Discharge Scheme Research Articles

Plasma-catalytic dry reforming of CH4: Effects of plasma-generated species on the surface chemistry

By means of steady-state experiments and a global model, we studied the effects of plasma-generated reactive species on the surface chemistry and coking in plasma-catalytic CH4/CO2 reforming at reduced pressure (8–40 kPa). We used a hybrid ZDPlasKin-CHEMKIN model to predict the species densities over time. The detailed plasma-catalytic mechanism consists of the plasma discharge scheme, a gas-phase chemistry set and a surface mechanism. Our experimental results show that the coupling of Ni/SiO2 catalyst with plasma is more effective in CH4/CO2 activation and conversion than unpacked DBD plasma, with syngas being the main products. The highest total conversion of 16 % was achieved at 8000 V and 473 K, with corresponding CO and H2 yields of 15 % and 12 %, respectively. The reactants conversion and product selectivity are well captured by the kinetic model. Our simulation results suggest that vibrational species and radicals can accelerate the dissociative adsorption and Eley-Rideal (E-R) reactions. Path flux analysis shows that E-R reactions dominate the surface reaction pathways, which differs from thermal catalysis, indicating that the coupling of non-equilibrium plasma and catalysis can effectively shift the formation and consumption pathways of important adsorbates. For instance, our model suggests that HCOO(s) is primarily generated through the E-R reaction CO2(v) + H(s) → HCOO(s), while the hydrogenation reaction HCOO(s) + H → HCOOH(s) is the main source of HCOOH(s). Carbon deposition on the catalyst surface is primarily formed through the stepwise dehydrogenation of CH4, while the E-R reactions enhanced by plasma-generated H and O atoms dominate the consumption of carbon deposition. This work provides new insights into the effects of reactive species on the surface chemistry in plasma-catalytic CH4/CO2 reforming.

Zero liquid discharge management: optimizing sustainable reverse osmosis desalination practices

This study introduces a Zero Liquid Discharge (ZLD) scheme for Reverse Osmosis (RO) desalination, integrating ultra-filtration pretreatment and Electrodialysis (ED) for brine concentration. The scheme divides brine reject into fractions, directing them to an electrolyser and evaporator powered by renewable energy sources. Notable findings include the treatment plant's capability to produce 792 cubic meters of fresh water daily, while decreasing salt concentration from 4,660 ppm to 30 ppm, showcasing efficient desalination. Additionally, recycling fractions of RO unit waste to various components enhances resource efficiency. The study highlights the daily production of 2,269.27 kg of hydrogen, coupled with minimal electricity consumption of 74,885.91 kWh, thereby improving overall energy efficiency. Furthermore, the utilization of solar energy significantly reduces reliance on fossil fuels, thereby promoting sustainability and mitigating the environmental impacts associated with traditional energy sources. Solar energy is a clean, renewable resource that helps decrease greenhouse gas emissions and other pollutants, contributing to cleaner air and a healthier planet. This shift towards renewable energy is crucial in addressing climate change and ensuring a sustainable future for generations to come. In the context of desalination, emphasizing environmental preservation and water security is paramount. Desalination processes, while providing essential fresh water in arid regions, often produce brine as a byproduct. The brine, with a high salt concentration of 13,648 ppm, poses a disposal challenge that can negatively impact marine ecosystems if not managed properly. This is where Zero Liquid Discharge (ZLD) systems come into play. With a ZLD index of 2.7%, these systems ensure that all wastewater is treated and reused, leaving no liquid waste behind. ZLD technology captures and recycles every drop of water, converting waste into reusable resources, thus minimizing environmental harm. The model showcased a significant decrease in brackish water extraction from 1,200 cubic meters per day to 871.52 cubic meters per day, marking a notable 27% reduction. These results highlight the promising effectiveness of the proposed ZLD scheme in enhancing the efficiency of brackish water treatment, demonstrating its potential to significantly reduce the demand for fresh water resources while achieving sustainable desalination practices. This article will present a detailed yet a simple description of reverse osmosis and ZLD, how do they correlate and how these two technologies represent the future of water treatment.

