bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influences of Sediment Particles on Air Vessel Water Hammer Protection Effect in the Long-Distance Water Supply Systems
Authors: Wang Yiran , Yu Xiaodong , Liu Jiachun , Shi Lin , Zhang Jian 
Published: October 2023

Abstract
Long-distance water supply systems are important measures to improve the water resources distribution, and the water hammer protection devices such as air vessels are usually added in the project to ensure the safety and stable operation. However, the sediment particles are always ignored in the design. Hence, a numerical model and program were established for sediment laden water hammer based on the method of characteristics (MOC). Using the proposed model, the water hammer protection influences of sediment particles parameters are simulated for the same pipeline system of a water supply project. The result shows that the resistance loss of sediment-laden water in pipelines is larger than that of water, and the initial head of pump needed to be increased to ensure the water levels of downstream reservoirs are consistent. After power failure and pump stopping, the negative pressure wave of sediment-laden water is 2.97 m higher than that of water, and the theoretical minimum internal pressure along pipelines is 7.8 m lower. With the same air vessel protection, the lowest minimum internal pressure heads along pipelines decrease with the increase of quantities of sediment, while the results show no obvious influence by changes of median particle diameters. The lowest absolute pressure of pipeline could reach −0.69 m under the condition of 50 kg/m3 quantity of sediment and 0.05 mm median particle diameter. The relevant research results are of great significance sediment-laden water hammer numerical simulation and water hammer protection design.
Improving Weldability of Press Hardened Steel Through Combining Stepped Current Pulse and Magnetically Assisted Resistance Spot Welding Process
Authors: Li ZhuoRan , Zhang DianPing , Chen RuiMing , Wang SongLin , Xia YuJun , Lou Ming , Li YongBing 
Published: October 2023

Abstract
Press-hardened steel (PHS), characterized by its extremely high strength, has wide applications in vehicle body manufacturing as an innovative lightweight material. Nevertheless, the poor weldability of PHS results in poor weld toughness and a high risk of interfacial fracture (IF), posing challenges to the resistance spot welding (RSW) process. Introducing an external magnetic field in the welding process to perform electromagnetic stirring (EMS), the magnetically assisted RSW (MA-RSW) process has been proven an effective method to improve the weld toughness of high-strength steel, but it may increase the risk of expulsion. In response to these challenges, this study introduces a new process called SPMA-RSW to improve the weldability of PHS by combining MA-RSW and the stepped-current pulses (SP) technique, which can enlarge the weld lobe. Nugget appearance, microstructure, microhardness, and mechanical properties were systematically investigated by comparing traditional RSW, MA-RSW, SP-RSW, and SPMA-RSW. The result showed that the SPMA-RSW process would significantly increase the nugget size, inhibit the shrinkage voids, finer the grain size of PHS welds, and harden the nugget region. This increased the lap-shear strength and changed the fracture mode from brittle IF mode to ductile plug fracture (PF) mode at the same heat input. Specifically, the peak load and energy absorption were increased by 32.3% and 84.2%, respectively. Then, an analytical model was developed to reveal the mechanism of the effect of EMS on the fracture mode transition and was verified by experiment. This work can help improve the weld quality and thermal efficiency of the RSW process for PHS.
Exploring Physics of Acoustic Flow Control Over Airfoils Toward Potential Application to High Work and Lift Turbines
Authors: Celik Acar , Mitra Abhijit , Agarwal Tapish , Clark John , Jacobi Ian , Cukurel Beni 
Published: October 2023

Abstract
In this study, acoustic actuation was applied experimentally to massively separated flows on simplified hump geometries, which mimic the pressure distribution over high-work-and-lift low Reynolds airfoils. The acoustic excitation demonstrated significant control over flow separation, resulting in higher relative lift enhancement than standard, localized actuation techniques with similar momentum coefficients. Full-field velocity measurements were used to examine the transient behavior of the actuated flow in order to explain the physical mechanism of separation control. The velocity measurements revealed the presence of a viscous wall mode that organized the vorticity upstream of the separation point. A spatio-temporal correlation analysis found that the generation of these wall modes in the attached flow was the dominant cause of the subsequent reorganization of the separating shear layer and the change in separation dynamics. The importance of wall modes to acoustic flow control mechanism has important implications for the design of new acoustic control strategies for high-speed turbomachinery. Along these lines, the ramifications of this phenomena are explored over geometries, which are designed to approximate flow fields in high-speed turbomachinery. At the conducive Strouhal number, which scale linearly with the square root of Reynolds numbers, up to 22% lift enhancement is observed for excitation amplitudes in the range of ∼128 dB, typical to the engine environment. Of the many diverse flow control techniques, acoustics can be effectively employed in low Reynolds turbine blades, which are prone to flow separation in the off-design conditions with the ever increasing demand for higher flow turning.
Impacts of Injection Parameters on the Mixture Formation and Performance of Two-Stroke Spark-Ignition Direct-Injection Aviation Kerosene Engine
Authors: Wang Ying , Zhou Qiongyang 
Published: October 2023

