bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical Analysis of Solidification in Molten Salt-Air Shell-and-Tube Heat Exchangers
Authors: K. Raj Arun , B. Desai Nishith , Haglind Fredrik
Published: September 2024

The cyclic operation of molten salt heat exchangers raises concern regarding the potential freezing of salts due to their high freezing point. Therefore, pinpointing the initiation of salt solidification and forecasting the phase change behavior in high-temperature heat exchange processes is necessary, as these factors influence the design and operation of the heat exchangers. This paper presents a three-dimensional, transient computational fluid dynamics analysis of a pilot-scale molten salt-air-cooled exchanger with air on the shell-side and molten salt on the tube-side. We aim to replicate the conditions the molten salt experiences during operation in a concentrating solar power plant or pumped thermal energy systems. Consequently, the study explores the influence of the initial molten salt temperature and the baffle configuration on the air outlet temperature, pressure drop and onset of salt solidification. A realizable k-ε turbulence model was adopted to capture the turbulent viscosity and dissipation rate, and a segregated solver algorithm was used to iteratively solve the coupling between the pressure and velocity fields. The numerical model was validated using previous results of a shell-and-tube heat exchanger employing pure water as the shell-side fluid. The main novel contribution of this work is to estimate the time it takes until the molten salt begins to solidify within the tube bundle when air acts as the working fluid on the shell-side of a single segmented baffled shell-and-tube-type heat exchanger. Additionally, it aims to ascertain the impact of inclusion of a flow diverter on delaying the salt solidification. The findings indicate that varying the baffle configurations has little to no effect on the air outlet temperature nor on the onset of molten salt solidification for all tested configurations without a flow diverter. Concurrently, inclusion of flow diverter helps redistribute the flow near the shell inlet nozzle, thereby delaying the onset of solidification. Furthermore, the results suggest that about one-third of the total heat exchanger length proves to be ineffective in contributing to the heat transfer, due to the creation of recirculation zones. These results serve as a benchmark for future heat transfer analyses of the dynamic operation of the molten salt-air-cooled heat exchangers.
Assessment of Fluidized Bed Heat Exchanger Techno Economics Considering Parasitic Pumping Power
Authors: Lerch Dylan J. , Schroeder Nathan R.
Published: September 2024

The Department of Energy’s Solar Energy Technologies Office has down selected a particle-based heat transfer and storage medium as the technology most likely to decrease the levelized cost of energy of concentrating solar power to below their 0.05 $/kWh target by 2030. A particularly challenging component within a particle-based system is the particle to supercritical CO2 heat exchanger due to the relatively low thermal conductivity and poor heat transfer characteristics of the particle media. Fluidized bed heat exchangers have widely been used in industry for alternative applications and feature high particle side heat transfer coefficients that can help reduce the cost of the heat exchanger. This increase in heat transfer coefficient is achieved by bubbling air through the particles which increases their movement relative to the tube bundle heat transfer surface. The parasitic power associated with the delivery of air into the heat exchanger introduces a concern that the levelized cost of energy would be negatively impacted when compared to the state of the art parallel plate heat exchanger which relies on gravity for particle flow. The presented study reveals that the levelized cost of electricity of the fluidized bed heat exchanger design was up to 0.007 $/kWh lower than the state of the art parallel plate heat exchanger despite the increased parasitic power consumption. It is also presented that the increase in heat transfer coefficient, and thus decreased heat exchanger material, gained from increased airflow in the bed does not result in lower levelized cost of energy. The minimum air flow required for fluidization provides in the lowest levelized cost of energy due to the minimal parasitic power consumption.
A Low Cost 20 MW Commercial Ocean Thermal Energy Plant for Tropical Regions
Authors: Anderson James H.
Published: September 2024

Ocean Thermal Energy Conversion (OTEC) has been seriously proposed as a natural and clean source of electric power starting in the late 1880’s. Through the 20th and now in the 21st century there have been numerous experiments, cycle developments, testing of components, environmental studies, and even small plants that prove OTEC is possible. Constantly, however, the cumulative call argues for the actual construction and installation of a prototype OTEC plant of commercial size, connected to a national municipal electric grid. Most less developed and smaller developed island and coastal tropical nations generate the bulk of their power with diesel fuel. This paper will describe how a 20 MW net prototype commercial OTEC plant can be built and installed in hundreds of tropical locations around the world today and produce reliable, continuous, baseload electricity at a lower cost than that generated from diesel fuel. In addition, a prototype plant of the design presented here can be profitable for any investor even without subsidies.
Quantifying Thermal Discomfort in Built Environment for Major Cities in Saudi Arabia
Authors: Ullah Safi , Tahir Furqan , Al-Ghamdi Sami G.
Published: September 2024

Human-induced climate change has intensified the thermal discomfort people experience in urban living. Despite the substantial risks this poses to public health, there is a notable gap in comprehensive research assessing the spatial and temporal shifts in human thermal discomfort and its specific characteristics in hot-hyper arid regions, one such example is Saudi Arabia. During heat waves, daily temperatures may surpass 50°C in the country, presenting a substantial risk to the health and well-being of residents. It is estimated that the building energy requirement is more than 50% of the total power consumption. Hence, it is critical to quantify thermal discomfort in terms of both thermal stress and intensity. Therefore, this work focused on analyzing thermal discomfort using the universal thermal climate index (UTCI) for efficient building design. Five major cities including Dammam, Jeddah, Madinah, Makkah, and Riyadh, were selected and examined from 1980–2022. The prominent urban hubs have encountered notable rises in UTCI, registering an increase ranging from 0.30 to 0.54 °C, marked by heightened frequency and intensity during the study period. The study’s findings can inform building design, enhance human comfort conditions, and shape future building codes and policies.
Evaluation and CFD Based Improvements of Reactive Reversible Blade Turbine
Authors: Patil Abhay , Katcher Kelsi , Allison Tim , Cummings Scot
Published: September 2024

