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RBI, referring to a risk-based approach to inspection planning, is an established pipeline integrity management method. Both corrosion and dents are the primary threats to pipeline integrity. However, they are often treated separately in RBI without considering their interactions. This coupling may lead to a synergic effect on integrity degradation. The present study proposes an RBI planning framework for pipelines considering external corrosion and dents. Time-dependent pipeline deterioration by dents and corrosion is modeled probabilistically using a Dynamic Bayesian Network (DBN), in-line inspection (ILI) data, and corrosion propagation knowledge. Two failure scenarios (leakage and burst) are considered. The hybrid method, integrating Monte Carlo Simulation (MCS) and Latin Hypercube Sampling (LHS) technique, estimates the pipeline's Probability of Failure (PoF) over time. The pipeline failure risk is quantified by monetizing the Consequence of Failure (CoF). An optimization model of loss-maintenance total expected cost is introduced to determine the optimum inspection period using maximum acceptable risk (MAR) and the lowest total expected cost. A cost-benefit analysis (CBA) is finally implemented to choose appropriate risk reduction measures. The proposed framework is robust and well-validated by a case study on an in-service pipeline. [ABSTRACT FROM AUTHOR]

The aircraft maintenance, repair and overhaul (MRO) industry is gradually switching to 3D scanning for dent inspection. High-accuracy devices allow for quick and repeatable measurements, which translate into efficient reporting and more objective damage evaluations. However, the potential of 3D scanners is far from being exploited. This is due to the traditional way in which the structural repair manual (SRM) deals with dents, that is, considering length, width and depth as the only relevant measures. Being equivalent to describing a dent similarly to a 'box', the current approach discards any information about the actual shape. This leads to a high degree of ambiguity, with very different shapes (and corresponding fatigue life) being classified as the same, and nullifies the effort of acquiring such a great amount of information from high-accuracy 3D scanners. In this paper, a seven-parameter model is proposed to describe the actual dent shape, thus enabling the exploitation of the high-fidelity data produced by 3D scanners. The compact set of values can then be compared against historical data and structural evaluations based on the same model. The proposed approach has been evaluated in both simulations and point cloud data generated by 8tree's dentCHECK tool, suggesting an increased capability in the evaluation of damage, enabling more targeted interventions and, ultimately, saving costs. [ABSTRACT FROM AUTHOR]

Securing an endotracheal tube (ETT) in a patient with facial burns poses many challenges. There is no standard practice and the existing literature provides solutions to this problem with limited detail outlining the specifics of their techniques. The teeth offer a rigid point of fixation and are an adaptable method to secure the ETT. For their dental insight, oral and maxillofacial surgeons are often tasked with the procedure of fixing the ETT to the dentition. The aim of this technical note is to review the previously published methods of securing an ETT in burns patients and to present a logical technique to secure the ETT to the dentition for critical care clinicians without dental experience. [ABSTRACT FROM AUTHOR]

There is worldwide interest in transporting hydrogen using both new pipelines and pipelines converted from natural gas service. Laboratory tests investigating the effect of hydrogen on the mechanical properties of pipeline steels have shown that even low partial pressures of hydrogen can substantially reduce properties such as reduction in area and fracture toughness, and increase fatigue crack growth rates. However, qualitative arguments suggest that the effects on pipelines may not be as severe as predicted from the small scale tests. If the trends seen in laboratory tests do occur in service, there are implications for the assessment of damage such as volumetric corrosion, dents and mechanical interference. Most pipeline damage assessment methods are semi-empirical and have been calibrated with data from full scale tests that did not involve hydrogen. Hence the European Pipeline Research Group (EPRG) commissioned a study to investigate damage assessment methods in the presence of hydrogen. Two example pipeline designs were considered, both were assessed assuming a modern, high performance material and an older material. From these analyses, the numerical results show that the high toughness material will tolerate damage even if the properties are degraded by hydrogen exposure. However, low toughness materials may not be able to tolerate some types of severe damage. If the predictions are realistic, operators may have to repair more damage or reduce operating pressures. Furthermore, damage involving cracking may not satisfy the ASME B31.12 requirements for preventing time dependent crack growth. Further work is required to determine if the effects predicted using small scale laboratory test data will occur in practice.

