86 research outputs found

    Field Guide to a Hybrid Landscape

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    In Field Guide to a Hybrid Landscape Dana Fritz traces the evolution of the Bessey Ranger District and Nursery of the Nebraska National Forest and Grasslands. Fritz’s contemporary photographs of this unique ecosystem, with provocative environmental essays, maps, and historical photographs from the U.S. Forest Service archives, illuminate the complex environmental and natural history of the site, especially as it relates to built environments, land use, and climate change. The Nebraska National Forest at Halsey, as it is known colloquially, is the largest hand-planted forest in the Western Hemisphere, and formerly in the world. This hybrid landscape of a conifer forest overlaid onto a semiarid grassland just west of the one-hundredth meridian was an ambitious late nineteenth-century idea to create a timber industry, to reclaim a landscape considered disordered and unproductive, and to change the local climate in northcentral Nebraska. While the planners seemed not to appreciate the native grasslands that form the ecosystem of the Nebraska Sandhills, they did recognize the reliable water from the Dismal and Middle Loup Rivers that border the site. In 1902 the first federal nursery was established as part of the Dismal River Forest Reserve to produce seedlings for plains homesteads and the adjacent treeless tract of land. At that time tree planting was not used for carbon sequestration but to mitigate the wind and evaporation of moisture. The Bessey Nursery now produces replacement seedlings for burned and beetle-damaged forests in the Rocky Mountains and for the Nebraska Conservation Trees Program. This constructed landscape of row-crop trees that were protected from fire for decades, yet never commercially harvested for timber, provides a rich metaphor for current environmental predicaments. The late nineteenth-century effort to reclaim with trees what was called the Great American Desert has evolved to a focus on twenty-first-century conservation, grassland restoration, and reforestation, all of which work to sequester carbon, maintain natural ecosystem balance, and mitigate large-scale climate change. Field Guide to a Hybrid Landscape offers a visual and critical examination of this unique managed landscape, which has implications far beyond its borders. 144 pages 78 photographs, 2 illustrations, 9 maps This book is available from University of Nebraska Press: https://www.nebraskapress.unl.edu/bison-books/9781496227775

    Earliest Archaeological Evidence of Persistent Hominin Carnivory

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    The emergence of lithic technology by ∼2.6 million years ago (Ma) is often interpreted as a correlate of increasingly recurrent hominin acquisition and consumption of animal remains. Associated faunal evidence, however, is poorly preserved prior to ∼1.8 Ma, limiting our understanding of early archaeological (Oldowan) hominin carnivory. Here, we detail three large well-preserved zooarchaeological assemblages from Kanjera South, Kenya. The assemblages date to ∼2.0 Ma, pre-dating all previously published archaeofaunas of appreciable size. At Kanjera, there is clear evidence that Oldowan hominins acquired and processed numerous, relatively complete, small ungulate carcasses. Moreover, they had at least occasional access to the fleshed remains of larger, wildebeest-sized animals. The overall record of hominin activities is consistent through the stratified sequence – spanning hundreds to thousands of years – and provides the earliest archaeological evidence of sustained hominin involvement with fleshed animal remains (i.e., persistent carnivory), a foraging adaptation central to many models of hominin evolution

    Earliest archaeological evidence of persistent hominin carnivory

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    The emergence of lithic technology by ~2.6 million years ago (Ma) is often interpreted as a correlate of increasingly recurrent hominin acquisition and consumption of animal remains. Associated faunal evidence, however, is poorly preserved prior to ~1.8 Ma, limiting our understanding of early archaeological (Oldowan) hominin carnivory. Here, we detail three large well-preserved zooarchaeological assemblages from Kanjera South, Kenya. The assemblages date to ~2.0 Ma, pre-dating all previously published archaeofaunas of appreciable size. At Kanjera, there is clear evidence that Oldowan hominins acquired and processed numerous, relatively complete, small ungulate carcasses. Moreover, they had at least occasional access to the fleshed remains of larger, wildebeest-sized animals. The overall record of hominin activities is consistent through the stratified sequence ??? spanning hundreds to thousands of years ??? and provides the earliest archaeological evidence of sustained hominin involvement with fleshed animal remains (i.e., persistent carnivory), a foraging adaptation central to many models of hominin evolution.This research was supported by funding from the National Science Foundation, Leakey Foundation, Wenner-Gren Foundation, National Geographic Society, The Leverhulme Trust, University of California, Baylor University, and the City University of New York. Additional logistical support was provided by the Smithsonian Institution???s Human Origins Program and the Peter Buck Fund for Human Origins Research, the British Institute in Eastern Africa, and the National Museums of Kenya. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    First-Year Spectroscopy for the SDSS-II Supernova Survey

