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Multi-omics and AI-driven immune subtyping to optimize neoantigen-based vaccines for colorectal cancer
The saturation effect of a body shape index on lumbar bone mineral density in US adults: Findings from a nationwide survey
Background Many studies have demonstrated that obesity is closely linked with bone metabolism. A body shape index (ABSI) is a newly developed obesity indicator, which provides superior reflection of central obesity compared to body mass index (BMI) and waist circumference. Nevertheless, investigation of the association between ABSI and bone mineral density (BMD) remains limited. Thus, this study aimed to evaluate the correlation between ABSI and lumbar BMD among US adults. Methods We analyzed data of adults aged 20 years and older from 2011–2018 National Health and Nutrition Examination Survey. Weighted multiple regression analysis was conducted to assess the linear relationship between ABSI and lumbar BMD. Weighted smooth curve fitting and two-segment linear model were applied to explore the nonlinear association. Subgroup analysis stratified by age, gender, race, and BMI was performed. Results A total of 10991 subjects was enrolled in the study. In the fully adjusted model, the ABSI was negatively related to lumbar BMD (β = −0.007, 95% CI: −0.009, −0.005). The adverse correlation remained significant across all subgroups among stratified analysis. The saturation effect between ABSI and lumbar BMD was identified, with the turning point at the ABSI value of 0.08. Similar nonlinear trends were also observed in participants aged <40 years, males, Non-Hispanic White, BMI < 25 kg/m2, and BMI ≥ 30 kg/m2. Conclusion This study revealed a prominently negative correlation and saturation effect between ABSI and lumbar BMD in US adults. Our findings may provide valuable inspiration for further prevention and intervention of osteoporosis.
Spin glass-like and exchange bias behavior in the van der Waals Fe1/4-<i>δ</i>NbS2 single crystal
Manipulating different magnetic ground states in single-phase compounds is crucial for understanding and achieving a significant exchange bias effect. Here, Fe-vacancy doping into the perfect lattice of two-dimensional antiferromagnet Fe1/4NbS2 is achieved by growing Fe1/4-δNbS2 (δ = 0.01, 0.02, 0.05, and 0.09) single crystals. Coexistence of vacancy-induced ferromagnetic (FM) and antiferromagnetic (AFM) matrix phases is demonstrated in these compounds, with a low-temperature spin glass-like (SG-like) phase further identified. It is established that the magnetic ground state transitioned from strong AFM/weak SG to moderate AFM/SG and eventually to FM/SG with increasing Fe vacancies. Along with this transition, we observe a small exchange bias (EB) in δ = 0.01 and 0.02 (HEB = 0.074 and 0.13 T at 2 K), a giant one in δ = 0.05 (HEB = 1.04 T at 2 K), and a nearly negligible one in δ = 0.09. Our results prove the indispensable role of SG and AFM phases in engendering large EB effect in van der Waals two-dimensional magnets. This study can provide valuable insights into the exchange bias mechanism of two-dimensional bulk materials and offer efficient strategies for achieving substantial exchange bias fields.
Digital literacy impacts quality of life among older adults through hierarchical mediating mechanisms
Study on interfacial shear characteristics and progressive failure model of geotextile bags
Geotextile bag dams withstand the earth pressure of tailings in tailings reservoir by the shear stress on interface of geotextile bags. To improve the interfacial friction characteristics, pull-out tests were conducted on geotextile bags filled with fine tailings slurry containing various cement content, and the influences of cement content on the interfacial shear characteristics were explored. To describe the progressive failure of the interface, the theoretical analysis of interface pull-out behavior was performed. The results revealed that adding content cement into fine tailings slurry not only augmented the shear strength and residual strength ratio of the interface but also postponed interface softening. The optimal amount of cement was 3%, and the apparent friction angle which played a dominant role in interface strength was increased 17.4%, compared with no cement used. The elastic-plastic model and trilinear softening model were respectively improved to conform to the interfacial shear characteristics obtained in pull-out tests under low normal stress (< 60 kPa) and high normal stress (≥60 kPa). The interface shear stiffness of geotextile bag with the interfacial displacement within 20 mm and the dynamic compression modulus along the drawing direction were regarded as significant model parameters. The comparative analysis of shear stress-displacement curves, which were obtained from model calculating and test measuring, was carried out to verify the reliability and rationality of the model. The evolution patterns of the plastic zone, softening zone and residual zone of the interface were analyzed based on the model, and the warning values for interface failure were proposed. The development degree of interfacial plastic zone, softening zone and residual zone can be approximately calculated by quadratic polynomial of normalized pull-out force. The research results of this paper will provide reliable theoretical support for the design, construction and operation management of geotextile bag dams.
