Sample records for scratch test analysis

  1. Induction of scratching behaviour in cats: efficacy of synthetic feline interdigital semiochemical.

    PubMed

    Cozzi, Alessandro; Lecuelle, Céline Lafont; Monneret, Philippe; Articlaux, Florence; Bougrat, Laurent; Mengoli, Manuel; Pageat, Patrick

    2013-10-01

    The aim of the study was to evaluate the effects of synthetic feline interdigital semiochemical (FIS) on the induction of scratching behaviour in cats during a standardised behavioural test. The trial was a randomised blinded study on a single group of subjects, following a crossover design. The scratching behaviour of 19 cats was evaluated during a standardised test in which cats were introduced to an area with one scratching post. Each cat acted as its own control (receiving, at random, FIS then placebo or vice versa). The test lasted for 5 mins, after which the cat was left alone in the test area. Duration, frequency of scratching and latency of first scratching behaviour were noted. Two independent observers analysed the videos. Thirty-eight tests were recorded with a different scratching post each time (two tests per cat). The scratching post with the semiochemical was more scratched in duration and frequency by the cats involved in the study (intention to treat analysis). The same conclusion was found using per-protocol analysis, which included only cats that scratched during the test. Regarding latency, no significant difference was found between treatment and placebo. The results seem of interest in explaining the role of a FIS in inducing scratching behaviour on a scratching post. The semiochemical approach can modify the choice of areas selected spontaneously by cats, and could be used either as a preventive measure for a cat arriving at home or to control or change an inappropriate scratching behaviour.

  2. Infrared spectroscopy, nano-mechanical properties, and scratch resistance of esthetic orthodontic coated archwires.

    PubMed

    da Silva, Dayanne Lopes; Santos, Emanuel; Camargo, Sérgio de Souza; Ruellas, Antônio Carlos de Oliveira

    2015-09-01

    To evaluate the material composition, mechanical properties (hardness and elastic modulus), and scratch resistance of the coating of four commercialized esthetic orthodontic archwires. The coating composition of esthetic archwires was assessed by Fourier-transform infrared spectroscopy (FTIR). Coating hardness and elastic modulus were analyzed with instrumented nano-indentation tests. Scratch resistance of coatings was evaluated by scratch test. Coating micromorphologic characteristics after scratch tests were observed in a scanning electron microscope. Statistical differences were investigated using analysis of variance and Tukey post hoc test. The FTIR results indicate that all analyzed coatings were markedly characterized by the benzene peak at about 1500 cm(-1). The coating hardness and elastic modulus average values ranged from 0.17 to 0.23 GPa and from 5.0 to 7.6 GPa, respectively. Scratch test showed a high coating elasticity after load removal with elastic recoveries >60%, but different failure features could be observed along the scratches. The coatings of esthetic archwires evaluated are probably a composite of polyester and polytetrafluoroethylene. Delamination, crack propagation, and debris generation could be observed along the coating scratches and could influence its durability in the oral environment.

  3. Standardization of a Volumetric Displacement Measurement for Two-Body Abrasion Scratch Test Data Analysis

    NASA Technical Reports Server (NTRS)

    Street, K. W. Jr.; Kobrick, R. L.; Klaus, D. M.

    2011-01-01

    A limitation has been identified in the existing test standards used for making controlled, two-body abrasion scratch measurements based solely on the width of the resultant score on the surface of the material. A new, more robust method is proposed for analyzing a surface scratch that takes into account the full three-dimensional profile of the displaced material. To accomplish this, a set of four volume- displacement metrics was systematically defined by normalizing the overall surface profile to denote statistically the area of relevance, termed the Zone of Interaction. From this baseline, depth of the trough and height of the plowed material are factored into the overall deformation assessment. Proof-of-concept data were collected and analyzed to demonstrate the performance of this proposed methodology. This technique takes advantage of advanced imaging capabilities that allow resolution of the scratched surface to be quantified in greater detail than was previously achievable. When reviewing existing data analysis techniques for conducting two-body abrasive scratch tests, it was found that the ASTM International Standard G 171 specified a generic metric based only on visually determined scratch width as a way to compare abraded materials. A limitation to this method was identified in that the scratch width is based on optical surface measurements, manually defined by approximating the boundaries, but does not consider the three-dimensional volume of material that was displaced. With large, potentially irregular deformations occurring on softer materials, it becomes unclear where to systematically determine the scratch width. Specifically, surface scratches on different samples may look the same from a top view, resulting in an identical scratch width measurement, but may vary in actual penetration depth and/or plowing deformation. Therefore, two different scratch profiles would be measured as having identical abrasion properties, although they differ significantly.

  4. Validation of Proposed Metrics for Two-Body Abrasion Scratch Test Analysis Standards

    NASA Technical Reports Server (NTRS)

    Kobrick, Ryan L.; Klaus, David M.; Street, Kenneth W., Jr.

    2011-01-01

    The objective of this work was to evaluate a set of standardized metrics proposed for characterizing a surface that has been scratched from a two-body abrasion test. This is achieved by defining a new abrasion region termed Zone of Interaction (ZOI). The ZOI describes the full surface profile of all peaks and valleys, rather than just measuring a scratch width as currently defined by the ASTM G 171 Standard. The ZOI has been found to be at least twice the size of a standard width measurement, in some cases considerably greater, indicating that at least half of the disturbed surface area would be neglected without this insight. The ZOI is used to calculate a more robust data set of volume measurements that can be used to computationally reconstruct a resultant profile for detailed analysis. Documenting additional changes to various surface roughness parameters also allows key material attributes of importance to ultimate design applications to be quantified, such as depth of penetration and final abraded surface roughness. Data are presented to show that different combinations of scratch tips and abraded materials can actually yield the same scratch width, but result in different volume displacement or removal measurements and therefore, the ZOI method is more discriminating than the ASTM method scratch width. Furthermore, by investigating the use of custom scratch tips for our specific needs, the usefulness of having an abrasion metric that can measure the displaced volume in this standardized manner, and not just by scratch width alone, is reinforced. This benefit is made apparent when a tip creates an intricate contour having multiple peaks and valleys within a single scratch. This work lays the foundation for updating scratch measurement standards to improve modeling and characterization of three-body abrasion test results.

  5. Electrical Arc Ignition Testing of Spacesuit Materials

    NASA Technical Reports Server (NTRS)

    Smith, Sarah; Gallus, Tim; Tapia, Susana; Ball, Elizabeth; Beeson, Harold

    2006-01-01

    A viewgraph presentation on electrical arc ignition testing of spacesuit materials is shown. The topics include: 1) Background; 2) Test Objectives; 3) Test Sample Materials; 4) Test Methods; 5) Scratch Test Objectives; 6) Cotton Scratch Test Video; 7) Scratch Test Results; 8) Entire Date Plot; 9) Closeup Data Plot; 10) Scratch Test Problems; 11) Poke Test Objectives; 12) Poke Test Results; 13) Poke Test Problems; 14) Wire-break Test Objectives; 15) Cotton Wire-Break Test Video; 16) High Speed Cotton Wire-break Test Video; 17) Typical Data Plot; 18) Closeup Data Plot; 19) Wire-break Test Results; 20) Wire-break Tests vs. Scratch Tests; 21) Urethane-coated Nylon; and 22) Moleskin.

  6. Screen Cage Ion Plating (SCIP) and scratch testing of polycrystalline aluminum oxide

    NASA Technical Reports Server (NTRS)

    Spalvins, Talivaldis; Sliney, Harold E.; Deadmore, Daniel L.

    1992-01-01

    A screen cage ion plating (SCIP) technique was developed to apply silver films on electrically nonconducting aluminum oxide. It is shown that SCIP has remarkable throwing power; surfaces to be coated need not be in direct line of sight with the evaporation source. Scratch tests, employing a diamond stylus with a 200 micro m radius tip, were performed on uncoated and on silver coated alumina. Subsequent surface analysis show that a significant amount of silver remains on the scratched surfaces, even in areas where high stylus load produced severe crack patterns in the ceramic. Friction coefficients were lowered during the scratch tests on the coated alumina indicating that this modification of the ion planting process should be useful for applying lubricating films of soft metals to electrical insulating materials. The very good throwing power of SCIP also strongly suggests general applicability of this process in other areas of technology, e.g., electronics, in addition to tribology.

  7. The effect of ion plated silver and sliding friction on tensile stress-induced cracking in aluminum oxide

    NASA Technical Reports Server (NTRS)

    Sliney, Harold E.; Spalvins, Talivaldis

    1991-01-01

    A Hertzian analysis of the effect of sliding friction on contact stresses in alumina is used to predict the critical load for crack generation. The results for uncoated alumina and alumina coated with ion plated silver are compared. Friction coefficient inputs to the analysis are determined experimentally with a scratch test instrument employing an 0.2 mm radius diamond stylus. A series of scratches were made at constant load increments on coated and uncoated flat alumina surfaces. Critical loads for cracking are detected by microscopic examination of cross sections of scratches made at various loads and friction coefficients. Acoustic emission (AE) and friction trends were also evaluated as experimental techniques for determining critical loads for cracking. Analytical predictions correlate well with micrographic evidence and with the lowest load at which AE is detected in multiple scratch tests. Friction/load trends are not good indicators of early crack formation. Lubrication with silver films reduced friction and thereby increased the critical load for crack initiation in agreement with analytical predictions.

  8. The effect of ion-plated silver and sliding friction on tensile stress-induced cracking in aluminum oxide

    NASA Technical Reports Server (NTRS)

    Sliney, Harold E.; Spalvins, Talivaldis

    1993-01-01

    A Hertzian analysis of the effect of sliding friction on contact stresses in alumina is used to predict the critical load for crack generation. The results for uncoated alumina and alumina coated with ion plated silver are compared. Friction coefficient inputs to the analysis are determined experimentally with a scratch test instrument employing an 0.2 mm radius diamond stylus. A series of scratches were made at constant load increments on coated and uncoated flat alumina surfaces. Critical loads for cracking are detected by microscopic examination of cross sections of scratches made at various loads and friction coefficients. Acoustic emission (AE) and friction trends were also evaluated as experimental techniques for determining critical loads for cracking. Analytical predictions correlate well with micrographic evidence and with the lowest load at which AE is detected in multiple scratch tests. Friction/load trends are not good indicators of early crack formation. Lubrication with silver films reduced friction and thereby increased the critical load for crack initiation in agreement with analytical predictions.

  9. Validation of Proposed Metrics for Two-Body Abrasion Scratch Test Analysis Standards

    NASA Technical Reports Server (NTRS)

    Street, Kenneth W., Jr.; Kobrick, Ryan L.; Klaus, David M.

    2013-01-01

    Abrasion of mechanical components and fabrics by soil on Earth is typically minimized by the effects of atmosphere and water. Potentially abrasive particles lose sharp and pointed geometrical features through erosion. In environments where such erosion does not exist, such as the vacuum of the Moon, particles retain sharp geometries associated with fracturing of their parent particles by micrometeorite impacts. The relationship between hardness of the abrasive and that of the material being abraded is well understood, such that the abrasive ability of a material can be estimated as a function of the ratio of the hardness of the two interacting materials. Knowing the abrasive nature of an environment (abrasive)/construction material is crucial to designing durable equipment for use in such surroundings. The objective of this work was to evaluate a set of standardized metrics proposed for characterizing a surface that has been scratched from a two-body abrasion test. This is achieved by defining a new abrasion region termed Zone of Interaction (ZOI). The ZOI describes the full surface profile of all peaks and valleys, rather than just measuring a scratch width. The ZOI has been found to be at least twice the size of a standard width measurement; in some cases, considerably greater, indicating that at least half of the disturbed surface area would be neglected without this insight. The ZOI is used to calculate a more robust data set of volume measurements that can be used to computationally reconstruct a resultant profile for de tailed analysis. Documenting additional changes to various surface roughness par ameters also allows key material attributes of importance to ultimate design applications to be quantified, such as depth of penetration and final abraded surface roughness. Further - more, by investigating the use of custom scratch tips for specific needs, the usefulness of having an abrasion metric that can measure the displaced volume in this standardized manner, and not just by scratch width alone, is reinforced. This benefit is made apparent when a tip creates an intricate contour having multiple peaks and valleys within a single scratch. The current innovation consists of a software- driven method of quantitatively evaluating a scratch profile. The profile consists of measuring the topographical features of a scratch along the length of the scratch instead of the width at one location. The digitized profile data is then fed into software code, which evaluates enough metrics of the scratch to reproduce the scratch from the evaluated metrics. There are three key differences between the current art and this innovation. First, scratch width does not quantify how far from the center of the scratch damage occurs (ZOI). Second, scratch width does not discern between material displacement and material removal from the scratch. Finally, several scratches may have the same width but different zones of interactions, different displacements, and different material removals. The current innovation allows quantitative assessment of all three.

  10. Prevalence and interest in the practice of scratch testing for contact urticaria: a survey of the American contact dermatitis society members.

    PubMed

    Orb, Quinn; Millsop, Jillian Wong; Harris, KaLynne; Powell, Douglas

    2014-01-01

    Contact urticaria (CU) is the development of a wheal and flare on the skin after topical exposure to a particular chemical or compound. It can be diagnosed through a variety of techniques. Many chemicals that cause a type IV allergy can also cause CU. The incidence of CU to these chemicals is unknown. The aim of this study was to evaluate the opinions of the American Contact Dermatitis Society members regarding CU and scratch testing. We distributed an electronic survey to the American Contact Dermatitis Society members regarding observed prevalence of CU, frequency of scratch testing in clinical practice, and interest in learning about scratch testing in diagnosing CU and other skin contact conditions. We distributed 508 surveys and received 133 responses. Seventeen percent reported that CU was extremely rare, 32% reported that CU was rare, and 38.9% reported that CU was infrequent. Alternatively, 10.7% believed that CU was common, and 1.5% believed that CU was extremely common. A minority, 19.1%, performed scratch testing on patients with suspected CU. Most respondents, 54.6%, were interested in learning about scratch testing. Additional education regarding scratch testing could increase comfort and use of scratch testing in clinical practice. Further studies are needed to evaluate the prevalence of CU in the general population and better guide the use of testing for dermatologic patients.

  11. CAT SCRATCH DISEASE: RESULTS OF COMPLEMENT-FIXATION AND SKIN TESTS

    DTIC Science & Technology

    Serologic and skin-testing data on a group of patients having cat scratch disease are presented to demonstrate a possible relationship to the psitt...indicate that the incidence of positive serologic reactions with the psitt-LGV group antigen is consistently higher in patients with cat scratch disease...patients, 2 of 5 did not respond with positive skin reactions when tested with cat scratch antigen, and at least 2 of the remaining 3 responded in a manner difficult to interpret.

  12. Scratching as a Fracture Process: From Butter to Steel

    NASA Astrophysics Data System (ADS)

    Akono, A.-T.; Reis, P. M.; Ulm, F.-J.

    2011-05-01

    We present results of a hybrid experimental and theoretical investigation of the fracture scaling in scratch tests and show that scratching is a fracture dominated process. Validated for paraffin wax, cement paste, Jurassic limestone and steel, we derive a model that provides a quantitative means to relate quantities measured in scratch tests to fracture properties of materials at multiple scales. The scalability of scratching for different probes and depths opens new venues towards miniaturization of our technique, to extract fracture properties of materials at even smaller length scales.

  13. Ultrasonic vibration double scratch morphology and scratching force of BK7 glass

    NASA Astrophysics Data System (ADS)

    Wang, Chu; Wang, Hongxiang; Liu, Junliang; Gao, Shi

    2018-03-01

    In this paper, the damage morphology and scratching force of BK7 glass components were analyzed by ultrasonic vibration double-scratch test. The results showed that there was surface damage caused by plastic flow and brittle fracture during the scratching process, and the scratching depth and the distance between the two scratches had effect on the propagation and overlapping of lateral cracks. When the scratching depth was small, the jagged scratch was produced on the surface, and accompanied by a small amount of tiny pieces of debris off. With the increase in scratching depth, the lateral cracks caused by scratching overlapped and expended to form a mesh sheet, and then fell off from the surface. When the scratching distance was small, the interaction of the cracks caused large slice of material to fall off. With the increase in scratching distance, the area between the two scratches was not easy to occur the overlapping of the lateral cracks. In addition, with the increase of the scratching depth, the scratching force showed a gradual increase trend, and the scratching force of the second scratch would increase with the scratching distance.

  14. A nanometric cushion for enhancing scratch and wear resistance of hard films

    PubMed Central

    Gotlib-Vainshtein, Katya; Girshevitz, Olga; Barlam, David

    2014-01-01

    Summary Scratch resistance and friction are core properties which define the tribological characteristics of materials. Attempts to optimize these quantities at solid surfaces are the subject of intense technological interest. The capability to modulate these surface properties while preserving both the bulk properties of the materials and a well-defined, constant chemical composition of the surface is particularly attractive. We report herein the use of a soft, flexible underlayer to control the scratch resistance of oxide surfaces. Titania films of several nm thickness are coated onto substrates of silicon, kapton, polycarbonate, and polydimethylsiloxane (PDMS). The scratch resistance measured by scanning force microscopy is found to be substrate dependent, diminishing in the order PDMS, kapton/polycarbonate, Si/SiO2. Furthermore, when PDMS is applied as an intermediate layer between a harder substrate and titania, marked improvement in the scratch resistance is achieved. This is shown by quantitative wear tests for silicon or kapton, by coating these substrates with PDMS which is subsequently capped by a titania layer, resulting in enhanced scratch/wear resistance. The physical basis of this effect is explored by means of Finite Element Analysis, and we suggest a model for friction reduction based on the "cushioning effect” of a soft intermediate layer. PMID:25161836

  15. Standardization of a Volumetric Displacement Measurement for Two-Body Abrasion Scratch Test Data Analysis

    NASA Technical Reports Server (NTRS)

    Kobrick, Ryan L.; Klaus, David M.; Street, Kenneth W., Jr.

    2010-01-01

    A limitation has been identified in the existing test standards used for making controlled, two-body abrasion scratch measurements based solely on the width of the resultant score on the surface of the material. A new, more robust method is proposed for analyzing a surface scratch that takes into account the full three-dimensional profile of the displaced material. To accomplish this, a set of four volume displacement metrics are systematically defined by normalizing the overall surface profile to statistically denote the area of relevance, termed the Zone of Interaction (ZOI). From this baseline, depth of the trough and height of the ploughed material are factored into the overall deformation assessment. Proof of concept data were collected and analyzed to demonstrate the performance of this proposed methodology. This technique takes advantage of advanced imaging capabilities that now allow resolution of the scratched surface to be quantified in greater detail than was previously achievable. A quantified understanding of fundamental particle-material interaction is critical to anticipating how well components can withstand prolonged use in highly abrasive environments, specifically for our intended applications on the surface of the Moon and other planets or asteroids, as well as in similarly demanding, harsh terrestrial settings

  16. Tribological Testing, Analysis and Characterization of D.C. Magnetron Sputtered Ti-Nb-N Thin Film Coatings on Stainless Steel

    NASA Astrophysics Data System (ADS)

    Joshi, Prathmesh

    To enhance the surface properties of stainless steel, the substrate was coated with a 1μm thick coating of Ti-Nb-N by reactive DC magnetron sputtering at different N2 flow rates, substrate biasing and Nb-Ti ratio. The characterization of the coated samples was performed by the following techniques: hardness by Knoop micro-hardness tester, phase analysis by X-ray Diffraction (XRD), compositional analysis by Energy Dispersive X-ray Spectroscopy (EDS) and adhesion by scratch test. The tribology testing was performed on linearly reciprocating ball-on-plate wear testing machine and wear depth and wear volume were evaluated by white light interferometer. The micro-hardness test yielded appreciable enhancement in the surface hardness with the highest value being 1450 HK. Presence of three prominent phases namely NbN, Nb2N3 and TiN resulted from the XRD analysis. EDS analysis revealed the presence of Ti, Nb and Nitrogen. Adhesion was evaluated on the basis of critical loads for cohesive (Lc1) and adhesive (Lc2) failures with values varying between 7-12 N and 16-25 N respectively, during scratch test for coatings on SS substrates.

  17. Validation of Scratching Severity as an Objective Assessment for Itch.

    PubMed

    Udkoff, Jeremy; Silverberg, Jonathan I

    2018-05-01

    There are currently no simple, standardized, objective assessments of itch for clinical trials and practice. We sought to validate and test the severity of scratching as an objective measure of itch (4-point ordinal scale ranging from 0 [not present] to 3 [very prominent] based on the observation of scratching lesions). We performed a prospective outpatient study using questionnaires and evaluations by a dermatologist in adults with atopic dermatitis (n = 261). Severity of scratching best correlated with patient-reported global atopic dermatitis severity (Kendall τ = 0.336, P < 0.0001), numeric rating scale of itch in the past 24 hours (τ = 0.266, P = 0.0010) and 3 days (τ = 0.296, P < 0.0001). Severity of scratching showed responsiveness over time. Patients experiencing improvement of scratching severity of 1 point or greater had significantly lower itch based on numeric rating scale in the past 3 days (Wilcoxon rank sum test, P = 0.0175), 5-D itch scale (P = 0.0146), and Patient-Oriented Eczema Measure scores (P = 0.0146). There was a significant decrease in scratching severity for patients experiencing itch improvement of 4 points or greater in the past 3 days on the numeric rating scale (Fisher exact test, P = 0.0026), Patient-Oriented Eczema Measure (P < 0.0001), and Dermatology Life Quality Index (P = 0.0285). Severity of scratching may be a useful endpoint in clinical trials and practice across the gamut of pruritic disorders. Future studies are needed to validate severity of scratching in other pruritic disease. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Development and validation of an automated system for detection and assessment of scratching in the rodent

    PubMed Central

    Marino, Marc; Huang, Polly; Malkmus, Shelle; Robertshaw, Erin; Mac, Elaine A.; Shatterman, Yuri; Yaksh, Tony L.

    2012-01-01

    Pruritus, the sensation of itch, which evokes reflex scratching behavior, has a diverse etiology. Because of its clinical significance, mechanisms of pruriception are an important topic. In the present work we describe and validate a paw motion detector (PMD) system. The system employs a small removable metal band placed on one hind paw that provides a signal indicative of paw movement through perturbation of an electromagnetic (EM) field. C57Bl/6 mice were fitted with a unilateral hind paw band and adapted to testing cylinders equipped with EM signal emission and detection. The following observations were made: 1) in mice, unilateral SQ injection of 48/80 into the dorsolateral aspect of the neck evoked periodic high frequency bursts of scratching at the injected site with the ipsilateral (banded) but not the contralateral (not banded) hind paw. 2) Cross correlation between PMD and human observer counts after SQ 48/80 using the specified computational algorithm revealed a highly significant correlation. 3) SQ histamine and 48/80 over a 1 hour interval produced dose dependent scratching, which diphenhydramine dose dependently reversed. Chloroquine scratching displayed an inverse u-shaped dose response curve, which was insensitive to diphenhydramine. 4) SQ 48/80 at intervals over 28 days showed no change in the scratching response within the same cohort of mice. 5) Power analysis showed 40% changes in scratching activity could be detected at the p<0.05 level with groups of 4 mice. These observations indicate that the system described can efficiently define the actions and pharmacology of pruritogenic agents. PMID:22971351

  19. Afferent control of central pattern generators: experimental analysis of scratching in the decerebrate cat.

    PubMed

    Baev, K V; Esipenko, V B; Shimansky, Y P

    1991-01-01

    Systematic quantitative analysis of changes in the spinal scratching generator motor activity evoked by tonic and phasic peripheral afferent signals during "fictitious" scratching was carried out in the cat. Correlations between the kinematics of hindlimb scratching movement, sensory inflow, and primary afferent depolarization were investigated. Reliable correlations between the parameters of generator motor activity during fictitious scratching were revealed: they depended on tonic peripheral afferent inflow. The functional role of these dependencies consists of providing stability for aiming the hindlimb to the itch site. It was shown that scratching generator reaction to a phasic sensory signal depended significantly on afferent input, signal intensity, and its arrival phase in the cycle of motor activity. Phase correction of "scratching" rhythm was performed by inhibition of the current stage of "scratching" cycle, the inhibition magnitude depending on the intensity of a sensory signal run along high threshold afferent fibers. The moments in the scratching cycle, in which the afferent signal caused no rearrangement in scratching generator activity, were discovered for all investigated afferent inputs. These moments corresponded to the transitions from one scratching cycle phase to another. Integral afferent activity was distributed unevenly in the cycle during real scratching. The main part of it was observed just in that scratching cycle part which included the above mentioned no rearrangement phase points. The data obtained allowed us to conclude that the scratching generator should be considered as a working program for the motor optimal control system containing the intrinsic model of the controlled object dynamics (e.g. hindlimb scratching movement dynamics), which produces an inner analog of peripheral flow. This inner flow interacts with peripheral afferent inflow just as one of the latter components. Centrally originated modulation of primary afferent depolarization is a result of affecting the depolarization generating system by this inner "sensory" activity. It is the model, with the aid of which the generator can work after deafferentation. The functional organization of a central pattern generator is considered.

  20. Wear behavior of austenite containing plate steels

    NASA Astrophysics Data System (ADS)

    Hensley, Christina E.

    As a follow up to Wolfram's Master of Science thesis, samples from the prior work were further investigated. Samples from four steel alloys were selected for investigation, namely AR400F, 9260, Hadfield, and 301 Stainless steels. AR400F is martensitic while the Hadfield and 301 stainless steels are austenitic. The 9260 exhibited a variety of hardness levels and retained austenite contents, achieved by heat treatments, including quench and tempering (Q&T) and quench and partitioning (Q&P). Samples worn by three wear tests, namely Dry Sand/Rubber Wheel (DSRW), impeller tumbler impact abrasion, and Bond abrasion, were examined by optical profilometry. The wear behaviors observed in topography maps were compared to the same in scanning electron microscopy micrographs and both were used to characterize the wear surfaces. Optical profilometry showed that the scratching abrasion present on the wear surface transitioned to gouging abrasion as impact conditions increased (i.e. from DSRW to impeller to Bond abrasion). Optical profilometry roughness measurements were also compared to sample hardness as well as normalized volume loss (NVL) results for each of the three wear tests. The steels displayed a relationship between roughness measurements and observed wear rates for all three categories of wear testing. Nanoindentation was used to investigate local hardness changes adjacent to the wear surface. DSRW samples generally did not exhibit significant work hardening. The austenitic materials exhibited significant hardening under the high impact conditions of the Bond abrasion wear test. Hardening in the Q&P materials was less pronounced. The Q&T microstructures also demonstrated some hardening. Scratch testing was performed on samples at three different loads, as a more systematic approach to determining the scratching abrasion behavior. Wear rates and scratch hardness were calculated from scratch testing results. Certain similarities between wear behavior in scratch testing and DSRW samples were observed. Different microstructures exhibited different scratching behaviors. Martensitic microstructures exhibited chipping and cracking, whereas Q&P microstructures exhibited limited or no chipping. The Q&P samples exhibited more deformation at greater loads and hardness levels than the martensitic microstructures. Austenitic microstructures exhibited significant deformation adjacent to the scratches.

  1. Assessment of Mudrock Brittleness with Micro-scratch Testing

    NASA Astrophysics Data System (ADS)

    Hernandez-Uribe, Luis Alberto; Aman, Michael; Espinoza, D. Nicolas

    2017-11-01

    Mechanical properties are essential for understanding natural and induced deformational behavior of geological formations. Brittleness characterizes energy dissipation rate and strain localization at failure. Brittleness has been investigated in hydrocarbon-bearing mudrocks in order to quantify the impact of hydraulic fracturing on the creation of complex fracture networks and surface area for reservoir drainage. Typical well logging correlations associate brittleness with carbonate content or dynamic elastic properties. However, an index of rock brittleness should involve actual rock failure and have a consistent method to quantify it. Here, we present a systematic method to quantify mudrock brittleness based on micro-mechanical measurements from the scratch test. Brittleness is formulated as the ratio of energy associated with brittle failure to the total energy required to perform a scratch. Soda lime glass and polycarbonate are used for comparison to identify failure in brittle and ductile mode and validate the developed method. Scratch testing results on mudrocks indicate that it is possible to use the recorded transverse force to estimate brittleness. Results show that tested samples rank as follows in increasing degree of brittleness: Woodford, Eagle Ford, Marcellus, Mancos, and Vaca Muerta. Eagle Ford samples show mixed ductile/brittle failure characteristics. There appears to be no definite correlation between micro-scratch brittleness and quartz or total carbonate content. Dolomite content shows a stronger correlation with brittleness than any other major mineral group. The scratch brittleness index correlates positively with increasing Young's modulus and decreasing Poisson's ratio, but shows deviations in rocks with distinct porosity and with stress-sensitive brittle/ductile behavior (Eagle Ford). The results of our study demonstrate that the micro-scratch test method can be used to investigate mudrock brittleness. The method is particularly useful for reservoir characterization methods that take advantage of drill cuttings or whenever large samples for triaxial testing or fracture mechanics testing cannot be recovered.

  2. Tribology behavior on scratch tests: Effects of yield strength

    DOE PAGES

    Feng, Biao

    2017-03-07

    In this paper, a three-dimensional (3D) scratch model is proposed to investigate the effects of yield strength of both coatings and substrates. With the help of combined Coulomb and plastic friction, the obtained results comprehensively interpret the experimental phenomena in most metals that with the growth of hardness after heat treatment the scratch friction coefficient (SFC) increases. This interpretation could not be done before. Scratch tests on the surface with or without the coating are discussed. Without the coating the SFC increases due to the decrease of the area with plastic slippage and/or the increase of friction stress during themore » increase of the yield strength in the material. With a softer substrate the friction stress decreases but the SFC increases, which is caused by the growth of the entire contact area and surface deformation. Conversely, with a stronger substrate the SFC decreases due to an intensified plastic slippage In conclusion, the obtained results pave a new way to understanding the effects of yield strength on scratch tests, interpret experimental phenomena, and should be helpful for an optimum design in experiments.« less

  3. Tribology behavior on scratch tests: Effects of yield strength

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

    Feng, Biao

    In this paper, a three-dimensional (3D) scratch model is proposed to investigate the effects of yield strength of both coatings and substrates. With the help of combined Coulomb and plastic friction, the obtained results comprehensively interpret the experimental phenomena in most metals that with the growth of hardness after heat treatment the scratch friction coefficient (SFC) increases. This interpretation could not be done before. Scratch tests on the surface with or without the coating are discussed. Without the coating the SFC increases due to the decrease of the area with plastic slippage and/or the increase of friction stress during themore » increase of the yield strength in the material. With a softer substrate the friction stress decreases but the SFC increases, which is caused by the growth of the entire contact area and surface deformation. Conversely, with a stronger substrate the SFC decreases due to an intensified plastic slippage In conclusion, the obtained results pave a new way to understanding the effects of yield strength on scratch tests, interpret experimental phenomena, and should be helpful for an optimum design in experiments.« less

  4. Use of non-standardised micro-destructive techniques in the characterization of traditional construction materials

    NASA Astrophysics Data System (ADS)

    Ioannou, Ioannis; Theodoridou, Magdalini; Modestou, Sevasti; Fournari, Revecca; Dagrain, Fabrice

    2013-04-01

    The characterization of material properties and the diagnosis of their state of weathering and conservation are three of the most important steps in the field of cultural heritage preservation. Several standardised experimental methods exist, especially for determining the material properties and their durability. However, they are limited in their application by the required size of test specimens and the controlled laboratory conditions needed to undertake the tests; this is especially true when the materials under study constitute immovable parts of heritage structures. The current use of other advanced methods of analysis, such as imaging techniques, in the aforementioned field of research offers invaluable results. However, these techniques may not always be accessible to the wider research community due to their complex nature and relatively high cost of application. This study presents innovative applications of two recently developed cutting techniques; the portable Drilling Resistance Measuring System (DRMS) and the scratch tool. Both methods are defined as micro-destructive, since they only destroy a very small portion of sample material. The general concept of both methods lies within the forces needed to cut a material by linear (scratch tool) or rotational (DRMS) cutting action; these forces are related to the mechanical properties of the material and the technological parameters applied on the tool. Therefore, for a given testing configuration, the only parameter influencing the forces applied is the strength of the material. These two techniques have been used alongside a series of standardised laboratory tests aiming at the correlation of various stone properties (density, porosity, dynamic elastic modulus and uniaxial compressive strength). The results prove the potential of both techniques in assessing the uniaxial compressive strength of stones. The scratch tool has also been used effectively to estimate the compressive strength of mud bricks. It therefore follows that both micro-destructive techniques may prove useful in the physico-mechanical characterization of materials which demand in-situ measurements or allow very limited sampling. Moreover, both techniques have been used, for the first time, to map the distribution of salts in building stone in the laboratory; micro-drilling was also applied in the same context in-situ. The results of the laboratory tests performed on limestone impregnated with sodium and magnesium sulfate confirm that both the scratch tool and the DRMS may successfully detect the location of the salt front, as they respond to pore clogging by salt crystals by providing increased scratching/drilling resistance values. Drilling and scratching of duplicate samples treated with a hydrophobic product show the sensitivity of both techniques as they clearly detect changes to the salt front location (i.e. cryptoflorescence) caused by surface treatments. Both techniques were also successful in highlighting the difference in the crystallisation location and pattern of magnesium sulphate and sodium chloride. In-situ application of the micro-drilling test demonstrated its potential for use in the assessment of masonry salt weathering; the results suggest that this technique may, in fact, be useful as a preventive measure against salt damage. Last but not least, both aforementioned novel micro-destructive techniques have been used to assess the effectiveness of commercially available consolidants. The results of the scratch tool have also been utilised to develop a tomography image of the samples under test. Scratching tomography may potentially be combined with in-situ micro-drilling tests to evaluate the effectiveness of consolidation treatments applied on monuments and historic buildings.

  5. Male DNA under female fingernails after scratching: transfer and persistence evaluation by RT-PCR analysis and Y-STR typing.

    PubMed

    Iuvaro, Alessandra; Bini, Carla; Dilloo, Silvia; Sarno, Stefania; Pelotti, Susi

    2018-04-17

    The collection of biological debris beneath fingernails can be useful in forensic casework when a struggle between the victim and the offender is suspected. In the present study, we set up a controlled scratching experiment in which female volunteers scratched the male volunteers' forearms, simulating a defensive action during an assault. A total of 160 fingernail samples were collected: 80 "control samples" before the scratching, 40 samples immediately after the scratching (t = 0 h), and 40 samples 5 h after the scratching (t = 5 h). The aim was to evaluate, using a real-time PCR approach and Y-STR profiling, the transfer and the persistence of male DNA under female fingernails after scratching. A significant reduction in DNA yield was observed between fingernail samples collected immediately and those collected 5 h after scratching, with a corresponding decrease in Y-STR profile quality. Overall, 38/40 (95%) of the fingernail samples collected immediately (t = 0 h) and 24/40 (60%) of those collected 5 h later (t = 5 h) were suitable for comparison and the scratched male volunteers could not be excluded as donors of the foreign DNA from 37 (92.5%) of the t = 0 h and from 10 (25%) of the t = 5 h profiles. The analysis of male DNA under female fingernails showed that Y-chromosome STR typing may provide extremely valuable genetic information of the male contributor(s), although 5 h after scratching the profile of the scratched male was lost in three-quarters of samples.

  6. Somatostatin receptor scintigraphy in patients with cat-scratch disease.

    PubMed

    Krause, R; Piswanger-Soelkner, C; Lipp, R W; Daxböck, F; Schnedl, W J; Hoier, S; Reisinger, E C

    2006-01-01

    Somatostatin receptor scintigraphy images various neoplastic, granulomatous, and auto-immune diseases. Cat-scratch disease in an infectious granulomatous disease usually affecting the lymphnodes. It is not known whether cat-scratch disease provides positive somatostatin receptor scintigrams. Twelve patients with lymphadenitis and suspected cat-scratch disease were investigated by immunofluorescence antibody testing and somatostatin receptor scintigraphy. Suppurated lymphnodes were extracted or drained and Bartonella henselae specific PCR was then performed. Eleven of 12 patients showed IgG antibodies against B. henselae. SRS showed positive scintigraphic results in 6 of 11 patients with CSD. B. henselae DNA was detected in tissue of lymphnodes from 4 of 5 patients with lymphnode extraction or lymphnode drainage. SRS demonstrated positive scintigrams in all patients with a positive PCR. In one patient with suspected CSD SRS was negative as well as antibody testing. Somatostatin receptor scintigraphy correlated with positive Bartonella henselae specific PCR tests and positive Bartonella henselae specific antibody tests in patients with CSD.

  7. Determining the direction of tooth grinding: an in vitro study.

    PubMed

    ten Berge, F; te Poel, J; Ranjitkar, S; Kaidonis, J A; Lobbezoo, F; Hughes, T E; Townsend, G C

    2012-08-01

    The analysis of microwear patterns, including scratch types and widths, has enabled reconstruction of the dietary habits and lifestyles of prehistoric and modern humans. The aim of this in vitro study was to determine whether an assessment of microwear features of experimental scratches placed on enamel, perpendicularly to the direction of grinding, could predict the grinding direction. Experimental scratches were placed using a scalpel blade on standardised wear facets that had been prepared by wearing opposing enamel surfaces in an electromechanical tooth wear machine. These control 'baseline' facets (with unworn experimental scratches) were subjected to 50 wear cycles, so that differential microwear could be observed on the leading and trailing edges of the 'final' facets. In Group 1 (n=28), the 'footprint' microwear patterns corresponding to the known grinding direction of specimens in the tooth wear machine were identified. Then, they were used to predict the direction of tooth grinding blindly in the same sample after a 2-week intermission period. To avoid overfitting the predictive model, its sensitivity was also cross-validated in a new sample (Group 2, n=14). A crescent-shaped characteristic observed in most experimental scratches matched the grinding direction on all occasions. The best predictor of the direction of grinding was a combined assessment of the leading edge microwear pattern and the crescent characteristic (82.1% in Group 1 and 92.9% in Group 2). In conclusion, a simple scratch test can determine the direction of tooth grinding with high reliability, although further improvement in sensitivity is desirable. © 2012 Blackwell Publishing Ltd.

  8. Surface deformation and friction characteristic of nano scratch at ductile-removal regime for optical glass BK7.

    PubMed

    Li, Chen; Zhang, Feihu; Ding, Ye; Liu, Lifei

    2016-08-20

    Nano scratch for optical glass BK7 based on the ductile-removal regime was carried out, and the influence rule of scratch parameters on surface deformation and friction characteristic was analyzed. Experimental results showed that, with increase of normal force, the deformation of burrs in the edge of the scratch was more obvious, and with increase of the scratch velocity, the deformation of micro-fracture and burrs in the edge of the scratch was more obvious similarly. The residual depth of the scratch was measured by atomic force microscope. The experimental results also showed that, with increase of normal force, the residual depth of the scratch increased linearly while the elastic recovery rate decreased. Furthermore, with increase of scratch velocity, the residual depth of the scratch decreased while the elastic recovery rate increased. The scratch process of the Berkovich indenter was divided into the cutting process of many large negative rake faces based on the improved cutting model, and the friction characteristic of the Berkovich indenter and the workpiece was analyzed. The analysis showed that the coefficient of friction increased and then tended to be stable with the increase of normal force. Meanwhile, the coefficient of friction decreased with the increase of scratch velocity, and the coefficients, k ln(v) and μ0, were introduced to improve the original formula of friction coefficient.

  9. Experimental investigation of the tip based micro/nano machining

    NASA Astrophysics Data System (ADS)

    Guo, Z.; Tian, Y.; Liu, X.; Wang, F.; Zhou, C.; Zhang, D.

    2017-12-01

    Based on the self-developed three dimensional micro/nano machining system, the effects of machining parameters and sample material on micro/nano machining are investigated. The micro/nano machining system is mainly composed of the probe system and micro/nano positioning stage. The former is applied to control the normal load and the latter is utilized to realize high precision motion in the xy plane. A sample examination method is firstly introduced to estimate whether the sample is placed horizontally. The machining parameters include scratching direction, speed, cycles, normal load and feed. According to the experimental results, the scratching depth is significantly affected by the normal load in all four defined scratching directions but is rarely influenced by the scratching speed. The increase of scratching cycle number can increase the scratching depth as well as smooth the groove wall. In addition, the scratching tests of silicon and copper attest that the harder material is easier to be removed. In the scratching with different feed amount, the machining results indicate that the machined depth increases as the feed reduces. Further, a cubic polynomial is used to fit the experimental results to predict the scratching depth. With the selected machining parameters of scratching direction d3/d4, scratching speed 5 μm/s and feed 0.06 μm, some more micro structures including stair, sinusoidal groove, Chinese character '田', 'TJU' and Chinese panda have been fabricated on the silicon substrate.

  10. 75 FR 54536 - Airworthiness Directives; Airbus Model A330-200 and -300 and A340-200 and -300 Series Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-08

    ... inspections for damage (such as a scratch, disbonding, or a tear) of the inner skin of the upper and lower... inspection to detect damage (such as a scratch, disbonding, or a tear), and a tap test and a thermographic..., do a special detailed inspection for discrepancies (scratches, debonding, tears, and indications of...

  11. Evaluation of anomalies observed on film from S-190A flight system calibration test

    NASA Technical Reports Server (NTRS)

    Bourque, P. F.; Perry, L.; Sauer, G. E.

    1975-01-01

    Due to a persistent problem of scratched film from testing of the Skylab S-190A system, a series of tests were designed to identify the cause of the film scratching. The procedures followed in this test for pretest handling and packaging of the film, the makeup of the rolls for processing, and the results of the processed film evaluation are reported.

  12. Adhesive and Cohesive Strength in FeB/Fe2B Systems

    NASA Astrophysics Data System (ADS)

    Meneses-Amador, A.; Blancas-Pérez, D.; Corpus-Mejía, R.; Rodríguez-Castro, G. A.; Martínez-Trinidad, J.; Jiménez-Tinoco, L. F.

    2018-05-01

    In this work, FeB/Fe2B systems were evaluated by the scratch test. The powder-pack boriding process was performed on the surface of AISI M2 steel. The mechanical parameters, such as yield stress and Young's modulus of the boride layer, were obtained by the instrumented indentation technique. Residual stresses produced on the boride layer were estimated by using the x-ray diffraction (XRD) technique. The scratch test was performed in order to evaluate the cohesive/adhesive strength of the FeB/Fe2B coating. In addition, a numerical evaluation of the scratch test on boride layers was performed by the finite element method. Maximum principal stresses were related to the failure mechanisms observed by the experimental scratch test. Shear stresses at the interfaces of the FeB/Fe2B/substrate system were also evaluated. Finally, the results obtained provide essential information about the effect of the layer thickness, the residual stresses, and the resilience modulus on the cohesive/adhesive strength in FeB/Fe2B systems.

  13. Scratching behaviour and its features: a questionnaire-based study in an Italian sample of domestic cats.

    PubMed

    Mengoli, Manuel; Mariti, Chiara; Cozzi, Alessandro; Cestarollo, Elisa; Lafont-Lecuelle, Céline; Pageat, Patrick; Gazzano, Angelo

    2013-10-01

    Scratching behaviour in cats is described as a normal expression of the feline ethogram, having different possible purposes related to visual and chemical communication. During behavioural consultations owners often mention scratching as an additional problem. This preliminary study aimed to understand the characteristics of this complex behaviour by examining the variables displayed by a sample of the Italian feline population using multiple correspondence analysis. One hundred and twenty-eight cats were screened by means of a questionnaire to identify features of their scratching behaviour. Our data showed the importance of both the presence/absence of a scratching post in the cat's living area and its relationship to marking. When a scratching post is present in a cat's living area, the cat appears to use it. Some aspects related to sex, neutering, age and environmental characteristics may modify the expression of scratching as a marking behaviour. Research has led to increased knowledge of this behaviour and may help veterinarians in describing to owners why it is important for cats to express scratching behaviour in their environment. Such information could help veterinarians and owners to recognise normal and problematic scratching behaviours.

  14. Relationship between thin-film bond strength as measured by a scratch test, and indentation hardness for bonding agents.

    PubMed

    Kusakabe, Shusuke; Rawls, H Ralph; Hotta, Masato

    2016-03-01

    To evaluate thin-film bond strength between a bonding agent and human dentin, using a scratch test, and the characteristics and accuracy of measurement. One-step bonding agents (BeautiBond; Bond Force; Adper Easy Bond; Clearfil tri-S Bond) and two-step bonding agents (Cleafil SE Bond; FL-Bond II) were investigated in this study. Flat dentin surfaces were prepared for extracted human molars. The dentin surfaces were ground and bonding agents were applied and light cured. The thin-film bond strength test of the specimens was evaluated by the critical load at which the coated bonding agent failed and dentin appeared. The scratch mark sections were then observed under a scanning electron microscope. Indentation hardness was evaluated by the variation in depth under an applied load of 10gf. Data were compared by one-way ANOVA with the Scheffé's post hoc multiple comparison test (p<0.05). In addition, thin-film bond strength and indentation hardness were analyzed using analysis of correlation and covariance. The thin-film bond strength of two-step bonding agents were found to be significantly higher than that of one-step bonding agents with small standard deviations. Scratch marks consistently showed adhesive failure in the vicinity of the bonding agent/dentin interface. The indentation hardness showed a trend that two-step bonding agents have greater hardness than one-step bonding agents. A moderately significant correlation (r(2)=0.31) was found between thin-film bond strength and indentation hardness. Thin-film bond strength test is a valid and reliable means of evaluating bond strength in the vicinity of the adhesive interface and is more accurate than other methods currently in use. Further, the thin-film bond strength is influenced by the hardness of the cued bonding agent. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  15. Nocebo Effects and Scratching Behaviour in Itch.

    PubMed

    Bartels, Danielle J P; van Laarhoven, Antoinette I M; van de Kerkhof, Peter C M; Evers, Andrea W M

    2018-06-01

    Nocebo effects, i.e. reduced treatment effects due to patients' negative expectations, play a role in itch. Recent studies have shown that nocebo effects can be induced experimentally in itch and even be reversed into the placebo effect. It is not known whether these effects generalize to itch-associated scratching behaviour. The aim of this study was to determine whether induction and reversion of nocebo effects in itch evoked by electrical and histamine stimuli generalized to scratching. Ninety-seven healthy participants were recruited to the study. The manipulation was successful, as during the nocebo learning phase, increased scratching responses were found for higher intensity compared with lower intensity itch stimuli. During the testing phase of induction or reversion of the nocebo effect, however, no significant nocebo effects or reversed nocebo effects, were found in scratching. Thus, no straightforward generalization of nocebo effects from itch to scratching was found in this laboratory setting. Further investigation into possible generalization is needed in different settings and in patients with chronic itch.

  16. Crack propagation and the material removal mechanism of glass-ceramics by the scratch test.

    PubMed

    Qiu, Zhongjun; Liu, Congcong; Wang, Haorong; Yang, Xue; Fang, Fengzhou; Tang, Junjie

    2016-12-01

    To eliminate the negative effects of surface flaws and subsurface damage of glass-ceramics on clinical effectiveness, crack propagation and the material removal mechanism of glass-ceramics were studied by single and double scratch experiments conducted using an ultra-precision machine. A self-manufactured pyramid shaped single-grit tool with a small tip radius was used as the scratch tool. The surface and subsurface crack propagations and interactions, surface morphology and material removal mechanism were investigated. The experimental results showed that the propagation of lateral cracks to the surface and the interaction between the lateral cracks and radial cracks are the two main types of material peeling, and the increase of the scratch depth increases the propagation angle of the radial cracks and the interaction between the cracks. In the case of a double scratch, the propagation of lateral cracks and radial cracks between paired scratches results in material peeling. The interaction between adjacent scratches depends on the scratch depth and separation distance. There is a critical separation distance where the normalized material removal volume reaches its peak. These findings can help reduce surface flaws and subsurface damage induced by the grinding process and improve the clinical effectiveness of glass-ceramics used as biological substitute and repair materials. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Effect of chemical etching and aging in boiling water on the corrosion resistance of Nitinol wires with black oxide resulting from manufacturing process.

    PubMed

    Shabalovskaya, S; Rondelli, G; Anderegg, J; Simpson, B; Budko, S

    2003-07-15

    The effect of chemical etching in a HF/HNO(3) acid solution and aging in boiling water on the corrosion resistance of Nitinol wires with black oxide has been evaluated with the use of potentiodynamic, modified potentiostatic ASTM F746, and scratch tests. Scanning-electron microscopy, elemental XPS, and Auger analysis were employed to characterize surface alterations induced by surface treatment and corrosion testing. The effect of aging in boiling water on the temperatures of martensitic transformations and shape recovery was evaluated by means of measuring the wire electroresistance. After corrosion tests, as-received wires revealed uniformly cracked surfaces reminiscent of the stress-corrosion-cracking phenomenon. These wires exhibited negative breakdown potentials in potentiostatic tests and variable breakdown potentials in potentiodynamic tests (- 100 mV to + 400 mV versus SCE). Wires with treated surfaces did not reveal cracking or other traces of corrosion attacks in potentiodynamic tests up to + 900-1400-mV potentials and no pitting after stimulation at + 800 mV in potentiostatic tests. They exhibited corrosion behavior satisfactory for medical applications. Significant improvement of corrosion parameters was observed on the reverse scans in potentiodynamic tests after exposure of treated wires to potentials > 1000 mV. In scratch tests, the prepared surfaces repassivated only at low potentials, comparable to that of stainless steel. Tremendous improvement of the corrosion behavior of treated Nitinol wires is associated with the removal of defect surface material and the growth of stable TiO(2) oxide. The role of precipitates in the corrosion resistance of Nitinol-scratch repassivation capacity in particular-is emphasized in the discussion. Copyright 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 66B: 331-340, 2003

  18. Discrete Element Modeling of Micro-scratch Tests: Investigation of Mechanisms of CO2 Alteration in Reservoir Rocks

    NASA Astrophysics Data System (ADS)

    Sun, Zhuang; Espinoza, D. Nicolas; Balhoff, Matthew T.; Dewers, Thomas A.

    2017-12-01

    The injection of CO2 into geological formations leads to geochemical re-equilibrium between the pore fluid and rock minerals. Mineral-brine-CO2 reactions can induce alteration of mechanical properties and affect the structural integrity of the storage formation. The location of alterable mineral phases within the rock skeleton is important to assess the potential effects of mineral dissolution on bulk geomechanical properties. Hence, although often disregarded, the understanding of particle-scale mechanisms responsible for alterations is necessary to predict the extent of geomechanical alteration as a function of dissolved mineral amounts. This study investigates the CO2-related rock chemo-mechanical alteration through numerical modeling and matching of naturally altered rocks probed with micro-scratch tests. We use a model that couples the discrete element method (DEM) and the bonded particle model (BPM) to perform simulations of micro-scratch tests on synthetic rocks that mimic Entrada sandstone. Experimental results serve to calibrate numerical scratch tests with DEM-BPM parameters. Sensitivity analyses indicate that the cement size and bond shear strength are the most sensitive microscopic parameters that govern the CO2-induced alteration in Entrada sandstone. Reductions in cement size lead to decrease in scratch toughness and an increase in ductility in the rock samples. This work demonstrates how small variations of microscopic bond properties in cemented sandstone can lead to significant changes in macroscopic large-strain mechanical properties.

  19. Value of the pinnal-pedal reflex in the diagnosis of canine scabies.

    PubMed

    Mueller, R S; Bettenay, S V; Shipstone, M

    2001-05-19

    The potential value of the pinnal-pedal scratch reflex as an aid to diagnosing canine scabies was assessed in 588 dogs with skin disease. The reflex was assessed by vigorously rubbing the tip of one earflap on to the base of the ear for five seconds, and it was considered positive if the ipsilateral hind leg made a scratching movement. A diagnosis of scabies was based on the dog's history, a physical examination and either positive skin scrapings or the complete resolution of pruritus and dermatitis after treatment with ivermectin or milbemycin, with no relapse for at least 12 months. Scabies was diagnosed in 55 of the dogs, allergic skin disease in 463, and 70 had other miscellaneous skin diseases. There was a positive pinnal-pedal scratch reflex in 45 (82 per cent) of the 55 dogs with scabies. Forty (73 per cent) of the dogs with scabies had pinnal dermatitis, and 36 (90 per cent) of these had a positive pinnal-pedal scratch reflex. There was a positive pinnal-pedal scratch reflex in 33 (6.2 per cent) of the other 533 dogs. On the basis of these results, the specificity of testing for scabies by the pinnal-pedal scratch reflex was 93.8 per cent, and the sensitivity was 81.8 per cent The test's positive predictive value was 0.57 and its negative predictive value was 0.98.

  20. Endometrial 'scratching': what the data show.

    PubMed

    Santamaria, Xavier; Katzorke, Nora; Simón, Carlos

    2016-08-01

    Since its first description in 2003, the endometrial scratching procedure has been the topic of over 1000 studies. This procedure, used to improve endometrial receptivity for assisted reproduction, is accessible - any gynecologist can easily perform it - and has been adapted into clinical routine by some reproductive units. However, the available data are controversial, and no biological plausibility exists to support the use of this intervention. This study aims to critically review the existing data, focusing on the last 2 years, regarding the efficiency of endometrial scratching. A total of five randomized controlled studies, one meta-analysis, and a systematic review related to endometrial scratching/injury were published in 2014 and 2015. Considerable heterogeneity exists among these studies regarding the selected population, type of treatment, and even timing and devices used to perform the endometrial injury. Importantly, none of these studies reported improved reproductive outcomes in terms of live birth rates following endometrial scratching. Overall, data from properly designed and powered randomized controlled studies demonstrate no beneficial effect of this intervention that is based on unknown biological effects. Endometrial scratching produces pain, costs money, and the side-effects of systematic scratching in the production of Asherman syndrome remain to be seen. Think before scratching.

  1. The Effect of Scratch-Based Game Activities on Students' Attitudes, Self-Efficacy and Academic Achievement

    ERIC Educational Resources Information Center

    Korkmaz, Özgen

    2016-01-01

    The purpose of the present research is to designate the effects of Scratch-based game activities on students' attitudes towards learning computer programming, self-efficacy beliefs and levels of academic achievement. The research was conducted through a pre-test-post-test control group quasi-experimental study. The study group consists of 49…

  2. Influence of subsurface defects on damage performance of fused silica in ultraviolet laser

    NASA Astrophysics Data System (ADS)

    Huang, Jin; Zhou, Xinda; Liu, Hongjie; Wang, Fengrui; Jiang, Xiaodong; Wu, Weidong; Tang, Yongjian; Zheng, Wanguo

    2013-02-01

    In ultraviolet pulse laser, damage performance of fused silica optics is directly dependent on the absorptive impurities and scratches in subsurface, which are induced by mechanical polishing. In the research about influence of subsurface defects on damage performance, a series of fused silica surfaces with various impurity concentrations and scratch structures were created by hydrofluoric (HF) acid solution etching. Time of Flight secondary ion mass spectrometry and scanning probe microprobe revealed that with increasing etching depth, impurity concentrations in subsurface layers are decreased, the scratch structures become smoother and the diameter:depth ratio is increased. Damage performance test with 355-nm pulse laser showed that when 600 nm subsurface thickness is removed by HF acid etching, laser-induced damage threshold of fused silica is raised by 40 percent and damage density is decreased by over one order of magnitude. Laser weak absorption was tested to explain the cause of impurity elements impacting damage performance, field enhancement caused by change of scratch structures was calculated by finite difference time domain simulation, and the calculated results are in accord with the damage test results.

  3. Scratch Testing of Hot-Pressed Monolithic Chromium Diboride (CrB2) and CrB2 + MoSi2 Composite

    NASA Astrophysics Data System (ADS)

    Bhatt, B.; Murthy, T. S. R. Ch.; Singh, K.; Sashanka, A.; Vishwanadh, B.; Sonber, J. K.; Sairam, K.; Nageswara Rao, G. V. S.; Srinivasa Rao, T.; Kain, Vivekanand

    2017-10-01

    The tribological performance of hot-pressed monolithic CrB2 and a newly developed CrB2 + 20 vol.% MoSi2 composite was investigated by using scratch test. The test was carried out under progressive loading ranging from 0.9 to 30 N over a scratch distance of 3 mm. In situ values of coefficient of friction (COF), depth of penetration and acoustic emission were recorded. The wear volume and fracture toughness were also calculated. COF of both materials is increased with increasing the scratch length and progressive load. COF of the composite was observed to be slightly higher compared to the monolithic CrB2. The wear volume of the composite is 60% higher compared to monolithic CrB2. Fracture toughness values of 2.48 and 2.81 MPa m1/2 were calculated for monolithic CrB2 and CrB2 + 20 vol.% MoSi2 composite, respectively. Microstructural characterization indicates that the abrasive wear is the dominant wear mechanism in both the materials.

  4. Scratching technique for the study and analysis of soil surface abrasion mechanism

    NASA Astrophysics Data System (ADS)

    Ta, Wanquan

    2007-11-01

    Aeolian abrasion is the most fundamental and active surface process that takes place in arid and semi-arid environments. Its nature is a wear process for wind blown grains impinging on a soil or sediment surface, which causes particles and aggregates to fracture from the soil surface through a series of plastic and brittle cracking deformation such as cutting, ploughing and brittle fracturing. Using a Universal Micro-Tribometer (UMT), a scratching test was carried out on six soil surfaces (sandy soil, sand loam, silt loam, loam, silt clay loam, and silt clay). The results indicate that traces of normal and tangential force vs. time show a jagged curve, which can reflect the plastic deformation and brittle fracturing of aggregates and particles of various sizes fractured from the soil surfaces. The jagged curve peaks, and the area enclosed underneath, may represent the bonding forces and bonding energies of some aggregates and grains on the soil surface, respectively. Connecting the scratching test with an impact abrasion experiment furthermore demonstrates that soil surface abrasion rates are proportional to the square of speeds of impacting particles and to the 2.6 power of mean soil grain size, and inversely proportional to the 1.5 power of specific surface abrasive energy or to the 1.7 power of specific surface hardness.

  5. Electrochemical behavior of Al in a non-aqueous alkyl carbonate solution containing LiBOB salt

    NASA Astrophysics Data System (ADS)

    Myung, Seung-Taek; Natsui, Hiroshi; Sun, Yang-Kook; Yashiro, Hitoshi

    Aluminum was studied as a current collector for rechargeable lithium batteries to understand electrochemical and passivation behavior. Electrochemical polarization tests, in situ scratch polarization tests and time-of-flight secondary ion mass spectroscopy (ToF-SIMS) analysis in lithium bis-oxalato borate (LiBOB)-containing alkyl carbonate solution were conducted. The Al foil did not follow the alloy and de-alloy process with the LiBOB salt in electrolyte at 0 V vs. Li/Li + in the cathodic sweep. During the anodic scan to the noble direction, the absence of an oxidation peak up to 3 V vs. Li/Li + indicated that the air-formed oxide layer of Al was not reduced to metal. Oxide-free Al surfaces made by the in situ scratch test during the electrochemical polarization resulted in abrupt alloy formation with Li at 0 V vs. Li/Li +, but the newly formed surface formed passive films at higher potential with oxygen, namely, Al-O compound, as confirmed by ToF-SIMS.

  6. Therapeutic Efficacy of Endometrial Scratching in Repeated Controlled Ovarian Stimulation (COS) Failure Cycles

    PubMed Central

    Wadhwa, Leena; Mishra, Mona

    2018-01-01

    Objective: The objective of the study was (1) “to evaluate the therapeutic efficacy of endometrial scratching in repeated controlled ovarian stimulation (COS) failure cycles.” And (2) “to compare differences in pregnancy outcome by endometrial scratching in early (D2–D4) and late follicular phases (D7–D9) of the same stimulation cycle.” Materials and Methods: Women attending infertility clinic in a tertiary care center and who have two or more repeated COS failure cycles and planned for COS with intrauterine insemination (IUI) were included in the study which is a prospective parallel, interventional, single-blinded, randomized control study, in 1:1 allocation ratio. A total of 165 patients were recruited and randomly allocated into three groups: Group A (n = 55) underwent endometrial scratching on D2–D4 of the same COS cycle, Group B (n = 55) on D7–D9, and Group C (n = 55) no intervention done. All the patients underwent COS according to standard protocol followed by IUI. Results: Clinical pregnancy rate was 12.73% (odds ratio [OR] =0.87 95% confidence interval [CI] =0.288–2.55, P = 1), 16.36% (OR = 1.15; 95% CI = 0.40–3.23, P = 1), and 14.54%, respectively, in Group A, B, and C, respectively (P = 0.86), as per intention to treat analysis. Using Chi-square test, P value between Group A and B was 0.787, between Group A and C was 1.000, and between Group B and C was 1.000. As per protocol analysis, clinical pregnancy rate was 13.46% (OR = 0.83; 95% CI = 0.27–2.5, P = 0.74), 19.57% (OR = 1.3 95%; CI = 0.45–3.73, P = 0.41), and 15.69%. Using Chi-square test, Pvalue between Group A and B was 0.588, between Group A and C was 0.967, and between Group B and C was 0.815. No abortions and multiple pregnancies occurred in either of the groups. Conclusion: The effect found was of good quantum in Group B as per protocol analysis which could be of clinical relevance if larger sample size would have been taken. Endometrial scratching is a cost-effective and easy technique which may improve clinical pregnancy rates in previous COS failure cycles, but more trials are needed to be conducted using larger sample size to achieve the improved and significant outcome. PMID:29681718

  7. SLIDING DIRECTION-DEPENDENCE OF POLYETHYLENE WEAR FOR METAL COUNTERFACE TRAVERSE OF SEVERE SCRATCHES

    PubMed Central

    Glennon, Liam P.; Baer, Thomas E.; Martin, James A.; Lack, William D.; Brown, Thomas D.

    2008-01-01

    Third body effects appear to be responsible for an appreciable portion of the wear rate variability within cohorts of patients with metal-on-polyethylene joint replacements. The parameters dominating the rate of polyethylene debris liberation by counterface scratches are not fully understood, but one seemingly contributory factor is the scratch’s orientation relative to the direction of instantaneous local surface sliding. To study this influence, arrays of 550 straight parallel scratches each representative of the severe end of the clinical range were diamond stylus-ruled onto the surface of polished stainless steel plates. These ruled plates were then worn reciprocally against polyethylene pins (both conventional and highly cross-linked) at traverse angles varied parametrically relative to the scratch direction. Wear was measured gravimetrically, and particulate debris was harvested and morphologically characterized. Both of the polyethylene variants tested showed pronounced wear rate peaks at acute scratch traverse angles (15º for conventional, 5º for cross-linked), and had nominally comparable absolute wear rate magnitudes. The particulate debris from this very aggressive test regime primarily consisted of extremely large and elongated strands, often tens or even hundreds of microns in length. These data suggest that counterface damage regions with preferential scratch directionality can liberate large amounts of polyethylene debris, apparently by a slicing/shearing mechanism, at critical (acute) attack angles. However, the predominant manifestation of this wear volume was in the form of particles far beyond the most osteolytically potent size range. PMID:19045513

  8. Quality Evaluation of Coatings by Automatic Scratch Testing

    DTIC Science & Technology

    1989-11-01

    MTL TR 89-98 IADII QUALITY EVALUATION OF COATINGS BY AUTOMATIC SCRATCH TESTING KIRIT J. BHANSALI LBRTR A1 U.S. ARMY MATERIALS TECHNOLOGY LABORATORY...distribution unlimited. LABORATORY COMMANO U.S. ARMY MATERIALS TECHNOLOGY LABORATORY PMUNKS wcamaauv LUaAMUv Watertown, Massachusetts 02172-0001 .o...Theo 7- Kattamis* 9 PEWNWING ORGANIZATION NAME AMO ADDRESS 1.PORUEEET RJC.TS AREA & WORK UNIT NUMSS U.S. Army Materials Technology Laboratory Watertown

  9. [Comparison of anti-angiogenic effect in vitro between ranibizumab and bevacizumab].

    PubMed

    Souto, Alexandre Cupello; Maricato, Juliana Terzi; Denapoli, Priscila Martins Andrade; Sallum, Juliana Maria Ferraz; Han, Sang Won

    2011-01-01

    To evaluate the comparative in-vitro antiangiogenic effect of Bevacizumab and Ranibizumab. Endothelial venous umbilical cells culture (ECV304) cultivated in F12 media with addition of 10% Fetal Bovine Serum, were plaqued and treated with clinically relevant concentrations of Bevacizumab and Ranibizumab just after the scratch done in the middle of the culture (scratch methodology). Measurements of the linear size of the area free of cell proliferation were done 24, 48 and 72 hours after the scratch day point. All the experiments were done in triplicate and statistical analysis were done with T-student test. Inhibitory effect was observed just at the concentrations of 0.5 and 0.7 mg/ml in both drugs. At 0.7 mg/ml, Ranibizumab demonstrated a more potent proliferative inhibitory effect than Bevacizumab. At the same concentration, Ranibizumab was three times more potent than Ranibizumab. Inhibitory effect was observed just in the first 24 hours for both drugs. Ranibizumab demonstrates an increased effect when compared to Bevacizumab and this is related more to the different molar rate of each drug than related to a real better proliferative inhibitory effect.

  10. Fabrication of Nanoscale Pits with High Throughput on Polymer Thin Film Using AFM Tip-Based Dynamic Plowing Lithography

    NASA Astrophysics Data System (ADS)

    He, Yang; Geng, Yanquan; Yan, Yongda; Luo, Xichun

    2017-09-01

    We show that an atomic force microscope (AFM) tip-based dynamic plowing lithography (DPL) approach can be used to fabricate nanoscale pits with high throughput. The method relies on scratching with a relatively large speed over a sample surface in tapping mode, which is responsible for the separation distance of adjacent pits. Scratching tests are carried out on a poly(methyl methacrylate) (PMMA) thin film using a diamond-like carbon coating tip. Results show that 100 μm/s is the critical value of the scratching speed. When the scratching speed is greater than 100 μm/s, pit structures can be generated. In contrast, nanogrooves can be formed with speeds less than the critical value. Because of the difficulty of breaking the molecular chain of glass-state polymer with an applied high-frequency load and low-energy dissipation in one interaction of the tip and the sample, one pit requires 65-80 penetrations to be achieved. Subsequently, the forming process of the pit is analyzed in detail, including three phases: elastic deformation, plastic deformation, and climbing over the pile-up. In particular, 4800-5800 pits can be obtained in 1 s using this proposed method. Both experiments and theoretical analysis are presented that fully determine the potential of this proposed method to fabricate pits efficiently.

  11. Fabrication of Nanoscale Pits with High Throughput on Polymer Thin Film Using AFM Tip-Based Dynamic Plowing Lithography.

    PubMed

    He, Yang; Geng, Yanquan; Yan, Yongda; Luo, Xichun

    2017-09-22

    We show that an atomic force microscope (AFM) tip-based dynamic plowing lithography (DPL) approach can be used to fabricate nanoscale pits with high throughput. The method relies on scratching with a relatively large speed over a sample surface in tapping mode, which is responsible for the separation distance of adjacent pits. Scratching tests are carried out on a poly(methyl methacrylate) (PMMA) thin film using a diamond-like carbon coating tip. Results show that 100 μm/s is the critical value of the scratching speed. When the scratching speed is greater than 100 μm/s, pit structures can be generated. In contrast, nanogrooves can be formed with speeds less than the critical value. Because of the difficulty of breaking the molecular chain of glass-state polymer with an applied high-frequency load and low-energy dissipation in one interaction of the tip and the sample, one pit requires 65-80 penetrations to be achieved. Subsequently, the forming process of the pit is analyzed in detail, including three phases: elastic deformation, plastic deformation, and climbing over the pile-up. In particular, 4800-5800 pits can be obtained in 1 s using this proposed method. Both experiments and theoretical analysis are presented that fully determine the potential of this proposed method to fabricate pits efficiently.

  12. Is scratch-cooking a cost-effective way to prepare healthy school meals with US Department of Agriculture foods?

    PubMed

    Woodward-Lopez, Gail; Kao, Janice; Kiesel, Kristin; Lewis Miller, Markell; Boyle, Maria; Drago-Ferguson, Soledad; Braff-Guajardo, Ellen; Crawford, Patricia

    2014-09-01

    Despite the resurgence of interest in scratch-cooking as a way to increase the quality and appeal of school meals, many school districts are concerned about the cost implications of switching to scratch-cooking. US Department of Agriculture (USDA) Foods are the single largest source of ingredients for school meals, and about half of USDA Foods are diverted for processing before being sent to the school district. We aimed to determine whether school lunch entrées made in a district from basic or raw USDA Foods ingredients can be healthier and less expensive to prepare than those sent to external processors. This cross-sectional study examined the relationship between the extent of scratch-cooking and the nutritional content and cost to prepare entrées. Information was gathered by interview with school foodservice personnel and from school foodservice records from a convenience sample of 10 school districts in California that employed varying degrees of scratch-cooking and is diverse in terms of geographic location and the sociodemographics of the student body. The sample included all elementary school lunch entrées that contain USDA Foods offered during October 2010 for a total sample of 146 entrées. Ordinary least squares regressions were used to test for statistically significant differences in cost and nutrient content of entrées according to the level of scratch-cooking. There was no significant relationship between total costs and level of scratch-cooking. Entrées with the highest scratch-cooking scores had significantly lower food costs, higher labor costs, and not significantly different total costs compared with entrées with no scratch-cooking. Nutrient content was not consistently associated with scratch-cooking, but scratch-cooked entrées did include a larger variety of non-fast-food-type entrées. The findings suggest that scratch-cooking can be a cost-effective way to expand the variety of healthy school lunches prepared with USDA Foods. Copyright © 2014 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

  13. Occupational protein contact dermatitis in food handlers.

    PubMed

    Hjorth, N; Roed-Petersen, J

    1976-02-01

    The preparation of food in restaurant kitchens carries a high risk of occupational dermatoses. Analysis of 33 cases revealed four different etiological types. Simple irritant dermatitis was rare (2 cases), plain contact dermatitis was more common (6 cases). Fifteen patients had relevant patch tests and scratch tests; ten had positive scratch tests only to explain the cause of their dermatitis. The last type was termed protein contact dermatitis. The major type IV allergens incriminated were metals, onion and garlic. The major proteinaceous allergens indicated by history and test results were fish and shell-fish. Open patch tests with the incriminated foods may cause erythema or oedema on normal skin after 20 minutes. Previously eczematous, now normal looking, skin often responds with a crop of dyshidrotic vesicles preceded by erythema and itching 30 minutes after the application of an open test. Examination for specific IgE is not always positive in such cases. Inhalant allergy was rare. The results indicate that food handlers are sensitized by the protein they touch, and then react to later contact with the proteins. Protein contact dermatitis is similarly common among veterinary surgeons, while the importance in other occupational groups remains to be studied.

  14. Cat scratch disease during pregnancy.

    PubMed

    Bilavsky, Efraim; Amit, Sharon; Avidor, Boaz; Ephros, Moshe; Giladi, Michael

    2012-03-01

    To describe the pregnancy outcome, including long-term follow-up of the offspring, of pregnant women with cat scratch disease. A surveillance study performed over 19 years identified eight pregnant women with cat scratch disease. A case of cat scratch disease was defined as a patient with a history of cat contact with regional lymphadenitis, other manifestations, or a combination of these consistent with the disease and one or more confirmatory laboratory tests. The clinical and laboratory manifestations and pregnancy outcome of all women diagnosed with cat scratch disease during pregnancy are described. Five of the eight pregnant women had typical disease with regional lymphadenitis; two had regional lymphadenitis with arthralgia, myalgia, and erythema nodosum; and one had neuroretinitis. Delayed diagnosis was common, although all women had a history of recent cat exposure. One woman who presented with clinical cat scratch disease during the first month of pregnancy had a spontaneous abortion. Another elected to terminate the pregnancy because of concerns related to radiation associated with abdominal computed tomography scan performed as part of an evaluation for suspected malignancy. The other six women gave birth to healthy newborns without congenital anomalies. No sequelae were recorded in mothers or children during a median follow-up of 4.5 years (range 0.5-9.5 years). With the exception of one early spontaneous abortion in which causality to cat scratch disease could not be established, neither deleterious effects of cat scratch disease on newborns nor reports of long-term sequelae were found. Physicians, especially family physicians and obstetrician-gynecologists need to be more familiar with the clinical manifestations of cat scratch disease. Close monitoring of infected women during pregnancy is advisable until more data are available to determine the optimal diagnostic and therapeutic approach.

  15. The Mars Environmental Compatibility Assessment (MECA) Abrasion Tool

    NASA Technical Reports Server (NTRS)

    Kuhlman, K. R.; Anderson, M. S.; Hinde, B. D.; Hecht, M. H.; Pike, W. T.; Marshall, J. R.; Meloy, T. P.

    1999-01-01

    The Mars Environmental Compatibility Assessment (MECA) experiment, an instrument suite to be flown on Mars Surveyor 2001, will include a tool for doing simple mineralogical scratch and streak tests on particles from the Martian regolith. The Abrasion Tool will be applied to particles that adhere themselves to highly polished substrates of various hardnesses. Granular soil components will be subjected to a compressive force of about 3 N using a leaf spring. The spring will be applied with a paraffin actuator capable of a 0.76 mm throw to achieve a maximum displacement of about 7.5 mm at the tip of the tool. The pressure per grain will be dependent on the grain size, the number of grains that adhere to the substrate and the number of grains in compression. The pressure per particle is expected to be on the order of 100 MPa - 1 GPa. The MECA sample wheel containing the substrates will be rotated after the particles are placed in compression to produce scratches or pits. A primary goal of the Abrasion Tool is to identify quartz (Mohs' hardness = 7) using substrates of varying hardnesses. Quartz is considered hazardous to future human explorers of Mars because it can cause silicosis of the lungs if it is of respirable size. It is also hazardous to machinery, structures, and space suits because of its ability to abrade and scratch surfaces. Since large quantities of minerals harder than quartz are not expected, any scratches produced on polished quartz substrates might be reasonably attributed to quartz particles, although there may be minerals such as impact metamorphic diamond in the soils. Careful calibration of the tool will be necessary to ensure that grains are not overloaded; for example, a steel ball pressed into glass will produce a Hertzian fracture, even though it is softer than glass. Other minerals, such as magnetite (Mohs' hardness = 6.5) have been shown to scratch glass ceramics such as Zerodur (Mohs' hardness = 6.5). Thus, minerals can be differentiated: note that regardless of the mineral species, if any particle is harder than 6.5 it will certainly be an interesting discovery for both planetary geology and human exploration concerns. The scratches will be identified using the 6X optical microscope and profiled with the atomic force microscope included in the MECA instrument suite. Analysis of the scratch morphology will yield evidence concerning the shape of the particle responsible for producing each scratch. For example, angular grains should leave vertical cracks with microconchoidal lateral chipping, while rounded grains might leave chatter marks, or nested partial Hertzian cracks. Particle shape can thus be inferred from these indentation modes, as well as material hardness. In addition, particle size information may also be available if pits caused by rolling particles can be identified. Converse to scratching, the minerals may be crushed at their contact points, and be smeared onto the target substrates to leave what geologists refer to as "streaks". These are cold-welded trails of mineral material that have structure and color indicative of mineral composition. The AFM will determine the morphology of these streaks, while the microscope will ascertain the color. On the harder substrates, we might expect streaking to dominate; on the softer substrates, scratching may dominate. Progressions of material interactions across the substrate selection will be a valuable source of data for mineral discrimination. It should also be noted that many minerals have coatings (such as iron oxides), and these will have to be differentiated from the host mineral grains; laboratory tests will establish the effects of such coatings on the scratch results. Finally, we note that the microscope will provide corroborative data regarding likely mineral species by grain shapes, fracture patterns, surface textures, color, and UV fluorescence reactions. Additional information is contained in the original extended abstract.

  16. The Mars Environmental Compatibility Assessment MECA Abrasion Tool

    NASA Technical Reports Server (NTRS)

    Kuhlman, K. R.; Anderson, M. S.; Hinde, B. D.; Hecht, M. H.; Pike, W. T.; Marshall, J.; Meloy, T. P.; Cobbly, T.

