Potential Savings Research Articles

Energy Efficiency in Seasonal Homes: A Study on the Occupancy, Energy Use, and Renovation of Second Homes in Sweden

The escalating utilisation of second homes has led to an extension in heating periods and, to a certain degree, renovations to elevate the standard, resulting in augmented energy and resource consumption. A comprehensive survey was conducted in Sweden, examining user patterns across different seasons, heating systems, and implemented energy efficiency measures. The results indicate that second homes are occupied for extended periods during the summer season and intermittently throughout the year. Over half of the second homes are heated even when unoccupied, with 12% maintaining a temperature above 16 °C. The predominant heating method is direct electricity (32.2%), followed by heat pumps (29.5%) and stoves (17.5%). A variety of renovations are undertaken, primarily to enhance the standard and technical performance, but also to implement energy efficiency measures such as window replacement, additional insulation, or heat pump installation. Based on the reported user and heating patterns, and the energy renovations carried out, the potential energy savings with different energy renovation strategies were estimated for the Swedish second home stock. The results show that though lowering the temperature when a second home is unoccupied emerges as the most efficient measure, both in terms of cost-effectiveness and climate impact, it needs to be complemented with intermittent heating or dehumidification to ensure that the relative humidity is below critical levels, to avoid the risk of damages caused by, for example, mould growth. Installing a heat pump is the second most energy- and cost-effective measure and has the advantage that the indoor temperature can be maintained at rather high levels.

Extended end-of-life carbon assessment and savings: A case study of steel-framed modular buildings in Hong Kong

Modular construction (MC) advances conventional approaches such as material efficiency, shorter construction time, and reduced onsite waste, leading to lower carbon emissions in some stages. However, the End-of-Life (EoL) carbon has never been made explicit, particularly for MC, and there remains a lack of evidence on how much carbon emissions are generated and reduced from the EoL stage of modular buildings. To address the gaps, the present study proposes an EoL carbon estimation model for MC based on the life cycle assessment (LCA) method. The developed model was empirically validated through a case study of a typical high-rise steel-framed modular residential building in Hong Kong. The results reveal that net carbon emissions during the EoL stage could be −764.40 kg CO2 eq./m2, presenting the great carbon savings potential of MC. Compared to those in traditional on-site construction areas, steel modular components have far greater capabilities to mitigate carbon emissions, as most of them can be reused. Nevertheless, an average of 41.56 kg CO2 eq./m2 of carbon is still released in the EoL stage, most of which is contributed by transportation, followed by waste disposal, demolition, and waste processing. This study makes an original contribution to understanding the extent of EoL carbon emissions and the potential of carbon savings in steel modular buildings. Also, these findings unveil the practical significance of reusing modules for EoL carbon mitigation and provide useful suggestions for demolition contractors and policymakers to mitigate carbon emissions to further promote the transition towards carbon neutrality.

Letter to the editor: Prospective analysis of STRATAFIX™ symmetric PDS plus suture for fascial closure in spinal surgery: a pilot study.

Spine surgery is essential for restoring alignment, stability, and function in patients with cervical spine injuries, especially when instability, pain, deformity, or progressive nerve damage is present. Effective wound closure is vital in these procedures, aiming to promote rapid healing, reduce infection risks, enable early mobilization, and ensure satisfactory cosmetic results. However, there is limited evidence on the optimal wound closure technique for posterior spine surgery, highlighting the need for innovative approaches. A study by Glener et al. evaluated the effectiveness of STRATAFIX™ Symmetric barbed sutures compared to traditional braided absorbable sutures in spinal surgery. In a randomized trial involving 20 patients, the STRATAFIX™ group demonstrated a shorter mean closure time and significantly fewer sutures used, though without a statistically significant reduction in closure time. No significant differences were observed in postoperative complications between the groups during a six-month follow-up. While the findings suggest potential cost savings and efficiency improvements with STRATAFIX™, the study's small sample size and short follow-up period limit its generalizability. Furthermore, AI-based models, such as the Xception deep learning model, show promise in improving suture training accuracy for medical students, which could enhance surgical outcomes and reduce complications. Despite the promising results, further research with larger sample sizes, extended follow-up periods, and multi-center trials is necessary to validate the effectiveness of barbed sutures like STRATAFIX™ in neurosurgery. The integration of AI in surgical training and continued exploration of innovative techniques are essential to advancing the field and optimizing patient care in spinal surgery.

