4,570 research outputs found

    Laboratory Spectra of CO2 Vibrational Modes in Planetary Ice Analogs

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    Laboratory spectra have shown that CO2 is a powerful diagnostic tool for analyzing infrared data from remote observations, as it has been detected on icy moons in the outer Solar System as well as dust grain surfaces in the interstellar medium (ISM). IR absorption band profiles of CO2 within ice mixtures containing H2O and CH3OH change with respect to temperature and mixture ratios. In this particular study, the CO2 asymmetric stretching mode near 4.3 m (2350 cm (exp-1)), overtone mode near 1.97 m (5080 cm (exp-1)), and the combination bands near 2.7 m (3700 cm (exp-1)), 2.8 m (3600 cm (exp-1)), and 2.02 m (4960 cm (exp -1)), are systematically observed in different mixtures with H2O and CH3OH in temperature ranges from 15K to 150 K. Additionally, some high-temperature deposits (T greater than 50 K) of H2O, CH3OH, and CO2 ice mixtures were performed. These data may then be used to interpret infrared observational data obtained from icy surfaces in the outer Solar System and beyond

    Examining the Children’s Defense Fund Freedom Schools Model on Middle School Students’ Reading Achievement

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    In effort to curb summer learning loss, the Children’s Defense Fund Freedom Schools program identifies as a six-week summer literacy program for students in grades K-12. This study explored the impact of the Freedom School program on 128 middle school students’ reading achievement using Johns (2005) Basic Reading Inventory. Findings support the program’s effectiveness in increasing students’ reading outcomes, as demonstrated in the existent literature, but unlike other studies, data provided for both independent and instructional levels across three fluency indicators. In recognition of heightened state of summer learning loss for students with lack of access to quality enrichment summer programming, the study reveals the program\u27s positive impact and academic outcomes for student participants. Implications for future research that examine longitudinal impacts of the program and the value in utilizing multicultural literature are provided

    A New View of Ridge Segmentation and Near-Axis Volcanism at the East Pacific Rise, 8˚–12˚N, from EM300 Multibeam Bathymetry

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    New, high-resolution bathymetry for the East Pacific Rise between 8˚N and 12˚N was collected over a6 km wide swath centered on the ridge axis using the 30 kHz Simrad EM300 multibeam system. Thecoverage area corresponds latitudinally to the designated Ridge2000 Integrated Studies Site (ISS) for fastspreading ridges. The EM300 data, gridded at 30 m latitude by 50 m longitude, represent a greater than 4Ximprovement in horizontal resolution over previously available multibeam data and a 2X improvement indepth resolution. The new bathymetry was used to update the locations and hierarchy of ridge offsets forthis area. Among the many applications for this data, it enables us to tabulate volcanoes half the size thatcould be previously detected. The distribution of near-axis volcanic cones \u3e25 m high suggests that thispopulation of small, near-axis cones results from low effusion rate eruptions of the ridge axis

    Basaltic Lava Domes, Lava Lakes, and Volcanic Segmentation on the Southern East Pacific Rise

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    Meter-scale DSL-120 sonar mapping and coregistered Argo II photographic observations reveal changes in eruptive style that closely follow the third-order structural segmentation of the ridge axis on the southern East Pacific Rise, 17o11\u27-18o37\u27S. Near segment ends we observe abundant basaltic lava domes which average 20 rn in height and 200 rn in basal diameter and have pillow lava as the dominant lava morphology. The ubiquity of pillow lava suggests low effusion rate eruptions. The abundance of lava domes suggests that the fissure eruptions were of sufficient duration to focus and produce a line of volcanic edifices. Near segment centers we observe fewer but larger lava domes, voluminous drained and collapsed lava lakes, and smooth lobate and sheet lava flows with very little pillow lava. The abundance of sheet flows suggests that high effusion rate eruptions are common. Fewer lava domes and large lava lakes suggest that fissure eruptions do not focus to point sources. This pattern was observed on eight third-order ridge segments suggesting that a fundamental volcanic segmentation of the ridge occurs on this scale. The third-order segment boundaries also correlate with local maxima in the seismicaxial magmac hamber reflector depth throughout the study area and decreased across-axis width of the region of seismic layer 2A thickening along the one segment where sufficient cross-axis seismic lines exist. The geochemically defined magmatic segment boundaries in the study area match the locations of our volcanic segment boundaries, although rocks ampling density is not adequate to constrain the variation across all the third-order volcanic segments that we identify. These observations suggest that variation in the processes of crustal accretion along axis occurs at a length scale of tens of kilometers on superfast spreading (\u3e 140 km/Myr full rate) mid-ocean ridges

    Evaluating lethal toxicant doses for the largest individuals of an invasive vertebrate predator with indeterminate growth