    1999-01-01

    The Mars Environmental Compatibility Assessment (MECA) experiment, an instrument suite to be flown on Mars Surveyor 2001, will include a tool for doing simple mineralogical scratch and streak tests on particles from the Martian regolith. The Abrasion Tool will be applied to particles that adhere to highly polished substrates of various hardnesses. Granular soil components will be subjected to a compressive force of about 3 N using a leaf spring. The spring will be applied with a paraffin actuator capable of a 0.76 mm throw to achieve a maximum displacement of about 7.5 mm at the tip of the tool. The pressure per grain will be dependent on the grain size, the number of grains that adhere to the substrate and the number of grains in compression. The pressure per particle is expected to be on the order of 100 MPa - 1 GPa. The MECA sample wheel containing the substrates will be rotated after the particles are placed in compression to produce scratches or pits. A primary goal of the Abrasion Tool is to identify quartz (Mohs' hardness = 7) using substrates of varying hardnesses. Quartz is considered hazardous to future human explorers of Mars because it can cause silicosis of the lungs if it is of respirable size. It is also hazardous to machinery, structures, and space suits because of its ability to abrade and scratch surfaces. Since large quantities of minerals harder than quartz are not expected, any scratches produced on polished quartz substrates might be reasonably attributed to quartz particles, although there may be minerals such as impact metamorphic diamond in the soils. Careful calibration of the tool will be necessary to ensure that grains are not overloaded; for example, a steel ball pressed into glass will produce a Hertzian fracture, even though it is softer than glass. Other minerals, such as magnetite (Mohs'hardness = 6.5) have been shown to scratch glass ceramics such as Zerodur (Mohs' hardness = 6.5). Thus, minerals can be differentiated: note that regardless of the mineral species, if any particle is harder than 6.5 it will certainly be an interesting discovery for both planetary geology and human exploration concerns. The scratches will be identified using the 6X optical microscope and profiled with the atomic force microscope included in the MECA instrument suite. Analysis of the scratch morphology will yield evidence concerning the shape of the particle responsible for producing each scratch. For example, angular grains should leave vertical cracks with microconchoidal lateral chipping, while rounded grains might leave chattermarks, or nested partial Hertzian cracks. Particle shape can thus be inferred from these indentation modes, as well as material hardness. In addition, particle size information may also be available if pits caused by rolling particles can be identified. Converse to scratching, the minerals may be crushed at their contact points, and be smeared onto the target substrates to leave what geologists refer to as "streaks". These are coldwelded trails of mineral material that have structure and color indicative of mineral composition. The AFM will determine the morphology of these streaks, while the microscope will ascertain the color. On the harder substrates, we might expect streaking to dominate; on the softer substrates, scratching may dominate. Progressions of material interactions across the substrate selection will be a valuable source of data for mineral discrimination. It should also be noted that many minerals have coatings (such as iron oxides), and these will have to be differentiated from the host mineral grains; laboratory tests will establish the effects of such coatings on the scratch results. Finally, we note that the microscope will provide corroborative data regarding likely mineral species by grain shapes, fracture patterns, surface textures, colr, and UV fluorescence reactions.

  17. The effect of low-intensity pulsed ultrasound on wound healing using scratch assay in epithelial cells.

    PubMed

    Iwanabe, Yujiro; Masaki, Chihiro; Tamura, Akiko; Tsuka, Shintaro; Mukaibo, Taro; Kondo, Yusuke; Hosokawa, Ryuji

    2016-10-01

    Low-intensity pulsed ultrasound (LIPUS) is widely used in medical fields because it shortens the time required for biologic wound healing in fracture treatment. Also, in dental fields, LIPUS should be effectively employed for implant treatment. However, most of the relevant reports have been published on its effects on bone formation around implants, and the effects of LIPUS on soft tissue healing remain unclear. In the present study, we examined the effects of LIPUS on soft tissue healing using gingival epithelial cells. Gingival epithelial cells were cultured on a dish, followed by LIPUS exposure at a frequency of 3MHz for 15min. The cells were counted with a hemocytometer, and a scratch assay was conducted by measuring the closing area of the scratch wound using a microscope. Following LIPUS exposure, total RNA was collected for microarray analysis. In addition, real-time PCR was performed to examine the mRNA expression level of integrin α6β4. Furthermore, total protein was collected to examine the protein expression level of integrin α6β4 by western blotting. The cell count and scratch assay demonstrated that LIPUS exposure promoted cell proliferation and scratch-wound closure. Microarray analysis demonstrated the increased expression levels of adhesion-related genes, including integrin. Real-time PCR analysis demonstrated that LIPUS exposure significantly up-regulated the mRNA expression level of integrin α6β4. Western blotting showed intense staining of integrin α6β4. LIPUS exposure promotes wound closure in the scratch assay and up-regulates the expression level of integrin α6β4 as compared with the control. Copyright © 2016 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  18. Scratch and dig analysis for Metis mirrors surfaces defects evaluation

    NASA Astrophysics Data System (ADS)

    Špína, M.; Procháska, F.; Melich, R.

    2016-11-01

    The presented paper aims to theoretically analyze the possibilities, advantages and drawbacks of standard methods used for the assessment of optical surface defects (the so-called Scratch and Dig analysis). Based on the acquired knowledge, we design and apply a process of SaD analysis suitable for the evaluation of optical surfaces of mirrors of the space coronagraph Metis, whose manufacturing was successfully implemented within the Centre Toptec in the past period.

  19. A 31-year-old man with bilateral blurry vision and floaters.

    PubMed

    Abazari, Azin; Kaplowitz, Kevin; Sibony, Patrick

    2015-01-01

    We report a case of bilateral multifocal retinochoroiditis and bilateral optic disc edema in a patient with cat-scratch disease from Bartonella henselae. The patient initially had negative serologic testing. Repeat testing showed a markedly increased IgG and IgM convalescent titer and the development of a branch retinal artery and vein occlusion. In patients for whom there is a high clinical suspicion of cat-scratch disease, a convalescent titer should be obtained 2-3 weeks following a negative initial result.

  20. Simultaneous measurement of friction and wear in hip simulators.

    PubMed

    Haider, Hani; Weisenburger, Joel N; Garvin, Kevin L

    2016-05-01

    We propose and have evaluated a method to measure hip friction during wear testing on a popular multi-station hip simulator. A 6-degree-of-freedom load cell underneath the specimen sensed forces and torques during implant wear testing of simulated walking. This included internal-external and adduction-abduction rotations which are often neglected during friction testing on pendulum-type machines. Robust mathematical analysis and data processing provided friction estimates in three simultaneous orthogonal rotations, over extended multi-million cycle wear tests. We tested various bearing couples including metal-on-plastic, ceramic-on-plastic, and metal-on-metal material couples. In one test series, new and intentionally scratched CoCrMo 40-mm-diameter femoral heads were tested against conventional ultrahigh-molecular-weight polyethylene, highly cross-linked, and highly cross-linked with vitamin E versions. The scratching significantly increased friction and doubled the wear of all groups. Before scratching, friction levels for the aforementioned plastic groups were 0.056 ± 0.0060, 0.062 ± 0.0080, and 0.070 ± 0.0045, respectively, but after scratching increased to 0.088 ± 0.018, 0.076 ± 0.0066, and 0.082 ± 0.0049, respectively, all statistically significant increases (p = 0.00059, 0.00005, 0.0115, respectively). In another test series of 44-mm femoral head diameter hips, metal-on-plastic hips with conventional ultrahigh-molecular-weight polyethylene showed the lowest friction at 0.045 ± 0.0085, followed by highly cross-linked with 0.046 ± 0.0035 (not significantly different). In a ceramic-on-plastic design with conventional ultrahigh-molecular-weight polyethylene, higher friction 0.079 ± 0.0070 was measured likely due to that ceramic surface being rougher than usual. Metal-on-metal hips were compared without and with a TiN coating, resulting in 0.049 ± 0.014 and 0.097 ± 0.020 friction factors, respectively (statistically significant, p < 0.001), and the coating wore away on all coated hips eventually. Higher friction mostly correlated with higher wear or damage to femoral heads or implant coatings, except for the highly cross-linked wear resistant ultrahigh-molecular-weight polyethylene which had slightly higher friction, confirming the same finding in other independent studies. This type of friction measurements can help screen for clamping and elevated wear of metal-on-metal and resurfacing total hip replacements, surgical malpositioning, and abraded and otherwise damaged surfaces. © IMechE 2016.

  1. 76 FR 6543 - Airworthiness Directives; Airbus Model A330-200 and -300 and A340-200 and -300 Series Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-07

    ... inspections for damage (such as a scratch, disbonding, or a tear) of the inner skin of the upper and lower... tear), and a tap test and a thermographic inspection to detect signs of moisture penetration, to the... detailed inspection for discrepancies (scratches, debonding, tears, and indications of trapped water), on...

  2. A Study of relationship between frailty and physical performance in elderly women.

    PubMed

    Jeoung, Bog Ja; Lee, Yang Chool

    2015-08-01

    Frailty is a disorder of multiple inter-related physiological systems. It is unclear whether the level of physical performance factors can serve as markers of frailty and a sign. The purpose of this study was to examine the relationship between frailty and physical performance in elderly women. One hundred fourteen elderly women participated in this study, their aged was from 65 to 80. We were measured 6-min walk test, grip-strength, 30-sec arm curl test, 30-sec chair stand test, 8 foot Up- and Go, Back scratch, chair sit and reach, unipedal stance, BMI, and the frailty with questionnaire. The collected data were analyzed by descriptive statistics, frequencies, correlation analysis, ANOVA, and simple liner regression using the IBM 21. SPSS program. In results, statistic tests showed that there were significant differences between frailty and 6-min walk test, 30-sec arm curl test, 30-sec chair stand test, grip-strength, Back scratch, and BMI. However, we did not find significant differences between frailty and 8 foot Up- and Go, unipedal stance. When the subjects were divided into five groups according to physical performance level, subjects with high 6-min walk, 30-sec arm curl test, chair sit and reach test, and high grip strength had low score frailty. Physical performance factors were strongly associated with decreased frailty, suggesting that physical performance improvements play an important role in preventing or reducing the frailty.

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

    Kilpi, Lauri, E-mail: Lauri.Kilpi@vtt.fi; Ylivaara, Oili M. E.; Vaajoki, Antti

    The scratch test method is widely used for adhesion evaluation of thin films and coatings. Usual critical load criteria designed for scratch testing of coatings were not applicable to thin atomic layer deposition (ALD) films on silicon wafers. Thus, the bases for critical load evaluation were established and the critical loads suitable for ALD coating adhesion evaluation on silicon wafers were determined in this paper as L{sub CSi1}, L{sub CSi2}, L{sub CALD1}, and L{sub CALD2}, representing the failure points of the silicon substrate and the coating delamination points of the ALD coating. The adhesion performance of the ALD Al{sub 2}O{submore » 3}, TiO{sub 2}, TiN, and TaCN+Ru coatings with a thickness range between 20 and 600 nm and deposition temperature between 30 and 410 °C on silicon wafers was investigated. In addition, the impact of the annealing process after deposition on adhesion was evaluated for selected cases. The tests carried out using scratch and Scotch tape test showed that the coating deposition and annealing temperature, thickness of the coating, and surface pretreatments of the Si wafer had an impact on the adhesion performance of the ALD coatings on the silicon wafer. There was also an improved load carrying capacity due to Al{sub 2}O{sub 3}, the magnitude of which depended on the coating thickness and the deposition temperature. The tape tests were carried out for selected coatings as a comparison. The results show that the scratch test is a useful and applicable tool for adhesion evaluation of ALD coatings, even when carried out for thin (20 nm thick) coatings.« less

  4. Endometrial scratch injury before intrauterine insemination: is it time to re-evaluate its value? Evidence from a systematic review and meta-analysis of randomized controlled trials.

    PubMed

    Vitagliano, Amerigo; Noventa, Marco; Saccone, Gabriele; Gizzo, Salvatore; Vitale, Salvatore Giovannni; Laganà, Antonio Simone; Litta, Pietro Salvatore; Saccardi, Carlo; Nardelli, Giovanni Battista; Di Spiezio Sardo, Attilio

    2018-01-01

    To assess the impact of endometrial scratch injury (ESI) on the outcomes of intrauterine insemination (IUI) stimulated cycles. Systematic review and meta-analysis. Not applicable. Infertile women undergoing one or more IUI stimulated cycles. Randomized controlled trials (RCTs) were identified by searching electronic databases. We included RCTs comparing ESI (i.e., intervention group) during the course of IUI stimulated cycle (C-ESI) or during the menstrual cycle preceding IUI treatment (P-ESI) with controls (no endometrial scratch). The summary measures were reported as odds ratio (OR) with 95% confidence-interval (CI). Clinical pregnancy rate, ongoing pregnancy rate, multiple pregnancy rate, ectopic pregnancy rate, miscarriage rate. Eight trials were included in the meta-analysis, comprising a total of 1,871 IUI cycles. Endometrial scratch injury was associated with a higher clinical pregnancy rate (OR 2.27) and ongoing pregnancy rate (OR 2.04) in comparison with the controls. No higher risk of multiple pregnancy (OR 1.09), miscarriage (OR 0.80), or ectopic pregnancy (OR 0.82) was observed in patients receiving ESI. Subgroup analysis based on ESI timing showed higher clinical pregnancy rate (OR 2.57) and ongoing pregnancy rate (OR 2.27) in patients receiving C-ESI and no advantage in patients receiving P-ESI. Available data suggest that ESI performed once, preferably during the follicular phase of the same cycle of IUI with flexible aspiration catheters, may improve clinical pregnancy and ongoing pregnancy rates in IUI cycles. Endometrial scratch injury does not appear to increase the risk of multiple pregnancy, miscarriage, or ectopic pregnancy. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  5. Effect of Bearing Defects

    DTIC Science & Technology

    1974-12-01

    defect types were tested at various levels: Comet- Tail, Dig-Nick, Dirt Brinell, Grind-Skip Lines, Impingement, Orange Peel , Pit, Scratch and "Liney...Shallow irregular indentation of surface. <.0015 max. dim. -(<.0008)*’ Otange Peel Pebbly appearance of raceway surface. Small ** Comet Tail Pit...scratch; dig-nick; impingement; grind-skip lines; and orange peel . The data obtained indicated that these defects in most cases, affected bearing

  6. Tribology Based Research and Training for Underrepresented Minorities

    DTIC Science & Technology

    2017-11-30

    images of surfaces after scratch hardness testing on NiTi with and without UNSM (left) and average scratch hardness measurements (right...the author(s) and should not contrued as an official Department of the Army position, policy or decision, unless so designated by other documentation...Minority Serving Institution, and its undergraduate students, as well as the predominantly Hispanic pre -college students from the Merced area, face many

  7. Monitoring of atopic dermatitis using leaky coaxial cable.

    PubMed

    Dong, Binbin; Ren, Aifeng; Shah, Syed Aziz; Hu, Fangming; Zhao, Nan; Yang, Xiaodong; Haider, Daniyal; Zhang, Zhiya; Zhao, Wei; Abbasi, Qammer Hussain

    2017-12-01

    In our daily life, inadvertent scratching may increase the severity of skin diseases (such as atopic dermatitis etc.). However, people rarely pay attention to this matter, so the known measurement behaviour of the movement is also very little. Nevertheless, the behaviour and frequency of scratching represent the degree of itching, and the analysis of scratching frequency is helpful to the doctor's clinical dosage. In this Letter, a novel system is proposed to monitor the scratching motion of a sleeping human body at night. The core device of the system is just a leaky coaxial cable (LCX) and a router. Commonly, LCX is used in the blind field or semi-blindfield in wireless communication. The new idea is that the leaky cable is placed on the bed, and then the state information of physical layer of wireless communication channels is acquired to identify the scratching motion and other small body movements in the human sleep process. The results show that it can be used to detect the movement and its duration. Channel state information (CSI) packet is collected by card installed in the computer based on the 802.11n protocol. The characterisation of the scratch motion in the collected CSI is unique, so it can be distinguished from the wireless channel amplitude variation trend.

  8. Monitoring of atopic dermatitis using leaky coaxial cable

    PubMed Central

    Dong, Binbin; Ren, Aifeng; Shah, Syed Aziz; Hu, Fangming; Zhao, Nan; Haider, Daniyal; Zhang, Zhiya; Zhao, Wei; Abbasi, Qammer Hussain

    2017-01-01

    In our daily life, inadvertent scratching may increase the severity of skin diseases (such as atopic dermatitis etc.). However, people rarely pay attention to this matter, so the known measurement behaviour of the movement is also very little. Nevertheless, the behaviour and frequency of scratching represent the degree of itching, and the analysis of scratching frequency is helpful to the doctor's clinical dosage. In this Letter, a novel system is proposed to monitor the scratching motion of a sleeping human body at night. The core device of the system is just a leaky coaxial cable (LCX) and a router. Commonly, LCX is used in the blind field or semi-blindfield in wireless communication. The new idea is that the leaky cable is placed on the bed, and then the state information of physical layer of wireless communication channels is acquired to identify the scratching motion and other small body movements in the human sleep process. The results show that it can be used to detect the movement and its duration. Channel state information (CSI) packet is collected by card installed in the computer based on the 802.11n protocol. The characterisation of the scratch motion in the collected CSI is unique, so it can be distinguished from the wireless channel amplitude variation trend. PMID:29383259

  9. Buccal dental-microwear and dietary ecology in a free-ranging population of mandrills (Mandrillus sphinx) from southern Gabon.

    PubMed

    Percher, Alice M; Romero, Alejandro; Galbany, Jordi; Nsi Akoue, Gontran; Pérez-Pérez, Alejandro; Charpentier, Marie J E

    2017-01-01

    Analyses of dental micro- and macro-wear offer valuable information about dietary adaptations. The buccal surface of the teeth does not undergo attrition, indicating that dental microwear may directly inform about food properties. Only a few studies have, however, investigated the environmental and individual factors involved in the formation of such microwear in wild animals. Here, we examine variation of buccal microwear patterns of mandibular molars in a large free-ranging population of mandrills (Mandrillus sphinx). We first explore the influence of seasonality and individual's sex, age and tooth macrowear-expressed as the percent of dentine exposure (PDE)-on six microwear variables. Second, we analyze the interplay between individual's diet and PDE. In a last analysis, we revisit our results on mandrills in the light of other primate's microwear studies. We show that the average buccal scratch length and the frequency of vertical buccal scratches are both higher during the long dry season compared to the long rainy season, while we observe the inverse relationship for disto-mesial scratches. In addition, females present more disto-mesial scratches than males and older individuals present higher scratch density, a greater proportion of horizontal scratches but a lower proportion of vertical scratches than young animals. PDE yields similar results than individual's age confirming earlier results in this population on the relationship between age and tooth macrowear. Because seasonality and individual characteristics are both known to impact mandrills' diet in the study population, our results suggest that buccal microwear patterns may inform about individual feeding strategies. Furthermore, PDE increases with the consumption of potentially abrasive monocotyledonous plants, independently of the individuals' age, although it is not affected by food mechanical properties. Finally, buccal scratch densities by orientation appear as relevant proxies for discriminating between different primate taxa.

  10. A comparative study of the mechanical behaviour of thermally oxidised commercially pure titanium and zirconium.

    PubMed

    Alansari, A; Sun, Y

    2017-10-01

    The objective of this study is to compare the mechanical behaviour of thermally oxidised commercially pure titanium (CP-Ti) and commercially pure zirconium (CP-Zr). For this purpose, these two bio-metals were thermally oxidised under the same condition (650°C for 6h) and the oxidised specimens were characterised using various analytical and experimental techniques, including oxygen uptake analysis, layer thickness and hardness measurements, scratch tests, dry sliding friction and wear tests and tribocorrosion tests in Ringer's solution. The results show that under the present thermal oxidation condition, 4 times more oxygen is introduced into CP-Zr than into CP-Ti and the oxide layer produced on CP-Zr is nearly 6 times thicker than that on CP-Ti. Thermally oxidised CP-Zr possesses a higher hardness, a deeper hardening depth and better scratch resistance than thermally oxidised CP-Ti. Under dry sliding and tribocorrosion conditions, thermally oxidised CP-Zr also possesses much better resistance to material removal and a higher load bearing capacity than thermally oxidised CP-Ti. Thus, thermally oxidised Zr possesses much better mechanical behaviour than thermally oxidised Ti. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. General Electromagnetic Model for the Analysis of Complex Systems (GEMACS) Engineering Manual (Version 3). Volume 3.

    DTIC Science & Technology

    1983-09-01

    processor. How- ever, upon completion of the restart initialization, additional commands may be added or original commands deleted with normal input...written IOSI Scratch logical unit designator IOS1SV Saved value of lOS1 IOS2 Scratch logical unit designator IR Index pointer to upper triangular matrix

  12. The Peaceful Co-existence of Input Frequency and Structural Intervention Effects on the Comprehension of Complex Sentences in German-Speaking Children

    PubMed Central

    Adani, Flavia; Stegenwallner-Schütz, Maja; Niesel, Talea

    2017-01-01

    The predictions of two contrasting approaches to the acquisition of transitive relative clauses were tested within the same groups of German-speaking participants aged from 3 to 5 years old. The input frequency approach predicts that object relative clauses with inanimate heads (e.g., the pullover that the man is scratching) are comprehended earlier and more accurately than those with an animate head (e.g., the man that the boy is scratching). In contrast, the structural intervention approach predicts that object relative clauses with two full NP arguments mismatching in number (e.g., the man that the boys are scratching) are comprehended earlier and more accurately than those with number-matching NPs (e.g., the man that the boy is scratching). These approaches were tested in two steps. First, we ran a corpus analysis to ensure that object relative clauses with number-mismatching NPs are not more frequent than object relative clauses with number-matching NPs in child directed speech. Next, the comprehension of these structures was tested experimentally in 3-, 4-, and 5-year-olds respectively by means of a color naming task. By comparing the predictions of the two approaches within the same participant groups, we were able to uncover that the effects predicted by the input frequency and by the structural intervention approaches co-exist and that they both influence the performance of children on transitive relative clauses, but in a manner that is modulated by age. These results reveal a sensitivity to animacy mismatch already being demonstrated by 3-year-olds and show that animacy is initially deployed more reliably than number to interpret relative clauses correctly. In all age groups, the animacy mismatch appears to explain the performance of children, thus, showing that the comprehension of frequent object relative clauses is enhanced compared to the other conditions. Starting with 4-year-olds but especially in 5-year-olds, the number mismatch supported comprehension—a facilitation that is unlikely to be driven by input frequency. Once children fine-tune their sensitivity to verb agreement information around the age of four, they are also able to deploy number marking to overcome the intervention effects. This study highlights the importance of testing experimentally contrasting theoretical approaches in order to characterize the multifaceted, developmental nature of language acquisition. PMID:29033863

  13. Numerical study of the influence of the thickness and roughness of TiN coatings on their wear in scratch testing

    NASA Astrophysics Data System (ADS)

    Eremina, G. M.; Smolin, A. Yu.

    2017-12-01

    One of the mostly used and complicated surgical operations on large human joints is total hip replacement. An endoprosthesis is chosen individually for each person on the basis of his anatomical features and physical activity. However, such an important factor affecting the durability of an endoprosthesis as wear in the head-acetabular cup friction pair is still poorly understood, and it is taken into account only qualitatively. The determining role in wear belongs to the structure of the surface layers and coatings of the friction pair. The mechanical and structural characteristics of the coating largely depend on the method of its application. In this paper, to study the tribological characteristics of the coating material of the friction pair, we use computer simulation of scratch testing. The simulations are performed with the application of the method of movable cellular automata. The model specimens correspond to real coatings manufactured under different treatment conditions (deposition temperature and time). The analysis of the simulation results allows one to choose the optimal regime corresponding to the maximum hardness of coatings or adhesive strength.

  14. Cat scratch disease and lymph node tuberculosis in a colon patient with cancer.

    PubMed

    Matias, M; Marques, T; Ferreira, M A; Ribeiro, L

    2013-12-12

    A 71-year-old man operated for a sigmoid tumour remained in the surveillance after adjuvant chemotherapy. After 3 years, a left axillary lymph node was visible on CT scan. The biopsy revealed a necrotising and abscessed granulomatous lymphadenitis, suggestive of cat scratch disease. The patient confirmed having been scratched by a cat and the serology for Bartonella henselae was IgM+/IgG-. Direct and culture examinations for tuberculosis were negative. The patient was treated for cat scratch disease. One year later, the CT scan showed increased left axillary lymph nodes and a left pleural effusion. Direct and cultural examinations to exclude tuberculosis were again negative. Interferon-γ release assay testing for tuberculosis was undetermined and then positive. Lymph node and pleural tuberculosis were diagnosed and treated with a good radiological response. This article has provides evidence of the importance of continued search for the right diagnosis and that two diagnoses can happen in the same patient.

  15. Hardness properties and microscopic investigation of crack- crystal interaction in SiO(2)-MgO-Al(2)O(3)-K(2)O-B(2)O(3)-F glass ceramic system.

    PubMed

    Roy, Shibayan; Basu, Bikramjit

    2010-01-01

    In view of the potential engineering applications requiring machinability and wear resistance, the present work focuses to evaluate hardness property and to understand the damage behavior of some selected glass-ceramics having different crystal morphologies with SiO(2)-MgO-Al(2)O(3)-K(2)O-B(2)O(3)-F composition, using static micro-indentation tests as well as dynamic scratch tests, respectively. Vickers hardness of up to 5.5 GPa has been measured in glass-ceramics containing plate like mica crystals. Scratch tests at a high load of 50 Nin artificial saliva were carried out in order to simulate the crack-microstructure interaction during real-time abrasion wear and machining operation. The experimental observations indicate that the novel "spherulitic-dendritic shaped "crystals, similar to the plate like crystals, have the potential to hinder the scratching induced crack propagation. In particular, such potential of the 'spherulitic-dendritic' crystals become more effective due to the larger interfacial area with the glass matrix as well as the dendritic structure of each mica plate, which helps in crack deflection and crack blunting, to a larger extent.While modest damage tolerant behavior is observed in case of 'spherulitic-dendritic' crystal containing material, severe brittle fracture of plate like crystals were noted, when both were scratched at 50 N load.

  16. Cat scratches, not bites, are associated with unipolar depression--cross-sectional study.

    PubMed

    Flegr, Jaroslav; Hodný, Zdeněk

    2016-01-05

    A recent study performed on 1.3 million patients showed a strong association between being bitten by a cat and probability of being diagnosed with depression. Authors suggested that infection with cat parasite Toxoplasma could be the reason for this association. A cross sectional internet study on a non-clinical population of 5,535 subjects was undertaken. The subjects that reported having been bitten by a dog and a cat or scratched by a cat have higher Beck depression score. They were more likely to have visited psychiatrists, psychotherapists and neurologists in past two years, to have been previously diagnosed with depression (but not with bipolar disorder). Multivariate analysis of models with cat biting, cat scratching, toxoplasmosis, the number of cats at home, and the age of subjects as independent variables showed that only cat scratching had positive effect on depression (p = 0.004). Cat biting and toxoplasmosis had no effect on the depression, and the number of cats at home had a negative effect on depression (p = 0.021). Absence of association between toxoplasmosis and depression and five times stronger association of depression with cat scratching than with cat biting suggests that the pathogen responsible for mood disorders in animals-injured subjects is probably not the protozoon Toxoplasma gondii but another organism; possibly the agent of cat-scratched disease - the bacteria Bartonella henselae.

  17. Displacement behaviors in chimpanzees (Pan troglodytes): A neurogenomics investigation of the RDoC Negative Valence Systems domain.

    PubMed

    Latzman, Robert D; Young, Larry J; Hopkins, William D

    2016-03-01

    The current study aimed to systematically investigate genetic and neuroanatomical correlates of individual variation in scratching behaviors, a well-validated animal-behavioral indicator of negative emotional states with clear links to the NIMH Research Domain Criteria (RDoC) response to potential harm ("anxiety") construct within the Negative Valence Systems domain. Utilizing data from a sample of 76 captive chimpanzees (Pan troglodytes), we (a) examined the association between scratching and presence or absence of the RS3-containing DupB element in the AVPR1A 5' flanking region, (b) utilized voxel-based morphometry (VBM) to identify gray matter (GM) voxel clusters that differentiated AVPR1A genotype, and (c) conducted a VBM-guided voxel-of-interest analysis to examine the association between GM intensity and scratching. AVPR1A evidenced sexually dimorphic associations with scratching. VBM analyses revealed significant differences in GM by genotype across twelve clusters largely in the frontal cortex. Regions differentiating AVPR1A genotype showed sex-specific associations with scratching. Results suggest that sexually dimorphic associations between AVPR1A and scratching may be explained by genotype-specific neuroanatomical variation. The current study provides an example of the way in which chimpanzee research is uniquely poised for multilevel, systematic investigations of psychopathology-relevant constructs within the context of the RDoC framework. © 2016 Society for Psychophysiological Research.

  18. A Study of relationship between frailty and physical performance in elderly women

    PubMed Central

    Jeoung, Bog Ja; Lee, Yang Chool

    2015-01-01

    Frailty is a disorder of multiple inter-related physiological systems. It is unclear whether the level of physical performance factors can serve as markers of frailty and a sign. The purpose of this study was to examine the relationship between frailty and physical performance in elderly women. One hundred fourteen elderly women participated in this study, their aged was from 65 to 80. We were measured 6-min walk test, grip-strength, 30-sec arm curl test, 30-sec chair stand test, 8 foot Up- and Go, Back scratch, chair sit and reach, unipedal stance, BMI, and the frailty with questionnaire. The collected data were analyzed by descriptive statistics, frequencies, correlation analysis, ANOVA, and simple liner regression using the IBM 21. SPSS program. In results, statistic tests showed that there were significant differences between frailty and 6-min walk test, 30-sec arm curl test, 30-sec chair stand test, grip-strength, Back scratch, and BMI. However, we did not find significant differences between frailty and 8 foot Up- and Go, unipedal stance. When the subjects were divided into five groups according to physical performance level, subjects with high 6-min walk, 30-sec arm curl test, chair sit and reach test, and high grip strength had low score frailty. Physical performance factors were strongly associated with decreased frailty, suggesting that physical performance improvements play an important role in preventing or reducing the frailty. PMID:26331137

  19. FROZEN RAW FOODS AS SKIN-TESTING MATERIALS—Further Studies of Use in Cases of Allergic Disorders

    PubMed Central

    Ancona, Giacomo R.; Schumacher, Irwin C.

    1954-01-01

    In further studies on the use of frozen raw food as skin-testing material in patients with allergic disorders, the results of previous work were confirmed in a greater number of subjects using a larger number of foods: Tests with frozen raw foods by the scratch method induce true positive reactions of a larger size and in greater frequency than the corresponding commercial extracts by either the scratch or the intracutaneous method. Storage in the frozen state for several years does not affect the antigenic potency of the materials. The frozen preparations have caused no harmful effects in the subjects, are free from irritant properties, and are not urticariogenic. PMID:13126823

  20. Determination of the Wound Healing Potentials of Medicinal Plants Historically Used in Ghana

    PubMed Central

    Freiesleben, Sara H.; Soelberg, Jens; Nyberg, Nils T.

    2017-01-01

    The present study was carried out to investigate the wound healing potentials of 17 medicinal plants historically used in Ghana for wound healing. Warm and cold water extracts were prepared from the 17 dried plant species and tested in vitro in the scratch assay with NIH 3T3 fibroblasts from mice. The wound healing scratch assay was used to evaluate the effect of the plants on cell proliferation and/or migration in vitro, as a test for potential wound healing properties. After 21 hours of incubation increased proliferation and/or migration of fibroblasts in the scratch assay was obtained for 5 out of the 17 plant species. HPLC separation of the most active plant extract, which was a warm water extract of Philenoptera cyanescens, revealed the wound healing activity to be attributed to rutin and a triglycoside of quercetin. The present study suggests that Allophylus spicatus, Philenoptera cyanescens, Melanthera scandens, Ocimum gratissimum, and Jasminum dichotomum have wound healing activity in vitro. PMID:28326125

  1. Effects of filler type and content on mechanical properties of photopolymerizable composites measured across two-dimensional combinatorial arrays.

    PubMed

    Lin-Gibson, Sheng; Sung, Lipiin; Forster, Aaron M; Hu, Haiqing; Cheng, Yajun; Lin, Nancy J

    2009-07-01

    Multicomponent formulations coupled with complex processing conditions govern the final properties of photopolymerizable dental composites. In this study, a single test substrate was fabricated to support multiple formulations with a gradient in degree of conversion (DC), allowing the evaluation of multiple processing conditions and formulations on one specimen. Mechanical properties and damage response were evaluated as a function of filler type/content and irradiation. DC, surface roughness, modulus, hardness, scratch deformation and cytotoxicity were quantified using techniques including near-infrared spectroscopy, laser confocal scanning microscopy, depth-sensing indentation, scratch testing and cell viability. Scratch parameters (depth, width, percent recovery) were correlated to composite modulus and hardness. Total filler content, nanofiller and irradiation time/intensity all affected the final properties, with the dominant factor for improved properties being a higher DC. This combinatorial platform accelerates the screening of dental composites through the direct comparison of properties and processing conditions across the same sample.

  2. Corneal ulcers and infections

    MedlinePlus

    ... eye Scratches (abrasions) on the eye surface Severely dry eyes Severe allergic eye disease Various inflammatory disorders Wearing ... response Refraction test Slit-lamp examination Tests for dry eye Visual acuity Blood tests to check for inflammatory ...

  3. Oxidation behavior of Al/Cr coating on Ti2AlNb alloy at 900 °C

    NASA Astrophysics Data System (ADS)

    Yang, Zhengang; Liang, Wenping; Miao, Qiang; Chen, Bowen; Ding, Zheng; Roy, Nipon

    2018-04-01

    In this paper, the Al/Cr coating was fabricated on the surface of Ti2AlNb alloy via rf magnetron sputtering and double glow treatment to enhance oxidation resistance. The protective coating with an outer layer of Al and inner layer of Cr has great bonding strength due to the in-diffusion of Cr and the inter-diffusion between Al and Cr to form Al-Cr alloyed layer which has great hardness. Acoustic emission curve which was detected via WS-2005 scratch tester indicates the bonding strength between Al/Cr coating and substrate is great. Morphology of Ti2AlNb alloy with Al/Cr coating after scratch test shows that the scratch is smooth without disbanding, and the depth and breadth of scratch are changed uniformly. The mass change was reduced after oxidation test due to the Al/Cr protective coating. Isothermal oxidation test at 900 °C was researched. Results indicate that Al/Cr coating provided oxidation resistance of Ti2AlNb alloy with prolonged air exposure at 900 °C. Al2O3 was detected by XRD patterns and SEM images, and was formed on the surface of Ti2AlNb alloy to protect substrate during oxidation test. A certain content of Cr is beneficial for the formation of Al2O3. Besides, Cr2O3 was produced under Al2O3 by outward diffusion of Cr to protect substrate sequentially, no cracks were discovered on Al/Cr protective coating. The process of Ti outward diffusion into surface was suppressive due to integration of Cr-Ti and Al-Ti intermetallics. A steady, adherent and continuous coated layer of Al/Cr on Ti2AlNb alloy increases oxidation resistance.

  4. Noble Logic for Preventing Scratch on Roll-to-Roll Printed Layers in Noncontacting Transportation

    NASA Astrophysics Data System (ADS)

    Lee, Changwoo; Kang, Hyunkyoo; Kim, Hojoon; Shin, Keehyun

    2010-05-01

    The use of roll-to-roll (R2R) printed electronics is a relatively new method of mass producing flexible electronic devices while keeping production costs down. The geometrical qualities of a printed pattern, such as surface roughness and uniformity, could deteriorate. Moreover, the geometric qualities of a printed layer affect the functional qualities of a printed electronic device directly. Therefore, the functional qualities (conductivity and mobility) of a multilayer electronic device could deteriorate in the presence of a scratch defect on the printed layer. In general, a scratch on a printed pattern on a flexible substrate is induced by contact between the rolls and printed pattern in R2R printing systems. To prevent such contact, one of the best solutions is to use an air flotation unit. However, a scratch defect could be induced even though an air flotation process is used to minimize contact, because the flotation height of a moving web is affected by web tension. In this paper, we discuss an analytical model of an air-floated moving substrate. For the noncontacting transfer of a moving web without a scratch defect, a mathematical tension model has been developed by considering an induced strain due to aerodynamic forces and verified by numerical and experimental studies. Additionally, the correlation between the flotation height of an air-floated moving web and speed compensation used to control the tension are investigated. The analysis shows that tension fluctuations can cause the substrate to touch the air-flotation subsystem, which is installed to prevent contact, resulting in defects such as scratches on the printed layer. On the basis of the proposed model, a logic is developed to minimize scratch defects on R2R printed layers in noncontacting transportation. Through a guideline based on this logic, the scratched area density on R2R printed layers can be reduced by approximately 70%.

  5. Buccal dental-microwear and dietary ecology in a free-ranging population of mandrills (Mandrillus sphinx) from southern Gabon

    PubMed Central

    Romero, Alejandro; Galbany, Jordi; Nsi Akoue, Gontran; Pérez-Pérez, Alejandro; Charpentier, Marie J. E.

    2017-01-01

    Analyses of dental micro- and macro-wear offer valuable information about dietary adaptations. The buccal surface of the teeth does not undergo attrition, indicating that dental microwear may directly inform about food properties. Only a few studies have, however, investigated the environmental and individual factors involved in the formation of such microwear in wild animals. Here, we examine variation of buccal microwear patterns of mandibular molars in a large free-ranging population of mandrills (Mandrillus sphinx). We first explore the influence of seasonality and individual’s sex, age and tooth macrowear–expressed as the percent of dentine exposure (PDE)–on six microwear variables. Second, we analyze the interplay between individual’s diet and PDE. In a last analysis, we revisit our results on mandrills in the light of other primate’s microwear studies. We show that the average buccal scratch length and the frequency of vertical buccal scratches are both higher during the long dry season compared to the long rainy season, while we observe the inverse relationship for disto-mesial scratches. In addition, females present more disto-mesial scratches than males and older individuals present higher scratch density, a greater proportion of horizontal scratches but a lower proportion of vertical scratches than young animals. PDE yields similar results than individual’s age confirming earlier results in this population on the relationship between age and tooth macrowear. Because seasonality and individual characteristics are both known to impact mandrills’ diet in the study population, our results suggest that buccal microwear patterns may inform about individual feeding strategies. Furthermore, PDE increases with the consumption of potentially abrasive monocotyledonous plants, independently of the individuals’ age, although it is not affected by food mechanical properties. Finally, buccal scratch densities by orientation appear as relevant proxies for discriminating between different primate taxa. PMID:29073184

  6. The role of the substrate in micro-scale scratching of epoxy-polyester films

    NASA Astrophysics Data System (ADS)

    Barletta, M.; Gisario, A.

    2011-02-01

    The present investigation analyzes the deformation response of electrostatically sprayed epoxy-polyester powder coatings by 'in situ' micro-mechanical tests. The characterization of the performance of the coatings was carried out by micro-scale scratching, by varying the indenter type, the applied load and the sliding speed. The tests were carried out on polymeric coatings deposited on as-received, micro and macro-corrugated AISI 304 stainless steel substrates and 'rigidly adhered' to them. Further tests were performed on 'free-standing' coatings, that is, on the as-received metal substrates pre-coated with an intermediate layer of silicon-based heat curable release coating. Experimental data allow us to evaluate the influence of the contact conditions between substrate and indenter and the role of the loading conditions on the scratch and penetration resistance of the epoxy-polyester coatings. The different responses of the polymeric coatings when deposited on untreated or pre-treated substrates as well as on an intermediate layer of release coating, contribute to a better understanding of the intrinsic roles of the polymeric material and substrate as well as the influence of the interfacial adhesion between coating and substrate.

  7. Convolutional Neural Networks for Medical Image Analysis: Full Training or Fine Tuning?

    PubMed

    Tajbakhsh, Nima; Shin, Jae Y; Gurudu, Suryakanth R; Hurst, R Todd; Kendall, Christopher B; Gotway, Michael B; Jianming Liang

    2016-05-01

    Training a deep convolutional neural network (CNN) from scratch is difficult because it requires a large amount of labeled training data and a great deal of expertise to ensure proper convergence. A promising alternative is to fine-tune a CNN that has been pre-trained using, for instance, a large set of labeled natural images. However, the substantial differences between natural and medical images may advise against such knowledge transfer. In this paper, we seek to answer the following central question in the context of medical image analysis: Can the use of pre-trained deep CNNs with sufficient fine-tuning eliminate the need for training a deep CNN from scratch? To address this question, we considered four distinct medical imaging applications in three specialties (radiology, cardiology, and gastroenterology) involving classification, detection, and segmentation from three different imaging modalities, and investigated how the performance of deep CNNs trained from scratch compared with the pre-trained CNNs fine-tuned in a layer-wise manner. Our experiments consistently demonstrated that 1) the use of a pre-trained CNN with adequate fine-tuning outperformed or, in the worst case, performed as well as a CNN trained from scratch; 2) fine-tuned CNNs were more robust to the size of training sets than CNNs trained from scratch; 3) neither shallow tuning nor deep tuning was the optimal choice for a particular application; and 4) our layer-wise fine-tuning scheme could offer a practical way to reach the best performance for the application at hand based on the amount of available data.

  8. Generation of Scratches and Their Effects on Laser Damage Performance of Silica Glass

    PubMed Central

    Li, Yaguo; Ye, Hui; Yuan, Zhigang; Liu, Zhichao; Zheng, Yi; Zhang, Zhe; Zhao, Shijie; Wang, Jian; Xu, Qiao

    2016-01-01

    Scratches are deleterious to precision optics because they can obscure and modulate incident laser light, which will increase the probability of damage to optical components. We here imitated the generation of brittle and ductile scratches during polishing process and endeavored to find out the possible influence of scratches on laser induced damage. Brittle scratches can be induced by spiking large sized abrasives and small abrasives may only generate ductile scratches. Both surface roughness and transmittivity are degraded due to the appearance of brittle scratches while ductile scratches make little difference to surface roughness and transmittance. However, ductile and brittle scratches greatly increase the density of damage about one order of magnitude relative to unscratched surface. In particular, ductile scratches also play an unignorable role in laser induced damage, which is different from previous knowledge. Furthermore, ZrO2 and Al2O3 polished surfaces appear to perform best in terms of damage density. PMID:27703218

  9. Influence of third-body particles originating from bone void fillers on the wear of ultra-high-molecular-weight polyethylene

    PubMed Central

    Cowie, Raelene M; Carbone, Silvia; Aiken, Sean; Cooper, John J; Jennings, Louise M

    2016-01-01

    Calcium sulfate bone void fillers are increasingly being used for dead space management in infected arthroplasty revision surgery. The presence of these materials as loose beads close to the bearing surfaces of joint replacements gives the potential for them to enter the joint becoming trapped between the articulating surfaces; the resulting damage to cobalt chrome counterfaces and the subsequent wear of ultra-high-molecular-weight polyethylene is unknown. In this study, third-body damage to cobalt chrome counterfaces was simulated using particles of the calcium sulfate bone void fillers Stimulan® (Biocomposites Ltd., Keele, UK) and Osteoset® (Wright Medical Technology, TN, USA) using a bespoke rig. Scratches on the cobalt chrome plates were quantified in terms of their density and mean lip height, and the damage caused by the bone void fillers was compared to that caused by particles of SmartSet GMV PMMA bone cement (DePuy Synthes, IN, USA). The surface damage from Stimulan® was below the resolution of the analysis technique used; SmartSet GMV caused 0.19 scratches/mm with a mean lip height of 0.03 µm; Osteoset® led to a significantly higher number (1.62 scratches/mm) of scratches with a higher mean lip height (0.04 µm). Wear tests of ultra-high-molecular-weight polyethylene were carried out in a six-station multi-axial pin on plate reciprocating rig against the damaged plates and compared to negative (highly polished) and positive control plates damaged with a diamond stylus (2 µm lip height). The wear of ultra-high-molecular-weight polyethylene was shown to be similar against the negative control plates and those damaged with third-body particles; there was a significantly higher (p < 0.001) rate of ultra-high-molecular-weight polyethylene wear against the positive control plates. This study showed that bone void fillers of similar composition can cause varying damage to cobalt chrome counterfaces. However, the lip heights of the scratches were not of sufficient magnitude to increase the wear of ultra-high-molecular-weight polyethylene above that of the negative controls. PMID:27312481

  10. Enhancement of as-sputtered silver-tantalum oxide thin film coating on biomaterial stainless steel by surface thermal treatment

    NASA Astrophysics Data System (ADS)

    Alias, Rodianah; Mahmoodian, Reza; Shukor, Mohd Hamdi Abd; Yew, Been Seok; Muhamad, Martini

    2018-04-01

    Stainless steel 316L (SS316L) is extensively used as surgical/clinical tools due to its low carbon content and excellent mechanical characteristic. The fabrication of metal ceramic based on this metallic biomaterial favor its biofunctionality properties. However, instability phase of amorphous thin film lead to degradation, corrosion and oxidation. Thus, thin film coating requires elevated adhesion strength and higher surface hardness to meet clinical tools criteria. In this study, the SS316L was deposited with micron thickness of Ag-TaO thin film by using magnetron sputtering. The microstructure, elemental analysis and phase identification of Ag-TaO thin film were characterized by using FESEM, EDX and XRD, respectively; whereas the micro scratch test and micro hardness test were performed by using Micro Scratch Testing System and Vickers Micro Hardness Tester, respectively. It was found that the coating thin film's adhesion and hardness strength were improved from 672 to 2749 mN and 142 to 158 Hv respectively. It was found that the as-deposited surface were treated at 500 °C of temperatures with 2 °C/min ramping rate enhance 4.1 times of the adhesion strength value. Furthermore, FESEM characterization revealed coarsening structure of the thin film coating which can provide high durability service.

  11. Enamel Insulated Copper Wire in Electric Motors: Sliding Behavior and Possible Damage Mechanisms During Die Bending

    NASA Astrophysics Data System (ADS)

    Demiri, Albion

    This study investigates the sliding friction and the forming behaviour of enamel insulated copper wire during the die-forming process. It also aims to determine potential damage mechanisms to the wire during bending process for electric motor coils. In this investigation a wire-bending machine was designed and built in order to simulate the wire forming process in a laboratory scale. Bending angle of the wire and the bending radii were used to control the strain on the wire surface. The effect of speed on COF was investigated for different speeds of of 1, 5, 10, 15, and 20mm/s. A positive correlation was observed between the COF and the testing speed. Additionally, the effect of strain on COF was studied for 2% and 23% to determine its influence on the COF. A general trend was observed of decreased COF with increased strain in wires. Finally, the ability of the enamel coating to resist external damage and wire strain was investigated by tensile testing of pre-scratched magnet wire. The results showed that wire enamel can withstand significant surface damage prior to breach and failure. The insulating polymer coating failed under the scratch tests at 20N load using a Rockwell indenter and at 5N load using a 90° conical steel indenter. Additional tests, such as tensile testing, scratch testing and reciprocating friction testing, were used to characterize the mechanical and tribological properties of the enamel insulated copper wire.

  12. Deformation relief induced by scratch testing on the surface of Hadfield steel

    NASA Astrophysics Data System (ADS)

    Lychagin, D. V.; Filippov, A. V.; Novitskaya, O. S.; Kolubaev, A. V.; Sizova, O. V.

    2017-12-01

    The paper is devoted to deformation relief formed on the surface of Hadfield steel while scratching under a linearly increasing load. The deformation relief is analyzed to detect regions with microfracture of the surface layer of Hadfield steel. Crack generation regions coincide with regions of the most intense acoustic emission (AE) signal. Single and multiple slip bands are observed in various grains of the material. As the load increases, slip bands thicken and grains with multiple slip are more frequent.

  13. Assessment of mechanical rock alteration caused by CO 2 -water mixtures using indentation and scratch experiments

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

    Sun, Yuhao; Aman, Michael; Espinoza, D. Nicolas

    CO2 injection into geological formations disturbs the geochemical equilibrium between water and minerals. Thus, some mineral phases are prone to dissolution and precipitation with ensuing changes of petrophysical and geomechanical properties of the host formations. Chemically-assisted degradation of mechanical properties can endanger the structural integrity of the storage formation and must be carefully studied and considered to guarantee safe long-term trapping. Few experimental data sets involving CO2 alteration and mechanical testing of rock samples are available since these experiments are length, expensive, and require specialized equipment and personnel. Autoclave experiments are easier to perform and control but result in amore » limited 'skin depth' of chemically-altered zone near the surface of the sample. This article presents the validation of micro-indentation and micro-scratch tests as efficient tools to assess the alteration of mechanical properties of rocks geochemically altered by CO2-water mixtures. Results from tests on sandstone and siltstone from Crystal Geyser, Utah naturally altered by CO2-acidified water show that mechanical parameters measured with indentation (indentation hardness, Young's modulus and contact creep compliance rate) and scratching (scratch hardness and fracture toughness) consistently indicated weakening of the rock after CO2-induced alteration. Decreases of measured parameters vary from 14% to 87%. Experimental results and analyses show that micromechanical tests are potentially quick and reliable tools to determine the change of mechanical properties of rocks subject to exposure to CO2-acidified water, particularly in well-controlled autoclave experiments. Measured parameters are not intended to provide inputs for coupled reservoir simulation with geomechanics but rather to inform the execution of larger scale tests investigating the susceptibility of rock facies to chemical alteration by CO2-water mixtures. Recognizing this susceptibility of rock facies of CO2 geological storage target formations is critical to controlling undesired emergent behavior associated with CO2 sequestration.« less

  14. Effect of Substrate Bias on Friction Coefficient, Adhesion Strength and Hardness of TiN-COATED Tool Steel

    NASA Astrophysics Data System (ADS)

    Hamzah, Esah; Ali, Mubarak; Toff, Mohd Radzi Hj. Mohd

    In the present study, TiN coatings have been deposited on D2 tool steel substrates by using cathodic arc physical vapor deposition technique. The objective of this research work is to determine the usefulness of TiN coatings in order to improve the micro-Vickers hardness and friction coefficient of TiN coating deposited on D2 tool steel, which is widely used in tooling applications. A Pin-on-Disc test was carried out to study the coefficient of friction versus sliding distance of TiN coating deposited at various substrate biases. The standard deviation parameter during tribo-test result showed that the coating deposited at substrate bias of -75 V was the most stable coating. A significant increase in micro-Vickers hardness was recorded, when substrate bias was reduced from -150 V to zero. Scratch tester was used to compare the critical loads for coatings deposited at different bias voltages and the adhesion achievable was demonstrated with relevance to the various modes, scratch macroscopic analysis, critical load, acoustic emission and penetration depth. A considerable improvement in TiN coatings was observed as a function of various substrate bias voltages.

  15. Preparation of polystyrene brush film by radical chain-transfer polymerization and micromechanical properties

    NASA Astrophysics Data System (ADS)

    Zhao, Jing; Chen, Miao; An, Yanqing; Liu, Jianxi; Yan, Fengyuan

    2008-12-01

    A radical chain-transfer polymerization technique has been applied to graft-polymerize brushes of polystyrene (PSt) on single-crystal silicon substrates. 3-Mercapto-propyltrimethoxysilane (MPTMS), as a chain-transfer agent for grafting, was immobilized on the silicon surface by a self-assembling process. The structure and morphology of the graft-functionalized silicon surfaces were characterized by the means of contact-angle measurement, ellipsometric thickness measurement, Fourier transformation infrared (FTIR) spectroscopy, and atomic force microscopy (AFM). The nanotribological and micromechanical properties of the as-prepared polymer brush films were investigated by frictional force microscopy (FFM), force-volume analysis and scratch test. The results indicate that the friction properties of the grafted polymer films can be improved significantly by the treatment of toluene, and the chemically bonded polystyrene film exhibits superior scratch resistance behavior compared with the spin-coated polystyrene film. The resultant polystyrene brush film is expected to develop as a potential lubrication coating for microelectromechanical systems (MEMS).

  16. The fracture strength of ceramic brackets: a comparative study.

    PubMed

    Flores, D A; Caruso, J M; Scott, G E; Jeiroudi, M T

    1990-01-01

    Recent demand for esthetic brackets has led to the development and use of ceramic brackets in orthodontics. The purpose of this study was to compare the fracture strength of different ceramic brackets under different surface conditions and ligation methods using a torsional wire bending force. Five different bracket types (two polycrystalline, two single-crystal, and one metal) were tested using elastic and wire ligation, with half being scratched and the other half remaining unscratched. Results showed a significant difference between bracket types and surface conditions. Non-scratched single-crystal brackets had higher fracture strengths and slightly higher fracture loads than polycrystalline brackets. However, single-crystal brackets were significantly adversely affected by surface damage (scratching), while polycrystalline brackets were not significantly affected by surface damage. The fracture behavior of ceramic brackets followed the Griffith model where fracture strength decreased following surface damage.

  17. Owner observations regarding cat scratching behavior: an internet-based survey.

    PubMed

    Wilson, Colleen; Bain, Melissa; DePorter, Theresa; Beck, Alexandra; Grassi, Vanessa; Landsberg, Gary

    2016-10-01

    This study was performed to examine aspects of the cat, environment and scratching post that might influence scratching behavior, in an effort to determine how inappropriate scratching behavior might be refocused on acceptable targets. An internet survey, posted on several public websites, gathered details about scratching behavior, as described by owners in their home environments, from 4331 respondents over a 4 month period. Responses from 39 different countries were analyzed, mostly from the USA, Canada and the UK. Owners offered traditionally recommended scratching substrates including rope, cardboard, carpet and wood. Rope was most frequently used when offered, although carpet was offered most commonly. Most owners provided at least one scratching post; cats scratched the preferred substrate more often when the post was a simple upright type or a cat tree with two or more levels and at least 3 ft high. Narrower posts (base width ⩽3 ft) were used more often than wider posts (base width ⩾5 ft). Intact or neutered cats (males and females) were as likely to scratch inappropriately, and inappropriate scratching decreased with age. Geriatric cats between the ages of 10 and 14 years preferred carpet substrate most frequently; all other ages preferred rope first. Inappropriate scratching decreased as the different types/styles of posts increased in the home. Inappropriate scratching did not increase if the number of cats or dogs increased in the household. Declawed cats were preventatively declawed most often to prevent household item destruction. Although cats can have individual preferences, our data provide a starting point for veterinarians recommending scratching posts to clients. © The Author(s) 2015.

  18. Occupational protein contact dermatitis from spices in a butcher: a new presentation of the mugwort-spice syndrome.

    PubMed

    Anliker, Mark David; Borelli, Siegfried; Wüthrich, Brunello

    2002-02-01

    Protein contact dermatitis to meat is well known in butchers; spices are another source of potential contact allergy and usually are not recognized. We present a first case of contact-dermatitis to spice mix in a 39-year-old-butcher. The patient underwent skin prick testing (SPT) with standard allergens (ALK) and different meat and spice extracts (Stallergènes), scratch-patch testing with spice mix containing glutamate, paprika and other spices. Specific serum-IgE was measured with CAP-FEIA. SPT only showed an immediate-type sensitization to mugwort (+ +), as well as different spices (paprika +, curry +, cumin +) and camomile (+ + +). Scratch-patch tests were negative for different meat, but strongly positive for spice mix (+ + +) after 30 min (wheal and flare) and (+ +) after 48 h (infiltration and vesiculation). Two healthy controls were tested negative for spice mix used from that patient (scratch-patch). Specific IgE was slightly elevated for paprika 0.47 kU/L (CAP class 1), anise 0.43 kU/L, curry 0.36 kU/L and mugwort 3.83 kU/L. Sx1 atopy-multiscreen was 3.8 kU/L due to a sensitization to mugwort alone. The tests performed demonstrate an IgE-mediated contact allergy to spices but also a delayed type allergy to spice mix as a manifestation of the mugwort-spice syndrome in this individual. When testing for occupational dermatitis in butchers, protein contact allergy to spices must also be taken into consideration.

  19. Polyhedral oligomeric silsesquioxane (POSS) polyimides as space-survivable materials

    NASA Astrophysics Data System (ADS)

    Tomczak, Sandra J.; Vij, Vandana; Marchant, Darrell; Minton, Timothy K.; Brunsvold, Amy L.; Wright, Michael E.; Petteys, Brian J.; Guenthner, Andrew J.; Yandek, Gregory R.; Mabry, Joe

    2006-09-01

    Polyimides (PIs) such as Kapton are used extensively in spacecraft thermal blankets, solar arrays, and space inflatable structures. Atomic oxygen (AO) in low Earth orbit (LEO) causes severe degradation of Kapton. SiO2 coatings impart remarkable oxidation resistance and have been widely used to protect Kapton, yet imperfections in the SiO2 application process and micrometeoroid/debris impact in orbit damage the SiO2 coating leading to Kapton erosion. A polyimide that is self-passivating by the formation of a silica layer upon exposure to AO has been achieved by the copolymerization of a polyhedral oligomeric silsesquioxane (POSS) diamine with the Kapton monomers, pyromellitic dianhydride and 4,4'-oxydianiline, resulting in POSS-Kapton-polyimide. The self-passivating properties have been shown by monitoring a 1 micron deep scratch in POSS-PIs after exposure to AO. Kapton H, SiO2-coated Kapton HN, and 8.75 weight % Si8O11 cage "main-chain" POSS-polyimide (8.75 wt % Si8O11 MC-POSS-PI) were exposed to equivalent AO fluences before and after being scratched. During the first AO exposure and outside of the scratch, these samples eroded 5.0 microns, 0 microns, and less than 200 nm respectively. During the second AO exposure, the samples eroded an additional 5.0 microns within the scratch and outside of the scratch, 7.0 microns within the scratch and 0 microns outside of the scratch, and 200 nm within the scratch and 0 microns outside of the scratch respectively. Surface analysis of MC-POSS-PI films exposed to a hyperthermal O-atom beam shows evidence for the formation of a SiO2 passivation layer upon AO exposure. This is exemplified by erosion yields of 3.5 and 7 wt % Si8O11 MC-POSS-PI samples which were 3.7 and 0.98 percent, respectively, of the erosion yield for Kapton H at a fluence of 8.5 x 1020 O atoms cm-2. Comparison of MC-POSS-PIs and "side-chain" POSS-PI (SC-POSS-PI) shows that these polymers have similar resistance to atomic oxygen and physical properties similar to Kapton H. Erosion yields and imaging of POSS-PIs flown on MISSE1, in a sample tray exposed to all elements (AO, UV light) of the space environment, demonstrated the greatly extended lifetime of POSS-PIs over polyimide.

  20. Bites and Scratches (For Parents)

    MedlinePlus

    ... pet (in kids, most animal bites are from dogs ) or a creature from the wild, scratches and ... First Aid: Animal Bites Cat Scratch Disease Preventing Dog Bites Rabies Cuts, Scratches, and Abrasions Dogs and ...

  1. A Novel Marking Reader for Progressive Addition Lenses Based on Gabor Holography.

    PubMed

    Perucho, Beatriz; Picazo-Bueno, José Angel; Micó, Vicente

    2016-05-01

    Progressive addition lenses (PALs) are marked with permanent engraved marks (PEMs) at standardized locations. Permanent engraved marks are very useful through the manufacturing and mounting processes, act as locator marks to re-ink the removable marks, and contain useful information about the PAL. However, PEMs are often faint and weak, obscured by scratches, partially occluded, and difficult to recognize on tinted lenses or with antireflection or scratch-resistant coatings. The aim of this article is to present a new generation of portable marking reader based on an extremely simplified concept for visualization and identification of PEMs in PALs. Permanent engraved marks on different PALs are visualized using classical Gabor holography as underlying principle. Gabor holography allows phase sample visualization with adjustable magnification and can be implemented in either classical or digital versions. Here, visual Gabor holography is used to provide a magnified defocused image of the PEMs onto a translucent visualization screen where the PEM is clearly identified. Different types of PALs (conventional, personalized, old and scratched, sunglasses, etc.) have been tested to visualize PEMs with the proposed marking reader. The PEMs are visible in every case, and variable magnification factor can be achieved simply moving up and down the PAL in the instrument. In addition, a second illumination wavelength is also tested, showing the applicability of this novel marking reader for different illuminations. A new concept of marking reader ophthalmic instrument has been presented and validated in the laboratory. The configuration involves only a commercial-grade laser diode and a visualization screen for PEM identification. The instrument is portable, economic, and easy to use, and it can be used for identifying patient's current PAL model and for marking removable PALs again or finding test points regardless of the age of the PAL, its scratches, tints, or coatings.

  2. Barriers and facilitators to cooking from 'scratch' using basic or raw ingredients: A qualitative interview study.

    PubMed

    Lavelle, Fiona; McGowan, Laura; Spence, Michelle; Caraher, Martin; Raats, Monique M; Hollywood, Lynsey; McDowell, Dawn; McCloat, Amanda; Mooney, Elaine; Dean, Moira

    2016-12-01

    Previous research has highlighted an ambiguity in understanding cooking related terminology and a number of barriers and facilitators to home meal preparation. However, meals prepared in the home still include convenience products (typically high in sugars, fats and sodium) which can have negative effects on health. Therefore, this study aimed to qualitatively explore: (1) how individuals define cooking from 'scratch', and (2) their barriers and facilitators to cooking with basic ingredients. 27 semi-structured interviews were conducted with participants (aged 18-58 years) living on the island of Ireland, eliciting definitions of 'cooking from scratch' and exploring the reasons participants cook in a particular way. The interviews were professionally transcribed verbatim and Nvivo 10 was used for an inductive thematic analysis. Our results highlighted that although cooking from 'scratch' lacks a single definition, participants viewed it as optimal cooking. Barriers to cooking with raw ingredients included: 1) time pressures; (2) desire to save money; (3) desire for effortless meals; (4) family food preferences; and (5) effect of kitchen disasters. Facilitators included: 1) desire to eat for health and well-being; (2) creative inspiration; (3) ability to plan and prepare meals ahead of time; and (4) greater self-efficacy in one's cooking ability. Our findings contribute to understanding how individuals define cooking from 'scratch', and barriers and facilitators to cooking with raw ingredients. Interventions should focus on practical sessions to increase cooking self-efficacy; highlight the importance of planning ahead and teach methods such as batch cooking and freezing to facilitate cooking from scratch. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Merry-Go-Round

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Dubbed 'Carousel,' the rock in this image was the target of the Mars Exploration Rover Opportunity science team's outcrop 'scuff test.' The image on the left, taken by the rover's navigation camera on sol 48 of the mission (March 12, 2004), shows the rock pre-scuff. On sol 51 (March 15, 2004), Opportunity slowly rotated its left front wheel on the rock, abrading it in the same way that geology students use a scratch test to determine the hardness of minerals. The image on the right, taken by the rover's navigation camera on sol 51, shows the rock post-scuff. In this image, it is apparent that Opportunity scratched the surface of 'Carousel' and deposited dirt that it was carrying in its wheel rims.

  4. The agar diffusion scratch assay - A novel method to assess the bioactive and cytotoxic potential of new materials and compounds

    PubMed Central

    Pusnik, Mascha; Imeri, Minire; Deppierraz, Grégoire; Bruinink, Arie; Zinn, Manfred

    2016-01-01

    A profound in vitro evaluation not only of the cytotoxic but also of bioactive potential of a given compound or material is crucial for predicting potential effects in the in vivo situation. However, most of the current methods have weaknesses in either the quantitative or qualitative assessment of cytotoxicity and/or bioactivity of the test compound. Here we describe a novel assay combining the ISO 10993-5 agar diffusion test and the scratch also termed wound healing assay. In contrast to these original tests this assay is able to detect and distinguish between cytotoxic, cell migration modifying and cytotoxic plus cell migration modifying compounds, and this at higher sensitivity and in a quantitative way. PMID:26861591

  5. Shared Components of Rhythm Generation for Locomotion and Scratching Exist Prior to Motoneurons

    PubMed Central

    Hao, Zhao-Zhe; Berkowitz, Ari

    2017-01-01

    Does the spinal cord use a single network to generate locomotor and scratching rhythms or two separate networks? Previous research showed that simultaneous swim and scratch stimulation (“dual stimulation”) in immobilized, spinal turtles evokes a single rhythm in hindlimb motor nerves with a frequency often greater than during swim stimulation alone or scratch stimulation alone. This suggests that the signals that trigger swimming and scratching converge and are integrated within the spinal cord. However, these results could not determine whether the integration occurs in motoneurons themselves or earlier, in spinal interneurons. Here, we recorded intracellularly from hindlimb motoneurons during dual stimulation. Motoneuron membrane potentials displayed regular oscillations at a higher frequency during dual stimulation than during swim or scratch stimulation alone. In contrast, arithmetic addition of the oscillations during swimming alone and scratching alone with various delays always generated irregular oscillations. Also, the standard deviation of the phase-normalized membrane potential during dual stimulation was similar to those during swimming or scratching alone. In contrast, the standard deviation was greater when pooling cycles of swimming alone and scratching alone for two of the three forms of scratching. This shows that dual stimulation generates a single rhythm prior to motoneurons. Thus, either swimming and scratching largely share a rhythm generator or the two rhythms are integrated into one rhythm by strong interactions among interneurons. PMID:28848402

  6. Thoracic osteomyelitis and epidural abscess formation due to cat scratch disease: case report.

    PubMed

    Dornbos, David; Morin, Jocelyn; Watson, Joshua R; Pindrik, Jonathan

    2016-12-01

    Osteomyelitis of the spine with associated spinal epidural abscess represents an uncommon entity in the pediatric population, requiring prompt evaluation and diagnosis to prevent neurological compromise. Cat scratch disease, caused by the pathogen Bartonella henselae, encompasses a wide spectrum of clinical presentations; however, an association with osteomyelitis and epidural abscess has been reported in only 4 other instances in the literature. The authors report a rare case of multifocal thoracic osteomyelitis with an epidural abscess in a patient with a biopsy-proven pathogen of cat scratch disease. A 5-year-old girl, who initially presented with vague constitutional symptoms, was diagnosed with cat scratch disease following biopsy of an inguinal lymph node. Despite appropriate antibiotics, she presented several weeks later with recurrent symptoms and back pain. Magnetic resonance imaging revealed 2 foci of osteomyelitis at T-8 and T-11 with an associated anterior epidural abscess from T-9 to T-12. Percutaneous image-guided vertebral biopsy revealed B. henselae by polymerase chain reaction analysis, and she was treated conservatively with doxycycline and rifampin with favorable clinical outcome.

  7. Fabrication mechanism of friction-induced selective etching on Si(100) surface

    PubMed Central

    2012-01-01

    As a maskless nanofabrication technique, friction-induced selective etching can easily produce nanopatterns on a Si(100) surface. Experimental results indicated that the height of the nanopatterns increased with the KOH etching time, while their width increased with the scratching load. It has also found that a contact pressure of 6.3 GPa is enough to fabricate a mask layer on the Si(100) surface. To understand the mechanism involved, the cross-sectional microstructure of a scratched area was examined, and the mask ability of the tip-disturbed silicon layer was studied. Transmission electron microscope observation and scanning Auger nanoprobe analysis suggested that the scratched area was covered by a thin superficial oxidation layer followed by a thick distorted (amorphous and deformed) layer in the subsurface. After the surface oxidation layer was removed by HF etching, the residual amorphous and deformed silicon layer on the scratched area can still serve as an etching mask in KOH solution. The results may help to develop a low-destructive, low-cost, and flexible nanofabrication technique suitable for machining of micro-mold and prototype fabrication in micro-systems. PMID:22356699

  8. Fabrication mechanism of friction-induced selective etching on Si(100) surface.

    PubMed

    Guo, Jian; Song, Chenfei; Li, Xiaoying; Yu, Bingjun; Dong, Hanshan; Qian, Linmao; Zhou, Zhongrong

    2012-02-23

    As a maskless nanofabrication technique, friction-induced selective etching can easily produce nanopatterns on a Si(100) surface. Experimental results indicated that the height of the nanopatterns increased with the KOH etching time, while their width increased with the scratching load. It has also found that a contact pressure of 6.3 GPa is enough to fabricate a mask layer on the Si(100) surface. To understand the mechanism involved, the cross-sectional microstructure of a scratched area was examined, and the mask ability of the tip-disturbed silicon layer was studied. Transmission electron microscope observation and scanning Auger nanoprobe analysis suggested that the scratched area was covered by a thin superficial oxidation layer followed by a thick distorted (amorphous and deformed) layer in the subsurface. After the surface oxidation layer was removed by HF etching, the residual amorphous and deformed silicon layer on the scratched area can still serve as an etching mask in KOH solution. The results may help to develop a low-destructive, low-cost, and flexible nanofabrication technique suitable for machining of micro-mold and prototype fabrication in micro-systems.

  9. High Rate Deposition of Thick CrN and Cr2N Coatings Using Modulated Pulse Power (MPP) Magnetron Sputtering

    DTIC Science & Technology

    2010-12-01

    in the conventional Bragg-Bentano mode. The residual stress of the coatings was measured by glancing incident angle XRD (GIXRD) in the same X - ray ...micro-analysis (EPMA), x - ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), nanoindentation, scratch test, and ball-on...the coatings was determined by XRD using a SIEMENS X - ray diffractometer (Model KRISTALLOFLEX-810) operated with K-alpha Cu radiation (30 kV and 20 mA

  10. Scratch Forensics

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

    Suratwala, T I; Miller, P E; Feit, M D

    2008-07-09

    Scratches on optical components which are formed during fabrication, cleaning, handling and end-use, are widespread and almost always detrimental. The impact of scratches on the end-use of the optic includes increased optical scatter, reduced system performance, and reduced strength. In the case of optics used in high intensity laser applications, prevention of scratches is paramount because they are closely associated with laser damage. Evaluation of the characteristics (dimensions, location on optic, shape, and orientation) of a scratch can serve a powerful tool to identify the cause of the scratch and lead to mitigations to prevent their reoccurrence. It is likelymore » that opticians have used such techniques for hundreds of years. In recent years, by applying techniques of fracture mechanics and tribology, several new semi-quantitative rules-of-thumb have been developed allowing one to estimate the size and shape of the scratch inducing asperity or rogue particle, the load on the particle, the depth of the fractures in the scratch, and properties of material housing the rogue particle. The following discussion reviews some these techniques, which as a whole, we refer to as 'Scratch Forsenics'.« less

  11. Mesenchymal stem cell-conditioned medium accelerates skin wound healing: An in vitro study of fibroblast and keratinocyte scratch assays

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

    Walter, M.N.M.; School of Life and Health Science, Aston University, Aston Triangle, Birmingham, B4 7EJ; Wright, K.T.

    2010-04-15

    We have used in vitro scratch assays to examine the relative contribution of dermal fibroblasts and keratinocytes in the wound repair process and to test the influence of mesenchymal stem cell (MSC) secreted factors on both skin cell types. Scratch assays were established using single cell and co-cultures of L929 fibroblasts and HaCaT keratinocytes, with wound closure monitored via time-lapse microscopy. Both in serum supplemented and serum free conditions, wound closure was faster in L929 fibroblast than HaCaT keratinocyte scratch assays, and in co-culture the L929 fibroblasts lead the way in closing the scratches. MSC-CM generated under serum free conditionsmore » significantly enhanced the wound closure rate of both skin cell types separately and in co-culture, whereas conditioned medium from L929 or HaCaT cultures had no significant effect. This enhancement of wound closure in the presence of MSC-CM was due to accelerated cell migration rather than increased cell proliferation. A number of wound healing mediators were identified in MSC-CM, including TGF-{beta}1, the chemokines IL-6, IL-8, MCP-1 and RANTES, and collagen type I, fibronectin, SPARC and IGFBP-7. This study suggests that the trophic activity of MSC may play a role in skin wound closure by affecting both dermal fibroblast and keratinocyte migration, along with a contribution to the formation of extracellular matrix.« less

  12. Mesenchymal stem cell-conditioned medium accelerates skin wound healing: an in vitro study of fibroblast and keratinocyte scratch assays.

    PubMed

    Walter, M N M; Wright, K T; Fuller, H R; MacNeil, S; Johnson, W E B

    2010-04-15

    We have used in vitro scratch assays to examine the relative contribution of dermal fibroblasts and keratinocytes in the wound repair process and to test the influence of mesenchymal stem cell (MSC) secreted factors on both skin cell types. Scratch assays were established using single cell and co-cultures of L929 fibroblasts and HaCaT keratinocytes, with wound closure monitored via time-lapse microscopy. Both in serum supplemented and serum free conditions, wound closure was faster in L929 fibroblast than HaCaT keratinocyte scratch assays, and in co-culture the L929 fibroblasts lead the way in closing the scratches. MSC-CM generated under serum free conditions significantly enhanced the wound closure rate of both skin cell types separately and in co-culture, whereas conditioned medium from L929 or HaCaT cultures had no significant effect. This enhancement of wound closure in the presence of MSC-CM was due to accelerated cell migration rather than increased cell proliferation. A number of wound healing mediators were identified in MSC-CM, including TGF-beta1, the chemokines IL-6, IL-8, MCP-1 and RANTES, and collagen type I, fibronectin, SPARC and IGFBP-7. This study suggests that the trophic activity of MSC may play a role in skin wound closure by affecting both dermal fibroblast and keratinocyte migration, along with a contribution to the formation of extracellular matrix. Copyright 2010 Elsevier Inc. All rights reserved.

  13. Pain and functional capacity in female fibromyalgia patients.

    PubMed

    Carbonell-Baeza, Ana; Aparicio, Virginia A; Sjöström, Michael; Ruiz, Jonatan R; Delgado-Fernández, Manuel

    2011-11-01

    To examine the association between pain and functional capacity levels. [corrected] Cross-sectional study. University of Granada. One hundred twenty-three women with fibromyalgia (51.7 ± 7.2 years). We measured weight and height, and body mass index (BMI) was calculated. We assessed tender points by pressure pain and functional capacity by means of the 30-second chair stand, handgrip strength, chair sit and reach, back scratch, blind flamingo, 8-ft up and go and 6-minute walk tests. We observed an association of tender points count with the chair stand and 6-minute walk tests (r = -0.273, P = 0.004 and r = -0.183, P = 0.046, respectively). These associations became nonsignificant once the analyses were adjusted by weight or BMI. We observed an association of algometer score with the back scratch, chair stand, and 6-minute walk tests (r = 0.238, P = 0.009; r = 0.363, P < 0.001; and r = 0.186, P = 0.043, respectively), which remained after adjusting for weight or BMI, except the association between algometer score and the 6-minute walk test that became nonsignificant once the analyses were adjusted by weight. Prevalence of overweight and obesity was 39.2 and 33.3%, respectively. There is an inverse association of tender points count with the chair stand and distance walked in the 6-minute walk tests, and a positive association of algometer score with the chair stand, distance walked in the 6-minute walk and back scratch tests, yet, weight status seems to play a role in these associations. Wiley Periodicals, Inc.

  14. Adhesion scratch testing - A round-robin experiment

    NASA Technical Reports Server (NTRS)

    Perry, A. J.; Valli, J.; Steinmann, P. A.

    1988-01-01

    Six sets of samples, TiN coated by chemical or physical vapor deposition methods (CVD or PVD) onto cemented carbide or high-speed steel (HSS), and TiC coated by CVD onto cemented carbide have been scratch tested using three types of commercially available scratch adhesion tester. With exception of one cemented carbide set, the reproducibility of the critical loads for any given set with a given stylus is excellent, about + or - 5 percent, and is about + or - 20 percent for different styli. Any differences in critical loads recorded for any given sample set can be attributed to the condition of the stylus (clean, new, etc.), the instrument used, the stylus itself (friction coefficient, etc.), and the sample set itself. One CVD set showed remarkably large differences in critical loads for different styli, which is thought to be related to a mechanical interaction between stylus and coating which is enhanced by a plastic deformability in the film related to the coating microstructure. The critical load for TiN on HSS increases with coating thickness, and differences in frictional conditions led to a systematic variation in the critical loads depending on the stylus used.

  15. A longitudinal dataset of five years of public activity in the Scratch online community.

    PubMed

    Hill, Benjamin Mako; Monroy-Hernández, Andrés

    2017-01-31

    Scratch is a programming environment and an online community where young people can create, share, learn, and communicate. In collaboration with the Scratch Team at MIT, we created a longitudinal dataset of public activity in the Scratch online community during its first five years (2007-2012). The dataset comprises 32 tables with information on more than 1 million Scratch users, nearly 2 million Scratch projects, more than 10 million comments, more than 30 million visits to Scratch projects, and more. To help researchers understand this dataset, and to establish the validity of the data, we also include the source code of every version of the software that operated the website, as well as the software used to generate this dataset. We believe this is the largest and most comprehensive downloadable dataset of youth programming artifacts and communication.

  16. A case-control analysis and laboratory study of the two feet-one hand syndrome in two dermatology hospitals in China.

    PubMed

    Zhan, P; Ge, Y P; Lu, X L; She, X D; Li, Z H; Liu, W D

    2010-07-01

    Two feet-one hand syndrome (bilateral plantar tinea pedis with coexistent unilateral tinea manuum) is commonly seen in dermatology clinics, but the cause of the unilateral hand involvement remains unresolved. To investigate the unilateral hand involvement in this syndrome. This was a case-control study. The experimental group comprised 113 patients with bilateral tinea pedis and unilateral tinea manuum and the control group comprised 44 patients with tinea pedis only, without tinea manuum. Clinical data were recorded and pathogens were identified by fungal examination. The predominant pathogen, Trichophyton rubrum, was genotyped by PCR amplification of tandem repeat elements from the ribosomal DNA nontranscribed spacer region. Scratching habits were significantly different between the groups, and there was a significant relationship between tinea manuum and the hand reportedly used to scratch the feet. In analysis of isolates from the feet and the involved hand, 94.5% of pairs were of the same species, and 80% of pairs had the same genotypes. Contact between hands and feet probably results in the transmission of dermatophytes from the feet to the scratching hand.

  17. Weak scratch detection and defect classification methods for a large-aperture optical element

    NASA Astrophysics Data System (ADS)

    Tao, Xian; Xu, De; Zhang, Zheng-Tao; Zhang, Feng; Liu, Xi-Long; Zhang, Da-Peng

    2017-03-01

    Surface defects on optics cause optic failure and heavy loss to the optical system. Therefore, surface defects on optics must be carefully inspected. This paper proposes a coarse-to-fine detection strategy of weak scratches in complicated dark-field images. First, all possible scratches are detected based on bionic vision. Then, each possible scratch is precisely positioned and connected to a complete scratch by the LSD and a priori knowledge. Finally, multiple scratches with various types can be detected in dark-field images. To classify defects and pollutants, a classification method based on GIST features is proposed. This paper uses many real dark-field images as experimental images. The results show that this method can detect multiple types of weak scratches in complex images and that the defects can be correctly distinguished with interference. This method satisfies the real-time and accurate detection requirements of surface defects.

