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.
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.
Tribology behavior on scratch tests: Effects of yield strength
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
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
Owner observations regarding cat scratching behavior: an internet-based survey.
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.
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.
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.
Peripheral NMDA Receptor/NO System Blockage Inhibits Itch Responses Induced by Chloroquine in Mice
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
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.
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.
Induction of scratching behaviour in cats: efficacy of synthetic feline interdigital semiochemical.
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.
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.
Withdrawal of repeated morphine enhances histamine-induced scratching responses in mice.
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.
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.
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
The fracture strength of ceramic brackets: a comparative study.
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.
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
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.
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.
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
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.
CAT SCRATCH DISEASE: RESULTS OF COMPLEMENT-FIXATION AND SKIN TESTS
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.
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.
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.
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.
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.
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.
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.
The Neuropeptide Y system regulates both mechanical and histaminergic itch.
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.
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
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.
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
Validation of Scratching Severity as an Objective Assessment for Itch.
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.
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
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
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.
Head-scratching method of the Swainson's warbler
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.
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.
Somatostatin receptor scintigraphy in patients with cat-scratch disease.
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.
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.
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.
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...
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.
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.
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.
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.
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.
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.
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.
Turner, Sarah E; Fedigan, Linda M; Matthews, H Damon; Nakamichi, Masayuki
2012-09-01
Little is known about consequences of disability in nonhuman primates, yet individuals with disabilities can reveal much about behavioral flexibility, innovation, and the capabilities of a species. The Macaca fuscata population surrounding the Awajishima Monkey Center has experienced high rates of congenital limb malformation for at least 40 years, creating a unique opportunity to examine consequences of physical impairment in situ, in a relatively large sample of free-ranging adult monkeys. Here we present behavioral data on 11 disabled adult females and 12 nondisabled controls from 279 hours of randomly ordered 30-minute focal animal follows collected during May-August in 2005, 2006, and 2007. We quantified numerous statistically significant disability-related behavioral differences among females. Disabled females spent less time begging for peanuts from tourists, and employed a behavioral variant of such peanut begging; they had a lower frequency of hand use in grooming and compensated with increased direct use of the mouth or a two-arm pinch technique; and they had a higher frequency of self-scratching, and more use of feet in self-scratching. Self-scratching against substrates was almost exclusively a disability associated behavior. Two females used habitual bipedalism. These differences not withstanding, disabled females behaved similarly to controls in many respects: overall reliance on provisioned and wild foods, time spent feeding, and feeding efficiency did not differ among females, and there was no time difference in behavior performed arboreally or terrestrially. Disabled adult females were able to compensate behaviorally to perform social and life-sustaining activities, modifying existing behaviors to suit their individual physical situations and, occasionally, inventing new ways of doing things. © 2012 Wiley Periodicals, Inc.
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.
Tribological behavior of DLC films deposited on nitrided and post-oxidized stainless steel by PACVD
NASA Astrophysics Data System (ADS)
Dalibon, E. L.; Brühl, S. P.; Heim, D.
2012-06-01
In this work, the tribological behavior and adhesion of DLC films deposited by PACVD on AISI 420 martensitic stainless steel was evaluated. Prior to DLC deposition, the samples were nitrided and some of them also post-oxidized. The films were characterized by Raman and EDS, microhardness was assessed with Vickers indenter and the microstructure was analyzed by OM, SEM, FIB. Fretting and linear reciprocating sliding tests were performed using a WC ball as counterpart, and the adhesion of the DLC films was characterized using the Scratch Test and Rockwell C indentation. Corrosion behavior was evaluated by the Salt Spray Fog Test. The film showed a hardness of only about 1500 HV but it was about 15-20 microns thick. The results of the mechanical tests showed that pre-treatments (nitriding and oxidizing) of the substrate did not have a big influence in the tribological behavior of the coating. However, the nitriding treatment before the DLC coating process reduced the interface stress and enhanced the adhesion. Additionally, all the films evidenced good corrosion resistance in a saline environment, better than the AISI 420 itself.
Nocebo Effects and Scratching Behaviour in Itch.
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.
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.
Crack propagation and the material removal mechanism of glass-ceramics by the scratch test.
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.
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.
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.
Value of the pinnal-pedal reflex in the diagnosis of canine scabies.
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.
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…
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.
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.
Behavioral Treatment of Aggression in the Mentally Retarded: A Review.
ERIC Educational Resources Information Center
Feldstein, Jerome H.
The paper reviews 34 behavioral treatment studies (1967-1983) examining reduction of aggressive behavior in mentally retarded people. Research reviewed was limited to treatment of physically aggressive responses such as hits, kicks, bites, chokes, scratches, and throwing objects by persons designated as mentally retarded. Among results reported…
TRPA1 controls inflammation and pruritogen responses in allergic contact dermatitis
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
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).
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.
SLIDING DIRECTION-DEPENDENCE OF POLYETHYLENE WEAR FOR METAL COUNTERFACE TRAVERSE OF SEVERE SCRATCHES
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
Neuroticism and stress: the role of displacement behavior.
Mohiyeddini, Changiz; Bauer, Stephanie; Semple, Stuart
2015-01-01
Neuroticism is linked with an impaired ability to cope with stress and is an important risk factor for stress-related disorders. Hence, there is interest in exploring the behavioral correlates of neuroticism and how such behaviors may moderate the link between neuroticism and the response to stress. Displacement behavior - activity such as face touching and scratching - is important to investigate in this respect, as recent studies indicate that such behavior is linked to negative emotional states and has an important stress coping function. Here, we explored the relationship between neuroticism, displacement behavior, and stress in a healthy population of men. This was a cross-sectional, quasiexperimentally controlled study. We assessed participants' levels of neuroticism, and then during a Trier Social Stress Test quantified displacement behavior, physiological, and cognitive indices of the stress response; after the test we measured the self-reported experience of stress. Displacement behavior was negatively correlated with self-reported experience, physiological, and cognitive measures of stress and moderated the relationships between neuroticism, self-reported experience, and cognitive index of stress. Our results suggest displacement behavior plays an important role in shaping the link between neuroticism and the response to stress.
Quality Evaluation of Coatings by Automatic Scratch Testing
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
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.
Cat scratch disease during pregnancy.
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.
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.
The effect of propofol on intrathecal morphine-induced pruritus and its mechanism.
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.
... Development Infections Diseases & Conditions Pregnancy & Baby Nutrition & Fitness Emotions & Behavior School & Family Life First Aid & Safety Doctors & ... scratch your skin because of a bug bite , eczema , or poison ivy , germs may find a way ...
Park, Paula; Schachter, Steven; Yaksh, Tony
2010-01-01
Huperzine A (HupA) is an alkaloid isolated from the Chinese club moss Huperzia serrata and has been used for improving memory, cognitive and behavioral function in patients with Alzheimer's disease in China. It has NMDA antagonist and anticholinesterase activity and has shown anticonvulsant and antinociceptive effects in preliminary studies when administered intraperitoneally to mice. To better characterize the antinociceptive effects of HupA at the spinal level, Holtzman rats were implanted with intrathecal catheters to measure thermal escape latency using Hargreaves thermal escape testing system and flinching behavior using the formalin test. Intrathecal (IT) administration of HupA showed a dose-dependent increase in thermal escape latency with an ED50 of 0.57 μg. Atropine reversed the increase in thermal escape latency produced by 10 μg HupA, indicating an antinociceptive mechanism through muscarinic cholinergic receptors. The formalin test showed that HupA decreased flinching behavior in a dose-dependent manner. Atropine also reversed the decrease in flinching behavior caused by 10 μg HupA. A dose-dependent increase of side effects including scratching, biting, and chewing tails was observed, although antinociceptive effects were observed in doses that did not produce any adverse effects. PMID:20026382
Park, Paula; Schachter, Steven; Yaksh, Tony
2010-02-05
Huperzine A (HupA) is an alkaloid isolated from the Chinese club moss Huperzia serrata and has been used for improving memory, cognitive and behavioral function in patients with Alzheimer's disease in China. It has NMDA antagonist and anticholinesterase activity and has shown anticonvulsant and antinociceptive effects in preliminary studies when administered intraperitoneally to mice. To better characterize the antinociceptive effects of HupA at the spinal level, Holtzman rats were implanted with intrathecal catheters to measure thermal escape latency using Hargreaves thermal escape testing system and flinching behavior using the formalin test. Intrathecal (IT) administration of HupA showed a dose-dependent increase in thermal escape latency with an ED50 of 0.57 microg. Atropine reversed the increase in thermal escape latency produced by 10 microg HupA, indicating an antinociceptive mechanism through muscarinic cholinergic receptors. The formalin test showed that HupA decreased flinching behavior in a dose-dependent manner. Atropine also reversed the decrease in flinching behavior caused by 10 microg HupA. A dose-dependent increase of side effects including scratching, biting, and chewing tails was observed, although antinociceptive effects were observed in doses that did not produce any adverse effects. (c) 2009 Elsevier Ireland Ltd. All rights reserved.
Mao, J; Coghill, R C; Kellstein, D E; Frenk, H; Mayer, D J
1992-03-06
The present study examined the effects of intrathecal (i.t.) injection of calcitonin gene-related peptide (CGRP) on caudally directed biting and scratching induced by i.t. substance P (SP), bombesin (BBS), strychnine (STR), and kainic acid (KA). CGRP alone (5.25, 10.5 and 21 nmol) had no effect on these behaviors, but CGRP pretreatment produced a dose-related enhancement of behaviors induced by SP or BBS, but not by KA or STR. 2-Amino-5-phosphonovaleric acid (APV, 25 nmol), a selective N-methyl-D-aspartate (NMDA) receptor antagonist, did not block the CGRP potentiation of SP and BBS induced behaviors. CGRP, however, failed to enhance scratching and biting induced by a SP analogue [pGlu5-Mephe8-MeGly9]SP(5-11) (Dime-C7) that is resistant to enzymatic degradation by SP endopeptidase. These findings demonstrate that CGRP potentiates SP induced behavioral responses via inhibition of neuropeptide degradation and that this mechanism may serve as a physiological mechanism of SP modulation.
An Experimental Itch Model in Monkeys
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
Nanomechanical Behavior of High Gas Barrier Multilayer Thin Films.
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.
Contagious behavior: an alternative approach to mirror-like phenomena.
Provine, Robert R
2014-04-01
Contagious behaviors such as yawning and itching/scratching have mirror-like properties and clearly defined stimulus and motor parameters; they are also relatively easy to study and should be part of the debate about mirror neurons and the neurological mechanisms of social behavior. The broadly tuned, multimodal stimuli of contagious behavior challenge present accounts of mirror mechanisms that focus on specific, mirrored acts.
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.
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.
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.
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
Osthole inhibits histamine-dependent itch via modulating TRPV1 activity.
Yang, Niu-Niu; Shi, Hao; Yu, Guang; Wang, Chang-Ming; Zhu, Chan; Yang, Yan; Yuan, Xiao-Lin; Tang, Min; Wang, Zhong-Li; Gegen, Tana; He, Qian; Tang, Kehua; Lan, Lei; Wu, Guan-Yi; Tang, Zong-Xiang
2016-05-10
Osthole, an active coumarin isolated from Cnidium monnieri (L.) Cusson, has long been used in China as an antipruritic herbal medicine; however, the antipruitic mechanism of osthole is unknown. We studied the molecular mechanism of osthole in histamine-dependent itch by behavioral test, Ca(2+) imaging, and electrophysiological experiments. First, osthole clearly remitted the scratching behaviors of mice induced with histamine, HTMT, and VUF8430. Second, in cultured dorsal root ganglion (DRG) neurons, osthole showed a dose-dependent inhibitory effect to histamine. On the same neurons, osthole also decreased the response to capsaicin and histamine. In further tests, the capsaicin-induced inward currents were inhibited by osthole. These results revealed that osthole inhibited histamine-dependent itch by modulating TRPV1 activity. This study will be helpful in understanding how osthole exerts anti-pruritus effects and suggests that osthole may be a useful treatment medicine for histamine-dependent itch.
Osthole inhibits histamine-dependent itch via modulating TRPV1 activity
Yang, Niu-Niu; Shi, Hao; Yu, Guang; Wang, Chang-Ming; Zhu, Chan; Yang, Yan; Yuan, Xiao-Lin; Tang, Min; Wang, Zhong-li; Gegen, Tana; He, Qian; Tang, Kehua; Lan, Lei; Wu, Guan-Yi; Tang, Zong-Xiang
2016-01-01
Osthole, an active coumarin isolated from Cnidium monnieri (L.) Cusson, has long been used in China as an antipruritic herbal medicine; however, the antipruitic mechanism of osthole is unknown. We studied the molecular mechanism of osthole in histamine-dependent itch by behavioral test, Ca2+ imaging, and electrophysiological experiments. First, osthole clearly remitted the scratching behaviors of mice induced with histamine, HTMT, and VUF8430. Second, in cultured dorsal root ganglion (DRG) neurons, osthole showed a dose-dependent inhibitory effect to histamine. On the same neurons, osthole also decreased the response to capsaicin and histamine. In further tests, the capsaicin-induced inward currents were inhibited by osthole. These results revealed that osthole inhibited histamine-dependent itch by modulating TRPV1 activity. This study will be helpful in understanding how osthole exerts anti-pruritus effects and suggests that osthole may be a useful treatment medicine for histamine-dependent itch. PMID:27160770
A 31-year-old man with bilateral blurry vision and floaters.
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.
A nanometric cushion for enhancing scratch and wear resistance of hard films
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
Low-Temperature Self-Healing of a Microcapsule-Type Protective Coating.
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.
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...
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
Effect of gamma irradiation on the wear behavior of human tooth dentin.
Qing, Ping; Huang, Shengbin; Gao, ShanShan; Qian, LinMao; Yu, HaiYang
2016-12-01
The objective of this study was to evaluate the effect of gamma irradiation on the wear behavior of human tooth dentin in terms of possible alterations in crystallinity, grain size, and composition. Human premolars (n = 19) were collected to obtain the perpendicular or parallel to the direction of the dentin tubule specimens. Each specimen was subjected to 60 Gy of gamma irradiation, in daily increments of 2 Gy. The nanoscratch tests were conducted. The scratch traces were observed via scanning electron microscope (SEM) and surface profilometer. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to investigate the alteration of crystallography and chemical composition of dentin after irradiation. The change of surface microhardness (SMH) was also evaluated. The nanoscratch results showed that the friction coefficient of dentin after irradiation became higher, and the depths and widths of scratch were greater than that of dentin before irradiation. Additionally, irradiation decreased the crystallinity of dentin and induced the formation of bigger crystals. The carbonate/mineral ratio was increased. Furthermore, a significant reduction in microhardness after irradiation was observed. The main damage mechanisms consisted of the formation of delamination and crack in both the specimens cut perpendicular and parallel to tubule dentin after irradiation. Irradiation affected directly the wear behavior of tooth dentin, accompanied by the alterations in crystallography, chemical composition, and surface microhardness of dentin. This would help extend understanding the influence of irradiation on dentin and provide suggestions for selecting more suitable materials for irradiated tooth.
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
ERIC Educational Resources Information Center
Lang, Russell; Didden, Robert; Machalicek, Wendy; Rispoli, Mandy; Sigafoos, Jeff; Lancioni, Giulio; Mulloy, Austin; Regester, April; Pierce, Nigel; Kang, Soyeon
2010-01-01
Skin-picking is a type of self-injurious behavior involving the pulling, scratching, lancing, digging, or gouging of one's own body. It is associated with social impairment, and increased medical and mental health concerns. While there are several reports showing that skin-picking is common in individuals with developmental disabilities, knowledge…
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
Tribology Based Research and Training for Underrepresented Minorities
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
Lactic acid bacteria increase antiallergic effect of Artemisia princeps pampanini SS-1.
Lee, Seung-Hoon; Shin, Yong-Wook; Bae, Eun-Ah; Lee, Bomi; Min, Sungwon; Baek, Nam-In; Chung, Hae-Gon; Kim, Nam-Jae; Kim, Dong-Hyun
2006-09-01
Artemisia princeps Pampanini, which is called Ssajuarissuk in Korean (SS-1), was fermented with lactic acid bacteria (LAB) and their passive cutaneous anaphylaxis reaction-inhibitory activity was investigated. Of these fermented agents, SS-1 extract fermented with Bifidobacterium infantis K-525 (F-SS-1) most effectively inhibited the release of P-hexosamindase from RBL-2H3 cells induced IgE. In IgE-induced RBL-2H3 cells, F-SS-1 inhibited proinflammatory cytokines IL-6 and TNF-alpha mRNA expression. Oral administration of SS-1 and F-SS-1 to mice inhibited passive cutaneous anaphylaxis (PCA) reaction induced by IgE and scratching behaviors induced by compound 48/80. The inhibitory activity of F-SS-1 against scratching behaviors was more effective than that of SS-1. These findings suggest that the fermentation of SS-1 with LAB can increase its antiallergic activity.
Sakurada, T; Tan-No, K; Yamada, T; Sakurada, S; Kisara, K
1990-12-01
The effects of peptidase inhibitors were examined upon behavioural responses including scratch, bite and lick produced by intrathecal (IT) injection of substance P (SP) and neurokinin A (NK A) in mice. Phosphoramidon (0.002-2.0 nmol), an endopeptidase-24.11 inhibitor, simultaneously injected with SP or NK A, remarkably enhanced and prolonged SP- or NK A-induced behavioural response in a dose-dependent manner. The behavioural response to SP was significantly increased by 2.0 nmol of bestatin, an aminopeptidase inhibitor, but not by 1.0 nmol. Captopril, an angiotensin-converting enzyme inhibitor, was without effect on both tachykinin-induced responses. When phosphoramidon was injected together with bestatin and captopril which have no significant effect alone, SP- or NK A-induced behavioral response was significantly increased. These data suggest that endopeptidase-24.11 may be an important enzyme responsible for terminating of SP- or NK A-induced behavioral response at the spinal cord level.
Collective Behavior of Brain Tumor Cells: the Role of Hypoxia
NASA Astrophysics Data System (ADS)
Khain, Evgeniy; Katakowski, Mark; Hopkins, Scott; Szalad, Alexandra; Zheng, Xuguang; Jiang, Feng; Chopp, Michael
2013-03-01
We consider emergent collective behavior of a multicellular biological system. Specifically we investigate the role of hypoxia (lack of oxygen) in migration of brain tumor cells. We performed two series of cell migration experiments. The first set of experiments was performed in a typical wound healing geometry: cells were placed on a substrate, and a scratch was done. In the second set of experiments, cell migration away from a tumor spheroid was investigated. Experiments show a controversy: cells under normal and hypoxic conditions have migrated the same distance in the ``spheroid'' experiment, while in the ``scratch'' experiment cells under normal conditions migrated much faster than under hypoxic conditions. To explain this paradox, we formulate a discrete stochastic model for cell dynamics. The theoretical model explains our experimental observations and suggests that hypoxia decreases both the motility of cells and the strength of cell-cell adhesion. The theoretical predictions were further verified in independent experiments.
Low-Temperature Self-Healing of a Microcapsule-Type Protective Coating
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
Cat scratch disease and lymph node tuberculosis in a colon patient with cancer.
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.
FROZEN RAW FOODS AS SKIN-TESTING MATERIALS—Further Studies of Use in Cases of Allergic Disorders
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
Determination of the Wound Healing Potentials of Medicinal Plants Historically Used in Ghana
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
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.
... 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 ...
Massen, Jorg J. M.; Šlipogor, Vedrana; Gallup, Andrew C.
2016-01-01
Behavioral contagion is suggested to promote group coordination that may facilitate activity transitions, increased vigilance, and state matching. Apart from contagious yawning, however, very little attention has been given to this phenomenon, and studies on contagious yawning in primates have so far only focused on Old World monkeys and apes. Here we studied behavioral contagion in common marmosets, a species for which group coordination and vigilance are paramount. In particular, we investigated the contagiousness of yawning, stretching, scratching, tongue protrusion, gnawing, and scent-marking. We coded these behaviors from 14 adult marmosets, from two different social groups. During testing sessions, animals were separated into groups of four individuals for 20-min observation periods, across three distinct diurnal time points (morning, midday, and afternoon) to test for circadian patterns. We observed almost no yawning (0.12 yawns/h) and very little stretching behavior. For all other behaviors, which were more common, we found several temporal and inter-individual differences (i.e., sex, age, dominance status) predictive of these responses. Moreover, we found that gnawing and scent-marking, which almost always co-occurred as a fixed-action pattern, were highly temporally clustered within observation sessions. We discuss the relative absence of yawning in marmosets as well as the possible function of contagious scent-marking, and provide suggestions for future research into the proximate and ultimate functions of these behaviors in marmosets. PMID:27563294
Determining the direction of tooth grinding: an in vitro study.
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.
Mahovetz, L M; Young, L J; Hopkins, W D
2016-06-01
The mark/rouge test has been used to assess mirror self-recognition (MSR) in many species. Despite consistent evidence of MSR in great apes, genetic or non-genetic factors may account for the individual differences in behavioral responses that have been reported. We examined whether vasopressin receptor gene (AVPR1A) polymorphisms are associated with MSR-related behaviors in chimpanzees since vasopressin has been implicated in the development and evolution of complex social relations and cognition and chimpanzees are polymorphic for the presence of the RS3-containing DupB region. We compared a sample of DupB+/- and DupB-/- chimpanzees on a mark test to assess its role on social behavior toward a mirror. Chimpanzees were administered two, 10-min sessions where frequencies of mirror-guided self-directed behaviors, contingent actions and other social behaviors were recorded. Approximately one-third showed evidence of MSR and these individuals exhibited more mirror-guided self-exploratory behaviors and mouth contingent actions than chimpanzees not classified as passers. Moreover, DupB+/- males exhibited more scratching and agonistic behaviors than other male and female cohorts. Our findings support previous studies demonstrating individual differences in MSR abilities in chimpanzees and suggest that AVPR1A partly explains individual differences in MSR by influencing the behavioral reactions of chimpanzees in front of a mirror. © 2016 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.
