bluuebunny/crossref_metadata_2025_split huggingface dataset:
Individual and day‐to‐day differences in domain‐specific physical activity of 10‐ to 11‐year‐old children in Denmark—Measured using GPS and accelerometry
Authors: Stage Anna , Amholt Thea Toft , Schipperijn Jasper 
Published: April 2024

AbstractObjectivePhysical activity (PA) and the achievement of 60 min of moderate‐to‐physical‐activity daily is declining in school‐aged‐children, and effective strategies to increase PA is needed. We aimed to examine the individual and day‐to‐day distribution of PA on schooldays among children aged 10–11 in 4 domains—school, home, transport, and other.MethodsData were collected from August to September 2020 using accelerometer and GPS data to measure daily PA‐levels and to locate in which domain PA occurs. Daily PA‐levels were assessed in each domain, and analyses of the individual and day‐to‐day differences in PA‐levels were calculated.ResultsThe school domain contributed the most to children's daily MVPA with 47% of average MVPA, followed by the home domain with 26% of daily average MVPA, the other domain with 19% of daily average MVPA and the transport domain with 8% of daily average MVPA. Our results showed individual differences in where PA occurs, day‐to‐day differences in total MVPA and day‐to‐day differences in the MVPA‐levels across domains.ConclusionsThe school domain contributed the most to children's MVPA‐levels followed by the domains of home, other, and transport. Our study indicated that PA‐levels and the distribution of PA across domains differ from day‐to‐day. Future interventions should target more than one domain to accommodate these individual‐ and day‐to‐day differences in the goal of increasing PA‐levels and to reduce the decline in PA seen from childhood to adolescence.
Aggregates in apheresis‐derived platelet concentrates: A 5‐year single‐centre experience
Authors: Vinković Matea , Hećimović Ana , Jukić Irena , Vuk Tomislav 
Published: April 2024

AbstractBackground and ObjectivesThe phenomenon of aggregates in apheresis‐derived platelet concentrates (APCs) has not yet been fully elucidated. Initially, visible aggregates (IVA) usually dissolve within 24 h after collection, but some persist till the end of the shelf life (persistent aggregates, PA). A study conducted at the Croatian Institute of Transfusion Medicine aimed to identify factors that influence the aggregate occurrence in APCs.Materials and MethodsWe conducted a cross‐sectional study for the 2018–2022 period and collected data on APCs with IVA. We analysed APCs discarded due to PA separately for two apheresis technologies and compared them to the control group.ResultsSignificantly more donations were discarded in the IVA group compared with the control group and total number of discarded APCs. A total of 205 APCs were discarded due to PA (14.7% of IVA APCs and 1.27% of all APCs collected). Amicus APCs with PA had a significantly lower platelet count and mean platelet volume. They were obtained by procedures with less anticoagulant used. In contrast to Amicus APCs, Haemonetics APCs with PA had a significantly higher platelet count. None of the donor‐related factors examined was predictive of PA.ConclusionAPCs with IVA are more often discarded, not only due to aggregates, but also for impairment of other quality control parameters. Type of apheresis technology, being one of the most common risk factors for IVA, was not confirmed as the main risk factor for PA. There seem to be some donor‐related causal factors.
The development of Maltese English
Authors: Grech Sarah 
Published: April 2024

AbstractThere has been a more or less constant presence of the English language in the Maltese islands since British settlement began to establish itself during the 1800s. The necessity of accommodating foreign rulers or visitors fuelled a well‐established linguistic dexterity in the islanders, who are documented to have used what came to be designated as Maltese amongst themselves, alongside any other languages necessary with anyone else. Today, fluency in at least Maltese and English remains the preferred linguistic scenario, and both are generally considered necessary to be able to get involved in Maltese society.
Coxiella burnetii serostatus in dromedary camels (Camelus dromedarius) is associated with the presence of C. burnetii DNA in attached ticks in Laikipia County, Kenya
Authors: Rooney Tess , Fèvre Eric M. , Villinger Jandouwe , Brenn‐White Maris , Cummings Charles O. , Chai Daniel , Kamau Joseph , Kiyong'a Alice , Getange Dennis , Ochieng Dickens O. , Kivali Velma , Zimmerman Dawn , Rosenbaum Marieke , Nutter Felicia B. , Deem Sharon L. 
Published: April 2024

