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An overview of the Lagrangian experiments undertaken during the North Atlantic regional Aerosol Characterisation Experiment (ACE-2)
One of the primary aims of the North Atlantic regional Aerosol Characterisation Experiment
(ACE-2) was to quantify the physical and chemical processes affecting the evolution of the
major aerosol types over the North Atlantic. The best, practical way of doing this is in a
Lagrangian framework where a parcel of air is sampled over several tens of hours and its
physical and chemical properties are intensively measured. During the intensive observational
phase of ACE-2, between 15 June 1997 and 24 July 1997, 3 cloudy Lagrangian experiments
and 3 cloud-free, Lagrangian experiments were undertaken between the south west tip of the
Iberian Peninsula and the Canary Islands. This paper gives an overview of the aims and logistics
of all of the Lagrangian experiments and compares and contrasts them to provide a framework
for the more focused Lagrangian papers in this issue and future process modelling studies and
parametrisation development. The characteristics of the cloudy Lagrangian experiments were
remarkably different, enabling a wide range of different physical and chemical processes to be
studied. In the 1st Lagrangian, a clean maritime air mass was sampled in which salt particle
production, due to increased wind speed, dominated the change in the accumulation mode
concentrations. In the 2nd Lagrangian, extensive cloud cover resulted in cloud processing of
the aerosol in a polluted air mass, and entrainment of air from the free troposphere influenced
the overall decrease in aerosol concentrations in the marine boundary layer (MBL). Very little
change in aerosol characteristics was measured in the 3rd Lagrangian, where the pollution in
the MBL was continually being topped up by entraining air from a residual continental boundary
layer (CBL) above. From the analysis of all the Lagrangian experiments, it has been possible
to formulate, and present here, a generalised description of a European continental outbreak
of pollution over the sub-tropical North Atlantic
Clear-sky closure studies of lower tropospheric aerosol and water vapor during ACE-2 using airborne sunphotometer, airborne in-situ, space-borne, and ground-based measurements
We report on clear-sky column closure experiments (CLEARCOLUMN) performed in the Canary Islands during the second Aerosol Characterization Experiment (ACE-2) in June/July 1997. We present CLEARCOLUMN results obtained by combining airborne sunphotometer and in-situ (optical particle counter, nephelometer, and absorption photometer) measurements taken aboard the Pelican aircraft, space-borne NOAA/AVHRR data and ground-based lidar and sunphotometer measurements. During both days discussed here, vertical profiles flown in cloud-free air masses revealed 3 distinctly different layers: a marine boundary layer (MBL) with varying pollution levels, an elevated dust layer, and a very clean layer between the MBL and the dust layer. A key result of this study is the achievement of closure between extinction or layer aerosol optical depth (AOD) computed from continuous in-situ aerosol size-distributions and composition and those measured with the airborne sunphotometer. In the dust, the agreement in layer AOD (λ=380–1060 nm) is 3–8%. In the MBL there is a tendency for the in-situ results to be slightly lower than the sunphotometer measurements (10–17% at λ=525 nm), but these differences are within the combined error bars of the measurements and computations
US Cystic Fibrosis Foundation and European Cystic Fibrosis Society consensus recommendations for the management of non-tuberculous mycobacteria in individuals with cystic fibrosis
Non-tuberculous mycobacteria (NTM) are ubiquitous environmental organisms that can cause chronic pulmonary infection, particularly in individuals with preexisting inflammatory lung disease such as cystic fibrosis(CF). Pulmonary disease caused by NTM has emerged as a major threat to the health of individuals with CF but remains difficult to diagnose and problematic to treat. In response to this challenge, the US Cystic Fibrosis Foundation (CFF) and the European Cystic Fibrosis Society (ECFS) convened an expert panel of specialists to develop consensus recommendations for the screening, investigation, diagnosis and management of NTM pulmonary disease in individuals with CF. Nineteen experts were invited to participate in the recommendation development process. Population, Intervention, Comparison, Outcome (PICO) methodology and systematic literature reviews were employed to inform draft recommendations. An anonymous voting process was used by the committee to reach consensus. All committee members were asked to rate each statement on a scale of: 0, completely disagree, to 9, completely agree; with 80% or more of scores between 7 and 9 being considered ‘good’ agreement. Additionally, the committee solicited feedback from the CF communities in the USA and Europe and considered the feedback in the development of the final recommendation statements. Three rounds of voting were conducted to achieve 80% consensus for each recommendation statement. Through this process, we have generated a series of pragmatic, evidence-based recommendations for the screening, investigation, diagnosis and treatment of NTM infection in individuals with CF as an initial step in optimising management for this challenging condition
The psychological science accelerator’s COVID-19 rapid-response dataset
In response to the COVID-19 pandemic, the Psychological Science Accelerator coordinated three large-scale psychological studies to examine the effects of loss-gain framing, cognitive reappraisals, and autonomy framing manipulations on behavioral intentions and affective measures. The data collected (April to October 2020) included specific measures for each experimental study, a general questionnaire examining health prevention behaviors and COVID-19 experience, geographical and cultural context characterization, and demographic information for each participant. Each participant started the study with the same general questions and then was randomized to complete either one longer experiment or two shorter experiments. Data were provided by 73,223 participants with varying completion rates. Participants completed the survey from 111 geopolitical regions in 44 unique languages/dialects. The anonymized dataset described here is provided in both raw and processed formats to facilitate re-use and further analyses. The dataset offers secondary analytic opportunities to explore coping, framing, and self-determination across a diverse, global sample obtained at the onset of the COVID-19 pandemic, which can be merged with other time-sampled or geographic data
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