bluuebunny/crossref_metadata_2025_split huggingface dataset:
Operational Modal Analysis and Baseline-Free Damage Detection of a Beam Under Random Excitation via a Novel Demodulation Method With a Reference Signal
Authors: Lyu Linfeng , Yuan Ke , Zhu Weidong 
Published: February 2024

Abstract
A novel demodulation method with a reference signal is developed for operational model analysis of a beam structure under a random excitation. The novel demodulation method can process measurements of the beam by a continuously scanning laser Doppler vibrometer (CSLDV) system and measurements of a reference point on the beam by a single-point laser Doppler vibrometer to estimate its modal parameters, such as damped natural frequencies and undamped mode shapes. Damped natural frequencies of the beam are estimated from fast Fourier transforms of measurements of the CSLDV system. A cross-correlation function between a measurement of the CSLDV system and a measurement of a single-point laser Doppler vibrometer is calculated, and the cross-correlation function is multiplied by a sinusoidal signal whose frequency is one estimated damped natural frequency of the beam. The processed cross-correlation function is filtered by a low-pass filter to obtain the undamped mode shape of the beam that corresponds to the damped natural frequency of the beam. Smooth polynomials are used to fit estimated undamped mode shapes, which can be considered as undamped mode shapes of an undamaged beam. Curvatures of estimated undamped mode shapes and polynomials are compared by curvature damage indices to determine the location of a damage in the beam. The novel demodulation method is investigated by measurements from both finite element simulation and experiment. Modal parameters of a finite element damaged beam model and a damaged beam specimen, which are under random excitation, are successfully estimated, and locations of damages in the beam model and beam specimen are accurately determined. The novel demodulation method with a reference signal can be used for damage detection of a beam structure under random excitation, while a traditional demodulation method can be only used for damage detection of a beam structure under sinusoidal excitation.
On the Prediction of Fuel Consumption for Dual-Fuel Low-Speed Marine Engines
Authors: Rempel da Silva Amanda , França Gean Carlos , Ordonez Juan Carlos , Hood Marques Crístofer 
Published: February 2024

Abstract
The International Maritime Organization has been concerned with the pollution from ships and has enforced regulations to reduce greenhouse gas emissions. In this context, specific fuel consumption is a crucial parameter to select the most efficient and environmentally friendly engine. This parameter can be obtained by means of simulation models with various levels of sophistication, which can be either coded in basic programming languages or run in dedicated packages. The aim of the present study is to conceive a simplified model to predict the specific fuel consumption of low-speed dual-fuel engines with low-pressure gas injection driving either fixed or controllable pitch propellers. Clear specific fuel consumption trends were revealed when a normalization process was employed and then polynomials were obtained by numerical regression. This model requires very limited input data to predict the specific fuel consumption of an engine at any contractual maximum continuous rating, including part load operation. Results showed very close qualitative behavior and the highest deviations occurred for the brake-specific pilot consumption, peaking at about 5%. At last, the developed approach was concluded to be an easy-to-implement and fast-to-run model with promising usage for optimization studies.
Investigation of Nanofin Effect (nFE) for Investigating the Anomalous Properties of Nanofluids
Authors: Bhattacharya Ritwik , Shettigar Nandan , Thyagarajan Ashok , Shafiee Shahin , Banerjee Debjyoti 
Published: February 2024

Abstract
In this study, oleo-nanofluids containing casein (protein nanoparticles) in paraffin oil (which is also a phase change material) were synthesized and the density of the extracted nanofluids was measured using the Archimedean principle of buoyancy. Control experiments were performed to ascertain the long-term stability of the colloidal suspensions by introducing minute variations in the synthesis protocol. The experimental results show an overall enhancement of 13.79% in density compared to the neat solvent. Furthermore, the colloidal density deviates by 6.45% from the values predicted by the conventional mixture rule. This unusual phenomenon of “deviant” or surplus density can be attributed to the formation of a semi-crystalline compressed phase in the non-aqueous fluid domain. The experimental data reported in the present study will be used in the design of experiments for investigating the influence of the “nanofin effect” (nFE) upon the density deviation observed in oleo-nanofluids.
Simulation and Modeling for the Vaporization of a Freely Moving Drop at Moderate Weber Numbers
Authors: Boyd Bradley , Becker Sid , Ling Yue 
Published: February 2024