  18. Programming by Choice: Urban Youth Learning Programming with Scratch

    ERIC Educational Resources Information Center

    Maloney, John; Peppler, Kylie; Kafai, Yasmin B.; Resnick, Mitchel; Rusk, Natalie

    2008-01-01

    This paper describes Scratch, a visual, block-based programming language designed to facilitate media manipulation for novice programmers. We report on the Scratch programming experiences of urban youth ages 8-18 at a Computer Clubhouse--an after school center--over an 18-month period. Our analyses of 536 Scratch projects collected during this…

  19. Learning Computer Science Concepts with Scratch

    ERIC Educational Resources Information Center

    Meerbaum-Salant, Orni; Armoni, Michal; Ben-Ari, Mordechai

    2013-01-01

    Scratch is a visual programming environment that is widely used by young people. We investigated if Scratch can be used to teach concepts of computer science (CS). We developed learning materials for middle-school students that were designed according to the constructionist philosophy of Scratch and evaluated them in a few schools during two…

  20. Mechanical properties of pulsed laser-deposited hydroxyapatite thin films implanted at high energy with N + and Ar + ions. Part II: nano-scratch tests with spherical tipped indenter

    NASA Astrophysics Data System (ADS)

    Pelletier, H.; Nelea, V.; Mille, P.; Muller, D.

    2004-02-01

    In this study we report a method to improve the adherence of hydroxyapatite (HA) thin films, using an ion beam implantation treatment. Crystalline HA films were grown by pulsed laser deposition technique (PLD), using an excimer KrF * laser. The films were deposited at room temperature in vacuum on Ti-5Al-2.5Fe alloy substrates previously coated with a ceramic TiN buffer layer and then annealed in ambient air at (500-600) °C. After deposition the films were implanted with N + and Ar + ions accelerated at high energy (1-1.5 MeV range) at a fixed dose of 10 16 cm -2. The intrinsic mechanical resistance and adherence to the TiN buffer layer of the implanted HA films have been evaluated by nano-scratch tests. We used for measurements a spherical indenter with a tip radius of 5 μm. Different scratch tests have been performed on implanted and unimplanted areas of films to put into evidence the effects of N + and Ar + ion implantation process on the films properties. Results show an enhancement of the dynamic mechanical properties in the implanted zones and influence of the nature of the implanted species. The best results are obtained for films implanted with nitrogen.

  1. The Effects of Shot and Laser Peening on Fatigue Life and Crack Growth in 2024 Aluminum Alloy and 4340 Steel

    NASA Technical Reports Server (NTRS)

    Everett, R. A., Jr.; Matthews, W. T.; Prabhakaran, R.; Newman, J. C., Jr.; Dubberly, M. J.

    2001-01-01

    Fatigue and crack growth tests have been conducted on 4340 steel and 2024-T3 aluminum alloy, respectively, to assess the effects of shot peening on fatigue life and the effects of shot and laser peening on crack growth. Two current programs involving fixed and rotary-wing aircraft will not be using shot peened structures. Since the shot peening compressive residual stress depth is usually less than the 0.05-inch initial damage tolerance crack size, it is believed by some that shot peening should have no beneficial effects toward retarding crack growth. In this study cracks were initiated from an electronic-discharged machining flaw which was cycled to produce a fatigue crack of approximately 0.05-inches in length and then the specimens were peened. Test results showed that after peening the crack growth rates were noticeably slower when the cracks were fairly short for both the shot and laser peened specimens resulting in a crack growth life that was a factor of 2 to 4 times greater than the results of the average unpeened test. Once the cracks reached a length of approximately 0.1-inches the growth rates were about the same for the peened and unpeened specimens. Fatigue tests on 4340 steel showed that the endurance limit of a test specimen with a 0.002-inch-deep machining-like scratch was reduced by approximately 40 percent. However, if the "scratched" specimen was shot peened after inserting the scratch, the fatigue life returned to almost 100 percent of the unflawed specimens original fatigue life.

  2. Computer-aided analysis of cutting processes for brittle materials

    NASA Astrophysics Data System (ADS)

    Ogorodnikov, A. I.; Tikhonov, I. N.

    2017-12-01

    This paper is focused on 3D computer simulation of cutting processes for brittle materials and silicon wafers. Computer-aided analysis of wafer scribing and dicing is carried out with the use of the ANSYS CAE (computer-aided engineering) software, and a parametric model of the processes is created by means of the internal ANSYS APDL programming language. Different types of tool tip geometry are analyzed to obtain internal stresses, such as a four-sided pyramid with an included angle of 120° and a tool inclination angle to the normal axis of 15°. The quality of the workpieces after cutting is studied by optical microscopy to verify the FE (finite-element) model. The disruption of the material structure during scribing occurs near the scratch and propagates into the wafer or over its surface at a short range. The deformation area along the scratch looks like a ragged band, but the stress width is rather low. The theory of cutting brittle semiconductor and optical materials is developed on the basis of the advanced theory of metal turning. The fall of stress intensity along the normal on the way from the tip point to the scribe line can be predicted using the developed theory and with the verified FE model. The crystal quality and dimensions of defects are determined by the mechanics of scratching, which depends on the shape of the diamond tip, the scratching direction, the velocity of the cutting tool and applied force loads. The disunity is a rate-sensitive process, and it depends on the cutting thickness. The application of numerical techniques, such as FE analysis, to cutting problems enhances understanding and promotes the further development of existing machining technologies.

  3. Lessons Learned from Teaching Scratch as an Introduction to Object-Oriented Programming in Delphi

    ERIC Educational Resources Information Center

    van Zyl, Sukie; Mentz, Elsa; Havenga, Marietjie

    2016-01-01

    As part of curriculum changes in South Africa, an introductory programming language, Scratch, must first be taught before switching to the well-established teaching of Delphi. The nature of programming in Scratch is considerably different from that in Delphi. It was assumed that the teaching of Scratch as introductory programming language could…

  4. Effects of Using Alice and Scratch in an Introductory Programming Course for Corrective Instruction

    ERIC Educational Resources Information Center

    Chang, Chih-Kai

    2014-01-01

    Scratch, a visual programming language, was used in many studies in computer science education. Most of them reported positive results by integrating Scratch into K-12 computer courses. However, the object-oriented concept, one of the important computational thinking skills, is not represented well in Scratch. Alice, another visual programming…

  5. Reliability and feasibility of physical fitness tests in female fibromyalgia patients.

    PubMed

    Carbonell-Baeza, A; Álvarez-Gallardo, I C; Segura-Jiménez, V; Castro-Piñero, J; Ruiz, J R; Delgado-Fernández, M; Aparicio, V A

    2015-02-01

    The aim of the present study was to determine the reliability and feasibility of physical fitness tests in female fibromyalgia patients. 100 female fibromyalgia patients (aged 50.6±8.6 years) performed the following tests twice (7 days interval test-retest): chair sit and reach, back scratch, handgrip strength, arm curl, chair stand, 8 feet up and go, and 6-min walk. Significant differences between test and retest were found in the arm curl (mean difference: 1.25±2.16 repetitions, Cohen d=0.251), chair stand (0.99±1.7 repetitions, Cohen d=0.254) and 8 feet up and go (-0.38±1.09 s, Cohen d=0.111) tests. Intraclass correlation coefficients (ICC) range from 0.92 in the arm curl test to 0.96 in the back scratch test. The feasibility of the tests (patients able to complete the test) ranged from 89% in the arm curl test to 100% in the handgrip strength test. Therefore, the reliability and feasibility of the physical fitness tests examined is acceptable for female fibromyalgia patients. © Georg Thieme Verlag KG Stuttgart · New York.

  6. Characterization of calcium phosphate coatings deposited by Nd:YAG laser ablation at 355 nm: influence of thickness.

    PubMed

    Fernández-Pradas, J M; Clèries, L; Sardin, G; Morenza, J L

    2002-05-01

    Calcium phosphate coatings were deposited by pulsed laser ablation with a radiation of 355 nm from a Nd:YAG laser. All the coatings were obtained at the same conditions, but deposition was stopped after different number of pulses to get coatings with different thickness. The influence of thickness in the structural and mechanical properties of the coatings was investigated. Coatings structure was characterised by scanning electron microscopy, grazing incidence X-ray diffractometry and Raman spectroscopy. The mechanical properties were evaluated by scratch test. The morphology of the coatings is dominated by the presence of droplets. The coatings are composed mainly of hydroxyapatite, alpha tricalcium phosphate and amorphous calcium phosphate. Thinner coatings withstand higher loads of failure in the scratch test.

  7. Sonography of cat scratch disease.

    PubMed

    Melville, David M; Jacobson, Jon A; Downie, Brian; Biermann, J Sybil; Kim, Sung Moon; Yablon, Corrie M

    2015-03-01

    To characterize the sonographic features of cat scratch disease and to identify features that allow differentiation from other causes of medial epitrochlear masses. After Institutional Review Board approval was obtained, patients who underwent sonography for a medial epitrochlear mass or lymph node were identified via the radiology information system. Patients were divided into 2 groups: cat scratch disease and non-cat scratch disease, based on pathologic results and clinical information. Sonograms were retrospectively reviewed and characterized with respect to dimension, shape (round, oval, or lobular), symmetry, location (subcutaneous or intramuscular), multiplicity, echogenicity (anechoic, hypoechoic, isoechoic, hyperechoic, or mixed), hyperechoic hilum (present or absent), adjacent anechoic or hypoechoic area, hyperemia (present or absent), pattern of hyperemia if present (central, peripheral, or mixed), increased posterior through-transmission (present or absent), and shadowing (present or absent). Sonographic findings were compared between the patients with and without cat scratch disease. The final patient group consisted of 5 cases of cat scratch disease and 16 cases of other causes of medial epitrochlear masses. The 2 sonographic findings that were significantly different between the cat scratch disease and non-cat scratch disease cases included mass asymmetry (P = .0062) and the presence of a hyperechoic hilum (P = .0075). The other sonographic findings showed no significant differences between the groups. The sonographic finding of an epitrochlear mass due to cat scratch disease most commonly is that of a hypoechoic lobular or oval mass with central hyperemia and a possible adjacent fluid collection; however, the presence of asymmetry and a hyperechoic hilum differentiate cat scratch disease from other etiologies. © 2015 by the American Institute of Ultrasound in Medicine.

  8. A hip joint simulator study using new and physiologically scratched femoral heads with ultra-high molecular weight polyethylene acetabular cups.

    PubMed

    Barbour, P S; Stone, M H; Fisher, J

    2000-01-01

    This study validates a hip joint simulator configuration as compared with other machines and clinical wear rates using smooth metal and ceramic femoral heads and ultra-high molecular weight polyethylene (UHMWPE) acetabular cups. Secondly the wear rate of UHMWPE cups is measured in the simulator with deliberately scratched cobalt-chrome heads to represent the type of mild and severe scratch damage found on retrieved heads. Finally, the scratching processes are described and the resulting scratches compared with those found in retrieved cobalt-chrome heads. For smooth cobalt-chrome and zirconia heads the wear rates were found to be statistically similar to other simulator machines and within the normal range found from clinical studies. An increased wear rate was found with cobalt-chrome heads scratched using either the diamond stylus or the bead cobalt-chrome but the greatest increase was with the diamond scratched heads which generated scratches of similar dimensions to those on retrieved heads. A greater than twofold increase in wear rate is reported for these heads when compared with smooth heads. This increased wear rate is, however, still within the limits of data from clinical wear studies.

  9. [Bartonella henselae, an ubiquitous agent of proteiform zoonotic disease].

    PubMed

    Edouard, S; Raoult, D

    2010-06-01

    Bartonella henselae is the causative agent of cat scratch disease, a human infection usually characterized by persistent regional lymphadenopathy. It is transmitted to humans by cat scratches or bites. Cats are the major reservoir for this bacterium thus B. henselae has a worldwide distribution. The bacterial pathogenicity may bay emphasized by the immune status of the infected host. Angiomatosis or hepatic peliosis are the most frequent clinical manifestations in immunocompromised patients. B. henselae is also responsible for endocarditis in patients with valvular diseases, and may induce various clinical presentations such as: bacteriemia, retinitis, musculoskeletal disorders, hepatic or splenic diseases, encephalitis, or myocarditis. Several diagnostic tools are available; they may be combined and adapted to every clinical setting. B. henselae is a fastidious bacterium; its diagnosis is mainly made by PCR and blood tests. No treatment is required for the benign form of cat scratch disease. For more severe clinical presentations, the treatment must be adapted to every clinical presentation.

  10. Evidence that displacement activities facilitate behavioural transitions in ring-tailed lemurs.

    PubMed

    Buckley, Victoria; Semple, Stuart

    2012-07-01

    Displacement activities are behavioural patterns defined by their apparent irrelevance to an animal's ongoing actions. Despite being identified in diverse taxa, their function remains poorly understood. One hypothesis posits that displacement activities facilitate transitions between different behaviours by mediating changes in animals' motivational state. Under this hypothesis, it is predicted that displacement activities will occur more frequently around changes in behaviour than at other times, and also that rates of displacement activities will be higher before than after such behavioural transitions. We tested these two predictions in wild ring-tailed lemurs (Lemur catta). During focal observations, animals' behavioural state was continuously recorded, as were all occurrences of self-scratching, a common displacement activity in this species. Self-scratching rates were found to be significantly elevated both before and after behavioural transitions. Furthermore, self-scratching rates were significantly higher before behavioural transitions occurred than after. These results, therefore, provide support for the hypothesis that displacement activities facilitate behavioural transitions in L. catta. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Effect of powder reactivity on fabrication and properties of NiAl/Al2O3 composite coated on cast iron using spark plasma sintering

    NASA Astrophysics Data System (ADS)

    Beyhaghi, Maryam; Kiani-Rashid, Ali-Reza; Kashefi, Mehrdad; Khaki, Jalil Vahdati; Jonsson, Stefan

    2015-07-01

    Powder mixtures of Ni, NiO and Al are ball milled for 1 and 10 h. X-ray diffractometry and differential thermal analysis show that while ball milling for 1 h produced mechanically activated powder; 10 h ball milling produced NiAl and Al2O3 phases. Dense NiAl/Al2O3 composite coatings are formed on gray cast iron substrate by spark plasma sintering (SPS) technique. The effect of powder reactivity on microstructure, hardness and scratch hardness of NiAl/Al2O3 coatings after SPS is discussed. Results show that in the coating sample made of mechanically activated powder in situ synthesis of NiAl/Al2O3 composite coating is fulfilled and a thicker well-formed diffusion bond layer at the interface between coating and substrate is observed. The diffusion of elements across the bond layers and phase evolution in the bond layers were investigated. No pores or cracks were observed at the interface between coating layer and substrate in any of samples. Higher Vickers hardness and scratch hardness values in coating made of 10 h ball milled powder than in coating fabricated from 1 h ball milled powder are attributed to better dispersion of Al2O3 reinforcement particles in NiAl matrix and nano-crystalline structure of NiAl matrix. Scratched surface of coatings did not reveal any cracking or spallation at coating-substrate interface indicating their good adherence at test conditions.

  12. Involvement of the BLT2 receptor in the itch-associated scratching induced by 12-(S)-lipoxygenase products in ICR mice

    PubMed Central

    Kim, H J; Kim, D K; Kim, H; Koh, J Y; Kim, K M; Noh, M S; Lee, S; Kim, S; Park, S H; Kim, J J; Kim, S Y; Lee, C H

    2008-01-01

    Background and purpose: Recently, we reported that 12(S)-HPETE (12(S)-hydroperoxyeicosa-5Z,8Z,10E,14Z-tetraenoic acid) induces scratching in ICR mice. We hypothesized that 12(S)-HPETE might act as an agonist of the low-affinity leukotriene B4 receptor BLT2. To confirm the involvement of the BLT2 receptor in 12(S)-HPETE-induced scratching, we studied the scratch response using the BLT2 receptor agonists compound A (4′-{[pentanoyl (phenyl) amino]methyl}-1,1′-biphenyl-2-carboxylic acid) and 12(S)-HETE (12(S)-hydroxyeicosa-5Z,8Z,10E,14Z-tetraenoic acid). Experimental approach: A video recording was used to determine whether the BLT2 receptor agonists caused itch-associated scratching in ICR mice. Selective antagonists and several chemicals were used. Key results: Both 12(S)-HETE and compound A dose dependently induced scratching in the ICR mice. The dose–response curve for compound A showed peaks at around 0.005–0.015 nmol per site. Compound A- and 12(S)-HETE-induced scratching was suppressed by capsaicin and naltrexon. We examined the suppressive effects of U75302 (6-[6-(3-hydroxy-1E,5Z-undecadienyl)-2-pyridinyl]-1,5-hexanediol, the BLT1 receptor antagonist) and LY255283 (1-[5-ethyl-2-hydroxy-4-[[6-methyl-6-(1H-tetrazol-5-yl)heptyl]oxy]phenyl]-ethanone, the BLT2 receptor antagonist) on the BLT2 agonist-induced scratching. LY255283 suppressed compound A- and 12(S)-HETE-induced scratching, but U75302 did not. LY255283 required a higher dose to suppress the compound A-induced scratching than it did to suppress the 12(S)-HETE-induced scratching. One of the BLT2 receptor agonists, 12(R)-HETE (12(R)-hydroxyeicosa-5Z,8Z,10E,14Z-tetraenoic acid), also induced scratching in the ICR mice. Conclusions and implications: Our present results corroborate the hypothesis that the BLT2 receptor is involved in 12(S)-lipoxygenase-product-induced scratching in ICR mice. We also confirmed that this animal model could be a valuable means of evaluating the effects of BLT2 receptor antagonists. PMID:18536755

  13. The impact of gape on the performance of the skull in chisel-tooth digging and scratch digging mole-rats (Rodentia: Bathyergidae).

    PubMed

    McIntosh, Andrew F; Cox, Philip G

    2016-10-01

    The African mole-rats (Bathyergidae) are a family of rodents highly adapted for life underground. Previous research has shown that chisel-tooth digging mole-rats (which use their incisors to dig burrows) are clearly distinguishable from scratch diggers (which only use the forelimbs to tunnel) on the basis of morphology of the skull, and that the differences are linked to the production of high bite forces and wide gapes. We hypothesized that the skull of a chisel-tooth digging mole-rat would perform better at wider gapes than that of a scratch digging mole-rat during incisor biting. To test this hypothesis, we created finite-element models of the cranium of the scratch digging Bathyergus suillus and the chisel-tooth digging Fukomys mechowii , and loaded them to simulate incisor bites at different gapes. Muscle loads were scaled such that the ratio of force to surface area was the same in both models. We measured three performance variables: overall stress across the cranium, mechanical efficiency of biting and degree of deformation across the skull. The Fukomys model had a more efficient incisor bite at all gapes, despite having greater average stress across the skull. In addition, the Fukomys model deformed less at wider gapes, whereas the Bathyergus model deformed less at narrower gapes. These properties of the cranial morphology of Fukomys and Bathyergus are congruent with their respective chisel-tooth and scratch digging behaviours and, all other factors being equal, would enable the more efficient production of bite force at wider gapes in Fukomys . However, in vivo measurements of muscle forces and activation patterns are needed to fully understand the complex biomechanics of tooth digging.

  14. The impact of gape on the performance of the skull in chisel-tooth digging and scratch digging mole-rats (Rodentia: Bathyergidae)

    NASA Astrophysics Data System (ADS)

    McIntosh, Andrew F.; Cox, Philip G.

    2016-10-01

    The African mole-rats (Bathyergidae) are a family of rodents highly adapted for life underground. Previous research has shown that chisel-tooth digging mole-rats (which use their incisors to dig burrows) are clearly distinguishable from scratch diggers (which only use the forelimbs to tunnel) on the basis of morphology of the skull, and that the differences are linked to the production of high bite forces and wide gapes. We hypothesized that the skull of a chisel-tooth digging mole-rat would perform better at wider gapes than that of a scratch digging mole-rat during incisor biting. To test this hypothesis, we created finite-element models of the cranium of the scratch digging Bathyergus suillus and the chisel-tooth digging Fukomys mechowii, and loaded them to simulate incisor bites at different gapes. Muscle loads were scaled such that the ratio of force to surface area was the same in both models. We measured three performance variables: overall stress across the cranium, mechanical efficiency of biting and degree of deformation across the skull. The Fukomys model had a more efficient incisor bite at all gapes, despite having greater average stress across the skull. In addition, the Fukomys model deformed less at wider gapes, whereas the Bathyergus model deformed less at narrower gapes. These properties of the cranial morphology of Fukomys and Bathyergus are congruent with their respective chisel-tooth and scratch digging behaviours and, all other factors being equal, would enable the more efficient production of bite force at wider gapes in Fukomys. However, in vivo measurements of muscle forces and activation patterns are needed to fully understand the complex biomechanics of tooth digging.

  15. Rapid changes in substance P signaling and neutral endopeptidase induced by skin-scratching stimulation in mice.

    PubMed

    Yamaoka, Junichi; Kawana, Seiji

    2007-11-01

    Skin-scratching is a commonly seen behavior in patients with pruritus which sometimes exacerbates original lesions. Substance P (SP) signaling may play a predominant role in the pathophysiology induced by skin-scratching, however, it has not been well-elucidated. To clarify changes in SP, its receptor NK-1R and a degradating enzyme neutral endopeptidase (NEP) induced by skin-scratching stimulation in mice. After skin-scratching stimulation was given to mice, changes in SP signaling were investigated as follows. Mast cell degranulation was examined with toluidine blue staining. SP-immunoreactive nerve fibers and the expressions of NK-1R and NEP were examined with immunofluorescence. Protein contents of SP and the enzymatic activity of NEP were examined with an ELISA and a colorimetric assay, respectively. After skin-scratching stimulation, mast cells significantly degranulated within several minutes. SP-immunoreactive nerve fibers disappeared immediately from sensory nerve fibers, indicating the quick secretion and the depletion of SP. Both protein contents of SP and NEP activity in skin decreased dramatically soon after skin-scratching stimulation and thereafter they returned to the basal level within a week. The expression of NK-1R was significantly upregulated in epidermal basal keratinocytes after several days, in which NEP and NK-1R were well-coexpressed. Blocking NK-1R by an NK-1R antagonist suppressed scratching-induced decreases in SP-immunoreactive nerve fibers and in NEP activity. The present study clarified changing patterns of factors involved in SP signaling and NEP induced by skin-scratching stimulation. These findings provide basic and useful information to understand the pathophysiology of scratching-associated pruritic skin diseases.

  16. Cat scratch disease

    MedlinePlus

    ... t scratch and bite. Don't allow a cat to lick your skin, eyes, mouth, or open wounds or scratches. Use flea control measures to lower the risk your cat develops the disease. Don't touch feral cats. ...

  17. Control of surface thermal scratch of strip in tandem cold rolling

    NASA Astrophysics Data System (ADS)

    Chen, Jinshan; Li, Changsheng

    2014-07-01

    The thermal scratch seriously affects the surface quality of the cold rolled stainless steel strip. Some researchers have carried out qualitative and theoretical studies in this field. However, there is currently a lack of research on effective forecast and control of thermal scratch defects in practical production, especially in tandem cold rolling. In order to establish precise mathematical model of oil film thickness in deformation zone, the lubrication in cold rolling process of SUS410L stainless steel strip is studied, and major factors affecting oil film thickness are also analyzed. According to the principle of statistics, mathematical model of critical oil film thickness in deformation zone for thermal scratch is built, with fitting and regression analytical method, and then based on temperature comparison method, the criterion for deciding thermal scratch defects is put forward. Storing and calling data through SQL Server 2010, a software on thermal scratch defects control is developed through Microsoft Visual Studio 2008 by MFC technique for stainless steel in tandem cold rolling, and then it is put into practical production. Statistics indicate that the hit rate of thermal scratch is as high as 92.38%, and the occurrence rate of thermal scratch is decreased by 89.13%. Owing to the application of the software, the rolling speed is increased by approximately 9.3%. The software developed provides an effective solution to the problem of thermal scratch defects in tandem cold rolling, and helps to promote products surface quality of stainless steel strips in practical production.

  18. Atomistic insights on the nanoscale single grain scratching mechanism of silicon carbide ceramic based on molecular dynamics simulation

    NASA Astrophysics Data System (ADS)

    Liu, Yao; Li, Beizhi; Kong, Lingfei

    2018-03-01

    The precision and crack-free surface of brittle silicon carbide (SiC) ceramic was achieved in the nanoscale ductile grinding. However, the nanoscale scratching mechanism and the root causes of SiC ductile response, especially in the atomistic aspects, have not been fully understood yet. In this study, the SiC atomistic scale scratching mechanism was investigated by single diamond grain scratching simulation based on molecular dynamics. The results indicated that the ductile scratching process of SiC could be achieved in the nanoscale depth of cut through the phase transition to an amorphous structure with few hexagonal diamond structure. Furthermore, the silicon atoms in SiC could penetrate into diamond grain which may cause wear of diamond grain. It was further found out that the chip material in the front of grain flowed along the grain side surface to form the groove protrusion as the scratching speed increases. The higher scratching speed promoted more atoms to transfer into the amorphous structure and reduced the hexagonal diamond and dislocation atoms number, which resulted in higher temperature, smaller scratching force, smaller normal stress, and thinner subsurface damage thickness, due to larger speed impaction causing more bonds broken which makes the SiC more ductile.

  19. Nobiletin and tangeretin ameliorate scratching behavior in mice by inhibiting the action of histamine and the activation of NF-κB, AP-1 and p38.

    PubMed

    Jang, Se-Eun; Ryu, Kwon-Ryeol; Park, Sung-Hwan; Chung, Suna; Teruya, Yuto; Han, Myung Joo; Woo, Je-Tae; Kim, Dong-Hyun

    2013-11-01

    Nobiletin and tangeretin are polymethoxy flavonoids that are abundantly present in the pericarp of Citrus unshiu (family Rutaceae) and the fruit of Citrus depressa (family Rutaceae). They exhibit various biological activities, including anti-inflammatory and anti-asthmatic effects. To evaluate the anti-allergic effects of nobiletin and tangeretin, we measured their inhibitory effects in histamine- or compound 48/80-induced scratching behavioral mice. Nobiletin and tangeretin potently inhibited scratching behavior, as well as histamine-induced vascular permeability. Furthermore, they inhibited the expression of the allergic cytokines, IL-4 and TNF-α as well as the activation of their transcription factors NF-κB, AP-1 and p38 in histamine-stimulated skin tissues. They also inhibited the expression of IL-4 and TNF-α and the activation of NF-κB and c-jun in PMA-stimulated RBL-2H3 cells. Furthermore, nobiletin and tangeretin inhibited protein kinase C (PKC) activity and the IgE-induced degranulation of RBL-2H3 cells. These agents showed potent anti-histamine effect through the Magnus test when guinea pig ileum was used. Based on these results, nobiletin and tangeretin may ameliorate scratching behavioral reactions by inhibiting the action of histamine as well as the activation of the transcription factors NF-κB and AP-1 via PKC. © 2013.

  20. 7 CFR 201.58a - Indistinguishable seeds.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... hydroxide may cause eye irritation. (2) Preparation of seeds: To insure imbibition, scratch, prick, or... may be used. Remove and place the dry seed coat from seeds into individual test tubes or suitable...

  1. Isolated mediastinal necrotizing granulomatous lymphadenopathy due to cat-scratch disease.

    PubMed

    Lovis, A; Clerc, O; Lazor, R; Jaton, K; Greub, G

    2014-02-01

    We report a patient suffering from cat-scratch disease limited to mediastinal lymphadenitis. Although rare, cat-scratch disease should be considered in the differential diagnosis of mediastinal lymphadenitis, especially when patients were exposed to cats.

  2. Cat scratch disease presenting as acute mastoiditis.

    PubMed

    Cheung, Veronique Wan Fook; Moxham, J Paul

    2010-01-01

    To present the first published case of Cat Scratch Disease presenting as acute mastoiditis and review the relevant literature to discuss the Otolaryngologic manifestations of this disease and its treatment. A case report and literature review of the Otolaryngologic manifestations of Cat Scratch Disease. A case report of a clinical scenario followed by a standard literature review. PubMed, EMBASE, and Cochrane database were used to find articles related to the Otolaryngologic manifestations of Cat Scratch Disease. A 6 year-old female presented to the Otolaryngologist with the typical appearance of acute mastoiditis. CT Scan confirmed breakdown of the osseous septae of the mastoid and mastoidectomy was undertaken. Granulation tissue and infected lymph nodes adjacent to the mastoid cortex were positive for Cat Scratch Disease. The patient was treated expectantly and recovered uneventfully. This is the first literature report of Cat Scratch Disease presenting as an acute mastoiditis.

  3. Transmitters and pathways mediating inhibition of spinal itch-signaling neurons by scratching and other counterstimuli.

    PubMed

    Akiyama, Tasuku; Iodi Carstens, Mirela; Carstens, Earl

    2011-01-01

    Scratching relieves itch, but the underlying neural mechanisms are poorly understood. We presently investigated a role for the inhibitory neurotransmitters GABA and glycine in scratch-evoked inhibition of spinal itch-signaling neurons in a mouse model of chronic dry skin itch. Superficial dorsal horn neurons ipsilateral to hindpaw dry skin treatment exhibited a high level of spontaneous firing that was significantly attenuated by cutaneous scratching, pinch and noxious heat. Scratch-evoked inhibition was nearly abolished by spinal delivery of the glycine antagonist, strychnine, and was markedly attenuated by respective GABA(A) and GABA(B) antagonists bicuculline and saclofen. Scratch-evoked inhibition was also significantly attenuated (but not abolished) by interruption of the upper cervical spinal cord, indicating the involvement of both segmental and suprasegmental circuits that engage glycine- and GABA-mediated inhibition of spinal itch-signaling neurons by noxious counterstimuli.

  4. Defect scriber

    DOEpatents

    Russell, Harold C.

    1979-01-01

    This disclosure describes a device for repeatably scribing a V-shaped scratch having sharply defined dimensions on the interior surface of a nuclear reactor fuel rod tube. A cutting tool having a V-shaped cutting tip is supported within the fuel rod tube so that the V-shaped cutting tip can be pivoted about an axis and scribe a scratch on the interior surface of the fuel rod tube. Lengthwise the scratch runs parallel to a line drawn through the axis of the fuel rod tube and is in the shape of an arc, and widthwise the scratch is V-shaped. This shape is used because the dimensions of the scratch can be plugged into appropriate formulas to calculate stress intensity of cracks in fuel rod tubes. Since the fuel rod tubes which are to be scribed may be radioactive, the scratching assembly is designed for use in a fixture which allows it to be operated in a cave by remote control handling devices.

  5. Withdrawal of repeated morphine enhances histamine-induced scratching responses in mice.

    PubMed

    Abe, Kenji; Kobayashi, Kanayo; Yoshino, Saori; Taguchi, Kyoji; Nojima, Hiroshi

    2015-04-01

    An itch is experientially well known that the scratching response of conditions such as atopic dermatitis is enhanced under psychological stress. Morphine is typical narcotic drug that induces a scratching response upon local application as an adverse drug reaction. Although long-term treatment with morphine will cause tolerance and dependence, morphine withdrawal can cause psychologically and physiologically stressful changes in humans. In this study, we evaluated the effects of morphine withdrawal on histamine-induced scratching behavior in mice. Administration of morphine with progressively increasing doses (10-50 mg/kg, i.p.) was performed for 5 consecutive days. At 3, 24, 48, and 72 hr after spontaneous withdrawal from the final morphine dose, histamine was intradermally injected into the rostral part of the back and then the number of bouts of scratching in 60 min was recorded and summed. We found that at 24 hr after morphine withdrawal there was a significant increase in histamine-induced scratching behavior. The spinal c-Fos positive cells were also significantly increased. The relative adrenal weight increased and the relative thymus weight decreased, both significantly. Moreover, the plasma corticosterone levels changed in parallel with the number of scratching bouts. These results suggest that morphine withdrawal induces a stressed state and enhances in histamine-induced scratching behavior. Increased reaction against histamine in the cervical vertebrae will participate in this stress-induced itch enhancement.

  6. The associations between physical fitness and cardiometabolic risk and body-size phenotypes in perimenopausal women.

    PubMed

    Gregorio-Arenas, E; Ruiz-Cabello, P; Camiletti-Moirón, D; Moratalla-Cecilia, N; Aranda, P; López-Jurado, M; Llopis, J; Aparicio, V A

    2016-10-01

    To study the association between physical fitness and body-size phenotypes, and to test which aspects of physical fitness show the greatest independent association with cardiometabolic risk in perimenopausal women. This cross-sectional study involved 228 women aged 53±5years from southern Spain. Physical fitness was assessed by means of the Senior Fitness Test Battery (additionally including handgrip strength and timed up-and-go tests). Anthropometry, resting heart rate, blood pressure and plasma markers of lipid, glycaemic and inflammatory status were measured by standard procedures. The harmonized definition of the 'metabolically healthy but obese' (MHO) phenotype was employed to classify individuals. The overall prevalence of the MHO phenotype was 13% but was 43% among the obese women. Apart from traditional markers, metabolically healthy non-obese women had lower levels of C-reactive protein than women with the other phenotypes (p<0.001), and levels of glycosylated haemoglobin were lower in MHO women than in metabolically abnormal non-obese women (overall p=0.004). Most of the components of physical fitness differed with body-size phenotypes. The 6-min walk and the back-scratch tests presented the most robust differences (both p<0.001). Moreover, the women's performance on the back-scratch (β=0.32; p<0.001) and the 6-min walk (β=0.22; p=0.003) tests was independently associated with the clustered cardiometabolic risk. The back-scratch test explained 10% of the variability (step 1, p<0.001), and the final model, which also included the 6-min walk test (step 2, p=0.003), explained 14% of the variability. Low upper-body flexibility was the most important fitness indicator of cardiometabolic risk in perimenopausal women, but cardiorespiratory fitness also played an important role. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. A novel approach of high speed scratching on silicon wafers at nanoscale depths of cut

    PubMed Central

    Zhang, Zhenyu; Guo, Dongming; Wang, Bo; Kang, Renke; Zhang, Bi

    2015-01-01

    In this study, a novel approach of high speed scratching is carried out on silicon (Si) wafers at nanoscale depths of cut to investigate the fundamental mechanisms in wafering of solar cells. The scratching is conducted on a Si wafer of 150 mm diameter with an ultraprecision grinder at a speed of 8.4 to 15 m/s. Single-point diamonds of a tip radius of 174, 324, and 786 nm, respectively, are used in the study. The study finds that at the onset of chip formation, an amorphous layer is formed at the topmost of the residual scratch, followed by the pristine crystalline lattice beneath. This is different from the previous findings in low speed scratching and high speed grinding, in which there is an amorphous layer at the top and a damaged layer underneath. The final width and depth of the residual scratch at the onset of chip formation measured vary from 288 to 316 nm, and from 49 to 62 nm, respectively. High pressure phases are absent from the scratch at the onset of either chip or crack formation. PMID:26548771

  8. Using Robinhood to Manage Files on Peregrine | High-Performance Computing |

    Science.gov Websites

    : $ module load robinhood Here are some usage examples: To find all the files on /projects that you own scratch.conf -u $USER /scratch File purging on /scratch uses last access time to determine which files are

  9. Urine-marking and ground-scratching by free-ranging Arctic Wolves, Canis lupus arctos, in summer

    USGS Publications Warehouse

    Mech, L.D.

    2006-01-01

    Urine-marking and ground-scratching were observed in an Arctic Wolf (Canis lupus) pack on Ellesmere Island, Nunavut, Canada, during 16 summers between 1986 and 2005. All previously known urination postures and ground-scratching by breeding males and females were seen, and incidence of marking and scratching was greatest when non-pack wolves were present. Observations of urine-marking of food remains supported the conclusion from a captive Wolf study that such marking signals lack of edible food.

  10. Itch-associated scratching contributes to the development of dermatitis and hyperimmunoglobulinaemia E in NC/Nga mice.

    PubMed

    Hashimoto, Yuki; Takaoka, Akiko; Sugimoto, Masanori; Honma, Yusuke; Sakurai, Takanobu; Futaki, Nobuko; Arai, Iwao

    2011-10-01

    Atopic dermatitis (AD) is related to immunoglobulin E (IgE) production, and a type-1 and type-2 helper T cell (Th1/Th2) imbalance has been hypothesized as the aetiology. While itching and scratching are important factors in the development of dermatitis, the mechanisms underlying these phenomena are poorly understood. We investigated the relationship between scratching, transepidermal water loss (TEWL), signs of dermatitis and serum Ig levels in NC/Nga mice, a model of AD. We also sensitized specific pathogen-free (SPF)-NC/Nga mice and BALB/c mice to mite antigen to determine the effects of IgE overproduction on scratching and investigated the involvement of mast cells and T/B cells in the induction of scratching using WBB6F1-W/W(v) mice and C.B.17/Icr-scid mice. Under conventional conditions, the scratch counts increased, followed by increases in TEWL and the inflammation score in NC/Nga mice that were not kept under SPF conditions. However, no change was observed in scratching, TEWL, or signs of dermatitis in mite antigen-sensitized SPF-NC/Nga and BALB/c mice, although the serum total IgE, IgG(1) and IgG(2a) levels increased. The scratch count increased significantly in both the WBB6F1-W/W(v) mice and C.B.17/Icr-scid mice when they were co-housed with skin-lesioned NC/Nga mice, raised under conventional conditions. These results show that IgE overproduction results from itch-associated scratching-induced dermatitis in NC/Nga mice. © 2011 John Wiley & Sons A/S.

  11. Detection and Length Estimation of Linear Scratch on Solid Surfaces Using an Angle Constrained Ant Colony Technique

    NASA Astrophysics Data System (ADS)

    Pal, Siddharth; Basak, Aniruddha; Das, Swagatam

    In many manufacturing areas the detection of surface defects is one of the most important processes in quality control. Currently in order to detect small scratches on solid surfaces most of the industries working on material manufacturing rely on visual inspection primarily. In this article we propose a hybrid computational intelligence technique to automatically detect a linear scratch from a solid surface and estimate its length (in pixel unit) simultaneously. The approach is based on a swarm intelligence algorithm called Ant Colony Optimization (ACO) and image preprocessing with Wiener and Sobel filters as well as the Canny edge detector. The ACO algorithm is mostly used to compensate for the broken parts of the scratch. Our experimental results confirm that the proposed technique can be used for detecting scratches from noisy and degraded images, even when it is very difficult for conventional image processing to distinguish the scratch area from its background.

  12. Cat-scratch uveitis confirmed by histological, serological, and molecular diagnoses.

    PubMed

    Font, Ramon L; Del Valle, Maria; Mitchell, Bradley M; Boniuk, Milton

    2011-04-01

    To report a case of a cat-scratch uveitis caused by Bartonella henselae, which was confirmed by histology, serology, and polymerase chain reaction (PCR) methodology. An iris nodule was biopsied from a 4-year-old child who was scratched by a kitten on the side of his face and developed redness of the eye associated with cervical lymphadenopathy. Sections of the iridectomy specimen were stained with hematoxylin-eosin, periodic acid-Schiff, and Warthin-Starry technique for histopathologic evaluation. Additionally, serologic tests and molecular diagnosis using B. henselae-specific PCR were performed. Histopathologically, sections of the iridectomy specimen showed a zonal granulomatous inflammation with a central iris necrotic abscess surrounded by a mantle of epithelioid histiocytes and more peripherally by lymphocytes and plasma cells. The Warthin-Starry stain disclosed scattered short bacilli within the necrotic abscess morphologically compatible with B. henselae. Report of serologic tests for B. henselae disclosed a negative immunoglobulin G antibody (negative: less than 12) and a positive immunoglobulin M antibody of 18 (positive: greater than 15). Other serologic studies including Toxocara, histoplasmin, blastomycin, coccidioidin, aspergillin, and Chlamydia were all negative. PCR was positive for B. henselae DNA. Our case showed a unilateral chronic granulomatous iritis with the histopathologic features compatible with CSD caused by B. henselae bacillus as demonstrated in the iris biopsy and confirmed by serology and PCR technique. This case is an example of a relatively rare uveal manifestation of CSD.

  13. 77 FR 36948 - Airworthiness Directives; Bombardier, Inc. Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-20

    ... lower pins for gouges, scratches, and corrosion, and replacing if necessary; and adding serial numbers..., scratches, and corrosion of the HSTA attachment pins and trunnions, which could result in failure of these... and lower pins for gouges, scratches, and corrosion, and replacing if necessary; and adding serial...

  14. The effect of propofol on intrathecal morphine-induced pruritus and its mechanism.

    PubMed

    Liu, Xiulan; Zhang, Jing; Zhao, Hongyan; Mei, Hongxia; Lian, Qingquan; Shangguan, Wangning

    2014-02-01

    Previous studies have shown that a low dose of propofol IV bolus had a beneficial effect on intrathecal morphine-induced pruritus in humans. However, its exact mechanism has not been fully understood. In this study, we hypothesized that propofol relieved intrathecal morphine-induced pruritus in rats by upregulating the expression of cannabinoid-1 (CB[1]) receptors in anterior cingulate cortex (ACC). Twenty-four Sprague-Dawley rats were divided into a control group and 20, 40, 80 μg/kg morphine groups to create an intrathecal morphine-induced scratching model. The effects of propofol on intrathecal 40 μg/kg morphine-induced scratching responses were then evaluated. Sixty rats were randomly assigned to control, normal saline, intralipid, and propofol groups, with pruritus behavior observation or killed 8 minutes after venous injection of normal saline, intralipid, or propofol, and brain tissues were then collected for assay. Immunohistochemistry was then performed to identify the expression of CB (1) receptor in ACC, and the concentration of CB(1) receptor in ACC was determined by Western blot analysis. Compared with the control group, rats in the 20, 40, 80 μg/kg morphine groups had higher mean scratching response rates after intrathecal morphine injection (P =0.020, 0.005, and 0.002, respectively). There was a statistical difference between 20 and 40 μg/kg morphine groups at 10 to 15 and 15 to 20 timepoints after intrathecal morphine injection (P = 0.049 and 0.017, respectively). Propofol almost abolished the scratching response that was induced by 40 μg/kg intrathecal morphine injection (F[2, 15] = 46.87, P < 0.001; F[22, 165] = 2.37, P = 0.001). Compared with the intralipid and normal saline groups, the scratching behavior was significantly attenuated in the propofol group (P < 0.001). Compared with control, normal saline, and intralipid groups, the protein expression of CB(1) receptor in ACC (Western blot) in the propofol group increased (0.86 ± 0.21, 0.94 ± 0.18, 0.86 ± 0.13, and 1.34 ± 0.32, respectively, P < 0.001). There was no significant difference among control, normal saline, and intralipid groups. Compared with the control, normal saline, and intralipid groups, the average number of neurons of CB(1) receptor in the ACC area were higher in the propofol group (21.0 ± 1.4, 19.3 ± 1.8, 24.8 ± 7.7, and 37.2 ± 3.3, respectively, P < 0.001). Morphine elicits dose-independent scratching responses after intrathecal injection in rats. Morphine 40 μg/kg intrathecal injection-induced scratching responses can be prevented by propofol. Increased protein expression of CB(1) receptors in ACC may contribute to the reversal of intrathecal morphine-induced scratching.

  15. Using Scratch: An Integrated Problem-Solving Approach to Mathematical Thinking

    ERIC Educational Resources Information Center

    Calder, Nigel

    2010-01-01

    "Scratch" is a media-rich digital environment that utilises a building block command structure to manipulate graphic, audio, and video aspects. It incorporates elements of Logo including "tinkerability" in the programming process. In "Scratch" students use geometric and measurement concepts such as coordinates, angle, and length measurements. It…

  16. 78 FR 7647 - Airworthiness Directives; Bombardier, Inc. Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-04

    ... gouges, scratches, and corrosion, and replacing the trunnions if necessary; and adding serial numbers and... section. We are issuing this AD to detect and correct cracking, gouges, scratches, and corrosion of the... trunnions and upper and lower pins for gouges, scratches, and corrosion, and replacing if necessary; and...

  17. The Scratch Programming Language and Environment

    ERIC Educational Resources Information Center

    Maloney, John; Resnick, Mitchel; Rusk, Natalie; Silverman, Brian; Eastmond, Evelyn

    2010-01-01

    Scratch is a visual programming environment that allows users (primarily ages 8 to 16) to learn computer programming while working on personally meaningful projects such as animated stories and games. A key design goal of Scratch is to support self-directed learning through tinkering and collaboration with peers. This article explores how the…

  18. Maternal serum but not breast milk IL-5, IL-6, and IL-13 immune markers are associated with scratching among infants.

    PubMed

    Soto-Ramírez, Nelís; Boyd, Keith; Zhang, Hongmei; Gangur, Venugopal; Goetzl, Laura; Karmaus, Wilfried

    2016-01-01

    Scratching in infants is considered to be related to early development of eczema. Little is known about the effects of maternal immune markers on scratching among infants. The objective is to compare the risks related to maternal serum immune markers (IMs) during pregnancy and IMs in breast milk for the occurrence of scratching in infants at 6 and 12 months of age. Pregnant women were recruited in Columbia and Charleston, South Carolina. Blood (median 3 weeks prepartum) and breast milk (3 weeks postpartum) samples were collected. The concentrations of interferon (IFN)-γ, IFN gamma-induced protein 10 (IP-10) (or CXCL10), CCL11, interleukin (IL) 1β, IL-4, IL-5, IL-6, IL-8 (CXCL8), IL-10, IL-12 (p70), IL-13, transforming growth factor (TGF)-β1, and immunoglobulin (Ig) A in both maternal serum and whey were assayed using optimized immunoassays. Scratching and skin manifestations were ascertained at 6 and 12 months. Generalized estimating equations were used to estimate relative risks (RRs) of IMs for repeated measurements of scratching, considering intra-individual correlations and adjusting for confounders. Of 178 women, 161 provided blood and 115 breast milk samples. IL-1β, IL-4, IL-10, IL-12, and CCL11 in maternal serum and whey were not analyzed due to a large proportion of non-detectable values. Infants in the highest tertile of IL-6 and IL-13 in maternal serum were at higher risk of scratching (RR 1.73 and 1.84, respectively; p ≤ 0.002) compared to infants in the first tertile; similarly, infants born to mothers with high (versus low) levels of serum IL-5 were also at increased risk (RR 1.60, p = 0.002). None of the breast milk IMs studied were associated with scratching. Scratching but not doctors diagnosed eczema was associated with higher levels of maternal IL-5, IL-6, and IL-13 during pregnancy. Further investigations are necessary to determine how maternal serum IMs influence infants scratching.

  19. Surface property modification of silicon

    NASA Technical Reports Server (NTRS)

    Danyluk, S.

    1984-01-01

    The main emphasis of this work has been to determine the wear rate of silicon in fluid environments and the parameters that influence wear. Three tests were carried out on single crystal Czochralski silicon wafers: circular and linear multiple-scratch tests in fluids by a pyramidal diamond simulated fixed-particle abrasion; microhardness and three-point bend tests were used to determine the hardness and fracture toughness of abraded silicon and the extent of damage induced by abrasion. The wear rate of (100) and (111) n and p-type single crystal Cz silicon abraded by a pyramidal diamond in ethanol, methanol, acetone and de-ionized water was determined by measuring the cross-sectional areas of grooves of the circular and linear multiple-scratch tests. The wear rate depends on the loads on the diamond and is highest for ethanol and lowest for de-ionized water. The surface morphology of the grooves showed lateral and median cracks as well as a plastically deformed region. The hardness and fracture toughness are critical parameters that influence the wear rate. Microhardness tests were conducted to determine the hardness as influenced by fluids. Median cracks and the damage zone surrounding the indentations were also related to the fluid properties.

  20. Preservice Teachers' Introduction to Computing: Exploring Utilization of Scratch

    ERIC Educational Resources Information Center

    Cetin, Ibrahim

    2016-01-01

    Computational thinking has been gaining new impetus in the academic community and in K-12 level education. Scratch is a visual programming environment that can be utilized to teach and learn introductory computing concepts. There are some studies investigating the effectiveness of Scratch for K-12 level education. However, studies that have been…

  1. Peripheral NMDA Receptor/NO System Blockage Inhibits Itch Responses Induced by Chloroquine in Mice

    PubMed Central

    Haddadi, Nazgol-Sadat; Foroutan, Arash; Ostadhadi, Sattar; Azimi, Ehsan; Rahimi, Nastaran; Nateghpour, Mehdi; Lerner, Ethan A.; Dehpour, Ahmad Reza

    2017-01-01

    Intradermal administration of chloroquine (CQ) provokes scratching behavior in mice. Chloroquine-induced itch is histamine-independent and we have reported that the nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) pathway is involved in CQ-induced scratching behavior in mice. Previous studies have demonstrated that activation of N-methyl-d-aspartate receptors (NMDARs) induces NO production. Here we show that NMDAR antagonists significantly decrease CQ-induced scratching in mice while a non-effective dose of an NMDAR agonist potentiates the scratching behavior provoked by sub-effective doses of CQ. In contrast, combined pre-treatment with sub-effective doses of an NMDAR antagonist, MK-801, and the NO synthase inhibitor, L-N-nitro arginine methyl ester (L-NAME), decreases CQ-induced scratching behavior. While intradermal administration of CQ significantly increases the concentration of intradermal nitrite, the end product of NO metabolism, effective doses of intraperitoneal and intradermal MK-801 significantly decrease intradermal nitrite levels. Likewise, administration of an effective dose of L-NAME significantly decreases CQ-induced nitrite production. We conclude that the NMDA/NO pathway in the skin modulates CQ-induced scratching behavior. PMID:28119997

  2. An unusual outcome in a child with hepatosplenic cat-scratch disease.

    PubMed

    Vukelić, Dalibor; Benić, Branka; Bozinović, Dragomir; Vuković, Branka; Dakovic Rode, Oktavija; Culig, Zdravka; Vuković, Jurica; Batinica, Stipe; Visnjić, Stjepan; Puljiz, Ivan

    2006-10-01

    Typical cat-scratch disease (Bartonella henselae infection) in an immunocompetent child is usually associated with a history of scratch, bite or intimate contact with a cat. Most patients develop a non-tender papule in the scratch line after three to ten days. This may persist for only a few days or as long as two to three weeks. During the next two weeks or more, regional lymph nodes that drain the area gradually enlarge and then slowly resolve in more than 10% of patients. The nodes develop overlying erythema and may suppurate. Atypical forms of cat-scratch disease occur in a minority of cases and are characterized by ocular or neurological manifestations, hepatosplenic involvement, vertebral osteomyelitis, endocarditis etc. Immunocompromised individuals with B. henselae infection may develop bacillary angiomatosis, bacillary peliosis, and relapsing bacteremia. There have been several reports of hepatosplenic granulomas caused by B. henselae in immunocompetent children. We report a case of a 6-year-old boy with the hepatosplenic form of cat-scratch disease. Despite early diagnosis and long-term antimicrobial treatment, splenectomy could not be avoided.

  3. The Active Participation of ASLAA in the SMA Project (I)

    NASA Astrophysics Data System (ADS)

    Yuan, Chi

    This is a progress report of the project that our institute is actively engaged. The two 6m sub-millimeter telescopes are constructed in Taiwan. The antennas, which has been constructed to Aeronautic Research Laboratory, are taken good shapes. The back structures are completed and passed stress test analysis. The mounts are also finished. We expect both will be completed, put together, and tested in late 1999. We have started a receiver lab from scratch. Now, it has completed the assembly of the first SMA receiver and in the process of doing all the tests. Our receiver lab has also made its first Nb-AlO3-Nb junction of 230 Ghz. We hope to make our telescopes to be the number 3 and 4 of the SMA to be placed at Mauna Kea next year.

  4. Identification and Development of Simple Acceptance Tests for MRE Film Pouch Materials

    DTIC Science & Technology

    2006-01-26

    retort applications, such as wheat snack bread, shortbread cookies, and beef jerky. Film #2 (48 GA PET/10#PE/.00035F/2 mil sealant) was chosen as the...for polymers) is the melt flow direction and its relation to the direction of the scratch test. It is known that, when polymers are molded or extruded

  5. Scratch2 prevents cell cycle re-entry by repressing miR-25 in postmitotic primary neurons.

    PubMed

    Rodríguez-Aznar, Eva; Barrallo-Gimeno, Alejandro; Nieto, M Angela

    2013-03-20

    During the development of the nervous system the regulation of cell cycle, differentiation, and survival is tightly interlinked. Newly generated neurons must keep cell cycle components under strict control, as cell cycle re-entry leads to neuronal degeneration and death. However, despite their relevance, the mechanisms controlling this process remain largely unexplored. Here we show that Scratch2 is involved in the control of the cell cycle in neurons in the developing spinal cord of the zebrafish embryo. scratch2 knockdown induces postmitotic neurons to re-enter mitosis. Scratch2 prevents cell cycle re-entry by maintaining high levels of the cycle inhibitor p57 through the downregulation of miR-25. Thus, Scratch2 appears to safeguard the homeostasis of postmitotic primary neurons by preventing cell cycle re-entry.

  6. Endometrial scratching in women with implantation failure after a first IVF/ICSI cycle; does it lead to a higher live birth rate? The SCRaTCH study: a randomized controlled trial (NTR 5342).

    PubMed

    van Hoogenhuijze, N E; Torrance, H L; Mol, F; Laven, J S E; Scheenjes, E; Traas, M A F; Janssen, C; Cohlen, B; Teklenburg, G; de Bruin, J P; van Oppenraaij, R; Maas, J W M; Moll, E; Fleischer, K; van Hooff, M H; de Koning, C; Cantineau, A; Lambalk, C B; Verberg, M; Nijs, M; Manger, A P; van Rumste, M; van der Voet, L F; Preys-Bosman, A; Visser, J; Brinkhuis, E; den Hartog, J E; Sluijmer, A; Jansen, F W; Hermes, W; Bandell, M L; Pelinck, M J; van Disseldorp, J; van Wely, M; Smeenk, J; Pieterse, Q D; Boxmeer, J C; Groenewoud, E R; Eijkemans, M J C; Kasius, J C; Broekmans, F J M

    2017-07-21

    Success rates of assisted reproductive techniques (ART) are approximately 30%, with the most important limiting factor being embryo implantation. Mechanical endometrial injury, also called 'scratching', has been proposed to positively affect the chance of implantation after embryo transfer, but the currently available evidence is not yet conclusive. The primary aim of this study is to determine the effect of endometrial scratching prior to a second fresh in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycle on live birth rates in women with a failed first IVF/ICSI cycle. Multicenter randomized controlled trial in Dutch academic and non-academic hospitals. A total of 900 women will be included of whom half will undergo an endometrial scratch in the luteal phase of the cycle prior to controlled ovarian hyperstimulation using an endometrial biopsy catheter. The primary endpoint is the live birth rate after the 2 nd fresh IVF/ICSI cycle. Secondary endpoints are costs, cumulative live birth rate (after the full 2 nd IVF/ICSI cycle and over 12 months of follow-up); clinical and ongoing pregnancy rate; multiple pregnancy rate; miscarriage rate and endometrial tissue parameters associated with implantation failure. Multiple studies have been performed to investigate the effect of endometrial scratching on live birth rates in women undergoing IVF/ICSI cycles. Due to heterogeneity in both the method and population being scratched, it remains unclear which group of women will benefit from the procedure. The SCRaTCH trial proposed here aims to investigate the effect of endometrial scratching prior to controlled ovarian hyperstimulation in a large group of women undergoing a second IVF/ICSI cycle. NTR 5342 , registered July 31 st , 2015. Version 4.10, January 4th, 2017.

  7. [Behavior therapy technics in the treatment of endogenous eczema with special reference to compulsive scratching].

    PubMed

    Böddeker, K W; Böddeker, M

    1976-01-01

    An exact observation and description of scratching behavior leads to a behavioral model for the obsessional scratching in patients with atopic dermatitis. The patient who cannot handle negative emotions because of a deficit in social behavior strategies suffers from diffuse tension. He can reduce the tension for the moment by scratching. Thus itching is being reinforced. The feeling of misbehavior occurs with delay and then again can serve as a stimulus for more tension.--Basing on this model behavior therapeutical techniques for breaking up this vicious circle are discussed.

  8. Combining wet etching and real-time damage event imaging to reveal the most dangerous laser damage initiator in fused silica.

    PubMed

    Hu, Guohang; Zhao, Yuanan; Liu, Xiaofeng; Li, Dawei; Xiao, Qiling; Yi, Kui; Shao, Jianda

    2013-08-01

    A reliable method, combining a wet etch process and real-time damage event imaging during a raster scan laser damage test, has been developed to directly determine the most dangerous precursor inducing low-density laser damage at 355 nm in fused silica. It is revealed that ~16% of laser damage sites were initiated at the place of the scratches, ~49% initiated at the digs, and ~35% initiated at invisible defects. The morphologies of dangerous scratches and digs were compared with those of moderate ones. It is found that local sharp variation at the edge, twist, or inside of a subsurface defect is the most dangerous laser damage precursor.

  9. Effects of Annotations and Homework on Learning Achievement: An Empirical Study of Scratch Programming Pedagogy

    ERIC Educational Resources Information Center

    Su, Addison Y. S.; Huang, Chester S. J.; Yang, Stephen J. H.; Ding, T. J.; Hsieh, Y. Z.

    2015-01-01

    In Taiwan elementary schools, Scratch programming has been taught for more than four years. Previous studies have shown that personal annotations is a useful learning method that improve learning performance. An annotation-based Scratch programming (ASP) system provides for the creation, share, and review of annotations and homework solutions in…

  10. Comparing Students' Scratch Skills with Their Computational Thinking Skills in Terms of Different Variables

    ERIC Educational Resources Information Center

    Oluk, Ali; Korkmaz, Özgen

    2016-01-01

    This study aimed to compare 5th graders' scores obtained from Scratch projects developed in the framework of Information Technologies and Software classes via Dr Scratch web tool with the scores obtained from Computational Thinking Levels Scale and to examine this comparison in terms of different variables. Correlational research model was…

  11. Advanced Mitigation Process (AMP) for Improving Laser Damage Threshold of Fused Silica Optics

    NASA Astrophysics Data System (ADS)

    Ye, Xin; Huang, Jin; Liu, Hongjie; Geng, Feng; Sun, Laixi; Jiang, Xiaodong; Wu, Weidong; Qiao, Liang; Zu, Xiaotao; Zheng, Wanguo

    2016-08-01

    The laser damage precursors in subsurface of fused silica (e.g. photosensitive impurities, scratches and redeposited silica compounds) were mitigated by mineral acid leaching and HF etching with multi-frequency ultrasonic agitation, respectively. The comparison of scratches morphology after static etching and high-frequency ultrasonic agitation etching was devoted in our case. And comparison of laser induce damage resistance of scratched and non-scratched fused silica surfaces after HF etching with high-frequency ultrasonic agitation were also investigated in this study. The global laser induce damage resistance was increased significantly after the laser damage precursors were mitigated in this case. The redeposition of reaction produce was avoided by involving multi-frequency ultrasonic and chemical leaching process. These methods made the increase of laser damage threshold more stable. In addition, there is no scratch related damage initiations found on the samples which were treated by Advanced Mitigation Process.

  12. Bone scintigraphy in children with cat scratch disease.

    PubMed

    Donoso, Gilda; Paulsen, Cesar; Riquelme, Paulina; Lobo, Gabriel; Gutierrez, Daniela; Perez, Andrés; Jiménez, César

    2013-12-01

    The objective of this study was to evaluate the degree and incidence of bone involvement in patients with cat scratch disease. Patients admitted between 2004 and 2011 at the pediatric department for cat scratch disease and a positive serology for Bartonella henselae were identified. Only those having undergone a bone scintigraphy (BS) were included in this retrospective study. Sixteen girls and 8 boys with a mean age of 7 years were studied. Bone scintigraphy was positive in 6 (25%), but only 2 had bone pain. Axial involvement was present in all 6 patients, and appendicular lesions in 3 of them. Three patients had a BS control, with improvement or normalization after treatment with antibiotics. Bone involvement occurs infrequently in patients with cat scratch disease and is not always associated with specific signs. Cat scratch disease must be suspected in patients with fever of unknown origin presenting multifocal lesions on BS.

  13. Anti-scratching behavioral effect of the essential oil and phytol isolated from Artemisia princeps Pamp. in mice.

    PubMed

    Ryu, Kwon-Ryeol; Choi, Jong-Youl; Chung, Suna; Kim, Dong-Hyun

    2011-01-01

    The anti-scratching behavioral effect of the essential oil and phytol isolated from Artemisia princeps Pamp. (AP, family Asteraceae), which is widely used in traditional medicine for inflammatory diseases, was investigated IN VIVO. Treatment of mice with AP essential oil (APEO) and phytol inhibited histamine- and compound 48/80-induced scratching behaviors. The anti-scratching behavioral effects of APEO and phytol are in proportion to their vascular permeability-inhibitory effects. These agents also inhibited the level of allergic cytokines, IL-4, and TNF- α, and the activation of transcription factors, NF- κB and c-jun (AP-1), in histamine-treated skin tissues. Based on these results, APEO and phytol may improve scratching behavior in skin by inhibiting the expression of allergic cytokines via the regulation of NF- κB and AP-1 activation. © Georg Thieme Verlag KG Stuttgart · New York.

  14. Advanced Mitigation Process (AMP) for Improving Laser Damage Threshold of Fused Silica Optics

    PubMed Central

    Ye, Xin; Huang, Jin; Liu, Hongjie; Geng, Feng; Sun, Laixi; Jiang, Xiaodong; Wu, Weidong; Qiao, Liang; Zu, Xiaotao; Zheng, Wanguo

    2016-01-01

    The laser damage precursors in subsurface of fused silica (e.g. photosensitive impurities, scratches and redeposited silica compounds) were mitigated by mineral acid leaching and HF etching with multi-frequency ultrasonic agitation, respectively. The comparison of scratches morphology after static etching and high-frequency ultrasonic agitation etching was devoted in our case. And comparison of laser induce damage resistance of scratched and non-scratched fused silica surfaces after HF etching with high-frequency ultrasonic agitation were also investigated in this study. The global laser induce damage resistance was increased significantly after the laser damage precursors were mitigated in this case. The redeposition of reaction produce was avoided by involving multi-frequency ultrasonic and chemical leaching process. These methods made the increase of laser damage threshold more stable. In addition, there is no scratch related damage initiations found on the samples which were treated by Advanced Mitigation Process. PMID:27484188

  15. Surface Damage Mechanism of Monocrystalline Si Under Mechanical Loading

    NASA Astrophysics Data System (ADS)

    Zhao, Qingliang; Zhang, Quanli; To, Suet; Guo, Bing

    2017-03-01

    Single-point diamond scratching and nanoindentation on monocrystalline silicon wafer were performed to investigate the surface damage mechanism of Si under the contact loading. The results showed that three typical stages of material removal appeared during dynamic scratching, and a chemical reaction of Si with the diamond indenter and oxygen occurred under the high temperature. In addition, the Raman spectra of the various points in the scratching groove indicated that the Si-I to β-Sn structure (Si-II) and the following β-Sn structure (Si-II) to amorphous Si transformation appeared under the rapid loading/unloading condition of the diamond grit, and the volume change induced by the phase transformation resulted in a critical depth (ductile-brittle transition) of cut (˜60 nm ± 15 nm) much lower than the theoretical calculated results (˜387 nm). Moreover, it also led to abnormal load-displacement curves in the nanoindentation tests, resulting in the appearance of elbow and pop-out effects (˜270 nm at 20 s, 50 mN), which were highly dependent on the loading/unloading conditions. In summary, phase transformation of Si promoted surface deformation and fracture under both static and dynamic mechanical loading.

  16. Improved self-healing of polyethylene/carbon black nanocomposites by their shape memory effect.

    PubMed

    Wang, Xiaoyan; Zhao, Jun; Chen, Min; Ma, Lan; Zhao, Xiaodong; Dang, Zhi-Min; Wang, Zhenwen

    2013-02-07

    In this work, the improved self-healing of cross-linked polyethylene (PE) (cPE)/carbon black (CB) nanocomposites by their shape memory effect (SME) is investigated. CB nanoparticles are found to be homogeneously dispersed in the PE matrix and significantly increase the strength of the materials. Compared with the breaking of linear PE (lPE) at the melting temperature (T(m)), the cPE and cPE/CB nanocomposites still have high strength above T(m) due to the formation of networks. The cPE and cPE/CB nanocomposites show both high strain fixity ratio (R(f)) and high strain recovery ratio (R(r)). Crystallization-induced elongation is observed for all the prepared shape memory polymer (SMP) materials and the effect becomes less remarkable with increasing volume fraction of CB nanoparticles (v(CB)). The scratch self-healing tests show that the cross-linking of PE matrix, the addition of CB nanoparticles, and the previous stretching in the direction perpendicular to the scratch favor the closure of the scratch and its complete healing. This SME-aided self-healing could have potential applications in diverse fields such as coating and structure materials.

  17. Adhesion Strength of TiN Coatings at Various Ion Etching Deposited on Tool Steels Using Cathodic Arc Pvd Technique

    NASA Astrophysics Data System (ADS)

    Ali, Mubarak; Hamzah, Esah; Ali, Nouman

    Titanium nitride (TiN) widely used as hard coating material was coated on tool steels, namely on high-speed steel (HSS) and D2 tool steel by physical vapor deposition method. The goal of this study was to examine the effect of ion etching with and without titanium (Ti) and chromium (Cr) on the adhesion strength of TiN coatings deposited on tool steels. From the scratch tester, it was observed that by increasing Ti ion etching showed an increase in adhesion strength of the deposited coatings. The coatings deposited with Cr ion etching showed poor adhesion compared with the coatings deposited with Ti ion etching. Scratch test measurements showed that the coating deposited with titanium ion etching for 16 min is the most stable coating and maintained even at the critical load of 66 N. The curve obtained via penetration depth along the scratch trace is linear in the case of HSS, whereas is slightly flexible in the case of D2 tool steel. The coatings deposited on HSS exhibit better adhesion compared with those on D2 tool steel.

  18. Strategies for Analyzing Tone Languages

    ERIC Educational Resources Information Center

    Coupe, Alexander R.

    2014-01-01

    This paper outlines a method of auditory and acoustic analysis for determining the tonemes of a language starting from scratch, drawing on the author's experience of recording and analyzing tone languages of north-east India. The methodology is applied to a preliminary analysis of tone in the Thang dialect of Khiamniungan, a virtually undocumented…

  19. CO 2-induced chemo-mechanical alteration in reservoir rocks assessed via batch reaction experiments and scratch testing

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

    Aman, Michael; Espinoza, D. Nicolas; Ilgen, Anastasia G.

    Here, the injection of carbon dioxide (CO 2) into geological formations results in a chemical re-equilibration between the mineral assemblage and the pore fluid, with ensuing mineral dissolution and re-precipitation. Hence, target rock formations may exhibit changes of mechanical and petrophysical properties due to CO 2 exposure. We conducted batch reaction experiments with Entrada Sandstone and Summerville Siltstone exposed to de-ionized water and synthetic brine under reservoir pressure (9–10 MPa) and temperature (80°C) for up to four weeks. Samples originate from the Crystal Geyser field site, where a naturally occurring CO 2 seepage alters portions of these geologic formations. Wemore » conducted micro-scratch tests on rock samples without alteration, altered under laboratory conditions, and naturally altered over geologic time. Scratch toughness and hardness decrease as a function of exposure time and water salinity up to 52% in the case of Entrada and 87% in the case of Summerville after CO 2-induced alteration in the laboratory. Imaging of altered cores with SEM-EDS and X-ray microCT methods show dissolution of carbonate and silica cements and matrix accompanied by minor dissolution of Fe-oxides, clays, and other silicates. Parallel experiments using powdered samples confirm that dissolution of carbonate and silica are the primary reactions. The batch reaction experiments in the autoclave utilize a high fluid to rock volume ratio and represent an end member of possible alteration associated with CO 2 storage systems. These types of tests serve as a pre-screening tool to identify the susceptibility of rock facies to CO 2-related chemical-mechanical alteration during long-term CO 2 storage.« less

  20. Effects of a multicomponent exercise program in institutionalized elders with Alzheimer's disease.

    PubMed

    Sampaio, Arnaldina; Marques, Elisa A; Mota, Jorge; Carvalho, Joana

    2016-10-18

    This study examined the effect of a Multicomponent Training (MT) intervention on cognitive function, functional fitness and anthropometric variables in institutionalized patients with Alzheimer's disease (AD). Thirty-seven institutionalized elders (84.05 ± 5.58 years) clinically diagnosed with AD (mild and moderate stages) were divided into two groups: Experimental Group (EG, n = 19) and Control Group (CG, n = 18). The EG participated in a six-month supervised MT program (aerobic, muscular resistance, flexibility and postural exercises) of 45-55 minutes/session, twice/week. Cognitive function (MMSE), physical fitness (Senior Fitness Test) and anthropometric variables (Body Mass Index and Waist Circumference), were assessed before (M1), after three months (M2) and after six months (M3) of the experimental protocol. A two-way ANOVA, with repeated measures, revealed significant group and time interactions on cognitive function, chair stand, arm curl, 2-min step, 8-foot up-and-go (UG), chair sit-and-reach (CSR) and back scratch tests as well as waist circumference. Accordingly, for those variables a different response in each group was evident over the time, supported by a significantly better EG performance in chair stand, arm curl, 2-min step, UG, CSR and back scratch tests from M1 to M3, and a significant increase in MMSE from M1 to M2. The CG's performance decreased over time (M1 to M3) in chair stand, arm curl, 2-min step, UG, CSR, back scratch and MMSE. Results suggest that MT programs may be an important non-pharmacological strategy to improve physical and cognitive functions in institutionalized AD patients. © The Author(s) 2016.

  1. CO 2-induced chemo-mechanical alteration in reservoir rocks assessed via batch reaction experiments and scratch testing

    DOE PAGES

    Aman, Michael; Espinoza, D. Nicolas; Ilgen, Anastasia G.; ...

    2017-09-22

    Here, the injection of carbon dioxide (CO 2) into geological formations results in a chemical re-equilibration between the mineral assemblage and the pore fluid, with ensuing mineral dissolution and re-precipitation. Hence, target rock formations may exhibit changes of mechanical and petrophysical properties due to CO 2 exposure. We conducted batch reaction experiments with Entrada Sandstone and Summerville Siltstone exposed to de-ionized water and synthetic brine under reservoir pressure (9–10 MPa) and temperature (80°C) for up to four weeks. Samples originate from the Crystal Geyser field site, where a naturally occurring CO 2 seepage alters portions of these geologic formations. Wemore » conducted micro-scratch tests on rock samples without alteration, altered under laboratory conditions, and naturally altered over geologic time. Scratch toughness and hardness decrease as a function of exposure time and water salinity up to 52% in the case of Entrada and 87% in the case of Summerville after CO 2-induced alteration in the laboratory. Imaging of altered cores with SEM-EDS and X-ray microCT methods show dissolution of carbonate and silica cements and matrix accompanied by minor dissolution of Fe-oxides, clays, and other silicates. Parallel experiments using powdered samples confirm that dissolution of carbonate and silica are the primary reactions. The batch reaction experiments in the autoclave utilize a high fluid to rock volume ratio and represent an end member of possible alteration associated with CO 2 storage systems. These types of tests serve as a pre-screening tool to identify the susceptibility of rock facies to CO 2-related chemical-mechanical alteration during long-term CO 2 storage.« less

  2. The application of an optical Fourier spectrum analyzer on detecting defects in mass-produced satellite photographs

    NASA Technical Reports Server (NTRS)

    Athale, R.; Lee, S. H.

    1976-01-01

    Various defects in mass-produced pictures transmitted to earth from a satellite are investigated. It is found that the following defects are readily detectable via Fourier spectrum analysis: (1) bit slip, (2) breakup causing loss of image, and (3) disabled track at the top of the imagery. The scratches made on the film during mass production, which are difficult to detect by visual observation, also show themselves readily in Fourier spectrum analysis. A relation is established between the number of scratches, their width and depth and the intensity of their Fourier spectra. Other defects that are found to be equally suitable for Fourier spectrum analysis or visual (image analysis) detection are synchronous loss without blurring of image, and density variation in gray scale. However, the Fourier spectrum analysis is found to be unsuitable for detection of such defects as pin holes, annotation error, synchronous loss with blurring of images, and missing image in the beginning of the work order. The design of an automated, real time system, which will reject defective films, is treated.

  3. SU-F-T-675: Down-Regulating the Expression of Cdc42 and Inhibition of Migration of A549 with Combined Treatment of Ionizing Radiation and Sevoflurane

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

    Feng, Y; Feng, J; Huang, Z

    Purpose: Cdc42 is involved in cell transformation, proliferation, invasion and metastasis of human cancer cells. Cdc42 overexpression has been reported in several types of cancers. This study investigated the combined treatment effects of ionizing radiation and sevoflurane on down-regulating Cdc42 expression and suppressing migration of human adenocarcinoma cell line A549. Methods: Samples of A549 cells with Cdc42 overexpression were created and Cdc42 expression was determined by Western blotting. Increase of migration speed by Cdc42-HA overexpression was confirmed with an initial in-vitro scratch assay. The cells grown in culture media were separated into 2 groups of 6 samples: one for themore » control and the other was treated with 4% sevoflurane for 5hrs prior to a single-fraction radiation of 4Gy using a 6MV beam. Cell migration speeds of the 2 groups were measured with an initial in-vitro scratch assay. The scratch was created with a pipette tip immediately after treatment and images at 4 post-treatment time points (0h, 3h, 6h, 12h) were acquired. The distance between the two separated sides at 0h was used as reference and subsequent changes of the distance over time was defined as the cell migration speed. Image processing and measurement were performed with an in-house software. The experiment was repeated three times independently to evaluate the repeatability and reliability. Statistical analysis was performed with SPSS 19.0. Results: Western blotting showed the treatment down-regulated Cdc42 overexpression. Quantitative analysis and two-tailed t-test showed that cell migration speed of the treated group was higher than the control group at all time points after treatment (p < 0.02). Conclusion: Combined treatment of 6MV photon and sevoflurane can cause the effects of down-regulating Cdc42 overexpression and decrease of migration speed of A549 cells which provides potential of clinical benefit for the cancer therapy. More investigation is needed to further quantify the benefits of the combined therapy.« less

  4. Flexion Reflex Can Interrupt and Reset the Swimming Rhythm.

    PubMed

    Elson, Matthew S; Berkowitz, Ari

    2016-03-02

    The spinal cord can generate the hip flexor nerve activity underlying leg withdrawal (flexion reflex) and the rhythmic, alternating hip flexor and extensor activities underlying locomotion and scratching, even in the absence of brain inputs and movement-related sensory feedback. It has been hypothesized that a common set of spinal interneurons mediates flexion reflex and the flexion components of locomotion and scratching. Leg cutaneous stimuli that evoke flexion reflex can alter the timing of (i.e., reset) cat walking and turtle scratching rhythms; in addition, reflex responses to leg cutaneous stimuli can be modified during cat and human walking and turtle scratching. Both of these effects depend on the phase (flexion or extension) of the rhythm in which the stimuli occur. However, similar interactions between leg flexion reflex and swimming have not been reported. We show here that a tap to the foot interrupted and reset the rhythm of forward swimming in spinal, immobilized turtles if the tap occurred during the swim hip extensor phase. In addition, the hip flexor nerve response to an electrical foot stimulus was reduced or eliminated during the swim hip extensor phase. These two phase-dependent effects of flexion reflex on the swim rhythm and vice versa together demonstrate that the flexion reflex spinal circuit shares key components with or has strong interactions with the swimming spinal network, as has been shown previously for cat walking and turtle scratching. Therefore, leg flexion reflex circuits likely share key spinal interneurons with locomotion and scratching networks across limbed vertebrates generally. The spinal cord can generate leg withdrawal (flexion reflex), locomotion, and scratching in limbed vertebrates. It has been hypothesized that there is a common set of spinal cord neurons that produce hip flexion during flexion reflex, locomotion, and scratching based on evidence from studies of cat and human walking and turtle scratching. We show here that flexion reflex and swimming also share key spinal cord components based on evidence from turtles. Foot stimulation can reset the timing of the swimming rhythm and the response to each foot stimulation can itself be altered by the swim rhythm. Collectively, these studies suggest that spinal cord neuronal networks underlying flexion reflex, multiple forms of locomotion, and scratching share key components. Copyright © 2016 the authors 0270-6474/16/362819-08$15.00/0.

  5. Fatigue Crack Topography.

    DTIC Science & Technology

    1984-01-01

    nominal cycle frequency of 15 Hz. Buckling of the specimens during compression loading was prevented by felt-lined aluminium alloy antibuckling guides...evaluating ciack initiation time and crack propagation, prgram I was used for performing the major fatigue test with the aircraft structure. In...direction of the notch to prevent scratches in the through-the-thickness direction. Prior to testing, the notch surfaces were lightly etched to reveal

  6. Characteristics of ZrC/Ni-UDD coatings for a tungsten carbide cutting tool

    NASA Astrophysics Data System (ADS)

    Chayeuski, V. V.; Zhylinski, V. V.; Rudak, P. V.; Rusalsky, D. P.; Višniakov, N.; Černašėjus, O.

