56 research outputs found

    Metallicities of 0.3<z<1.0 Galaxies in the GOODS-North Field

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    We measure nebular oxygen abundances for 204 emission-line galaxies with redshifts 0.3<z<1.0 in the Great Observatories Origins Deep Survey North (GOODS-N) field using spectra from the Team Keck Redshift Survey (TKRS). We also provide an updated analytic prescription for estimating oxygen abundances using the traditional strong emission line ratio, R_{23}, based on the photoionization models of Kewley & Dopita (2003). We include an analytic formula for very crude metallicity estimates using the [NII]6584/Halpha ratio. Oxygen abundances for GOODS-N galaxies range from 8.2< 12+log(O/H)< 9.1 corresponding to metallicities between 0.3 and 2.5 times the solar value. This sample of galaxies exhibits a correlation between rest-frame blue luminosity and gas-phase metallicity (i.e., an L-Z relation), consistent with L-Z correlations of previously-studied intermediate-redshift samples. The zero point of the L-Z relation evolves with redshift in the sense that galaxies of a given luminosity become more metal poor at higher redshift. Galaxies in luminosity bins -18.5<M_B<-21.5 exhibit a decrease in average oxygen abundance by 0.14\pm0.05 dex from z=0 to z=1. This rate of metal enrichment means that 28\pm0.07% of metals in local galaxies have been synthesized since z=1, in reasonable agreement with the predictions based on published star formation rate densities which show that ~38% of stars in the universe have formed during the same interval. (Abridged)Comment: AASTeX, 49 pages, 16 figures, accepted for publication in The Astrophysical Journa

    Assessing Opportunities to Improve Sedation/Analgesia Use in Neonatal Patients on ECMO

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    Background: Sedation is used during ECMO to prevent agitation. Analgesia is used to dampen pain perception as neonatal procedural pain related stress is associated with later altered neurodevelopment with poorer perceptual reasoning and visual perception. Common sedatives/analgesics used during ECMO are opiates and benzodiazepines. Studies have shown that lipophilic drugs such as Fentanyl and Midazolam are significantly sequestered in the circuit suggesting opportunities to improve delivery for pain. Hypothesis and Methods: We hypothesized opportunities to improve sedation/analgesia drug treatment in ECMO patients. Using a retrospective analysis of all neonatal patients receiving ECMO between 2015-2020, we aimed to assess the relationship between sedative/analgesia type and dose and clinical complications. We identified patient demographics, medication type, dose used, days to wean, length of hospital stay, mortality, medical complications at discharge and MRI results. Results: 49 patients were included, mean gestational age 37.6 wks ±3.6. Seventeen (35%) infants died. Race was not associated with mortality. All patients received Fentanyl and Midazolam with one patient who also received Morphine infusion. Fentanyl and Midazolam dose during ECMO was associated with risk for oxygen at discharge 296 vs 517 mcg/kg/days for Fentanyl (p=0.04), and 358 vs 2598 mcg/kg/days for Midazolam (p=0.002) as well as need for feeding tube at discharge 272 vs 420 mcg/kg/days for Fentanyl (p=0.049) and 1.03 vs 1.60 mg/kg/days for Midazolam(p=0.04). Risk for abnormal MRI was increased with Fentanyl ECMO dose exposure (p=0.016). Male gender was associated with greater fentanyl dose exposure by 27% (p=0.038). Conclusion: Fentanyl and Midazolam increased dose exposure was associated with increased risk for later neurological clinical complications in infants undergoing ECMO. Further studies are needed to assess serum drug concentrations in ECMO patients to better understand development of drug tolerance, circuit sequestration and dose exposure to adjust the therapeutic range of sedation and analgesia use