Evaluation of enhanced nanofiltration membranes for improving magnesium recovery schemes from seawater/brine: Integrating experimental performing data with a techno-economic assessment

The global demand for valuable metals and minerals necessitates the exploration of alternative, sustainable approaches to mineral recovery. Seawater mining has emerged as a promising option, offering a vast reserve of minerals and an environmentally friendly alternative to land-based mining. Among the various techniques, Nanofiltration (NF) has gained significant attention as a preliminary treatment step in Minimum Liquid Discharge (MLD) and Zero Liquid Discharge (ZLD) schemes. This study focused on the potential of two underexplored commercial polyamide based NF membranes, Synder NFX and Vontron VNF1, with enhanced divalent over monovalent separation factors, in optimizing the extraction of magnesium hydroxide (Mg(OH)2) from seawater and seawater reverse osmosis (SWRO) brines. The research encompassed a thorough characterization of the membranes utilizing advanced physic-chemical analytical techniques, followed by rigorous experimental assessments using synthetic seawater and SWRO brine in concentration configuration. The findings highlighted the superior selectivity of NFX for magnesium recovery from SWRO brine and the promising concentration factors of VNF1 for seawater treatment. Cross-validation of experimental data with a mathematical model demonstrated the model's reliability as a process design tool in predicting membrane performance. A comprehensive techno-economic evaluation demonstrates the potential of NFX, operating optimally at 23 bar pressure and 70% permeate recovery rate, to yield an estimated annual revenue of 5.683 M€/yr through Mg(OH)2 production from SWRO brine for a plant with a nominal capacity of 0.8 Mm3/y. This research shed light on the promising role of NF membranes in enhancing mineral recovery taking benefit of their separation factors and emphasizes the economic viability of leveraging NF technology for maximizing magnesium recovery from seawater and SWRO brines.

Maze-solving in a plasma system based on functional analogies to reinforcement-learning model.

Maze-solving is a classical mathematical task, and is recently analogously achieved using various eccentric media and devices, such as living tissues, chemotaxis, and memristors. Plasma generated in a labyrinth of narrow channels can also play a role as a route finder to the exit. In this study, we experimentally observe the function of maze-route findings in a plasma system based on a mixed discharge scheme of direct-current (DC) volume mode and alternative-current (AC) surface dielectric-barrier discharge, and computationally generalize this function in a reinforcement-learning model. In our plasma system, we install two electrodes at the entry and the exit in a square lattice configuration of narrow channels whose cross section is 1×1 mm2 with the total length around ten centimeters. Visible emissions in low-pressure Ar gas are observed after plasma ignition, and the plasma starting from a given entry location reaches the exit as the discharge voltage increases, whose route converging level is quantified by Shannon entropy. A similar short-path route is reproduced in a reinforcement-learning model in which electric potentials through the discharge voltage is replaced by rewards with positive and negative sign or polarity. The model is not rigorous numerical representation of plasma simulation, but it shares common points with the experiments along with a rough sketch of underlying processes (charges in experiments and rewards in modelling). This finding indicates that a plasma-channel network works in an analog computing function similar to a reinforcement-learning algorithm slightly modified in this study.

Pioneering minimum liquid discharge desalination: A pilot study in Lampedusa Island

Minimum Liquid Discharge (MLD) and Zero Liquid Discharge (ZLD) schemes have been widely proposed in the recent scientific literature not only as a possible solution to brine disposal but also as a non-conventional sustainable source of raw materials. Nevertheless, very few works have pushed the idea towards a real demonstration activity, and this somehow limits the reliability that such schemes have with respect to the real implementation potential at the industrial scale. In this work, for the first time in the literature, an integrated treatment chain for the sustainable production of freshwater and minerals has been demonstrated at a pre-industrial scale, in the island of Lampedusa (Italy). The treatment chain included a Nanofiltration (NF) step to separate monovalent and bivalent ions, followed by a Multi-Effect Distillation (MED) unit, powered by waste heat from a Thermal Power plant, generating high-quality water (<30 μS/cm) and an ultra-concentrated brine. The latter was treated in Evaporation Ponds (EPs) to generate high purity NaCl (>99 %). On the other side, the NF retentate was treated to selectively recover magnesium and calcium hydroxides (Mg(OH)2 purity up to 98 %) in a novel Multiple Feed-Plug Flow Reactor (MF-PFR). The resulting brine fed an ElectroDialysis with Bipolar Membranes unit (EDBM), generating in-situ alkaline and acidic solutions: chemicals needed for internal usage in the plant. All units were successfully tested, reaching satisfactory performance indicators. Furthermore, the stability of each unit during the daily operational run was assessed and successfully achieved, demonstrating not only the technical feasibility of the proposed demo plant, but also the feasibility of MLD as a sustainable alternative for minerals recovery.