A Reactive Reversible Blade Turbine (RRBT) is a cross-flow type turbine design with multiple movable blades that pivot around their local axes to hydraulically balance the blade forces while passing through the negative drag portion of the flow regime. The RRBT allows the blades to react to the negative drag and freely rotate in a way that hydraulically balances the pressure loading. The blades “slice” through the water in a reverse motion, returning to a neutral position and resting against a stop, resulting in reduced resistance on the opposite side of the turbine shaft during rotation. This allows for a significant reduction of the negative drag during the single rotation of the turbine, which improves the power coefficients compared to the current state of the art and allows the turbine to operate at a slow-moving current. Although the design is simple, there is a broad design optimization space that can impact the performance and development of this turbine for various applications. This paper focuses on developing a transient numerical model using a moving mesh approach of a single blade to characterize the flow dynamics and performance estimation. The predicted power coefficient (Cp) of 0.219, using computational fluid dynamics (CFD), aligns well with the experimentally measured value of 0.2 at a 0.32 Tip Speed Ratio (TSR). Further investigation focuses on gaining a deeper understanding of turbine performance concerning changes in blade profile, blade angles, blade widths, and scaling effects. The design space exploration study reveals that the blade angle has a substantial impact on turbine performance, particularly in shifting the peak power coefficient with the TSR. As the blade angle increases, the power coefficient rises, peaking at around 72°, followed by a decrease as the blade angle further increases. The Reynolds number scaling also indicates an approximately 20% increase in peak Cp due to the increased hydrodynamic size for the scaling from 1X to 5X. It is essential to note that these findings are based on the analysis of a single blade, and additional investigation and experimental validation are necessary to comprehensively assess the performance of the proposed design modifications.
Water Transport in Membrane of PEM Fuel Cell Under Transient Operation
Authors: Nguyen Ngoc Dat , Trinh Ngoc Van , Kim Younghyeon , Yu Sangseok
Published: September 2024

In this study, the primary focus is investigating the transient behaviors of water transport in the membrane when the cell voltage reaches its lowest values during acceleration. To cope with the objective, this study involved the installation of multiple micro relative humidity and temperature sensors in the bipolar plate channels to measure the temperature and water distribution in the flow fields both on the cathode and anode of a single cell PEMFC. Experiments have been conducted to acquire temperature and water distribution change data under varying load conditions with different time intervals. The current density was systematically adjusted from 0.1A/cm2 to 0.4A/cm2. Time intervals of 0 seconds and 5 seconds have been introduced to control the rapidity of acceleration process. This approach allowed for examining water transport characteristics in the membrane during transient operation. Specifically, an ANN (Artificial Neural Network)-based model has been developed to predict membrane water content. The net water mole flux transported in the membrane as the sum of electro-osmotic force and back-diffusion force is calculated based on the measured temperature and relative humidity by combining the ANN-based model with other empirical correlations. The research provides visual information about the water transport in the membrane during the transient state. The data corresponding to different acceleration time intervals are compared to assess the time-dependent effects of load changes. It is evident that the time intervals of acceleration significantly influence the water characteristics in the membrane and output voltage of operating PEMFC. This study contributes significantly to enhancing the knowledge of water transport transient behaviors in the membrane of PEMFC, providing the foundation for further research to improve the performance and durability of PEMFC for transportation applications.
Investigation on the Catalytic Ability of Alkaline Earth Metal Cations and Nitrite Anions on Low Temperature Molten Salt Torrefaction
Authors: Kohlin Lee , Pritchard Hayden , Heidari DehKordi Behrooz , Gladen Adam C. , Bajwa Dilpreet
Published: September 2024

The present study investigates the catalytic ability of alkaline earth metal nitrates (calcium and magnesium nitrate), of nitrite (NO2) anions, and of low lithium nitrate-containing salt blends on low temperature molten salt torrefaction of ponderosa pine and cave-in-rock switchgrass. Severity of torrefaction is characterized by analyzing mass yields, higher heating values (HHV), chemical composition, and pH of the torrefied biomass. Results show that torrefaction with magnesium nitrate produces a solid, non-water-soluble byproduct and results in low torrefied biomass mass yields. However, Mg appears to be more catalytic than Ca, wherein Mg decomposes cellulose and hemicellulose to a greater degree than Ca from torrefaction at the same temperature. Based on mass yields and chemical composition at 240°C, Ca is slightly more catalytic than K. Additionally, at 240°C, blends containing Ca are shown to have simultaneously higher mass yields and HHV compared to inert gas torrefaction, effectively increasing energy yields. The reactivity of nitrite anions increases sensitivity to temperature and provides severe decomposition of pine. For example, the HHV of pine torrefied in nitrites at 190°C is 0.31MJ/kg higher than pine torrefied in inert gas at 240°C. For salts containing a small amount of lithium nitrate, changes in the lithium content impacts the torrefaction severity. Increasing lithium content from 3wt% to 5wt%, results in more than a 4% increase in HHV for both feedstocks and a large decrease in mass yield of pine (12%) and switchgrass (23%).
Machine Learning Based Assessment of the Air Quality Impacts From Natural Gas Production Facilities in Denton County, Texas
Authors: Kanayankottupoyil Jithin , John Kuruvilla
Published: September 2024