    Moyo Vol. I N 2

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    JDB. The Bradys On Sex: Any Excuse to Talk About Marsha . 1. Shaver, Anne. One View From Lesbos . 2. Harmless, Heather. In Sex Lies Inequality . 3. Anonymous. Mom and Dad, I Was Raped: The Account of One Anonymous Denison Woman . 4. Cockrell, Kim. When Ebony & Ivory Consumate: Interracial Sex . Perry, Christian. The State\u27s Permission? . 8. Benboe, Daniel. Fact or Fiction? 8. Gerding, Dale N. STDs: Are You At Risk? . 9. Smith, N. Confessions of A Nymphomaniac . 10. Dunham, Trey. “Sex and God”. 15. Fore, Kevin. Straight Talk on Homosexuality . 16. Sherman, Nancy. Sex, Booze, and the Swedish Bikini Team . 19. Wetterqvist, Christoffer. Tall, Blond, and Beautiful: Sex from a Swedish perspective . 20. Moore, Sheryn. AIDS & College . 21. Benboe, Daniel. Lover\u27s Dilema . 21. Ransdell, Lisa. Burnout and the Good Fight: Fourteen years in the Anti-Rape Movement . 22

    Variability in age and size at maturation, reproductive longevity, and long-term growth dynamics for Kemp's ridley sea turtles in the Gulf of Mexico

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    Effective management of protected sea turtle populations requires knowledge not only of mean values for demographic and life-history parameters, but also temporal and spatial trends, variability, and underlying causes. For endangered Kemp's ridley sea turtles (Lepidochelys kempii), the need for baseline information of this type has been emphasized during attempts to understand causes underlying the recent truncation in the recovery trajectory for nesting females. To provide insight into variability in age and size at sexual maturation (ASM and SSM) and long-term growth patterns likely to influence population trends, we conducted skeletochronological analysis of humerus bones from 333 Kemp's ridleys stranded throughout the Gulf of Mexico (GOM) from 1993 to 2010. Ranges of possible ASMs (6.8 to 21.8 yr) and SSMs (53.3 to 68.3 cm straightline carapace length (SCL)) estimated using the "rapprochement" skeletal growth mark associated with maturation were broad, supporting incorporation of a maturation schedule in Kemp's ridley population models. Mean ASMs estimated from rapprochement and by fitting logistic, generalized additive mixed, and von Bertalanffy growth models to age and growth data ranged from 11 to 13 yr; confidence intervals for the logistic model predicted maturation of 95% of the population between 11.9 and 14.8 yr. Early juvenile somatic growth rates in the GOM were greater than those previously reported for the Atlantic, indicating potential for differences in maturation trajectories between regions. Finally, long-term, significant decreases in somatic growth response were found for both juveniles and adults, which could influence recruitment to the reproductive population and observed nesting population trends

    Coral restoration in a changing world - a global synthesis of methods and techniques