Significant enhancement of negative thermal expansion in LiYO2 induced by microstructure effect
The limited volume shrinkage rate poses a barrier to the application of negative thermal expansion (NTE) materials, and there are rare methods to significantly enhance NTE. Microstructure effect is an effective method to realize enhancement of NTE in bulk samples. However, there are a few reported materials exhibiting this effect. Herein, we achieved a significant enhancement of NTE in the phase-transition-type NTE material LiYO2. LiYO2 possesses a smaller unit cell volume in its high temperature phase than that in the low temperature phase, resulting in the intrinsic volume contraction (0.88%) before the phase transition completed. The volume contraction of the bulk sample reaches 3.66% from −100 to 50 °C, which is 4.16 times that of the powder sample. The results show that LiYO2 is sensitive to pressure, and the internal stress in the bulk sample facilitates the phase transition process. The anisotropy of LiYO2 and the pores in the bulk sample induce a microstructural effect. This work makes LiYO2 a promising material for NTE applications.
Data-driven diabetes mellitus prediction and management: a comparative evaluation of decision tree classifier and artificial neural network models along with statistical analysis
Enantioselective Spirocyclization of Pd‐Enolates and Isocyanates
AbstractAn enantioselective cyclization of Pd‐enolates and isocyanates to form spirocyclic γ‐lactams is reported. This reaction proceeds under mild reaction conditions and utilizes a novel Meldrum's acid derivative to achieve catalyst turnover, delivering enantioenriched products in up to 97% yield and 96% ee. Preliminary mechanistic investigations suggest that the reaction may proceed via the formation of higher‐order species.
Patients perceived challenges in seeking dental care in Komfo Anokye Teaching Hospital
Background Access to dental care services remains a global challenge, with millions encountering barriers that hinder their utilization, despite the recognized importance of oral health to overall well-being. The intricate relationship between oral health and general well-being highlights the severe impact of oral disorders on global economies and public health systems when access barriers exist. This study aimed to assess the perceived challenges in seeking dental care among patients at the Oral Health Directorate of Komfo Anokye Teaching Hospital. Methods This study employed a mixed methods approach, combining both quantitative and qualitative research methods for 130 respondents. With the quantitative approach: it was a cross-sectional design where structured questionnaires were administered to participants and data was analyzed using SPSS IBM version 23. The qualitative approach on the other hand, utilized semi-structured interviews to explore participants’ experiences, perspectives, and challenges related to accessing dental care. Data was analyzed using thematic analysis to identify key themes and patterns within the responses. The study had a response rate of 94.89%. Results Most respondents were females (56.2%) and aged 25–34 (26.9%). Approximately 55.4% had encountered barriers, with cost and lack of appointment times being major concerns. Regarding challenges at the dental clinics, lengthy waits (63.2%) and dental anxiety (77.0%) were the most common concerns. Gender and marital status were the only demographic characteristics which were statistically significantly associated with quality of care sought. Gender had a p-value of 0.00, indicating strong evidence of an association, while marital status had a p-value of 0.055, suggesting moderate evidence of an association. Marital status and education were found to be statistically significantly associated with perceived treatment-seeking behaviours, with p-values of 0.012 and 0.009 respectively. Postponement of dental care results in deteriorating oral health, higher expenses, and emotional strain for patients. The study identified long wait times, unclear communication, and financial barriers as key challenges. Patients proposed solutions including streamlined appointments, jargon-free explanations, and more affordable care options to improve dental experiences and accessibility. Conclusions Over half of respondents faced obstacles like cost and limited appointment availability. Patients also encountered challenges during dental visits, such as anxiety and long wait times. Demographics like gender, marital status, and education were linked to treatment-seeking behavior, suggesting potential disparities in access and utilization. Overall, the study highlights the complex interplay between socio-demographic factors, perceived barriers, patient experiences, and suggestions for enhancing dental care accessibility and quality.
Hysteretic responses of nanomechanical resonators based on crumpled few-layer graphene
The process of suspending two-dimensional materials over cavities etched in a substrate occasionally results in crumpled membranes. Their complicated morphologies feature an abundance of folds, creases, and wrinkles that make each crumpled membrane unique. Here, we prepare five nanomechanical resonators based on crumpled membranes of few-layer graphene and measure their static response and the resonant frequencies of their dynamic response. We tune both responses with a dc voltage applied between the membrane and an underlying gate electrode. Surprisingly, we find that all the resonators exhibit hysteretic responses as the gate voltage is increased and then decreased. Concomitant discontinuities in the static response and in the vibrational resonant frequencies indicate a sudden change in the shape and in the tensile strain of the membranes, accompanied by a change in elastic energy that we estimate. We find that the hystereses can be removed and regular responses can be restored by annealing the resonators.