Abstract
The vaporization of a freely moving liquid droplet in a uniform high-temperature gas stream is investigated through direct numerical simulation. The sharp liquid-gas interface is tracked using the geometric Volume-of-Fluid (VOF) method. The incompressible Navier-Stokes equations are solved in conjunction with a two-fluid model for thermal energy advection and conduction, with an immersed Dirichlet boundary condition at the interface to implicitly account for latent heat absorption. The model is implemented in the open-source solver Basilisk, which uses adaptive quadtree/octree mesh for spatial discretization and allows for adaptive mesh refinement of the region near the interface. Simulations of an acetone droplet at moderate Weber numbers are conducted, where the droplet morphology evolution varies from vibrational to bag breakup modes. We observe an increase in the vaporization rate of the droplet as it deforms, and a strong correlation between the windward surface area of the droplet and the vaporization rate is found.
Evolutionary history influences the microbiomes of a female symbiotic reproductive organ in cephalopods
Authors: Vijayan Nidhi , McAnulty Sarah J. , Sanchez Gustavo , Jolly Jeffrey , Ikeda Yuzuru , Nishiguchi Michele K. , Réveillac Elodie , Gestal Camino , Spady Blake L. , Li Diana H. , Burford Benjamin P. , Kerwin Allison H. , Nyholm Spencer V. 
Published: February 2024

ABSTRACT

Many female squids and cuttlefishes have a symbiotic reproductive organ called the accessory nidamental gland (ANG) that hosts a bacterial consortium involved with egg defense against pathogens and fouling organisms. While the ANG is found in multiple cephalopod families, little is known about the global microbial diversity of these ANG bacterial symbionts. We used 16S rRNA gene community analysis to characterize the ANG microbiome from different cephalopod species and assess the relationship between host and symbiont phylogenies. The ANG microbiome of 11 species of cephalopods from four families (superorder: Decapodiformes) that span seven geographic locations was characterized. Bacteria of class
Alphaproteobacteria, Gammaproteobacteria
, and
Flavobacteriia
were found in all species, yet analysis of amplicon sequence variants by multiple distance metrics revealed a significant difference between ANG microbiomes of cephalopod families (weighted/unweighted UniFrac, Bray–Curtis,
P
= 0.001). Despite being collected from widely disparate geographic locations, members of the family Sepiolidae (bobtail squid) shared many bacterial taxa including (~50%)
Opitutae
(Verrucomicrobia) and
Ruegeria
(Alphaproteobacteria) species. Furthermore, we tested for phylosymbiosis and found a positive correlation between host phylogenetic distance and bacterial community dissimilarity (Mantel test
r
= 0.7). These data suggest that closely related sepiolids select for distinct symbionts from similar bacterial taxa. Overall, the ANGs of different cephalopod species harbor distinct microbiomes and thus offer a diverse symbiont community to explore antimicrobial activity and other functional roles in host fitness.

IMPORTANCE
Many aquatic organisms recruit microbial symbionts from the environment that provide a variety of functions, including defense from pathogens. Some female cephalopods (squids, bobtail squids, and cuttlefish) have a reproductive organ called the accessory nidamental gland (ANG) that contains a bacterial consortium that protects eggs from pathogens. Despite the wide distribution of these cephalopods, whether they share similar microbiomes is unknown. Here, we studied the microbial diversity of the ANG in 11 species of cephalopods distributed over a broad geographic range and representing 15–120 million years of host divergence. The ANG microbiomes shared some bacterial taxa, but each cephalopod species had unique symbiotic members. Additionally, analysis of host–symbiont phylogenies suggests that the evolutionary histories of the partners have been important in shaping the ANG microbiome. This study advances our knowledge of cephalopod–bacteria relationships and provides a foundation to explore defensive symbionts in other systems.
Class A capsid assembly modulator apoptotic elimination of hepatocytes with high HBV core antigen level
in vivo
is dependent on
de novo
core protein translation
Authors: Berke Jan Martin , Tan Ying , Sauviller Sarah , Wu Dai-tze , Zhang Ke , Conceição-Neto Nádia , Blázquez Moreno Alfonso , Kong Desheng , Kukolj George , Li Chris , Zhu Ren , Nájera Isabel , Pauwels Frederik 
Published: February 2024