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    This paper presents spectroscopy of supernovae discovered in the first season of the Sloan Digital Sky Survey-II Supernova Survey. This program searches for and measures multi-band light curves of supernovae in the redshift range z = 0.05 - 0.4, complementing existing surveys at lower and higher redshifts. Our goal is to better characterize the supernova population, with a particular focus on SNe Ia, improving their utility as cosmological distance indicators and as probes of dark energy. Our supernova spectroscopy program features rapid-response observations using telescopes of a range of apertures, and provides confirmation of the supernova and host-galaxy types as well as precise redshifts. We describe here the target identification and prioritization, data reduction, redshift measurement, and classification of 129 SNe Ia, 16 spectroscopically probable SNe Ia, 7 SNe Ib/c, and 11 SNe II from the first season. We also describe our efforts to measure and remove the substantial host galaxy contamination existing in the majority of our SN spectra.Comment: Accepted for publication in The Astronomical Journal(47pages, 9 figures

    River ecosystem conceptual models and non‐perennial rivers: A critical review

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    Conceptual models underpin river ecosystem research. However, current models focus on continuously flowing rivers and few explicitly address characteristics such as flow cessation and drying. The applicability of existing conceptual models to nonperennial rivers that cease to flow (intermittent rivers and ephemeral streams, IRES) has not been evaluated. We reviewed 18 models, finding that they collectively describe main drivers of biogeochemical and ecological patterns and processes longitudinally (upstream-downstream), laterally (channel-riparian-floodplain), vertically (surface water-groundwater), and temporally across local and landscape scales. However, perennial rivers are longitudinally continuous while IRES are longitudinally discontinuous. Whereas perennial rivers have bidirectional lateral connections between aquatic and terrestrial ecosystems, in IRES, this connection is unidirectional for much of the time, from terrestrial-to-aquatic only. Vertical connectivity between surface and subsurface water occurs bidirectionally and is temporally consistent in perennial rivers. However, in IRES, this exchange is temporally variable, and can become unidirectional during drying or rewetting phases. Finally, drying adds another dimension of flow variation to be considered across temporal and spatial scales in IRES, much as flooding is considered as a temporally and spatially dynamic process in perennial rivers. Here, we focus on ways in which existing models could be modified to accommodate drying as a fundamental process that can alter these patterns and processes across spatial and temporal dimensions in streams. This perspective is needed to support river science and management in our era of rapid global change, including increasing duration, frequency, and occurrence of drying.info:eu-repo/semantics/publishedVersio

    Antenatal Periviability Counseling and Decision Making: A Retrospective Examination by the Investigating Neonatal Decisions for Extremely Early Deliveries Study Group

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    Objective To describe periviability counseling practices and decision making. Study Design This is a retrospective review of mothers and newborns delivering between 22 and 24 completed weeks from 2011 to 2015 at six U.S. centers. Maternal and fetal/neonatal clinical and maternal sociodemographic data from medical records and geocoded sociodemographic information were collected. Separate analyses examined characteristics surrounding receiving neonatology consultation; planning neonatal resuscitation; and centers' planned resuscitation rates. Results Neonatology consultations were documented for 40, 63, and 72% of 498 mothers delivering at 22, 23, and 24 weeks, respectively. Consult versus no-consult mothers had longer median admission-to-delivery intervals (58.7 vs. 8.7 h, p < 0.001). Consultations were seen more frequently when parental decision making was evident. In total, 76% of mothers had neonatal resuscitation planned. Resuscitation versus no-resuscitation newborns had higher mean gestational ages (24.0 vs. 22.9 weeks, p < 0.001) and birthweights (618 vs. 469 g, p < 0.001). Planned resuscitation rates differed at higher (HR) versus lower (LR) rate centers at 22 (43 vs. 7%, p < 0.001) and 23 (85 vs. 58%, p < 0.001) weeks. HR versus LR centers' populations had more socioeconomic hardship markers but fewer social work consultations (odds ratio: 0.31; confidence interval: 0.15–0.59, p < 0.001). Conclusion Areas requiring improvement included delivery/content of neonatology consultations, social work support, consideration of centers' patient populations, and opportunities for shared decisions