Abstract
Two-stroke spark-ignition engines play a significant role in the field of power sources of small and medium unmanned aerial vehicles. There is a certain transition from burning gasoline to aviation kerosene (or heavy oil) and from carburetor or inlet injection system to direct-injection fuel system. However, the performance of two-stroke spark-ignition direct-injection engines fueled with aviation kerosene was not very ideal under heavy loads. Generally, the mixture formation is very important for engine combustion and performance, while injection parameters have great effects on mixture formation. Thus, various injection parameters of a two-stroke direct-injection kerosene engine were examined here. The results showed too early or too late injection timing (tinj) would deteriorate the mixture formation, resulting in lower brake power and brake thermal efficiency. Here the most suitable tinj was 150 deg CA BTDC. Too high or too low injection pressure (pinj) caused fuel short circuit loss and poor mixture quality, so the optimum pinj was 10 MPa. Too large injector installation angle (β) easily results in fuel spray impingement, and too small β causes fuel short circuit loss. Therefore, the best β was concluded to be 30 deg in this paper.
Multi-Objective Numerical Optimization of Radial Turbines
Authors: Fuhrer Christopher , Kovachev Nikola , Vogt Damian M. , Raja Mahalingam Ganesh , Mann Stuart 
Published: October 2023

Abstract
The growing demand of high flexibility and wide operating ranges of radial turbines in turbocharger applications necessitates new methods in the turbomachinery design process. Often, design criteria such as high performance at certain operating conditions or low inertia contradict the requirement for high durability. This article demonstrates a newly developed optimization approach for radial turbines that allows to optimize for several design objectives. The presented approach is based on a parametric model of the turbine wheel geometry. On the one hand, the model is designed to capture the most important geometry and design features, and on the other hand, it is flexible for use on various machines. A surrogate model-based genetic algorithm is used to optimize the geometries with respect to several objectives, including efficiency, durability (HCF), low-cycle fatigue (LCF), inertia, and mass. Certain operating points or criteria can be particularly emphasized and specified constraints throughout the process allow for customized optimization. The simulations underlying the optimization are state-of-the-art computational fluid dynamics (CFD) and finite element (FE) analyses, involving the respective components. The newly developed and fully automated approach includes tasks of different disciplines. In the end, a selection of several promising geometries is examined more intimately to finally find a most suitable geometry for the given application. For the current study, this geometry has been manufactured and tested on a hot gas test facility to successfully validate the design process.
Safety of early oral ambulatory treatment of adult patients with bloodstream infections discharged from the emergency department
Authors: Casado Ana , Gimeno Adelina , Aguilar-Guisado Manuela , García Manuel , Rodríguez Jesús Francisco , Rivas Pedro Antonio , Bueno Claudio , Lepe Jose Antonio , Cisneros José Miguel , Molina José 
Published: October 2023

ABSTRACT
This study evaluates the safety of early oral ambulatory treatment of adult patients diagnosed with bacteremia after their discharge from the emergency department. A cohort of 206 febrile ambulatory patients was assessed. Bacteremic low-risk patients were recommended an oral treatment and were compared with matched febrile non-bacteremic outpatients. Rates of 14-day mortality and unplanned re-consultations were similar and below 5% in both cohorts, highlighting the safety of oral therapy of low-risk bacteremia, even from its onset.
Development of a dual fluorescent reporter system to identify inhibitors of
Staphylococcus aureus
virulence factors
Authors: Tao Zhanhua , Ke Ke , Shi Deqiang , Zhu Libo 
Published: October 2023

ABSTRACT

Staphylococcus aureus
is a leading cause of bacterial infections due to its resistance to most antibiotics and the production of diverse virulence factors. Various alternative approaches to treating staphylococcal infections have been proposed, including targeting the virulence factors or mechanisms that regulate their synthesis. The accessory gene regulator (
agr
) and the
S. aureus
exoprotein expression (
sae
) are two major virulence regulators of
S. aureus
. Here, we describe a dual reporter system capable of simultaneously monitoring the transcriptional activities of
agr
and
sae
in
S. aureus
. The reporter plasmid contained two fluorescent protein cassettes arranged back-to-back, with the mCherry cassette driven by the
agr
P3 promoter and the GFP cassette driven by the
sbi
promoter. We examined the fluorescent responses of wild-type,
agr
, and
sae
mutant strains using fluorescence microscopy and found that the activities of
agr
and
sae
systems could be detected without significant crosstalk in the dual reporter strain. The dual reporter system could be used to monitor the dynamic changes in
agr
and
sae
activities during batch growth in
S. aureus
. Additionally, we evaluated the responsiveness of the reporter strain to virulence inhibitors by treating it with several known inhibitors, including autoinducing peptides (AIPs) containing culture supernatants, indole, and flavone. The results suggested that the dual reporter system was sensitive to both
agr
and
sae
inhibitors. This reporter construct enables the characterization of the activity of a substance against two different targets in one screening round, significantly reducing screening time and expense.

