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Adhesive
Kinds of Adhesive Terms modified by Adhesive Selected AbstractsSELF-ETCH ADHESIVES FOR SEALANTS?JOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 2 2007PhD Guest Expert, Robert J. Feigal DDS [source] INFLUENCE OF CAVITY CONFIGURATION ON MICROLEAKAGE AROUND CLASS V RESTORATIONS BONDED WITH SEVEN SELF-ETCHING ADHESIVESJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 2 2004Jorge Perdigăo DMD [source] Parabolic flight primes cytotoxic capabilities of polymorphonuclear leucocytes in humansEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 8 2009I. Kaufmann Abstract Background, Previously performed in vitro studies suggested that gravitational stress may alter functions of immune cells. This study investigated the in vivo effects of parabolic flight manoeuvres as a short-term model of micro- and hypergravity on the cytotoxic and microbicidal polymorphonuclear leucocyte (PMN) functions as the key element of innate immunity. Material and methods, Twenty-one healthy male volunteers underwent 30 subsequent parabolic flight manoeuvres. Each manoeuvre produced 22-s periods of nearly weightlessness close to «0g», with each parabola starting with a pull-up and ending with a pull-out (hypergravity) at 1·8 g for about 20 s each. Blood samples were drawn 24 h prior to take off (T0), after 25,30 parabolas (T1), and 24 h (T2) and 48 h (T3) after flight for determination of (i) leucocyte number and subpopulations, (ii) PMNs' capabilities to produce hydrogen peroxide (H2O2) and to adhere and phagocytose particles and (iii) plasma cytokines known to prime PMN functions [interleukin-8 (IL-8), tumour necrosis factor-, (TNF-,), granulocyte-colony stimulating factor (G-CSF) and granulocyte-macrophage colony stimulating factor (GM-CSF)]. Results, Parabolic flight induced an increase in leucocyte number with a significant elevation of the PMN fraction. The spontaneous H2O2 production by PMNs did not change; however, the capability of PMNs to produce H2O2 in response to soluble stimuli [N -formyl-methionyl-leucyl-phenylalanine (fMLP), fMLP and TNF-,, calcium ionophore (A23187), phorbol myristate acetate (PMA)] was increased. Adhesive and phagocytic properties of PMNs were not altered. Regarding priming cytokines, IL-8 and G-CSF were significantly elevated. Conclusions, Our data indicate that parabolic flight induces priming of the cytotoxic capabilities of PMNs without affecting microbicidal functions. [source] Evaluation of effects of rofecoxib on platelet function in an in vitro model of thrombosis with circulating human bloodEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 4 2004M. R. Hernandez Abstract Background, Cyclooxygenase (COX)-2-selective non-steroidal anti-inflammatory drugs have been used for anti-inflammatory therapy. However, it has also been described that they may increase risk of cardiovascular events. Objectives, To study the effects of COX2 inhibitor rofecoxib on platelet function using in vitro tests. Results were compared with those obtained in a parallel experiment with acetyl salicylic acid (ASA). Methods, Studies of platelet aggregation, using different agonists, were performed by a turbidimetric method. Adhesive and cohesive function of platelets were analyzed by perfusion techniques, treated blood was exposed to thrombogenic surfaces and platelet interaction was morphometrically evaluated. Results, Twenty-five µM of rofecoxib induced a prolonged lag time and a reduction in the percentage of aggregation when arachidonic acid, ADP or collagen were used as agonists. In perfusion studies with parallel chamber rofecoxib 50 µM and ASA 500 µM reduced overall platelet interaction with the collagen surface (17·4 ± 3·7, P < 0·05; vs. 32·1 ± 2·6%P < 0·05 and 17·9 ± 2·4, vs. 31·9 ± 3·24, P < 0·05, respectively). In studies performed on annular chambers, 25 µM of rofecoxib reduced platelet interaction; values of the thrombus and covered surface were 17·4 ± 4·5%; P < 0·05 and 21·1 ± 4·1%; P < 0·05, respectively, vs. 30·4 ± 7·5% and 33·5 ± 6·5 in the control. ASA did also impair thrombus formation but differences did not reach the levels of statistical significance. Moreover, rofecoxib but not ASA reduced significantly thrombus height and thrombus area (7·4 ± 0·5 µM; P < 0·005 and 96·0 ± 21·2 µM2; P < 0·05 vs. control 11·2 ± 0·9 µM and 220·0 ± 47·7µM2, respectively). Conclusion, We conclude that under our