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.
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
The effect of wasabi rhizome extract on atopic dermatitis-like symptoms in HR-1 hairless mice.
Nagai, Masashi; Okunishi, Isao
2009-04-01
We investigated the effect of wasabi rhizome extract on atopic dermatitis (AD) model mice. The wasabi extract was fed to the HR-1 hairless mice, which develop AD-like symptoms with a special diet (HR-AD diet). The extract was expected to reduce the symptoms induced. Wasabi rhizome-containing HR-AD diet (5% and 10%) reduced the scratching behavior, and the 10% wasabi rhizome HR-AD diet significantly reduced scratching behavior on days 28, 35 and 42. Plasma components (histamine, eotaxin, IgE and thymus and activation-regulated chemokine (TARC)) were decreased in the 10% wasabi rhizome HR-AD diet. In histopathological examinations (toluidine blue (T.B.), major basic protein (MBP), CD4, IL-4, IL-5, eotaxin, TARC and IgE), the wasabi rhizome-containing HR-AD diet (5% and 10%) significantly reduced the number of positive stained cells. These results suggested that the wasabi rhizome extract improved the AD-like symptoms of HR-1 hairless mice.
Generation of Scratches and Their Effects on Laser Damage Performance of Silica Glass
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
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.
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.
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.
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.
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.
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.
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.
Bites and Scratches (For Parents)
... 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 ...
A Novel Marking Reader for Progressive Addition Lenses Based on Gabor Holography.
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.
The Digital Woodlouse--Scaffolding in Science-Related Scratch Projects
ERIC Educational Resources Information Center
Weigend, Michael
2014-01-01
Scientific issues like the behavior of wild and domesticated animals can serve as a motivation to learn programming concepts. Instead of following a systematic introduction, the students directly dive into programming and start immediately with their projects. In this constructionist approach the educational challenge for the teacher is to provide…
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.
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
Shared Components of Rhythm Generation for Locomotion and Scratching Exist Prior to Motoneurons
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
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.
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.
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
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
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.
Thompson, Robin J.; Mickelsen, Scott L.; Smith, Spencer C.; Alvarenga, Isabella C.; Gross, Kathy L.
2018-01-01
Veterinarians and pet owners have limited ability to assess pruritic behaviors in dogs. This pilot study assessed the capacity of the Vetrax® triaxial accelerometer to measure these behaviors in six dogs with pruritus likely due to environmental allergens. Dogs wore the activity monitor for two weeks while consuming their usual pet food (baseline), then for eight weeks while consuming a veterinary-exclusive pet food for dogs with suspected non-food-related skin conditions (Hill’s Prescription Diet® Derm DefenseTM Canine dry food). Veterinarians and owners completed questionnaires during baseline, phase 1 (days 1–28) and phase 2 (days 29–56) without knowledge of the activity data. Continuous 3-axis accelerometer data was processed using proprietary behavior recognition algorithms and analyzed using general linear mixed models with false discovery rate-adjusted p values. Veterinarian-assessed overall clinical signs of pruritus were significantly predicted by scratching (β 0.176, p = 0.008), head shaking (β 0.197, p < 0.001) and sleep quality (β −0.154, p < 0.001), while owner-assessed quality of life was significantly predicted by scratching (β −0.103, p = 0.013) and head shaking (β −0.146, p < 0.001). Among dogs exhibiting pruritus signs eating the veterinary-exclusive food, the Vetrax® sensor provided an objective assessment of clinically relevant pruritic behaviors that agreed with owner and veterinarian reports. PMID:29337903
Pain and functional capacity in female fibromyalgia patients.
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.
Whitlock, John A.
2011-01-01
Background As gigantic herbivores, sauropod dinosaurs were among the most important members of Mesozoic communities. Understanding their ecology is fundamental to developing a complete picture of Jurassic and Cretaceous food webs. One group of sauropods in particular, Diplodocoidea, has long been a source of debate with regard to what and how they ate. Because of their long lineage duration (Late Jurassic-Late Cretaceous) and cosmopolitan distribution, diplodocoids formed important parts of multiple ecosystems. Additionally, fortuitous preservation of a large proportion of cranial elements makes them an ideal clade in which to examine feeding behavior. Methodology/Principal Findings Hypotheses of various browsing behaviors (selective and nonselective browsing at ground-height, mid-height, or in the upper canopy) were examined using snout shape (square vs. round) and dental microwear. The square snouts, large proportion of pits, and fine subparallel scratches in Apatosaurus, Diplodocus, Nigersaurus, and Rebbachisaurus suggest ground-height nonselective browsing; the narrow snouts of Dicraeosaurus, Suuwassea, and Tornieria and the coarse scratches and gouges on the teeth of Dicraeosaurus suggest mid-height selective browsing in those taxa. Comparison with outgroups (Camarasaurus and Brachiosaurus) reinforces the inferences of ground- and mid-height browsing and the existence of both non-selective and selective browsing behaviors in diplodocoids. Conclusions/Significance These results reaffirm previous work suggesting the presence of diverse feeding strategies in sauropods and provide solid evidence for two different feeding behaviors in Diplodocoidea. These feeding behaviors can subsequently be tied to paleoecology, such that non-selective, ground-height behaviors are restricted to open, savanna-type environments. Selective browsing behaviors are known from multiple sauropod clades and were practiced in multiple environments. PMID:21494685
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.
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.
A longitudinal dataset of five years of public activity in the Scratch online community.
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.
Hydrogen sulfide-induced itch requires activation of Cav3.2 T-type calcium channel in mice
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
NASA Astrophysics Data System (ADS)
Nickelsen, Simin; Moghadam, Afsaneh Dorri; Ferguson, J. B.; Rohatgi, Pradeep
2015-10-01
In the present study, the wetting behavior of surfaces of various common metallic materials used in the water industry including C84400 brass, commercially pure aluminum (99.0% pure), Nickle-Molybdenum alloy (Hastelloy C22), and 316 Stainless Steel prepared by mechanical abrasion and contact angles of several materials after mechanical abrasion were measured. A model to estimate roughness factor, Rf, and fraction of solid/oil interface, ƒso, for surfaces prepared by mechanical abrasion is proposed based on the assumption that abrasive particles acting on a metallic surface would result in scratches parallel to each other and each scratch would have a semi-round cross-section. The model geometrically describes the relation between sandpaper particle size and water/oil contact angle predicted by both the Wenzel and Cassie-Baxter contact type, which can then be used for comparison with experimental data to find which regime is active. Results show that brass and Hastelloy followed Cassie-Baxter behavior, aluminum followed Wenzel behavior and stainless steel exhibited a transition from Wenzel to Cassie-Baxter. Microstructural studies have also been done to rule out effects beyond the Wenzel and Cassie-Baxter theories such as size of structural details.
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.
Corrosion behavior of aluminum doped diamond-like carbon thin films in NaCl aqueous solution.
Khun, N W; Liu, E
2010-07-01
Aluminum doped diamond-like carbon (DLC:Al) thin films were deposited on n-Si(100) substrates by co-sputtering a graphite target under a fixed DC power (650 W) and an aluminum target under varying DC power (10-90 W) at room temperature. The structure, adhesion strength and surface morphology of the DLC:Al films were characterized by X-ray photoelectron spectroscopy (XPS), micro-scratch testing and atomic force microscopy (AFM), respectively. The corrosion performance of the DLC:Al films was investigated by means of potentiodynamic polarization testing in a 0.6 M NaCl aqueous solution. The results showed that the polarization resistance of the DLC:Al films increased from about 18 to 30.7 k(omega) though the corrosion potentials of the films shifted to more negative values with increased Al content in the films.
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.
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…
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…
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.
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.
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.
Petersson, Maria; Uvnäs-Moberg, Kerstin; Nilsson, Anne; Gustafson, Lise-Lotte; Hydbring-Sandberg, Eva; Handlin, Linda
2017-01-01
We have previously shown that dog–owner interaction results in increasing oxytocin levels in owners and dogs, decreasing cortisol levels in owners but increasing cortisol levels in dogs. The present study aimed to further investigate whether oxytocin and cortisol levels in the previously tested owners and dogs were associated with their behaviors during the interaction experiment. Ten female volunteer dog–owners and their male Labrador dogs participated in a 60 min interaction experiment with interaction taking place during 0–3 min and blood samples for analysis of oxytocin and cortisol were collected at 0, 1, 3, 5, 15, 30, and 60 min. The entire experiment was videotaped and the following variables were noted; the different types (stroking, scratching, patting and activating touch, i.e., scratching and patting combined) as well as the frequency of touch applied by the owner, the number of times the owner touched her dog, the dog’s positions and time spent in each position. Correlations were analyzed between the behavioral variables and basal oxytocin levels, maximum oxytocin levels, delta oxytocin levels, basal cortisol levels and cortisol levels at 15 min. Owners with low oxytocin levels before and during the interaction touched their dogs more frequently (0 min: Rs = -0.683, p = 0.042; oxytocin maximum: Rs = -0.783, p = 0.013). The lower the dogs’ oxytocin levels during the interaction, the more stroking they received (Rs = -0.717, p = 0.041). The more frequently activating touch was applied by the owner, the higher the dogs’ cortisol levels became (15 min: Rs = 0.661, p = 0.038). The higher the owners’ maximum oxytocin level the fewer position changes the dogs made (Rs = -0.817, p = 0.007) and the shorter time they spent sitting (Rs = -0.786, p = 0.036), whereas the higher the owners’ basal cortisol levels, the longer time the dogs spent standing (0 min: Rs = 0.683, p = 0.041). In conclusion, oxytocin and cortisol levels, both in dogs and in their owners, are associated with the way the owners interact with their dogs and also with behaviors caused by the interaction. PMID:29081760
Petersson, Maria; Uvnäs-Moberg, Kerstin; Nilsson, Anne; Gustafson, Lise-Lotte; Hydbring-Sandberg, Eva; Handlin, Linda
2017-01-01
We have previously shown that dog-owner interaction results in increasing oxytocin levels in owners and dogs, decreasing cortisol levels in owners but increasing cortisol levels in dogs. The present study aimed to further investigate whether oxytocin and cortisol levels in the previously tested owners and dogs were associated with their behaviors during the interaction experiment. Ten female volunteer dog-owners and their male Labrador dogs participated in a 60 min interaction experiment with interaction taking place during 0-3 min and blood samples for analysis of oxytocin and cortisol were collected at 0, 1, 3, 5, 15, 30, and 60 min. The entire experiment was videotaped and the following variables were noted; the different types (stroking, scratching, patting and activating touch, i.e., scratching and patting combined) as well as the frequency of touch applied by the owner, the number of times the owner touched her dog, the dog's positions and time spent in each position. Correlations were analyzed between the behavioral variables and basal oxytocin levels, maximum oxytocin levels, delta oxytocin levels, basal cortisol levels and cortisol levels at 15 min. Owners with low oxytocin levels before and during the interaction touched their dogs more frequently (0 min: R s = -0.683, p = 0.042; oxytocin maximum: R s = -0.783, p = 0.013). The lower the dogs' oxytocin levels during the interaction, the more stroking they received ( R s = -0.717, p = 0.041). The more frequently activating touch was applied by the owner, the higher the dogs' cortisol levels became (15 min: R s = 0.661, p = 0.038). The higher the owners' maximum oxytocin level the fewer position changes the dogs made ( R s = -0.817, p = 0.007) and the shorter time they spent sitting ( R s = -0.786, p = 0.036), whereas the higher the owners' basal cortisol levels, the longer time the dogs spent standing (0 min: R s = 0.683, p = 0.041). In conclusion, oxytocin and cortisol levels, both in dogs and in their owners, are associated with the way the owners interact with their dogs and also with behaviors caused by the interaction.
Effects of subliminally presented auditory suggestions of itching on scratching behavior.
Mitchell, C W
1995-02-01
This study investigated effects of masked verbal suggestions of itching, utilizing a design closely analogous to commercially available subliminal audiotapes. Students participated in 1 of 3 groups (n = 21): an experimental group listened to an audiotape with music masking suggestions of itching, Control Group 1 listened to an audiotape with music only, and Control Group 2 listened to suggestions of itching presented supraliminally. Dependent variables included both behavioral and self-report measures of itching. There was no evidence of influence from subliminal suggestion; however, results assessing the influence of supraliminally presented suggestions were mixed for self-report and behavioral measures.
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…
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…
Reliability and feasibility of physical fitness tests in female fibromyalgia patients.
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.
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.
Sonography of cat scratch disease.
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.
Endometrial 'scratching': what the data show.
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.
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.
[Bartonella henselae, an ubiquitous agent of proteiform zoonotic disease].
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.
Evidence that displacement activities facilitate behavioural transitions in ring-tailed lemurs.
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.
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.
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.
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
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
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.
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.
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.
... 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. ...
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.
Simultaneous measurement of friction and wear in hip simulators.
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.
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.
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.
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.
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...
Isolated mediastinal necrotizing granulomatous lymphadenopathy due to cat-scratch disease.
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.
Cat scratch disease presenting as acute mastoiditis.
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.
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.
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.
Effects of nanoscale coatings on reliability of MEMS ohmic contact switches
NASA Astrophysics Data System (ADS)
Tremper, Amber Leigh
This thesis examines how the electrical and mechanical behavior of Au thin films is altered by the presence of ultra-thin metallic coatings. To examine the mechanical behavior, nanoindentation, nano-scratch, and atomic force microscopy (AFM) testing was performed. The electrical behavior was evaluated through Kelvin probe contact resistance measurements. This thesis shows that ultra-thin, hard, ductile coatings on a softer, ductile underlying layer (such as Ru or Pt on Au) had a significant effect on mechanical behavior of the system, and can be tailored to control the deformation resistance of the thin film system. Despite Ru and Pt having a higher hardness and plane strain modulus than Au, the Ru and Pt coatings decreased both the hardness and plane strain modulus of the layered system when the indentation depth was on the order of the coating thickness. Alternately, when the indentation depth was several times the coating thickness, the ductile, plastically hard, elastically stiff layer significantly hardened the contact response. These results correlate well with membrane stress theoretical predictions, and demonstrate that membrane theory can be applied even when the ratio of indentation depth, h, to coating thickness, t, is very large ( h/t<10). The transition from film-substrate models to membrane models occurs when the indent penetration depth to coating thickness ratio is less than ˜0.5. When the electrical behavior of the Ru-coated Au films was examined, it was found that all the measured resistances of the Au-only film and Ru-coated systems were several orders of magnitude larger than those predicted by Holm's law, but were still in good agreement with previously reported values in the literature. Previous studies attributed the high contact resistances to a variety of causes, including the buildup of an insulating contamination layer. This thesis determined the cause of the deviations to be large sheet resistance contributions to the total measured resistance. Further, studies on aged samples (with thicker contamination layers) conclusively showed that, while contamination increases the contact resistance, it also increases the dependence on force. This thesis also details that the relative contribution of contact resistance to the total measured resistance can be maximized by decreasing the probe spacing and tip radius. AFM testing of the layered systems showed that the coated samples had larger predicted plane strain moduli than the Au sample, in contrast to the nanoindentation testing. Thus, when the contact depth was kept sufficiently small, the contact stiffness increased as predicted by substrate models. When the contact depth was on the order of the coating thickness, the contact stiffness actually decreased. Additionally, the forceseparation plots showed that the Ru and Pt surfaces either accumulated large amounts of contamination or were less susceptible to being wiped clean than the Au film. Further, scratch testing of the Au film and Ru and Pt coatings show that the hard surface coatings reduce material removal and contact wear. Ultra-thin Ru and Pt surface coatings on Au films are shown to be improved material systems for ohmic contact switches. The wear is reduced for coated materials, while the resistance and power consumption through the coating are not significantly affected.
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.
A novel approach of high speed scratching on silicon wafers at nanoscale depths of cut
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
Using Robinhood to Manage Files on Peregrine | High-Performance Computing |
: $ 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
Urine-marking and ground-scratching by free-ranging Arctic Wolves, Canis lupus arctos, in summer
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.
[Comparison of anti-angiogenic effect in vitro between ranibizumab and bevacizumab].
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.
Optical and nanomechanical study of anti-scratch layers on polycarbonate lenses
NASA Astrophysics Data System (ADS)
Charitidis, C.; Laskarakis, A.; Kassavetis, S.; Gravalidis, C.; Logothetidis, S.
2004-07-01
In recent years, as the optical-electronic industry developed, polymeric materials were gradually increasing in importance. Polycarbonate (PC) is a good candidate for eyewear applications due to its low weight and transparency. In the case of PC lenses, the deposition of anti-scratch (AS) coatings on the polymer surface is essential for the improvement of the mechanical behavior of the lens. In this work, we present a detailed investigation of the optical and nanomechanical properties of a PC based optical lens and coated by an AS coating as a protective overcoat. The study of the effect of the AS coating on the optical response of the PC lens has been performed by the use of Spectroscopic Ellipsometry (SE) in the IR spectral region, where the characteristic features corresponding to the different bonding configuration of the PC lens and the AS coating were studied. Also, the nanomechanical study of the PC lens, before and after the deposition of the AS coating, performed by nanoindentation measurements revealed the significant enhancement of the mechanical response of the AS/PC lens. More specifically, the AS/PC lens is characterized by enhanced values of hardness and elastic modulus. Finally, the use of AS coating has found to lead to a better scratch resistance and to the reduction of the coefficient of friction (μ) of the PC lens.
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.
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.
Cat-scratch uveitis confirmed by histological, serological, and molecular diagnoses.
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.
Occupational protein contact dermatitis in food handlers.
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.
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.
Wang, Song; Wang, Fei; Liao, Zhenhua; Wang, Qingliang; Liu, Yuhong; Liu, Weiqiang
2015-10-01
A ball-on-socket contact configuration was designed to simulate an artificial cervical disk in structure. UHMWPE (ultra high molecular weight polyethylene) hot pressed by powders and Ti6Al4V alloy were selected as the material combination of ball and socket. The socket surface was coated by a ~500 nm C-DLC (carbon ion implantation-diamond like carbon) mixed layer to improve its surface nano hardness and wear resistance. The torsional fretting wear behavior of the ball-on-socket model was tested at different angular displacements under 25% bovine serum lubrication with an axial force of 100 N to obtain more realistic results with that in vivo. The fretting running regimes and wear damage characteristics as well as wear mechanisms for both ball and socket were studied based on 2D (two dimension) optical microscope, SEM (scanning electron microscope) and 3D (three dimension) profiles. With the increase of angular displacement amplitude from 1° to 7°, three types of T-θ (Torsional torque-angular displacement amplitude) curves (i.e., linear, elliptical and parallelogram loops) corresponding to running regimes of PSR (partial slip regime), MR (mixed regime) and SR (slip regime) were observed and analyzed. Both the central region and the edge zone of the ball and socket were damaged. The worn surfaces were characterized by wear scratches and wear debris. In addition, more severe wear damage and more wear debris appeared on the central region of the socket at higher angular displacement amplitude. The dominant damage mechanism was a mix of surface scratch, adhesive wear and abrasive wear for the UHMWPE ball while that for the coated socket was abrasive wear by PE particles and some polishing and rolling process on the raised overgrown DLC grains. The frictional kinetic behavior, wear type, damage region and damage mechanism for the ball-on-socket model revealed significant differences with those of a ball-on-flat contact while showing better consistency with that of in vitro cervical prosthesis simulations according to the literature. Copyright © 2015. Published by Elsevier B.V.
NASA Astrophysics Data System (ADS)
Kim, Jong-Woong; Lee, Da Hee; Jeon, Hee-Jeong; Jang, Sung Il; Cho, Hyun Min; Kim, Youngmin
2018-01-01
The recyclable silicone-based thermoset was successfully synthesized by making use of a Diels-Alder (DA) adduct as a cross-linker. The incorporation of the furan-tethered diol 1 into the polymer backbones realized the crosslinking of polymers via the DA reaction. The thermosetting polymer was dissolved in DMF after the retro DA reaction which was monitored by 1H NMR spectroscopy. Due to the retro DA reaction, polymer showed the mendable behavior when it was scratched followed by being heated. This polymer was mixed with alumina powders to fabricate the thermal pad. The thermal resistance of this pad was measured to be 0.48 K/W by a thermal transient test. The thermosetting composite was recycled via the retro DA reaction. The thermal resistance of the recycled one was similar to that of the original one.
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...
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…
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...
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…
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
1975-08-01
CONT’D) Nuniln 21 23 24 26 20 30 31 34 3 5 ■A 6 37 39 Title Page Nomarski Fnterference Microscopy of Surface of 61 Film Substrates Tes...Potassium Chloride Surfaces 83 Anomalous Indentation Behavior 85 Indentations in As.;S Films - Nomarski Microscopy 92 Indentations in As9S...minimum load required to remove the film. Nomarski interference microscopy was used to inspect the scratched surfaces. The method was found to be less
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.
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.
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…
An unusual outcome in a child with hepatosplenic cat-scratch disease.
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.
Identification and Development of Simple Acceptance Tests for MRE Film Pouch Materials
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
Scratch2 prevents cell cycle re-entry by repressing miR-25 in postmitotic primary neurons.
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.
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.
Rabies-related knowledge and practices among persons at risk of bat exposures in Thailand.
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.
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.
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.
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…
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…
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.
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.
Bone scintigraphy in children with cat scratch disease.
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.
Advanced Mitigation Process (AMP) for Improving Laser Damage Threshold of Fused Silica Optics
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
Effects of Low-Altitude Aircraft Overflights on Domestic Turkey Poults
1990-06-30
density rearing systems, too much heat, nutritional and mineral deficiencies, and irritation from parasites. If birds pick on one another or scratch...influence of flight noise on mortality and productivity in broiler chickens and in hen behavior," Inaugural Dissertation for Animal Hygiene at the...and were housed in two 2 x 6 m covered chicken wire pens at the experimental site (see Figure 2-4). Originally, they were to have been acclimatized
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.
