Efficient measurement of an optical orbital-angular-momentum spectrum comprising more than 50 states

A light beam may be separated into its orbital-angular momentum (OAM) components by a geometric optical transformation that converts each OAM component into a plane wave with a transverse phase gradient. Subsequent focusing produces a spot the lateral position of which is proportional to the input OAM state (Lavery et al 2012 Opt. Express 20 3). In this paper, we improve this approach, extending the measurement bandwidth to >50 OAM states and showing a simultaneous measurement of the radial coordinate

Using Online Carbon Calculators for Participation in Local Climate Initiatives

Part 4: Case StudiesInternational audienceThe paper reviews various eco-feedback systems including carbon calculators and discusses how different disciplinary approaches conceptualise and explain anticipated impacts of these systems. The European collaborative research project e2democracy investigates how citizen participation combined with long-term CO2 monitoring and feedback can contribute to achieve local climate targets. Empirical results from local climate initiatives in Austria, Germany and Spain show positive effects in terms of learning about CO2 impacts, increased awareness, enhanced efforts and guidance as well as individual empowerment leading to slightly reduced CO2 emissions. The findings highlight that a combined approach integrating eco-feedback and (e )participation is promising to foster sustainability

Being a ‘good’ mother: Immigrant mothers of disabled children

In South Korea, disability and immigration are hidden and invisible phenomena. This article examines how immigrant mothers experience the intersection of immigrant status and mothering a disabled child. Through semi-structured interviews with 16 immigrant mothers, this study found that the values of Confucian familism regarding motherhood and gender roles influenced how these immigrant mothers behaved. The study also found that immigrant mothers faced multiple forms of stigma and discrimination as a result of negative socio-cultural views of disability and immigration. Therefore, the article suggests a need for inter-professional, anti-oppression work strategies to support immigrant mothers of disabled children, along with education for social workers about these issues

Toward the improvement of total nitrogen deposition budgets in the United States

Frameworks for limiting ecosystem exposure to excess nutrients and acidity require accurate and complete deposition budgets of reactive nitrogen (Nr). While much progress has been made in developing total Nr deposition budgets for the U.S., current budgets remain limited by key data and knowledge gaps. Analysis of National Atmospheric Deposition Program Total Deposition (NADP/TDep) data illustrates several aspects of current Nr deposition that motivate additional research. Averaged across the continental U.S., dry deposition contributes slightly more (55%) to total deposition than wet deposition and is the dominant process (>90%) over broad areas of the Southwest and other arid regions of the West. Lack of dry deposition measurements imposes a reliance on models, resulting in a much higher degree of uncertainty relative to wet deposition which is routinely measured. As nitrogen oxide (NOx) emissions continue to decline, reduced forms of inorganic nitrogen (NHx = NH3 + NH4 +) now contribute >50% of total Nr deposition over large areas of the U.S. Expanded monitoring and additional process-level research are needed to better understand NHx deposition, its contribution to total Nr deposition budgets, and the processes by which reduced N deposits to ecosystems. Urban and suburban areas are hotspots where routine monitoring of oxidized and reduced Nr deposition is needed. Finally, deposition budgets have incomplete information about the speciation of atmospheric nitrogen; monitoring networks do not capture important forms of Nr such as organic nitrogen. Building on these themes, we detail the state of the science of Nr deposition budgets in the U.S. and highlight research priorities to improve deposition budgets in terms of monitoring and flux measurements, leaf- to regional-scale modeling, source apportionment, and characterization of deposition trends and patterns.</p