System-Based Protection Method for High-Voltage Pulse Generator Switching Units in Biomass Electroporation

Background High-voltage pulsed electric field (PEF) technology has emerged as a promising technique for enhancing cell membrane permeabilization for biotechnological and medical applications. Given the parametric instability and low resistivity of biomass when used it as an electrical load, it is imperative for the switching unit to meet specific requirements in terms of load capacity and protection against overloads and short circuits. Methods To construct generators capable of producing high-voltage pulses in the microsecond and millisecond duration ranges, we are incorporating a switching unit that employs a hardware-software method to safeguard critical transistors against overloads and short-circuit currents. Our strategy revolves around utilizing the energy storage capacitor (ESC) both as a means of energy storage and as a current sensor. By monitoring the voltage drop during discharge, we can accurately estimate current parameters. The occurrence of an excessively rapid discharge from the ESC serves as an indicator of a short circuit. The microcontroller calculates ESC discharge limits based on preset parameters within a defined timeframe. Should this limit be exceeded, the system promptly interrupts to address the pulse responsible for the short circuit and halts the further supply of remaining pulses to the load. This sophisticated approach ensures the protection and integrity of the system in the face of potential overloads or short circuits. Results Applying a systemic approach in the design of the presented implementation of protection for key transistors in the switching node from overload and short-circuit current for high-voltage pulse generators (HVPG) in the microsecond and millisecond duration ranges allows for a simpler circuit solution. In this case, the system approach also provides a unified control principle when implementing the considered option for organizing protection, regardless of the number and type of transistors or solid-state switching modules used and connected in parallel. Conclusions The configuration and protective circuitry presented in the article are specifically tailored for shielding switching elements from short-circuit currents, with a primary focus on their application in high-voltage pulse generators (HVPG). These generators are commonly employed in the high-voltage pulse treatment of diverse and unstable loads during the electroporation of biomass. The technical solution expounded in the article is intended for use in the switching nodes of HVPG, particularly those with discharge circuits constructed based on a direct capacitive discharge scheme. Notably, this protection configuration introduces local innovation and is characterized by the circuit's simplicity, achieved through the effective utilization of existing system resources. This protective variant for HVPG switches is particularly well-suited for devices utilized in versatile technological installations with relatively lower performance levels.

A person-centred approach to help services and commissioners to improve the experience of people who are homeless and secure better sustainability.

Successful implementation of evidence-based services in health and social care depends largely on the fit of the services with the values and priorities of users who are shaping and participating in their delivery and use. When looking at the implementation of innovative specialist hospital discharge schemes for people who are homeless, there is a lack of knowledge on homeless people’s preferences and perspectives on receiving out-of-hospital care.&#x0D; In England, the Department of Health and Social Care, Ministry for Housing and Local Government and Ministry of Justice allocated £16 million to further develop and test out hospital care for people experiencing homelessness. The out-of-hospital care model programme is seeking to scale successful hospital discharge models that were shown to be effective and cost-effective in an earlier pilot programme adapting these for new contexts and circumstances post Covid-19. Evaluation of the implementation of the out-of-hospital care model programme is currently underway in 17 local authority test sites across England. A specific component of the larger evaluation is aimed at capturing service users’ preferences for different types of specialist hospital discharge schemes.&#x0D; This is done using a flexible health economics tool for measuring choices in health and social care-related settings named discrete choice experiments (DCE). It measures preferences from individual decision-makers over alternative scenarios (or service provisions). Each alternative is described by several attributes (or characteristics) and the choices made between two or more competing scenarios subsequently determine how preferences are influenced by each attribute (eg, which attributes are valued as well as their relative importance). It can also provide a measure of the overall value attached to different alternatives (and identify optimal service provision that meets stakeholder requirements and have the best chance of sustainability in the long term). Hence a DCE survey has been developed to measure people’s preferences for what out-of-hospital care provides in terms of types of location of care, the professional who delivers most of their care, how often they receive care, how long they receive care after hospital discharge and rules about behaviour where they live.&#x0D; The attributes (characteristics) and their various levels were informed by our previous research. Webinar discussions regarding what stakeholders value about specialist services were used to validate and refine the attributes and levels. PPI stakeholders were also consulted on the development of the presentation, wording and format of the survey. Efficient experimental design techniques were applied to create the DCE questions. Due to the cognitive load involved in completing the survey, respondents are assisted in the completion of the questionnaire by members of the research team to secure responses from more than 250 people who are homeless. Data will be modelled using logit techniques and results will be ready for presentation in May 2023.&#x0D; Information on how service users value specialist hospital discharge schemes for people who are homeless is needed to better inform the implementation and development of the innovative out-of-hospital care model programme currently proposed in England at a national level. Identified learning will be shared at the conference.

