Relative effects on stratospheric ozone of halogenated methanes and ethanes of social and industrial interest

Four atmospheric modeling groups have calculated relative effects of several halocarbons (chlorofluorocarbons (CFC's)-11, 12, 113, 114, and 115; hydrochlorofluorocarbons (HCFC's) 22, 123, 124, 141b, and 142b; hydrofluorocarbons (HFC's) 125, 134a, 143a, and 152a, carbon tetrachloride; and methyl chloroform) on stratospheric ozone. Effects on stratospheric ozone were calculated for each compound and normalized relative to the effect of CFC-11. These models include the representations for homogeneous physical and chemical processes in the middle atmosphere but do no account for either heterogeneous chemistry or polar dynamics which are important in the spring time loss of ozone over Antarctica. Relative calculated effects using a range of models compare reasonably well. Within the limits of the uncertainties of these model results, compounds now under consideration as functional replacements for fully halogenated compounds have modeled stratospheric ozone reductions of 10 percent or less of that of CFC-11. Sensitivity analyses examined the sensitivity of relative calculated effects to levels of other trace gases, assumed transport in the models, and latitudinal and seasonal local dependencies. Relative effects on polar ozone are discussed in the context of evolving information on the special processes affecting ozone, especially during polar winter-springtime. Lastly, the time dependency of relative effects were calculated

An assessment of climate change and health vulnerability and adaptation in dominica

A climate change and health vulnerability and adaptation assessment was conducted in Dominica, a Caribbean small island developing state located in the Lesser Antilles. The assessment revealed that the country’s population is already experiencing many impacts on health and health systems from climate variability and change. Infectious diseases as well as food and waterborne diseases pose continued threats as climate change may exacerbate the related health risks. Threats to food security were also identified, with particular concern for food production systems. The findings of the assessment included near-term and long-term adaptation options that can inform actions of health sector decision-makers in addressing health vulnerabilities and building resilience to climate change. Key challenges include the need for enhanced financial and human resources to build awareness of key health risks and increase adaptive capacity. Other small island developing states interested in pursuing a vulnerability and adaptation assessment may find this assessment approach, key findings, analysis, and lessons learned usefulThis research was funded by Health Canad

Nanoparticle Hybrid Composites by RF Plasma Spray Deposition

A method of fabricating a composite material includes utilizing a radio frequency plasma process to form a plasma plume comprising nanoparticles. The nanoparticles may comprise boron nitride nanoparticles, silicon carbide nanoparticles, beryllium oxide nanoparticles, or carbon nanoparticles. The nanoparticles may comprise nanotubes or other particles depending on the requirements of a particular application. The nanoparticles are deposited on a substrate by directing a plasma plume towards the substrate. The nanoparticles are formed in the plasma plume immediately prior to being deposited on the substrate. The nanoparticles may form a mechanical bond with the fibers in addition to a chemical bond in the absence of a catalyst. The substrate may comprise a fiber fabric that may optionally be coated with a thin layer of metal. Alternatively, the substrate may comprise a solid material such as a metal sheet or plate

Satellite-based prediction of pCO2 in coastal waters of the eastern North Pacific

