect on neuritic abnormalities in APP:PS1 mice.

    PubMed

    Garcia-Alloza, Monica; Borrelli, Laura A; Hyman, Bradley T; Bacskai, Brian J

    2010-12-01

    Senile plaques are a major pathological hallmark of Alzheimer's disease (AD). Compelling evidence suggests that senile plaques lead to structural alterations of neuronal processes and that local toxicity may be mediated by increased oxidative stress. Anti-oxidant therapy can alleviate the neuronal abnormalities in APP mice, but the time-course of this beneficial effect is unknown. We used multiphoton microscopy to assess in vivo the characteristics of antioxidant treatment on senile plaques and neurites in AD model mice (APPswe/PS1dE9). We observed that α-phenyl-N-tert-butyl nitrone (PBN), Ginkgo biloba extract (EGb 761) and Trolox had no effect on the size of existing senile plaques. However, all anti-oxidants had a straightening effect on curved neurites. This effect was detected as soon as 4 days after commencing the treatment, and was maintained after 1 month of daily treatment, with no further increase in the effect. The straightening of neurites persisted 15 days after stopping the treatment. These data indicate that neuronal plasticity is fast and still active in adult animals, and suggest that amelioration of the neuritic distortions associated with senile plaques with antioxidants is both rapid and long lasting. PMID:19124175

  12. Phase errors and predicted spectral performance of a prototype undulator

    SciTech Connect

    Dejus, R.J.; Vassrman, I.; Moog, E.R.; Gluskin, E.

    1994-08-01

    A prototype undulator has been used to study different magnetic end-configurations and shimming techniques for straightening the beam trajectory. Field distributions obtained by Hall probe measurements were analyzed in terms of trajectory, phase errors, and on-axis brightness for the purpose of correlating predicted spectral intensity with the calculated phase errors. Two device configurations were analyzed. One configuration had a full-strength first magnet at each end and the next-to-last pole was recessed to make the trajectory through the middle of the undulator parallel to the undulator axis. For the second configuration, the first permanent magnet at each end was replaced by a half-strength magnet to reduce the trajectory displacement and the next-to-last pole was adjusted appropriately, and shims were added to straighten the trajectory. Random magnetic field errors can cause trajectory deviations that will affect the optimum angle for viewing the emitted radiation, and care must be taken to select the appropriate angle when calculating the phase errors. This angle may be calculated from the average trajectory angle evaluated at the location of the poles. For the second configuration, we find an rms phase error of less than 3{degrees} and predict 87% of the ideal value of the on-axis brightness for the third harmonic. We have also analyzed the gap dependence of the phase errors and spectral brightness and have found that the rms phase error remain small at all gap settings.

  13. A review of surgical strategies for penile prosthesis implantation in patients with Peyronie's disease.

    PubMed

    Anaissie, James; Yafi, Faysal A

    2016-06-01

    The introduction of the inflatable penile prosthesis (IPP) has revolutionized the treatment of patients with both Peyronie's disease (PD) and erectile dysfunction (ED). A thorough literature review was performed in order to review the surgical strategies used to treat PD, using the PubMed online database with the keywords "penile prosthesis", "surgical management" and "Peyronie's disease". Patient satisfaction rates of 72-100% and partner satisfaction rates of 89% have been reported in the literature, although strong preoperative education may be needed to prepare patients for risks such as penile shortening, seen in up to 54% of patients. Three-piece IPPs are most commonly used, and when comparing the two most popular models (AMS 700 CX vs. Coloplast Titan), no significant differences were seen in functional outcomes or patient satisfaction. Simple insertion of an IPP has been shown to resolve curvature in 33-90% of patients, but surgeons may often need to also utilize ancillary straightening procedures for residual curvatures. Manual modeling can correct residual curvature with an 86-100% success rate, but with a 4% risk of urethral injury. When the post-modeling residual curvature exceeds 30 degrees, a plaque-releasing incision or plication is recommended to further reduce curvature. Grafting is recommended if the resulting incisional defect is larger than two centimeters. Alternative straightening techniques such as plication prior to IPP insertion, endoscopic plaque resection, the "scratch technique" and bone saw plaque incision have also been described. PMID:27298781

  14. Measuring Outdoor Air Intake Rates into Existing Building

    SciTech Connect

    Fisk, William; Sullivan, Douglas; Cohen, Sebastian; Han, Hwataik

    2009-04-16

    Practical and accurate technologies are needed for continuously measuring and controlling outdoor air (OA) intake rates in commercial building heating, ventilating, and air conditioning (HVAC) systems. This project evaluated two new measurement approaches. Laboratory experiments determined that OA flow rates were measurable with errors generally less than 10 percent using electronic air velocity probes installed between OA intake louver blades or at the outlet face of louvers. High accuracy was maintained with OA flow rates as low as 15 percent of the maximum for the louvers. Thus, with this measurement approach HVAC systems do not need separate OA intakes for minimum OA supply. System calibration parameters are required for each unique combination of louver type and velocity sensor location but calibrations are not necessary for each system installation. The research also determined that the accuracy of measuring OA flow rates with velocity probes located in the duct downstream of the intake louver was not improved by installing honeycomb airflow straighteners upstream of the probes. Errors varied with type of upstream louver, were as high as 100 percent, and were often greater than 25 percent. In conclusion, use of electronic air velocity probes between the blades of OA intake louvers or at the outlet face of louvers is a highly promising means of accurately measuring rates of OA flow into HVAC systems. The use of electronic velocity probes downstream of airflow straighteners is less promising, at least with the relatively small OA HVAC inlet systems employed in this research.

  15. Ho:YAG laser in reshaping tracheal cartilage: a pilot investigation using ex vivo porcine and rabbit cartilage

    NASA Astrophysics Data System (ADS)

    Lam, Anthony; Protsenko, Dmitry E.; Carbone, Nicholas; Li, Chao; Jackson, Ryan; Wong, Brian J.

    2004-07-01

    Stenotic, collapsed, and flow-restricted tracheal airways may result from blunt trauma, chronic infection, and the prolonged endotracheal intubation. This pilot investigation characterizes the degree of shape change produced by Ho:YAG laser (λ=2.12 μm) irradiation of rabbit and pig trachea tissue as a function of laser dosimetry and application protocol. Force displacement curves were generated using fresh lagomorph and porcine tracheal cartilage rings secured in a modified single beam cantilever geometry. These specimens were then irradiated for varying amounts of time and power with the objective of straightening these curved specimens. The degree of shape change was documented photographically. Force and surface temperature were monitored. Confocal microscopy was then used in combination a vital staine ("live-dead assay") to determine the level of viability of straightened cartilage for selected exposure time-power pairs. Laser Cartilage Reshaping of the trachea may provide a new method to treat severe tracheal injuries without the need for classic open surgical techniques. This pilot investigation is the first step toward demonstrating the feasibility of this technique. Long-term, the design of stents combined with laser irradiation may provide a means to alter tracheal shape.