The weaving reed is considered to be one of the most important weaving loom components, also it has a huge effect on the appearance properties of the produced fabrics, as a lot of functions are applied by the weaving reed, one of the most important is to bush the last weft to the previous weaved ones during the sly moving forward using the reed dents to form the fabric.That is why the reed dents are very important as it represent the pressing point during the sly moving forward to the last thrown weft, and its effect on the straightness of the weft yarns all over the fabric.In this research these dents function was considered, as those dents have been changed along the reed, by using and applying some of the decorative weaving reeds with the different arranging and density for the dents, we find that using those reeds affected the decorations on the fabric surface, these decorations is a lines in the warp direction, these weaving reeds added value to the produced fabric using it, we didn't need to only use the weaving structure, yarns color or drawing in to achieve a nice simply doctorate fabrics.It is to be noted too that using these reeds have an obvious effect on some of the fabrics mechanical properties air permeability is one of the most properties which have effect on the produced fabrics.the reeds with more narrow spacing is more air permeable than that of the fabric produced with more wide spacing reed and reeds with irregular spacing .also the research results shows that the fabrics produced with cotton is more air permeable than that produced using the acrylic material.Key wards Weaving reed – dents - mechanical properties – decorative

To explore the effect of dents on the tribological behavior of the "washers-cage-rollers" system of rolling element bearings (REBs), the friction and wear properties of dents textured thrust cylindrical roller bearings (81107TN) with different diameters of dents (DAOD, 200, 250, 300 μm), depth of dents (DPOD, 4, 8, 12 μm) as well as circumferential interval angle (CFIA, 1.5°, 2.0°, 2.5°) were researched under dry wear. The surface stresses of REBs and the influence mechanism of dents were also compared and discussed. The results show that: due to the nylon film formed and left on the raceways, the coefficients of friction (COFs) of dents textured bearings are all higher than the average COF of smooth ones, while their wear losses may become higher or lower, depending on the combination of pattern parameters. The influence of the DPOD on the tribological performance of textured bearings is more significant than that of the DAOD. The results show that, when the DAOD and DPOD are 250 and 8 μm, respectively, compared with the smooth ones, the mass losses of bearings can be reduced by up to 49.22% under dry wear, which would be an important reference for the optimal design of the "washers-cage-rollers" system of REBs. [ABSTRACT FROM AUTHOR]

Many simulations employed in microwave heating simplify the geometric model of the microwave cavity to reduce the complexity of the model. Some detailed design features of the cavity, such as magnetron and cavity depression, are usually ignored. This study built detailed geometric models (DGM) and simplified geometric models (SGM) to investigate the changes in the electric field in a microwave cavity. A three-dimensional finite element model was developed to simulate rotating and stationary food (mashed potatoes) during microwave heating, and the simulation parameters and strategy during rotation were optimized. The simulations using DGM and SGM were compared by comparing the simulated transient temperature profiles and spatial temperature patterns with physical experiments. The results indicate that the temperature patterns of the DGM differed significantly from the SGM, and the simulation results of the DGM were closer to the experimental results. The presence of the magnetron, plastic bearing and detailed glass turntable had little influence on the electric field, but the dents had the great influence. The influence of dents on the heating uniformity was discussed in detail. [ABSTRACT FROM AUTHOR]

Mechanical damage in form of dents, cracks, gouges, and scratches are common in pipelines. Sometimes, these damages form in proximity of each other and act as one defect in the pipe wall. The combined defects have been found to be more injurious than individual defects. One of the combined defects in pipeline comprises of a crack in a dent, also known as dent-crack defect. This paper discusses the development of finite element models using extended finite element criterion (XFEM) in Abaqus to predict burst pressure of specimens of API X70 pipeline with restrained and unrestrained concentric dent-crack defects. The models are calibrated and validated using results of full-scale burst tests. The effects of crack length, crack depth, dent depth, and denting pressure on burst pressure are investigated. The results show that restrained dent-crack defects with shallow cracks (depth less than 50% wall thickness) inside dents do not affect pipeline operations at maximum allowable operating pressure if crack lengths are less than 200 mm. Releasing restrained dent-cracks when the pressure is at maximum allowable operating pressure can cause propagation of deep cracks (depth of 50% wall thickness or more) longer than 60 mm. However, only very long cracks (200 mm and higher) propagate to burst the pipe. Cracks of depth less than 20% of wall thickness inside dents formed at zero pressure are not propagated by the maximum allowable operating pressure. Dent-crack defects having dents of depth less than 2% outside diameter of pipe behave as plain cracks if the dents are formed at zero denting pressure but are more injurious than plain cracks if the dents are formed in pressurized pipes. [ABSTRACT FROM AUTHOR]

