High-spatial resolution ground-level ozone in Yunnan, China: A spatiotemporal estimation based on comparative analyses of machine learning models.

Monitoring ground-level ozone concentrations is a critical aspect of atmospheric environmental studies. Given the existing limitations of satellite data products, especially the lack of ground-level ozone characterization, and the discontinuity of ground observations, there is a pressing need for high-precision models to simulate ground-level ozone to assess surface ozone pollution. In this study, we have compared several widely utilized ensemble learning and deep learning methods for ground-level ozone simulation. Furthermore, we have thoroughly contrasted the temporal and spatial generalization performances of the ensemble learning and deep learning models. The 3-Dimensional Convolutional Neural Network (3-D CNN) model has emerged as the optimal choice for evaluating the daily maximum 8-h average ozone in Yunnan Province. The model has good performance: a spatial resolution of 0.05° × 0.05° and strong predictive power, as indicated by a Coefficient of Determination (R2) of 0.83 and a Root Mean Square Error (RMSE) of 12.54 µg/m³ in sample-based 5-fold cross-validation (CV). In the final stage of our study, we applied the 3-D CNN model to generate a comprehensive daily maximum 8-h average ozone dataset for Yunnan Province for the year 2021. This application has furnished us with a crucial high-resolution and highly accurate dataset for further in-depth studies on the issue of ozone pollution in Yunnan Province.

Interaction effect of screen time and sugar-sweetened beverages with depressive symptoms in adolescents: evidence from a large sample-based survey in China.

Excessive screen time and the consumption of sugar-sweetened beverages are found to be independent predictors of depressive symptoms. However, the potential interaction effect of screen time and sugar-sweetened beverages, that is, whether one exposure factor strengthens the association of another with depressive symptoms, remains unclear. A large-scale adolescent health surveillance survey was conducted in 27 schools in eight regions across China. A total of 22,868 students were recruited to complete an eligible questionnaire to provide details of their screen time and sugar-sweetened beverage consumption. Depressive symptoms were assessed using the Patient Health Questionnaire (PHQ-9). Multiplicative and additive interaction models were performed to estimate the interaction effects of screen time and sugar-sweetened beverages on depressive symptoms, and whether the relationship varied by age group was also examined. The multivariate logistic regression model showed that even if the confounding factors were controlled, screen time and sugar-sweetened beverages were still risk factors for depressive symptoms in adolescents. Interaction models indicated that screen time and sugar-sweetened beverages in combination were related to greater odds of depressive symptoms. Compared with late adolescents, early adolescents had a higher probability of depressive symptoms when exposed to the joint effects. Our study may hopefully deepen the understanding of the association between screen time and sugar-sweetened beverages and depressive symptoms. Future research should further explore how and why screen time and sugar-sweetened beverages affect individuals more profoundly in early adolescence than in late adolescence and how to mitigate this.

Chromosome-level genome assembly and population genomic analysis provide novel insights into the immunity and evolution of Sogatella furcifera.

Sogatella furcifera is a destructive agricultural pest causing large threats to rice production in China and Southeast Asian countries. Despite recent breakthroughs in long-read sequencing, high quality genomic data are very limited in S. furcifera. In present study, a chromosome-level assembly of the S. furcifera genome was completed (0.64 GB), comprising 15 chromosomes covered 95.04% of the estimated genome size, along with other 624 small scaffolds making up the remaining 4.96% of the genome of S. furcifera. A total of 24,669 protein-coding genes, 1211 long noncoding RNA and 7595 circular RNA transcripts were predicted in this study. Comparative genomic analysis revealed rapidly evolved genes were associated with multiple immune-related pathways in S. furcifera. Genome resequencing of 44 individuals from 12 geographic populations revealed frequent gene flow among populations. The systemic genomic analysis will provide more insights into the understanding of the immunity and evolutionary adaptation of S. furcifera.

Metal-Free Activation of Molecular Oxygen by 9-Fluorenone-Based Porous Organic Polymers for Selective Aerobic Oxidation.

