1,378 research outputs found

    Intraseasonal Variations in Tropical Energy Balance: Relevance to Climate Sensitivity?

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    Intraseasonal variability of deep convection represents a fundamental mode of organization for tropical convection. While most studies of intraseasonal oscillations (ISOs) have focused on the spatial propagation and dynamics of convectively coupled circulations, here we examine the projection of ISOs on the tropically-averaged heat and moisture budget. One unresolved question concerns the degree to which observable variations in the "fast" processes (e.g. convection, radiative / turbulent fluxes) can inform our understanding of feedback mechanisms operable in the context of climate change. Our analysis use daily data from satellite observations, the Modern Era analysis for Research and Applications (MERRA), and other model integrations to address these questions: (i) How are tropospheric temperature variations related to that tropical deep convection and the associated ice cloud fractional amount (ICF), ice water path (IWP), and properties of warmer liquid clouds? (ii) What role does moisture transport play vis-a-vis ocean latent heat flux in enabling the evolution of deep convection to mediate PBL - free atmospheric temperature equilibration? (iii) What affect do convectively generated upper-tropospheric clouds have on the TOA radiation budget? Our methodology is similar to that of Spencer et al., (2007 GRL ) whereby a composite time series of various quantities over 60+ ISO events is built using tropical mean tropospheric temperature signal as a reference to which the variables are related at various lag times (from -30 to +30 days). The area of interest encompasses the global oceans between 20oN/S. The increase of convective precipitation cannot be sustained by evaporation within the domain, implying strong moisture transports into the tropical ocean area. The decrease in net TOA radiation that develops after the peak in deep convective rainfall, is part of the response that constitutes a "discharge" / "recharge" mechanism that facilitates tropical heat balance maintenance on these time scales. However, water vapor and hydrologic scaling relationships for this mode of variability cast doubt on the utility of ISO variations as proxies for climate sensitivity response to external radiatively forced (e.g. greenhouse gas-induced) climate change

    Middle school student motivational experiences in mathematics: a narrative inquiry

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    2013 Spring.Includes bibliographical references.Among middle school students there is thought to be a lack of motivation toward academic achievement in math. Ames expressed this thought in 1990 when mentioning this as one of the biggest problems in education. Motivation to learn and grow through mathematic understanding gives students' purpose. Due to this thought, the focus of the study was to use a narrative inquiry experience-centered approach to gain insight into five middle school students' motivational experiences in mathematics at the end of eighth grade. Each student was interviewed over the course of three different sessions, taking place over a three week span of time. These interviews were conducted during their normal school day at a time deemed by the school as not academically hindering (i.e., a study hall or open block). To help with analysis, interview sessions were audio recorded and transcribed into a basic word processor. Nvivo software was then used to create common themes (or nodes) and connect them to common reference points within each student's interview dialogue. Some themes like intrinsic and extrinsic motivation were created prior to analysis and looked for specifically, while other themes were created after being mentioned by multiple students or in multiple interviews. These added themes were noticeably of value to the participants when speaking of their motivational experiences. Data collection and analysis concluded that personal motivators, both intrinsic and extrinsic, were mentioned by all students over the course of their three interview sessions. Student's desire for accomplishment, esteem, and support were all revealed as common motivators. Interview responses reinforced the view that motivation is supported through small, challenging but achievable goals. Students expressed not wanting simple math problems, they wanted to feel challenged. Therefore, benefits for students may be found if teachers are able to balance mathematics challenges with supporting student's current abilities and academic competence. What was also concluded is a definite relationship between the various levels of Maslow's Hierarchy of Needs being satisfied and an increase in student motivation. Recommendations for research include looking further into whether students are motivated to satisfy their needs, as Maslow suggests, or rather if the act of feeling calm over a need being met creates further motivation toward academic achievement. Future research into this concept would help formulate true connections between satisfied needs and motivational desire