ABSTRACT

Capsid assembly is critical in the hepatitis B virus (HBV) life cycle, mediated by the viral core protein. Capsid assembly is the target for new anti-viral therapeutics known as capsid assembly modulators (CAMs) of which the CAM-aberrant (CAM-A) class induces aberrant shaped core protein structures and leads to hepatocyte cell death. This study aimed to identify the mechanism of action of CAM-A modulators leading to HBV-infected hepatocyte elimination where CAM-A-mediated hepatitis B surface antigen (HBsAg) reduction was evaluated in a stable HBV replicating cell line and in AAV-HBV-transduced C57BL/6, C57BL/6 SCID, and HBV-infected chimeric mice with humanized livers. Results showed that
in vivo
treatment with CAM-A modulators induced pronounced reductions in hepatitis B e antigen (HBeAg) and HBsAg, associated with a transient alanine amino transferase (ALT) increase. Both HBsAg and HBeAg reductions and ALT increase were delayed in C57BL/6 SCID and chimeric mice, suggesting that adaptive immune responses may indirectly contribute. However, CD8+ T cell depletion in transduced wild-type mice did not impact antigen reduction, indicating that CD8+ T cell responses are not essential. Transient ALT elevation in AAV-HBV-transduced mice coincided with a transient increase in endoplasmic reticulum stress and apoptosis markers, followed by detection of a proliferation marker. Microarray data revealed antigen presentation pathway (major histocompatibility complex class I molecules) upregulation, overlapping with the apoptosis. Combination treatment with HBV-specific siRNA demonstrated that CAM-A-mediated HBsAg reduction is dependent on
de novo
core protein translation. To conclude, CAM-A treatment eradicates HBV-infected hepatocytes with high core protein levels through the induction of apoptosis, which can be a promising approach as part of a regimen to achieve functional cure.

IMPORTANCE

Treatment with hepatitis B virus (HBV) capsid assembly modulators that induce the formation of aberrant HBV core protein structures (CAM-A) leads to programmed cell death, apoptosis, of HBV-infected hepatocytes and subsequent reduction of HBV antigens, which differentiates CAM-A from other CAMs. The effect is dependent on the
de novo
synthesis and high levels of core protein.
African swine fever virus A137R assembles into a dodecahedron cage
Authors: Li Changyao , Jia Mingzhu , Hao Tianjiao , Peng Qi , Peng Ruchao , Chai Yan , Shi Yi , Song Hao , Gao George F. 
Published: February 2024

ABSTRACT

African swine fever (ASF) is a highly contagious viral disease that affects domestic and wild pigs. The causative agent of ASF is African swine fever virus (ASFV), a large double-stranded DNA virus with a complex virion structure. Among the various proteins encoded by ASFV, A137R is a crucial structural protein associated with its virulence. However, the structure and molecular mechanisms underlying the functions of A137R remain largely unknown. In this study, we present the structure of A137R determined by cryogenic electron microscopy single-particle reconstruction, which reveals that A137R self-oligomerizes to form a dodecahedron-shaped cage composed of 60 polymers. The dodecahedron is literally equivalent to a
T =
1 icosahedron where the icosahedral vertexes are located in the center of each dodecahedral facet. Within each facet, five A137R protomers are arranged in a head-to-tail orientation with a long N-terminal helix forming the edge through which adjacent facets stitch together to form the dodecahedral cage. Combining structural analysis and biochemical evidence, we demonstrate that the N-terminal domain of A137R is crucial and sufficient for mediating the assembly of the dodecahedron. These findings imply the role of A137R cage as a core component in the icosahedral ASFV virion and suggest a promising molecular scaffold for nanotechnology applications.

