bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mean‐field limit of 2D stationary particle systems with signed Coulombian interactions
Authors: Peszek Jan , Rodiac Rémy 
Published: January 2025

AbstractWe study the mean‐field limits of critical points of interaction energies with Coulombian singularity. An important feature of our setting is that we allow interaction between particles of opposite signs. Particles of opposite signs attract each other whereas particles of the same signs repel each other. In two dimensional, we prove that the associated empirical measures converge to a limiting measure that satisfies a two‐fold criticality condition: in velocity form or in vorticity form. Our setting includes the stationary attraction–repulsion problem with Coulombian singularity and the stationary system of point vortices in fluid mechanics. In this last context, in the case where the limiting measure is in , we recover the classical criticality condition stating that , with , is a stationary solution of the incompressible Euler equation. This result, is, to the best of our knowledge, new in the case of particles with different signs (for particles of the positive sign, it was obtained by Schochet in 1996). In order to derive the limiting criticality condition in the velocity form, we follow an approach devised by Sandier–Serfaty in the context of Ginzburg–Landau vortices. This consists of passing to the limit in the stress‐energy tensor associated with the velocity field. On the other hand, the criticality condition in the vorticity form is obtained by arguments closer to the ones of Schochet.
Operation of a Compression Ignition Engine at Idling Load Under Simulated Cold Weather Conditions
Authors: Dev Shouvik , Guo Hongsheng , Liko Brian , Lafrance Simon 
Published: January 2025

Abstract
Heavy-duty compression ignition (CI) engines can be subject to long periods of idling during their duty cycles. In colder climates, getting the engine and exhaust aftertreatment (EAT) system to ideal operating temperatures can be challenging under such idling and low load conditions. This may lead to high emissions of criteria pollutants especially nitrogen oxides (NOx). Increasing the engine load and idling speed may help mitigate NOx emissions but typically leads to higher greenhouse gas emissions. Therefore, the objective of this study is to evaluate the performance of a heavy-duty CI engine operating at various idling conditions and determine suitability for exhaust aftertreatment system operation. Tests are conducted on a heavy-duty single cylinder CI research engine fueled with diesel. As per the United States' (U.S.) Code of Federal Regulations (CFR), CI engines can be certified for the optional Clean Idle NOx emission standard. A corresponding two-mode Clean Idle Test (CIT) is specified in CFR which requires the engine to be operating in fully warmed-up condition at two engine speeds. Steady-state tests are conducted at these two engine speeds of 650 and 1100 rpm, and cold weather operation is simulated by operating the engine at suboptimal coolant, lubricant, and intake air temperatures. The steady-state tests are used to determine suitable diesel injection timing for performing the CIT under standard and simulated cold weather conditions. At the lowest load and 650 rpm idling speed, use of multiple injections and exhaust gas recirculation (EGR) are insufficient for raising the exhaust gas temperature above 200 °C. A combination of higher load, EGR, and 1100 rpm idling speed can create conditions for light-off selective catalytic reduction (LO-SCR) operation at the expense of higher fuel consumption. The modified CIT results show that the optional Clean Idle NOx emission standards can be met with the use of EGR at both test modes. The mode 2 conditions at 1100 rpm may allow LO-SCR activation as well. There are also distinct differences between results under fully and partially warmed-up conditions.
Material Lateral Position Guiding During Calendering Process Via Material Width Change Modeling and Model Predictive Control
Authors: Chen Haozhen , Ni Jun , Lou Yangbing 
Published: January 2025

Abstract
One of important control problems in calendering system is the web lateral position control: during calendering, the web deforms with a reduction of thickness and an expansion in width, this leads to potential lateral position deviation, especially when the web is not flat. This problem sometimes causes quality issues, hence, precise modeling and control need to be developed. This paper focuses on the web lateral position guiding by modeling and controlling a calendering system: a modeling method and a corresponding model predictive control are proposed. The study is based on electrode web calendering for Li-ion battery production and is supported by data collected from experiments on an industrial-scale winding machine.
Elastostatic Performance Evaluation of a Full-Mobility Parallel-Kinematics Machine With Flexible Links
Authors: Sun Qi , Angeles Jorge 
Published: January 2025