Oxygen activation is a critical step in heterogeneous oxidative processes, particularly in catalytic, electrolytic, and pharmaceutical applications. Among the various catalysts available for photocatalytic O2 activation, homogeneous aryl ketones are at the forefront. To avoid the degradation and deactivation of aryl ketones, 9-fluorenone-based porous organic polymers were designed and regulated by doping them with co-monomers. The obtained heterogeneous photocatalyst showed good performance in O2 activation, and its performance was better than that of homogeneous 9-fluorenone. The obtained heterogeneous photocatalyst showed good reusability. We believe that the presented method and findings represent an important step toward designing catalysts tailored for specific tasks.

A pilot study on the use of a novel digital real-time evaluation system in undergraduate preclinical training of tooth preparation in fixed prosthodontics.

INTRODUCTION: In the light of the digital teaching, it is necessary that the effectiveness of a new digital real-time evaluation system in the preclinical training of tooth preparation be evaluated. MATERIALS AND METHODS: Forty undergraduate dental students of the fourth year were randomly divided into the control group and the experimental group to complete the training task of tooth preparation for porcelain fused to metal (PFM) crown restoring the upper right central incisor. The control students received conventional training with instructor's guidance. The experimental students received training with the digital system without instructor's guidance. Every student exercised preparation in two resin incisors in 3 h training by respective training methods. A third incisor was prepared on a dental model in the simulated head phantom by each student as the test on the next day. All students' tooth preparations were scored by the same two experienced experts. The experimental students were asked to answer a questionnaire regarding their attitudes and opinions on the digital evaluation system in preclinical training. RESULTS: There was no significant difference between the scores of the experimental group and the control group (p > .05). The students of two groups obtained the similar scores in the test (p > .05). Most of the students were supportive of the application of digital training system in the preclinical tooth preparation training course. CONCLUSIONS: The digital real-time evaluation system could provide effective training effects for the dental undergraduate students in the preclinical training of tooth preparation in fixed prosthodontics.

E_{8} Spectra of Quasi-One-Dimensional Antiferromagnet BaCo_{2}V_{2}O_{8} under Transverse Field.

We report ^{51}V NMR and inelastic neutron scattering (INS) measurements on a quasi-1D antiferromagnet BaCo_{2}V_{2}O_{8} under transverse field along the [010] direction. The scaling behavior of the spin-lattice relaxation rate above the Néel temperatures unveils a 1D quantum critical point (QCP) at H_{c}^{1D}≈4.7 T, which is masked by the 3D magnetic order. With the aid of accurate analytical analysis and numerical calculations, we show that the zone center INS spectrum at H_{c}^{1D} is precisely described by the pattern of the 1D quantum Ising model in a magnetic field, a class of universality described in terms of the exceptional E_{8} Lie algebra. These excitations are nondiffusive over a certain field range when the system is away from the 1D QCP. Our results provide an unambiguous experimental realization of the massive E_{8} phase in the compound, and open a new experimental route for exploring the dynamics of quantum integrable systems as well as physics beyond integrability.

Quantum Criticality of the Ising-like Screw Chain Antiferromagnet SrCo_{2}V_{2}O_{8} in a Transverse Magnetic Field.

The quantum criticality of an Ising-like screw chain antiferromagnet SrCo_{2}V_{2}O_{8}, with a transverse magnetic field applied along the crystalline a axis, is investigated by ultralow temperature NMR measurements. The Néel temperature is rapidly and continuously suppressed by the field, giving rise to a quantum critical point (QCP) at H_{C_{1}}≈7.03 T. Surprisingly, a second QCP at H_{C_{2}}≈7.7 T featured with gapless excitations is resolved from both the double-peak structure of the field-dependent spin-lattice relaxation rate 1/^{51}T_{1} at low temperatures and the weakly temperature-dependent 1/^{51}T_{1} at this field. Our data, combined with numerical calculations, suggest that the induced effective staggered transverse field significantly lowers the critical fields, and leads to an exposed QCP at H_{C_{2}}, which belongs to the one-dimensional transverse-field Ising universality.

PLGA film/Titanium nanotubues as a sustained growth factor releasing system for dental implants.