experimental conditions, rofecoxib diminished platelet aggregation induced by different agonists and inhibited platelet-mediated thrombogenesis in an in vitro model of thrombosis. [source] Adhesive, Flexible, and Robust Polysaccharide Nanosheets Integrated for Tissue-Defect RepairADVANCED FUNCTIONAL MATERIALS, Issue 16 2009Toshinori Fujie Abstract Recent developments in nanotechnology have led to a method for producing free-standing polymer nanosheets as a macromolecular organization. Compared with bulk films, the large aspect ratio of such nanosheets leads to unique physical properties, such as transparency, noncovalent adhesion, and high flexibility. Here, a biomedical application of polymer nanosheets consisting of biocompatible and biodegradable polysaccharides is reported. Micro-scratch and bulge tests indicate that the nanosheets with a thickness of tens of nanometers have sufficient physical adhesiveness and mechanical strength for clinical use. A nanosheet of 75,nm thickness, a critical load of 9.1,×,104,N m,1, and an elastic modulus of 9.6,GPa is used for the minimally invasive repair of a visceral pleural defect in beagle dogs without any pleural adhesion caused by wound repair. For the first time, clinical benefits of sheet-type nano-biomaterials based on molecular organization are demonstrated, suggesting that novel therapeutic tools for overlapping tissue wounds will be possible without the need for conventional surgical interventions. [source] Polymeric Nanohairs: Stooped Nanohairs: Geometry-Controllable, Unidirectional, Reversible, and Robust Gecko-like Dry Adhesive (Adv. Mater.ADVANCED MATERIALS, Issue 22 200922/2009) Kahp Suh, Hong Lee, and co-workers present on p. 2276 a simple, yet robust method for fabricating an array of stooped "nanohairs" by applying a proper choice of materials and post e-beam exposure, even for an aspect ratio of 10. The stooped nanohairs possess the unidirectional feature of frictional adhesion with a remarkably high adhesion force (,11 N cm,2). [source] Stooped Nanohairs: Geometry-Controllable, Unidirectional, Reversible, and Robust Gecko-like Dry AdhesiveADVANCED MATERIALS, Issue 22 2009Tae-il Kim A simple yet robust method to fabricate an array of stooped nanohairs is presented, with a proper choice of material and post e-beam exposure even for an aspect ratio of 10. The stooped nanohairs have the unidirectional feature of frictional adhesion with a remarkably high adhesion force (,11,N cm,2). [source] A Gecko-Inspired Reversible Adhesive,ADVANCED MATERIALS, Issue 20 2008Michael T. Northen A synthetic, fully reversible, switchable, gecko-inspired adhesive is presented. The biomimetic system is composed of flexible nickel paddles coated with aligned vertical polymeric nanorods. When subjected to a magnetic field, adhesion decreases by a factor of 40. The ability of the adhesive to controllably stick and release from a surface could enable technologies from ubiquitous latching systems to climbing microrobotics. [source] The Effect of Dowel Space on the Bond Strengths of Fiber PostsJOURNAL OF PROSTHODONTICS, Issue 3 2007Jorge Perdigăo DMD Purpose: The purpose of this study was to evaluate the effect of the degree of mismatch between post space and post diameters on the bond strength of a fiber-reinforced resin post. Materials and Methods: Thirty-two extracted human maxillary central incisors and canines were endodontically treated and assigned to four groups: Group 1 - Canal prepared with a D.T. Light Post #1 drill (control); Group 2 - Canal prepared with a D.T. Light Post #2 drill; Group 3 - Canal prepared with a D.T. Light Post #3 drill; Group 4 - Canal prepared with a Gates Glidden #6 drill. A D.T. Light Post size 1 was then luted into the canal using One-Step Adhesive and Post Cement Hi-X. A push-out test was performed on three sections of each root to measure push-out bond strengths. Data were analyzed with ANOVA and Bonferroni's test at p < 0.05. Two extra teeth for each group were restored in the same fashion and processed for SEM observation. Results: (in MPa): Group 1: 15.7 ± 6.9; Group 2: 14.7 ± 6.5; Group 3: 14.0 ± 5.0; Group 4: 14.0 ± 5.1. The variable "post space" resulted in no statistically significant difference in mean bond strengths (p > 0.05). For the variable "root region," the coronal third (17.5 ± 6.0) resulted in statistically greater mean bond strengths than the apical third (12.3 ± 6.0) at p < 0.008. The middle