In situ epoxidation of hybrid waste cooking oil and oleic acid via peracid mechanism
A novel spectral analysis-based grading system for gastrointestinal activity
Intestinal sounds, primarily generated by the movement of digested gas and liquids during peristalsis, are acoustic signals that provide valuable insights into intestinal functioning. Traditionally, doctors have relied on stethoscopes to assess the degree of gastrointestinal activity. Recent advancements in computer-aided technologies and electronic stethoscopes have enhanced the understanding and analysis of these sounds. Studies utilizing advanced techniques like deep learning and convolutional neural networks have shown promise in analyzing bowel sounds. Nevertheless, the reliance on personal judgment and the need for large labeled datasets limit the broader applicability of these methods. This study introduces an innovative, unsupervised grading system to objectively evaluate gastrointestinal motility by analyzing bowel sounds through spectral feature analysis. This system offers a practical alternative to traditional listening techniques or complex models. It computes an activity score for digital audio using a cost-effective numerical grading method to assist doctors in quantifying gastrointestinal motility. The method’s reliability, validated by Spearman’s rank correlation, confirms its accuracy in assessing activity levels and highlights its potential as a reliable and practical tool for supporting objective medical assessments of bowel activity.
Impact of anti-phase boundary on the magnetocaloric effect in geometrically frustrated epitaxial MnCr2O4
In epitaxially grown spinel thin films, the anti-phase boundaries (APBs) are formed due to cationic rearrangements within the spinels on the lattice-mismatched substrates. We demonstrate that such an APB formation could significantly influence the magnetocaloric effect (MCE) and suggest a model on how to avoid their formation and detrimental effects on MCE. We fabricate the geometrically frustrated epitaxial MnCr2O4 on SrTiO3 substrate with two different concentrations of APBs. The film with largely dense APB shows an entropy change, −ΔSM of ∼ 1.3 J/Kg-K, whereas the film with reduced APB shows a value of −ΔSM∼ 5.2 J/Kg-K for a change of field of 50 kOe. Furthermore, density functional theoretical calculations show that if there are more Jahn–Teller active A-site ions compared to B-site in an AB2O4 spinel, then such an APB formation is more probable. Hence, by creating a comparable fraction of Jahn–Teller active B-site cations, such an APB formation can be reduced. Moreover, avoiding the formation of APB and, thus, unwanted antiferromagnetic coupling at the boundaries could intrigue the future scientific community to design highly efficient magnetocaloric cooling devices using geometrically frustrated spinel systems.
Regional and age related variations in hepatitis A virus incidence in China 2004 to 2018: a descriptive epidemiological study
Frequency of ventricular arrhythmias in apparently healthy, large breed dogs during seven-day Holter monitoring
Continuous ambulatory electrocardiographic monitoring (Holter) is commonly used to diagnose and manage various cardiac arrhythmias in dogs. Despite its widespread use, data on the frequency of ventricular arrhythmias and its day-to-day variability in healthy, large-breed dogs without known predisposition to cardiomyopathy remains limited. This study assessed the frequency, complexity, and spontaneous day-to-day variation of ventricular arrhythmias in clinically healthy, large-breed dogs using seven-day Holter monitoring. Thirty-one, apparently healthy dogs without any history of systemic illness and normal physical examination findings underwent continuous 7-day Holter monitoring. Two dogs were excluded due to the occurrence of significant systemic disease soon after enrolment. The results from 29 dogs showed that most dogs (86%) had fewer than twenty ventricular premature complexes (VPCs) per 24-hour period, with significant day-to-day variation (up to 93%) in 4 dogs with over twenty VPCs. Complex ventricular arrhythmias, such as ventricular couplets, triplets, and ventricular tachycardia, were rare. No correlation was found between age and VPC frequency (p = 0.409) in this population of predominantly older dogs. These findings suggest that large-breed dogs without a predisposition to cardiomyopathies exhibit low arrhythmia frequencies with significant day-to-day variation in some dogs.