  16. How Cellulose Stretches: Synergism between Covalent and Hydrogen Bonding

    PubMed Central

    2014-01-01

    Cellulose is the most familiar and most abundant strong biopolymer, but the reasons for its outstanding mechanical performance are not well understood. Each glucose unit in a cellulose chain is joined to the next by a covalent C–O–C linkage flanked by two hydrogen bonds. This geometry suggests some form of cooperativity between covalent and hydrogen bonding. Using infrared spectroscopy and X-ray diffraction, we show that mechanical tension straightens out the zigzag conformation of the cellulose chain, with each glucose unit pivoting around a fulcrum at either end. Straightening the chain leads to a small increase in its length and is resisted by one of the flanking hydrogen bonds. This constitutes a simple form of molecular leverage with the covalent structure providing the fulcrum and gives the hydrogen bond an unexpectedly amplified effect on the tensile stiffness of the chain. The principle of molecular leverage can be directly applied to certain other carbohydrate polymers, including the animal polysaccharide chitin. Related but more complex effects are possible in some proteins and nucleic acids. The stiffening of cellulose by this mechanism is, however, in complete contrast to the way in which hydrogen bonding provides toughness combined with extensibility in protein materials like spider silk. PMID:24568640

  17. Applications of Self-Referencing Method to the Virgo Cluster Spirals

    NASA Astrophysics Data System (ADS)

    Chung, Eun Jung; Kim, Hyoryoung; Rhee, Myung-Hyun

    2005-12-01

    Self-referencing method in revised-OTFTOOL is a new method in On-The-Fly(OTF) observation mode. It uses the source free regions of the observed frame as references instead of the OFFs references. We already analyzed and discussed its proprieties and advantages in the previous paper. In this paper, we make a statistical study about the self-referencing method by applying it to OTF mapping data of 27 Virgo spiral galaxies. We found that the self-referencing method solves the crooked baseline problem for every datacube. It straightens the baseline, and conserves the emissions. Compared with other data processing, the median filtering task' mwflt' in AIPS, to use self-referencing method is more effective and safe not only to straighten the baseline but also to conserve the emission. For the strong CO galaxies, the data obtained by self-referencing method shows scarcely any difference from those reduced by conventional OFFs references and AIPS median filtering in the range of uncertainties. Undetected CO emissions in datacubes of conventional OFFs references are also not detected in those of self-referencing method. The self-referencing method is expected to save the observing time and simplify data reduction processes. Besides this, using self-referencing method will offer emission-free references more safely.

  18. Registration of coronary arteries in computed tomography angiography images using Hidden Markov Model.

    PubMed

    Luo, Yuxuan; Feng, Jianjiang; Xu, Miao; Zhou, Jie; Min, James K; Xiong, Guanglei

    2015-08-01

    Computed tomography angiography (CTA) allows for not only diagnosis of coronary artery disease (CAD) with high spatial resolution but also monitoring the remodeling of vessel walls in the progression of CAD. Alignment of coronary arteries in CTA images acquired at different times (with a 3-7 years interval) is required to visualize and analyze the geometric and structural changes quantitatively. Previous work in image registration primarily focused on large anatomical structures and leads to suboptimal results when applying to registration of coronary arteries. In this paper, we develop a novel method to directly align the straightened coronary arteries in the cylindrical coordinate system guided by the extracted centerlines. By using a Hidden Markov Model (HMM), image intensity information from CTA and geometric information of extracted coronary arteries are combined to align coronary arteries. After registration, the pathological features in two straightened coronary arteries can be directly visualized side by side by synchronizing the corresponding cross-sectional slices and circumferential rotation angles. By evaluating with manually labeled landmarks, the average distance error is 1.6 mm. PMID:26736676

  19. On the tear resistance of skin

    NASA Astrophysics Data System (ADS)

    Yang, Wen; Sherman, Vincent R.; Gludovatz, Bernd; Schaible, Eric; Stewart, Polite; Ritchie, Robert O.; Meyers, Marc A.

    2015-03-01

    Tear resistance is of vital importance in the various functions of skin, especially protection from predatorial attack. Here, we mechanistically quantify the extreme tear resistance of skin and identify the underlying structural features, which lead to its sophisticated failure mechanisms. We explain why it is virtually impossible to propagate a tear in rabbit skin, chosen as a model material for the dermis of vertebrates. We express the deformation in terms of four mechanisms of collagen fibril activity in skin under tensile loading that virtually eliminate the possibility of tearing in pre-notched samples: fibril straightening, fibril reorientation towards the tensile direction, elastic stretching and interfibrillar sliding, all of which contribute to the redistribution of the stresses at the notch tip.

  20. Structural dynamics of an actin spring.

    PubMed

    Mahadevan, L; Riera, C S; Shin, Jennifer H

    2011-02-16

    Actin-based motility in cells is usually associated with either polymerization/depolymerization in the presence of cross-linkers or contractility in the presence of myosin motors. Here, we focus on a third distinct mechanism involving actin in motility, seen in the dynamics of an active actin spring that powers the acrosomal reaction of the horseshoe crab (Limulus polyphemus) sperm. During this process, a 60-μm bent and twisted bundle of cross-linked actin uncoils and becomes straight in a few seconds in the presence of Ca(2+). This straightening, which occurs at a constant velocity, allows the acrosome to forcefully penetrate the egg. Synthesizing ultrastructural information with the kinetics, energetics, and imaging of calcium binding allows us to construct a dynamical theory for this mechanochemical engine consistent with our experimental observations. It also illuminates the general mechanism by which energy may be stored in conformational changes and released cooperatively in ordered macromolecular assemblies. PMID:21320427

  1. Automatic Upright Adjustment of Photographs With Robust Camera Calibration.

    PubMed

    Lee, Hyunjoon; Shechtman, Eli; Wang, Jue; Lee, Seungyong

    2014-05-01

    Man-made structures often appear to be distorted in photos captured by casual photographers, as the scene layout often conflicts with how it is expected by human perception. In this paper, we propose an automatic approach for straightening up slanted man-made structures in an input image to improve its perceptual quality. We call this type of correction upright adjustment. We propose a set of criteria for upright adjustment based on human perception studies, and develop an optimization framework which yields an optimal homography for adjustment. We also develop a new optimization-based camera calibration method that performs favorably to previous methods and allows the proposed system to work reliably for a wide range of images. The effectiveness of our system is demonstrated by both quantitative comparisons and qualitative user study. PMID:26353220

  2. Ridge network in crumpled paper.

    PubMed

    Andresen, Christian André; Hansen, Alex; Schmittbuhl, Jean

    2007-08-01

    The network formed by ridges in a straightened sheet of crumpled paper is studied using a laser profilometer. Square sheets of paper were crumpled into balls, unfolded, and their height profile measured. From these profiles the imposed ridges were extracted as networks. Nodes were defined as intersections between ridges, and links as the various ridges connecting the nodes. Many network and spatial properties have been investigated. The tail of the ridge length distribution was found to follow a power law, whereas the shorter ridges followed a log-normal distribution. The degree distribution was found to have an exponentially decaying tail, and the degree correlation was found to be disassortative. The facets created by the ridges and the Voronoi diagram formed by the nodes have also been investigated. PMID:17930105

  3. Probabilistic constitutive law for damage in ligaments.

    PubMed

    Guo, Zheying; De Vita, Raffaella

    2009-11-01

    A new constitutive equation is presented to describe the damage evolution process in parallel-fibered collagenous tissues such as ligaments. The model is formulated by accounting for the fibrous structure of the tissues. The tissue's stress is defined as the average of the collagen fiber's stresses. The fibers are assumed to be undulated and straightened out at different stretches that are randomly defined according to a Weibull distribution. After becoming straight, each collagen fiber is assumed to be linear elastic. Damage is defined as a reduction in collagen fiber's stiffness and occurs at different stretches that are also randomly defined by a Weibull distribution. Due to the lack of experimental data, the predictions of the constitutive equation are analyzed by varying the values of its structural parameters. Moreover, the results are compared with the available stress-strain data in the biomechanics literature that evaluate damage produced by subfailure stretches in rat medial collateral ligaments. PMID:19665914

