Secular sea level change in the Russian sector of the Arctic Ocean

Author Posting. © American Geophysical Union, 2004. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 109 (2004): C03042, doi:10.1029/2003JC002007.Sea level is a natural integral indicator of climate variability. It reflects changes in practically all dynamic and thermodynamic processes of terrestrial, oceanic, atmospheric, and cryospheric origin. The use of estimates of sea level rise as an indicator of climate change therefore incurs the difficulty that the inferred sea level change is the net result of many individual effects of environmental forcing. Since some of these effects may offset others, the cause of the sea level response to climate change remains somewhat uncertain. This paper is focused on an attempt to provide first-order answers to two questions, namely, what is the rate of sea level change in the Arctic Ocean, and furthermore, what is the role of each of the individual contributing factors to observed Arctic Ocean sea level change? In seeking answers to these questions we have discovered that during the period 1954–1989 the observed sea level over the Russian sector of the Arctic Ocean is rising at a rate of approximately 0.123 cm yr−1 and that after correction for the process of glacial isostatic adjustment this rate is approximately 0.185 cm yr−1. There are two major causes of this rise. The first is associated with the steric effect of ocean expansion. This effect is responsible for a contribution of approximately 0.064 cm yr−1 to the total rate of rise (35%). The second most important factor is related to the ongoing decrease of sea level atmospheric pressure over the Arctic Ocean, which contributes 0.056 cm yr−1, or approximately 30% of the net positive sea level trend. A third contribution to the sea level increase involves wind action and the increase of cyclonic winds over the Arctic Ocean, which leads to sea level rise at a rate of 0.018 cm yr−1 or approximately 10% of the total. The combined effect of the sea level rise due to an increase of river runoff and the sea level fall due to a negative trend in precipitation minus evaporation over the ocean is close to 0. For the Russian sector of the Arctic Ocean it therefore appears that approximately 25% of the trend of 0.185 cm yr−1, a contribution of 0.048 cm yr−1, may be due to the effect of increasing Arctic Ocean mass.This material is based upon work supported by the National Science Foundation under grant 0136432

Controlling The pH Of Cultures Of Penicillium Notatum Through Its Carbon And Nitrogen Nutrition

A survey of published material reveals relatively little information concerning the nutritional physiology of Penicillium notatum Westl. on synthetic media. Metabolism studies of P. notatum on various media have appeared to be incidental to the more pressing problem of producing penicillin quickly and in quantity. Fleming (1929) originally used a nutrient broth non-synthetic in nature. The Oxford group (Abraham et al., 1941) then adopted a modification of the so-called Czapek-Dox synthetic medium which supplies nitrogen as sodium nitrate and glucose as carbohydrate. Hobby, Meyer, and Chaffee (1942) suggested that brown sugar be substituted for glucose in this nutrient, with resultant higher yields and decreased time for maximum production of penicillin. Apparently a variety of carbon and nitrogen sources have been employed in liquid nutrients (Foster, 1943; Foster, Woodruff and McDaniel, 1943; McKee and Rake, 1942; Kocholaty, 1942; Waksman and Horning, 1943); but specific data have not been offered. At the present time corn steep liquor appears to be an important component of the medium used

Associations between Indoor Air Pollution and Acute Respiratory Infections among Under-Five Children in Afghanistan: Do SES and Sex Matter?

Background: Low-income families often depend on fuels such as wood, coal, and animal dung for cooking. Such solid fuels are highly polluting and are a primary source of indoor air pollutants (IAP). We examined the association between solid fuel use (SFU) and acute respiratory infection (ARI) among under-five children in Afghanistan and the extent to which this association varies by socioeconomic status (SES) and gender. Materials and Methods: This is a cross-sectional study based on de-identified data from Afghanistan’s first standard Demographic and Health Survey (DHS) conducted in 2015. The sample consists of ever-married mothers with under-five children in the household (n = 27,565). We used mixed-effect Poisson regression models with robust error variance accounting for clustering to examine the associations between SFU and ARI among under-five children after adjusting for potential confounders. We also investigated potential effect modification by SES and sex. Additional analyses were conducted using an augmented measure of the exposure to IAP accounting for both SFU and the location of cooking/kitchen (High Exposure, Moderate, and No Exposure). Results: Around 70.2% of households reported SFU, whereas the prevalence of ARI was 17.6%. The prevalence of ARI was higher in children living in households with SFU compared to children living in households with no SFU (adjusted prevalence ratio (aPR) = 1.10; 95% CI: (0.98, 1.23)). We did not observe any effect modification by SES or child sex. When using the augmented measure of exposure incorporating the kitchen’s location, children highly exposed to IAP had a higher prevalence of ARI compared to unexposed children (aPR = 1.17; 95% CI: (1.03, 1.32)). SES modified this association with the strongest associations observed among children from the middle wealth quintile. Conclusion: The findings have significant policy implications and suggest that ARI risk in children may be reduced by ensuring there are clean cookstoves as well as clean fuels and acting on the socio-environmental pathways

Structure of an active volcano associated with a resurgent block inferred from thermal mapping: The Yasur–Yenkahe volcanic complex (Vanuatu)