Improved self-healing of polyethylene/carbon black nanocomposites by their shape memory effect.
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.
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.
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
Effects of a multicomponent exercise program in institutionalized elders with Alzheimer's disease.
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.
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
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.
A Study of relationship between frailty and physical performance in elderly women.
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.
Flexion Reflex Can Interrupt and Reset the Swimming Rhythm.
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.
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
Unclaimed Prize Information Biases Perceptions of Winning in Scratch Card Gambling.
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.
Epidemiologic and clinical aspects of animal bite injuries.
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.
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.
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.
Choi, Hyeongwon; Kim, Dong-Jin; Nam, Seungwoo; Lim, Sunki; Hwang, Jae-Sung; Park, Ki Sook; Hong, Hyun Sook; Won, Younsun; Shin, Min Kyung; Chung, Eunkyung; Son, Youngsook
2018-03-01
Atopic dermatitis (AD) is a chronic inflammatory skin disorder characterized by intense pruritus and eczematous lesion. Substance P (SP) is an 11-amino-acid endogenous neuropeptide that belongs to the tachykinin family and several reports recently have supported the anti-inflammatory and tissue repairing roles of SP. In this study, we investigated whether SP can improve AD symptoms, especially the impaired skin barrier function, in 2, 4, 6-trinitrochlorobenzene (TNCB)-induced chronic dermatitis of NC/Nga mice or not. AD-like dermatitis was induced in NC/Nga mice by repeated sensitization with TNCB for 5 weeks. The experimental group designations and topical treatments were as follows: vehicle group (AD-VE); SP group (AD-SP); and SP with NK1R antagonist CP99994 (AD-SP-A) group. Histological analysis was performed to evaluate epidermal differentiation, dermal integrity, and epidermal nerve innervation in AD-like lesions. The skin barrier functions and pruritus of NC/Nga mice were evaluated by measuring transepidermal water loss (TEWL) and scratching behavior, respectively. Topical SP treatment resulted in significant down-regulation of Ki67 and the abnormal-type keratins (K) K6, K16, and K17, restoration of filaggrin and claudin-1, marked reduction of TEWL, and restoration of basement membrane and dermal collagen deposition, even under continuous sensitization of low dose TNCB. In addition, SP significantly reduced innervation of itch-evoking nerve fibers, gelatinase activity and nerve growth factor (NGF) expression in the epidermis but upregulated semaphorin-3A (Sema3A) expression in the epidermis, along with reduced scratching behavior in TNCB-treated NC/Nga mice. All of these effects were completely reversed by co-treatment with the NK1R antagonist CP99994. In cultured human keratinocytes, SP treatment reduced expression of TGF-α, but upregulated TGF-β and Sema3A. Topically administered SP can restore normal skin barrier function, reduce epidermal infiltration of itch-evoking nerve fibers in the AD-like skin lesions, and alleviate scratching behavior. Thus, SP may be proposed as a potential medication for chronic dermatitis and AD. Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.
Jiang, Ju; Yamaguchi, Takuji; Funakushi, Naoko; Kuhara, Takatoshi; Fan, Ping-shen; Ueki, Rie; Suto, Hajime; Kase, Yoshio; Ikeda, Shigaku; Ogawa, Hideoki
2009-10-01
Increasing evidence suggests that stress can trigger and exacerbate atopic dermatitis (AD). Psychotherapy is becoming more important in the treatment of AD patients. Yokukansan (YKS, Yi-Gan San in Chinese), a traditional Japanese medicine, has been widely utilized in the treatment of neurosis, insomnia and anxiety especially in Asian countries. Furthermore, it was reported that YKS inhibited skin lesions in socially isolated mice but not in group-housed mice. Therefore, in the present study it was investigated whether or not YKS was effective in the treatment of AD using socially isolated NC/Nga mice. The present study was designed to assess the effect of YKS on the development of AD-like lesions in socially isolated NC/Nga mice to obtain information about its usefulness in the treatment of AD. Ten-week-old male NC/Nga mice were socially isolated under conventional conditions. YKS was administered orally to mice at the dose of 0.5% or 1.0% together with diet. The efficacy of YKS was evaluated by assessing skin lesion severity, scratching behaviors, skin hydration, and infiltration of inflammatory cells in the skin. Grooming behaviors evoked by social isolation stress and serum corticosterone levels were also measured. Oral administration of YKS to socially isolated NC/Nga mice resulted in the inhibition of exacerbation of AD-like skin lesions. It seemed that the inhibition of exacerbation of AD-like skin lesions observed in NC/Nga mice might be due to suppression of the scratching and grooming behaviors, inhibition of the infiltration of mast cells and eosinophils, and retention of humidity in the skin. Serum corticosterone levels were also significantly inhibited in the 1%-YKS-treated mice as compared with those of the control mice. There were no significant differences in the levels of serum total IgE and nerve growth factor (NGF) between the YKS-treated mice and the non-treated control mice. YKS inhibited the development of AD-like skin lesions in socially isolated NC/Nga mice by suppressing scratching and infiltration of inflammatory cells in the skin. These results indicate that YKS possesses an anti-itching property, and its anti-itching may be partly through attenuation on social isolation stress. It is expected that YKS might provide an effective alternative therapy for AD in human patients.
Wallace, Emma K; Kingston-Jones, Mark; Ford, Matthew; Semple, Stuart
2013-01-01
The use of music as enrichment has rarely been explored in zoos, despite evidence that music has a positive effect on a range of laboratory housed animals. In this study of moloch gibbons, Hylobates moloch, at Howletts Wild Animal Park (Kent, England), instrumental classical music was played to eight individuals in two family groups. Music was played 7 hr a day during three of six study weeks for each group, alternating with control weeks in which no music was played. In focal watches, data were recorded on a measure of activity, brachiation, and on two rates of affiliative behavior, giving and receiving grooming. In addition, to assess potential impacts on emotional state, data were recorded on self-scratching and self-grooming, two widely used indices of anxiety or stress. Analyses were carried out for each individual separately, as previous studies of primates indicate animals may differ in their response to enrichment. Results revealed little evidence for effects of music on gibbons' behavior. During the music compared to control weeks, the adult male from one group showed higher rates of self-scratching and higher durations of both self-grooming and grooming others. The adult female from the same group was groomed more during the music weeks than control weeks. For the six other animals, no significant differences in behaviors were seen between music and control conditions. Our findings suggest music may not be an effective enrichment for captive gibbons, and further highlight the importance of considering individual differences when assessing the effects of potential enrichment. Copyright © 2013 Wiley Periodicals Inc.
Inhaled oxytocin increases positive social behaviors in newborn macaques
Simpson, Elizabeth A.; Sclafani, Valentina; Paukner, Annika; Hamel, Amanda F.; Novak, Melinda A.; Meyer, Jerrold S.; Suomi, Stephen J.; Ferrari, Pier Francesco
2014-01-01
Early caregiver–infant interactions are critical for infants’ socioemotional and cognitive development. Several hormones and neuromodulators, including oxytocin, affect these interactions. Exogenous oxytocin promotes social behaviors in several species, including human and nonhuman primates. Although exogenous oxytocin increases social function in adults—including expression recognition and affiliation—it is unknown whether oxytocin can increase social interactions in infants. We hypothesized that nebulized oxytocin would increase affiliative social behaviors and such effects would be modulated by infants’ social skills, measured earlier in development. We also hypothesized that oxytocin’s effects on social behaviors may be due to its anxiolytic effects. We tested these hypotheses in a blind study by nebulizing 7- to 14-d-old macaques (n = 28) with oxytocin or saline. Following oxytocin administration, infants’ facial gesturing at a human caregiver increased, and infants’ salivary oxytocin was positively correlated with the time spent in close proximity to a caregiver. Infants’ imitative skill (measured earlier in development: 1–7 d of age) predicted oxytocin-associated increases in affiliative behaviors—lip smacking, visual attention to a caregiver, and time in close proximity to a caregiver—suggesting that infants with higher propensities for positive social interactions are more sensitive to exogenous oxytocin. Oxytocin also decreased salivary cortisol, but not stress-related behaviors (e.g., scratching), suggesting the possibility of some anxiolytic effects. To our knowledge, this study provides the first evidence that oxytocin increases positive social behaviors in newborns. This information is of critical importance for potential interventions aimed at ameliorating inadequate social behaviors in infants with higher likelihood of developing neurodevelopmental disorder. PMID:24778211
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…
Human bubonic plague transmitted by a domestic cat scratch.
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.
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…
Establishment of a cell-based wound healing assay for bio-relevant testing of wound therapeutics.
Planz, Viktoria; Wang, Jing; Windbergs, Maike
Predictive in vitro testing of novel wound therapeutics requires adequate cell-based bio-assays. Such assays represent an integral part during preclinical development as pre-step before entering in vivo studies. Simple "scratch tests" based on defected skin cell monolayers exist, however these can solely be used for testing liquids, as cell monolayer destruction and excessive hydration limit their applicability for (semi-)solid systems like wound dressings. In this context, a cell-based wound healing assay is introduced for rapid and predictive testing of wound therapeutics independent of their physical state in a bio-relevant environment. A novel wound healing assay was established for bio-relevant and predictive testing of (semi-) solid wound therapeutics. The assay allows for physiologically relevant hydration of the tested wound therapeutics at the air-liquid interface and their removal without cell monolayer disruption. In a proof-of-concept study, the applicability and discriminative power could be demonstrated by examining unloaded and drug-loaded wound dressings with two different established wound healing actives (dexpanthenol and metyrapone) and their effect on skin cell behavior. The influence of the released drug on the cells´ healing behavior could successfully be monitored over time. Wound size assessment after 96h resulted in an eight fold smaller wound area for drug treated models compared to the ones treated with unloaded fibers and non-treated wounds. This assay provides valuable first insights towards the establishment of a valid screening and evaluation tool for preclinical wound therapeutic development from liquid to (semi-)solid systems to improve predictability in a simple, yet standardized way. Copyright © 2017 Elsevier Inc. All rights reserved.
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
Che, Denis Nchang; Cho, Byoung Ok; Shin, Jae Young; Kang, Hyun Ju; Kim, Young-Soo; Jang, Seon Il
2018-05-15
Interleukin-31 (IL-31) is a recently discovered cytokine that is tightly linked to the pathogenesis of pruritus seen in atopic dermatitis. Flavonoids, like fisetin, are naturally occurring molecules with antioxidant, cytoprotective, and anti-inflammatory actions. the present study sought to investigate whether fisetin modulates IL-31 and histamine release in human mast cells (HMC-1). HMC-1 cells were pretreated with fisetin at various doses and stimulated with phorbol-12-myristate 13-acetate and calcium ionophore A23187 (PI) for different time intervals. We evaluated IL-31 production and histamine release and signaling mechanism of the action of fisetin on IL-31 production. We also investigated the effects of fisetin on scratching behaviors in mice. Fisetin decreased PI-stimulated mRNA expression and production of IL-31 in HMC-1 cells. Fisetin inhibited PI-induced phosphorylation of mitogen-activated protein kinases that further suppressed nuclear factor (NF-κB) activation and translocation to the nucleus through the inhibition of IκB-α phosphorylation. Fisetin also prevented mast cell release of histamine in HMC-1 cells. Mice in-vivo studies show that fisetin reduced scratching behaviors in mice. These pharmacological actions of fisetin provide new suggestions that fisetin can be of potential use for the treatment of pruritus that cannot be treated with histamine receptor blockers alone. Copyright © 2018 Elsevier Inc. All rights reserved.
Yamaura, Katsunori; Tomono, Ayana; Suwa, Eriko; Ueno, Koichi
2013-01-01
Royal jelly is widely used as a health tonic, especially in Asia. Royal jelly is commonly used in cosmetics as well as in dietary supplements and beverages. Little is known, however, about the pharmacologic efficacy of topical royal jelly. Therefore, we investigated the antipruritic activity of topical royal jelly on chronic pruritus in experimental allergic contact dermatitis in mice. HAIRLESS MICE (HOS: HR-1), with chronic allergic contact dermatitis induced by 5 weeks of repeated application of 2,4,6-trinitro-1-chlorobenzene (TNCB) to the entire back skin were treated topically with royal jelly (0.01% or 1%) for 5 weeks after sensitization with TNCB. The effects of royal jelly on pruritus and inflammation were evaluated by measurement of scratching behavior and skin inflammation score, respectively. Repeated application of TNCB to the back skin of mice elicited frequent scratching behavior immediately and 24h after challenge. Topical royal jelly (0.01% or 1%) and betamethasone (0.01%) significantly ameliorated this chronic pruritus throughout the experimental period. The level of nerve growth factor mRNA in back skin was increased in the mice with dermatitis and reduced by betamethasone, but not by royal jelly. The inhibitory effect of royal jelly on chronic pruritus may occur through different mechanisms from those of betamethasone. Topical application of royal jelly, as used in cosmetics, might be beneficial for the alleviation of chronic pruritus.
Ok, Seon; Oh, Sa-Rang; Jung, Tae-Sung; Jeon, Sang-Ok; Jung, Ji-wook
2018-01-01
We investigated the cellular and molecular mechanisms mediating the effects of Angelica gigas Nakai extract (AGNE) through the mitogen-activated protein kinases (MAPKs)/NF-κB pathway using in vitro and in vivo atopic dermatitis (AD) models. We examined the effects of AGNE on the expression of proinflammatory cytokines and chemokines in human mast cell line-1 (HMC-1) cells. Compound 48/80-induced pruritus and 2,4-dinitrochlorobenzene- (DNCB-) induced AD-like skin lesion mouse models were also used to investigate the antiallergic effects of AGNE. AGNE reduced histamine secretion, production of proinflammatory cytokines including interleukin- (IL-) 1β, IL-4, IL-6, IL-8, and IL-10, and expression of cyclooxygenase- (COX-) 2 in HMC-1 cells. Scratching behavior and DNCB-induced AD-like skin lesions were also attenuated by AGNE administration through the reduction of serum IgE, histamine, tumor necrosis factor-α (TNF-α), IL-6 levels, and COX-2 expression in skin tissue from mouse models. Furthermore, these inhibitory effects were mediated by the blockade of the MAPKs and NF-κB pathway. The findings of this study proved that AGNE improves the scratching behavior and atopy symptoms and reduces the activity of various atopy-related mediators in HMC-1 cells and mice model. These results suggest the AGNE has a therapeutic potential in anti-AD. PMID:29713361
[Eye and cat scratch disease: A case series].
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.
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.
General Halleck's itchy elbows.
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.
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
Scratched: World War II Airborne Operations That Never Happened
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
Monitoring of atopic dermatitis using leaky coaxial cable.
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.
Monitoring of atopic dermatitis using leaky coaxial cable
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
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%.
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
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.
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
Characterizing Sintered Nano-Hydroxyapatite Sol-Gel Coating Deposited on a Biomedical Ti-Zr-Nb Alloy
NASA Astrophysics Data System (ADS)
Jafari, Hassan; Hessam, Hamid; Shahri, Seyed Morteza Ghaffari; Assadian, Mahtab; Shairazifard, Shahin Hamtaie Pour; Idris, Mohd Hasbullah
2016-03-01
In this study, sol-gel dip-coating method was used to coat nano-hydroxyapatite on specimens of Ti-14Zr-13Nb alloy for orthopedic applications. The coated specimens were sintered at three different temperatures and time spans to evaluate the impact of sintering process on microstructure, mechanical, bio-corrosion, and bioactivity properties of the coating. Field-emission scanning electron microscopy and x-ray diffraction were used to analyze the coating microstructure. Coating adhesion and mechanical performance were also investigated by scratch testing. Besides, electrochemical corrosion and immersion tests were performed in simulated body fluid to examine the sintering effect on corrosion performance and bioactivity of the coatings, respectively. The evaluations of coated specimens displayed that sintering at elevated temperatures leads to higher surface integrity and improves crystallinity of the nano-hydroxyapatite to approximately 89% which brings about distinctively enhanced mechanical properties. Similarly, it improved the corrosion rate for about 17 times through sintering at 700 °C. Immersion test proved that the coating increased the bioactivity resulted from the dissolution of calcium phosphates into the corresponding environment. It is noticeable that sintering the dip-coated specimens in the nano-hydroxyapatite improves corrosion performance and maintains bioactive behaviors as well.
NASA Technical Reports Server (NTRS)
Chang, L.; Hall, P. B.; Thom, R.
1996-01-01
This research reports on an experimental study of the effects of materials and surface roughness on the scuffing characteristics of rolling/sliding contacts cooled and lubricated with liquid oxygen. Experiments were carried out under heavy loading with a Hertzian pressure in the range of 2.0 GPa to 3.0 GPa and with a high rolling velocity of up to 48 m/s. For contacts between AISI 440 C stainless-steel elements, the results showed that the scuffing behavior of the system was fairly consistent under a wide range of rolling velocity. Scuffing commenced at a small slide-to-roll ratio of around 0.02, and the scuffing behavior of the contact was not sensitive to surface roughness for the test-sample RMS roughness ranging from 0.02 microns to 0.10 microns. For contacts between 440 C and Si3N4 elements, on the other hand, the scuffing behavior of the system was not very consistent and somewhat unpredictable. The results were sensitive to surface roughness particularly that of the Si3N4 test sample. With well polished test samples, consistent results were obtained; the level of traction was lower than that with a 440 C toroid and scuffing did not take place up to a slide-to-roll ratio of near 0.03. The results strongly suggest that significant hydrodynamic effect can be generated by liquid oxygen under heavy loading and high velocity conditions. The results also suggest that the hydrodynamic action is likely generated by the conventional viscous mechanism as it can be largely destroyed by a narrow circumferential surface scratch running through the central region of the contact.
Active learning reduces annotation time for clinical concept extraction.
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.
A Study and Review of Effects of Botulinum Toxins on Mast Cell Dependent and Independent Pruritus
Ramachandran, Roshni; Marino, Marc J.; Paul, Snighdha; Wang, Zhenping; Mascarenhas, Nicholas L.; Pellett, Sabine; Johnson, Eric A.; DiNardo, Anna; Yaksh, Tony L.
2018-01-01
Pruriceptive itch originates following activation of peripheral sensory nerve terminals when pruritogens come in contact with the skin. The ability of botulinum neurotoxins (BoNTs) to attenuate transmitter release from afferent terminals provides a rationale for studying its effect on pruritus. This study investigated the effects of BoNT/A1 and BoNT/B1 on mast cell dependent (Compound 48/80:48/80) and independent (Chloroquine:CQ) scratching. C57Bl/6 male mice received intradermal injection of 1.5 U of BoNT/A1, BoNT/B1 or saline 2, 7, 14 and 21 days prior to ipsilateral 48/80 or CQ at the nape of the neck. Ipsilateral hind paw scratching was determined using an automated recording device. The effect of BoNTs on 48/80 mediated mast cell degranulation was analyzed in human and murine mast cells and the presence of SNAREs was determined using qPCR, immunostaining and Western blot. Pre-treatment with BoNT/A1 and BoNT/B1 reduced 48/80 and CQ induced scratching behavior starting on day 2 with reversal by day 21. Both serotypes inhibited 48/80 induced mast cell degranulation. qPCR and immunostaining detected SNAP-25 mRNA and protein, respectively, in mast cells, however, Western blots did not. This study demonstrates the long-lasting anti-pruritic effects of two BoNT serotypes, in a murine pruritus model using two different mechanistically driven pruritogens. These data also indicate that BoNTs may have a direct effect upon mast cell degranulation. PMID:29570628
A Study and Review of Effects of Botulinum Toxins on Mast Cell Dependent and Independent Pruritus.
Ramachandran, Roshni; Marino, Marc J; Paul, Snighdha; Wang, Zhenping; Mascarenhas, Nicholas L; Pellett, Sabine; Johnson, Eric A; DiNardo, Anna; Yaksh, Tony L
2018-03-23
Pruriceptive itch originates following activation of peripheral sensory nerve terminals when pruritogens come in contact with the skin. The ability of botulinum neurotoxins (BoNTs) to attenuate transmitter release from afferent terminals provides a rationale for studying its effect on pruritus. This study investigated the effects of BoNT/A1 and BoNT/B1 on mast cell dependent (Compound 48/80:48/80) and independent (Chloroquine:CQ) scratching. C57Bl/6 male mice received intradermal injection of 1.5 U of BoNT/A1, BoNT/B1 or saline 2, 7, 14 and 21 days prior to ipsilateral 48/80 or CQ at the nape of the neck. Ipsilateral hind paw scratching was determined using an automated recording device. The effect of BoNTs on 48/80 mediated mast cell degranulation was analyzed in human and murine mast cells and the presence of SNAREs was determined using qPCR, immunostaining and Western blot. Pre-treatment with BoNT/A1 and BoNT/B1 reduced 48/80 and CQ induced scratching behavior starting on day 2 with reversal by day 21. Both serotypes inhibited 48/80 induced mast cell degranulation. qPCR and immunostaining detected SNAP-25 mRNA and protein, respectively, in mast cells, however, Western blots did not. This study demonstrates the long-lasting anti-pruritic effects of two BoNT serotypes, in a murine pruritus model using two different mechanistically driven pruritogens. These data also indicate that BoNTs may have a direct effect upon mast cell degranulation.
A Study of relationship between frailty and physical performance in elderly women
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
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schmutz, P.; Frankel, G.S.
1998-07-01
The localized corrosion of AA2024-T3, and the behavior of intermetallic particles in particular, were studied using different capabilities of the atomic force microscope (AFM). The role of intermetallic particles in determining the locations and rates of localized corrosion was determined using scanning Kelvin probe force microscopy in air after exposure to chloride solutions. Al-Cu-Mg particles, which have a noble Volta potential in air because of an altered surface film, are actively dissolved in chloride solution after a certain induction time. Al-Cu(Fe, Mn) particles are heterogeneous in nature and exhibit nonuniform dissolution in chloride solution as well as trenching of themore » matrix around the particles. Light scratching of the surface by rastering with the AFM tip in contact mode in chloride solution results in accelerated dissolution of both pure Al and alloy 2024-T3. The abrasion associated with contact AFM in situ resulted in the immediate dissolution of the Al-Cu-Mg particles because of a destabilization of the surface film.« less
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.