third (14.0 ± 5.3) resulted in no statistically significant different mean bond strengths from the coronal third at p > 0.119 and from the apical third at p > 0.999. Under the SEM, some areas of the canal system still displayed residual gutta-percha, which resulted in debonding of the interface between the resin cement and dentin. Areas with incomplete dentin hybridization were observed in localized areas of all groups. Conclusions: The diameter of the post space did not affect the push-out bond strengths. Bonding at the coronal level of the root canal is more reliable than bonding at the apical level. The presence of residual gutta-percha and the deficient dentin hybridization may result in deficient seal of the resin,dentin interface. [source] Automotive Material Sustainability Through Reversible Adhesives,ADVANCED ENGINEERING MATERIALS, Issue 7 2010Allan R. Hutchinson This communication defines the key existing technologies for reversible adhesion and bonded joint disassembly, and introduces the reader to early experimental findings on the use of thermally labile functional additives in an adhesive matrix. These additives have been found to induce localized, out of plane stresses in a joint's bondline, allowing for an adhesive disbond. It has been found that the additive and adhesive matrix combination is key to the relationship between joint disassembly and joint strength. [source] The Dependence between the Process Technologies and the Effect of MAH-PP- Adhesives in Natural Fibre Reinforced Thermoplastic Composites,ADVANCED ENGINEERING MATERIALS, Issue 1-2 2005A. Nechwatal The theoretical possibilities of improving the adhesion between a polypropylene matrix and cellulose natural fibres are well known. However, less is known of how the way of adding MAH-PP products into the composite impacts the adhesion. By comparing mat processes and granule processes this influence on the adhesive effect can be seen. A new process manufacturing natural fibre reinforced granules ( developed in TITK ) was used for these comparisons. It could be shown that the adhesive obviously influences the critical fibre length. [source] Electrogelation for Protein AdhesivesADVANCED MATERIALS, Issue 6 2010Gary G. Leisk Novel electrochemical behavior of silk protein to generate an adhesive electrogel is reported. The biomimetic system demonstrates reversible adhesive properties (see image) and functions on both hydrated and dry surfaces. Further, the system utilizes all-biocompatible components and functions in an all-aqueous process at ambient conditions. Potential applications in medical devices and in environmentally compatible material systems are described. [source] Biomimetic Underwater Adhesives with Environmentally Triggered Setting MechanismsADVANCED MATERIALS, Issue 6 2010Hui Shao Inspired by the sandcastle worm, fluid complex coacervates of polyelectrolytes were formulated as water-borne underwater adhesives. The partially immiscible fluid phase can be delivered underwater and sets into a weight-bearing solid triggered by a change in the pH or temperature. Irreversible hardening occurs through oxidative coupling between catechol and primary amine sidechains. [source] Hierarchical Gecko-Like Adhesives,ADVANCED MATERIALS, Issue 4 2009Christian Greiner The role of hierarchy in gecko-like adhesive surfaces is presented. Experiments on two-level structured surfaces with micropillars of different dimensions demonstrate that hierarchy does not seem to positively influence adhesion of structured surfaces to planar substrates, but may be relevant when stiff materials or rough substrates come into play, where adaptability of the adhesive structure is required for successful contact. [source] Waterborne, Nanocomposite Pressure-Sensitive Adhesives with High Tack Energy, Optical Transparency, and Electrical Conductivity,ADVANCED MATERIALS, Issue 20 2006T. Wang Transparent and conductive pressure-sensitive adhesives are cast from aqueous colloidal dispersions of poly(butyl acrylate) (P(BuA)) and functionalized carbon nanotubes (CNTs). At the percolation threshold for network formation (at only 0.3,wt,% functionalized CNT), the nanotubes remarkably double the amount of strain at adhesive failure and increase the adhesion energy by 85,% (see figure). The tack properties are explained by current models of adhesive debonding. [source] Empirical Modeling of Butyl Acrylate/Vinyl Acetate/Acrylic Acid