Implementation of Artificial Intelligence-Based Diabetic Retinopathy Screening in a Tertiary Care Hospital in Quebec: Prospective Validation Study.

Diabetic retinopathy (DR) affects about 25% of people with diabetes in Canada. Early detection of DR is essential for preventing vision loss. We evaluated the real-world performance of an artificial intelligence (AI) system that analyzes fundus images for DR screening in a Quebec tertiary care center. We prospectively recruited adult patients with diabetes at the Centre hospitalier de l'Université de Montréal (CHUM) in Montreal, Quebec, Canada. Patients underwent dual-pathway screening: first by the Computer Assisted Retinal Analysis (CARA) AI system (index test), then by standard ophthalmological examination (reference standard). We measured the AI system's sensitivity and specificity for detecting referable disease at the patient level, along with its performance for detecting any retinopathy and diabetic macular edema (DME) at the eye level, and potential cost savings. This study included 115 patients. CARA demonstrated a sensitivity of 87.5% (95% CI 71.9-95.0) and specificity of 66.2% (95% CI 54.3-76.3) for detecting referable disease at the patient level. For any retinopathy detection at the eye level, CARA showed 88.2% sensitivity (95% CI 76.6-94.5) and 71.4% specificity (95% CI 63.7-78.1). For DME detection, CARA had 100% sensitivity (95% CI 64.6-100) and 81.9% specificity (95% CI 75.6-86.8). Potential yearly savings from implementing CARA at the CHUM were estimated at CAD $245,635 (US $177,643.23, as of July 26, 2024) considering 5000 patients with diabetes. Our study indicates that integrating a semiautomated AI system for DR screening demonstrates high sensitivity for detecting referable disease in a real-world setting. This system has the potential to improve screening efficiency and reduce costs at the CHUM, but more work is needed to validate it.

Quantitative Monitoring Maximizes Cost-Saving Strategies When Antagonizing Neuromuscular Block With Sugammadex.

Introduction Weight-based dosing combined with variable patient weights in pediatric anesthesia can lead to significant medication excess and waste from single-use medication vials packaged for dosing in adults. Medication aliquots have been proposed as a strategy to decrease waste and therefore expense when using high-cost medications such as sugammadex. Appropriate dosing of sugammadex to antagonize neuromuscular block is based on the results of quantitative monitoring, though the use of these monitors is not routine. In this quality improvement project, we demonstrate cost savings from aliquoting sugammadex from large, single-use vials and using quantitative monitoring to guide accurate and appropriate dosing. Methods After institutional review and approval, patients receiving rocuronium neuromuscular block during their anesthetic care between October 10 and December 9, 2022, were included for analysis. Sugammadex aliquots were prepared under sterile conditions in the operating room pharmacy according to current compounding guidelines. Quantitative neuromuscular monitoring with electromyography-based monitors was used to guide accurate sugammadex dosing. Cost analysis included the actual savings achieved when aliquots were used instead of single-use vials, the potential savings if aliquots had been used as opposed to single-use vials, and the actual savings achieved when quantitative monitoring indicated that adequate spontaneous recovery was reached and sugammadex administration was not needed. Results A total of 200 patients were included in the analysis. In 73 patients, a 200 mg/2 ml vial of sugammadex was utilized, while 86 patients received sugammadex from pre-filled aliquot syringes of 50 mg/0.5 ml. Forty-one patients did not require sugammadex antagonism as they achieved spontaneous recovery to a train-of-four ratio ≥90%. Conclusion Administration of sugammadex from aliquots rather than manufacturer-packaged single-use vials, with dosing guided by quantitative neuromuscular monitoring, produced a net cost savings of approximately $46 per case and projected net annual cost savings of nearly $370,000 in our institution. Forty percent of the net cost savings came from confirmation by quantitative monitoring of adequate spontaneous recovery to a train-of-four ratio ≥90%.