Comparison of mechanical behavior of TiN, TiNC, CrN/TiNC, TiN/TiNC films on 9Cr18 steel by PVD
NASA Astrophysics Data System (ADS)
Feng, Xingguo; Zhang, Yanshuai; Hu, Hanjun; Zheng, Yugang; Zhang, Kaifeng; Zhou, Hui
2017-11-01
TiN, TiNC, CrN/TiNC and TiN/TiNC films were deposited on 9Cr18 steel using magnetron sputtering technique. The morphology, composition, chemical state and crystalline structure of the films were observed and analyzed by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Hardness and adhesion force were tested by nanoindentation and scratch tester, respectively. The friction and wear behavior of TiN, TiNC, CrN/TiNC and TiN/TiNC films sliding against GCr15 balls were investigated and compared synthetically using ball-on-disk tribometer. It was found that Tisbnd N, Tisbnd C, Tisbnd Nsbnd C and Csbnd C bonds were formed. The TiN/TiNC film was composed of TiN, TiC and TiNC phases. Hardness and adhesion force results indicated that although the TiN film possessed the highest hardness, its adhesion force was lowest among all the films. Tribological test results showed that the friction coefficient of TiN/TiNC was much lower than that of TiN and the wear rate decreases remarkably from 2.3 × 10-15 m3/Nm to 7.1 × 10-16 m3/Nm, which indicated the TiN/TiNC film has better wear resistance.
Corrosion behavior and mechanical properties of bioactive sol-gel coatings on titanium implants.
Catauro, M; Bollino, F; Papale, F; Giovanardi, R; Veronesi, P
2014-10-01
Organic-inorganic hybrid coatings based on zirconia and poly (ε-caprolactone) (PCL) were prepared by means of sol-gel dip-coating technique and used to coat titanium grade 4 implants (Ti-4) in order to improve their wear and corrosion resistance. The coating chemical composition has been analysed by ATR-FTIR. The influence of the PCL amount has been investigated on the microstructure, mechanical properties of the coatings and their ability to inhibit the corrosion of titanium. SEM analysis has shown that all coatings have a nanostructured nature and that the films with high PCL content are crack-free. Mechanical properties of the coatings have been studied using scratch and nano-indentation tests. The results have shown that the Young's modulus of the coatings decreases in presence of large amounts of the organic phase, and that PCL content affects also the adhesion of the coatings to the underlying Ti-4 substrate. However, the presence of cracks on the PCL-free coatings affects severely the mechanical response of the samples at high loads. The electrochemical behavior and corrosion resistance of the coated and uncoated substrate has been investigated by polarization tests. The results have shown that both the coatings with or without PCL don't affect significantly the already excellent passivation properties of titanium. Copyright © 2014. Published by Elsevier B.V.
Widowski, T M; Caston, L J; Casey-Trott, T M; Hunniford, M E
2017-09-01
Standards for feeder (a.k.a. feed trough) space allowance (SA) are based primarily on studies in conventional cages where laying hens tend to eat simultaneously, limiting feeder space. Large furnished cages (FC) offer more total space and opportunities to perform a greater variety of behaviors, which may affect feeding behavior and feeder space requirements. Our objective was to determine the effects of floor/feeder SA on behavior at the feeder. LSL-Lite hens were housed in FC equipped with a nest, perches, and a scratch mat. Hens with SA of either 520 cm2 (Low; 8.9 cm feeder space/hen) or 748 cm2 (High; 12.8 cm feeder space/hen) per bird resulted in groups of 40 vs. 28 birds in small FC (SFC) and 80 vs. 55 in large FC (LFC). Chain feeders ran at 0500, 0800, 1100, 1400, and 1700 with lights on at 0500 and off at 1900 hours. Digital recordings of FC were scanned at chain feeder onset and every 15 min for one h after (5 scans × 5 feeding times × 2 d) to count the number of birds with their head in the feeder. All occurrences of aggressive pecks and displacements during 2 continuous 30-minute observations at 0800 h and 1700 h also were counted. Mixed model repeated analyses tested the effects of SA, cage size, and time on the percent of hens feeding, and the frequency of aggressive pecks and displacements. Surprisingly, the percent of birds feeding simultaneously was similar regardless of cage size (LFC: 23.0 ± 0.9%; SFC: 24.0 ± 1.0%; P = 0.44) or SA (Low: 23.8 ± 0.9%; High: 23.3 ± 1.0%; P = 0.62). More birds were observed feeding at 1700 h (35.3 ± 0.1%) than any at other time (P < 0.001). Feeder use differed by cage area (nest, middle, or scratch) over the d (P < 0.001). The frequency of aggressive pecks was low overall and not affected by SA or cage size. Frequency of displacements was also low but greater at Low SA (P = 0.001). There was little evidence of feeder competition at the Low SA in this study. © The Author 2017. Published by Oxford University Press on behalf of Poultry Science Association.
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.
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 .
Cat scratches, not bites, are associated with unipolar depression--cross-sectional study.
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.
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.
Cat-scratch disease: unusual perivascular chorioretinal lesions.
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.
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.
Robust automatic line scratch detection in films.
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.
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.
Noxious heat and scratching decrease histamine-induced itch and skin blood flow.
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.
Rabies-Related Knowledge and Practices Among Persons At Risk of Bat Exposures in Thailand
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
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
NASA Astrophysics Data System (ADS)
Wei, Dongbo; Zhang, Pingze; Liu, Yingchao; Chen, Xiaohu; Ding, Feng; Li, Fengkun
2018-02-01
The Zr coating and Zr-Er coating are grown on TC11 substrate by double-glow plasma surface metallurgy technique, followed by the wear tests at ambient temperature and 500 °C. The data of nanohardness and elastic modulus of the samples are collected by the nano-indentation test. The adhesion strength of coatings is investigated by means of the scratch test. The study of wear resistance is performed using a ball-on-disc wear test system by running against the Si3N4 ball and measured by scanning electron microscope (SEM) and X-ray diffraction (XRD). Experimental results indicate that the nanohardness of the Zr coating and Zr-Er coating are 5.94 GPa and 7.98 GPa, respectively, which are 1.79 times and 2.41 times greater than that of TC11 substrate. Zr coating and Zr-Er coating realize the metallurgical bonding with TC11 substrate with continuous and compact structure. Compared with the Zr coating and TC11, the Zr-Er coating presents the lowest specific wear rates, which are 1.689 × 10-6 mm3 Nm-1 and 1.851 × 10-6 mm3 Nm-1 at ambient temperature and 500 °C respectively, indicating the excellent and improved wear resistance of TC11.
Cat scratch disease in an immunosuppressed patient with systemic lupus erythematosus.
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.
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…
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.
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.
Topical royal jelly alleviates symptoms of pruritus in a murine model of allergic contact dermatitis
Yamaura, Katsunori; Tomono, Ayana; Suwa, Eriko; Ueno, Koichi
2013-01-01
Background: Royal jelly is widely used as a health tonic, especially in Asia. Royal jelly is commonly used in cosmetics as well as in dietary supplements and beverages. Little is known, however, about the pharmacologic efficacy of topical royal jelly. Therefore, we investigated the antipruritic activity of topical royal jelly on chronic pruritus in experimental allergic contact dermatitis in mice. Materials and Methods: Hairless mice (HOS: HR-1), with chronic allergic contact dermatitis induced by 5 weeks of repeated application of 2,4,6-trinitro-1-chlorobenzene (TNCB) to the entire back skin were treated topically with royal jelly (0.01% or 1%) for 5 weeks after sensitization with TNCB. The effects of royal jelly on pruritus and inflammation were evaluated by measurement of scratching behavior and skin inflammation score, respectively. Results: Repeated application of TNCB to the back skin of mice elicited frequent scratching behavior immediately and 24h after challenge. Topical royal jelly (0.01% or 1%) and betamethasone (0.01%) significantly ameliorated this chronic pruritus throughout the experimental period. The level of nerve growth factor mRNA in back skin was increased in the mice with dermatitis and reduced by betamethasone, but not by royal jelly. Conclusion: The inhibitory effect of royal jelly on chronic pruritus may occur through different mechanisms from those of betamethasone. Topical application of royal jelly, as used in cosmetics, might be beneficial for the alleviation of chronic pruritus. PMID:23661987
A star in the eye: cat scratch neuroretinitis.
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.
... 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 ...
Friction Anisotropy with Respect to Topographic Orientation
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
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.
Mechanical comparison of a polymer nanocomposite to a ceramic thin-film anti-reflective filter.
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.
NASA Astrophysics Data System (ADS)
Wang, Zining; Li, Jia; Fang, QiHong; Liu, Bin; Zhang, Liangchi
2017-09-01
The mechanical behaviors and deformation mechanisms of scratched AlCrCuFeNi high entropy alloys (HEAs) have been studied by molecular dynamics (MD) simulations, in terms of the scratching forces, atomic strain, atomic displacement, microstructural evolution and dislocation density. The results show that the larger tangential and normal forces and higher friction coefficient take place in AlCrCuFeNi HEA due to its outstanding strength and hardness, and high adhesion and fracture toughness over the pure metal materials. Moreover, the stacking fault energy (SFE) in HEA increases the probability to initiate dislocation and twinning, which is conducive to the formation of complex deformation modes. Compared to the single element metal workpieces, the segregation potency of solutes into twinning boundary (TB) is raised due to the decreasing segregation energy of TB, resulting in the stronger solute effects on improving twinning properties for HEA workpiece. The higher dislocation density and the more activated slipping planes lead to the outstanding plasticity of AlCrCuFeNi HEA. The solute atoms as barriers to hinder the motion of dislocation and the severe lattice distortion to suppress the free slipping of dislocation are significantly stronger obstacles to strengthen HEA. The excellent comprehensive scratching properties of the bulk AlCrCuFeNi HEAs are associated with the combined effects of multiple strengthening mechanisms, such as dislocation strengthening, deformation twinning strengthening as well as solute strengthening. This work provides a basis for further understanding and tailoring SFE in mechanical properties and deformation mechanism of HEAs, which maybe facilitate the design and preparation of new HEAs with high performance.
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.
Physical and Neuropsychiatric Trauma-Wound Healing and Tissue Preservation
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
NASA Astrophysics Data System (ADS)
Canto, C. E.; Andrade, E.; Rocha, M. F.; Alemón, B.; Flores, M.
2017-09-01
The tribocorrosion resistance and adherence of multilayer coatings of TiAlPtN/TiAlN/TiAl synthesized by PVD reactive magnetron sputtering over a CoCrMo alloy substrate in 10 periods of 30 min each were analyzed and compared to those of the substrate alone and to that of a TiAlPtN single layer coating of the same thickness. The objective of the present work was to create multilayers with different amounts of Pt in order to enhance the tribocorrosion resistance of a biomedical alloy of CoCrMo. Tribocorrosion tests were performed using Simulated Body Fluid (SBF) at typical body temperature with a tribometer in a pin on disk test. The elemental composition and thickness of the coating which behave better at the tribocorrosion tests were evaluated by means of RBS (Rutherford Backscattering Spectroscopy) IBA (Ion Beam Analysis) technique, using an alpha particles beam of 1.8 MeV, before and after the reciprocating motion in the tribocorrosion test. In order to simulate the elemental profile of the samples, the SIMNRA simulation computer code was used. Measurements of the adhesion of the coatings to the substrate were carried on by means of a scratch test using a tribometer. By taking micrographs of the produced tracks, the critical loads at which the coatings are fully separated from the substrate were determined. From these tests it was observed that a coating with 10 min of TiAlPtN in a TiAlPtN/TiAl period of 30 min in multilayers of 10 periods and with an average thickness of 145 nm for the TiAlPtN nanolayers had the best tribocorrosion resistance behavior, compared to that of the CoCrMo alloy. The RBS experiments showed a reduction of the thickness of the films along with some loss of the multilayer structure after the reciprocating motion. The adhesion tests indicated that the multilayer with the average TiAlPtN thickness of 145 nm displayed the highest critical load. These results indicate a high correlation between the adherence and the tribocorrosion behavior.
Wear at the Implant-Abutment Interface of Zirconia Abutments Manufactured by Three CAD/CAM Systems.
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.
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.
NASA Astrophysics Data System (ADS)
Costa, R. P. C.; Lima-Oliveira, D. A.; Marciano, F. R.; Lobo, A. O.; Corat, E. J.; Trava-Airoldi, V. J.
2013-11-01
This paper reports the influence of the adhesion interlayer between stainless steel and diamond-like carbon (DLC) films in two different contact conditions: in dry air and deionized water. The water was the liquid used to understand the mechanism and chemical reactions of the tribolayer formation under boundary lubrication. The effect of silicon and carbonitride adhesion interlayer was investigated on uncoated and coated DLC films. The results show that DLC/DLC pairs using carbonitride in air (30% RH) showed 60% less friction coefficient and wear less than three orders of magnitude than DLC/DLC pairs using silicon as interlayer. In deionized water, DLC/DLC pairs using carbonitride as interlayer showed 31% less friction coefficient when compared to DLC/DLC pairs with silicon. Raman related the chemical and structural changes in the DLC films during sliding in air and in the presence of water. Scratch tests showed a critical load of 14 N and 33 N in DLC films with silicon and carbonitride, respectively.
... 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 ...
Song, Li; Wang, Shuxing; Zuo, Yunxia; Chen, Lucy; Martyn, Jeevendra A.; Mao, Jianren
2014-01-01
Midazolam and morphine are often used in pediatric intensive care unit (ICU) for analgesia and sedation. However, how these two drugs interact behaviorally remains unclear. Here, we examined whether 1) co-administration of midazolam with morphine would exacerbate morphine tolerance and morphine-induced hyperactive behaviors, and 2) protein kinase C (PKC) would contribute to these behavioral changes. Male rats of 3 to 4 weeks old were exposed to a hindpaw burn injury. In Experiment 1, burn-injured young rats received once daily saline or morphine (10 mg/kg, subcutaneous, s.c.), followed 30 min later by either saline or midazolam (2 mg/kg, intraperitoneal, i.p.), for 14 days beginning 3 days after burn injury. In Experiment 2, young rats with burn injury were administered with morphine (10 mg/kg, s.c.), midazolam (2 mg/kg, i.p.), and chelerythrine chloride (a non-specific PKC inhibitor 10 nmol, intrathecal) for 14 days. For both experiments, cumulative morphine anti-nociceptive dose-response (ED50) was tested and hyperactive behaviors such as jumping and scratching were recorded. Following 2 weeks of each treatment, ED50 dose was significantly increased in rats receiving morphine alone as compared with rats receiving saline or midazolam alone. The ED50 dose was further increased in rats receiving both morphine and midazolam. Co-administration of morphine and midazolam also exacerbated morphine-induced hyperactive behaviors. Expression of the NR1 subunit of the N-methyl-D-aspartate (NMDA) receptor and PKCγ in the spinal cord dorsal horn (immunohistochemistry; Western blot) was upregulated in burn-injured young rats receiving morphine alone or in combination with midazolam, and chelerythrine prevented the development of morphine tolerance. These results indicate that midazolam exacerbated morphine tolerance through a spinal NMDA/PKC-mediated mechanism. PMID:24713351
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.
Study of Mechano-Chemical Machining of Ceramics and the Effect on Thin Film Behavior.
1983-01-01
with Fe2O3 Under Various Pressures 9 7 Nomarski Micrographs of an Si N Substrate (a) Before *. and (b) After Mechanochemical Polishing 11 8 -Surface...the entire polished surface did not reveal any scratches. Figure 7 com- pares the Nomarski micrographs of an Si3 N4 substrate before (in the as...mechanochemically polished Si3N4 substrates, using an interferometric technique. The surface figure of a 2.5 x 2.5 cm Si 3N4 substrate is shown in Figure 9. This fig
Caccavale, Justin; Fiumara, David; Stapf, Michael; Sweitzer, Liedeke; Anderson, Hannah J; Gorky, Jonathan; Dhurjati, Prasad; Galileo, Deni S
2017-12-11
Glioblastoma multiforme (GBM) is a devastating brain cancer for which there is no known cure. Its malignancy is due to rapid cell division along with high motility and invasiveness of cells into the brain tissue. Simple 2-dimensional laboratory assays (e.g., a scratch assay) commonly are used to measure the effects of various experimental perturbations, such as treatment with chemical inhibitors. Several mathematical models have been developed to aid the understanding of the motile behavior and proliferation of GBM cells. However, many are mathematically complicated, look at multiple interdependent phenomena, and/or use modeling software not freely available to the research community. These attributes make the adoption of models and simulations of even simple 2-dimensional cell behavior an uncommon practice by cancer cell biologists. Herein, we developed an accurate, yet simple, rule-based modeling framework to describe the in vitro behavior of GBM cells that are stimulated by the L1CAM protein using freely available NetLogo software. In our model L1CAM is released by cells to act through two cell surface receptors and a point of signaling convergence to increase cell motility and proliferation. A simple graphical interface is provided so that changes can be made easily to several parameters controlling cell behavior, and behavior of the cells is viewed both pictorially and with dedicated graphs. We fully describe the hierarchical rule-based modeling framework, show simulation results under several settings, describe the accuracy compared to experimental data, and discuss the potential usefulness for predicting future experimental outcomes and for use as a teaching tool for cell biology students. It is concluded that this simple modeling framework and its simulations accurately reflect much of the GBM cell motility behavior observed experimentally in vitro in the laboratory. Our framework can be modified easily to suit the needs of investigators interested in other similar intrinsic or extrinsic stimuli that influence cancer or other cell behavior. This modeling framework of a commonly used experimental motility assay (scratch assay) should be useful to both researchers of cell motility and students in a cell biology teaching laboratory.
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.
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.
NASA Astrophysics Data System (ADS)
Menezes, Pradeep L.; Kishore; Kailas, Satish V.; Lovell, Michael R.
2015-01-01
Surface texture influences friction during sliding contact conditions. In the present investigation, the effect of surface texture and roughness of softer and harder counter materials on friction during sliding was analyzed using an inclined scratch testing system. In the experiments, two test configurations, namely (a) steel balls against aluminum alloy flats of different surface textures and (b) aluminum alloy pins against steel flats of different surface textures, are utilized. The surface textures were classified into unidirectionally ground, 8-ground, and randomly polished. For a given texture, the roughness of the flat surfaces was varied using grinding or polishing methods. Optical profilometer and scanning electron microscope were used to characterize the contact surfaces before and after the experiments. Experimental results showed that the surface textures of both harder and softer materials are important in controlling the frictional behavior. The softer material surface textures showed larger variations in friction between ground and polished surfaces. However, the harder material surface textures demonstrated a better control over friction among the ground surfaces. Although the effect of roughness on friction was less significant when compared to textures, the harder material roughness showed better correlations when compared to the softer material roughness.
Kinetic Investigation and Wear Properties of Fe2B Layers on AISI 12L14 Steel
NASA Astrophysics Data System (ADS)
Keddam, M.; Ortiz-Dominguez, M.; Elias-Espinosa, M.; Arenas-Flores, A.; Zuno-Silva, J.; Zamarripa-Zepeda, D.; Gomez-Vargas, O. A.
2018-03-01
In the current study, the powder-pack boriding was applied to the AISI 12L14 steel in the temperature range 1123 K to 1273 K for an exposure time between 2 and 8 hours. The produced boride layer was composed of Fe2B with a sawtooth morphology. A diffusion model based on the integral method was applied to investigate the growth kinetics of Fe2B layers. As a main result, the boron diffusion coefficients in Fe2B were estimated by considering the principle of mass balance at the (Fe2B/substrate) interface with an inclusion of boride incubation times. The value of activation energy for boron diffusion in AISI 12L14 steel was estimated as 165 kJ mol-1 and compared with other values of activation energy found in the literature. An experimental validation of the present model was made by using four different boriding conditions. Furthermore, the Rockwell-C adhesion test was employed to assess the cohesion of boride layers to the base metal. The scratch and pin-on-disc tests were also carried out to analyze the effect of boriding on wear behavior of AISI 12L14 steel.
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.
Development of resistance to serotonin-induced itch in bile duct ligated mice.
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.
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
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.
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.
Predicting impulsive self-injurious behavior in a sample of adult women.
Black, Emma B; Mildred, Helen
2013-01-01
Different types of self-injury have been classified as reflecting impulsive and compulsive characteristics (article by Simeon and Favazza [Self-injurious Behaviors: Assessment and Treatment {pp 1-28}. Washington, DC: American Psychiatric Publishing, Inc, 2001]). The current research used a prospective design to evaluate whether there is a progression between these different types of self-injurious behaviors (SIB) over time. Support was found for a progression from compulsive SIB (including hair pulling, nail-biting, skin picking, scratching, and preventing wounds from healing) to impulsive SIB (including cutting, burning, carving, pin sticking, and punching) in a group of adult women (N = 106). Other factors hypothesized to be linked to this outcome were disordered eating, age, and personality facets of impulsivity (specifically, urgency and lack of perseverance). Of these variables, only urgency positively predicted impulsive SIB at the study's conclusion. These findings are discussed, limitations of the study are noted, and directions for future research are outlined.
Diagnostic issues in self-mutilation.
Favazza, A R; Rosenthal, R J
1993-02-01
Pathological self-mutilation--the deliberate alteration or destruction of body tissue without conscious suicidal intent--was examined both as a symptom of mental disorders and as a distinct syndrome. Data from more than 250 articles and books were reviewed, as well as data obtained by the authors from their extensive clinical experience in treating self-mutilating patients. The diverse behaviors that constitute pathological self-mutilation can be categorized into three basic types: major--infrequent acts that result in significant tissue damage, usually associated with psychoses and acute intoxications; stereotypic--fixed, rhythmic behavior seemingly devoid of symbolism, commonly associated with mental retardation; and superficial or moderate--behavior such as skin cutting, burning, and scratching associated with a variety of mental disorders. The authors propose that a syndrome of repetitive superficial or moderate self-mutilation should be regarded as an axis I impulse disorder. In most cases, the syndrome coexists with character pathology.
