bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Scavenging-Port Semi-Direct Injection Strategy on Mixture Formation for a Two-Stroke Spark-Ignition Kerosene Piston Engine
Authors: Liu Rui , Li Songhong , Liu Siyu , Zhong Lingfeng , Chen Yufeng , Li Jing 
Published: November 2024

Abstract
The two-stroke spark-ignition (SI) kerosene piston engines (KPE) are commonly utilized in lightweight unmanned aerial vehicles. The quality of mixture formation is crucial for the engine performance. This paper investigates the mixture quality in a semi-direct injection (SDI) SI KPE. Computational models were established using a 1D simulation tool and a 3D computational platform to analyze the effects of injection pressure, injection timing, and fuel temperature on atomization and mixture formation. The results indicate that increasing injection pressure promotes a more uniform mixture distribution. Higher injection pressures also enhance the formation of fuel film. At the top dead center (TDC), the average equivalence ratio (ER) with an injection pressure of 0.7 MPa is 3.8% higher than that of 0.3 MPa and 1.9% lower than that of 0.5 MPa. Delaying the injection timing increases the pressure difference between the cylinder and scavenging port, weakening fuel penetration and improving the fuel gasification rate. When the injection timing is set to 180 °CA ATDC, the average ER at TDC is 10.4% higher than that at 140 °CA ATDC, with a 6.6% decrease in fuel capture rate. Increasing fuel temperature effectively enhances the fuel gasification rate. However, excessively higher fuel temperatures will not significantly improve mixture quality. At a fuel temperature of 380 K, the average ER at TDC is 2.9% higher than that at 340 K. Response surface analysis reveals that the control parameters affect the average ERs in the following order of influence: injection timing, fuel temperature, and injection pressure. This study provides theoretical support for optimizing control parameters in SDI SI KPEs.
Switching Events of Wakes Shed From Two Short Flapping Side-by-Side Cylinders
Authors: Wang Yong Pu , Atkins Michael D. , Lu Tian Jian , Kim Tongbeum 
Published: November 2024

Abstract
The wakes shed alternatively from two long stationary side-by-side cylinders have long been an issue in many engineering applications, such as wind energy harvesting schemes that utilize vortex-induced vibrations (VIVs). In this study, switching events of the wakes shed from two “short,” “flapping” side-by-side cylinders are investigated. To this end, the flow visualization and spectral analysis of the time-resolved data from hot-wire anemometers and the piezoelectric mount of flapping cylinders are carried out. Measurements are conducted with differing center-to-center spacing normalized by a single cylinder diameter (T/D)—gap ratio, and length-to-diameter ratio (L/D) in a Reynolds number range of 800 ≤ ReD ≤ 16,000. The results demonstrate the transition of wake shedding patterns, sequentially from a single bluff body wake, first bistable wakes, tristable wakes, second bistable wakes, and eventually to coupled wakes as the gap ratio is increased. Furthermore, the role of shortness and flapping of the two cylinders in determining the wake kinematics is elucidated, and the transitional sequences and switching of dominant shedding frequencies are detailed.
Association Between Objective Sleep and Clinical Outcomes in Older Adults With Low Back Pain Receiving Physical Therapy Care: A Secondary Analysis of a Responsiveness Study
Authors: Silva Samuel , Pinto Rafael Zambelli , Mendes Gabriel , Santos Raimundo Lucas , Grade Isadora , de Mello Marco Túlio , Hayden Jill A. , Silva Andressa 
Published: November 2024

Background/Objectives: Sleep seems to be associated with worse low back pain (LBP) outcomes in older adults; however, studies investigating the association of objective sleep with future changes in LBP outcomes are lacking. The objectives of this study are as follows: (a) to investigate the association between objectively measured sleep with changes in clinical outcomes in older adults with LBP receiving physical therapy care and (b) to examine the cross-sectional association between sleep and pain catastrophizing. Methods: This was a prospective cohort study. We recruited older adults (≥60 years old) with chronic LBP undergoing physical therapy treatment. At baseline, we assessed participants’ sleep (actigraphy for 10–14 days), pain intensity, disability, pain catastrophizing, and covariates. After 8 weeks, we reassessed pain intensity, disability, and self-perceived recovery. We ran linear regression models and Spearman coefficient tests. Results: Fifty-eight participants were included, and 51 completed follow-up assessments (60.8% women; mean age 70.1 ± 5.6 years). We found no associations between sleep quantity and efficiency with changes in pain intensity, disability, and self-perceived recovery after 8 weeks of physical therapy care. We found a correlation between sleep fragmentation and pain catastrophizing (r = .30; 95% confidence interval: [.03, .54]). Conclusion: Objective sleep quantity and efficiency may not be associated with changes in LBP outcomes after physical therapy care in older adults. Among the sleep domains evaluated, sleep fragmentation may be the sleep domain with the strongest association with pain catastrophizing. Significance/Implications: Objectively measured sleep might not be a prognostic factor for LBP improvement in older adults. Future studies should explore the association between sleep fragmentation and pain catastrophizing.
Inactivation of checkpoint kinase 1 (Chk1) during parvovirus minute virus of mice (MVM) infection inhibits cellular homologous recombination repair and facilitates viral genome replication
Authors: Etingov Igor , Pintel David J. 
Published: November 2024