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    Coral reef ecosystems have suffered an unprecedented loss of habitat-forming hard corals in recent decades, due to increased nutrient outputs from agriculture, elevated levels of suspended sediment caused by deforestation and development, destructive fishing practices, over-harvesting of reef species, outbreaks of corallivorous crown-of-thorns starfish (COTS, Acanthaster planci), coral disease and tropical storms. However, in recent years climate change has emerged as the primary threat to coral reefs. While reefs have a natural capacity for recovery, recurring events like mass coral bleaching and extreme weather events is increasing in frequency, intensity and severity, and are eroding the time for recovery between catastrophic events. Marine conservation has primarily focused on passive habitat protection over active restoration, in contrast to terrestrial ecosystems where active restoration is common practice. Further, active restoration is well accepted for wetlands and shellfish reefs however coral reef restoration has remained controversial both in academia and amongst marine managers. This is despite recent research suggesting that optimal conservation outcomes include both habitat protection and restoration. Critics often argue that coral restoration detracts focus from mitigating climate change and other threats to the marine environment, while proponents of coral restoration counter that interventions can serve to protect coral biodiversity and endangered species in the short-term, while mitigation of large-scale threats such as climate change and water quality take effect. Despite this disconnect between coral restoration practitioners, coral reef managers and scientists, active coral restoration is increasingly used as a tool to attempt to restore coral populations. The field has largely developed through independent work of isolated groups, and has fallen victim to ‘growing pains’ associated with ecological restoration in many other ecosystems. Partly this is due to a reluctance to share outcomes of projects, and in some cases a lack of monitoring or appropriate reporting of project outcomes. To mitigate this, we aimed to synthesise the available knowledge in a comprehensive global review of coral restoration methods, incorporating data from a traditional literature search of the scientific literature, complemented with information gathered from online sources and through a survey of coral restoration practitioners. We identified 329 case studies on coral restoration, of which 195 were from the scientific literature, 79 were sourced from the grey literature (i.e. reports and online descriptions), and 55 were responses to our survey of restoration practitioners. We identified ten coral restoration intervention types: coral gardening - transplantation phase (23% of records), direct transplantation (21%), artificial reefs (19%), coral gardening - nursery phase (17%), coral gardening (both phases, 7%), substrate enhancement with electricity (4%), substrate stabilisation (4%), algae removal (2%), larval enhancement (1%) and microfragmentation (<1%). The majority of interventions involve coral fragmentation or transplantation of coral fragments (70%). While 52 countries are represented in the dataset, the majority of projects were conducted in the USA, Philippines, Thailand and Indonesia (together representing 40% of projects). Coral restoration case studies are dominated by short-term projects, with 66% of all projects reporting less than 18 months of monitoring of the restored sites. Overall, the median length of projects was 12 months. Similarly, most projects are relatively small in spatial scale, with a median size of restored area of 500 m2. A diverse range of species are represented in the dataset, with 221 different species from 89 coral genera. Overall, coral restoration projects focused primarily (65% of studies) on fast-growing branching corals. Among all the published documents, the top five species (22% of studies) were Acropora cervicornis, Pocillopora damicornis, Stylophora pistillata, Porites cylindrica and Acropora palmata. Over a quarter of projects (26%) involved the coral genus Acropora, while 9% of studies included a single species - Acropora cervicornis. Much of the focus on Acropora cervicornis and Acropora palmata is likely to have resulted from these important reef-forming species being listed as threatened on the United States Endangered Species List and as Endangered on the International Union for Conservation of Nature Red List of Endangered Species (IUCN 2018). We have dedicated a section to each intervention type covered in this review, and describe the potential and limitations of each intervention type in detail there. However, collating this information has highlighted the following main points which apply to coral restoration in general. 1. On average, survival in restored corals is relatively high. All coral genera with sufficient replication from which to draw conclusions (>10 studies listing that genus) report an average survival between 60-70%. 2. Differences in survival and growth are largely species and/or location specific, so the selection of specific methods should be tailored to the local conditions, costs, availability of materials, and to the specific objectives of each project. 3. Projects are overall small and short, however substantial scaling up is required for restoration to be a useful tool in supporting the persistence of reefs in the future. While there is ample evidence detailing how to successfully grow corals at smaller scales, few interventions demonstrate a capacity to be scaled up much beyond one hectare. Notable exceptions include methods which propagate sexually derived coral larvae. 4. To date, coral restoration has been plagued by the same common problems as ecological restoration in other ecosystems. Mitigating these will be crucial to successfully scale up projects, and to retain public trust in restoration as a tool for resilience based management. a. Lack of clear objectives - There is a clear mismatch between the stated objectives of projects, and the design of projects and monitoring of outcomes. Poorly articulated or overinflated objectives risk alienating the general public and scientists, by over-promising and under-delivering. Social and economic objectives have inherent value and do not need to be disguised with ecological objectives. b. Lack of appropriate monitoring - A large proportion of projects do not monitor metrics relevant to their stated objectives, or do not continue monitoring for long enough to provide meaningful estimates of success. Further, there is a clear need for standardisation in the metrics that are used, to allow comparisons between projects. c. Lack of appropriate reporting - The outcomes of a large proportion of projects are not documented, which restricts knowledge-sharing and adaptive learning. While we attempted to access some of the unreported projects through our survey, it is clear we have only scratched the surface of existing knowledge. d. Poorly designed projects - An effect of inadequate monitoring and reporting is that projects are poorly suited to their specific area and conditions. Improved knowledge-sharing and development of best practice coral restoration guidelines aims to mitigate this problem

