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Copyright of Archives of Cardiovascular Diseases is the property of Elsevier B.V. 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.)

A complete cranium of Ursus deningeri from Petralona (Chalkidiki, Greece) covered by a thick carbonate crust has been virtually liberated through CT scan and 3D image reconstruction, and compared with a specimen from the Sima de los Huesos, Sierra de Atapuerca (Spain) Middle Pleistocene site. X-ray computed tomography allowed for the identification of previously unrecognized and phylogenetically relevant traits. Analysis of these traits and an additional series of classically defined traits demonstrate the near identity of these specimens, thereby, confirming an early stage of the speloid “(cave bear)” condition. The replicate luminescence ages obtained for the SH deposit provide a combined minimum age estimate of 427 ± 12 ka for the underlying fossils. Based on a series of primitive and derived morphological features of these two crania, a similar age is here proposed for the Petralona and SH U. deningeri . [ABSTRACT FROM AUTHOR]

Abstract: This paper presents flow imaging techniques developed for investigating flow in ejectors. These visualization techniques use the laser sheet method but differ from each other by the kind of the illumination source, the polarization direction of the incident light and the type of the scattering tracers. Each of these methods enables the visualization of specific phenomena (shock structure, flow instabilities, mixing process). Although the flow visualizations are primarily qualitative, they allow the determination of the flow regime, the measurement of the non-mixing length, can indicate suggestions for the design of ejectors and provide the possibility to validate numerical simulations. [Copyright &y& Elsevier]

Copyright of Zeitschrift für Medizinische Physik is the property of Elsevier GmbH, Urban & Fischer Verlag 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.)

Abstract: Objective: A cancer diagnostics method is proposed using the 3D reconstruction of luminescence-based optical imaging data. Material and methods: The diffusion equation solution for a cube was used to tackle the forward problem. The forward solution for two-layered media is also applied in the reconstruction method. The inverse problem was solved using a linear reconstruction technique based on the approximation that the light source needing reconstruction can be decomposed into a weighted sum of unit light sources positioned at each node in the search volume. The calculation for the light propagation in the forward problem was done using values cited in literature for the optical properties of the involved tissue. Results: The system was tested with numerical simulations that assumed correct as well as erroneous values of the optical coefficients for canine prostate at 810nm. The quantitative accuracy of reconstructed sources diminished from 100% to approximately 50% with an increase from 0 to 50% in the error for the values of the absorption coefficient, and from 0 to 20% in the error for the values of the reduced scattering coefficient, respectively. Conclusion: The absolute determination of the tumor locations is dependent on the information gathered by the recorded data by the detectors monitoring the light propagation through the tissue under investigation. For a determined or an over-determined system, the locations have been extracted accurately, and partially determined for an under-determined system. [ABSTRACT FROM AUTHOR]

Abstract: Due to the numerous discoveries of fossils and the technical and analytical improvements in paleoanthropology that occurred recently, a new investigation on the first inhabitants in Eurasia was necessary. The research deals with the facial pattern of the fossil hominids from Europe and Asia and focussed on the ones discovered in the Atapuerca-Gran Dolina site in Spain, which are oldest than 850,000 years and in the Yunxian site in China, which are dated by 936,000 years. Methods used combined 2D and 3D morphometrics providing with the possibility to consider not only the overall conformation but also the more localized measurements. The Procrustes analysis, which put apart the individual size parameter, were used to investigate the morphological alteration of the face during growth in order to interpret the facial conformation juvenile fossils such as those from Atapuerca-Gran Dolina. Moreover, a specific protocol using tomography and 3D imaging techniques was carried out to reconstruct the Yunxian specimens which have been badly crushed during fossilization process. The results of this research put in light two facial patterns: (1) a facial pattern in extension expressed in Neandertals which european lineage could have been older than previously thought including the Atapuerca-Gran Dolina specimens and (2) a facial pattern in contraction shared between modern humans and the oldest fossil hominids from continental Asia (i.e. Yunxian specimens) which suggests that this conformation corresponds to a primitive condition. [Copyright &y& Elsevier]

Abstract: The most deadly of the human malaria parasites, Plasmodium falciparum, invades the erythrocytes of its host and initiates a remarkable series of morphological rearrangements within the host cell cytoplasm. The mature erythrocyte is effectively a floating sack of haemoglobin with no endogenous protein synthesis or protein trafficking machinery. In order to colonise and remodel its extracellular space, the parasite generates a series of novel structures that are involved in the export of virulence factors to the surface of the host cell. These include extensions of the parasite''s vacuolar membrane, known as the tubulovesicular network, and structures referred to as Maurer''s clefts. Maurer''s clefts are convoluted collections of distorted discs that are tethered to the red blood cell membrane by structures with stalk-like profiles. Recently electron tomography has enabled visualisation – in three dimensions and at unprecedented resolution – the complexity of the membrane systems within the infected RBC cytoplasm. [Copyright &y& Elsevier]