Emulsion-Based Pressure-Sensitive AdhesivesMACROMOLECULAR MATERIALS & ENGINEERING, Issue 5 2004Renata Jovanovic Abstract Summary: Butyl acrylate/vinyl acetate/acrylic acid (BA/VAc/AA) emulsion latexes were produced in a semi-batch mode. The objective was to generate polymers with properties favoring their application as pressure-sensitive adhesives. The influence of the individual monomer concentrations on final properties such as glass transition temperature (Tg), peel strength, shear strength and tack was investigated. To obtain the maximum amount of information in a reasonable number of runs, a constrained three-component mixture design was used to define the experimental conditions. Latexes were coated onto a polyethylene terephthalate carrier and dried. Different empirical models (e.g. linear, quadratic and cubic mixture models) governing the individual properties (i.e. Tg, peel adhesion, shear resistance and tack) were developed and evaluated. In the given experimental region, no single model was found to fit all of the responses (i.e. the final properties). However, in all models the most significant factor affecting the final properties was the AA concentration, followed by the VAc concentration. Shear strength contour lines over the investigated region. [source] Regulation of a Real-Time Self-Healing Process in Organogel Tissues by Molecular Adhesives,ANGEWANDTE CHEMIE, Issue 36 2010Pritam Mukhopadhyay Dr. Bitte recht freundlich! Thixotrope Prozesse in einem Organogel auf Naphthalendiimid-Basis können mit Rasterkraft- und Transmissionselektronenmikroskopie in Echtzeit verfolgt werden (siehe Bild). Selbstorganisierte 1D-Fasern werden unter mechanischer Belastung abgebaut und während einer Ruhephase durch einen Selbstheilungsprozess wieder zurückgebildet. [source] Adhesives and adhesions: intestinal surgery on a sticky wicket!ANZ JOURNAL OF SURGERY, Issue 12 2004Bruce P. Waxman FRACS No abstract is available for this article. [source] 10 Production and Use of Orchid Adhesives in Aztec Mexico: the Domestic ContextARCHEOLOGICAL PAPERS OF THE AMERICAN ANTHROPOLOGICAL ASSOCIATION, Issue 1 2009Frances F. Berdan First page of article [source] Fractured Teeth Bonded With Dentine Adhesives With And Without Unfilled ResinAUSTRALIAN ENDODONTIC JOURNAL, Issue 2 2002Article first published online: 11 FEB 2010 No abstract is available for this article. [source] In Vivo Study of Wound Bursting Strength and Compliance of Topical Skin AdhesivesACADEMIC EMERGENCY MEDICINE, Issue 12 2008Adam J. Singer MD Abstract Objectives:, Over the past decade, the use of topical skin adhesives (TSA) for wound closure has increased. Among TSA characteristics, strength and flexibility are most important. Prior studies have compared the wound bursting strengths (WBSs) of the cyanoacrylates immediately after wound closure. In this study the authors compared the WBS and flexibility of multiple TSAs immediately and up to 2 days after closure. Methods:, This was a controlled animal experiment. Two-centimeter incisions were created on both sides of 210 Sprague-Dawley rats and randomly closed with one of five commercially available TSAs (Dermabond [D], Indermil [I], Histoacryl [H], Liquiband [L], or GluStitch [G]). WBS and TSA flexibility were measured using the BTC-2000 device immediately after closure and at 1 and 2 days after closure. WBS and TSA flexibility were compared across groups with analysis of variance (ANOVA). Results:, Wound bursting strengths were higher (p < 0.05) at 0, 1, and 2 days for D (274, 388, 232 mm Hg) than for all other TSAs (I 182, 225, and 107; H 189, 214, and 69; L 146, 118, and 75; or G 161, 150, and 73). TSA flexibility was also greater (p < 0.05) at 0, 1, and 2 days for D (36, 27, and 29 mm Hg/mm) than for all other TSAs (I 18, 14, and 12; H 18, 13, and 15; L 19, 14, and 12; G 26, 23, and 18). Conclusions:, The octyl-cyanoacrylate,based adhesive is significantly stronger and more flexible than all the butyl-cyanoacrylate,based adhesives at 0, 1 and 2 days after closure. [source] Patterns of Use of Topical Skin Adhesives in the Emergency DepartmentACADEMIC EMERGENCY MEDICINE, Issue 6 2010Adam J. Singer MD Abstract Objectives:, The objective was to determine patterns of use of topical skin adhesives (TSA) for laceration repair. The authors hypothesized that TSA use would be more common in children and facial lacerations. Methods:, This was a structured retrospective chart review. The