Carbon and nitrogen assimilation in the Bering Sea clams Nuculana radiata and Macoma moesta

We analyzed bulk carbon and nitrogen stable isotope values (delta C-13 and delta N-15) of the benthic clams Nuculana radiata and Macoma moesta from the Bering Sea during controlled feeding experiments (spring of 2009 and 2010) using isotopically labeled sea ice algae. The aim was to determine the ability of these clam species to assimilate carbon and nitrogen from sea ice algae. Specimens were collected in the Bering Sea and placed into jars without sediment (2009, N. radiata only) or into natural sediment cores (2010, both species). The clams were offered isotopically enriched (both C and N) or non-enriched algal feeds for time periods of 42 (2009) and 18 d (2010). Isotopic assimilation rates for carbon and nitrogen were calculated using the change in the isotope ratios of the clams over the experimental time. N. radiata in the jar experiments had slow isotopic assimilation rates (0.01 to 0.23 parts per thousand d(-1)), with solvent-extractable organic matter/lipids taking up both of the isotope markers fastest and muscle tissue the slowest. Lipids may thus be particularly suitable to track the immediate ingestion of sea ice algal production in benthic consumers. M. moesta showed 30% higher isotopic assimilation compared to N. radiata in sediment cores, likely reflecting the different feeding behaviors of these two species. Based on our results, N. radiata is likely better able to utilize food sources buried in the sediment and may be more competitive over the sediment surface feeding M. moesta under conditions of reduced ice algal production in the northern Bering Sea. (C) 2012 Elsevier B.V. All rights reserved.This project was undertaken as a part of the National Science Foundation funded Bering Sea Ecosystem Study (BEST Project) #0732767awarded to R. Gradinger, K. Iken, and B. Bluhm at the University of Alaska Fairbanks. Additional research funding to J. Weems was provided by the UAF Center for Global Change Student Research Grant with funds from the Cooperative Institute for Alaska Research and the Harland and Genevieve Emerson Foundation of Adel, Iowa. Bering Sea field support and operations in 2009 and 2010 were provided by chief scientists L. Cooper, J. Grebmeier, and C. Ashjian, and the vessels and crews of the United States Coast Guard Cutters Healy and Polar Sea. Additionally, field and laboratory aid was provided by B. Bluhm, M. Kaufman, B. McConnell, M. Schuster, and J. von Meltzer. Services rendered by the Alaska Stable Isotope Facility and its staff, N. Haubenstock and T. Howe, were very much appreciated. Academic support for J. Weems was provided by the School of Fisheries and Ocean Sciences at the University of Alaska Fairbanks. We thank M. Castellini and two anonymous reviewers for comments on earlier versions of this manuscript. Support for the fatty acid analyses and partial support forWooller came from NSF grant ARC 0902177 awarded to (Gradinger, Iken and Wooller). [ST]Ye

Assessment and forecasting of lightning potential and its effect on launch operations at Cape Canaveral Air Force Station and John F. Kennedy Space Center

Lightning plays a pivotal role in the operation decision process for space and ballistic launches at Cape Canaveral Air Force Station and Kennedy Space Center. Lightning forecasts are the responsibility of Detachment 11, 4th Weather Wing's Cape Canaveral Forecast Facility. These forecasts are important to daily ground processing as well as launch countdown decisions. The methodology and equipment used to forecast lightning are discussed. Impact on a recent mission is summarized

Short oestrous cycles in sheep during anoestrus involve defects in progesterone biosynthesis and luteal neovascularisation