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.
Mechanical and corrosive behavior of Ti/TiN multilayer films with different modulation periods
NASA Astrophysics Data System (ADS)
Zhang, Q.; Leng, Y. X.; Qi, F.; Tao, T.; Huang, N.
2007-04-01
Ti/TiN multilayer films with different periods Λ (Λ = λTiN + λTi) were synthesized on 17-4PH stainless steel and silicon wafer using unbalanced magnetron sputtering. The microstructure of the films was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The mechanical properties such as hardness, sliding wear behavior and adhesion were analyzed by means of micro-hardness, ball-on-disc and scratch tests. The anodic polarization characteristics were measured in a 3% NaCl solution at room temperature to examine the corrosion resistance. Moreover, the corrosion resistance in a 350 °C water vapor ambience also was analyzed. XRD revealed a gradual TiNx transition layer between Ti and TiN. The SEM results confirmed the periodicity of the Ti/TiN multilayer films. The hardness and wear resistance of the Ti/TiN multilayer films increased with decrease of the modulation period. The adhesion strength between Ti/TiN multilayer films and 17-4PH substrate was improved with proper modulation period. The Ti/TiN multilayer films can for a corrosion protective coating on 17-4PH stainless steel in 3% NaCl solution, however the corrosion resistance at 350 °C vapor ambience decreased for the period Λ below 200 nm.
GRAHAM NELSON AND ANDREW HANKS WITH BREADBOARD ENGINE PROJECT CO
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.
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.
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.
Dual stimuli responsive self-reporting material for chemical reservoir coating
NASA Astrophysics Data System (ADS)
Lee, Tae Hee; Song, Young Kyu; Park, Sun Hee; Park, Young Il; Noh, Seung Man; Kim, Jin Chul
2018-03-01
In this study, we introduce a novel dual stimuli responsive self-reporting thiol-epoxy thermoset (DSRTET) coatings which can detect both crack occurrence and pH variation. For crack detection, microcapsule containing tetraphenylethylene (TPE) which exhibits aggregation induced emission (AIE) effect was prepared via multi-step emulsion polymerization and dispersed in DSRTET coatings. For pH variation detection, commercial thymol blue as a pH indicator was added into the polymer matrix. The effect of microcapsule contents in DSRTET on their curing behavior, material properties, and crack sensitivity was characterized using an oscillatory rheology, rigid body pendulum test (RPT), nano-indentation test (NST), universal test machine (UTM) and scratch tester. It was revealed that crack sensitivity of DSRTET coatings was greatly influenced by material properties as well as microcapsule content. The color transition of DSRTET coatings in response to acid or base solution were quantitatively investigated using a multi-angle spectrophotometer after simple acid and base solution drop tests. The color of DSRTET coatings changed from a pale green to red for acidic solution and to blue for basic solution. Finally, The DSRTET used in this study was applied to laboratory scale chemical reservoirs in order to verify the potential as a dual stimuli response self-reporting coating which can detect both crack in coating material and chemical spill caused by the leakage or breakage of the reservoir part.
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.
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
Fitness testing as a discriminative tool for the diagnosis and monitoring of fibromyalgia.
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.
NASA Astrophysics Data System (ADS)
Wang, Song; Li, Junhui; Lu, Junzhe; Tyagi, Rajnesh; Liao, Zhenhua; Feng, Pingfa; Liu, Weiqiang
2017-05-01
The artificial cervical disk was simplified and considered as a ball-on-socket model with the material configuration of ultra-high molecular weight polyethylene and Ti6Al4V (PE-on-TC4). In order to improve the wear resistance, an optimized thermal oxidation (TO) coating was applied on TC4 component. The long-term wear behavior of the model was assessed in vitro using a wear simulator under 10 million cycles (MC) testing intervals. The biological behavior was investigated by bone marrow-derived mesenchymal stem cells (BMSCs) cell attachment and cell viability/proliferation assays, respectively. The total average wear rate for PE/TC4 pair was found to be 0.81 mg/MC, whereas the same was about 0.96 mg/MC for PE/TO pair. The wear rate of the metal has been neglected in comparison with that of the mating polymer. PE component was found to suffer severe damage characterized by scratches, fatigue cracks and arc-shaped wear grooves on the edge zone of ball. The dominant wear mechanism was abrasion for metal component while the dominant failure mechanism was a mix of plowing, fatigue and plastic deformation for polymer component. TO coating improved the cell attachment property of TC4, and the cell viability results were also quite good. TO coating protected TC4 from being plowed and avoided the release of toxic metal ions. However, this intensified the wear of PE component. Considering the biotribological and biological behavior in totality, TO coating could still be promising when applied in articulation surfaces.
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)
Spike threshold dynamics in spinal motoneurons during scratching and swimming.
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.
Darmani, Nissar A.; Wang, Yaozhi; Abad, Joseph; Ray, Andrew P.; Thrush, Gerald R.; Ramirez, Juan
2008-01-01
Substance P (SP) is thought to play a cardinal role in emesis via the activation of central tachykinin NK1 receptors during the delayed phase of vomiting produced by chemotherapeutics. Although the existing supportive evidence is significant, due to lack of an appropriate animal model, the evidence is indirect. As yet, no study has confirmed that emesis produced by SP or a selective NK1 receptor agonist is sensitive to brain penetrating antagonists of either NK1, NK2, or NK3 receptors. The goals of this investigation were to demonstrate: 1) whether intraperitoneal (i.p.) administration of either SP, a brain penetrating (GR73632) or non-penetrating (e.g. SarMet – SP) NK1 receptor agonist, an NK2 receptor agonist (GR64349), or an NK3 receptor agonist (Pro7-NKB), would induce vomiting and/or scratching in the least shrew (Cryptotis parva) in a dose-dependent manner; and whether these effects are sensitive to the above selective receptor antagonists; 2) whether an exogenous emetic dose of SP (50 mg/kg, i.p.) can penetrate into the shrew brain stem and frontal cortex; 3) whether GR73632 (2.5 mg/kg, i.p.)-induced activation of NK1 receptors increases Fos-measured neuronal activity in the neurons of both brain stem emetic nuclei and the enteric nervous system of the gut; and 4) whether selective ablation of peripheral NK1 receptors can affect emesis produced by GR73632. The results clearly demonstrated that while SP produced vomiting only, GR73632 caused both emesis and scratching behavior dose-dependently in shrews, and these effects were sensitive to NK1-, but not NK2- or NK3-receptor antagonists. Neither the selective, non-penetrating NK1 receptor agonists, nor the selective NK2- or NK3-receptor agonists, caused a significant dose-dependent behavioral effect. An emetic dose of SP selectively and rapidly penetrated the brain stem but not the frontal cortex. Systemic GR73632 increased Fos expression in the enteric nerve plexi, the medial subnucleus of nucleus tractus solitarius, and the dorsal motor nucleus of the vagus, but not the area postrema. Ablation of peripheral NK1 receptors attenuated the ability of GR73632 to induce a maximal frequency of emesis and shifted its percent animals vomiting dose-response curve to the right. The NK1-ablated shrews exhibited scratching behavior after systemic GR73632-injection. These results, for the first time, affirm a cardinal role for central NK1 receptors in SP-induced vomiting, and a facilitatory role for gastrointestinal NK1 receptors. In addition, these data support the validation of the least shrew as a specific and rapid behavioral animal model to screen concomitantly both the CNS penetration and the antiemetic potential of tachykinin NK1 receptor antagonists. PMID:18471804
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...
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
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)
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.
Effect of negative bias on TiAlSiN coating deposited on nitrided Zircaloy-4
NASA Astrophysics Data System (ADS)
Jun, Zhou; Zhendong, Feng; Xiangfang, Fan; Yanhong, Liu; Huanlin, Li
2018-01-01
TiAlSiN coatings were deposited on the nitrided Zircaloy-4 by multi-arc ion plating at -100 V, -200 V and -300 V. In this study, the high temperature oxidation behavior of coatings was tested by a box-type resistance furnace in air for 3 h at 800 °C; the macro-morphology of coatings was observed and analyzed by a zoom-stereo microscope; the micro-morphology of coatings was analyzed by a scanning electron microscopy (SEM), and the chemical elements of samples were analyzed by an energy dispersive spectroscopy(EDS); the adhesion strength of the coating to the substrate was measured by an automatic scratch tester; and the phases of coatings were analyzed by an X-ray diffractometer(XRD). Results show that the coating deposited at -100 V shows better high temperature oxidation resistance behavior, at the same time, Al elements contained in the coating is of the highest amount, meanwhile, the adhesion strength of the coating to the substrate is the highest, which is 33N. As the bias increases, high temperature oxidation resistance behavior of the coating weakens first and then increases, the amount of large particles on the surface of the coating increases first and then decreases whereas the density of the coating decreases first and then increases, and adhesion strength of the coating to the substrate increases first and then weakens. The coating's quality is relatively poor when the bias is -200 V.
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…
"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…
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…
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…
Cat-scratch disease presenting as a solitary splenic abscess in an elderly man.
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.
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.
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.
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.
Segmentation of overweight Americans and opportunities for social marketing
Kolodinsky, Jane; Reynolds, Travis
2009-01-01
Background The food industry uses market segmentation to target products toward specific groups of consumers with similar attitudinal, demographic, or lifestyle characteristics. Our aims were to identify distinguishable segments within the US overweight population to be targeted with messages and media aimed at moving Americans toward more healthy weights. Methods Cluster analysis was used to identify segments of consumers based on both food and lifestyle behaviors related to unhealthy weights. Drawing from Social Learning Theory, the Health Belief Model, and existing market segmentation literature, the study identified five distinct, recognizable market segments based on knowledge and behavioral and environmental factors. Implications for social marketing campaigns designed to move Americans toward more healthy weights were explored. Results The five clusters identified were: Highest Risk (19%); At Risk (22%); Right Behavior/Wrong Results (33%); Getting Best Results (13%); and Doing OK (12%). Ninety-nine percent of those in the Highest Risk cluster were overweight; members watched the most television and exercised the least. Fifty-five percent of those in the At Risk cluster were overweight; members logged the most computer time and almost half rarely or never read food labels. Sixty-six percent of those in the Right Behavior/Wrong Results cluster were overweight; however, 95% of them were familiar with the food pyramid. Members reported eating a low percentage of fast food meals (8%) compared to other groups but a higher percentage of other restaurant meals (15%). Less than six percent of those in the Getting Best Results cluster were overweight; every member read food labels and 75% of members' meals were "made from scratch." Eighteen percent of those in the Doing OK cluster were overweight; members watched the least television and reported eating 78% of their meals "made from scratch." Conclusion This study demonstrated that five distinct market segments can be identified for social marketing efforts aimed at addressing the obesity epidemic. Through the identification of these five segments, social marketing campaigns can utilize selected channels and messages that communicate the most relevant and important information. The results of this study offer insight into how segmentation strategies and social marketing messages may improve public health. PMID:19267936
Segmentation of overweight Americans and opportunities for social marketing.
Kolodinsky, Jane; Reynolds, Travis
2009-03-08
The food industry uses market segmentation to target products toward specific groups of consumers with similar attitudinal, demographic, or lifestyle characteristics. Our aims were to identify distinguishable segments within the US overweight population to be targeted with messages and media aimed at moving Americans toward more healthy weights. Cluster analysis was used to identify segments of consumers based on both food and lifestyle behaviors related to unhealthy weights. Drawing from Social Learning Theory, the Health Belief Model, and existing market segmentation literature, the study identified five distinct, recognizable market segments based on knowledge and behavioral and environmental factors. Implications for social marketing campaigns designed to move Americans toward more healthy weights were explored. The five clusters identified were: Highest Risk (19%); At Risk (22%); Right Behavior/Wrong Results (33%); Getting Best Results (13%); and Doing OK (12%). Ninety-nine percent of those in the Highest Risk cluster were overweight; members watched the most television and exercised the least. Fifty-five percent of those in the At Risk cluster were overweight; members logged the most computer time and almost half rarely or never read food labels. Sixty-six percent of those in the Right Behavior/Wrong Results cluster were overweight; however, 95% of them were familiar with the food pyramid. Members reported eating a low percentage of fast food meals (8%) compared to other groups but a higher percentage of other restaurant meals (15%). Less than six percent of those in the Getting Best Results cluster were overweight; every member read food labels and 75% of members' meals were "made from scratch." Eighteen percent of those in the Doing OK cluster were overweight; members watched the least television and reported eating 78% of their meals "made from scratch." This study demonstrated that five distinct market segments can be identified for social marketing efforts aimed at addressing the obesity epidemic. Through the identification of these five segments, social marketing campaigns can utilize selected channels and messages that communicate the most relevant and important information. The results of this study offer insight into how segmentation strategies and social marketing messages may improve public health.
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.
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…
Thoracic osteomyelitis and epidural abscess formation due to cat scratch disease: case report.
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.
Improving response rate and quality of survey data with a scratch lottery ticket incentive
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
Fabrication mechanism of friction-induced selective etching on Si(100) surface
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
Fabrication mechanism of friction-induced selective etching on Si(100) surface.
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.
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.
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®.
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
Greenblatt, Daniel; Krupp, Lauren B; Belman, Anita L
2013-01-01
Parainfectious disorders of the nervous system encompass those meningo-encephalo-radiculomyelitic conditions that are temporally associated with a systemic infection, antigenic stimuli, or toxin exposure, in the absence of evidence of direct neuronal infection or invasion of the central nervous system (CNS) or peripheral nervous system (PNS). Pathogenetic mechanisms can be due to immune-mediated processes (such as bystander activation, molecular mimicy) or the inciting insult can be due to toxic factors, as in the case of botulism. A myriad of clinical manifestations can occur including headache, seizures, and mental status changes, ranging from mood and behavioral disturbances to varying levels of alteration in consciousness. Focal neurological deficits can include aphasia, hemiparesis, or paraparesis. The PNS can also be affected leading to cranial nerve involvement, focal or multifocal neuropathies, and dysfunction of the autonomic nervous system. Diagnosis is based not only on the history, examination, laboratory, and neuroimaging data but also on epidemiological factors. The parainfectious disorders covered in this review are cat scratch disease, Lyme borreliosis, legionellosis, brucellosis, botulism, pertussis, and mycoplasma. Each is associated with a distinct organism, has both systemic and neurological manifestations, and has a different epidemiological profile. Copyright © 2013 Elsevier B.V. All rights reserved.
The pattern of self-harm in Fars Province in South Iran: A population-based study.
Gholamzadeh, Saeid; Zahmatkeshan, Mozhghan; Zarenezhad, Mohammad; Ghaffari, Elaheh; Hoseni, Sanaz
2017-10-01
Non-suicidal self-harm includes cutting, scratching, burning and minor overdosing. There have been few studies that have examined the rate and pattern of self-harm among different individuals of the society. We performed a population-based study to determine different aspects of non-suicidal self-harm in cases referred to legal medicine organization of Fars Province and south Iran. In a population-based longitudinal survey, we applied data from cases referred to legal medicine organization of Fars province. The survey included questions about the history, method, frequency, age of onset and help-seeking for non-suicidal self-harm. The data about non-suicidal self-harm were collected since 2007 to 2011 and analyzed using students' T-test for continuous data and χ 2 for binary or categorical data using SPSS ver. 21.0. Totally 2166 individuals were diagnosed who had ever harmed themselves. Self-injuries such as cutting, scratching and self-hitting were the most common forms of non-suicidal self-harm (83.2%). The mean age of onset was 25.7 ± 2.6 years. Self-injury was more frequent in males and individuals with lower education levels mostly unemployed. The most frequent injury site was posterior side of the body for example shoulders (157; 9.8%) and the most type of the injury was bruise in 398(55.26%) cases. Hard objects (1197; 55.26%) were the most used devices for self-injury followed by cutting and sharp devices. Among those who reported non-suicidal self-harm, 56% had sought help while self-injury. We found a high prevalence of non-suicidal self-harm in different individuals of the society in Fars province since 2007 to 2011. Many mental-health symptoms as well as legal and financial gains should be evaluated for any association with this behavior. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
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.
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
LudusScope: Accessible Interactive Smartphone Microscopy for Life-Science Education.
Kim, Honesty; Gerber, Lukas Cyrill; Chiu, Daniel; Lee, Seung Ah; Cira, Nate J; Xia, Sherwin Yuyang; Riedel-Kruse, Ingmar H
2016-01-01
For centuries, observational microscopy has greatly facilitated biology education, but we still cannot easily and playfully interact with the microscopic world we see. We therefore developed the LudusScope, an accessible, interactive do-it-yourself smartphone microscopy platform that promotes exploratory stimulation and observation of microscopic organisms, in a design that combines the educational modalities of build, play, and inquire. The LudusScope's touchscreen and joystick allow the selection and stimulation of phototactic microorganisms such as Euglena gracilis with light. Organismal behavior is tracked and displayed in real time, enabling open and structured game play as well as scientific inquiry via quantitative experimentation. Furthermore, we used the Scratch programming language to incorporate biophysical modeling. This platform is designed as an accessible, low-cost educational kit for easy construction and expansion. User testing with both teachers and students demonstrates the educational potential of the LudusScope, and we anticipate additional synergy with the maker movement. Transforming observational microscopy into an interactive experience will make microbiology more tangible to society, and effectively support the interdisciplinary learning required by the Next Generation Science Standards.
LudusScope: Accessible Interactive Smartphone Microscopy for Life-Science Education
Kim, Honesty; Gerber, Lukas Cyrill; Chiu, Daniel; Lee, Seung Ah; Cira, Nate J.; Xia, Sherwin Yuyang; Riedel-Kruse, Ingmar H.
2016-01-01
For centuries, observational microscopy has greatly facilitated biology education, but we still cannot easily and playfully interact with the microscopic world we see. We therefore developed the LudusScope, an accessible, interactive do-it-yourself smartphone microscopy platform that promotes exploratory stimulation and observation of microscopic organisms, in a design that combines the educational modalities of build, play, and inquire. The LudusScope’s touchscreen and joystick allow the selection and stimulation of phototactic microorganisms such as Euglena gracilis with light. Organismal behavior is tracked and displayed in real time, enabling open and structured game play as well as scientific inquiry via quantitative experimentation. Furthermore, we used the Scratch programming language to incorporate biophysical modeling. This platform is designed as an accessible, low-cost educational kit for easy construction and expansion. User testing with both teachers and students demonstrates the educational potential of the LudusScope, and we anticipate additional synergy with the maker movement. Transforming observational microscopy into an interactive experience will make microbiology more tangible to society, and effectively support the interdisciplinary learning required by the Next Generation Science Standards. PMID:27706189
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
NASA Astrophysics Data System (ADS)
Ye, Yewei; Jia, Shujuan; Zhang, Dawei; Liu, Wei; Zhao, Haichao
2018-03-01
The thin and thick diamond-like carbon (DLC) films were prepared by unbalanced magnetron sputtering technique on 304L stainless steels and (100) silicon wafers. Microstructure, mechanical, corrosion and tribological properties were systematically investigated by SEM, Raman, nanoindenter, scratch tester, modulab electrochemical workstation and R-tec multifunctional tribological tester. Results showed that the adhesion force presented a descending trend with the growth in soaking time. The adhesion force of the thin DLC film with high residual compressive stress (‑3.72 GPa) was higher than that of the thick DLC film (‑2.96 GPa). During the corrosion test, the thick DLC film showed a higher impendence and a lower corrosion current density than the thin DLC film, which is attributed to the barrier action of large thickness. Compared to bare 304L substrate, the friction coefficients and wear rates of DLC films in seawater were obviously decreased. Meanwhile, the thin DLC film with ideal residual compressive stress, super adhesion force and good plastic deformation resistance revealed an excellent anti-wear ability in seawater.
Species-specific response-topography of chickens' and pigeons' water-induced autoshaped responding.
Ploog, Bertram O
2014-07-01
Four pigeons and eight chickens received autoshaping training where a keylight (conditioned stimulus) signaled response-independent deliveries of water (unconditioned stimulus). Pigeons drink while keeping their beaks submerged in water and moving their beaks to create suction ("mumbling"), whereas chickens drink by trapping a small amount of water in their mouths and then lifting their heads so the water trickles down. This experiment tested whether these and other species-specific differences in drinking and related behaviors of pigeons and chickens would be reflected in the form of conditioned (autoshaped) responding. Touchscreens and videotapes were used for data recording. Results showed that chickens moved their heads more than pigeons when drinking (unconditioned response). The birds also differed in conditioned responding in the presence of the keylight: Pigeons produced more keyswitch closures and mumbled at the keylight more than chickens whereas chickens scratched more than pigeons. In conclusion, with this unique comparative method that employed identical contingencies and comparable deprivation levels, species-specific differences in unconditioned responses and, more importantly, differences in their corresponding conditioned responses were observed. Copyright © 2014 Elsevier B.V. All rights reserved.
