1,508 research outputs found
A New Generating Function for Calculating the Igusa Local Zeta Function
A new method is devised for calculating the Igusa local zeta function
of a polynomial over a -adic field. This involves a new
kind of generating function that is the projective limit of a family of
generating functions, and contains more data than . This resides in
an algebra whose structure is naturally compatible with operations on the
underlying polynomials, facilitating calculation of local zeta functions. This
new technique is used to expand significantly the set of quadratic polynomials
whose local zeta functions have been calculated explicitly. Local zeta
functions for arbitrary quadratic polynomials over -adic fields with odd
are presented, as well as for polynomials over unramified -adic fields of
the form where is a quadratic form and is a linear form where
and have disjoint variables. For a quadratic form over an arbitrary
-adic field with odd , this new technique makes clear precisely which of
the three candidate poles are actual poles.Comment: 54 page
The âCriticalâ Elements of Illness Management and Recovery: Comparing Methodological Approaches
This study examined three methodological approaches to defining the critical elements of Illness Management and Recovery (IMR), a curriculum-based approach to recovery. Sixty-seven IMR experts rated the criticality of 16 IMR elements on three dimensions: defining, essential, and impactful. Three elements (Recovery Orientation, Goal Setting and Follow-up, and IMR Curriculum) met all criteria for essential and defining and all but the most stringent criteria for impactful. Practitioners should consider competence in these areas as preeminent. The remaining 13 elements met varying criteria for essential and impactful. Findings suggest that criticality is a multifaceted construct, necessitating judgments about model elements across different criticality dimensions
Mesopore etching under supercritical conditions â A shortcut to hierarchically porous silica monoliths
Hierarchically porous silica monoliths are obtained in the two-step Nakanishi process, where formation of a macro microporous silica gel is followed by widening micropores to mesopores through surface etching. The latter step is carried out through hydrothermal treatment of the gel in alkaline solution and necessitates a lengthy solvent exchange of the aqueous pore fluid before the ripened gel can be dried and calcined into a mechanically stable macro mesoporous monolith. We show that using an ethanol water (95.6/4.4, v/v) azeotrope as supercritical fluid for mesopore etching eliminates the solvent exchange, ripening, and drying steps of the classic route and delivers silica monoliths that can withstand fast heating rates for calcination. The proposed shortcut decreases the overall preparation time from ca. one week to ca. one day. Porosity data show that the alkaline conditions for mesopore etching are crucial to obtain crack-free samples with a narrow mesopore size distribution. Physical reconstruction of selected samples by confocal laser scanning microscopy and subsequent morphological analysis confirms that monoliths prepared via the proposed shortcut possess the high homogeneity of silica skeleton and macropore space that is desirable in adsorbents for flow-through applications
Early exposure of bay scallops (Argopecten irradians) to high CO2 causes a decrease in larval shell growth
© The Author(s), 2013. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS ONE 8 (2013): e61065, doi:10.1371/journal.pone.0061065.Ocean acidification, characterized by elevated pCO2 and the associated decreases in seawater pH and calcium carbonate saturation state (Ω), has a variable impact on the growth and survival of marine invertebrates. Larval stages are thought to be particularly vulnerable to environmental stressors, and negative impacts of ocean acidification have been seen on fertilization as well as on embryonic, larval, and juvenile development and growth of bivalve molluscs. We investigated the effects of high CO2 exposure (resulting in pH = 7.39, Ωar = 0.74) on the larvae of the bay scallop Argopecten irradians from 12 h to 7 d old, including a switch from high CO2 to ambient CO2 conditions (pH = 7.93, Ωar = 2.26) after 3 d, to assess the possibility of persistent effects of early exposure. The survival of larvae in the high CO2 treatment was consistently lower than the survival of larvae in ambient conditions, and was already significantly lower at 1 d. Likewise, the shell length of larvae in the high CO2 treatment was significantly smaller than larvae in the ambient conditions throughout the experiment and by 7 d, was reduced by 11.5%. This study also demonstrates that the size effects of short-term exposure to high CO2 are still detectable after 7 d of larval development; the shells of larvae exposed to high CO2 for the first 3 d of development and subsequently exposed to ambient CO2 were not significantly different in size at 3 and 7 d than the shells of larvae exposed to high CO2 throughout the experiment.This work was funded by a Woods Hole Oceanographic Institution Interdisciplinary Award to Mullineaux & McCorkle; and awards to Mullineaux & White, to McCorkle, and to Cohen & McCorkle through NOAA (National Oceanic and Admosphereic Administration) Sea Grant #NA10OAR4170083. White was funded through a National Defense Science and Engineering Graduate Fellowship through the American Society for Engineering Education
âI felt really respected and I know she felt respected tooâ: Using Youth-Adult Partnerships to Promote Positive Youth Development in 4-H Youth