Abstract
The subject of this article is the elastostatics of a novel three-limb, full-mobility parallel-kinematics machine (PKM) with flexible links, intended for high-frequency, small-amplitude operations. The objective is to establish the Cartesian stiffness model and performance indices capable of guiding the structural design of the machines of interest. We base our analysis on what we term an elastostatic Cartesian model: the light-weight limb rods are modeled as identical, massless, linearly elastic beams; the motor shafts and couplings are modeled likewise, with the beams replaced by identical, massless, linearly elastic torsional springs, both link flexibility and actuator flexibility thus being considered. The moving platform is assumed to be the only moving rigid body of the machine. This platform is thus regarded as a rigid body elastically mounted onto the base platform via a six-degree-of-freedom (six-DoF) Cartesian spring. Then, the PKM 6×6 Cartesian stiffness matrix, considering the flexibility of both limb rods and motor shafts, is derived via the pertinent kinetostatic relations. Moreover, three alternative indices are defined from this model to evaluate the robot stiffness, which allows us to choose the most appropriate one for specific applications.
Active Cables Selection for Collocated Vibration Control of Small-Sized Overconstrained Cable-Driven Parallel Robots
Authors: Garcia Thibault , Rémond Didier , Chesné Simon 
Published: January 2025

Abstract
Cable-driven parallel robots (CDPRs) are well appreciated for high dynamics applications, due to their lightweights moving parts. Nevertheless, due to the low stiffness of cables, vibrations can occur and can degrade performances if high precision is required, such as in additive manufacturing for instance. Previous works have studied techniques to counteract vibrations, like using motor command or embedded devices. Based on a previous first exploration of using piezoelectric transducers on cables for this type of robot, this paper presents a proper formulation of the collocated active vibration control to damp the end-effector oscillations of small-sized overconstrained CDPRs by the measure of the variation in cable tensions. This goes through a modeling of such a robot with embedded piezoelectric transducers under appropriate assumptions. From this control formulation, it is shown that the collocated nature of these transducers are fundamental. It is thus possible to highlight an energetic index of active cables selection, regardless of the used control law. The proposed technique is developed theoretically and analyzed through simulations on an eight-cable robot.
Construction of Confidence Regions for Uncertain Spatial Displacements With Dual Rodrigues Parameters
Authors: Yu Zihan , Ge Qiaode Jeffrey , Langer Mark P. 
Published: January 2025

Abstract
This article follows our recent work on the computation of kinematic confidence regions from a given set of uncertain spatial displacements with specified confidence levels. Dual quaternion algebra is used to compute the mean displacement as well as relative displacements from the mean. In constructing a 6D confidence ellipsoid, however, we use dual Rodrigues parameters resulting from dual quaternions. The advantages of using dual quaternions and dual Rodrigues parameters are discussed in comparison with those of three translation parameters and three Euler angles, which were used for the development of the so-called rotational and translational confidence limit (RTCL) method. The set of six dual Rodrigues parameters are used to define a parametric space in which a 6×6 covariance matrix and a 6D confidence ellipsoid are obtained. An inverse operation is then applied to first obtain dual quaternions and then to recover the rotation matrix and translation vector for each point on the 6D ellipsoid. Through examples, we demonstrate the efficacy of our approach by comparing it with the RTCL method known in literature. Our findings indicate that our method, based on the dual Rodrigues formulation, yields more compact and effective swept volumes than the RTCL method, particularly in cases involving screw displacements.
Numerical Study on the Effect of Various Working Fluids on the Performance of Loop Heat Pipes Based on Two-Dimensional Simulation
Authors: Shao Bo , Lin Bingyao , Li Nanxi , Liu Le , Jiang Zhenhua , Dong Deping , Wu Yinong 
Published: January 2025

Abstract
The computational fluid dynamics (CFD) method is often used to study heat and mass transfer mechanisms in loop heat pipes (LHPs). However, few numerical studies have been conducted on the entire loop heat pipe system. In this work, a two-dimensional simulation model of an LHP was developed. The wicking process was described using a capillary pressure model, implemented through user-defined functions (UDFs). The flow, phase change, and heat transfer processes vary with the change of the working fluid. Therefore, the effects of ammonia, propylene, and R245fa on the heat transfer performance of the LHP were analyzed in the simulation. According to the simulation results, the LHP charged with ammonia showed the best heat transfer performance, followed by the LHP charged with propylene, and the LHP charged with R245fa showed the worst heat transfer performance. The simulation results align with the predictions from figures of merit (FOMs). Moreover, the model provides detailed insights into the temperature field and vapor–liquid distribution during LHP operation. Experiments using an LHP with the three working fluids were also conducted to verify the model's accuracy. Regarding the influence of the working fluid and the heat load on LHP performance, the simulation model aligns with the experimental results.
Evaluation of Particulate Deposition Effects on Film Cooling Using Conjugate Heat Transfer Methods: An Experimental and Numerical Study
Authors: Yang Xing , Hao Zihan , Feng Zhenping 
Published: January 2025

