3,387 research outputs found

    Building Babies - Chapter 16

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    In contrast to birds, male mammals rarely help to raise the offspring. Of all mammals, only among rodents, carnivores, and primates, males are sometimes intensively engaged in providing infant care (Kleiman and Malcolm 1981). Male caretaking of infants has long been recognized in nonhuman primates (Itani 1959). Given that infant care behavior can have a positive effect on the infant’s development, growth, well-being, or survival, why are male mammals not more frequently involved in “building babies”? We begin the chapter defining a few relevant terms and introducing the theory and hypotheses that have historically addressed the evolution of paternal care. We then review empirical findings on male care among primate taxa, before focusing, in the final section, on our own work on paternal care in South American owl monkeys (Aotus spp.). We conclude the chapter with some suggestions for future studies.Deutsche Forschungsgemeinschaft (HU 1746/2-1) Wenner-Gren Foundation, the L.S.B. Leakey Foundation, the National Geographic Society, the National Science Foundation (BCS-0621020), the University of Pennsylvania Research Foundation, the Zoological Society of San Dieg

    A mixed methods approach to evaluating community drug distributor performance in the control of neglected tropical diseases

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    BACKGROUND: Trusted literate, or semi-literate, community drug distributors (CDDs) are the primary implementers in integrated preventive chemotherapy (IPC) programmes for Neglected Tropical Disease (NTD) control. The CDDs are responsible for safely distributing drugs and for galvanising communities to repeatedly, often over many years, receive annual treatment, create and update treatment registers, monitor for side-effects and compile treatment coverage reports. These individuals are 'volunteers' for the programmes and do not receive remuneration for their annual work commitment. METHODS: A mixed methods approach, which included pictorial diaries to prospectively record CDD use of time, structured interviews and focus group discussions, was used to triangulate data on how 58 CDDs allocated their time towards their routine family activities and to NTD Programme activities in Uganda. The opportunity costs of CDD time were valued, performance assessed by determining the relationship between time and programme coverage, and CDD motivation for participating in the programme was explored. RESULTS: Key findings showed approximately 2.5 working weeks (range 0.6-11.4 working weeks) were spent on NTD Programme activities per year. The amount of time on NTD control activities significantly increased between the one and three deliveries that were required within an IPC campaign. CDD time spent on NTD Programme activities significantly reduced time available for subsistence and income generating engagements. As CDDs took more time to complete NTD Programme activities, their treatment performance, in terms of validated coverage, significantly decreased. Motivation for the programme was reported as low and CDDs felt undervalued. CONCLUSIONS: CDDs contribute a considerable amount of opportunity cost to the overall economic cost of the NTD Programme in Uganda due to the commitment of their time. Nevertheless, programme coverage of at least 75 %, as required by the World Health Organisation, is not being achieved and vulnerable individuals may not have access to treatment as a consequence of sub-optimal performance by the CDDs due to workload and programmatic factors

    Destabilization of the thermohaline circulation by transient perturbations to the hydrological cycle

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    We reconsider the problem of the stability of the thermohaline circulation as described by a two-dimensional Boussinesq model with mixed boundary conditions. We determine how the stability properties of the system depend on the intensity of the hydrological cycle. We define a two-dimensional parameters' space descriptive of the hydrology of the system and determine, by considering suitable quasi-static perturbations, a bounded region where multiple equilibria of the system are realized. We then focus on how the response of the system to finite-amplitude surface freshwater forcings depends on their rate of increase. We show that it is possible to define a robust separation between slow and fast regimes of forcing. Such separation is obtained by singling out an estimate of the critical growth rate for the anomalous forcing, which can be related to the characteristic advective time scale of the system.Comment: 37 pages, 8 figures, submitted to Clim. Dy

    Resolving the extragalactic hard X-ray background

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    The origin of the hard (2-10 keV) X-ray background has remained mysterious for over 35 years. Most of the soft (0.5-2 keV) X-ray background has been resolved into discrete sources, which are primarily quasars; however, these sources do not have the flat spectral shape required to match the X-ray background spectrum. Here we report the results of an X-ray survey 30 times more sensitive than previous studies in the hard band and four times more sensitive in the soft band. The sources detected in our survey account for at least 75 per cent of the hard X-ray background. The mean X-ray spectrum of these sources is in good agreement with that of the background. The X-ray emission from the majority of the detected sources is unambiguously associated with either the nuclei of otherwise normal bright galaxies or optically faint sources, which could either be active nuclei of dust enshrouded galaxies or the first quasars at very high redshifts.Comment: Nature article in pres

    Exile and Re-Constructing Social Identity in the Gospel of Mark.