ABSTRACT

During infection, the autonomous parvovirus minute virus of mice (MVM) induces cellular DNA breaks and localizes to such sites, which presumably affords an environment beneficial for genome replication. MVM replication also benefits from the DNA damage response (DDR) mediated by the ataxia-telangiectasia mutated (ATM) kinase, while the ataxia telangiectasia and Rad-3 related (ATR) arm of the DDR is disabled, which prevents activation of its primary target, checkpoint kinase 1 (Chk1). We find here that Chk1 inactivation strongly correlates with dephosphorylation of one of its targets, RAD51, known to play a pivotal role in homologous recombination repair (HRR), thus leading to substantial inhibition of DNA repair in infected cells. We demonstrate colocalization of replicating MVM DNA with cellular double-strand breaks (DSBs) during infection, and show that an agent that exogenously induces cellular DSBs significantly increases viral DNA replication levels, establishing a role for cellular genome damage in facilitating virus DNA replication. Additionally, overexpression of active Chk1 during MVM infection was found to re-establish the activating phosphorylation of RAD51 Thr 309, significantly suppress infection-induced reduction of HRR efficiency with a concomitant increase in cellular genome DSBs, and reduce viral DNA replication levels. Thus, we conclude that during infection, MVM inhibition of Chk1 activation enhances viral replication, at least in part, by inhibiting cellular HRR.

IMPORTANCE
The autonomous parvovirus minute virus of mice (MVM) has a compact DNA genome encoding a minimum number of proteins. During infection, it induces cellular DNA damage and both utilizes and modifies the subsequent cellular DNA damage response (DDR) in various ways to facilitate its replication. One of MVM’s activities in this regard is to inhibit one of the primary arms of the DDR, the ataxia telangiectasia and Rad-3 related (ATR) pathway, which prevents activation of checkpoint kinase 1 (Chk1), a key protein involved in controlling the cellular DDR and preserving genome integrity. We show that prevention by MVM of Chk1 activation leads to inhibition of homologous recombination repair (HRR) of cellular DNA, which helps sustain viral replication. This work illuminates another way in which autonomous parvoviruses adjust the cellular environment for their replicative advantage.
Antibiotic resistant bacteria survive treatment by doubling while shrinking
Authors: Campey Adrian , Łapińska Urszula , Chait Remy , Tsaneva-Atanasova Krasimira , Pagliara Stefano 
Published: November 2024

ABSTRACT

Many antibiotics that are used in healthcare, farming, and aquaculture end up in environments with different spatial structures that might promote heterogeneity in the emergence of antibiotic resistance. However, the experimental evolution of microbes at sub-inhibitory concentrations of antibiotics has been mainly carried out at the population level which does not allow capturing single-cell responses to antibiotics. Here, we investigate and compare the emergence of resistance to ciprofloxacin in
Escherichia coli
in well-mixed and structured environments using experimental evolution, genomics, and microfluidics-based time-lapse microscopy. We discover that resistance to ciprofloxacin and cross-resistance to other antibiotics is stronger in the well-mixed environment due to the emergence of target mutations, whereas efflux regulator mutations emerge in the structured environment. The latter mutants also harbor sub-populations of persisters that survive high concentrations of ciprofloxacin that inhibit bacterial growth at the population level. In contrast, genetically resistant bacteria that display target mutations also survive high concentrations of ciprofloxacin that inhibit their growth via population-level antibiotic tolerance. These resistant and tolerant bacteria keep doubling while shrinking in size in the presence of ciprofloxacin and regain their original size after antibiotic removal, which constitutes a newly discovered phenotypic response. This new knowledge sheds light on the diversity of strategies employed by bacteria to survive antibiotics and poses a stepping stone for understanding the link between mutations at the population level and phenotypic single-cell responses.

