989 research outputs found

    A new identification of the monkeys depicted in a Bronze Age wall painting from Akrotiri, Thera

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    Bronze Age Aegean (ca. 3500–1100 B.C.) wall paintings from the islands of Crete and Thera depict monkeys in a variety of roles such as running wild in nature, possibly following (trained) commands, and participating in sacred activities. These images, while stylistically Aegean, are traditionally considered closely related to—and descendant from—Egyptian, Near Eastern, and Mesopotamian monkey imagery. While monkey depictions in the latter regions may provide species-specific characteristics, Aegean wall paintings typically lack this level of detail. In an attempt to better understand the relationships between the monkeys depicted in Aegean wall paintings and the species that were encountered by the Aegean, Mesopotamian, and Egyptian peoples, a collaborative team of primatologists, a taxonomic illustrator, and an art historian/archaeologist identified species-indicative visual characteristics. This collaborative approach led us to identify a new region that serves as a source for monkey iconography: the Indus River Valley. With an emphasis on the primatological aspect and the growing corpus of possible Indus goods and possible species found in the Aegean, a broader iconographic and socioreligious sphere of interaction emerges. In this expanded system, Mesopotamia functions as an intermediary that enables the movement of goods, raw materials, people, and iconography between the east and west. Mesopotamia may have even afforded an opportunity for Aegean peoples to encounter the creatures themselves, first-hand. Of primary importance to the methodology employed for this project is the cooperation of scholars from disparate disciplines—the stitching together of various projects and experiences in attempt to answer both new and previously unanswerable questions. This type of interdisciplinary approach can be applied to other species, sites, paintings, and objects to hone our understanding of period, place, animal, movement, and trade

    Surfing a genetic association interaction network to identify modulators of antibody response to smallpox vaccine

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    The variation in antibody response to vaccination likely involves small contributions of numerous genetic variants, such as single-nucleotide polymorphisms (SNPs), which interact in gene networks and pathways. To accumulate the bits of genetic information relevant to the phenotype that are distributed throughout the interaction network, we develop a network eigenvector centrality algorithm (SNPrank) that is sensitive to the weak main effects, gene–gene interactions and small higher-order interactions through hub effects. Analogous to Google PageRank, we interpret the algorithm as the simulation of a random SNP surfer (RSS) that accumulates bits of information in the network through a dynamic probabilistic Markov chain. The transition matrix for the RSS is based on a data-driven genetic association interaction network (GAIN), the nodes of which are SNPs weighted by the main-effect strength and edges weighted by the gene–gene interaction strength. We apply SNPrank to a GAIN analysis of a candidate-gene association study on human immune response to smallpox vaccine. SNPrank implicates a SNP in the retinoid X receptor α (RXRA) gene through a network interaction effect on antibody response. This vitamin A- and D-signaling mediator has been previously implicated in human immune responses, although it would be neglected in a standard analysis because its significance is unremarkable outside the context of its network centrality. This work suggests SNPrank to be a powerful method for identifying network effects in genetic association data and reveals a potential vitamin regulation network association with antibody response

    Foundations of Black Hole Accretion Disk Theory

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    This review covers the main aspects of black hole accretion disk theory. We begin with the view that one of the main goals of the theory is to better understand the nature of black holes themselves. In this light we discuss how accretion disks might reveal some of the unique signatures of strong gravity: the event horizon, the innermost stable circular orbit, and the ergosphere. We then review, from a first-principles perspective, the physical processes at play in accretion disks. This leads us to the four primary accretion disk models that we review: Polish doughnuts (thick disks), Shakura-Sunyaev (thin) disks, slim disks, and advection-dominated accretion flows (ADAFs). After presenting the models we discuss issues of stability, oscillations, and jets. Following our review of the analytic work, we take a parallel approach in reviewing numerical studies of black hole accretion disks. We finish with a few select applications that highlight particular astrophysical applications: measurements of black hole mass and spin, black hole vs. neutron star accretion disks, black hole accretion disk spectral states, and quasi-periodic oscillations (QPOs).Comment: 91 pages, 23 figures, final published version available at http://www.livingreviews.org/lrr-2013-

    Therapeutic efficacy of intra-articular delivery of encapsulated human mesenchymal stem cells on early stage osteoarthritis

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    Mesenchymal stem cells (MSCs) represent a great therapeutic promise in pre-clinical models of osteoarthritis (OA), but many questions remain as to their therapeutic mechanism of action: engraftment versus paracrine action. Encapsulation of human MSCs (hMSCs) in sodium alginate microspheres allowed for the paracrine signaling properties of these cells to be isolated and studied independently of direct cellular engraftment. The objective of the present study was to quantitatively assess the efficacy of encapsulated hMSCs as a disease-modifying therapeutic for OA, using a medial meniscal tear (MMT) rat model. It was hypothesized that encapsulated hMSCs would have a therapeutic effect, through paracrine-mediated action, on early OA development. Lewis rats underwent MMT surgery to induce OA. 1 d post-surgery, rats received intra-articular injections of encapsulated hMSCs or controls (i.e., saline, empty capsules, non-encapsulated hMSCs). Microstructural changes in the knee joint were quantified using equilibrium partitioning of a ionic contrast agent based micro-computed tomography (EPIC-μCT) at 3 weeks post-surgery, an established time point for early OA. Encapsulated hMSCs significantly attenuated MMT-induced increases in articular cartilage swelling and surface roughness and augmented cartilaginous and mineralized osteophyte volumes. Cellular encapsulation allowed to isolate the hMSC paracrine signaling effects and demonstrated that hMSCs could exert a chondroprotective therapeutic role on early stage OA through paracrine signaling alone. In addition to this chondroprotective role, encapsulated hMSCs augmented the compensatory increases in osteophyte formation. The latter should be taken into strong consideration as many clinical trials using MSCs for OA are currently ongoing