International audienceSubsurface thermal measurements provide a valuable tool to map hydrothermal-fluid release zones in active volcanic areas. On the Yasur–Yenkahe volcanic complex (Tanna Island, Vanuatu archipelago), fumaroles and hot springs abound, signs of upraising heat fluxes associated to a well-developed hydrothermal activity. Combination of high resolution mapping of ground thermal anomalies with geomorphological analysis allows the characterization of the structural relationships between the active Yasur volcano and the Yenkahe resurgent block.A complex system of heat release and hydrothermal fluid circulation below the Yasur–Yenkahe complex is evidenced. Circulation, though propagating vertically as a whole, is funneled by stratification. Thus, the main thermal fluid released is almost exclusively concentrated along structural limits that break the seals induced by the stratified nature of the ground. Three types of medium/high temperature anomalies have been evidenced: (1) broad hydrothermalized areas linked with planar stratification that favor lateral spreading, (2) linear segments that represent active faults, and (3) arcuate segments related to paleo-crater rims. The limit between the Yasur volcano and the Yenkahe resurgent block is characterized by an active fault system accommodating both the rapid uplift of the Yenkahe block and the overloading induced by the volcano weight. In such a setting, faults converge below the cone of Yasur, which acts as a focus for the faults. Evidence of such structures, sometimes hidden in the landscape but detected by thermal measurements, is critical for risk assessment of flank landslides

Trace Spaces: an Efficient New Technique for State-Space Reduction

State-space reduction techniques, used primarily in model-checkers, all rely on the idea that some actions are independent, hence could be taken in any (respective) order while put in parallel, without changing the semantics. It is thus not necessary to consider all execution paths in the interleaving semantics of a concurrent program, but rather some equivalence classes. The purpose of this paper is to describe a new algorithm to compute such equivalence classes, and a representative per class, which is based on ideas originating in algebraic topology. We introduce a geometric semantics of concurrent languages, where programs are interpreted as directed topological spaces, and study its properties in order to devise an algorithm for computing dihomotopy classes of execution paths. In particular, our algorithm is able to compute a control-flow graph for concurrent programs, possibly containing loops, which is "as reduced as possible" in the sense that it generates traces modulo equivalence. A preliminary implementation was achieved, showing promising results towards efficient methods to analyze concurrent programs, with very promising results compared to partial-order reduction techniques

Roadside Exposure and Inflammation Biomarkers among a Cohort of Traffic Police in Kathmandu, Nepal

Air pollution is a major environmental problem in the Kathmandu Valley. Specifically, roadside and traffic-related air pollution exposure levels were found at very high levels exceeding Nepal air quality standards for daily PM2.5. In an exposure study involving traffic police officers, we collected 78 blood samples in a highly polluted spring season (16 February 2014–4 April 2014) and 63 blood samples in the less polluted summer season (20 July 2014–22 August 2014). Fourteen biomarkers, i.e., C-reactive protein (CRP), serum amyloid A (SAA), intracellular adhesion molecule (ICAM-1), vascular cell adhesion molecule (VCAM-1), interferon gamma (IFN-γ), interleukins (IL1-β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-13), and tumor necrosis factor (TNF-α) were analyzed in collected blood samples using proinflammatory panel 1 kits and vascular injury panel 2 kits. All the inflammatory biomarker levels were higher in the summer season than in the spring season, while particulate levels were higher in the spring season than in the summer season. We did not find significant association between 24-hour average PM2.5 or black carbon (BC) exposure levels with most of analyzed biomarkers for the traffic volunteers working and residing near busy roads in Kathmandu, Nepal, during 2014. Inflammation and vascular injury marker concentrations were generally higher in females, suggesting the important role of gender in inflammation biomarkers. Because of the small sample size of female subjects, further investigation with a larger sample size is required to confirm the role of gender in inflammation biomarkers

The Adaptation Challenges and Strategies of Adolescent Aboriginal Athletes Competing Off Reserve

Within the motivation literature, it has been indicated that athletes respond more effectively to sport’s contextual challenges through effective adaptation skills. Fiske identified five core motives as facilitators of the adaptation process across cultures: belonging, understanding, controlling, self-enhancement, and trusting. Through a cultural sport psychology approach, the adaptation challenges and strategies of Canadian Aboriginal adolescent athletes from one community (Wikwemikong) are described as they traveled off reserve to compete in mainstream sporting events. Concurrently, Fiske’s core motives are considered in relation to youth sport participants from the aforementioned Aboriginal community. Culture sensitive research methods among the Wikwemikong, including community meetings, talking circles (TCs), indigenous coding, and coauthoring, were employed in this article. Data are reflected in three themes: (a) challenges pursuing sport outside of the Aboriginal community in advance of bicultural encounters, (b) challenging bicultural encounters in Canadian mainstream sport contexts, and (c) specific responses to racism and discrimination

Dispelling the myths of online education: learning via the information superhighway

There continues to be a perception that online education is inferior to traditional education. In the U.S. online learning is more developed than in the U.K. This paper provides insights into a U.S. provision and takes a close look at what are perceived as weaknesses of on line learning and argues that these are not necessarily inherent weaknesses of this form of educational delivery. Then, results of two major studies, undertaken in the U.S. are provided comparing the effectiveness of online education to traditional education as perceived by current MBA students and past graduates. Results of these studies suggest that students of MBA modules and MBA graduates perceive the quality and effectiveness of online education to be similar to, if not higher than, the quality and effectiveness of traditional modules and programmes

Proficiency benchmarking in Spanish

The Language Flagship programs were established at the turn of the century with the goal of creating programs that would move language learners to advanced levels of proficiency in a select number of critical languages (Winke & Gass, 2019). Later, the Flagships called for institutions of higher education to create a viable process to assess proficiency learning in high quality, well-established academic language programs. To answer that call, the present study examines outcomes via end of year proficiency testing in Spanish at the first and second levels of Spanish instruction at the United States Air Force Academy using the Adaptive Listening Tests and the Adaptive Reading Tests developed at Brigham Young University. Results indicate differences in gender, years of study of Spanish, and the number of years of Spanish study prior to attending the Academy. Additionally, the results from the present study are compared to Tschirner’s (2016) comprehensive analysis of student outcomes in higher education on ACTFL reading and listening tests. The findings have implications for programs in higher education as well as those in K-12 education