Electronic stress tensor of the hydrogen molecular ion: Comparison between the exact wave function and approximate wave functions using Gaussian basis sets

We investigate the electronic stress tensor of the hydrogen molecular ion for the ground state using the exact wave function and wave functions approximated by gaussian function basis set expansion. The spatial distribution of the largest eigenvalue, corresponding eigenvectors, tension and kinetic energy density are compared. We find that the cc-pV6Z basis set gives the spindle structure very close to the one calculated from the exact wave function. Similarly, energy density at the Lagrange point is very well approximated by the cc-pV5Z or cc-pV6Z basis sets.Comment: 22 pages, 8 figure

The effect of digital signage on shoppers' behavior: the role of the evoked experience

This paper investigates the role of digital signage as experience provider in retail spaces. The findings of a survey-based field experiment demonstrate that digital signage content high on sensory cues evokes affective experience and strengthens customers’ experiential processing route. In contrast, digital signage messages high on “features and benefits” information evoke intellectual experience and strengthen customers’ deliberative processing route. The affective experience is more strongly associated with the attitude towards the ad and the approach behavior towards the advertiser than the intellectual experience. The effect of an ad high on sensory cues on shoppers’ approach to the advertiser is stronger for first-time shoppers, and therefore important in generating loyalty. The findings indicate that the design of brand-related informational cues broadcast over digital in-store monitors affects shoppers’ information processing. The cues evoke sensory and affective experiences and trigger deliberative processes that lead to attitude construction and finally elicit approach behavior towards the advertisers

Volume-based referral for cardiovascular procedures in the United States: a cross-sectional regression analysis

BACKGROUND: We sought to estimate the numbers of patients affected and deaths avoided by adopting the Leapfrog Group's recommended hospital procedure volume minimums for coronary artery bypass graft (CABG) surgery and percutaneous coronary intervention (PCI). In addition to hospital risk-adjusted mortality standards, the Leapfrog Group recommends annual hospital procedure minimums of 450 for CABG and 400 for PCI to reduce procedure-associated mortality. METHODS: We conducted a retrospective analysis of a national hospital discharge database to evaluate in-hospital mortality among patients who underwent PCI (n = 2,500,796) or CABG (n = 1,496,937) between 1998 and 2001. We calculated the number of patients treated at low volume hospitals and simulated the number of deaths potentially averted by moving all patients to high volume hospitals under best-case conditions (i.e., assuming the full volume-associated reduction in mortality and the capacity to move all patients to high volume hospitals with no related harms). RESULTS: Multivariate adjusted odds of in-hospital mortality were higher for patients treated in low volume hospitals compared with high volume hospitals for CABG (OR 1.16, 95% CI 1.10–1.24) and PCI (OR 1.12, 95% CI 1.05–1.20). A policy of hospital volume minimums would have required moving 143,687 patients for CABG and 87,661 patients for PCI from low volume to high volume hospitals annually and prevented an estimated 619 CABG deaths and 109 PCI deaths. Thus, preventing a single death would have required moving 232 CABG patients or 805 PCI patients from low volume to high volume hospitals. CONCLUSION: Recommended hospital CABG and PCI volume minimums would prevent 728 deaths annually in the United States, fewer than previously estimated. It is unclear whether a policy requiring the movement of large numbers of patients to avoid relatively few deaths is feasible or effective

Sediment and nutrient delivery from thermokarst features in the foothills of the North Slope, Alaska : potential impacts on headwater stream ecosystems

Author Posting. © American Geophysical Union, 2008. 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 113 (2008): G02026, doi:10.1029/2007JG000470.Permafrost is a defining characteristic of the Arctic environment. However, climate warming is thawing permafrost in many areas leading to failures in soil structure called thermokarst. An extensive survey of a 600 km2 area in and around the Toolik Lake Natural Research Area (TLNRA) revealed at least 34 thermokarst features, two thirds of which were new since ∼1980 when a high resolution aerial survey of the area was done. Most of these thermokarst features were associated with headwater streams or lakes. We have measured significantly increased sediment and nutrient loading from thermokarst features to streams in two well-studied locations near the TLNRA. One small thermokarst gully that formed in 2003 on the Toolik River in a 0.9 km2 subcatchment delivered more sediment to the river than is normally delivered in 18 years from 132 km2 in the adjacent upper Kuparuk River basin (a long-term monitoring reference site). Ammonium, nitrate, and phosphate concentrations downstream from a thermokarst feature on Imnavait Creek increased significantly compared to upstream reference concentrations and the increased concentrations persisted over the period of sampling (1999–2005). The downstream concentrations were similar to those we have used in a long-term experimental manipulation of the Kuparuk River and that have significantly altered the structure and function of that river. A subsampling of other thermokarst features from the extensive regional survey showed that concentrations of ammonium, nitrate, and phosphate were always higher downstream of the thermokarst features. Our previous research has shown that even minor increases in nutrient loading stimulate primary and secondary production. However, increased sediment loading could interfere with benthic communities and change the responses to increased nutrient delivery. Although the terrestrial area impacted by thermokarsts is limited, the aquatic habitat altered by these failures can be extensive. If warming in the Arctic foothills accelerates thermokarst formation, there may be substantial and wide-spread impacts on arctic stream ecosystems that are currently poorly understood.The results presented in this report are based upon work supported by the U.S. National Science Foundation under grants to the Arctic Hyporheic project (OPP- 0327440) and the Arctic Long-Term Ecological Research Program (DEB- 9810222)