    2018-07-01

    This work deals with the features of the structure of combined ZrC/Ni-ultradisperse diamonds (UDD) coating synthesized by electroplating and cathode arc evaporation physical vapor deposition (CAE-PVD) techniques on the tungsten carbide WC - 2 wt% Co on cutting inserts to improve tool life. The microstructure, phase composition, and micro-scratch test analysis of the ZrC/Ni-UDD coating were studied. The ZrC/Ni-UDD coating consists of separate phases of zirconium carbide ZrC, α-Ni, and Ni-UDD phase. The surface morphology of the coating shows a pattern with pits, pores, and particles. Separated nanodiamond particles are present in the pores of the combined coating. Therefore, the structure of the bottom layer of Ni-UDD affects the morphology of the surface of the ZrC/Ni-UDD coating. The obtained value of the critical loads on the scratch track of the coating in 26 N proves a sufficiently high value of the adhesion strength of the intermediate Ni-UDD-layer with hard alloy of WC-Co substrate. Due to their unique structure ZrC/Ni-UDD-coatings can be used to increase the durability period of a wood-cutting milling tool for cutting chipboard by CNC machines.

  7. Enhanced scratching evoked by PAR-2 agonist and 5-HT but not histamine in a mouse model of chronic dry skin itch.

    PubMed

    Akiyama, T; Carstens, M Iodi; Carstens, E

    2010-11-01

    Chronic itch is a symptom of many skin conditions and systemic disease, and it has been hypothesized that the chronic itch may result from sensitization of itch-signaling pathways. We induced experimental chronic dry skin on the rostral back of mice, and observed a significant increase in spontaneous hindlimb scratches directed to the dry skin. Spontaneous scratching was significantly attenuated by a PAR-2 antibody and 5-HT2A receptor antagonist, indicating activation of these receptors by endogenous mediators released under dry skin conditions. We also observed a significant increase in the number of scratch bouts evoked by acute intradermal injections of a protease-activated receptor (PAR)-2 agonist and serotonin (5-HT), but not histamine. We additionally investigated if pruritogen-evoked activity of dorsal root ganglion (DRG) neurons is enhanced in this model. DRG cells from dry skin mice exhibited significantly larger responses to the PAR-2 agonist and 5-HT, but not histamine. Spontaneous scratching may reflect ongoing itch, and enhanced pruritogen-evoked scratching may represent hyperknesis (enhanced itch), both potentially due to sensitization of itch-signaling neurons. The correspondence between enhanced behavioral scratching and DRG cell responses suggest that peripheral pruriceptors that respond to proteases and 5-HT, but not histamine, may be sensitized in dry skin itch. Copyright © 2010 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  8. Unclaimed Prize Information Biases Perceptions of Winning in Scratch Card Gambling.

    PubMed

    Walker, Alexander C; Stange, Madison; Fugelsang, Jonathan A; Koehler, Derek J; Dixon, Mike J

    2018-03-29

    Unclaimed prize information (i.e., the number of prizes still available to be won) is information commonly provided to scratch card gamblers. However, unless the number of tickets remaining to be purchased is also provided, this information is uninformative. Despite its lack of utility in assisting gamblers in choosing the most favourable type of scratch card to play, we hypothesized that unclaimed prize information would bias participants' judgments within a scratch card gambling context. In Experiment 1 (N = 201), we showed that participants are influenced by this information such that they felt more likely to win, were more excited to play, and preferred to hypothetically purchase more of the scratch card with the greatest number of unclaimed prizes. In Experiment 2 (N = 201), we attempted to ameliorate this bias by providing participants with the number of tickets remaining to be purchased and equating the payback percentages of all three games. The bias, although attenuated, still persisted in these conditions. Finally, in Experiment 3 (N = 200), we manipulated the hypothetical scratch cards such that games with the highest number of unclaimed prizes were the least favourable, and vice versa. As in Experiment 2, participants still favoured cards with greater numbers of unclaimed prizes. Possible mechanisms underlying this bias are discussed. In conclusion, across three experiments, we demonstrate that salient unclaimed prize information is capable of exerting a strong effect over judgments related to scratch card games.

  9. Epidemiologic and clinical aspects of animal bite injuries.

    PubMed

    Kizer, K W

    1979-04-01

    During 1975, 332 animal bite injuries accounted for 1.2% of all surgical problems treated at the UCLA Hospital Emergency Department. Data on 307 bite injuries were available and analyzed for environmental, animal, human, interaction, and clinical factors. More than half of the dog bites and almost three fourths of the cat bites-scratches happened at or near the victims' homes. Dog bites were almost twice as common among men, while cat bites-scratches were twice as common among women. Of the incidents in which ownership information was available, 85% of dog bites and 80% of cat bites-scratches were from an animal belonging to the victim, his family or friends, or another known person. Forty-three percent of dog bites, and 52% of cat bites-scratches were provoked, that is, happened while the victim was interacting with the animal. Of bites of the head and/or neck, 38% injured the upper lip; 17% of dog bites injured the eye or adjacent tissues; 48% were in children less than ten-years-old. On fifth of cat bites-scratches involved the head and/or neck, 60% of these injured orbital or periorbital tissues. Over 2% of patients were hospitalized. Five percent of dog bite victims and 29% of cat bite-scratch victims returned with complications, mostly cellulitis or lymphangitis. Pasteurella multocida was the most common pathogen cultured, as evidenced by the 50% and 80% culture-positive rates for dog and cat bite-scratches respectively in this series.

  10. Immediate-type allergic and protease-mediated reactions are involved in scratching behaviour induced by topical application of Dermatophagoides farinae extract in NC/Nga mice.

    PubMed

    Yamada, Yoshihito; Ueda, Yuhki; Nakamura, Aki; Kanayama, Shoji; Tamura, Rie; Hashimoto, Kei; Matsumoto, Tatsumi; Ishii, Ritsuko

    2018-04-01

    Atopic dermatitis (AD)-like dermatitis can be induced by repeated topical application of an ointment containing Dermatophagoides farinae body (Dfb) extract in NC/Nga mice. This AD-like murine model also exhibits a biphasic increase in the number of scratching behaviour after topical application of Dfb ointment. In this study, we investigated the possible mechanisms underlying the scratching behaviour in each phase. An increase in the content of mast cell-derived mediators such as histamine and 5-hydroxytryptamine in the lesional skin and increased vascular permeability were observed in the early phase after the Dfb ointment application. Chlorpheniramine (H 1 receptor antagonist) and cromoglycate (mast cell stabilizer) reduced the scratching behaviour in the early phase but not that in the later phase. Furthermore, the content of various endogenous pruritogens such as interleukin-31 and thymic stromal lymphopoietin in the lesional skin was increased 1 or 24 hours after the Dfb ointment application. Elevated expression of proteinase-activated receptor-2 (PAR-2) was also observed in the epidermis. Finally, gabexate (serine protease inhibitor) reduced the scratching behaviour in both phases, and anti-PAR2 antibody also showed a tendency to reduce both scratching behaviours. These findings suggest that immediate-type allergic reactions caused by mast cell degranulation and PAR-2 activation by proteases are involved in the scratching behaviour in this AD-like model. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Physical fitness is associated with anxiety levels in women with fibromyalgia: the al-Ándalus project.

    PubMed

    Córdoba-Torrecilla, S; Aparicio, V A; Soriano-Maldonado, A; Estévez-López, F; Segura-Jiménez, V; Álvarez-Gallardo, I; Femia, P; Delgado-Fernández, M

    2016-04-01

    To assess the independent associations of individual physical fitness components with anxiety in women with fibromyalgia and to test which physical fitness component shows the greatest association. This population-based cross-sectional study included 439 women with fibromyalgia (age 52.2 ± 8.0 years). Anxiety symptoms were measured with the State Trait Anxiety Inventory (STAI) and the anxiety item of the Revised Fibromyalgia Impact Questionnaire (FIQR). Physical fitness was assessed through the Senior Fitness Test battery and handgrip strength test. Overall, lower physical fitness was associated with higher anxiety levels (all, p < 0.05). The coefficients of the optimal regression model (stepwise selection method) between anxiety symptoms and physical fitness components adjusted for age, body fat percentage and anxiolytics intake showed that the back scratch test (b = -0.18), the chair sit-and-reach test (b = -0.12; p = 0.027) and the 6-min walk test (b = -0.02; p = 0.024) were independently and inversely associated with STAI. The back scratch test and the arm- curl test were associated with FIQR-anxiety (b = -0.05; p < 0.001 and b = -0.07; p = 0.021, respectively). Physical fitness was inversely and consistently associated with anxiety in women with fibromyalgia, regardless of the fitness component evaluated. In particular, upper-body flexibility was an independent indicator of anxiety levels, followed by cardiorespiratory fitness and muscular strength.

  12. Investigating the Role of Computer-Supported Annotation in Problem-Solving-Based Teaching: An Empirical Study of a Scratch Programming Pedagogy

    ERIC Educational Resources Information Center

    Su, Addison Y. S.; Yang, Stephen J. H.; Hwang, Wu-Yuin; Huang, Chester S. J.; Tern, Ming-Yu

    2014-01-01

    For more than 2 years, Scratch programming has been taught in Taiwanese elementary schools. However, past studies have shown that it is difficult to find appropriate learning methods or tools to boost students' Scratch programming performance. This inability to readily identify tutoring tools has become one of the primary challenges addressed in…

  13. Human bubonic plague transmitted by a domestic cat scratch.

    PubMed

    Weniger, B G; Warren, A J; Forseth, V; Shipps, G W; Creelman, T; Gorton, J; Barnes, A M

    1984-02-17

    Bubonic plague was transmitted to a 10-year-old girl in Oregon by a scratch wound inflicted by a domestic cat. The cat probably was infected by contact with infected wild rodents or their fleas. Yersinia pestis was identified in Diamanus montanus fleas collected from an abandoned burrow near the patient's home. Domestic cats may infect humans with Y pestis by inoculation from a scratch.

  14. An Investigation of the Effects of Programming with Scratch on the Preservice IT Teachers' Self-Efficacy Perceptions and Attitudes towards Computer Programming

    ERIC Educational Resources Information Center

    Yukselturk, Erman; Altiok, Serhat

    2017-01-01

    The purpose of this study was to analyze the effects of programming with Scratch on the views of preservice Information Technology (IT) teachers towards computer programming. The study sample consisted of 151 preservice IT teachers who took an elective course including a Scratch module in the 2013-14 academic year. Three online questionnaires…

  15. Comparison of the impact of scaler material composition on polished titanium implant abutment surfaces.

    PubMed

    Hasturk, Hatice; Nguyen, Daniel Huy; Sherzai, Homa; Song, Xiaoping; Soukos, Nikos; Bidlack, Felicitas B; Van Dyke, Thomas E

    2013-08-01

    The purpose of this study was to compare the impact of the removal of biofilm with hand scalers of different material composition on the surface of implant abutments by assessing the surface topography and residual plaque after scaling using scanning electron microscopy (SEM). Titanium implant analogs from 3 manufacturers (Straumann USA LLC, Andover, Maine, Nobel BioCare USA LLC, Yorba Linda, Cali, Astra Tech Implant Systems, Dentsply, Mölndal, Sweden) were mounted in stone in plastic vials individually with authentic prosthetic abutments. Plaque samples were collected from a healthy volunteer, inoculated into growth medium and incubated with the abutments anaerobically for 1 week. A blinded, calibrated hygienist performed scaling to remove the biofilm using 6 implant scalers (in triplicate), 1 scaler for 1 abutment. The abutments were mounted on an imaging stand and processed for SEM. Images were captured in 3 randomly designated areas of interest on each abutment. Analysis of the implant polished abutment surface and plaque area measurements were performed using ImageJ image analysis software. Surface alterations were characterized by the number, length, depth and the width of the scratches observed. Glass filled resin scalers resulted in significantly more and longer scratches on all 3 abutment types compared to other scalers, while unfilled resin scalers resulted in the least surface change (p < 0.05). Filled resin-graphite reinforced scalers, carbon fiber reinforced resin scalers and titanium scalers resulted in more superficial scratches compared to glass filled resin, as well as more scratches than unfilled resin. No statistically significant differences were found between scalers and abutments with regard to plaque removal. The impact of scalers on implant abutment surfaces varies between abutment types presumably due to different surface characteristics with no apparent advantage of one abutment type over the other with regard to resistance to surface damage. Unfilled resin was found consistently to be the least damaging to abutment surfaces, although all scalers of all compositions caused detectable surface changes to polished surfaces of implant abutments.

  16. The effects of the phyllolitorin analogue [desTrp3,Leu8]phyllolitorin on scratching induced by bombesin and related peptides in rats

    PubMed Central

    Johnson, Mark D.; Ko, Mei-Chuan; Choo, Kevin S.; Traynor, John R.; Mosberg, Henry I.; Naughton, Norah N.; Woods, James H.

    2010-01-01

    Bombesin along with several closely related neuropeptides elicit scratching behavior when administered centrally. The first part of the study was designed to determine the antagonistic effects of a novel phyllolitorin analogue wdesTrp3,Leu8]phyllolitorin (DTP) on scratching induced by three peptides (bombesin, neuromedin-C, and [Leu8]phyllolitorin). In addition, the binding affinity of each peptide for the bombesin receptor site was determined. DTP (30 μg) inhibited scratching induced by these peptides, but unlike the peptides, DTP had no affinity for the bombesin site, thereby suggesting that DTP is displaying physiological antagonism through an unknown mechanism. PMID:10482814

  17. [Eye and cat scratch disease: A case series].

    PubMed

    Deschasse, C; Bielefeld, P; Muselier, A; Bour, J B; Besancenot, J F; Garcher, C C; Bron, A M

    2016-02-01

    Cat scratch disease is a pleiomorphic condition, sometimes with isolated ophthalmic involvement. We report the clinical observations of seven cases with ophthalmologic manifestations of cat scratch disease. There were seven patients, with a median age of 52 years, of whom five were women and three had unilateral involvement. Six exhibited Leber's stellate neuroretinitis, an incomplete syndrome in two cases, and one associated with chorioretinal foci. One patient had isolated retinal infiltrates. The diagnosis of cat scratch disease was confirmed by Bartonella henselae serology, positive in all cases. All patients received treatment with doxycycline. Ocular complications (with optic atrophy and macular retinal pigment epithelial changes) were noted in five cases. Ocular bartonellosis is an atypical clinical form. It requires a directed ancillary work-up with serology or PCR, which has the peculiarity of being highly specific if not very sensitive. Treatment is above all preventive. Antibiotics may be initiated. Cat scratch disease must be excluded in the work-up of posterior uveitis. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  18. Research on the Stress and Material Flow with Single Particle—Simulations and Experiments

    NASA Astrophysics Data System (ADS)

    Zhang, Tao; Jiang, Feng; Yan, Lan; Xu, Xipeng

    2017-04-01

    The scratching process of particle is a complex material removal process involving cutting, plowing, and rubbing. In this study, scratch experiments under different loads are performed on a multifunctional tester for material surface. Natural diamond and Fe-Cr-Ni stainless steel are chosen as indenter and workpiece material, respectively. The cutting depth and side flow height of scratch are measured using a white light interferometer. The finite element model is developed, and the numerical simulation of scratching is conducted using AdvantEdgeTM. The simulated forces and side flow height under different cutting depths correspond well with experimental results, validating the accuracy of the scratching simulation. The mises stress distribution of the particle is presented, with the maximum stress occurring inside the particle rather than on the surface. The pressure distribution of the particle is also given, and results show that the maximum pressure occurs on the contact surface of particle and workpiece. The material flow contour is presented, and material flow direction and velocity magnitude are analyzed.

  19. General Halleck's itchy elbows.

    PubMed

    Cropley, Thomas G

    2007-01-01

    General Henry Wager Halleck served as general-in-chief and chief of staff of the Federal army from 1862-1865. Unpopular with troops as well as with many members of the Lincoln administration, he was a particular source of irritation to Secretary of Navy Gideon Welles. In his posthumously-published diary of the war years, Welles viciously criticized Halleck for his failings as army commander. Welles also derided Halleck's personality and personal appearance. Welles found the general's habitual elbow-scratching annoying enough to mention it in five separate diary entries. This depiction of Halleck ceaselessly, nervously scratching his elbows has entered Civil War folklore. Why did Halleck scratch his elbows? Two possibilities exist. Either he did so compulsively, as a nervous habit, or he was scratching an itch. In this paper, I present a speculative argument that Halleck may have had a skin disease, possibly atopic dermatitis, and that this may have contributed to or have been the sole cause of his elbow scratching.

  20. Characteristics and in vitro response of thin hydroxyapatite–titania films produced by plasma electrolytic oxidation of Ti alloys in electrolytes with particle additions

    PubMed Central

    Yeung, W. K.; Sukhorukova, I. V.; Shtansky, D. V.; Levashov, E. A.; Zhitnyak, I. Y.; Gloushankova, N. A.; Kiryukhantsev-Korneev, P. V.; Petrzhik, M. I.; Matthews, A.

    2016-01-01

    The enhancement of the biological properties of Ti by surface doping with hydroxyapatite (HA) is of great significance, especially for orthodontic applications. This study addressed the effects of HA particle size in the electrolyte suspension on the characteristics and biological properties of thin titania-based coatings produced on Ti–6Al–4V alloy by plasma electrolytic oxidation (PEO). Detailed morphological investigation of the coatings formed by a single-stage PEO process with two-step control of the electrical parameters was performed using the Minkowski functionals approach. The surface chemistry was studied by glow discharge optical emission spectroscopy and Fourier transform infrared spectroscopy, whereas mechanical properties were evaluated using scratch tests. The biological assessment included in vitro evaluation of the coating bioactivity in simulated body fluid (SBF) as well as studies of spreading, proliferation and osteoblastic differentiation of MC3T3-E1 cells. The results demonstrated that both HA micro- and nanoparticles were successfully incorporated in the coatings but had different effects on their surface morphology and elemental distributions. The micro-particles formed an irregular surface morphology featuring interpenetrated networks of fine pores and coating material, whereas the nanoparticles penetrated deeper into the coating matrix which retained major morphological features of the porous TiO2 coating. All coatings suffered cohesive failure in scratch tests, but no adhesive failure was observed; moreover doping with HA increased the coating scratch resistance. In vitro tests in SBF revealed enhanced bioactivity of both HA-doped PEO coatings; furthermore, the cell proliferation/morphometric tests showed their good biocompatibility. Fluorescence microscopy revealed a well-organised actin cytoskeleton and focal adhesions in MC3T3-E1 cells cultivated on these substrates. The cell alkaline phosphatase activity in the presence of ascorbic acid and β-glycerophosphate was significantly increased, especially in HA nanoparticle-doped coatings. PMID:27019704

  1. Scratched: World War II Airborne Operations That Never Happened

    DTIC Science & Technology

    2014-05-22

    Approved for Public Release; Distribution is Unlimited SCRATCHED: WORLD WAR II AIRBORNE OPERATIONS THAT NEVER HAPPENED A Monograph by...2. REPORT TYPE Master’s Thesis 3. DATES COVERED (From - To) JUN 2013-MAY 2014 4. TITLE AND SUBTITLE Scratched: World War II Airborne...Maastricht gap, to get Allied troops through the West Wall. For numerous reasons, the overall Allied airborne effort of World War II provided mixed

  2. Shale-brine-CO2 interactions and the long-term stability of carbonate-rich shale caprock

    NASA Astrophysics Data System (ADS)

    Ilgen, A.; Aman, M.; Espinoza, D. N.; Rodriguez, M. A.; Griego, J.; Dewers, T. A.; Feldman, J.; Stewart, T.; Choens, R. C., II

    2017-12-01

    Geological carbon storage (GCS) requires an impermeable caprock (e.g., shale) that prevents the upward migration and escape of carbon dioxide (CO2) from the subsurface. Geochemical alteration can occur at the caprock-reservoir rock interface, which could lead to the altering of the rock's mechanical properties, compromising the seal. We performed laboratory experiments on Mancos shale to quantify the coupled chemical-mechanical response of carbonate-rich shale in CO2-brine mixtures at conditions typical to GCS. We constructed geochemical models, calibrated them using laboratory results, and extended to time scales required for GCS. We observed the dissolution of calcite and kaolinite and the precipitation of gypsum and amorphous aluminum (hydr)oxide following the introduction of CO2. To address whether this mineral alteration causes changes in micro-mechanical properties, we examined altered Mancos shale using micro-mechanical (scratch) testing, measuring the scratch toughness of mm-scale shale lithofacies. The quartz-rich regions of the Mancos shale did not show significant changes in scratch toughness following 1-week alteration in a CO2-brine mixture. However, the scratch toughness of the calcite-rich, originally softer regions decreased by about 50%. These observations illustrate a coupled and localized chemical-mechanical response of carbonate-rich shale to the injection of CO2. This suggests a localized weakening of the caprock may occur, potentially leading to the development of preferential flow paths. The identification of vulnerable lithofacies within caprock and a characterization of mineralogical heterogeneity is imperative at prospective GCS sites. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA-0003525.

  3. Active learning reduces annotation time for clinical concept extraction.

    PubMed

    Kholghi, Mahnoosh; Sitbon, Laurianne; Zuccon, Guido; Nguyen, Anthony

    2017-10-01

    To investigate: (1) the annotation time savings by various active learning query strategies compared to supervised learning and a random sampling baseline, and (2) the benefits of active learning-assisted pre-annotations in accelerating the manual annotation process compared to de novo annotation. There are 73 and 120 discharge summary reports provided by Beth Israel institute in the train and test sets of the concept extraction task in the i2b2/VA 2010 challenge, respectively. The 73 reports were used in user study experiments for manual annotation. First, all sequences within the 73 reports were manually annotated from scratch. Next, active learning models were built to generate pre-annotations for the sequences selected by a query strategy. The annotation/reviewing time per sequence was recorded. The 120 test reports were used to measure the effectiveness of the active learning models. When annotating from scratch, active learning reduced the annotation time up to 35% and 28% compared to a fully supervised approach and a random sampling baseline, respectively. Reviewing active learning-assisted pre-annotations resulted in 20% further reduction of the annotation time when compared to de novo annotation. The number of concepts that require manual annotation is a good indicator of the annotation time for various active learning approaches as demonstrated by high correlation between time rate and concept annotation rate. Active learning has a key role in reducing the time required to manually annotate domain concepts from clinical free text, either when annotating from scratch or reviewing active learning-assisted pre-annotations. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Increased Urge to Gamble Following Near-Miss Outcomes May Drive Purchasing Behaviour in Scratch Card Gambling.

    PubMed

    Stange, Madison; Graydon, Candice; Dixon, Mike J

    2017-09-01

    Previous research into scratch card gambling has highlighted the effects of these games on players' arousal and affective states. Specifically, near-miss outcomes in scratch cards (uncovering 2 of 3 needed jackpot symbols) have been associated with high levels of physiological and subjective arousal and negative emotional evaluations, including increased frustration. We sought to extend this research by examining whether near-misses prompted increases in gambling urge, and the subsequent purchasing of additional scratch cards. Participants played two scratch cards with varying outcomes with half of the sample experiencing a near-miss for the jackpot prize, and the other half experiencing a regular loss. Players rated their urge to continue gambling after each game outcome, and following the initial playing phase, were then able to use their winnings to purchase additional cards. Our results indicated that near-misses increased the urge to gamble significantly more than regular losses, and urge to gamble in the near-miss group was significantly correlated with purchasing at least one additional card. Although some players in the loss group purchased another card, there was no correlation between urge to gamble and purchasing in this group. Additionally, participants in the near-miss group who purchased additional cards reported higher levels of urge than those who did not purchase more cards. This was not true for the loss group: participants who experienced solely losing outcomes reported similar levels of urge regardless of whether or not they purchased more scratch cards. Despite near-misses' objective status as monetary losses, the increased urge that follows near-miss outcomes may translate into further scratch card gambling for a subset of individuals .

  5. Gambling-Related Attitudes and Behaviors in Adolescents Having Received Instant (Scratch) Lottery Tickets as Gifts

    PubMed Central

    Kundu, Priya V.; Pilver, Corey E.; Desai, Rani A.; Steinberg, Marvin A.; Rugle, Loreen; Krishnan-Sarin, Suchitra; Potenza, Marc N.

    2012-01-01

    Objective Instant (scratch) lottery ticket gambling is popular among adolescents. Prior research has not determined whether adolescents’ gambling behavior and attitudes toward gambling are influenced by the receipt of scratch lottery tickets as gifts. Method Cross-sectional survey data from 2,002 Connecticut high school students with past-year gambling were analyzed using bivariate approaches and logistic regression analyses. Interactions between gambling-problem severity and lottery-gift status were examined in relation to multiple outcomes. Results Adolescents who received a scratch lottery ticket as a gift compared with those who did not were more likely to report features of problem gambling, buy scratch lottery tickets for themselves, and buy and receive other types of lottery tickets; they were also less likely to report parental disapproval of gambling and to see gambling prevention efforts as important. Later (≥15 years) age-at-gambling-onset was inversely linked to gambling-problem severity in the lottery gift group (odds ratio [OR] = .38) but not in the nongift group (OR = .91), yielding a significant severity by gift status interaction. Other academic, health, and gambling-related correlates of gambling-problem severity were similar in the gift and nongift groups. Conclusions For adolescents, the receipt of scratch lottery tickets as gifts during childhood or adolescence was associated with risky/problematic gambling and with gambling-related attitudes, behaviors, and views suggesting greater gambling acceptability. The extent to which the receipt of scratch lottery tickets may promote gambling behaviors and the development of gambling problems warrants consideration. Education, prevention, and treatment strategies should incorporate findings relating to receipt of gambling products by underage individuals. PMID:23299004

  6. Preliminary evaluation of adhesion strength measurement devices for ceramic/titanium matrix composite bonds

    NASA Technical Reports Server (NTRS)

    Pohlchuck, Bobby; Zeller, Mary V.

    1992-01-01

    The adhesive bond between ceramic cement and a titanium matrix composite substrate to be used in the National Aerospace Plane program is evaluated. Two commercially available adhesion testers, the Sebastian Adherence Tester and the CSEM REVETEST Scratch Tester, are evaluated to determine their suitability for quantitatively measuring adhesion strength. Various thicknesses of cements are applied to several substrates, and bond strengths are determined with both testers. The Sabastian Adherence Tester has provided limited data due to an interference from the sample mounting procedure, and has been shown to be incapable of distinguishing adhesion strength from tensile and shear properties of the cement itself. The data from the scratch tester has been found to be difficult to interpret due to the porosity and hardness of the cement. Recommendations are proposed for a more reliable adhesion test method.

  7. Cat-scratch disease: unusual perivascular chorioretinal lesions.

    PubMed

    Sahin, Ozlem

    2014-01-01

    This study is a case report of bilateral perivascular chorioretinal lesions associated with Bartonella henselae. A 37-year-old woman presented with headache and blurred vision in both eyes aggravating occasionally during five years. She was otherwise healthy, with best-corrected visual acuities were 20/20 in both eyes. History of close contact with cats was more than merely eye-catching upon examination of her fundus. In both eyes, fundi were coated with yellow-brown pigmented perivenous chorioretinal lesions along the superotemporal and inferotemporal vascular arcades and their branches. The perivenous lesions were associated with vascular fibrous bands and corresponding changes in vascular calibers. There were no associated intraocular inflammatory signs in both eyes. The serologic tests confirmed the diagnosis of cat-scratch disease. The patient received no treatment, and she was followed for three years without any signs of ocular inflammation.

  8. [Readjustment of the efferent activity of the scratching generator in response to stimulation of muscle afferents of the hindlimb of the decerebrate immobilized cat].

    PubMed

    Shimanskiĭ, Iu P; Baev, K V

    1987-01-01

    Rebuildings of the scratching generator activity caused by phasic electrical stimulation of ipsilateral hindlimb muscle nerves during different hindlimb positions were studied in decerebrated immobilized cats. Strong dependence of these rebuildings on the stimulation phase was observed. The character of the "scratch" cycle duration rebuilding was formed by the scratching generator tendency to bring efferent activity into such correlation with the stimulus that the stimulation moment coincided with the moment of efferent activity phase triggering. Phasic altering of the efferent activity intensity rebuilding was observed against a background of "aiming" and "scratching" activity correlation shift in the direction of strengthening activation of muscles innervated by the stimulated nerve. This rebuilding was intensified when the hindlimb deflects from the aimed position in the direction of corresponding muscles stretching. Physiological sense of "rebuilding absence phases" is discussed. It is postulated that absence of the duration and intensity changes can be achieved simultaneously only with definite correlation between phase and intensity of the afferent impulsation burst.

  9. Robust automatic line scratch detection in films.

    PubMed

    Newson, Alasdair; Almansa, Andrés; Gousseau, Yann; Pérez, Patrick

    2014-03-01

    Line scratch detection in old films is a particularly challenging problem due to the variable spatiotemporal characteristics of this defect. Some of the main problems include sensitivity to noise and texture, and false detections due to thin vertical structures belonging to the scene. We propose a robust and automatic algorithm for frame-by-frame line scratch detection in old films, as well as a temporal algorithm for the filtering of false detections. In the frame-by-frame algorithm, we relax some of the hypotheses used in previous algorithms in order to detect a wider variety of scratches. This step's robustness and lack of external parameters is ensured by the combined use of an a contrario methodology and local statistical estimation. In this manner, over-detection in textured or cluttered areas is greatly reduced. The temporal filtering algorithm eliminates false detections due to thin vertical structures by exploiting the coherence of their motion with that of the underlying scene. Experiments demonstrate the ability of the resulting detection procedure to deal with difficult situations, in particular in the presence of noise, texture, and slanted or partial scratches. Comparisons show significant advantages over previous work.

  10. Dragonfly: strengthening programming skills by building a game engine from scratch

    NASA Astrophysics Data System (ADS)

    Claypool, Mark

    2013-06-01

    Computer game development has been shown to be an effective hook for motivating students to learn both introductory and advanced computer science topics. While games can be made from scratch, to simplify the programming required game development often uses game engines that handle complicated or frequently used components of the game. These game engines present the opportunity to strengthen programming skills and expose students to a range of fundamental computer science topics. While educational efforts have been effective in using game engines to improve computer science education, there have been no published papers describing and evaluating students building a game engine from scratch as part of their course work. This paper presents the Dragonfly-approach in which students build a fully functional game engine from scratch and make a game using their engine as part of a junior-level course. Details on the programming projects are presented, as well as an evaluation of the results from two offerings that used Dragonfly. Student performance on the projects as well as student assessments demonstrates the efficacy of having students build a game engine from scratch in strengthening their programming skills.

  11. Noxious heat and scratching decrease histamine-induced itch and skin blood flow.

    PubMed

    Yosipovitch, Gil; Fast, Katharine; Bernhard, Jeffrey D

    2005-12-01

    The aim of this study was to assess the effect of thermal stimuli or distal scratching on skin blood flow and histamine-induced itch in healthy volunteers. Twenty-one healthy volunteers participated in the study. Baseline measurements of skin blood flow were obtained on the flexor aspect of the forearm. These measurements were compared with skin blood flow after various stimuli: heating the skin, cooling the skin, noxious cold 2 degrees C, noxious heat 49 degrees C, and scratching via a brush with controlled pressure. Afterwards histamine iontophoresis was performed and skin blood flow and itch intensity were measured immediately after the above-mentioned stimuli. Scratching reduced mean histamine-induced skin blood flow and itch intensity. Noxious heat pain increased basal skin blood flow but reduced histamine-induced maximal skin blood flow and itch intensity. Cold pain and cooling reduced itch intensity, but neither affected histamine-induced skin blood flow. Sub-noxious warming the skin did not affect the skin blood flow or itch intensity. These findings suggest that heat pain and scratching may inhibit itch through a neurogenic mechanism that also affects skin blood flow.

  12. Relations between the characteristics and psychological comorbidities of chronic pruritus differ between men and women: women are more anxious than men.

    PubMed

    Stumpf, A; Ständer, S; Warlich, B; Fritz, F; Bruland, P; Pfleiderer, B; Heuft, G; Schneider, G

    2015-01-01

    Although sex and gender are becoming more important in diagnostics and therapy, there is still little knowledge about sex-specific differences in chronic pruritus (CP). To compare, taking into consideration the characteristics of pruritus, sex-specific differences in psychological symptoms in patients with CP. Sociodemographic data, data on the clinical characteristics of the skin and CP were documented over a 1-year period in all patients attending the Competence Center Chronic Pruritus of the University Hospital Münster for the first time. All patients completed the Hospital Anxiety and Depression Scale. Student's t-tests for independent study groups and linear regression analyses were applied. A total of 619 patients (278 men, 341 women) were included in the analysis. Women were more anxious than men, but were not more depressed. A linear regression analysis indicated that depression and anxiety scores in women were related to the average intensity of pruritus during the previous 4 weeks and to a more generalized pruritus at the beginning of CP; older age in women also correlated with the scores on the depression subscale. Interestingly, the associations were different in men: scores on the depression scale were associated with the diagnosis of CP pruritus with multiple scratch lesions. There are sex-specific differences in the relationship between the psychological symptoms and clinical characteristics of CP; higher anxiety scores were achieved by women. Whether psychological symptoms can be reversed when CP and scratch lesions improve is an issue that needs further exploration. © 2014 British Association of Dermatologists.

  13. Cat Scratch Disease

    MedlinePlus

    Cat scratch disease (CSD) is an illness caused by the bacterium Bartonella henselae. Almost half of all cats carry the infection ... symptoms of CSD, call your doctor. Centers for Disease Control and Prevention

  14. Cat scratch disease in an immunosuppressed patient with systemic lupus erythematosus.

    PubMed

    Vargas-Hitos, J A; Sabio, J M; Navarrete-Navarrete, N; Arenas-Miras, M del M; Zamora-Pasadas, M; Jiménez-Alonso, J

    2016-03-01

    Cat scratch disease is an infectious disorder transmitted by cats that typically affects children and young adults. Immunosuppression is a well-known risk factor for the development of severe and atypical forms of the disease; hence it is under-diagnosed in patients with compromised immunity. We are reporting the first case of cat scratch disease, which presented as fever and fatigue, in a patient with systemic lupus erythematosus while receiving immunosuppressant therapy after a kidney transplant. © The Author(s) 2015.

  15. A Balance Sheet for Educational Item Banking.

    ERIC Educational Resources Information Center

    Hiscox, Michael D.

    Educational item banking presents observers with a considerable paradox. The development of test items from scratch is viewed as wasteful, a luxury in times of declining resources. On the other hand, item banking has failed to become a mature technology despite large amounts of money and the efforts of talented professionals. The question of which…

  16. Bubble formation in microgravity

    NASA Technical Reports Server (NTRS)

    Antar, Basil N.

    1994-01-01

    Two KC-135 flight campaigns have been conducted to date which are specifically dedicated to study bubble formation in microgravity. The first flight was conducted during March 14-18, 1994, and the other during June 20-24, 1994. The results from the June 1994 flight have not been analyzed yet, while the results from the March flight have been partially analyzed. In the first flight three different experiments were performed, one with the specific aim at determining whether or not cavitation can take place during any of the fluid handling procedures adopted in the shuttle bioprocessing experiments. The other experiments were concerned with duplicating some of the procedures that resulted in bubble formation, namely the NCS filling procedure and the needle scratch of a solid surface. The results from this set of experiments suggest that cavitation did not take place during any of the fluid handling procedures. The results clearly indicate that almost all were generated as a result of the breakup of the gas/liquid interface. This was convincingly demonstrated in the scratch tests as well as in the liquid fill tests.

  17. A star in the eye: cat scratch neuroretinitis.

    PubMed

    Gajula, Viswanath; Kamepalli, Ravi; Kalavakunta, Jagadeesh K

    2014-02-01

    Neuroretinitis is one of the atypical presentations of Cat scratch disease (CSD). Fundoscopy showed star pattern macular exudates. CSD should be considered in patients who present with blurry vision and typical fundoscopic findings.

  18. Therapeutic Effects of Korean Red Ginseng Extract in a Murine Model of Atopic Dermatitis: Anti-pruritic and Anti-inflammatory Mechanism

    PubMed Central

    2017-01-01

    Korean red ginseng (KRG) and ginsenosides exhibit diverse biological effects, including anti-inflammatory and anti-allergic. We aimed to investigate the therapeutic effect of KRG in a murine model of atopic dermatitis (AD) is mediated whether by diminishing the pruritus or by suppressing the inflammation. Thirty NC/Nga mice were randomly divided to 5 groups. AD-like skin lesions were induced by percutaneous challenge with 2,4,6-trinitro-1-chrolobenzene (TNCB) on the ears and backs of NC/Nga mice. KRG extract, evening primrose oil, cyclosporine, and phosphate-buffered saline were administered orally by a gastric tube. Each study group was also divided into scratching-permitted and scratching-restricted subgroups to evaluate the impact of scratching behavior on AD. The effects of KRG and the other agents were assessed by measuring the clinical severity score, ear thickness, extent of transepidermal water loss (TEWL), number of scratching movements, total systemic immunoglobulin E (IgE) and interleukin (IL)-31 levels, histologic changes of cutaneous lesions, and mRNA expression levels of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, thymic stromal lymphopoietin (TSLP), and IL-31. KRG exerts therapeutic effects against AD by inhibiting the T helper 2 (Th2) mediated inflammation as well as by diminishing the itching sensation. Moreover, restricting scratching behavior suppresses the vicious cycle of itching and scratching, thus reducing clinical and systemic inflammation in our murine model of AD. PMID:28244297

  19. Micromechanical Tests and Geochemical Modeling to Evaluate Evolution of Rock Alteration by CO2-Water Mixtures

    NASA Astrophysics Data System (ADS)

    Aman, M.; Sun, Y.; Ilgen, A.; Espinoza, N.

    2015-12-01

    Injection of large volumes of CO2 into geologic formations can help reduce the atmospheric CO2 concentration and lower the impact of burning fossil fuels. However, the injection of CO2 into the subsurface shifts the chemical equilibrium between the mineral assemblage and the pore fluid. This shift will situationally facilitate dissolution and reprecipitation of mineral phases, in particular intergranular cements, and can potentially affect the long term mechanical stability of the host formation. The study of these coupled chemical-mechanical reservoir rock responses can help identify and control unexpected emergent behavior associated with geological CO2 storage.Experiments show that micro-mechanical methods are useful in capturing a variety of mechanical parameters, including Young's modulus, hardness and fracture toughness. In particular, micro-mechanical measurements are well-suited for examining thin altered layers on the surfaces of rock specimens, as well as capturing variability on the scale of lithofacies. We performed indentation and scratching tests on sandstone and siltstone rocks altered in natural CO2-brine environments, as well as on analogous samples altered under high pressure, temperature, and dissolved CO2 conditions in a controlled laboratory experiment. We performed geochemical modeling to support the experimental observations, in particular to gain the insight into mineral dissolution/precipitation as a result of the rock-water-CO2reactions. The comparison of scratch measurements performed on specimens both unaltered and altered by CO2 over geologic time scales results in statistically different values for fracture toughness and scratch hardness, indicating that long term exposure to CO2 caused mechanical degradation of the reservoir rock. Geochemical modeling indicates that major geochemical change caused by CO2 invasion of Entrada sandstone is dissolution of hematite cement, and its replacement with siderite and dolomite during the alteration process.

  20. Cat-Scratch Disease

    MedlinePlus

    ... Chickens in the City Diseases Cat-Scratch Disease E. coli Infection Ringworm Salmonella Infection Specific Groups & Settings Public Settings Organ Transplant Patients Infants and Young ... Dominguez KL, Hazra R, Handelsman E, et al. Guidelines for the prevention and treatment ...

  1. Influence of Soft Drinks with Low pH on Different Ni-Ti Orthodontic Archwire Surface Patterns

    NASA Astrophysics Data System (ADS)

    Abalos, C.; Paul, A.; Mendoza, A.; Solano, E.; Palazon, C.; Gil, F. J.

    2013-03-01

    The aim of this study was to determine the influence of soft drinks on the surface of Ni-Ti archwires and their corrosion behavior. Archwires with different patterns (smooth, scratch, dimple, and crack) were selected and characterized by scanning electron microscopy and laser confocal microscopy. Immersion tests were performed in artificial saliva (pH 6.7) with a soft drink with a pH of 2.5 for 28 days. The results showed an increase in the surface defects and/or roughness of the dimple, crack and scratch patterns with the immersion times, and a decrease in corrosion resistance. A relationship between the surface pattern and the extent of the corrosion in Ni-Ti archwires with soft drinks at low pH has been demonstrated. Pattern should be taken into account in future studies, and manufacturing processes that produce surface defects (especially cracks) should be avoided.

  2. Friction Anisotropy with Respect to Topographic Orientation

    PubMed Central

    Yu, Chengjiao; Wang, Q. Jane

    2012-01-01

    Friction characteristics with respect to surface topographic orientation were investigated using surfaces of different materials and fabricated with grooves of different scales. Scratching friction tests were conducted using a nano-indentation-scratching system with the tip motion parallel or perpendicular to the groove orientation. Similar friction anisotropy trends were observed for all the surfaces studied, which are (1) under a light load and for surfaces with narrow grooves, the tip motion parallel to the grooves offers higher friction coefficients than does that perpendicular to them, (2) otherwise, equal or lower friction coefficients are found under this motion. The influences of groove size relative to the diameter of the mating tip (as a representative asperity), surface contact stiffness, contact area, and the characteristic stiction length are discussed. The appearance of this friction anisotropy is independent of material; however, the boundary and the point of trend transition depend on material properties. PMID:23248751

  3. Nanoscale deformation and friction characteristics of atomically thin WSe2 and heterostructure using nanoscratch and Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Manimunda, P.; Nakanishi, Y.; Jaques, Y. M.; Susarla, S.; Woellner, C. F.; Bhowmick, S.; Asif, S. A. S.; Galvão, D. S.; Tiwary, C. S.; Ajayan, P. M.

    2017-12-01

    2D transition metals di-selenides are attracting a lot of attention due to their interesting optical, chemical and electronics properties. Here, the deformation characteristics of monolayer, multi- layer WSe2 and its heterostructure with MoSe2 were investigated using a new technique that combines nanoscratch and Raman spectroscopy. The 2D monolayer WSe2 showed anisotropy in deformation. Effect of number of WSe2 layers on friction characteristics were explored in detail. Experimental observations were further supported by MD simulations. Raman spectra recorded from the scratched regions showed strain induced degeneracy splitting. Further nano-scale scratch tests were extended to MoSe2-WSe2 lateral heterostructures. Effect of deformation on lateral hetero junctions were further analysed using PL and Raman spectroscopy. This new technique is completely general and can be applied to study other 2D materials.

  4. Mechanical comparison of a polymer nanocomposite to a ceramic thin-film anti-reflective filter.

    PubMed

    Druffel, Thad; Geng, Kebin; Grulke, Eric

    2006-07-28

    Thin-film filters on optical components have been in use for decades and, for those industries utilizing a polymer substrate, the mismatch in mechanical behaviour has caused problems. Surface damage including scratches and cracks induces haze on the optical filter, reducing the transmission of the optical article. An in-mold anti-reflective (AR) filter incorporating 1/4-wavelength thin films based on a polymer nanocomposite is outlined here and compared with a traditional vacuum deposition AR coating. Nanoindentation and nanoscratch techniques are used to evaluate the mechanical properties of the thin films. Scanning electron microscopy (SEM) images of the resulting indentations and scratches are then compared to the force deflection curves to further explain the phenomena. The traditional coatings fractured by brittle mechanisms during testing, increasing the area of failure, whereas the polymer nanocomposite gave ductile failure with less surface damage.

  5. Effect of local endometrial injury on pregnancy outcomes in ovum donation cycles.

    PubMed

    Dain, Lena; Ojha, Kamal; Bider, David; Levron, Jacob; Zinchenko, Viktor; Walster, Sharon; Dirnfeld, Martha

    2014-10-01

    To evaluate the effect of local endometrial injury (LEI) on clinical outcomes in ovum donation recipients. Retrospective cohort analysis of ovum donation cycles conducted from 2005 to 2012. Two private IVF centers. Total 737 ovum donation cycles. LEI by endometrial "scratch" with the use of a Pipelle catheter. Clinical pregnancy and live birth rates. No statistically significant differences were found in clinical pregnancy rates and live birth rates in cycles subjected to LEI compared with those without. Combination of LEI with fibroid uterus resulted with significantly higher clinical pregnancy rates compared with LEI in normal uterine anatomy. This is the first study done in ovum recipients who underwent LEI by a "scratch" procedure after failed implantation. Unlike most previous reports, which found improved pregnancy rates with the use of "scratch effect" or "minor endometrial injury" after repeated implantation failures in standard IVF with own eggs, we did not find any changes in implantation rates in a population of egg recipients following this procedure. In view of a possible positive effect of LEI in cycles with a previous four or more failures, prospective randomized controlled studies are warranted to better define the target population who may benefit from this intervention. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  6. Physical and Neuropsychiatric Trauma-Wound Healing and Tissue Preservation

    DTIC Science & Technology

    2008-10-01

    Scratch No Scratch+ LOS 8 Scratch + LOS POS Treatment Paradigm 1% both 1% HS 1%FBS Note that the media which showed the least LDH reactivity...shown in Figure 3. Figure 2 Jarvis, Gary PhD W81XWH-05-2-0094 6 Effect of LOS 89i on Cell Death 0.00 0.50 1.00 1.50 2.00 2.50...e le a se 1% FBS 1% FBS & LOS Figure 3 demonstrates that treatment of C6 glioma cells with 89I LPS results in protection of the cells

  7. Wear at the Implant-Abutment Interface of Zirconia Abutments Manufactured by Three CAD/CAM Systems.

    PubMed

    Pinheiro Tannure, Ana Luiza; Cunha, Alfredo Gonçalves; Borges Junior, Luiz Antônio; da Silva Concílio, Laís Regiane; Claro Neves, Ana Christina

    To evaluate the changes in the external-hexagon surface of the titanium (Ti) implant before and after mechanical cycling, when coupled with zirconia (Zr) abutments (A) manufactured by three computer-aided design/computer-aided manufacturing (CAD/CAM) systems (Neodent Digital, Zirkonzahn, and AmannGirrbach) and the ZrTi abutment manufactured by Neodent. Four groups were formed (n = 6): titanium implant with Zr AmannGirrbach abutment (AZrAG), with Zr Zirkonzahn abutment (AZrZ), with Zr Neodent abutment (AZrN), and with Zr abutment with infrastructure in Ti Neodent (AZrTiN). Standardized abutments were made from three identical abutments milled in wax. Images of the surface of each side of the hexagons of the implant were obtained by scanning electron microscopy, before and after mechanical cycling, to evaluate the parameters: (1) scratches in the hexagon face; (2) hexagon superior shoulder kneading; (3) hexagon shoulder wear; (4) alterations on the hexagon base; and (5) scratches on the hexagon top. The abutments were coupled with the implants, and Cr-Co crowns were cemented. The implant/abutment/crown assemblies were submitted to mechanical cycling (400 N, 8.0 Hz) for 1 million cycles. The observed changes were classified as follows: absence (0), mild (1), moderate (2), and severe (3). The results were analyzed using the Mann-Whitney, Kruskal-Wallis, and Dunn tests (P < .05). For parameter 1, a significant difference (P = .008) was observed between AZrZ and AZrAG, with more scratches in AZrZ; and between AZrN and AZrTiN (P = .006), with more scratches in AZrN. For parameter 2, a significant difference (P < .05) was observed between AZrZ and AZrAG and between AZrZ and AZrN, with greater kneading in AZrZ; among AZrN and AZrTiN, there was no significant difference (P = .103). For parameter 3, a significant difference (P < .05) was observed between AZrZ and the other groups of Zr, with more wear in AZrZ; between AZrN and AZrTiN, there was no significant difference (P = .107). For parameter 4, a significant difference (P < .05) was observed between AZrZ and AZrN, with more scratches in AZrZ; a significant difference (P = .002) was also observed between AZrN and AZrTiN, with more scratches in AZrN. For parameter 5, a significant difference (P < .05) was observed between AZrZ and AZrAG and between AZrZ and AZrN, with the fewest scratches in AZrZ; a significant difference (P = .006) was also observed between AZrN and AZrTiN, with more alterations in AZrN. Considering all the alterations, the AZrZ group showed more surface alteration, 1.74 (0.99); followed by AZrN, 1.43 (0.92); AZrAG, 1.32 (0.96); and AZrTiN, 0.88 (0.94). Among the Neodent abutments, the AZrN group had shown more surface alterations. Among the Zr groups, AZrZ samples had shown the most altered surfaces, suggesting that alterations on the implant/Zr abutment hexagon surfaces are related to the abutment milled hexagon shape.

  8. Cell migration, viability and tissue reaction of calcium hypochlorite based-solutions irrigants: An in vitro and in vivo study.

    PubMed

    Blattes, Gabriela Bess Ferraz; Mestieri, Leticia Boldrin; Böttcher, Daiana Elisabeth; Fossati, Anna Cristina Medeiros; Montagner, Francisco; Grecca, Fabiana Soares

    2017-01-01

    This study aimed to analyze in vitro cytotoxicity to cultured 3T3 fibroblasts and in vivo inflammatory reaction in rats by calcium hypochlorite (Ca(OCl) 2 ) solutions compared with sodium hypochlorite (NaOCl) solutions. Cultured 3T3 fibroblasts were exposed to different concentrations of (Ca(OCl) 2 ) and NaOCl solutions, and a scratch assay was performed. The viability rate was analyzed with trypan blue assay. Both solutions of 1% and 2.5% concentrations were injected into the subcutaneous tissue of 18 male Wistar rats aged 18 weeks. The inflammatory tissue reaction was evaluated at 2h, 24h, and 14days after the injections. The samples were qualitatively analyzed using a light microscope. Statistical analysis was performed with ANOVA and Tukey post hoc tests for in vitro assays and Kruskal-Wallis and Dunn post hoc tests for in vivo assays (α=0.05). In the scratch assay, Ca(OCl) 2 showed no significant difference compared with the control group (culture medium) at 24h (p<0.05). Solutions of 0.0075% and 0.005% NaOCl and Ca(OCl) 2 concentrations presented similar results compared with those in the positive control group (hydrogen peroxide) (p>0.05) in the trypan blue assay. In the in vivo assay, 1% Ca(OCl) 2 group showed a significant decrease in neutrophils at 2h and 24h (p=0.041) and 2h and 14days (p=0.017). There was no statistically significant difference for lymphocyte/plasmocyte and macrophage counts among the different concentration groups. Ca(OCl) 2 showed favorable results of viability and induced a low-level inflammatory response. Ca(OCl) 2 presented acceptable cytotoxicity and biocompatibility as an irrigant solution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Benefits of utilizing CellProfiler as a characterization tool for U–10Mo nuclear fuel

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

    Collette, R.; Douglas, J.; Patterson, L.

    2015-07-15

    Automated image processing techniques have the potential to aid in the performance evaluation of nuclear fuels by eliminating judgment calls that may vary from person-to-person or sample-to-sample. Analysis of in-core fuel performance is required for design and safety evaluations related to almost every aspect of the nuclear fuel cycle. This study presents a methodology for assessing the quality of uranium–molybdenum fuel images and describes image analysis routines designed for the characterization of several important microstructural properties. The analyses are performed in CellProfiler, an open-source program designed to enable biologists without training in computer vision or programming to automatically extract cellularmore » measurements from large image sets. The quality metric scores an image based on three parameters: the illumination gradient across the image, the overall focus of the image, and the fraction of the image that contains scratches. The metric presents the user with the ability to ‘pass’ or ‘fail’ an image based on a reproducible quality score. Passable images may then be characterized through a separate CellProfiler pipeline, which enlists a variety of common image analysis techniques. The results demonstrate the ability to reliably pass or fail images based on the illumination, focus, and scratch fraction of the image, followed by automatic extraction of morphological data with respect to fission gas voids, interaction layers, and grain boundaries. - Graphical abstract: Display Omitted - Highlights: • A technique is developed to score U–10Mo FIB-SEM image quality using CellProfiler. • The pass/fail metric is based on image illumination, focus, and area scratched. • Automated image analysis is performed in pipeline fashion to characterize images. • Fission gas void, interaction layer, and grain boundary coverage data is extracted. • Preliminary characterization results demonstrate consistency of the algorithm.« less

  10. Cat-Scratch Disease

    MedlinePlus

    ... Resources Centers for Disease Control and Prevention, Healthy Pets Healthy People, Cat-Scratch Disease Last Updated: May 19, 2017 This article was contributed by: familydoctor.org editorial staff Categories: Family Health, Pets and Animals, Prevention and Wellness, Staying HealthyTags: Bartonella ...

  11. An Experimental Itch Model in Monkeys

    PubMed Central

    Ko, M. C. Holden; Naughton, Norah N.

    2007-01-01

    Background The most common side effect of spinal opioid administration is pruritus, which has been treated with a variety of agents with variable success. Currently, there are few animal models developed to study this side effect. The aim of this study was to establish a nonhuman primate model to pharmacologically characterize the effects of intrathecal administration of morphine. Methods Eight adult rhesus monkeys were used. Scratching responses were videotaped and counted by observers who were blinded to experimental conditions. Antinociception was measured by a warm-water (50°C) tail-withdrawal assay. The dose-response of intrathecal morphine (1-320 μg) for both scratching and antinociception in all subjects was established. An opioid antagonist, nalmefene, was administered either intravenously or subcutaneously to assess its efficacy against intrathecal morphine. Results Intrathecal morphine (1-32 μg) increased scratching in a dose-dependent manner. Higher doses of intrathecal morphine (10-100 μg) produced thermal antinociception in a dose-dependent manner. On the other hand, nalmefene (10-32 μg/kg intravenously) attenuated maximum scratching responses among subjects. Pretreatment with nalmefene (32μg/kg subcutaneously) produced approximately 10-fold rightward shifts of intrathecal morphine dose-response curves for both behavioral effects. Conclusions These data indicate that intrathecal morphine-induced scratching and antinociception are mediated by opioid receptors. The magnitude of nalmefene antagonism of intrathecal morphine is consistent with μ opioid receptor mediation. This experimental itch model is useful for evaluating different agents that may suppress scratching without interfering with antinociception. It may also facilitate the clarification of mechanisms underlying these phenomena. PMID:10719958

  12. Deformation mechanisms in advanced structural ceramics due to indentation and scratch processes

    NASA Astrophysics Data System (ADS)

    Ghosh, Dipankar

    Plasma pressure compaction technique was used to develop boron carbide (B4C) and zirconium diboride-silicon carbide (ZrB2-SiC) composite. B4C ceramics are extensively used as body armor in military and civilian applications, and ZrB2-SiC composite has been recognized as a potential candidate for high-temperature aerospace applications. In this dissertation, processing parameters, quasistatic and high-strain rate mechanical response, and fundamental deformation mechanisms of these materials have been investigated. In the case of B4C, the rate sensitivity of indentation hardness was determined using a dynamic indentation hardness tester that can deliver loads in 100 micros. By comparing dynamic hardness with the static hardness, it was found that B4C exhibits a lower hardness at high-strain rate, contrary to known behavior in many structural ceramics. However, these results are consistent with the ballistic testing of B4C armors as reported in recent literature. This behavior was further investigated using a series of spectroscopic techniques such as visible and UV micro-Raman, photoluminescence and infrared. These studies not only confirmed that structural transformation occurred during indentation experiments similar to that in ballistic testing of B4C but also suggested a greater degree of structural changes under dynamic loading compared to static loading. Due to the potential application as external heat shields in supersonic vehicles, scratch studies were conducted on the ZrB2-SiC composite. These studies revealed metal-like slip-line patterns which are indeed an unusual in brittle solids at room-temperature. Utilizing classical stress field solutions under combined normal and tangential loads, a rationale was developed for understanding the formation of scratch-induced deformation features. Also, an analytical framework was developed, combining the concept of 'blister field' and the 'secular equation' relating Raman peaks to strain, to measure scratch-induced residual stress employing micro-Raman spectroscopy. Transmission electron microscopic investigations confirmed the existence of dislocations within the ZrB2 phase. It has been argued here that readily detectable slipline patterns are reflection of metallicity in chemical bonding present in ZrB2 ceramics which has also been suggested in recent literature from chemical bonding and electronic structure investigations.

  13. [Role of connective tissue growth factor (CTGF) in proliferation and migration of pancreatic cancer cells].

    PubMed

    Bai, Yu-chun; Kang, Quan; Luo, Qing; Wu, Dao-qi; Ye, Wei-xia; Lin, Xue-mei; Zhao, Yong

    2011-10-01

    To explore the expression of connective tissue growth factor (CTGF) in pancreatic cancer and its influence on the proliferation and migration of cancer cells. The expression of CTGF in pancreatic cell line PANC-1 cells was analyzed by real-time PCR and in pancreatic carcinoma (50 cases) tissues by immunohistochemistry. The ability of proliferation and migration in vitro of PANC-1 cells was tested by MTT assay, scratch test and Boyden chamber test after the CTGF gene was overexpressed by Ad5-CTGF or silenced with Ad5-siCTGF transfection. CTGF was overexpressed in both pancreatic cancer cells and tissues. Overxpression of CTGF leads to increased proliferation and migration of PANC-1 cells. The CTGF-transfected PANC-1 cells showed apparent stronger proliferation ability and scratch-repair ability than that of empty vector controls. The results of Boyden chamber test showed that there were 34 cells/field (200× magnificantion) of the CTGF-transfected overexpressing cells, much more than the 11 cells/field of the empty vector control cells; and 6 cells/microscopic field of the Ad5-siCTGF-transfected silenced cells, much less than the 15 cells/field of the control cells. CTGF is overexpressed in both pancreatic cancer cells in vitro and in vivo, indicating that it may play an important role in the cell proliferation and migration in pancreatic cancer.

  14. Application of EIS and SECM Studies for Investigation of Anticorrosion Properties of Epoxy Coatings Containing Zinc Oxide Nanoparticles on Mild Steel in 3.5% NaCl Solution

    NASA Astrophysics Data System (ADS)

    Raj, X. Joseph

    2017-07-01

    The effect of corrosion protection performance of epoxy coatings containing ZnO nanoparticle on mild steel in 3.5% NaCl solution was analyzed using scanning electrochemical microscopy and electrochemical impedance spectroscopy (EIS). Line profile and topographic image analysis were measured by applying -0.70 and +0.60 V as the tip potential for the cathodic and anodic reactions, respectively. The tip current at -0.70 V for the epoxy-coated sample with ZnO nanoparticles decreased rapidly, which is due to cathodic reduction in dissolved oxygen. The EIS measurements were taken in 3.5% NaCl after wet and dry cyclic corrosion test. The increase in the film resistance ( R f) and charge transfer resistance ( R ct) values was confirmed by the addition of ZnO nanoparticles in the epoxy coating. SEM/EDX analysis showed that complex oxide layer of zinc was enriched in corrosion products at a scratched area of the coated steel after corrosion testing. FIB-TEM analysis confirmed the presence of the nanoscale complex oxide layer of Zn in the rust of the steel that had a beneficial effect on the corrosion resistance of coated steel by forming protective corrosion products in the wet/dry cyclic test.

  15. IL-6 as a corneal wound healing mediator in an in vitro scratch assay.

    PubMed

    Arranz-Valsero, Isabel; Soriano-Romaní, Laura; García-Posadas, Laura; López-García, Antonio; Diebold, Yolanda

    2014-08-01

    Corneal healing process under inflammatory conditions is not fully understood. We aimed at determining the effect of an inflammatory (presence of IL-6) or anti-inflammatory (presence of IL-10) environment and a mixture of both in the expression of IL-6 signaling pathway mediators, and on corneal wound healing in an in vitro scratch assay. For that purpose, human corneal epithelial cells were cultured until confluence. The effect of IL-6 (10 ng/ml), IL-10 (20 ng/ml) or IL-6 + IL-10 exposure on the expression of IL-6R, gp130, and STAT3 was determined by Western blotting and quantitative PCR, at different time points. The monolayer was mechanically wounded using a sterile 10 μl pipette tip. Wound healing rate in the presence or absence of these cytokines was measured immediately after cytokine exposure and after 4, 8, and 24 h. The effect of mitomycin C on wound healing rate, in control and IL-6-stimulated cells, was also evaluated. Detection of proliferative cells was performed with an EdU imaging kit. For the visualization of migrating cells, cold methanol-fixed cells were incubated with an α-actinin antibody. For the statistical analysis a two-factor design of experiment method was applied. Levene test was used to contrast equality of variances. If variances were equal, ANOVA was performed to test the equality of means. If variances were not equal, a Mood's median test was performed. We observed that IL-6 and IL-10 stimulation, and their combination, increased gp130 production at different time points. STAT3 production was increased in IL-6-stimulated cells, at 72 h. An increase in pSTAT3 production was found in IL-6- and IL-10-stimulated cells, that was sustained in time in IL-6 + IL-10 co-stimulated cultures. Scraped areas had an initial width of 570.57 ± 75.82 μm. In IL-6-exposed cells wound healing closure was faster than in control cells or IL-10-exposed cells. After 8 h, wound width in IL-10-exposed cells, was also significantly smaller than that of control cells. Cells exposed to IL-6 + IL-10 had the slowest wound healing rate, similar to control cells. Wounds were closed after 24 h regardless the experimental condition. Mitomycin C exposure increased the wound closure rate in every experimental condition. No significant differences in the percentage of proliferative cells at the edge of the scratch and in distant areas of the monolayer were found. At the edge of the scratch, some actin filaments of non-proliferative cells were directed through the cell-free area, independently of the stimulating condition. In conclusion, the presence of IL-10 and, most importantly, of IL-6, increased the wound healing rate in an in vitro corneal wound healing model. The combination of both cytokines did not have a synergistic action in wound healing. In our model, wound closure was the result of the combination of cell proliferation and cell migration. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Head-scratching method of the Swainson's warbler

    USGS Publications Warehouse

    Meanley, Brooke

    1970-01-01

    Ficken and Ficken (Auk, 85: 136, 1968) suggest that the "Head-scratching method may prove a valuable addition to the set of complex characters that can be used in defining genera," and that field observers should continue to fill gaps in our knowledge of this behavior. In the course of a series of observations of Swainson's Warblers (Limnothlypis swainsonii) in the Dismal Swamp, Virginia, I saw head-scratching in three individuals, four times in one, three in another, and once in the third. All three birds used the direct method, bringing the foot forward and under the wing.

  17. A pediatric case with peripheral facial nerve palsy caused by a granulomatous lesion associated with cat scratch disease.

    PubMed

    Nakamura, Chizuko; Inaba, Yuji; Tsukahara, Keiko; Mochizuki, Mie; Sawanobori, Emi; Nakazawa, Yozo; Aoyama, Kouki

    2018-02-01

    Cat scratch disease is a common infectious disorder caused by Bartonella henselae that is transmitted primarily by kittens. It typically exhibits a benign and self-limiting course of subacute regional lymphadenopathy and fever lasting two to eight weeks. The most severe complication of cat scratch disease is involvement of the nervous system, such as encephalitis, meningitis, and polyneuritis. Peripheral facial nerve palsy associated with Bartonella infection is rare; few reported pediatric and adult cases exist and the precise pathogenesis is unknown. A previously healthy 7-year-old boy presented with fever, cervical lymphadenopathy, and peripheral facial nerve palsy associated with serologically confirmed cat scratch disease. The stapedius muscle reflex was absent on the left side and brain magnetic resonance imaging revealed a mass lesion at the left internal auditory meatus. The patient's symptoms and imaging findings were gradually resolved after the antibiotics and corticosteroids treatment. The suspected granulomatous lesion was considered to have resulted from the host's immune reaction to Bartonella infection and impaired the facial nerve. This is the first case report providing direct evidence of peripheral facial nerve palsy caused by a suspected granulomatous lesion associated with cat scratch disease and its treatment course. Copyright © 2017. Published by Elsevier B.V.

  18. Development of resistance to serotonin-induced itch in bile duct ligated mice.

    PubMed

    Ostadhadi, Sattar; Haddadi, Nazgol-Sadat; Foroutan, Arash; Azimi, Ehsan; Elmariah, Sarina; Dehpour, Ahmad-Reza

    2017-06-01

    Cholestatic itch can be severe and significantly impair the quality of life of patients. The serotonin system is implicated in cholestatic itch; however, the pruritogenic properties of serotonin have not been evaluated in cholestatic mice. Here, we investigated the serotonin-induced itch in cholestatic mice which was induced by bile duct ligation (BDL). Serotonin, sertraline or saline were administered intradermally to the rostral back area in BDL and sham operated (SHAM) mice, and the scratching behaviour was videotaped for 1 hour. Bile duct ligated mice had significantly increased scratching responses to saline injection on the seventh day after surgery. Additionally, serotonin or sertraline significantly induced scratching behaviour in BDL mice compared to saline at day 7 after surgery, while it did not induce itch at day 5. The scratching behaviour induced by serotonin or sertraline was significantly less in BDL mice compared to SHAM mice. Likewise, the locomotor activity of BDL or SHAM mice was not significantly different from unoperated (UNOP) mice on the fifth and seventh day, suggesting that the scratching behaviour was not affected by motor dysfunctions. Our data suggest that despite the potentiation of evoked itch, a resistance to serotonin-induced itch is developed in cholestatic mice. © 2017 John Wiley & Sons Australia, Ltd.

  19. Crucial role of vinexin for keratinocyte migration in vitro and epidermal wound healing in vivo

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

    Kioka, Noriyuki, E-mail: nkioka@kais.kyoto-u.ac.jp; Ito, Takuya; Yamashita, Hiroshi

    2010-06-10

    In the process of tissue injury and repair, epithelial cells rapidly migrate and form epithelial sheets. Vinexin is a cytoplasmic molecule of the integrin-containing cell adhesion complex localized at focal contacts in vitro. Here, we investigated the roles of vinexin in keratinocyte migration in vitro and wound healing in vivo. Vinexin knockdown using siRNA delayed migration of both HaCaT human keratinocytes and A431 epidermoid carcinoma cells in scratch assay but did not affect cell proliferation. Induction of cell migration by scratching the confluent monolayer culture of these cells activated both EGFR and ERK, and their inhibitors AG1478 and U0126 substantiallymore » suppressed scratch-induced keratinocyte migration. Vinexin knockdown in these cells inhibited the scratch-induced activation of EGFR, but not that of ERK, suggesting that vinexin promotes cell migration via activation of EGFR. We further generated vinexin (-/-) mice and isolated their keratinocytes. They similarly showed slow migration in scratch assay. Furthermore, vinexin (-/-) mice exhibited a delay in cutaneous wound healing in both the back skin and tail without affecting the proliferation of keratinocytes. Together, these results strongly suggest a crucial role of vinexin in keratinocyte migration in vitro and cutaneous wound healing in vivo.« less

  20. Evaluation of the LiveWell@School Food Initiative Shows Increases in Scratch Cooking and Improvement in Nutritional Content.

    PubMed

    Schober, Daniel J; Carpenter, Leah; Currie, Venita; Yaroch, Amy L

    2016-08-01

    The purpose of this evaluation was to examine the effects of the LiveWell@School Food Initiative (LW@SFI), a Colorado-based childhood obesity prevention program that partners with school districts to enable them to serve more scratch cooked foods through culinary training, action planning, and equipment grants. This evaluation used a quasi-experimental design that examined menu cycles prior to entering the LW@SFI and approximately 1 year later. A review of school menus with food service directors from 9 Colorado school districts was conducted. Data show that districts changed an average of 17.4 entrées and 19.7 side dishes over the course of the year. Changes to serving scratch cooked foods were highest for sauces (an increase of 40.5%). No districts were cooking beans/legumes from scratch during baseline or at follow-up. Across the 9 districts, 7 observed statistically significant pre-post reductions in sodium, 4 in fat, 5 in saturated fat, and 3 in calories. Within a year of implementing the LW@SFI, school districts increased the proportion of fresh, scratch cooked foods they offered and this was associated with some decreases in calories, fat, saturated fat, and sodium, contributing to healthier school food environments. © 2016, American School Health Association.

  1. Differences Between Men and Women in Chronic Scratching: A Psychodermatologic Study in Lichen Simplex Chronicus.

    PubMed

    Martín-Brufau, R; Suso-Ribera, C; Brufau Redondo, C; Corbalán Berná, J

    2017-05-01

    Chronic scratching is common to many skin disorders. Being a female and presenting a high level of psychopathology are risk factors for chronic scratching. Yet, it is unclear why. Certain personality characteristics that are more prevalent in women are also known to influence emotional states (i.e. emotional tension). The present study aims to explore whether these personality styles might help understand why gender and emotional distress are associated with scratching. We compared the personality patterns of 103 patients (69.9% women) diagnosed with Lichen Simplex Chronicus, against a sample of healthy individuals. Significant differences were found in the personality styles of men and women with LSC. Women were more pessimistic, oriented to fulfil the needs of others, traditional, insecure, submissive, and reserved, with moderate (d=.43) to strong (d=.96) size effects ranges. Some of these differences, such as in traditionalism, dutifulness, other-orientation, and pessimism, were also observed when compared with healthy men and women, with small (d=.03) to moderate (d=.47) size effects ranges. These psychological factors may help explain the mechanisms underlying gender differences in chronic scratching, at least in Lichen Simplex Chronicus. The findings might open new avenues for research and treatment. Copyright © 2017 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

  2. When play is a family business: adult play, hierarchy, and possible stress reduction in common marmosets.

    PubMed

    Norscia, Ivan; Palagi, Elisabetta

    2011-04-01

    Easy to recognize but not easy to define, animal play is a baffling behavior because it has no obvious immediate benefits for the performers. However, the absence of immediate advantages, if true, would leave adult play (costly but maintained by evolution, spanning lemurs to Homo sapiens) unexplained. Although a commonly held view maintains that play is limited by stress, an emergent hypothesis states that play can regulate stress in the short term. Here we explored this hypothesis in a captive family group of New World monkeys, Callithrix jacchus (common marmoset). We observed six subjects and gathered data on aggressive, play, and scratching behavior via focal (6 h/individual) and all occurrences sampling (115 h). We found that play levels were highest during pre-feeding, the period of maximum anxiety due to the forthcoming competition over food. Scratching (the most reliable indicator of stress in primates) and play showed opposite trends along hierarchy, with dominants scratching more and playing less than subordinates. Finally, scratching decreased after play, whereas play appeared to be unrelated to previous scratching events, symptoms of a potential stressful state. In conclusion, both play timing and hierarchical distribution indicate that play limits stress, more than vice versa, at least in the short term.

  3. Properties of Lightning Strike Protection Coatings

    NASA Astrophysics Data System (ADS)

    Gagne, Martin

    Composite materials are being increasingly used by many industries. In the case of aerospace companies, those materials are installed on their aircraft to save weight, and thus, fuel costs. These aircraft are lighter, but the loss of electrical conductivity makes aircraft vulnerable to lightning strikes, which hit commercial aircrafts on average once per year. This makes lightning strike protection very important, and while current metallic expanded copper foils offer good protection, they increase the weight of composites. Therefore, under the CRIAQ COMP-502 project, a team of industrial partners and academic researchers are investigating new conductive coatings with the following characteristics: High electromagnetic protection, high mechanical resistance, good environmental protection, manufacturability and moderate cost. The main objectives of this thesis, as part of this project, was to determine the main characteristics, such as electrical and tribomechanical properties, of conductive coatings on composite panels. Their properties were also to be tested after destructive tests such as current injection and environmental testing. Bombardier Aerospace provided the substrate, a composite of carbon fiber reinforced epoxy matrix, and the current commercial product, a surfacing film that includes an expanded copper foil used to compare with the other coatings. The conductive coatings fabricated by the students are: silver nanoparticles inside a binding matrix (PEDOT:PSS or a mix of Epoxy and PEDOT:PSS), silvered carbon nanofibers embedded in the surfacing film, cold sprayed tin, graphene oxide functionalized with silver nanowires, and electroless plated silver. Additionally as part of the project and thesis, magnetron sputtered aluminum coated samples were fabricated. There are three main types of tests to characterize the conductive coatings: electrical, mechanical and environmental. Electrical tests consist of finding the sheet resistance and specific resistivity of conductive coatings. Mechanical tests include adhesion, scratch, hardness and Young's modulus of the coatings. The environmental tests are temperature cycling and salt spray cycling. These basic characteristics were investigated first, but further tests also combine the categories, such as electrical tests before, during and after environmental tests, and the effects on the sample's mechanical properties after high electrical current injections. The electrical properties of the conductive coatings have improved and are very close to that of current expanded metallic foil or within an order of magnitude. The mechanical properties of most of these coatings are also good. They exhibit good adhesion, hardness, and no significant loss of flexion properties after current injections. The environmental tests are more mitigated, with some conductive coatings losing their surface conductivity, others having a small increase in specific resistivity, and some were simply unaffected. Tests such as thermogravimetric analysis, scanning electron microscope analysis of scratch tests, and optical microscope observations are included to provide additional analysis of the results of the conductive coatings. The conductive coatings were characterized and tested as part of the CRIAQ project. Lightning strike tests are required to gather further information on these conductive coatings. The main application for these coatings is for lightning strike protection of aircraft, but they can also be used for ground based lightning strike protection and general electromagnetic shielding.

  4. Inferring pterosaur diets through quantitative 3D textural analysis of tooth microwear in extant analogues

    NASA Astrophysics Data System (ADS)

    Bestwick, Jordan; Unwin, David; Butler, Richard; Henderson, Don; Purnell, Mark

    2017-04-01

    Pterosaurs (Pterosauria) were a successful group of Mesozoic flying reptiles. For 150 million years they were integral components of terrestrial and coastal ecosystems, yet their feeding ecology remains poorly constrained. Postulated pterosaur diets include insectivory, piscivory and/or carnivory, but many dietary hypotheses are speculative and/or based on little evidence, highlighting the need for alternative approaches to provide robust data. One method involves quantitative analysis of the micron-scale 3D textures of worn pterosaur tooth surfaces - dental microwear texture analysis. Microwear is produced as scratches and chips generated by food items create characteristic tooth surface textures. Microwear analysis has never been applied to pterosaurs, but we might expect microwear textures to differ between pterosaurs with different diets. An important step in investigating pterosaur microwear is to examine microwear from extant organisms with known diets to provide a comparative data set. This has been achieved through analysis of non-occlusal microwear textures in extant bats, crocodilians and monitor lizards, clades within which species exhibit insectivorous, piscivorous and carnivorous diets. The results - the first test of the hypothesis that non-occlusal microwear textures in these extant clades vary with diet - provide the context for the first robust quantitative tests of pterosaur diets.

  5. Evaluation of the adhesion on the nano-scaled polymeric film systems.

    PubMed

    Park, Tae Sung; Park, Ik Keun; Yoshida, Sanichiro

    2017-04-01

    We applied scanning acoustic microscopy known as the V(z) curve technique to photoresist thin-film systems for the evaluation of the adhesive strength at the film-substrate interface. Through the measurement of the SAW (Surface Acoustic Wave) velocity, the V(z) curve analysis allows us to quantify the stiffness of the film-substrate interface. In addition, we conducted a nano-scratch test to quantify the ultimate strength of the adhesion through the evaluation of the critical load. To vary the adhesive conditions, we prepared thin-film specimens with three different types of pre-coating surface treatments, i.e., oxygen-plasma bombardment, HMDS (Hexametyldisilazane) treatment and untreated. The magnitudes of the quantified stiffness and ultimate strength are found consistent with each other for all the specimens tested, indicating that the pre-coating surface treatment can strengthen both the stiffness and ultimate strength of the adhesion. The results of this study demonstrate the usefulness of the V(Z) analysis as a nondestructive method to evaluate the adhesion strength of nano-structured thin-film systems. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Study of abrasive wear rate of silicon using n-alcohols

    NASA Technical Reports Server (NTRS)

    Danyluk, S.

    1982-01-01

    The work carried out at the University of Illinois at Chicago for the Flat-Plate Solar Array Project under contract No. 956053 is summarized. The abrasion wear rate of silicon in a number of fluid environments and the parameters that influence the surface mechanical properties of silicon were determined. Three tests were carried out in this study: circular and linear multiple-scratch test, microhardness test and a three-point bend test. The pertinent parameters such as effect of surface orientation, dopant and fluid properties were sorted. A brief review and critique of previous work is presented.

  7. Failure Analysis Study and Long-Term Reliability of Optical Assemblies with End-Face Damage

    NASA Technical Reports Server (NTRS)

    Kichak, Robert A.; Ott, Melanie N.; Leidecker, Henning W.; Chuska, Richard F.; Greenwell, Christopher J.

    2008-01-01

    In June 2005, the NESC received a multi-faceted request to determine the long term reliability of fiber optic termini on the ISS that exhibited flaws not manufactured to best workmanship practices. There was a lack of data related to fiber optic workmanship as it affects the long term reliability of optical fiber assemblies in a harsh environment. A fiber optic defect analysis was requested which would find and/or create various types of chips, spalls, scratches, etc., that were identified by the ISS personnel. Once the defects and causes were identified the next step would be to perform long term reliability testing of similar assemblies with similar defects. The goal of the defect analysis would be for the defects to be observed and documented for deterioration of fiber optic performance. Though this report mostly discusses what has been determined as evidence of poor manufacturing processes, it also concludes the majority of the damage could have been avoided with a rigorous process in place.

  8. GRAHAM NELSON AND ANDREW HANKS WITH BREADBOARD ENGINE PROJECT CO

    NASA Image and Video Library

    2016-09-14

    Graham Nelson, right, and Andrew Hanks examine a combustion chamber developed by engineers at NASA's Marshall Space Flight Center in Huntsville, Alabama, for an additively manufactured demonstration breadboard engine project. Nelson is project manager and Hanks is test lead for the project, in which engineers are designing components from scratch to be made entirely by 3-D printing.

