230 research outputs found

    A semi-automated method for daily age estimation in larval populations by discriminant function models

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    Discriminant analysis including the best age-correlated variables selected by SMLR’s to construct a predictive model based on somatic and otolith biometry was applied. Age of anchovy larvae ranging from 10 to 12 mm collected along Western Mediterranean coasts during MEDIAS209 survey were estimated by otolith microstructure analysis and compared with the number of daily increments estimated by the model. The model compound by Perimeter2 + Area2 was able to estimate correctly the age of the otoliths in 75% of the cases assuming ±1 day of error increasing to 90% assuming ±2 days of error with mean values of APE (3.33%) and CV (4.71%) systematically low. The results indicate the precision of the increment estimates. Moreover, no differences between the estimated ages from direct readings and those estimated by the model were observed. The proposed method implies a reduction in the subjectivity factor and the cost/benefit ratio for ageing studies in fish larvae.Postprint1,586

    Third canal in the mesial root of permanent mandibular first molars : review of the literature and presentation of 3 clinical reports and 2 in vitro studies

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    Introduction. Systematic anatomical studies corroborate the anatomical complexity of the root canal system. Deviations from the norm such as multiple orifices, apical deltas, accessory canals and other variations are frequent. Objectives. To present clinical reports of mandibular molars with three canals in the mesial root and two in vitro studies of the morphology of these canals, together with a review of the literature. Materials and Methods. Three clinical reports are presented of mandibular molars where three canals in the mesial roots were treated endodontically. Two in vitro studies were performed, one using computerized tomography and the other with scanning electron microscopy, to describe the morphology of the mesial root canals of permanent first molars. The scientific literature on this anatomical situation was also reviewed. Results. The tomographic study found that the prevalence of a third mesial canal in the 27 teeth analysed was 14.81%; the microscopic study of 25 teeth found it to be 12%. The review of the literature encountered that the authors who report cases such as these found prevalences ranging from 1% to 15%. Conclusions. From the teeth analysed in vitro, it is concluded that a third mesial canal may be present in a mandibular first molar in approximately 13% of cases. Clinically, the third canal is difficult to find and exhibits a very variable morphology, which may present anastomosis with the other canals

    Plasticidad del crecimiento larvario entre atĂşn rojo y melva modulado por sus interacciones trĂłficas.

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    ECOlogía trófica comparativa de LArvas de aTUN rojo atlántico (Thunnus thynnus) de las áreas de puesta del Medterraneo-NO y el Golfo de México.ECOLATU

    Evaluation of morphological changes produced by orifice opener systems using computerized tomography (CT)

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    Objectives: To evaluate modifications in root canal morphology following instrumentation with orifice openers using Computerized Tomography (CT). Study design: Experimental in vitro study. A preoperative CT was performed on 49 molars to measure the root canal cross-sections. After preparing the canals with 6 different nickel-titanium (Ni-Ti) rotary system orifice opener type instruments and Gates Glidden burs, a further CT was made and compared with the preoperative one. Kruskal-Wallis and ANOVA statistical analysis were used. Results: Gates Glidden burs were significantly more aggressive in the coronal portion of the canals, although all the instruments removed more dental tissue in the most coronal of the sections studied. Bucco-lingual diameters were modified more than the mesio-distal ones. The stainless steel instruments used lead to greater modifications being required in the canals than those made of nickel-titanium. The ProFile system instruments were observed to be those that caused the least amount of change. Conclusions: Stainless steel burs are more aggressive than new orifice openers without significant differences observed between Ni-Ti instrument

    Cutting efficiency evaluation of Quantec Series 2000 orifice openers with computed tomography (CT)

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    Introduction: Orifice openers or orifice shapers are used to shape the coronal part of the root canals during endodontic treatment. Objectives: The aim of this work was to analyse the cutting efficiency of Quantec Series 2000 system orifice shapers by means of computerised tomography (CT). Materials and methods: Mandibular molars were selected, preoperative CT was performed and the cross-sections and surface area of the root canals were measured. Following access opening and preparation of the coronal part of the canals with Quantec Series 2000 orifice shapers, a further CT was obtained of all the teeth, the previous measurements were repeated and the two sets of measurements were compared. Results: Although the canals suffered modifications due to the action of the instruments, they remained centred and retained their original morphology; the changes were greater in the most coronal part of the canals. Conclusions: the orifice shapers of the system under study kept the canals centred on their original position, so they do not present great aggressiveness during endodontic treatment; the canals that were initially the widest were those that showed the greatest modification; the CT system employed in the study showed itself to be an effective, noninvasive system for studying the changes that had taken place inside the root canals

    Climate-induced environmental conditions influencing interannual variability of Mediterranean bluefin (Thunnus thynnus) larval growth