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    The aim of this project is to add to the scholarly interpretive discourses surrounding the Gospel of Mark. This dissertation argues that the author of Mark attempts to re-construct social identity. Specifically, Mark deploys Jesus as a narrative method for a socio-cultural identity rectification after the Second Temple’s demise. After the destruction of Jerusalem’s temple, Mark was faced with new social incongruities, namely exile, alienation, and lost socio-communal institutions. I will argue that he was a displaced urban intellectual who mourns his lost social identification markers. However, Mark does not merely lament. Additionally, he provides a means to reconcile and rectify his social identity. Chapter 1 delivers an investigation into the possible dates and locations of Mark’s composition. Examining the social, cultural, and political settings of first-century Palestine, supplies the necessary background of Mark’s socio-historical context. Chapter 2 analyzes theories regarding the concepts of nationality, identity, and exile. I propose that Mark is an example of exilic literature, which can be understood through the larger umbrella of post-colonial literature. Chapter 3 will examine the textual evidence of Mark’s lamentation sentiments. I argue that Mark questions his self-identity through sentiments of social alienation and that he expresses these emotions through lamenting lost socio-cultural institutions. Chapter 4 investigates Mark’s creative intellectual attempts to reconcile his lost social-cultural identifiers. I emphasize that Mark replaces the lost “there” sacred space with a “universal/anywhere” one. Overall, I demonstrate that Mark, as an exilic author, simultaneously laments and reconciles his social incongruities through re-establishing, remoulding, and reconfiguring lost socio-cultural institutions and redefining institutional space

    A systematic review of urine biomarkers in children with IgA vasculitis nephritis

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    Background: Nephritis is a recognised complication of IgA vasculitis (IgAV, Henoch-Schönlein purpura) contributing to 1–2% of all chronic kidney disease (CKD) stage 5. Improved understanding may reduce irreversible damage in IgAV nephritis (IgAV-N). Objective: The aim of this study was to perform a comprehensive systematic literature review to identify promising clinical and pre-clinical urine biomarkers in children with IgAV-N that could predict the presence of nephritis and/or determine its severity. Methods: A systematic literature review was performed using four search engines and a predefined search term strategy. Promising biomarkers were divided in terms of clinical or pre-clinical and ability to predict the presence of nephritis or determine its severity. Results were described using statistical significance (p < 0.05) and area under the curve (AUC) values. Results: One hundred twenty-one studies were identified; 13 were eligible. A total of 2446 paediatric patients were included: healthy controls (n = 761), children with IgAV-N (n = 1236) and children with IgAV without nephritis (IgAV-noN, n = 449). Fifty-one percent were male, median age 7.9 years. The clinical markers, 24-h protein quantity and urine protein:creatinine ratio, were deemed acceptable for assessing severity of nephritis (AUC < 0.8). Urinary albumin concentration (Malb) performed well (AUC 0.81–0.98). The most promising pre-clinical urinary biomarkers in predicting presence of nephritis were as follows: kidney injury molecule-1 (KIM-1) (AUC 0.93), monocyte chemotactic protein-1 (MCP-1) (AUC 0.83), N-acetyl-β-glucosaminidase (NAG) (0.76–0.96), and angiotensinogen (AGT) (AUC not available). Urinary KIM-1, MCP-1, and NAG appeared to correlate with disease severity. Conclusions: Longitudinal studies are needed to assess whether pre-clinical biomarkers enhance standard of care in IgAV-N

