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Copyright of Biomédica: Revista del Instituto Nacional de Salud is the property of Instituto Nacional de Salud of Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Extant sea turtles develop and lay pliable (flexible) eggs; however, it is unknown whether they inherited this reproductive strategy from their closer fossil relatives or if it represents an evolutionary novelty. Here, we describe the first undisputable gravid marine fossil turtle ever found, from the early Cretaceous of Colombia, belonging to Desmatochelys padillai Cadena & Parham, which constitutes a representative of the Protostegidae. Using thin sectioning of one of the eggs, as well as scanning electron microscopy coupled with elemental characterization, cathodoluminescence, and computer tomography, we established that Desmatochelys padillai produced rigid eggs similar to those associated with some extant and fossil freshwater and terrestrial turtles. At least 48 spherical eggs were preserved inside this gravid turtle. We suggest that the development of rigid eggs in the extinct marine turtle Desmatochelys padillai resulted as an adaptation for egg‐embryo requirements dictated by the physical attributes of the nesting site. [ABSTRACT FROM AUTHOR]

Background: A growing link between prenatal exposure to misoprostol (PEM) and Moebius syndrome (MS) or sequence has been reported. Our objectives were to describe the craniofacial clinical manifestations associated with MS and to determine the frequency of PEM, comparing cases of exposure and nonexposure. Methods: A descriptive, cross‐sectional study of 140 patients with MS. Clinical evaluations, as well as 140 interviews with mothers residing in 39 cities or districts of Colombia, were carried out between April 2008 and May 2018. Additionally, previous clinical history of each case was reviewed. Results: The average age of the patients with MS was 8.4 years (29 days to 48 years). All of them presented facial nerve involvement and abducens, 112 (80.8%) with bilateral facial paralysis. 98.5% presented craniofacial disorders, and there were no significant differences between those exposed and not exposed to misoprostol. Forty‐seven percentage of patients (64 cases) presented PEM, in 98.4% of which abortion had been intended. Conclusion: PEM could have an influence in the appearance of new cases of MS by increasing the frequency of bleeding during gestation, without increasing the number of associated craniofacial malformations. We present the biggest series on MS and craniofacial findings in the literature, along with a meaningful reference for its understanding. Level of Evidence: 3b. [ABSTRACT FROM AUTHOR]

Copyright of Revista Educación en Ingeniería is the property of Asociacion Colombiana de Facultades de Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Facultad de Odontología Universidad de Antioquia is the property of Universidad de Antioquia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The bottom-simulating reflector (BSR) recognized in seismic sections represents the division between free gas and gas hydrate. This reflector has been identified in the permafrost and several petroliferous marine basins worldwide, including the Colombia offshore basins. Using high quality three-dimensional (3D) seismic data from the Sinú offshore basin (southern Caribbean), the BSR was exceptionally well-imaged within two geomorphological settings, including the Southern Caribbean Deformed Belt and the Colombia Basin, indicating possible gas hydrate presence in the study area. The BSR occurrence was mapped and categorized following existing nomenclature developed off Taiwan into three (3) categories: Basin-type, Ridge-type and Submarine Canyon-type. The BSR occurrence was dominated by the Ridge type category that was mainly found in the accretionary prism within modern and ancient anticlinal structures, followed by the Basin-type BSR found mainly at the Colombia Basin margin and a few intraslope sub-basins. The Submarine Canyon-type was found on small segments of the main drainage routes that cut through anticlinal structures. BSR distribution and characterization was also correlated with a seabed geomorphologic map, including thrusts with bathymetric expression, revealing that the BSR typology map closely resembled the N–S trend of subsurface structures in the south, as well as their NE-SW trend in the central portion of the accretionary prism. We suggest the dimensions (width and depth) of the seafloor features does influence BSR occurrence, tending to parallel major anticlines, and wider/deeper portions of intraslope sub-basins and submarine canyons, while omitting small-scale features. • New and high-quality seismic data from offshore Colombia. • Comprehensive mapping and classification of gas hydrate-related bottom simulating reflector (BSR). • Data are interpreted and combined with topographic and seafloor-morphological data to describe different types of BSR occurrences. • BSR typologies were biased to record larger convex-upward seafloor features such as modern and ancient anticlines. [ABSTRACT FROM AUTHOR]