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    Daily growth variability of bluefin (Thunnus thynnus) larvae sampled in their Balearic Sea spawning grounds during the 2003–2005 spawning seasons was examined. Multi-factorial ANOVA was applied to study the effects of environmental variables, such as temperature at 10 m depth (T10), microzooplankton dry weight (MDW) and protein/dry weight ratio (PROT/ MDW) on larval growth. The 2003 bluefin tuna (BFT) larval cohort showed the fastest growth, recognizable from enhanced otolith and somatic mass increment compared to the 2004–2005 larval cohorts. The 2003 BFT larvae showed greater recent growth than the 2004–2005 BFT cohorts, which decreased in the last stages of development. Growth differences between the 2004 and 2005 larval cohorts were not significant. The environmental conditions between 2003 and 2004–2005 were highly contrasting as a result of the 2003 warming anomaly. Somatic and otolith growth rates (OGR) were significantly related to T10 and MDW, as well as to the PROT/MDW ratios. Nonetheless, the effect of T10 on OGR depended on the relative high (H) or low (L) levels of MDW and PROT/DW. Higher OGR was observed when T10 was high, MDW was low and PROT/DW was high. This environmental scenario conditions were met during 2003, which recorded the highest surface temperature and low planktonic biomass. Somatic growth,expressed as larval DW growth increase (DWGR), showed three-factor significant interactions with T10*MDW*PROT/MDW, in which the two-way interactions of MDW*PROT/MDW showed differences in the function of T10 levels.Postprin

    Epidemiology of injuries in professional and amateur spanish paddle players

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    Se realizó un estudio epidemiológico descriptivo, observacional y retrospectivo, analizando la incidencia y las características de las lesiones sufridas por jugadores de pádel españoles profesionales y no profesionales. Se registraron las lesiones sufridas por 478 jugadores entre el 1 de enero y el 31 de diciembre de 2016. Se registraron datos sobre el número de lesiones, lesiones más frecuentes, distribución, tipo, ubicación, el momento en que ocurrieron y la causa de las lesiones que afectan el sistema locomotor. La tasa de lesiones en esta población fue de 2,75 lesiones por 1000 horas de exposición al riesgo. Las lesiones leves y aquellas con mecanismos de lesión intrínseca fueron las más frecuentes, y tuvieron lugar el final de la práctica deportiva. La extremidad inferior fue el área corporal más lesionada, y el tejido más lesionado fue el sistema musculo-tendinoso. A su vez, la epicondilitis fue la patología más comúnAn epidemiological study was conducted using retrospective, observational and descriptive methodologies. We sought to analyse the incidence and features of injuries sustained by professional and non-professional Spanish Padel players. In total, 478 injuries were registered in 2016 from January 1st to December 31st. We collected data on the number of injuries, the most frequent injuries, their distribution, type, location, the moment at which these occurred and the cause of the injuries affecting the locomotor system. We found that the injury rate in this population was 2.75 injuries per 1000 hours of risk exposure. The most frequent injuries were those which were mild or with mechanisms of intrinsic injury, and most occurred towards the end any given game or practice. The lower limb was the most frequently injured body area, and the most injured tissue was the muscle-tendinous system. In turn, epicondylitis was the most common patholog

    Composite resins : A review of the materials and clinical indications

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    The aim of this work is to present the different components of the composites currently used in dentistry and furnish dentists with a basis that can provide criteria for choosing one or another to suit their therapeutic requirements. Most composites used in dentistry are hybrid materials, so-called because they are composed of polymer groups reinforced by an inorganic phase of glass fillers with different compositions, particle sizes and fill percentages. Flowable or condensable composites have attempted to provide an answer to certain functional requirements, although they have not been too successful at improving properties. Turning to polymerisation initiators, both halogen lamps, whether conventional or high intensity, and LED curing lights which provide a gradual increase in light intensity are very useful for reducing shrinkage of the composite material. The clinical choice of a composite must consider whether priority should be given to mechanical or aesthetic requirements: if mechanical considerations are paramount the material with the greatest volume of filler will be chosen; if aesthetic considerations predominate, particle size will be the most important factor. Additional components such as opaques and tints make it possible to improve the aesthetic results. Equally, the spread of other therapeutic procedures, such as tooth bleaching, has made it necessary to design composite materials in shades that are suitable for the special colour situations found in teeth treated by these methods

    gh/igf axis gene expression profile in developing atlantic bluefin tuna (Thunnus thynnus).

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    Atlantic bluefin tuna (ABFT), Thunnus thynnus (Linnaeus, 1758), is a large migratory oceanic top predator, considered as an important worldwide fishery source and a key species in pelagic ecosystems. Survival during the early life stages is crucial for future recruitment success, with larval growth being a determining process. Fish growth and development are mainly controlled by the GH/IGF axis, being involved in skeletal and soft tissue growth, as well as in immune function, appetite control, behavior (including foraging, aggression, and predator avoidance). To characterize the ontogenetic development profile of the GH/IGF axis at the level of gene expression, an ABFT larval rearing experiment (under controlled feeding conditions) was performed in the aquaculture facilities of the Spanish Institute of Oceanography (IEO), in MazarrĂłn during June 2019. Eggs and larvae from 3 replicates were collected regularly every 2-3 days from 0 until 30 days post-hatching (dph). In a total of 14 sampling points (n = 6-12 larvae) along the ontogeny, growth hormone (gh) and two forms of insulin growth factor (igf1 and igf2) were analyzed by real-time RT-PCR. A sigmoidal gh expression profile was observed, with higher values at 5 and 23 (maximum) dph, and lower values at 0 (minimum), 12 and 30 dph. Nevertheless, igf1 and igf2 showed a gradual increase from early days, also with lower values at 0 and 12 dph, but with maximum levels at 30 dph. Results are discussed considering growing rates and transition from larvae to juvenile, underlining the importance of gh/ igf axis during the ABFT early development and growth
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