The effects of teachers' homework follow-up practices on students' EFL performance: a randomized-group design

This study analyzed the effects of five types of homework follow-up practices (i.e., checking homework completion; answering questions about homework; checking homework orally; checking homework on the board; and collecting and grading homework) used in class by 26 teachers of English as a Foreign Language (EFL) using a randomized-group design. Once a week, for 6 weeks, the EFL teachers used a particular type of homework follow-up practice they had previously been assigned to. At the end of the 6 weeks students completed an EFL exam as an outcome measure. The results showed that three types of homework follow-up practices (i.e., checking homework orally; checking homework on the board; and collecting and grading homework) had a positive impact on students' performance, thus highlighting the role of EFL teachers in the homework process. The effect of EFL teachers' homework follow-up practices on students' performance was affected by students' prior knowledge, but not by the number of homework follow-up sessions.This research was supported by the Portuguese Foundation for Science and Technology and the Portuguese Ministry of Education and Science through national funds and when applicable co-financed by FEDER under the PT2020 Partnership Agreement (UID/PSI/01662/2013), by the Spanish Ministry of Education and Science (Proyects: EDU2014-57571-P and PSI-2011-23395) and by Council of Economy and Employment of the Government of the Principality of Asturias, Spain (Proyect: FC-15-GRUPIN14-053).info:eu-repo/semantics/publishedVersio

Closing Information Gaps in Kakuma Refugee Camp: A Youth Participatory Action Research Study

This study explores the role of academic and social support on young people’s educational pursuits in Kenya’s Kakuma Refugee Camp. Pairing ethnographic methods with youth participatory action research, we find that support often manifests as abstract, decontextualized encouragement with little grounding in the educational opportunity structure. We argue that this motivational discourse generates information gaps, fueling aspirations that neither prepare youth for understanding, nor navigating the constraints they will encounter. In response, we designed a social media platform orienting Kakuma youth to the opportunity structure, while encouraging them to set realistic goals and plan accordingly. Designing a resource by, for, and with Kakuma youth, we illustrate that refugees have the rights and means to access information on which their everyday well‐being and futures depend. This study illustrates that critical understanding of local and global opportunities can empower, rather than demoralize, young people as they shape their futures in exile.HighlightsEducational support has limited value when decontextualized from opportunity structures.Critical understanding of opportunity constraints can empower, rather than demoralize, youth.Balancing hope and critical awareness is a central challenge in participatory action research, and in settings of forced displacement.Refugee youth advocate for their right to information on which their well‐being and futures depend.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147082/1/ajcp12277_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/147082/2/ajcp12277.pd

Isotopic signals (18O, 2H, 3H) of six major rivers draining the pan-Arctic watershed

Author Posting. © American Geophysical Union, 2012. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Global Biogeochemical Cycles 26 (2012): GB1027, doi:10.1029/2011GB004159.We present the results of a 4-year collaborative sampling effort that measured δ18O, δ2H values and 3H activities in the six largest Arctic rivers (the Ob, Yenisey, Lena, Kolyma, Yukon and Mackenzie). Using consistent sampling and data processing protocols, these isotopic measurements provide the best available δ2H and 3H estimates for freshwater fluxes from the pan-Arctic watershed to the Arctic Ocean and adjacent seas, which complements previous efforts with δ18O and other tracers. Flow-weighted annual δ2H values vary from −113.3‰ to −171.4‰ among rivers. Annual 3H fluxes vary from 0.68 g to 4.12 g among basins. The integration of conventional hydrological and landscape observations with stable water isotope signals, and estimation of areal yield of 3H provide useful insights for understanding water sources, mixing and evaporation losses in these river basins. For example, an inverse correlation between the slope of the δ18O-δ2H relation and wetland extent indicates that wetlands play comparatively important roles affecting evaporation losses in the Yukon and Mackenzie basins. Tritium areal yields (ranging from 0.760 to 1.695 10−6 g/km2 per year) are found to be positively correlated with permafrost coverage within the studied drainage basins. Isotope-discharge relationships demonstrate both linear and nonlinear response patterns, which highlights the complexity of hydrological processes in large Arctic river basins. These isotope observations and their relationship to discharge and landscape features indicate that basin-specific characteristics significantly influence hydrological processes in the pan-Arctic watershed.Funding for this research was provided by the U.S. National Science Foundation (OPP-0229302), the National Science and Engineering Research Council of Canada (Discovery grant to JJG and IRD fellowship to YY), the U.S. Geological Survey and the Water Resources Division in the Department of Indian Affairs and Northern Development, Canada.2012-09-2