How important is integration to the successful ‘roll out’ of specialist hospital discharge schemes for people who are homeless?

In 2021, we published research funded by the UK National Institute for Health Research that demonstrated the effectiveness and cost effectiveness of specialist hospital discharge schemes for people who are homeless. A key finding of the research was that areas that had a specialist homeless hospital discharge scheme had fewer delayed discharges and could reduce their emergency readmissions among homeless patients by 14%. This positive outcome attracted the attention of national health policy makers who allocated £16 million funding to 17 local authority areas to “roll out” new schemes. This paper reports the preliminary findings of an implementation evaluation. We assess how important integration was in those areas that successfully translated the evidence about “what works’ into practice. This presentation is targeted at academics and commissioners of integrated care.&#x0D; The evaluation employed a positive deviance (appreciative enquiry) methodology. This approach seeks out exceptionally performing sites, investigates the underlying factors contributing to the successful behaviours and strategies, and plans an appropriate means to replicate these with the aim to effect a change. The rationale behind appreciative inquiry is that solutions to common problems mostly exist within clinical/practice communities rather than externally with policy makers or managers.&#x0D; The first step of the evaluation was to collect audit (performance) data from the 17 local authorities taking part in the programme. Audit data was then used to select three case studies sites that demonstrated high performance against key metrics such as having a shorter length of stay in ‘step-down’ services (longer stays being indicative of housing shortages and difficulties maintaining flow through the system). In the case study sites, reflective interviews and focus groups then sought to establish what factors underpinned this successful implementation. This included interviews with a range of key stakeholders including people with lived experience of homelessness and transitions out-of-hospital (over sixty stakeholders in total).&#x0D; Integration was found to be a key factor in understanding successful implementation at many different levels - from building the initial strategic vision to delivering quality in frontline service delivery. Often this was ‘relational’ integration where building social networks in strategic places was the main factor in determining routinization and sustainability. Often boundary spanning was key where ‘homeless commissioners’ needed to cross the divide into the unfamiliar world of health service commissioning. Relational working required a dedicated project manager with highly developed skills in business planning, evaluation and policy literacy to negotiate the many hurdles that stood in the way of the routinization of specialist care. Successful sites also involved people with lived experience of homeless in meaningful rather than tokenistic activities, integrating their knowledge of services and practice to ensure compassion was at the forefront of practice. Taking an in-depth qualitative perspective on successful implementation is important as very few of the 17 test sites managed to sustain their new services once the initial programme funding had run out.&#x0D;

Why in hospital following transoral robotic lingual tonsillectomy?

Background The reported hospital length of stay (LOS) following transoral robotic surgery lingual tonsillectomy (TORS-L) is variable, with limited understanding of the factors requiring hospitalization and no evidence-based criteria for discharge. Aims/objectives This observational cohort study investigated factors hindering discharge following TORS-L in a well-defined postoperative care program. Methods Patients were included between August 2020 and October 2022. A discharge scheme was filled out twice daily, specifying the factor(s) for hospitalization among patients undergoing TORS-L. This trial was a sub-investigation of a national multicentre randomized clinical trial (RCT) testing the efficiency of high-dose dexamethasone on postoperative pain control. Participation in the RCT demanded admission to the fourth postoperative day as dexamethasone/placebo was given intravenously in repeated dosages till day 4 postoperatively. Results Eighteen patients were included in the analysis. The main factor for hospitalization was nutritional difficulties, while pain was a limiting factor for discharge only on the first postoperative 1-3 days. More than half of the patients could have potentially been discharged on postoperative day 2 when omitting the RCT treatment plan in the analysis. Conclusion The study estimates that the majority of patients may be discharged on postoperative day 2 following TORS-L.

