The aim of this study was to assess the effect of blood contamination on the shear bond strength and failure site of three different orthodontic self-ligating brackets.
240 bovine permanent ...mandibular incisors were randomly divided into 12 groups of 20 specimens each. Orthodontic self-ligating brackets were tested under four different enamel surface conditions: a) dry, b) blood contamination before priming, c) blood contamination after priming, d) blood contamination before and after priming. Brackets were bonded to the teeth and subsequently tested using a Instron universal testing machine. Shear bond strength values and adhesive failure rate were recorded. Statistical analysis was performed using ANOVA and Tukey tests (strength values), and Chi squared test (ARI Scores).
Non-contaminated enamel surfaces showed highest bond strengths for all self ligating brackets. Under blood-contamination shear bond strengths lowered for all brackets tested. Groups contaminated before and after primer application showed the lowest shear bond strength. Significant differences in debond locations were found among the groups under the various enamel surface conditions.
Blood contamination of enamel during the bonding procedure lowers bond strength values of self ligating brackets, expecially when contamination occur in different times of the bonding procedure.
Spatial and temporal patterns in the bycatch of seabirds in the Argentinian longline fishery were investigated. Observers sampled 156 seats and hauls from December 2000 to September 2001. Observers ...recorded the date, number of hooks deployed, position and time of the start and end of each set, water depth, and sea condition. Bootstrapping method was used to calculate the 95% confidence limits for the mean number of birds caught/1000 hooks and made 10,000 simulations. Seabirds whose sex was determined were used to test differences from the 1:1 sex ratio. It was found that most fishing and bycatch occurred between 48-46 degree S latitude and 63-61 degree W longitude. The observed distribution of genders was not significantly different from an expected 1:1 sex ratio for albatrosses or petrels.
The purpose of this longitudinal prospective randomized study was to evaluate the clinical reliability of two different types of postorthodontic treatment retainers: a silanised-treated glass ...fibers-reinforced resin composite (FRC) and a directly bonded multistranded stainless steel wire. The hypothesis of the study was to assess if significant differences are present between failure rates of the two retainers.
This prospective study was based on an assessment of 87 patients (35 men and 52 women),with an average age of 24 years who required a lower arch fixed retainer after orthodontic treatment. Patients were divided in two groups. Assignment was carried out with random tables. A follow-up examination was carried out once a month. The number, cause, and date of single bond adhesive failures were recorded for both retainers over 12 months. Teeth that were rebonded after failure were not included in the success analysis. Statistical analysis was performed by means of a Fisher's exact test, Kaplan-Meier survival estimates, and log rank test.
Bond failure rate was significantly higher (P=0.0392) for multistranded metallic wire than for FRC.
Glass fiber-reinforced resin composite retainers and multistranded metallic wires showed no significant difference in single bond failure rates over a one-year follow up. Key words:Fiber reinforced composite, fixed retention, multistranded wire, orthodontics, retainer, splint.
Male and female Kelp Gulls (Larus dominicanus) are not clearly sexually dimorphic and are thus difficult to identify in the field. This paper evaluates sexual size dimorphism in this species and ...provides a reliable method for predicting the sex of measured individuals. Discriminant analysis of six morphometric characters of adult birds indicated that head length, bill length and bill depth were the most accurate variables for use in a discriminant function model, predicting sex with 97% accuracy.
DESTINATION project, started in 2010 in the framework of the Italy/Switzerland Operational Program for Transfrontier Co-operation 2007-2013, was born to answer to the increasing needs of public ...bodies to share data on hazardous material land transportation and to develop instruments and methodologies to ensure territorial and environmental protection. The partnership is made of 5 members: Canton Ticino, Piedmont Region as Leader of the project, Lombardy Region, Autonomous Region of Aosta Valley and Autonomous Province of Bolzano Alto Adige. Technical partners working on DESTINATION are CSI Piemonte, 5T S.r.l. and Laboratorio Mobilità e Trasporti del Politecnico di Milano. One of the main objective of the project is the definition of a risk analysis model of the land transportation of hazardous materials, able to take into account even environmental vulnerabilities. It will constitute the basis to a new information system design called GIIS (Global Integrated Information System), in order to contribute to road accident prevention, real-time monitoring of Dangerous Goods Transportation by road (DGT) through On Board Units and fixed points (gates) and more efficient emergency management. In this paper we describe the DGT risk model designed and the main features of the Information System that is going to be developed.
This study explores the possibility that the celiac disease (CD) may be correlated with the insurgence of some oral signs, as based on a systematic review of the literature. Should this correlation ...be proven, any dentistry's screening would then be important to diagnose early celiac sprue pathogenesis. A literature survey was accomplished by using the Medline database (Entrez PubMed). The survey, which covered the period from the year 1972 to 2009, provided 382 published articles. Of these, 29 articles were selected according to inclusionary/exclusionary criteria, and consequently qualified for the final review analysis. Manual searching through the reference lists of the selected articles allowed the obtainment of others 17 articles. Findings gathered through this literature's review corroborate the significance of a causal relationship between some oral signs and CD. There are enough evidence making the correlation between CD and oral defects scientifically sustainable. This recognition should lead dentists to play more significant roles in screening for CD, as otherwise, if not properly diagnosed and not treated with a gluten-free diet, may eventually cause some malignancies.
The foraging behavior and feeding locations of the Red-legged Cormorant (Phalacrocorax gaimardi) were studied at Ria Deseado, Argentina during the last week of the incubation period in 1999. VHF ...radio-transmitters were deployed on six nesting adult cormorants. Red-legged Cormorants fed during the daylight hours and made 4.0 ± 0.8 trips per day, with a mean duration of 1.2 ± 0.8 h. Birds spent 27% of daylight hours away from the colony on feeding trips, diving for 96% of the foraging trip, and made a mean of 78 dives per trip. Mean foraging range was 1.9 ± 0.9 km, being the shortest of any of the Patagonian cormorant species. Red-legged Cormorants fed mainly in shallow waters <5 m deep and within one km from the shore. Most of the feeding trips were undertaken during falling tide, when the birds performed the shortest feeding trips with maximum diving rates and, probably minimized transit times and maximized searching time on the seafloor. Our results show that foraging behavior is mainly influenced by environmental factors such as the direction of the tide. Red-legged Cormorants seems able to forage by selecting the appropriated tidal conditions to minimize foraging effort.
The diet of Black-browed Albatross Thalassarche melanophrys has been studied at several sub-Antarctic colonies (e.g. Ridoux 1994, Reid et al. 1996, Xavier et al. 2003) and found to consist mainly of ...fish, cephalopods and crustaceans. Although this albatross species travels vast distances during the non-breeding season (Croxall & Wood 2002), the types of food taken remain similar, although prey species and percentages tend to vary (Xavier et al. 2003, Gandini et al. unpubl.). Nevertheless, other prey items--such as seabirds, chiefly Spheniscidae and Pelecanoididae (Cherel & Klages 1997) and terns Sterna spp. (Colabuono et al. 2006)--have been occasionally taken by albatrosses. Here we report, for the first time, the finding of remains of a Wilson's Storm-Petrel Oceanites oceanicus in the stomach contents of a Black-browed Albatross.
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