IMPORTANCE

Staphylococcus aureus
is a formidable pathogen responsible for a wide range of infections, and the emergence of antibiotic-resistant strains has posed significant challenges in treating these infections. In this study, we have established a novel dual reporter system capable of concurrently monitoring the activities of two critical virulence regulators in
S. aureus
. By incorporating both reporters into a single screening platform, we provide a time- and cost-efficient approach for assessing the activity of compounds against two distinct targets in a single screening round. This innovative dual reporter system presents a promising strategy for the identification of molecules capable of modulating virulence gene expression in
S. aureus
, potentially expediting the development of antivirulence therapies.
Preclinical screen for protection efficacy of chlamydial antigens that are immunogenic in humans
Authors: Lu Chunxue , Wang Jie , Zhong Guangming 
Published: October 2023

ABSTRACT

To search for subunit vaccine candidates, immunogenic chlamydial antigens identified in humans were evaluated for protection against both infection and pathology in a mouse genital tract infection model under three different immunization regimens. The intramuscular immunization regimen was first used to evaluate 106 chlamydial antigens, which revealed that two antigens significantly reduced while 11 increased genital chlamydial burden. The two infection-reducing antigens failed to prevent pathology and 23 additional antigens even exacerbated pathology. Thus, intranasal mucosal immunization was tested next since intranasal inoculation with live
Chlamydia muridarum
prevented both genital infection and pathology. Two of the 29 chlamydial antigens evaluated were found to prevent genital infection but not pathology and three exacerbate pathology. To further improve protection efficacy, a combinational regimen (intranasal priming + intramuscular boosting + a third intraperitoneal/subcutaneous boost) was tested. This regimen identified four infection-reducing antigens, but only one of them prevented pathology. Unfortunately, this protective antigen was not advanced further due to its amino acid sequence homology with several human molecules. Two pathology-exacerbating antigens were also found. Nevertheless, intranasal mucosal priming with viable
C. muridarum
in control groups consistently prevented both genital infection and pathology regardless of the subsequent boosters. Thus, screening 140 different chlamydial antigens with 21 repeated multiple times in 17 experiments failed to identify a subunit vaccine candidate but demonstrated the superiority of viable chlamydial organisms in inducing immunity against both genital infection and pathology, laying the foundation for developing a live-attenuated Chlamydia vaccine.
Complex norovirus transmission dynamics at hospital wards revealed by deep sequencing
Authors: Widström Julia , Andersson Maria E. , Westin Johan , Wahllöf Martina , Lindh Magnus , Rydell Gustaf E. 
Published: October 2023

ABSTRACT
Detailed knowledge regarding norovirus transmission within hospitals is limited. We investigated a norovirus hospital outbreak affecting 65 patients at five different wards. PCR showed that 61 (94%) of the patients were infected with genotype II.4 strains. Successful Ion Torrent deep sequencing of GII.4 positive samples from 59 patients followed by phylogenetic analysis revealed that all sequences but two clustered into four distinct clades. Two of the clades belonged to GII.4 Sydney 2012, while the other two belonged to GII.4 New Orleans 2009. One of the clades was predominant at two wards, while two clades were predominant at one ward each. The fourth clade was found in sporadic cases at several wards. Thus, at four out of five wards, variants from one clade were predominant. At one ward, a single clade accounted for all cases, while at three wards the predominant clade accounted for 60%–71% of cases. Analysis of quasispecies variation identified positions that could further discriminate between variants from separate wards. The results illustrate a complex transmission of healthcare-associated norovirus infections and show that sequencing can be used to discriminate between related and unrelated cases.
Valid and accepted novel bacterial taxa derived from human clinical specimens and taxonomic revisions published in 2022
Authors: Munson Erik , Carella Arianna , Carroll Karen C. 
Published: October 2023