• Analytical method developed and verified to model impact events on metal plates. • Transition region introduced between local deformation and global deflection. • Deductive process defined for predicting the impactor from damage dimensions. • Model result error was lowest for plates with thickness range of 1.5–3 mm. • Analytical method is faster and accurate (<10% error) compared to FEM. This paper proposes an analytical model that uses historical damage dimension data to deduce physical impactor characteristics (size and energy) that has caused a certain resulting damage. Maintenance tasks occur in operations due to impact, however the source of the damage caused in the event remains in most cases unknown. Consequently, by inferring what has caused a certain type of damage from the distribution of the damage type and severity relative to impactor types, maintainers can be better prepared in terms of what to expect from a given impactor source. The developed model introduces a novel transition deformation region between the local deformation and the global plate deflection, allowing for fast and accurate predictions of the impact event. Using the known aluminium structural properties and damage dimensions, the damage data is converted into impactor data. The model is applied in a case study using 120 fuselage dent damages dimensions (length, width, and depth) from a Boeing 777 fleet. The results show that the model deduces impactor characteristics for 94% of the considered damages, ranging up to 240 J and 110 mm for impactor energy and radius respectively. [ABSTRACT FROM AUTHOR]

This paper presents the results of fatigue tests performed on dented steel pipeline specimens that were tested under different environmental conditions and subjected to cyclic internal pressure. Thirty-three pipe specimens were divided into three groups and tested under three different conditions. A first set of nine dented specimens was tested in air without any restrictions. A second set of eight specimens was tested while buried in the soil. A third set of sixteen specimens was tested in air, after the dents had been repaired by composite material sleeves. Hot-spot cyclic strain amplitudes were measured using two experimental techniques: Digital Image Correlation (DIC) and Fiber Optic Bragg Strain Gauges (FBSG). At first, all thirty-three specimens were tested in air along five full cycles in order to carry out full-field measurements using DIC to identify and quantify strain concentration at sites that were potential locations for fatigue cracks to initiate. Close to these point-locations, measurements of strains using FBSG were also made, and the results were then compared with the DIC results. FBSG were also used during the cyclic pressure loading process while the specimens were being tested, in such a way as to monitor the influence of the environment in the dented areas. The test results demonstrated that a simple uniaxial Manson-Coffin fatigue equation that uses the universal exponents proposed by Manson, together with the circumferential strain amplitude measured at the hot spots can be used to predict the fatigue life of the dented specimens. Moreover, it was determined that the measured strains at the hot-spot locations were not influenced by the soil coverage, although showing a considerable and beneficial decrease in their amplitudes caused by the composite repair reinforcements.

In this article we consider the increase of the resource of wheelsets of cars and locomotives. We give general data on present research in the field of tribotechnical systems, and offer alternative variants of development of domestic tribotechnical systems for railway transportation, which can be useful to replace foreign systems. The systems capable of increasing the reliability of a railway branch are described.

Wood products are perceived as premium products. Therefore, visible surface defects are undesirable. The current defect detection in wood products is by manual visual inspection. There is scant research data available on the defects plaguing the downstream wood industry. This paper determined the extent of such defects in assembled wooden veneered interior doors produced in a Malaysian manufacturing plant, focusing on American red oak (Quercus spp.), yellow poplar (Liriodendron tulipifera) and maple (Acer spp.) species. Industrial random sampling defect data was classified into seven defect categories. Pareto analysis showed that handling defects----particularly scratches/dents and knife marks----were the most prevalent, constituting 30% of all defects. The relationship between human ocular physiology and defect detection ability was tested using SPARCS (Spaeth/Richman Contrast Sensitivity) methodology, which was found to be a good lowcontrast ability predictor. Several common errors causing false positives were also identified. Comparisons using statistical t-tests between industry personnel and non-experts, and between genders showed that there was no difference in detection performance. In conclusion, human fallibility was the main cause of failure in detecting defects, particularly those with low contrast. Human behavioural results gathered in this study can be utilised as benchmarks for future automation studies. [ABSTRACT FROM AUTHOR]

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Thin-walled cylindrical shells are commonly used in numerous branches of industry. Since they are subjected to axial load, the most common cause of their failure is buckling. This paper provides numerical analysis and experimental verification of the buckling of the thin-walled aluminium alloy cylindrical shell with special regard to the influence of dent, positioned in the middle of the shell. Numerical simulation was performed using ANSYS 16.2, and experimental verification was performed by means of hydraulic press Armavir, PSU-50, which was used to subject the specimen to the increasing axial load until the occurrence of buckling. Comparing the results it was concluded that there is significant decrease of the buckling resistance if compared the values of the specimen with no dent, and the specimen with 2 mm deep dent. On the contrary, resistance of the 2 mm and 4 mm dented specimen is quite similar. Position and shape of the deformations occurred due to buckling are matching if experimental and numerical results are compared.

