bluuebunny/crossref_metadata_2025_split huggingface dataset:
Data-Driven Prediction of Coefficient of Friction in Wet Friction Components: A Model Development and Interpretability Analysis
Authors: Wu Jianpeng , Zhao Peng , Cui Jiahao , Wang Liyong , Yang Chengbing , Ouyang Jianping 
Published: November 2024

Abstract
Predicting the coefficient of friction (COF) is essential for enhancing the efficiency and reliability of mechanical systems. Nevertheless, traditional mechanistic models relying on fixed values or fitted curves fail to accurately capture this complexity. To address this issue, this paper proposes a model for predicting the COF of wet friction components using an extreme gradient boosting (XGBoost) algorithm optimized by the sparrow search algorithm (SSA). This model effectively captures the nonlinear relationships among relative speed, pressure, temperature, and COF. As a result, the proposed SSA-XGBoost model exhibits excellent predictive performance with a root mean square error (RMSE) of only 0.063, and 88.3% of the COF predictions have a relative error of less than 1%, significantly outperforming other deep-learning algorithms. Additionally, to enhance the understanding of the COF prediction results for wet friction components, the SHapley Additive exPlanations (SHAP) model is used to explore the influence of relative speed, pressure, and temperature on the predicted COF values.
A Fully Enclosed Wave Energy Converter and Effects of Cable-Based Power Take-Off System on Power Absorption
Authors: Lu Xinrui , Han Xiao , Chen Yuan 
Published: November 2024

Abstract
Existing wave energy converters (WECs) are limited by high unit energy costs, narrow bandwidths, and vulnerability to seawater corrosion, making it difficult for wave energy to compete with solar and wind energy. This paper presents a fully enclosed WEC based on cable-driven parallel mechanisms, which absorbs energy from multiple directions to enhance the total energy absorption efficiency and bandwidth. The configuration of the inner cable-parallel mechanism (CDPM) is the key to this improved absorption efficiency. A configuration synthesis method of cable-driven parallel mechanisms is proposed to generate more configurations for the fully enclosed WEC. The motion equation of the fully enclosed WEC is derived to evaluate the power absorption performance. Moreover, a configuration synthesis method for realizing n-degrees-of-freedom (DOF) configurations in the fully-constrained CDPMs is proposed, and the configurations of these nDOF fully-constrained CDPMs with (n + 1) cables are acquired. Then, the power absorption performance under different power take-off system parameters and wave frequencies is calculated, and the effects of the CDPM configuration are investigated. The results indicate that the proposed WECs exhibit excellent performance in mean absorbed power and bandwidth. Several principles for configuration selection are provided to further improve the performance of the CDPM-based fully enclosed WEC.
Numerical Analysis of the Effect of Tunnel Hydrofoil—Stern Flap on the Motion Stability of a Double M-Craft in Regular Waves
Authors: Zhang Ziji , Li Shujiang , Ya Yu , Zhang Jianfeng , Mou Wenzheng , Jian Ranran 
Published: November 2024

Abstract
The double M-craft is a new type of high-performance multihull vessel that combines the gliding characteristics of a planing boat with the resistance-reducing characteristics of a hovercraft, but it also suffers from motion instability in regular waves. At present, there is scarce study on the effect of appendage on the motion stability of double M-craft in regular waves. By using the software star-ccm+ to numerically simulate the pitching and heaving motions of a double M-craft installed with tunnel hydrofoils and stern flaps in regular waves. Based on the overset mesh technology, the volume of fluid (VOF) method is used to capture the water–gas two-phase flow field. The 2-degree of freedom (2-DOF) motion of the rigid body is simulated by dynamic fluid-body interaction (DFBI). After investigating the effects of these combined appendages on the hydrodynamic performance, running attitude, and motion response of a double M-craft in regular waves, the optimal mounting parameters of the combined appendage have been obtained. The results have shown that all nine types of combined appendages can reduce the heave and pitch. The optimal combined appendage installation parameters include a hydrofoil longitudinal mounting position of 1/8L, an angle of attack of 3 deg, a stern flap length of 1.5%L, and a flap angle of 5 deg, which can effectively reduce the pitching response by about 8% and reduce the swaying response by about 2.6%, and enhance its longitudinal motion stability.
The Cooling Effect of Combustor Exit Louver Scheme on a Transonic Nozzle Guide Vane Endwall
Authors: Mao Shuo , Zhang Kaiyuan , Van Hout Daniel , Ng Wing F. , Xu Hongzhou , Fox Michael 
Published: November 2024

