bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermodynamic Design and Analysis of Steam Rankine Cycle for Nuclear Fusion Application
Authors: Thanganadar Dhinesh , Acres Jack 
Published: August 2024

Abstract
Generating electricity from nuclear fusion is a promising renewable energy source in the medium to long term. The UK Atomic Energy Authority (UKAEA) is developing a commercial fusion reactor, namely Spherical Tokamak for Energy Production (STEP), with the ambition of building a prototype power plant able to deliver a target 100 MW net electricity to the grid by 2040. This infers that the power cycle has to produce &gt; 700 MW electricity to meet the in-house parasitic load. The magnetically confined fusion reactor delivers heat which will be carried by the coolant to the power cycle, where the heat is converted to electricity. Designing a power cycle for a fusion application has its own challenges owing to the requirement of 1) accepting heat at multiple temperature levels, 2) able to cope with fast transient operation, 3) efficiently integrate low grade-heat received from high heat flux plasma facing in-vessel components, and 4) offer high thermodynamic conversion efficiency to overcome the high parasitic load of fusion reactor. Different closed-loop power cycle options are possible including Rankine or Brayton cycles and this paper describes a potential steam Rankine cycle design meeting the steady-state requirements of the fusion reactor.
Design and Simulation of a Blowdown Facility for Supercritical Carbon Dioxide
Authors: Ghavami Mohsen , White Martin T. , Chibli Hicham , Sayma Abdulnaser I. 
Published: August 2024

Abstract
This paper describes an experimental blowdown facility designed to characterise the expansion of supercritical CO2 near the critical point. Specifically, the test rig aims at replicating the expansion process at the leading edge of a CO2 compressor with the goal of studying the role of real-gas effects, and possible condensation. The test rig consists of two pressure vessels (high and low pressure), a reciprocating compressor used for charging, a temperature-controlled water circuit to adjust the temperature of the high-pressure tank and a test section comprised of a convergent-divergent nozzle.
The specification of the pressure vessels and the recharging compressor is described which are selected to allow for reasonable charging and blowdown times. The design of a thermal management system is also described that keeps the conditions within the high-pressure vessel temperature within the desired range, whilst avoiding over pressurisation. The optimisation of the test rig layout is also discussed which includes identifying an economically and technically viable solution for the positioning of pressure relief valves and the ventilation system. Furthermore, the range of anticipated test conditions that can be achieved and the expected expansion process within the nozzle have been explored using transient lumped mass models of pressure vessels that are coupled with a quasi-steady nozzle model to determine the expected conditions within the nozzle. The nozzle model assumes a homogeneous mixture under thermal equilibrium at any point where the working fluid enters the saturation dome.
For the defined test rig specifications (high pressure tank = 0.1 m3; low pressure tank = 0.185 m3; CO2 charge = 100 kg; nozzle throat = 100 mm2) it is predicated that constant inlet pressure conditions can be sustained for between 0.4 and 5.5 seconds for test section inlet conditions ranging between 27 and 45 °C, and 70 and 90 bar.
Performance Characterization of a Radial Rotating Detonation Combustor With Axial Exhaust
Authors: Langner Dalton , Gupta Apurav , James Ashley , Agrawal Ajay K. 
Published: August 2024

Abstract
This experimental study characterizes the performance of a radial rotating detonation combustor (RDC). An aerospike nozzle for rocket propulsion has been integrated into the center of the combustor, although the same combustor could also be coupled with turbomachinery. The radial RDC utilized a rapid to gradual (RTG) area change in the flow direction to effectively confine the detonation region close to the inlet plane and to improve the uniformity of the flow exiting the RDC. Three test cases were analyzed, (a) a baseline case at a total reactant mass flow rate, ṁ = 0.136 kg/s and equivalence ratio, ϕ = 0.6, (b) a higher reactant flow rate, ṁ = 0.318 kg/s and ϕ = 0.6, and (c) a higher ϕ = 0.8 at ṁ = 0.318 kg/s. All tests were conducted using methane and a 67% oxygen and 33% nitrogen (by mole) oxidizer mixture. Measurements were acquired using CTAP probes inside the combustion channel and along the aerospike to characterize the performance, PCB and ion probes near the detonation region to identify wave modes and their variations during the test, and thrust measurements using a six-axis force sensor. Results show highly complex wave modes with multiple co-rotating and/or counter-rotating waves depending upon the reactant flow rate. The pressure and thrust measurements are consistent with the wave mode analysis. In general, a positive (combustor only) pressure gain was inferred when losses associated with the injection system were excluded. The study highlights the challenges associated with fuel-air mixing and integrating the RDC with downstream hardware.
Cracking Behavior of Environmental Barrier Coatings/CMC System Using Acoustic Emission and Digital Image Correlation
Authors: Panakarajupally Ragavendra Prasad , Morscher Gregory N. , Shi Jun 
Published: August 2024