  9. Development of an all-metal thick-film cost-effective metallization system for solar cells

    NASA Technical Reports Server (NTRS)

    Ross, B.

    1981-01-01

    Screened electrodes made from fluorocarbon activated copper paste and silver fluoride activated copper paste, tape adhesion and scratch tests were studied. Experiments were conducted with variations in past parameters, firing conditions, including gas ambients, furnace furniture, silicon surface and others. A liquid medium intended to provide transport during the carbon fluoride decomposition, is incorporated in the paste.

  10. Cedar pollen aggravates atopic dermatitis in childhood monozygotic twin patients with allergic rhino conjunctivitis.

    PubMed

    Murakami, Yukako; Matsui, Saki; Kijima, Akiko; Kitaba, Shun; Murota, Hiroyuki; Katayama, Ichiro

    2011-09-01

    We report a case of 7-year-old monozygotic twin patients with atopic dermatitis. The HLA haplotypes were HLA A2, A11, B27, B61, DR1, and DR4. Both serum IgE levels and cedar pollen radioallergosorbent test (RAST) scores were high in the twins (elder/younger sister: IgE: 5170/3980 IU/ml and Japansese cedar pollen: >100/64.0) in contrast to low mite and food RAST scores (Dermatophagoides Pterygonium; 0.59/0.4 and egg white 9.24/4.6). The patients showed positive immediate (20 min in both sisters) and delayed (24 hours in elder sister, 24, 48, 72 hours in younger sister) reactions to a scratch test with Japanese cedar pollen. Skin lesions on the face were aggravated and extended to the trunk and extremities during the Japanese cedar pollen season and gradually subsided in summer. Oral provocation with egg white or cow milk showed no exacerbations, and topical corticosteroid did not improve the eczema. In contrast, successful protection from severe scratching behaviors was achieved by use of topical anti-allergic eye drops and wearing nightgowns made by the mother.

  11. VESUVIO Data Analysis Goes MANTID

    NASA Astrophysics Data System (ADS)

    Jackson, S.; Krzystyniak, M.; Seel, A. G.; Gigg, M.; Richards, S. E.; Fernandez-Alonso, F.

    2014-12-01

    This paper describes ongoing efforts to implement the reduction and analysis of neutron Compton scattering data within the MANTID framework. Recently, extensive work has been carried out to integrate the bespoke data reduction and analysis routines written for VESUVIO with the MANTID framework. While the programs described in this document are designed to replicate the functionality of the Fortran and Genie routines already in use, most of them have been written from scratch and are not based on the original code base.

  12. Fitness testing as a discriminative tool for the diagnosis and monitoring of fibromyalgia.

    PubMed

    Aparicio, V A; Carbonell-Baeza, A; Ruiz, J R; Aranda, P; Tercedor, P; Delgado-Fernández, M; Ortega, F B

    2013-08-01

    We aimed to determine the ability of a set of physical fitness tests to discriminate between presence/absence of fibromyalgia (FM) and moderate/severe FM. The sample comprised 94 female FM patients (52 ± 8 years) and 66 healthy women (54 ± 6 years). We assessed physical fitness by means of the 30-s chair stand, handgrip strength, chair sit and reach, back scratch, blind flamingo, 8-feet up and go, and 6-min walking tests. Patients were classified as having moderate FM if the score in the Fibromyalgia Impact Questionnaire (FIQ) was <70 and as having severe FM if the FIQ was ≥70. FM patients and patients with severe FM performed worse in most of the fitness tests studied (P < 0.001). Except the back scratch test, all the tests were able to discriminate between presence and absence of FM [area under the curve (AUC) = 0.66 to 0.92; P ≤ 0.001], and four tests also discriminated FM severity (AUC = 0.62 to 0.66; P ≤ 0.05). The 30-s chair stand test showed the highest ability to discriminate FM presence and severity (AUC = 0.92, P < 0.001; and AUC = 0.66, P = 0.008, respectively), being the corresponding discriminating cutoffs 9 and 6 repetitions, respectively. Physical fitness in general, and particularly the 30-s chair stand test, is able to discriminate between women with FM from those without FM, as well as between those with moderate FM from their peers with severe FM. © 2011 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Flying High with Spring.

    ERIC Educational Resources Information Center

    Harrington, Carolyn Lang

    2000-01-01

    Presents an art activity for first grade that uses multicolor scratch paper. Explains that students make scratch-drawings of bird nests, then, as a class, discuss types of birds and bird positions (such as sitting or flying), and finally each creates a bird to add to the nest. (CMK)

  14. U-Boats in the Bay of Biscay. An Essay in Operations Analysis

    DTIC Science & Technology

    1990-01-01

    an approach was once seen as the only way to write large com- puter programs from scratch: beginners who mistakenly work from the bottom up generate...178-79 Flowchart . See Models and Analyses Hitler, Adolph (Chancellor), 4, 26, Map 156, 162 "Force multiplier" concept, 118 Hohentwiel aircraft-warning

  15. Expression of Hsp70 reveals significant differences between fin regeneration and inflammation in Paramisgurnus dabryanus.

    PubMed

    Li, Li; Wang, Linlin; He, Jingya; Chang, Zhongjie

    2017-05-01

    Hsp70 is the most strongly induced in response to various cellular stresses and a good candidate for investigating its role in tissue injury. We firstly cloned full-length cDNA of hsp70 from Paramisgurnus dabryanus (PdHsp70) by RACE method (GenBank: KP402408.1). Then regeneration and inflammation of fin were established by amputation and scratch respectively. Quantitative RT-PCR detected the PdHsp70 began to increase rapidly its expression at 1 days post amputation (dpa) and reached the peak at 2 dpa during fin regeneration. Its expression was also up-regulated at 2 days post scratch (dps) of inflammation but still significant weaker in comparison with it in regenerated fin at 2 dpa. Next, immunohistochemistry analysis of PdHsp70 showed that PdHsp70 located mainly in the deeper epidermis of regenerated fin and was stronger than its expression in the scratched inflammatory fin which was involved in whole epidermal. SDS-PAGE and Western blotting confirmed that the PdHsp70 protein expressed efficiently in Escherichia coli BL21. These findings have implied that PdHsp70 are implicated in different regulation of regeneration and inflammation in response to injury stimulation. During the regeneration, it is involved in the formation of wound epidermis by mediating cellular protection whereas it can modulate inflammatory by activating the innate immune response. Copyright © 2017. Published by Elsevier Ltd.

  16. Spike threshold dynamics in spinal motoneurons during scratching and swimming.

    PubMed

    Grigonis, Ramunas; Alaburda, Aidas

    2017-09-01

    Action potential threshold can vary depending on firing history and synaptic inputs. We used an ex vivo carapace-spinal cord preparation from adult turtles to study spike threshold dynamics in motoneurons during two distinct types of functional motor behaviour - fictive scratching and fictive swimming. The threshold potential depolarizes by about 10 mV within each burst of spikes generated during scratch and swim network activity and recovers between bursts to a slightly depolarized level. Slow synaptic integration resulting in a wave of membrane potential depolarization is the factor influencing the threshold potential within firing bursts during motor behaviours. Depolarization of the threshold potential decreases the excitability of motoneurons and may provide a mechanism for stabilization of the response of a motoneuron to intense synaptic inputs to maintain the motor commands within an optimal range for muscle activation. During functional spinal neural network activity motoneurons receive intense synaptic input, and this could modulate the threshold for action potential generation, providing the ability to dynamically adjust the excitability and recruitment order for functional needs. In the present study we investigated the dynamics of action potential threshold during motor network activity. Intracellular recordings from spinal motoneurons in an ex vivo carapace-spinal cord preparation from adult turtles were performed during two distinct types of motor behaviour - fictive scratching and fictive swimming. We found that the threshold of the first spike in episodes of scratching and swimming was the lowest. The threshold potential depolarizes by about 10 mV within each burst of spikes generated during scratch and swim network activity and recovers between bursts to a slightly depolarized level. Depolarization of the threshold potential results in decreased excitability of motoneurons. Synaptic inputs do not modulate the threshold of the first action potential during episodes of scratching or of swimming. There is no correlation between changes in spike threshold and interspike intervals within bursts. Slow synaptic integration that results in a wave of membrane potential depolarization rather than fast synaptic events preceding each spike is the factor influencing the threshold potential within firing bursts during motor behaviours. © 2017 The Authors. The Journal of Physiology © 2017 The Physiological Society.

  17. Differences in Functional Fitness Among Older Adults With and Without Risk of Falling.

    PubMed

    Zhao, Yanan; Chung, Pak-Kwong

    2016-03-01

    This study aimed to identify the differences in functional fitness between older adults who were at risk of falling and those who were not. A total of 104 older adults aged 65-74 years were recruited from a local community senior center. They were independent older adults without a history of falls in the preceding 12 months. Falling risk status was assessed using the Fall Risk Test. Five dimensions of functional fitness with seven testing parameters (i.e., 30-second chair stand test, 30-second arm curl test, 2-minute step test, chair sit and reach test, back scratch test, 8-foot up and go test, and body mass index) were evaluated by the Senior Fitness Test. Only 78 participants completed all the tests, of which 48 participants were identified with risk of falling, and 30 participants were free from risk of falling. Results from multivariate analysis of variance found significant differences on the combined outcome variables, especially in the 8-foot up and go test, 2-minute step test, and 30-second arm curl test. Results from discriminant analysis found a significant discriminant function among all the seven testing parameters, where the 8-foot up and go test, and the 2-minute step test contributed most. Older adults who are at the early stage of risk of falling tend to have lower functional fitness capacities, especially in agility and dynamic balance, aerobic endurance as well as in a combined relationship among all the testing parameters. Copyright © 2016. Published by Elsevier B.V.

  18. Enhanced non-peptidergic intraepidermal fiber density and an expanded subset of chloroquine-responsive trigeminal neurons in a mouse model of dry skin itch

    PubMed Central

    Valtcheva, Manouela V.; Samineni, Vijay K.; Golden, Judith P.; Gereau, Robert W.; Davidson, Steve

    2015-01-01

    Chronic pruritic conditions are often associated with dry skin and loss of epidermal barrier integrity. In this study, repeated application of acetone and ether, followed by water (AEW) to the cheek skin of mice produced persistent scratching behavior with no increase in pain-related forelimb wiping, indicating the generation of itch without pain. Cheek skin immunohistochemistry showed a 64.5% increase in total epidermal innervation in AEW-treated mice compared to water-treated controls. This increase was independent of scratching, because mice prevented from scratching by Elizabethan collars showed similar hyperinnervation. To determine the effects of dry skin treatment on specific subsets of peripheral fibers, we examined Ret-positive, CGRP-positive, and GFRα3-positive intraepidermal fiber density. AEW treatment increased Ret-positive fibers, but not CGRP-positive or GFRα3-positive fibers, suggesting that a specific subset of non-peptidergic fibers could contribute to dry skin itch. To test whether trigeminal ganglion neurons innervating the cheek exhibited altered excitability after AEW treatment, primary cultures of retrogradely labeled neurons were examined using whole-cell patch clamp electrophysiology. AEW treatment produced no differences in measures of excitability compared to water-treated controls. In contrast, a significantly higher proportion of trigeminal ganglion neurons were responsive to the non-histaminergic pruritogen chloroquine after AEW treatment. We conclude that non-peptidergic, Ret-positive fibers and chloroquine-sensitive neurons may contribute to dry skin pruritus. PMID:25640289

  19. BioBlend: automating pipeline analyses within Galaxy and CloudMan.

    PubMed

    Sloggett, Clare; Goonasekera, Nuwan; Afgan, Enis

    2013-07-01

    We present BioBlend, a unified API in a high-level language (python) that wraps the functionality of Galaxy and CloudMan APIs. BioBlend makes it easy for bioinformaticians to automate end-to-end large data analysis, from scratch, in a way that is highly accessible to collaborators, by allowing them to both provide the required infrastructure and automate complex analyses over large datasets within the familiar Galaxy environment. http://bioblend.readthedocs.org/. Automated installation of BioBlend is available via PyPI (e.g. pip install bioblend). Alternatively, the source code is available from the GitHub repository (https://github.com/afgane/bioblend) under the MIT open source license. The library has been tested and is working on Linux, Macintosh and Windows-based systems.

  20. Design and fabrication of prototype system for early warning of impending bearing failure

    NASA Technical Reports Server (NTRS)

    Broderick, J. J.; Burchill, R. F.; Clark, H. L.

    1972-01-01

    Ball bearing performance tests run on several identical ball bearings under a variety of load, speed, temperature, and lubrication conditions are reported. Bearing temperature, torque, vibration, noise, strain, cage speed, etc., were monitored to establish those measurements most suitable as indicators of ball bearing health. Tape records were made under steady-state conditions of a variety of speeds and loads. Sample sections were selected for narrowband spectral analysis with a real time analyzer. An artificial flow was created across the inner race surface of one bearing using an acid etch technique to produce the scratch. Tape records obtained before and after established a characteristic frequency response that identifies the presence of the flow. The signals found most useful as indicators of performance degradation were ultrasonic outputs.

  1. An evaluation of the effectiveness of S-5 scratch courses.

    DOT National Transportation Integrated Search

    1976-01-01

    A study was made of the practice of "scratching" the surface course of several new construction projects in Virginia. It was found that sections with the surface course placed in one lift produced a road roughness value of about 3 in./mile higher tha...

  2. Characterization of Intercalated Graphite Fibers for Microelectromechanical Systems (MEMS) Applications

    DTIC Science & Technology

    2007-03-01

    electric charge to drive movement, eg. a micromirror . These two actuator types have different characteristics and apply dif- ferent forces. The thermal...actuators include micromirrors , comb drives, cantilevers and scratch drives. A scratch drive actuator uses an applied square wave voltage to operate, as

  3. Formative Evaluation Information from Scripts, Scratch Tracks, and Rough Cuts: A Comparison.

    ERIC Educational Resources Information Center

    Burton, John K.; Aversa, Frances M.

    1979-01-01

    To assess how early in the development of content materials for a televised course learner review should occur, data were gathered from adult students who reviewed either the script, scratch track audiotape, or rough cut videotape for a course on Japan. (Author/JEG)

  4. Experimentally validated 3D MD model for AFM-based tip-based nanomanufacturing

    NASA Astrophysics Data System (ADS)

    Promyoo, Rapeepan

    In order to control AFM-based TBN to produce precise nano-geometry efficiently, there is a need to conduct a more focused study of the effects of different parameters, such as feed, speed, and depth of cut on the process performance and outcome. This is achieved by experimentally validating a MD simulation model of nanomachining, and using it to conduct parametric studies to guide AFM-based TBN. A 3D MD model with a larger domain size was developed and used to gain a unique insight into the nanoindentation and nanoscratching processes such as the effect of tip speed (e.g. effect of tip speed on indentation force above 10 nm of indentation depth). The model also supported a more comprehensive parametric study (than other published work) in terms of number of parameters and ranges of values investigated, as well as a more cost effective design of experiments. The model was also used to predict material properties at the nanoscale (e.g. hardness of gold predicted within 6% error). On the other hand, a comprehensive experimental parametric study was conducted to produce a database that is used to select proper machining conditions for guiding the fabrication of nanochannels (e.g. scratch rate = 0.996 Hz, trigger threshold = 1 V, for achieving a nanochannel depth = 50 nm for the case of gold device). Similar trends for the variation of indentation force with depth of cut, pattern of the material pile-up around the indentation mark or scratched groove were found. The parametric studies conducted using both MD model simulations and AFM experiments showed the following: Normal forces for both nanoindentation and nanoscratching increase as the depth of cut increases. The indentation depth increases with tip speed, but the depth of scratch decrease with increasing tip speed. The width and depth of scratched groove also depend on the scratch angle. The recommended scratch angle is at 90°. The surface roughness increases with step over, especially when the step over is larger than the tip radius. The depth of cut also increases as the step over decreases. Additional study is conducted using the MD model to understand the effect of crystal structure and defects in material when subjected to a stress. Several types of defects, including vacancies and Shockley partial dislocation loops, can be observed during the MD simulation for the case of gold, copper and aluminum. Finally, AFM-based TBN is used with photolithography to fabricate a nano-fluidic device for medical application. In fact, the photolithography process is used to create microchannels on top of a silicon wafer, and AFM-based TBN is applied to fabricate nanochannels between the microchannels that connect to the reservoirs. Fluid flow test was conducted on the devices to ensure that the nanochannel was open and the bonding sealed.

  5. The Neuropeptide Y system regulates both mechanical and histaminergic itch.

    PubMed

    Gao, Tianle; Ma, Haisha; Xu, Bo; Bergman, Jessica; Larhammar, Dan; Lagerström, Malin Charlotta

    2018-05-24

    Itch is a somatosensory modality that serves to alert the organism to harmful elements removable by scratching, such as parasites and chemical irritants. Recently, ablation or silencing of neuropeptide Y (NPY)-expressing spinal interneurons was reported to selectively enhance mechanical itch whereas chemical itch was unaffected. We have examined the effect of activating the NPY/Y 1 receptor system on scratch behavior in mouse. We found that intrathecal administration of the Y 1 agonist [Leu 31 ,Pro 34 ]-NPY (LP-NPY) attenuated itch behavior induced by application of 0.07 g von Frey filament in the nape of the neck, compared to saline treatment, indicating that activation of the spinal NPY/Y 1 system dampens mechanical itch. However, intrathecal administration of LP-NPY also attenuated chemically induced scratching provoked by intradermal application of histamine or the mast cell degranulator 48/80 (histaminergic itch), and the latter effect could be reversed by administration of the Y 1 antagonist BIBO3304. Intrathecal application of the native non-selective agonist NPY also attenuated histamine or 48/80-induced scratching. Our analyses emphasize the importance of including additional quantitative parameters to characterize the full spectrum of itch behavior and show that the NPY/Y 1 system dampens both mechanically and chemically induced scratching and hence is shared by the two sub-modalities of itch. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  6. Rabies-related knowledge and practices among persons at risk of bat exposures in Thailand.

    PubMed

    Robertson, Kis; Lumlertdacha, Boonlert; Franka, Richard; Petersen, Brett; Bhengsri, Saithip; Henchaichon, Sununta; Peruski, Leonard F; Baggett, Henry C; Maloney, Susan A; Rupprecht, Charles E

    2011-06-01

    Rabies is a fatal encephalitis caused by lyssaviruses. Evidence of lyssavirus circulation has recently emerged in Southeast Asian bats. A cross-sectional study was conducted in Thailand to assess rabies-related knowledge and practices among persons regularly exposed to bats and bat habitats. The objectives were to identify deficiencies in rabies awareness, describe the occurrence of bat exposures, and explore factors associated with transdermal bat exposures. A survey was administered to a convenience sample of adult guano miners, bat hunters, game wardens, and residents/personnel at Buddhist temples where mass bat roosting occurs. The questionnaire elicited information on demographics, experience with bat exposures, and rabies knowledge. Participants were also asked to describe actions they would take in response to a bat bite as well as actions for a bite from a potentially rabid animal. Bivariate analysis was used to compare responses between groups and multivariable logistic regression was used to explore factors independently associated with being bitten or scratched by a bat. Of 106 people interviewed, 11 (10%) identified bats as a potential source of rabies. A history of a bat bite or scratch was reported by 29 (27%), and 38 (36%) stated either that they would do nothing or that they did not know what they would do in response to a bat bite. Guano miners were less likely than other groups to indicate animal bites as a mechanism of rabies transmission (68% vs. 90%, p=0.03) and were less likely to say they would respond appropriately to a bat bite or scratch (61% vs. 27%, p=0.003). Guano mining, bat hunting, and being in a bat cave or roost area more than 5 times a year were associated with history of a bat bite or scratch. These findings indicate the need for educational outreach to raise awareness of bat rabies, promote exposure prevention, and ensure appropriate health-seeking behaviors for bat-inflicted wounds, particularly among at-risk groups in Thailand.

  7. Afferent control of central pattern generators: experimental analysis of locomotion in the decerebrate cat.

    PubMed

    Baev, K V; Esipenko, V B; Shimansky YuP

    1991-01-01

    Changes in the motor activity of the spinal locomotor generator evoked by tonic and phasic peripheral afferent signals during fictitious locomotion of both slow and fast rhythms were analysed in the cat. The tonic afferent inflow was conditioned by the position of the hindlimb. The phasic afferent signals were imitated by electrical stimulation of hindlimb nerves. The correlation between the kinematics of hindlimb locomotor movement and sensory inflow was investigated during actual locomotion. Reliable correlations between motor activity parameters during fictitious locomotion were revealed in cases of both slow and fast "locomotor" rhythms. The main difference between these cases was that correlations "duration-intensity" were positive in the first and negative in the second case. The functional role of "locomotor" pattern dependence on tonic sensory inflow consisted of providing stability for planting the hindlimb on the ground. For any investigated afferent input the phase moments in the "locomotor" cycle were found, in which an afferent signal caused no rearrangement in locomotor generator activity. These moments corresponded to the transitions between "flexion" and "extension" phases and to the bursts of integral afferent activity observed during real locomotion. The data obtained are compared with the results previously described for the scratching generator. The character of changes in "locomotor" activity in response to tonic and phasic sensory signals was similar to that of such changes in "scratching" rhythm in the case of fast "locomotion". Intensification of the "flexion" phase caused by phasic high-intensity stimulation of cutaneous afferents during low "locomotor" rhythm was changed to inhibition (such as observed during "scratching") when this rhythm was fast. It is concluded that the main regularities of peripheral afferent control for both the locomotor and scratching generators are the same. Moreover, these central pattern generators are just working regimes of a general spinal motor optimal control system containing the intrinsic model of limb movement dynamics. The consequences of this concept and ways of further research are discussed.

  8. Alice, Greenfoot, and Scratch--A Discussion

    ERIC Educational Resources Information Center

    Utting, Ian; Cooper, Stephen; Kolling, Michael; Maloney, John; Resnick, Mitchel

    2010-01-01

    This article distills a discussion about the goals, mechanisms, and effects of three environments which aim to support the acquisition and development of computing concepts (problem solving and programming) in pre-University and non-technical students: Alice, Greenfoot, and Scratch. The conversation started in a special session on the topic at the…

  9. "Scratch"ing below the Surface: Mathematics through an Alternative Digital Lens?

    ERIC Educational Resources Information Center

    Calder, Nigel; Taylor, Merilyn

    2010-01-01

    A key element in the examination of how students process mathematics through digital technologies is considering the ways that digital pedagogical media might influence the learning process. How might students' understanding emerge through engagement in a digital-learning environment? Interactive software that has cross-curricula implications and…

  10. The From Scratch Rhythm Workbook. Revised Edition.

    ERIC Educational Resources Information Center

    Dadson, Philip; McGlashan, Don

    Since its formation in 1974, the renowned performing group, "From Scratch," has developed a distinctive style of music using sophisticated rhythmic language and unique sculptural instruments. The group's experiences have been transformed into the exercises and game forms presented in this workbook. The hands-on workbook uses a body-based…

  11. Synchronization in Scratch: A Case Study with Education Science Students

    ERIC Educational Resources Information Center

    Nikolos, Dimitris; Komis, Vassilis

    2015-01-01

    The Scratch programming language is an introductory programming language for students. It is also a visual concurrent programming language, where multiple threads are executed simultaneously. Synchronization in concurrent languages is a complex task for novices to understand. Our research is focused on strategies and methods applied by novice…

  12. Cat-scratch disease presenting as a solitary splenic abscess in an elderly man.

    PubMed

    Nakamura, Momoko; Kurimoto, Mio; Kato, Takehiro; Kunieda, Takeshige

    2015-03-24

    Patients with cat-scratch disease (CSD), which is caused by Bartonella henselae, typically present with local lymphadenopathy with a brief period of fever and general symptoms. Most cases are self-limiting and usually afflict children and young adults. Although rare, CSD can lead to serious complications, especially in immunocompromised patients. These rare complications often require intensive treatment. We describe the case of a 79-year-old man who presented with general malaise and a high fever. The physical examination findings were unremarkable. Of note, the lymph nodes were not enlarged. An abdominal CT scan with intravenous contrast revealed a solitary splenic abscess and no lymphadenopathy. The initial antibiotic treatment was ineffective and a splenectomy was indicated. A history of contact with cats raised the possibility of CSD, which was confirmed by a positive serology test result for B henselae. Antibiotic treatment with azithromycin successfully treated the splenic abscess and splenectomy was avoided. 2015 BMJ Publishing Group Ltd.

  13. Effects of Voltage on Microstructure and Corrosion Resistance of Micro-arc Oxidation Ceramic Coatings Formed on KBM10 Magnesium Alloy

    NASA Astrophysics Data System (ADS)

    Lu, J. P.; Cao, G. P.; Quan, G. F.; Wang, C.; Zhuang, J. J.; Song, R. G.

    2018-01-01

    Micro-arc oxidation (MAO) coatings on KBM10 magnesium alloy were prepared in an electrolyte system with sodium silicate, potassium hydroxide, sodium tungstate, and citric acid. The effects of voltage on the microstructure and corrosion resistance of MAO coatings were studied using stereoscopic microscopy, scanning electron microscopy, x-ray diffraction, scratch tests, potentiodynamic polarization, and electrochemical impedance spectroscopy. The results showed that the roughness of the MAO coatings, diameter, and number of pores increase with the increase in voltage. The coating formed at the voltage of 350 V exhibited the best adhesive strength when evaluated by the automatic scratch tester. The coatings were mainly composed of MgO, MgWO4, and Mg2SiO4, and the content of Mg2SiO4 increased with the increase in voltage. The corrosion resistance of MAO coatings could be improved by changing the applied voltage, and the best corrosion resistance of MAO coating was observed at the voltage of 350 V.

  14. Low-Temperature Self-Healing of a Microcapsule-Type Protective Coating.

    PubMed

    Kim, Dong-Min; Cho, Yu-Jin; Choi, Ju-Young; Kim, Beom-Jun; Jin, Seung-Won; Chung, Chan-Moon

    2017-09-14

    Low-temperature self-healing capabilities are essential for self-healing materials exposed to cold environments. Although low-temperature self-healing concepts have been proposed, there has been no report of a microcapsule-type low-temperature self-healing system wherein the healing ability was demonstrated at low temperature. In this work, low-temperature self-healing of a microcapsule-type protective coating was demonstrated. This system employed silanol-terminated polydimethylsiloxane (STP) as a healing agent and dibutyltin dilaurate (DD) as a catalyst. STP underwent a condensation reaction at -20 °C in the presence of DD to give a viscoelastic product. The reaction behavior of STP and the viscoelasticity of the reaction product were investigated. STP and DD were separately microencapsulated by in situ polymerization and interfacial polymerization methods, respectively. The STP- and DD-loaded microcapsules were mixed into a commercial enamel paint, and the resulting formulation was applied to glass slides, steel panels, and mortars to prepare self-healing coatings. When the self-healing coatings were damaged at a low temperature (-20 °C), STP and DD were released from broken microcapsules and filled the damaged area. This process was effectively visualized using a fluorescent dye. The self-healing coatings were scratched and subjected to corrosion tests, electrochemical tests, and saline solution permeability tests. The temperature of the self-healing coatings was maintained at -20 °C before and after scratching and during the tests. We successfully demonstrated that the STP/DD-based coating system has good low-temperature self-healing capability.

  15. Review of fatigue and fracture research at NASA Langley Research Center

    NASA Technical Reports Server (NTRS)

    Everett, Richard A., Jr.

    1988-01-01

    Most dynamic components in helicopters are designed with a safe-life constant-amplitude testing approach that has not changed in many years. In contrast, the fatigue methodology in other industries has advanced significantly in the last two decades. Recent research at the NASA Langley Research Center and the U.S. Army Aerostructures Directorate at Langley are reviewed relative to fatigue and fracture design methodology for metallic components. Most of the Langley research was directed towards the damage tolerance design approach, but some work was done that is applicable to the safe-life approach. In the areas of testing, damage tolerance concepts are concentrating on the small-crack effect in crack growth and measurement of crack opening stresses. Tests were conducted to determine the effects of a machining scratch on the fatigue life of a high strength steel. In the area of analysis, work was concentrated on developing a crack closure model that will predict fatigue life under spectrum loading for several different metal alloys including a high strength steel that is often used in the dynamic components of helicopters. Work is also continuing in developing a three-dimensional, finite-element stress analysis for cracked and uncracked isotropic and anisotropic structures. A numerical technique for solving simultaneous equations called the multigrid method is being pursued to enhance the solution schemes in both the finite-element analysis and the boundary element analysis. Finally, a fracture mechanics project involving an elastic-plastic finite element analysis of J-resistance curve is also being pursued.

  16. Effect of different methods of preliminary surface treatment and magnetron sputtering on the adhesion of Si coatings

    NASA Astrophysics Data System (ADS)

    Borisov, D. P.; Slabodchikov, V. A.; Kuznetsov, V. M.

    2017-05-01

    The paper presents research results on the adhesion of Si coatings deposited by magnetron sputtering on NiTi substrates after preliminary surface treatment (cleaning and activation) with low-energy ion beams and gas discharge plasma. The adhesion properties of the coatings obtained by two methods are analyzed and compared using data of scratch and spherical abrasion tests.

  17. Aminosilane multilayer formed on a single-crystalline diamond surface with controlled nanoscopic hardness and bioactivity by a wet process.

    PubMed

    Amemiya, Yosuke; Hatakeyama, Akiko; Shimamoto, Nobuo

    2009-01-06

    Diamond could be an excellent support for nanodevices utilizing biomolecules if it is covered with a polymer layer immobilizing a variety of biomolecules. We report a wet method to form a 3-aminopropyltriethoxysilane (APTES) multilayer with a controlled hardness, roughness, and capacity for immobilizing protein. The method is feasible in typical biochemical laboratories where biomolecules are prepared. Atomic force microscopy (AFM) revealed that the surface geometries and nanoscopic hardness of the multilayers on an oxygen-terminated single-crystalline diamond surface depended on the dielectric constant of the solvent; the smaller the constant, the harder the layer. The hard multilayers had holes and APTES aggregates on the surfaces, while less hard ones had homogeneous surfaces with rare holes and little aggregates. The secondary deposition of APTES in a solvent with a large dielectric constant on a hard multilayer removed the holes, and further treatment of the multilayer in acidic ethanol solution diminished the aggregates. Such a surface can immobilize streptavidin with enough specificity against nonspecific adsorption using a combination of polyethylene glycol reagents. The results of a scratching test and nanoindentation test with AFM provided consistent results, suggesting some universality of the scratching test independent of the tip structure of the cantilever. The mechanism of formation of multilayers on the diamond surface and their binding to it is discussed.

  18. How to Study a Tone Language, with Exemplification from Oku (Grassfields Bantu, Cameroon)

    ERIC Educational Resources Information Center

    Hyman, Larry M.

    2014-01-01

    In response to requests I have often got as to how one approaches a tone language, I present a personal view of the three stages involved, starting from scratch and arriving at an analysis: Stage I: Determining the tonal contrasts and their approximate phonetic allotones. Stage II: Discovering any tonal alternations ("morphotonemics").…

  19. LAN Configuration and Analysis: Projects for the Data Communications and Networking Course

    ERIC Educational Resources Information Center

    Chen, Fang; Brabston, Mary

    2011-01-01

    We implemented two local area network (LAN) projects in our introductory data communications and networking course. The first project required students to develop a LAN from scratch for a small imaginary organization. The second project required student groups to analyze a LAN for a real world small organization. By allowing students to apply what…

  20. Nanoscale patterning of Si surface using SPM scratching

    NASA Astrophysics Data System (ADS)

    Ogino, T.; Nishimura, S.; Shirakashi, J.

    2008-03-01

    Nanolithography of Si surface using scanning probe microscopy (SPM) scratching with a diamond-coated tip was systematically investigated at a low force regime below 9 μN. The groove patterns with controlled width and depth could be achieved by adjusting the applied force, scan direction and the number of scan cycles. There was no effect of scan speed on the groove size. The minimum groove width of 10 nm was obtained on Si surfaces. Furthermore, more complex nanostructures such as line and space patterns of 30 nm pith and dot arrays of 2.6×1010 cm-2 density were realized. SPM scratching with a diamond-coated tip allows nanoscale patterning of Si surfaces to be performed simply.

  1. Testing the interspecific body size principle in ungulates: the smaller they come, the harder they groom.

    PubMed

    Mooring; Benjamin; Harte; Herzog

    2000-07-01

    Tick removal grooming may be centrally regulated by an internal timing mechanism operating to remove ticks before they attach and engorge (programmed grooming model) and/or evoked by cutaneous stimulation from tick bites (stimulus-driven model). The programmed grooming model predicts that organismic and environmental factors that impact the cost-benefit ratio of grooming (e.g. body size and habitat) will influence the rate of tick removal grooming. The body size principle predicts that smaller-sized animals, because of their greater surface-to-mass ratio, should engage in more frequent tick removal grooming than larger-bodied animals in order to compensate for higher costs of tick infestation. The body size principle may be tested intraspecifically between young and adult animals, or interspecifically among species of contrasting body sizes. To rigorously test the interspecific body size prediction, we observed the programmed grooming (oral and scratch grooming) of 25 species (or subspecies) of bovids at a tick-free zoological park in which stimulus-driven grooming was ruled out. Multiple correlation analysis revealed highly significant negative correlations between species-typical mass and mean species grooming rates when habitat was controlled for in the model. Species-typical habitat type (classified along a gradient from most open to most closed) was positively correlated with mean oral grooming rate, indicating that species tended to groom at a higher rate in woodland and forest habitats (where typical tick density would be high) compared with more open environments. Species mass accounted for up to two-thirds of the variation in grooming rate across species, whereas habitat accounted for ca. 20% of variation in oral grooming. Similar results were obtained when the analysis was expanded to include 36 species/subspecies of six different families. The body size principle can therefore account for a large proportion of species-typical differences in programmed grooming rate among ungulates. However, to understand the tick defence adaptations of very large mammals that rarely or never engage in oral or scratch grooming (e.g. elephants, giraffes, rhinoceros), alternative tick defence strategies must be considered, such as thick skin, wallowing, rubbing and tolerance of oxpeckers and other tick-eating birds. Copyright 2000 The Association for the Study of Animal Behaviour.

  2. Starting from Scratch: A New Federal and State Partnership in Higher Education

    ERIC Educational Resources Information Center

    McCarthy, Mary Alice; Fishman, Rachel; Palmer, Iris; Laitinen, Amy; Dancy, Kim; Burd, Stephen; Carey, Kevin; Ekowo, Manuela; Barrett, Ben; Holt, Alexander

    2016-01-01

    Imagine students attending colleges and universities around the country having their financial needs met without the use of federal loans, Pell Grants, and higher education tax credits. In "Starting from Scratch: A New Federal and State Partnership in Higher Education," New America's Higher Education Policy Program shares its vision for…

  3. Improving response rate and quality of survey data with a scratch lottery ticket incentive

    PubMed Central

    2012-01-01

    Background The quality of data collected in survey research is usually indicated by the response rate; the representativeness of the sample, and; the rate of completed questions (item-response). In attempting to improve a generally declining response rate in surveys considerable efforts are being made through follow-up mailings and various types of incentives. This study examines effects of including a scratch lottery ticket in the invitation letter to a survey. Method Questionnaires concerning oral health were mailed to a random sample of 2,400 adults. A systematically selected half of the sample (1,200 adults) received a questionnaire including a scratch lottery ticket. One reminder without the incentive was sent. Results The incentive increased the response rate and improved representativeness by reaching more respondents with lower education. Furthermore, it reduced item nonresponse. The initial incentive had no effect on the propensity to respond after the reminder. Conclusion When attempting to improve survey data, three issues become important: response rate, representativeness, and item-response. This study shows that including a scratch lottery ticket in the invitation letter performs well on all the three. PMID:22515335

  4. Optical fringe-reflection deflectometry with sparse representation

    NASA Astrophysics Data System (ADS)

    Xiao, Yong-Liang; Li, Sikun; Zhang, Qican; Zhong, Jianxin; Su, Xianyu; You, Zhisheng

    2018-05-01

    Optical fringe-reflection deflectometry is a surprisingly attractive scratch detection technique for specular surfaces owing to its unparalleled local sensibility. Full-field surface topography is obtained from a measured normal field using gradient integration. However, there may not be an ideal measured gradient field for deflectometry reconstruction in practice. Both the non-integrability condition and various kinds of image noise distributions, which are present in the indirect measured gradient field, may lead to ambiguity about the scratches on specular surfaces. In order to reduce misjudgment of scratches, sparse representation is introduced into the Southwell curl equation for deflectometry. The curl can be represented as a linear combination of the given redundant dictionary for curl and the sparsest solution for gradient refinement. The non-integrability condition and noise permutation can be overcome with sparse representation for gradient refinement. Numerical simulations demonstrate that the accuracy rate of judgment of scratches can be enhanced with sparse representation compared to the standard least-squares integration. Preliminary experiments are performed with the application of practical measured deflectometric data to verify the validity of the algorithm.

  5. A Large-Sample Test of a Semi-Automated Clavicle Search Engine to Assist Skeletal Identification by Radiograph Comparison.

    PubMed

    D'Alonzo, Susan S; Guyomarc'h, Pierre; Byrd, John E; Stephan, Carl N

    2017-01-01

    In 2014, a morphometric capability to search chest radiograph databases by quantified clavicle shape was published to assist skeletal identification. Here, we extend the validation tests conducted by increasing the search universe 18-fold, from 409 to 7361 individuals to determine whether there is any associated decrease in performance under these more challenging circumstances. The number of trials and analysts were also increased, respectively, from 17 to 30 skeletons, and two to four examiners. Elliptical Fourier analysis was conducted on clavicles from each skeleton by each analyst (shadowgrams trimmed from scratch in every instance) and compared to the search universe. Correctly matching individuals were found in shortlists of 10% of the sample 70% of the time. This rate is similar to, although slightly lower than, rates previously found for much smaller samples (80%). Accuracy and reliability are thereby maintained, even when the comparison system is challenged by much larger search universes. © 2016 American Academy of Forensic Sciences.

  6. Parameterized examination in econometrics

    NASA Astrophysics Data System (ADS)

    Malinova, Anna; Kyurkchiev, Vesselin; Spasov, Georgi

    2018-01-01

    The paper presents a parameterization of basic types of exam questions in Econometrics. This algorithm is used to automate and facilitate the process of examination, assessment and self-preparation of a large number of students. The proposed parameterization of testing questions reduces the time required to author tests and course assignments. It enables tutors to generate a large number of different but equivalent dynamic questions (with dynamic answers) on a certain topic, which are automatically assessed. The presented methods are implemented in DisPeL (Distributed Platform for e-Learning) and provide questions in the areas of filtering and smoothing of time-series data, forecasting, building and analysis of single-equation econometric models. Questions also cover elasticity, average and marginal characteristics, product and cost functions, measurement of monopoly power, supply, demand and equilibrium price, consumer and product surplus, etc. Several approaches are used to enable the required numerical computations in DisPeL - integration of third-party mathematical libraries, developing our own procedures from scratch, and wrapping our legacy math codes in order to modernize and reuse them.

  7. Validity of the International Fitness Scale "IFIS" in older adults.

    PubMed

    Merellano-Navarro, Eugenio; Collado-Mateo, Daniel; García-Rubio, Javier; Gusi, Narcís; Olivares, Pedro R

    2017-09-01

    To validate the "International Fitness Scale" (IFIS) in older adults. Firstly, cognitive interviews were performed to ensure that the questionnaire was comprehensive for older Chilean adults. After that, a transversal study of 401 institutionalized and non-institutionalized older adults from Maule region in Chile was conducted. A battery of validated fitness tests for this population was used in order to compare the responses obtained in the IFIS with the objectively measured fitness performance (back scratch, chair sit-and-reach, handgrip, 30-s chair stand, timed up-and-go and 6-min walking). Indicated that IFIS presented a high compliance in the comprehension of the items which defined it, and it was able of categorizing older adults according to their measured physical fitness levels. The analysis of covariance ANCOVA adjusted by sex and age showed a concordance between IFIS and the score in physical fitness tests. Based on the results of this study, IFIS questionnaire is a good alternative to assess physical fitness in older adults. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Effects of Hull Scratching, Soaking, and Boiling on Antinutrients in Japanese Red Sword Bean (Canavalia gladiata).

    PubMed

    Une, Satsuki; Nonaka, Koji; Akiyama, Junich

    2016-10-01

    The effects of hull processing, soaking, and boiling on the content or activity of antinutrients in the red sword bean (RSB; Canavalia gladiata) were investigated. RSB seeds were compared with kidney bean (KB; Phaseolus vulgaris) seeds that are starch based and often used as processed products in Japan. RSB seeds had higher weight, thicker hull, and higher protein content, but lower moisture content compared with KB seeds. Because of the strong and thick hull, the relative water absorption of untreated RSB seeds was very low after soaking. Seeds were soaked after dehulling, scratching, and roasting. The results showed that hull scratching was the optimal method for increasing water absorption during soaking compared with dehulling and roasting. After soaking, the water used for soaking was discarded, since it had a high content of polyphenols and bitter taste, and RSB seeds were boiled in fresh water for 20, 40, and 60 min. The results showed that polyphenol and tannin contents, antioxidant activity, and hemagglutinating activity, as well as maltase, sucrase, and trypsin inhibitor activities in scratched RSB seeds decreased significantly after boiling compared with those in raw seeds, whereas amylase inhibitor activity showed no significant change. Overall, it was concluded that the combination of hull scratching, soaking, and boiling in fresh water can reduce thermal-stable or sensitive antinutrients in RSB and thus, significantly improve its nutritional value. © 2016 Institute of Food Technologists®.

  9. Engineered Defects for Investigation of Laser-Induced Damage of Fused Silica at 355nm

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

    Hamza, A V; Siekhaus, W J; Rubenchik, A M

    2001-12-18

    Embedded gold and mechanical deformation in silica were used to investigate initiation of laser-induced damage at 3.55-nm (7.6 ns). The nanoparticle-covered surfaces were coated with between 0 and 500 nm of SiO{sub 2} by e-beam deposition. The threshold for observable damage and initiation site morphology for these ''engineered'' surfaces was determined. The gold nanoparticle coated surfaces with 500nm SiO{sub 2} coating exhibited pinpoint damage threshold of <0.7 J/cm{sup 2} determined by light scattering and Nomarski microscopy. The gold nanoparticle coated surfaces with the 100nm SiO{sub 2} coatings exhibited what nominally appeared to be film exfoliation damage threshold of 19 J/cm{supmore » 2} via light scattering and Nomarski microscopy. With atomic force microscopy pinholes could be detected at fluences greater than 7 J/cm{sup 2} and blisters at fluences greater than 3 J/cm{sup 2} on the 100 nm-coated surfaces. A series of mechanical indents and scratches were made in the fused silica substrates using a nano-indentor. Plastic deformation without cracking led to damage thresholds of -25 J/cm{sup 2}, whereas indents and scratches with cracking led to damage thresholds of only {approx}5 J/cm{sup 2}. Particularly illuminating was the deterministic damage of scratches at the deepest end of the scratch, as if the scratch acted as a waveguide.« less

  10. Endometrial injury to overcome recurrent embryo implantation failure: a systematic review and meta-analysis.

    PubMed

    Potdar, Neelam; Gelbaya, Tarek; Nardo, Luciano G

    2012-12-01

    Mechanical endometrial injury (biopsy/scratch or hysteroscopy) in the cycle preceding ovarian stimulation for IVF has been proposed to improve implantation in women with unexplained recurrent implantation failure (RIF). This is a systematic review and meta-analysis of studies comparing the efficacy of endometrial injury versus no intervention in women with RIF undergoing IVF. All controlled studies of endometrial biopsy/scratch or hysteroscopy performed in the cycle preceding ovarian stimulation were included and the primary outcome measure was clinical pregnancy rate. Pooling of seven controlled studies (four randomized and three non-randomized), with 2062 participants, showed that local endometrial injury induced in the cycle preceding ovarian stimulation is 70% more likely to result in a clinical pregnancy as opposed to no intervention. There was no statistically significant heterogeneity in the methods used, clinical pregnancy rates being twice as high with biopsy/scratch (RR 2.32, 95% CI 1.72-3.13) as opposed to hysteroscopy (RR 1.51, 95% CI 1.30-1.75). The evidence is strongly in favour of inducing local endometrial injury in the preceding cycle of ovarian stimulation to improve pregnancy outcomes in women with unexplained RIF. However, large randomized studies are required before iatrogenic induction of local endometrial injury can be warranted in routine clinical practice. Some women undergoing IVF treatment fail to conceive despite several attempts with good-quality embryos and no identifiable reason. We call this 'recurrent implantation failure' (RIF) where the embryo fails to embed or implant within the lining of the womb. Studies have shown that inducing injury to the lining of the womb in the cycle before starting ovarian stimulation for IVF can help improve the chances of achieving pregnancy. Injury can be induced by either scratching the lining of the womb using a biopsy tube or by telescopic investigation of the womb using a camera. We performed a collective review of the available good-quality studies that used the above two methods in the cycle prior to starting ovarian stimulation for IVF. We pooled results from seven studies, which included 2062 women with RIF and assessed the difference in clinical pregnancy rates for those undergoing injury to the womb lining compared with no injury prior to IVF. The results suggest that inducing injury is 70% more likely to result in a clinical pregnancy as opposed to no treatment. Furthermore, scratching of the lining was 2-times more likely to result in a clinical pregnancy compared with telescopic evaluation of the lining of the womb. This study suggests that in women with RIF, inducing local injury to the womb lining in the cycle prior to starting ovarian stimulation for IVF can improve pregnancy outcomes. However, large studies are required before this can be warranted in routine clinical practice. Copyright © 2012 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  11. Discrete and Continuum Approximations for Collective Cell Migration in a Scratch Assay with Cell Size Dynamics.

    PubMed

    Matsiaka, Oleksii M; Penington, Catherine J; Baker, Ruth E; Simpson, Matthew J

    2018-04-01

    Scratch assays are routinely used to study the collective spreading of cell populations. In general, the rate at which a population of cells spreads is driven by the combined effects of cell migration and proliferation. To examine the effects of cell migration separately from the effects of cell proliferation, scratch assays are often performed after treating the cells with a drug that inhibits proliferation. Mitomycin-C is a drug that is commonly used to suppress cell proliferation in this context. However, in addition to suppressing cell proliferation, mitomycin-C also causes cells to change size during the experiment, as each cell in the population approximately doubles in size as a result of treatment. Therefore, to describe a scratch assay that incorporates the effects of cell-to-cell crowding, cell-to-cell adhesion, and dynamic changes in cell size, we present a new stochastic model that incorporates these mechanisms. Our agent-based stochastic model takes the form of a system of Langevin equations that is the system of stochastic differential equations governing the evolution of the population of agents. We incorporate a time-dependent interaction force that is used to mimic the dynamic increase in size of the agents. To provide a mathematical description of the average behaviour of the stochastic model we present continuum limit descriptions using both a standard mean-field approximation and a more sophisticated moment dynamics approximation that accounts for the density of agents and density of pairs of agents in the stochastic model. Comparing the accuracy of the two continuum descriptions for a typical scratch assay geometry shows that the incorporation of agent growth in the system is associated with a decrease in accuracy of the standard mean-field description. In contrast, the moment dynamics description provides a more accurate prediction of the evolution of the scratch assay when the increase in size of individual agents is included in the model.

  12. Real-time scratch assay reveals mechanisms of early calcium signaling in breast cancer cells in response to wounding

    PubMed Central

    Pratt, Stephen J.P.; Hernández-Ochoa, Erick O.; Lee, Rachel M.; Ory, Eleanor C.; Lyons, James S.; Joca, Humberto C.; Johnson, Ashley; Thompson, Keyata; Bailey, Patrick; Lee, Cornell J.; Mathias, Trevor; Vitolo, Michele I.; Trudeau, Matt; Stains, Joseph P.; Ward, Christopher W.; Schneider, Martin F.; Martin, Stuart S.

    2018-01-01

    Aggressive cellular phenotypes such as uncontrolled proliferation and increased migration capacity engender cellular transformation, malignancy and metastasis. While genetic mutations are undisputed drivers of cancer initiation and progression, it is increasingly accepted that external factors are also playing a major role. Two recently studied modulators of breast cancer are changes in the cellular mechanical microenvironment and alterations in calcium homeostasis. While many studies investigate these factors separately in breast cancer cells, very few do so in combination. This current work sets a foundation to explore mechano-calcium relationships driving malignant progression in breast cancer. Utilizing real-time imaging of an in vitro scratch assay, we were able to resolve mechanically-sensitive calcium signaling in human breast cancer cells. We observed rapid initiation of intracellular calcium elevations within seconds in cells at the immediate wound edge, followed by a time-dependent increase in calcium in cells at distances up to 500μm from the scratch wound. Calcium signaling to neighboring cells away from the wound edge returned to baseline within seconds. Calcium elevations at the wound edge however, persisted for up to 50 minutes. Rigorous quantification showed that extracellular calcium was necessary for persistent calcium elevation at the wound edge, but intercellular signal propagation was dependent on internal calcium stores. In addition, intercellular signaling required extracellular ATP and activation of P2Y2 receptors. Through comparison of scratch-induced signaling from multiple cell lines, we report drastic reductions in response from aggressively tumorigenic and metastatic cells. The real-time scratch assay established here provides quantitative data on the molecular mechanisms that support rapid scratch-induced calcium signaling in breast cancer cells. These mechanisms now provide a clear framework for investigating which short-term calcium signals promote long-term changes in cancer cell biology. PMID:29861849

  13. Quantification of polyethylene degradation in mobile bearing knees: a retrieval analysis of the Anterior-Posterior-Glide (APG) and Rotating Platform (RP) Low Contact Stress (LCS) knee.

    PubMed

    Kop, Alan M; Swarts, Eric

    2007-06-01

    Routine qualitative observations of more than 850 polyethylene fixed and mobile bearings at our institution have noted minimal wear of mobile bearings. The APG mobile bearing is the most recent design variant of the LCS knee, allows multi-directional movement at the tibiofemoral articulation, and is posterior cruciate sparing. Even though it is difficult to perform, quantitative wear measurement is important in determining the likely longevity of new arthroplasty devices, and is especially relevant because of increasing numbers of new mobile bearing designs. We analyzed 10 retrieved APG and 7 retrieved RP tibial bearings (De Puy) with a mean implantation period of 33 (9-70) months. We used coordinate-measuring techniques to quantitatively determine linear penetration, and optical and scanning electron microscopy to assess wear mechanisms qualitatively. The mean total volume loss (superior and inferior articulations) of the APG and RP designs was 85 mm((3))/year and 77 mm((3))/year, respectively. Burnishing was the predominant wear mechanism, and to a lesser extent scratching, abrasion and pitting. Multidirectional scratching and abrasion were noted on the APG inserts inferiorly, whereas there was circumferential scratching on the RP inserts. Our short-term results for the APG and RP mobile bearing designs are similar and compare more than favorably with reported values for fixed-bearing designs. However, increased backside wear due to multidirectional movement may predispose the APG design to greater wear in the long term.

  14. Choroidal neovascularisation as an unusual ophthalmic manifestation of cat-scratch disease in an 8-year-old girl.

    PubMed

    Latanza, L; Viscogliosi, F; Solimeo, A; Calabrò, F; De Angelis, V; De Rosa, P

    2015-10-01

    To report the first case of choroidal neovascularisation (CNV) that appeared during the primary Bartonella henselae infection in an 8-year-old girl. An 8-year-old girl was referred to our clinic complaining of a central scotoma in the right eye. Fundus examination revealed a bilateral disc oedema and in the right eye neuroretinitis with macular star and CNV, which was confirmed by fluorescein angiography. The optical coherence tomography revealed the presence of macular serous retinal detachment. Laboratory analysis showed rising IgM and IgG titres for B. henselae. Cat-scratch disease was diagnosed, and an 8-week treatment with azithromycin was initiated. In addition, an intravitreal injection of ranibizumab was performed in the right eye to treat the CNV. A month later, we decided to administer a systemic antibiotic again for an additional 5 months, due to the persistence of papillitis. Cat-scratch disease should be considered among the different causes of inflammatory CNV secondary to infectious uveitis. Our case was the first described in the literature in which a CNV appeared during the primary infection and not as a later complication. The combination of systemic antibiotic treatment with intravitreal anti-VEGF therapy was a successful choice because it allowed us to obtain the complete resolution of neuroretinitis, associated with the scarring of the choroidal neovascular membrane, with a final visual acuity of 20/20 in both eyes.

  15. RAND Workshop on Antiproton Science and Technology, Annotated Executive Summary. (October 6-9, 1987)

    DTIC Science & Technology

    1988-10-01

    parity violation to condensed matter . A number of near-term important applications are possible using the source and portable storage devices...from charge parity violation studies to condensed matter studies. -vi - The CERN/LEAR facility will continue to only scratch the surface of important...technology programs. These technology programs include possible small tools to study extreme states of matter ;, a propulsion test facility for

  16. Structure-Property Relationships in Surface-Modified Ceramics. NATO advanced Science Institutes, Series E: Applied Sciences, Volume 170

    DTIC Science & Technology

    1989-01-01

    channelling and scanning electron microscopy (SEM) of highly oriented pyrolytic graphite ( HOPG ), comparative scratch testing results and some ideas on...electrode graphite , HOPG and carbon fibers also show enhanced wear resistance followoing irradiation (6), the extent of which depends upon the initial...literature dealing with damage effects and physical property changes following neutron irradiation of graphite (single and polycrystalline ) in nuclear

  17. Influence of the interface layer on the adhesion of pulsed laser deposited hydroxyapatite coatings on titanium alloy

    NASA Astrophysics Data System (ADS)

    Fernández-Pradas, J. M.; García-Cuenca, M. V.; Clèries, L.; Sardin, G.; Morenza, J. L.

    2002-07-01

    Hydroxyapatite (HA) coatings were deposited on Ti-6Al-4V substrates by laser ablation with a KrF excimer laser. Depositions were performed at 45 Pa of water vapour and at a substrate temperature of 575 °C. After 7 min of deposition, coatings were left at this temperature for different times before cooling down. The samples morphology and structure were characterised by scanning electron microscopy, X-ray diffractometry and Raman spectroscopy. The mechanical performance of the coatings was evaluated through the scratch-test technique. The coatings do not present important differences between them. However, there is an interface layer between the coating and the substrate that indeed presents an evolution with the heating time. This interface layer is constituted by two different species: titanium oxide and Ti-6Al-4V with oxygen diffused in its lattice. Its thickness increases during the first minutes of heating after deposition. An evolution of the titanium oxide phases with the time of heating has been detected by Raman spectroscopy. The samples fail at lower loads in the scratch-test as longer is the time that they remained at high temperature. The mode of failure of the samples suggests that failure occurs at the interface.

  18. Tribological characterization of TiCN coatings deposited by two crossed laser ablation plasma beams

    NASA Astrophysics Data System (ADS)

    Camps, Enrique; Escobar-Alarcón, L.; Camps, Iván; Muhl, Stephen; Flores, Martín

    2013-03-01

    The simultaneous laser ablation of two targets (graphite and titanium) in an Ar-N2 gas mixture was carried out to deposit thin films of the ternary compound TiCN at room temperature. The base conditions used to produce the TiN without carbon were taken from our previous studies. The experimental conditions for the ablation of the carbon target were varied so that the carbon content in the films could be changed depending on the carbon ion energy. The control of the experimental conditions was carried out using a Langmuir planar probe which permitted the determination of the mean kinetic ion energy. The maximum hardness value of 35 GPa, was obtained with a carbon ion energy of about 250 eV, which corresponds to a film with 5 at% carbon content. In order to perform tribological and scratch tests, two types of substrate were used: nitrided AISI 316 stainless steel and AISI 316 stainless steel previously coated with a thin titanium layer (˜50 nm). Values of the wear rate in the range of 1.39×10-6 to 7.45×10-5 mm3 N-1 m-1, friction coefficient from 0.21 to 0.28 and adhesion from scratch test measurements up to 80 N for final critical load, were obtained.

  19. Streptobacillus moniliformis as the causative agent in spondylodiscitis and psoas abscess after rooster scratches.

    PubMed

    Dubois, Damien; Robin, Frédéric; Bouvier, Damien; Delmas, Julien; Bonnet, Richard; Lesens, Olivier; Hennequin, Claire

    2008-08-01

    We report a case of Streptobacillus moniliformis spondylodiscitis accompanied by a psoas abscess in an 80-year-old man scratched by a rooster. S. moniliformis was identified from abscess fluid by use of 16S rRNA gene sequencing. After 18 weeks of antimicrobial therapy, the clinical condition of the patient improved.

  20. Scratching beyond the Surface of Literacy: Programming for Early Adolescent Gifted Students

    ERIC Educational Resources Information Center

    Hagge, Julia

    2017-01-01

    Digital technology offers new possibilities for children to play, express themselves, learn, and communicate. A recent development in online practice is a shift toward youth engaged in computer programming online communities. Programming is argued to be the new literacy of the millennium. In this article, I examine the use of Scratch, an online…

  1. Comparing among the Experiences of Self-Cutting, Hitting, and Scratching in Chinese Adolescents Attending Secondary Schools: An Interview Study

    ERIC Educational Resources Information Center

    You, Jianing; Ma, Congfen; Lin, Min-Pei; Leung, Freedom

    2015-01-01

    This study examined adolescents' experiences associated with nonsuicidal self-injury (NSSI) and compared among the experiences of self-cutting, hitting, and scratching. Participants included 42 Chinese adolescents attending secondary schools. They had at least three NSSI episodes in the preceding year. Information about their experiences of NSSI…

  2. Improving Reading Comprehension Skills through the SCRATCH Program

    ERIC Educational Resources Information Center

    Papatga, Erdal; Ersoy, Ali

    2016-01-01

    The aim of this study was to reveal how reading comprehension skills of elementary fourth graders who have problems in reading comprehension can be improved by means of the SCRATCH program. The study was designed as a participant action research. It was carried out within a 15- week process at an elementary school with middle socio-economic level…

  3. Scratch as a Computational Modelling Tool for Teaching Physics

    ERIC Educational Resources Information Center

    Lopez, Victor; Hernandez, Maria Isabel

    2015-01-01

    The Scratch online authoring tool, which features a simple programming language that has been adapted to primary and secondary students, is being used more and more in schools as it offers students and teachers the opportunity to use a tool to build scientific models and evaluate their behaviour, just as can be done with computational modelling…

  4. ICT Teachers' Acceptance of "Scratch" as Algorithm Visualization Software

    ERIC Educational Resources Information Center

    Saltan, Fatih; Kara, Mehmet

    2016-01-01

    This study aims to investigate the acceptance of ICT teachers pertaining to the use of Scratch as an Algorithm Visualization (AV) software in terms of perceived ease of use and perceived usefulness. An embedded mixed method research design was used in the study, in which qualitative data were embedded in quantitative ones and used to explain the…

  5. Let Students Derive, by Themselves, Two-Dimensional Atomic and Molecular Quantum Chemistry from Scratch

    ERIC Educational Resources Information Center

    Ge, Yingbin

    2016-01-01

    Hands-on exercises are designed for undergraduate physical chemistry students to derive two-dimensional quantum chemistry from scratch for the H atom and H[subscript 2] molecule, both in the ground state and excited states. By reducing the mathematical complexity of the traditional quantum chemistry teaching, these exercises can be completed…

  6. The Characteristics of an Antibacterial TiAgN Thin Film Coated by Physical Vapor Deposition Technique.

    PubMed

    Kang, Byeong-Mo; Jeong, Woon-Jo; Park, Gye-Choon; Yoon, Dong-Joo; Ahn, Ho-Geun; Lim, Yeong-Seog

    2015-08-01

    In this work, we found the characteristics of an antibacterial TiAgN thin film coated on the pure titanium specimen via the physical vapor deposition process (PVD). TiAgN thin films were coated using TiAg alloy targets by arc ion plating method. Changing the process parameters, the surface analysis of TiAgN thin film was observed by FE-SEM and the force of adhesion was measured with Scratch Tester. The proliferation of human gingival fibroblast (HGF) cells was examined by XTT test assay and the antibacterial properties were investigated by culturing Streptococus Mutans (KCTC 3065) using paper disk techniques. At the result of experiment, cytotoxic effects were not found and the antibacterial effects against Streptococus Mutans were appeared over 5 wt% TiAgN specimens.

  7. Library Programming with LEGO MINDSTORMS, Scratch, and PicoCricket: Analysis of Best Practices for Public Libraries

    ERIC Educational Resources Information Center

    Romero, Juan Suarez

    2010-01-01

    Public libraries are redefining their roles in order to stay relevant to the needs of the communities they serve. Today, libraries are places where reading meets hands-on learning and where quietness coexists with voices and music. The latest advances in technology for children and teens, specifically, robotics sets and media-rich software, are…

  8. An Analysis of Young Students' Thinking When Completing Basic Coding Tasks Using Scratch Jnr. on the iPad

    ERIC Educational Resources Information Center

    Falloon, G.

    2016-01-01

    Recent government moves in many countries have seen coding included in school curricula, or promoted as part of computing, mathematics or science programmes. While these moves have generally been associated with a need to engage more young people in technology study, research has hinted at possible benefits from learning to program including…

  9. Hard and flexible nanocomposite coatings using nanoclay-filled hyperbranched polymers.

    PubMed

    Fogelström, Linda; Malmström, Eva; Johansson, Mats; Hult, Anders

    2010-06-01

    The combination of hardness, scratch resistance, and flexibility is a highly desired feature in many coating applications. The aim of this study is to achieve this through the introduction of an unmodified nanoclay, montmorillonite (Na(+)MMT), in a polymer resin based on the hyperbranched polyester Boltorn H30. Smooth and transparent films were prepared from both the neat and the nanoparticle-filled hyperbranched resins. X-ray diffraction (XRD) and transmission electron microscopy (TEM) corroborated a mainly exfoliated structure in the nanocomposite films, which was also supported by results from dynamic mechanical analysis (DMA). Furthermore, DMA measurements showed a 9-16 degrees C increase in Tg and a higher storage modulus-above and below the T(g)-both indications of a more cross-linked network, for the clay-containing film. Thermogravimetric analysis (TGA) demonstrated the influence of the nanofiller on the thermal properties of the nanocomposites, where a shift upward of the decomposition temperature in oxygen atmosphere is attributed to the improved barrier properties of the nanoparticle-filled materials. Conventional coating characterization methods demonstrated an increase in the surface hardness, scratch resistance and flexibility, with the introduction of clay, and all coatings exhibited excellent chemical resistance and adhesion.

  10. Structure, adhesive strength and electrochemical performance of nitrogen doped diamond-like carbon thin films deposited via DC magnetron sputtering.

    PubMed

    Khun, N W; Liu, E; Krishna, M D

    2010-07-01

    Nitrogen doped diamond-like carbon (DLC:N) thin films were deposited on p-Si (100) substrates by DC magnetron sputtering with different nitrogen flow rates at a substrate temperature of about 100 degrees C. The chemical bonding structure of the films was characterized by X-ray photoelectron spectroscopy (XPS) and micro-Raman spectroscopy. The adhesive strength and surface morphology of the films were studied using micro-scratch tester and scanning electron microscope (SEM), respectively. The electrochemical performance of the films was evaluated by potentiodynamic polarization testing and linear sweep voltammetry. The electrolytes used for the electrochemical tests were deaerated and unstirred 0.47 M KCl aqueous solution for potentiodynamic polarization testing and 0.2 M KOH and 0.1 M KCl solutions for voltammetric analysis. It was found that the DLC:N films could well passivate the underlying substrates though the corrosion resistance of the films decreased with increased nitrogen content in the films. The DLC:N films showed wide potential windows in the KOH solution, in which the detection ability of the DLC:N films to trace lead of about 1 x 10(-3) M Pb(2+) was also tested.

  11. Scratch that itch: revisiting links between self-directed behaviour and parasitological, social and environmental factors in a free-ranging primate

    PubMed Central

    Romano, Valéria; MacIntosh, Andrew J. J.

    2016-01-01

    Different hypotheses explain variation in the occurrence of self-directed behaviour such as scratching and self-grooming: a parasite hypothesis linked with ectoparasite load, an environmental hypothesis linked with seasonal conditions and a social hypothesis linked with social factors. These hypotheses are not mutually exclusive but are often considered separately. Here, we revisited these hypotheses together in female Japanese macaques (Macaca fuscata fuscata) of Kōjima islet, Japan. We input occurrences of scratching and self-grooming during focal observations in models combining parasitological (lice load), social (dominance rank, social grooming, aggression received and proximity), and environmental (rainfall, temperature and season) variables. Using an information-theory approach, we simultaneously compared the explanatory value of models against each other using variation in Akaike's information criterion and Akaike's weights. We found that evidence for models with lice load, with or without environmental–social parameters, was stronger than that for other models. In these models, scratching was positively associated with lice load and social grooming whereas self-grooming was negatively associated with lice load and positively associated with social grooming, dominance rank and number of female neighbours. This study indicates that the study animals scratch primarily because of an immune/stimulus itch, possibly triggered by ectoparasite bites/movements. It also confirms that self-grooming could act as a displacement activity in the case of social uncertainty. We advocate that biological hypotheses be more broadly considered even when investigating social processes, as one does not exclude the other. PMID:28018646

  12. Diverse Clinical Signs of Ocular Involvement in Cat Scratch Disease.

    PubMed

    Oray, Merih; Önal, Sumru; Koç Akbay, Aylin; Tuğal Tutkun, İlknur

    2017-01-01

    To describe ocular manifestations, diagnosis, and treatment of cat scratch disease. Clinical records of patients with ocular cat scratch disease were reviewed. Thirteen eyes of 10 patients (7 female, 3 male) with a mean age of 26.9±18.5 years were included. Nine patients had a history of cat contact and had systemic symptoms associated with cat scratch disease 2-90 days prior to the ocular symptoms. Ocular signs were: neuroretinitis in 4 eyes (associated with serous retinal detachment in the inferior quadrant in 1 eye), optic neuropathy in 2 eyes (1 papillitis and optic disc infiltration, 1 optic neuritis), retinal infiltrates in 6 eyes, retinochoroiditis in 1 eye, branch retinal arteriolar occlusion in 3 eyes, and endophthalmitis in 1 eye. Visual acuities at presentation were 1.0 in 7 eyes, 0.3 in 1 eye, ≤0.1 in 4 eyes, and light perception in 1 eye. Bartonella henselae immunoglobulin (Ig) M and/or IgG were positive in all patients. Systemic antibiotic therapy was administered in all patients. Systemic corticosteroid treatment (15-40 mg/day) was added to the therapy in 4 patients, following 5 days of intravenous pulse methylprednisolone in 2 patients. Treatment was ongoing for 1 patient and the mean treatment duration of the other 9 patients was 47±14.5 days. Visual acuities at final visit were 1.0 in 9 eyes, 0.8 in 1 eye, 0.4 in 1 eye, and no light perception in 1 eye. Cat scratch disease may present with different ocular signs and should be considered in the differential diagnosis in patients with such presentations.

  13. Low-Temperature Self-Healing of a Microcapsule-Type Protective Coating

    PubMed Central

    Cho, Yu-Jin; Choi, Ju-Young; Kim, Beom-Jun; Jin, Seung-Won; Chung, Chan-Moon

    2017-01-01

    Low-temperature self-healing capabilities are essential for self-healing materials exposed to cold environments. Although low-temperature self-healing concepts have been proposed, there has been no report of a microcapsule-type low-temperature self-healing system wherein the healing ability was demonstrated at low temperature. In this work, low-temperature self-healing of a microcapsule-type protective coating was demonstrated. This system employed silanol-terminated polydimethylsiloxane (STP) as a healing agent and dibutyltin dilaurate (DD) as a catalyst. STP underwent a condensation reaction at −20 °C in the presence of DD to give a viscoelastic product. The reaction behavior of STP and the viscoelasticity of the reaction product were investigated. STP and DD were separately microencapsulated by in situ polymerization and interfacial polymerization methods, respectively. The STP- and DD-loaded microcapsules were mixed into a commercial enamel paint, and the resulting formulation was applied to glass slides, steel panels, and mortars to prepare self-healing coatings. When the self-healing coatings were damaged at a low temperature (−20 °C), STP and DD were released from broken microcapsules and filled the damaged area. This process was effectively visualized using a fluorescent dye. The self-healing coatings were scratched and subjected to corrosion tests, electrochemical tests, and saline solution permeability tests. The temperature of the self-healing coatings was maintained at −20 °C before and after scratching and during the tests. We successfully demonstrated that the STP/DD-based coating system has good low-temperature self-healing capability. PMID:28906465

  14. Ballistic impact resistance of selected organic ophthalmic lenses.

    PubMed

    Chou, B Ralph; Yuen, Gloria S-C; Dain, Stephen J

    2011-11-01

    The aim was to assess the impact resistance of coated and uncoated mid-index spectacle lens materials using the ballistic impact test. Nominally plano lenses of each material in three thicknesses were obtained. The lenses were flat edged to a 50 mm diameter. Each lens was impacted by a 6.35 mm steel ball. Impact velocities were selected using the Zippy Estimation by Sequential Testing protocol to determine the threshold fracture impact velocity. Threshold fracture impact velocity generally increased with thickness; however, there was a wide variation in performance among the various lens materials at each thickness. In all but two instances, the differences in impact velocity at each thickness of lens material were significant. Comparison of the data for CR39 and Hoya Phoenix with the results of earlier studies showed that the lens mounting is a significant factor. The fracture velocities found in the present study were significantly lower than the fracture velocities found when the lens edge is restrained in the mounting. A scratch resistant coating reduced the impact resistance of CR39. The effect of the antireflection coating on the fracture velocity depended on the nature of the base scratch-resistant coating. Mid-index lens materials of the same thickness show widely varying levels of impact resistance under the ballistic test. Impact resistance increases non-linearly with centre thickness. The lens mounting might affect the results of the ballistic impact test. The presence of 'cushion coatings' might enhance impact resistance. © 2011 The Authors. Clinical and Experimental Optometry © 2011 Optometrists Association Australia.

  15. B-mode sonographic criteria for differential diagnosis of cervicofacial lymphadenopathy in cat-scratch disease and toxoplasmosis.

    PubMed

    Ridder, Gerd Jürgen; Boedeker, Carsten Christof; Lee, Tao-Kwang Kevin; Sander, Anna

    2003-04-01

    Our purpose was to evaluate different sonographic parameters of cervicofacial lymphadenopathy caused by cat-scratch disease (CSD) and toxoplasmosis. By use of high-resolution B-mode sonography a total of 552 lymph nodes in the head and neck were detected between January 1997 and December 2001. There were 71 patients (422 lymph nodes) with CSD and 19 patients (130 lymph nodes) with toxoplasmosis. Sonographic variables, including 20 sonomorphologic features along with age and gender, were analyzed with multivariate logistic regression. Heterogenous lymph nodes were more often found in CSD (p =.003), and nonsharp nodal borders showed a significant association with CSD (p =.0005). Multivariate analysis identified sharpness of borders (p =.0001), S/L ratio (p =.0006), and type of lymphadenopathy (acute, abscessed, chronic) (p =.0006) as most significant for differentiating between CSD and toxoplasmosis. These results provide significant and useful criteria for ultrasonographic differentiation between CSD and toxoplasmosis. Copyright 2003 Wiley Periodicals, Inc.

  16. Deformation mechanism of CrN/nitriding coated steel in wear and nano-scratch experiments under heavy loading conditions

    NASA Astrophysics Data System (ADS)

    Wang, Yongguang; Chen, Yao; Zhao, Dong; Lu, Xiaolong; Liu, Weiwei; Qi, Fei; Chen, Yang

    2018-07-01

    CrN coatings are widely used to protect metals from wear in industrial engineering. However, fundamental deformation mechanism of these coatings under heavy loading conditions remains elusive. In this paper, multilayered hard coatings with a CrN matrix and a supporting layer were developed by means of the hybrid deposition process combined with PVD and ionicnitriding. The tribological behavior of coatings with and without ionicnitriding were investigated by a pin-on-disk arrangement under heavy loading conditions. In addition, the deformation mechanism of the multilayered hard coatings was studied by nano-scratch experiment with ramp load model, which has not been discussed previously. It was found that the deformation process of coatings could be divided into three regimes based on the evolution of frictional coefficient. The insertion of nitriding films leads to the further increase in frictional resistance owing to the elastic-plastic deformation. The results and analysis reveal some insights into the coating design for multilayered hard coatings with the consideration of deformation mechanisms.

  17. Synthesis and characterization of curcumin loaded PLA-Hyperbranched polyglycerol electrospun blend for wound dressing applications.

    PubMed

    Perumal, Govindaraj; Pappuru, Sreenath; Chakraborty, Debashis; Maya Nandkumar, A; Chand, Dillip Kumar; Doble, Mukesh

    2017-07-01

    This study is aimed to develop curcumin (Cur) incorporated electrospun nanofibers of a blend of poly (lactic acid) (PLA) and hyperbranched polyglycerol (HPG) for wound healing applications. Both the polymers are synthesized and fabricated by electrospinning technique. The produced nanofibers were characterized by Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Colorimetry (DSC) and Thermogravimetric Analysis (TGA). Electrospun scaffolds (PLA/HPG/Cur) exhibits very high hydrophilicity, high swelling and drug uptake and promotes better cell viability, adhesion and proliferation when compared to PLA/Cur electrospun nanofibers. Biodegradation study revealed that the morphology of the nanofibers were unaffected even after 14days immersion in Phosphate Buffered Saline. In vitro scratch assay indicates that migration of the cells in the scratch treated with PLA/HPG/Cur is complete within 36h. These results suggest that PLA/HPG/Cur nanofibers can be a potential wound patch dressing for acute and chronic wound applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. TiO2 nanotubes and mesoporous silica as containers in self-healing epoxy coatings

    PubMed Central

    Vijayan P., Poornima; Al-Maadeed, Mariam Ali S. A.

    2016-01-01

    The potential of inorganic nanomaterials as reservoirs for healing agents is presented here. Mesoporous silica (SBA-15) and TiO2 nanotubes (TNTs) were synthesized. Both epoxy-encapsulated TiO2 nanotubes and amine-immobilized mesoporous silica were incorporated into epoxy and subsequently coated on a carbon steel substrate. The encapsulated TiO2 nanotubes was quantitatively estimated using a ‘dead pore ratio’ calculation. The morphology of the composite coating was studied in detail using transmission electron microscopic (TEM) analysis. The self-healing ability of the coating was monitored using electrochemical impedance spectroscopy (EIS); the coating recovered 57% of its anticorrosive property in 5 days. The self-healing of the scratch on the coating was monitored using Scanning Electron Microscopy (SEM). The results confirmed that the epoxy pre-polymer was slowly released into the crack. The released epoxy pre-polymer came into contact with the amine immobilized in mesoporous silica and cross-linked to heal the scratch. PMID:27941829

  19. [Tetanus after cat scratch and bites in a previously immunized patient].

    PubMed

    Fica, Alberto; Gaínza, Daniela; Ortigosa, Pablo

    2017-04-01

    Tetanus is declining due to vaccination, professional labor management and appropriate wound care. Tetanus cases have been reported despite immunization. We report the case of a previously healthy 21 years old female patient that presented a mild generalized tetanus requiring admission after mild and recurrent cat scratch and bites. She had received six vaccine shots during childhood, and a booster dose five years earlier after a rabbit bite. Symptoms appeared seven weeks after the last contact, and included headache, muscle spasms and mild opisthotonus. Laboratory evaluation, including CSF analysis and microbiological investigation, as well as imaging studies were all normal. The patient received 6,000 IU of human antitoxin immunoglobulin. No autonomic manifestations or respiratory compromise were registered. Symptoms resolved rapidly and she was discharge after seven days with an order to complete a tetanus toxoid immunization schedule with three doses. Tetanus is possible in urban settings with a declining epidemiologic curve of disease in previously immunized patients. Severity of disease is modulated by previous vaccination.

  20. Evaluation of the LiveWell@School Food Initiative Shows Increases in Scratch Cooking and Improvement in Nutritional Content

    ERIC Educational Resources Information Center

    Schober, Daniel J.; Carpenter, Leah; Currie, Venita; Yaroch, Amy L.

    2016-01-01

    Background: The purpose of this evaluation was to examine the effects of the LiveWell@School Food Initiative (LW@SFI), a Colorado-based childhood obesity prevention program that partners with school districts to enable them to serve more scratch cooked foods through culinary training, action planning, and equipment grants. Methods: This evaluation…

  1. How Not to Strike it Rich: Semantics, Pragmatics, and Semiotics of a Massachusetts Lottery Game Card

    ERIC Educational Resources Information Center

    Butters, Ronald R.

    2004-01-01

    In 2001, the Massachusetts State Lottery Commission released for sale a new "instant lottery ticket" "scratch-and-play" game card named "Caesars [sic] Palace[R]" (played by scratching the surface of each card at designated spots to reveal hidden numbers or images). It offered ten grand prizes of $1,000,000 each and a…

  2. The Programmers' Collective: Fostering Participatory Culture by Making Music Videos in a High School Scratch Coding Workshop

    ERIC Educational Resources Information Center

    Fields, Deborah; Vasudevan, Veena; Kafai, Yasmin B.

    2015-01-01

    We highlight ways to support interest-driven creation of digital media in Scratch, a visual-based programming language and community, within a high school programming workshop. We describe a collaborative approach, the programmers' collective, that builds on social models found in do-it-yourself and open source communities, but with scaffolding…

  3. Contagious itch: what we know and what we would like to know

    PubMed Central

    Schut, C.; Grossman, S.; Gieler, U.; Kupfer, J.; Yosipovitch, G.