Liu, Boyi; Tai, Yan; Achanta, Satyanarayana; Kaelberer, Melanie M.; Caceres, Ana I.; Shao, Xiaomei; Fang, Jianqiao; Jordt, Sven-Eric
2016-01-01
Poison ivy-induced allergic contact dermatitis (ACD) is the most common environmental allergic condition in the United States. Case numbers of poison ivy ACD are increasing due to growing biomass and geographical expansion of poison ivy and increasing content of the allergen, urushiol, likely attributable to rising atmospheric CO2. Severe and treatment-resistant itch is the major complaint of affected patients. However, because of limited clinical data and poorly characterized models, the pruritic mechanisms in poison ivy ACD remain unknown. Here, we aim to identify the mechanisms of itch in a mouse model of poison ivy ACD by transcriptomics, neuronal imaging, and behavioral analysis. Using transcriptome microarray analysis, we identified IL-33 as a key cytokine up-regulated in the inflamed skin of urushiol-challenged mice. We further found that the IL-33 receptor, ST2, is expressed in small to medium-sized dorsal root ganglion (DRG) neurons, including neurons that innervate the skin. IL-33 induces Ca2+ influx into a subset of DRG neurons through neuronal ST2. Neutralizing antibodies against IL-33 or ST2 reduced scratching behavior and skin inflammation in urushiol-challenged mice. Injection of IL-33 into urushiol-challenged skin rapidly exacerbated itch-related scratching via ST2, in a histamine-independent manner. Targeted silencing of neuronal ST2 expression by intrathecal ST2 siRNA delivery significantly attenuated pruritic responses caused by urushiol-induced ACD. These results indicate that IL-33/ST2 signaling is functionally present in primary sensory neurons and contributes to pruritus in poison ivy ACD. Blocking IL-33/ST2 signaling may represent a therapeutic approach to ameliorate itch and skin inflammation related to poison ivy ACD. PMID:27821781
Liu, Boyi; Tai, Yan; Achanta, Satyanarayana; Kaelberer, Melanie M; Caceres, Ana I; Shao, Xiaomei; Fang, Jianqiao; Jordt, Sven-Eric
2016-11-22
Poison ivy-induced allergic contact dermatitis (ACD) is the most common environmental allergic condition in the United States. Case numbers of poison ivy ACD are increasing due to growing biomass and geographical expansion of poison ivy and increasing content of the allergen, urushiol, likely attributable to rising atmospheric CO 2 Severe and treatment-resistant itch is the major complaint of affected patients. However, because of limited clinical data and poorly characterized models, the pruritic mechanisms in poison ivy ACD remain unknown. Here, we aim to identify the mechanisms of itch in a mouse model of poison ivy ACD by transcriptomics, neuronal imaging, and behavioral analysis. Using transcriptome microarray analysis, we identified IL-33 as a key cytokine up-regulated in the inflamed skin of urushiol-challenged mice. We further found that the IL-33 receptor, ST2, is expressed in small to medium-sized dorsal root ganglion (DRG) neurons, including neurons that innervate the skin. IL-33 induces Ca 2+ influx into a subset of DRG neurons through neuronal ST2. Neutralizing antibodies against IL-33 or ST2 reduced scratching behavior and skin inflammation in urushiol-challenged mice. Injection of IL-33 into urushiol-challenged skin rapidly exacerbated itch-related scratching via ST2, in a histamine-independent manner. Targeted silencing of neuronal ST2 expression by intrathecal ST2 siRNA delivery significantly attenuated pruritic responses caused by urushiol-induced ACD. These results indicate that IL-33/ST2 signaling is functionally present in primary sensory neurons and contributes to pruritus in poison ivy ACD. Blocking IL-33/ST2 signaling may represent a therapeutic approach to ameliorate itch and skin inflammation related to poison ivy ACD.
Yeom, Mijung; Kim, Sung-Hun; Lee, Bombi; Han, Jeong-Jun; Chung, Guk Hoon; Choi, Hee-Don; Lee, Hyejung; Hahm, Dae-Hyun
2012-08-01
Irritant contact dermatitis (ICD) is an inflammatory skin disease triggered by exposure to a chemical that is toxic or irritating to the skin. A major characteristic of chronic ICD is an inflammatory dry-skin condition with associated itching. Although glucosylceramide (GlcCer) is known to improve the skin barrier function, its mechanism of action is unknown. Using a mouse model of oxazolone-induced chronic ICD, this study investigated the effects of oral administration of GlcCer on inflammatory dry skin. Chronic ICD was induced by repeated application of oxazolone in mice. GlcCer was orally administered once daily throughout the elicitation phase. The beneficial efficacy of GlcCer on cutaneous inflammation was evaluated by assessing ear thickness, lymph node weight, histological findings, and mRNA expression of pro-inflammatory cytokines such as IL-1β and IL-6. Additionally, parameters of the itch-associated response, including scratching behavior, water content of the skin, and aquaporin-3 levels in the lesional ear, were measured. Oral GlcCer administration significantly suppressed mRNA expression of the pro-inflammatory cytokines IL-1β and IL-6. GlcCer also suppressed ear swelling, lymph node weight gains, and infiltration of leukocytes and mast cells in ICD mice. In oxazolone-induced ICD mice, GlcCer significantly inhibited irritant-related scratching behavior and dehydration of the stratum corneum, and decreased aquaporin-3 expression. Our results indicate that GlcCer suppressed inflammation not only by inhibiting cytokine production but also by repairing the skin barrier function, suggesting a potential beneficial role for GlcCer in the improvement of chronic ICD. Copyright © 2012 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.
Chen, Yong; Fang, Quan; Wang, Zilong; Zhang, Jennifer Y.; MacLeod, Amanda S.; Hall, Russell P.; Liedtke, Wolfgang B.
2016-01-01
TRPV4 ion channels function in epidermal keratinocytes and in innervating sensory neurons; however, the contribution of the channel in either cell to neurosensory function remains to be elucidated. We recently reported TRPV4 as a critical component of the keratinocyte machinery that responds to ultraviolet B (UVB) and functions critically to convert the keratinocyte into a pain-generator cell after excess UVB exposure. One key mechanism in keratinocytes was increased expression and secretion of endothelin-1, which is also a known pruritogen. Here we address the question of whether TRPV4 in skin keratinocytes functions in itch, as a particular form of “forefront” signaling in non-neural cells. Our results support this novel concept based on attenuated scratching behavior in response to histaminergic (histamine, compound 48/80, endothelin-1), not non-histaminergic (chloroquine) pruritogens in Trpv4 keratinocyte-specific and inducible knock-out mice. We demonstrate that keratinocytes rely on TRPV4 for calcium influx in response to histaminergic pruritogens. TRPV4 activation in keratinocytes evokes phosphorylation of mitogen-activated protein kinase, ERK, for histaminergic pruritogens. This finding is relevant because we observed robust anti-pruritic effects with topical applications of selective inhibitors for TRPV4 and also for MEK, the kinase upstream of ERK, suggesting that calcium influx via TRPV4 in keratinocytes leads to ERK-phosphorylation, which in turn rapidly converts the keratinocyte into an organismal itch-generator cell. In support of this concept we found that scratching behavior, evoked by direct intradermal activation of TRPV4, was critically dependent on TRPV4 expression in keratinocytes. Thus, TRPV4 functions as a pruriceptor-TRP in skin keratinocytes in histaminergic itch, a novel basic concept with translational-medical relevance. PMID:26961876
RAND Workshop on Antiproton Science and Technology, Annotated Executive Summary. (October 6-9, 1987)
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
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
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.
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.
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.
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.
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
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…
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…
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…
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…
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…
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…
Processing of AlCoCrFeNiTi high entropy alloy by atmospheric plasma spraying
NASA Astrophysics Data System (ADS)
Löbel, M.; Lindner, T.; Kohrt, C.; Lampke, T.
2017-03-01
High Entropy Alloys (HEA) are gaining increasing interest due to their unique combination of properties. Especially the combination of high mechanical strength and hardness with distinct ductility makes them attractive for numerous applications. One interesting alloy system that exhibits excellent properties in bulk state is AlCoCrFeNiTi. A high strength, wear resistance and high-temperature resistance are the necessary requirements for the application in surface engineering. The suitability of blended, mechanically ball milled and inert gas atomized feedstock powders for the development of atmospheric plasma sprayed (APS) coatings is investigated in this study. The ball milled and inert gas atomized powders were characterized regarding their particle morphology, phase composition, chemical composition and powder size distribution. The microstructure and phase composition of the thermal spray coatings produced with different feedstock materials was investigated and compared with the feedstock material. Furthermore, the Vickers hardness (HV) was measured and the wear behavior under different tribological conditions was tested in ball-on-disk, oscillating wear and scratch tests. The results show that all produced feedstock materials and coatings exhibit a multiphase composition. The coatings produced with inert gas atomized feedstock material provide the best wear resistance and the highest degree of homogeneity.
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.
Evolution of Self-Organized Task Specialization in Robot Swarms
Ferrante, Eliseo; Turgut, Ali Emre; Duéñez-Guzmán, Edgar; Dorigo, Marco; Wenseleers, Tom
2015-01-01
Division of labor is ubiquitous in biological systems, as evidenced by various forms of complex task specialization observed in both animal societies and multicellular organisms. Although clearly adaptive, the way in which division of labor first evolved remains enigmatic, as it requires the simultaneous co-occurrence of several complex traits to achieve the required degree of coordination. Recently, evolutionary swarm robotics has emerged as an excellent test bed to study the evolution of coordinated group-level behavior. Here we use this framework for the first time to study the evolutionary origin of behavioral task specialization among groups of identical robots. The scenario we study involves an advanced form of division of labor, common in insect societies and known as “task partitioning”, whereby two sets of tasks have to be carried out in sequence by different individuals. Our results show that task partitioning is favored whenever the environment has features that, when exploited, reduce switching costs and increase the net efficiency of the group, and that an optimal mix of task specialists is achieved most readily when the behavioral repertoires aimed at carrying out the different subtasks are available as pre-adapted building blocks. Nevertheless, we also show for the first time that self-organized task specialization could be evolved entirely from scratch, starting only from basic, low-level behavioral primitives, using a nature-inspired evolutionary method known as Grammatical Evolution. Remarkably, division of labor was achieved merely by selecting on overall group performance, and without providing any prior information on how the global object retrieval task was best divided into smaller subtasks. We discuss the potential of our method for engineering adaptively behaving robot swarms and interpret our results in relation to the likely path that nature took to evolve complex sociality and task specialization. PMID:26247819
Evolution of Self-Organized Task Specialization in Robot Swarms.
Ferrante, Eliseo; Turgut, Ali Emre; Duéñez-Guzmán, Edgar; Dorigo, Marco; Wenseleers, Tom
2015-08-01
Division of labor is ubiquitous in biological systems, as evidenced by various forms of complex task specialization observed in both animal societies and multicellular organisms. Although clearly adaptive, the way in which division of labor first evolved remains enigmatic, as it requires the simultaneous co-occurrence of several complex traits to achieve the required degree of coordination. Recently, evolutionary swarm robotics has emerged as an excellent test bed to study the evolution of coordinated group-level behavior. Here we use this framework for the first time to study the evolutionary origin of behavioral task specialization among groups of identical robots. The scenario we study involves an advanced form of division of labor, common in insect societies and known as "task partitioning", whereby two sets of tasks have to be carried out in sequence by different individuals. Our results show that task partitioning is favored whenever the environment has features that, when exploited, reduce switching costs and increase the net efficiency of the group, and that an optimal mix of task specialists is achieved most readily when the behavioral repertoires aimed at carrying out the different subtasks are available as pre-adapted building blocks. Nevertheless, we also show for the first time that self-organized task specialization could be evolved entirely from scratch, starting only from basic, low-level behavioral primitives, using a nature-inspired evolutionary method known as Grammatical Evolution. Remarkably, division of labor was achieved merely by selecting on overall group performance, and without providing any prior information on how the global object retrieval task was best divided into smaller subtasks. We discuss the potential of our method for engineering adaptively behaving robot swarms and interpret our results in relation to the likely path that nature took to evolve complex sociality and task specialization.
Heart rate during conflicts predicts post-conflict stress-related behavior in greylag geese.
Wascher, Claudia A F; Fraser, Orlaith N; Kotrschal, Kurt
2010-12-20
Social stressors are known to be among the most potent stressors in group-living animals. This is not only manifested in individual physiology (heart rate, glucocorticoids), but also in how individuals behave directly after a conflict. Certain 'stress-related behaviors' such as autopreening, body shaking, scratching and vigilance have been suggested to indicate an individual's emotional state. Such behaviors may also alleviate stress, but the behavioral context and physiological basis of those behaviors is still poorly understood. We recorded beat-to-beat heart rates (HR) of 22 greylag geese in response to agonistic encounters using fully implanted sensor-transmitter packages. Additionally, for 143 major events we analyzed the behavior shown by our focal animals in the first two minutes after an interaction. Our results show that the HR during encounters and characteristics of the interaction predicted the frequency and duration of behaviors shown after a conflict. To our knowledge this is the first study to quantify the physiological and behavioral responses to single agonistic encounters and to link this to post conflict behavior. Our results demonstrate that 'stress-related behaviors' are flexibly modulated by the characteristics of the preceding aggressive interaction and reflect the individual's emotional strain, which is linked to autonomic arousal. We found no support for the stress-alleviating hypothesis, but we propose that stress-related behaviors may play a role in communication with other group members, particularly with pair-partners.
Synthesized multi-station tribo-test system for bio-tribological evaluation in vitro
NASA Astrophysics Data System (ADS)
Wu, Tonghai; Du, Ying; Li, Yang; Wang, Shuo; Zhang, Zhinan
2016-07-01
Tribological tests play an important role on the evaluation of long-term bio-tribological performances of prosthetic materials for commercial fabrication. Those tests focus on the motion simulation of a real joint in vitro with only normal loads and constant velocities, which are far from the real friction behavior of human joints characterized with variable loads and multiple directions. In order to accurately obtain the bio-tribological performances of artificial joint materials, a tribological tester with a miniature four-station tribological system is proposed with four distinctive features. Firstly, comparability and repeatability of a test are ensured by four equal stations of the tester. Secondly, cross-linked scratch between tribo-pairs of human joints can be simulated by using a gear-rack meshing mechanism to produce composite motions. With this mechanism, the friction tracks can be designed by varying reciprocating and rotating speeds. Thirdly, variable loading system is realized by using a ball-screw mechanism driven by a stepper motor, by which loads under different gaits during walking are simulated. Fourthly, dynamic friction force and normal load can be measured simultaneously. The verifications of the performances of the developed tester show that the variable frictional tracks can produce different wear debris compared with one-directional tracks, and the accuracy of loading and friction force is within ±5%. Thus the high consistency among different stations can be obtained. Practically, the proposed tester system could provide more comprehensive and accurate bio-tribological evaluations for prosthetic materials.
VGLUT2-dependent sensory neurons in the TRPV1 population regulate pain and itch.
Lagerström, Malin C; Rogoz, Katarzyna; Abrahamsen, Bjarke; Persson, Emma; Reinius, Björn; Nordenankar, Karin; Olund, Caroline; Smith, Casey; Mendez, José Alfredo; Chen, Zhou-Feng; Wood, John N; Wallén-Mackenzie, Asa; Kullander, Klas
2010-11-04
The natural response to itch sensation is to scratch, which relieves the itch through an unknown mechanism. Interaction between pain and itch has been frequently demonstrated, and the selectivity hypothesis of itch, based on data from electrophysiological and behavioral experiments, postulates the existence of primary pain afferents capable of repressing itch. Here, we demonstrate that deletion of vesicular glutamate transporter (VGLUT) 2 in a subpopulation of neurons partly overlapping with the vanilloid receptor (TRPV1) primary afferents resulted in a dramatic increase in itch behavior accompanied by a reduced responsiveness to thermal pain. The increased itch behavior was reduced by administration of antihistaminergic drugs and by genetic deletion of the gastrin-releasing peptide receptor, demonstrating a dependence on VGLUT2 to maintain normal levels of both histaminergic and nonhistaminergic itch. This study establishes that VGLUT2 is a major player in TRPV1 thermal nociception and also serves to regulate a normal itch response. Copyright © 2010 Elsevier Inc. All rights reserved.
Convolutional Neural Networks for Medical Image Analysis: Full Training or Fine Tuning?
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.
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
Diverse Clinical Signs of Ocular Involvement in Cat Scratch Disease.
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.
Ballistic impact resistance of selected organic ophthalmic lenses.
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.
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…
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…
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…
Contagious itch: what we know and what we would like to know
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
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.
Occupational health hazards in veterinary medicine: Zoonoses and other biological hazards
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
Development of a Detonation Diffuser
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
Collaborative Research and Development (CR&D). Task Order 0049: Tribological Modeling
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
Exploring Deep Learning and Transfer Learning for Colonic Polyp Classification
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
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.
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.
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.
Corticosteroid Treatment for Prolonged Fever in Hepatosplenic Cat-Scratch Disease: A Case Study.
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.
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.
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.
jsPsych: a JavaScript library for creating behavioral experiments in a Web browser.
de Leeuw, Joshua R
2015-03-01
Online experiments are growing in popularity, and the increasing sophistication of Web technology has made it possible to run complex behavioral experiments online using only a Web browser. Unlike with offline laboratory experiments, however, few tools exist to aid in the development of browser-based experiments. This makes the process of creating an experiment slow and challenging, particularly for researchers who lack a Web development background. This article introduces jsPsych, a JavaScript library for the development of Web-based experiments. jsPsych formalizes a way of describing experiments that is much simpler than writing the entire experiment from scratch. jsPsych then executes these descriptions automatically, handling the flow from one task to another. The jsPsych library is open-source and designed to be expanded by the research community. The project is available online at www.jspsych.org .
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.
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.
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.
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
Naono, R; Nakayama, T; Ikeda, T; Matsusima, O; Nishimori, T
2008-02-01
Desensitization is induced by the repeated administration of high doses of substance P (SP) or hemokinin-1 (HK-1). However, little information is available about the mechanisms involved in the induction of desensitization by these peptides. Thus, to characterize this desensitization, we examined the dose-dependent effect of these peptides, the effect of pretreatment with neurokinin 1(NK1) receptor antagonists, and the effect of pretreatment with inhibitors of protein kinases such as protein kinase A (PKA), protein kinase C (PKC), calcium/calmodulin kinase II (CaMKII) and mitogen-activated protein kinase kinase (MEK). The number of scratchings induced by 10(-3)M SP or HK-1 decreased following pretreatment with 10(-11)-10(-3)M SP or HK-1 with a marked reduction at 10(-3) and 10(-6)M SP or HK-1. The effect of NK1 receptor antagonists on desensitization induced by pretreatment with 10(-6)M SP was marked, whereas there was little effect of pretreatment with these antagonists on 10(-6)M HK-1-induced desensitization. Additionally, 10(-6)M SP- and HK-1-induced desensitization was attenuated by pretreatment with PKA, PKC and MEK inhibitors, except a CaMKII inhibitor that inhibited SP-induced desensitization. These results indicate that the receptor and kinases involved in HK-1-induced desensitization are partially different from those of SP.
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.
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
A case of cat-scratch disease with unusual ophthalmic manifestations.
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.
Comments on Cadmium Alternatives and Testing - IHE vs. EHE (Briefing Charts)
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
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…
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…
Exosome production and its regulation of EGFR during wound healing in renal tubular cells.
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.
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.
An, Guang-Zhou; Xu, Hui; Zhou, Yan; Du, Le; Miao, Xia; Jiang, Da-Peng; Li, Kang-Chu; Guo, Guo-Zhen; Zhang, Chen; Ding, Gui-Rong
2015-01-01
Power-line frequency electromagnetic field (PF-EMF) was reported as a human carcinogen by some epidemiological research, but the conclusion is lack of robust experiment evidence. To identify the effects of long-term PF-EMF exposure on cell behavior, Balb/c 3T3 cells in exponential growth phase were exposed or sham-exposed to 50 Hertz (Hz) PF-EMF at 2.3 mT for 2 hours (h) one day, 5 days every week. After 11 weeks exposure, cells were collected instantly. Cell morphology was observed under invert microscope and Giemsa staining, cell viability was detected by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, cell cycle and apoptosis was examined by flow cytometry, the protein level of Proliferating Cell Nuclear Antigen (PCNA) and CyclinD1 was detected by western blot, cell transformation was examined by soft agar clone assay and plate clone forming test, and cell migration ability was observed by scratch adhesion test. It was found that after PF-EMF exposure, cell morphology, apoptosis, cell migration ability and cell transformation didn’t change. However, compared with sham group, cell viability obviously decreased and cell cycle distribution also changed after 11 weeks PF-EMF exposure. Meanwhile, the protein level of PCNA and CyclinD1 significantly decreased after PF-EMF exposure. These data suggested that although long-term 50Hz PF-EMF exposure under this experimental condition had no effects on apoptosis, cell migration ability and cell transformation, it could affect cell proliferation and cell cycle by down-regulation the expression of PCNA and CyclinD1 protein. PMID:25695503
An, Guang-Zhou; Xu, Hui; Zhou, Yan; Du, Le; Miao, Xia; Jiang, Da-Peng; Li, Kang-Chu; Guo, Guo-Zhen; Zhang, Chen; Ding, Gui-Rong
2015-01-01
Power-line frequency electromagnetic field (PF-EMF) was reported as a human carcinogen by some epidemiological research, but the conclusion is lack of robust experiment evidence. To identify the effects of long-term PF-EMF exposure on cell behavior, Balb/c 3T3 cells in exponential growth phase were exposed or sham-exposed to 50 Hertz (Hz) PF-EMF at 2.3 mT for 2 hours (h) one day, 5 days every week. After 11 weeks exposure, cells were collected instantly. Cell morphology was observed under invert microscope and Giemsa staining, cell viability was detected by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, cell cycle and apoptosis was examined by flow cytometry, the protein level of Proliferating Cell Nuclear Antigen (PCNA) and CyclinD1 was detected by western blot, cell transformation was examined by soft agar clone assay and plate clone forming test, and cell migration ability was observed by scratch adhesion test. It was found that after PF-EMF exposure, cell morphology, apoptosis, cell migration ability and cell transformation didn't change. However, compared with sham group, cell viability obviously decreased and cell cycle distribution also changed after 11 weeks PF-EMF exposure. Meanwhile, the protein level of PCNA and CyclinD1 significantly decreased after PF-EMF exposure. These data suggested that although long-term 50Hz PF-EMF exposure under this experimental condition had no effects on apoptosis, cell migration ability and cell transformation, it could affect cell proliferation and cell cycle by down-regulation the expression of PCNA and CyclinD1 protein.