    Coral restoration – a systematic review of current methods, successes, failures and future directions

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    Coral reef ecosystems have suffered an unprecedented loss of habitat-forming hard corals in recent decades. While marine conservation has historically focused on passive habitat protection, demand for and interest in active restoration has been growing in recent decades. However, a disconnect between coral restoration practitioners, coral reef managers and scientists has resulted in a disjointed field where it is difficult to gain an overview of existing knowledge. To address this, we aimed to synthesise the available knowledge in a comprehensive global review of coral restoration methods, incorporating data from the peer-reviewed scientific literature, complemented with grey literature and through a survey of coral restoration practitioners. We found that coral restoration case studies are dominated by short-term projects, with 60% of all projects reporting less than 18 months of monitoring of the restored sites. Similarly, most projects are relatively small in spatial scale, with a median size of restored area of 100 m2. A diverse range of species are represented in the dataset, with 229 different species from 72 coral genera. Overall, coral restoration projects focused primarily on fast-growing branching corals (59% of studies), and report survival between 60 and 70%. To date, the relatively young field of coral restoration has been plagued by similar 'growing pains' as ecological restoration in other ecosystems. These include 1) a lack of clear and achievable objectives, 2) a lack of appropriate and standardised monitoring and reporting and, 3) poorly designed projects in relation to stated objectives. Mitigating these will be crucial to successfully scale up projects, and to retain public trust in restoration as a tool for resilience based management. Finally, while it is clear that practitioners have developed effective methods to successfully grow corals at small scales, it is critical not to view restoration as a replacement for meaningful action on climate change

    Parental attributions of control for child behaviour and their relation to discipline practices in parents of children with and without developmental delays

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    Children with developmental delays (DD) are at risk for developing behavior problems. Research suggests that parents’ causal attributions for child behavior are related to parenting. This study investigated this association in parents of children with DD compared to parents of typically developing (TD) children. It specifically focused on attributions of child control by separating these from attributions of responsibility, blame and intent, and from attributions of parent control and responsibility. Fifty-one parents of children with DD and 69 parents of TD children completed two questionnaires. The Written Analogue Questionnaire measured causal attributions. The Parenting Scale measured dysfunctional discipline practices. Parents of children with DD viewed the child’s role in problematic behavior more positively while also viewing misbehavior as more fixed than parents of TD children. Parents of TD children who viewed their child as more in control over misbehavior used less dysfunctional discipline, but this association was not found for parents of children with DD. The results advance understanding of how parents perceive behavior problems in children with DD and the important role these perceptions play in parental behavior management strategies. More importantly, these perceptions relate to discipline practices differently for parents of children with DD compared to parents of TD children, highlighting that parent interventions should be adapted to the specific needs of parents of children with DD

    Identity Issues : Situating the Self in Contemporary Native American Literature

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    The following work is an examination of the way in which Contemporary Native American authors from the United States depict the search for self within their novels. Included in this thesis is an 'Introduction' that examines the development of a sense of identity that is unique to Nat!ve Americans, as well as those factors that shape and in some instances, hinder the development ofsuch a self-perception, such as stereotypes and US government policies. In order to provide a thorough examination of this particular topic, this work examines novels from three Native American authors with varying tribal backgrounds and experiences. These authors include Sherman Alexie, Susan Power and Greg Sarris. As each of these authors has vastly different ties and levels of involvement with their particular Native American heritages, this work is able to examine the differences that arise in the development ofNative self-perceptions when faced with environmental and social variances. In doing so, this work not only highlights the many different forms that Native American self-perceptions take, but also the multiple paths that lead to the development of these identities.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
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