AbstractAimsQ fever is a globally distributed, neglected zoonotic disease of conservation and public health importance, caused by the bacterium Coxiella burnetii. Coxiella burnetii normally causes subclinical infections in livestock, but may also cause reproductive pathology and spontaneous abortions in artiodactyl species. One such artiodactyl, the dromedary camel (Camelus dromedarius), is an increasingly important livestock species in semi‐arid landscapes. Ticks are naturally infected with C. burnetii worldwide and are frequently found on camels in Kenya. In this study, we assessed the relationship between dromedary camels' C. burnetii serostatus and whether the camels were carrying C. burnetii PCR‐positive ticks in Kenya. We hypothesized that there would be a positive association between camel seropositivity and carrying C. burnetii PCR‐positive ticks.Methods and ResultsBlood was collected from camels (N = 233) from three herds, and serum was analysed using commercial ELISA antibody test kits. Ticks were collected (N = 4354), divided into pools of the same species from the same camel (N = 397) and tested for C. burnetii and Coxiella‐like endosymbionts. Descriptive statistics were used to summarize seroprevalence by camel demographic and clinical variables. Univariate logistic regression analyses were used to assess relationships between serostatus (outcome) and tick PCR status, camel demographic variables, and camel clinical variables (predictors). Camel C. burnetii seroprevalence was 52%. Across tick pools, the prevalence of C. burnetii was 15% and Coxiella‐like endosymbionts was 27%. Camel seropositivity was significantly associated with the presence of a C. burnetii PCR‐positive tick pool (OR: 2.58; 95% CI: 1.4–5.1; p = 0.0045), increasing age class, and increasing total solids.ConclusionsThe role of ticks and camels in the epidemiology of Q fever warrants further research to better understand this zoonotic disease that has potential to cause illness and reproductive losses in humans, livestock, and wildlife.
Dynamic cerebral autoregulation is governed by two time constants: Arterial transit time and feedback time constant
Authors: Payne Stephen J. 
Published: April 2024

AbstractDynamic cerebral autoregulation (dCA) is the mechanism that describes how the brain maintains cerebral blood flow approximately constant in response to short‐term changes in arterial blood pressure. This is known to be impaired in many different pathological conditions, including ischaemic and haemorrhagic stroke, dementia and traumatic brain injury. Many different approaches have thus been used both to analyse and to quantify this mechanism in a range of healthy and diseased subjects, including data‐driven models (in both the time and the frequency domain) and biophysical models. However, despite the substantial body of work on both biophysical models and data‐driven models of dCA, there remains little work that links the two together. One of the reasons for this is proposed to be the discrepancies between the time constants that govern dCA in models and in experimental data. In this study, the processes that govern dCA are examined and it is proposed that the application of biophysical models remains limited due to a lack of understanding about the physical processes that are being modelled, partly due to the specific model formulation that has been most widely used (the equivalent electrical circuit). Based on the analysis presented here, it is proposed that the two most important time constants are arterial transit time and feedback time constant. It is therefore time to revisit equivalent electrical circuit models of dCA and to develop a more physiologically realistic alternative, one that can more easily be related to experimental data.
imageKey points
Dynamic cerebral autoregulation is governed by two time constants.
The first time constant is the arterial transit time, rather than the traditional ‘RC’ time constant widely used in previous models.
This arterial transit time is approximately 1 s in the brain.
The second time constant is the feedback time constant, which is less accurately known, although it is somewhat larger than the arterial transit time.
The equivalent electrical circuit model of dynamic cerebral autoregulation should be replaced with a more physiologically representative model.
Calcineurin regulates synaptic Ca2+‐permeable AMPA receptors in hypothalamic presympathetic neurons via α2δ‐1‐mediated GluA1/GluA2 assembly
Authors: Zhou Jing‐Jing , Shao Jian‐Ying , Chen Shao‐Rui , Chen Hong , Pan Hui‐Lin 
Published: April 2024

