Shear Bond Strength Of Metallic Brackets Bonded With A New Orthodontic Composite

Aim: The aim of this study was to assess the shear bond strength of orthodontic brackets in different enamel surfaces using the Transbond Plus Color Change composite (TPCC-3M Unitek), and to analyze the Adhesive Remnant Index (ARI). Methods: Seventy-two human premolars were divided into six groups (n = 12), as follows: Group 1(control) Transbond XT conventional; in Groups 2 to 6, TPCC was used under the following enamel treatment conditions: phosphoric acid and XT-primer; Transbond Plus Self-Etching Primer (TPSEP); phosphoric acid only; phosphoric acid, XT-primer and saliva; and TPSEP and saliva, respectively. Twenty-four hours after bonding, the brackets were debonded with an Instron machine at a crosshead speed of 0.5 mm/min, and ARI was evaluated by using a stereoscopic magnifying glass. Results: The mean shear strength values (MPa) for Groups 1 to 6 were 24.6, 18.7, 17.5, 19.7, 17.5 and 14.8, respectively. Data were submitted to ANOVA and Tukey's test (α = 0.05). Group 1 had significantly higher shear bond strength values than Groups 3, 5, and 6 (p 0.05). No statistically significant differences (p > 0.05) were found between Groups 2, 3, 4, 5 and 6. Conclusions: Bracket bonding using TPCC showed adequate adhesion for clinical use, and the type of enamel preparation had no influence.827680Bishara, S.E., VonWald, B.A., Laffoon, J.F., Warren, J.J., The effect of repeated bonding on the shear bond strength of a composite resin orthodontic adhesive (2000) Angle Orthod, 70, pp. 435-441Cal-Neto, J.P., Miguel, J.A.M., An in vivo evaluation of bond failure rates with hydrophilic and self-etching primer systems (2005) J Clin Orthod, 39, pp. 701-702Pandis, N., Polychronopoulou, A., Eliades, T., Failure rate of self-ligating and edgewise brackets bonded with convenvional acid etching and a self-etching primer (2006) Angle Orthod, 76, pp. 119-122Romano, F.L., Correr-Sobrinho, L., Magnani, M.B.B.A., Nouer, D.F., Sinhoretti, M.A.C., Correr, A.B., Shear bond strength of metallic brackets bonded under various enamel conditions (2006) Braz Oral Res, 20 (SPEC ISS), pp. 28-33Grandhi, K., Combe, E.C., Speidel, T.M., Shear bond strength of stainless steel orthodontic brackets with a moisture-insensitive primer (2001) Am J Orthod Dentofacial Orthop, 119, pp. 251-255Sfondrini, M.F., Cacciafesta, V., Scribante, A., De Angelis, M., Klersy, C., Effect of blood contamination on shear bond strength of brackets bonded with conventional and self-etching primers (2004) Am J Orthod Dentofacial Orthop, 125, pp. 357-360Cacciafesta, V., Sfondrini, M.F., De Angelis, M., Scribante, A., Klersy, C., Effect of water and saliva contamination on shear bond strength of brackets bonded with conventional, hydrophilic, and self-etching primers (2003) Am J Orthod Dentofacial Orthop, 123, pp. 633-640Romano, F.L., Tavares, S.W., Consani, S., Magnani, M.B.B.A., Nouer, D.F., Shear bond strength of metallic orthodontic brackets bonded to enamel prepared with self-etching primer (2005) Angle Orthod, 75, pp. 849-853Miller, R.A., Laboratory and clinical evaluation of a self-etching primer (2001) J Clin Orthod, 35, pp. 42-45Dorminey, J.C., Dunn, W.J., Taloumis, L.J., Shear bond strength of orthodontics brackets bonded with a modified 1-step etchant and primer technique (2003) Am J Orthod Dentofacial Orthop, 124, pp. 410-413Grubisa, H.I.S., Heo, G., Raboud, D., Glover, K.E., Major, P.W., An evaluation and comparison of orthodontic bracket bond strengths achieved with self-etching primer (2004) Am J Orthod Dentofacial Orthop, 126, pp. 213-219Vicente, A., Bravo, L.A., Romero, M., Ortiz, A.J., Canteras, M., Shear Bond strength of orthodontic brackets bonded with self-etching primers (2005) Am J Dent, 18, pp. 256-260Noble, R.R., Salas-Lopez, A., English, J.D., Powers, J.M., Clinical evaluation of orthodontic self-etching primers (2006) Texas Dent J., 123, pp. 274-278Turk, T., Elekdag-Turk, S., Isci, D., Effects of self-etching primer on shear bond strength of orthodontic brackets at different debond times (2007) Angle Orthod, 77, pp. 108-112Vicente, A., Bravo, L.A., Shear bond strength of precoated and uncoated brackets using a self-etching primer (2007) Angle Orthod, 77, pp. 524-527Uysal, T., Sisman, A., Can previously bleached teeth be bonded safely using self-etching primer systems? (2008) Angle Orthod, 78, pp. 711-715Artun, J., Bergland, S., Clinical trials with crystal growth conditioning as an alternative to acid-etch enamel pretreatment (1984) Am J Orthod, 85, pp. 333-340Bishara, S.E., Olsen, M., Von Wald, L., Comparisons of shear bond strength of precoated and uncoated brackets (1997) Am J Orthod Dentofacial Orthop, 112, pp. 617-621Buyukyilmaz, T., Usumez, S., Karaman, A.I., Effect of Self-Etching Primers on Bond Strength-Are they Reliable? (2003) Angle Orthod, 73, pp. 64-70Moin, K., Dogon, I.L., Indirect bonding of orthodontic attachments (1977) Am J Orthod, 72, pp. 261-275Jassem, H.A., Retief, D.H., Jamison, H.C., Tensile and shear strengths of bonded and rebounded orthodontic attachments (1981) Am J Orthod, 79, pp. 661-668Prevost, A.P., Fuller, J.L., Peterson, L.C., Use of an intermediate resin in the acid etched procedure: retentive strength, microleakage and failure mod analysis (1982) J Dent Res, 61, pp. 412-418Menezes, L.F.S., Chevitarese, O., Sealant and resin viscosity and their influence on the formation of resin tags (1994) Angle Orthod, 64, pp. 383-388Kula, K.S., Nash, T.D., Purk, J.H., Shear-peel bond strength of orthodontic primer in wet conditions (2003) Orthod Craniofacial Res, 6, pp. 96-100Reynolds, I.R., A review of direct orthodontic bonding (1975) Br J Orthod, 2, pp. 171-17