  4. Thoracic endovascular aortic repair of a severely angulated aorta using a double-wire technique.

    PubMed

    Kawatani, Yohei; Nakamura, Yoshitsugu; Hayashi, Yujiro; Taneichi, Tetsuyoshi; Ito, Yujiro; Kurobe, Hirotsugu; Suda, Yuji; Hori, Takaki

    2016-01-01

    When endovascular treatment is performed, angulation of the access route for a device can make the operative procedure difficult. We encountered a case in which we successfully completed thoracic endovascular aortic repair (TEVAR) in a patient with severely angulated aorta by applying 'double-wire technique'. The patient was an 80-year-old woman. An aneurysm with a 71-mm diameter was observed in the descending aorta. We performed TEVAR. Device delivery could not be achieved by a conventional procedure using one guide wire since the peripheral aorta was severely angulated. Therefore, in addition to a guide wire for main body, a stiff wire and a stiff sheath were introduced to straighten the angulation. The device was successfully introduced and TEVAR was completed. We used the Relay Plus(®) that facilitates tracking through the angulation. The device has a dual structure consisting of a hard sheath and a flexible sheath. We performed TEVAR successfully. PMID:27421301

  5. Nanoscale manipulation of Ge nanowires by ion hammering

    SciTech Connect

    Picraux, Samuel T; Romano, Lucia; Rudawski, Nicholas G; Holzworth, Monta R; Jones, Kevin S; Choi, S G

    2009-01-01

    Nanowires generated considerable interest as nanoscale interconnects and as active components of both electronic and electromechanical devices. However, in many cases, manipulation and modification of nanowires are required to realize their full potential. It is essential, for instance, to control the orientation and positioning of nanowires in some specific applications. This work demonstrates a simple method to reversibly control the shape and the orientation of Ge nanowires by using ion beams. Initially, crystalline nanowires were partially amorphized by 30 keY Ga+-implantation. After amorphization, viscous flow and plastic deformation occurred due to the ion hammering effect, causing the nanowires to bend toward the beam direction. The bending was reversed multiple times by ion-implanting the opposite side of the nanowires, resulting in straightening of the nanowires and subsequent bending in the opposite direction. This ion hammering effect demonstrates the detailed manipulation of nanoscale structures is possible through the use of ion irradiation.

  6. Another Estimate for the Percentage of Partly Embayed Craters in Equilibrium Resurfacing

    NASA Astrophysics Data System (ADS)

    Muinonen, P. J.

    1996-03-01

    When choosing between different scenarios of Venus' resurfacing history, one of the objections against an Equilibrium Resurfacing Model (ERM) is an apparent lack of craters that have suffered a partial embayment by lava flows of outside origin. Any test of ERM so far, be it numeric or analytic in nature, has failed to predict anything even near the observed ~5% of partly embayed craters (PECs) without violating the statistics of crater distribution. This study is mainly based on straightening out as many as possible of the simplifications that have been employed while estimating the statistical implications of the ERM. As a result, the expectation value for PECs falls to less than 10% from previous ~30%.

  7. Peyronie's Reconstruction for Maximum Length and Girth Gain: Geometrical Principles

    PubMed Central

    Egydio, Paulo H.; Sansalone, Salvatore

    2008-01-01

    Peyronie's disease has been associated with penile shortening and some degree of erectile dysfunction. Surgical reconstruction should be based on giving a functional penis, that is, rectifying the penis with rigidity enough to make the sexual intercourse. The procedure should be discussed preoperatively in terms of length and girth reconstruction in order to improve patient satisfaction. The tunical reconstruction for maximum penile length and girth restoration should be based on the maximum length of the dissected neurovascular bundle possible and the application of geometrical principles to define the precise site and size of tunical incision and grafting procedure. As penile rectification and rigidity are required to achieve complete functional restoration of the penis and 20 to 54% of patients experience associated erectile dysfunction, penile straightening alone may not be enough to provide complete functional restoration. Therefore, phosphodiesterase inhibitors, self-injection, or penile prosthesis may need to be added in some cases. PMID:19081785

  8. Preservation of Cavernosal Erectile Function after Soft Penile Prosthesis Implant in Peyronie's Disease: Long-Term Followup

    PubMed Central

    Grasso, Marco; Lania, Caterina; Fortuna, Flavio; Blanco, Salvatore; Piacentini, Igor

    2008-01-01

    The aim of this retrospective study is to evaluate the long-term followup of soft penile SSDA prosthesis, without plaque surgery in the treatment of Peyronie's disease. This study included 12 men with Peyronie's disease who underwent placement of a penile prosthesis. All patients were followed for at least 6 years. Prosthesis straightened the penile shaft in all cases, restoring patient sexual satisfaction. No operative or postoperative complications occurred, and no reoperations were needed. All patients have undergone further examination with basal and dynamic eco color Doppler. The findings are encouraging as the penis preserves the ability to enhance the tumescence and penile girth. We can conclude that SSDA penile prosthesis is safe and effective in Peyronie's disease. PMID:19081839

  9. A Min-Time Analysis of Three Trajectories with Curvature and Nonholonomic Constraints Using a Parallel Parking Criterion

    NASA Astrophysics Data System (ADS)

    Lyon, Douglas

    This paper presents a comparison of three s-shaped curves for parallel parking a car subject to nonholonomic constraints. The comparison is based on the rate at which the car approaches the curb (the parking criterion). The curves (two circular arcs, a cosine curve and a quintic) are shown to accommodate an initial and final position, but only the quintic accommodates initial and final curvature. The time penalty in straightening out the wheels at the maneuver end-points (or midpoint) causes the other curves to be suboptimal. Representative examples of the curves are shown. Also illustrated is the effect of the turning radius of the car on the time required to park it.

  10. Recent Developments in Ground-Borne Noise and Vibration Control

    NASA Astrophysics Data System (ADS)

    Nelson, J. T.

    1996-05-01

    Vibration control provisions available to the transit designer include (among others) precision straightened rail, ballast mats, floating slabs and very soft direct fixation fasteners, in addition to rail grinding, wheel truing, and continuous welded rail. Recently, the Los Angeles Metro has developed specifications for a soft resilient direct fixation fastener to fit the same base dimensions as the standard direct fixation fastener. In San Francisco, low resonance frequency (8 Hz) floating slabs have been constructed to mitigate predicted ground vibration impacts at nearby residential structures. In Atlanta, low resonance frequency loading slabs have been constructed to maintain a low vibration environment in a medical building planned to be built over the subway structure. In Portland and Pasadena, ballast mats have been recommended to control light rail transit ground vibration impacts on housing located at typically 35 feet from the alignment. Each of these provisions are briefly described in view of recent applications at U.S. transit systems.

  11. Spectrum of mucocutaneous manifestations in human immunodeficiency virus-infected patients and its correlation with CD4 lymphocyte count.

    PubMed

    Fernandes, Michelle S; Bhat, Ramesh M

    2015-05-01

    In this study, 100 HIV-positive cases (63 men, 37 women) with skin findings were included. The mean CD4 T cell count was 253 cells/mm(3). A total of 235 dermatological manifestations were seen. The common infectious dermatoses were candidiasis (21%), Staphylococcal skin infections (20%), dermatophytoses (14%) and herpes zoster (6%). Among the non-infectious dermatoses were papular pruritic eruptions (20%), xerosis/ichthyosis (20%) and seborrhoeic dermatitis (16%). Statistically significant association (p < 0.05) with CD4 T cell count was seen in pyodermas, dermatophytoses and papular pruritic eruptions. Adverse drug reactions, diffuse hair loss, straightening of hairs and pigmentary changes were also noted. Although there was an absence of Kaposi's sarcoma in our study, a case of verrucous carcinoma of penis was noted. PMID:25015936

  12. A 22-year follow-up of the nonsurgical expansion of maxillary and mandibular arches in a young adult: Are the outcomes stable, relapsed, or unstable with aging?