Enhancing light absorption in ultra-thin perovskite solar cells using plasmonic gold nanoparticle clusters

Perovskite solar cells with ultra-thin absorber layers offer potential cost savings in manufacturing, but their reduced thickness can limit light absorption and efficiency. This work explores using plasmonic gold nanoparticles as a light-trapping strategy to compensate for lower absorption in ultra-thin perovskite devices. Numerical simulations investigate embedding 25 nm radius gold nanoparticles within the 200 nm thick perovskite active layer to boost optical absorption through near-field enhancement and light scattering effects. The solar cell structure incorporating these plasmonic nanoparticles achieves a substantially higher short-circuit current density of 23.10 mA cm−2 compared to 18.70 mA cm−2 for a reference cell without nanoparticles. This study provides design approaches for realizing high-efficiency yet cost-effective ultra-thin perovskite photovoltaics by harnessing plasmonic light-trapping techniques. The results display methodologies to improve photon absorption and power conversion in thin-film perovskite devices through strategic nanoparticle integration.

Economic impact of limb-salvage strategies in chronic limb-threatening ischaemia: modelling and budget impact study based on national registry data.

Missed opportunities to reduce numbers of primary major lower-limb amputation and increase limb-salvage procedures when treating chronic limb-threatening ischaemia have previously been identified in the literature. However, the potential economic savings for healthcare providers when salvaging a chronic limb-threatening ischaemia-affected limb have not been well documented. A model using National Health Service healthcare usage and cost data for 1.6 million individuals and averaged numbers of primary surgical procedures for chronic limb-threatening ischaemia from England and Wales in 2019-2021 was created to perform a budget impact analysis. Two scenarios were tested: the averaged national rates of major lower-limb amputation (above the ankle joint), angioplasty, open bypass surgery or arterial endarterectomy in the National Vascular Registry (current scenario); and revascularization rates adjusted based on the lowest amputation rate reported by the National Vascular Registry at the time of the study (hypothetical scenario). The primary outcome was the net impact on costs to the National Health Service over 12 months after the index procedure. In the current scenario, the proportions of different index procedures were 10% for lower-limb major amputation, 55% for angioplasty, 25% for open bypass surgery and 10% for arterial endarterectomy. In the hypothetical scenario, the procedure rates were 3% for major lower-limb amputation, 59% for angioplasty, 27% for open bypass surgery and 11% for arterial endarterectomy. For 16 025 index chronic limb-threatening ischaemia procedures, the total care cost in the current scenario was €243 924 927. In the hypothetical scenario, costs would be reduced for index procedures (-€10 013 814), community care (-€633 943) and major cardiovascular events (-€383 407), and increased for primary care (€59 827), outpatient appointments (€120 050) and subsequent chronic limb-threatening ischaemia-related surgery (€1 179 107). The net saving to the National Health Service would be €9 645 259. A shift away from primary major lower-limb amputation towards revascularization could lead to substantial savings for the National Health Service without major cost increases later in the care pathway, indicating that care decisions taken in hospitals have wider benefits.

Modeling the output from a commercial chemical process using regression models from survival analysis

This article is concerned with the modeling of the gas output of a commercial chemical plant using the coal sources as predictor variables. We consider the use of two models to incorporate these predictors; the Cox proportional hazards and accelerated failure time regression models. These models are chosen for their simplicity and for the ease with which the effects of explanatory variables can be interpreted. The contribution of this article lies therein that these models are used in the current context for the first time. We show, using both graphical and formal hypothesis testing procedures that these models (with a Weibull baseline distribution) fit observed gas production data well. We provide a discussion of the interpretation of the estimated model parameters and we comment on how these estimates can be of substantial practical value. The large scale of production from the chemical plant in question ensures that potential cost savings and increases in production associated with more accurate models are of great practical importance.

From CFOs to crypto: exploratory study unraveling factors in corporate adoption

Cryptocurrency adoption has gained significant attention across various fields owing to its disruptive potential and associated challenges. However, companies' adoption of cryptocurrencies remains relatively low. This study aims to comprehensively examine the factors influencing cryptocurrency adoption, their interrelationships, and their relative importance. To achieve this objective, we employ a Decision-Making Trial and Evaluation Laboratory (DEMATEL) approach coupled with network analysis tools. By adopting a practical approach rather than a purely theoretical one, our unique contribution lies in the valuable insights derived from experienced Chief Financial Officers (CFOs) of various companies with experience in both traditional finance and cryptocurrencies. Furthermore, the unique blend of analytical rigor and industry expertise supports the study's relevance, offering nuanced insights that are not only academically robust but also immediately applicable in the corporate landscape. Our findings highlight the paramount importance of safety in transactions and trust in the chosen platform for companies considering cryptocurrency adoption. Additionally, criteria such as faster transactions without geographical limitations, lower transaction fees, seamless integration with existing systems, and potential cost savings are identified as crucial drivers. Both the DEMATEL approach and network analysis reveal strong interconnections among the criteria, emphasizing their interdependence and, notably, their reliance on transactional safety. Furthermore, our causes and effects analysis indicates that CFOs perceive company-led cryptocurrency adoption to positively impact the broader cryptocurrency market.