    2015-01-01

    All humans experience itch in the course of their life. Even a discussion on the topic of itch or seeing people scratch can evoke the desire to scratch. These events are coined “contagious itch” and are very common. We and others have shown that videos showing people scratching and pictures of affected skin or insects can induce itch in healthy persons and chronic itch patients. In our studies, patients with atopic dermatitis (AD) were more susceptible to visual itch cues than healthy. Also, personality traits like agreeableness and public self-consciousness were associated with induced scratching in skin patients, while neuroticism correlated with induced itch in healthy subjects. The underlying course of contagious itch is not yet fully understood. It is hypothesized that there are human mirror neurons that are active when we imitate actions and/or negative affect. Until now, there has been only limited data on the mechanisms of brain activation in contagious itch though. We have barely begun to understand the underlying physiological reactions and the triggering factors of this phenomenon. We summarize what we currently know about contagious itch and provide some suggestions what future research should focus on. PMID:25717300

  4. Tuning the Mechanical and Antimicrobial Performance of a Cu-Based Metallic Glass Composite through Cooling Rate Control and Annealing.

    PubMed

    Villapún, Victor M; Esat, F; Bull, S; Dover, L G; González, S

    2017-05-06

    The influence of cooling rate on the wear and antimicrobial performance of a Cu 52 Z 41 Al₇ (at. %) bulk metallic glass (BMG) composite was studied and the results compared to those of the annealed sample (850 °C for 48 h) and to pure copper. The aim of this basic research is to explore the potential use of the material in preventing the spread of infections. The cooling rate is controlled by changing the mould diameter (2 mm and 3 mm) upon suction casting and controlling the mould temperature (chiller on and off). For the highest cooling rate conditions CuZr is formed but CuZr₂ starts to crystallise as the cooling rate decreases, resulting in an increase in the wear resistance and brittleness, as measured by scratch tests. A decrease in the cooling rate also increases the antimicrobial performance, as shown by different methodologies (European, American and Japanese standards). Annealing leads to the formation of new intermetallic phases (Cu 10 Zr₇ and Cu₂ZrAl) resulting in maximum scratch hardness and antimicrobial performance. However, the annealed sample corrodes during the antimicrobial tests (within 1 h of contact with broth). The antibacterial activity of copper was proved to be higher than that of any of the other materials tested but it exhibits very poor wear properties. Cu-rich BMG composites with optimised microstructure would be preferable for some applications where the durability requirements are higher than the antimicrobial needs.

  5. Occupational health hazards in veterinary medicine: Zoonoses and other biological hazards

    PubMed Central

    Epp, Tasha; Waldner, Cheryl

    2012-01-01

    This study describes biological hazards reported by veterinarians working in western Canada obtained through a self-administered mailed questionnaire. The potential occupational hazards included as biological hazards were zoonotic disease events, exposure to rabies, injuries due to bites and scratches, and allergies. Only 16.7% (136/812) of responding veterinarians reported the occurrence of a zoonosis or exposure to rabies in the past 5 years; the most commonly reported event was ringworm. Most bites and scratches (86%) described by 586 veterinarians involved encounters with cats; 81% of the resulting 163 infections were due to cat bites or scratches. Approximately 38% of participants reported developing an allergy during their career, with 41% of the affected individuals altering the way they practiced in response to their allergy. PMID:22851775

  6. Development of a Detonation Diffuser

    DTIC Science & Technology

    2014-03-27

    detonation frequency is adjustable from 8 Hz to 40 Hz, and the ignition can be set to operate in “burst mode” firing for a predetermined number of cycles... resistance were tried, but the strain on the windows caused the coating to fracture. Without a scratch- resistant coating, the windows regularly suffered... abrasion from the Shock wave Strain waves 35 test articles. The heat from local explosions did burn away a small amount of the window surface

  7. Collaborative Research and Development (CR&D). Task Order 0049: Tribological Modeling

    DTIC Science & Technology

    2008-05-01

    scratch test for TiN on stainless steel with better substrate mechanical properties. This present study was focused on the study of stress distribution...AFRL-RX-WP-TR-2010-4189 COLLABORATIVE RESEARCH AND DEVELOPMENT (CR&D) Task Order 0049: Tribological Modeling Young Sup Kang Universal...SUBTITLE COLLABORATIVE RESEARCH AND DEVELOPMENT (CR&D) Task Order 0049: Tribological Modeling 5a. CONTRACT NUMBER F33615-03-D-5801-0049 5b

  8. Exploring Deep Learning and Transfer Learning for Colonic Polyp Classification

    PubMed Central

    Uhl, Andreas; Wimmer, Georg; Häfner, Michael

    2016-01-01

    Recently, Deep Learning, especially through Convolutional Neural Networks (CNNs) has been widely used to enable the extraction of highly representative features. This is done among the network layers by filtering, selecting, and using these features in the last fully connected layers for pattern classification. However, CNN training for automated endoscopic image classification still provides a challenge due to the lack of large and publicly available annotated databases. In this work we explore Deep Learning for the automated classification of colonic polyps using different configurations for training CNNs from scratch (or full training) and distinct architectures of pretrained CNNs tested on 8-HD-endoscopic image databases acquired using different modalities. We compare our results with some commonly used features for colonic polyp classification and the good results suggest that features learned by CNNs trained from scratch and the “off-the-shelf” CNNs features can be highly relevant for automated classification of colonic polyps. Moreover, we also show that the combination of classical features and “off-the-shelf” CNNs features can be a good approach to further improve the results. PMID:27847543

  9. Microstructural design of functionally graded coatings composed of suspension plasma sprayed hydroxyapatite and bioactive glass.

    PubMed

    Cattini, Andrea; Bellucci, Devis; Sola, Antonella; Pawłowski, Lech; Cannillo, Valeria

    2014-04-01

    Various bioactive glass/hydroxyapatite (HA) functional coatings were designed by the suspension plasma spraying (SPS) technique. Their microstructure, scratch resistance, and apatite-forming ability in a simulated body fluid (SBF) were compared. The functional coatings design included: (i) composite coating, that is, randomly distributed constituent phases; (ii) duplex coating with glass top layer onto HA layer; and (iii) graded coating with a gradual changing composition starting from pure HA at the interface with the metal substrate up to pure glass on the surface. The SPS was a suitable coating technique to produce all the coating designs. The SBF tests revealed that the presence of a pure glass layer on the working surface significantly improved the reactivity of the duplex and graded coatings, but the duplex coating suffered a relatively low scratch resistance because of residual stresses. The graded coating therefore provided the best compromise between mechanical reliability and apatite-forming ability in SBF. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 551-560, 2014. Copyright © 2013 Wiley Periodicals, Inc.

  10. Rabies-Related Knowledge and Practices Among Persons At Risk of Bat Exposures in Thailand

    PubMed Central

    Robertson, Kis; Lumlertdacha, Boonlert; Franka, Richard; Petersen, Brett; Bhengsri, Saithip; Henchaichon, Sununta; Peruski, Leonard F.; Baggett, Henry C.; Maloney, Susan A.; Rupprecht, Charles E.

    2011-01-01

    Background Rabies is a fatal encephalitis caused by lyssaviruses. Evidence of lyssavirus circulation has recently emerged in Southeast Asian bats. A cross-sectional study was conducted in Thailand to assess rabies-related knowledge and practices among persons regularly exposed to bats and bat habitats. The objectives were to identify deficiencies in rabies awareness, describe the occurrence of bat exposures, and explore factors associated with transdermal bat exposures. Methods A survey was administered to a convenience sample of adult guano miners, bat hunters, game wardens, and residents/personnel at Buddhist temples where mass bat roosting occurs. The questionnaire elicited information on demographics, experience with bat exposures, and rabies knowledge. Participants were also asked to describe actions they would take in response to a bat bite as well as actions for a bite from a potentially rabid animal. Bivariate analysis was used to compare responses between groups and multivariable logistic regression was used to explore factors independently associated with being bitten or scratched by a bat. Findings Of 106 people interviewed, 11 (10%) identified bats as a potential source of rabies. A history of a bat bite or scratch was reported by 29 (27%), and 38 (36%) stated either that they would do nothing or that they did not know what they would do in response to a bat bite. Guano miners were less likely than other groups to indicate animal bites as a mechanism of rabies transmission (68% vs. 90%, p = 0.03) and were less likely to say they would respond appropriately to a bat bite or scratch (61% vs. 27%, p = 0.003). Guano mining, bat hunting, and being in a bat cave or roost area more than 5 times a year were associated with history of a bat bite or scratch. Conclusions These findings indicate the need for educational outreach to raise awareness of bat rabies, promote exposure prevention, and ensure appropriate health-seeking behaviors for bat-inflicted wounds, particularly among at-risk groups in Thailand. PMID:21738801

  11. Periostin promotes migration and osteogenic differentiation of human periodontal ligament mesenchymal stem cells via the Jun amino-terminal kinases (JNK) pathway under inflammatory conditions.

    PubMed

    Tang, Yi; Liu, Lin; Wang, Pei; Chen, Donglei; Wu, Ziqiang; Tang, Chunbo

    2017-12-01

    Mesenchymal stem cell (MSC)-mediated periodontal tissue regeneration is considered to be a promising method for periodontitis treatment. The molecular mechanism of functional regulation by MSCs remains unclear, thus limiting their application. Our previous study discovered that Periostin (POSTN) promoted the migration and osteogenic differentiation of periodontal ligament mesenchymal stem cells (PDLSCs), but it is still unclear whether POSTN is able to restore the regenerative potential of PDLSCs under inflammatory conditions. In this study, we investigated the effect of POSTN on PDLSCs under inflammatory conditions and its mechanism. PDLSCs were isolated from periodontal ligament tissue. TNF-α was used at 10 ng/mL to mimic inflammatory conditions. Lentivirus POSTN shRNA was used to knock down POSTN. Recombinant human POSTN (rhPOSTN) was used to stimulate PDLSCs. A scratch assay was used to analyse cell migration. Alkaline phosphatase (ALP) activity, Alizarin Red staining and expression of osteogenesis-related genes were used to investigate the osteogenic differentiation potential. Western blot analysis was used to detect the mitogen-activated protein kinases (MAPK) and AKT signalling pathways. After a 10 ng/mL TNF-α treatment, knockdown of POSTN impeded scratch closure, inhibited ALP activity and mineralization in vitro, and decreased expression of RUNX2, OSX, OPN and OCN in PDLSCs, while 75 ng/mL rhPOSTN significantly accelerated scratch closure, enhanced ALP activity and mineralization in vitro, and increased expression of RUNX2, OSX, OPN and OCN. In addition, knockdown of POSTN inhibited expression of phosphorylated c-Jun N-terminal kinase (p-JNK), while 75 ng/mL rhPOSTN increased expression of p-JNK in PDLSCs with TNF-α treatment. Furthermore, inhibition of JNK by its inhibitor SP600125 dramatically blocked POSTN-enhanced scratch closure, ALP activity and mineralization in PDLSCs. Our results revealed that POSTN might promote the migration and osteogenic differentiation potential of PDLSCs via the JNK pathway, providing insight into the mechanism underlying MSC biology under inflammatory conditions and identifying a potential target for improving periodontal tissue regeneration. © 2017 John Wiley & Sons Ltd.

  12. Circumcision and Reduced Risk of Self-Reported Penile Coital Injuries: Results from a Randomized Controlled Trial in Kisumu, Kenya

    PubMed Central

    Mehta, Supriya D.; Krieger, John N.; Agot, Kawango; Moses, Stephen; Ndinya-Achola, Jeckoniah O.; Parker, Corette; Bailey, Robert C.

    2011-01-01

    Purpose Injuries to the penis during intercourse represent one hypothesized mechanism by which uncircumcised men are at increased risk for HIV. There are no published, systematically collected data regarding mild penile coital trauma. We identified risks for self-reported penile coital injuries in men aged 18–24 in our randomized trial of circumcision to prevent HIV in Kisumu, Kenya. Materials and Methods Each participant underwent standardized interview, medical history, and physical examination, at baseline and 6, 12, 18, and 24 months after enrollment. Self-reported penile coital injuries were assessed at each visit: penis feels sore during sex; penis gets scratches, cuts or abrasions during sex; skin of the penis bleeds after sex. Generalized estimating equation analysis estimated odds ratios (OR) for penile coital injuries. Results February 2002–September 2005, 2,784 participants were randomized. At baseline, 1,775 (64.4%) men reported any coital injury: 1,313 (47.6%) soreness; 1,328 (48.2%) scratches, abrasions, or cuts; 461 (16.7%) bleeding. In multivariable analysis, coital injury risk was lower for circumcised than uncircumcised men: soreness [OR=0.71, 95% CI 0.64–0.80], scratches/abrasions/cuts [OR=0.52, 95% CI 0.46–0.59], bleeding [OR=0.62, 95% CI 0.51–0.75], any coital injury [OR=0.61, 95% CI 0.54–0.68]. Other significant risks (p<0.05) included: increasing age, multiple recent sex partners, HSV-2 seropositivity, and genital ulcers. Condom use, cleaning the penis soon after intercourse, and being married/cohabiting were protective (p<0.05, each). Conclusions Self-reported penile coital injuries were common in these healthy young men. Circumcised men were at lower risk for coital injuries. Verifying penile coital injuries, mechanism of acquisition, and association with HIV risk is needed. PMID:20483156

  13. Clinical characteristics in 53 patients with cat scratch optic neuropathy.

    PubMed

    Chi, Sulene L; Stinnett, Sandra; Eggenberger, Eric; Foroozan, Rod; Golnik, Karl; Lee, Michael S; Bhatti, M Tariq

    2012-01-01

    To describe the clinical manifestations and to identify risk factors associated with visual outcome in a large cohort of patients with cat scratch optic neuropathy (CSON). Multicenter, retrospective chart review. Fifty-three patients (62 eyes) with serologically positive CSON from 5 academic neuro-ophthalmology services evaluated over an 11-year period. Institutional review board/ethics committee approval was obtained. Data from medical record charts were collected to detail the clinical manifestations and to analyze visual outcome metrics. Generalized estimating equations and logistic regression analysis were used in the statistical analysis. Six patients (9 eyes) were excluded from visual outcome statistical analysis because of a lack of follow-up. Demographic information, symptoms at presentation, clinical characteristics, length of follow-up, treatment used, and visual acuity (at presentation and final follow-up). Mean patient age was 27.8 years (range, 8-65 years). Mean follow-up time was 170.8 days (range, 1-1482 days). Simultaneous bilateral involvement occurred in 9 (17%) of 53 patients. Visual acuity on presentation ranged from 20/20 to counting fingers (mean, 20/160). Sixty-eight percent of eyes retained a visual acuity of 20/40 or better at final follow-up (defined as favorable visual outcome). Sixty-seven percent of patients endorsed a history of cat or kitten scratch. Neuroretinitis (macular star) developed in 28 eyes (45%). Only 5 patients had significant visual complications (branch retinal artery occlusion, macular hole, and corneal decompensation). Neither patient age nor any other factor except good initial visual acuity and absence of systemic symptoms was associated with a favorable visual outcome. There was no association between visual acuity at final follow-up and systemic antibiotic or steroid use. Patients with CSON have a good overall visual prognosis. Good visual acuity at presentation was associated with a favorable visual outcome. The absence of a macular star does not exclude the possibility of CSON. The author(s) have no proprietary or commercial interest in any materials discussed in this article. Copyright © 2012 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  14. Atypical manifestation of cat-scratch disease: isolated epigastric pain in an immunocompetent, 12-year-old child.

    PubMed

    Kayemba-Kay's, Simon; Kovács, Tamas; Rakotoharinandrasana, Iarolalao; Benosman, Sidi Mohamed

    2015-07-01

    We present a 12-year-old immunocompetent girl with hepato splenic cat-scratch disease (CSD). Her sole inaugural complaint was isolated epigastric pain. She fully recovered, with normalized abdominal CT scan following 2 weeks course of Azythromycin®. CSD should be included in differential diagnosis in children with epigastric pain, especially in those with domestic pets.

  15. Scanning micro-sclerometer

    DOEpatents

    Oliver, W.C.; Blau, P.J.

    1994-11-01

    A scanning micro-sclerometer measures changes in contact stiffness and correlates these changes to characteristics of a scratch. A known force is applied to a contact junction between two bodies and a technique employing an oscillating force is used to generate the contact stiffness between the two bodies. As the two bodies slide relative to each other, the contact stiffness changes. The change is measured to characterize the scratch. 2 figs.

  16. Corticosteroid Treatment for Prolonged Fever in Hepatosplenic Cat-Scratch Disease: A Case Study.

    PubMed

    Phan, Amanda; Castagnini, Luis A

    2017-12-01

    Hepatosplenic cat-scratch disease (CSD) may cause prolonged fever. We present the case of a 4-year-old boy with confirmed hepatosplenic CSD with fever lasting 3 months despite use of multiple different antimicrobial agents. The patient became afebrile soon after corticosteroid therapy was started. Our case indicates corticosteroids may be useful in patients with hepatosplenic CSD and prolonged fever.

  17. Scanning micro-sclerometer

    DOEpatents

    Oliver, Warren C.; Blau, Peter J.

    1994-01-01

    A scanning micro-sclerometer measures changes in contact stiffness and correlates these changes to characteristics of a scratch. A known force is applied to a contact junction between two bodies and a technique employing an oscillating force is used to generate the contact stiffness between the two bodies. As the two bodies slide relative to each other, the contact stiffness changes. The change is measured to characterize the scratch.

  18. A method to induce stable atopic dermatitis-like symptoms in NC/Nga mice housed with skin-lesioned mice.

    PubMed

    Takano, N; Arai, I; Kurachi, M

    2006-03-01

    Itching is a characteristic symptom in various forms of dermatosis, especially atopic dermatitis; consequently it is a major diagnostic criterion. All features are similar to events seen in patients, hence NC/Nga mice are considered to be a suitable model of human atopic dermatitis. However, there were data spreads in commencing time and the degree of skin lesions in NC/Nga mice. In the present study, we attempted to improve experimental conditions to induce stable skin lesions and to establish a more appropriate method. Methods NC/Nga mice were kept together with skin-lesioned mice during the experiment period (mixed-NC mice). The dermatitis scores of face, ears and rostral back were assessed. Scratching behaviour was measured using an apparatus, MicroAct (Neuroscience, Tokyo, Japan). Transepidermal water loss (TEWL) and serum total IgE levels were also measured. To observe the presence of mites, the skin of the rostral backs of the mixed-NC mice was stripped using cellulose tape. We also investigated the effects of fipronil (Wako, Osaka, Japan), an acaricidal compound, on skin lesions and scratching behaviour of these mixed-NC mice. In mixed-NC mice, skin lesions appeared from 2 weeks, worsened gradually and reached peak levels of a dermatitis score in 8 weeks. Scratching behaviour increased significantly from day 3. TEWL also increased from day 3, but total IgE increased from day 7. Mites were observed on the rostral backs of mixed-NC mice from day 3, and all mice had these mites on day 28. Giving pretreatment with fipronil (Wako), the skin lesions and scratching behaviour of mixed-NC mice was significantly suppressed. The findings of the present study suggest that the method of being kept together with skin-lesioned mice can induce stable skin lesions and scratching behaviour at an early stage, without skin lesions. This method could help investigate a more stable evaluation of the effects on symptoms of atopic dermatitis, and mechanisms of the itching. It was considered that parasitism of mites, not allergic reactions, was the pathogenesis of skin lesions and scratching behaviour in mixed-NC mice.

  19. Public perceptions of cooking and the implications for cooking behaviour in the USA.

    PubMed

    Wolfson, Julia A; Smith, Katherine Clegg; Frattaroli, Shannon; Bleich, Sara N

    2016-06-01

    Despite the importance of cooking in modern life, public perceptions about what it means to cook are unknown. We aimed to examine perceptions of cooking and their association with cooking confidence, attitudes and behaviours in the USA. We designed and fielded a nationally representative survey among US adults (n 1112) in April 2015. We used factor analysis to identify perceptions about cooking and multivariate ordered logit and Poisson models to explore associations between those perceptions and cooking confidence, attitudes and behaviours. Nationally representative web-based survey of US adults. US adults aged ≥18 years. Americans conceptualized cooking in three ways: the use of scratch ingredients, convenience foods and not using heat. Respondents who perceived cooking as including convenience foods were less confident in their ability to cook from scratch (OR=0·52, P<0·001) and less likely to enjoy cooking (OR=0·68, P=0·01) than those who did not. Although individuals who perceived cooking as including only scratch ingredients reported cooking dinner (4·31 times/week) and using packaged/boxed products (0·95 times/week) the least frequently, few notable differences in the frequency of cooking meals were observed. Cooking frequency is similar among US adults regardless of how they perceive cooking, but cooking confidence and enjoyment are lowest among Americans who perceive cooking as including the use of convenience foods. These insights should inform the development of more specific measures of cooking behaviour as well as meaningful and targeted public health messages to encourage healthier cooking.

  20. Benefits of utilizing CellProfiler as a characterization tool for U-10Mo nuclear fuel

    DOE PAGES

    Collette, R.; Douglas, J.; Patterson, L.; ...

    2015-05-01

    Automated image processing techniques have the potential to aid in the performance evaluation of nuclear fuels by eliminating judgment calls that may vary from person-to-person or sample-to-sample. Analysis of in-core fuel performance is required for design and safety evaluations related to almost every aspect of the nuclear fuel cycle. This study presents a methodology for assessing the quality of uranium-molybdenum fuel images and describes image analysis routines designed for the characterization of several important microstructural properties. The analyses are performed in CellProfiler, an open-source program designed to enable biologists without training in computer vision or programming to automatically extract cellularmore » measurements from large image sets. The quality metric scores an image based on three parameters: the illumination gradient across the image, the overall focus of the image, and the fraction of the image that contains scratches. The metric presents the user with the ability to ‘pass’ or ‘fail’ an image based on a reproducible quality score. Passable images may then be characterized through a separate CellProfiler pipeline, which enlists a variety of common image analysis techniques. The results demonstrate the ability to reliably pass or fail images based on the illumination, focus, and scratch fraction of the image, followed by automatic extraction of morphological data with respect to fission gas voids, interaction layers, and grain boundaries.« less

  1. Ground scratching and preferred leg use in domestic chicks: changes in motor control in the first two weeks post-hatching.

    PubMed

    Dharmaretnam, Meena; Vijitha, V; Priyadharshini, K; Jashini, T; Vathany, K

    2002-10-01

    Lateralisation of a variety of visual functions: food discrimination, fear response, copulation, and performance of topographical and other tasks, such as olfactory and auditory functions, have been described in the domestic chick, Gallus gallus domesticus. A bias to left hemisphere control on day 8 and to the right on day 11 has also been demonstrated in the domestic chick. In this study we show that motor control as to foot preference in initiating a scratching bout and a tape-removing task is lateralised in both adults and chicks. There was a preference for the right leg to initiate a bout of ground scratching in both male and female adult birds. Second, foot preference is also affected by the changes in shifts of bias on day 8 and day 11. The right leg preference in initiating a ground scratching bout observed on day 5 is reversed to a left leg preference on day 8. This then reverts to the right leg preference after day 11. Hence it is postulated that the hemisphere that is not activated due to the bias of age controls the first leg to be used in initiating routine movements such as ground scratching. For the tape-removing task the right leg was used to remove a tape adhered to the beak of the chick for the trained group on day 8; but there was no preference in the naive group. Similarly, on day 11 a left foot bias was observed for the trained group and right foot bias for the naive group. To remove a tape the activated hemisphere on days of bias is used; whereas in a novel situation the foot use is reversed. Thus, footedness is affected by age, type of task, and changing hemispheric dominance.

  2. The effect of the plasma needle on the human keratinocytes related to the wound healing process

    NASA Astrophysics Data System (ADS)

    Korolov, Ihor; Fazekas, Barbara; Széll, Márta; Kemény, Lajos; Kutasi, Kinga

    2016-01-01

    In the present study we aim to verify the influence of a non-thermal atmospheric pressure plasma on the wound healing process. In this process the major contributors are the keratinocytes, which migrate to fill in the gap created by the wound. Therefore, we performed the direct treatment of HPV-immortalized human keratinocytes, protected by a layer of phosphate buffered saline (PBS) solution, with the glow discharge generated in flowing helium by a plasma needle. To mimick a wound, a 4 mm scratch was performed on the cell culture (scratch assay). We conducted two types of experiments: (i) cell proliferation and (ii) wound-healing model experiments. The plasma needle configuration, the plasma treatment conditions and the thickness of the protecting PBS layer were set based on viability experiments. The proliferation studies showed that short, 5-10 s, and low power treatments, such as 18 W and 20 W input power, could positively influence the cell proliferation when keratinocytes were protected by PBS. On the other hand, the plasma treatment of cell medium covered keratinocytes resulted in the decrease of proliferation. The wound-healing model (scratch assay) studies showed, that there was a maximum in the wound reduction as a function of the input power and treatment time, namely, at 18 W and 5 s. Furthermore, the wound reduction strongly depended on the treated cell—PBS interaction time. To mimic an infected wound, the scratch assay was covered with a 1× {{10}9} cfu ml-1 Propionibacterium acnes suspension. The plasma treatment of this infected assay resulted in closing of the scratch, while in the non-treated assay the wound did not close at all.

  3. Fetal Fibroblasts and Keratinocytes with Immunosuppressive Properties for Allogeneic Cell-Based Wound Therapy

    PubMed Central

    Zuliani, Thomas; Saiagh, Soraya; Knol, Anne-Chantal; Esbelin, Julie; Dréno, Brigitte

    2013-01-01

    Fetal skin heals rapidly without scar formation early in gestation, conferring to fetal skin cells a high and unique potential for tissue regeneration and scar management. In this study, we investigated the possibility of using fetal fibroblasts and keratinocytes to stimulate wound repair and regeneration for further allogeneic cell-based therapy development. From a single fetal skin sample, two clinical batches of keratinocytes and fibroblasts were manufactured and characterized. Tolerogenic properties of the fetal cells were investigated by allogeneic PBMC proliferation tests. In addition, the potential advantage of fibroblasts/keratinocytes co-application for wound healing stimulation has been examined in co-culture experiments with in vitro scratch assays and a multiplex cytokines array system. Based on keratin 14 and prolyl-4-hydroxylase expression analyses, purity of both clinical batches was found to be above 98% and neither melanocytes nor Langerhans cells could be detected. Both cell types demonstrated strong immunosuppressive properties as shown by the dramatic decrease in allogeneic PBMC proliferation when co-cultured with fibroblasts and/or keratinocytes. We further showed that the indoleamine 2,3 dioxygenase (IDO) activity is required for the immunoregulatory activity of fetal skin cells. Co-cultures experiments have also revealed that fibroblasts-keratinocytes interactions strongly enhanced fetal cells secretion of HGF, GM-CSF, IL-8 and to a lesser extent VEGF-A. Accordingly, in the in vitro scratch assays the fetal fibroblasts and keratinocytes co-culture accelerated the scratch closure compared to fibroblast or keratinocyte mono-cultures. In conclusion, our data suggest that the combination of fetal keratinocytes and fibroblasts could be of particular interest for the development of a new allogeneic skin substitute with immunomodulatory activity, acting as a reservoir for wound healing growth factors. PMID:23894651

  4. DJ Sim: a virtual reality DJ simulation game

    NASA Astrophysics Data System (ADS)

    Tang, Ka Yin; Loke, Mei Hwan; Chin, Ching Ling; Chua, Gim Guan; Chong, Jyh Herng; Manders, Corey; Khan, Ishtiaq Rasool; Yuan, Miaolong; Farbiz, Farzam

    2009-02-01

    This work describes the process of developing a 3D Virtual Reality (VR) DJ simulation game intended to be displayed on a stereoscopic display. Using a DLP projector and shutter glasses, the user of the system plays a game in which he or she is a DJ in a night club. The night club's music is playing, and the DJ is "scratching" in correspondence to this music. Much in the flavor of Guitar Hero or Dance Dance Revolution, a virtual turntable is manipulated to project information about how the user should perform. The user only needs a small set of hand gestures, corresponding to the turntable scratch movements to play the game. As the music plays, a series of moving arrows approaching the DJ's turntable instruct the user as to when and how to perform the scratches.

  5. A study of material removal during magnetorheological finishing. 1998 summer research program for high school juniors at the Univ. of Rochester`s Laboratory for Laser Energetics: Student research reports

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

    Hubregsen, J.

    1999-03-01

    In the process of optical polishing, a new method has been developed called Magnetorheological Finishing, or MRF. This process utilizes both mechanical and chemical effects to remove material during polishing. To more fully understand the fundamental mechanisms of MR polishing the authors have successfully separated mechanical scratching from chemical softening in glass polishing with MRF by removing the water from the MR fluid. The addition of water initiates the chemical effects by hydrating the glass surface and changing the amplitude of the scratches. In addition, this study has found that the mechanical removal by scratching is related to the hardnessmore » of the magnetic carbonyl iron particles, and the hardness and type of the glass being polished.« less

  6. A case of cat-scratch disease with unusual ophthalmic manifestations.

    PubMed

    Ghazi, Nicola G; Sams, Waler A

    2012-01-01

    We report a case of cat-scratch disease with unusual posterior segment manifestations. A 12-year-old healthy male presented with three weeks history of decreased visual acuity in the right eye. A significant history of cat exposure and elevated Bartonella titers were present. A large white-gray vascularized mass extending off the optic disk, an early stellate maculopathy, a plaque of choroiditis, an inferior serous retinal detachment involving the macula were present in the right eye. Sector papillitis and a focal area of chorioretinitis along the superotemporal arcade with associated retinal artery to vein anastomosis were present in the left eye. Bilateral optic nerve head involvement including peripapillary angiomatosis, retinal-retinal anastomosis and plaque choroiditis as ocular complications of cat-scratch disease have not been previously described to our knowledge and make this case noteworthy.

  7. Kinetics and Tribological Characterization of Pack-Borided AISI 1025 Steel

    NASA Astrophysics Data System (ADS)

    Gómez-Vargas, O. A.; Keddam, M.; Ortiz-Domínguez, M.

    2017-03-01

    In this present study, the AISI 1025 steel was pack-borided in the temperature range of 1,123-1,273 K for different treatment times ranging from 2 to 8 h. A diffusion model was suggested to estimate the boron diffusion coefficients in the Fe2B layers. As a result, the boron activation energy for the AISI 1025 steel was estimated as 174.36 kJ/mol. This value of energy was compared with the literature data. To extend the validity of the present model, other additional boriding conditions were considered. The boride layers formed on the AISI 1025 steel were characterized by the following experimental techniques: scanning electron microscopy, X-ray diffraction analysis and the Daimler-Benz Rockwell-C indentation technique. Finally, the scratch and pin-on-disc tests for wear resistance were achieved using an LG Motion Ltd and a CSM tribometer, respectively, under dry sliding conditions.

  8. Comments on Cadmium Alternatives and Testing - IHE vs. EHE (Briefing Charts)

    DTIC Science & Technology

    2011-11-17

    Boeing. All rights reserved. 6 • Provides Corrosion Protection to Steel - No red rust – Corrosion Resistant Coating in Salt Water (Compared to Zinc ...Cd corrosion rate in salt water is lower than zinc • Sacrificially Protects Steel – If Cd coating is scratched Cd coating will corrode first and...prevent steel from corroding • Soft and Ductile – Does Not Reduce the Fatigue Life of High Strength Steel (HSS) – Provides lubricous coating to

  9. The Effect of Scratch- and Lego Mindstorms Ev3-Based Programming Activities on Academic Achievement, Problem-Solving Skills and Logical-Mathematical Thinking Skills of Students

    ERIC Educational Resources Information Center

    Korkmaz, Özgen

    2016-01-01

    The aim of this study was to investigate the effect of the Scratch and Lego Mindstorms Ev3 programming activities on academic achievement with respect to computer programming, and on the problem-solving and logical-mathematical thinking skills of students. This study was a semi-experimental, pretest-posttest study with two experimental groups and…

  10. Bootstrapping Development of a Cloud-Based Spoken Dialog System in the Educational Domain from Scratch Using Crowdsourced Data. Research Report. ETS RR-16-16

    ERIC Educational Resources Information Center

    Ramanarayanan, Vikram; Suendermann-Oeft, David; Lange, Patrick; Ivanov, Alexei V.; Evanini, Keelan; Yu, Zhou; Tsuprun, Eugene; Qian, Yao

    2016-01-01

    We propose a crowdsourcing-based framework to iteratively and rapidly bootstrap a dialog system from scratch for a new domain. We leverage the open-source modular HALEF dialog system to deploy dialog applications. We illustrate the usefulness of this framework using four different prototype dialog items with applications in the educational domain…

  11. Exosome production and its regulation of EGFR during wound healing in renal tubular cells.

    PubMed

    Zhou, Xiangjun; Zhang, Wei; Yao, Qisheng; Zhang, Hao; Dong, Guie; Zhang, Ming; Liu, Yutao; Chen, Jian-Kang; Dong, Zheng

    2017-06-01

    Kidney repair following injury involves the reconstitution of a structurally and functionally intact tubular epithelium. Growth factors and their receptors, such as EGFR, are important in the repair of renal tubules. Exosomes are cell-produced small (~100 nm in diameter) vesicles that contain and transfer proteins, lipids, RNAs, and DNAs between cells. In this study, we examined the relationship between exosome production and EGFR activation and the potential role of exosome in wound healing. EGFR activation occurred shortly after scratch wounding in renal tubular cells. Wound repair after scratching was significantly promoted by EGF and suppressed by EGFR inhibitor gefitinib. Interestingly, scratch wounding induced a significant increase of exosome production. The exosome production was decreased by EGF and increased by gefitinib, suggesting a suppressive role of EGFR signaling in exosome production. Conversely, inhibition of exosome release by GW4869 and manumycin A markedly increased EGFR activation and promoted wound healing. Moreover, exosomes derived from scratch-wounding cells could inhibit wound healing. Collectively, the results indicate that wound healing in renal tubular cells is associated with EGFR activation and exosome production. Although EGFR activation promotes wound healing, released exosomes may antagonize EGFR activation and wound healing. Copyright © 2017 the American Physiological Society.

  12. Evaluation of long-term corrosion durability and self-healing ability of scratched coating systems on carbon steel in a marine environment

    NASA Astrophysics Data System (ADS)

    Zhao, Xia; Chen, Changwei; Xu, Weichen; Zhu, Qingjun; Ge, Chengyue; Hou, Baorong

    2017-09-01

    Defects in protective-coating systems on steel surfaces are inevitable in practical engineering applications. A composite coating system, including a primer, middle coat and topcoat, were used to protect carbon steel from corrosion in a marine environment. Two environmental additives, glass fibers and thiourea, were applied in the middle coat to modify the coating system. The long-term corrosion durability and self-healing ability of the scratched coating system were evaluated by multiple methods. Results of the electrochemical technologies indicated that the coating system that contained 0.5 wt.% fibers and 0.5 wt.% thiourea presented good corrosion protection and self-healing for carbon steel when immersed in 3.5% NaCl for 120 d. Evolution of localized corrosion factors with time, as obtained from the current distribution showed that fibers combined with thiourea could inhibit the occurrence of local corrosion in scratched coating systems and retarded the corrosion development significantly. Surface characterization suggested that adequate thiourea could be absorbed uniformly on fibers for a long time to play an important role in protecting the carbon steel. Finally, schematic models were established to demonstrate the action of fibers and thiourea on the exposed surface of the carbon steel and the scratched coating system in the entire deterioration process.

  13. 3-Bromopyruvate reverses hypoxia-induced pulmonary arterial hypertension through inhibiting glycolysis: In vitro and in vivo studies.

    PubMed

    Chen, Fangzheng; Wang, Heng; Lai, Jiadan; Cai, Shujing; Yuan, Linbo

    2018-05-04

    Pulmonary arterial smooth muscle cell (PASMC) proliferation is vital to pulmonary vascular remodeling in pulmonary arterial hypertension (PAH) pathogenesis, and inhibiting PASMC metabolism could serve as a new possible therapy to reverse the process. 3-Bromopyruvate (3-BrPA) is an effective glycolysis inhibitor with its effect in PAH remains unclear. Our study aims to assess the therapeutic effect of 3-BrPA in PAH rats and investigate the possible mechanism of 3-BrPA in PASMC proliferation and apoptosis. 27 healthy SD rats were grouped and treated with hypoxia/normoxia and administration of 3-BrPA/physiological saline. Mean pulmonary artery pressure (mPAP) and cardiac output (CO) were measured and pulmonary vascular resistance (PVR) was calculated. Right ventricular hypertrophy index (RVHI) was calculated to evaluate the right ventricular hypertrophy degree. The percentage of medial wall area (WA%) and medial wall thickness (WT%) were measured by image analysis. PASMCs groups received hypoxia/normoxia treatments and 3-BrPA/physiological saline. PASMC proliferation and migration were respectively detected by CCK-8 and cell wound scratch assay. Hexokinase II (HK-2) expression and lactate level were respectively measured by Western Blotting and lactate test kit to detect glycolysis. mPAP, PVR, PVHI, WA% and WT% in rats increased after the hypoxia treatment, but were lower compared to rats received 3-BrPA in hypoxia environment. HK-2 expression, lactate concentration, OD value and scratch areas in PASMCs increased after the hypoxia treatment, but were decreased after the administration of 3-BrPA. 3-BrPA can inhibit PASMC proliferation and migration by inhibiting glycolysis, and is effective in reversing the vascular remodeling in hypoxia-induced PAH rats. Copyright © 2017. Published by Elsevier B.V.

  14. Modification of Ti6Al4V implant surfaces by biocompatible TiO2/PCL hybrid layers prepared via sol-gel dip coating: Structural characterization, mechanical and corrosion behavior.

    PubMed

    Catauro, Michelina; Bollino, Flavia; Giovanardi, Roberto; Veronesi, Paolo

    2017-05-01

    Surface modification of metallic implants is a promising strategy to improve tissue tolerance, osseointegration and corrosion resistance of them. In the present work, bioactive and biocompatible organic-inorganic hybrid coatings were prepared using a sol-gel dip coating route. They consist of an inorganic TiO 2 matrix in which different percentages of poly(ε-caprolactone) (PCL), a biodegradable and biocompatible polymer, were incorporated. The coatings were used to modify the surface of Ti6Al4V substrates in order to improve their wear and corrosion resistance. The chemical structure of the coatings was analyzed by attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopy. Coating microstructure, mechanical properties and ability to inhibit the corrosion of the substrates were evaluated as a function of the PCL amount. Scanning electron microscopy (SEM) showed that the polymer allows to obtain crack-free coatings, but when high percentages were added uncoated areas appear. Nano-indentation tests revealed that, as expected, surface hardness and elastic modulus decrease as the percentage of polymeric matrix increases, but scratch testing demonstrated that the coatings are effective in preventing scratching of the underlying metallic substrate, at least for PCL contents up to 20wt%. The electrochemical tests (polarization curves acquired in order to evaluate the corrosion resistance) allowed to asses that the coatings have a significant effect in term of corrosion potential (E corr ) but they do not significantly affect the passivation process that titanium undergoes in contact with the test solution used (modified Dulbecco's phosphate-buffered saline or DPBS). Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Rare successful pregnancy in a patient with Swyer Syndrome.

    PubMed

    Taneja, Jyoti; Ogutu, David; Ah-Moye, Michael

    2016-10-01

    To report a rare successful pregnancy after fertility treatment in a patient with Swyer syndrome. Case report. Herts & Essex Fertility Centre, Cheshunt, UK. A 36-year-old patient with 46, XY gonadal dysgenesis. 31 year old husband with normal sperm analysis. Chromosomal analysis, Saline infusion sonography, Pipelle endometrial scratch, ICSI using donor eggs, Embryo Transfer, and Caesarean delivery. Successful pregnancy and live birth. Successful treatment with donor eggs, pregnancy, and delivery. A patient with 46, XY gonadal dysgenesis in a specially tailored fertility program, can maintain a normal pregnancy and delivery.

  16. Synthesis and performance of Zn-Ni-P thin films

    NASA Astrophysics Data System (ADS)

    Soare, V.; Burada, M.; Constantin, I.; Ghita, M.; Constantin, V.; Miculescu, F.; Popescu, A. M.

    2015-03-01

    The electroplating of Zn-Ni-P thin film alloys from a sulfate bath containing phosphoric and phosphorous acid was investigated. The bath composition and the deposition parameters were optimized through Hull cell experiments, and the optimum experimental conditions were determined (pH = 2, temperature = 298-313 K, zinc sulfate concentration = 30 g·L-1, EDTA concentration = 15 g·L-1, and current density, = ,1.0-2.0 A·dm-2). The SEM analysis of the coating deposited from the optimum bath revealed fine-grained deposits of the alloy in the presence of EDTA. Optical microscopy analysis indicated an electrodeposited thin film with uniform thickness and good adhesion to the steel substrate. The good adherence of the coatings was also demonstrated by the scratch tests that were performed, with a maximum determined value of 25 N for the critical load. Corrosion resistance tests revealed good protection of the steel substrate by the obtained Zn-Ni-P coatings, with values up to 85.89% for samples with Ni contents higher than 76%. The surface analysis of the thin film samples before and after corrosion was performed by X-ray photoelectron spectroscopy (XPS). Project support by the Partnership Romanian Research Program (PNCDI2), CORZIFILM Project nr.72-221/2008-2011 and “EU (ERDF) and Romanian Government” that allowed for acquisition of the research infrastructure under POS-CEEO 2.2.1 project INFRANANOCHEM-Nr.19/01.03.2009.

  17. The Effect of In-Service Training of Computer Science Teachers on Scratch Programming Language Skills Using an Electronic Learning Platform on Programming Skills and the Attitudes towards Teaching Programming

    ERIC Educational Resources Information Center

    Alkaria, Ahmed; Alhassan, Riyadh

    2017-01-01

    This study was conducted to examine the effect of in-service training of computer science teachers in Scratch language using an electronic learning platform on acquiring programming skills and attitudes towards teaching programming. The sample of this study consisted of 40 middle school computer science teachers. They were assigned into two…

  18. MB20B Base Stock as Tarnish Promoter or Preventor.

    DTIC Science & Technology

    1981-04-27

    sites for which a "c" lineshape characterizes the sulfur signal , whereas a small amount of oxygen is generally detected where the other sulfur...contains a small amount of silver (15). Lineshape "a" characterized all sulfur signals originating outside the scratched areas; within the scratches...LINESHAPES (a) (b) (c) Fig. 3 - Comparison of the lineshapes for the low-energy sulfur Auger signals . The designations shown here are used to identify

  19. Interactive augmented reality using Scratch 2.0 to improve physical activities for children with developmental disabilities.

    PubMed

    Lin, Chien-Yu; Chang, Yu-Ming

    2015-02-01

    This study uses a body motion interactive game developed in Scratch 2.0 to enhance the body strength of children with disabilities. Scratch 2.0, using an augmented-reality function on a program platform, creates real world and virtual reality displays at the same time. This study uses a webcam integration that tracks movements and allows participants to interact physically with the project, to enhance the motivation of children with developmental disabilities to perform physical activities. This study follows a single-case research using an ABAB structure, in which A is the baseline and B is the intervention. The experimental period was 2 months. The experimental results demonstrated that the scores for 3 children with developmental disabilities increased considerably during the intervention phrases. The developmental applications of these results are also discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Collective cell migration during inflammatory response

    NASA Astrophysics Data System (ADS)

    Wu, Di; Stroka, Kimberly; Aranda-Espinoza, Helim

    2012-02-01

    Wound scratch healing assays of endothelial cell monolayers is a simple model to study collective cell migration as a function of biological signals. A signal of particular interest is the immune response, which after initial wounding in vivo causes the release of various inflammatory factors such as tumor necrosis alpha (TNF-α). TNF-α is an innate inflammatory cytokine that can induce cell growth, cell necrosis, and change cell morphology. We studied the effects of TNF-α on collective cell migration using the wound healing assays and measured several migration metrics, such as rate of scratch closure, velocities of leading edge and bulk cells, closure index, and velocity correlation functions between migrating cells. We observed that TNF-α alters all migratory metrics as a function of the size of the scratch and TNF-α content. The changes observed in migration correlate with actin reorganization upon TNF-α exposure.

  1. The Ion Channel TRPA1 Is Required for Chronic Itch

    PubMed Central

    Wilson, Sarah R.; Nelson, Aislyn M.; Batia, Lyn; Morita, Takeshi; Estandian, Daniel; Owens, David M.; Lumpkin, Ellen A.; Bautista, Diana M.

    2013-01-01

    Chronic itch is a debilitating condition that affects one in 10 people. Little is known about the molecules that mediate chronic itch in primary sensory neurons and skin. We demonstrate that the ion channel TRPA1 is required for chronic itch. Using a mouse model of chronic itch, we show that scratching evoked by impaired skin barrier is abolished in TRPA1-deficient animals. This model recapitulates many of the pathophysiological hallmarks of chronic itch that are observed in prevalent human diseases such as atopic dermatitis and psoriasis, including robust scratching, extensive epidermal hyperplasia, and dramatic changes in gene expression in sensory neurons and skin. Remarkably, TRPA1 is required for both transduction of chronic itch signals to the CNS and for the dramatic skin changes triggered by dry-skin-evoked itch and scratching. These data suggest that TRPA1 regulates both itch transduction and pathophysiological changes in the skin that promote chronic itch. PMID:23719797

  2. Fabricating Ohmic contact on Nb-doped SrTiO{sub 3} surface in nanoscale

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

    Wang, Yuhang; National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, Chinese Academy of Engineering Physics, Mianyang, Sichuan 621999; Shi, Xiaolan

    2016-05-09

    Fabricating reliable nano-Ohmic contact on wide gap semiconductors is an important yet difficult step in oxide nanoelectronics. We fabricated Ohmic contact on the n-type wide gap oxide Nb-doped SrTiO{sub 3} in nanoscale by mechanically scratching the surface using an atomic force microscopy tip. Although contacted to high work function metal, the scratched area exhibits nearly linear IV behavior with low contact resistance, which maintains for hours in vacuum. In contrast, the unscratched area shows Fowler–Nordheim tunneling dominated Schottky rectifying behavior with high contact resistance. It was found that the Ohmic conductivity in the scratched area was drastically suppressed by oxygenmore » gas indicating the oxygen vacancy origin of the Ohmic behavior. The surface oxygen vacancy induced barrier width reduction was proposed to explain the phenomena. The nanoscale approach is also applicable to macroscopic devices and has potential application in all-oxide devices.« less

  3. Tuning the Mechanical and Antimicrobial Performance of a Cu-Based Metallic Glass Composite through Cooling Rate Control and Annealing

    PubMed Central

    Villapun, Victor Manuel; Esat, Faye; Bull, Steve; Dover, Lynn George; Gonzalez, Sergio

    2017-01-01

    The influence of cooling rate on the wear and antimicrobial performance of a Cu52Z41Al7 (at. %) bulk metallic glass (BMG) composite was studied and the results compared to those of the annealed sample (850 °C for 48 h) and to pure copper. The aim of this basic research is to explore the potential use of the material in preventing the spread of infections. The cooling rate is controlled by changing the mould diameter (2 mm and 3 mm) upon suction casting and controlling the mould temperature (chiller on and off). For the highest cooling rate conditions CuZr is formed but CuZr2 starts to crystallise as the cooling rate decreases, resulting in an increase in the wear resistance and brittleness, as measured by scratch tests. A decrease in the cooling rate also increases the antimicrobial performance, as shown by different methodologies (European, American and Japanese standards). Annealing leads to the formation of new intermetallic phases (Cu10Zr7 and Cu2ZrAl) resulting in maximum scratch hardness and antimicrobial performance. However, the annealed sample corrodes during the antimicrobial tests (within 1 h of contact with broth). The antibacterial activity of copper was proved to be higher than that of any of the other materials tested but it exhibits very poor wear properties. Cu-rich BMG composites with optimised microstructure would be preferable for some applications where the durability requirements are higher than the antimicrobial needs. PMID:28772866

  4. De-Icing Systems of Flight Vehicles. Bases of Design Methods for Testing. Part 1,

    DTIC Science & Technology

    1979-09-07

    conducting filn; 2 - external glass; 3 - ela.tic Iajar; 4 - internal glass. Page 62. Therefore the film can be ueposited on many plastic transparent...specially developed polyester plastic "SayresijA-92011 dud of its varieties which many times are more stable agai.nst bcr~tches, than other transpar~r.t... plastics . Furthermore, aiii uaveoped the methcds of the restcratioji of glasses from solid plastic6 via the polishing of small/fine? scratches or with tho

  5. Comparison of structural and optical properties of TeO2 nanostructures synthesized using various substrate conditions

    NASA Astrophysics Data System (ADS)

    Jung, Taek-Kyun; Ryou, Min; Lee, Ji-Woon; Hyun, Soong-Keun; Na, Han Gil; Jin, Changhyun

    2017-11-01

    Several TeO2 low-dimensional nanostructures were prepared by thermal evaporation using four substrate conditions: (1) a bare substrate, (2) a scratched substrate, (3) a Au-catalyst-assisted substrate, and (4) a multi-walled carbon nanotube (MWCNT)-assisted substrate. Scanning electron microscopy and transmission electron microscopy analysis reveals that the morphologies of the nanostructures synthesized using these methods gradually changed from nanoparticles to ultra-thin nanowires with single tetragonal-type TeO2. Photoluminescence (PL) spectra reveal that the PL intensities of the TeO2 nanomaterials obtained using methods (1) and (2) are slightly increased, whereas the intensities of the TeO2 nanostructures obtained using methods (3) and (4) differ significantly depending on the initial substrate conditions. The emission peak is also blue-shifted from 440 nm to 430 nm for the scratched surface condition due to an excitonic transition. The increase in the blue emission for the MWCNT-assisted condition is attributed to the degree and type of excitons and defects in the TeO2 nanostructures.

  6. Postnatal ontogeny of limb proportions and functional indices in the subterranean rodent Ctenomys talarum (Rodentia: Ctenomyidae).

    PubMed

    Echeverría, Alejandra Isabel; Becerra, Federico; Vassallo, Aldo Iván

    2014-08-01

    Burrow construction in the subterranean Ctenomys talarum (Rodentia: Ctenomyidae) primarily occurs by scratch-digging. In this study, we compared the limbs of an ontogenetic series of C. talarum to identify variation in bony elements related to fossorial habits using a morphometrical and biomechanical approach. Diameters and functional lengths of long bones were measured and 10 functional indices were constructed. We found that limb proportions of C. talarum undergo significant changes throughout postnatal ontogeny, and no significant differences between sexes were observed. Five of six forelimb indices and two of four hindlimb indices showed differences between ages. According to discriminant analysis, the indices that contributed most to discrimination among age groups were robustness of the humerus and ulna, relative epicondylar width, crural and brachial indices, and index of fossorial ability (IFA). Particularly, pups could be differentiated from juveniles and adults by more robust humeri and ulnae, wider epicondyles, longer middle limb elements, and a proportionally shorter olecranon. Greater robustness indicated a possible compensation for lower bone stiffness while wider epicondyles may be associated to improved effective forces in those muscles that originate onto them, compensating the lower muscular development. The gradual increase in the IFA suggested a gradual enhancement in the scratch-digging performance due to an improvement in the mechanical advantage of forearm extensors. Middle limb indices were higher in pups than in juveniles-adults, reflecting relatively more gracile limbs in their middle segments, which is in accordance with their incipient fossorial ability. In sum, our results show that in C. talarum some scratch-digging adaptations are already present during early postnatal ontogeny, which suggests that they are prenatally shaped, and other traits develop progressively. The role of early digging behavior as a factor influencing on morphology development is discussed. © 2014 Wiley Periodicals, Inc.

  7. Unraveling mysteries associated with cat-scratch disease, bacillary angiomatosis, and related syndromes.

    PubMed Central

    Regnery, R.; Tappero, J.

    1995-01-01

    The search for the infectious agents responsible for cat-scratch disease, bacillary angiomatosis, and related syndromes has a long and often circuitous history. Recognition of the etiologic agents and a new understanding of the fundamental features of the epidemiology and natural history of modern day Bartonella (formerly Rochalimaea)-associated diseases culminate a multipartite story that combines clinical medicine, traditional microbiology, and novel technological approaches to solve a long-standing enigma. PMID:8903149

  8. Highly Transparent, Nanofiller-Reinforced Scratch-Resistant Polymeric Composite Films Capable of Healing Scratches.

    PubMed

    Li, Yang; Chen, Shanshan; Li, Xiang; Wu, Mengchun; Sun, Junqi

    2015-10-27

    Integration of healability and mechanical robustness is challenging in the fabrication of highly transparent films for applications as protectors in optical and displaying devices. Here we report the fabrication of healable, highly transparent and scratch-resistant polymeric composite films that can conveniently and repeatedly heal severe damage such as cuts of several tens of micrometers wide and deep. The film fabrication process involves layer-by-layer (LbL) assembly of a poly(acrylic acid) (PAA) blend and branched poly(ethylenimine) (bPEI) blend, where each blend contains the same polyelectrolytes of low and high molecular weights, followed by annealing the resulting PAA/bPEI films with aqueous salt solution and incorporation of CaCO3 nanoparticles as nanofillers. The rearrangement of low-molecular-weight PAA and bPEI under aqueous salt annealing plays a critical role in eliminating film defects to produce optically highly transparent polyelectrolyte films. The in situ formation of tiny and well-dispersed CaCO3 nanoparticles gives the resulting composite films enhanced scratch-resistance and also retains the healing ability of the PAA/bPEI matrix films. The reversibility of noncovalent interactions among the PAA, bPEI, and CaCO3 nanoparticles and the facilitated migration of PAA and bPEI triggered by water enable healing of the structural damage and restoration of optical transparency of the PAA/bPEI films reinforced with CaCO3 nanoparticles.

  9. Task Analysis - Aircraft Structural Maintenance AFSC 458X2

    DTIC Science & Technology

    1989-08-01

    GAGES OR METERS 13 10 23 SELECT WEIGHT MEASURING SCALES 15 6 21 RECALL TYPES, PROPERTIES, AND CHARACTERISTICS 8 11 19 OF PLASTICS SELECT COMMON...SURFACES (K0494) 121 00480 SHOT PEEN METAL SURFACES (K0498) 123 00490 BALANCE AIRCRAFT CONTROL SURFACES 125 00500 CLEAN PLASTICS (0275) 127 00510...STORE TRANSPARENT PLASTICS IN PROPER ENVIRONMENT (J0299) 128 00520 POLISH OUT SURFACE SCRATCHES 129 00530 CUT PLASTICS 131 00540 RESEARCH AIRCRAFT

  10. The reflectivity, wettability and scratch durability of microsurface features molded in the injection molding process using a dynamic tool tempering system

    NASA Astrophysics Data System (ADS)

    Kuhn, Sascha; Burr, August; Kübler, Michael; Deckert, Matthias; Bleesen, Christoph

    2011-02-01

    In this paper the replication qualities of periodically and randomly arranged micro-features molded in the injection molding process and their effects on surface properties are studied. The features are molded in PC, PMMA and PP at different mold wall temperatures in order to point out the necessity and profitability of a variotherm mold wall temperature control system. A one-dimensional heat conduction model is proposed to predict the cycle times of the variotherm injection molding processes. With regard to these processes, the molding results are compared to the molded surface feature heights using an atomic force microscope. In addition, the effects of the molded surface features on macroscopic surfaces are characterized in terms of light reflection using a spectrometer and in terms of water wettability by measuring the static contact angle. Furthermore, due to the sensitivity of the surface features on the molded parts, their durability is compared in a scratch test with a diamond tip. This leads to successful implementation in applications in which the optical appearance, in terms of gloss and reflection, and the water repellence, in terms of drag flow and adhesion, are of importance.

  11. Australian bat lyssavirus: a recently discovered new rhabdovirus.

    PubMed

    Warrilow, D

    2005-01-01

    Australian bat lyssavirus (ABLV), first identified in 1996, has been associated with two human fatalities. ABLV is genetically and serologically distinct from, but is closely related to, classical rabies. It has a bullet-shaped morphology by electron microscopy. There are two strains of ABLV known: one circulates in frugivorous bats, sub-order Megachiroptera, and the other circulates in the smaller, mainly insectivorous bats, sub-order Microchiroptera. Each strain has been associated with one human fatality. Surveillance indicates infected bats are widespread at a low frequency on the Australian mainland. It is unclear how long ABLV has been present in Australia, although molecular clock studies suggest the two strains separated 950 or 1,700 years ago based on synonymous or non-synonymous nucleotide changes, respectively. Recent serological surveys suggest a closely related virus may exist in the Philippines. Due to demonstrated cross-protection in mice, rabies vaccine is used to prevent infection. Rabies post-exposure prophylaxis (PEP) protocols have been adopted for when a human is scratched or bitten by a suspect bat. A long-term commitment to public health programs that test bats that have been involved in scratch or bite incidents, followed by PEP if appropriate, will be necessary to minimise further human infection.

  12. Structure and Mechanical Properties of Polybutadiene Thin Films Bound to Surface-Modified Carbon Interface.

    PubMed

    Hori, Koichiro; Yamada, Norifumi L; Fujii, Yoshihisa; Masui, Tomomi; Kishimoto, Hiroyuki; Seto, Hideki

    2017-09-12

    The structure and mechanical properties of polybutadiene (PB) films on bare and surface-modified carbon films were examined. There was an interfacial layer of PB near the carbon layer whose density was higher (lower) than that of the bulk material on the hydrophobic (hydrophilic) carbon surface. To glean information about the structure and mechanical properties of PB at the carbon interface, a residual layer (RL) adhering to the carbon surface, which was considered to be a model of "bound rubber layer", was obtained by rinsing the PB film with toluene. The density and thickness of the RLs were identical to those of the interfacial layer of the PB film. In accordance with the change in the density, normal stress of the RLs evaluated by atomic force microscopy was also dependent on the surface free energy: the RLs on the hydrophobic carbon were hard like glass, whereas those on the hydrophilic carbon were soft like rubber. Similarly, the wear test revealed that the RLs on the hydrophilic carbon could be peeled off by scratching under a certain stress, whereas the RLs on the hydrophobic carbons were resistant to scratching.

  13. 3-ω damage threshold evaluation of final optics components using Beamlet Mule and off-line testing

    NASA Astrophysics Data System (ADS)

    Kozlowski, Mark R.; Maricle, Stephen M.; Mouser, Ron P.; Schwartz, Sheldon; Wegner, Paul J.; Weiland, Timothy L.

    1999-07-01

    A statistics-based model is being develop to predict the laser-damage-limited lifetime of UV optical components on the NIF laser. In order to provide data for the mode, laser damage experiments were performed on the Beamlet laser system at LLNL. An early protoype NIF focus lens was exposed to twenty 351 nm pulses at an average fluence of 5 J/cm2, 3ns. Using a high resolution optic inspection inspection system a total of 353 damage sites was detected within the 1160 cm2 beam aperture. Through inspections of the lens before, after and, in some cases, during the campaign, pulse to pulse damage growth rates were measured for damage initiating both on the surface and at bulk inclusions. Growth rates as high as 79 micrometers /pulse were observed for damage initiating at pre-existing scratches in the surface. For most damage sites on the optic, both on the surface and at bulk inclusions. Growth rates as high as 79 micrometers /pulse were observed for damage initiating at per- existing scratches in the surface. For most damage sites on the optic, both surface and bulk, the damage growth rate was approximately 10(Mu) m/pulse.

  14. [Comparison of surface roughness of nanofilled and microhybrid composite resins after curing and polishing].

    PubMed

    Jiang, Hong; Lv, Da; Liu, Kailei; Zhang, Weisheng; Yao, Yao; Liao, Chuhong

    2014-05-01

    To compare the surface roughness of nanofilled dental composite resin and microhybrid composite resins after curing and polishing. A nanofilled composite (Z350) and 4 microhybrid composites (P60, Z250, Spectrum, and AP-X) were fabricated from the lateral to the medial layers to prepare 8 mm×8 mm×5 mm cubical specimens. The 4 lateral surfaces of each specimens were polished with abrasive disks (Super-Snap). Profilometer was used to test the mean surface roughness (Ra) after polishing. P60 had the lowest Ra (0.125∓0.030 µm) followed by Z250 and Spectrum. The Ra of Z350 (0.205∓0.052 µm) was greater than that of the other 3 resins, and AP-X had the roughest surfaces. Under scanning electron microscope, the polished faces of P60 resin were characterized by minor, evenly distributed particles with fewer scratches; the polished faces of Z350 presented with scratches where defects of the filling material could be seen. The nanofilled composite Z350 has smooth surface after polishing by abrasive disks, but its smoothness remains inferior to that of other micro-hybrid composite resins.

  15. Algorithm for Automatic Behavior Quantification of Laboratory Mice Using High-Frame-Rate Videos

    NASA Astrophysics Data System (ADS)

    Nie, Yuman; Takaki, Takeshi; Ishii, Idaku; Matsuda, Hiroshi

    In this paper, we propose an algorithm for automatic behavior quantification in laboratory mice to quantify several model behaviors. The algorithm can detect repetitive motions of the fore- or hind-limbs at several or dozens of hertz, which are too rapid for the naked eye, from high-frame-rate video images. Multiple repetitive motions can always be identified from periodic frame-differential image features in four segmented regions — the head, left side, right side, and tail. Even when a mouse changes its posture and orientation relative to the camera, these features can still be extracted from the shift- and orientation-invariant shape of the mouse silhouette by using the polar coordinate system and adjusting the angle coordinate according to the head and tail positions. The effectiveness of the algorithm is evaluated by analyzing long-term 240-fps videos of four laboratory mice for six typical model behaviors: moving, rearing, immobility, head grooming, left-side scratching, and right-side scratching. The time durations for the model behaviors determined by the algorithm have detection/correction ratios greater than 80% for all the model behaviors. This shows good quantification results for actual animal testing.

  16. Spice allergy in celery-sensitive patients.

    PubMed

    Stäger, J; Wüthrich, B; Johansson, S G

    1991-08-01

    Scratch tests (SCT) with powdered commercial spices were performed in 70 patients with positive skin tests to birch and/or mugwort pollens and celery. Positive SCT to aniseed, fennel, coriander and cumin--all from the same botanical family (Apiaceae) as celery--were observed in more than 24 patients. Spices from unrelated families (red pepper, white pepper, ginger, nutmeg, cinnamon) elicited positive immediate skin test reactions only in three of 11 patients. Specific serum IgE to spices (determined in 41 patients with positive RAST to celery) up to class 3 were seen especially in patients with celery-mugwort or celery-birch-mugwort association, and concerned various botanical families. Celery-birch association pattern was linked to positive reactions (RAST classes 1-2) to spices from the Apiaceae family only.

  17. Preliminary measurements on heat balance in pneumatic tires

    NASA Technical Reports Server (NTRS)

    Nybakken, G. H.; Collart, D. Y.; Staples, R. J.; Lackey, J. I.; Clark, S. K.; Dodge, R. N.

    1973-01-01

    A variety of tests was undertaken to determine the nature of heat generation associated with a pneumatic tire operating under various conditions. Tests were conducted to determine the magnitude and distribution of internally generated heat caused by hysteresis in the rubber and ply fabric in an automobile tire operating under conditions of load, pressure, and velocity representative of normal operating conditions. These included tests at various yaw angles and tests with braking applied. In other tests, temperature sensors were mounted on a road to measure the effect of a tire rolling over and an attempt was made to deduce the magnitude and nature of interfacial friction from the resulting information. In addition, tests were performed using the scratch plate technique to determine the nature of the motion between the tire and road. Finally, a model tire was tested on a roadwheel, the surface covering which could be changed, and an optical pyrometer was used to measure rubber surface temperatures.

  18. Scratching experiments on quartz crystals: Orientation effects in chipping

    NASA Astrophysics Data System (ADS)

    Tellier, C. R.; Benmessaouda, D.

    1994-06-01

    The deformation and microfracture properties of quartz crystals were studied by scratching experiments. The critical load at which microfractures are initiated was found to be orientation dependent, whereas the average width of ductile grooves and chips remained relatively insensitive to crystal orientation. In contrast, a marked anisotropy in the shape of chips was observed. This anisotropy has been interpreted in terms of microfractures propagating preferentially along slip planes. Simple geometrical conditions for the SEM (scanning electron microscopy) observation of active slip planes are proposed.

  19. Polyfibroblast: A Self-Healing and Galvanic Protection Additive

    DTIC Science & Technology

    2013-09-25

    Specifically we looked at emulsifier (Gum Arabic vs. SiC^), polymer-forming monomer (IPDI vs. BCI ), silane molecular weight (C12 vs. C18 vs. C8-C18...le+6J tu ie+4- le+2 U le+0 ■ Coating ■ Scratch BCI IPDI Isocyanate Type ICoating |Scratch Figure 3: A) Corrosion resistance of the...surprising. The type of monomer also did not appear to matter in these measurements. Whether polymerized from IPDI or BCI , the extent of self-healing

  20. Wound healing potential of a dimeric InlB variant analyzed by in vitro experiments on re-epithelialization of human skin models.

    PubMed

    Kolditz, F; Krausze, J; Heinz, D W; Niemann, H H; Müller-Goymann, C C

    2014-02-01

    A constitutively dimeric truncated variant of internalin B (InlB321-CD), acting as stimulator of the receptor tyrosine kinase MET, was tested for dermal wound-healing potential. Due to a lack of the endogenous MET agonist HGF/SF in chronic wounds, HGF/SF substitution by an InlB321-CD-loaded hydrogel might be beneficial in chronic wound therapy. In this study, InlB321-CD in solution and incorporated in a hydrogel was tested for mitogenic effects on immortalized human dermal keratinocytes (HaCaT) with an MTT assay. Cell migration was investigated with a scratch assay on primary keratinocytes (PHK) and on HaCaT. For the latter, scratching needed to be mitomycin C-controlled. InlB321-CD effects on a model of human skin were analyzed histologically with respect to viability. InlB321-CD led to dose-dependent proliferative effects on HaCaT cells whereas the equimolar dose of monomeric InlB321 did not. Upon hydrogel incorporation of InlB321-CD its mitogenic activity for HaCaT cells was maintained thus confirming the hydrogel as a promising drug delivery system. Motogenic effects were shown on both HaCaT and PHK cells. InlB321-CD neither possesses cytotoxic effects on the viability of a human skin model nor alters its organotypic cell morphology. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Biological and nano-indentation properties of polybenzoxazine-based composites reinforced with zirconia particles as a novel biomaterial.

    PubMed

    Lotfi, L; Javadpour, J; Naimi-Jamal, M R

    2018-01-01

    The biological and mechanical properties of substances are relevant to their application as biomaterials and there are many efforts to enhance biocompatibility and mechanical properties of bio-medical materials. In this study, to achieve a low rate of shrinkage during polymerization, good mechanical properties, and excellent biocompatibility, benzoxazine based composites were synthesized. Benzoxazine monomer was synthesized using a solventless method. FTIR and DSC analysis were carried out to determine the appropriate polymerization temperature. The low viscosity of the benzoxazine monomer at 70°C attract us to use in situ polymerization after high speed ball milling of the benzoxazine and it mixture with different weight fractions of zirconia particles. Dispersion and adhesion between the ceramic and polymer components were evaluate by SEM. To evaluate the biological properties and toxicity of the polybenzoxazine-based composite samples reinforced with zirconia particles, 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay was conducted. The micromechanical properties of each composite were evaluated by more than 20 nanoindentation tests and 3 nanoscratching tests. Surface topography of scratched regions was investigated using Atomic Force Microscopy. Shrinkage was simulated by Materials Studio software. SEM images showed good dispersion and adhesion between the ceramic and polymer components. Biocompatibility assay showed excellent in vitro biocompatibility. Nano-indentation force-displacement curves showed matrix, reinforcement and interphase regions in specimens and excellent homogeneity in mechanical properties. The nanoindentation results showed that the addition of zirconia particles to the polybenzoxazine matrix increased the modulus and hardness of the neat polybenzoxazine; however, by adding more than an optimum level of reinforcement particles, the mechanical properties decreased due to the agglomeration of reinforcement particles and weak interphase that cause inappropriate load transferring between matrix and reinforcement particles. Results of nano-scratching tests showed effects of zirconia particles as reinforcement on the coeffiecient of friction of the synthesized composites. Shrinkage simulation showed a low rate of shrinkage for polybenzoxazine in comparison with other low shrinkage polymers, such as Bis-GMA. Polybenzoxazine based composites that reinforced with an optimum amount of zirconia particles (60% wt micro and 10% wt nano-particles) could be used as a novel biomaterial duo to its excellent biocompatibility, good mechanical properties, appropriate viscosity and low rate of polymeization shrinkage.

  2. Can schools save kids' palates? Cooking from scratch in schools--the greatest food service challenge of our time.

    PubMed

    Collins, Beth

    2012-08-01

    School District Food Service Departments are faced with the enormous task of feeding children in the United States up to two thirds of the meals that they consume during the week at school. The shift in food production since the 1970s produced a trend away from scratch-cooked foods and resulted in more meals created from processed foods. The United States has reached a tipping point where the health of the current generation is compromised by increasing health risks of diet-related disease. Schools have been identified as a critical environment in which there is an opportunity to effect change in what children eat. As a result, in the last 10 years, there has been a resurgence of interest in freshly prepared meals in schools. This article explores one chef’s transition from the private sector to the public sector and the experiences of working with school districts to successfully transform their school food service operations into a scratch cooking model.

  3. Designing for deeper learning in a blended computer science course for middle school students

    NASA Astrophysics Data System (ADS)

    Grover, Shuchi; Pea, Roy; Cooper, Stephen

    2015-04-01

    The focus of this research was to create and test an introductory computer science course for middle school. Titled "Foundations for Advancing Computational Thinking" (FACT), the course aims to prepare and motivate middle school learners for future engagement with algorithmic problem solving. FACT was also piloted as a seven-week course on Stanford's OpenEdX MOOC platform for blended in-class learning. Unique aspects of FACT include balanced pedagogical designs that address the cognitive, interpersonal, and intrapersonal aspects of "deeper learning"; a focus on pedagogical strategies for mediating and assessing for transfer from block-based to text-based programming; curricular materials for remedying misperceptions of computing; and "systems of assessments" (including formative and summative quizzes and tests, directed as well as open-ended programming assignments, and a transfer test) to get a comprehensive picture of students' deeper computational learning. Empirical investigations, accomplished over two iterations of a design-based research effort with students (aged 11-14 years) in a public school, sought to examine student understanding of algorithmic constructs, and how well students transferred this learning from Scratch to text-based languages. Changes in student perceptions of computing as a discipline were measured. Results and mixed-method analyses revealed that students in both studies (1) achieved substantial learning gains in algorithmic thinking skills, (2) were able to transfer their learning from Scratch to a text-based programming context, and (3) achieved significant growth toward a more mature understanding of computing as a discipline. Factor analyses of prior computing experience, multivariate regression analyses, and qualitative analyses of student projects and artifact-based interviews were conducted to better understand the factors affecting learning outcomes. Prior computing experiences (as measured by a pretest) and math ability were found to be strong predictors of learning outcomes.

  4. Skin tests of pollen grains of taxodiaceae and cupressaceae in children with bronchial asthma.

    PubMed

    Midoro-Horiuti, T; Nouno, S; Seino, Y

    1992-10-01

    Atmospheric cedar pollen in the southern region of Okayama Prefecture (situated in south-western Japan) has been counted since 1988. Pollen of different species of the Taxodiaceae family (Cryptomeria japonica, Sequoia sempervirens and Metasequoia glyptostroboides) and Japanese juniper (Juniperus rigida) in the Cupressaceae family, which are propagated mainly in the southern region of Okayama Prefecture, were found among the atmospheric pollen. Scratch tests using the pollen extract from Taxodiaceae and Cupressaceae were performed on children with bronchial asthma. Forty (25%) and 30 (18.8%) of the 160 patients reacted positively to an allergen extract from the pollen grains of Japanese cedar (Cryptomeria japonica) and Japanese juniper, respectively.

  5. Relationships between functional fitness and cognitive impairment in Chinese community-dwelling older adults: a cross-sectional study.

    PubMed

    Yang, Mei; Guo, Yan; Gong, Jie; Deng, Mengyao; Yang, Niannian; Yan, Yaqiong

    2018-05-20

    The aim of this study was to investigate the associations between each functional fitness (FF) domain and cognitive impairment (CI) in Chinese community-dwelling older adults. A community-based, cross-sectional study was conducted. Participants were selected by multistage stratified random sampling in Wuhan City, Hubei Province, Central China, during December 2015-May 2016. A total of 2096 (1031 male and 1065 female) adults older than 65 years were included in our study. Exclusion criteria were age <65 years, losing self-living ability, previously diagnosed with dementia by a neurological physician, severe physical pain, congestive heart failure, dizziness and uncontrolled hypertension (exceeding 160/100 mm Hg). The Senior Fitness Test and the Mini-Mental State Examination were used to measure FF (including 30 s chair stand, 30 s arm curl, 2 min step, 8 foot up-and-go, chair sit-and-reach and back scratch) and screen CI, respectively. Activities of daily living and instrumental activities of daily living questionnaires were administered to evaluate functional status (FS). 32.16% were classified as the CI group. The results showed that the CI group had significantly lower frequency of 30 s chair stand, 30 s arm curl and 2 min step, and longer time to complete the 8 foot up-and-go, shorter chair sit-and-reach and back scratch distance than the non-CI adults (p<0.05). Except for back scratch, older adults with moderate and high levels of FF were less likely to have CI than those with low levels, adjusted by sociodemographics, chronic disease, health condition, health behaviour and FS (p<0.05). The relationship between FF and CI was independent of FS decline in Chinese community-dwelling older people. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  6. The spinal inhibition of N-type voltage-gated calcium channels selectively prevents scratching behavior in mice.

    PubMed

    Maciel, I S; Azevedo, V M; Pereira, T C; Bogo, M R; Souza, A H; Gomez, M V; Campos, M M

    2014-09-26

    The present study investigated the effects of pharmacological spinal inhibition of voltage-gated calcium channels (VGCC) in mouse pruritus. The epidural administration of P/Q-type MVIIC or PhTx3.3, L-type verapamil, T-type NNC 55-0396 or R-type SNX-482 VGCC blockers failed to alter the scratching behavior caused by the proteinase-activated receptor 2 (PAR-2) activator trypsin, injected into the mouse nape skin. Otherwise, trypsin-elicited pruritus was markedly reduced by the spinal administration of preferential N-type VGCC inhibitors MVIIA and Phα1β. Time-course experiments revealed that Conus magus-derived toxin MVIIA displayed significant effects when dosed from 1h to 4h before trypsin, while the anti-pruritic effects of Phα1β from Phoneutria nigriventer remained significant for up to 12h. In addition to reducing trypsin-evoked itching, MVIIA or Phα1β also prevented the itching elicited by intradermal (i.d.) injection of SLIGRL-NH2, compound 48/80 or chloroquine, although they did not affect H2O2-induced scratching behavior. Furthermore, the co-administration of MVIIA or Phα1β markedly inhibited the pruritus caused by the spinal injection of gastrin-releasing peptide (GRP), but not morphine. Notably, the epidural administration of MVIIA or Phα1β greatly prevented the chronic pruritus allied to dry skin model. However, either tested toxin failed to alter the edema formation or neutrophil influx caused by trypsin, whereas they significantly reduced the c-Fos activation in laminas I, II and III of the spinal cord. Our data bring novel evidence on itching transmission mechanisms, pointing out the therapeutic relevance of N-type VGCC inhibitors to control refractory pruritus. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

  7. Preliminary Investigation of Surface Treatments to Enhance the Wear Resistance of 60-Nitinol

    NASA Technical Reports Server (NTRS)

    Stanford, Malcolm K.

    2016-01-01

    The use of protective surface treatments on 60-Nitinol (60wt%Ni-40wt%Ti) was studied. Various nitriding techniques as well as a (Ti, Al)N coating were evaluated visually, microscopically, and by hardness and scratch testing. The chemical composition of the surface treatments was investigated by x-ray techniques. The results indicate that very hard (greater than 1,000 HK) and adherent surface layers can be produced on 60-Nitinol. Further work is needed to determine the tribological properties of these surface treatments in relevant operating environments.

  8. NSI-1 Squib adapter development and final test report for usage on space shuttle gas sampler valve/bottle assembly 3270

    NASA Technical Reports Server (NTRS)

    Siebel, J. E.

    1983-01-01

    The possibility of utilizing the NSI-1 squib in place cartridge assembly 2270 for the function of both events required for the Space Shuttle Gas Sampler Valve/Bottle Assembly 3270 was determined. Additionally, it was a requirement that the closure disk of the NSI-1 squib and explosive residue therefrom be retained from the valve cavity in so far as possible to prevent any significant particulate from scratching the valve bore and causing sample leakage following the postfire 2 event.