    PubMed

    Valladares-Neto, José; Evangelista, Karine; Miranda de Torres, Hianne; Melo Pithon, Matheus; Alves Garcia Santos Silva, Maria

    2016-09-01

    Adult maxillary and mandible arch expansion without a surgical approach can be uncertain when long-term stability is considered. This case report describes the treatment of a 19-year-old woman with an Angle Class I malocclusion with constricted maxillary and mandibular arches. The patient's main complaint was mandibular anterior crowding. The treatment plan included expansion of the mandibular arch concurrent with semirapid maxillary expansion. An edgewise appliance was used to adjust the final occlusion. Smile esthetics and dental alignment were improved without straightening the profile. This outcome was followed up with serial dental casts for 22 years after treatment. At the end of that period, the occlusion and tooth alignment were clinically satisfactory, further supported by mandibular fixed retention. However, the transverse widths were continuously and gradually reduced over time, superposing orthodontic transverse relapse and natural arch constriction caused by aging. PMID:27585782

  13. Functions of plant-specific myosin XI: from intracellular motility to plant postures.

    PubMed

    Ueda, Haruko; Tamura, Kentaro; Hara-Nishimura, Ikuko

    2015-12-01

    The plant-specific protein motor class myosin XI is known to function in rapid bulk flow of the cytoplasm (cytoplasmic streaming) and in organellar movements. Recent studies unveiled a wide range of physiological functions of myosin XI motors, from intracellular motility to organ movements. Arabidopsis thaliana has 13 members of myosin XI class. In vegetative organs, myosins XIk, XI1, and XI2 primarily contribute to dynamics and spatial configurations of endoplasmic reticulum that develops a tubular network in the cell periphery and thick strand-like structures in the inner cell regions. Myosin XI-i forms a nucleocytoplasmic linker and is responsible for nuclear movement and shape. In addition to these intracellular functions, myosin XIf together with myosin XIk is involved in the fundamental nature of plants; the actin-myosin XI cytoskeleton regulates organ straightening to adjust plant posture. PMID:26432645

  14. Numerical simulation of MHD pulsatile flow of a biofluid in a channel

    NASA Astrophysics Data System (ADS)

    Ali, Kashif; Ahmad, Shahzad; Ashraf, Muhammad

    2015-08-01

    The purpose of this paper is to numerically study the interaction of an external magnetic field with the flow of a biofluid through a Darcy-Forchhmeir porous channel, due to an oscillatory pressure gradient, in the presence of wall transpiration as well as chemical reaction considerations. We have noticed that if the Reynolds number of the wall transpiration flow is increased, the average (or maximum) velocity of the main flow direction is raised. Similar effect has also been observed for the rheological parameter and the Darcy parameter, whereas an opposite trend has been noted for both the Forchheimer quadratic drag parameter and the magnetic parameter. Further, an increase in the Reynolds number results in straightening the concentration profile, thus making it an almost linear function of the dimensionless spatial variable.

  15. Dental Arch Wire

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Straightening teeth is an arduous process requiring months, often years, of applying corrective pressure by means of arch wires-better known as brace-which may have to be changed several times in the course of treatment. A new method has been developed by Dr. George Andreasen, orthodontist and dental scientist at the University of Iowa. The key is a new type of arch wire material, called Nitinol, with exceptional elasticity which helps reduce the required number of brace changes. An alloy of nickel and titanium, Nitinol was originally developed for aerospace applications by the Naval Ordnance Laboratory, now the Naval Surface Weapons Laboratory, White Oaks, Maryland. NASA subsequently conducted additional research on the properties of Nitinol and on procedures for processing the metal.

  16. Translational control of a graphically simulated robot arm by kinematic rate equations that overcome elbow joint singularity

    NASA Technical Reports Server (NTRS)

    Barker, L. K.; Houck, J. A.; Carzoo, S. W.

    1984-01-01

    An operator commands a robot hand to move in a certain direction relative to its own axis system by specifying a velocity in that direction. This velocity command is then resolved into individual joint rotational velocities in the robot arm to effect the motion. However, the usual resolved-rate equations become singular when the robot arm is straightened. To overcome this elbow joint singularity, equations were developed which allow continued translational control of the robot hand even though the robot arm is (or is nearly) fully extended. A feature of the equations near full arm extension is that an operator simply extends and retracts the robot arm to reverse the direction of the elbow bend (difficult maneuver for the usual resolved-rate equations). Results show successful movement of a graphically simulated robot arm.

  17. Weld bead reinforcement removal: A method of improving the strength and ductility of peaked welds in 2219-T87 aluminum alloy plate

    NASA Technical Reports Server (NTRS)

    Lovoy, C. V.

    1979-01-01

    The results of a study to determine the degree to which the ductility and tensile properties of peaked welds could be enhanced by removing the reinforcing bead and fairing the weld nugget into the adjacent parent metal are presented. The study employed 2219-T87 aluminum alloy plate, tungsten inert gas (TIG) welding, and 2319 filler wire. The study concluded that significant improvements in peak weld, ultimate strength, and ductility can be obtained through removal and fairing of the weld reinforcing bead. The specimens so treated and tested in this program exhibited ultimate strength improvements of 2 to 3 percent for peak angles of 5.8 to 10 degrees and 10 to 22 percent for welds with peak angles of 11.7 to 16.9 degrees. It was also determined that removal of the weld bead enhanced the ability of peaked welds to straighten when exposed to cyclic loading at stress levels above the yield strength.

  18. The wire anchor loop traction (WALT) maneuver.

    PubMed

    Effendi, Khaled; Sacho, Raphael Hillel; Belzile, François; Marotta, Thomas R

    2016-02-01

    Crossing the neck of large complex intracranial aneurysms for the purposes of stent deployment can be challenging using standard over the wire techniques. We describe a novel yet simple technique for straightening out the loop formed within a large intracranial aneurysm, which is often required in order to cross the aneurysm neck into the distal branch. Both the microcatheter and microwire are initially introduced into the distal vasculature, followed by withdrawal of the microwire to a point parallel to the distal exiting branch. The microcatheter and microwire are then gently withdrawn and a series of maneuvers to gradually reduce the loop is performed, obviating the need for distal purchase in the form of a stent, balloon, or coil, which have previously been described to maintain distal purchase. PMID:25634903

  19. On load paths and load bearing topology from finite element analysis

    NASA Astrophysics Data System (ADS)

    Kelly, D.; Reidsema, C.; Lee, M.

    2010-06-01

    Load paths can be mapped from vector plots of 'pointing stress vectors'. They define a path along which a component of load remains constant as it traverses the solution domain. In this paper the theory for the paths is first defined. Properties of the plots that enable a designer to interpret the structural behavior from the contours are then identified. Because stress is a second order tensor defined on an orthogonal set of axes, the vector plots define separate paths for load transfer in each direction of the set of axes. An algorithm is therefore presented that combines the vectors to define a topology to carry the loads. The algorithm is shown to straighten the paths reducing bending moments and removing stress concentration. Application to a bolted joint, a racing car body and a yacht hull demonstrate the usefulness of the plots.