The effects of conjugated linoleic acid isomers cis-9,trans-11 and trans-10,cis-12 on in vitro bovine embryo production and cryopreservation

Conjugated linoleic acid (CLA) isomers can affect the lipid profile and signaling of cells and thereby alter their function. A total of 5,700 bovine oocytes were used in a structured series of experiments to test the effects of CLA cis-9,trans-11 and CLA trans-10,cis-12 in vitro. In experiment 1, high doses of each CLA isomer during in vitro maturation (IVM) were compared with high or low doses during the entire in vitro culture (IVC) of parthenogenetic embryos. High doses of the CLA isomers ranged from 50 to 200 μM and low doses were 15 and 25 μM. In experiment 2, the low doses of each CLA isomer were tested during IVM/IVC on embryos produced by in vitro fertilization (IVF). Experiment 3 compared the effects of 15 μM doses of each CLA isomer during IVM or IVC of IVF embryos. In experiment 4, post-rewarming survival rates and blastomere counts were assessed for embryos supplemented with each CLA isomer during IVM or for 36 h before vitrification. In experiment 1, when either CLA isomer was provided only during IVM, we observed no effects on overall rates of maturation, cleavage, or blastocysts (92.2 ± 1.6%, 78.3 ± 4.1%, and 28.9 ± 5.1%, respectively). However, high doses of each CLA isomer, but not low doses, during the entire embryo culture period decreased blastocyst rates (5-20%) in a dose-dependent manner. Cleavage rates improved with 15 or 50 μM CLA trans-10,cis-12. Progesterone concentrations in maturation media were significantly increased by high doses of each CLA isomer compared with control, but low doses of CLA isomers had no effect. In experiment 2 with IVF embryos, low doses of each CLA isomer did not alter cleavage rates (average 84.9 ± 1.9%) and only 25 μM CLA trans-10,cis-12 during IVC reduced blastocyst rates below those of controls (25.5 ± 2.1 vs. 38.2 ± 2.3%). The lipid content of embryos was increased and relative expression of the BIRC5 (baculoviral IAP repeat containing 5) gene was depressed by CLA trans-10,cis-12. In experiment 3, low doses (15μM) of each CLA isomer during IVC significantly reduced blastocyst rates (20.6 ± 2.4% and 27.7 ± 1.2% vs. 34.18 ± 1.2% for CLA trans-10,cis-12 and CLA cis-9,trans-11 compared with control, respectively) with less effect of each CLA during IVM. In experiment 4, adding 100 μM CLA cis-9,trans-11 during the final 36 h of culture resulted in a high survival rate after rewarming and culture, and the higher embryo blastomere count was comparable to that of control embryos not undergoing vitrification. In conclusion, supplementation with either CLA isomer did not improve embryo production, but inclusion of CLA cis-9,trans-11 before vitrification improved the quality of bovine IVF embryos after rewarming and culture