Abstract
The ever-increasing combustor exit temperature in modern turbine engine designs raises cooling challenges for the nozzle guide vane (NGV). Due to the complexity of NGV cooling design, the cooling effect from the upstream combustor cooling features can prove valuable. This study investigates, experimentally and numerically, the cooling effect of a louver cooling scheme near the combustor exit on the NGV endwall. Wind tunnel testing and computational fluid dynamics simulation are carried out with engine-representative conditions of an exit Mach number of 0.85, an exit Reynolds number of 1.5 × 106, an inlet turbulence intensity of 16%, and a density ratio of 2.1. Various coolant mass flow ratios from 1% to 4% are tested to demonstrate the effect of the coolant rate. For the geometry studied, the results found a critical mass flow ratio between 1% and 2%. When exceeding this rate, the coolant forms a uniform film, providing satisfactory coverage upstream of the NGV passage inlet. For the cooling of the NGV passage, the mass flow ratio of the range investigated is insufficient for desirable cooling performance. The pressure side endwall proves the most difficult for the coolant to reach. In addition, the fishmouth cavity at the combustor–NGV interface causes a three-dimensional cavity vortex that transports the coolant in the pitch-wise direction. The coolant transport pattern is dependent on the coolant mass flow ratio. Based on the results, the authors propose combining this louver scheme with the upstream jump cooling scheme for a desirable NGV cooling system.
Blast Mitigation Using Monolithic Closed-Cell Aluminum Foam
Authors: Dey Chitralekha , Gokhale Amol A. 
Published: November 2024

Abstract
Blast protection using cellular materials is being actively pursued at research and technology levels. The present work uniquely demonstrates the generation of stress waves, strain waves, and mass velocities in monolithic closed-cell aluminum foams of different densities and lengths, subjected to simulated blast loads, and their combined effect on blast attenuation. The foams were assumed to be resting against a rigid end wall. If the numerically calculated stress at the back face was found less than the applied stress at the front face, the interaction was termed blast mitigation or attenuation. The results show “pressure mitigation” to occur for low-density foams whose plastic strength is less than the applied pressure, but pressure amplification for high-density foams whose plastic strength is higher than the applied pressure. The pressure amplification observed in shorter-length high-density foams transformed to pressure mitigation if the foams were sufficiently long. Based on these results and other stress-, strain-, and velocity-related diagnostics, the underlying mechanism behind blast wave amplification/mitigation and its relation with foam density and length are proposed.
Intelligently Constructing Polyaniline/Nickel Hydroxide Core–Shell Nanoflowers as Anode for Flexible Electrode-Enhanced Lithium-/Sodium-Ion Batteries
Authors: Xiao Zhiyuan , Li Xinyi , Gao Zhiyang , Qi Meili , Mu Xin , Pan Jiaqi 
Published: November 2024

Abstract
The intelligent design of advanced anode materials plays a pivotal role in energy storage for lithium-ion (LIBs) and sodium-ion batteries (SIBs), offering the potential for broadening their practical applications through the development of flexible electrodes. In this study, nickel hydroxide nanoflowers grown on Ni foam (Ni(OH)2 NFs/NF) were synthesized by hydrothermal method. Subsequently, nickel hydroxide nanoflowers–polyaniline (Ni(OH)2 NFs/PANI) were synthesized by electrodeposition method. Ni(OH)2 NFs/NF and Ni(OH)2 NFs/PANI can be straightforwardly utilized as pliable electrodes. For the first discharge capacity, Ni(OH)2 NFs/PANI electrode delivers a higher capacity (1608.1 mAh g−1) than Ni(OH)2 NFs/NF (1464.1 mAh g−1) for LIBs. For the first discharge capacity, Ni(OH)2 NFs/PANI electrode delivers a superior capacity (473.4 mAh g−1) than Ni(OH)2 NFs/NF (406.6 mAh g−1) for SIBs. Ni(OH)2 NFs/PANI electrode demonstrated enhanced rate performance and cycling stability than the Ni(OH)2 NFs/NF electrode.
The role of serum albumin in
Candida albicans
filamentation, germ tube formation, and farnesol sequestration
Authors: Gutzmann Daniel J. , Toomey Brigid M. , Atkin Audrey L. , Nickerson Kenneth W. 
Published: November 2024