This study presents a comprehensive approach to predicting total non-methane organic compounds (TNMOC) concentrations in the Dallas-Fort Worth (DFW) area, a region marked by significant oil and gas production. Leveraging 23 years of data, including production volumes from the Denton Airport South, along with pollution and meteorological parameters. The Machine Learning (ML) models were trained using the comprehensive dataset of TNMOCs, NO2 and ozone concentration data, along with natural gas production volumes and meteorological data from Denton Airport South site. By incorporating features such as production volume, meteorological data, and pollution concentration, the models provided robust forecasts of the concentration of TNMOCs. Special emphasis was placed on the years 2014 and 2018, which marked a peak and subsequent decline in both TNMOC concentrations and production volumes, respectively. The study employed Random Forest (RF) and eXtreme Gradient Boosting (XGBoost) for a comparative analysis. The findings indicated that RF slightly surpassed XGBoost in the overall dataset, as reflected by an R2 of 0.77 and favorable error metrics. The predictive models, particularly for 2014 and 2018, were proficiently constructed, with RF demonstrating enhanced predictive accuracy (predictive R2 of 0.89) over its training R2 of 0.88. Conversely, XGBoost, despite its robust training performance (R2 of 0.95), exhibited a reduction in predictive effectiveness (predictive R2 of 0.83), suggesting challenges in accommodating specific years marked by notable TNMOC concentration fluctuations. Our findings provide insights into strategies for reducing TNMOC concentrations and it underscores the potential utilization of advanced machine learning techniques in air pollution prediction models. The methodology and results of this study can be adapted for similar environmental analyses elsewhere, particularly in regions were oil and gas activities impact air quality.
Design and Operation Optimization of an Integrated Solar-Powered Organic Rankine Cycle System With Energy Storage
Authors: Maharjan Krisha , Cho Heejin , Mago Pedro , Yaïci Wahiba , Cui Qinrong , Zhang Jian
Published: September 2024

Addressing the environmental and economic concerns related to energy use in buildings has prompted a global emphasis on energy sustainability by reducing dependence on fossil fuels and promoting cleaner alternatives. One such alternative for utilizing renewable sources is the organic Rankine cycle (ORC) system. In this paper, an integrated solar-powered organic Rankine cycle with battery energy storage (ORC-BES) system is proposed, and its performance is optimized with the objectives of reducing operational cost, capital cost, and carbon dioxide emission (CDE) for different building types and locations. The proposed system, which includes organic Rankine cycle, flat plate solar thermal collector (FPC), and battery energy storage, is configured in such a manner that the solar-powered ORC generates electricity for the building during daytime while the BES stores excess electricity for later use. A multi-objective particle swarm optimization (MOPSO) is adopted to determine the optimal battery size and solar thermal collector size for the proposed ORC-BES system. Several different dry organic fluids are selected to evaluate the performance of the system. The building types under investigation in this paper include hospitals and large offices, which are the commercial reference building models developed by the Department of Energy (DOE). Several locations separated in different climate zones in the United States, including California, New Mexico, Texas, Florida, and Georgia are chosen as case studies to present the optimization results. Results show that the proposed optimization method can be effectively applied to the ORC-BES system to obtain an optimal design and operation, which reaches a trade-off between the economic, energy, and environmental performance of different buildings and locations.
Balancing Concentrating Solar Power and Thermal Storage With Photovoltaics and Battery Storage to Meet Carbon-Free Electricity and Resilience Goals
Authors: Braid Jennifer L. , McLaughlin Luke , Schroeder Nathan , Laubscher Henk , Sment Jeremy , Stein Joshua S.
Published: September 2024

Concentrating solar power (CSP) plants with integrated thermal energy storage (TES) have successfully been coupled with photovoltaics (PV) + chemical battery energy storage (BES) in recent commercial-scale projects to balance system cost and diurnal power availability. Sandia National Laboratories has been tasked with designing an advanced solar energy system to power Kirtland Air Force Base (KAFB) where Sandia is co-located in Albuquerque, NM, USA. This design process requires optimization of individual components and capacities of the hybrid system. Preliminary modeling efforts have shown that a hybrid CSP+TES/PV+BES in Albuquerque, NM is sufficient for net-zero power generation for Sandia/KAFB for the next decade. However, the ability to meet the load in real-time (and minimize energy export) requires balance of generation and storage assets. Our results also show that excess PV used to charge TES improves resilience and overall renewables-to-load for the system. Here we will present the results of a parametric study varying the land use proportions of CSP and PV, and TES and BES capacities. We evaluate the effects of these variables on energy generation, real-time load satisfaction, site resilience to grid outages, and LCOE, to determine viable hybrid solar energy designs and their cost implications.
An Energy-Sustainable Approach of Ginger Rhizomes Hydrosol Extraction Using a Solar Thermal Hydrodistillation System
Authors: Katekar Vikrant P. , Rao Anand B. , Sardeshpande Vishal R.
Published: September 2024