Revisiting regulation of potassium homeostasis in Escherichia coli:the connection to phosphate limitation

Two-component signal transduction constitutes the predominant strategy used by bacteria to adapt to fluctuating environments. The KdpD/KdpE system is one of the most widespread, and is crucial for K+ homeostasis. In Escherichia coli, the histidine kinase KdpD senses K+ availability, whereas the response regulator KdpE activates synthesis of the high-affinity K+ uptake system KdpFABC. Here we show that, in the absence of KdpD, kdpFABC expression can be activated via phosphorylation of KdpE by the histidine kinase PhoR. PhoR and its cognate response regulator PhoB comprise a phosphate-responsive two-component system, which senses phosphate limitation indirectly through the phosphate transporter PstCAB and its accessory protein PhoU. In vivo two-hybrid interaction studies based on the bacterial adenylate cyclase reveal pairwise interactions between KdpD, PhoR, and PhoU. Finally, we demonstrate that cross-regulation between the kdpFABC and pstSCAB operons occurs in both directions under simultaneous K+ and phosphate limitation, both in vitro and in vivo. This study for the first time demonstrates direct coupling between intracellular K+ and phosphate homeostasis and provides a mechanism for fine-tuning of the balance between positively and negatively charged ions in the bacterial cell

Inclusive Masculinities in a Working-Class Sixth Form in Northeast England

This research examines the construction of masculinity among a group of working-class boys aged sixteen to nineteen in the northeast of England. Drawing on data collected from a six-week ethnography with boys in a religious (Christian) sixth form college, this study documents how only a small minority of these boys embodied the orthodox archetype of masculinity that has traditionally been associated with working-class youth. Instead, the great majority of participants adopted attitudes and behaviors that can be categorized as a set of inclusive masculinities: They espoused positive attitudes toward homosexuality, engaged in physical tactility and emotional intimacy, and used homosexually themed language without the intent to wound or marginalize other boys. These findings pose a considerable challenge to dominant narratives on working-class masculinities; narratives that must now be reconfigured to account for the proliferation of inclusive masculinities among working-class youth

"Homework Should Be...but We Do Not Live in an Ideal World": Mathematics teachers' perspectives on quality homework and on homework assigned in elementary and middle schools

Existing literature has analyzed homework characteristics associated with academic results. Researchers and educators defend the need to provide quality homework, but there is still much to be learned about the characteristics of quality homework (e.g., purposes, type). Acknowledging that teachers play an important role in designing and assigning homework, this study explored teachers' perspectives regarding: (i) the characteristics of quality homework and (ii) the characteristics of the homework tasks assigned. In the current study, mathematics teachers from elementary and middle schools (N = 78) participated in focus group discussions. To enhance the trustworthiness of the findings, homework tasks assigned by 25% of the participants were analyzed for triangulation of data purposes. Data were analyzed using thematic analysis for elementary and middle school separately. Teachers discussed the various characteristics of quality homework (e.g., short assignments, adjusted to the availability of students) and shared the characteristics of the homework tasks typically assigned, highlighting a few differences (e.g., degree of individualization of homework, purposes) between these two topics. Globally, data on the homework tasks assigned were consistent with teachers' reports about the characteristics of the homework tasks they usually assigned. Findings provide valuable insights for research and practice aimed to promote the quality of homework and consequently students' learning and progress.This study was conducted at Psychology Research Centre, University of Minho, and supported by the Portuguese Foundation for Science and Technology and the Portuguese Ministry of Education and Science through national funds and when applicable co-financed by FEDER under the PT2020 Partnership Agreement (UID/PSI/01662/2013). PR was supported by the research projects EDU2013-44062-P (MINECO) and EDU2017-82984-P (MEIC). TN was supported by a Ph.D. fellowship (SFRH/BD/80405/2011) from the Portuguese Foundation for Science and Technology (FCT)