AbstractHypertension is a major adverse effect of calcineurin inhibitors, such as tacrolimus (FK506) and cyclosporine, used clinically as immunosuppressants. Calcineurin inhibitor‐induced hypertension (CIH) is linked to augmented sympathetic output from the hypothalamic paraventricular nucleus (PVN). GluA2‐lacking, Ca2+‐permeable AMPA receptors (CP‐AMPARs) are a key feature of glutamatergic synaptic plasticity, yet their role in CIH remains elusive. Here, we found that systemic administration of FK506 in rats significantly increased serine phosphorylation of GluA1 and GluA2 in PVN synaptosomes. Strikingly, FK506 treatment reduced GluA1/GluA2 heteromers in both synaptosomes and endoplasmic reticulum‐enriched fractions from the PVN. Blocking CP‐AMPARs with IEM‐1460 induced a larger reduction of AMPAR‐mediated excitatory postsynaptic current (AMPAR‐EPSC) amplitudes in retrogradely labelled, spinally projecting PVN neurons in FK506‐treated rats than in vehicle‐treated rats. Furthermore, FK506 treatment shifted the current–voltage relationship of AMPAR‐EPSCs from linear to inward rectification in labelled PVN neurons. FK506 treatment profoundly enhanced physical interactions of α2δ‐1 with GluA1 and GluA2 in the PVN. Inhibiting α2δ‐1 with gabapentin, α2δ‐1 genetic knockout, or disrupting α2δ‐1–AMPAR interactions with an α2δ‐1 C terminus peptide restored GluA1/GluA2 heteromers in the PVN and diminished inward rectification of AMPAR‐EPSCs in labelled PVN neurons induced by FK506 treatment. Additionally, microinjection of IEM‐1460 or α2δ‐1 C terminus peptide into the PVN reduced renal sympathetic nerve discharges and arterial blood pressure elevated in FK506‐treated rats but not in vehicle‐treated rats. Thus, calcineurin in the hypothalamus constitutively regulates AMPAR subunit composition and phenotypes by controlling GluA1/GluA2 interactions with α2δ‐1. Synaptic CP‐AMPARs in PVN presympathetic neurons contribute to augmented sympathetic outflow in CIH.
imageKey points
Systemic treatment with the calcineurin inhibitor increases serine phosphorylation of synaptic GluA1 and GluA2 in the PVN.
Calcineurin inhibition enhances the prevalence of postsynaptic Ca2+‐permeable AMPARs in PVN presympathetic neurons.
Calcineurin inhibition potentiates α2δ‐1 interactions with GluA1 and GluA2, disrupting intracellular assembly of GluA1/GluA2 heterotetramers in the PVN.
Blocking Ca2+‐permeable AMPARs or α2δ‐1–AMPAR interactions in the PVN attenuates sympathetic outflow augmented by the calcineurin inhibitor.
Two-Fluid and Discrete Element Modeling of a Parallel Plate Fluidized Bed Heat Exchanger for Concentrating Solar Power
Authors: Appaswamy Krutika , Schirck Jason , Punchi Wedikkara Chathusha , Morris Aaron , Ma Zhiwen 
Published: April 2024

Abstract
A novel high-temperature particle solar receiver is developed using a light trapping planar cavity configuration. As particles fall through the cavity, the concentrated solar radiation warms the boundaries of the receiver and in turn heats the particles. Particles flow through the system, forming a fluidized bed at the lower section, leaving the system from the bottom at a constant flowrate. Air is introduced to the system as the fluidizing medium to improve particle heat transfer and mixing. A laboratory scale cavity receiver is built by collaborators at the Colorado School of Mines and their data are used for model validation. In this experimental setup, near IR quartz lamp is used to provide flux to the vertical wall of the heat exchanger. The system is modeled using the discrete element method and a continuum two-fluid method. The computational model matches the experimental system size and the particle size distribution is assumed monodisperse. A new continuum conduction model that accounts for the effects of solid concentration is implemented, and the heat flux boundary condition matches the experimental setup. Radiative heat transfer is estimated using a widely used correlation during the post-processing step to determine an overall heat transfer coefficient. The model is validated against testing data and achieves less than 30% discrepancy and a heat transfer coefficient greater than 1000 W/m2 K.
A Separation Modeling Method for Morphing QUAV: Analytical Solutions for Constraint Forces Under Deformation
Authors: Dong Fangfang , Yuan Baotao , Zhao Xiaomin , Chen Ye-Hwa , Chen Shan 
Published: April 2024