Ginger hydrosol spray may be used for various purposes, including renewing skin, relieving coughs and congestion, calming skin rashes, reducing stress, and providing pain relief. India is the world’s leading producer of ginger. However, smaller-sized ginger rhizomes are difficult to sell on the market. In this circumstance, creating a hydrosol and selling it to the market is a viable business opportunity for farmers. However, typical steam distillation systems are out of reach for most farmers; hence, the present work shows how to extract ginger hydrosol using a solar thermal hydrodistillation approach. On a typical day, the average basin water temperature was 55°C, while the absorber plate temperature was 58°C. In the evening, the vapour temperature was much higher (42.8%) than the glass cover temperature. As a result, condensation stayed far after the sun had set. The average ginger hydrosol production rate was 3.7 kg/day. According to estimations, energy efficiency averages 26.3%. The chemical analysis indicates that it has antibacterial activity and is safe to drink. With 270 working days per year and a selling price of ₹100 per kg ($ 1.2 per kg), the payback period was 41 sunny days, and the total carbon credits earned was ₹3956.13 ($47.4).
Gut microbiota dysbiosis and neurological function recovery after intracerebral hemorrhage: an analysis of clinical samples
Authors: Wang Yan , Bing Hailong , Jiang Conghui , Wang Jie , Wang Xuan , Xia Zhengyuan , Chu Qinjun
Published: September 2024

We aimed to investigate the microbial community composition in patients with intracerebral hemorrhage (ICH) and its effect on prognosis. We designed two clinical cohort studies to explore the gut dysbiosis after ICH and their relationship with neurological function prognosis. First, fecal samples from patients with ICH at three time points: T1 (within 24 h of admission), T2 (3 days after surgery), and T3 (7 days after surgery), and healthy volunteers were subjected to 16S rRNA sequencing using Illumina high-throughput sequencing technology. When differential gut microbiota was identified, the correlation between clinical indicators and microbiotas was analyzed. Subsequently, the patients with ICH were categorized into GOOD and POOR groups based on their Glasgow Outcome Scale Extended (GOS-E) score, and the disparities in gut microbiota between the two groups were assessed. Univariate and multivariate logistic regression analyses were performed to identify independent risk factors. The composition and diversity of the gut microbiota in patients with ICH were different from those in the control group and changed dynamically with the extension of the course of cerebral hemorrhage. The abundances of
Enterococcaceae
,
Clostridiales incertae sedis XI
, and
Peptoniphilaceae
were significantly increased in patients with ICH, whereas
Bacteroidaceae
,
Ruminococcaceae
,
Lachnospiraceae
, and
Veillonellaceae
were significantly reduced. The relative abundance of
Enterococcus
gradually increased with the extension of the duration of ICH after surgery, and the abundance of
Bacteroides
gradually decreased. The abundance of
Enterococcus
before surgery was found to be negatively associated with patient neurological function prognosis. The original ICH score and
Lachnospiraceae
status were independent risk factors for predicting the prognosis of neurological function in patients with ICH (
P
< 0.05). Changes in the gut microbiota diversity in patients with ICH were related to prognosis.
Lachnospiraceae
may have a protective effect on prognosis.

IMPORTANCE

Acute central nervous system injuries like hemorrhagic stroke are major global health issues. While surgical hematoma removal can alleviate brain damage, severe cases still have a high 1-month mortality rate of up to 40%. Gut microbiota significantly impacts health, and treatments like fecal microbiota transplantation (FMT) and probiotics can improve brain damage by correcting gut microbiota imbalances caused by ischemic stroke. However, few clinical studies have explored this relationship in hemorrhagic stroke. This study investigated the impact of cerebral hemorrhage on the composition of gut microbiota, and we found that
Lachnospiraceae
were the independent risk factors for poor prognosis in intracerebral hemorrhage (ICH). The findings offer potential insights for the application of FMT in patients with ICH, and it may improve the prognosis of patients.
Micronutrient availability alters
Candida albicans
growth and farnesol accumulation: implications for studies using RPMI-1640
Authors: Boone Cory H. T. , Gutzmann Daniel J. , Kramer Jaxon J. , Urbin Shyanne D. , Navarathna Dhammika H. , Atkin Audrey L. , Nickerson Kenneth W.
Published: September 2024

Science is challenging because we do not know what we do not know. Commercial chemicals are often marketed with >99% purity, but 0.5–1% impurity can impact results and cloud data interpretation. We recently developed an assay for farnesol and aromatic fusel alcohols from
Candida albicans
. During proof-of-concept experiments using RPMI-1640 growth media, the buffering compound was switched from MOPS obtained from Acros Organics to MOPS obtained from Sigma-Aldrich, both labeled 99% + purity. We observed a twofold decrease in growth, along with a three- to fivefold increase in farnesol production per cell upon the switch. ICP-MS showed that trace Mn(II) was present in Acros MOPS but absent in Sigma MOPS. Optimal growth was achieved by the addition of Mn(II), Zn(II), and Fe(II). We established upper and lower limits for Fe(II), Zn(II), Cu(II), and Mn(II) that allowed similar growth and then assessed 16 different mineral combinations in RPMI-1640 base media. The results show an increased production of farnesol and the aromatic fusel alcohols when Zn(II) is abundant, and a further increase in the aromatic fusel alcohols when both Fe(II) and Zn(II) are abundant. Finally, antifungal susceptibility testing displayed no significant difference between RPMI/MOPS with and without mineral supplementation. Supplemental Mn(II) was most needed for cell growth, while supplemental Zn(II) was most needed for the production of farnesol and the aromatic fusel alcohols. To avoid these artifacts due to metal contamination, we now use a modified RPMI supplemented with 1 mg/ L of Cu(II), Zn(II), Mn(II), and Fe(II).