This paper introduces the design, construction, and static testing of a solid rocket motor. The design was based on the solid rocket motor design methodology (SRM). The rocket motor included the igniter system, the combustion chamber, the solid propellant, and the nozzle. The internal diameter of the combustion chamber and the total length of the rocket motor were 27,67 mm and 230 mm, respectively. The rocket motor nozzle was of the convergent-divergent Laval type. The propellant was based on the mixture of potassium nitrate (KNO3) (oxidant) and high purity sugar (or sucrose: C12H22O11) (fuel), whose synthesis was achieved through a thermal fusion process (150-170 °C for 20-25 min). The performance of the rocket motor was evaluated using a static combustion test; resulting in a maximum thrust force (load) of 227 N, a total impulse of 98,69 Ns and a specific impulse of 65,8 s, thus allowing its classification as a class G rocket motor. The results obtained are considered of great importance in the development and characterization of solid rocket motors, necessary to promote the experimental rocketry in Colombia. [ABSTRACT FROM AUTHOR]

Platypterygius sachicarum is one of the few Lower Cretaceous ichthyosaurian species described from the Hauterivian–Aptian-aged Paja Formation, the most complete Lower Cretaceous sedimentary sequence in northern South America. To date, P. sachicarum has been described only from a single skull, limiting morphological, stratigraphic, and phylogenetic comparisons. Here, we describe a new skull and associated postcranium of upper Barremian age from Villa de Leyva, Colombia, which represent the first documented postcranial remains of this species and enable detailed comparison with other Early Cretaceous ophthalmosaurid ichthyosaurs. Platypterygius sachicarum shares many morphological similarities with contemporaneous taxa from Europe but differs in both skull and tooth morphology from coeval South American species from northern South America and from the eastern Pacific. The additional data provide new diagnostic characters for this species and resolve the position of P. sachicarum as part of a polytomy of other species historically referred to Platypterygius. However, as with previous analyses, all recovered clades are poorly supported. The rich vertebrate fossil record of the Paja Formation provides an unparalleled opportunity to explore paleobiogeographic and paleoecological questions pertaining to Cretaceous marine reptiles; however, in most cases, a robust stratigraphic and phylogenetic framework remains elusive. [ABSTRACT FROM AUTHOR]

Brachiosaurid sauropods achieved a broad distribution during the Late Jurassic, which has been considered to provide evidence of their origins during the Middle Jurassic, prior to the breakup of Pangea. In contrast to their broad geographic distribution during the Late Jurassic, formally named brachiosaurid species from the Cretaceous have so far been restricted to the Aptian–Albian of North America, which has been interpreted as a signal of differential extinction and/or a bias in the Early Cretaceous fossil record. Here we describe a new brachiosaurid titanosauriform taxon from the Early Cretaceous of Colombia, which is represented by axial elements. The material was recovered from marine sediments of the Paja Formation (Barremian), close to the locality of Villa de Leiva. The weakly laterally expanded and divided transverse processes of the anterior-most caudal vertebrae allows the recognition of a new sauropod taxon,Padillasaurus leivaensis, gen. et sp. nov. In order to test the phylogenetic relationships of the new taxon, we performed a cladistic analysis that recoveredPadillasaurusas a brachiosaurid titanosauriform. This position is supported by a combination of characters, including the presence of blind fossae in anterior caudal vertebrae. Among titanosauriforms, the presence of blind fossae in anterior caudal vertebrae is an apomorphic character that is exclusive toGiraffatitan, Venenosaurus, Cedarosaurus, andAbydosaurus. Although more complete remains are needed to test more thoroughly the affinities of the new taxon, the available evidence indicates that brachiosaurids survived at lower latitudes in Gondwana until at least the Early Cretaceous. http://zoobank.org/urn:lsid:zoobank.org:pub:652D6B2A-7A8A-4311-8725-279BF2C9E0E3 SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP [ABSTRACT FROM PUBLISHER]