Abstract
An investigation into the cracking behavior of advanced environmental barrier coating / woven SiC/SiC ceramic matrix composite (CMC) system under uniaxial tension testing was performed in this study. The effect of substrate (CMC) condition on the coating behavior was also studied. Acoustic emission (AE) and digital image correlation (DIC) were implemented as health monitoring techniques to gain detailed insights into the fracture process of the coating and to identify the origin and location of the fracture events. Fluorescent penetrant inspection was used in-situ in some cases to help identify cracks. Post-test microscopy was performed to correlate the results with DIC and AE. It was evident that for the as-produced woven substrate, the EBC coating cracked prior to substrate cracking; however, for the altered surface substrate, the CMC substrate formed matrix cracks prior to the EBC coating.
Unsteady Flow Mechanism of Corner Separation Control Using Blade End Slots in a Highly Loaded Compressor Cascade
Authors: Liu Yangwei , Zhong Weibo , Tang Yumeng 
Published: August 2024

Abstract
Blade end slots has been proved to be an effective method to suppress the corner separation, thereby improving the aerodynamic performance of compressor. The unsteady effects of blade end slots affiliated with a highly-loaded compressor cascade on corner separation control are investigated based on delayed detached eddy simulation under the Mach number of 0.59. The corner separation vortex structures between the datum blade and the end slotted blade are compared. The vortex topologies are markedly reorganized and suppressed by the blade end slots. Unsteady flow behaviors of separation vortex and the corresponding dynamic mechanisms are analyzed in both time and frequency domains. The interaction of the self-adaptive jet flow from the blade end slots to the corner separation flow results in smaller-scale vortices in the blade end region with a higher characteristic frequency. Consequently, the unsteady effects caused by corner separation vortices are significantly reduced in range and intensity through the enhancement of flow mixing and the rapid dissipation of corner separation vortices into larger-scale lower-frequency features. Furthermore, spatiotemporal features and dynamics of corner separation flow with blade end slot control are investigated using the enhanced dynamic mode decomposition method. Results show that the dominant unsteady flow behavior develops with better stability, and the intermittency of low-frequency and large-scale behavior is reduced via the blade end slot control.
Thermohydraulic Performance Analysis in Square Duct Featuring Novel High-Performance Broken Ribs and Ribs With Fins for High Reynolds Number Gas Turbine Blade Internal Cooling
Authors: Pandya Naimish , Ekkad Srinath V. 
Published: August 2024

Abstract
This study investigates the thermal-hydraulic performance of novel rib configurations, specifically novel V-shaped broken ribs, and V-shaped ribs with fins, within a square channel for significantly high Reynolds number conditions. The Reynolds-averaged Navier-Stokes (RANS) equations are solved utilizing the ANSYS Fluent 2022 R2 solver with the realizable version of the k-ε RNG turbulence model. Computational simulations cover a Reynolds number range from 100,000 to 500,000 while maintaining various dimensions for ribs and fins relative to the channel hydraulic diameter (Dh). The conventional V-shaped rib configuration data from the previous experiment has been used to validate the numerical model for this study. The V-shaped ribs with fins exhibit higher heat transfer enhancement surpassing V-shaped broken ribs by 13% at Reynolds of 300,000. More importantly novel V-shaped ribs with fins and V-shaped broken ribs geometry do not show significant heat transfer degradation when the Reynolds number increases from 100,000 to 500,000. This study offers valuable insights for optimizing rib geometry concurrently to enhance hydraulic and thermal performance for extremely high Reynolds number conditions (&gt; 90,000).
Are There Sex Differences in Anaerobic Performance Following a Dynamic Warm-Up? A Randomized, Counterbalanced, and Crossover Design Study
Authors: Fulawka Kara , Schleper Alexander , Forsyth Lucas , Scribbans Trisha , Anzalone Robert , Villar Rodrigo 
Published: August 2024