ABSTRACT

Candida albicans
is an opportunistic pathogen and colonizer of the human gut and mucosal membranes.
C. albicans
exhibits morphological plasticity, which is crucial for its fitness within the host and virulence. Morphogenesis in
C. albicans
is regulated, in part, by its production of farnesol, an autoregulatory molecule that inhibits filamentation. Morphogenesis is also regulated in response to external cues, such as serum, which stimulates hyphal formation by
C. albicans
. The precise mechanism by which serum stimulates hyphal formation is unknown. The most abundant serum protein is albumin. The binding affinity of albumin for nonpolar, fatty-acid-like molecules suggests that it may interact directly with exogenous farnesol and influence morphogenesis through sequestration of free farnesol. To test this hypothesis, we assessed whether albumin and albumin devoid of fatty acids (i) stimulated farnesol secretion and (ii) influenced the farnesol threshold required to inhibit filamentation. We found that albumin promoted farnesol secretion and filamentation, and the extent of its ability to do so was based on the presence or absence of bound fatty acids. We hypothesize that albumin not bound to fatty acids has the capacity to bind to farnesol and sequester it from
C. albicans
, encouraging filamentation.

IMPORTANCE

For at least 50 years, researchers have wondered about the mechanisms by which serum stimulates germ tube formation (GTF) and hyphal growth in
C. albicans
. Here, we tested a model (Nickerson et al., Microbiol Mol Biol Rev 88:e00081-22, 2024,
https://doi.org/10.1128/mmbr.00081-22
) that serum promotes GTF and farnesol synthesis in part by extracting internal farnesol (F
i
) from the cells toward the excess binding capacity of the albumins. The data presented here suggests that albumin not bound by fatty acids sequesters free farnesol thereby modulating filamentation and farnesol secretion by altering the equilibrium of internal vs external farnesol. We expect that the influence of secreted farnesol on cell morphology will differ during pathogenesis depending on location within the body, but sequestration of farnesol in the blood could mediate immune cell recruitment and promote hyphal formation.
Identification of the critical residues of TMPRSS2 for entry and host range of human coronavirus HKU1
Authors: Chen Yahan , Ou Xiuyuan , Li Pei , Zan Fuwen , Tan Lin , Qian Zhaohui 
Published: November 2024

ABSTRACT

Human coronavirus (CoV) HKU1 infection typically causes common cold but can lead to pneumonia in children, older people, and immunosuppressed individuals. Recently, human transmembrane serine protease 2 (hTMPRSS2) was identified as the functional receptor for HKU1, but its region and residues critical for HKU1 S binding remain elusive. In this study, we find that HKU1 could utilize human and hamster, but not rat, mouse, or bat TMPRSS2 for virus entry, displaying a narrow host range. Using human–bat TMPRSS2 chimeras, we show that the serine peptidase (SP) domain of TMPRSS2 is essential for entry of HKU1. Further extensive mutagenesis analyses of the C-terminal regions of SP domains of human and bat TMPRSS2s identify residues 417 and 469 critical for entry of HKU1. Replacement of either D417 or Y469 with asparagine in hTMPRSS2 abolishes its abilities to mediate entry of HKU1 S pseudovirions and cell–cell fusion, whereas substitution of N417 with D or N469 with Y in bat TMPRSS2 (bTMPRSS2) renders it supporting HKU1 entry. Our findings contribute to a deeper understanding of coronavirus–receptor interactions and cross-species transmission.