Ti-based implants sometimes fail to integrate with surrounding bone tissue due to insufficiency of new bone formation and surface bonding. To overcome this problem, this research focused on establishing a sustained bone growth factor delivery system by applying anodized TiO2 nanotube arrays and PLGA film on the titanium implant surface. TiO2 nanotube arrays were made by anodic oxidation method, and were then filled with rhBMP2 by vacuum freeze-drying. Next, PLGA was deposition on the surface of this material. The designed system was characterized, pharmacokinetic release rate of rhBMP2 was determined. Adhesion, proliferation, and differentiation activity of osteoblasts cultured on the new surfaces and traditional titanium surfaced were compared. SEM showed that a surface of TiO2 nanotube arrays were successfully generated. PLGA membranes of 50 nm, 250 nm, 800 nm thickness were successfully deposited on the surfaces of TiO2 nanotube layers by using 1%, 3%, 10% PLGA solutions. PLGA film of 250 nm thickness showed ideally controlled release of rhBMP2, lasting for 4 weeks. Furthermore, 250 nm thickness PLGA film improved osteoblast adhesion, proliferation, and levels of alkaline phosphatase. In conclusion, the PLGA film / TiO2 nanotube growth factor delivery system can effectively sustain the release of rhBMP-2, and promote proliferation and differentiation of MC3T3-E1 osteoblasts.

Gapless Spin Excitations in the Field-Induced Quantum Spin Liquid Phase of α-RuCl_{3}.

α-RuCl_{3} is a leading candidate material for the observation of physics related to the Kitaev quantum spin liquid (QSL). By combined susceptibility, specific-heat, and nuclear-magnetic-resonance measurements, we demonstrate that α-RuCl_{3} undergoes a quantum phase transition to a QSL in a magnetic field of 7.5 T applied in the ab plane. We show further that this high-field QSL phase has gapless spin excitations over a field range up to 16 T. This highly unconventional result, unknown in either Heisenberg or Kitaev magnets, offers insight essential to establishing the physics of α-RuCl_{3}.

Pressure Induced Stripe-Order Antiferromagnetism and First-Order Phase Transition in FeSe.

To elucidate the magnetic structure and the origin of the nematicity in FeSe, we perform a high-pressure ^{77}Se NMR study on FeSe single crystals. We find a suppression of the structural transition temperature with pressure up to about 2 GPa from the anisotropy of the Knight shift. Above 2 GPa, a stripe-order antiferromagnetism that breaks the spatial fourfold rotational symmetry is determined by the NMR spectra under different field orientations and with temperatures down to 50 mK. The magnetic phase transition is revealed to be first-order type, implying the existence of a concomitant structural transition via a spin-lattice coupling. Stripe-type spin fluctuations are observed at high temperatures, and remain strong with pressure. These results provide clear evidence for strong coupling between nematicity and magnetism in FeSe, and therefore support a universal scenario of magnetic driven nematicity in iron-based superconductors.

Reciprocal interaction between dental alloy biocorrosion and Streptococcus mutans virulent gene expression.

Corrosion of dental alloys is a major concern in dental restorations. Streptococcus mutans reduces the pH in oral cavity and induces demineralization of the enamel as well as corrosion of restorative dental materials. The rough surfaces of dental alloys induced by corrosion enhance the subsequent accumulation of plaque. In this study, the corrosion process of nickel-chromium (Ni-Cr) and cobalt-chromium (Co-Cr) alloys in a nutrient-rich medium containing S. mutans was studied using inductively coupled plasma atomic emission spectrometry (ICP-AES), X-ray photoelectron spectroscopy (XPS) and electrochemical corrosion test. Our results showed that the release of Ni and Co ions increased, particularly after incubation for 3 days. The electrochemical corrosion results showed a significant decrease in the corrosion resistance (Rp) value after the alloys were immersed in the media containing S. mutans for 3 days. Correspondingly, XPS revealed a reduction in the relative dominance of Ni, Co, and Cr in the surface oxides after the alloys were immersed in the S. mutans culture. After removal of the biofilm, the pre-corroded alloys were re-incubated in S. mutans medium, and the expressions of genes associated with the adhesion and acidogenesis of S. mutans, including gtfBCD, gbpB, fif and ldh, were evaluated by detecting the mRNA levels using real-time reverse transcription polymerase chain reaction (RT-PCR). We found that the gtfBCD, gbpB, ftf and Idh expression of S. mutans were noticeably increased after incubation with pre-corroded alloys for 24 h. This study demonstrated that S. mutans enhanced the corrosion behavior of the dental alloys, on the other hand, the presence of corroded alloy surfaces up-regulated the virulent gene expression in S. mutans. Compared with smooth surfaces, the rough corroded surfaces of dental alloys accelerated the bacteria-adhesion and corrosion process by changing the virulence gene expression of S. mutans.

