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2012, Evolutionary Anthropology
https://doi.org/10.1002/EVAN.21325…
4 pages
1 file
American Journal of Human Biology, 2009
The Anatomical Record, 2015
Interest in the lateralization of the human brain is evident through a multidisciplinary number of scientific studies. Understanding volumetric brain asymmetries allows the distinction between normal development stages and behavior, as well as brain diseases. We aimed to evaluate volumetric asymmetries in order to select the best gyri able to classify rightversus left cerebral hemispheres. A cross-sectional study performed in 47 right-handed young-adults healthy volunteers. SPM-based software performed brain segmentation, automatic labeling and volumetric analyses for 54 regions involving the cerebral lobes, basal ganglia and cerebellum from each cerebral hemisphere. Multivariate discriminant analysis (DA) allowed the assembling of a predictive model. DA revealed one discriminant function that significantly differentiated left vs. right cerebral hemispheres: Wilks' k 5 0.008, v 2 (9) 5 238.837, P < 0.001. The model explained 99.20% of the variation in the grouping variable and depicted an overall predictive accuracy of 98.8%. With the influence of gender; the selected gyri able to discriminate between hemispheres were middle orbital frontal gyrus (g.), angular g., supramarginal g., middle cingulum g., inferior orbital frontal g., calcarine g., inferior parietal lobule and the pars triangularis inferior frontal g. Specific brain gyri are able to accurately classify left vs. right cerebral hemispheres by using a multivariate approach; the selected regions correspond to key brain areas involved in attention, internal thought, vision and language; our findings favored the concept
Anatomical record (Hoboken, N.J. : 2007), 2015
The African Plio-Pleistocene hominins known as australopiths evolved derived craniodental features frequently interpreted as adaptations for feeding on either hard, or compliant/tough foods. Among australopiths, Paranthropus boisei is the most robust form, exhibiting traits traditionally hypothesized to produce high bite forces efficiently and strengthen the face against feeding stresses. However, recent mechanical analyses imply that P. boisei may not have been an efficient producer of bite force and that robust morphology in primates is not necessarily strong. Here we use an engineering method, finite element analysis, to show that the facial skeleton of P. boisei is structurally strong, exhibits a strain pattern different from that in chimpanzees (Pan troglodytes) and Australopithecus africanus, and efficiently produces high bite force. It has been suggested that P. boisei consumed a diet of compliant/tough foods like grass blades and sedge pith. However, the blunt occlusal topog...
Complexity, 2010
The proposition that complexity generally increases with evolution seems indisputable. Both developmental and generational changes often display a rise in the number and diversity of properties describing a wide spectrum of ordered systems, whether physical, biological, or cultural. This article explores a quantitative metric that can help to explain the emergence and evolution of galaxies, stars, planets, and life throughout the history of the Universe. Energy rate density is a single, measurable, and unambiguous quantity uniformly characterizing Nature's many varied complex systems, potentially dictating their natural selection on vast spatial and temporal scales.
Anatomical Record-advances in Integrative Anatomy and Evolutionary Biology, 2009
Occipital growth depends on coordinated deposition and resorption on the external and internal surface and includes interrelated processes of movement: cortical drift, displacement, and relocation. The current work aspires to map patterns of remodeling activity on the endocranial surface of the occipital bone from childhood to adulthood using a larger study sample compared with previous studies. The study sample consists of 5 adult and 10 immature (2¼ to 8 years old) occipital bones from skeletal remains from the eighteenth and nineteenth century. Preparation of the samples includes the elaboration of negative impressions, positive replicas coated with gold, and observed with the reflected light microscope. Cerebellar fossae are typically resorptive in both immature and adult specimens. Cerebral fossae, on the other hand, exhibit a resorptive surface in early childhood and turn into depository around the age of 7 years, which places this transition within the age interval of the completion of cerebral development. Depository fields are also observed in adult cerebral fossae. The remodeling map presented here is consistent with the results of Mowbray (Anat Rec B New Anat 2005;283B:14–22) and differs from cellular patterns described by Enlow. Future research implicating more elements of the neurocapsule can shed light on the factors affecting and driving occipital growth. Anat Rec, 2009. © 2009 Wiley-Liss, Inc.
Anatomical Sciences Education, 2011
"It is argued in this article that the human body both in health and disease cannot be fully understood without adequately accounting for the different levels of human variation.The article focuses on variation due to ancestry, arguing that the inclusion of information pertaining to ancestry in human anatomy teaching materials and courses should be carried out and implemented with care and in line with latest developments in biological anthropology and related sciences. This seems to be of particular importance in the education of health professionals, as recent research suggests that better knowledge of human variation can improve clinical skills. It is also argued that relatively small curricular changes relating to the teaching of human variation can produce significant educational gains."