Continental margin carbon cycling is complex, highly variable over a range of space and time scales, and forced by multiple physical and biogeochemical drivers. Predictions of globally significant air–sea CO2 fluxes in these regions have been extrapolated based on very sparse data sets. We present here a method for predicting coastal surface-water pCO2 from remote-sensing data, based on self organizing maps (SOMs) and a nonlinear semi-empirical model of surface water carbonate chemistry. The model used simple empirical relationships between carbonate chemistry (total dissolved carbon dioxide (TCO2) and alkalinity (TAlk)) and satellite data (sea surface temperature (SST) and chlorophyll (Chl)). Surface-water CO2 partial pressure (pCO2) was calculated from the empirically-predicted TCO2 and TAlk. This directly incorporated the inherent nonlinearities of the carbonate system, in a completely mechanistic manner. The model’s empirical coefficients were determined for a target study area of the central North American Pacific continental margin (22–50°N, within 370 km of the coastline), by optimally reproducing a set of historical observations paired with satellite data. The model-predicted pCO2 agreed with the highly variable observations with a root mean squared (RMS) deviation of 0.8 (r = 0.81; r2 = 0.66). This level of accuracy is a significant improvement relative to that of simpler models that did not resolve the biogeochemical sub-regions or that relied on linear dependences on input parameters. Air–sea fluxes based on these pCO2 predictions and satellite-based wind speed measurements suggest that the region is a ∼14 Tg C yr−1 sink for atmospheric CO2 over the 1997–2005 period, with an approximately equivalent uncertainty, compared with a ∼0.5 Tg C yr−1 source predicted by a recent bin-averaging and interpolation-based estimate for the same area.Fil: Hales, Burke. State University of Oregon; Estados UnidosFil: Strutton, Peter G.. University Of Tasmania; AustraliaFil: Saraceno, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones del Mar y la Atmosfera. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones del Mar y la Atmosfera; ArgentinaFil: Letelier, Ricardo. State University of Oregon; Estados UnidosFil: Takahashi, Taro. Lamont-Doherty Earth Observatory; Estados UnidosFil: Feely, Richard. National Oceanic and Atmospheric Administration. Pacific Marine Environmental Laboratory; Estados UnidosFil: Sabine, Christopher. National Oceanic and Atmospheric Administration. Pacific Marine Environmental Laboratory; Estados UnidosFil: Chavez, Francisco. Monterey Bay Aquarium Research Institute; Estados Unido

Iron links river runoff and shelf width to phytoplankton biomass along the U.S. West Coast

A poleward increase in phytoplankton biomass along the West Coast of North America has been attributed to increasing river runoff towards the north. We combine streamflow and shelf width data with satellite-derived estimates of phytoplankton biomass to quantify the relationship between these variables. We find that a combination of winter streamflow and shelf width can account for over 80% of the spatial variance in summer chlorophyll within 50 km of the coast. At a given location, interannual variability in streamflow is not associated with interannual variability in chlorophyll. We attribute these relationships to the role of rivers as suppliers of the micronutrient iron, and the role of the shelf as a ‘capacitor’ for riverine iron, charging during the high-flow winter season and discharging during the upwelling season. Data from the Oregon shelf confirm that, during winter, a significant fraction of riverine iron escapes the estuary and reaches the coastal ocean.Keywords: iron, runoff, productivit

Seasonal cycle of surface ocean pCO₂ on the Oregon shelf

Previous work has shown that the Oregon shelf is a sink for atmospheric carbon dioxide (CO₂) during the upwelling season; however, until now, summertime variability in CO₂ exchange and sign of the flux for the rest of the year were unknown. Observations of the partial pressure of CO₂ (pCO₂) in surface waters from August 2007 to May 2010 from ships and a buoy were used with historical data to produce a composite seasonal cycle for the central Oregon midshelf. These data indicate that the region is highly variable, at times being either a sink or strong source for atmospheric CO₂. Interannual wind variability was an important determining factor in shaping the sink/source nature of this system. Late summer and early autumn was most variable relative to the rest of the year. Winter pCO₂ was near or slightly below atmospheric levels. Strong shelf-wide undersaturated conditions were first observed in early spring and lasted until the upwelling season became developed. Peak upwelling season pCO₂ ranged from 1000 μatm. In July 2008, ship and buoy data revealed previously unobserved high-pCO₂ waters (∼1000 μatm) at the surface. These conditions persisted for nearly 2 months and drove this system to be only a weak net annual atmospheric CO₂ sink of −0.3 ± 6.8 mol m⁻² yr⁻¹. These data showed, for the first time, the seasonal cycle of surface ocean pCO₂ on the central Oregon midshelf and the impact of heretofore undocumented pCO₂ levels on an estimate of sea-air CO₂ flux for this region.This is the publisher's final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://www.agu.org/journals/jc