IMPORTANCE
The interactions of coronavirus (CoV) S proteins with their cognate receptors determine the host range and cross-species transmission potential. Recently, human transmembrane serine protease 2 (hTMPRSS2) was found to be the receptor for HKU1. Here, we show that the TMPRSS2 of hamster, but not rat, mouse, or bat, can serve as a functional entry receptor for HKU1. Moreover, swapping the residues at the positions of 417 and 469 of bTMPRSS2 with the corresponding residues of hTMPRSS2 confers it supporting entry of HKU1 S pseudovirions, indicating the critical role of these residues in HKU1 entry. Our study identified the critical residues in hTMPRSS2 responsible for receptor interaction and host range of HKU1.
The complete genome sequence of “
Candidatus
Liberibacter asiaticus” strain 9PA and the characterization of field strains in the Brazilian citriculture
Authors: Dutra Michele F. S. , Silva Priscila A. , Chen Jianchi , Wulff Nelson A. 
Published: November 2024

ABSTRACT

“
Candidatus
Liberibacter asiaticus” (CLas) is associated with citrus huanglongbing, a severe disease with global importance that affects citrus production in Brazil. This study reports the first complete genome of a Brazilian strain of CLas. The genomic structure comparison of strain 9PA with those of 13 complete CLas genomes revealed 9,091 mismatches and 992 gaps/insertions, highlighting eight locally colinear blocks, among which six are in the prophage region. Phylogenetic analysis categorized 13 CLas genomes into two clusters with 9PA clustered with strains from China and the United States. Whole-genomic comparison identified diverse hypervariable genomic regions (HGRs). Three HGRs in the chromosomal region and three in the prophage region were selected and investigated by polymerase chain reaction. HGRs assessed from 68 samples, from medium- to high-huanglongbing incidence areas in Sao Paulo state, were grouped into haplotypes A to P. Haplotype A, which includes strain 9PA, is the second most prevalent, representing 19.1% of the samples. Haplotype B, the most common, accounts for 42.6%. Together with haplotype C, these make up 72% of the evaluated samples. The 9PA strain has prophage P-9PA-1, both integrated and circularized, and P-9PA-3, only found in a circularized form. Prophages show high identity with SC1 (83%) and P-JXGC-3 (98%). Co-occurrence of both type 1 and 3 prophages was observed in field samples. The approach employed provides insights into the Brazilian CLas population, providing markers for population studies and highlighting the prevalence of type 1 and 3 prophages in the population.

IMPORTANCE
CLas is a destructive pathogen responsible for causing the severe citrus disease known as huanglongbing. Our study presents the first fully sequenced Brazilian strain of CLas, designated as 9PA, and includes an analysis of two prophages occurring in this strain. The main objective of our research was to compare the genome features of this Brazilian strain with other fully sequenced genomes and to identify its hypervariable genetic regions. These regions were subsequently used to assess genomic variability within both the chromosomal and prophage regions in Brazilian isolates of CLas. Our findings offer valuable insights into the diversified adaptation of CLas.
Physiological oxygen concentration during sympathetic primary neuron culture improves neuronal health and reduces HSV-1 reactivation
Authors: Dochnal Sara A. , Krakowiak Patryk A. , Whitford Abigail L. , Cliffe Anna R. 
Published: November 2024

ABSTRACT

Herpes simplex virus-1 (HSV-1) establishes a latent infection in peripheral neurons and periodically reactivates in response to a stimulus to permit transmission.
In vitro
models using primary neurons are invaluable to studying latent infection because they use bona fide neurons that have undergone differentiation and maturation
in vivo
. However, culture conditions
in vitro
should remain as close to those
in vivo
as possible. This is especially important when considering minimizing cell stress, as it is a well-known trigger of HSV reactivation. We recently developed an HSV-1 model system that requires neurons to be cultured for extended lengths of time. Therefore, we sought to refine culture conditions to optimize neuronal health and minimize secondary effects on latency and reactivation. Here, we demonstrate that culturing primary neurons under conditions closer to physiological oxygen concentrations (5% oxygen) results in cultures with features consistent with reduced stress. Furthermore, culture in these lower oxygen conditions diminishes the progression to full HSV-1 reactivation despite minimal impacts on latency establishment and earlier stages of HSV-1 reactivation. We anticipate that our findings will be useful for the broader microbiology community as they highlight the importance of considering physiological oxygen concentration in studying host-pathogen interactions.