Research article in JGR, 2014
In this study, we used more than 17 years of satellite altimetry observations and output from 9 an ocean model to investigate the mesoscale eddy variability and forcing mechanisms to the south of 10 Madagascar. Analysis of energy conversion terms in the model has shown seasonality on eddy formation, 11 both by barotropic and baroclinic instabilities: maximum in winter (JJA) and minimum in summer (DJF). The 12 eddies were mainly formed in the upper ocean (0-300 m) and at intermediate depths (800-2000 m) by bar-13 otropic and baroclinic instabilities, respectively. The former dominated in the southeastern margin of Mada-14 gascar, and the latter to the southwest, where the South-East Madagascar Current (SEMC) separates from 15 the continental shelf. Seasonality of the eddy formation appeared linked with the seasonal intensification of 16 the SEMC. The energy conversion terms indicated that the eddies have a significant contribution to the 17 large-scale circulation, but not being persistent throughout the year, occurring mainly during the fall season 18 (MAM). Eddy demography from altimetry and model provided information on eddy preferential sites for 19 birth, annual occurrence (6-13 per year), eddy mean diameter (124-178 km), mean amplitude (9-28 cm), 20 life-time (90-183 days), and maximum traveling distances (325-1052 km). Eddies formed to the southwest 21 of Madagascar exhibited distinct characteristics from those formed in the southeast. Nevertheless, all eddies 22 were highly nonlinear, suggesting that they are potential vectors of connectivity between Madagascar and 23 Africa. This may have a significant impact on the ecology of this region. 24 25 26 2006; Palastanga et al., 2007]. It is located offshore of the SEMC, and transports 10 Sv in the upper 800 m 42 depth [Siedler et al., 2006] above SEC, along the 25 S latitude band [Palastanga et al., 2007].
BioFactors, 2013
Cancer immunosurvelliance usually leads to formation of cancer cells that have been "immunoedited" to resist anti-tumor immunity. One of the consequences of immunoediting that is, reduced immunogenicity, is an important roadblock in revival of stable and long-lasting anti-tumor immune responses. Research done during the last decade has shown that emission by the dying cancer cells of immunomodulatory factors or damage-associated molecular patterns (DAMPs), which can act as danger signals, is a critical event in accentuating the immunogenicity of cancer cells, in response to a subset of anticancer treatments. Recent evidence has defined that an apoptotic cell death subroutine and its underlying biochemistry, which has been termed as "immunogenic cell death (ICD)" or "immunogenic apoptosis," is required for the efficient emission of DAMPs and inciting anti-tumor immunity. Here, we review the basic concepts of ICD, like cancer immunogenicity, danger signals, and DAMPs. Moreover, we discuss the emerging molecular links between endoplasmic reticulum (ER) stress, induction of a viral response-like gene expression, danger signals, and anti-tumor immunity. We envisage that along with ER stress-based trafficking of DAMPs (which is a "short-range communicator" of danger), the accompanying induction of a viral response-like gene expression and the secretion of anti-tumorigenic cytokines (acting as "long-range communicator" of danger) may become a crucial signature of ICD induction by anticancer therapy. V C 2013 International
Seasonal vegetation changes during the North American monsoon play a major role in modifying water, energy and momentum fluxes. Nevertheless, most models parameterize plants as a static component or with averaged seasonal variations that ignore interannual differences and their potential impact on evapotranspiration (ET) and its components. Here, vegetation parameters derived from remote sensing data were coupled with a hydrologic model at two eddy covariance (EC) sites with observations spanning multiple summers. Sinaloan thornscrub (ST) and Madrean woodland (MW) sites, arranged at intermediate and high elevations along mountain fronts in northwest Mexico, occupy specific niches related to climate conditions and water availability that are poorly understood. We found that simulations with a dynamic representation of vegetation greening tracked well the seasonal evolution of observed ET and soil moisture (SM). A switch in the dominant component of ET from soil evaporation (E) to plant transpiration (T) was observed for each ecosystem depending on the timing and magnitude of vegetation greening that is directly tied to rainfall characteristics. Differences in vegetation greening at the ST and MW sites lead to a dominance of transpiration at ST (T/ET = 57%), but evaporation-dominant conditions at MW (T/ET = 19%). Peak transpiration occurred at five and twenty days after the full canopy development in the ST and MW sites, respectively. These results indicate that evapotranspiration timing and partitioning varies considerably in the two studied ecosystems in accordance with different modes of vegetation greening. Intermediate-elevation ecosystems follow an intensive water use strategy with a rapid and robust transpiration response to water availability. In contrast, higher elevation sites have delayed and attenuated transpiration, suggesting an extensive water use strategy persisting beyond the North American monsoon.
The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology, 2010
The formation of both germline cysts and the germinal epithelium is described during the ovary development in Cyprinus carpio. As in the undifferentiated gonad of mammals, cords of PGCs become oogonia when they are surrounded by somatic cells. Ovarian differentiation is triggered when oogonia proliferate and enter meiosis, becoming oocytes. Proliferation of single oogonium results in clusters of interconnected oocytes, the germline cysts, that are encompassed by somatic prefollicle cells and form cell nests. Both PGCs and cell nests are delimited by a basement membrane. Ovarian follicles originate from the germline cysts, about the time of meiotic arrest, as prefollicle cells surround oocytes, individualizing them. They synthesize a basement membrane and an oocyte forms a follicle. With the formation of the stroma, unspecialized mesenchymal cells differentiate, and encompass each follicle, forming the theca. The follicle, basement membrane, and theca constitute the follicle complex. Along the ventral region of the differentiating ovary, the epithelium invaginates to form the ovigerous lamellae whose developing surface epithelium, the germinal epithelium, is composed of epithelial cells, germline cysts with oogonia, oocytes, and developing follicles. The germinal epithelium rests upon a basement membrane. The follicles complexes are connected to the germinal epithelium by a shared portion of basement membrane. In the differentiated ovary, germ cell proliferation in the epithelium forms nests in which there are the germline cysts. Germline cysts, groups of cells that form from a single founder cell and are joined by intercellular bridges, are conserved throughout the vertebrates, as is the germinal epithelium. Anat Rec, 00:000-000,