A cost-consequence analysis of the Queensland specialist palliative rural telehealth (SPaRTa) service

Background Telehealth can extend the reach of specialist palliative care providers to ensure that patients can access specialist services closer to home. Aim To examine the cost and consequences of the Specialist Palliative Rural Telehealth (SPaRTa) service compared to the traditional non-specialist general practice-based services for people requiring palliative care. Design The costs and outcomes for SPaRTa were compared using cost-consequence analysis principles, with a focus on net benefit and return on investment. Costs were estimated from the perspective of the health service provider for the 2020/2021 financial year, and cost-offsets associated with change in location of death and change in hospital transfers. Setting/participants Patients of the SPaRTa in Queensland Australia. Results During study period 5472 consultations were conducted from four major metropolitan hub sites to regional, rural, and remote areas at a total cost of $4 426 644. When remuneration for consultations, change to location of death and reduction in ambulance transfers were taken into account, the net-benefit to the state health system was $1 244 060, giving a return on investment of $1.28 for every dollar spent. SPaRTa complimented existing local care services, and enabled access to specialist care into the home. Conclusions SPaRTa resulted in potential cost savings for the health service by enabling more convenient access to palliative care services outside of hospital settings. Decisions regarding funding for telepalliative care should consider not only the costs, but also the potential benefits to both the service providers, and the patients and families receiving this care.

The Use of Clips to Prevent Post-Polypectomy Bleeding: A Clinical Review.

The goal of this clinical review is to provide an overview of the current literature regarding the utility of prophylactic clips in reducing postpolypectomy bleeding and to provide an expert statement regarding their appropriateness in clinical practice. Colonoscopy enables the identification and removal of premalignant and malignant lesions through polypectomy, yet complications including postpolypectomy bleeding (PPB) can arise. While various studies have explored applying clips prophylactically to prevent PPB, their effectiveness remains uncertain. A literature search conducted in PubMed and Embase identified 671 publications discussing clip use postpolypectomy; 67 were found to be relevant after screening, reporting outcomes related to PPB. Data related to clip utilization, polyp characteristics, and adverse events were extracted and discussed. The current literature suggests that prophylactic clipping is most beneficial for nonpedunculated polyps ≥20mm, especially those in the proximal colon. The utility of clipping smaller polyps and those in the distal colon remains less clear. Antithrombotic medication usage, particularly anticoagulants, has been linked to an increased risk of bleeding, prompting consideration for clip placement in this patient subgroup. While cost-effectiveness analyses may indicate potential savings, the decision to clip should be tailored to individual patient factors and polyp characteristics. Current research suggests that the application of prophylactic clips can be particularly beneficial in preventing delayed bleeding after removal of large nonpedunculated polyps, especially for those in the proximal colon and in patients on antithrombotic medications. In addition, for large pedunculated polyps prophylactic clipping is most effective at controlling immediate bleeding.

Holistic life cycle cost analysis of road bridges with non-metallic reinforcement

Corrosion-related damage due to exposure to environmental conditions is the main cause of costs in the maintenance of transport infrastructure. Because of its high corrosion resistance and the associated higher durability, non-metallic reinforcement offers great potential for preventing such damage, thus reducing maintenance costs. In this article, potential savings for an integral road bridge are studied through a holistic life cycle cost (LCC) analysis considering four different reinforcement materials (steel, glass, basalt, carbon). A fair comparison is enabled by a material-specific design, the calculation of maintenance and user costs and the consideration of the respective disposal scenario. Moreover, environmental costs are recognised by carbon pricing based on life cycle analysis (LCA). The influence of individual parameters is quantified by means of a sensitivity analysis and the probability of savings is studied by Monte Carlo simulation. It is shown that higher investment costs for non-metallic reinforcement can be compensated by lower user costs. This is mainly due to shorter maintenance periods, as less time is required for repair action, whereby potential savings in user costs are particularly evident if the traffic route below the bridge is not disrupted. It is concluded that even from today's perspective, the use of glass and basalt fibre-reinforced polymer (FRP) reinforcement in highway bridges with average traffic volumes very likely offers an economic advantage over corrosion-prone reinforcing steel.

