Characterisation and airborne deployment of a new counterflow virtual impactor inlet

A new counterflow virtual impactor (CVI) inlet is introduced with details of its design, laboratory characterisation tests and deployment on an aircraft during the 2011 Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE). The CVI inlet addresses three key issues in previous designs; in particular, the inlet operates with: (i) negligible organic contamination; (ii) a significant sample flow rate to downstream instruments (∼15 l min^(−1)) that reduces the need for dilution; and (iii) a high level of accessibility to the probe interior for cleaning. Wind tunnel experiments characterised the cut size of sampled droplets and the particle size-dependent transmission efficiency in various parts of the probe. For a range of counter-flow rates and air velocities, the measured cut size was between 8.7–13.1 μm. The mean percentage error between cut size measurements and predictions from aerodynamic drag theory is 1.7%. The CVI was deployed on the Center for Interdisciplinary Remotely Piloted Aircraft Studies (CIRPAS) Twin Otter for thirty flights during E-PEACE to study aerosol-cloud-radiation interactions off the central coast of California in July and August 2011. Results are reported to assess the performance of the inlet including comparisons of particle number concentration downstream of the CVI and cloud drop number concentration measured by two independent aircraft probes. Measurements downstream of the CVI are also examined from one representative case flight coordinated with shipboard-emitted smoke that was intercepted in cloud by the Twin Otter

Studying Public Health Law::Principles, Politics, and Populations as Patients

Public health law is firmly establishing itself as a crucial area of scholarly inquiry. Its vital importance has been sharply underscored following the outbreak of COVID-19, in response to which we have seen the institution of extreme legal measures—suchas the UK’s Coronavirus Act 2020—in efforts to control and contain the spread ofthe disease. The pandemic has also starkly exposed the complex nature of the regulatory challenges, nationally, internationally, and globally, to which such public health problems give rise. In approaching these, and other questions concerning the public’s health, such as non-communicable disease, public health law, as a field, brings notable distinctive features: these include a practical focus on populations, institutions, the prevention of ill health, protection of good health, and thepromotion of positive states of well-being; and concomitant critical approaches rooted in theories of social justice as contrasted with more narrow biomedical ethics. Such features make it in some senses atypical territory within the field of health law. Furthermore, the inherent role of political institutions places law conceptually within public health in a way that may be seen as distinguishable from law’s relationship with clinical medicine. This chapter explains how the broad reach and distinct features of public health require a commensurately broad approach to conceptualising public health law, and how distinct practical and theoretical features may be integrated into academic public health law. It also shows how public health law, with its distinct conceptualisations concerning ‘the body’ of medical jurisprudence, can both challenge and enrich medico-legal studies, and bring important perspectives within the broader field of health law

Observations of continental biogenic impacts on marine aerosol and clouds off the coast of California

During the 2011 Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE) and 2013 Nucleation in California Experiment (NiCE) field campaigns, a predominantly organic aerosol (> 85% by mass) was observed in the free troposphere over marine stratocumulus off the coast of California. These particles originated from a densely forested region in the Northwestern United States. The organic mass spectrum resolved by positive matrix factorization is consistent with the mass spectra of previously measured biogenic organic aerosol. Particulate organic mass exhibits a latitudinal gradient that corresponds to the geographical distribution of vegetation density and composition, with the highest concentration over regions impacted by densely populated monoterpene sources. Due to meteorological conditions during summer months, cloud-clearing events transport aerosol from the Northwestern United States into the free troposphere above marine stratocumulus. Based on the variation of meteorological variables with altitude, dry air containing enhanced biogenic organic aerosol is shown to entrain into the marine boundary layer. Fresh impacts on cloud water composition are observed north of San Francisco, CA which is consistent with fresh continental impacts on the marine atmosphere at higher latitudes. Continental aerosol size distributions are bimodal. Particles in the 100 nm mode are impacted by biogenic sources, while particles in the ∼ 30 nm mode may originate from fresh biogenic emissions. Continental aerosol in the 100 nm mode is cloud condensation nuclei active and may play a role in modulating marine stratocumulus microphysics

Aide memoire for a balancing act? Critiquing the 'Balance Sheet' approach to best interest decision-making

The balance sheet is commonly used as a deliberative approach to decide best interests in Court of Protection and family cases in England and Wales, since Thorpe LJ in Re A (Male Sterilisation) described the balance sheet as a tool to enable judges and best interests decision-makers to quantify, compare, and calculate the different options at play. Recent judgments have critically reflected on the substance and practical function of the balance sheet approach, highlighting the practical stakes of its implicit conceptual assumptions and normative commitments. Using parallel debates in proportionality, we show that the balance sheet imports problematic assumptions of commensurability and aggregation, which can both overdetermine the outcome of best interests decisions and obfuscate the actual process of judicial deliberation. This means that the decision-making of judges and best interests assessors more generally could fail to properly reflect the nature of values at stake, as well as the skills of practical judgment needed to compare such values with sensitivity and nuance. The paper argues that critical reflection of the balance sheet makes vital space for a more contextualised, substantive mode of deliberation which emphasises skills of qualitative evaluation towards enhancing conditions of articulation around the range of values involved in best interests decision-making

Marine Boundary Layer Clouds Associated with Coastally Trapped Disturbances: Observations and Model Simulations