Abstract
A significant challenge of offering adequate film cooling for gas turbine hot components in practical operation is deposition induced by impurities from the intake air and fuel, which influences the overall cooling performance by changing the surface geometric and thermal conditions. In this study, an experimental and numerical combined methodology was used to evaluate the deposition effects on film cooling from a row of holes on conductive flat plates. Cylindrical holes with simple and compound holes that are extensively used in today's modern engines were investigated to assess the sensitivity of their overall cooling effectiveness to deposition for coolant injection ratios of 0.5–2.0. Flow physics and thermal fields were analyzed to better understand the coupling effects of film cooling with deposition and their interaction with solid walls. Furthermore, the isolated effects of deposition on adiabatic film cooling and heat transfer were examined, allowing for a better understanding of which factor dominates the resulting combined effects. Inspection of overall cooling effectiveness on the wall backside revealed that the deposition effects were strongly linked to coolant jet behaviors, which were determined by both the coolant injection ratio and the hole orientation angle. Quantitative comparisons showed that deposition decreased overall cooling effectiveness by 22% on the flat plate cooled by the compound-angled hole with the lowest blowing ratio of 0.5, while it increased overall cooling effectiveness from the simple hole by 38% at a higher blowing ratio of 1.5. The results reported for the current work provide guidance on how to choose orientation angles for film cooling design where deposition problems are accounted for.
Parametric Study and Optimization of a New Type of Solar Air Collector Employing Flat Micro Heat Pipe Arrays
Authors: Wang Xinran , Diao Yanhua , Wang Zhen , Pan Yawen , Zhao Yaohua , Li Yuhan , Wang Tengyue , Zhu Tingting 
Published: January 2025

Abstract
The performance improvement of flat-plate solar air collectors (FPSACs) is vital for solar energy utilization. Accordingly, flat micro heat pipe arrays (FMHPAs) have been utilized in FPSACs given their excellent thermal conductivity and suitable specific surface area. To investigate the impact of structural parameters of the flat-plate solar air collector with flat micro heat pipe arrays and optimize the performance, this study establishes a CFD 3D model of the collector with L-shaped flat micro heat pipe arrays. Fin height H, fin spacing L, glass thickness D, and air gap thickness Sair are selected as four important structural parameters for numerical work. Response surface methodology is adopted to recognize the significance of each factor and realize the prediction and optimization of the collector's thermal efficiency. Results show that the thermal efficiency can achieve a peak value of 52.50%. An enhanced heat transfer condition in condensation is obtained when the optimal fin height and fin spacing are 25 and 4 mm, respectively. Improved thermal insulation in evaporation is also achieved when the optimal glass thickness and air gap thickness are 3 and 35 mm, respectively. The significance order of the factors is H &gt; L &gt; D &gt; Sair. The results can serve as an important reference for designing the flat-plate solar air collectors.
Genetic investigation of hydrogenases in
Thermoanaerobacterium thermosaccharolyticum
suggests that redox balance via hydrogen cycling enables high ethanol yield
Authors: de Souza Layse C. , Herring Christopher D. , Lynd Lee R. 
Published: January 2025

ABSTRACT

Thermoanaerobacterium thermosaccharolyticum
is an anaerobic and thermophilic bacterium that has been genetically engineered for ethanol production at very high yields. However, the underlying reactions responsible for electron flow, redox equilibrium, and how they relate to ethanol production in this microbe are not fully elucidated. Therefore, we performed a series of genetic manipulations to investigate the contribution of hydrogenase genes to high ethanol yield, generating evidence for the importance of hydrogen-reacting enzymes in ethanol production. Our results indicate that a high ethanol yield, >85% of the theoretical maximum, only occurs when the
hfsD, hydAB
, and
nfnAB
genes are all present together, while the
hfsB
gene is absent. We propose that the products of these three gene clusters facilitate an NADPH-generating reaction via hydrogen cycling, with a stoichiometry comparable with a canonical ferredoxin:NADP
+
oxidoreductase (FNOR; EC 1.18.1.2) reaction. The hypothesized mechanism provides a balance of nicotinamide cofactors and facilitates ferredoxin recycling, leading to progress in optimizing the energy conversion of biomass-derived sugars to ethanol.

IMPORTANCE
Our study elucidates the crucial role of electron flow and redox balancing mechanisms in improving ethanol yields from renewable biomass. We delve into the mechanism of electron transfer, highlighting the potential of key genes to be leveraged for enhanced ethanol production in anaerobic microbial species. We suggest by genetic investigation the existence of a novel Ferredoxin:NADP+ Oxidoreductase (FNOR) reaction, comprising HfsD, HydAB, and NfnAB enzymes, as a promising avenue for achieving balanced stoichiometry and efficient ethanol synthesis. Our findings not only advance the understanding of microbial metabolism but also offer practical insights for developing strategies to improve bioenergy production and sustainability.
Leptospira
biofilms: implications for survival, transmission, and disease management
Authors: Dias Carla Silva , Pinna Melissa Hanzen 
Published: January 2025

