Atmospheric electric charge transfer in precipitation and associated synoptic conditions

Measurements of Atmospheric Electricity have been made in the unpolluted air of Weardale during conditions of precipitation and in fair weather. An automatic recording system has been built to digitize instrument outputs on paper-tape for subsequent computer analysis. The system ivas installed and run at Lanehead Field Centre and was also used to process magnetic tape recordings from the LandRover mobile station. The system was expanded to include an 1-hour smoothing and sampling action for recording aveiaged values of fair weather Atmospheric Electricity. At times of electrically quiet precipitation, measurements have been made of potential gradient, precipitation current density, space charge density and both polar conductivities. A new method of compensation for displacement currents has been used. Conductivity measurements have revealed a charge separation process close to the ground in rain, but not in snow. Techniques of variance spectrum analysis have been adopted for the precipitation work. Coherency spectra of potential gradient with precipitation current have indicated electrical 'cells' in nimbostratus and their relevance to weather forecasting is discussed. The phase spectra for these two parameters have been examined to measure the height of electrical activity and this is found to coincide with the melting level, and an estimate is made of the conductivity of the charging region of the cloud. Digital filtering of records has disclosed a mechanical-transfer current of space charges, to an exposed rain receiver, opposite to the precipitation current. The diurnal variation of potential gradient at Lanehead has been refined with a further year's continuous observations in fair weather and seasonal differences in the diurnal variations of potential gradient, air- earth -current density and space charge density have been explained by increased convection in summer. The conduction current has been estimated, by the indirect method and the difference between this and the total air-earth current to an exposed plate is attributed to a mechanical-transfer current of space charges. Measurements in light winds have evinced the influence of the electrode effect

Understanding causality and uncertainty in volcanic observations: an example of forecasting eruptive activity on Soufrière Hills Volcano, Montserrat

Following a cessation in eruptive activity it is important to understand how a volcano will behave in the future and when it may next erupt. Such an assessment can be based on the volcano's long-term pattern of behaviour and insights into its current state via monitoring observations. We present a Bayesian network that integrates these two strands of evidence to forecast future eruptive scenarios using expert elicitation. The Bayesian approach provides a framework to quantify the magmatic causes in terms of volcanic effects (i.e., eruption and unrest). In October 2013, an expert elicitation was performed to populate a Bayesian network designed to help forecast future eruptive (in-)activity at Soufrière Hills Volcano. The Bayesian network was devised to assess the state of the shallow magmatic system, as a means to forecast the future eruptive activity in the context of the long-term behaviour at similar dome-building volcanoes. The findings highlight coherence amongst experts when interpreting the current behaviour of the volcano, but reveal considerable ambiguity when relating this to longer patterns of volcanism at dome-building volcanoes, as a class. By asking questions in terms of magmatic causes, the Bayesian approach highlights the importance of using short-term unrest indicators from monitoring data as evidence in long-term forecasts at volcanoes. Furthermore, it highlights potential biases in the judgements of volcanologists and identifies sources of uncertainty in terms of magmatic causes rather than scenario-based outcomes

Emergency planning and mitigation at Vesuvius: A new evidence-based approach

Disasters from explosive volcanic eruptions are infrequent and experience in emergency planning and mitigation for such events remains limited. The need for urgently developing more robust methods for risk assessment and decision making in volcanic crises has become increasingly apparent as world populations continue to expand in areas of active explosive volcanism. Nowhere is this more challenging than at Vesuvius, Italy, with hundreds of thousands of people living on the flanks of one of the most dangerous volcanoes in the world. We describe how a new paradigm, evidence-based volcanology, has been applied in EXPLORIS to contribute to crisis planning and management for when the volcano enters its next state of unrest, as well as in long-term land-use planning. The analytical approach we adopted enumerates and quantifies all the processes and effects of the eruptive hazards of the volcano known to influence risk, a scientific challenge that combines field data on the vulnerability of the built environment and humans in past volcanic disasters with theoretical research on the state of the volcano, and including evidence from the field on previous eruptions as well as numerical simulation modelling of eruptive processes. Formal probabilistic reasoning under uncertainty and a decision analysis approach have provided the basis for the development of an event tree for a future range of eruption types with probability paths and hypothetical casualty outcomes for risk assessment. The most likely future eruption scenarios for emergency planning were derived from the event tree and elaborated upon from the geological and historical record. Modelling the impacts in these scenarios and quantifying the consequences for the circumvesuvian area provide realistic assessments for disaster planning and for showing the potential risk–benefit of mitigation measures, the main one being timely evacuation, but include for consideration protecting buildings against dilute, low dynamic pressure surges, and temporary roof supports in the most vulnerable buildings, as well as hardening infrastructure and lifelines. This innovative work suggests that risk-based methods could have an important role in crisis management at cities on volcanoes and small volcanic islands