The increasing trend of females participating in elite and historically male-dominated sports has also resulted in a rise in females performing dynamic warm-ups (DWs). DW is a widely used practice in hockey. However, there is scarce evidence describing how DWs impact subsequent anaerobic performance and whether this response differs between sexes. This study aimed to determine sex differences in anaerobic performance when preceded by a DW. Twenty National Collegiate Athletics Association Division-II hockey players (n = 20, 10 female) completed a Wingate Anaerobic Test (WAnT) preceded by a DW or no warm-up in a randomized, counterbalanced order and followed a crossover design. The DW was ∼8 min long and consisted of 13 movements that targeted prime muscles and joints involved in ice skating. The WAnT consisted of a 30-s, maximal effort sprint against 7.5% of the participant’s body mass performed on a cycle ergometer. Peak power output (PPO), relative peak power (RPP), mean anaerobic power (MP), and fatigue index (FI) evaluated anaerobic performance during the WAnT. There were no significant differences between male and female scores following DW. MP was significantly higher in males and females, but PPO, RPP, and FI were not when a DW preceded the WAnT. In both conditions, males had higher PPO and MP than females, while there were no sex differences in RPP and FI. In conclusion, performing a DW before a WAnT improved MP for females and males with no adverse effects on PPO, RPP, and FI. This study suggests that DW might benefit hockey players independently of sex.
Adjuvants restore colistin sensitivity in mouse models of highly colistin-resistant isolates, limiting bacterial proliferation and dissemination
Authors: Koller Beverly H. , Jania Leigh A. , Li Haoting , Barker William T. , Melander Roberta J. , Melander Christian 
Published: August 2024

ABSTRACT

Antimicrobial resistance (AMR) has led to a marked reduction in the effectiveness of many antibiotics, representing a substantial and escalating concern for global health. Particularly alarming is resistance in Gram-negative bacteria due to the scarcity of therapeutic options for treating infections caused by these pathogens. This challenge is further compounded by the rising incidence of resistance to colistin, an antibiotic traditionally considered a last resort for the treatment of multi-drug resistant (MDR) Gram-negative bacterial infections. In this study, we demonstrate that adjuvants restore colistin sensitivity
in vivo
. We previously reported that the salicylanilide kinase inhibitor IMD-0354, which was originally developed to inhibit the human kinase IKKβ in the NFκB pathway, is a potent colistin adjuvant. Subsequent analog synthesis using an amide isostere approach led to the creation of a series of novel benzimidazole compounds with enhanced colistin adjuvant activity. Herein, we demonstrate that both IMD-0354 and a lead benzimidazole effectively restore colistin susceptibility in mouse models of highly colistin-resistant
Klebsiella pneumoniae
and
Acinetobacter baumannii
-induced peritonitis. These novel adjuvants show low toxicity
in vivo
, significantly reduce bacterial load, and prevent dissemination that could otherwise result in systemic infection.
The novel MFS efflux pump SxtP, regulated by the LysR-type transcriptional activator SxtR, is involved in the susceptibility to sulfamethoxazole/trimethoprim (SXT) and the pathogenesis of
Acinetobacter baumannii
Authors: Gaona Marc , Corral Jordi , Campoy Susana , Barbé Jordi , Pérez−Varela María , Aranda Jesús 
Published: August 2024

ABSTRACT

Acinetobacter baumannii
is a notorious opportunistic pathogen responsible for healthcare-associated infections worldwide. Efflux pumps play crucial roles in mediating antimicrobial resistance, motility, and virulence. In this study, we present the identification and characterization of the new
A. baumannii
efflux pump SxtP belonging to the MFS superfamily (
m
ajor
f
acilitator
s
uperfamily), along with its associated activator
L
ysR
-
type
t
ranscriptional
r
egulator (LTTR) SxtR, demonstrating their roles in sulfamethoxazole/trimethoprim (also known as co-trimoxazole or SXT) resistance, surface-associated motility and virulence.
Retrospective validation study of a machine learning-based software for empirical and organism-targeted antibiotic therapy selection
Authors: Tejeda Maria Isabel , Fernández Javier , Valledor Pablo , Almirall Cristina , Barberán José , Romero-Brufau Santiago 
Published: August 2024