Enhance Power Generation of PV Array under Partial Shading Conditions by a Lo Shu and Optimal SuDoKu Puzzle Fusion Topology

A novel Lo Shu and Optimal SuDoKu Puzzle Fusion Topology (LS-OSDKP) is presented to disperse shading effects and enhance photovoltaic (PV) array output power under partial shading conditions (PSCs). Incorporating the ancient Chinese Lo Shu magic square puzzle and the Optimal SDKP topologies, the proposed LS-OSDKP is capable of alleviating current mismatch losses, decreasing wiring loss, simplifying the P-V curves of the array, and significantly improving shading dispersion. Under six PSCs, the performance of the proposed topology was evaluated using a 9 × 9 PV array and compared to the total-cross-tied (TCT), Twisted Two-Step, SDKP, Optimal SDKP, and Lo Shu topologies. Simulation results confirmed that the proposed method could extract the highest averaged power of the PV array among the six topologies, with a 10.47% power improvement when compared to the TCT. Additionally, the LS-OSDKP is capable of effectively reducing the wiring length by 29.09% compared to the Lo Shu. Moreover, the proposed method has the highest potential for energy savings and revenue generation. Compared to the conventional TCT configuration, it could improve extracted energy by approximately 9.58% and shorten payback time by approximately 9.06%. Consequently, the advantages of the proposed LS-OSDKP topology include an increase in extracted power, a reduction in wiring loss, and a shorter energy payback period.

Economic and environmental assessment of the Korea urban railway and its greenhouse gas mitigation potential

Railways can simultaneously transport large quantities of freight and passengers, making them energy-efficient and economical modes of transportation. Changing the materials that constitute a significant portion of rail track systems can help mitigate climate change. Gravel and concrete trackbed methods are commonly employed in railway construction. This study proposes the utilization of the asphalt concrete trackbed method, which is currently being researched and developed in South Korea, in addition to traditional gravel and cement concrete methods, and presents its economic feasibility and environmental benefits. The asphalt concrete trackbed method, which has already been implemented in regions such as China, Australia, and Europe, can also be applied in other areas. This study analyzed the carbon emissions and economic feasibility in the construction, usage, and disposal stages of cement concrete and asphalt concrete trackbeds. Previous research on carbon emissions analysis has faced challenges in applying geographical and climatic, as well as energy sources, to individual cases in the context of construction in Korea. Using the Korean Life Cycle Inventory database, this study indicated that asphalt concrete exhibits approximately 2.65-times lower carbon emissions than cement concrete. In Korea, railway construction involves 1,998 tons of asphalt concrete mixture, 1,820 cubic meters of cement concrete, and 59 tons of rebar per kilometer. Furthermore, the asphalt concrete trackbed method shows potential cost savings of approximately 29,000 EUR when converted to the 2021 EAU value. Thus, asphalt concrete trackbeds not only provide environmental benefits, they are also economically viable. However, further research is required to establish precise standards for on-site construction. This study is expected to provide foundational data for promoting the widespread adoption of asphalt concrete trackbeds in areas that produce asphalt concrete.

A single-centre retrospective study of the utility of routine chest X-ray post intrathoracic drain removal in cardiothoracic surgical patients.

Routine chest X-ray (CXR) post intrathoracic drain removal in cardiac surgical patients is common practice to identify the presence of a pneumothorax following drain removal. Such pneumothoraces occur infrequently and rarely require intervention. We investigated the utility of routine CXR post drain removal and hypothesised that the practice is unnecessary and a possible area for significant cost saving. We conducted a single-centre, retrospective study of 390 patients who underwent cardiac surgery over a one-year period. Routine CXR post drain removal was reviewed for the presence of a pneumothorax. Rates of intervention post routine CXR were analysed to assess for clinical benefit obtained from this practice. Potential cost savings were calculated by the cost of a mobile CXR and by considering the radiographer's time. There were 15 pneumothoraces detected on routine CXR post drain removal. All pneumothoraces detected on routine post drain removal CXR were defined as small. No patients had a clinically significant pneumothorax requiring re-insertion of a chest drain. The potential cost saved by omitting routine CXR post drain removal was estimated to be approximately A$7750 per year. This study did not detect any clinically significant pneumothoraces requiring intervention. It also suggests that routine CXR post drain removal does not provide any clinical benefit and indicates that current practice should be reviewed.