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    The brown treesnake (Boiga irregularis) was accidentally introduced to Guam and caused severe ecological and economic damages. Acetaminophen is an effective, low-risk oral toxicant for invasive brown treesnakes, and an automated aerial delivery system (ADS) has been developed for landscape-scale toxic bait distribution. A fixed dose of 80 mg of acetaminophen within a tablet inserted into a dead neonatal mouse (DNM) was lethal for all brown treesnakes in previous trials; however, these trials did not include very large individuals which are difficult to acquire for testing. Because most reptiles continue to grow throughout their lifespan, a small number reach much greater than average body sizes. Here, we tested effectiveness of 80 mg acetaminophen DNM baits for unusually large brown treesnakes as they became available. Our results confirmed that an 80 mg dose is lethal for the vast majority of snakes on Guam, but efficacy starts to diminish around 200 g of body mass. We also tested an alternative mouse bait configuration with 160 mg of acetaminophen that could be incorporated into the ADS to improve control of unusually large snakes. The 160 mg dose is expected to be effective for nearly all female snakes; males grow much larger and additional methods will be needed for extraordinarily large individuals. We describe a full dose-response curve for brown treesnakes to acetaminophen tablets and estimate the LD90 at 299 mg/kg and the LD99 at 578 mg/kg. To our knowledge, this is the first published dose-response curve for an invasive vertebrate with indeterminate growth

    Crustal Fissuring on the Crest of the Southern East Pacific Rise at 17˚15\u27-40\u27S

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    Fissure densities and widths have been mapped along the axial zone of the superfast spreading southern East Pacific Rise (EPR) at 17_150–400S with the near-bottom DSL-120 and Argo II imaging systems. We observe that the youngest lava flows (on a relative age scale) are sparsely fissured and that there is a cumulative increase in fissure abundance with time that produces a strong positive correlation between fissure density and relative age of lava flows. Average fissure widths were used to estimate fissure depths. In the 17_150–400S area, calculated fissure depths are estimated to extend below the seismic layer 2A/2B boundary, and fissures are widest/deepest where lava flows are youngest. We interpret these wide fissures in relatively young flows to be eruptive fissures. Relatively young lava flows combined with high average fissure widths south of 17_250S suggest that there may have been recent dike propagation along the ridge crest in this area. In comparison to the northern EPR at 9_–10_N the density of fissuring on the southern EPR is significantly higher, due in part to the higher occurrence of relatively older, more areally restricted pillow lava flows

    “Mental health day” sickness absence amongst nurses and midwives: Workplace, workforce, psychosocial and health characteristics

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    Aim To examine the workforce, workplace, psychosocial and health characteristics of nurses and midwives in relation to their reported use of sickness absence described as ‘mental health days’. Background The occupational stress associated with the nursing profession is increasingly recognized and nurse/midwifery absenteeism is a significant global problem. Taking a ‘mental health day’ as sickness absence is a common phenomenon in Australian health care. No previous studies have empirically explored the characteristics of nurses and midwives using such sickness absence. Design Online cross-sectional survey. Methods Survey comprising validated tools and questions on workplace and health characteristics was distributed to nurses and midwives in New South Wales, Australia, between May 2014 - February 2015. Sample characteristics were reported using descriptive statistics. Factors independently predictive of ‘mental health day’ reportage were determined using logistic regression. Results Fifty-four percentage of the n = 5041 nurse and midwife respondents took ‘mental health days’. Those affected were significantly more likely to be at younger ages, working shifts with less time sitting at work; to report workplace abuse and plans to leave; having been admitted to hospital in previous 12 months; to be current smokers; to report mental health problems, accomplishing less due to emotional problems and current psychotropic medication use. Conclusion Specific characteristics of nurses and midwives who report taking ‘mental health day’ sickness absence offer healthcare administrators and managers opportunities for early identification and intervention with workplace measures and support frameworks to promote well-being, health promotion and safety

    Eyes Save Lives Water Safety Program for Parents and Caregivers: Program Design and Pilot Evaluation from Southern California

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    Despite expert consensus and evidence-based preventative strategies against drowning, limited formal study exists on translating recommendations into practical and effective interventions. This paper describes the design of an education-based drowning prevention intervention and reports results from a pilot evaluation of the program’s effect on self-reported water-safe behaviors, attitudes, self-efficacy, and knowledge. Parents and caregivers attending children’s swim lessons in July and August 2018 participated in a brief water-safety education program. A pre-post-test design evaluated Theory of Planned Behavior indicators to assess for changes. We found significant increases in scores related to water safety knowledge, attitudes on maintaining arms reach distance to children in the pool, recognizing a child in distress, and self-efficacy of responding to water emergencies involving a child between pre- and post-program. Swim lessons provided a captive audience receptive to drowning prevention information. Due to minimal costs, the program could easily be replicated and delivered to a variety of parent groups

    Preventing Isolated Perioperative Reintubation: Who is at highest risk?

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    Objectives: 1. We aim to characterize IPR nationally through a retrospective review of the National Surgical Quality Improvement Program participant user file (NSQIP PUF). 2.Identify risk factors for IPR including analysis of procedure type and preoperative characteristics.https://jdc.jefferson.edu/patientsafetyposters/1041/thumbnail.jp
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