Effects of lipopolysaccharides on the corrosion behavior of Ni-Cr and Co-Cr alloys.

STATEMENT OF PROBLEM: Lipopolysaccharides (LPS) are constituents of gingival crevicular fluid and may affect the base metal alloys used in metal ceramic crowns. The role of LPS in base metal alloys is currently unknown. PURPOSE: The purpose of this in vitro study was to evaluate the effects of gram-negative bacterial LPS on the electrochemical behavior of Ni-Cr and Co-Cr alloys. MATERIAL AND METHODS: Alloy specimens were divided into 4 groups according to Escherichia coli LPS concentration (0, 0.15, 15, and 150 µg/mL) in acidic saliva (pH 5). Open circuit potential (OCP) and potentiodynamic polarization behavior were examined using a computer-controlled potentiostat. Metal ions released from the 2 alloys were measured by immersion in LPS-free solution and 150 µg/mL LPS solution and analyzed by inductively coupled plasma atomic emission spectrometry (ICP-AES). Data were evaluated using 1-way ANOVA (α=.05). RESULTS: Compared with control groups, medium LPS concentration (15 µg/mL) accelerated Ni-Cr alloy corrosion (P<.05), whereas high LPS concentration (150 µg/mL) accelerated Co-Cr alloy corrosion (P<.05), as determined by OCP, corrosion current density, and polarization resistance parameters. After immersion in high LPS concentrations (150 µg/mL), a slight increase in Ni ion release (P >.05) was observed for the Ni-Cr alloy, while a more significant Co ion release (P<.05) was observed for the Co-Cr alloy. CONCLUSIONS: LPS negatively affected the electrochemical behavior of both the Ni-Cr and Co-Cr alloys.

Electrochemical impedance investigation of Ni-free Co-Cr-Mo and Co-Cr-Mo-Ni dental casting alloy for partial removable dental prosthesis frameworks.

STATEMENT OF PROBLEM: The pH level of the oral environment influences corrosion in dental materials. Corrosion behaviors of Co-Cr-Mo and Co-Cr-Mo-Ni alloys in different pH environments remain undetermined. PURPOSE: The purpose of this in vitro study was to evaluate the surface properties and corrosion behaviors of Co-Cr-Mo and Co-Cr-Mo-Ni dental casting alloys in artificial saliva at pH values of 5.0 and 2.5. MATERIAL AND METHODS: Fifty specimens were divided into 2 groups according to the alloy composition. The surface compositions, hardness values, and microstructures of the alloys were measured before immersion in artificial saliva. The corrosion behaviors of the specimens in artificial saliva at pH values of 5.0 and 2.5 were studied using electrochemical impedance spectroscopy (EIS). The microstructures were examined again after a 7-day immersion test. Data were analyzed by a 1-way analysis of variance (ANOVA) test (α=.05). RESULTS: As expected, the relative levels of Co and Cr of the surface composition were higher in the Co-Cr-Mo alloy. The Co-Cr-Mo alloy had statistically higher surface hardness than the Co-Cr-Mo-Ni alloy (P<.05). In the pH 2.5 environment, both of the alloys showed decreased corrosion resistance (P<.05). The microstructure of the Co-Cr-Mo-Ni alloy corroded more than that of the Co-Cr-Mo alloy in the pH 2.5 environment. The oxide-layer corrosion resistance of the Co-Cr-Mo alloy was better than that of the Co-Cr-Mo-Ni alloy in Fusayama artificial saliva solutions at pH values of both 5.0 and 2.5 (P<.05). CONCLUSIONS: The corrosion resistance of the Co-Cr-Mo alloy was better in the oral environment, especially at a low pH value.