  20. Changing Pathology of the Thoracic Aorta From Acute to Chronic Dissection: Literature Review and Insights.

    PubMed

    Peterss, Sven; Mansour, Ahmed M; Ross, Julia A; Vaitkeviciute, Irena; Charilaou, Paris; Dumfarth, Julia; Fang, Hai; Ziganshin, Bulat A; Rizzo, John A; Adeniran, Adebowale J; Elefteriades, John A

    2016-09-01

    We review current knowledge regarding the natural transition of aortic dissection from acute to chronic stages. As this is not well understood, we also bring to bear new data from our institution. Type A dissection rarely transitions naturally into the chronic state; consequently, information is limited. Type B dissections are routinely treated medically and indeed undergo substantial changes during their temporal course. General patterns include: 1) the aorta dilates and, absent surgical intervention, aortic enlargement may cause mortality; 2) continued false lumen patency, particularly with an only partially thrombosed false lumen, increases aortic growth, whereas calcium-channel blockers affect aortic dilation favorably; 3) aortic dilation manifests a temporal dynamic, with early rapid growth and deceleration during transition; 4) the intimal flap dynamically changes over time via thickening, straightening, and loss of mobility; and 5) temporal remodeling, on the cellular level, initially shows a high grade of wall destruction; subsequently, significant fibrosis ensues. PMID:27585511

  1. Adaptive correction of the focused beam in conditions with strong fluctuations of intensity

    NASA Astrophysics Data System (ADS)

    Lukin, Vladimir P.; Fortes, Boris V.

    2000-07-01

    The adaptive correction was frequently treated as straightening of wavefront, if deal with receiving of the deformed wave. For adaptive focusing of beams the correction was considered as predistortion of wavefront. However with infringement of a condition smoothness of wavefront, the situation varies. It is known, that dislocations of wavefront conterminous to points where instant meaning of intensity equal to zero, arise with distances approximately equal diffraction length. With presence of such points the wavefront of a reference wave cannot be determined as a smooth one-coherent surface, therefore efficiency of adaptive systems with flexible mirrors begins to be reduced. At the same time, the numerical experiment with model of a compound phase corrector has shown, that its efficiency practically does not change with transition in area of strong fluctuations of intensity. We have found out, that the efficiency of adaptive system with a compound corrector does not vary with transition from area weak fluctuations of intensity in area strong fluctuations.

  2. Evaluation of microfilaricidal effects in the cornea from topically applied drugs in ocular onchocerciasis: Trials with levamisole and mebendazole.

    PubMed Central

    Jones, B R; Anderson, J; Fuglsang, H

    1978-01-01

    Increasing concentrations of levamisole and of mebendazole were applied to 1 eye in groups of 4 patients with ocular onchocerciasis in northern Cameroon. No effect resulted from up to 3.0% mebendazole suspensions, but 3.0% levamisole solutions rapidly caused entry of microfilariae, straightening out and subsequent opacification of previously curled-up living microfilariae, the rapid formation of typical limbal globular infiltrates, and the subsequent formation of fluffy opacities around the microfilariae. These changes are typical of all other drugs so far studied that have a microfilaricidal action on O. volvulus--diethlycarbamizine citrate (DEC), suramin, and metrifonate. The efficacy of 3.0% levamisole approximated to that of 0.03% DEC. This is in keeping with published observations on the filaricidal activity of these 2 compounds. It is suggested that this system of drug testing should be considered for systematic use in the search for more effective and safer drugs for onchocerciasis. Images PMID:678495

  3. On the tear resistance of skin

    PubMed Central

    Yang, Wen; Sherman, Vincent R.; Gludovatz, Bernd; Schaible, Eric; Stewart, Polite; Ritchie, Robert O.; Meyers, Marc A.

    2015-01-01

    Tear resistance is of vital importance in the various functions of skin, especially protection from predatorial attack. Here, we mechanistically quantify the extreme tear resistance of skin and identify the underlying structural features, which lead to its sophisticated failure mechanisms. We explain why it is virtually impossible to propagate a tear in rabbit skin, chosen as a model material for the dermis of vertebrates. We express the deformation in terms of four mechanisms of collagen fibril activity in skin under tensile loading that virtually eliminate the possibility of tearing in pre-notched samples: fibril straightening, fibril reorientation towards the tensile direction, elastic stretching and interfibrillar sliding, all of which contribute to the redistribution of the stresses at the notch tip. PMID:25812485

  4. Thoracic endovascular aortic repair of a severely angulated aorta using a double-wire technique

    PubMed Central

    Kawatani, Yohei; Nakamura, Yoshitsugu; Hayashi, Yujiro; Taneichi, Tetsuyoshi; Ito, Yujiro; Kurobe, Hirotsugu; Suda, Yuji; Hori, Takaki

    2016-01-01

    When endovascular treatment is performed, angulation of the access route for a device can make the operative procedure difficult. We encountered a case in which we successfully completed thoracic endovascular aortic repair (TEVAR) in a patient with severely angulated aorta by applying ‘double-wire technique’. The patient was an 80-year-old woman. An aneurysm with a 71-mm diameter was observed in the descending aorta. We performed TEVAR. Device delivery could not be achieved by a conventional procedure using one guide wire since the peripheral aorta was severely angulated. Therefore, in addition to a guide wire for main body, a stiff wire and a stiff sheath were introduced to straighten the angulation. The device was successfully introduced and TEVAR was completed. We used the Relay Plus® that facilitates tracking through the angulation. The device has a dual structure consisting of a hard sheath and a flexible sheath. We performed TEVAR successfully. PMID:27421301

  5. On the tear resistance of skin

    DOE PAGESBeta

    Yang, Wen; Sherman, Vincent R.; Gludovatz, Bernd; Schaible, Eric; Stewart, Polite; Ritchie, Robert O.; Meyers, Marc A.

    2015-03-27

    Tear resistance is vitally important for the various functions of skin, especially protection from predatorial attack. Here, we mechanistically quantify the extreme tear resistance of skin and identify the underlying structural features, which lead to its sophisticated failure mechanisms. Here we explain why it is virtually impossible to propagate a tear in rabbit skin, chosen as a model material for the dermis of vertebrates. Finally, we express the deformation in terms of four mechanisms of collagen fibril activity in skin under tensile loading that virtually eliminate the possibility of tearing in pre-notched samples: fibril straightening, fibril reorientation towards the tensilemore » direction, elastic stretching and interfibrillar sliding, all of which contribute to the redistribution of the stresses at the notch tip.« less

  6. A method of calibrating wind velocity sensors with a modified gas flow calibrator

    NASA Technical Reports Server (NTRS)

    Stump, H. P.

    1978-01-01

    A procedure was described for calibrating air velocity sensors in the exhaust flow of a gas flow calibrator. The average velocity in the test section located at the calibrator exhaust was verified from the mass flow rate accurately measured by the calibrator's precision sonic nozzles. Air at elevated pressures flowed through a series of screens, diameter changes, and flow straighteners, resulting in a smooth flow through the open test section. The modified system generated air velocities of 2 to 90 meters per second with an uncertainty of about two percent for speeds below 15 meters per second and four percent for the higher speeds. Wind tunnel data correlated well with that taken in the flow calibrator.

  7. Improvement of the Chairs in Classrooms for Better Sitting Posture of Children

    NASA Astrophysics Data System (ADS)

    Ishihara, Keiko; Dake, Kazuo; Ishihara, Shigekazu

    2010-10-01

    We sought to improve the sitting postures of children studying in the classrooms of a primary school. We made the seat of a standard chair lower and attached a cushion designed by one of the authors. The cushion is cut at a 25° downward angle toward the legs to allow the users to support their weight with their feet and alleviate pressure on the underside of the thighs. We also lowered the desktop to below the height of children's elbows. Eighty-three children were given the new chairs and desks, and they were observed over 7 months. Around 10% of them voluntarily maintained good sitting postures; others straightened their postures when the teachers reminded them to do so.