ABSTRACT

Although some nomenclature changes have caused consternation among clinical microbiologists, the discovery of novel taxa and improving classification of existing groups of organisms is exciting and adds to our understanding of microbial pathogenesis. In this mini-review, we present an in-depth summary of novel taxonomic designations and revisions to prokaryotic taxonomy that were published in 2022. Henceforth, these bacteriology taxonomic summaries will appear annually. Several of the novel Gram-positive organisms have been associated with disease, namely, the
Corynebacterium kroppenstedtii
-like organisms
Corynebacterium parakroppenstedtii
sp. nov. and
Corynebacterium pseudokroppenstedtii
sp. nov. A newly described
Streptococcus
species,
Streptococcus toyakuensis
sp. nov., is noteworthy for exhibiting multi-drug resistance. Among the novel Gram-negative pathogens,
Vibrio paracholerae
sp. nov. stands out as an organism associated with diarrhea and sepsis and has probably been co-circulating with pandemic
Vibrio cholerae
for decades. Many new anaerobic organisms have been described in this past year largely from genetic assessments of gastrointestinal microbiome collections. With respect to revised taxa, as discussed in previous reviews, the genus
Bacillus
continues to undergo further division into additional genera and reassignment of existing species into them. Reassignment of two subspecies of
Fusobacterium nucleatum
to species designations (
Fusobacterium animalis
sp. nov. and
Fusobacterium vincentii
sp. nov.) is also noteworthy. As was typical of previous reviews, literature updates for selected clinically relevant organisms discovered between 2017 and 2021 have been included.
Update on novel validly published taxa of bacteria isolated from domestic animals described in 2022
Authors: Lawhon Sara D. , Burbick Claire R. , Munson Erik , Thelen Elizabeth , Zapp Amanda , Wilson Anastasia 
Published: October 2023

ABSTRACT

Expansion of our knowledge of the microbial world continues to progress at a rapid rate and carries with it an associated need for recognizing and understanding the implications of those changes. Here, we describe additions of novel taxa from domestic animals published in 2022 that are validly published per the International Code of Nomenclature of Prokaryotes. These included new members of
Staphylococcaceae
,
Moraxella nasovis
sp. nov. in sheep with respiratory disease, three additions to
Campylobacteraceae
(including one from chickens with spotty liver disease), and multiple additions of organisms from the microbiota of dogs, pigs, and especially honeybees and other important pollinators. Noteworthy additions were associated with diseases of cattle, including mastitis, endocarditis, orchitis, and endometritis. Also described in 2022 was
Pseudochrobactrum algeriense
sp. nov., a member of the
Brucellaceae
family, isolated from the mammary lymph nodes of cows.
Benchmarking of virome metagenomic analysis approaches using a large, 60+ members, viral synthetic community
Authors: Schönegger Deborah , Moubset Oumaima , Margaria Paolo , Menzel Wulf , Winter Stephan , Roumagnac Philippe , Marais Armelle , Candresse Thierry 
Published: October 2023

ABSTRACT
In contrast to microbial metagenomics, there has still been only limited efforts to benchmark performance of virome analysis approaches in terms of faithfulness to community structure and of completeness of virome description. While natural communities are more readily accessible, synthetic communities assembled using well-characterized isolates allow more accurate performance evaluation. Starting from authenticated, quality-controlled reference isolates from the DSMZ Plant Virus Collection, we have assembled synthetic communities of varying complexity up to a highly complex community of 72 viral agents (115 viral molecules) comprising isolates from 21 viral families and 61 genera. These communities were then analyzed using two approaches frequently used in ecology-oriented plant virus metagenomics: a virion-associated nucleic acids (VANA)-based strategy and a highly purified double-stranded RNAs (dsRNAs)-based one. The results obtained allowed to compare diagnostic sensitivity of these two approaches for groups of viruses and satellites with different genome types and confirmed that the dsRNA-based approach provides a more complete representation of the RNA virome. However, for viromes of low to medium complexity, VANA appears a reasonable alternative and would be the preferred choiceif analysis of DNA viruses is of importance. They also allowed to identify several important parameters and to propose hypotheses to explain differences in performance, in particular, differences in the imbalance in the representation of individual viruses using each approach. Remarkably, these analyses highlight a strong direct relationship between the completeness of virome description and sample sequencing depth which should prove useful in further virome analysis efforts.

IMPORTANCE
We report here efforts to benchmark performance of two widespread approaches for virome analysis, which target either virion-associated nucleic acids (VANA) or highly purified double-stranded RNAs (dsRNAs). This was achieved using synthetic communities of varying complexity levels, up to a highly complex community of 72 viral agents (115 viral molecules) comprising isolates from 21 families and 61 genera of plant viruses. The results obtained confirm that the dsRNA-based approach provides a more complete representation of the RNA virome, in particular, for high complexity ones. However, for viromes of low to medium complexity, VANA appears a reasonable alternative and would be the preferred choice if analysis of DNA viruses is of importance. Several parameters impacting performance were identified as well as a direct relationship between the completeness of virome description and sample sequencing depth. The strategy, results, and tools used here should prove useful in a range of virome analysis efforts.