WITHDRAWN: Compréhension du langage médical chez les patients orthopédiques traumatisés des membres inférieurs : une étude d’enquête transversale

IntroductionThe aim of this study was to investigate orthopaedic lower limb trauma patients’ comprehension regarding the affected bone, the surgical implant used, and postoperative instructions, and to evaluate the relationship between sociodemographic features and health literacy. HypothesisThere is a relationship between health literacy levels, the medical awareness of orthopaedic trauma patients and sociodemographic characteristics. Material and methodsThe cross-sectional survey study was conducted from June to September 2021 in the orthopaedic clinic of a level 1 trauma centre. The study group consisted of 225 patients with a surgically treated unilateral lower limb fracture. The questionnaire consisted of 3 parts: (1) sociodemographic information, (2) knowledge about ongoing orthopaedic treatment, and (3) 16-item version of The European Health Literacy Survey (HLS-EU-Q16). ResultsOf the patients in the study, 46% were not aware that they were using thromboembolism prophylaxis, and 10% did not use the prophylaxis. More than half of the patients did not know which bone was fractured, three-quarters did not know what type of implant had been used for the fracture fixation, and approximately 90% of the patients did not know their weight-bearing status and the expected healing time after surgery. Inadequacy of HLS-EU-Q16 score with a median of 34.4, (range: 0–50) was 38.7% (n=87). DiscussionOrthopaedic lower limb trauma patients demonstrated inadequate health literacy with low comprehension of their injuries, surgeries, and discharge schemes. This study's results show the need to promote more effective communication between orthopaedic trauma patients and healthcare providers. Identifying inadequate health literacy in patients and developing appropriate interventions before discharge may help improve outcomes. Level of evidenceII; cross-sectional.

Health literacy in orthopaedic lower limb trauma patients: A cross-sectional survey study

IntroductionThe aim of this study was to investigate orthopaedic lower limb trauma patients’ comprehension regarding the affected bone, the surgical implant used, and postoperative instructions, and to evaluate the relationship between sociodemographic features and health literacy. HypothesisThere is a relationship between health literacy levels, the medical awareness of orthopaedic trauma patients and sociodemographic characteristics. Material and methodsThe cross-sectional survey study was conducted from June to September 2021 in the orthopaedic clinic of a level 1 trauma centre. The study group consisted of 225 patients with a surgically treated unilateral lower limb fracture. The questionnaire consisted of 3 parts: (1) sociodemographic information, (2) knowledge about ongoing orthopaedic treatment, and (3) 16-item version of The European Health Literacy Survey (HLS-EU-Q16). ResultsOf the patients in the study, 46% were not aware that they were using thromboembolism prophylaxis, and 10% did not use the prophylaxis. More than half of the patients did not know which bone was fractured, three-quarters did not know what type of implant had been used for the fracture fixation, and approximately 90% of the patients did not know their weight-bearing status and the expected healing time after surgery. Inadequacy of HLS-EU-Q16 score with a median of 34.4, (range, 0–50) was 38.7% (n=87). DiscussionOrthopaedic lower limb trauma patients demonstrated inadequate health literacy with low comprehension of their injuries, surgeries, and discharge schemes. This study's results show the need to promote more effective communication between orthopaedic trauma patients and healthcare providers. Identifying inadequate health literacy in patients and developing appropriate interventions before discharge may help improve outcomes. Level of evidenceII; cross sectional.

Human-driven long-term disconnect of nutrient inputs to the Yellow River basin and river export to the Bohai Sea

Combining long-term measurements of nitrogen (N) and phosphorus (P) concentrations in the Yellow River (YR) (1981–2018) and river discharge (1981–2018) to the Bohai Sea (BS) with model-based estimates of nutrient delivery shows a disconnect between nutrient delivery and export fluxes to the BS. Basin-wide nutrient delivery to surface water, primarily from agriculture and sewage, exhibited an increasing trend over the whole period. However the nutrient export fluxes to BS declined from 1981 to 2002, followed by a period of large inter-annual variability. Nutrient export is strongly controlled by water discharge, the Water and Sediment Regulation Scheme (WSRS), and the large volume of water containing nutrients that is extracted for primarily irrigation. Dissolved organic N (average 15% in the period 2001–2018) and dissolved organic P (68%) accounted for an important share of total dissolved N and P, which is due to agricultural inputs and preferential retention of inorganic forms in the YR basin. River nutrient export fluxes alone cannot explain the changes in the frequency and area of red tides in the BS due to impacts of the WSRS, the long water residence time in the BS and climate change. This calls for the application of mechanistic models for describing the impact of combined long-term changes in the BS ecosystem.