Mechanical damage in form of dents, cracks, gouges, and scratches are common in pipelines. Sometimes, these damages form in proximity of each other and act as one defect in the pipe wall. The combined defects have been found to be more injurious than individual defects. One of the combined defects in pipeline comprises of a crack in a dent, also known as dent-crack defect. This paper discusses the development of finite element models using extended finite element criterion (XFEM) in Abaqus to predict burst pressure of specimens of API X70 pipeline with restrained and unrestrained concentric dent-crack defects. The models are calibrated and validated using results of full-scale burst tests. The effects of crack length, crack depth, dent depth, and denting pressure on burst pressure are investigated. The results show that restrained dent-crack defects with shallow cracks (depth less than 50% wall thickness) inside dents do not affect pipeline operations at maximum allowable operating pressure if crack lengths are less than 200 mm. Releasing restrained dent-cracks when the pressure is at maximum allowable operating pressure can cause propagation of deep cracks (depth of 50% wall thickness or more) longer than 60 mm. However, only very long cracks (200 mm and higher) propagate to burst the pipe. Cracks of depth less than 20% of wall thickness inside dents formed at zero pressure are not propagated by the maximum allowable operating pressure. Dent-crack defects having dents of depth less than 2% outside diameter of pipe behave as plain cracks if the dents are formed at zero denting pressure but are more injurious than plain cracks if the dents are formed in pressurized pipes.

Objective: To examine the effect of a nutrition and hygiene education intervention on oral health behaviour and whether early onset of caries was related to child growth in rural Uganda.Methods: Follow-up study of a cluster-randomised controlled trial conducted between October 2013 and January 2015. Data were available from 399 mother/child pairs (203 in the intervention and 198 in the control group) of the original trial (78%) when the children were 36 months old. Oral health behaviour was evaluated using questionnaires. Photographs of the maxillary anterior teeth were examined for unmistakably carious lesions, and 115 water samples from the study area were analysed for fluoride concentration.Results: The frequency of cleaning of the child's teeth at 36 months was about twice as high in the intervention as in the control group (84.3% vs. 46.6%; P = 0.0001). Cavitated carious lesions occurred more frequently in the control than the intervention group (27.8% vs. 18.2%; P = 0.04). Extraction of 'false teeth' (ebiino), a painful and crude traditional operation, was profoundly reduced in the intervention group (8.9% vs. 24.7%; P = 0.001). There was no evidence of association between the occurrence of caries and child growth.Conclusions: The education intervention improved oral hygiene practices and reduced the development and progression of caries and extraction of ebiino. Early childhood caries was not clearly associated with child growth. [ABSTRACT FROM AUTHOR]

In this work, chaotic dynamics of flexible spherical axially symmetric shallow shells subjected to sinusoidal transverse load is studied with emphasis put on the vibration modes. Chaos reliability is verified and validated by solving the implemented mathematical model by partial nonlinear equations governing the dynamics of flexible spherical shells and by estimating the signs of the largest Lyapunov exponents with the help of qualitatively different approaches. It is shown how the scenario of transition of the investigated shells from regular to chaotic vibrations depends on the boundary condition. The following cases are considered: (1) movable and fixed simple supports along the shell contours, taking into account shell stiffness (Feigenbaum scenario) and shell damping (Ruelle–Takens–Newhouse scenario), and (2) movable clamping (regular shell vibrations). The presence of dents, the location and character of which essentially depend on the shell geometric parameters, boundary conditions, and the external load parameters, is detected in some regions of the shell surface and discussed. [ABSTRACT FROM AUTHOR]

This study aims to present a preliminary approach to the suitability of the “source and sink” model to explain the human settlement of East Asia. We present a general overview of the hominin dental evidence with a special emphasis in some key localities with human remains that have been recently described. Our analysis suggests that the morpho-dimensional variation of the Pleistocene populations from East Asia cannot be accommodated within one single lineage. This evidence seems supportive of an intense but also more discontinuous pattern of occupation. The severe climatic oscillations, the extent of the desert areas and the possibility of intermittent exchanges between continental and insular East Asia, depending on sea level changes, are key factors to identify possible sink and sources in the region. Future studies should focus in a large-scale characterization of the Asian hominins in order to identify morphologically coherent groups and to understand the evolutionary story behind their spatio-temporal distribution. [ABSTRACT FROM AUTHOR]