Abstract
A morphing quadrotor unmanned aerial vehicle (QUAV) possesses the remarkable ability to alter its shape, enabling it to navigate through gaps smaller than its wingspan. However, these deformations result in changes to the system's center of gravity and moment of inertia, necessitating real-time computation of each state's variations. To address this challenge, we propose a dynamic modeling approach based on the Udwadia−Kalaba (U-K) method. The morphing QUAV is divided into three separate subsystems, with the dynamic modeling for each subsystem conducted independently. Subsequently, the QUAV's deformation states and inherent structure are introduced in the form of constraints, and the constrained forces are derived using the U-K equation. By combining these analytical solutions, the model of the QUAV under continuous deformation is obtained. This approach effectively simplifies the modeling computations caused by changes in the system's center of gravity and moment of inertia during deformation. A control approach is proposed to achieve attitude stabilization and altitude control for the morphing QUAV. Ultimately, the stable motion of the morphing QUAV is validated through numerical simulations.
Investigation of Fiber Orientation of Fused Filament Fabricated CFRP Composites via an External Magnetic Field
Authors: Zhang Haoran , Wang Kaifeng 
Published: April 2024

Abstract
For carbon fiber-reinforced plastic (CFRP) composites, controlling the interior fiber distribution and orientation during the manufacturing process is a common approach to optize the structural performance of fabricated parts. However, few studies have been conducted to investigate fiber alignment during the additive manufacturing of CFRP composites. This study proposes a magnetic field controlled (MFC) method to control the fiber orientation during the fused filament fabrication (FFF) of nickel-coated carbon fiber (NCF) reinforced polymer composites. Firstly, a theoretical analysis model is established to explore the suitable magnetic field intensity for fiber rotation. Secondly, a customized FFF system with MFC components is implemented, and a polylactic acid matrix composite containing 10 wt% NCF is printed to validate the feasibility of the proposed approach. The microstructure of the printed samples is examined to assess the effectiveness of the method. Finally, uniaxial tensile tests are performed to investigate the impact of fiber orientation adjustment on mechanical properties. The experimental results reveal that the MFC method can effectively align the interior fiber orientation of CFRP composites, leading to a significant increase in the tensile strength (approximately 8.8%) and Young's modulus (around 10.5%) of the printed samples.
Antibacterial insights into alternariol and its derivative alternariol monomethyl ether produced by a marine fungus
Authors: Li Rongmei , Su Zhenjie , Sun Chaomin , Wu Shimei 
Published: April 2024

ABSTRACT

Alternaria alternata
FB1 is a marine fungus identified as a candidate for plastic degradation in our previous study. This fungus has been recently shown to produce secondary metabolites with significant antimicrobial activity against various pathogens, including methicillin-resistant
Staphylococcus aureus
(MRSA) and the notorious aquaculture pathogen
Vibrio anguillarum
. The antibacterial compounds were purified and identified as alternariol (AOH) and its derivative, alternariol monomethyl ether (AME). We found that AOH and AME primarily inhibited pathogenic bacteria (MRSA or
V. anguillarum
) by disordering cell division and some other key physiological and biochemical processes. We further demonstrated that AOH could effectively inhibit the unwinding activity of MRSA topoisomerases, which are closely related to cell division and are the potential action target of AOH. The antibacterial activities of AOH and AME were verified by using zebrafish as the
in vivo
model. Notably, AOH and AME did not significantly affect the viability of normal human liver cells at concentrations that effectively inhibited MRSA or
V. anguillarum
. Finally, we developed the genetic operation system of
A. alternata
FB1 and blocked the biosynthesis of AME by knocking out
omtI
(encoding an O-methyl transferase), which facilitated
A. alternata
FB1 to only produce AOH. The development of this system in the marine fungus will accelerate the discovery of novel natural products and further bioactivity study.

IMPORTANCE

More and more scientific reports indicate that alternariol (AOH) and its derivative alternariol monomethyl ether (AME) exhibit antibacterial activities. However, limited exploration of their detailed antibacterial mechanisms has been performed. In the present study, the antibacterial mechanisms of AOH and AME produced by the marine fungus
Alternaria alternata
FB1 were disclosed
in vitro
and
in vivo
. Given their low toxicity on the normal human liver cell line under the concentrations exhibiting significant antibacterial activity against different pathogens, AOH and AME are proposed to be good candidates for developing promising antibiotics against methicillin-resistant
Staphylococcus aureus
and
Vibrio anguillarum
. We also succeeded in blocking the biosynthesis of AME, which facilitated us to easily obtain pure AOH. Moreover, based on our previous results,
A. alternata
FB1 was shown to enable polyethylene degradation.
Bacterial surface lipoproteins mediate epithelial microinvasion by
Streptococcus pneumoniae
Authors: Chan Jia Mun , Ramos-Sevillano Elisa , Betts Modupeh , Wilson Holly U. , Weight Caroline M. , Houhou-Ousalah Ambrine , Pollara Gabriele , Brown Jeremy S. , Heyderman Robert S. 
Published: April 2024