Classification of Stream, Hyperconcentrated, and Debris Flow Using Dimensional Analysis and Machine Learning

AbstractExtreme rainfall events in mountainous environments usually induce significant sediment runoff or mass movements—debris flows, hyperconcentrated flows and stream flows—that pose substantial threats to human life and infrastructure. However, understanding of the sediment transport mechanisms that control these torrent processes remains incomplete due to the lack of comprehensive field data. This study uses a unique field data set to investigate the characteristics of the transport mechanisms of different channelized sediment‐laden flows. Results confirm that sediments in hyperconcentrated flows and stream flows are mainly supported by viscous shear and turbulent stresses, while grain collisional stresses dominate debris‐flow dynamics. Lahars, a unique sediment transport process in volcanic environments, exhibit a wide range of transport mechanisms similar to those in the three different flow types. Furthermore, the Einstein number (dimensionless sediment flux) exhibits a power‐law relationship with the dimensionless flow discharge. Machine learning is then used to draw boundaries in the Einstein number‐dimensionless discharge scheme to classify one flow from the other and thereby aid in developing appropriate hazard assessments for torrential processes in mountainous and volcanic environments based on measurable hydrologic and geomorphic parameters. The proposed scheme provides a universal criterion that improves existing classification methods that depend solely on the sediment concentration for quantifying the runoff‐to‐debris flow transition relevant to landscape evolution studies and hazard assessments.

An FPGA Charge-to-Digital Converter Based on Voltage-Referenced Receivers for PET Applications

A field programmable gate array (FPGA) voltage-referenced standard receiver based charge-to-digital converter (QDC) was proposed. The QDC is based on a linear discharge scheme. In the linear discharge circuit, typically, a low-voltage differential signaling (LVDS) receiver serves as a voltage comparator. Our proposed scheme takes advantage of voltage-referenced standard in the FPGA instead of the LVDS standard, which maximizes the capability of multichannel and multifunctionality. The linearity differences were compared between the voltage-referenced receivers and the LVDS receiver. To validate the scheme for radiation detector application, a 32-channel electronics prototype based on the proposed structure was developed. A positron emission tomography (PET) detector module was built. The detector is made up of a 15 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times $ </tex-math></inline-formula> 15 LYSO array directly coupled with two silicon photomultipliers (SiPM) at two ends. The mean energy resolution for single crystal at the center can reach 17.9%. The linear discharge scheme based on voltage-referenced receivers provides a promising method for a compact, multichannel electronics readout system for radiation detector application.

Proactive care post-discharge to reduce 30 day readmissions to hospital.

Healthwatch England estimated emergency readmissions have risen by 22.8% between 2012-13 and 2016-17. Some emergency readmissions could be avoided by providing patients with urgent out of hospital medical care or support. Sovereign Health Network (SHN) comprises of three GP practices, with a combined population of 38,000. We will decrease the number of SHN patients readmitted within 30 days of discharge from Portsmouth Hospitals Trust following a non-elective admission (excluding Emergency Department attendance) by 40-60% by July 2020. Four Plan, Do, Study, Act (PDSA) cycles were used to test the administrative and clinical processes. Our Advanced Nurse Practitioner reviewed all discharge summaries, added alerts to records, and proactively contacted patients either by text, telephone or home visit. 92 patients aged 23 days to 97 years were admitted onto the recent discharge scheme. Half of discharge summaries were received on the day of discharge, whilst 29% of discharge summaries were received more than 24 hours post-discharge, and one was received 11 days post-discharge. Following our interventions, there were 55% less than expected readmissions during the same time period. To allow proactive interventions to be instigated in a timely manner, discharge summaries need to be received promptly. The average readmission length of stay following a non-elective admission is seven days. Our proactive interventions saved approximately 102.9 bed days, with potential savings of 1,775 bed days over a year. We feel the results from our model are promising and could be replicated by other Primary Care Networks to result in larger savings in bed days.