Dents are commonly localized defects in ball bearings (BABEs), which are also the primary cause of material surface level fatigue failure for the BABEs. A new dynamic model for BABEs with a dent on its race is proposed to investigate the effect of the dent on vibrations of the BABE in this work. The proposed model can consider the effect of the shoulder of the dent on vibrations of a BABE, which cannot be described by the previous dent models without considering the effect of the shoulder in the literature. The time-varying contact force caused by the dent with the shoulder is formulated in the proposed model. Based on the simulation and experimental results in the previous works, the profiles of the dent and its shoulder are considered as a sinusoidal and an exponential function shapes, respectively. The simulation results from the proposed model and previous dent model in the literature are compared. Effects of sizes of the dent on the vibrations of the BABE are discussed. The results show that a dent with the shoulder on the races of a BABE can significantly affect vibration characteristics of the bearing. It seems that the proposed method can provide a new method for dynamic formulation of a BABE considering a dent with the shoulder. Moreover, this study gives a more close to real impulse characteristics caused by a practical dent compared to the previous dent models without the shoulder. [ABSTRACT FROM AUTHOR]

In this study, we investigate outer and inner variations of upper second molars (UM2) for Late Pleistocene and Early Holocene modern humans, at a key-period in our evolutionary history associated with major sociocultural, economic and environmental changes. Non-metric traits have been recorded on 89 UM2 of 66 Upper Paleolithic, Mesolithic and Neolithic individuals, and 40 UM2 have been microscanned to assess variations in enamel thickness (ET) distribution and enamel–dentine junction (EDJ) shape. Major changes are found between Mesolithic and Neolithic periods: a decrease of the metacone expression combined with an increase of the hypocone development; an increase of the heterogeneity of ET distribution between lingual and buccal cusps; and an increase of the development of the dentine horn tips corresponding to the hypocone and, to a lesser extent, to the metacone. These morphological modifications could be linked to the masticatory functional changes associated with the transition to agriculture. [ABSTRACT FROM AUTHOR]

This paper presents a characterisation of surface damage, more specifically dents, caused by low velocity impacts of blunt objects on RR1000 Nickel superalloys. These are representative of damage that may occur during handling and service of components during manufacturing or maintenance. The characterisation of dents produced in laboratory tests is carried out both in terms of their geometry and the residual stresses the damage. A finite element model is presented and the results are validated in terms of dent geometry produced for different impact velocities. The stress distribution predicted by the numerical model is also compared with experimentally measured stresses via X-ray diffraction for validation of the model. The residual stresses obtained from the finite element (FE) model and their implications to fatigue and crack propagation lives are also discussed here. [ABSTRACT FROM AUTHOR]

In this article we consider the increase of the resource of wheelsets of cars and locomotives. We give general data on present research in the field of tribotechnical systems, and offer alternative variants of development of domestic tribotechnical systems for railway transportation, which can be useful to replace foreign systems. The systems capable of increasing the reliability of a railway branch are described. [ABSTRACT FROM AUTHOR]

The present study aims at characterizing the variability of the Late Pleistocene to Holocene western Indonesian archipelago ancient populations based on second molars , which are described by means of comparative morphology (ASUDAS), and metrics (BL and MD measurements). We furthermore test similarity and differentiation by metric and non-metric statistics analysis to observe group clustering among the samples. Results show two different dental types. The "Preneolithic" one is present on Early to Middle Holocene fossils, between 12 to 4.5 ka, and the "Neolithic-Paleometallic" type consists of Late Holocene remains, from 3.2 ka. This study opens new perspectives regarding the scenario of human occupation in the western Indonesian archipelago during those periods, and questions as well the chronological significance of some features classically described as 'archaic' or 'derived' in dental palaeoanthropology. [ABSTRACT FROM AUTHOR]

The relevance of research. Oil production is one of the most important industries in the Russian economy at present time. It depends to a large extent on the level of applied geophysical information and measurement systems on the basis of physical methods of obtaining information. The acoustic method is one of the leading methods of borehole geophysics. The amounts of using this method are about 10 % of all volume of well logging. The relevance of the study is caused by the need to improve the accuracy of the data obtained using acoustic logging. The effectiveness of the acoustic logging depends on the quality of the package of elastic waves. It is detected by the acoustic logging devices. The development of a mathematical model of the element motion in flexible spherical converter and study of the frequency characteristics of elastic vibrations are very important scientific and practical problems. The aim of the research is to study the forced vibrations of a spherical transducer, which is a part of the acoustic logging. Results. The authors have constructed the initial differential equations of motion of an axisymmetric spherical shell element using the variational principles and taking into account the geometric nonlinearity in the form of the Kirchhoff-Love and developed the algorithm for solving the systems of nonlinear differential equations using the finite difference method, the matrix and Runge-Kutta methods. Nonlinear vibrations of a spherical shell were analyzed based on non-linear dynamics and the qualitative theory of differential equations. It is shown that the dents in the vicinity of certain surface lines are possible in problems of nonlinear dynamics of axisymmetric spherical shells It was found that the transition from harmonic vibrations to chaotic ones occurs according to the scenario of Ruelle-Takens-Newhouse for rigidly clamped spherical shell (excitation frequency is close to the natural frequency of the shell).