Assessing future vent opening locations at the Somma-Vesuvio volcanic complex:1. A new information geodatabase with uncertainty characterizations

This study presents new and revised data sets about the spatial distribution of past volcanic vents, eruptive fissures, and regional/local structures of the Somma‐Vesuvio volcanic system (Italy). The innovative features of the study are the identification and quantification of important sources of uncertainty affecting interpretations of the data sets. In this regard, the spatial uncertainty of each feature is modeled by an uncertainty area, i.e., a geometric element typically represented by a polygon drawn around points or lines. The new data sets have been assembled as an updatable geodatabase that integrates and complements existing databases for Somma‐Vesuvio. The data are organized into 4 data sets and stored as 11 feature classes (points and lines for feature locations and polygons for the associated uncertainty areas), totaling more than 1700 elements. More specifically, volcanic vent and eruptive fissure elements are subdivided into feature classes according to their associated eruptive styles: (i) Plinian and sub‐Plinian eruptions (i.e., large‐ or medium‐scale explosive activity); (ii) violent Strombolian and continuous ash emission eruptions (i.e., small‐scale explosive activity); and (iii) effusive eruptions (including eruptions from both parasitic vents and eruptive fissures). Regional and local structures (i.e., deep faults) are represented as linear feature classes. To support interpretation of the eruption data, additional data sets are provided for Somma‐Vesuvio geological units and caldera morphological features. In the companion paper, the data presented here, and the associated uncertainties, are used to develop a first vent opening probability map for the Somma‐Vesuvio caldera, with specific attention focused on large or medium explosive events.Published4336-43566V. Pericolosità vulcanica e contributi alla stima del rischioJCR Journa

Mobile Resource Guarantees and Policies

Abstract. This paper introduces notions of resource policy for mobile code to be run on smart devices, to integrate with the proof-carrying code architecture of the Mobile Resource Guarantees (MRG) project. Two forms of policy are used: guaranteed policies which come with proofs and target policies which describe limits of the device. A guaranteed policy is expressed as a function of a methods input sizes, which determines a bound on consumption of some resource. A target policy is defined by a constant bound and input constraints for a method. A recipient of mobile code chooses whether to run methods by comparing between a guaranteed policy and the target policy. Since delivered code may use methods implemented on the target machine, guaranteed policies may also be provided by the platform; they appear symbolically as assumptions in delivered proofs. Guaranteed policies entail proof obligations that must be established from the proof certificate. Before proof, a policy checker ensures that the guaranteed policy refines the target policy; our policy format ensures that this step is tractable and does not require proof. Delivering policies thus mediates between arbitrary target requirements and the desirability to package code and certificate only once.

Use of structured expert judgment to forecast invasions by bighead and silver carp in Lake Erie