Anoestrous ewes can be induced to ovulate by the socio-sexual, 'ram effect'. However, in some ewes the induced ovulation is followed by an abnormally short luteal phase causing a so called, "short cycle". The defect responsible for this luteal dysfunction has not been identified. In this experiment we investigated ovarian and uterine factors implicated in male-induced short cycles in anoestrus ewes using a combined endocrine and molecular strategy. Prior to ovulation, we were able to detect a moderate loss of thecal expression of steroid acute regulatory protein (STAR) in ewes that had not received progesterone priming (which prevents short cycles). At and following ovulation we were able to identify significant loss of expression of genes coding key proteins involved in the biosynthesis of progesterone (STAR, CYP11A1, HSD3B) as well as genes coding proteins critical for vascular development during early luteal development (VEGFA, VEGFR2) suggesting dysfunction in at least two pathways critical for normal luteal function. Furthermore, these changes were associated with a significant reduction of progesterone production and luteal weight. Additionally, we cast doubt on the proposed uterine-mediated effect of prostaglandin F2α as a cause of short cycles by demonstrating both the dysregulation of luteal expression of the PGF receptor, which mediates the luteal effects of PGF2α, and by finding no significant changes in the circulating concentrations of PGFM, the principal metabolite of PGF2α in ewes with short cycles. This study is the first of its kind to examine concurrently, the endocrine and molecular events in the follicular and early luteal stages of the short cycle

Using step width to compare locomotor biomechanics between extinct, non-avian theropod dinosaurs and modern obligate bipeds

How extinct, non-avian theropod dinosaurs locomoted is a subject of considerable interest, as is the manner in which it evolved on the line leading to birds. Fossil footprints provide the most direct evidence for answering these questions. In this study, step width—the mediolateral (transverse) distance between successive footfalls—was investigated with respect to speed (stride length) in non-avian theropod trackways of Late Triassic age. Comparable kinematic data were also collected for humans and 11 species of ground-dwelling birds. Permutation tests of the slope on a plot of step width against stride length showed that step width decreased continuously with increasing speed in the extinct theropods (p < 0.001), as well as the five tallest bird species studied (p < 0.01). Humans, by contrast, showed an abrupt decrease in step width at the walk–run transition. In the modern bipeds, these patterns reflect the use of either a discontinuous locomotor repertoire, characterized by distinct gaits (humans), or a continuous locomotor repertoire, where walking smoothly transitions into running (birds). The non-avian theropods are consequently inferred to have had a continuous locomotor repertoire, possibly including grounded running. Thus, features that characterize avian terrestrial locomotion had begun to evolve early in theropod history

Alcohol Consumption by Aging Adults in the United States: Health Benefits and Detriments

The most rapidly growing segment of the US population is that of older adults (≥65 years). Trends of aging adults (those aged ≥50 years) show that fewer women than men consume alcohol, women consume less alcohol than men, and total alcohol intake decreases after retirement. A U- or J-shaped relationship between alcohol intake and mortality exists among middle-aged (age 45 to 65 years) and older adults. Thus, alcohol can be considered either a tonic or a toxin in dose-dependent fashion. Active areas of research regarding the possible benefits of moderate alcohol consumption among aging individuals include oxidative stress, dementia, psychosocial functioning, dietary contributions, and disease prevention. Yet, due to the rising absolute number of older adults, there may be a silent epidemic of alcohol abuse in this group. Dietary effects of moderate and excessive alcohol consumption are reviewed along with mechanisms by which alcohol or phytochemicals modify physiology, mortality, and disease burden. Alcohol pharmacokinetics is considered alongside age-related sensitivities to alcohol, drug interactions, and disease-related physiological changes. International guidelines for alcohol consumption are reviewed and reveal that many nations lack guidelines specific to older adults. A review of national guidelines for alcohol consumption specific to older adults (eg, those offered by the National Institute on Alcohol Abuse) suggests that they may be too restrictive, given the current literature. There is need for greater quantification and qualification of per capita consumption, consumption patterns (quantity, frequency, and stratified combinations), and types of alcohol consumed by older adults in the United States