Fluorene-based fluorescent probes with high two-photon action cross-sections for biological multiphoton imaging applications

Two-photon fluorescence microscopy is a powerful tool for the study of dynamic cellular processes and live-cell imaging. Many commercially available fluorescent probes have been used in multiphoton-based imaging studies despite exhibiting relatively low two-photon absorption cross-section values in the tunability range of ultrafast Ti:sapphire lasers commonly used in multiphoton microscopy imaging. Furthermore, available fluorophores may be plagued with low fluorescence quantum yield and/or photoinstability (i.e., photobleaching) on exposure to the high peak power and photon density provided by the ultrafast laser source. To address the demand for better performing dyes, we prepare fluorophores tailored for multiphoton imaging. These fluorophores are based on the fluorene ring system, known to exhibit high fluorescence quantum yield ( \u3e 0.7) and high photostability. Furthermore, an amine-reactive fluorescent probe for the covalent attachment onto amine-containing biomolecules is also prepared. Epi-fluorescence and two-photon fluorescence microscopy images of H9c2 rat cardiomyoblasts stained with an efficient two-photon absorbing fluorene fluorophore is demonstrated. Additionally, single-photon spectral characteristics of the amine-reactive fluorophore, as well as the two-photon absorption cross sections of its model adduct in solution, and spectral characterization of a bovine serum albumin (BSA) as a model bioconjugate are presented

The phenomenology of mental imagery in people with intellectual disabilities

Objectives: Mental imagery is important in the development and maintenance of psychological disorders and well-being but has been neglected in people with intellectual disabilities. A detailed idiographic analysis of the lived experience of mental imagery in this population is presented. Design: This qualitative study uses interpretative phenomenological analysis (IPA). It involved inclusive research methods with people with intellectual disabilities and other stakeholders (including family members, advocates, support workers and intellectual disability service managers). Methods: Ten individual semi-structured interviews were conducted with people with mild–moderate intellectual disabilities. Participants were opportunistically sampled through organisations providing community services to people with intellectual disabilities in the UK. Two men and eight women (mean age 43 years) participated. Interviews were audio-recorded and analysed using IPA. Results: People with intellectual disabilities are able to experience a range of rich and detailed mental images across all sensory modalities. Participants reported changes in affect based on mental imagery, and an ability to experience both spontaneous and deliberate mental images. The emotional saliency of the object of mental imagery appeared to influence participants' ability to engage with imagery. A number of adaptations make mental imagery more accessible and easier to report. The ability of people with intellectual disabilities to experience vivid mental imagery has important clinical implications for the use of a range of mental imagery interventions with this population. Conclusions: The need to consider mental imagery interventions for this population, and how these can be adapted to ensure accessibility is a priority for people with intellectual disabilities and psychological disorders

A systematic review and narrative synthesis of mental imagery tasks in people with an intellectual disability : implications for psychological therapies

Mental imagery is recognised for its role in both psychological distress and wellbeing, with mental imagery techniques increasingly being incorporated into psychological interventions. In this systematic review and narrative synthesis (PROSPERO 2021: CRD42021240930), we identify and evaluate the evidence base for the phenomenon and phenomenology of mental imagery in people with intellectual disabilities, to ascertain the applicability of such interventions for this population. Electronic searches of nine databases and grey literature identified relevant publications. Two reviewers independently assessed titles and abstracts of retrieved records (n = 8609) and full-text articles (n = 101) against eligibility criteria. Data were extracted and quality appraised. Forty-one papers met our eligibility criteria. The quality and designs were variable. Mental imagery was facilitated through ensuring participants understood tasks, providing opportunity to rehearse tasks (including using concrete prompts) and using scaffolding to help participants elaborate their responses. People with intellectual disabilities can engage with mental imagery, with appropriate adaptations, although the associated phenomenology has not been thoroughly investigated. Mental imagery interventions may be useful for people with intellectual disabilities with appropriate modifications