Automated simulation as part of a design workstation
NASA Technical Reports Server (NTRS)
Cantwell, E.; Shenk, T.; Robinson, P.; Upadhye, R.
1990-01-01
A development project for a design workstation for advanced life-support systems incorporating qualitative simulation, required the implementation of a useful qualitative simulation capability and the integration of qualitative and quantitative simulations, such that simulation capabilities are maximized without duplication. The reason is that to produce design solutions to a system goal, the behavior of the system in both a steady and perturbed state must be represented. The paper reports on the Qualitative Simulation Tool (QST), on an expert-system-like model building and simulation interface toll called ScratchPad (SP), and on the integration of QST and SP with more conventional, commercially available simulation packages now being applied in the evaluation of life-support system processes and components.
A reinforcement learning-based architecture for fuzzy logic control
NASA Technical Reports Server (NTRS)
Berenji, Hamid R.
1992-01-01
This paper introduces a new method for learning to refine a rule-based fuzzy logic controller. A reinforcement learning technique is used in conjunction with a multilayer neural network model of a fuzzy controller. The approximate reasoning based intelligent control (ARIC) architecture proposed here learns by updating its prediction of the physical system's behavior and fine tunes a control knowledge base. Its theory is related to Sutton's temporal difference (TD) method. Because ARIC has the advantage of using the control knowledge of an experienced operator and fine tuning it through the process of learning, it learns faster than systems that train networks from scratch. The approach is applied to a cart-pole balancing system.
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…
MB20B Base Stock as Tarnish Promoter or Preventor.
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
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.
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.
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.
The Ion Channel TRPA1 Is Required for Chronic Itch
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
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
Hangx, Suzanne J T; van der Linden, Arjan; Marcelis, Fons; Liteanu, Emilia
2016-01-19
To predict the behavior of the cement sheath after CO2 injection and the potential for leakage pathways, it is key to understand how the mechanical properties of the cement evolves with CO2 exposure time. We performed scratch-hardness tests on hardened samples of class G cement before and after CO2 exposure. The cement was exposed to CO2-rich fluid for one to six months at 65 °C and 8 MPa Ptotal. Detailed SEM-EDX analyses showed reaction zones similar to those previously reported in the literature: (1) an outer-reacted, porous silica-rich zone; (2) a dense, carbonated zone; and (3) a more porous, Ca-depleted inner zone. The quantitative mechanical data (brittle compressive strength and friction coefficient) obtained for each of the zones suggest that the heterogeneity of reacted cement leads to a wide range of brittle strength values in any of the reaction zones, with only a rough dependence on exposure time. However, the data can be used to guide numerical modeling efforts needed to assess the impact of reaction-induced mechanical failure of wellbore cement by coupling sensitivity analysis and mechanical predictions.
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
De-Icing Systems of Flight Vehicles. Bases of Design Methods for Testing. Part 1,
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
Kim, Donghwan; Lee, Hyunsuk; Bae, Joohyeon; Jeong, Hyomin; Choi, Byeongkeun; Nam, Taehyun; Noh, Jungpil
2018-09-01
Ti-Ni shape memory alloy (SMA) thin films are very attractive material for industrial and medical applications such as micro-actuator, micro-sensors, and stents for blood vessels. An important property besides shape memory effect in the application of SMA thin films is the adhesion between the film and the substrate. When using thin films as micro-actuators or micro-sensors in MEMS, the film must be strongly adhered to the substrate. On the other hand, when using SMA thin films in medical devices such as stents, the deposited alloy thin film must be easily separable from the substrate for efficient processing. In this study, we investigated the effect of substrate roughness on the adhesion of Ti-Ni SMA thin films, as well as the structural properties and phase-transformation behavior of the fabricated films. Ti-Ni SMA thin films were deposited onto etched glass substrates with magnetron sputtering. Radio frequency plasma was used for etching the substrate. The adhesion properties were investigated through progressive scratch test. Structural properties of the films were determined via Feld emission scanning electron microscopy, X-ray diffraction measurements (XRD) and Energy-dispersive X-ray spectroscopy analysis. Phase transformation behaviors were observed with differential scanning calorimetry and low temperature-XRD. Ti-Ni SMA thin film deposited onto rough substrate provides higher adhesive strength than smooth substrate. However the roughness of the substrate has no influence on the growth and crystallization of the Ti-Ni SMA thin films.
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
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.
Paiva, Jose Mario; Fox-Rabinovich, German; Locks Junior, Edinei; Stolf, Pietro; Seid Ahmed, Yassmin; Matos Martins, Marcelo; Bork, Carlos; Veldhuis, Stephen
2018-02-28
In the aluminum die casting process, erosion, corrosion, soldering, and die sticking have a significant influence on tool life and product quality. A number of coatings such as TiN, CrN, and (Cr,Al)N deposited by physical vapor deposition (PVD) have been employed to act as protective coatings due to their high hardness and chemical stability. In this study, the wear performance of two nanocomposite AlTiN and AlCrN coatings with different structures were evaluated. These coatings were deposited on aluminum die casting mold tool substrates (AISI H13 hot work steel) by PVD using pulsed cathodic arc evaporation, equipped with three lateral arc-rotating cathodes (LARC) and one central rotating cathode (CERC). The research was performed in two stages: in the first stage, the outlined coatings were characterized regarding their chemical composition, morphology, and structure using glow discharge optical emission spectroscopy (GDOES), scanning electron microscopy (SEM), and X-ray diffraction (XRD), respectively. Surface morphology and mechanical properties were evaluated by atomic force microscopy (AFM) and nanoindentation. The coating adhesion was studied using Mersedes test and scratch testing. During the second stage, industrial tests were carried out for coated die casting molds. In parallel, tribological tests were also performed in order to determine if a correlation between laboratory and industrial tests can be drawn. All of the results were compared with a benchmark monolayer AlCrN coating. The data obtained show that the best performance was achieved for the AlCrN/Si₃N₄ nanocomposite coating that displays an optimum combination of hardness, adhesion, soldering behavior, oxidation resistance, and stress state. These characteristics are essential for improving the die mold service life. Therefore, this coating emerges as a novelty to be used to protect aluminum die casting molds.
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.
Australian bat lyssavirus: a recently discovered new rhabdovirus.
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.
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.
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.
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.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Sung Bo, E-mail: bolee@snu.ac.kr; Han, Heung Nam, E-mail: hnhan@snu.ac.kr; Lee, Dong Nyung
Much research has been done to reduce dislocation densities for the growth of GaN on sapphire, but has paid little attention to the elastic behavior at the GaN/sapphire interface. In this study, we have examined effects of the addition of Si to a sapphire substrate on its elastic property and on the growth of GaN deposit. Si atoms are added to a c-plane sapphire substrate by ion implantation. The ion implantation results in scratches on the surface, and concomitantly, inhomogeneous distribution of Si. The scratch regions contain a higher concentration of Si than other regions of the sapphire substrate surface,more » high-temperature GaN being poorly grown there. However, high-temperature GaN is normally grown in the other regions. The GaN overlayer in the normally-grown regions is observed to have a lower TD density than the deposit on the bare sapphire substrate (with no Si accommodated). As compared with the film on an untreated, bare sapphire, the cathodoluminescence defect density decreases by 60 % for the GaN layer normally deposited on the Si-ion implanted sapphire. As confirmed by a strain mapping technique by transmission electron microscopy (geometric phase analysis), the addition of Si in the normally deposited regions forms a surface layer in the sapphire elastically more compliant than the GaN overlayer. The results suggest that the layer can largely absorb the misfit strain at the interface, which produces the overlayer with a lower defect density. Our results highlight a direct correlation between threading-dislocation density in GaN deposits and the elastic behavior at the GaN/sapphire interface, opening up a new pathway to reduce threading-dislocation density in GaN deposits.« less
Short communication: use of a mechanical brush by Holstein dairy cattle around parturition.
Newby, Nathalie C; Duffield, Todd F; Pearl, David L; Leslie, Ken E; LeBlanc, Stephen J; von Keyserlingk, Marina A G
2013-04-01
Grooming is a normal behavior that may contribute to relief of stress. The purpose of this study was to investigate the effect of access to a mechanical brush on auto-grooming behavior in parturient cows. The hypothesis was that cows would increase the total time spent scratching using the brush if they had access to a brush around the time of calving, whereas auto-grooming would be lower for the brush group compared with the no-brush group. The use of a mechanical brush was analyzed both in a group-housed pen (72 to 48 h before calving) and in an individual maternity pen (6h before to 6h after calving) in 16 multiparous Holstein cows. In the maternity pen, cows were randomly assigned to have access to the brush or not. The provision of a mechanical brush in the individual maternity pen did not change the amount of time spent auto-grooming but cows did use the brush before calving and after the calf was removed. Despite being housed in pens containing a brush, cows failed to use it when the calf was present. However, cows with access to a brush spent more time licking their calves in the first hour postcalving (β=8.7 min; 95% confidence interval: 1.5, 15.8) than cows that did not have access to a brush. Regardless of treatment, cows increased the time spent auto-grooming and scratching following separation of their newborn calf (β=1.4 min; 95% confidence interval: 0.46, 2.3 and β=0.07 min; 95% confidence interval: 0.02, 0.12, respectively). Further research is warranted to investigate possible benefits of mechanical brush devices at the time of calving, particularly for cows that experience difficult calving and require manual or mechanical assistance. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Spice allergy in celery-sensitive patients.
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.
Berni, M; Lopomo, N; Marchiori, G; Gambardella, A; Boi, M; Bianchi, M; Visani, A; Pavan, P; Russo, A; Marcacci, M
2016-05-01
One of the most important issues leading to the failure of total joint arthroplasty is related to the wear of the plastic components, which are generally made of ultra high molecular weight polyethylene (UHMWPE). Therefore, the reduction of joint wear represents one of the main challenges the research in orthopedics is called to address nowadays. Surface treatments and coatings have been recognized as innovative methods to improve tribological properties, also in the orthopedic field. This work investigated the possibility to realize hard ceramic coatings on the metal component of a prosthesis, by means of Pulsed Plasma Deposition, in order to reduce friction and wear in the standard coupling against UHMWPE. Ti6Al4V substrates were coated with a 2 μm thick yttria-stabilized zirconia (YSZ) layer. The mechanical properties of the YSZ coatings were assessed by nanoindentation tests performed on flat Ti6Al4V substrates. Tribological performance was evaluated using a ball-on-disk tribometer in dry and lubricated (i.e. with fetal bovine serum) highly-stressing conditions, up to an overall distance of 10 km. Tribology was characterized in terms of coefficient of friction (CoF) and wear rate of the UHMWPE disk. After testing, specimens were analyzed through optical microscopy and SEM images, in order to check the wear degradation mechanisms. Progressive loading scratch tests were also performed in dry and wet conditions to determine the effects of the environment on the adhesion of the coating. Our results supported the beneficial effect of YSZ coating on metal components. In particular, the proposed solution significantly reduced UHMWPE wear rate and friction. At 10 km of sliding distance, a wear rate reduction of about 18% in dry configuration and of 4% in presence of serum, was obtained by the coated group compared to the uncoated group. As far as friction in dry condition is concerned, the coating allowed to maintain low CoF values until the end of the tests, with an overall difference of about 40% compared to the uncoated balls. In wet conditions, the friction values were found to be comparable between coated and uncoated materials, mainly due to a premature delamination of the coating. Scratch tests in wet showed in fact a reduction of the critical load required to a complete delamination due to a formation of blister, although no change or damage occurred at the coating during the soaking period. Although conditions of high values of contact pressure were considered, further analyses are however required to fully understand the behavior of YSZ coatings in wet environment and additional research on the deposition process will be mandatory in order to improve the coating tribological performance at long distances addressing orthopedic applications. Copyright © 2016 Elsevier B.V. All rights reserved.
Di Martino, Guido; Capello, Katia; Stefani, Anna Lisa; Tripepi, Luca; Garbo, Angelica; Speri, Marina; Trolese, Matteo; Brichese, Michele; Marangon, Stefano; Bonfanti, Lebana
2017-10-01
Limited information is available on suitable height of transport crates for turkeys. We compared behaviors and physiological indicators of four groups of 10 female turkeys each confined in either conventional (38.5 cm height) or experimental (77 cm height) crates during six commercial pre-slaughter transportations for 86 km (76 ± 4 min) along two tracts with one-lane streets, crossroads, bends, roundabouts (S1 and S2) and a highway tract (H) between S1 and S2. Only 36% of birds in the higher crates maintained a standing position. In conventional versus experimental crates, the frequency of rising attempts was five/bird/hour versus less than one/bird/hour, while wing flapping was seven/bird/hour versus 20/bird/hour, and balance loss was one versus four/bird/hour. The behaviors of both groups differed significantly according to the route tract, with a lower frequency of stress-related behaviors at H. No scratches, fractures or hematomas were detected in any birds after transportation. Crate height had no significant effect on hemato-biochemical markers. These results suggest that crates enabling a standing position may increase potentially dangerous behaviors. Moreover, busy and curvy routes should be avoided, as they may contribute to increasing the frequency of stress-related behaviors. © 2017 Japanese Society of Animal Science.
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.
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.
Polyfibroblast: A Self-Healing and Galvanic Protection Additive
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
Lee, Heeseung; Ko, Mei-Chuan
2015-06-29
How neuropeptides in the primate spinal cord regulate itch and pain is largely unknown. Here we elucidate the sensory functions of spinal opioid-related peptides and gastrin-releasing peptide (GRP) in awake, behaving monkeys. Following intrathecal administration, β-endorphin (10-100 nmol) and GRP (1-10 nmol) dose-dependently elicit the same degree of robust itch scratching, which can be inhibited by mu-opioid peptide (MOP) receptor and GRP receptor (BB2) antagonists, respectively. Unlike β-endorphin, which produces itch and attenuates inflammatory pain, GRP only elicits itch without affecting pain. In contrast, enkephalins (100-1000 nmol) and nociceptin-orphanin FQ (3-30 nmol) only inhibit pain without eliciting itch. More intriguingly, dynorphin A(1-17) (10-100 nmol) dose-dependently attenuates both β-endorphin- and GRP-elicited robust scratching without affecting pain processing. The anti-itch effects of dynorphin A can be reversed by a kappa-opioid peptide (KOP) receptor antagonist nor-binaltorphimine. These nonhuman primate behavioral models with spinal delivery of ligands advance our understanding of distinct functions of neuropeptides for modulating itch and pain. In particular, we demonstrate causal links for itch-eliciting effects by β-endorphin-MOP receptor and GRP-BB2 receptor systems and itch-inhibiting effects by the dynorphin A-KOP receptor system. These studies will facilitate transforming discoveries of novel ligand-receptor systems into future therapies as antipruritics and/or analgesics in humans.
Liu, Tong; Berta, Temugin; Xu, Zhen-Zhong; Park, Chul-Kyu; Zhang, Ling; Lü, Ning; Liu, Qin; Liu, Yang; Gao, Yong-Jing; Liu, Yen-Chin; Ma, Qiufu; Dong, Xinzhong; Ji, Ru-Rong
2012-01-01
Itch, also known as pruritus, is a common, intractable symptom of several skin diseases, such as atopic dermatitis and xerosis. TLRs mediate innate immunity and regulate neuropathic pain, but their roles in pruritus are elusive. Here, we report that scratching behaviors induced by histamine-dependent and -independent pruritogens are markedly reduced in mice lacking the Tlr3 gene. TLR3 is expressed mainly by small-sized primary sensory neurons in dorsal root ganglions (DRGs) that coexpress the itch signaling pathway components transient receptor potential subtype V1 and gastrin-releasing peptide. Notably, we found that treatment with a TLR3 agonist induces inward currents and action potentials in DRG neurons and elicited scratching in WT mice but not Tlr3–/– mice. Furthermore, excitatory synaptic transmission in spinal cord slices and long-term potentiation in the intact spinal cord were impaired in Tlr3–/– mice but not Tlr7–/– mice. Consequently, central sensitization–driven pain hypersensitivity, but not acute pain, was impaired in Tlr3–/– mice. In addition, TLR3 knockdown in DRGs also attenuated pruritus in WT mice. Finally, chronic itch in a dry skin condition was substantially reduced in Tlr3–/– mice. Our findings demonstrate a critical role of TLR3 in regulating sensory neuronal excitability, spinal cord synaptic transmission, and central sensitization. TLR3 may serve as a new target for developing anti-itch treatment. PMID:22565312
A Picture You Can Handle: Infants Treat Touch-Screen Images More Like Photographs than Objects.
Ziemer, Christine J; Snyder, Makenna
2016-01-01
Infants actively explore their world in order to determine the different ways in which they can interact with various objects. Although research on infant perception has focused on how infants understand the differences between 2- and 3-dimensional objects, today's infants increasingly encounter 2D images with interactive qualities on smart-phone screens, tablets, and laptops. The purpose of this experiment was to examine the types of manual behaviors infants direct toward tablet images and to compare these actions to those evoked by 2D photographs or 3D when tactile feedback is controlled. Infants between the ages of 7-10 months sat on their parent's lap in front of a table with a built-in well covered by a clear, plastic sheet while the three types of displays (photographs, objects, and screen images on a tablet) were presented for 30 s each. Infants saw three examples of each type of display presented in the built-in well so that tactile feedback information from the different displays was controlled. Coders noted the proportion of trials in which infants grasped, scratched, rubbed, or patted the display. Results indicate that infants direct significantly more grasps, scratches, and rubs toward 3D objects than 2D photographs. Infants also direct more grasps to objects compared to screen images. Our data suggests that infants are treating screen images more similarly to 2D photographs than 3D objects.
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.
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.
Opioid and neurokinin activities of substance P fragments and their analogs.
Lei, S Z; Lipkowski, A W; Wilcox, G L
1991-02-07
Newly developed substance P (SP) analogs with altered N-terminal sequences which equalize the lipophilicity of the N-terminal and C-terminal elements and of their fusion product were examined using i.t. injection in mice. I.t. injection of either the full length analog or the C-terminal hexapeptide (CP) produced biting and scratching behavior similar to that elicited by SP. SPF was approximately 5-fold and CP 14-fold less potent than native SP. The N-terminal peptide (NP) was inactive by itself but inhibited CP-elicited behavior. Naloxone antagonized this action of NP and shifted the SPF dose-response curve 4-fold to the left. However, naloxone had no effect on the action of CP or on the action of any of the native neurokinins. The results are consistent with the hypothesis that N- and C-terminal analogs of SP can have opioid and SP-like actions, respectively, in the CNS of rodents. Furthermore, analogs of SP which include at least the terminal tetrapeptide retain neurokinin activity.
Collective behavior of brain tumor cells: The role of hypoxia
NASA Astrophysics Data System (ADS)
Khain, Evgeniy; Katakowski, Mark; Hopkins, Scott; Szalad, Alexandra; Zheng, Xuguang; Jiang, Feng; Chopp, Michael
2011-03-01
We consider emergent collective behavior of a multicellular biological system. Specifically, we investigate the role of hypoxia (lack of oxygen) in migration of brain tumor cells. We performed two series of cell migration experiments. In the first set of experiments, cell migration away from a tumor spheroid was investigated. The second set of experiments was performed in a typical wound-healing geometry: Cells were placed on a substrate, a scratch was made, and cell migration into the gap was investigated. Experiments show a surprising result: Cells under normal and hypoxic conditions have migrated the same distance in the “spheroid” experiment, while in the “scratch” experiment cells under normal conditions migrated much faster than under hypoxic conditions. To explain this paradox, we formulate a discrete stochastic model for cell dynamics. The theoretical model explains our experimental observations and suggests that hypoxia decreases both the motility of cells and the strength of cell-cell adhesion. The theoretical predictions were further verified in independent experiments.
Automated simulation as part of a design workstation
NASA Technical Reports Server (NTRS)
Cantwell, Elizabeth; Shenk, T.; Robinson, P.; Upadhye, R.
1990-01-01
A development project for a design workstation for advanced life-support systems (called the DAWN Project, for Design Assistant Workstation), incorporating qualitative simulation, required the implementation of a useful qualitative simulation capability and the integration of qualitative and quantitative simulation such that simulation capabilities are maximized without duplication. The reason is that to produce design solutions to a system goal, the behavior of the system in both a steady and perturbed state must be represented. The Qualitative Simulation Tool (QST), on an expert-system-like model building and simulation interface toll called ScratchPad (SP), and on the integration of QST and SP with more conventional, commercially available simulation packages now being applied in the evaluation of life-support system processes and components are discussed.
Dynamics of solid lubrication as observed by optical microscopy
NASA Technical Reports Server (NTRS)
Sliney, H. E.
1976-01-01
A bench metallograph was converted into a micro contact imager by the addition of a tribometer employing a steel ball in sliding contact with a glass disk. The sliding contact was viewed in real time by means of projection microscope optics. The dynamics of abrasive particles and of solid lubricant particles within the contact were observed in detail. The contact was characterized by a constantly changing pattern of elastic strain with the passage of surface discontinuities and solid particles. Abrasive particles fragmented upon entering the contact, embedded in one surface and scratched the other; in contrast, the solid lubricant particles flowed plastically into thin films. The rheological behavior of the lubricating solids gave every appearance of a paste-like consistency within the Hertzian contact.
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.
Skin tests of pollen grains of taxodiaceae and cupressaceae in children with bronchial asthma.
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.
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.
IL-6 as a corneal wound healing mediator in an in vitro scratch assay.
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.
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.
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.