ABSTRACT

Errors in antibiotic prescriptions are frequent, often resulting from the inadequate coverage of the infection-causative microorganism. The efficacy of iAST, a machine-learning-based software offering empirical and organism-targeted antibiotic recommendations, was assessed. The study was conducted in a 12-hospital Spanish institution. After model fine-tuning with 27,531 historical antibiograms, 325 consecutive patients with acute infections were selected for retrospective validation. The primary endpoint was comparing each of the top three of iAST’s antibiotic recommendations’ success rates (confirmed by antibiogram results) with the antibiotic prescribed by the physicians. Secondary endpoints included examining the same hypothesis within specific study population subgroups and assessing antibiotic stewardship by comparing the percentage of antibiotics recommended that belonged to different World Health Organization AWaRe groups within each arm of the study. All of iAST first three recommendations were non-inferior to doctor prescription in the primary endpoint analysis population as well as the secondary endpoint. The overall success rate of doctors’ empirical treatment was 68.93%, while that of the first three iAST options was 91.06% (
P
< 0.001), 90.63% (
P
< 0.001), and 91.06% (
P
< 001), respectively. For organism-targeted therapy, the doctor’s overall success rate was 84.16%, and that of the first three ranked iAST options was 97.83% (
P
< 0.001), 94.09% (
P
< 0.001), and 91.30% (
P
< 0.001), respectively. In empirical therapy, compared to physician prescriptions, iAST demonstrated a greater propensity to recommend access antibiotics, fewer watch antibiotics, and higher reserve antibiotics. In organism-targeted therapy, iAST advised a higher utilization of access antibiotics. The present study demonstrates iAST accuracy in predicting antibiotic susceptibility, showcasing its potential to promote effective antibiotic stewardship.

CLINICAL TRIALS

This study is registered with

ClinicalTrials.gov
as
NCT06174519

.
Application of machine-learning models to predict the ganciclovir and valganciclovir exposure in children using a limited sampling strategy
Authors: Ponthier Laure , Franck Bénédicte , Autmizguine Julie , Labriffe Marc , Ovetchkine Philippe , Marquet Pierre , Åsberg Anders , Woillard Jean-Baptiste 
Published: August 2024

ABSTRACT

Intravenous ganciclovir and oral valganciclovir display significant variability in ganciclovir pharmacokinetics, particularly in children. Therapeutic drug monitoring currently relies on the area under the concentration-time (AUC). Machine-learning (ML) algorithms represent an interesting alternative to Maximum-a-Posteriori Bayesian-estimators for AUC estimation. The goal of our study was to develop and validate an ML-based limited sampling strategy (LSS) approach to determine ganciclovir AUC
0–24
after administration of either intravenous ganciclovir or oral valganciclovir in children. Pharmacokinetic parameters from four published population pharmacokinetic models, in addition to the World Health Organization growth curve for children, were used in the mrgsolve R package to simulate 10,800 pharmacokinetic profiles of children. Different ML algorithms were trained to predict AUC
0–24
based on different combinations of two or three samples. Performances were evaluated in a simulated test set and in an external data set of real patients. The best estimation performances in the test set were obtained with the Xgboost algorithm using a 2 and 6 hours post dose LSS for oral valganciclovir (relative mean prediction error [rMPE] = 0.4% and relative root mean square error [rRMSE] = 5.7%) and 0 and 2 hours post dose LSS for intravenous ganciclovir (rMPE = 0.9% and rRMSE = 12.4%). In the external data set, the performance based on these two sample LSS was acceptable: rMPE = 0.2% and rRMSE = 16.5% for valganciclovir and rMPE = −9.7% and rRMSE = 17.2% for intravenous ganciclovir. The Xgboost algorithm developed resulted in a clinically relevant individual estimation using only two blood samples. This will improve the implementation of AUC-targeted ganciclovir therapeutic drug monitoring in children.
Analytical and clinical validation of direct detection of antimicrobial resistance markers by plasma microbial cell-free DNA sequencing
Authors: Christians Fred C. , Akhund-Zade Jamilla , Jarman Kristin , Venkatasubrahmanyam Shivkumar , Noll Nicholas , Blauwkamp Timothy A. , Bercovici Sivan , Zielinska Aga , Carr Amy L. , Craney Arryn , Pike Matthew , Farrell John Joseph , Dadwal Sanjeet , Wood James B. , Matkovich Efrat , McAdams Staci , Nolte Frederick S. 
Published: August 2024