IMPORTANCE

The dimorphic fungus
Candida albicans
is a major opportunistic pathogen of humans. RPMI-1640 is a chemically defined growth medium commonly used with
C. albicans
. We identified over 32,000 publications with keywords RPMI and
C. albicans
. Additionally, Antifungal Susceptibility Testing (AFST) protocols in the United States (CLSI) and Europe (EUCAST) utilize RPMI as a base media to assess drug efficacy against clinical fungal isolates. RPMI contains many nutrients but no added trace metals. We found that the growth characteristics with RPMI were dependent on which MOPS buffer was chosen and the contamination of that buffer by trace levels of Mn(II) and Zn(II). Added Mn(II) was most needed for cell growth while added Zn(II) was most needed for secretion of farnesol and other signaling molecules.
Postoperative laryngeal granuloma in mediastinal goitre with gastro-oesophageal reflux disease
Authors: Taniguchi Takaya , Suzuki Masami
Published: September 2024

Reported postoperative complications of mediastinal goitre include recurrent laryngeal nerve palsy, hypoparathyroidism and tracheomalacia. Voice and swallowing symptoms after thyroid surgery have been associated with laryngopharyngeal reflux, but it is unclear whether the retrograde flow of gastric contents into the oesophagus, larynx and pharynx worsens after thyroid surgery. We present the case of a man in his 40s with gastro-oesophageal reflux disease (GERD) who developed heartburn and laryngeal granuloma after total thyroidectomy for mediastinal goitre. Vonoprazan therapy effectively controlled these symptoms. Although the exact cause remains unclear, we suggest that changes in pressure dynamics after thyroidectomy may worsen the retrograde flow of gastric contents into the oesophagus, larynx and pharynx, contributing to GERD symptoms and laryngeal granuloma. This case highlights the need to consider the management of retrograde flow of gastric contents into the oesophagus, larynx and pharynx in the postoperative care of mediastinal goitre resections.
Outcomes of gonioscopy-assisted transluminal trabeculotomy in advanced pigmentary glaucoma
Authors: Panigrahi Arnav , Kumar Anurag , Gupta Shikha , Grover Davinder S , Gupta Viney
Published: September 2024

Purpose

To compare outcomes of gonioscopy-assisted transluminal trabeculotomy (GATT) over a 12-month period with trabeculectomy in patients with advanced pigmentary glaucoma (PG).

Methods

This was a pilot randomised controlled trial of patients with advanced PG (mean deviation worse than −12 dB), undergoing either GATT or a fornix-based trabeculectomy. Absolute success (criterion A) was defined as a postoperative intraocular pressure (IOP) between 6 and 18 mm Hg, with a drop of at least 30% from the treated preoperative value without need of any IOP-lowering medication. Success (criterion B) was also defined as per the target IOP, with an upper limit of 15 mm Hg for eyes with mean deviation (MD) between −12 and −24 dB, and 12 mm Hg or lower for MD values worse than −24 dB. Qualified success was a similar IOP standard on the same or fewer antiglaucoma medications.

Results

For GATT (n=10), mean preoperative IOP and number of glaucoma medications were 28.2±11.2 mm Hg and 4±0.8 that reduced to 11.8±2.5 mm Hg and 0.7 at 12 months postoperatively, while in the trabeculectomy (n=12) group, they were 27.3±5.5 mm Hg and 3.6±0.7 that reduced to 11.5±2.2 mm Hg and 0.5±0.9, respectively. All eyes (100%) achieved qualified success. Absolute success was 60% and 67.7% by criterion A and 50% and 58.3% by criterion B for GATT and trabeculectomy, respectively. Two eyes in the trabeculectomy group developed hypotony while none of the GATT group had any sight-threatening complications (p=0.4).

Conclusions

GATT alone demonstrated a significant reduction in IOP and number of glaucoma medications in patients with advanced PG.
Understanding the preferences of young women in self-sampling interventions for sexually transmitted infection diagnosis: a discrete choice experimental protocol
Authors: Jaya Ziningi Nobuhle , Mapanga Witness , Mashamba-Thompson Tivani Phosa
Published: September 2024

Introduction

Sexually transmitted infections (STIs) are a significant public health concern globally, particularly affecting young women. Early diagnosis and treatment are essential to reducing or stopping the continuous spread of infections and the development of associated complications. Syndromic management, which is commonly used for STIs, presents several barriers, particularly for young women. This protocol is for a study that aims to understand young women’s preferences for a self-sampling intervention for STI diagnosis by using a discrete choice experiment (DCE). The DCE will be conducted among young women residing in underserved urban communities in eThekwini Metropolitan Municipality in KwaZulu-Natal, South Africa.

Methods and analysis

The following attributes of a self-sampling intervention were identified through a Nominal Group Technique: accessibility, education, confidentiality, self-sampling method, youth-friendliness and cost. A pilot study involving 20 participants was conducted to refine the DCE questionnaire. A total of 196 young women from underserved communities will be recruited. The participants will be sampled from communities, stratified by settlement type and socioeconomic status. Data will be analysed using the multinomial logit model and mixed logit model to assess preferences and heterogeneity.