IMPORTANCE
The evolution of antimicrobial resistance poses a pressing challenge to global health with an estimated 5 million deaths associated with antimicrobial resistance every year globally. Here, we investigate the diversity of strategies employed by bacteria to survive antibiotics. We discovered that bacteria evolve genetic resistance to antibiotics while simultaneously displaying tolerance to very high doses of antibiotics by doubling while shrinking in size.
Complete genome sequence of
Sporosarcina pasteurii
type strain DSM33
Authors: Tuttle Matthew J. , Stamps Blake W. , Chodkowski John L. , Mechan-Llontop Marco E. , Shade Ashley , Hung Chia-Suei , Gupta Maneesh K. , Carter Michael S. 
Published: November 2024

ABSTRACT

Here, we present the complete genome sequence of
Sporosarcina pasteurii
type strain DSM33, a model organism for microbially induced calcium carbonate precipitation. This genome consists of a single 3.3-Mb chromosome and is an improvement upon draft
S. pasteurii
genome sequences currently available in public databases.
Neutrophil prime unique transcriptional responses in intestinal organoids during infection with nontyphoidal
Salmonella enterica
serovars
Authors: Lawrence Anna-Lisa E. , Berger Ryan P. , Hill David R. , Huang Sha , Yadagiri Veda K. , Bons Brooke , Fields Courtney , Knight Jason S. , Wobus Christiane E. , Spence Jason R. , Young Vincent B. , Abuaita Basel H. , O'Riordan Mary X. 
Published: November 2024

ABSTRACT

Nontyphoidal strains of
Salmonella enterica
are a major cause of foodborne illnesses, and infection with these bacteria results in inflammatory gastroenteritis. Polymorphonuclear leukocytes (PMNs), also known as neutrophils, are a dominant immune cell type found at the site of infection in
Salmonella-
infected individuals, but how they regulate infection outcome is not well understood. Here, we used a co-culture model of primary human PMNs and human intestinal organoids to probe the role of PMNs during infection with two of the most prevalent
Salmonella
serovars:
Salmonella enterica
serovar Enteritidis and Typhimurium. Using a transcriptomics approach, we identified a dominant role for PMNs in mounting differential immune responses including production of pro-inflammatory cytokines, chemokines, and antimicrobial peptides. We also identified specific gene sets that were induced by PMNs in response to Enteritidis or Typhimurium infection. By comparing host responses to these serovars, we uncovered differential regulation of host metabolic pathways particularly induction of cholesterol biosynthetic pathways during Typhimurium infection and suppression of RNA metabolism during Enteritidis infection. Together, these findings provide insight into the role of human PMNs in modulating different host responses to pathogens that cause similar disease in humans.

IMPORTANCE

Nontyphoidal serovars of
Salmonella enterica
are known to induce robust recruitment of polymorphonuclear leukocytes (PMNs) in the gut during early stages of infection, but the specific role of PMNs in regulating infection outcome of different serovars is poorly understood. Due to differences in human infection progression compared to small animal models, characterizing the role of PMNs during infection has been challenging. Here, we used a co-culture model of human intestinal organoids with human primary PMNs to study the role of PMNs during infection of human intestinal epithelium. Using a transcriptomics approach, we define PMN-dependent reprogramming of the host response to
Salmonella
, establishing a clear role in amplifying pro-inflammatory gene expression. Additionally, the host response driven by PMNs differed between two similar nontyphoidal
Salmonella
serovars. These findings highlight the importance of building more physiological infection models to replicate human infection conditions to study host responses specific to individual pathogens.
Investigation of choroidal vascular alterations in eyes with myopia using ultrawidefield optical coherence tomography angiography
Authors: Tang Xiangcheng , Liang Jia , Luo Lishi , Yuan Fanglan , Zhao Keming , Zhuo Xiaohua , Li Wangting , Wang Jiantao , Zhang Shaochong , Zeng Kun 
Published: November 2024