  8. The role of nodal and internodal responses in gravitropism and autotropism in Galium aparine L

    NASA Technical Reports Server (NTRS)

    Heathcote, D. G.; Brown, A. H. (Principal Investigator)

    1987-01-01

    This time course and location of gravitropically induced curvatures in stems of goosegrass (Gallium aparine L.), a member of the Rubiaceae, have been investigated. In the early stages of the response (0-5 h), curvature develops throughout the growing region, and is followed by an autotropic straightening which affects the internodes only, leading to the production of essentially straight internodes some 15 h after the onset of gravistimulation. Curvatures developing in the nodal regions, however, continue to increase over this period, and are not subject to reversal by autotropism. The nodal curvatures are not entirely dependent on the presence of any other part of the plant, since marked curvatures can be induced in isolated nodal segments. This pattern of response leads ultimately to correction of the growth direction of the plant by means of curvature responses confined exclusively to the nodes, despite the initial participation of both nodes and internodes in the gravitropic reaction.

  9. Cerebral arteriopathy associated with Arg179His ACTA2 mutation

    PubMed Central

    Amans, Matthew R; Stout, Charles; Fox, Christine; Narvid, Jared; Hetts, Steven W; Cooke, Daniel L; Higashida, Randall T; Dowd, Christopher F; McSwain, Hugh; Halbach, Van V

    2013-01-01

    ACTA2 mutations have recently been shown to cause a multisystem smooth muscle dysfunction syndrome that may result in pediatric stroke. We report a case of ACTA2 mutation in a 3-year-old girl presenting with acute ischemic stroke and provide high resolution imaging of the cerebral arteries demonstrating novel findings of multiple tiny aneurysms (particularly in the posterior circulation), as well as the more characteristic imaging phenotype of straightened and narrowed proximal intracranial vessels, dilated cervical vessels and occlusion of the M1 MCA segment without lenticulostriate collateral formation. This newly identified disease should be added to the differential diagnosis of pediatric stroke and cerebral vasculopathy. Neuroradiologists, interventionalists, surgeons and neurologists should become familiar with this rare disease and its clinical sequelae. PMID:24293535

  10. Characterizing a large shear-zone with seismic and magnetotelluric methods: The case of the Dead Sea Transform

    USGS Publications Warehouse

    Maercklin, N.; Bedrosian, P.A.; Haberland, C.; Ritter, O.; Ryberg, T.; Weber, M.; Weckmann, U.

    2005-01-01

    Seismic tomography, imaging of seismic scatterers, and magnetotelluric soundings reveal a sharp lithologic contrast along a ???10 km long segment of the Arava Fault (AF), a prominent fault of the southern Dead Sea Transform (DST) in the Middle East. Low seismic velocities and resistivities occur on its western side and higher values east of it, and the boundary between the two units coincides partly with a seismic scattering image. At 1-4 km depth the boundary is offset to the east of the AF surface trace, suggesting that at least two fault strands exist, and that slip occurred on multiple strands throughout the margin's history. A westward fault jump, possibly associated with straightening of a fault bend, explains both our observations and the narrow fault zone observed by others. Copyright 2005 by the American Geophysical Union.

  11. Stretching and ordering of amyloid fibrils at liquid interfaces

    NASA Astrophysics Data System (ADS)

    Del Gado, Emanuela; Schwenke, Konrad; Jordens, Sophia; Usov, Ivan; Mezzenga, Raffaele; Georgetown University Team; ETH Zurich Team

    We investigate the formation of nematic domains, which might be precursor of plaque formation, in the adsorption of amyloid fibrils at liquid interfaces. Combining experiments and computer simulations we analyse spatial correlations in the nematic order and in apparent persistence length. Non-equilibrium numerical simulations provide new insight into the coupling between those quantities. The emerging scenario is that the out-of-equilibrium adsorption favors the formation of spatial heterogeneities due to the presence of local nematic order that tend to persist upon increasing the surface coverage. Such structural heterogeneities are directly coupled to the apparent straightening of the brils and might affect the density and the mechanical properties of the final self-assembled material.

  12. Withdrawing method of the stiffening tube incidentally inserted into the descending colon.

    PubMed

    Fukuda, Shinsaku; Mikami, Tatsuya; Shimoyama, Tadashi; Hanabata, Norihiro; Iwamura, Hideki; Munakata, Akihiro

    2005-09-14

    We experienced a very rare complication of colonoscopy, a migration of stiffening tube into the colorectum. We herein introduce a withdrawing method of migrating stiffening tube incidentally inserted into the colorectum. A 65-year-old Japanese woman underwent colonoscopy because of abdominal discomfort. We used stiffening tube to insert the scope to the proximal colon because of her redundant sigmoid colon. When withdrawing the scope, we realized that the tube was fully inside the colorectum. We could not remove the tube instantly, and it reached the splenic flexure, finally. We reinserted the scope through the migrating tube, straightened the scope, and withdrew it holding a slight angle of the scope over the proximal end of the tube. Then, we could safely remove the tube along with the scope through the anus. PMID:16149153

  13. NASA Benefits Earth

    NASA Technical Reports Server (NTRS)

    Robinson, Julie A.

    2009-01-01

    This slide presentation reviews several ways in which NASA research has benefited Earth and made life on Earth better. These innovations include: solar panels, recycled pavement, thermometer pill, invisible braces for straightening teeth, LASIK, aerodynamic helmets and tires for bicycles, cataract detection, technology that was used to remove Anthrax spores from mail handling facilities, study of atomic oxygen erosion of materials has informed the restoration of artwork, macroencapsulation (a potential mechanism to deliver anti cancer drugs to specific sites), and research on a salmonella vaccine. With research on the International Space Station just beginning, there will be opportunities for entrepreneurs and other government agencies to access space for their research and development. As well as NASA continuing its own research on human health and technology development.

  14. Endoscopes and robots for tight surgical spaces: use of precurved elastic elements to enhance curvature

    NASA Astrophysics Data System (ADS)

    Remirez, Andria A.; Webster, Robert J.

    2016-03-01

    Many applications in medicine require flexible surgical manipulators and endoscopes capable of reaching tight curvatures. The maximum curvature these devices can achieve is often restricted either by a strain limit, or by a maximum actuation force that the device's components can tolerate without risking mechanical failure. In this paper we propose the use of precurvature to "bias" the workspace of the device in one direction. Combined with axial shaft rotation, biasing increases the size of the device's workspace, enabling it to reach tighter curvatures than a comparable device without biasing can achieve, while still being able to fully straighten. To illustrate this effect, we describe several example prototype devices which use flexible nitinol strips that can be pushed and pulled to generate bending. We provide a statics model that relates the manipulator curvature to actuation force, and validate it experimentally.

  15. Van der Waals forces in the perfluorinated metal-organic framework zinc 1,2-bis(4-pyridyl)ethane tetrafluoroterephthalate.

    PubMed

    Chang, Bor Kae; Bristowe, Nicholas C; Bristowe, Paul D; Cheetham, Anthony K

    2012-05-21

    Traditional density functional theory (DFT) and dispersion-corrected DFT calculations are performed to investigate the metal-organic framework zinc 1,2-bis(4-pyridyl)ethane tetrafluoroterephthalate (Znbpetpa). Without dispersion correction, straightening of the zigzag C-O-Zn chain connecting the secondary building units across the diagonal of the unit cell is observed, accompanied by a large anisotropic expansion of the structure along one cell parameter. The results show that van der Waals dispersion forces and specifically Zn-C equatorial interactions and the resulting effects on the zigzag chain play an important role in maintaining key structural features which match with experimental observations. It is suggested that the pore volume of the framework could be controlled by substituting the Zn metal centre with another transition element of different polarizability, while maintaining functional linkers. PMID:22482115

  16. [Polychromatic method of simultaneously demonstrating all the structural components of a peripheral nerve].