Hazard assessment and prediction of ice-jam flooding for a river regulated by reservoirs using an integrated probabilistic modelling approach

To effectively alleviate ice-jam flood disasters, it is necessary to carry out hazard assessments and predictions of ice-jam flooding influenced by the operational scheme of a reservoir. However, traditional hydrologic flood routing techniques cannot effectively address the huge uncertainties caused by the many factors that lead to ice-jam flooding. In this paper, a hazard assessment system for regulating flood discharge schemes is developed; it is composed of a machine learning (ML) model, Long Short-Term Memory (LSTM), and a river-ice dynamic model (RIVICE) within a probabilistic method. The modelling system is to aid in the challenge of predicting ice-jam flooding downstream of reservoirs. The LSTM model forecasts the downstream flow under the operational discharge scheme and, combined with the RIVICE model, the backwater level profile of ice jams can be forecasted. Furthermore, a set of backwater level profiles can be provided by probabilistic modelling, and the probability of ice-jam flood inundation can be calculated by comparing backwater levels with the elevation of the river bank; this information can be used to warn of the hazard induced by operational discharges to better aid in the preparedness and mitigation of ice-jam floods. This system was tested successfully for the ice-cover breakup period in the spring of 2008 and 2018 along the Sanhuhekou bend reach of the Yellow River in China.

Effects of the Long-Term Climate Change and Selective Discharge Schemes on the Thermal Stratification of a Large Deep Reservoir, Xin’anjiang Reservoir, China

The effects of global warming and precipitation changes on water temperature and thermocline parameters, such as thermocline depth, thickness, and strength, were assessed. A catchment model, coupled with a reservoir thermal model with meteorological input calculated by a downscaled general circulation model (GCM) projection under three representative concentration pathways (RCPs), was applied to the Xin’anjiang Reservoir, located in southeast China. The results indicate that water temperature in each layer increased (decreased) with the rise (decline) in air temperature, especially the surface water temperature. There was a significant negative (positive) correlation between thermocline depth (strength) and air temperature during the period of stratification weakness. The most sensitive phenomenon of water temperature-to-precipitation changes occurred in the middle layer (depth = 30 m). Additionally, the thermocline depth and thickness increased with decreases in hydraulic residence time, which were caused by precipitation increases. According to the simulation experiments driven by RCP outputs, mean water temperature in each water layer in the future (2096–2100) has a strong response to increases in air temperature, which is projected to increase by 0.11–0.62 °C for RCP2.6, 0.76–1.19 °C for RCP4.5, and 1.50–2.35 °C for RCP8.5, compared to the baseline (2012–2016). However, mean water temperature in each water layer from 2096 to 2100 underwent a slight decrease caused by precipitation changes, with a 0.03–0.25 °C decrease for RCP2.6, 0.07–0.40 °C for RCP4.5, and 0.04–0.29 °C for RCP8.5, compared to 2012–2016. The mean thermocline depth in the future (2096–2100) will be significantly decreased, while the mean thermocline thickness will be slightly increased. Over a multiyear timescale, the impacts of air temperature changes are stronger than those induced by precipitation variations. However, the effects of hydraulic residence time changes caused by precipitation changes (especially rainstorm) should be considered in the management of deep reservoirs.

Evaluation of Lightning Prediction by an Electrification and Discharge Model in Long-Term Forecasting Experiments

Over nearly three rainy seasons of lightning activity in North China, numerical prediction experiments were carried out using the Weather Research and Forecasting model coupled with electrification and discharge schemes (WRF-Electric). The numerical forecast results were evaluated using the neighborhood-based equitable threat score (ETS) and fraction skill score (FSS) verification methods based on nationwide observational lightning data. An algorithm was used to generate the coverage of the total flash (intracloud and cloud-to-ground flashes) by fitting the cloud-to-ground flash data. The numerical results showed that the region of lightning activity could be well predicted by the mesoscale WRF-Electric model, particularly during a 6–12-hour forecasting period. The average ETS score of the 6–12-hour forecasting period was 0.34 for a 20 km neighborhood radius. The predictive skill of the model varied not only monthly but also diurnally. The model showed better forecasting skills during the main rainy season (June–July–August) and at 14 : 00–20 : 00 local time. The predictability of the model was enhanced with increasing thunderstorm scale. On the other hand, the coverage of predicted lightning activity was relatively concentrated, and the lightning flash density was higher than the observations. The main discrepancies in the model prediction were related to the design of the discharge parameterization. Thus, in discharge parameterization, the initial threshold for lightning should be modified according to the model resolution, while the magnitude of the neutralization charge in a single discharge should be referenced to the observational results.