IMPORTANCE
African swine fever (ASF) is a lethal viral disease of pigs caused by African swine fever virus (ASFV). No commercial vaccines and antiviral treatments are available for the prevention and control of the disease. A137R is a structural protein of ASFV that is associated with its virulence. The discovery of the dodecahedron-shaped cage structure of A137R in this study is of great importance in understanding ASFV pathogenicity. This finding sheds light on the molecular mechanisms underlying the functions of A137R. Furthermore, the dodecahedral cage formed by A137R shows promise as a molecular scaffold for nanoparticle vectors. Overall, this study provides valuable insights into the structure and function of A137R, contributing to our understanding of ASFV and potentially opening up new avenues for the development of vaccines or treatments for ASF.
Complete genome sequence of the
Microbacterium foliorum
bacteriophage Garey24
Authors: Migueletti Matías R. , García Rey Julieta , Micheloni Josefina , Lomanto Camila , Martelli Elisa , Sánchez Gastón , Colombo Julián M. , Vallecillo Luciano M. , Lamagni Francisco , Giusti Tomás , Acosta Fabrina , Villagrán Franco , Gvozdenovich Martín , Pricco Frakich Abril , Pianesi Tulio , Tulin Gonzalo , Mascali Florencia C. , Petitti Tomás D. , Torres Manno Mariano A. , Fusari Corina M. , Buttigliero Laura , Giordana María Florencia , Gramajo Hugo , Diacovich Lautaro , Espariz Martín , Mussi María Alejandra 
Published: February 2024

ABSTRACT

In this work, we report the discovery and characterization of Garey24, a bacteriophage that forms medium-size plaques with halo rings isolated from a soil sample in Funes, Argentina. Its 41,522 bp circularly permuted genome contains 63 putative protein-coding genes. Based on gene content similarity, Garey24 was assigned to subcluster EA1.
In vitro
lung epithelial cell model reveals novel roles for
Pseudomonas aeruginosa
siderophores
Authors: Kang Donghoon , Xu Qi , Kirienko Natalia V. 
Published: February 2024

ABSTRACT

The multidrug-resistant pathogen
Pseudomonas aeruginosa
is a common nosocomial respiratory pathogen that continues to threaten the lives of patients with mechanical ventilation in intensive care units and those with underlying comorbidities such as cystic fibrosis or chronic obstructive pulmonary disease. For over 20 years, studies have repeatedly demonstrated that the major siderophore pyoverdine is an important virulence factor for
P. aeruginosa
in invertebrate and mammalian hosts
in vivo
. Despite its physiological significance, an
in vitro
, mammalian cell culture model that can be used to characterize the impact and molecular mechanisms of pyoverdine-mediated virulence has only been developed very recently. In this study, we adapt a previously-established, murine macrophage-based model to use human bronchial epithelial (16HBE) cells. We demonstrate that conditioned medium from
P. aeruginosa
induced rapid 16HBE cell death through the pyoverdine-dependent secretion of cytotoxic rhamnolipids. Genetic or chemical disruption of pyoverdine biosynthesis decreased rhamnolipid production and mitigated cell death. Consistent with these observations, chemical depletion of lipids or genetic disruption of rhamnolipid biosynthesis abrogated the toxicity of the conditioned medium. Furthermore, we also examine the effects of exposure to purified pyoverdine on 16HBE cells. While pyoverdine accumulated within cells, it was largely sequestered within early endosomes, resulting in minimal cytotoxicity. More membrane-permeable iron chelators, such as the siderophore pyochelin, decreased epithelial cell viability and upregulated several pro-inflammatory genes. However, pyoverdine potentiated these iron chelators in activating pro-inflammatory pathways. Altogether, these findings suggest that the siderophores pyoverdine and pyochelin play distinct roles in virulence during acute
P. aeruginosa
lung infection.