    PubMed

    Dolishniĭ, N V; Mel'man, E P

    1978-02-01

    To study neuro-vessel relations in the nerve conductive system, a combined method revealing myelinated and non-myelinated nerve fibers and blood vessels was suggested. The method includes the following stages of material treatment: injection of the nerve blood vessels with chloroform emulsion of Paris blue (5--10 g of the dye in 100 g of the solvant); the straightened nerves about 5 mm long are fixed in 12% neutral formalin; etching in the solution of chromium solts; embedding in paraffin and preparation of thin sections (3--5 mcm); staining after Masson's method applied for collagen fiber staining) in the author's modification and mounting in balsam. In the preparations, the axons of the nerve fibers are seen blue--purple, myelin sheaths--light red, connective tissue elements--violet and blood vessels are seen as dark blue rings. PMID:77154

  17. S-192 analysis: Conventional and special data processing techniques. [Michigan

    NASA Technical Reports Server (NTRS)

    Nalepka, R. F. (Principal Investigator); Morganstern, J.; Cicone, R.; Sarno, J.; Lambeck, P.; Malila, W.

    1975-01-01

    The author has identified the following significant results. Multispectral scanner data gathered over test sites in southeast Michigan were analyzed. This analysis showed the data to be somewhat deficient especially in terms of the limited signal range in most SDOs and also in regard to SDO-SDO misregistration. Further analysis showed that the scan line straightening algorithm increased the misregistration of the data. Data were processed using the conic format. The effects of such misregistration on classification accuracy was analyzed via simulation and found to be significant. Results of employing conventional as well as special, unresolved object, processing techniques were disappointing due, at least in part, to the limited signal range and noise content of the data. Application of a second class of special processing techniques, signature extension techniques, yielded better results. Two of the more basic signature extension techniques seemed to be useful in spite of the difficulties.

  18. Cerebral arteriopathy associated with Arg179His ACTA2 mutation.

    PubMed

    Amans, Matthew R; Stout, Charles; Fox, Christine; Narvid, Jared; Hetts, Steven W; Cooke, Daniel L; Higashida, Randall T; Dowd, Christopher F; McSwain, Hugh; Halbach, Van V

    2013-01-01

    ACTA2 mutations have recently been shown to cause a multisystem smooth muscle dysfunction syndrome that may result in pediatric stroke. We report a case of ACTA2 mutation in a 3-year-old girl presenting with acute ischemic stroke and provide high resolution imaging of the cerebral arteries demonstrating novel findings of multiple tiny aneurysms (particularly in the posterior circulation), as well as the more characteristic imaging phenotype of straightened and narrowed proximal intracranial vessels, dilated cervical vessels and occlusion of the M1 MCA segment without lenticulostriate collateral formation. This newly identified disease should be added to the differential diagnosis of pediatric stroke and cerebral vasculopathy. Neuroradiologists, interventionalists, surgeons and neurologists should become familiar with this rare disease and its clinical sequelae. PMID:24293535

  19. Cerebral arteriopathy associated with Arg179His ACTA2 mutation.

    PubMed

    Amans, Matthew R; Stout, Charles; Fox, Christine; Narvid, Jared; Hetts, Steven W; Cooke, Daniel L; Higashida, Randall T; Dowd, Christopher F; McSwain, Hugh; Halbach, Van V

    2014-11-01

    ACTA2 mutations have recently been shown to cause a multisystem smooth muscle dysfunction syndrome that may result in pediatric stroke. We report a case of ACTA2 mutation in a 3-year-old girl presenting with acute ischemic stroke and provide high resolution imaging of the cerebral arteries demonstrating novel findings of multiple tiny aneurysms (particularly in the posterior circulation), as well as the more characteristic imaging phenotype of straightened and narrowed proximal intracranial vessels, dilated cervical vessels and occlusion of the M1 MCA segment without lenticulostriate collateral formation. This newly identified disease should be added to the differential diagnosis of pediatric stroke and cerebral vasculopathy. Neuroradiologists, interventionalists, surgeons and neurologists should become familiar with this rare disease and its clinical sequelae. PMID:24353327

  20. Bending strain tolerance of MgB2 superconducting wires

    NASA Astrophysics Data System (ADS)

    Kováč, P.; Hušek, I.; Melišek, T.; Kulich, M.; Kopera, L.

    2016-04-01

    This work describes the strain tolerance of MgB2 superconductors subjected to variable bending stresses. Bending of MgB2 wire was done at room temperature in different modes: (i) direct bending of straight annealed samples to variable diameters and by (ii) indirect bending by straightening of bent and annealed samples. I c-bending strain characteristics of samples made by in situ PIT and by the internal magnesium diffusion (IMD) process were measured at 4.2 K. The results show a good agreement between the direct and indirect bending mode, which allows easier estimation of limits important for the winding process of MgB2 superconductors with brittle filaments. A comparison of MgB2 wires made by in situ PIT and IMD processes showed improved strain tolerance for IMD due to better grain connectivity the low annealing temperature, which does not appear to reduce the mechanical strength of sheath material.

  1. On the tear resistance of skin.

    PubMed

    Yang, Wen; Sherman, Vincent R; Gludovatz, Bernd; Schaible, Eric; Stewart, Polite; Ritchie, Robert O; Meyers, Marc A

    2015-01-01

    Tear resistance is of vital importance in the various functions of skin, especially protection from predatorial attack. Here, we mechanistically quantify the extreme tear resistance of skin and identify the underlying structural features, which lead to its sophisticated failure mechanisms. We explain why it is virtually impossible to propagate a tear in rabbit skin, chosen as a model material for the dermis of vertebrates. We express the deformation in terms of four mechanisms of collagen fibril activity in skin under tensile loading that virtually eliminate the possibility of tearing in pre-notched samples: fibril straightening, fibril reorientation towards the tensile direction, elastic stretching and interfibrillar sliding, all of which contribute to the redistribution of the stresses at the notch tip. PMID:25812485

  2. Cy3-DNA Stacking Interactions Strongly Depend on the Identity of the Terminal Basepair

    PubMed Central

    Spiriti, Justin; Binder, Jennifer K.; Levitus, Marcia; van der Vaart, Arjan

    2011-01-01

    We characterized the effect of the first basepair on the conformational dynamics of the fluorescent dye Cy3 attached to the 5′ end of double-stranded DNA using Gaussian-mixture adaptive umbrella sampling simulations. In the simulations, the sampling of all five dihedral angles along the linker was enhanced, so that both stacked and unstacked states were sampled. The affinity of Cy3 for a T·A basepair (with the dye attached to T) was found to be significantly less than for the other basepairs. This was verified experimentally by measuring the activation energies for cis-trans isomerization of the dye. The simulation and experimental results indicate the existence of partially unstacked conformations amenable to photoisomerization. The simulations also showed that stacking of Cy3 straightens the DNA while stabilizing the first basepair. Our findings indicate that fluorescence is modulated by Cy3-DNA interactions in a sequence-dependent manner. PMID:21320450

  3. Black women's hair: the main scalp dermatoses and aesthetic practices in women of African ethnicity *

    PubMed Central

    Tanus, Aline; Oliveira, Camila Caberlon Cruz; Villarreal, Delky Johanna Villarreal; Sanchez, Fernando Andres Vargas; Dias, Maria Fernanda Reis Gavazzoni

    2015-01-01

    Afro-ethnic hair is different from Caucasian and Asian hair and has unique features. Ethnic hair is more prone to certain conditions or diseases. Such diseases are not only related to the fragile inner structure of the hair, but also to the cultural habits of hairstyles that often exert traction forces upon the pilosebaceous follicle. Women with African hair subject their hair to chemical treatments such as hair straightening and relaxing, and thus modify the structure of their hair shaft, making it more susceptible to damage. For this reason, hair complaints are common among black women and represent a diagnostic challenge to the dermatologist, requiring a thorough clinical examination of the hair and scalp, and a detailed medical history of the patient. The purpose of this review is to warn of the potential side effects and sequelae related to hairstyles and hair treatments used by black women, and to highlight the major diseases that affect this ethnicity. PMID:26375213

  4. On the tear resistance of skin

    SciTech Connect

    Yang, Wen; Sherman, Vincent R.; Gludovatz, Bernd; Schaible, Eric; Stewart, Polite; Ritchie, Robert O.; Meyers, Marc A.