Husky, Mathilde M; Michel, Grégory; Richard, Jean-Baptiste; Guignard, Romain; Beck, François
2015-06-01
The objectives of the present study are to describe gender differences in factors associated with moderate risk and problem gambling. Data were extracted from the 2010 Health Barometer, a large survey on a representative sample of the general population aged 15-85 years living in France (n=27,653), carried out by the National Institute for Health Promotion and Health Education. Data were collected between October 2009 and July 2010. A computer-assisted telephone interview system was used. The findings indicate that men are three times more likely to experience problems with gambling. Men and women have different patterns of gambling activities. Men were more involved with Rapido, internet gambling, sports and racetrack betting, poker, and casino tables, whereas women gambled more often on scratch games. Both men and women engaging in immediate reward games were significantly more likely to experience difficulties with gambling. This association, however, was stronger in women. Furthermore, suicidal ideation and behaviors were more likely to be associated with gambling problems in women as compared to men. The study underscores the importance of considering gender-related differences in the study of gambling behaviors. Copyright © 2015 Elsevier Ltd. All rights reserved.
Godara, A; Raabe, D; Green, S
2007-03-01
The effect of sterilization on the structural integrity of the thermoplastic matrix composite polyetheretherketone (PEEK) reinforced with carbon fibers (CF) is investigated by nanoindentation and nanoscratch tests. The use of the material as a medical implant grade requires a detailed understanding of the micromechanical properties which primarily define its in vivo behavior. Sterilization is a mandatory process for such materials used in medical applications like bone implants. The steam and gamma radiation sterilization processes employed in this study are at sufficient levels to affect the micromechanical properties of some polymer materials, particularly in the interphase region between the polymer matrix and the reinforcing fibers. Nanoindentation and nanoscratch tests are used in this work to reveal local gradients in the hardness and the elastic properties of the interphase regions. Both methods help to explore microscopic changes in the hardness, reduced stiffness and scratch resistance in the interphase region and in the bulk polymer matrix due to the different sterilization processes employed. The results reveal that neither steam nor gamma radiation sterilization entails significant changes of the reduced elastic modulus, hardness or coefficient of friction in the bulk polymer matrix. However, minor material changes of the PEEK matrix were observed in the interphase region. Of the two sterilization methods used, the steam treatment has a more significant influence on these small changes in this region and appears to increase slightly the thickness of the interphase zone.
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.
A possible role for CD26/DPPIV enzyme activity in the regulation of psoriatic pruritus.
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.
AQP5 is differentially regulated in astrocytes during metabolic and traumatic injuries.
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.
Application of a model of instrumental conditioning to mobile robot control
NASA Astrophysics Data System (ADS)
Saksida, Lisa M.; Touretzky, D. S.
1997-09-01
Instrumental conditioning is a psychological process whereby an animal learns to associate its actions with their consequences. This type of learning is exploited in animal training techniques such as 'shaping by successive approximations,' which enables trainers to gradually adjust the animal's behavior by giving strategically timed reinforcements. While this is similar in principle to reinforcement learning, the real phenomenon includes many subtle effects not considered in the machine learning literature. In addition, a good deal of domain information is utilized by an animal learning a new task; it does not start from scratch every time it learns a new behavior. For these reasons, it is not surprising that mobile robot learning algorithms have yet to approach the sophistication and robustness of animal learning. A serious attempt to model instrumental learning could prove fruitful for improving machine learning techniques. In the present paper, we develop a computational theory of shaping at a level appropriate for controlling mobile robots. The theory is based on a series of mechanisms for 'behavior editing,' in which pre-existing behaviors, either innate or previously learned, can be dramatically changed in magnitude, shifted in direction, or otherwise manipulated so as to produce new behavioral routines. We have implemented our theory on Amelia, an RWI B21 mobile robot equipped with a gripper and color video camera. We provide results from training Amelia on several tasks, all of which were constructed as variations of one innate behavior, object-pursuit.
Tribological and Rheological Properties of a Synovial Fluid Model
NASA Astrophysics Data System (ADS)
Klossner, Rebecca; Liang, Jing; Krause, Wendy
2010-03-01
Hyaluronic acid (HA) and the plasma proteins, albumin and globulins, are the most abundant macromolecules in synovial fluid, the fluid that lubricates freely moving joints. In previous studies, bovine synovial fluid, a synovial fluid model (SFM) and albumin in phosphate buffered saline (PBS) were observed to be rheopectic---viscosity increases over time under constant shear. Additionally, steady shear experiments have a strong shear history dependence in protein-containing solutions, whereas samples of HA in PBS behaved as a ``typical'' polyelectrolyte. The observed rheopexy and shear history dependence are indicative of structure building in solution, which is most likely caused by protein aggregation. The tribology of the SFM was also investigated using nanoindenter-based scratch tests. The coefficient of frictions (μ) between the diamond nanoindenter tip and a polyethylene surface was measured in the presence of the SFM and solutions with varied protein and HA concentrations. The lowest μ is observed in the SFM, which most closely mimics a healthy joint. Finally, an anti-inflammatory drug, hydroxychloroquine, was shown to inhibit protein interactions in the SFM in rheological studies, and thus the tribological response was examined. We hypothesize that the rheopectic behavior is important in lubrication regimes and therefore, the rheological and tribological properties of these solutions will be correlated.
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.
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
Peripheral gabapentin regulates mosquito allergy-induced itch in mice.
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.
Factors affecting the outcome of "endometrial scratch" in women with recurrent implantation failure.
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.
Regenerative responses after mild heart injuries for cardiomyocyte proliferation in zebrafish
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
Hou, Min; Tang, Qing; Xue, Qiang; Zhang, Xiaona; Liu, Yang; Yang, Sheng; Chen, Liechun; Xu, Xiaoyu
2017-01-04
Du Liang soft capsule (DL) is a traditional Chinese medicine for treating migraines; it is made from two Chinese herbs, including LigusticumstriatumDC., root; Angelica dahurica (Hoffm.) Benth. & Hook.f. ex Franch. & Sav., root. In the present study, we aimed to elucidate the pharmacodynamic action of DL and its mechanism in an animal model of migraines induced by glyceryl trinitrate (GTN). Sixty rats were randomly divided into six groups, including a normal control group, model control group, positive group (Sumatriptan 0.006gkg -1 ), and three DL groups (0.44, 1.31 and 3.93gkg -1 ). All rats were intragastrically treated with the corresponding treatment for 7 consecutive days, and they were subcutaneously injected with GTN (10mgkg -1 ) 30min after the last treatment, except in the normal control group. After model establishment, the behaviors of all rats, including head scratching, cage climbing, and the development of red ears were observed continuously by digital camera every 30min for 3h. Four hours after GTN treatment, all rats were anaesthetized and the blood and tissue samples were collected. Plasma calcitonin gene related to peptide (CGRP) and endothelin (ET) levels were measured using the radioimmunoassay method, and serum NO was determined by the colorimetric method. Afterwards, the brainstem tissues were dissected and washed with physiological saline, and divided evenly into two parts. One part was used to test the monoamine levels, including levels of 5-hydroxytryptamine (5-HT), norepinephrine (NE) and dopamine (DA), by the fluorometric method, and the other part was used to determine the nuclear factor kappaB (NF-κB) p65, nuclear c-fos, inducible nitric oxide synthase (iNOS), interleukin (IL)-1β (IL-1β), and cyclooxygenase-2 (COX-2) levels by Western blot analysis. In the pharmacodynamic action assay, DL (1.31 and 3.93gkg -1 ) greatly improved the abnormal behaviors of migraine rats, including head scratching and cage climbing, and the development of red ears. In the mechanism assay, compared with the control group, the plasma CGRP and serum NO levels and the brainstem 5-HT, NE and DA levels in the DL administration groups were significantly decreased; and the plasma ET levels were remarkably increased. Moreover, down-regulation of NF-κB p65, c-fos and pro-inflammatory cytokines, including iNOS, IL-1β and COX-2 in the brainstem in the DL administration groups were observed by Western blot analysis. The above results suggested that DL has a therapeutic effect on migraines, and its mechanism may be related to adjusting the level of neurotransmitters and vasoactive substances, consequently relieving neurogenic inflammation. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Facilitation of TRPV4 by TRPV1 is required for itch transmission in some sensory neuron populations
Kim, Seungil; Barry, Devin M.; Liu, Xian-Yu; Yin, Shijin; Munanairi, Admire; Meng, Qing-Tao; Cheng, Wei; Mo, Ping; Wan, Li; Liu, Shen-Bin; Ratnayake, Kasun; Zhao, Zhong-Qiu; Gautam, Narasimhan; Zheng, Jie; Ajith Karunarathne, W. K.; Chen, Zhou-Feng
2017-01-01
The transient receptor potential channels (TRPs) respond to chemical irritants and temperature. TRPV1 responds to the itch-inducing endogenous signal histamine, and TRPA1 responds to the itch-inducing chemical chloroquine. We showed that, in sensory neurons, TRPV4 is important for both chloroquine-and histamine-induced itch and that TRPV1 has a role in chloroquine-induced itch. Chloroquine-induced scratching was reduced in mice in which TRPV1 was knocked down or pharmacologically inhibited. Both TRPV4 and TRPV1 were present in some sensory neurons. Pharmacological blockade of either TRPV4 or TRPV1 significantly attenuated the Ca2+ response of sensory neurons exposed to histamine or chloroquine. Knockout of Trpv1 impaired Ca2+ responses and reduced scratching behavior evoked by a TRPV4 agonist, whereas knockout of Trpv4 did not alter TRPV1-mediated capsaicin responses. Electrophysiological analysis of human embryonic kidney (HEK) 293 cells coexpressing TRPV4 and TRPV1 revealed that the presence of both channels enhanced the activation kinetics of TRPV4 but not of TRPV1. Biochemical and biophysical studies suggested a close proximity between TRPV4 and TRPV1 in dorsal root ganglion neurons and in cultured cells. Thus, our studies identified TRPV4 as a channel that contributes to both histamine- and chloroquine-induced itch and indicated that the function of TRPV4 in itch signaling involves TRPV1-mediated facilitation. TRP facilitation through the formation of heteromeric complexes could be a prevalent mechanism by which the vast array of somatosensory information is encoded in sensory neurons. PMID:27436359
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.
Cortico-subcortical activation patterns for itch and pain imagery.
Mochizuki, Hideki; Baumgärtner, Ulf; Kamping, Sandra; Ruttorf, Michaela; Schad, Lothar R; Flor, Herta; Kakigi, Ryusuke; Treede, Rolf-Detlef
2013-10-01
The imagery of itch and pain evokes emotional responses and covert motor responses (scratching to itch and withdrawal to pain). This suggests some similarity in cerebral mechanisms. However, itch is more socially contagious than pain, as evidenced by the fact that scratching behaviors can be easily initiated by watching itch-inducing situations, whereas withdrawal is less easily initiated by watching painful situations. Thus, we assumed that the cerebral mechanisms of itch imagery partly differ from those of pain imagery in particular with respect to motor regions. We addressed this issue in 18 healthy subjects using functional magnetic resonance imaging. The subjects were instructed to imagine itch and pain sensations in their own bodies while viewing pictures depicting stimuli associated with these sensations. Itch and pain imagery activated the anterior insular cortex (aIC) and motor-related regions such as supplementary motor area, basal ganglia, thalamus, and cerebellum. Activity in these regions was not significantly different between itch and pain imagery. However, functional connectivity between motor-related regions and the aIC showed marked differences between itch and pain imagery. Connectivity with the aIC was stronger in the primary motor and premotor cortices during pain imagery and stronger in the globus pallidus during itch imagery. These findings indicate that brain regions associated with imagery of itch are the same as those involved in imagery of pain, but their functional networks differ. These differences in brain networks may explain why motor responses to itch are more socially contagious than those related to pain. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
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.
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.
Cat-scratch disease and bone scintigraphy.
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.
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.
[Cat-scratch disease with bone compromise: atypical manifestation].
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.
Weszl, Miklós; Tóth, Krisztián László; Kientzl, Imre; Nagy, Péter; Pammer, Dávid; Pelyhe, Liza; Vrana, Nihal E; Scharnweber, Dieter; Wolf-Brandstetter, Cornelia; Joób F, Árpád; Bognár, Eszter
2017-09-01
The objective of this study was to investigate the reproducibility, mechanical integrity, surface characteristics and corrosion behavior of nanotubular (NT) titanium oxide arrays in comparison with a novel nano-pitted (NP) anodic film. Surface treatment processes were developed to grow homogenous NT and NP anodic films on the surface of grade 2 titanium discs and dental implants. The effect of process parameters on the surface characteristics and reproducibility of the anodic films was investigated and optimized. The mechanical integrity of the NT and NP anodic films were investigated by scanning electron microscopy, surface roughness measurement, scratch resistance and screwing tests, while the chemical and physicochemical properties were investigated in corrosion tests, contact angle measurement and X-ray photoelectron spectroscopy (XPS). The growth of NT anodic films was highly affected by process parameters, especially by temperature, and they were apt to corrosion and exfoliation. In contrast, the anodic growth of NP film showed high reproducibility even on the surface of 3-dimensional screw dental implants and they did not show signs of corrosion and exfoliation. The underlying reason of the difference in the tendency for exfoliation of the NT and NP anodic films is unclear; however the XPS analysis revealed fluorine dopants in a magnitude larger concentration on NT anodic film than on NP surface, which was identified as a possible causative. Concerning other surface characteristics that are supposed to affect the biological behavior of titanium implants, surface roughness values were found to be similar, whereas considerable differences were revealed in the wettability of the NT and NP anodic films. Our findings suggest that the applicability of NT anodic films on the surface of titanium bone implants may be limited because of mechanical considerations. In contrast, it is worth to consider the applicability of nano-pitted anodic films over nanotubular arrays for the enhancement of the biological properties of titanium implants. Copyright © 2017 Elsevier B.V. All rights reserved.
[A new machinability test machine and the machinability of composite resins for core built-up].
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.
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.
Protein contact dermatitis: allergens, pathogenesis, and management.
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.
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.
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.
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.
Li, Jiefu; Zhang, Wei; Guo, Zhenhao; Wu, Sophia; Jan, Lily Yeh; Jan, Yuh-Nung
2016-11-02
Mechanosensation, one of the fastest sensory modalities, mediates diverse behaviors including those pertinent for survival. It is important to understand how mechanical stimuli trigger defensive behaviors. Here, we report that Drosophila melanogaster adult flies exhibit a kicking response against invading parasitic mites over their wing margin with ultrafast speed and high spatial precision. Mechanical stimuli that mimic the mites' movement evoke a similar kicking behavior. Further, we identified a TRPV channel, Nanchung, and a specific Nanchung-expressing neuron under each recurved bristle that forms an array along the wing margin as being essential sensory components for this behavior. Our electrophysiological recordings demonstrated that the mechanosensitivity of recurved bristles requires Nanchung and Nanchung-expressing neurons. Together, our results reveal a novel neural mechanism for innate defensive behavior through mechanosensation. We discovered a previously unknown function for recurved bristles on the Drosophila melanogaster wing. We found that when a mite (a parasitic pest for Drosophila) touches the wing margin, the fly initiates a swift and accurate kick to remove the mite. The fly head is dispensable for this behavior. Furthermore, we found that a TRPV channel, Nanchung, and a specific Nanchung-expressing neuron under each recurved bristle are essential for its mechanosensitivity and the kicking behavior. In addition, touching different regions of the wing margin elicits kicking directed precisely at the stimulated region. Our experiments suggest that recurved bristles allow the fly to sense the presence of objects by touch to initiate a defensive behavior (perhaps analogous to touch-evoked scratching; Akiyama et al., 2012). Copyright © 2016 the authors 0270-6474/16/3611275-08$15.00/0.
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.
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.
Six fatal cases of classical rabies virus without biting incidents, Iran 1990-2010.
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.
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.
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.
Brain Processing of Contagious Itch in Patients with Atopic Dermatitis
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
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.
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
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
NASA Astrophysics Data System (ADS)
Xu, Jiang; Sun, Teng Teng; Jiang, Shuyun; Munroe, Paul; Xie, Zong-Han
2018-07-01
In this investigation, a MoO3-SiO2 nanocomposite coating was developed on a 316L stainless steel (SS) substrate by double-cathode glow discharge deposition. Chemical valence states, phase composition and microstructure features of the nanocomposite coating were studied using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was found that the nanocomposite coating was composed of a mixture of crystalline MoO3 and amorphous phases, in which amorphous SiO2 phase was embedded between the hexagonal-structured MoO3 grains with an average grain size of ∼8.4 nm. Nanoindentation and scratch tests, together with SEM and TEM observation of locally deformed regions, indicated that the nanocomposite coating exhibited high load-bearing capacity due to a combination of high hardness and good adhesion. Contact angle measurements suggested that the nanocomposite coating was more hydrophobic than uncoated 316L SS. The anti-bacterial activity of the MoO3-SiO2 nanocomposite coating against two bacterial strains (E. coli and S. aureus) was determined by the spread plate method. This showed that both bacterial strains exposed to the coating suffered a significant loss of viability. The influences of sulfate-reducing bacteria (SRB) on the electrochemical behavior of the MoO3-SiO2 nanocomposite coating in modified Postgate's C seawater (PCS) medium were investigated through potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The electrochemical tests revealed that the coating had a greater resistance to microbiologically influenced corrosion induced by SRB than uncoated 316L SS. This was corroborated by electrochemical testing (potentiodynamic polarization and EIS), in conjunction with SEM observations of the corroded surfaces.
Asymmetry of righting reflexes in sea turtles and its behavioral correlates.
Malashichev, Yegor
2016-04-01
The righting responses, when the animal rights itself over one side of the body after been overturned on the back, are one of the simplest ways to test for laterality, especially in lower vertebrates. In anuran amphibians unilateral preferences in righting responses correlated to the degree of the use of alternating-limb (asynchronous) movements during locomotion. Turtles is one of the underrepresented vertebrate groups in the studies of laterality, while possess also different types of locomotion (with synchronous or asynchronous use of the contralateral limbs), which allows testing the hypothesis on functional relationship between the mode of locomotion and the strength of laterality. We studied two species of sea turtles, Green turtle (Chelonia mydas) and Olive Ridley turtle (Lepidochelys olivacea), which differ from the majority of other representatives of the order in that they mostly utilize synchronous locomotion, when all four limbs move simultaneously in strokes (scratching). In righting response tests turtles demonstrated individual and weak population level laterality, which differed in strength. The Green turtle was less lateralized with the majority of individuals being ambipreferent. The Olive Ridley turtle had a greater number of lateralized individuals and a greater average strength of laterality. Interspecies comparison to land tortoises, which use only asynchronous (alternating-limb) walking (crawling), confirmed the rule found in amphibians: the more asynchronous locomotion is used, the greater is the strength of laterality in righting. Hence, data from turtles and amphibians may represent a phenomenon common for all quadruped vertebrates. We also discuss possible biomechanical and neurological correlates of this evolutionary change in locomotory patterns and lateralization in sea turtles when adapting to sea life. Copyright © 2016 Elsevier Inc. All rights reserved.
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
Judge, P G; Griffaton, N S; Fincke, A M
2006-10-01
Primates change a variety of behavioral responses during short-term exposure to crowding. Under crowded conditions, rates of aggression, submissive behavior, and affiliative behavior may increase or decrease. Different patterns of change among these three categories of response have been interpreted as various coping "strategies" for managing the increased risk of conflict under crowded conditions. Grooming is of particular interest because this behavior is known to have a calming influence on the recipient and could be used to manage conflict under tense situations. A captive group of nine hamadryas baboons (Papio hamadryas hamadryas) composed of two harems was observed under short-term crowding to determine whether this species adopts conflict-management strategies similar to those described in other primates. The aggression, submission, affiliation, and displacement activities of the six adults in the group (two males and four females) were recorded, and behaviors in their small indoor quarters was compared with baseline behaviors in the outdoor section of their enclosure, which had over 10 times more space. Repeated-measures analysis of variance (ANOVA) was used to compare behavioral rates during crowding with baseline rates recorded immediately after crowding and during matched controls collected at the same time of day as the crowding sessions. Aggression and submission rates did not change significantly across conditions. Huddling together and proximity increased during crowding, and females increased grooming of their harem male during crowding. Displacement activities (e.g., pacing and self-grooming) increased during crowding, but scratching, an indicator of anxiety in primates, did not. The pattern of behavior exhibited by this group conforms to an active "tension-reduction" strategy in which animals successfully reduce the higher risk of aggression during crowding.
Fox-Rabinovich, German; Locks Junior, Edinei; Stolf, Pietro; Matos Martins, Marcelo
2018-01-01
In the aluminum die casting process, erosion, corrosion, soldering, and die sticking have a significant influence on tool life and product quality. A number of coatings such as TiN, CrN, and (Cr,Al)N deposited by physical vapor deposition (PVD) have been employed to act as protective coatings due to their high hardness and chemical stability. In this study, the wear performance of two nanocomposite AlTiN and AlCrN coatings with different structures were evaluated. These coatings were deposited on aluminum die casting mold tool substrates (AISI H13 hot work steel) by PVD using pulsed cathodic arc evaporation, equipped with three lateral arc-rotating cathodes (LARC) and one central rotating cathode (CERC). The research was performed in two stages: in the first stage, the outlined coatings were characterized regarding their chemical composition, morphology, and structure using glow discharge optical emission spectroscopy (GDOES), scanning electron microscopy (SEM), and X-ray diffraction (XRD), respectively. Surface morphology and mechanical properties were evaluated by atomic force microscopy (AFM) and nanoindentation. The coating adhesion was studied using Mersedes test and scratch testing. During the second stage, industrial tests were carried out for coated die casting molds. In parallel, tribological tests were also performed in order to determine if a correlation between laboratory and industrial tests can be drawn. All of the results were compared with a benchmark monolayer AlCrN coating. The data obtained show that the best performance was achieved for the AlCrN/Si3N4 nanocomposite coating that displays an optimum combination of hardness, adhesion, soldering behavior, oxidation resistance, and stress state. These characteristics are essential for improving the die mold service life. Therefore, this coating emerges as a novelty to be used to protect aluminum die casting molds. PMID:29495620
Cat-Scratch Disease: A Pitfall for Lymphoma Evaluation by FDG-PET/CT.
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.
Improvement of Scratch and Wear Resistance of Polymers by Fillers Including Nanofillers
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
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.