The Relative Timing, Outcomes, and Economic Impact of Anti-Nuclear Antibody (ANA) and Extractable Nuclear Antigen (ENA) Laboratory Ordering.

Objective: To determine the rates of simultaneous antinuclear antibodies (ANA) screening and extractable nuclear antigen (ENA) testing that do not follow recommendations.Design, Setting, and Participants: Retrospective cohort study of adult patients (≥18 years) with a HEp-2 ANA or ENA ordered in the Marshfield Clinic Health System.Main Outcome(s) and Measure(s): Counts of patients having simultaneous ANA and ENA laboratory testing or ENA testing without ANA screening. Relevant ENA positivity in ANA negative patients. Secondary measures included relative timing of ANA and ENA ordering, potential cost savings of unnecessary testing, and provider ordering characteristics including specialty and provider type.Results: Of 58,627 cohort patients, 39,155 (66.8%) were women, and the mean (SD) age at first laboratory testing was 48.7 (19.0) years. The negative ANA with positive ENA rate was 2%. Further stratification identified only 23 diagnosed autoimmune connective tissue diseases (AI-CTDs) in this 2%, with a resulting negative ANA with relevant positive ENA rate of 0.37%. Simultaneous ANA and ENA testing occurred in 8.3% of patients, and an ENA only was ordered in 24.2% of patients. The simultaneous or non-sequential ordering of ANA and ENA testing resulted in significant health care costs of $2,293,251.80 over 20,112 unique patients.Conclusions and Relevance: A significant percentage of providers do not follow recommendations to sequentially order ANA and ENA testing on patients with suspected AI-CTDs. Significant saving in health care spending without failure to diagnose AI-CTDs can be achieved if ANA testing is performed first, followed by ENA testing when suspecting AI-CTDs in patients.

Comparing 0.05% chlorhexidine gluconate monotherapy to conventional antibiotic irrigation in de-novo penile prosthesis implantation: a two-center prospective randomized controlled non-inferiority study (preliminary results).

Infection remains a significant concern following penile prosthesis (PP) implantation surgery. Published guidelines have indicated the use of pre-operative intravenous (IV) antibiotics but have not provided specific recommendations regarding intra-operative irrigation. For long in our practice, we have been using a combination of antibiotics for irrigation (rifampin 600 mg/L of sterile water, gentamicin 80 mg/L of sterile water). Recently, 0.05% chlorhexidine gluconate (CHG) (Irrisept®) (Irrimax Corp, Lawrenceville, GA, USA), has shown promise as an alternative irrigant, with potential advantages in terms of cost, ease of administration and reduced antibiotic resistance risk. The study aims to assess the non-inferiority of CHG antiseptic irrigation compared to conventional combined antibiotic irrigation in preventing postoperative infections for men undergoing de-novo PP implantation. This is a two-center Institutional Review Board (IRB) approved prospective randomized controlled non inferiority trial, involving men undergoing de-novo PP implantation with a predetermined non-inferiority margin of 4%. Patients were randomly assigned into one of two groups: the CHG irrigation or the group receiving conventional antibiotic irrigation. All patients received IV antibiotics preoperatively and were sent home on oral antibiotics for 2 weeks post-operatively. The primary endpoint of this trial was to evaluate the incidence of PP infections. Secondary objectives encompassed the assessment of simplicity of use and cost-effectiveness. A hundred patients were enrolled in our study so far (50 in each arm). Only one case of PP infection necessitating explanation was reported in each arm. Moreover, the use of CHG irrigation offered the potential advantages of ease of administration and less cost as compared to antibiotic irrigation solutions. Preliminary data from this non-inferiority study demonstrate that CHG irrigation is non-inferior to conventional antibiotic irrigation in preventing postoperative infection following PP implantation. These findings support the consideration of CHG irrigation as a viable alternative during PP implantation, offering both clinical effectiveness and potential cost savings as well as reducing the risk of antibiotic resistance. ClinicalTrials.gov NCT06489431.