Optimizing The Inspection Routine For The Detection Of Electrical Energy Theft In Aes Eletropaulo In São Paulo, Brazil

This work describes the development of a non-invasive and low-cost process that allows for the improvement of the energy theft inspection routine, increasing the field inspection team productivity and reducing the customer's embarrassment in cases where no irregularity is found. This new process is based on the development of an electronic Ah meter device that can be installed on the customer's pole input connections to the power lines. Using the recorded Ah value in the device, it is possible to estimate, within a margin of error, the energy consumption of the customer during a small period, typically one week. This energy value is compared to the customer's regular energy meter reading for the same period. A comprehensive statistical study performed with a database of more than 80000 customers in distribution area of the utility company AES Eletropaulo in São Paulo, Brazil concludes that the comparison between these readings can clearly indicate when tampered or defective meters are found.728089Depuru, S., Wang, L., Devabhaktuni, V., Gudi, N., Measures and setbacks for controlling electricity theft (2010) IEEE North American Power Symposium-NAPS(2009) Bureau for Economic Growth, Agriculture and Trade, , U. S. Agency for International Development Washington, D. C., Transforming Electricity Consumers into Customers: Case Study of a Slum Electrification and Loss Reduction Project in São Paulo, BrazilOnat, N., Transmission and distribution losses of Turkey's power system (2010) Proceedings of the 4th WSEAS Conference on Advances in Energy Planning, Environmental Education and Renewable Energy SourcesSmith, T., Electricity theft comparative analysis (2003) Energy Policy, 32, pp. 2067-2076Fitch, M., Graham, C., (2000) Electricity and Gas Theft, , Centre for Utility Consumer Law, University of Leicester, UKKenny, C., Soreide, T., (2008) Grand Corruption in Utilities, , World Bank Policy Research Working Paper 4805Sarpa, C., (2008) Electricity Theft and Non-payment: Impact on the sa Generation Capacity Crisis, , Yelland, Conference PaperOnat, N., Techno-economic analysis of illegal electricity usage in Turkey and policy proposals (2010) WSEAS Transactions on Power Systems, 3, pp. 213-222Stajic, Z., Janjic, A., Simendic, Z., Power quality and electrical energy losses as a key drivers for smart grid platform development (2011) Proceedings of the 15th WSEAS International Conference on Systems - Recent Researches in System Science, pp. 417-422Kadurek, P., Blom, J., Cobben, J., Kling, W., Theft detection and smart metering practices and expectations in the Netherlands (2010) Innovative Smart Grid Technologies Conference Europe (ISGT Europe) IEEE PESOliveira-De Jesus, P., Alvarez, M., De Ponce Leao, M., Yusta, J., A novel approach to evaluate incremental transmission losses (2009) WSEAS Transactions on Power Systems, 1, pp. 12-21Ghajar, R.F., Khalife, J., Cost/benefit analysis of an AMR system to reduce electricity theft and maximize revenues for Électricité du Liban (2003) Applied Energy, 76 (1-3), pp. 25-37. , DOI 10.1016/S0306-2619(03)00044-8Nagi, J., Mohammad, A., Yap, K., Tiong, S., Ahmed, S., Non-technical loss analysis for detection of electricity theft using support vector machines (2008) Proceedings of the 2nd IEEE International Conference on Power and Energy (PECon 08), pp. 907-912(2008) MSP430FE42x Mixed Signal Microcontroller Data-sheet, , Texas Instruments(2011) CC2550 Low-cost Low-power 2.4 GHz RF Transmitter Data-Sheet, , Texas InstrumentsMorais, F., (2011) Development of an Electronic Wireless RMS Current Meter for Applications in Detection of Electrical Energy Theft, , M. Sc. Thesis in Electrical Engineering, Faculty of Computer and Electrical Engineering, University of Campinas, BrazilPomilio, J., Deckmann, S., Characterization and compensation of harmonics and reactive power of residential and commercial loads (2007) IEEE Transactions on Power Delivery,