This work has been accepted to Journal of Atmospheric Sciences. The AMS does not guarantee that the copy provided here is an accurate copy of the final published work.Modeling marine low clouds and fog in coastal environments remains an outstanding challenge due to the inherently complex ocean–land–atmosphere system. This is especially important in the context of global circulation models due to the profound radiative impact of these clouds. This study utilizes aircraft and satellite measurements, in addition to numerical simulations using the Weather Research and Forecasting (WRF) Model, to examine three well-observed coastally trapped disturbance (CTD) events from June 2006, July 2011, and July 2015. Cloud water-soluble ionic and elemental composition analyses conducted for two of the CTD cases indicate that anthropogenic aerosol sources may impact CTD cloud decks due to synoptic-scale patterns associated with CTD initiation. In general, the dynamics and thermodynamics of the CTD systems are well represented and are relatively insensitive to the choice of physics parameterizations; however, a set of WRF simulations suggests that the treatment of model physics strongly influences CTD cloud field evolution. Specifically, cloud liquid water path (LWP) is highly sensitive to the choice of the planetary boundary layer (PBL) scheme; in many instances, the PBL scheme affects cloud extent and LWP values as much as or more than the microphysics scheme. Results suggest that differences in the treatment of entrainment and vertical mixing in the Yonsei University (nonlocal) and Mellor–Yamada–Janjić (local) PBL schemes may play a significant role. The impact of using different driving models—namely, the North American Mesoscale Forecast System (NAM) 12-km analysis and the NCEP North American Regional Reanalysis (NARR) 32-km products—is also investigated

Marine Boundary Layer Clouds Associated with Coastally Trapped Disturbances: Observations and Model Simulations

Modeling marine low clouds and fog in coastal environments remains an outstanding challenge due to the inherently complex ocean–land–atmosphere system. This is especially important in the context of global circulation models due to the profound radiative impact of these clouds. This study utilizes aircraft and satellite measurements, in addition to numerical simulations using the Weather Research and Forecasting (WRF) Model, to examine three well-observed coastally trapped disturbance (CTD) events from June 2006, July 2011, and July 2015. Cloud water-soluble ionic and elemental composition analyses conducted for two of the CTD cases indicate that anthropogenic aerosol sources may impact CTD cloud decks due to synoptic-scale patterns associated with CTD initiation. In general, the dynamics and thermodynamics of the CTD systems are well represented and are relatively insensitive to the choice of physics parameterizations; however, a set of WRF simulations suggests that the treatment of model physics strongly influences CTD cloud field evolution. Specifically, cloud liquid water path (LWP) is highly sensitive to the choice of the planetary boundary layer (PBL) scheme; in many instances, the PBL scheme affects cloud extent and LWP values as much as or more than the microphysics scheme. Results suggest that differences in the treatment of entrainment and vertical mixing in the Yonsei University (nonlocal) and Mellor–Yamada–Janjić (local) PBL schemes may play a significant role. The impact of using different driving models—namely, the North American Mesoscale Forecast System (NAM) 12-km analysis and the NCEP North American Regional Reanalysis (NARR) 32-km products—is also investigated

A behavioural change package to prevent hand dermatitis in nurses working in the national health service (the SCIN trial): study protocol for a cluster randomised controlled trial

BACKGROUND: Hand dermatitis can be a serious health problem in healthcare workers. While a range of skin care strategies and policy directives have been developed in recent years to minimise the risk, their effectiveness and cost-effectiveness remain unclear. Evidence now suggests that psychological theory can facilitate behaviour change with respect to improved hand care practices. Therefore, we will test the hypothesis that a behavioural change intervention to improve hand care, based on the Theory of Planned Behaviour and implementation intentions, coupled with provision of hand moisturisers, can produce a clinically useful reduction in the occurrence of hand dermatitis, when compared to standard care, among nurses working in the UK National Health Service (NHS) who are particularly at risk. Secondary aims will be to assess impacts on participants’ beliefs and behaviour regarding hand care. In addition, we will assess the cost-effectiveness of the intervention in comparison with normal care. METHODS/DESIGN: We will conduct a cluster randomised controlled trial at 35 NHS hospital trusts/health boards/universities, focussing on student nurses with a previous history of atopic disease or hand eczema and on nurses in intensive care units. Nurses at ‘intervention-light’ sites will be managed according to what would currently be regarded as best practice, with provision of an advice leaflet about optimal hand care to prevent hand dermatitis and encouragement to contact their occupational health (OH) department early if hand dermatitis occurs. Nurses at ‘intervention-plus’ sites will additionally receive a behavioural change programme (BCP) with on-going active reinforcement of its messages, and enhanced provision of moisturising cream. The impact of the interventions will be compared using information collected by questionnaires and through standardised photographs of the hands and wrists, collected at baseline and after 12 months follow-up. In addition, we will assemble relevant economic data for an analysis of costs and benefits, and collect information from various sources to evaluate processes. Statistical analysis will be by multi-level regression modelling to allow for clustering by site, and will compare the prevalence of outcome measures at follow-up after adjustment for values at baseline. The principal outcome measure will be the prevalence of visible hand dermatitis as assessed by the study dermatologists. In addition, several secondary outcome measures will be assessed. DISCUSSION: This trial will assess the clinical and cost effectiveness of an intervention to prevent hand dermatitis in nurses in the United Kigdom. TRIAL REGISTRATION: ISRCTN53303171: date of registration, 21 June 2013