    2015-03-27

    Tear resistance is vitally important for the various functions of skin, especially protection from predatorial attack. Here, we mechanistically quantify the extreme tear resistance of skin and identify the underlying structural features, which lead to its sophisticated failure mechanisms. Here we explain why it is virtually impossible to propagate a tear in rabbit skin, chosen as a model material for the dermis of vertebrates. Finally, we express the deformation in terms of four mechanisms of collagen fibril activity in skin under tensile loading that virtually eliminate the possibility of tearing in pre-notched samples: fibril straightening, fibril reorientation towards the tensile direction, elastic stretching and interfibrillar sliding, all of which contribute to the redistribution of the stresses at the notch tip.

  5. High septal osteotomy in rhinoplasty for the deviated nose.

    PubMed

    Jameson, John J; Perry, Adam D; Ritter, Edmond F

    2006-01-01

    When attempting to straighten a patient's healed, deviated bony nasal dorsum, deviation of the central structure (high dorsal septum and medial nasal bones) must be addressed following the completion of medial and lateral osteotomies. When hump resection is not performed, blunt fracture (digitally or with forceps) of the deviated central structure is not a reliable method of mobilization, often leading to postoperative nasal drift. An intranasal osteotomy technique to mobilize the central structure of the nose is described, called "high septal osteotomy." Review of 25 cases suggests high septal osteotomy, supplemented as needed by resection of overlapping septal elements, can be performed safely and efficaciously, permitting stable midline reduction of the nasal pyramid. The technique is not advocated when hump resection is performed, as it is unnecessary and could destabilize the dorsum. Even aggressive maneuvers to mobilize the bony dorsum may fail if not performed properly with meticulous attention to completion of all osteotomies. PMID:16374094

  6. Molecular Order of Arterial Collagen Using Circular Polarization Second-Harmonic Generation Imaging.

    PubMed

    Turcotte, Raphaël; Mattson, Jeffrey M; Wu, Juwell W; Zhang, Yanhang; Lin, Charles P

    2016-02-01

    Second-harmonic generation (SHG) originates from the interaction between upconverted fields from individual scatterers. This renders SHG microscopy highly sensitive to molecular distribution. Here, we aim to take advantage of the difference in SHG between aligned and partially aligned molecules to probe the degree of molecular order during biomechanical testing, independently of the absolute orientation of the scattering molecules. Toward this goal, we implemented a circular polarization SHG imaging approach and used it to quantify the intensity change associated with collagen fibers straightening in the arterial wall during mechanical stretching. We were able to observe the delayed alignment of collagen fibers during mechanical loading, thus demonstrating a simple method to characterize molecular distribution using intensity information alone. PMID:26806883

  7. Laser reshaping of nasal septum cartilage: clinical results for 40 patients

    NASA Astrophysics Data System (ADS)

    Sobol, Emil N.; Sviridov, Alexander P.; Bagratashvili, Victor N.; Omelchenko, Alexander I.; Ovchinnikov, Yuriy M.; Shekhter, Anatoliy B.; Svistushkin, Valeriy M.; Shinaev, Alexander N.

    2000-05-01

    Clinical results on sparing laser reshaping of nasal septum cartilage are reported for the first time. Forty patients have been treated with holmium laser to correct a deformed cartilage. The laser reshaping is a bloodless, painless procedure which takes few minutes to straighten nasal septum. The stability of the new shape and possible side effects have been examined during twelve months. The headache and other negative symptoms have disappeared, as a result of laser treatment for the most of patients. Rhinoscopic examination show an excellent long-term reshaping effects for nasal septum of 23 patients, and, also, good results for other 12 patients. For 5 patients only a little effect takes place. Our rhinomanometric examinations demonstrate a pronounced improvement of the breathing for 35 patients. No visible undesirable side effects were observed for all patients underwent to laser reshaping procedure.

  8. Aluminum alloy 6013 sheet for new U.S. Navy aircraft

    NASA Astrophysics Data System (ADS)

    Kaneko, R. S.; Bakow, L.; Lee, E. W.

    1990-05-01

    The recently developed aluminum alloy 6013-T6 has been selected for the fuselage skin and other applications on the U.S. Navy's P-7A airplane, in place of the traditional 2024-T3 clad sheet. Alloy 6013-T6 is naturally corrosion resistant, like the well-established alloy 6061, and hence is used unclad. Its fatigue strength, fatigue crack growth and fracture toughness compare favorably with 2024-T3. Replacement of alloy 2024 with alloy 6013 also reduces manufacturing costs for formed parts, because 6013 is readily formed in the T4 temper, then simply aged to T6, thus avoiding the costly heat treatments and straightening required for alloy 2024.

  9. Algebro-geometric solutions to the modified Sawada-Kotera hierarchy

    NASA Astrophysics Data System (ADS)

    Wu, Lihua; He, Guoliang; Geng, Xianguo

    2012-12-01

    Based on solving the Lenard recursion equation and the zero-curvature equation, we derive the modified Sawada-Kotera (SK) hierarchy associated with a 3 × 3 matrix spectral problem. Resorting to the characteristic polynomial of Lax matrix for the modified SK hierarchy, we introduce a trigonal curve K_{m-1} and present the corresponding Baker-Akhiezer function and meromorphic function on it. The Abel map is introduced to straighten out the modified SK flows. With the aid of the property of the Baker-Akhiezer function and the meromorphic function and their asymptotic expansions, we arrive at their explicit Riemann theta function representations. Algebro-geometric solutions of the entire modified SK hierarchy are obtained by using asymptotic expansion of the meromorphic function and its Riemann theta function representation. As an application, we give two simple examples.

  10. Quasi-periodic Solutions of the Kaup-Kupershmidt Hierarchy

    NASA Astrophysics Data System (ADS)

    Geng, Xianguo; Wu, Lihua; He, Guoliang

    2013-08-01

    Based on solving the Lenard recursion equations and the zero-curvature equation, we derive the Kaup-Kupershmidt hierarchy associated with a 3×3 matrix spectral problem. Resorting to the characteristic polynomial of the Lax matrix for the Kaup-Kupershmidt hierarchy, we introduce a trigonal curve {K}_{m-1} and present the corresponding Baker-Akhiezer function and meromorphic function on it. The Abel map is introduced to straighten out the Kaup-Kupershmidt flows. With the aid of the properties of the Baker-Akhiezer function and the meromorphic function and their asymptotic expansions, we arrive at their explicit Riemann theta function representations. The Riemann-Jacobi inversion problem is achieved by comparing the asymptotic expansion of the Baker-Akhiezer function and its Riemann theta function representation, from which quasi-periodic solutions of the entire Kaup-Kupershmidt hierarchy are obtained in terms of the Riemann theta functions.