    Performance of the CMS Cathode Strip Chambers with Cosmic Rays

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    The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device in the CMS endcaps. Their performance has been evaluated using data taken during a cosmic ray run in fall 2008. Measured noise levels are low, with the number of noisy channels well below 1%. Coordinate resolution was measured for all types of chambers, and fall in the range 47 microns to 243 microns. The efficiencies for local charged track triggers, for hit and for segments reconstruction were measured, and are above 99%. The timing resolution per layer is approximately 5 ns

    Autoimmune and autoinflammatory mechanisms in uveitis

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    The eye, as currently viewed, is neither immunologically ignorant nor sequestered from the systemic environment. The eye utilises distinct immunoregulatory mechanisms to preserve tissue and cellular function in the face of immune-mediated insult; clinically, inflammation following such an insult is termed uveitis. The intra-ocular inflammation in uveitis may be clinically obvious as a result of infection (e.g. toxoplasma, herpes), but in the main infection, if any, remains covert. We now recognise that healthy tissues including the retina have regulatory mechanisms imparted by control of myeloid cells through receptors (e.g. CD200R) and soluble inhibitory factors (e.g. alpha-MSH), regulation of the blood retinal barrier, and active immune surveillance. Once homoeostasis has been disrupted and inflammation ensues, the mechanisms to regulate inflammation, including T cell apoptosis, generation of Treg cells, and myeloid cell suppression in situ, are less successful. Why inflammation becomes persistent remains unknown, but extrapolating from animal models, possibilities include differential trafficking of T cells from the retina, residency of CD8(+) T cells, and alterations of myeloid cell phenotype and function. Translating lessons learned from animal models to humans has been helped by system biology approaches and informatics, which suggest that diseased animals and people share similar changes in T cell phenotypes and monocyte function to date. Together the data infer a possible cryptic infectious drive in uveitis that unlocks and drives persistent autoimmune responses, or promotes further innate immune responses. Thus there may be many mechanisms in common with those observed in autoinflammatory disorders

    Human activities and biodiversity opportunities in pre-industrial cultural landscapes: relevance to conservation

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    1. Conservation practices in Europe frequently attempt to perpetuate or mimic the ‘traditional’ forms of management of semi-natural habitats, but with a limited understanding of what these entailed. 2. We review the emerging understanding of ecological processes, structures and management interventions that enhance biodiversity (wildlife) at diverse scales. These are then examined in the context of pre-industrial (c. 1200-1750) land management systems in lowland England, in order to identify historic practices which are likely to have provided important wildlife resources, but which are relatively neglected in current conservation management. 3. Principles enhancing alpha and beta diversity and the conservation status of threatened species, include: structural complexity and heterogeneity at nested spatial scales; physical disturbance and exposure of mineral substrate; nutrient removal; lengthened successional rotations; and spatial variation in grazing regimes. 4. The available evidence suggests that pre-industrial management was generally characterised by: intense resource exploitation and significant levels of biomass harvest; complex nested structural heterogeneity both between and within landscape elements; overlaying of multiple land-uses; and spatial and temporal variability in management, rendering the concept of long-lived ‘traditional’ practice problematic. Grazing patterns are poorly understood but intensive grazing was probably the norm in most contexts, potentially resulting in simplified sward structures and suppressed ecotonal vegetation. 5. In much of the pre-industrial period, early-successional and disturbed microhabitats were widespread but ungrazed or lightly grazed herb-rich vegetation may have been limited, the converse of current conservation management. The key change since then has been homogenisation at multiple scales, coupled with reduction of specific niches and conditions. 6. Synthesis and applications: In adopting perceived ‘traditional’ management practices, modern conservation rarely achieves the range and complexity of conditions that were present in the past. A better understanding of past practices allows more favourable management of those surviving semi-natural habitats where historic assemblages persist – with greater emphasis on physical disturbance and variability in prescriptions both temporally and spatially. When creating or restoring habitats, after interruption of management sufficiently long for dependent assemblages to be lost, better appreciation of historic management encourages novel forms of intervention to enhance biodiversity, with emphasis on complex structural and spatial heterogeneity at nested scales, biomass removal and nutrient reduction. These two distinct but overlapping approaches are complementary to the use of large herbivores to create and maintain dynamic ecotonal mosaics in the manner advocated by some proponents of ‘rewilding’
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