Rule-based energy management strategies for PEMFC-based micro-CHP systems: A comparative analysis

Commercial PEMFC-based micro-CHP systems are operated by rule-based energy management strategies. Each of these strategies constitutes a different way to meet the household energy demand (following the heat demand, following the electricity demand, the maximum of the two, etc.). Previous studies demonstrate that which of them is the best —i.e. the one that manages to meet the demand at the lowest operating cost— depends on the particular scenario in which the micro-CHP system works (gas and electricity prices, annual energy demands, ability to export electricity to the grid, etc.). This paper aims to explore this dependence relationship and to deepen our understanding of it. To this end, a parametric analysis is conducted and the performances achieved by four rule-based operating strategies are compared. The parameters whose influence is studied, and through which the scenario is jointly characterized, are: (1) energy prices (electricity and natural gas), (2) feed-in tariff, (3) stack degradation, (4) climate and (5) heat to power ratio of the demand. The results show this dependence relationship in a clear and more comprehensive way, and offer a better understanding of its nature. From this improved understanding it can be inferred, among other things, that adapting the strategy to the scenario can generate annual savings of up to 14.5 percentage points. Moreover, this enhanced characterization of that dependence relationship can be useful for the design of a new operating strategy, a strategy that, without falling into the complexity that an optimal energy management approach (based on linear programming) involves, manages to exploit the savings potential of micro-CHP systems, thus facilitating their future mass commercialization.

Climate change mitigation and adaptation in Spanish office stock through cool roofs

In a context of climate change, the cooling period of buildings is increasing every year in Mediterranean countries. This will become a relevant issue when existing buildings are retrofitted. Cool roofs have a passive cooling effect on a building and can contribute to decreasing the annual cooling demand. In office buildings, thermal comfort has a considerable influence on workers’ performance. In these buildings cooling energy demands tend to be high due to the high internal thermal loads. This paper describes annual energy simulations of Spanish office stock to evaluate the potential energy savings of cool roofs within the context of building retrofitting. The energy demand and thermal comfort of representative office buildings is compared before and after the application of a cool roof coating, in the present time and in the year 2050, for all climate areas of Spain, under the most optimistic and most pessimistic future weather scenarios. Results showed that the cooling energy demand of Spanish office stock can be potentially reduced by 25 % when a cool roof is applied, and the annual energy demand for heating and cooling can be cut by 6 %, 11 % and 12 % in the present, the optimistic future scenario and the pessimistic future scenario, respectively.

The impact of deep learning image reconstruction of spectral CTU virtual non contrast images for patients with renal stones

PurposeTo compare image quality and detection accuracy of renal stones between deep learning image reconstruction (DLIR) and Adaptive Statistical Iterative Reconstruction-Veo (ASIR-V) reconstructed virtual non-contrast (VNC) images and true non-contrast (TNC) images in spectral CT Urography (CTU). MethodsA retrospective analysis was conducted on images of 70 patients who underwent abdominal-pelvic CTU in TNC phase using non-contrast scan and contrast-enhanced corticomedullary phase (CP) and excretory phase (EP) using spectral scan. The TNC scan was reconstructed using ASIR-V70 % (TNC-AR70), contrast-enhanced scans were reconstructed using AR70, DLIR medium-level (DM), and high-level (DH) to obtain CP-VNC-AR70/DM/DH and EP-VNC-AR70/DM/DH image groups, respectively. CT value, image quality and kidney stones quantification accuracy were measured and compared among groups. The subjective evaluation was independently assessed by two senior radiologists using the 5-point Likert scale for image quality and lesion visibility. ResultsDH images were superior to AR70 and DM images in objective image quality evaluation. There was no statistical difference in the liver and spleen (both P > 0.05), or within 6HU in renal and fat in CT value between VNC and TNC images. EP-VNC-DH had the lowest image noise, highest SNR, and CNR, and VNC-AR70 images had better noise and SNR performance than TNC-AR70 images (all p < 0.05). EP-VNC-DH had the highest subjective image quality, and CP-VNC-DH performed the best in lesion visibility. In stone CT value and volume measurements, there was no statistical difference between VNC and TNC (P > 0.05). ConclusionThe DLIR-reconstructed VNC images in CTU provide better image quality than the ASIR-V reconstructed TNC images and similar quantification accuracy for kidney stones for potential dose savings.The study highlights that deep learning image reconstruction (DLIR)-reconstructed virtual non-contrast (VNC) images in spectral CT Urography (CTU) offer improved image quality compared to traditional true non-contrast (TNC) images, while maintaining similar accuracy in kidney stone detection, suggesting potential dose savings in clinical practice.