La estimación de la edad de los caballos basado en el examen de los dientes es una labor poco aplicada y limitada por los Médicos Veterinarios, quizás por desconocimiento de los parámetros establecidos en la cronología dentaria equina. Sin embargo, es la forma más adecuada de conocer o verificar la edad de los caballos, aunque tengan o no registros establecidos. En el presente trabajo, se hace una revisión de aspectos relevantes en la dentadura de los equinos, con el fin de conocer y determinar la edad de los ejemplares examinados. Se describe, en forma detallada la estructura del diente, los tipos de dientes, la formula dentaria de los caballos y su evolución en el tiempo, con base en los eventos encontrados.Estimation of horse age based on the teeth exam is a work seldom applied and limited by the Medical Veterinaries, due perhaps to ignorance of the established parameters in the equine dental chronology. However, it is the best-suited form to know or to verify the horse’s age, although they have or not established records. In the present work a revision of relevant aspects in the denture of the specimens in order to know and to establish the horses age is made. A detailed description of the tooth structure is realized, as well as of the dental formula and its evolution in time.

Objective To study the relationship between the mental health status and health risk behaviors among nursing students of secondary vocational school. Methods A total of 1 650 nursing students in the grade 2013 and 2014 of a secondary vocational school were performed the investigation by using the stratified cluster random sampling method. Results The total positive detection rate of mental problems in nursing students of secondary vocational school was 32.5% (537/1 650); the mental health status of urban students was better than that of rural students, which of the grade 2013 students was superior to the grade 2014 students；the proportion of the students with health risk behavior occurrence was higher than that of the students without mental problems. Unhealthy dietary,lack of high intensity exercise,smoking,suicidal idea and internet addiction tendency were the risk factors for mental problem occurrence. Conclusion The mental health status has a relation with health risk behaviors. Many health risk behaviors are the risk factors of mental problems. The related departments should strengthen the mental health education in nursing students of secondary vocational school, actively carry out the intervention activities of health risk behaviors for promoting the physical and mental healthy development in nursing students or secondary vocational school. [ABSTRACT FROM AUTHOR]

The Oligocene locality at Aubenas-les-Alpes, France, has yielded an interesting sample of anthracotheres representing two subfamilies, Anthracotheriinae and Bothriodontinae. The large dental remains are attributed to Anthracotherium magnum , the smaller dental and postcranial fossils are attributed to Elomeryx crispus . The phalanges of the latter species are proximo-distally shortened, suggesting a brachypothere-like distal limb morphology, in contrast to the elongated pedal elements that are usually found in anthracotheres. The presence of these two taxa at the site agrees with correlation to MP 25. [ABSTRACT FROM AUTHOR]

This work presents an assessment of the ultimate compressive strength of damaged steel plates with a local dent. Extensive non-linear finite element analyses are performed, where three groups of analyses are considered. In the first group, the effect of the dent orientation (longitudinal and transverse) is studied for three plate thicknesses. For the second group, the direction of the dent depth (upward and downward) with respect to the global initial imperfection is explored. In the third group, the variation of the dent size for several plate thicknesses and its influence on ultimate compressive strength is investigated. The post-collapse behaviours are discussed and the inflection plate slenderness with and without dent is observed, at which the behaviour of the plate changed. A certain dent breadth to the plate breadth ratio is established, revealing the different plate response. Based on the performed analyses, a generalised expression of the ultimate strength reduction factor due to dent is developed. [ABSTRACT FROM PUBLISHER]

We studied crown morphology of Martes foina , M. martes , and M. zibellina from different regions of the northern Eurasia and described its morphotypes. The following has been identified: three morphotypes for P3, eight morphotypes for P4, 16 morphotypes for M1, four morphotypes for i3, three morphotypes for p3, four morphotypes for p4, nine morphotypes for m1, and three morphotypes for m2. Morphotypes for P4, i3, m1, and m2 are described for the first time. Morphotype frequency is given for each species. It was found that 3 teeth (i3, m1, and m2) are enough for differentiation of the sable, stone marten, and pine marten. We used the above-mentioned dental patterns for species identification of the teeth belonging to the representatives of the genus Martes from archaeological sites of the southern Urals. M. foina , M. martes , and M. zibellina inhabited the territory under study in the Holocene. We have also given some consideration to the morphotypes of Tertiary and Quaternary members of the genus Martes and come to preliminary conclusions about evolutionary trends. [ABSTRACT FROM AUTHOR]