Southern Ocean polynyas in CMIP6 models

Abstract. Polynyas facilitate air–sea fluxes, impacting climate-relevant properties such as sea ice formation and deep water production. Despite their importance, polynyas have been poorly represented in past generations of climate models. Here we present a method to track the presence, frequency and spatial distribution of polynyas in the Southern Ocean in 27 models participating in the Climate Model Intercomparison Project Phase 6 (CMIP6) and two satellite-based sea ice products. Only half of the 27 models form open-water polynyas (OWPs), and most underestimate their area. As in satellite observations, three models show episodes of high OWP activity separated by decades of no OWP, while other models unrealistically create OWPs nearly every year. In contrast, the coastal polynya area is overestimated in most models, with the least accurate representations occurring in the models with the coarsest horizontal resolution. We show that the presence or absence of OWPs is linked to changes in the regional hydrography, specifically the linkages between polynya activity with deep water convection and/or the shoaling of the upper water column thermocline. Models with an accurate Antarctic Circumpolar Current transport and wind stress curl have too frequent OWPs. Biases in polynya representation continue to exist in climate models, which has an impact on the regional ocean circulation and ventilation that should be addressed. However, emerging iceberg discharge schemes, more adequate vertical grid type or overflow parameterisation are anticipated to improve polynya representations and associated climate prediction in the future.

Improving care transfers for homeless patients after hospital discharge: a realist evaluation

Background In 2013, 70% of people who were homeless on admission to hospital were discharged back to the street without having their care and support needs addressed. In response, the UK government provided funding for 52 new specialist homeless hospital discharge schemes. This study employed RAMESES II (Realist And Meta-narrative Evidence Syntheses: Evolving Standards) guidelines between September 2015 and 2019 to undertake a realist evaluation to establish what worked, for whom, under what circumstances and why. It was hypothesised that delivering outcomes linked to consistently safe, timely care transfers for homeless patients would depend on hospital discharge schemes implementing a series of high-impact changes (resource mechanisms). These changes encompassed multidisciplinary discharge co-ordination (delivered through clinically led homeless teams) and ‘step-down’ intermediate care. These facilitated time-limited care and support and alternative pathways out of hospital for people who could not go straight home. Methods The realist hypothesis was tested empirically and refined through three work packages. Work package 1 generated seven qualitative case studies, comparing sites with different types of specialist homeless hospital discharge schemes (n = 5) and those with no specialist discharge scheme (standard care) (n = 2). Methods of data collection included interviews with 77 practitioners and stakeholders and 70 people who were homeless on admission to hospital. A ‘data linkage’ process (work package 2) and an economic evaluation (work package 3) were also undertaken. The data linkage process resulted in data being collected on &gt; 3882 patients from 17 discharge schemes across England. The study involved people with lived experience of homelessness in all stages. Results There was strong evidence to support our realist hypothesis. Specialist homeless hospital discharge schemes employing multidisciplinary discharge co-ordination and ‘step-down’ intermediate care were more effective and cost-effective than standard care. Specialist care was shown to reduce delayed transfers of care. Accident and emergency visits were also 18% lower among homeless patients discharged at a site with a step-down service than at those without. However, there was an impact on the effectiveness of the schemes when they were underfunded or when there was a shortage of permanent supportive housing and longer-term care and support. In these contexts, it remained (tacitly) accepted practice (across both standard and specialist care sites) to discharge homeless patients to the streets, rather than delay their transfer. We found little evidence that discharge schemes fired a change in reasoning with regard to the cultural distance that positions ‘homeless patients’ as somehow less vulnerable than other groups of patients. We refined our hypothesis to reflect that high-impact changes need to be underpinned by robust adult safeguarding. Strengths and limitations To our knowledge, this is the largest study of the outcomes of homeless patients discharged from hospital in the UK. Owing to issues with the comparator group, the effectiveness analysis undertaken for the data linkage was limited to comparisons of different types of specialist discharge scheme (rather than specialist vs. standard care). Future work There is a need to consider approaches that align with those for value or alliance-based commissioning where the evaluative gaze is shifted from discrete interventions to understanding how the system is working as a whole to deliver outcomes for a defined patient population. Funding This project was funded by the National Institute for Health Research (NIHR) Health Services and Delivery Research programme and will be published in full in Health Services and Delivery Research; Vol. 9, No. 17. See the NIHR Journals Library website for further project information.