ABSTRACT

Sequencing of plasma microbial cell-free DNA (mcfDNA) has gained increased acceptance as a valuable adjunct to standard-of-care testing for diagnosis of infections throughout the body. Here, we report the analytical and clinical validation of a novel application of mcfDNA sequencing, the non-invasive detection of seven common antimicrobial resistance (AMR) genetic markers in 18 important pathogens. The AMR markers include SCC
mec
,
mecA, mecC
,
vanA, vanB
,
bla
CTX-M
, and
bla
KPC
. The AMR markers were computationally linked to the pathogens detected. Analytical validation showed high reproducibility (100%), inclusivity (54 to 100%), and exclusivity (100%). Clinical accuracy was assessed with 114 unique plasma samples from patients at seven study sites with concordant culture results for target bacteria from a variety of specimen types and correlated with available phenotypic antimicrobial susceptibility test results and genotypic results. The positive percent agreement (PPA), negative percent agreement (NPA), and diagnostic yield (DY) were estimated for each AMR marker. DY was defined as the percentage of tests that yielded an actionable result of either detected or not detected. The results for the combination of SCC
mec
and
mecA
for staphylococci were PPA 19/20 (95.0%), NPA 21/22 (95.4%), DY 42/60 (70.0%);
vanA
for enterococci were PPA 3/3 (100%), NPA 2/2 (100%), DY 5/6 (83.3%);
bla
CTX-M
for gram-negative bacilli were PPA 5/6 (83.3%), NPA 29/29 (100%), DY 35/49 (71.4%); and
bla
KPC
for gram-negative bacilli were PPA 0/2 (0%), NPA: 23/23 (100%), DY 25/44 (56.8%). The addition of AMR capability to plasma mcfDNA sequencing should provide clinicians with an effective new culture-independent tool for optimization of therapy.

IMPORTANCE
This manuscript is ideally suited for the Innovative Diagnostic Methods sections as it reports the analytical and clinical validation of a novel application of plasma microbial cell-free DNA sequencing for direct detection of seven selected antimicrobial resistance markers in 18 target pathogens. Clearly, it has potential clinical utility in optimizing therapy and was incorporated into the Karius test workflow in September 2023. In addition, the workflow could readily be adapted to expand the number of target bacteria and antimicrobial resistance markers as needed.
Comparison of the sensitivity and specificity of commercial anti-dengue virus IgG tests to identify persons eligible for dengue vaccination
Authors: Medina Freddy A. , Vila Frances , Adams Laura E. , Cardona Jaime , Carrion Jessica , Lamirande Elaine , Acosta Luz N. , De León-Rodríguez Carlos M. , Beltran Manuela , Grau Demian , Rivera-Amill Vanessa , Balmaseda Angel , Harris Eva , Madewell Zachary J. , Waterman Stephen H. , Paz-Bailey Gabriela , Whitehead Stephen , Muñoz-Jordán Jorge L. 
Published: August 2024

ABSTRACT

The Advisory Committee on Immunization Practices (ACIP) recommended that dengue pre-vaccination screening tests for Dengvaxia administration have at least 98% specificity and 75% sensitivity. This study evaluates the performance of commercial anti-DENV IgG tests to identify tests that could be used for pre-vaccination screening. First, for seven tests, we evaluated sensitivity and specificity in early convalescent dengue virus (DENV) infection, using 44 samples collected 7–30 days after symptom onset and confirmed by RT-PCR. Next, for the five best-performing tests and two additional tests (with and without an external test reader) that became available later, we evaluated performance to detect past dengue infection among a panel of 44 specimens collected in 2018–2019 from healthy 9- to 16-year-old children from Puerto Rico. Finally, a full-scale evaluation was done with the four best-performing tests using 400 specimens from the same population. We used virus focus reduction neutralization test and an in-house DENV IgG ELISA as reference standards. Of seven tests, five showed ≥75% sensitivity in detecting anti-DENV IgG in early convalescent specimens with low cross-reactivity to the Zika virus. For the detection of previous DENV infections, the tests with the highest performance were the Euroimmun NS1 IgG ELISA (sensitivity 84.5%, specificity 97.1%) and CTK Dengue IgG rapid test R0065C with the test reader (sensitivity 76.2% specificity 98.1%). There are IgG tests available that can be used to accurately classify individuals with previous DENV infection as eligible for dengue vaccination to support safe vaccine implementation.

IMPORTANCE
The Advisory Committee on Immunization Practices (ACIP) has set forth recommendations that dengue pre-vaccination screening tests must exhibit at least 98% specificity and 75% sensitivity. Our research rigorously assesses the performance of various commercial tests against these benchmarks using well-characterized specimens from Puerto Rico. The findings from our study are particularly relevant given FDA approval and ACIP recommendation of Sanofi Pasteur’s Dengvaxia vaccine, highlighting the need for accurate pre-vaccination screening tools.