Orbital-selective Mott transitions: Heavy fermions and beyond

Quantum phase transitions in metals are often accompanied by violations of Fermi liquid behavior in the quantum critical regime. Particularly fascinating are transitions beyond the Landau-Ginzburg-Wilson concept of a local order parameter. The breakdown of the Kondo effect in heavy-fermion metals constitutes a prime example of such a transition. Here, the strongly correlated f electrons become localized and disappear from the Fermi surface, implying that the transition is equivalent to an orbital-selective Mott transition, as has been discussed for multi-band transition-metal oxides. In this article, available theoretical descriptions for orbital-selective Mott transitions will be reviewed, with an emphasis on conceptual aspects like the distinction between different low-temperature phases and the structure of the global phase diagram. Selected results for quantum critical properties will be listed as well. Finally, a brief overview is given on experiments which have been interpreted in terms of orbital-selective Mott physics.Comment: 29 pages, 4 figs, mini-review prepared for a special issue of JLT

An overview on the reactors to study drinking water biofilms

The development of biofilms in drinking water distribution systems (DWDS) can cause pipe degradation, changes in the water organoleptic properties but the main problem is related to the public health. Biofilms are the main responsible for the microbial presence in drinking water (DW) and can be reservoirs for pathogens. Therefore, the understanding of the mechanisms underlying biofilm formation and behavior is of utmost importance in order to create effective control strategies. As the study of biofilms in real DWDS is difficult, several devices have been developed. These devices allow biofilm formation under controlled conditions of physical (flow velocity, shear stress, temperature, type of pipe material, etc), chemical (type and amount of nutrients, type of disinfectant and residuals, organic and inorganic particles, ions, etc) and biological (composition of microbial community e type of microorganism and characteristics) parameters, ensuring that the operational conditions are similar as possible to the DWDS conditions in order to achieve results that can be applied to the real scenarios. The devices used in DW biofilm studies can be divided essentially in two groups, those usually applied in situ and the bench top laboratorial reactors. The selection of a device should be obviously in accordance with the aim of the study and its advantages and limitations should be evaluated to obtain reproducible results that can be transposed into the reality of the DWDS. The aim of this review is to provide an overview on the main reactors used in DW biofilm studies, describing their characteristics and applications, taking into account their main advantages and limitations.This work was supported by the Operational Programme for Competitiveness Factors COMPETE and by Portuguese Foundation for Science and Technology through Project Phyto disinfectants - PTDC/DTPSAP/1078/2012 (COMPETE: FCOMP-01-0124-FEDER-028765), the Post-Doc grant awarded to Lucia Simoes (SFRH/BPD/81982/2011). Also, this work was undertaken as part of the European Research Project SUS-CLEAN (Contract n_FP7-KBBE-2011-5, project number: 287514) and the COST Action FA1202. The authors are solely responsible for this work. It does not represent the opinion of the Community, and the Community is not responsible for any use that might be made of data appearing herein