Youth-adult relationships exist on a continuum from adult-led to youth-led collaborations. However, research suggests that quality youth-adult partnerships, which fall in the middle of this continuum, directly contribute to positive youth development. Given this, the current study evaluated the impact of a 4-H Youth Development program, using youth-adult partnerships and a teens as teachers program model, on positive youth development outcomes of participating youth. Qualitative data were collected from 29 youth to evaluate the 4-H Food Smart Families program presented by Washington State University Youth Advocates for Health (YA4-H!). Data analysis identified themes related to the benefits and challenges of the youth-adult partnership and skills gained from being a teen teacher. When looking at results from a positive youth development perspective, it is evident the youth who participated in youth-adult partnerships and as teen teachers experienced beneficial outcomes. Qualitative codes clearly aligned with 4-H Essential Elements of belonging, mastery, independence, and generosity, indicating positive youth development had occurred despite realworld implementation challenges. Based on our experience and lessons learned, we conclude with suggestions for successful implementation of a youth-adult partnership
Outdoor atmospheric microplastics within the Humber region (United Kingdom): Quantification and chemical characterisation of deposited particles present
Atmospheric microplastics (MPs) have been consistently captured within air samples on a global scale. Locations with high human activity are reported to have high MP levels. An urban sampling site in the Humber region (U.K.) has been sampled over a 13-month period, providing a seasonal variation profile of MP levels, size, shape, and polymer types that humans are exposed to. Mean MP levels, measured using passive fallout into a container, were 3055 ± 5072 MP mâ2 dayâ1 (1164 median). An increase in levels with a decrease in MP size was observed, consisting of mainly film-shaped MPs (67%) that were polyethylene (31%) and nylon (28%) polymer types. No relationship between rainfall and MP fallout levels was observed. In parallel, MPs within five urban-ised locations relevant to human exposure were characterised over a 2-week period. An overall MP mean (and standard deviation) of 1500 ± 1279 was observed (1012 median), from which petroleum resin accounted for 32% of MP polymer type, with a higher prevalence within industrial and roadside zones. These comprised mainly fragment (52%) and film (42%) shapes, and the MPs levels increased with decreasing particle size. The results provide novel information on characterising polymer levels and types, and can inform cellular toxicity studies, investigating the consequences of human MP exposure
A systematic scoping review evaluating sugar-sweetened beverage taxation from a systems perspective
An interdisciplinary assessment of climate engineering strategies
Author Posting. © Ecological Society of America, 2014. This article is posted here by permission of Ecological Society of America for personal use, not for redistribution. The definitive version was published in Frontiers in Ecology and the Environment 12 (2014): 280â287, doi:10.1890/130030.Mitigating further anthropogenic changes to the global climate will require reducing greenhouse-gas emissions (âabatementâ), or else removing carbon dioxide from the atmosphere and/or diminishing solar input (âclimate engineeringâ). Here, we develop and apply criteria to measure technical, economic, ecological, institutional, and ethical dimensions of, and public acceptance for, climate engineering strategies; provide a relative rating for each dimension; and offer a new interdisciplinary framework for comparing abatement and climate engineering options. While abatement remains the most desirable policy, certain climate engineering strategies, including forest and soil management for carbon sequestration, merit broad-scale application. Other proposed strategies, such as biochar production and geological carbon capture and storage, are rated somewhat lower, but deserve further research and development. Iron fertilization of the oceans and solar radiation management, although cost-effective, received the lowest ratings on most criteria. We conclude that although abatement should remain the central climate-change response, some low-risk, cost-effective climate engineering approaches should be applied as complements. The framework presented here aims to guide and prioritize further research and analysis, leading to improvements in climate engineering strategies.NSF grant
#1103575 supported KRMM
Outdoor Microplastic Analysis Using Inlet Filters from an NOx Regulatory Air Quality Monitoring Device
Atmospheric microplastics (MPs) are a ubiquitous environmental contaminant of emerging concern. Sampling methods provide information relating to surface area concentration and MP characteristics, without direct comparison with routinely measured standard air quality parameters. This study analysed 6 active air samples generated by a local authority as part of their routine air quality monitoring activities. Continuous sampling totalled 10 months, within the city centre of Kingston-upon-Hull. By using ÎŒFTIR analysis, levels of total particles detected using the NOx inlet filters ranged from 5139 ± 2843 particles mâ2 dayâ1, comprising 1029 ± 594 MPs mâ2 dayâ1. The controls displayed a mean level of 2.00 ± 3.49 MPs. The polymers nylon (32%) and polypropylene, PP (22%) were the most abundant. Small fragments of 47.42 ± 48.57 ÎŒm (length) and 21.75 ± 13.62 ÎŒm (width) were most common. An increase in MP levels during April 2020 coincided with an increase in PM10 levels. This study used robust procedures to measure MPs in the air by exploiting existing air quality monitoring equipment. Knowing the levels, types, and characteristics of MPs can inform toxicity studies to provide more environmentally relevant exposures, which is urgent now that MPs have been reported in human lung tissu
Palliative radiation therapy (RT) for prostate cancer patients with bone metastases at diagnosis: A hospitalâbased analysis of patterns of care, RT fractionation scheme, and overall survival
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