Identifying which nonindigenous species will become invasive and forecasting the damage they will cause is difficult and presents a significant problem for natural resource management. Often, the data or resources necessary for ecological risk assessment are incomplete or absent, leaving environmental decision makers ill equipped to effectively manage valuable natural resources. Structured expert judgment (SEJ) is a mathematical and performance‐based method of eliciting, weighting, and aggregating expert judgments. In contrast to other methods of eliciting and aggregating expert judgments (where, for example, equal weights may be assigned to experts), SEJ weights each expert on the basis of his or her statistical accuracy and informativeness through performance measurement on a set of calibration variables. We used SEJ to forecast impacts of nonindigenous Asian carp (Hypophthalmichthys spp.) in Lake Erie, where it is believed not to be established. Experts quantified Asian carp biomass, production, and consumption and their impact on 4 fish species if Asian carp were to become established. According to experts, in Lake Erie Asian carp have the potential to achieve biomass levels that are similar to the sum of biomasses for several fishes that are harvested commercially or recreationally. However, the impact of Asian carp on the biomass of these fishes was estimated by experts to be small, relative to long term average biomasses, with little uncertainty. Impacts of Asian carp in tributaries and on recreational activities, water quality, or other species were not addressed. SEJ can be used to quantify key uncertainties of invasion biology and also provide a decision‐support tool when the necessary information for natural resource management and policy is not available.El Uso de Juicio Experto Estructurado para Predecir Invasiones de Carpas Asiáticas en el Lago ErieResumenIdentificar cuáles especies no‐nativas se volverán invasoras y predecir el daño que causarán es complicado y presenta un problema significativo para el manejo de recursos naturales. Con frecuencia los datos o recursos necesarios para la evaluación de riesgo ecológico están incompletos o son inexistentes, lo que deja mal equipados a quienes toman las decisiones ambientales para manejar efectivamente recursos naturales valiosos. El juicio experto estructurado (JEE) es un método con bases matemáticas y de desempeño para obtener, sopesar y agregar juicios expertos. En contraste con otros métodos de obtención y agregación de juicios expertos (donde, por ejemplo, se le pueden asignar pesos iguales a los expertos), JEE sopesa a cada experto con base en su asertividad estadística y capacidad de informar por medio de la medida de desempeño en un conjunto de variables de calibración. Usamos JEE para predecir los impactos de las carpas asiáticas no‐nativas Hypophthalmichthys spp. en el Lago Erie, donde se cree que no se ha establecido. Los expertos cuantificaron la biomasa, producción y consumo de la carpa asiática y su impacto sobre cuatro especies de peces si la carpa asiática se llegara a establecer en el lago. De acuerdo a los expertos, en el Lago Erie, la carpa asiática tiene el potencial de adquirir niveles de biomasa similares a la suma de biomasa de varios peces que se han cultivado comercialmente o recreativamente. Sin embargo, se estimó por los expertos que el impacto de la carpa asiática sobre la biomasa de estos peces sería pequeño, con poca incertidumbre. Los impactos de la carpa asiática sobre los tributarios y las actividades recreativas, la calidad del agua o sobre otras especies no se evaluaron. El JEE puede usarse para cuantificar incertidumbres clave de la biología de la invasión y también proporcionar una herramienta de apoyo para las decisiones cuando la información necesaria para el manejo de los recursos naturales y la política no está disponible.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110571/1/cobi12369.pd

A qualitative analysis of the effectiveness of telehealthcare devices (i) are they meeting the needs of end-users?

Background: There are many telehealthcare devices currently available ranging from personal alarms, automated pill dispensers and fall detectors through to monitoring devices for blood sugar, blood pressure and heart rate. Many devices remain unused once acquired or shortly after a period of initial use. Methods: The study used a qualitative design involving focus groups and interviews. End users’ opinions of telehealthcare devices were examined through focus groups along with the views of market experts and key supply chain players through telephone interviews to ascertain their views on the devices. The data were recorded, transcribed and analysed thematically. Results: Amongst the wide range of user issues associated with telehealthcare devices two themes merited particular attention: design characteristics and the lack of focus on end-user needs. Our findings suggested that few telehealthcare devices appear to be developed based on the principles of user-centred design. Consequently, many were non-intuitive to use, with the majority of the focus group participants not recognising the purpose of the devices from their appearance alone. Conclusions: Greater input from real end-users rather than “proxy” users such as carers, professional users or technologists is required when developing telehealthcare devices or systems. Design should be focussed on intuitive use to enable the user to successfully achieve what is required from the devices. This may require the existing supplier—driven market focus to be challenged, but could improve the contribution of technology to improving healthcare

A matched comparison study of hepatitis C treatment outcomes in the prison and community setting, and an analysis of the impact of prison release or transfer during therapy

Prisoners are a priority group for hepatitis C (HCV) treatment. Although treatment durations will become shorter using directly acting antivirals (DAAs), nearly half of prison sentences in Scotland are too short to allow completion of DAA therapy prior to release. The purpose of this study was to compare treatment outcomes between prison- and community-based patients and to examine the impact of prison release or transfer during therapy. A national database was used to compare treatment outcomes between prison treatment initiates and a matched community sample. Additional data were collected to investigate the impact of release or transfer on treatment outcomes. Treatment-naïve patients infected with genotype 1/2/3/4 and treated between 2009 and 2012 were eligible for inclusion. 291 prison initiates were matched with 1137 community initiates: SVRs were 61% (95% CI 55%-66%) and 63% (95% CI 60%-66%), respectively. Odds of achieving a SVR were not significantly associated with prisoner status (P=.33). SVRs were 74% (95% CI 65%-81%), 59% (95% CI 42%-75%) and 45% (95% CI 29%-62%) among those not released or transferred, transferred during treatment, or released during treatment, respectively. Odds of achieving a SVR were significantly associated with release (P<.01), but not transfer (P=.18). Prison-based HCV treatment achieves similar outcomes to community-based treatment, with those not released or transferred during treatment doing particularly well. Transfer or release during therapy should be avoided whenever possible, using anticipatory planning and medical holds where appropriate