setting was a suburban, university-based emergency department (ED) with an emergency medicine (EM) residency; the annual census is 85,000 visits. Charts from consecutive patients presenting with lacerations in the summer of 2008 (June 2008 through August 2008) were reviewed. Demographic, clinical, and wound characteristics were extracted from electronic medical records by trained investigators using structured data collection forms. Characteristics of lacerations repaired with TSA or other closure devices were compared with bivariate and multivariate analyses using odds ratios (ORs) and 95% confidence intervals (CIs). Results:, A total of 755 patients presented to the ED with lacerations over the study period, of whom primary closure was used in 667; nine were excluded because the method of closure was unknown. The most common methods of laceration closure were sutures (485), adhesives (88), and staples (86). Adhesives were used to close 27% of facial lacerations, compared to 4% of all other body locations (difference = 23%, 95% CI = 18% to 29%), and in 20% of pediatric versus 8% of adult lacerations (difference = 13%, 95% CI = 7% to 18%). Adjustment for other potential patient and wound characteristics showed that adhesives were more likely to be used to close facial lacerations (OR = 10.0 CI, 95% CI = 5.5 to 18.0) and lacerations in children (OR = 1.8, 95% CI = 1.1 to 3.0) and less likely to be used as laceration length increased (OR = 0.6, 95% CI = 0.4 to 0.8). Adhesive use was not statistically associated with patient sex or race, laceration edges or shape, or the need for deep sutures. Forty-three percent of adhesive wounds were closed with no anesthetic, and a topical agent was used in another 48%. In contrast, a local anesthetic agent was injected in 87% of sutured wounds (p < 0.001) and 73% of stapled wounds (p < 0.001). Conclusions:, Topical skin adhesives are used more often for children, facial lacerations, and short lacerations. Use of adhesives may improve patient comfort as need for injecting a local anesthetic is reduced. ACADEMIC EMERGENCY MEDICINE 2010; 17:670,672 © 2010 by the Society for Academic Emergency Medicine [source] Twelve-month Sealant Retention in a School-based Program Using a Self-etching Primer/AdhesiveJOURNAL OF PUBLIC HEALTH DENTISTRY, Issue 4 2004Daniel J. Venker DDS ABSTRACT Objectives: Very little independent research has been done on the new self-etching primer/adhesives in dentistry. A recent clinical study compared two sealant application techniques involving self-etching primer adhesives and the traditional phosphoric acid etch. The purpose of this study was to compare these two techniques in an Iowa school-based sealant program. Methods: Twelvemonth sealant retention data on 208 students from the Des Moines, Iowa, school-based sealant program were analyzed retrospectively. Results: Sealant retention reported at the person level showed that 60 percent of the students who received sealants at the five schools had to be recalled at one year to have one or more surfaces reseated. A logistic regression model at the person level demonstrated that the phosphoric acid technique was six times as likely to have retention of all the sealed tooth surfaces as those sealed with Prompt-L-Pop®. Conclusions: In this study, many students had to be recalled to the chair 12 months after sealant application due to incomplete retention. Though sealants were retained in larger numbers with phosphoric acid, overall sealant retention at the tooth level was lower than previously published for clinical studies and school-based programs. Examining retention data at the person level, however, allows program administrators to plan resources more effectively and reevaluate sealant protocol to ensure as few children return for sealant reapplication. [source] The geometry and motion of nematode sperm cellsCYTOSKELETON, Issue 6 2009Evgeny Demekhin Abstract The nematode sperm cell crawls by recycling major sperm protein (MSP) from dimers into subfilaments, filaments, and filament complexes, as a result of thermal writhing in the presence of hydrophobic patches. Polymerization near leading edges of the cell intercolates MSP dimers onto the tips of growing filament complexes, forcing them against the cell boundary, and extending the cytoskeleton in the direction of motion. Strong adhesive forces attach the cell to the substrate in the forward part of the lamellipod, while