  9. Finite element analysis and simulation of rheological properties of bulk molding compound (BMC)

    NASA Astrophysics Data System (ADS)

    Ergin, M. Fatih; Aydin, Ismail

    2013-12-01

    Bulk molding compound (BMC) is one of the important composite materials with various engineering applications. BMC is a thermoset plastic resin blend of various inert fillers, fiber reinforcements, catalysts, stabilizers and pigments that form a viscous, molding compound. Depending on the end-use application, bulk molding compounds are formulated to achieve close dimensional control, flame and scratch resistance, electrical insulation, corrosion and stain resistance, superior mechanical properties, low shrink and color stability. Its excellent flow characteristics, dielectric properties, and flame resistance make this thermoset material well-suited to a wide variety of applications requiring precision in detail and dimensions as well as high performance. When a BMC is used for these purposes, the rheological behavior and properties of the BMC is the main concern. In this paper, finite element analysis of rheological properties of bulk molding composite material was studied. For this purpose, standard samples of composite material were obtained by means of uniaxial hot pressing. 3 point flexural tests were then carried out by using a universal testing machine. Finite element analyses were then performed with defined material properties within a specific constitutive material behavior. Experimental and numerical results were then compared. Good correlation between the numerical simulation and the experimental results was obtained. It was expected with this study that effects of various process parameters and boundary conditions on the rheological behavior of bulk molding compounds could be determined by means of numerical analysis without detailed experimental work.

  10. Interfacial characteristics and determination of cohesive and adhesive strength of plasma-coated hydroxyapatite via nanoindentation and microscratch techniques.

    PubMed

    McManamon, Colm; de Silva, Johann P; Power, John; Ramirez-Garcia, Sonia; Morris, Michael A; Cross, Graham L W

    2014-09-30

    We investigate the chemical composition and mechanical properties of plasma-deposited hydroxyapatite on grit-blasted Ti-6Al-4V coupons as models of typical prosthetic hip implants. Nanoindentation is used to extract the mechanical properties of the hydroxyapatite (HA) coating and to evaluate the behavior of the material as a function of distance from the interface. A microscratch technique was used to determine parameters of cohesive and adhesive failure of the material that are critical in determining the functionality of these biomedical devices. This delamination method has not been studied in detail before and is usually considered to be unsuitable because of the thickness of the HA and the roughness of the substrate. However, through cross-section analysis of the scratch test, we can determine the point at which the HA delaminates from the substrate. It was concluded that spallation occurs locally, and there is no evidence of gross spallation, indicating that the coating is well adhered to the substrate.

  11. Surface mechanical behaviour of composite Ni-P-fly ash/zincate coated aluminium alloy

    NASA Astrophysics Data System (ADS)

    Panagopoulos, C. N.; Georgiou, E. P.

    2009-04-01

    Ni-P-fly ash coatings were produced on zincate coated 5083 wrought aluminium alloy substrates with the aid of an electroless deposition technique. Structural and chemical characterization of the produced coatings was performed with the aid of X-ray diffraction (XRD), scanning electron microscopy (SEM) and electron dispersive X-ray analysis (EDS) techniques. The Ni-P-fly ash coating was found to consist of an amorphous Ni-P matrix with dispersed fly ash particles. The wear resistance of the Ni-P-fly ash coating on zincate treated aluminium alloy was observed to be higher than that of the bare aluminium alloy, when sliding against a stainless steel counterface. In addition, the adhesion between the Ni-P-fly ash/zincate coating and the aluminium alloy substrate was also studied with a scratch testing apparatus. The adhesion strength of Ni-P-fly ash/zincate coating on the aluminium alloy substrate was observed to be higher in comparison to the Ni-P/zincate coating on the same aluminium alloy.

  12. SerpinE2, a poor biomarker of endometrial cancer, promotes the proliferation and mobility of EC cells.

    PubMed

    Shen, Yuan; Wang, Xiaoyu; Xu, Jianping; Lu, Lin

    2017-07-04

    The SerpinE2 pathway is evolutionarily conserved and plays an important role in tumorigenesis. SerpinE2 (a small ubiquitin-related modifier), like ubiquitin, conjugates SerpinE2 proteins onto lysine residues of target proteins. SerpinE2 over-expression has been found in several tumors. Here, we detected the level of SerpinE2 in 72 samples of EC tissue using immunohistochemistry to assess the role of SerpinE2 in EC prognosis. Meanwhile, we knocked down SerpinE2 by siRNA in the HTB-111 and Ishikawa EC cell lines and analyzed the viability and mobility change using an MTT assay, an annexin V/PI apoptosis assay, a wound scratch test and a transwell assay. A Kaplan-Meier analysis indicated a negative correlation between the level of SerpinE2 and the EC prognosis. Silencing SerpinE2 induced cell apoptosis and reduced the migration ability. Our data suggest SerpinE2 works as an oncogene in EC.

  13. Portable Handheld Optical Window Inspection Device

    NASA Technical Reports Server (NTRS)

    Ihlefeld, Curtis; Dokos, Adam; Burns, Bradley

    2010-01-01

    The Portable Handheld Optical Window Inspection Device (PHOWID) is a measurement system for imaging small defects (scratches, pits, micrometeor impacts, and the like) in the field. Designed primarily for window inspection, PHOWID attaches to a smooth surface with suction cups, and raster scans a small area with an optical pen in order to provide a three-dimensional image of the defect. PHOWID consists of a graphical user interface, motor control subsystem, scanning head, and interface electronics, as well as an integrated camera and user display that allows a user to locate minute defects before scanning. Noise levels are on the order of 60 in. (1.5 m). PHOWID allows field measurement of defects that are usually done in the lab. It is small, light, and attaches directly to the test article in any orientation up to vertical. An operator can scan a defect and get useful engineering data in a matter of minutes. There is no need to make a mold impression for later lab analysis.

  14. RF sputtered silicon and hafnium nitrides as applied to 440C steel

    NASA Technical Reports Server (NTRS)

    Grill, A.; Aron, P. R.

    1984-01-01

    Silicon nitride and hafnium nitride coatings were deposited on oxidized and unoxidized 440C stainless steel substrates. Sputtering was done in mixtures of argon and nitrogen gases from pressed powder silicon nitride and from hafnium metal targets. The coatings and the interface between the coating and substrate were investigated by X-ray diffractometry, scanning electron microscopy, energy dispersive X-ray analysis and Auger electron spectroscopy. Oxide was found at all interfaces with an interface width of at least 600 A for the oxidized substrates and at least 300 A for the unoxidized substrates. Scratch test results demonstrate that the adhesion of hafnium nitride to both oxidized and unoxidized 440C is superior to that of silicon nitride. Oxidized 440C is found to have increased adhesion, to both nitrides, over that of unoxidized 440C. Coatings of both nitrides deposited at 8 mtorr were found to have increased adhesion to both oxidized and unoxidized 440C over those deposited at 20 mtorr.

  15. The effect of endometrial scratch on natural-cycle cryopreserved embryo transfer outcomes: a randomized controlled study.

    PubMed

    Mak, Jennifer Sze Man; Chung, Cathy Hoi Sze; Chung, Jacqueline Pui Wah; Kong, Grace Wing Shan; Saravelos, Sotirios H; Cheung, Lai Ping; Li, Tin-Chiu

    2017-07-01

    The benefit of endometrial scratch (ES) prior to embryo transfer is controversial. Systemic analysis has confirmed its potential benefit, especially in women with repeated IVF failures, yet most studies have focused on fresh embryo transfer, and its effect on vitrified-warmed embryo transfer (FET) cycles is yet to be explored. We hereby present our prospective, double-blind, randomized controlled study on the evaluation of the implantation and pregnancy rate after ES prior to natural-cycle FET. A total of 299 patients underwent natural-cycle FET and were randomized to receive ES (n = 115) or endocervical manipulation as control (n = 114) prior to FET cycle, and a total of 196 patients had embryo transfer (93 patients in each group). Our study showed no significant difference in the implantation and pregnancy rate, as well as the clinical and ongoing pregnancy or live birth rates between the two groups. It appears that ES does not have any beneficial effect on an unselected group of women undergoing FET in natural cycles. Further studies on its effect in women with recurrent implantation failure after IVF are warranted. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  16. Masticatory jaw movement of Exaeretodon argentinus (Therapsida: Cynodontia) inferred from its dental microwear

    PubMed Central

    Yamada, Eisuke; Kubo, Mugino O.

    2017-01-01

    Dental microwear of four postcanine teeth of Exaeretodon argentinus was analyzed using both two dimensional (2D) and three dimensional (3D) methods to infer their masticatory jaw movements. Results of both methods were congruent, showing that linear microwear features (scratches) were well aligned and mostly directed to the antero-posterior direction in all four teeth examined. These findings support the palinal masticatory jaw movement, which was inferred in previous studies based on the observation of gross morphology of wear facets. In contrast, the lack of detection of lateral scratches confirmed the absence of the lateral jaw movement that was also proposed by a previous study. Considering previous microwear studies on cynodonts, palinal jaw movements observed in Exaeretodon evolved within cynognathian cynodonts from the fully orthal jaw movement of its basal member. Although there are currently only three studies of dental microwear of non-mammalian cynodonts including the present study, microwear analysis is a useful tool for the reconstruction of masticatory jaw movement and its future application to various cynodonts will shed light on the evolutionary process of jaw movement towards the mammalian condition in more detail. PMID:29186178

  17. Workshop on Condition Based Maintenance Held in Atlantic Beach, North Carolina on November 15 - 17, 1993

    DTIC Science & Technology

    1993-11-17

    pounds of Torque Over Three Minutes Continuous Operation IYMCO1A 14 DMAE Corporation C-130 Engine Gearbox January 19925 Stress Wave Analysis - I in’. I...FaUi.O The CBM needs associated with surface initiated failure mechanisms can be divided into I singular defects and low (h/a) operation. Singular defec-t...These include nicks, scratches, corrosion pits and dents caused by third’ body particles (hard or soft). These defects cause local stress risers

  18. Investigation into the mechanisms of closed three-body abrasive wear

    NASA Astrophysics Data System (ADS)

    Dwyer-Joyce, R. S.; Sayles, R. S.; Ioannides, E.

    1994-06-01

    Contacting components frequently fail by abrasion caused by solid contaminants in the lubricant. This process can be classified as a closed three-body abrasive wear process. The mechanisms by which trapped particles cause material removal are not fully understood. This paper describes tests using model elastohydrodynamic contacts to study these mechanisms. An optical elastohydrodynamic lubrication rig has been used to study the deformation and fracture of ductile and brittle lubricant-borne debris. A ball-on-disk machine was used to study the behavior of the particles in partially sliding contacts. Small diamond particles were used as abrasives since these were thought not to break down in the contact; wear could then be directly related to particles of a known size. The particles were found to embed in the softer surface and to scratch the harder. The mass of material worn from the ball surface was approximately proportional to the particle sliding distance and abrasive concentration. Small particles tumbled through the contact, while larger particles ploughed. Mass loss was found to increase with abrasive particle size. Individual abrasion scratches have been measured and related to the abrading particle. A simple model of the abrasive process has been developed and compared with experimental data. The discrepancies are thought to be the result of the uncertainty about the entrainment of particles into the contact.

  19. Hydrogen sulfide-induced itch requires activation of Cav3.2 T-type calcium channel in mice

    PubMed Central

    Wang, Xue-Long; Tian, Bin; Huang, Ya; Peng, Xiao-Yan; Chen, Li-Hua; Li, Jun-Cheng; Liu, Tong

    2015-01-01

    The contributions of gasotransmitters to itch sensation are largely unknown. In this study, we aimed to investigate the roles of hydrogen sulfide (H2S), a ubiquitous gasotransmitter, in itch signaling. We found that intradermal injection of H2S donors NaHS or Na2S, but not GYY4137 (a slow-releasing H2S donor), dose-dependently induced scratching behavior in a μ-opioid receptor-dependent and histamine-independent manner in mice. Interestingly, NaHS induced itch via unique mechanisms that involved capsaicin-insensitive A-fibers, but not TRPV1-expressing C-fibers that are traditionally considered for mediating itch, revealed by depletion of TRPV1-expressing C-fibers by systemic resiniferatoxin treatment. Moreover, local application of capsaizapine (TRPV1 blocker) or HC-030031 (TRPA1 blocker) had no effects on NaHS-evoked scratching. Strikingly, pharmacological blockade and silencing of Cav3.2 T-type calcium channel by mibefradil, ascorbic acid, zinc chloride or Cav3.2 siRNA dramatically decreased NaHS-evoked scratching. NaHS induced robust alloknesis (touch-evoked itch), which was inhibited by T-type calcium channels blocker mibefradil. Compound 48/80-induced itch was enhanced by an endogenous precursor of H2S (L-cysteine) but attenuated by inhibitors of H2S-producing enzymes cystathionine γ-lyase and cystathionine β-synthase. These results indicated that H2S, as a novel nonhistaminergic itch mediator, may activates Cav3.2 T-type calcium channel, probably located at A-fibers, to induce scratching and alloknesis in mice. PMID:26602811

  20. Glycyrrhetinic acid prevents cutaneous scratching behavior in mice elicited by substance P or PAR-2 agonist.

    PubMed

    Akasaka, Yuko; Yoshida, Tsuyoshi; Tsukahara, Michiko; Hatta, Akira; Inoue, Hideo

    2011-11-16

    Although glycyrrhetinic acid (GA) has been used for the prevention of itch in chronic dermatitis, the mechanism underlying the antipruritic effects of GA is still unclear. Recently, several mediators other than histamine, such as substance P and tryptase, were found to participate in chronic itch. Here, we investigated the effect of GA on pruritus induced by various pruritic agents including histamine in mice. We also determined the level of leukotriene (LT)B(4) in mouse skin injected with substance P in an effort to uncover part of the antipruritic mechanism of GA. Scratching events were counted for 10 min after intradermal injection of histamine, substance P (100 nmol per site each), protease-activated receptor-2 (PAR-2) agonistic peptide (50 nmol per site), or LTB(4) (0.03 nmol per site) with or without GA (4 nmol per site) into male ICR mice. Levels of LTB(4) in the skin after injection of substance P were determined by ELISA. GA did not suppress scratching behavior induced by histamine and LTB(4), but markedly and dose-dependently suppressed that induced by substance P and PAR-2 agonistic peptide. LTB(4) levels in skin elevated by substance P were lowered by GA. These data support the efficacy of GA in counteracting itch in chronic dermatitis because GA reduced scratching behavior induced by substance P and PAR-2 agonistic peptide. GA may exert antipruritic effects via inhibition of LTB(4) production in skin. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. A possible role for CD26/DPPIV enzyme activity in the regulation of psoriatic pruritus.

    PubMed

    Komiya, Eriko; Hatano, Ryo; Otsuka, Haruna; Itoh, Takumi; Yamazaki, Hiroto; Yamada, Taketo; Dang, Nam H; Tominaga, Mitsutoshi; Suga, Yasushi; Kimura, Utako; Takamori, Kenji; Morimoto, Chikao; Ohnuma, Kei

    2017-06-01

    Psoriasis (PSO) is one of the most common chronic inflammatory skin diseases, and pruritus affects approximately 60-90% of patients with PSO. However, the pathogenesis of pruritus in PSO remains unclear. Dipeptidyl peptidase IV (DPPIV) enzyme activity is involved in the regulation of peptide hormones, chemokines and neurotransmitters. Our aim is to evaluate for a potential association between DPPIV and an increased risk of pruritus, and to identify possible underlying treatment targets in affected patients. Utilizing clinical serum samples of PSO patients and in vivo experimental pruritus models, we evaluated for a potential association between DPPIV and an increased risk for pruritus, and attempted to identify possible underlying treatment targets in pruritus of PSO. We first showed that levels of DPPIV enzyme activity in sera of patients with PSO were significantly increased compared to those of healthy controls. We next evaluated levels of substance-P (SP), which is a neurotransmitter for pruritus and a substrate for DPPIV enzyme. Truncated form SP cleaved by DPPIV was significantly increased in sera of PSO. In an in vivo pruritus model induced by SP, scratching was decreased by treatment with a DPPIV inhibitor. Moreover, DPPIV-knockout mice showed attenuation of scratching induced by SP. Finally, scratching was decreased following the administration of a DPPIV inhibitor in an imiquimod-induced PSO model. On the other hand, scratching induced by imiquimod was increased in DPPIV overexpressing-mice. These results suggest that inhibition of DPPIV enzyme activity regulates pruritus in PSO. Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

  2. AQP5 is differentially regulated in astrocytes during metabolic and traumatic injuries.

    PubMed

    Chai, Rui Chao; Jiang, Jiao Hua; Wong, Ann Yuen Kwan; Jiang, Feng; Gao, Kai; Vatcher, Greg; Hoi Yu, Albert Cheung

    2013-10-01

    Water movement plays vital roles in both physiological and pathological conditions in the brain. Astrocytes are responsible for regulating this water movement and are the major contributors to brain edema in pathological conditions. Aquaporins (AQPs) in astrocytes play critical roles in the regulation of water movement in the brain. AQP1, 3, 4, 5, 8, and 9 have been reported in the brain. Compared with AQP1, 4, and 9, AQP3, 5, and 8 are less studied. Among the lesser known AQPs, AQP5, which has multiple functions identified outside the central nervous system, is also indicated to be involved in hypoxia injury in astrocytes. In our study, AQP5 expression could be detected both in primary cultures of astrocytes and neurons, and AQP5 expression in astrocytes was confirmed in 1- to 4-week old primary cultures of astrocytes. AQP5 was localized on the cytoplasmic membrane and in the cytoplasm of astrocytes. AQP5 expression was downregulated during ischemia treatment and upregulated after scratch-wound injury, which was also confirmed in a middle cerebral artery occlusion model and a stab-wound injury model in vivo. The AQP5 increased after scratch injury was polarized to the migrating processes and cytoplasmic membrane of astrocytes in the leading edge of the scratch-wound, and AQP5 over-expression facilitated astrocyte process elongation after scratch injury. Taken together, these results indicate that AQP5 might be an important water channel in astrocytes that is differentially expressed during various brain injuries. Copyright © 2013 Wiley Periodicals, Inc.

  3. Tribological and mechanical performance evaluation of metal prosthesis components manufactured via metal injection molding.

    PubMed

    Melli, Virginia; Juszczyk, Mateusz; Sandrini, Enrico; Bolelli, Giovanni; Bonferroni, Benedetta; Lusvarghi, Luca; Cigada, Alberto; Manfredini, Tiziano; De Nardo, Luigi

    2015-01-01

    The increasing number of total joint replacements, in particular for the knee joint, has a growing impact on the healthcare system costs. New cost-saving manufacturing technologies are being explored nowadays. Metal injection molding (MIM) has already demonstrated its suitability for the production of CoCrMo alloy tibial trays, with a significant reduction in production costs, by holding both corrosion resistance and biocompatibility. In this work, mechanical and tribological properties were evaluated on tibial trays obtained via MIM and conventional investment casting. Surface hardness and wear properties were evaluated through Vickers hardness, scratch and pin on disk tests. The MIM and cast finished tibial trays were then subjected to a fatigue test campaign in order to obtain their fatigue load limit at 5 millions cycles following ISO 14879-1 directions. CoCrMo cast alloy exhibited 514 HV hardness compared to 335 HV of MIM alloy, furthermore it developed narrower scratches with a higher tendency towards microploughing than microcutting, in comparison to MIM CoCrMo. The observed fatigue limits were (1,766 ± 52) N for cast tibial trays and (1,625 ± 44) N for MIM ones. Fracture morphologies pointed out to a more brittle behavior of MIM microstructure. These aspects were attributed to the absence of a fine toughening and surface hardening carbide dispersion in MIM grains. Nevertheless, MIM tibial trays exhibited a fatigue limit far beyond the 900 N of maximum load prescribed by ISO and ASTM standards for the clinical application of these devices.

  4. Reconciling Scratch Space Consumption, Exposure, and Volatility to Achieve Timely Staging of Job Input Data

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

    Monti, Henri; Butt, Ali R; Vazhkudai, Sudharshan S

    2010-04-01

    Innovative scientific applications and emerging dense data sources are creating a data deluge for high-end computing systems. Processing such large input data typically involves copying (or staging) onto the supercomputer's specialized high-speed storage, scratch space, for sustained high I/O throughput. The current practice of conservatively staging data as early as possible makes the data vulnerable to storage failures, which may entail re-staging and consequently reduced job throughput. To address this, we present a timely staging framework that uses a combination of job startup time predictions, user-specified intermediate nodes, and decentralized data delivery to coincide input data staging with job start-up.more » By delaying staging to when it is necessary, the exposure to failures and its effects can be reduced. Evaluation using both PlanetLab and simulations based on three years of Jaguar (No. 1 in Top500) job logs show as much as 85.9% reduction in staging times compared to direct transfers, 75.2% reduction in wait time on scratch, and 2.4% reduction in usage/hour.« less

  5. Peripheral gabapentin regulates mosquito allergy-induced itch in mice.

    PubMed

    Akiyama, Tasuku; Andoh, Tsugunobu; Ohtsuka, Eiji; Nojima, Hiroshi; Ouchi, Hidekazu; Takahata, Hiroki; Kuraishi, Yasushi

    2018-05-26

    The antipruritic activity of gabapentin, an anticonvulsant, was studied in a mouse model of allergic itch. In mice sensitized by an extract of the salivary glands of the mosquito (ESGM), an intradermal injection of ESGM elicited scratching and increased peripheral nerve firing. Oral or intradermal administration of gabapentin at the ESGM injection site inhibited ESGM-induced scratching and peripheral nerve firing. However, gabapentin did not affect histamine-induced scratching. The distributions of immunoreactivity to the voltage-dependent calcium channel α 2 δ-1 subunit, a site of gabapentin action, and the histamine H 1 receptor differed in the mouse dorsal root ganglia. The α 2 δ-1 subunit was mainly found in neurons that were 15-20 µm in diameter, whereas the H 1 receptor was mainly in 20-30 µm neurons. In addition, α 2 δ-1 subunit immunoreactivity co-localized with that of transient receptor potential vanilloid 1 (TRPV1). These results suggest that gabapentin regulates allergic itch by acting on the calcium channel α 2 δ-1 subunit in peripheral TRPV1-positive neurons. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Factors affecting the outcome of "endometrial scratch" in women with recurrent implantation failure.

    PubMed

    Coughlan, Carol; Yuan, Xi; Demirol, Aygul; Ledger, William; Li, Tin Chiu

    2014-01-01

    To examine factors affecting the outcome of the endometrial scratch in women with recurrent implantation failure. A total of 57 eligible patients with a history of recurrent implantation failure underwent an endometrial biopsy in the luteal phase of the menstrual cycle in the month immediately preceding the embryo transfer cycle. The comparative group consisted of a retrospective cohort of 66 women with recurrent implantation failure but without endometrial biopsy. There were no significant differences between the intervention and control groups in terms of age, follicle-stimulating hormone (FSH), free androgen index, anti-Müllerian hormone, body mass index, the number of embryos transferred, and the number of embryo transfer cycles. The clinical pregnancy rate in the intervention group (53%) was significantly (p < 0.001) higher than that of the control group (15%). The only predictive factor was FSH. Women with FSH < or =10 IU/L had a pregnancy rate of 57.8%, significantly (p < 0.05) higher than that (20%) of women with FSH >10 IU/L. Women with a normal FSH are more likely to derive benefit from endometrial scratch.

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

    Zhu, Bo; Zhao, Hongwei, E-mail: hwzhao@jlu.edu.cn, E-mail: khl69@163.com; Zhao, Dan

    It has always been a critical issue to understand the material removal behavior of Vibration-Assisted Machining (VAM), especially on atomic level. To find out the effects of vibration frequency on material removal response, a three-dimensional molecular dynamics (MD) model has been established in this research to investigate the effects of scratched groove, crystal defects on the surface quality, comparing with the Von Mises shear strain and tangential force in simulations during nano-scratching process. Comparisons are made among the results of simulations from different vibration frequency with the same scratching feed, depth, amplitude and crystal orientation. Copper potential in this simulationmore » is Embedded-Atom Method (EAM) potential. Interaction between copper and carbon atoms is Morse potential. Simulational results show that higher frequency can make groove smoother. Simulation with high frequency creates more dislocations to improve the machinability of copper specimen. The changing frequency does not have evident effects on Von Mises shear strain. Higher frequency can decrease the tangential force to reduce the consumption of cutting energy and tool wear. In conclusion, higher vibration frequency in VAM on mono-crystalline copper has positive effects on surface finish, machinablility and tool wear reduction.« less

  8. Regenerative responses after mild heart injuries for cardiomyocyte proliferation in zebrafish

    PubMed Central

    Itou, Junji; Akiyama, Ryutaro; Pehoski, Steve; Yu, Xiaodan; Kawakami, Hiroko; Kawakami, Yasuhiko

    2014-01-01

    Background The zebrafish heart regenerates after various severe injuries. Common processes of heart regeneration are cardiomyocyte proliferation, activation of epicardial tissue and neovascularization. In order to further characterize heart regeneration processes, we introduced milder injuries and compared responses to those induced by ventricular apex resection, a widely used injury method. We used scratching of the ventricular surface and puncturing of the ventricle with a fine tungsten needle as injury inducing techniques. Results Scratching the ventricular surface induced subtle cardiomyocyte proliferation and responses of the epicardium. Endothelial cell accumulation was limited to the surface of the heart. Ventricular puncture induced cardiomyocyte proliferation, endocardial and epicardial activation and neo-vascularization, similar to the resection method. However, the degree of the responses was milder, correlating with milder injury. Sham operation induced epicardial aldh1a2 expression but not tbx18 and WT1. Conclusions Puncturing the ventricle induces responses equivalent to resection at milder degrees in a shorter time frame and would be used as simple injury model. Scratching the ventricle did not induce heart regeneration and would be used for studying wound responses to epicardium. PMID:25074230

  9. Arctigenin Confers Neuroprotection Against Mechanical Trauma Injury in Human Neuroblastoma SH-SY5Y Cells by Regulating miRNA-16 and miRNA-199a Expression to Alleviate Inflammation.

    PubMed

    Song, Jie; Li, Na; Xia, Yang; Gao, Zhong; Zou, Sa-Feng; Yan, Yu-Hui; Li, Shao-Heng; Wang, Yue; Meng, Ya-Kun; Yang, Jing-Xian; Kang, Ting-Guo

    2016-09-01

    Mechanical trauma injury is a severe insult to neural cells. Subsequent secondary injury involves the release of inflammatory factors that have dramatic consequences for undamaged cells, leading to normal cell death after the initial injury. The present study investigated the capacity for arctigenin (ARC) to prevent secondary effects and evaluated the mechanism underlying the action of microRNA (miRNA)-199a and miRNA-16 in a mechanical trauma injury (MTI) model using SH-SY5Y cells in vitro. SH-SY5Y cells are often applied to in vitro models of neuronal function and differentiation. Recently, miRNAs have been demonstrated to play a crucial role in NF-κB and cholinergic signaling, which can regulate inflammation. The cell model was established by scratch-induced injury of human SH-SY5Y cells, which mimics the characteristics of MTI. A cell counting kit-8 (CCK-8), terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and immunocytochemistry were used to measure cell viability. Enzyme-linked immunosorbent assay (ELISA) was used to evaluate the inflammatory cytokine and cholinesterase (CHE) content. The lactate dehydrogenase (LDH) content was measured to assess the degree of cell injury. The mRNA levels were measured by RT-PCR to analyze ARC's mechanism of action. miRNA inhibitors and mimics were used to inhibit and strengthen the expression of miRNAs. Protein expression was detected by western blotting analysis. ARC treatment reduced the TNF-α and IL-6 levels as well as the number of TUNEL+ apoptotic SH-SY5Y cells surrounding the scratch and increased the IL-10 level compared to the controls. ARC attenuated the increase of the cell damage degree and LDH content induced by scratching, indicating increased cell survival. Mechanistic studies showed that ARC upregulated the miRNA-16 and miRNA-199a levels to reduce upstream protein (IKKα and IKKβ) expression and inhibit NF-κB signaling pathway activity; moreover, the increased miRNA-199a suppresses cholinesterases to increase cholinergic signaling, resulting in decreased expression of proinflammatory cytokines. ARC treatment confers protection for SH-SY5Y cells through positive regulation of miRNA expression, thereby reducing the inflammatory response. In turn, these effects accelerate injury repair in the scratch-induced injury model. These results might provide insights into the pharmacological role of ARC in anti-inflammation and neuroprotection in neural cells.

  10. Dietary reconstruction from trace element analysis and dental microwear in an Early Medieval population from Gán (Galanta district, Slovakia).

    PubMed

    Bodoriková, Silvia; Tibenská, Kristína Domonkosová; Katina, Stanislav; Uhrová, Petra; Dörnhöferová, Michaela; Takács, Michal; Urminský, Jozef

    2013-01-01

    The aim of the study was to determine the diet of an historical human population using the trace elements in dental tissues and dental buccal microwear. Although 38 individuals had been buried in the cemetery, preservation of the remains did not allow analysis of all of them. A total of 13 individuals were analysed, of which the samples for trace-element analysis consisted of 12 permanent premolars from 12 individuals. Buccal microwear was studied in a sample of nine teeth from nine individuals. Both trace-element and microwear analyses were performed on eight individuals. All analyzed teeth were intact, with fully developed roots, without dental calculus and macro-abrasion. Concentrations of Sr, Zn, and Ca, and their ratios, were used to determine the relative proportions of plant and animal protein in the diet. Samples were analyzed using optical emission spectrometry with inductively coupled plasma. The values of the Sr and Zn concentrations indicate that a diet of the investigated population was of a mixed character with approximately the same proportion of plants and meat in their food. Buccal microwear was studied in molds ofbuccal surfaces and observed at 100x magnification with a scanning electron microscope (SEM). Length and orientation of striations were determined with the SigmaScan Pro 5.0 image analysis program. The results obtained from microwear analysis correspond with those from trace-element analysis and showed that the population consumed a mixed diet. The density of the scratches indicates that the diet contained a considerable vegetable component. The high number of vertical scratches and their high average length suggest that individuals also consumed a large portion of meat. The results of both analyses showed that there were also individuals whose diet had probably been poor, i.e. richer in animal protein, which probably could be related to their health or social status in the population.

  11. The functional and palaeoecological implications of tooth morphology and wear for the megaherbivorous dinosaurs from the Dinosaur Park Formation (upper Campanian) of Alberta, Canada.

    PubMed

    Mallon, Jordan C; Anderson, Jason S

    2014-01-01

    Megaherbivorous dinosaurs were exceptionally diverse on the Late Cretaceous island continent of Laramidia, and a growing body of evidence suggests that this diversity was facilitated by dietary niche partitioning. We test this hypothesis using the fossil megaherbivore assemblage from the Dinosaur Park Formation (upper Campanian) of Alberta as a model. Comparative tooth morphology and wear, including the first use of quantitative dental microwear analysis in the context of Cretaceous palaeosynecology, are used to infer the mechanical properties of the foods these dinosaurs consumed. The phylliform teeth of ankylosaurs were poorly adapted for habitually processing high-fibre plant matter. Nevertheless, ankylosaur diets were likely more varied than traditionally assumed: the relatively large, bladed teeth of nodosaurids would have been better adapted to processing a tougher, more fibrous diet than the smaller, cusp-like teeth of ankylosaurids. Ankylosaur microwear is characterized by a preponderance of pits and scratches, akin to modern mixed feeders, but offers no support for interspecific dietary differences. The shearing tooth batteries of ceratopsids are much better adapted to high-fibre herbivory, attested by their scratch-dominated microwear signature. There is tentative microwear evidence to suggest differences in the feeding habits of centrosaurines and chasmosaurines, but statistical support is not significant. The tooth batteries of hadrosaurids were capable of both shearing and crushing functions, suggestive of a broad dietary range. Their microwear signal overlaps broadly with that of ankylosaurs, and suggests possible dietary differences between hadrosaurines and lambeosaurines. Tooth wear evidence further indicates that all forms considered here exhibited some degree of masticatory propaliny. Our findings reveal that tooth morphology and wear exhibit different, but complimentary, dietary signals that combine to support the hypothesis of dietary niche partitioning. The inferred mechanical and dietary patterns appear constant over the 1.5 Myr timespan of the Dinosaur Park Formation megaherbivore chronofauna, despite continual species turnover.

  12. The Functional and Palaeoecological Implications of Tooth Morphology and Wear for the Megaherbivorous Dinosaurs from the Dinosaur Park Formation (Upper Campanian) of Alberta, Canada

    PubMed Central

    Mallon, Jordan C.; Anderson, Jason S.

    2014-01-01

    Megaherbivorous dinosaurs were exceptionally diverse on the Late Cretaceous island continent of Laramidia, and a growing body of evidence suggests that this diversity was facilitated by dietary niche partitioning. We test this hypothesis using the fossil megaherbivore assemblage from the Dinosaur Park Formation (upper Campanian) of Alberta as a model. Comparative tooth morphology and wear, including the first use of quantitative dental microwear analysis in the context of Cretaceous palaeosynecology, are used to infer the mechanical properties of the foods these dinosaurs consumed. The phylliform teeth of ankylosaurs were poorly adapted for habitually processing high-fibre plant matter. Nevertheless, ankylosaur diets were likely more varied than traditionally assumed: the relatively large, bladed teeth of nodosaurids would have been better adapted to processing a tougher, more fibrous diet than the smaller, cusp-like teeth of ankylosaurids. Ankylosaur microwear is characterized by a preponderance of pits and scratches, akin to modern mixed feeders, but offers no support for interspecific dietary differences. The shearing tooth batteries of ceratopsids are much better adapted to high-fibre herbivory, attested by their scratch-dominated microwear signature. There is tentative microwear evidence to suggest differences in the feeding habits of centrosaurines and chasmosaurines, but statistical support is not significant. The tooth batteries of hadrosaurids were capable of both shearing and crushing functions, suggestive of a broad dietary range. Their microwear signal overlaps broadly with that of ankylosaurs, and suggests possible dietary differences between hadrosaurines and lambeosaurines. Tooth wear evidence further indicates that all forms considered here exhibited some degree of masticatory propaliny. Our findings reveal that tooth morphology and wear exhibit different, but complimentary, dietary signals that combine to support the hypothesis of dietary niche partitioning. The inferred mechanical and dietary patterns appear constant over the 1.5 Myr timespan of the Dinosaur Park Formation megaherbivore chronofauna, despite continual species turnover. PMID:24918431

  13. Robust wafer identification recognition based on asterisk-shape filter and high-low score comparison method.

    PubMed

    Hsu, Wei-Chih; Yu, Tsan-Ying; Chen, Kuan-Liang

    2009-12-10

    Wafer identifications (wafer ID) can be used to identify wafers from each other so that wafer processing can be traced easily. Wafer ID recognition is one of the problems of optical character recognition. The process to recognize wafer IDs is similar to that used in recognizing car license-plate characters. However, due to some unique characteristics, such as the irregular space between two characters and the unsuccessive strokes of wafer ID, it will not get a good result to recognize wafer ID by directly utilizing the approaches used in car license-plate character recognition. Wafer ID scratches are engraved by a laser scribe almost along the following four fixed directions: horizontal, vertical, plus 45 degrees , and minus 45 degrees orientations. The closer to the center line of a wafer ID scratch, the higher the gray level will be. These and other characteristics increase the difficulty to recognize the wafer ID. In this paper a wafer ID recognition scheme based on an asterisk-shape filter and a high-low score comparison method is proposed to cope with the serious influence of uneven luminance and make recognition more efficiently. Our proposed approach consists of some processing stages. Especially in the final recognition stage, a template-matching method combined with stroke analysis is used as a recognizing scheme. This is because wafer IDs are composed of Semiconductor Equipment and Materials International (SEMI) standard Arabic numbers and English alphabets, and thus the template ID images are easy to obtain. Furthermore, compared with the approach that requires prior training, such as a support vector machine, which often needs a large amount of training image samples, no prior training is required for our approach. The testing results show that our proposed scheme can efficiently and correctly segment out and recognize the wafer ID with high performance.

  14. Enabling Wide-Scale Computer Science Education through Improved Automated Assessment Tools

    NASA Astrophysics Data System (ADS)

    Boe, Bryce A.

    There is a proliferating demand for newly trained computer scientists as the number of computer science related jobs continues to increase. University programs will only be able to train enough new computer scientists to meet this demand when two things happen: when there are more primary and secondary school students interested in computer science, and when university departments have the resources to handle the resulting increase in enrollment. To meet these goals, significant effort is being made to both incorporate computational thinking into existing primary school education, and to support larger university computer science class sizes. We contribute to this effort through the creation and use of improved automated assessment tools. To enable wide-scale computer science education we do two things. First, we create a framework called Hairball to support the static analysis of Scratch programs targeted for fourth, fifth, and sixth grade students. Scratch is a popular building-block language utilized to pique interest in and teach the basics of computer science. We observe that Hairball allows for rapid curriculum alterations and thus contributes to wide-scale deployment of computer science curriculum. Second, we create a real-time feedback and assessment system utilized in university computer science classes to provide better feedback to students while reducing assessment time. Insights from our analysis of student submission data show that modifications to the system configuration support the way students learn and progress through course material, making it possible for instructors to tailor assignments to optimize learning in growing computer science classes.

  15. New Specimens of the Rare Taeniodont Wortmania (Mammalia: Eutheria) from the San Juan Basin of New Mexico and Comments on the Phylogeny and Functional Morphology of “Archaic” Mammals

    PubMed Central

    Williamson, Thomas E.; Brusatte, Stephen L.

    2013-01-01

    Background Taeniodonta is a clade of Late Cretaceous – Paleogene mammals remarkable for their relatively extreme cranial, dental, and postcranial adaptations and notable for being among the first mammals to achieve relatively large size following the Cretaceous-Paleogene mass extinction. Previous workers have hypothesized that taeniodonts can be divided into two clades: Conoryctidae, a group of small-bodied taeniodonts with supposedly “generalized” postcranial skeletons, and Stylinodontidae, a group of large-bodied, robust animals with massive forelimbs and claws adapted for scratch-digging. However, many taeniodont taxa are poorly known and few are represented by postcranial material, leaving many details about their anatomy, biology, and evolution ambiguous. Methodology/Principal Findings In this paper, we describe three new specimens of the rare taxon Wortmaniaotariidens from the early Paleocene (Puercan) of New Mexico. Among these specimens is one that includes remarkably complete cranial and dental material, including associated upper and lower teeth, and another that consists of partial forelimbs. These specimens allow for an updated anatomical description of this unusual taxon, supply new data for phylogenetic analyses, and enable a more constrained discussion of taeniodont biology and functional morphology. Conclusions/Significance The new specimen of Wortmania that includes associated upper and lower teeth indicates that previous interpretations of the upper dentition of this taxon were not accurate and the taxon Robertschochiasullivani is a junior synonym of W . otariidens . New specimens that include partial forelimbs indicate that Wortmania is very similar to later, large-bodied taeniodonts, with marked and distinctive adaptations for scratch-digging. Comparisons with other taeniodont taxa that include postcranial material suggest that all taeniodonts may have had scratch-digging adaptations. A phylogenetic analysis shows that Schowalteria and Onychodectes are basal taeniodonts, Stylinodontidae (including Wortmania) is monophyletic, and a monophyletic Conoryctidae (but not including Onychodectes) is only recovered when certain characters are ordered. PMID:24098738

  16. New specimens of the rare taeniodont Wortmania (Mammalia: Eutheria) from the San Juan Basin of New Mexico and comments on the phylogeny and functional morphology of "archaic" mammals.

    PubMed

    Williamson, Thomas E; Brusatte, Stephen L

    2013-01-01

    Taeniodonta is a clade of Late Cretaceous-Paleogene mammals remarkable for their relatively extreme cranial, dental, and postcranial adaptations and notable for being among the first mammals to achieve relatively large size following the Cretaceous-Paleogene mass extinction. Previous workers have hypothesized that taeniodonts can be divided into two clades: Conoryctidae, a group of small-bodied taeniodonts with supposedly "generalized" postcranial skeletons, and Stylinodontidae, a group of large-bodied, robust animals with massive forelimbs and claws adapted for scratch-digging. However, many taeniodont taxa are poorly known and few are represented by postcranial material, leaving many details about their anatomy, biology, and evolution ambiguous. In this paper, we describe three new specimens of the rare taxon Wortmania otariidens from the early Paleocene (Puercan) of New Mexico. Among these specimens is one that includes remarkably complete cranial and dental material, including associated upper and lower teeth, and another that consists of partial forelimbs. These specimens allow for an updated anatomical description of this unusual taxon, supply new data for phylogenetic analyses, and enable a more constrained discussion of taeniodont biology and functional morphology. The new specimen of Wortmania that includes associated upper and lower teeth indicates that previous interpretations of the upper dentition of this taxon were not accurate and the taxon Robertschochia sullivani is a junior synonym of W. otariidens. New specimens that include partial forelimbs indicate that Wortmania is very similar to later, large-bodied taeniodonts, with marked and distinctive adaptations for scratch-digging. Comparisons with other taeniodont taxa that include postcranial material suggest that all taeniodonts may have had scratch-digging adaptations. A phylogenetic analysis shows that Schowalteria and Onychodectes are basal taeniodonts, Stylinodontidae (including Wortmania) is monophyletic, and a monophyletic Conoryctidae (but not including Onychodectes) is only recovered when certain characters are ordered.

  17. Surface modifications with Lissajous trajectories using atomic force microscopy

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

    Cai, Wei; Yao, Nan, E-mail: nyao@princeton.edu

    2015-09-14

    In this paper, we report a method for atomic force microscopy surface modifications with single-tone and multiple-resolution Lissajous trajectories. The tip mechanical scratching experiments with two series of Lissajous trajectories were carried out on monolayer films. The scratching processes with two scan methods have been illustrated. As an application, the tip-based triboelectrification phenomenon on the silicon dioxide surface with Lissajous trajectories was investigated. The triboelectric charges generated within the tip rubbed area on the surface were characterized in-situ by scanning Kelvin force microscopy. This method would provide a promising and cost-effective approach for surface modifications and nanofabrication.

  18. Cat-scratch disease. Subtle vertebral bone marrow abnormalities demonstrated by MR imaging and radionuclide bone scan.

    PubMed

    Wilson, J D; Castillo, M

    1995-01-01

    Cat-scratch disease (CSD) is a benign, self-limited cause of lymphadenitis occurring mainly in children and young adults. Its etiology is a delicate, small gram-negative pleomorphic bacillus. Less common manifestations of CSD are seen in 5% of patients and include Parinaud's oculoglandular syndrome (with enlargement of the preauricular nodes), parotid gland enlargement, encephalitis, radiculopathy, pneumonitis, erythema nodosum, thrombocytopenia, and lytic bone lesions. We describe a patient in whom magnetic resonance imaging initially detected subtle vertebral bone marrow abnormalities that correlated with the site of abnormality on a subsequent radionuclide bone scan.

  19. Cat-scratch disease and bone scintigraphy.

    PubMed

    Ismaili-Alaoui, Nadia; Vuong, Valerie; Marcu-Marin, M; Sergent-Alaoui, Aline; Chevallier, Bertrand; de Labriolle-Vaylet, Claire

    2012-08-01

    Cat-scratch disease is a bacterial infection caused by Bartonella henselae. Bone involvement is rare. We describe the case of a 7-year-old boy with a systemic form of the disease. He presented with a 15-day history of fever, altered general condition, weight loss and cough, associated with back pain, and right-sided coxalgia. Bone scintigraphy with Tc-99m hydroxymethylene diphosphonate showed spinal involvement, the iliac crest, the right ankle, and the right first metatarsal. Magnetic resonance imaging confirmed these locations. He was positive for anti-Bartonella henselae. The fever regressed before treatment with rifampicin began, and he made a full recovery.

  20. Fiber-optical switch using cam-micromotor driven by scratch drive actuators

    NASA Astrophysics Data System (ADS)

    Kanamori, Y.; Aoki, Y.; Sasaki, M.; Hosoya, H.; Wada, A.; Hane, K.

    2005-01-01

    We fabricated a 1 × 1 fiber-optic switch using a cam-micromotor driven by scratch drive actuators (SDAs). Using the cam-micromotor, mechanical translation and precise positioning of an optical fiber were performed. An optical fiber of diameter 50 µm was bent and pushed out with a cam-mechanism driven by the SDAs fabricated by surface micromachining. The maximum rotation speed of the cam-micromotor was 7.5 rpm at a driving frequency of 1.5 kHz. The transient time of the switch to attenuate coupling efficiency less than -40 dB was around 10 ms.

  1. [Cat-scratch disease with bone compromise: atypical manifestation].

    PubMed

    Rodríguez C, Magdalena; Giachetto L, Gustavo; Cuneo E, Alejandro; Gutiérrez B, María del C; Shimchack R, Mario; Pírez G, M Catalina

    2009-08-01

    Fever, headache, myalgias and lymphadenopathy are characteristic manifestations of cat-scratch disease but other less common findings are described in 2 to 10% of cases. We report two children that presented with hepatosplenic abscesses and bone involvement. One child, had multiple areas of increased uptake in the bone scintigram with a positive serology (IgG > 1/256, IgM slightly positive). The second child had destruction of the L2 vertebral body that compromised the channel and right foramen as visualized by MRI. In both cases, bacilli were observed in the bone biopsy by Warthing-Starry stain.

  2. [A new machinability test machine and the machinability of composite resins for core built-up].

    PubMed

    Iwasaki, N

    2001-06-01

    A new machinability test machine especially for dental materials was contrived. The purpose of this study was to evaluate the effects of grinding conditions on machinability of core built-up resins using this machine, and to confirm the relationship between machinability and other properties of composite resins. The experimental machinability test machine consisted of a dental air-turbine handpiece, a control weight unit, a driving unit of the stage fixing the test specimen, and so on. The machinability was evaluated as the change in volume after grinding using a diamond point. Five kinds of core built-up resins and human teeth were used in this study. The machinabilities of these composite resins increased with an increasing load during grinding, and decreased with repeated grinding. There was no obvious correlation between the machinability and Vickers' hardness; however, a negative correlation was observed between machinability and scratch width.

  3. Application of Contact Mode AFM to Manufacturing Processes

    NASA Astrophysics Data System (ADS)

    Giordano, Michael A.; Schmid, Steven R.

    A review of the application of contact mode atomic force microscopy (AFM) to manufacturing processes is presented. A brief introduction to common experimental techniques including hardness, scratch, and wear testing is presented, with a discussion of challenges in the extension of manufacturing scale investigations to the AFM. Differences between the macro- and nanoscales tests are discussed, including indentation size effects and their importance in the simulation of processes such as grinding. The basics of lubrication theory are presented and friction force microscopy is introduced as a method of investigating metal forming lubrication on the nano- and microscales that directly simulates tooling/workpiece asperity interactions. These concepts are followed by a discussion of their application to macroscale industrial manufacturing processes and direct correlations are made.

  4. Protein contact dermatitis: allergens, pathogenesis, and management.

    PubMed

    Levin, Cheryl; Warshaw, Erin

    2008-01-01

    Protein contact dermatitis is an allergic skin reaction induced principally by proteins of either animal or plant origin. The clinical presentation is that of a chronic dermatitis, and it is often difficult to differentiate between allergic contact dermatitis and other eczematous dermatoses. One distinguishing clinical feature is that acute flares of pruritus, urticaria, edema, or vesiculation are noted minutes after contact with the causative substances. Additionally, the patch-test result is typically negative, and the scratch- or prick-test result is positive. The pathogenesis of protein contact dermatitis is unclear but may involve a type I (immunoglobulin E [IgE], immediate) hypersensitivity reaction, type IV (cell-mediated delayed) hypersensitivity reaction, and/or a delayed reaction due to IgE-bearing Langerhans' cells. Management involves avoidance of the allergen.

  5. The AST3 controlling and operating software suite for automatic sky survey

    NASA Astrophysics Data System (ADS)

    Hu, Yi; Shang, Zhaohui; Ma, Bin; Hu, Keliang

    2016-07-01

    We have developed a specialized software package, called ast3suite, to achieve the remote control and automatic sky survey for AST3 (Antarctic Survey Telescope) from scratch. It includes several daemon servers and many basic commands. Each program does only one single task, and they work together to make AST3 a robotic telescope. A survey script calls basic commands to carry out automatic sky survey. Ast3suite was carefully tested in Mohe, China in 2013 and has been used at Dome, Antarctica in 2015 and 2016 with the real hardware for practical sky survey. Both test results and practical using showed that ast3suite had worked very well without any manual auxiliary as we expected.

  6. Test Method Variability in Slow Crack Growth Properties of Sealing Glasses

    NASA Technical Reports Server (NTRS)

    Salem, J. A.; Tandon, R.

    2010-01-01

    The crack growth properties of several sealing glasses were measured by using constant stress rate testing in 2 and 95 percent RH (relative humidity). Crack growth parameters measured in high humidity are systematically smaller (n and B) than those measured in low humidity, and crack velocities for dry environments are 100x lower than for wet environments. The crack velocity is very sensitive to small changes in RH at low RH. Biaxial and uniaxial stress states produced similar parameters. Confidence intervals on crack growth parameters that were estimated from propagation of errors solutions were comparable to those from Monte Carlo simulation. Use of scratch-like and indentation flaws produced similar crack growth parameters when residual stresses were considered.

  7. Effect of sputtering power on structure, adhesion strength and corrosion resistance of nitrogen doped diamond-like carbon thin films.

    PubMed

    Khun, N W; Liu, E

    2011-06-01

    Nitrogen doped diamond-like carbon (DLC:N) thin films were deposited on highly conductive p-Si substrates using a DC magnetron sputtering deposition system. The DLC:N films were characterized using X-ray photoelectron spectroscopy (XPS), micro-Raman spectroscopy, atomic force microscopy (AFM), contact angle measurement and micro-scratch test. The XPS and Raman results indicated that the sputtering power significantly influenced the properties of the films in terms of bonding configuration in the films. The corrosion performance of the DLC:N films was investigated in a 0.6 M NaCl solution by means of potentiodynamic polarization testing. It was found that the corrosion performance of the films could be enhanced by higher sputtering powers.

  8. Study of borehole probing methods to improve the ground characterization

    NASA Astrophysics Data System (ADS)

    Naeimipour, Ali

    Collecting geological information allows for optimizing ground control measures in underground structures. This includes understanding of the joints and discontinuities and rock strength to develop rock mass classifications. An ideal approach to collect such information is through correlating the drilling data from the roofbolters to assess rock strength and void location and properties. The current instrumented roofbolters are capable of providing some information on these properties but not fully developed for accurate ground characterization. To enhance existing systems additional instrumentation and testing was conducted in laboratory and field conditions. However, to define the geology along the boreholes, the use of probing was deemed to be most efficient approach for locating joints and structures in the ground and evaluation of rock strength. Therefore, this research focuses on selection and evaluation of proper borehole probes that can offer a reliable assessment of rock mass structure and rock strength. In particular, attention was paid to borehole televiewer to characterize rock mass structures and joints and development of mechanical rock scratcher for determination of rock strength. Rock bolt boreholes are commonly drilled in the ribs and the roof of underground environments. They are often small (about 1.5 inches) and short (mostly 2-3 meter). Most of them are oriented upward and thus, mostly dry or perhaps wet but not filled with water. No suitable system is available for probing in such conditions to identify the voids/joints and specifically to measure rock strength for evaluation of rock mass and related optimization of ground support design. A preliminary scan of available borehole probes proved that the best options for evaluation of rock structure is through analysis of borehole images, captured by optical televiewers. Laboratory and field trials with showed that these systems can be used to facilitate measurement of the location, frequency and partially condition of discontinuities. Two of the more promising tools have been tested during this project, which are QL40OBI Optical TV and Slim Borehole Scanner (SBS) manufacture by ALT-Mount Sopris and DMT, respectively. The field experiment with QL40OBI showed that the images generated for downward and sub-horizontal boreholes are of good quality and can be used to evaluate the joint conditions. However, this device is not suitable for use inside the upward drillholes. The Slim Borehole Scanner (SBS) manufactured by DMT in Germany has the required features for borescoping the roofbolt holes. This includes the ease of operation and suitable geometry along with an unwrapped 360-degree picture of the borehole wall. This instrument was concluded to be the best option yet for obtaining images from boreholes with any arbitrary orientation. In addition, a new tool, called Rock Strength Borehole Probe (RSBP), was developed for estimation of the rock strength through scratching the rock surface in the borehole. This device is designed to be a light, flexible, quick, non-disruptive, and cost effective alternative to estimate the rock strength inside the boreholes in underground mines and tunnels. An extensive number of laboratory tests under variable conditions were conducted to develop equations to estimate the Uniaxial Compressive Strength (UCS) and Brazilian Tensile Strength (BTS) of the rock from measured cutting forces. In these experiments, 27 different rock types were tested by full scale scratch tests, including the cutting tests by a miniature disc. The results show a good correlation between the normal force and the compressive strength of sedimentary/metamorphic rock if the depth of scratch is known. No significant correlation was observed for igneous rocks, due to the impacts of grain size. Current studies show promising results for using RSBP. The laboratory and field tests proved the functionality of this tool. This probe is capable of entering boreholes of 45 mm (1¾ in) diameter in any direction and create a groove on the walls and by measurement of the location and cutting forces, estimate rock strength. Additional testing in various underground operations are needed for fine tune the operational features of this probe and make it more accurate. The combination of rock strength and joint conditions will allow for development of rock mass classification that could be used for 3D imaging of the ground conditions around an underground opening as well as hazard maps for the roof.

  9. Avionics and Power Management for Low-Cost High-Altitude Balloon Science Platforms

    NASA Technical Reports Server (NTRS)

    Chin, Jeffrey; Roberts, Anthony; McNatt, Jeremiah

    2016-01-01

    High-altitude balloons (HABs) have become popular as educational and scientific platforms for planetary research. This document outlines key components for missions where low cost and rapid development are desired. As an alternative to ground-based vacuum and thermal testing, these systems can be flight tested at comparable costs. Communication, solar, space, and atmospheric sensing experiments often require environments where ground level testing can be challenging or impossible in certain cases. When performing HAB research the ability to monitor the status of the platform and gather data is key for both scientific and recoverability aspects of the mission. A few turnkey platform solutions are outlined that leverage rapidly evolving open-source engineering ecosystems. Rather than building custom components from scratch, these recommendations attempt to maximize simplicity and cost of HAB platforms to make launches more accessible to everyone.

  10. Effect of working pressure on corrosion behavior of nitrogen doped diamond-like carbon thin films deposited by DC magnetron sputtering.

    PubMed

    Khun, N W; Liu, E

    2011-06-01

    Nitrogen doped diamond-like carbon thin films were deposited on highly conductive p-silicon(100) substrates using a DC magnetron sputtering deposition system by varying working pressure in the deposition chamber. The bonding structure, adhesion strength, surface roughness and corrosion behavior of the films were investigated by using X-ray photoelectron spectroscopy, micro-Raman spectroscopy, micro-scratch test, atomic force microscopy and potentiodynamic polarization test. A 0.6 M NaCl electrolytic solution was used for the corrosion tests. The optimum corrosion resistance of the films was found at a working pressure of 7 mTorr at which a good balance between the kinetics of the sputtered ions and the surface mobility of the adatoms promoted a microstructure of the films with fewer porosities.

  11. Six fatal cases of classical rabies virus without biting incidents, Iran 1990-2010.

    PubMed

    Simani, Susan; Fayaz, Ahmad; Rahimi, Pooneh; Eslami, Naser; Howeizi, Nader; Biglari, Peyvand

    2012-07-01

    Rabies is an endemic fatal zoonotic disease, commonly transmitted to humans through contact (bites and scratches) with infected animals. During the years 1990-2010, six patients with the clinical symptoms of rabies (fever, tinnitus, buzzing, delirium and hydrophobia), with no history of a bite, were diagnosed by physicians in Iran. To obtain laboratory confirmation of rabies infection, different clinical specimens from each patient were sent to the World Health Organisation (WHO) Collaborating Center for Reference and Research on Rabies, Pasteur Institute of Iran. The first case was a 39-year-old male veterinary technician who entered his uncovered scratched hand into the mouth of a rabid bovine and became infected. Two years later, a herd of sheep being tended by a shepherd and his two sons were attacked by a rabid wolf. All three individuals were infected when they applied burnt thorny wool to the sheep's wounds as a bandage. Their hands were scratched and then infected through contact with the remaining saliva of the rabid wolf on the sheep's wounds. In 1994, two other human cases occurred through corneal transplantation from the same donor who had died with the clinical signs of food poisoning (according to his hospital record), which probably was a misdiagnosis of rabies infection. This is a case series study that describes human rabies cases without biting incidents. According to the WHO recommendation, human rabies cases are notifiable, therefore, in Iran, a rabies surveillance system has been established to follow these cases. During the last decade, six patients with no 'history of a bite' were hospitalised with growing symptoms of rabies. The data were collected from each patient by the physicians and transferred to the Ministry of Health and Medical Education of Iran, and to the WHO Collaborating Center for Reference and Research on Rabies, Pasteur Institute of Iran as the only testing laboratory. Thus, they came to the attention of the surveillance system. Ante-mortem diagnosis was performed on saliva, cerebrospinal fluid and blood samples that were collected from the first patient by the physicians. Fresh brain specimens from all patients were kept in a mixture of 50% glycerol in phosphate-buffered saline and transported on ice to the WHO Collaborating Center for Reference and Research on Rabies. For the first patient, rabies virus was investigated in saliva using the rapid tissue cell inoculation test (RTCIT) and the mouse inoculation test (MIT). Anti-rabies antibodies in this patient's serum and cerebrospinal fluid (CSF) were examined using the mouse neutralisation test (MNT). Fresh brain specimens from all patients were examined using the fluorescence antibody test (FAT) as recommended by the WHO laboratory manual in rabies as the post-mortem diagnostic test for rabies. Rabies infection was confirmed in all of the deceased patients. Anti-rabies antibodies were identified only in one patient's serum specimen. Testing also showed that the rabies virus isolated was the classic rabies virus (serotype 1), which is widespread in Iran. Prevention and control of this fatal disease require a sensitive surveillance system to follow 'suspected' animal and human rabies cases thoroughly through the improved reporting system, which contains the history of exposure, clinical examinations, symptoms and laboratory results. This study describes some notable human rabies infections and their transmission modes to prevent occupational accidents. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. [Application of Warthin-Starry stain, immunohistochemistry and transmission electron microscopy in diagnosis of cat scratch disease].

    PubMed

    Huang, Juan; Dai, Lin; Lei, Song; Liao, Dian-ying; Wang, Xiao-qing; Luo, Tian-you; Chen, Yu; Hang, Zhen-biao; Li, Gan-di; Dong, Dan-dan; Xu, Gang; Gu, Zheng-ce; Hao, Ji-ling; Hua, Ping; He, Lei; Duan, Fang-lei

    2010-04-01

    To evaluate the diagnostic utility of Warthin-Starry silver stain, immunohistochemistry and transmission electron microscopy in the detection of human Bartonella henselae infection and pathologic diagnosis of cat scratch disease (CSD). The paraffin-embedded lymph node tissues of 77 histologically-defined cases of cat scratch disease collected during the period from January, 1998 to December, 2008 were retrieved and studied using Warthin-Starry silver stain (WS stain) and mouse monoclonal antibody against Bartonella henselae (BhmAB stain). Five cases rich in bacteria were selected for transmission electron microscopy. Under electron microscope, the organisms Bartonella henselae appeared polymorphic, round, elliptical, short rod or bacilliform shapes, ranged from 0.489 to 1.110 microm by 0.333 to 0.534 microm and often clustered together. Black short rod-shaped bacilli arranged in chains or clumps were demonstrated in 61.0% (47/77) of CSD by WS stain. The organisms were located outside the cells and lie mainly in the necrotic debris, especially near the nodal capsule. In 72.7% (56/77) of the cases, dot-like, granular as well as few linear positive signals were observed using BhmAB immunostain and showed similar localization. Positive results for both stains were identified in 59.7% (46/77) of the cases. When applying both stains together, Bartonella henselae was observed in 74.0% (57/77) of the case. The difference between the results obtained by WS stain and BhmAB immunostain was of statistical significance (P < 0.05). Bartonella henselae is the causative pathogen of cat scratch disease. WS stain, BhmAB immunostain and transmission electron microscopy are helpful in confirming the histologic diagnosis. Immunostaining using BhmAB can be a better alternative than WS stain in demonstrating the organisms.

  13. Determination of the wound healing effect of Calendula extracts using the scratch assay with 3T3 fibroblasts.

    PubMed

    Fronza, M; Heinzmann, B; Hamburger, M; Laufer, S; Merfort, I

    2009-12-10

    PHARMACOLOGICAL RELEVANCE: Presentation of the scratch assay as a convenient and inexpensive in vitro tool to gain first insights in the wound healing potential of plant extracts and natural compounds. The present study deals with the optimization of the scratch assay which can be used as an in vitro model for quantification of fibroblast migration to and proliferation into the wounded area. It is suitable for the first evaluation of the wound re-epithelialization potential of crude herbal extracts, isolated compounds and pharmaceutical preparations. As a proof of concept three preparations from traditional medicinal plants were investigated. Swiss 3T3 albino mouse fibroblasts were used in monolayers and platelet derived growth factor as positive control. Hexane and ethanolic extracts from Calendula officinalis and Matricaria recutita, Hypericum oil as well as the triterpenoids faradiol myristate and palmitate were studied. To differentiate between proliferation and migration antimitotic mitomycin C was added. Both extracts of Calendula officinalis stimulated proliferation and migration of fibroblasts at low concentrations, e.g. 10 microg/ml enhanced cell numbers by 64.35% and 70.53%, respectively. Inhibition of proliferation showed that this effect is mainly due to stimulation of migration. Faradiol myristate and palmitate gave comparable stimulation rates at an almost 50 microg/ml concentration, indicating that they contribute partially, but not most significantly to the wound healing effects of Calendula preparations. Extracts from Matricaria recutita were only moderately active. Hypericum oil was cytotoxic at concentrations higher than 0.5 microg/ml. The scratch assay in the present form can be used as a promising scientific approach and platform to differentiate between plant extracts known for their wound healing and their anti-inflammatory properties.

  14. Brain Processing of Contagious Itch in Patients with Atopic Dermatitis

    PubMed Central

    Schut, Christina; Mochizuki, Hideki; Grossman, Shoshana K.; Lin, Andrew C.; Conklin, Christopher J.; Mohamed, Feroze B.; Gieler, Uwe; Kupfer, Joerg; Yosipovitch, Gil

    2017-01-01

    Several studies show that itch and scratching cannot only be induced by pruritogens like histamine or cowhage, but also by the presentation of certain (audio-) visual stimuli like pictures on crawling insects or videos showing other people scratching. This phenomenon is coined “Contagious itch” (CI). Due to the fact that CI is more profound in patients with the chronic itchy skin disease atopic dermatitis (AD), we believe that it is highly relevant to study brain processing of CI in this group. Knowledge on brain areas involved in CI in AD-patients can provide us with useful hints regarding non-invasive treatments that AD-patients could profit from when they are confronted with itch-inducing situations in daily life. Therefore, this study investigated the brain processing of CI in AD-patients. 11 AD-patients underwent fMRI scans during the presentation of an itch inducing experimental video (EV) and a non-itch inducing control video (CV). Perfusion based brain activity was measured using arterial spin labeling functional MRI. As expected, the EV compared to the CV led to an increase in itch and scratching (p < 0.05). CI led to a significant increase in brain activity in the supplementary motor area, left ventral striatum and right orbitofrontal cortex (threshold: p < 0.001; cluster size k > 50). Moreover, itch induced by watching the EV was by trend correlated with activity in memory-related regions including the temporal cortex and the (pre-) cuneus as well as the posterior operculum, a brain region involved in itch processing (threshold: p < 0.005; cluster size k > 50). These findings suggest that the fronto-striatal circuit, which is associated with the desire to scratch, might be a target region for non-invasive treatments in AD patients. PMID:28790959

  15. Ameliorating effect of Yokukansan on the development of atopic dermatitis-like lesions and scratching behavior in socially isolated NC/Nga mice.

    PubMed

    Funakushi, Naoko; Yamaguchi, Takuji; Jiang, Ju; Imamura, Sachiko; Kuhara, Takatoshi; Suto, Hajime; Ueki, Rie; Kase, Yoshio; Kobayashi, Hiroyuki; Ogawa, Hideoki; Ikeda, Shigaku

    2011-11-01

    Yokukansan (YKS) has been used in Japan as a remedy for neurosis, insomnia, and children with night crying. In a previous study, we reported that YKS controls scratching behavior and inhibits the development of atopic dermatitis (AD)-like lesions in NC/Nga mice. In this study, we investigated the effects of YKS on the development of AD-like lesions in socially isolated NC/Nga mice compared with the effects of fexofenadine and elucidated the mechanism of the ameliorating effect of YKS on the skin lesions. Ten-week-old male NC/Nga mice were divided into three groups (n = 5/group): the conventional control, the YKS-treated, and the fexofenadine-treated groups, and were kept isolated under conventional conditions for 6 weeks. Measurements were made of dermatitis scores and transepidermal water loss (TEWL), scratching and grooming behaviors. Immunohistochemistry and mRNA levels were also evaluated. We performed similar experiments under specific pathogen free (SPF) conditions that served as a SPF control. YKS and fexofenadine inhibited the aggravation of skin lesions and decreased TEWL, but only YKS decreased the numbers of scratching and pathologic grooming behaviors. Immunohistochemistry and RT-PCR revealed that N-methyl-D: -aspartate (NMDA) receptor expression was increased in the skin of conventional control mice and was decreased in YKS-treated mice. Glutamate transporter-1 (GLT-1) mRNA levels were decreased in the skin of conventional control mice and were increased in YKS-treated mice. The results indicate that YKS ameliorates AD-like skin lesions in NC/Nga mice through a mechanism distinct from that of fexofenadine. Furthermore, the effects of YKS are suggested to be mediated via glutamate signaling in the skin lesions.

  16. Impaired Wound Healing in Hypoxic Renal Tubular Cells: Roles of Hypoxia-Inducible Factor-1 and Glycogen Synthase Kinase 3β/β-Catenin Signaling

    PubMed Central

    Peng, Jianping; Ramesh, Ganesan; Sun, Lin

    2012-01-01

    Wound and subsequent healing are frequently associated with hypoxia. Although hypoxia induces angiogenesis for tissue remodeling during wound healing, it may also affect the healing response of parenchymal cells. Whether and how wound healing is affected by hypoxia in kidney cells and tissues is currently unknown. Here, we used scratch-wound healing and transwell migration models to examine the effect of hypoxia in cultured renal proximal tubular cells (RPTC). Wound healing and migration were significantly slower in hypoxic (1% oxygen) RPTC than normoxic (21% oxygen) cells. Hypoxia-inducible factor-1α (HIF-1α) was induced during scratch-wound healing in normoxia, and the induction was more evident in hypoxia. Nevertheless, HIF-1α-null and wild-type cells healed similarly after scratch wounding. Moreover, activation of HIF-1α with dimethyloxalylglycine in normoxic cells did not suppress wound healing, negating a major role of HIF-1α in wound healing in this model. Scratch-wound healing was also associated with glycogen synthase kinase 3β (GSK3β)/β-catenin signaling, which was further enhanced by hypoxia. Pharmacological inhibition of GSK3β resulted in β-catenin expression, accompanied by the suppression of wound healing and transwell cell migration. Ectopic expression of β-catenin in normoxic cells could also suppress wound healing, mimicking the effect of hypoxia. Conversely, inhibition of β-catenin via dominant negative mutants or short hairpin RNA improved wound healing and transwell migration in hypoxic cells. The results suggest that GSK3β/β-catenin signaling may contribute to defective wound healing in hypoxic renal cells and tissues. PMID:22010210

  17. Supraspinal actions of nociceptin/orphanin FQ, morphine and substance P in regulating pain and itch in non-human primates

    PubMed Central

    Ding, H; Hayashida, K; Suto, T; Sukhtankar, D D; Kimura, M; Mendenhall, V; Ko, M C

    2015-01-01

    Background and Purpose Nociceptin/orphanin FQ (N/OFQ) peptide (NOP) receptor agonists display a promising analgesic profile in preclinical studies. However, supraspinal N/OFQ produced hyperalgesia in rodents and such effects have not been addressed in primates. Thus, the aim of this study was to investigate the effects of centrally administered ligands on regulating pain and itch in non-human primates. In particular, nociceptive thresholds affected by intracisternal N/OFQ were compared with those of morphine and substance P, known to provide analgesia and mediate hyperalgesia, respectively, in humans. Experimental Approach Intrathecal catheters were installed to allow intracisternal and lumbar intrathecal administration in awake and unanaesthetized rhesus monkeys. Nociceptive responses were measured using the warm water tail-withdrawal assay. Itch scratching responses were scored from videotapes recording behavioural activities of monkeys in their home cages. Antagonist studies were conducted to validate the receptor mechanisms underlying intracisternally elicited behavioural responses. Key Results Intracisternal morphine (100 nmol) elicited more head scratches than those after intrathecal morphine. Distinct dermatomal scratching locations between the two routes suggest a corresponding activation of supraspinal and spinal μ receptors. Unlike intracisternal substance P, which induced hyperalgesia, intracisternal N/OFQ (100 nmol) produced antinociceptive effects mediated by NOP receptors. Neither peptide increased scratching responses. Conclusions and Implications Taken together, these results demonstrated differential actions of ligands in the primate supraspinal region in regulating pain and itch. This study not only improves scientific understanding of the N/OFQ-NOP receptor system in pain processing but also supports the therapeutic potential of NOP-related ligands as analgesics. PMID:25752320

  18. Comparison of In-Vitro and Ex-Vivo Wound Healing Assays for the Investigation of Diabetic Wound Healing and Demonstration of a Beneficial Effect of a Triterpene Extract

    PubMed Central

    Ueck, Christopher; Volksdorf, Thomas; Houdek, Pia; Vidal-y-Sy, Sabine; Sehner, Susanne; Ellinger, Bernhard; Lobmann, Ralf; Larena-Avellaneda, Axel; Reinshagen, Konrad; Ridderbusch, Ina; Kohrmeyer, Klaas; Moll, Ingrid; Daniels, Rolf; Werner, Philipp; Merfort, Irmgard; Brandner, Johanna M.

    2017-01-01

    Diabetes mellitus is a frequent cause for chronic, difficult-to-treat wounds. New therapies for diabetic wounds are urgently needed and in-vitro or ex-vivo test systems are essential for the initial identification of new active molecules. The aim of this study is to compare in-vitro and ex-vivo test systems for their usability for early drug screening and to investigate the efficacy of a birch bark triterpene extract (TE) that has been proven ex-vivo and clinically to accelerate non-diabetic wound healing (WH), in a diabetic context. We investigated in-vitro models for diabetic WH, i.e. scratch assays with human keratinocytes from diabetic donors or cultured under hyperglycaemic conditions and a newly developed porcine ex-vivo hyperglycaemic WH model for their potential to mimic delayed diabetic WH and for the influence of TE in these test systems. We show that keratinocytes from diabetic donors often fail to exhibit significantly delayed WH. For cells under hyperglycaemic conditions significant decrease is observed but is influenced by choice of medium and presence of supplements. Also, donor age plays a role. Interestingly, hyperglycaemic effects are mainly hyperosmolaric effects in scratch assays. Ex-vivo models under hyperglycaemic conditions show a clear and substantial decrease of WH, and here both glucose and hyperosmolarity effects are involved. Finally, we provide evidence that TE is also beneficial for ex-vivo hyperglycaemic WH, resulting in significantly increased length of regenerated epidermis to 188±16% and 183±11% (SEM; p<0.05) compared to controls when using two different TE formulations. In conclusion, our results suggest that microenvironmental influences are important in WH test systems and that therefore the more complex hyperglycaemic ex-vivo model is more suitable for early drug screening. Limitations of the in-vitro and ex-vivo models are discussed. Furthermore our data recommend TE as a promising candidate for in-vivo testings in diabetic wounds. PMID:28046026

  19. An analysis of suppressing migratory effect on human urinary bladder cancer cell line by silencing of snail-1.

    PubMed

    Salehi, Shima; Mansoori, Behzad; Mohammadi, Ali; Davoudian, Sadaf; Musavi Shenas, Seyed Mohammad Hossein; Shajari, Neda; Majidi, Jafar; Baradaran, Behzad

    2017-12-01

    Snail-1 actively participates in tumor progression, invasion, and migration. Targeting snail-1 expression can suppress the EMT process in cancer. The aim of this study was to investigate the effect of snail1 silencing on urinary bladder cancer. Quantitative RT-PCR was used to detect snail-1 and other related metastatic genes expression following siRNA knockdown in urinary bladder cancer EJ-138 cells. The protein level of snail1 was assessed by Western blot. MTT and TUNEL assays were assessed to understand if snail-1 had survival effects on EJ-138 cells. Scratch wound healing assay measured cell motility effects after snail1 suppression. The significant silencing of snail-1 reached 60pmol siRNA in a 48-h post-transfection. The result of scratch assay showed that snail-1 silencing significantly decreased Vimentin, MMPs, and CXCR4 expression; however, expression of E-cadherin was induced. The cell death assay indicated that snail-1 played the crucial role in bladder cancer survival rate. These results propose that snail-1 plays a major role in the progression and migration of urinary bladder cancer, and can be a potential therapeutic target for target therapy of invasive urinary bladder cancer. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  20. Nanofabrication on monocrystalline silicon through friction-induced selective etching of Si3N4 mask

    PubMed Central

    2014-01-01

    A new fabrication method is proposed to produce nanostructures on monocrystalline silicon based on the friction-induced selective etching of its Si3N4 mask. With low-pressure chemical vapor deposition (LPCVD) Si3N4 film as etching mask on Si(100) surface, the fabrication can be realized by nanoscratching on the Si3N4 mask and post-etching in hydrofluoric acid (HF) and potassium hydroxide (KOH) solution in sequence. Scanning Auger nanoprobe analysis indicated that the HF solution could selectively etch the scratched Si3N4 mask and then provide the gap for post-etching of silicon substrate in KOH solution. Experimental results suggested that the fabrication depth increased with the increase of the scratching load or KOH etching period. Because of the excellent masking ability of the Si3N4 film, the maximum fabrication depth of nanostructure on silicon can reach several microns. Compared to the traditional friction-induced selective etching technique, the present method can fabricate structures with lesser damage and deeper depths. Since the proposed method has been demonstrated to be a less destructive and flexible way to fabricate a large-area texture structure, it will provide new opportunities for Si-based nanofabrication. PMID:24940174

  1. Cat-Scratch Disease: A Pitfall for Lymphoma Evaluation by FDG-PET/CT.

    PubMed

    Dubreuil, Julien; Dony, Arthur; Salles, Gilles; Traverse-Glehen, Alexandra; Giammarile, Francesco; Skanjeti, Andrea

    2017-02-01

    FDG-PET/CT is a standard of care in staging and response assessment of Hodgkin lymphoma. Hence, it is important to recognize pitfalls owing to the potential therapeutic impact. We report a case of a 29-year-old woman affected by stage III bulky Hodgkin lymphoma. The interim FDG-PET/CT showed a complete metabolic response. After three new cycles of chemotherapy, the patient showed fever and lymphadenopathy at clinic examination, PET/CT revealed several FDG uptakes at lymph nodes in inguinal and iliac region. Pathologic analyses, after biopsy and serologic examinations, led to the diagnosis of cat-scratch disease.

  2. Improvement of Scratch and Wear Resistance of Polymers by Fillers Including Nanofillers

    PubMed Central

    Brostow, Witold; Lobland, Haley E. Hagg; Hnatchuk, Nathalie; Perez, Jose M.

    2017-01-01

    Polymers have lower resistance to scratching and wear than metals. Liquid lubricants work well for metals but not for polymers nor for polymer-based composites (PBCs). We review approaches for improvement of tribological properties of polymers based on inclusion of fillers. The fillers can be metallic or ceramic—with obvious consequences for electrical resistivity of the composites. Distinctions between effectiveness of micro- versus nano-particles are analyzed. For example, aluminum nanoparticles as filler are more effective for property improvement than microparticles at the same overall volumetric concentration. Prevention of local agglomeration of filler particles is discussed along with a technique to verify the prevention. PMID:28336900

  3. Scratch-Resistant Lenses

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Lewis Research Center developed a process for achieving diamond- hard coatings for aerospace systems. The technique involves coating the material with a film of diamond-like carbon (DLC) using direct ion deposition. An ion generator creates a stream of ions from a hydrocarbon gas source; the carbon ions impinge directly on the target substrate and 'grow' into a thin DLC film. In 1988, Air Products and Chemicals, Inc. received a license to the NASA patent. Diamonex, an Air Products spinoff company, further developed the NASA process to create the DiamondHard technology used on the Bausch & Lomb Ray- Ban Survivors sunglasses. The sunglasses are scratch-resistant and shed water more easily, thus reducing spotting.

  4. [Pediatric pneumonia, pleural effusion, and pericarditis following cat scratch disease and serological cross-reactions among Bartonella henselae and Rickettsia japonica determined by indirect fluorescence antibodies].

    PubMed

    Takeda, Nobue; Ishiwada, Naruhiko; Fukasawa, Chie; Furuya, Yumiko; Tsuneoka, Hidehiro; Tsukahara, Masato; Kohno, Yoichi

    2007-03-01

    Cat scratch disease is associated with a variety of systemic manifestations. We report a pediatric case associated with pneumonia, pleural effusion, and pericarditis. A 3-year-old boy developed prolonged fever unresponsive to antibiotic treatment, including azithromycin and minocycline. Although the fever resolved with corticosteroid treatment, Bartonella henselae IgG titer was positive in indirect fluorescence antibodies, as was Rickettsia japonica IgG titer. Both titers were significantly reduced by serum absorption with B. henselae antigens, and we observed a serological cross-reaction between B. henselae and R. japonica.