    The African Political Business Cycle: Varieties of Experience

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    We seek to understand both the incidence and the impact of the African political business cycle in the light of a literature which has argued that, with major extensions of democracy since the 1990s, the cycle has both become more intense and has made African political systems more fragile. With the help of country-case studies, we argue, first, that the African political business cycle is not homogeneous, and occurs relatively infrequently in so-called ‘dominant-party systems’ where a pre-election stimulus confers little political advantage. Secondly, we show that, in those countries where a political cycle does occur, it does not necessarily cause institutional damage. Whether it does or not depends not so much on whether there is an electoral cycle as on whether this cycle calms or exacerbates fears of an unjust allocation of resources. In other words, the composition of the pre-election stimulus, in terms of its allocation between different categories of voter, is as important as its size

    Cryo-Vacuum Testing of the Integrated Science Instrument Module for the James Webb Space Telescope

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    With delivery of the science instruments for the James Webb Space Telescope (JWST) to Goddard Space Flight Center (GSFC) expected in 2012, current plans call for the first cryo-vacuum test of the Integrated Science Instrument Module (ISIM) to be carried out at GSFC in early 2013. Plans are well underway for conducting this ambitious test, which will perform critical verifications of a number of optical, thermal, and operational requirements of the IS 1M hardware, at its deep cryogenic operating temperature. We describe here the facilities, goals, methods, and timeline for this important Integration & Test milestone in the JWST program

    Construction Mortgage Financing in Ohio

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    This article consists of a review and analysis of the Yarborough decision and the open-end mortgage statute and an assessment of their probable impact upon current construction loan lending procedures. In addition, the authors offer various observations regarding the form in which disbursing agreements and construction mortgage deeds should be drafted. The structure of the article may be briefly described as follows: First, attention will be given to the three methods by which a mortgagee can preserve the priority of its mortgage lien over liens of mechanics men which attach to the mortgaged premises after the recording of the mortgage but before any disbursements are made thereunder. Special consideration will be given to the manner in which the Yarborough decision affects each method. Second, the writers will discuss the manner in which openend mortgages relate to: (1) non-statutory construction mortgages and (2) mechanics\u27 and other types of liens which attach to the mortgaged premises after the recording of an open-end mortgage but before any optional disbursements are made thereunder. In this connection, the use of open-end mortgages to secure construction loans will be considered. Third, the advisability of drafting an open-end mortgage which incorporates the provisions of § 1311.14 of the Mechanic\u27s Lien Statute will be examined. Fourth, the authors will discuss a proposed method by which a mortgagee can reasonably assure that its mortgage lien will take priority over any vendees\u27 liens which exist on the date of the recording of the mortgag

    Macroeconomic Fluctuations, Inequality, and Human Development

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    This paper examines the two-way relationship between inequality and economic fluctuations, and the implications for human development. For years, the dominant paradigm in macroeconomics, which assumed that income distribution did not matter, at least for macroeconomic behavior, ignored inequality--both its role in causing crises and the effect of fluctuations in general, and crises in particular, on inequality. But the most recent financial crisis has shown the errors in this thinking, and these views are finally beginning to be questioned. Economists who had looked at the average equity of a homeowner--ignoring the distribution--felt comfortable that the economy could easily withstand a large fall in housing prices. When such a fall occurred, however, it had disastrous effects, because a large fraction of homeowners owed more on their homes than the value of the home, leading to waves of foreclosure and economic stress. Policy-makers and economists alike have begun to take note: inequality can contribute to volatility and the creation of crises, and volatility can contribute to inequality. Here, we explore the variety of channels through which inequality affects fluctuations and fluctuations affect inequality, and explore how some of the changes in our economy may have contributed to increased inequality and volatility both directly and indirectly. After describing the two-way relationship, the paper discusses hysteresis--the fact that the consequences of an economic downturn can be long-lived. Then, it examines how policy can either mitigate or exacerbate the inequality consequences of economic downturns, and shows how well-intentioned policies can sometimes be counterproductive. Finally, it links these issues to human development, especially in developing countries