depolymerization in the rearward part of the cell breaks down the cytoskeleton, contracting the lamellipod and pulling the cell body forward. The movement of these cells, then, is caused by coordinated protrusive, adhesive and contractile forces, spatially separated across the lamellipod. This paper considers a phenomenological model that tracks discrete elements of the cytoskeleton in curvilinear coordinates. The pseudo-two dimensional model primarily considers protrusion and rotation of the cell, along with the evolution of the cell boundary. General assumptions are that pH levels within the lamellipod regulate protrusion, contraction and adhesion, and that growth of the cytoskeleton, over time, is perpendicular to the evolving cell boundary. The model follows the growth and contraction of a discrete number of MSP fiber complexes, since they appear to be the principle contributors for force generation in cell boundary protrusion and contraction, and the backbone for the dynamic geometry and motion. Cell Motil. Cytoskeleton 2009. © 2009 Wiley-Liss, Inc. [source] Cell distribution of stress fibres in response to the geometry of the adhesive environmentCYTOSKELETON, Issue 6 2006Manuel Théry Abstract Cells display a large variety of shapes when plated in classical culture conditions despite their belonging to a common cell type. These shapes are transitory, since cells permanently disassemble and reassemble their cytoskeleton while moving. Adhesive micropatterns are commonly used to confine cell shape within a given geometry. In addition the micropattern can be designed so as to impose cells to spread upon adhesive and nonadhesive areas. Modulation of the pattern geometry allows the analysis of the mechanisms governing the determination of cell shape in response to external adhesive conditions. In this study, we show that the acquisition of cell shape follows two stages where initially the cell forms contact with the micropattern. Here, the most distal contacts made by the cell with the micropattern define the apices of the cell shape. Then secondly, the cell borders that link two apices move so as to minimise the distance between the two apices. In these cell borders, the absence of an underlying adhesive substrate is overcome by stress fibres forming between the apices, which in turn are marked by an accumulation of focal adhesions. By inhibiting myosin function, cell borders on nonadhesive zones become more concave, suggesting that the stress fibres work against the membrane tension in the cell border. Moreover, this suggested that traction forces are unevenly distributed in stationary, nonmigrating, cells. By comparing the stress fibres in cells with one, two, or three nonadherent cell borders it was reasoned that stress fibre strength is inversely proportional to number. We conclude that cells of a given area can generate the same total sum of tractional forces but that these tractional forces are differently spaced depending on the spatial distribution of its adherence contacts. Cell Motil. Cytoskeleton 2006. © 2006 Wiley-Liss, Inc. [source] Use of a cyanoacrylate ester adhesive for splinting of replanted teethDENTAL TRAUMATOLOGY, Issue 6 2008Márcia Regina Negri The long-term clinical and radiographic success of the case reported in this paper indicates that the splinting technique using a quick-setting cyanoacrylate ester adhesive may be a feasible option for making a rapid, simple and efficient contention of replanted teeth in situations where the routinely used materials are not readily available. [source] Multidisciplinary approach of complicated crown fractures of both superior central incisors: a case reportDENTAL TRAUMATOLOGY, Issue 4 2008Anca Silvia Vâlceanu Since the development of the adhesive dentistry, many case reports of crown fractures restored using adhesive reattachment techniques were published. Complex cases, in which more than one tooth are involved, with fractures differing from each other, require specific treatment of each fracture, taking different advantages of the different remaining tooth structures. This case report describes a patient with dissimilar crown fractures of both superior central incisors. After the endodontic treatment, the patient was treated using the combination of several techniques: periodontal surgery (crown lengthening with apically repositioned flap and osseous resective surgery), adhesive technique and cast restoration