Final design of a space debris removal system

The objective is the removal of medium sized orbital debris in low Earth orbits. The design incorporates a transfer vehicle and a netting vehicle to capture the medium size debris. The system is based near an operational space station located at 28.5 degrees inclination and 400 km altitude. The system uses ground based tracking to determine the location of a satellite breakup or debris cloud. This data is unloaded to the transfer vehicle, and the transfer vehicle proceeds to rendezvous with the debris at a lower altitude parking orbit. Next, the netting vehicle is deployed, tracks the targeted debris, and captures it. After expending the available nets, the netting vehicle returns to the transfer vehicle for a new netting module and continues to capture more debris in the target area. Once all the netting modules are expended, the transfer vehicle returns to the space station's orbit, where it is resupplied with new netting modules from a space shuttle load. The new modules are launched by the shuttle from the ground, and the expended modules are taken back to Earth for removal of the captured debris, refueling, and repacking of the nets. Once the netting modules are refurbished, they are taken back into orbit for reuse. In a typical mission, the system has the ability to capture 50 pieces of orbital debris. One mission will take about six months. The system is designed to allow for a 30 degree inclination change on the outgoing and incoming trips of the transfer vehicle

Polyurethane Microparticles for Stimuli Response and Reduced Oxidative Degradation in Highly Porous Shape Memory Polymers

Shape memory polymers (SMPs) have been found to be promising biomaterials for a variety of medical applications; however, the clinical translation of such technology is dependent on tailorable properties such as gravimetric changes in degradation environments. For SMPs synthesized from amino-alcohols, oxidation resulting in rapid mass loss may be problematic in terms of loss of material functionality as well as toxicity and cytocompatibility concerns. Control of gravimetric changes was achieved through the incorporation of small molecule antioxidants, either directly into the polymer matrix or included in microparticles to form a SMP composite material. Direct incorporation of small molecule antioxidants, such as phenolic alcohols, was found to alter shape memory attributes and increase elastic modulus at the expense of the strain to failure. Such changes could not ensure retention of the antioxidants and therefore did not increase oxidative stability. However, the inclusion of antioxidants in microparticles was found to produce materials with similar thermomechanical and shape memory properties while increasing oxidative resistance compared to controls. The microparticle composite SMPs also act as a platform for environmental sensing, such as pH-dependent fluorescence shifts and payload release, as demonstrated by fluorescent dyes and the release of antioxidants. The use of polyurethane-urea microparticles in porous SMPs is demonstrated to increase biostability of the materials, by approximately 25%, and ultimately extend their lifespan for use in aneurysm occlusion as determined through calculated in vivo degradation rates corresponding to a porcine aneurysm environment

Development of a novel observational measure for anxiety in young children: The Anxiety Dimensional Observation Scale

Background Identifying anxiety disorders in preschool-age children represents an important clinical challenge. Observation is essential to clinical assessment and can help differentiate normative variation from clinically significant anxiety. Yet, most anxiety assessment methods for young children rely on parent-reports. The goal of this article is to present and preliminarily test the reliability and validity of a novel observational paradigm for assessing a range of fearful and anxious behaviors in young children, the Anxiety Dimensional Observation Schedule (Anx-DOS). Methods A diverse sample of 403 children, aged 3 to 6 years, and their mothers was studied. Reliability and validity in relation to parent reports (Preschool Age Psychiatric Assessment) and known risk factors, including indicators of behavioral inhibition (latency to touch novel objects) and attention bias to threat (in the dot-probe task) were investigated. Results The Anx-DOS demonstrated good inter-rater reliability and internal consistency. Evidence for convergent validity was demonstrated relative to mother-reported separation anxiety, social anxiety, phobic avoidance, trauma symptoms, and past service use. Finally, fearfulness was associated with observed latency and attention bias toward threat. Conclusions Findings support the Anx-DOS as a method for capturing early manifestations of fearfulness and anxiety in young children. Multimethod assessments incorporating standardized methods for assessing discrete, observable manifestations of anxiety may be beneficial for early identification and clinical intervention efforts

Review of The Oxbridge Evangelist: Motivations, Practices, and Legacy of C. S. Lewis

Review of Michael J. Gehring, The Oxbridge Evangelist: Motivations, Practices, and Legacy of C. S. Lewis (Eugene, Oregon: Cascade Books, 2017). xi + 250 pages. $32.70. ISBN 9781498290067