Ethics and dissemination

The study was approved by the Faculty of Health Sciences Research Ethics Committee of the University of Pretoria. The study findings have the potential to inform policies for STI treatment and management to align healthcare services with user preferences. This can improve STI healthcare access for young women in underserved communities. Ethical approval was obtained, and results will be disseminated through peer-reviewed journals and health conferences.
Cost comparison analysis of continuous versus intermittent antimicrobial therapy infusions in inpatient and outpatient care: real-world data from Finland
Authors: Hakkarainen Tuukka , Lahelma Mari , Rahkonen Terhi , Lehtinen Ville , Shepelev Julian , Gram Trine , Heikkila Eija
Published: September 2024

Objective

This study compared the costs and nursing time associated with the delivery of continuous infusion of antibiotics via elastomeric infusion pumps (EIP) versus conventional intermittent infusion (CII) across different care pathways.

Design

Retrospective real-world data informed a cost comparison analysis that compared costs and nursing hours between infusion of antibiotics via EIP versus CII across eight care pathways in inpatient or outpatient care during infection episodes. Real-world data were obtained from patients treated within a year with parenteral antimicrobial therapy in Päijät-Häme Region, Finland.

Setting

Inpatient care with hospital admission and outpatient care at hospital at home in Päijät-Häme Region in Finland.

Participants

3778 patients with a total of 4214 infection episodes treated with intravenous antimicrobial therapy.

Interventions

Eight treatment strategies with various combinations of EIP and CII administered in inpatient or outpatient care.

Primary and secondary outcome measures

Direct costs and nursing time.

Results

Skin and soft tissue infections accounted for the highest number of episodes treated with EIP overall (30.8%; 74 out of 240 episodes) and in outpatient care specifically (53.3%; 128 out of 240 episodes). Compared with inpatient care costs with CII (€4590 per episode), treating skin and soft tissue infections in outpatient care with EIP or CII incurred only 24% (€1104) and 35% (€1620) of the costs, respectively. Across all treatment strategies and infections studied, the use of EIP consistently required less nursing time. The highest nursing time in the outpatient care was observed in sepsis episodes treated with CII (37 hours with CII vs 7 hours with EIP per episode).

Conclusion

Delivery of antimicrobial therapy using continuous infusions with EIP instead of CII can significantly decrease the nursing time and cost in both inpatient and outpatient care. For skin and soft tissue infections and sepsis, the utilisation of EIP is a cost-saving option in outpatient care compared with the use of CII.
Feasibility, safety and preliminary efficacy of preoperative stereotactic radiotherapy on the future pancreatic neck transection margin to reduce the risk of pancreatic fistula after high-risk pancreatoduodenectomy (FIBROPANC): protocol for a multicentre, single-arm trial
Authors: Suurmeijer J. Annelie , Wismans Leonoor V. , Hendriks Tessa E. , Bruynzeel Anna M. , Nuyttens Joost J. , Intven Martijn P.W. , van Driel Lydi M.J.W. , Groot Koerkamp Bas , Busch Olivier R. , Stoker Jaap J. , Verheij Joanne , Farina Arantza , Doukas Michail , de Hingh Ignace H.J. , Lips Daan J. , van der Harst Erwin , van Tienhoven Geertjan , Besselink Marc G. , van Eijck Casper H.J.
Published: September 2024

Introduction

Postoperative pancreatic fistula (POPF) occurs in 25% of patients undergoing a high-risk pancreatoduodenectomy (PD) and is a driving cause of major morbidity, mortality, prolonged hospital stay and increased costs after PD. There is a need for perioperative methods to decrease these risks. In recent studies, preoperative chemoradiotherapy in patients with pancreatic ductal adenocarcinoma (PDAC) reduced the rate of POPF seemingly due to radiation-induced pancreatic fibrosis. However, patients with a high risk of POPF mostly have a non-pancreatic periampullary tumour and do not receive radiotherapy. Prospective studies using radiotherapy specifically to reduce the risk of POPF have not been performed. We aim to assess the safety, feasibility and preliminary efficacy of preoperative stereotactic radiotherapy on the future pancreatic neck transection margin to reduce the rate of POPF.

Methods and analysis

In this multicentre, single-arm, phase II trial, we aim to assess the feasibility and safety of a single fraction of preoperative stereotactic radiotherapy (12 Gy) to a 4 cm area around the future pancreatic neck transection margin in patients at high risk of developing POPF after PD aimed to reduce the risk of grade B/C POPF. Adult patients scheduled for PD for malignant and premalignant periampullary tumours, excluding PDAC, with a pancreatic duct diameter ≤3 mm will be included in centres participating in the Dutch Pancreatic Cancer Group. The primary outcome is the safety and feasibility of single-dose preoperative stereotactic radiotherapy before PD. The most relevant secondary outcomes are grade B/C POPF and the difference in the extent of fibrosis between the radiated and non-radiated (uncinate margin) pancreas. Evaluation of endpoints will be performed after inclusion of 33 eligible patients.

Ethics and dissemination

Ethical approval was obtained by the Amsterdam UMC’s accredited Medical Research Ethics Committee (METC). All included patients are required to have provided written informed consent. The results of this trial will be used to determine the need for a randomised controlled phase III trial and submitted to a high-impact peer-reviewed medical journal regardless of the study outcome.