ABSTRACT

Streptococcus pneumoniae
, a common colonizer of the upper respiratory tract, invades nasopharyngeal epithelial cells without causing disease in healthy participants of controlled human infection studies. We hypothesized that surface expression of pneumococcal lipoproteins, recognized by the innate immune receptor TLR2, mediates epithelial microinvasion. Mutation of
lgt
in serotype 4 (TIGR4) and serotype 6B (BHN418) pneumococcal strains abolishes the ability of the mutants to activate TLR2 signaling. Loss of
lgt
also led to the concomitant decrease in interferon signaling triggered by the bacterium. However, only BHN418
lgt::cm
but not TIGR4
lgt::cm
was significantly attenuated in epithelial adherence and microinvasion compared to their respective wild-type strains. To test the hypothesis that differential lipoprotein repertoires in TIGR4 and BHN418 lead to the intraspecies variation in epithelial microinvasion, we employed a motif-based genome analysis and identified an additional 525 a.a. lipoprotein (
p
neumococcal
a
ccessory
l
ipoprotein
A
;
palA
) encoded by BHN418 that is absent in TIGR4. The gene encoding
palA
sits within a putative genetic island present in ~10% of global pneumococcal isolates. While
palA
was enriched in the carriage and otitis media pneumococcal strains, neither mutation nor overexpression of the gene encoding this lipoprotein significantly changed microinvasion patterns. In conclusion, mutation of
lgt
attenuates epithelial inflammatory responses during pneumococcal-epithelial interactions, with intraspecies variation in the effect on microinvasion. Differential lipoprotein repertoires encoded by the different strains do not explain these differences in microinvasion. Rather, we postulate that post-translational modifications of lipoproteins may account for the differences in microinvasion.

IMPORTANCE

Streptococcus pneumoniae
(pneumococcus) is an important mucosal pathogen, estimated to cause over 500,000 deaths annually. Nasopharyngeal colonization is considered a necessary prerequisite for disease, yet many people are transiently and asymptomatically colonized by pneumococci without becoming unwell. It is therefore important to better understand how the colonization process is controlled at the epithelial surface. Controlled human infection studies revealed the presence of pneumococci within the epithelium of healthy volunteers (microinvasion). In this study, we focused on the regulation of epithelial microinvasion by pneumococcal lipoproteins. We found that pneumococcal lipoproteins induce epithelial inflammation but that differing lipoprotein repertoires do not significantly impact the magnitude of microinvasion. Targeting mucosal innate immunity and epithelial microinvasion alongside the induction of an adaptive immune response may be effective in preventing pneumococcal colonization and disease.
Effectiveness of repeated low-level red light in myopia prevention and myopia control
Authors: Liu Guihua , Rong Hua , Liu Yipu , Wang Biying , Du Bei , Song Desheng , Wei Ruihua 
Published: April 2024

Background/aimsTo compare the effects of repeated low-level red light (RLRL) treatment on axial length growth and refractive error changes in myopic and premyopic children.MethodsSubjects were assigned randomly to four subgroups: myopia-RLRL group (M-RL), myopia-control group (M-C), premyopia-RLRL group (PM-RL) and premyopia-control group (PM-C). Subjects in the RLRL group completed a 12-month treatment composed of a 3 min RLRL treatment session twice daily, with an interval of at least 4 hours, for 7 days per week. Visits were scheduled before and at 1-month, 3-month, 6-month, 9-month and 12-month follow-up after the treatment. Repeated-measures analysis of variance was used to compare the spherical equivalent refractive errors (SE) and axial length (AL) changes between the groups across the treatment period.ResultsAfter 12 months of treatment, in the myopia group, SE and AL changes were −0.078±0.375 D and 0.033±0.123 mm for M-RL and −0.861±0.556 D and 0.415±0.171 mm for M-C; in the premyopia group, the progression of SE and AL was −0.181±0.417 D and 0.145±0.175 mm for PM-RL and −0.521±0.436 D and 0.292±0.128 mm for PM-C. PM-RL indicated a lower myopia incidence than PM-C (2.5% vs 19.4%). Additionally, the percentage of AL shortening in the M-RL was higher than that in the PM-RL before the 9-month follow-up.ConclusionRLRL effectively delayed myopia progression in children with myopia and reduced the incidence of myopia in premyopic children. Moreover, RLRL exhibited a stronger impact on myopic children compared with premyopic individuals.