Influence of bias voltage on the performance of polarization-sensitive near-infrared photodiode based on dilute nitride GaNAs
Recent advances in ultrafast light polarization modulation and electrical control of polarization have increased the demand for polarization-sensitive photodetectors to enable polarization-based optical communication systems. The conduction electron population of dilute nitride GaNAs changes with excitation light polarization owing to the spin-dependent recombination of conduction electrons via the dynamic polarization of defect electron spins. However, polarization-sensitive photodetectors that utilize this property are limited to photoconductive devices with a long response time. In this study, we developed a polarization-sensitive near-infrared photodiode based on GaNAs. The influence of light power and bias voltage on the discrimination efficiency between circularly and linearly polarized light was investigated using coupled rate equation analysis for polarization-dependent photocurrent characteristics. At −2.0 V, where the discrimination efficiency reached 1%, the extraction time of the conduction electrons to the electrode was estimated to be 34 ps. This result suggests that the developed polarization-sensitive photodiode can operate at 10 GHz. The discrimination efficiency increased with light power because of the activated spin-selective capture of conduction electrons by spin-polarized defect states for circularly polarized light, whereas it decreased with increasing reverse bias voltage. This low performance originates from suppressed spin-selective capture, which is due to the combination of electric-field-induced spin relaxation and a decrease in the capture efficiency of conduction electrons. This study provides valuable insights into the influence of the bias voltage on the polarization-dependent photocurrent, which is a key challenge to the realization of practical polarization-sensitive photodiodes based on the spin-dependent recombination effect of conduction electrons.
Pivotal role of fibrous roots in drought tolerance of saffron (Crocus sativus L.) and mitigation of oxidative stress by penconazole
Comparing migration of Whinchats Saxicola rubetra from the non-breeding grounds in Liberia and Nigeria: Differences due to geography but otherwise very similar
Migrant birds in the Afro-Palearctic region are declining, so understanding general migration characteristics, such as site use, connectivity, and phenology is crucial for their conservation. We tracked 64 whinchats Saxicola rubetra, a declining Palearctic-breeding passerine, from non-breeding sites in Nigeria and Liberia, to Europe and back, in multiple years. We predicted differences, resulting from the geographical location of the two non-breeding sites, in location of respective breeding areas (migratory connectivity), number of non-breeding and stopover sites, migration distance and duration, degree of loop migration and phenology. But we predicted similarities, resulting from optimising migration behaviour, in migration leg distance duration, and stopover duration. Liberian tagged birds bred mainly in central and northern Europe, with Nigerian birds mainly in eastern Europe. Migratory spread was large resulting in range overlap and low connectivity. About 25% of whinchats used more than one sub-Saharan non-breeding site, their location dependent on geographic availability. Liberian birds had longer migrations in distance and duration, and more stopovers, but only Nigerian birds showed a statistically significant difference in longitude comparing spring and autumn migrations (i.e., a clear loop migration). Nigerian birds departed later than Liberian birds, independent of breeding latitude or migration distance, although latitude determined arrival time for breeding. Spring migration leg distance and stopover duration, and all leg durations, were similar for both populations; but Nigerian birds had longer duration stopovers and shorter distance migration legs in autumn. Whinchats were shown to have varied migration routes and characteristics, with a variable pace of migration that allows them between 50 and 75% of daylight hours to rest and forage, but with major stopover duration possibly being affected by site quality. One whinchat moved from sub-Saharan non-breeding site to northern European breeding site in 7 days, and 8% of complete migration durations were 14 days or less. This suggests whinchats are well adapted to the current variable geography and so may have the capacity to adapt to potential climate change across Europe and West Africa, although average quality and availability of stopover sites may be contributing to declines.
Improved performance of polycrystalline antiferromagnet/ferromagnet stack by nitrogen-assisted deposition
The deposition process of the IrMn3/Co70Fe30 bilayer of antiferromagnet/ferromagnet (AF/FM) type was modified by introducing a nitrogen additive in argon plasma during the magnetron sputtering of the Co70Fe30 layer. This slight modification significantly enhanced the exchange bias energy density and reduced coercivity of an AF/FM bilayer for the AF IrMn layer thickness ranging from 20 to 50 Å. Calculations indicate that the boost in exchange bias energy density and the reduction in coercivity can be attributed to the increased anisotropy energy of the AF layer, resulting in more effective pinning of the FM layer by AF grains. The increase in anisotropy is caused by the diffusion of nitrogen from the FM into the AF layer, as established by x-ray diffraction, neutron reflectometry, and x-ray magnetic circular dichroism. Our research allows us to improve magnetic characteristics of exchange-coupled FM/AF structures through minor modifications in the sputtering process and/or save up to 20% of the costly IrMn3 target by reducing the thickness of the AF layer.