Production of Diethyl Terephthalate from Biomass-Derived Muconic Acid.

We report a cascade synthetic route to directly obtain diethyl terephthalate, a replacement for terephthalic acid, from biomass-derived muconic acid, ethanol, and ethylene. The process involves two steps: First, a substituted cyclohexene system is built through esterification and Diels-Alder reaction; then, a dehydrogenation reaction provides diethyl terephthalate. The key esterification reaction leads to improved solubility and modulates the electronic properties of muconic acid, thus promoting the Diels-Alder reaction with ethylene. With silicotungstic acid as the catalyst, nearly 100% conversion of muconic acid was achieved, and the cycloadducts were formed with more than 99.0% selectivity. The palladium-catalyzed dehydrogenation reaction preferentially occurs under neutral or mildly basic conditions. The total yield of diethyl terephthalate reached 80.6% based on the amount of muconic acid used in the two-step synthetic process.

Structural and Magnetic Phase Transitions near Optimal Superconductivity in BaFe2(As(1-x)Px)2.

We use nuclear magnetic resonance (NMR), high-resolution x-ray, and neutron scattering studies to study structural and magnetic phase transitions in phosphorus-doped BaFe2(As(1-x)P(x)2. Previous transport, NMR, specific heat, and magnetic penetration depth measurements have provided compelling evidence for the presence of a quantum critical point (QCP) near optimal superconductivity at x=0.3. However, we show that the tetragonal-to-orthorhombic structural (T{s}) and paramagnetic to antiferromagnetic (AF, TN) transitions in BaFe2(As(1-x)Px)2 are always coupled and approach T{N}≈T{s}≥T{c} (≈29 K) for x=0.29 before vanishing abruptly for x≥0.3. These results suggest that AF order in BaFe_{2}(As(1-x)Px)2 disappears in a weakly first-order fashion near optimal superconductivity, much like the electron-doped iron pnictides with an avoided QCP.

The effect of Ti anodized nano-foveolae structure on preosteoblast growth and osteogenic gene expression.

The TiO2 nanotubes by anodization have been extensively studied for medical implant and orthopedic applications because of enhancing bone development. In the present study, a new nano-foveolae structure verified by SEM and AFM was prepared by simulating the nanotubes exfoliation from anodized Ti. MC3T3-E1 preosteoblasts were used to investigate the effects of new nanoscale surface on cell spreading, proliferation, and osteogenic gene expression. The new nano-foveolae structure supported preosteoblast better spreading, more filopodiaes shown by SEM (4 h), and lower proliferation (72 h) than the smooth Ti. By two weeks, the new nanoscale surface induced higher expression of osteogenic markers alkaline phosphatase (ALP), osteopontin (OPN), osteocalcin (OCN), and collagen I (COL I) with real-time RT-PCR compared to the control group. The results of this study suggest that the new nano-foveolae structure provides a favorable surface for functions of bone cells.

Physical activity patterns and cognitive function in elderly women: a cross-sectional study from NHANES 2011-2014.

Background: Amid the backdrop of global aging, the increasing prevalence of cognitive decline among the elderly, particularly within the female demographic, represents a considerable public health concern. Physical activity (PA) is recognized as an effective non-pharmacological intervention for mitigating cognitive decline in older adults. However, the relationship between different PA patterns and cognitive function (CF) in elderly women remains unclear. Methods: This study utilized data from National Health and Nutrition Examination Survey (NHANES) 2011-2014 to investigate the relationships between PA, PA patterns [inactive, Weekend Warrior (WW), and Regular Exercise (RE)], and PA intensity with CF in elderly women. Multivariate regression analysis served as the primary analytical method. Results: There was a significant positive correlation between PA and CF among elderly women (ß-PA: 0.003, 95% CI: 0.000-0.006, P = 0.03143). Additionally, WW and RE activity patterns were associated with markedly better cognitive performance compared to the inactive group (ß-WW: 0.451, 95% CI: 0.216-0.685, P = 0.00017; ß-RE: 0.153, 95% CI: 0.085-0.221, P = 0.00001). Furthermore, our results indicate a progressive increase in CF with increasing PA intensity (ß-MPA- dominated: 0.16, 95% CI: 0.02-0.09, P = 0.0208; ß-VPA-dominated: 0.21, 95% CI: 0.09-0.34, P = 0.0011; ß-Total VPA: 0.31, 95% CI: -0.01-0.63, P = 0.0566). Conclusion: Our study confirms a positive association between PA and CF in elderly women, with even intermittent but intensive PA models like WW being correlated with improved CF. These findings underscore the significant role that varying intensities and patterns of PA play in promoting cognitive health among older age groups, highlighting the need for adaptable PA strategies in public health initiatives targeting this population.