Trial registration number

NL72913 (Central Committee on Research involving Human Subjects Registry) andNCT05641233(ClinicalTrials).
Investigation of the knowledge, attitude and practice regarding nutrition in older adults with tuberculosis and diabetes: a cross-sectional study in Eastern China
Authors: Huang Juanli , Gao Xuenong , Meng Xuyun , Yang Juan , Wang Lijun
Published: September 2024

Objectives

Older adults with tuberculosis and diabetes have special needs regarding dietary nutrition. This study aimed to investigate the knowledge, attitude and practice (KAP) regarding dietary nutrition among older adults with those two conditions.

Design

Cross-sectional study.

Setting

Three tertiary medical centres in China.

Participants

Adults over 60 year old diagnosed with tuberculosis and diabetes.

Interventions

Between July 2023 and October 2023.

Primary and secondary outcome measures

Demographic characteristics and KAP scores collected by self-designed questionnaire.

Results

A total of 456 valid questionnaires were analysed, with 261 (57.24%) participants being over 70 years old. The mean scores were 6.84±3.16 (possible range: 0–24) for knowledge, 23.23±2.23 (possible range: 8–40) for attitude and 22.73±3.14 (possible range: 8–40) for practice, respectively. Correlation analysis revealed significant positive correlations between knowledge and attitude (r=0.287, p<0.001), knowledge and practice (r=0.189, p<0.001) and attitude and practice (r=0.176, p<0.001). Structural equation modelling demonstrated that knowledge significantly influenced attitude (β=0.343, 95% CI (0.257 to 0.422), p<0.001) and practice (β=0.245, 95% CI (0.101 to 0.405), p<0.001) and attitude significantly influenced practice (β=0.274, 95% CI (0.146 to 0.405), p<0.001).

Conclusions

The study highlights a need for improvements in dietary nutrition practices for older adults with tuberculosis and diabetes. Findings emphasise the urgency of enhancing dietary education among this population in China. Implementation of targeted educational programmes is warranted to improve knowledge, foster positive attitudes and encourage healthier dietary practices, ultimately leading to improved patient outcomes and well-being.
Endovascular thrombectomy versus medical management for patients with large vessel stroke and infective endocarditis
Authors: Chen Huanwen , Colasurdo Marco , Khunte Mihir , Malhotra Ajay , Gandhi Dheeraj
Published: September 2024

Background

The safety and efficacy of endovascular thrombectomy (EVT) for large vessel occlusion (LVO) strokes associated with infective endocarditis (IE) compared with medical management (MM) is unclear.

Methods

In this nationwide analysis of hospitalizations in the United States, we assessed the outcomes of EVT versus medical management (MM) for patients with LVO and IE. Primary outcome was routine home discharge with self-care. Secondary outcomes include home discharge, in-hospital mortality, intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH). Propensity score matching (PSM) was performed to adjust for confounders. Additional multivariable adjustments were performed for doubly robust analyses.

Results

2574 patients were identified; 656 (25.5%) received EVT. After PSM, the rate of routine discharge was significantly higher for patients with EVT compared with MM (14.6% vs 8.5%, p=0.021), and patients with EVT had significantly higher rate of home discharge (34.5% vs 26.5%, p=0.041), lower rate of in-hospital death (14.8% vs 25.2%, p=0.002), and lower rate of ICH (15.8% vs 23.1%, p=0.039). EVT was not associated with a different rate of SAH compared with MM (11.2% vs 7.9%, p=0.17). These associations remained unchanged with additional multivariable adjustments.

Conclusion

For patients with LVO stroke and IE, EVT was associated with significantly higher odds of favorable hospitalization outcomes and lower odds of ICH compared with MM.
A One Health perspective on recreational fisheries
Authors: Cooke Steven J. , Danylchuk Andy J. , Zhang Joel , Nguyen Vivian M. , Hunt Len M. , Arlinghaus Robert , Fiorella Kathryn J. , Chan Hing Man , Goldberg Tony L.
Published: September 2024

Recreational fisheries involve an intimate connection between people, individual fish, and the environment. Recreational fishers and their health crucially depend on healthy fish and ecosystems. Similarly, fish and ecosystems can be impacted by the activities of people including recreational fishers. Thus, amplified by the global interest in recreational fishing, we posit that recreational fishing is particularly suited as an empirical system to explore a One Health perspective, with a goal of creating pathways to better manage such socio-ecological systems for the benefit of people, fish, and the environment. Although zoonoses are uncommon in fishes, fish can carry pathogens, biotoxins, or contaminants that are harmful to people. When captured and released, fish can experience stress and injuries that may promote pathogen development. Similarly, when humans contribute to environmental degradation, not only are fish impacted but so are the humans that depend on them for nutrition, livelihoods, culture, and well-being. Failure to embrace the One Health perspective for recreational fisheries has the potential to negatively impact the health of fish, fisheries, people, society, and the aquatic environment—especially important since these complex social–ecological systems are undergoing rapid change.
Synthesis and characterizations of a novel hydrogel for adsorptive removal of crystal violet dye from wastewater
Authors: Gautam Samiksha , Kumar Vijay
Published: September 2024