  5. Subnanosecond-laser-induced periodic surface structures on prescratched silicon substrate

    NASA Astrophysics Data System (ADS)

    Hongo, Motoharu; Matsuo, Shigeki

    2016-06-01

    Laser-induced periodic surface structures (LIPSS) were fabricated on a prescratched silicon surface by irradiation with subnanosecond laser pulses. Low-spatial-frequency LIPSS (LSFL) were observed in the central and peripheral regions; both had a period Λ close to the laser wavelength λ, and the wavevector orientation was parallel to the electric field of the laser beam. The LSFL in the peripheral region seemed to be growing, that is, expanding in length with increasing number of pulses, into the outer regions. In addition, high-spatial-frequency LIPSS, Λ ≲ λ /2, were found along the scratches, and their wavevector orientation was parallel to the scratches.

  6. Monoatomic layer removal mechanism in chemical mechanical polishing process: A molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Si, Lina; Guo, Dan; Luo, Jianbin; Lu, Xinchun

    2010-03-01

    Molecular dynamics simulations of nanoscratching processes were used to study the atomic-scale removal mechanism of single crystalline silicon in chemical mechanical polishing (CMP) process and particular attention was paid to the effect of scratching depth. The simulation results under a scratching depth of 1 nm showed that a thick layer of silicon material was removed by chip formation and an amorphous layer was formed on the silicon surface after nanoscratching. By contrast, the simulation results with a depth of 0.1 nm indicated that just one monoatomic layer of workpiece was removed and a well ordered crystalline surface was obtained, which is quite consistent with previous CMP experimental results. Therefore, monoatomic layer removal mechanism was presented, by which it is considered that during CMP process the material was removed by one monoatomic layer after another, and the mechanism could provide a reasonable understanding on how the high precision surface was obtained. Also, the effects of the silica particle size and scratching velocity on the removal mechanism were investigated; the wear regimes and interatomic forces between silica particle and workpiece were studied to account for the different removal mechanisms with indentation depths of 0.1 and 1 nm.

  7. Sporotrichoid Mycobacterium marinum infection of the face following a cat scratch.

    PubMed

    Phan, Tai Anh; Relic, John

    2010-02-01

    Mycobacterium marinum infections in humans uncommonly affect the face and are not known to be associated with cat scratches. We describe a 24-year-old woman who presented with a 3-month history of multiple tender, occasionally discharging cystic nodules involving the left side of her face in a sporotrichoid distribution. She had suffered a cat scratch to her left lower eyelid 3 weeks before the onset of the eruption and owned multiple tropical fish tanks. She was systemically well and had no lymphadenopathy. She had a background history of a 4.5-mm-thick nodular melanoma of her temple treated by wide local excision and negative sentinel lymph node biopsy 4 years prior. Skin biopsies showed multiple variably sized granulomas surrounded by thick cuffs of lymphocytes involving the superficial and deep dermis with no organisms seen on Ziehl-Neelsen, peroidic acid-Schiff and methenamine silver stains. Laboratory investigations showed a mildly raised erythrocyte sedimentation rate but normal full blood count and C-reactive protein. Fluid from the left cheek grew an acid-fast bacillus identified as Mycobacterium marinum. The skin eruption cleared after 5-month treatment with oral clarithromycin 500 mg twice daily and rifampicin 600 mg daily.

  8. Nanomechanical Behavior of High Gas Barrier Multilayer Thin Films.

    PubMed

    Humood, Mohammad; Chowdhury, Shahla; Song, Yixuan; Tzeng, Ping; Grunlan, Jaime C; Polycarpou, Andreas A

    2016-05-04

    Nanoindentation and nanoscratch experiments were performed on thin multilayer films manufactured using the layer-by-layer (LbL) assembly technique. These films are known to exhibit high gas barrier, but little is known about their durability, which is an important feature for various packaging applications (e.g., food and electronics). Films were prepared from bilayer and quadlayer sequences, with varying thickness and composition. In an effort to evaluate multilayer thin film surface and mechanical properties, and their resistance to failure and wear, a comprehensive range of experiments were conducted: low and high load indentation, low and high load scratch. Some of the thin films were found to have exceptional mechanical behavior and exhibit excellent scratch resistance. Specifically, nanobrick wall structures, comprising montmorillonite (MMT) clay and polyethylenimine (PEI) bilayers, are the most durable coatings. PEI/MMT films exhibit high hardness, large elastic modulus, high elastic recovery, low friction, low scratch depth, and a smooth surface. When combined with the low oxygen permeability and high optical transmission of these thin films, these excellent mechanical properties make them good candidates for hard coating surface-sensitive substrates, where polymers are required to sustain long-term surface aesthetics and quality.

  9. Optimization of chemical vapor deposition diamond films growth on steel: correlation between mechanical properties, structure, and composition.

    PubMed

    Laikhtman, A; Rapoport, L; Perfilyev, V; Moshkovich, A; Akhvlediani, R; Hoffman, A

    2011-09-01

    In the present work we perform optimization of mechanical and crystalline properties of CVD microcrystalline diamond films grown on steel substrates. A chromium-nitride (Cr-N) interlayer had been previously proposed to serve as a buffer for carbon and iron inter-diffusion and as a matching layer for the widely differing expansion coefficients of diamond and steel. However, adhesion and wear as well as crystalline perfection of diamond films are strongly affected by conditions of both Cr-N interlayer preparation and CVD diamond deposition. In this work we assess the effects of two parameters. The first one is the temperature of the Cr-N interlayer preparation: temperatures in the range of 500 degrees C-800 degrees C were used. The second one is diamond film thickness in the 0.5 microm-2 microm range monitored through variation of the deposition time from approximately 30 min to 2 hours. The mechanical properties of so deposited diamond films were investigated. For this purpose, scratch tests were performed at different indentation loads. The friction coefficient and wear loss were assessed. The mechanical and tribological properties were related to structure, composition, and crystalline perfection of diamond films which were extensively analyzed using different microscopic and spectroscopic techniques. It was found that relatively thick diamond film deposited on the Cr-N interlayer prepared at the temperature similar to that of the CVD process has the best mechanical and adhesion strength. This film was stable without visible cracks around the wear track during all scratch tests with different indentation loads. In other cases, cracking and delamination of the films took place at low to moderate indentation loads.

  10. Sesamin induces ER stress-mediated apoptosis and activates autophagy in cervical cancer cells.

    PubMed

    Dou, Haowen; Yang, Shasha; Hu, Yulai; Xu, Dongyuan; Liu, Lan; Li, Xiangdan

    2018-05-01

    Sesamin, a major lignan of sesame oil, has demonstrated anticancer properties. However, its anticancer effects on cervical cancer have not been studied. Here, we investigated the effects of sesamin on cervical cancer (HeLa) cell line and explored the underlying mechanisms. HeLa cells were cultured with sesamin. CCK-8 and scratch wound test were applied to detect the proliferation and migration ability, while flow cytometry and TUNEL staining were applied to detect apoptosis. The expression of Bax and Bcl-2 was assessed by Western blotting. Further observe the ultrastructure using transmission electron microscopy (TEM) and detect the expression of caspase-12, GRP78, GADD153, IRE1α, p-IRE1α, JNK, p-JNK, LC3I/II and beclin-1. In addition, HeLa cells were treated with 3-MA (an autophagy inhibitor) and/or sesamin. Then detect the expression of LC3I/II and cell viability. CCK-8 and scratch wound test revealed that sesamin inhibits HeLa cells proliferation and migration, while flow cytometry and TUNEL staining indicated that sesamin induces apoptosis in these cells. In sesamin group, the expression of Bax, caspase-12, GRP78, GADD153, p-IRE1α, p-JNK, LC3I/II and beclin-1 was up-regulated while Bcl-2 was down-regulated compared to control group. Further research revealed that sesamin also induces Hela cells autophagy and inhibition of autophagy increases cell viability of sesamin-treated HeLa cells. Sesamin inhibits proliferation/migration of HeLa cells and induces ER stress-mediated apoptosis through IRE1α/JNK pathway, and that it activates autophagy and autophagic death in these cells, further validate the anticancer effect of sesamin. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Cat-scratch disease presenting as multiple hepatic lesions: case report and literature review.

    PubMed

    Baptista, Mariana Andrade; Lo, Denise Swei; Hein, Noely; Hirose, Maki; Yoshioka, Cristina Ryoka Miyao; Ragazzi, Selma Lopes Betta; Gilio, Alfredo Elias; Ferronato, Angela Esposito

    2014-01-01

    Although infectious diseases are the most prevalent cause of fevers of unknown origin (FUO), this diagnosis remains challenging in some pediatric patients. Imaging exams, such as computed tomography (CT) are frequently required during the diagnostic processes. The presence of multiple hypoattenuating scattered images throughout the liver associated with the history of cohabitation with cats should raise the suspicion of the diagnosis of cat-scratch disease (CSD), although the main etiologic agent of liver abscesses in childhood is S taphylococcus aureus . Differential diagnosis by clinical and epidemiological data with Bartonella henselae is often advisable. The authors report the case of a boy aged 2 years and 9 months with 16-day history of daily fever accompanied by intermittent abdominal pain. Physical examination was unremarkable. Abdominal ultrasound performed in the initial work up was unrevealing, but an abdominal CT that was performed afterwards disclosed multiple hypoattenuating hepatic images compatible with the diagnosis of micro abscesses. Initial antibiotic regimen included cefotaxime, metronidazole, and oxacillin. Due to the epidemiology of close contact with kittens, diagnosis of CSD was considered and confirmed by serologic tests. Therefore, the initial antibiotics were replaced by clarithromycin orally for 14 days followed by fever defervescence and clinical improvement. The authors call attention to this uncommon diagnosis in a child presenting with FUO and multiple hepatic images suggestive of micro abscesses.

  12. Unique zinc mass in mandibles separates drywood termites from other groups of termites

    NASA Astrophysics Data System (ADS)

    Cribb, Bronwen W.; Stewart, Aaron; Huang, Han; Truss, Rowan; Noller, Barry; Rasch, Ronald; Zalucki, Myron P.

    2008-05-01

    Previously, the presence of metals in arthropod mandibles has been linked with harder cuticle, and in termites, a 20% increase in hardness has been found for mandibles containing major quantities of zinc. The current study utilises electron microscopy and energy-dispersive X-ray microanalysis to assess incidence and abundance of metals in all extant subfamilies of the Isoptera. The basal clades contain no zinc and little to no manganese in the cutting edge of the mandible cuticle, suggesting that these states are ancestral for termites. However, experimentation with mandibles in vitro indicates the presence of some elements of the cuticular biochemistry necessary to enable uptake of zinc. The Termopsidae, Serritermitidae, Rhinotermitidae and Termitidae all contain minor quantities of manganese, while trace to minor quantities of zinc occur in all except the Serritermitidae. In contrast, all Kalotermitidae or drywood termites contain major levels of zinc in the mandible edge. Diet and life type are explored as links to metal profiles across the termites. The presence of harder mandibles in the drywood termites may be related to lack of access to free water with which to moisten wood. Scratch tests were applied to a set of mandibles. The coefficient of friction for Cryptotermes primus (Kalotermitidae) mandibles, when compared with species from other subfamilies, indicates that zinc-containing mandibles are likely to be more scratch resistant.

  13. Occupational allergic rhinitis from guar gum.

    PubMed

    Kanerva, L; Tupasela, O; Jolanki, R; Vaheri, E; Estlander, T; Keskinen, H

    1988-05-01

    Three cases of allergic rhinitis from a vegetable gum, guar gum, have been detected. Two subjects were exposed to fine guar gum powder (Emco Gum 563, Meyhall Chemical AG, Switzerland), an insulator in rubber cables, when opening cables in a power cable laboratory. After 1-2 years' exposure the patients developed rhinitis. Scratch-chamber tests, nasal provocation tests, nasal eosinophilia and a RAST test proved their allergy. A third subject developed allergic rhinitis from another guar gum product (Meyproid 5306, Meyhall Chemical AG) after 2 years' exposure in a paper factory. A positive skin test and nasal provocation test confirmed the diagnosis. A fourth case of possible allergy to guar gum after exposure to Meyproid 5306 in a paper factory is also presented. No final diagnosis was reached in this case (in 1974). The present subjects, only one of whom was atopic, developed allergy within 2 years, although their exposure to guar gum was not especially heavy. Therefore, when handling guar, adequate ventilation facilities should be provided and protective clothing, including a respiratory mask, should be worn.

  14. Incentives and participation in a medical survey.

    PubMed

    Gjøstein, Dagrun Kyte; Huitfeldt, Anders; Løberg, Magnus; Adami, Hans-Olov; Garborg, Kjetil; Kalager, Mette; Bretthauer, Michael

    2016-07-01

    BACKGROUND Questionnaire surveys are important for surveying the health and disease behaviour of the population, but recent years have seen a fall in participation. Our study tested whether incentives can increase participation in these surveys.MATERIAL AND METHOD We sent a questionnaire on risk factors for colorectal cancer (height, weight, smoking, self-reported diagnoses, family medical history) to non-screened participants in a randomised colonoscopy screening study for colorectal cancer: participants who were invited but did not attend for colonoscopy examination (screening-invited) and persons who were not offered colonoscopy (control group). The persons were randomised to three groups: no financial incentive, lottery scratch cards included with the form, or a prize draw for a tablet computer when they responded to the form. We followed up all the incentive groups with telephone reminder calls, and before the prize draw for the tablet computer.RESULTS Altogether 3 705 of 6 795 persons (54.5  %) responded to the questionnaire; 43.5  % of those invited for screening and 65.6  % of the control group (p < 0.001). The proportion that answered was not influenced by incentives, either among those invited for screening (42.4  % in the non-prize group, 45.5  % in the lottery scratch card group and 42.6  % in the prize draw group; p = 0.24), or in the control group (65.6  % in the non-prize group, 66.4  % in the lottery scratch card group and 64.7  % in the prize draw group; p = 0.69). Prior to reminder calls, 39.2  % responded. A further 15.3  % responded following telephone reminder calls (14.1  % of the screening-invited and 16.5  % of the control group; p < 0.001).INTERPRETATION Incentives did not increase participation in this medical questionnaire survey. Use of telephone reminder calls and telephone interviews increased participation, but whether this is more effective than other methods requires further study.

  15. Development of Titanium Dioxide (TiO2 ) Nanocoatings on Food Contact Surfaces and Method to Evaluate Their Durability and Photocatalytic Bactericidal Property.

    PubMed

    Yemmireddy, Veerachandra K; Farrell, Glenn D; Hung, Yen-Con

    2015-08-01

    Titanium dioxide (TiO2 ) is a well-known photocatalyst for its excellent bactericidal property under UVA light. The purpose of this study was to develop physically stable TiO2 coatings on food contact surfaces using different binding agents and develop methods to evaluate their durability and microbicidal property. Several types of organic and inorganic binders such as polyvinyl alcohol, polyethylene glycol, polyurethane, polycrylic, sodium and potassium silicates, shellac resin, and other commercial binders were used at 1:1 to 1:16 nanoparticle to binder weight ratios to develop a formulation for TiO2 coating on stainless steel surfaces. Among the tested binders, polyurethane, polycrylic, and shellac resin were found to be physically more stable when used in TiO2 coating at 1:4 to 1:16 weight ratio. The physical stability of TiO2 coatings was determined using adhesion strength and scratch hardness tests by following standard ASTM procedures. Further, wear resistance of the coatings was evaluated based on a simulated cleaning procedure used in food processing environments. TiO2 coating with polyurethane at a 1:8 nanoparticle to binder weight ratio showed the highest scratch hardness (1.08 GPa) followed by coating with polycrylic (0.68 GPa) and shellac (0.14 GPa) binders. Three different techniques, namely direct spreading, glass cover-slip, and indented coupon were compared to determine the photocatalytic bactericidal property of TiO2 coatings against Escherichia coli 0157:H7 at 2 mW/cm(2) UVA light intensity. Under the tested conditions, the indented coupon technique was found to be the most appropriate method to determine the bactericidal property of TiO2 coatings and showed a reduction of 3.5 log CFU/cm(2) in 2 h. © 2015 Institute of Food Technologists®

  16. Volatile oils of Chinese crude medicines exhibit antiparasitic activity against human Demodex with no adverse effects in vivo.

    PubMed

    Liu, Ji-Xin; Sun, Yan-Hong; Li, Chao-Pin

    2015-04-01

    Demodex is a type of permanent obligatory parasite, which can be found on the human body surface. Currently, drugs targeting Demodex usually result in adverse effects and have a poor therapeutic effect. Thus, the aim of the present study was to investigate the use of Chinese crude medicine volatile oils for targeting and inhibiting Demodex in vitro . The volatile oils of six Chinese crude medicines were investigated, including clove, orange fruit, Manchurian wildginger, cinnamon bark, Rhizome Alpiniae Officinarum and pricklyash peel, which were extracted using a distillation method. The exercise status of Demodex folliculorum and Demodex brevis and the antiparasitic effects of the volatile oils against the two species were observed using microscopy. A skin irritation test was used to examine the irritation intensity of the volatile oils. In addition, an acute toxicity test was utilized to observe the toxicity effects of the volatile oils on the skin. Xin Fumanling ointment was employed as a positive control to identify the therapeutic effects of the volatile oils. The results indicated that all six volatile oils were able to kill Demodex efficiently. In particular, the clove volatile oil was effective in inducing optimized anti- Demodex activity. The lethal times of the volatile oils were significantly decreased compared with the Xin Fumanling ointment (P<0.05). Furthermore, the skin irritation test results indicated that the clove volatile oil did not trigger any irritation (0.2 and 0.3 points for intact and scratched skin, respectively), and had a safety equal to that of distilled water. There were not any adverse effects observed following application of the clove volatile oil on the intact or scratched skin. In conclusion, the volatile oils of Chinese crude medicines, particularly that of clove, demonstrated an evident anti- Demodex activity and were able to kill Demodex effectively and safely in vivo .

  17. Methods to improve the PVD coatability of brass by using diffusion barriers

    NASA Astrophysics Data System (ADS)

    Langer, Bernd

    Previous work involving PVD coatings on brass has used a combination of multilayers consisting of electroplated films like nickel or chromium and deposited decorative PVD coatings like TiN, TiAIN or ZrN systems. The disadvantages of these systems are the combination of wet electrochemistry and high tech vacuum processes. Furthermore the allergic reaction to nickel and the toxic nature of Cr(VI) must be considered.There is a need for intermediate layers to 'seal-off the brass in order to avoid the evaporation of zinc in vacuum using a diffusion barrier. Furthermore the intermediate layers are required to act as a corrosion barrier.This thesis reports on the development of PVD coatings on heat sensitive brass substrate materials utilising ABS technology with Al, CuAl8 and Nb targets as vapour sources.The brass pretreatment includes careful grinding, polishing and cleaning steps as well as steered arc metal ion etching using the above target materials. The coatings are produced at temperatures between 100 and 250°C in the unbalanced magnetron mode, including layers made from Al, Al-Nb, CuA18, CuAl8-Nb and Nb.Scratch adhesion and Rockwell indentation tests are found not to be directly applicable to the system of soft brass and ductile coating(s). Therefore a new classification for both scratch and indentation tests was defined. The best adhesion was shown by the CuA18 coatings on brass. Corrosion tests showed good results for the Al coatings and poor results for the pure Nb coatings directly applied on brass. The best corrosion result was obtained with a CuAl8-Nb layer system. This layer system also offers very good barrier behaviour concerning Zn diffusion.Other investigations like Glow Discharge Optical Emission Spectroscopy (GDOES), Scanning Electron Microscopy (SEM) imaging, Transmission Electron Microscopy (TEM) and X-ray Diffraction (XRD) were undertaken to characterise the new coating systems for brass.

  18. A review of the influence of growth factors and cytokines in in vitro human keratinocyte migration.

    PubMed

    Peplow, Philip V; Chatterjee, Marissa P

    2013-04-01

    Keratinocyte migration from the wound edge is a crucial step in the reepithelization of cutaneous wounds. Growth factors and cytokines, released from cells that invade the wound matrix, play an important role, and several in vitro assays have been performed to elucidate this. The purposes of this study were to review in vitro human studies on keratinocyte migration to identify those growth factors or cytokines that stimulate keratinocyte migration and whether these assays might serve as a screening procedure prior to testing combinations of growth factors or cytokines to promote wound closure in vivo. Research papers investigating effect of growth factors and cytokines on human keratinocyte migration in vitro were retrieved from library sources, PubMed databases, reference lists of papers, and searches of relevant journals. Fourteen different growth factors and cytokines enhanced migration in scratch wound assay and HGF together with TGF-β, and IGF-1 with EGF, were more stimulatory than either growth factor alone. HGF with TGF-β1 had a greater chemokinetic effect than either growth factor alone in transmigration assay. TGF-β1, FGF-7, FGF-2 and AGF were chemotactic to keratinocytes. EGF, TGF-α, IL-1α, IGF and MGSA enhanced cell migration on ECM proteins. Many growth factors and cytokines enhanced migration of keratinocytes in vitro, and certain combinations of growth factors were more stimulatory than either alone. These and other combinations that stimulate keratinocyte migration in vitro should be tested for effect on wound closure and repair in vivo. The scratch wound assay provides a useful, inexpensive and easy-to-perform screening method for testing individual or combinations of growth factors or cytokines, or growth factors combined with other modalities such as laser irradiation, prior to performing wound healing studies with laboratory animals. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Three-Body Abrasion Testing Using Lunar Dust Simulants to Evaluate Surface System Materials

    NASA Technical Reports Server (NTRS)

    Kobrick, Ryan L.; Budinski, Kenneth G.; Street, Kenneth W., Jr.; Klaus, David M.

    2010-01-01

    Numerous unexpected operational issues relating to the abrasive nature of lunar dust, such as scratched visors and spacesuit pressure seal leaks, were encountered during the Apollo missions. To avoid reoccurrence of these unexpected detrimental equipment problems on future missions to the Moon, a series of two- and three-body abrasion tests were developed and conducted in order to begin rigorously characterizing the effect of lunar dust abrasiveness on candidate surface system materials. Two-body scratch tests were initially performed to examine fundamental interactions of a single particle on a flat surface. These simple and robust tests were used to establish standardized measurement techniques for quantifying controlled volumetric wear. Subsequent efforts described in the paper involved three-body abrasion testing designed to be more representative of actual lunar interactions. For these tests, a new tribotester was developed to expose samples to a variety of industrial abrasives and lunar simulants. The work discussed in this paper describes the three-body hardware setup consisting of a rotating rubber wheel that applies a load on a specimen as a loose abrasive is fed into the system. The test methodology is based on ASTM International (ASTM) B611, except it does not mix water with the abrasive. All tests were run under identical conditions. Abraded material specimens included poly(methyl methacrylate) (PMMA), hardened 1045 steel, 6061-T6 aluminum (Al) and 1018 steel. Abrasives included lunar mare simulant JSC- 1A-F (nominal size distribution), sieved JSC-1A-F (<25 m particle diameter), lunar highland simulant NU-LHT-2M, alumina (average diameter of 50 m used per ASTM G76), and silica (50/70 mesh used per ASTM G65). The measured mass loss from each specimen was converted using standard densities to determine total wear volume in cm3. Abrasion was dominated by the alumina and the simulants were only similar to the silica (i.e., sand) on the softer materials of aluminum and PMMA. The nominal JSC- 1A-F consistently showed more abrasion wear than the sieved version of the simulant. The lunar dust displayed abrasivity to all of the test materials, which are likely to be used in lunar landing equipment. Based on this test experience and pilot results obtained, recommendations are made for systematic abrasion testing of candidate materials intended for use in lunar exploration systems and in other environments with similar dust challenges.

  20. Backside Wear Analysis of Retrieved Acetabular Liners with a Press-Fit Locking Mechanism in Comparison to Wear Simulation In Vitro.

    PubMed

    Puente Reyna, Ana Laura; Jäger, Marcus; Floerkemeier, Thilo; Frecher, Sven; Delank, Karl-Stefan; Schilling, Christoph; Grupp, Thomas M

    2016-01-01

    Backside wear due to micromotion and poor conformity between the liner and its titanium alloy shell may contribute to the high rates of retroacetabular osteolysis and consequent aseptic loosening. The purpose of our study was to understand the wear process on the backside of polyethylene liners from two acetabular cup systems, whose locking mechanism is based on a press-fit cone in combination with a rough titanium conical inner surface on the fixation area. A direct comparison between in vitro wear simulator tests (equivalent to 3 years of use) and retrieved liners (average 13.1 months in situ) was done in order to evaluate the backside wear characteristics and behavior of these systems. Similar wear scores between in vitro tested and retrieved liners were observed. The results showed that this locking mechanism did not significantly produce wear marks at the backside of the polyethylene liners due to micromotion. In all the analyzed liners, the most common wear modes observed were small scratches at the cranial fixation zone directly below the rough titanium inner surface of the shell. It was concluded that most of the wear marks were produced during the insertion and removal of the liner, rather than during its time in situ.

  1. Jaundice in a pregnant woman.

    PubMed

    Ibrahimi, Sophiane; Mroué, Abbas Ali; Francois, Erik; Jagodzinski, Robert

    2017-01-01

    A 34-year-old woman in the 22nd week of gestation presented with generalized pruritis and weight loss since the first trimester of pregnancy. Physical examination revealed cutaneous scratch lesions, jaundice, and hepatomegaly. Blood tests revealed cholestasis with elevated direct bilirubinemia. Auto-antibody and viral hepatitis tests were negative. Liver ultrasound was normal. The initial diagnosis was cholestasis of pregnancy. However despite treatment with ursodeoxycholic acid, the patient did not improve. Delivery was by cesarean section at the 26th week of pregnancy for obstetrical reasons. A new liver ultrasound showed a heterogeneous nodular mass. Nuclear magnetic resonance (NMR) of the liver showed an 11-cm mass centered on the hilum, dilated intrahepatic bile ducts, involvement of the hepatic veins, and hilar adenopathy. A liver biopsy revealed fibrolamellar hepatocellular carcinoma (FHC). © Acta Gastro-Enterologica Belgica.

  2. High-Throughput Industrial Coatings Research at The Dow Chemical Company.

    PubMed

    Kuo, Tzu-Chi; Malvadkar, Niranjan A; Drumright, Ray; Cesaretti, Richard; Bishop, Matthew T

    2016-09-12

    At The Dow Chemical Company, high-throughput research is an active area for developing new industrial coatings products. Using the principles of automation (i.e., using robotic instruments), parallel processing (i.e., prepare, process, and evaluate samples in parallel), and miniaturization (i.e., reduce sample size), high-throughput tools for synthesizing, formulating, and applying coating compositions have been developed at Dow. In addition, high-throughput workflows for measuring various coating properties, such as cure speed, hardness development, scratch resistance, impact toughness, resin compatibility, pot-life, surface defects, among others have also been developed in-house. These workflows correlate well with the traditional coatings tests, but they do not necessarily mimic those tests. The use of such high-throughput workflows in combination with smart experimental designs allows accelerated discovery and commercialization.

  3. Corrosion resistance tests on NiTi shape memory alloy.

    PubMed

    Rondelli, G

    1996-10-01

    The corrosion performances of NiTi shape memory alloys (SMA) in human body simulating fluids were evaluated in comparison with other implant materials. As for the passivity current in potentiostatic conditions, taken as an index of ion release, the values are about three times higher for NiTi than for Ti6Al4V and austenitic stainless steels. Regarding the localized corrosion, while plain potentiodynamic scans indicated for NiTi alloy good resistance to pitting attack similar to Ti6Al4V, tests in which the passive film is abruptly damaged (i.e. potentiostatic scratch test and modified ASTM F746) pointed out that the characteristics of the passive film formed on NiTi alloy (whose strength can be related to the alloy's biocompatibility) are not as good as those on Ti6Al4V but are comparable or inferior to those on austenitic stainless steels.

  4. Six weeks of Mat Pilates training are enough to improve functional capacity in elderly women.

    PubMed

    Bertoli, Josefina; Biduski, Grazieli Maria; de la Rocha Freitas, Cíntia

    2017-10-01

    The aim of the study was to evaluate the effect of Mat Pilates on the functional capacity (FC) of elderly women before and after six weeks of intervention. Eighteen women aged 62.28 (±2.34) participated in the study. Timed Up and Go test, Timed Up Stairs, Timed Down Stairs, 30-s Chair Stand, Chair Sit-and-Reach and Back Scratch tests were assessed. The results showed significant improvements in all FC tests after six weeks of the Mat Pilates intervention. Summarizing, only six weeks of Mat Pilates training of 60 min per session, three times a week, three series beginning with six repetitions and eight repetitions at the last two weeks of intervention, were enough to improve FC in elderly women. Furthermore, the exercises difficulty increased from beginners to intermediate. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Non-stick syringe needles: Beneficial effects of thin film metallic glass coating

    PubMed Central

    Chu, Jinn P.; Yu, Chia-Chi; Tanatsugu, Yusuke; Yasuzawa, Mikito; Shen, Yu-Lin

    2016-01-01

    This paper reports on the use of Zr-based (Zr53Cu33Al9Ta5) thin film metallic glass (TFMG) for the coating of syringe needles and compares the results with those obtained using titanium nitride and pure titanium coatings. TFMG coatings were shown to reduce insertion forces by ∼66% and retraction forces by ∼72%, when tested using polyurethane rubber block. The benefits of TFMG-coated needles were also observed when tested using muscle tissue from pigs. In nano-scratch tests, the TFMG coatings achieved a coefficient of friction (COF) of just ∼0.05, which is about one order of magnitude lower than those of other coatings. Finite-element modeling also indicates a significant reduction in injection and retraction forces. The COF can be attributed to the absence of grain boundaries in the TFMG coating as well as a smooth surface morphology and low surface free energy. PMID:27573062

  6. Mechanical and tribological properties of crystalline aluminum nitride coatings deposited on stainless steel by magnetron sputtering

    NASA Astrophysics Data System (ADS)

    Choudhary, R. K.; Mishra, S. C.; Mishra, P.; Limaye, P. K.; Singh, K.

    2015-11-01

    Aluminum nitride (AlN) coating is a potential candidate for addressing the problems of MHD pressure drop, tritium permeation and liquid metal corrosion of the test blanket module of fusion reactor. In this work, AlN coatings were grown on stainless steel by magnetron sputtering. Grazing incidence X-ray diffraction measurement revealed that formation of mixed phase (wurtzite and rock salt) AlN was favored at low discharge power and substrate negative biasing. However, at sufficiently high discharge power and substrate bias, (100) oriented wurtzite AlN was obtained. Secondary ion mass spectroscopy showed presence of oxygen in the coatings. The highest value of hardness and Young's modulus were 14.1 GPa and 215 GPa, respectively. Scratch test showed adhesive failure at a load of about 20 N. Wear test showed improved wear resistance of the coatings obtained at higher substrate bias.

  7. Safety assessment of a new single-use small-incision injector for intraocular lens implantation.

    PubMed

    Satanovsky, Alexandra; Ben-Eliahu, Shmuel; Apple, David J; Kleinmann, Guy

    2011-07-01

    To evaluate the safety of a new injector, the Raysert R-INJ-04/18, for implantation of the C-flex intraocular lens (IOL). Ophthalmology Department, Kaplan Medical Center, Rehovot, Israel. Experimental study. Sixty IOLs were subdivided into 2 equally sized groups. Group A IOLs were injected using the established R-INJ-04 injector, and those in Group B were injected with the new injector. The IOLs were injected into a Petri dish. Subsequently, all IOLs and injectors were evaluated macroscopically and microscopically and then photographed under light microscopy (LM). Two IOLs in each group were randomly chosen and sent for evaluation by scanning electron microscopy (SEM) and energy dispersive analysis of x-ray. All remaining IOLs were sent for power and modulation transfer function (MTF) analysis. All Group B IOLs were successfully injected without evident signs of scratching, cracks, or deposits on LM and SEM examination. In Group A, findings were confined to a singular incidence of a small deposit detected on the periphery of the posterior optical surface of the IOL, with corresponding findings detected on the injector nozzle. No signs of scratching, cracks, or deposits were found in the rest of the IOLs or injectors. The power and MTF analyses were within the normal range for all IOLs. The new 1.8 mm external diameter soft-tipped injector for 2.4 to 2.2 mm incisions was shown to be safe for the implantation of the C-flex 21.0 diopter IOL. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  8. Wound healing properties of jojoba liquid wax: an in vitro study.

    PubMed

    Ranzato, Elia; Martinotti, Simona; Burlando, Bruno

    2011-03-24

    The wound healing properties of jojoba (Simmondsia chinensis) liquid wax (JLW) were studied in vitro on HaCaT keratinocytes and human dermal fibroblasts, which are involved in wounded skin repair. JLW cytotoxicity was evaluated by the crystal violet staining and the neutral red uptake endpoint. Induction of wound healing by JLW was assessed by scratch wound assay on cell monolayers. The involvement of signaling pathways was evaluated by the use of the Ca(2+) chelator BAPTA and of kinase inhibitors, and by Western blot analysis of cell lysates using anti-phospho antibodies. Collagen and gelatinase secretion by cells were assayed by in-cell ELISA and zymography analysis, respectively. Cytotoxicity assays showed that the toxic effects of JLW to these cells are extremely low. Scratch wound experiments showed that JLW notably accelerates the wound closure of both keratinocytes and fibroblasts. The use of inhibitors and Western blot revealed that the mechanism of action of JLW is strictly Ca(2+) dependent and requires the involvement of the PI3K-Akt-mTOR pathway and of the p38 and ERK1/2 MAPKs. In addition, JLW was found to stimulate collagen I synthesis in fibroblasts, while no effect was detected on the secretion of MMP-2 and MMP-9 gelatinases by HaCaT or fibroblasts. Taken together, data provide a pharmacological characterization of JLW properties on skin cells and suggest that it could be used in the treatment of wounds in clinical settings. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  9. Daily intake of Jeju groundwater improves the skin condition of the model mouse for human atopic dermatitis.

    PubMed

    Tanaka, Akane; Jung, Kyungsook; Matsuda, Akira; Jang, Hyosun; Kajiwara, Naoki; Amagai, Yosuke; Oida, Kumiko; Ahn, Ginnae; Ohmori, Keitaro; Kang, Kyung-goo; Matsuda, Hiroshi

    2013-03-01

    Drinking water is an important nutrient for human health. The mineral ingredients included in drinking water may affect the physical condition of people. Various kinds of natural water are in circulation as bottled water in developed countries; however, its influence on clinical conditions of patients with certain diseases has not been fully evaluated. In this study, effects of the natural groundwater from Jeju Island on clinical symptoms and skin barrier function in atopic dermatitis (AD) were evaluated. NC/Tnd mice, a model for human AD, with moderate to severe dermatitis were used. Mice were given different natural groundwater or tap water for 8 weeks from 4 weeks of age. Clinical skin severity scores were recorded every week. Scratching analysis and measurement of transepidermal water loss were performed every other week. The pathological condition of the dorsal skin was evaluated histologically. Real-time polymerase chain reaction analysis was performed for cytokine expression in the affected skin. The epidermal hyperplasia and allergic inflammation were reduced in atopic mice supplied with Jeju groundwater when compared to those supplied with tap water or other kinds of natural groundwater. The increase in scratching behavior with the aggravation of clinical severity of dermatitis was favorably controlled. Moreover, transepidermal water loss that reflects skin barrier function was recovered. The early inflammation and hypersensitivity in the atopic skin was alleviated in mice supplied with Jeju groundwater, suggesting its profitable potential on the daily care of patients with skin troubles including AD. © 2013 Japanese Dermatological Association.

  10. Silver oxide nanoparticles embedded silk fibroin spuns: Microwave mediated preparation, characterization and their synergistic wound healing and anti-bacterial activity.

    PubMed

    Babu, Punuri Jayasekhar; Doble, Mukesh; Raichur, Ashok M

    2018-03-01

    The synergistic wound healing and antibacterial activity of silver oxide nanoparticles embedded silk fibroin (Ag 2 O-SF) spuns is reported here. UV-Vis spectro photometric analysis of these spuns showed the surface plasmon resonance (SPR) confirming the formation of the silver oxide nanoparticles (Ag 2 O NPs) on the surface of the silk fibroin (SF). Scanning electron microscope (SEM) and Differential scanning calorimetry (DSC) also confirmed the presence of Ag 2 O NPs on surface of SF. X-ray diffraction (XRD) analysis revealed the crystalline nature of both SF and Ag 2 O-SF. Fourier transform infrared spectroscopy (FT-IR) results showed the different forms of silk (I and II) and their corresponding protein (amide I, II, III) confirmations. Biodegradation study revealed insignificant changes in the morphology of Ag 2 O-SF spuns even after 14 days of immersion in phosphate buffered saline (PBS). Ag 2 O-SF spuns showed excellent antibacterial activity against both pathogen (S. aureus and M. tuberculosis) and non-pathogen (E. coli) bacteria. More importantly, In vitro wound healing (scratch assay) assay revealed fast migration of the T3T fibroblast cells through the scratch area treated with extract of Ag 2 O-SF spuns and the area was completely covered within 24 h. Cytotoxicity assay confirmed the biocompatible nature of the Ag 2 O-SF spuns, thus suggesting an ideal material for wound healing and anti-bacterial applications. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. A thermoreversible hydrogel as a biosynthetic bandage for corneal wound repair.

    PubMed

    Pratoomsoot, Chayanin; Tanioka, Hidetoshi; Hori, Kuniko; Kawasaki, Satoshi; Kinoshita, Shigeru; Tighe, Patrick J; Dua, Harminder; Shakesheff, Kevin M; Rose, Felicity Rosamari A J

    2008-01-01

    Ocular trauma and disorders that lead to corneal blindness account for over 2 million new cases of monocular blindness every year. A popular ocular surface reconstruction therapy, amniotic membrane transplantation, has been shown to aid corneal wound repair. However, the success rates of the procedure are variable. Here, we proposed to bioengineer a novel synthetic material that would serve as a biomimetic corneal bandage. The PLGA-PEG-PLGA triblock copolymer was synthesised via ring-opening polymerisation. Thermoreversible gelation behaviour was investigated at different polymer concentrations (23%, 30%, 35%, 40%, 45%, w/v) at temperatures ranging between 5 and 60 degrees C. Viscoelastic properties were studied in dynamic mechanical analysis with 1 degrees C/min temperature ramp. Cryo-SEM revealed a porous hydrogel with interconnecting networks. No adverse cytotoxicity was observed with an in vitro scratch-wound assay and in in vivo biocompatibility tests. We have demonstrated that the PLGA-PEG-PLGA hydrogel possessed a suitable gelling profile and, for the first time, the biocompatibility properties for this application as a potential bandage for corneal wound repair.

  12. Nano-chemo-mechanical signature of conventional oil-well cement systems: Effects of elevated temperature and curing time

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

    Krakowiak, Konrad J., E-mail: kjkrak@mit.edu; Thomas, Jeffrey J., E-mail: JThomas39@slb.com; Musso, Simone, E-mail: SMusso@slb.com

    2015-01-15

    With ever more challenging (T,p) environments for cementing applications in oil and gas wells, there is a need to identify the fundamental mechanisms of fracture resistant oil well cements. We report results from a multi-technique investigation of behavior and properties of API class G cement and silica-enriched cement systems subjected to hydrothermal curing from 30 °C to 200 °C; including electron probe microanalysis, X-ray diffraction, thermogravimetry analysis, electron microscopy, neutron scattering (SANS), and fracture scratch testing. The results provide a new insight into the link between system chemistry, micro-texture and micro-fracture toughness. We suggest that the strong correlation found betweenmore » chemically modulated specific surface and fracture resistance can explain the drop in fracture properties of neat oil-well cements at elevated temperatures; the fracture property enhancement in silica-rich cement systems, between 110° and 175 °C; and the drop in fracture properties of such systems through prolonged curing over 1 year at 200 °C.« less

  13. Influence of deposition temperature on WTiN coatings tribological performance

    NASA Astrophysics Data System (ADS)

    Londoño-Menjura, R. F.; Ospina, R.; Escobar, D.; Quintero, J. H.; Olaya, J. J.; Mello, A.; Restrepo-Parra, E.

    2018-01-01

    WTiN films were grown on silicon and stainless-steel substrates using the DC magnetron sputtering technique. The substrate temperature was varied taking values of 100 °C, 200 °C, 300 °C, and 400 °C. X-ray diffraction analysis allowed us to identify a rock salt-type face centered cubic (FCC) structure, with a lattice parameter of approximately 4.2 nm, a relatively low microstrain (deformations at microscopy level, between 4.7% and 6.7%), and a crystallite size of a few nanometers (11.6 nm-31.5 nm). The C1s, N1s, O1s, Ti2p, W4s, W4p, W4d and W4f narrow spectra were obtained using X-ray photoelectron spectroscopy (XPS) and depending on the substrate temperature, the deconvoluted spectra presented different binding energies. Grain sizes and roughness (approximately 4 nm) of films were determined using atomic force microscopy. Scratch and pin on disc tests were conducted, showing better performance of the film grown at 200 °C. This sample exhibited a lower roughness, coefficient of friction, and wear rate.

  14. Bubble formation in microgravity

    NASA Technical Reports Server (NTRS)

    Antar, Basil N.

    1996-01-01

    An extensive experimental program was initiated for the purpose of understanding the mechanisms leading to bubble generation during fluid handling procedures in a microgravity environment. Several key fluid handling procedures typical for PCG experiments were identified for analysis in that program. Experiments were designed to specifically understand how such procedures can lead to bubble formation. The experiments were then conducted aboard the NASA KC-135 aircraft which is capable of simulating a low gravity environment by executing a parabolic flight attitude. However, such a flight attitude can only provide a low gravity environment of approximately 10-2go for a maximum period of 30 seconds. Thus all of the tests conducted for these experiments were designed to last no longer than 20 seconds. Several experiments were designed to simulate some of the more relevant fluid handling procedures during protein crystal growth experiments. These include submerged liquid jet cavitation, filling of a cubical vessel, submerged surface scratch, attached drop growth, liquid jet impingement, and geysering experiments. To date, four separate KC-135 flight campaigns were undertaken specifically for performing these experiments. However, different experiments were performed on different flights.

  15. A study of the relationship between depression symptom and physical performance in elderly women.

    PubMed

    Lee, Yang Chool

    2015-12-01

    Depression is a general public health problem; there is an association between regular exercise or vigorous physical activity and depression. Physical activity has positive physical, mental, and emotional effects. The purpose of this study was to examine the relationship between depression symptom and physical performance in elderly women. A total of 173 elderly women aged 65 to 80 participated in this study. We evaluated elderly women using the 6-min walk, grip-strength, 30-sec arm curl, 30-sec chair stand, 8-foot up and go, back scratch, and chair sit and reach, and unipedal stance, measured the body mass index (BMI), and depression symptom assessed using Korean version of the Geriatric Depression Scale (GDS-K). The collected data were analyzed using descriptive statistics, correlation analysis, paired t-tests, and simple linear regression using IBM SPSS Statistics ver. 21.0. There were significant correlations between GDS-K and the 6-min walk, 30-sec chair stand, 30-sec arm curl, chair sit and reach, 8-foot up and go, and grip strength tests (P<0.05), but not BMI, back strength, and unipedal stance. When divided into two groups (GDS-K score≥14 and GDS-K score<14), there was a difference between the two groups in the 6-min walk, 30-sec chair stand, 30-sec arm curl test, chair sit and reach, 8-foot up and go test, and grip strength test performances. Physical performance factors were strongly associated with depression symptom, suggesting that physical performance improvements may play an important role in preventing depression.

  16. A study of the relationship between depression symptom and physical performance in elderly women

    PubMed Central

    Lee, Yang Chool

    2015-01-01

    Depression is a general public health problem; there is an association between regular exercise or vigorous physical activity and depression. Physical activity has positive physical, mental, and emotional effects. The purpose of this study was to examine the relationship between depression symptom and physical performance in elderly women. A total of 173 elderly women aged 65 to 80 participated in this study. We evaluated elderly women using the 6-min walk, grip-strength, 30-sec arm curl, 30-sec chair stand, 8-foot up and go, back scratch, and chair sit and reach, and unipedal stance, measured the body mass index (BMI), and depression symptom assessed using Korean version of the Geriatric Depression Scale (GDS-K). The collected data were analyzed using descriptive statistics, correlation analysis, paired t-tests, and simple linear regression using IBM SPSS Statistics ver. 21.0. There were significant correlations between GDS-K and the 6-min walk, 30-sec chair stand, 30-sec arm curl, chair sit and reach, 8-foot up and go, and grip strength tests (P<0.05), but not BMI, back strength, and unipedal stance. When divided into two groups (GDS-K score≥14 and GDS-K score<14), there was a difference between the two groups in the 6-min walk, 30-sec chair stand, 30-sec arm curl test, chair sit and reach, 8-foot up and go test, and grip strength test performances. Physical performance factors were strongly associated with depression symptom, suggesting that physical performance improvements may play an important role in preventing depression. PMID:26730389

  17. Cat scratch disease of the eye: a case report and literature review.

    PubMed

    Alaan, Kristina; Fisher, Melanie; Ellis, Brian

    2014-01-01

    This is the case of a middle-aged male with no other medical issues who presented with acute, unilateral visual disturbance. In lieu of specific ophthalmologic findings, his age and presentation, he was treated for presumed inflammatory process. It was only after steroids and the results of serological testing that an infectious agent was determined. He was eventually diagnosed with ocular Bartonellosis. He was treated with oral doxycycline and rifampin and slowly improved. The thesis of this case report is that a thorough history prior to rapid and somewhat presumptive treatment may have prevented unnecessary immunosuppression and delay in appropriate antimicrobial therapy.

  18. SEM Evaluation of Surrounding Enamel after Finishing of Composite Restorations- Preliminary Results

    NASA Astrophysics Data System (ADS)

    Iovan, G.; Stoleriu, S.; Solomon, S.; Ghiorghe, A.; Sandu, A. V.; Andrian, S.

    2017-06-01

    The purpose of this study was to analyze the surface characteristics of the enamel adjacent to composite resin after finishing the restoration with different diamond and tungsten carbide burs. The topography of enamel was observed by using a scanning electron microscope. Finishing with extra-/ultra-fine carbide burs, and extra-fine diamond burs resulted in smooth surfaces. In few areas some superficial scratches with no clinical relevance were observed. Deep grooves were observed on the surface of enamel when fine diamond burs were used. Finishing of composite restorations with coarse burs should be avoided when there is a high risk of touching and scratching adjacent enamel during the procedure.

  19. Optically transparent, scratch-resistant, diamond-like carbon coatings

    DOEpatents

    He, Xiao-Ming; Lee, Deok-Hyung; Nastasi, Michael A.; Walter, Kevin C.; Tuszewski, Michel G.

    2003-06-03

    A plasma-based method for the deposition of diamond-like carbon (DLC) coatings is described. The process uses a radio-frequency inductively coupled discharge to generate a plasma at relatively low gas pressures. The deposition process is environmentally friendly and scaleable to large areas, and components that have geometrically complicated surfaces can be processed. The method has been used to deposit adherent 100-400 nm thick DLC coatings on metals, glass, and polymers. These coatings are between three and four times harder than steel and are therefore scratch resistant, and transparent to visible light. Boron and silicon doping of the DLC coatings have produced coatings having improved optical properties and lower coating stress levels, but with slightly lower hardness.

  20. Substance P(1-7) antagonizes substance P-induced aversive behaviour in mice.

    PubMed

    Sakurada, T; Kuwahara, H; Takahashi, K; Sakurada, S; Kisara, K; Terenius, L

    1988-12-19

    Substance P (SP) and its fragments were administered intrathecally into awake mice. SP and C-terminal fragments caused dose-dependent reciprocal hindlimb scratching responses. SP(5-11) was more potent than SP not only in inducing scratching response but also in inducing aversive behaviour including licking and biting. SP(1-7) induced no behavioural reactions. However, when low doses of SP(1-7) (1.0-4.0 pmol) were injected simultaneously with SP or SP(5-11) (0.1 nmol), aversive behaviours induced by SP or SP(5-11) were significantly reduced. These results indicate that SP(1-7) formed endogenously could modulate the actions of SP or SP(5-11) in the spinal cord.

  1. Investigation of Specificity of Mechanical Properties of Hard Materials on Nanoscale with Use of SPM- Nanohardness Tester

    NASA Astrophysics Data System (ADS)

    Lvova, N. A.; Blank, V. D.; Gogolinskiy, K. V.; Kulibaba, V. F.

    2007-04-01

    Specifisities of deformation on nanoscale of hard brittle materials with the hardness exceeding 10 GP by means of scanning probe microscope - nanohardness tester "NanoScan" are investigated. It is found, that pile-up is forming at scratching of sample surface with use of diamond indenter. Heigh of this pile-up depends on hardness and elastic modulus of the material. Definition of the contact area without taking into account height of pile-up leads to an overestimation of hardness values. At scratching of silicon carbide surface a transition from plastic flow to fracture is found out. The results received allowed to estimate fracture toughness KIC for silicon carbide.

  2. Optical and Scratch Resistant Properties of Diamondlike Carbon Films Deposited with Single and Dual Ion Beams

    NASA Technical Reports Server (NTRS)

    Kussmaul, Michael T.; Bogdanski, Michael S.; Banks, Bruce A.; Mirtich, Michael J.

    1993-01-01

    Amorphous diamond-like carbon (DLC) films were deposited using both single and dual ion beam techniques utilizing filament and hollow cathode ion sources. Continuous DLC films up to 3000 A thick were deposited on fused quartz plates. Ion beam process parameters were varied in an effort to create hard, clear films. Total DLC film absorption over visible wavelengths was obtained using a Perkin-Elmer spectrophotometer. An ellipsometer, with an Ar-He laser (wavelength 6328 A) was used to determine index of refraction for the DLC films. Scratch resistance, frictional, and adherence properties were determined for select films. Applications for these films range from military to the ophthalmic industries.

  3. Optical and scratch resistant properties of diamondlike carbon films deposited with single and dual ion beams

    NASA Technical Reports Server (NTRS)

    Kussmaul, Michael T.; Bogdanski, Michael S.; Banks, Bruce A.; Mirtich, Michael J.

    1993-01-01

    Amorphous diamondlike carbon (DLC) films were deposited using both single and dual ion beam techniques utilizing filament and hollow cathode ion sources. Continuous DLC films up to 3000 A thick were deposited on fused quartz plates. Ion beam process parameters were varied in an effort to create hard, clear films. Total DLC film absorption over visible wavelengths was obtained using a Perkin-Elmer spectrophotometer. An ellipsometer, with an Ar-He laser (wavelength 6328 A) was used to determine index of refraction for the DLC films. Scratch resistance and frictional and adherence properties were determined for select films. Applications for these films range from military to the ophthalmic industries.

  4. Impact of solids on composite materials

    NASA Technical Reports Server (NTRS)

    Bronson, Arturo; Maldonado, Jerry; Chern, Tzong; Martinez, Francisco; Mccord-Medrano, Johnnie; Roschke, Paul N.

    1987-01-01

    The failure modes of composite materials as a result of low velocity impact were investigated by simulating the impact with a finite element analysis. An important facet of the project is the modeling of the impact of a solid onto cylindrical shells composed of composite materials. The model under development will simulate the delamination sustained when a composite material encounters impact from another rigid body. The computer equipment was installed, the computer network tested, and a finite element method model was developed to compare results with known experimental data. The model simulated the impact of a steel rod onto a rotating shaft. Pre-processing programs (GMESH and TANVEL) were developed to generate node and element data for the input into the three dimensional, dynamic finite element analysis code (DYNA3D). The finite element mesh was configured with a fine mesh near the impact zone and a coarser mesh for the impacting rod and the regions surrounding the impacting zone. For the computer simulation, five impacting loads were used to determine the time history of the stresses, the scribed surface areas, and the amount of ridging. The processing time of the computer codes amounted from 1 to 4 days. The calculated surface area were within 6-12 percent, relative error when compated to the actual scratch area.

  5. Pen-chant: Acoustic emissions of handwriting and drawing

    NASA Astrophysics Data System (ADS)

    Seniuk, Andrew G.

    The sounds generated by a writing instrument ('pen-chant') provide a rich and underutilized source of information for pattern recognition. We examine the feasibility of recognition of handwritten cursive text, exclusively through an analysis of acoustic emissions. We design and implement a family of recognizers using a template matching approach, with templates and similarity measures derived variously from: smoothed amplitude signal with fixed resolution, discrete sequence of magnitudes obtained from peaks in the smoothed amplitude signal, and ordered tree obtained from a scale space signal representation. Test results are presented for recognition of isolated lowercase cursive characters and for whole words. We also present qualitative results for recognizing gestures such as circling, scratch-out, check-marks, and hatching. Our first set of results, using samples provided by the author, yield recognition rates of over 70% (alphabet) and 90% (26 words), with a confidence of +/-8%, based solely on acoustic emissions. Our second set of results uses data gathered from nine writers. These results demonstrate that acoustic emissions are a rich source of information, usable---on their own or in conjunction with image-based features---to solve pattern recognition problems. In future work, this approach can be applied to writer identification, handwriting and gesture-based computer input technology, emotion recognition, and temporal analysis of sketches.

  6. The effect of adhesive strength of hydroxyapatite coating on the stability of hydroxyapatite-coated prostheses in vivo at the early stage of implantation

    PubMed Central

    Duan, Yonghong; Zhu, Shu; Guo, Fei; Zhu, Jinyu; Li, Mao; Ma, Jie

    2012-01-01

    Introduction With the increase in joint revision surgery after arthroplasty, defects of hydroxyapatite (HA)-coated prostheses have been observed increasingly often. These defects adversely affect the prosthetic stability in vivo. This study has analyzed the potential effect of the adhesive strength of HA coating on the stability of HA-coated prostheses in vivo after its implantation. Material and methods Sixty experimental rabbits were divided into HA- and Ti-coated groups. HA-coated prostheses were implanted into the bilateral epicondyle of rabbits femurs. Ti-coated prostheses were implanted as control. At different time points(4, 9, and 15 weeks) after implantation, bone tissue samples were fetched out respectively for histomorphometric analysis. Push-out testing was used to detect the ultimate shear strength at the bone-prosthesis interface. Scanning electron microscope (SEM) observation and energy-dispersive X-ray spectroscopy (EDX) analysis were used to observe the changes in surface composition of the prostheses after the ultimate shear strength testing. The coating adhesive strength of two kinds of coatings were also examined by scratch testing. Results Hydroxyapatite coating has an obvious advantage in facilitating osteogenesis and its plays a critical role in the stability of prostheses. However, the ultimate shear strength of HA-coated prostheses is much lower than that of Ti-coated implants (p < 0.01). Further study has demonstrated that the stability of HA-coated prostheses in vivo is affected by the relatively low adhesive strength between coating and substrate. Conclusions Obvious advantage in facilitating osteogenesis around HA-coated prostheses is not the only factor that determines the stability of prostheses in vivo. PMID:22661990

  7. TRPA1 controls inflammation and pruritogen responses in allergic contact dermatitis

    PubMed Central

    Liu, Boyi; Escalera, Jasmine; Balakrishna, Shrilatha; Fan, Lu; Caceres, Ana I.; Robinson, Eve; Sui, Aiwei; McKay, M. Craig; McAlexander, M. Allen; Herrick, Christina A.; Jordt, Sven E.

    2013-01-01

    Allergic contact dermatitis is a common skin disease associated with inflammation and persistent pruritus. Transient receptor potential (TRP) ion channels in skin-innervating sensory neurons mediate acute inflammatory and pruritic responses following exogenous stimulation and may contribute to allergic responses. Genetic ablation or pharmacological inhibition of TRPA1, but not TRPV1, inhibited skin edema, keratinocyte hyperplasia, nerve growth, leukocyte infiltration, and antihistamine-resistant scratching behavior in mice exposed to the haptens, oxazolone and urushiol, the contact allergen of poison ivy. Hapten-challenged skin of TRPA1-deficient mice contained diminished levels of inflammatory cytokines, nerve growth factor, and endogenous pruritogens, such as substance P (SP) and serotonin. TRPA1-deficient sensory neurons were defective in SP signaling, and SP-induced scratching behavior was abolished in Trpa1−/− mice. SP receptor antagonists, such as aprepitant inhibited both hapten-induced cutaneous inflammation and scratching behavior. These findings support a central role for TRPA1 and SP in the integration of immune and neuronal mechanisms leading to chronic inflammatory responses and pruritus associated with contact dermatitis.—Liu, B., Escalera, J., Balakrishna, S., Fan, L., Caceres, A. I., Robinson, E., Sui, A., McKay, M. C., McAlexander, M. A., Herrick, C. A., Jordt, S. E. TRPA1 controls inflammation and pruritogen responses in allergic contact dermatitis. PMID:23722916

  8. Simulation and Experimental Study on Surface Formation Mechanism in Machining of SiCp/Al Composites

    NASA Astrophysics Data System (ADS)

    Du, Jinguang; Zhang, Haizhen; He, Wenbin; Ma, Jun; Ming, Wuyi; Cao, Yang

    2018-03-01

    To intuitively reveal the surface formation mechanism in machining of SiCp/Al composites, in this paper the removal mode of reinforced particle and aluminum matrix, and their influence on surface formation mechanism were analyzed by single diamond grit cutting simulation and single diamond grit scratch experiment. Simulation and experiment results show that when the depth of cut is small, the scratched surface of the workpiece is relatively smooth; however, there are also irregular pits on the machined surface. When increasing the depth of cut, there are many obvious laminar structures on the scratched surface, and the surface appearance becomes coarser. When the cutting speed is small, the squeezing action of abrasive grit on SiC particles plays a dominant role in the extrusion of SiC particles. When increasing the cutting speed, SiC particles also occur broken or fractured; but the machined surface becomes smooth. When machining SiCp/Al composites, the SiC may happen in such removal ways, such as fracture, debonding, broken, sheared, pulled into and pulled out, etc. By means of reasonably developing micro cutting finite element simulation model of SiCp/Al composites could be used to analyze the surface formation process and particle removal way in different machining conditions.

  9. Correlation of bond strength with surface roughness using a new roughness measurement technique.

    PubMed

    Winkler, M M; Moore, B K

    1994-07-01

    The correlation between shear bond strength and surface roughness was investigated using new surface measurement methods. Bonding agents and associated resin composites were applied to set amalgam after mechanically roughening its surface. Surface treatments were noe (as set against glass), 80 grit, and 600 grit abrasive paper. Surface roughness (R(a) as measured parallel and perpendicular (+) to the direction of the polishing scratches and true profile length were measured. A knife-edge was applied (rate = 2.54 mm/min) at the bonding agent/amalgam interface of each sample until failure. Coefficients of determination for mean bond strength vs either roughness (R(a), of profile length were significantly higher for measurements in parallel directions than for those measurements in (+) directions. The shear bond strength to set amalgam for a PENTA-containing adhesives system (L.D. Caulk Division) was not significantly different from that of a PENTA-free adhesive (3M Dental Products Division), even though PENTA has been reported to increase bond strength to nonprecious metals. The shear bond strength of resin composite to amalgam is correlated to surface roughness when it is measured parallel to the polishing scratches. This correlation is significantly lower when surface roughness is measured in the typical manner, perpendicular to the polishing scratches.

  10. Earliest evidence of dental caries manipulation in the Late Upper Palaeolithic

    PubMed Central

    Oxilia, Gregorio; Peresani, Marco; Romandini, Matteo; Matteucci, Chiara; Spiteri, Cynthianne Debono; Henry, Amanda G.; Schulz, Dieter; Archer, Will; Crezzini, Jacopo; Boschin, Francesco; Boscato, Paolo; Jaouen, Klervia; Dogandzic, Tamara; Broglio, Alberto; Moggi-Cecchi, Jacopo; Fiorenza, Luca; Hublin, Jean-Jacques; Kullmer, Ottmar; Benazzi, Stefano

    2015-01-01

    Prehistoric dental treatments were extremely rare, and the few documented cases are known from the Neolithic, when the adoption of early farming culture caused an increase of carious lesions. Here we report the earliest evidence of dental caries intervention on a Late Upper Palaeolithic modern human specimen (Villabruna) from a burial in Northern Italy. Using Scanning Electron Microscopy we show the presence of striations deriving from the manipulation of a large occlusal carious cavity of the lower right third molar. The striations have a “V”-shaped transverse section and several parallel micro-scratches at their base, as typically displayed by cutmarks on teeth. Based on in vitro experimental replication and a complete functional reconstruction of the Villabruna dental arches, we confirm that the identified striations and the associated extensive enamel chipping on the mesial wall of the cavity were produced ante-mortem by pointed flint tools during scratching and levering activities. The Villabruna specimen is therefore the oldest known evidence of dental caries intervention, suggesting at least some knowledge of disease treatment well before the Neolithic. This study suggests that primitive forms of carious treatment in human evolution entail an adaptation of the well-known toothpicking for levering and scratching rather than drilling practices. PMID:26179739

  11. Evidence for heterogeneity of astrocyte de-differentiation in vitro: astrocytes transform into intermediate precursor cells following induction of ACM from scratch-insulted astrocytes.

    PubMed

    Yang, Hao; Qian, Xin-Hong; Cong, Rui; Li, Jing-wen; Yao, Qin; Jiao, Xi-Ying; Ju, Gong; You, Si-Wei

    2010-04-01

    Our previous study definitely demonstrated that the mature astrocytes could undergo a de-differentiation process and further transform into pluripotential neural stem cells (NSCs), which might well arise from the effect of diffusible factors released from scratch-insulted astrocytes. However, these neurospheres passaged from one neurosphere-derived from de-differentiated astrocytes possessed a completely distinct characteristic in the differentiation behavior, namely heterogeneity of differentiation. The heterogeneity in cell differentiation has become a crucial but elusive issue. In this study, we show that purified astrocytes could de-differentiate into intermediate precursor cells (IPCs) with addition of scratch-insulted astrocyte-conditioned medium (ACM) to the culture, which can express NG2 and A2B5, the IPCs markers. Apart from the number of NG2(+) and A2B5(+) cells, the percentage of proliferative cells as labeled with BrdU progressively increased with prolonged culture period ranging from 1 to 10 days. Meanwhile, the protein level of A2B5 in cells also increased significantly. These results revealed that not all astrocytes could de-differentiate fully into NSCs directly when induced by ACM, rather they generated intermediate or more restricted precursor cells that might undergo progressive de-differentiation to generate NSCs.

  12. Comparison of pregnancy rates between patients with and without local endometrial scratching before intrauterine insemination.

    PubMed

    Senocak, G C; Yapca, O E; Borekci, B

    2017-11-01

    To determine the implantation success of local endometrial injury in patients undergoing intrauterine insemination following ovulation induction with gonadotropins as an infertility treatment. In this prospective randomized controlled trial, ovulation induction was performed with gonadotropins in 80 patients following intrauterine insemination. In 40 patients, local endometrial injury (scratch) was performed in the midluteal phase of the cycle preceding ovarian stimulation with a Novak curette to the posterior side of the endometrial cavity. Fifteen pregnancies (37.5%) and 11 clinical pregnancies (27.5%) occurred in the intervention group, whereas eight pregnancies (20%) and five clinical pregnancies (12.5%) occurred in the control group. Although the pregnancy rates and clinical pregnancy rates were increased in the intervention group, no statistically significant difference was found between the intervention and control groups (pregnancy rates: P=0.084; clinical pregnancy rates: P=0.094). Performing local endometrial injury (scratch) in the cycle preceding ovulation induction in patients with a diagnosis of infertility and indication for intrauterine insemination increased the pregnancy and clinical pregnancy rates. This increase was not, however, statistically significant. More randomized, controlled, prospective studies with larger patient numbers are required before the use of iatrogenic induction of local endometrial injury can be recommended in routine clinical practice. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  13. Thermoregulation, scratch, itch and sleep deficits in children with eczema.

    PubMed

    Camfferman, D; Short, M A; Kennedy, J D; Gold, M; Kohler, M; Lushington, K

    2016-09-01

    Successful sleep onset and maintenance is associated with a reduction in core temperature, facilitated by heat loss at the distal periphery. Problems with initiating and maintaining sleep in children with eczema may relate to impaired thermoregulatory mechanisms, which also contribute to itching and scratching. Our hypothesis was that nocturnal distal skin temperature in eczematous children would be lower than controls, and would also be related to poor sleep quality. We compared overnight polysomnography and distal (finger) and proximal (clavicle) skin temperature in 18 children with eczema and 15 controls (6-16 years). Children with eczema had longer periods of nocturnal wakefulness (mean [SD] = 88.8 [25.8] vs. 44.3 [35.6] min) and lower distal temperatures (34.1 [0.6] °C vs. 34.7 [0.4] °C) than controls, whereas proximal temperature and the distal-proximal gradient were not significantly different. In children with eczema, a higher distal temperature was associated with indicators of poor sleep quality, whereas lower distal temperature was related to more scratching events during sleep. In conclusion, our findings indicate complex interrelationships among eczema, thermoregulation and sleep, and further, that deficits in thermoregulatory mechanisms may contribute to sleep disturbances in children with eczema. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Acidosis counteracts itch tachyphylaxis to consecutive pruritogen exposure dependent on acid-sensing ion channel 3.

    PubMed

    Jiang, Yi-Ming; Huang, Chen; Peng, Zhong; Han, Shao-Ling; Li, Wei-Guang; Zhu, Michael Xi; Xu, Tian-Le

    2017-01-01

    Tachyphylaxis of itch refers to a markedly reduced scratching response to consecutive exposures of a pruritogen, a process thought to protect against tissue damage by incessant scratching and to become disrupted in chronic itch. Here, we report that a strong stimulation of the Mas-related G-protein-coupled receptor C11 by its agonist, Ser-Leu-Ile-Gly-Arg-Leu-NH 2 (SL-NH 2 ) or bovine adrenal medulla 8-22 peptide, via subcutaneous injection in mice induces tachyphylaxis to the subsequent application of SL-NH 2 to the same site. Notably, co-application of acid and SL-NH 2 following the initial injection of the pruritogen alone counteracted itch tachyphylaxis by augmenting the scratching behaviors in wild-type but not in acid-sensing ion channel 3-null, animals. Using an activity-dependent silencing strategy, we identified that acid-sensing ion channel 3-mediated itch enhancement mainly occurred via the Mas-related G-protein-coupled receptor C11-responsive sensory neurons. Together, our results indicate that acid-sensing ion channel 3, activated by concomitant acid and certain pruritogens, constitute a novel signaling pathway that counteracts itch tachyphylaxis to successive pruritogenic stimulation, which likely contributes to chronic itch associated with tissue acidosis.

  15. Acidosis counteracts itch tachyphylaxis to consecutive pruritogen exposure dependent on acid-sensing ion channel 3

    PubMed Central

    Jiang, Yi-Ming; Huang, Chen; Peng, Zhong; Han, Shao-Ling; Li, Wei-Guang; Zhu, Michael Xi; Xu, Tian-Le

    2017-01-01

    Tachyphylaxis of itch refers to a markedly reduced scratching response to consecutive exposures of a pruritogen, a process thought to protect against tissue damage by incessant scratching and to become disrupted in chronic itch. Here, we report that a strong stimulation of the Mas-related G-protein-coupled receptor C11 by its agonist, Ser-Leu-Ile-Gly-Arg-Leu-NH2 (SL-NH2) or bovine adrenal medulla 8-22 peptide, via subcutaneous injection in mice induces tachyphylaxis to the subsequent application of SL-NH2 to the same site. Notably, co-application of acid and SL-NH2 following the initial injection of the pruritogen alone counteracted itch tachyphylaxis by augmenting the scratching behaviors in wild-type but not in acid-sensing ion channel 3-null, animals. Using an activity-dependent silencing strategy, we identified that acid-sensing ion channel 3-mediated itch enhancement mainly occurred via the Mas-related G-protein-coupled receptor C11-responsive sensory neurons. Together, our results indicate that acid-sensing ion channel 3, activated by concomitant acid and certain pruritogens, constitute a novel signaling pathway that counteracts itch tachyphylaxis to successive pruritogenic stimulation, which likely contributes to chronic itch associated with tissue acidosis. PMID:28745101

  16. Prosthetic joint infection caused by Pasteurella multocida: a case series and review of literature.

    PubMed

    Honnorat, Estelle; Seng, Piseth; Savini, Hélène; Pinelli, Pierre-Olivier; Simon, Fabrice; Stein, Andreas

    2016-08-20

    Pasteurella multocida is a well-recognized zoonotic agent following dog or cat bites or scratches. Nevertheless, prosthetic joint infection caused by P. multocida are rarely reported. We report here a series of six cases of prosthetic joint infection caused by P. multocida managed at a referral centre for the treatment of bone and joint infection in southern France. We also reviewed the 26 cases reported in literature. The mean age of our cases was 74 years [±8.2, range 63-85]. In majority of our cases (5 cases) were associated with knee prostheses and one case with a hip prosthesis. Most of cases occurred after cat or dog scratches or licks or contact. Diagnoses of prosthetic joint infection caused by P. multocida were made by positive cultures of surgical biopsies or needle aspiration. Mean time delay between prosthetic joint implantation and infection onset was 7.6 years (±5.12 years, range 2-17). Local inflammation, which occurred in all six cases, was the most frequent clinical symptom, followed by pain in five cases, fever and swollen joints in four cases, and a fistula with purulent discharge inside the wound in two cases. The mean time of antibiotic therapy was 8 months. Surgical treatment with prosthesis removal was performed in three cases. Six of our cases were in remission without apparent relapse at 3 years after end of treatment. Prosthetic joint infections caused by P. multocida usually occur after animal scratches or bites, but can occasionally occur after a short animal lick. These infections are usually resulting from a contiguous infection and localized in the knee. An early antibiotic therapy after surgical debridement could avoid prosthetic withdrawal, notably in elderly patients. Patients with prosthetic joints should be warned that animals are potential sources of serious infection and urgent medical advice should be sought if they are bitten or scratched.

  17. Life expectancy of modular Ti6Al4V hip implants: influence of stress and environment.

    PubMed

    Chandra, A; Ryu, J J; Karra, P; Shrotriya, P; Tvergaard, V; Gaisser, M; Weik, T

    2011-11-01

    Stress dependent electrochemical dissolution is identified as one of the key mechanisms governing surface degradation in fretting and crevice corrosion of biomedical implants. The present study focuses on delineating the roles of mechanical stress and chemical conditions on the life expectancy of modular hip implants. First, material removal on a stressed surface of Ti6Al4V subjected to single asperity contact is investigated experimentally to identify the influence of contact load, in-plane stress and chemical environment on mean wear rates. A range of known stress levels are applied to the specimen while its surface is mechanically stimulated in different non-reactive to oxidizing aqueous environments. Evolution of surface degradation is monitored, and its mechanism is elucidated. This phase allows estimation of Preston Constant which is later used in the analysis. Second phase of the work is semi-analytical and computational, where, based on the estimated Preston constant and other material and process parameters, the scratch propensity (consisting of magnitude of scratch depth and their frequency per unit area) due to micro-motion in modular hip implants is estimated. The third phase views these scratches as initial notches and utilizes a mixed-mode fatigue crack propagation model to estimate the critical crack length for onset of instability. The number of loading cycles needed to reach this critical crack length is then labeled as the expected life of the implant under given mechanical and chemical conditions. Implications of different material and process conditions to life expectancy of orthopedic implants are discussed. It is observed that transverse micro-motion, compared to longitudinal micro-motion, plays a far more critical role in determining the implant life. Patient body weight, as well as proximity of the joint fluid to its iso-electric point play key roles in determining wear rates and associated life expectancies of modular hip implants. Sustained aeration of joint fluid, as well as proper tolerancing of mating surfaces, along with a proper choice of material microstructure may be utilized to extend implant life. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Vortex energy landscape from real space imaging analysis of YBa2Cu3O7 with different defect structures

    NASA Astrophysics Data System (ADS)

    Luccas, R. F.; Granados, X.; Obradors, X.; Puig, T.

    2014-10-01

    A methodology based on real space vortex image analysis is presented able to estimate semi-quantitatively the relevant energy densities of an arbitrary array of vortices, map the interaction energy distributions and evaluate the pinning energy associated to particular defects. The combined study using nanostructuration tools, a vortex visualization technique and the energy method is seen as an opportunity to estimate vortex pinning potentials strengths. Particularly, spatial distributions of vortex energy densities induced by surface nanoindented scratches are evaluated and compared to those of twin boundaries. This comparative study underlines the remarkable role of surface nanoscratches in pinning vortices and its potentiality in the design of novel devices for pinning and guiding vortex motion.

  19. Effect of topical chamomile on immunohistochemical levels of IL-1β and TNF-α in 5-fluorouracil-induced oral mucositis in hamsters.

    PubMed

    Curra, Marina; Martins, Marco Antonio T; Lauxen, Isabel S; Pellicioli, Ana Carolina A; Sant'Ana Filho, Manoel; Pavesi, Vanessa Christina S; Carrard, Vinicius C; Martins, Manoela D

    2013-02-01

    The aim of the present study was to evaluate the effect of topical chamomile and corticosteroid treatment on the profile of tissue cytokines (IL-1β and TNF-α) in 5-fluorouracil-induced oral mucositis in hamsters. Thirty-six hamsters were randomly separated into three groups (12 animals each): Group I--without treatment (control); Group II-treatment with chamomile (Ad-Muc(®)); and Group III--treatment with corticosteroid (betamethasone elixir- Celestone(®)). The animals received an intraperitoneal injection of 5--fluorouracil on Days 0 and 2. On Days 3 and 4, the buccal mucosa was scratched and therapy was initiated on Day 5. Three animals from each group were killed on Days 0, 5, 10, and 14 and the buccal mucosa was removed. The streptavidin-biotin complex method was used to delineate the in situ distribution, localization, and semiquantitative analysis of IL-1β and TNF-α. Data from the semiquantitative analysis of immunohistochemical staining were comparatively analyzed using the Kruskal-Wallis test, followed by Dunn's multiple comparisons test. The distribution and localization of IL-1β and TNF-α immunolabeling were similar. These proteins exhibited a diffuse pattern distributed throughout the connective tissue. The epithelium and adipose tissue were negative for both proteins. The semiquantitative analysis revealed that immunolabeling of IL-1β and TNF-α increased in all groups with the development of mucositis. On Day 10 (period of peak mucositis), the group treated with chamomile had lower scores for both pro-inflammatory cytokines. Treatment with topical chamomile reduced the tissue levels of IL-1β and TNF-α, thereby demonstrating anti-inflammatory action in oral mucositis in hamsters.

  20. FY07 LDRD Final Report A Fracture Mechanics and Tribology Approach to Understanding Subsurface Damage on Fused Silica during Grinding and Polishing

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

    Suratwala, T I; Miller, P E; Menapace, J A

    The objective of this work is to develop a solid scientific understanding of the creation and characteristics of surface fractures formed during the grinding and polishing of brittle materials, specifically glass. In this study, we have experimentally characterized the morphology, number density, and depth distribution of various surface cracks as a function of various grinding and polishing processes (blanchard, fixed abrasive grinding, loose abrasive, pitch polishing and pad polishing). Also, the effects of load, abrasive particle (size, distribution, foreign particles, geometry, velocity), and lap material (pitch, pad) were examined. The resulting data were evaluated in terms of indentation fracture mechanicsmore » and tribological interactions (science of interacting surfaces) leading to several models to explain crack distribution behavior of ground surfaces and to explain the characteristics of scratches formed during polishing. This project has greatly advanced the scientific knowledge of microscopic mechanical damage occurring during grinding and polishing and has been of general interest. This knowledge-base has also enabled the design and optimization of surface finishing processes to create optical surfaces with far superior laser damage resistance. There are five major areas of scientific progress as a result of this LDRD. They are listed in Figure 1 and described briefly in this summary below. The details of this work are summarized through a number of published manuscripts which are included this LDRD Final Report. In the first area of grinding, we developed a technique to quantitatively and statistically measure the depth distribution of surface fractures (i.e., subsurface damage) in fused silica as function of various grinding processes using mixtures of various abrasive particles size distributions. The observed crack distributions were explained using a model that extended known, single brittle indentation models to an ensemble of loaded, sliding particles. The model illustrates the importance of the particle size distribution of the abrasive and its influence on the resulting crack distribution. The results of these studies are summarized in references 1-7. In the second area of polishing, we conducted a series of experiments showing the influence of rogue particles (i.e., particles in the polishing slurry that are larger than base particles) on the creation of scratches on polished surfaces. Scratches can be thought of a as a specific type of sub-surface damage. The characteristics (width, length, type of fractures, concentration) were explained in terms of the rogue particle size, the rogue particle material, and the viscoelastic properties of the lap. The results of these studies are summarized in references 6-7. In the third area of etching, we conducted experiments aimed at understanding the effect of HF:NH{sub 4}F acid etching on surface fractures on fused silica. Etching can be used as a method: (a) to expose sub-surface mechanical damage, (b) to study the morphology of specific mechanical damage occurring by indentation, and (c) to convert a ground surface containing a high concentration of sub-surface mechanical damage into surface roughness. Supporting models have been developed to describe in detail the effect of etching on the morphology and evolution of surface cracks. The results of these studies are summarized in references 8-9. In the fourth area of scratch forensics or scratch fractography, a set of new scratch forensic rule-of-thumbs were developed in order to aid the optical fabricator and process engineer to interpret the cause of scratches and digs on surfaces. The details of how these rules were developed are described in each of the references included in this summary (1-9). Figure 2 provides as a summary of some of the more commonly used rules-of-thumbs that have been developed in this study. In the fifth and final area of laser damage, we demonstrated that the removal of such surface fractures from the surface during optical fabrication can dramatically improve the laser damage.« less

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