Background/aimsThe study aims to evaluate choroidal vascular changes in younger patients with myopia using ultrawidefield swept-source optical coherence tomography angiography (SS-OCTA).MethodsOverall, 724 eyes of 362 participants (177 males, 185 females, age: 32.43±6.20 years) underwent SS-OCTA imaging (24×20 mm). The eyes were divided into normal, low myopia (LM), moderate myopia (MM), high myopia and superhigh myopia groups according to the spherical equivalent refraction (SER). Changes in choroidal vascular thickness (ChVT) and density (ChVD) in nine grids of the fundus were analysed using the latest version of the built-in analysis software.ResultsAxial length (AL) showed a negative correlation with SER (r=0.822, p=0.000); ChVT and ChVD showed a negative correlation with AL (p≤0.001) in all nine grids. In group analysis, compared with normal eyes, myopia affects ChVT earlier than ChVD, as observed in the LM and MM groups, respectively. The decrease in ChVT was most evident in the macular grid (β= −34.20, p=0.000), whereas the decrease in ChVD was most evident in the optic disc grid (β= −2.19, p=0.001).ConclusionMyopia has a significant impact on choroidal vascular structure, resulting in spatiotemporal differences. Using SS-OCTA with a new version of the built-in analysis software and a study with a larger sample cohort may aid in providing more authentic information on choroidal vascular changes in eyes with myopia.
TNFR2 blockade promotes antitumoral immune response in PDAC by targeting activated Treg and reducing T cell exhaustion
Authors: Debesset Anais , Pilon Caroline , Meunier Sylvain , Cuelenaere-Bonizec Orianne , Richer Wilfrid , Thiolat Allan , Houppe Claire , Ponzo Matteo , Magnan Jeanne , Caron Jonathan , Caudana Pamela , Tosello Boari Jimena , Baulande Sylvain , To Nhu Han , Salomon Benoit Laurent , Piaggio Eliane , Cascone Ilaria , Cohen José Laurent 
Published: November 2024

BackgroundPancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive cancers, highly resistant to standard chemotherapy and immunotherapy. Regulatory T cells (Tregs) expressing tumor necrosis factor α receptor 2 (TNFR2) contribute to immunosuppression in PDAC. Treg infiltration correlates with poor survival and tumor progression in patients with PDAC. We hypothesized that TNFR2 inhibition using a blocking monoclonal antibody (mAb) could shift the Treg-effector T cell balance in PDAC, thus enhancing antitumoral responses.MethodTo support this hypothesis, we first described TNFR2 expression in a cohort of 24 patients with PDAC from publicly available single-cell analysis data. In orthotopic and immunocompetent mouse models of PDAC, we also described the immune environment of PDAC after immune cell sorting and single-cell analysis. The modifications of the immune environment before and after anti-TNFR2 mAb treatment were evaluated as well as the effect on tumor progression.ResultsPatients with PDAC exhibited elevated TNFR2 expression in Treg, myeloid cells and endothelial cells and lower level in tumor cells. By flow cytometry and single-cell RNA-seq analysis, we identified two Treg populations in orthotopic mouse models: Resting and activated Tregs. The anti-TNFR2 mAb selectively targeted activated tumor-infiltrating Tregs, reducing T cell exhaustion markers in CD8+T cells. However, anti-TNFR2 treatment alone had limited efficacy in activating CD8+T cells and only slightly reduced the tumor growth. The combination of the anti-TNFR2 mAb with agonistic anti-CD40 mAb promoted stronger T cell activation, tumor growth inhibition, and improved survival and immunological memory in PDAC-bearing mice.ConclusionOur data suggest that combining a CD40 agonist with a TNFR2 antagonist represents a promising therapeutic strategy for patients with PDAC.
Associations between objectively measured nighttime sleep duration, sleep timing, and sleep quality and body composition in toddlers in the Guelph Family Health Study
Authors: Ribey Sarah C.S. , Coyle-Asbil Hannah J. , Osojnicki Katarina , Coyle-Asbil Bridget , Vallis Lori Ann , Darlington Gerarda , Duncan Alison M. , Ma David W.L. , Haines Jess , Buchholz Andrea C. 
Published: November 2024