    Facilitating Adolescent Well-Being: A Review of the Challenges and Opportunities and the Beneficial Roles of Parents, Schools, Neighborhoods, and Policymakers

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    Adolescents face exceptional challenges and opportunities that may have a lifelong impact on their consumption and personal and societal well-being. Parents, community members (schools and neighborhoods), and policymakers play major roles in shaping adolescents and influencing their engagement in consumption behaviors that are either developmentally problematic (e.g., drug use and unhealthy eating) or developmentally constructive (e.g., academic pursuits and extracurricular activities). In this article, we discuss two main topics: (a) the challenges and opportunities that characterize adolescence, based primarily on research in epidemiology and neuroscience, and (b) the ways that parents, community members, and policymakers can facilitate positive adolescent development, based on research from many disciplines including marketing, psychology, sociology, communications, public health, and education. Our goal is to summarize the latest scientific findings that can be used by various stakeholders to help adolescents navigate this turbulent period and become well-adjusted, thriving adults

    Trauma ICU Prevalence Project: the diversity of surgical critical care.

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    Background:Surgical critical care is crucial to the care of trauma and surgical patients. This study was designed to provide a contemporary assessment of patient types, injuries, and conditions in intensive care units (ICU) caring for trauma patients. Methods:This was a multicenter prevalence study of the American Association for the Surgery of Trauma; data were collected on all patients present in participating centers' trauma ICU (TICU) on November 2, 2017 and April 10, 2018. Results:Forty-nine centers submitted data on 1416 patients. Median age was 58 years (IQR 41-70). Patient types included trauma (n=665, 46.9%), non-trauma surgical (n=536, 37.8%), medical (n=204, 14.4% overall), or unspecified (n=11). Surgical intensivists managed 73.1% of patients. Of ICU-specific diagnoses, 57% were pulmonary related. Multiple high-intensity diagnoses were represented (septic shock, 10.2%; multiple organ failure, 5.58%; adult respiratory distress syndrome, 4.38%). Hemorrhagic shock was seen in 11.6% of trauma patients and 6.55% of all patients. The most common traumatic injuries were rib fractures (41.6%), brain (38.8%), hemothorax/pneumothorax (30.8%), and facial fractures (23.7%). Forty-four percent were on mechanical ventilation, and 17.6% had a tracheostomy. One-third (33%) had an infection, and over half (54.3%) were on antibiotics. Operations were performed in 70.2%, with 23.7% having abdominal surgery. At 30 days, 5.4% were still in the ICU. Median ICU length of stay was 9 days (IQR 4-20). 30-day mortality was 11.2%. Conclusions:Patient acuity in TICUs in the USA is very high, as is the breadth of pathology and the interventions provided. Non-trauma patients constitute a significant proportion of TICU care. Further assessment of the global predictors of outcome is needed to inform the education, research, clinical practice, and staffing of surgical critical care providers. Level of evidence:IV, prospective observational study

    Gulls as Sources of Environmental Contamination by Colistin-resistant Bacteria

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    In 2015, the mcr-1 gene was discovered in Escherichia coli in domestic swine in China that conferred resistance to colistin, an antibiotic of last resort used in treating multi-drug resistant bacterial infections in humans. Since then, mcr-1 was found in other human and animal populations, including wild gulls. Because gulls could disseminate the mcr-1 gene, we conducted an experiment to assess whether gulls are readily colonized with mcr-1 positive E. coli, their shedding patterns, transmission among conspecifics, and environmental deposition. Shedding of mcr-1 E. coli by small gull flocks followed a lognormal curve and gulls shed one strain \u3e101 log10 CFU/g in their feces for 16.4 days, which persisted in the environment for 29.3 days. Because gulls are mobile and can shed antimicrobial-resistant bacteria for extended periods, gulls may facilitate transmission of mcr-1 positive E. coli to humans and livestock through fecal contamination of water, public areas and agricultural operations
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