Herein, a novel hydrogel (HG-cl-poly(AA)) was synthesized by grafting acrylic acid (AA) onto Hing gum (HG) using methylene-bis-acrylamide (MBA) as a cross-linker and ammonium persulfate (APS) as an initiator in a hot air oven. The percentage swelling of the hydrogel was examined by optimizing various reaction parameters to ensure its maximum swelling percentage. The formation of crosslinked networks was confirmed using Fourier-Transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and thermogravimetric analysis (TGA) techniques. The surface area and hydrophilicity of the prepared hydrogel were determined using Brunauer–Emmett–Teller analyzer and wettability studies, demonstrating a clear correlation with adsorption. The adsorption of crystal violet (CV) dye on the prepared hydrogel was studied via a batch adsorption system based on the amount of adsorbent, immersion time, pH level, and initial dye concentration. The prepared hydrogel showed a 99% removal rate and an excellent adsorption capacity of 492.61[Formula: see text]mg/g due to the electrostatic, H-bonding, and dipole–dipole interactions between the adsorbent surface and dye molecules. The results were further analyzed using the Langmuir, Freundlich, and Tempkin isotherm models. The study suggests consistency with the pseudo-second-order kinetic model ([Formula: see text]), further supported by the best data fit with the Langmuir isotherm model ([Formula: see text]). The thermodynamic study results indicated that the adsorption process is endothermic and spontaneous. Regeneration (desorption) studies showed that the prepared hydrogel could remove CV dye from an aqueous solution and maintain the highest adsorption capacity even after multiple adsorption and desorption cycles. Therefore, the prepared HG-cl-poly(AA) hydrogel could be a potential adsorbent for dye removal and have an admirable capacity for cleaning the aquatic environment.
Elements generating a free subgroup of rank three in the multiplicative group of a division ring
Authors: Goncalves Jairo Z. , Souza Gabriel A. L.
Published: September 2024

Let [Formula: see text] be the group algebra of a residually torsion free nilpotent group [Formula: see text] over a field [Formula: see text] of characteristic [Formula: see text]. If [Formula: see text] is any pair of noncommuting elements of [Formula: see text], we show that for any rational number [Formula: see text] with [Formula: see text], the subgroup [Formula: see text] is free of rank [Formula: see text] in the Malcev–Neumann field of fractions of [Formula: see text]. This result comes from a method of producing free groups of rank three in rational quaternions. In general, if a division ring [Formula: see text] has dimension [Formula: see text] over its center [Formula: see text], and if the transcendence degree of [Formula: see text] over its prime field [Formula: see text] is [Formula: see text], we present a method to construct free subgroups of rank three.
Case 333
Authors: Krishnan Venkatram , Rana Abhilasha , Nix James , Damalcheruvu Prashanth
Published: September 2024

History

A 61-year-old male patient without prior history of ophthalmologic problems presented with pain and redness in the left eye associated with slowly progressive proptosis over the previous 6 months. The patient also had diplopia in rightward and downward gaze. There was no vision loss. Mild fullness was seen in the periorbital tissues without any redness or fluctuance and with no purulent discharge from the left eye. The patient was otherwise healthy, with a 6-year history of diabetes mellitus and an 8-year history of hypertension managed well with medication. There was no history of trauma to the head or face. At clinical examination, conjunctival edema and redness with proptosis were noted. The cornea was clear. Evaluation of eye movements revealed restricted motion of the left eye in medial gaze and downward gaze. Ophthalmoscopic evaluation did not show any substantial abnormality. The retina and retinal vascularity were unremarkable. The right eye was unremarkable. Uncorrected visual acuity was 20/30 in the right eye and 20/40 in the left eye. Corrected visual acuity was 20/20 in both eyes. Complete blood cell count, as well as liver and kidney function test results, were within normal limits. The erythrocyte sedimentation rate and C-reactive protein level were normal. Thyroid function test results were normal. The patient subsequently underwent CT of the orbits without and with contrast enhancement ( Fig 1 ) followed by further evaluation with MRI of the orbits without and with contrast enhancement ( Figs 2 – 4 ).
Photon-counting Detector CT for Liver Fat Quantification: Validation across Protocols in Metabolic Dysfunction–associated Steatotic Liver Disease
Authors: Lin Huimin , Xu Xinxin , Deng Rong , Xu Zhihan , Cai Xinxin , Dong Haipeng , Yan Fuhua
Published: September 2024

This study validated the use of photon-counting detector CT for accurate, protocol-independent liver fat quantification in metabolic dysfunction–associated steatotic liver disease across various imaging settings.
AHCC inhibited hepatic stellate cells activation by regulation of cytoglobin induction via TLR2-SAPK/JNK pathway and collagen production via TLR4-NF-κβ pathway
Authors: Urushima Hayato , Matsubara Tsutomu , Qiongya Gu , Daikoku Atsuko , Takayama Misako , Kadono Chiho , Nakai Hikaru , Ikeya Yukinobu , Yuasa Hideto , Ikeda Kazuo
Published: September 2024

AHCC, a standardized extract of cultured Lentinula edodes mycelia, suppresses liver fibrosis progression by induction of cytoglobin via the Toll-like receptor 2 (TLR2)-stress-activated protein kinase/Jun NH2-terminal kinase (SAPK/JNK) pathway and the inhibition of collagen production via the TLR4-NFκβ pathway in hepatic stellate cells. Daily oral administration of AHCC from the stage of MASLD may have the potential to prevent disease progression to MASH with fibrosis.