The prevalence of child obesity is a worldwide public health concern. Good sleep quality is associated with reduced adiposity in older children and adults. More research is needed in younger children to help mitigate risk of obesity. In addition, we aimed to address limitations found in previous studies such as relying on subjective measures, or only including one parameter of sleep, using only one body composition parameter, and/or not adjusting for relevant covariates. This cross-sectional study examined baseline data from 48 toddlers aged 1 to <3 years enrolled in the Guelph Family Health Study. Nighttime sleep duration (total sleep time; TST), sleep timing (sleep onset and offset time), and sleep quality (wake after sleep onset; WASO) were measured using 24 h accelerometry for 7 consecutive days. Height, body weight, and waist circumference were measured, and BMI z-scores and waist-to-height ratios were calculated. Percent fat mass and fat mass index were calculated using bioelectrical impedance analysis. Linear regression models were used to estimate associations between sleep parameters and body composition outcomes, with adjustments for relevant covariates (age, sex, household income, screen time, energy intake, physical activity, household stress). Nighttime sleep onset time was positively associated with waist-to-height ratio ([Formula: see text] = 0.004, p = 0.04). Sleep offset time was negatively associated with BMI z-score ([Formula: see text] = −0.48, p = 0.02). TST and WASO were not associated with any body composition outcome. Building healthy sleep habits may prevent childhood obesity; longitudinal research in a larger sample is warranted. This study was registered on ClinicalTrials.gov (NCT02939261).
Field investigation on the performance of low-carbon MgO-carbonated composite piles for ground treatments
Authors: Liu Yi-Zhao , Liu Song-Yu , Li Hong-Jiang , Du Guang-Yin , Zhang Chao-Zhe , Sun Jia-Wei 
Published: November 2024

Carbonation technology using MgO and CO2 has been considered a rapid, effective, and environmentally friendly method for improving weak soils, mainly applied in shallow foundation treatments. This study introduced a novel MgO-carbonated composite pile (MCP) technique developed by injecting CO2 through a gas-permeable pipe pile into a MgO-mixing column for carbonation and solidification and its applications in weak subgrade treatments. Several field tests were carried out to study the characteristics of MCP as well as the performance of the MCP-reinforced foundations, including carbonation reaction temperature monitoring, pore-water pressure monitoring, standard penetration tests (SPTs), unconfined compressive strength (UCS) tests, static load tests, and subgrade deformation monitoring. Results showed vigorous and uniform carbonation within the MgO-mixing column, confirming the feasibility of constructing large-diameter MgO-mixing columns. The distribution, evolution, and affected zone of excess pore-water pressure induced by MCP installation were determined. The MCP exhibited good pile quality, with average SPT blow count and UCS value of 39 and 1021 kPa, respectively. MCP’s bearing capacity was superior to prestressed high-strength concrete pipe piles, with ultimate vertical and lateral bearing capacities of 1920 and 119 kN, respectively. The MCP-reinforced foundation exhibited a small settlement of 54.5 mm under embankment loads. Life cycle assessment indicated significant carbon reduction benefits for MCP, with 44.7% lower carbon emissions compared to traditional composite piles.
Evaluation of rapidly mutating Y-short tandem repeats in distinguishing genetic variations
Authors: Ullah Muhammad Farhat , Khan Muhammad Ramzan , Ijaz Khan M. 
Published: November 2024

The Y chromosome contains short tandem repeats (STRs) that have numerous applications, including forensic investigations, male identification for legal purposes, and population genetics. However, commercially available Y-STR tests have limitations in their ability to differentiate closely linked male individuals in forensic genetics. Recent studies have shown that rapidly mutating (RM) Y-STRs offer significantly greater haplotype diversity across worldwide populations than conventional Y-STRs, although some RM Y-STR loci are not included in current commercial kits. This research aimed to evaluate the effectiveness of RM Y-STR haplotype frequencies in distinguishing individuals with genetic variations in the Gilgit population and other Pakistani populations. The study involved analyzing several RM Y-STRs in 56 unrelated Gilgit men and 21 other Pakistani populations. Statistical analysis showed that most of the loci maintained haplotype values, while some varied in certain cases. The results indicated that RM Y-STRs were highly effective in distinguishing genetic differences among the Gilgit population and other Pakistani populations, as evidenced by the gene diversity (GD), average GD and discrimination capacity (DC), match probability (MP), and power discrimination (PD) values calculated for the set of various RM Y-STRs in Table 1 for the Gilgit population and in Table 2 for other Pakistani populations. These findings highlight the potential of RM Y-STRs in forensic genetics and population genetics research and underscore the importance of including a diverse set of loci to maximize the discriminatory power of genetic markers. Further research could explore the utility of RM Y-STRs in other populations and their potential for use in other applications beyond forensic investigations and male identification.