En este documento se presentan las pruebas experimentales, y sus resultados, realizadas durante el diseño y desarrollo de un Material Compuesto Orgánico (MCO) para refuerzo y recubrimiento de tuberías de transporte de fluidos. El MCO se diseña para ser utilizado en oleoductos que presenten daños superficiales externos tipo abolladuras o picado por corrosión. El MCO puede recuperar líneas de transporte con defectos del 65% de pérdida de espesor por corrosión en longitudes no mayores a 0,2 m (es posible reforzar defectos de mayor profundidad, pero en menores longitudes). El sistema desarrollado por Ecopetrol-ICP, tiene la particularidad de detener el avance de la corrosión, posee excelente capilaridad, buena adhesión, buena resistencia en protección catódica y buena resistencia mecánica, suficiente para la presión de operación de un oleoducto. El MCO consiste en una matriz polimérica (resinas epóxicas) reforzada con fibras orgánicas. Una ventaja que da a este producto una alta competitividad es su bajo peso, muy apropiado para ciertas aplicaciones donde éste es un factor problema. Finalmente, el sistema puede ser aplicado tanto en tuberías enterradas como sobre superficie, sin necesidad de suspender la operación. La presión de ruptura máxima alcanzada por el MCO es de 23,4 MPa (instalado en tuberías con defectos de pérdida de espesor por corrosión del 65%), comparativamente la presión de operación normal de un oleoducto no supera los 1 0 ó 12 MPa.This paper presents the experimental test and the results of the development of a composite organic material (MCO) for the reinforcement and covering of pipelines. MCO is desinged to be applied to pipelines with external, damages such as dents or gauges or with surface damages caused by corrosion. The product can recover transport lines with 65% thickness losses due to corrosion in lenghts of less than 0,2 m. The system developed by Ecopetrol-ICP can stop progressive picking corrosion, it has an excellent capillary, good adhesion, good resistance in cathodic protection, and mechanical strength that can support the operational pressure of the pipeline. MCO is a mixture of a polymeric resin reinforced with organic fibers, it can be applied to surface or underground pipelines without stopping normal operation. The maximum rupture pressure attained by the MCO was 23,4 MPa in pipelines with a 65% tickness loss due to corrosion. The normal operation pressure is 1 0 - 1 2 MPa.

Se registra en este artículo la amplia experiencia obtenida en el oleoducto Caño Limón Coveñas, OCLC, Colombia, sobre el manejo y evaluación de las abolladuras causadas en la tubería por cargas explosivas. El OCLC ha sido sometido a más de 450 atentados terroristas con cargas explosivas. La mayoría de estos daños no llegan a la ruptura total de la tubería sino que generan deformaciones o abolladuras permanentes, mayores al 5%. Por lo tanto, se trata de adquirir elementos de juicio para la toma de decisiones sobre cuándo cambiarla y a su vez conocer el rango de presión en el cual puede operar el oleoducto de manera continua y segura. En el estudio se consideran varios aspectos relacionados con la evaluación de las abolladuras. Estos son: (a) La caracterización de las abolladuras en cuanto a la geometría, materiales (dureza, estructura metalográfica y esfuerzos, entre otros), efectos de las cargas explosivas y de la presión de operación y pruebas de presión hidrostática en tuberías a escala real, (b) La creación y validación de un nuevo procedimiento para evaluarlas abolladuras, (c) Discusión del análisis con modelamiento numérico. Los resultados muestran un aumento en la resistencia elástica y de ruptura del material localizada en la zona afectada y, por lo tanto, una disminución de la resistencia a la fatiga. Esta última es posiblemente la causa de la ruptura posterior de la tubería una vez ha sido abollada por la carga explosiva. Las pruebas hidrostáticas han demostrado que la tubería, al ser sometida a la presión interna de operación, sufre una recuperación parcial de su forma. En el caso de una abolladura tipo 24%, a presión de 1 2,4 MPa, se recuperará 0,036 m.This paper presents the broad experience obtained in the Caño Limón Coveñas pipeline (OCLC), located in Colombia, on the manipulation and evaluation of the dents caused by explosive charges. During the last ten years, the OCLC pipeline has suffered more than 450 terrorist attacks using explosive charges. Most of the damages do not cause the total rupture of the pipes, they only generate dents and distortions grater than five percent (5%). A as consequence of this situation, we have tried to acquire all the judgement elements required to choose the appropriate time to change the pipes an to know the pressure level for a continuos and safe operation of the pipeline. The study include some three main aspects: (a) Characterization of the dents considering their geometry, materials (hardness, metallographic structure, efforts, etc) influences of explosive charges and of the operation pressure as well as hydrostatic pressure tests overa real scale pipe, (b) Creation and validation of a new method for dent evaluation and (c) Discussion of the analysis through numeric modeling. Results show an increase in the elastic and rupture resistance of the material located in the target area and therefore, a subsequuent fatigue resistance decrease. Fatigue is the possible cause for the subsequent rupture of the pipeline once it has been dented by an explosive charge. The hidrostatic tests have shown that a partial shape recovery is obtained when the pipeline undergoes a high operational pressure. For a 24% dent there will be 0.036 m recovery at a 1 2.4 Mpa pressure.