    An infectious aetiology for childhood brain tumours? Evidence from space–time clustering and seasonality analyses

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    To investigate whether infections or other environmental exposures may be involved in the aetiology of childhood central nervous system tumours, we have analysed for space–time clustering and seasonality using population-based data from the North West of England for the period 1954 to 1998. Knox tests for space–time interactions between cases were applied with fixed thresholds of close in space, <5 km, and close in time, <1 year apart. Addresses at birth and diagnosis were used. Tests were repeated replacing geographical distance with distance to the Nth nearest neighbour. N was chosen such that the mean distance was 5 km. Data were also examined by a second order procedure based on K-functions. Tests for heterogeneity and Edwards' test for sinusoidal variation were applied to examine changes of incidence with month of birth or diagnosis. There was strong evidence of space–time clustering, particularly involving cases of astrocytoma and ependymoma. Analyses of seasonal variation showed excesses of cases born in the late Autumn or Winter. Results are consistent with a role for infections in a proportion of cases from these diagnostic groups. Further studies are needed to identify putative infectious agents

    Memories of being injured and patients' care trajectory after physical trauma

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    <p>Abstract</p> <p>Background</p> <p>The purpose of this study was to acquire a deeper understanding of patients' memories of being injured and the trajectory of care before, during and after their Intensive Care Unit (ICU) stay.</p> <p>Methods</p> <p>Interviews were conducted with eighteen informants who after physical trauma had been cared for in the ICU. The interviews were analyzed by using a phenomenological hermeneutical method.</p> <p>Results</p> <p>The memories of injury during the trajectory of care are illustrated in a figure in which the injured informants have memories from five scenes; the scene of the accident, emergency unit, ICU, nursing ward and of coming home. Twelve subthemes were abstracted and four themes emerged; a surrealistic world, an injured body, care, and gratitude for life. After the accident, a "surrealistic world" appeared along with bad memories of being in a floating existence where plans had to be changed. This world was unfamiliar, sometimes including delusional and fragmentary memories from the ICU, and it was experienced as uncontrollable. They felt connected to an "injured body", experiencing bad memories from the ICU of being injured, from the nursing ward of simply enduring and of being in a No Man's Land when coming home; their lives had become limited. At the same time they were "connected to care" with good memories of receiving attention from others at the scene of the accident, being taken cared of at the emergency unit and cared for in the ICU. This care made them realise that people are responsible for each other, and they felt comforted but also vulnerable. Finally, they experienced "gratitude for life". This included good memories of being loved together with support from their families at the ICU, wanting to win life back at the nursing ward and acceptance when returning home. The support from their families made them realise that they fit in just as they are.</p> <p>Conclusion</p> <p>When bad memories of a surrealistic world and of being injured are balanced by good ones of care and love with a gratitude for life, there are more possibilities to move on despite an uncertain future following the injury.</p

    Access Impediments to Health Care and Social Services Between Anglophone and Francophone African Immigrants Living in Philadelphia with Respect to HIV/AIDS

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    Objectives To describe the social and cultural differences between Anglophone and Francophone African immigrants which define the impediments that Francophone African immigrants face trying to access health and human services in Philadelphia, Pennsylvania. Methods Surveys and personal interviews were administered to participants in social events, community meetings, and health centers. A Chi-squared analysis was used to contrast the communities. Results Francophone Africans demonstrated less acculturation, education, English fluency, and more legal documentation problems, and thus face greater challenges accessing health care. Anglophone Africans had a higher level of acculturation, fewer language problems, and perceived fewer barriers in accessing health care than Francophone Africans. Conclusions Educating new immigrants, through a more culturally sensitive infectious disease treatment and prevention program, is integral to achieving a higher access and utilization rates of available services; especially in recent Francophone immigrants. A larger study is needed to extend the findings to other cities where immigrants with similar backgrounds or acculturation issues reside

    The Eyes Have It: Sex and Sexual Orientation Differences in Pupil Dilation Patterns

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    Recent research suggests profound sex and sexual orientation differences in sexual response. These results, however, are based on measures of genital arousal, which have potential limitations such as volunteer bias and differential measures for the sexes. The present study introduces a measure less affected by these limitations. We assessed the pupil dilation of 325 men and women of various sexual orientations to male and female erotic stimuli. Results supported hypotheses. In general, self-reported sexual orientation corresponded with pupil dilation to men and women. Among men, substantial dilation to both sexes was most common in bisexual-identified men. In contrast, among women, substantial dilation to both sexes was most common in heterosexual-identified women. Possible reasons for these differences are discussed. Because the measure of pupil dilation is less invasive than previous measures of sexual response, it allows for studying diverse age and cultural populations, usually not included in sexuality research
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