    Intention to treat: obstetrical management at the threshold of viability

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    Background Despite medical advances in the care of extremely preterm neonates and growing acceptance of resuscitation at 23 and even 22 weeks gestation, controversy remains concerning the use of antepartum obstetric intervention s that are intended to improve outcomes in the setting of anticipated extremely preterm birth. In the absence of demonstrated benefit at <23 weeks gestation and with uncertain benefit at 23 weeks gestation, previous obstetric committee opinions have advised against their use at these gestational ages. Objective The purpose of this study was to review the use of obstetric intervention s at the threshold of viability based on neonatal resuscitation plan and to review the odds of survival to neonatal intensive care unit discharge based on use of obstetric intervention s with adjustment for neonatal factors. Study Design This retrospective study of 6 study centers reviewed pregnant patients who were admitted between 22+0/7 and 24+6/7 weeks gestation facing delivery from 2011–2015. Patients with known anomalies or missing data were excluded. Records were reviewed for demographics, resuscitation plan, and obstetric intervention s. Mode of delivery, delivery room care, and final infant dispositions were recorded. Multiple gestations were included as 1 pregnancy in regard to the use of obstetric intervention s and were excluded from survival analysis. Results Four hundred seventy-eight mothers met the inclusion criteria. When resuscitation was planned, mothers were more likely to receive all conventional obstetric intervention s (antenatal steroids, magnesium sulfate for neuroprotection, tocolytics, and Group Beta Streptococcus prophylaxis), regardless of gestational age at admission, and were more likely to be delivered by cesarean section (P<.05). Analyzed as a group, when antenatal steroids, magnesium sulfate, tocolytics and Group Beta Streptococcus prophylaxis were administered, the odds of survival to neonatal intensive care unit discharge increased for newborn infants who were born at 22 (odds ratio, 11.33; 95% confidence interval, 1.405–91.4) and 23 weeks gestation (odds ratio, 15.5; 95% confidence interval, 3.747-64.11; P<.05). In singletons, the odds of survival to neonatal intensive care unit discharge was not improved by cesarean delivery vs vaginal delivery, even after adjustment for the use of additional interventions, weight, gender, and gestational age (odds ratio, 1.0; 95% confidence interval, 0.59–1.8; P=.912). Conclusion In this study, when postnatal resuscitation was planned at 22 and 23 weeks gestation, women were more likely to receive antenatal steroids, magnesium sulfate, and antibiotics; provision of this bundle imparted survival benefit at 23 weeks gestation but could not be demonstrated at 22 weeks gestation because of the small sample size. These findings support of neonate-oriented obstetric interventions in the setting of delivery at 23 weeks gestation when resuscitation is planned and further exploration of optimal obstetric care when resuscitation of infants who were born at 22 weeks gestation is anticipated

    Evaluation of a multiple ecological level child obesity prevention program: Switch® what you Do, View, and Chew

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    <p>Abstract</p> <p>Background</p> <p>Schools are the most frequent target for intervention programs aimed at preventing child obesity; however, the overall effectiveness of these programs has been limited. It has therefore been recommended that interventions target multiple ecological levels (community, family, school and individual) to have greater success in changing risk behaviors for obesity. This study examined the immediate and short-term, sustained effects of the Switch program, which targeted three behaviors (decreasing children's screen time, increasing fruit and vegetable consumption, and increasing physical activity) at three ecological levels (the family, school, and community).</p> <p>Methods</p> <p>Participants were 1,323 children and their parents from 10 schools in two states. Schools were matched and randomly assigned to treatment and control. Measures of the key behaviors and body mass index were collected at baseline, immediately post-intervention, and 6 months post-intervention.</p> <p>Results</p> <p>The effect sizes of the differences between treatment and control groups ranged between small (Cohen's <it>d </it>= 0.15 for body mass index at 6 months post-intervention) to large (1.38; parent report of screen time at 6 months post-intervention), controlling for baseline levels. There was a significant difference in parent-reported screen time at post-intervention in the experimental group, and this effect was maintained at 6 months post-intervention (a difference of about 2 hours/week). The experimental group also showed a significant increase in parent-reported fruit and vegetable consumption while child-reported fruit and vegetable consumption was marginally significant. At the 6-month follow-up, parent-reported screen time was significantly lower, and parent and child-reported fruit and vegetable consumption was significantly increased. There were no significant effects on pedometer measures of physical activity or body mass index in the experimental group. The intervention effects were moderated by child sex (for fruit and vegetable consumption, physical activity, and weight status), family involvement (for fruit and vegetable consumption), and child body mass index (for screen time). The perception of change among the experimental group was generally positive with 23% to 62% indicating positive changes in behaviors.</p> <p>Conclusion</p> <p>The results indicate that the Switch program yielded small-to-modest treatment effects for promoting children's fruit and vegetable consumption and minimizing screen time. The Switch program offers promise for use in youth obesity prevention.</p

    Genetic correlation between amyotrophic lateral sclerosis and schizophrenia

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    A. Palotie on työryhmän Schizophrenia Working Grp Psychiat jäsen.We have previously shown higher-than-expected rates of schizophrenia in relatives of patients with amyotrophic lateral sclerosis (ALS), suggesting an aetiological relationship between the diseases. Here, we investigate the genetic relationship between ALS and schizophrenia using genome-wide association study data from over 100,000 unique individuals. Using linkage disequilibrium score regression, we estimate the genetic correlation between ALS and schizophrenia to be 14.3% (7.05-21.6; P = 1 x 10(-4)) with schizophrenia polygenic risk scores explaining up to 0.12% of the variance in ALS (P = 8.4 x 10(-7)). A modest increase in comorbidity of ALS and schizophrenia is expected given these findings (odds ratio 1.08-1.26) but this would require very large studies to observe epidemiologically. We identify five potential novel ALS-associated loci using conditional false discovery rate analysis. It is likely that shared neurobiological mechanisms between these two disorders will engender novel hypotheses in future preclinical and clinical studies.Peer reviewe
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