L’estudi ha estat realitzat sobre restes dentals recuperades al jaciment de Forat de Conqueta. La majoria de les dents s’han trobat aïllades, fora del suport ossi, la qual cosa n’ha dificultat la identificació i l’estudi. Entre els objectius de l’estudi paleodontològic, volem destacar la determinació d’un nombre mínim i màxim d’individus a partir de les restes. L’estudi ha estat molt limitat a causa de la tipologia funerària (enterrament col·lectiu en cova) i del ritual d’enterrament (cremació parcial). El resultats provisionals assenyalen que el nombre mínim d’individus representats per la mostra estudiada és de 41 i que, d’aquests, fins a sis individus podrien pertànyer a un grup d’edat infantil o juvenil.

Vikings with artificially modified teeth have previously been documented in the south-eastern parts of Scandinavia and in England. In a project dealing with life in the Mälaren Valley in Sweden during the period ad 750-1100, new cases of people with modified maxillary teeth were observed. The hypothesis that the practice was entirely associated with adult men dating to the Viking Age was tested. The new cases demonstrate that the habit extended to eastern-central Sweden, including the proto-town of Birka, perhaps as early as in the middle of the eighth century. Additionally, cases from Sigtuna show that the practice may have ended as late as the beginning of the twelfth century. A microanalysis, using a scanning electron microscope, showed the heterogeneous character of the modifications. The affected individuals were all adult men, similar to previously published cases. Some of the men are associated with weapons and violent acts and the cases from Sigtuna were all from cemeteries with a possible association with lower social strata. However, discrepancies in archaeological contexts and in the characteristics of the modifications suggest temporal and spatial variation in the social meaning of the modifications. [ABSTRACT FROM AUTHOR]

Abstract: The tooth types in the embryos of the hammerhead sharks Sphyrna tiburo, Sphyrna tudes and Eusphyra blochii are here described in labial and lingual views, and, in some cases, in additional views. The presence of cusplets was observed in the anterior teeth of S. tiburo and S. tudes, which is secondarily lost after early embryonic stages. Many aligned root foramina were detected in the sphyrnids, which, as the cusplets, are shared by many phylogenetic-related carcharhinids. Other anatomic features, related to the root and central cusp, are presented for the first time. Such characters represent the first step to compare the teeth of extant and fossil species. [Copyright &y& Elsevier]

Identification of the individuals represented in a fragmentary fossil assemblage is a key step in paleobiological research, as ensuing organism-level studies, as well as sampling strategies (e.g., DNA, isotopes, dating, etc.), may depend on the reliability of such estimates. In the human fossil record, dental remains represent the most abundant and informative material, allowing individual identification on the basis of a variety of diagnostic criteria. In this paper, we present a procedure for sequential association of the dental remains and the identification of the minimum number of individuals (MNI) represented in the 49,000-year-old Neandertal assemblage from El Sidrón (Asturias, Spain). In order to quantify the possible association errors, the 12 criteria used in this study are organised according to three levels of reliability. Following this procedure, a minimum of 13 individuals (seven adults, three adolescents, two juveniles and one infant) have been identified at El Sidrón, two of them uniquely represented by postcranial elements. A next step in this investigation foresees the development of methods for associating postcranial elements with the dentally-based identified individuals. [ABSTRACT FROM AUTHOR]

Résumé: Les restes néandertaliens découverts dans la Caverna delle Fate à Finale Ligure (Italie) comprennent une majorité de matériel dentaire : dix dents isolées et six dents sur arcade ou incluses dans une mandibule d’adulte Fate 3 et une mandibule d’un enfant de 8–10ans, Fate 2. Jusqu’à présent, c’est l’ensemble le plus important de dents néandertaliennes recueillies en Italie, accompagné de données archéostratigraphiques et paléoenvironnementales précises. Aucune dent déciduale perdue naturellement n’a été retrouvée. L’ensemble dentaire est bien conservé, peu altéré par l’usure. Les données morphométriques confirment la possibilité de l’existence d’une population néandertalienne gracile sur les bords de l’arc méditerranéen septentrional européen. Ces populations sont en place depuis le stade isotopique 5.1, c’est-à-dire entre 80 000 et 70 000ans. Cette gracilité doit être interprétée comme liée à une population locale et non à un stade évolutif. [ABSTRACT FROM AUTHOR]