IMPORTANCE

Establishing models to investigate host-pathogen interactions requires mimicking physiological conditions as closely as possible. One consideration is the oxygen concentration used for
in vitro
tissue culture experiments. Standard incubators do not regulate oxygen levels, exposing cells to oxygen concentrations of approximately 18%. However, cells within the body are exposed to much lower oxygen concentrations, with physiological oxygen concentrations in the brain being 0.55%–8% oxygen. Here, we describe a model for herpes simplex virus 1 (HSV-1) latent infection using neurons cultured in 5% oxygen. We show that culturing neurons in more physiological oxygen concentrations improves neuronal health to permit long-term studies of virus-cell interactions and the impact on reactivation.
Binary Coded Unary Regular Languages
Authors: Geffert Viliam , Pališínová Dominika , Šebej Juraj 
Published: November 2024

[Formula: see text] is a binary coded unary regular language, if there exists a unary regular language [Formula: see text] such that [Formula: see text] is in [Formula: see text] if and only if the binary representation of [Formula: see text] is in [Formula: see text]. If a unary language [Formula: see text] is accepted by a minimal deterministic finite automaton (DFA) [Formula: see text] with [Formula: see text] states, then its binary coded version [Formula: see text] is regular and can be accepted by a DFA [Formula: see text] using at most [Formula: see text] states, but at least [Formula: see text] states. There are witness languages matching these upper and lower bounds exactly, for each [Formula: see text]. More precisely, if [Formula: see text] uses [Formula: see text] states in the initial segment and [Formula: see text] states in the loop, where [Formula: see text] is odd and [Formula: see text], then the minimal [Formula: see text] for [Formula: see text] consists of a preamble with at most [Formula: see text] but at least [Formula: see text] states, except for [Formula: see text] with no preamble, and a kernel with at most [Formula: see text] but at least [Formula: see text] states. Also these lower bounds are matched exactly by witness languages, for each [Formula: see text]. If the length of the loop is fixed, the size of the preamble is bounded by [Formula: see text]. The conversion in the opposite way is not always granted: there are binary regular languages the unary versions of which are not even context free. The conversion of a unary nondeterministic finite automaton (NFA) to a binary NFA uses [Formula: see text] states and introduces a binary version of Chrobak normal form.
Blood Pressure Regulation in Post–COVID POTS: Beyond Sinus Tachycardia
Authors: Johansson Madeleine , Ståhlberg Marcus , Ricci Fabrizio , Lewinter Christian , Hamrefors Viktor , Nilsson Peter M. , Sutton Richard , Fedorowski Artur 
Published: November 2024

BACKGROUND:
Postural orthostatic tachycardia syndrome (POTS) is a frequently diagnosed cardiovascular disorder after COVID-19 infection. POTS is characterized by the presence of excessive sinus tachycardia on standing without a fall in blood pressure (BP). We investigated the BP profile using 24-hour ambulatory BP monitoring in patients with new-onset POTS after COVID-19 compared with prepandemic population-based controls.

METHODS:
We performed a case-control study in 100 patients (mean age, 40.0±12.9 years; 85% women) with verified post–COVID-19 new-onset POTS diagnosed by a positive head-up tilt testing versus 100 controls from a population-based cohort with a negative active standing test, no history of syncope, POTS, or endocrine disease (mean age, 42.3±14.0 years; 78% women). Twenty-four-hour BP profile was assessed for circadian BP variation including hypotensive systolic BP (SBP) episodes (<80, <90, and <100 mm Hg).

RESULTS:

Patients with post–COVID-19 POTS had significantly higher nighttime SBP, but not daytime SBP, and more daytime SBP hypotensive episodes compared with controls. Nondipping (34% versus 19%;
P
<0.001) and reverse dipping patterns (9% versus 0%;
P
<0.001) were more frequent in post–COVID-19 POTS. In the logistic regression, patients with post–COVID-19 POTS had significantly higher mean 24-hour SBP (odds ratio, 1.08 [95% CI, 1.04–1.11];
P
<0.001) and nighttime SBP (odds ratio, 1.07 [95% CI, 1.04–1.10];
P
<0.001), independent of age and sex.

CONCLUSIONS:
Patients with post–COVID-19 POTS demonstrate higher mean 24-hour and nighttime SBP and show disruptions of circadian BP rhythm regulation compared with population-based controls, as well as more daytime hypotensive episodes. Future studies are needed to test whether patients with post–COVID-19 POTS may benefit from tailored BP therapy.