IMPORTANCE

Multidrug-resistant
Pseudomonas aeruginosa
is a versatile bacterium that frequently causes lung infections. This pathogen is life-threatening to mechanically-ventilated patients in intensive care units and is a debilitating burden for individuals with cystic fibrosis. However, the role of
P. aeruginosa
virulence factors and their regulation during infection are not fully understood. Previous murine lung infection studies have demonstrated that the production of siderophores (e.g., pyoverdine and pyochelin) is necessary for full
P. aeruginosa
virulence. In this report, we provide further mechanistic insight into this phenomenon. We characterize distinct and novel ways these siderophores contribute to virulence using an
in vitro
human lung epithelial cell culture model.
All-cause mortality risks among participants in mass-participation sporting events
Authors: Bakker Esmée A , Aengevaeren Vincent L. , Lee Duck-Chul , Thompson Paul D , Eijsvogels Thijs M.H. 
Published: February 2024

ObjectivesExercise transiently increases the risk for sudden death, whereas long-term exercise promotes longevity. This study assessed acute and intermediate-term mortality risks of participants in mass-participation sporting events.MethodsData of participants in Dutch running, cycling and walking events were collected between 1995 and 2017. Survival status was obtained from the Dutch Population Register. A time-stratified, case-crossover design examined if deceased participants more frequently participated in mass-participation sporting events 0–7 days before death compared with the reference period (14–21 days before death). Mortality risks during follow-up were compared between participants and non-participants from the general population using Cox regression.Results546 876 participants (median (IQR) age 41 (31–50) years, 56% male, 72% runners) and 211 592 non-participants (41 (31–50) years, 67% male) were included. In total, 4625 participants died of which more participants had partaken in a sporting event 0–7 days before death (n=23) compared with the reference period (n=12), and the mortality risk associated with acute exercise was greater but did not reach statistical significance (OR 1.92; 95% CI 0.95 to 3.85). During 3.3 (1.1–7.4) years of follow-up, participants had a 30% lower risk of death (HR 0.70; 95% CI 0.67 to 0.74) compared with non-participants after adjustment for age and sex. Runners (HR 0.65; 95% CI 0.62 to 0.69) and cyclists (HR 0.70; 95% CI 0.64 to 0.77) had the best survival during follow-up followed by walkers (HR 0.88; 95% CI 0.80 to 0.94).ConclusionParticipating in mass-participation sporting events was associated with a non-significant increased odds (1.92) of mortality and a low absolute event rate (4.2/100 000 participants) within 7 days post-event, whereas a 30% lower risk of death was observed compared with non-participants during 3.3 years of follow-up. These results suggest that the health benefits of mass sporting event participation outweigh potential risks.
‘They treat us like machines’: migrant workers’ conceptual framework of labour exploitation for health research and policy
Authors: Boufkhed Sabah , Thorogood Nicki , Ariti Cono , Durand Mary Alison 
Published: February 2024

BackgroundThe exploitation of migrant workers ranks high on global political agendas including the Sustainable Development Goals. Research on exploited workers, using assessment tools where exploitation is defined by professional experts, indicates serious health concerns and needs. Yet, migrant workers are rarely asked about their understanding of a phenomenon they may experience. Our study aimed to conceptualise ‘labour exploitation’ from the perspective of migrant workers employed in manual low-skilled jobs.MethodsTwenty-seven Latin Americans working in London (UK) participated in Group Concept Mapping; a participatory mixed-method where qualitative data are collected to define a concept’s content and then analysed using quantitative methods to generate a structured conceptual framework. Participants generated statements describing the concept content during brainstorming sessions, and structured them during sorting-rating exercises. Multi-Dimensional Scaling and Cluster Analysis were performed, generating a conceptual framework that clarified the dimensions, subdimensions and constituent statements of the concept of labour exploitation from migrant workers’ perspectives.ResultsThree key dimensions were identified: ‘poor employment conditions and lack of protection’, covering contractual arrangements and employment relations; ‘disposability and abuse of power’ (or ‘dehumanisation’) covering mechanisms or means which make migrant workers feel disposable and abused; and ‘health and safety and psychosocial hazards’ encompassing issues from physical and psychosocial hazards to a lack of health and social protection. ‘Dehumanisation’ has not been included in mainstream tools assessing exploitation, despite its importance for study participants who also described harsh situations at work including sexual, physical and verbal abuse.ConclusionOur study provides a conceptual framework of labour exploitation that gives voice to migrant workers and can be operationalised into a measure of migrant labour exploitation. It also calls for the dimension ‘dehumanisation’ and structural forms of coercion to be integrated into mainstream conceptualisations, and their workplace hazards to be urgently addressed.