ABSTRACT

Leptospirosis is a zoonotic disease caused by
Leptospira
bacteria, affecting humans and a broad range of wild and domestic animals in diverse epidemiological settings (rural, urban, and wild). The disease’s pathogenesis and epidemiology are complex networks not fully elucidated. Epidemiology reflects the One Health integrated approach of environment–animal–human interaction, causing severe illness in humans and animals, with consequent public health burdens. Saprophytic and pathogenic leptospires have been shown to form biofilms
in vivo
,
in vitro,
and in environmental samples. Biofilms are characterized by a polymeric matrix that confers protection against hostile environments (both inside and outside of the host), favoring bacterial survival and dissemination. Despite its significance, the role of this bacterial growth mode in leptospiral survival, transmission, and decreased antibiotic susceptibility remains poorly understood and underexplored. Even so, the literature indicates that biofilms might be correlated with lower antimicrobial susceptibility and chronicity in leptospirosis. In this minireview, we discuss the aspects of biofilm formation by
Leptospira
and their significance for epidemiology and therapeutic management. Understanding the current scenario provides insight into the future prospects for biofilm diagnosis, prevention, and treatment of leptospirosis.
Interaction between bacterial adhesins leads to coaggregation by the oral bacteria
Veillonella parvula
and
Streptococcus gordonii
Authors: Leo Jack C. 
Published: January 2025

ABSTRACT

Veillonella parvula
is an unusual diderm firmicute that plays a central role in the formation of dental biofilm formation through coaggregation with many other oral bacteria. However, the molecular interactions leading to oral biofilm formation are largely unknown. In a recent study (L. Dorison, N. Béchon, C. Martin-Gallausiaux, S. Chamorro-Rodriguez, et al., mBio 15:e02171-24, 2024,
https://doi.org/10.1128/mbio.02171-24
), coaggregation by
V. parvula
was shown to be mediated by trimeric autotransporter adhesins (TAAs), which are large, fibrous surface proteins widespread in Gram-negative bacteria. Importantly, this study identified the binding partner protein on a coaggregating bacterium,
Streptococcus gordonii
, which the authors called VisA. This finding is the first time a TAA mediating coaggregation with a different type of protein has been established and suggests that specifically interacting protein partners may have coevolved multiple times to allow complex biofilm formation, as exemplified by the development of dental plaque. Understanding these interactions might lead to innovations to reduce build-up of dental plaque and associated oral diseases.
Tracking clonal and plasmid transmission in colistin- and carbapenem-resistant
Klebsiella pneumoniae
Authors: Akintayo Ifeoluwa , Siroglavic Marko , Frolova Daria , Silva Mabel Budia , Grundmann Hajo , Iqbal Zamin , Budimir Ana , Reuter Sandra 
Published: January 2025

ABSTRACT

The surveillance of mobile genetic elements facilitating the spread of antimicrobial resistance genes has been challenging. Here, we tracked both clonal and plasmid transmission in colistin- and carbapenem-resistant
Klebsiella pneumoniae
using short- and long-read sequencing technologies. We observed three clonal transmissions, all containing Incompatibility group (Inc) L plasmids and New Delhi metallo-beta-lactamase
bla
NDM-1
, although not co-located on the same plasmid. One IncL-
bla
NDM-1
plasmid had been transferred between sequence type (ST) 392 and ST15, and the promiscuous IncL-
bla
OXA-48
plasmid was likely shared between a singleton and a clonal transmission of ST392. Plasmids within clonal outbreaks and between clusters and STs had 0–2 single nucleotide polymorphism (SNP) differences, showing high stability upon transfer to same or different STs. The simplest explanation, without a comprehensive analysis with long-read sequencing, would be the spread of a single common IncL-
bla
NDM-1
plasmid. However, here, we report
bla
NDM-1
in five different plasmids, emphasizing the need to investigate plasmid-mediated transmission for effective containment of outbreaks.

IMPORTANCE

Antimicrobial resistance occupies a central stage in global public health emergencies. Recently, efforts to track the genetic elements that facilitate the spread of resistance genes in plasmids outbreaks, utilizing short-read sequencing technologies, have been described. However, incomplete plasmid reconstruction from short-read sequencing data hinders full knowledge about plasmid structure, which makes the exploration very challenging. In this study, we used both short- and long-read sequencing in clinical
Klebsiella pneumoniae
from University Hospital Centre Zagreb, Croatia, which was resistant to both last-resort antibiotics colistin and carbapenem. Our results show complex transmission networks and sharing of plasmids, emphasizing multiple transmissions of plasmids harboring carbapenem and/or colistin resistance genes between and within
K. pneumoniae
clones. Only full-length sequencing plus a novel way of determining plasmid clusters resulted in the complete picture, showing how future active monitoring of plasmids as a vital tool for infection prevention and control could be implemented.