plus esthetic crown. The periodontal procedure re-created the biologic width and proved to be a reliable adjunctive procedure to the adhesive and the prosthetic techniques used. [source] Captures of the olive fruit fly Bactrocera oleae on spheres of different coloursENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2001Byron I. Katsoyannos Abstract Alighting and capture of wild olive fruit flies, Bactrocera oleae (Rossi) (Diptera, Tephritidae), on spheres of seven different colours was studied on Chios island, Greece. The 70-mm-diam plastic spheres, coated with adhesive, were suspended on olive trees. Yellow and orange spheres trapped the greatest number of males while red and black spheres trapped the greatest number of females. White and blue spheres were the least effective for both sexes. Peak captures occurred in the late afternoon and especially around sunset. Since mating takes place in the last hours of the photophase, the increased captures during that period may be related to the sexual behaviour of the fly. When red spheres were assessed against glass McPhail traps baited with 2% ammonium sulphate, which consist a standard tool for monitoring the olive fruit fly in Greece, there were no significant differences in male captures. However, spheres trapped almost three times as many females as McPhail traps. The possible mechanisms underlying colour discrimination, the motivation of alighting flies and the possible use of red spheres for monitoring and controlling B. oleae are discussed. [source] Role for cAMP-protein kinase A signalling in augmented neutrophil adhesion and chemotaxis in sickle cell diseaseEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 4 2007Andreia A. Canalli Abstract The significance of the leukocyte in sickle cell disease (SCD) pathophysiology is becoming increasingly recognised; we sought to examine whether the chemotactic properties of neutrophils of SCD individuals may be altered and, further, to better understand the signalling events that mediate altered SCD neutrophil function. Adhesion to immobilised fibronectin (FN) and chemotaxis of control and SCD neutrophils were assessed using in vitro static adhesion assays and 96-well chemotaxis chamber assays. Adhesion assays confirmed a significantly higher basal adhesion of SCD neutrophils to FN, compared with control neutrophils. Chemotaxis assays established, for the first time, that SCD neutrophils demonstrate greater spontaneous migration and, also, augmented migration in response to IL-8, when compared with control neutrophils. Co-incubation of SCD neutrophils with KT5720 (an inhibitor of PKA) abrogated increased basal SCD neutrophil adhesion, spontaneous chemotaxis and IL-8-stimulated chemotaxis. Stimulation of SCD neutrophils with IL-8 also significantly augmented SCD neutrophil adhesion to FN with a concomitant increase in cAMP levels and this increase in adhesion was abolished by KT5720. Interestingly, the adhesive properties of neutrophils from SCD individuals on hydroxyurea therapy were not significantly altered and results indicate that a reduction in intracellular cAMP may contribute to lower the adhesive properties of these cells. Data indicate that up-regulated cAMP signalling plays a significant role in the altered adhesive and migratory properties in SCD neutrophils. Such alterations may have important implications for the pathophysiology of the disease and the cAMP-PKA pathway may represent a therapeutic target for the abrogation of altered leukocyte function. [source] Mechanical Characterization of Particulate Aluminum Foams,Strain-Rate, Density and Matrix Alloy versus Adhesive EffectsADVANCED ENGINEERING MATERIALS, Issue 7 2010Dirk Lehmhus Abstract The study evaluates mechanical properties of APM particulate aluminum foams built up from adhesively bonded Al foam spheres. Foams of matrix alloy AlSi10 are compared, with PM AlSi7 foams used as reference. The influence of density is studied both for quasi-static and dynamic compressive loading in a range from ,0.35 to 0.71,g,cm,3. The effect of varying the bonding agent is evaluated for a single density and both strain rate levels by replacing the standard, high-strength epoxy-based adhesive with a polyamide of greatly increased ductility. The result is a clear shift of fracture events to higher strain levels, as well as the introduction of a strain-rate dependency of strength. [source] | |||||||||||||||||||||||||