Unraveling metabolic characteristics and clinical implications in gastric cancer through single-cell resolution analysis.

Background: Gastric cancer is a highly prevalent malignant neoplasm. Metabolic reprogramming is intricately linked to both tumorigenesis and cancer immune evasion. The advent of single-cell RNA sequencing technology provides a novel perspective for evaluating cellular metabolism. This study aims to comprehensively investigate the metabolic pathways of various cell types in tumor and normal samples at high resolution and delve into the intricate regulatory mechanisms governing the metabolic activity of malignant cells in gastric cancer. Methods: Utilizing single-cell RNA sequencing data from gastric cancer, we constructed metabolic landscape maps for different cell types in tumor and normal samples. Employing unsupervised clustering, we categorized malignant cells in tumor samples into high and low metabolic subclusters and further explored the characteristics of these subclusters. Results: Our research findings indicate that epithelial cells in tumor samples exhibit significantly higher activity in most KEGG metabolic pathways compared to other cell types. Unsupervised clustering, based on the scores of metabolic pathways, classified malignant cells into high and low metabolic subclusters. In the high metabolic subcluster, it demonstrated the potential to induce a stronger immune response, correlating with a relatively favorable prognosis. In the low metabolic subcluster, a subset of cells resembling cancer stem cells (CSCs) was identified, and its prognosis was less favorable. Furthermore, a set of risk genes associated with this subcluster was discovered. Conclusion: This study reveals the intricate regulatory mechanisms governing the metabolic activity of malignant cells in gastric cancer, offering new perspectives for improving prognosis and treatment strategies.

Effects of social-ecological risk factors and resilience on the relationship between metabolic metrics and mental health among young adults.

The correlation between metabolic metrics and mental health remains underexplored, with few in-depth studies examining whether this association exists among college students and whether it might be moderated by socio-ecological risk factors (SERFs) and mediated by resilience. A follow-up study design investigated the association between baseline metabolic metrics, SERFs and resilience and mental health. A multivariable linear regression model using the PROCESS method established the relationship of SERFs, resilience and metabolic metrics with mental health. Participants were 794 adolescents (mean age: 18.64 [±0.90] years). In multivariable linear regression, the high-level SERFs (ß = 0.124), resilience (ß = -0.042), LCI (ß = 0.072), and RFM (ß = 0.145) were associated with higher depression symptoms, while CVH (ß = 0.602), TyG (ß = 0.295), TyG-BMI (ß = 0.004), and RC (ß = -0.041) were not. An association was also observed between SERFs, resilience, RFM and anxiety. Resilience mediated the relationship between metabolic metrics and depression and anxiety, and SERFs moderated this relationship, demonstrating the relationship between resilience, metabolic metrics, SERFs and mental health. By revealing the potential sociological mechanism underlying the relationship between metabolic metrics and adolescents' mental health, this study provides a theoretical basis for further exploration of the biological foundations of mental health.

Simultaneous optimization of spin fluctuations and superconductivity under pressure in an iron-based superconductor.

We present a high-pressure NMR study of the overdoped iron pnictide superconductor NaFe0.94Co0.06As. The low-energy antiferromagnetic spin fluctuations in the normal state, manifest as the Curie-Weiss upturn in the spin-lattice relaxation rate 1/(75)T1T, first increase strongly with pressure but fall again at P>Popt=2.2 GPa. Neither long-ranged magnetic order nor a structural phase transition is encountered up to 2.5 GPa. The superconducting transition temperature Tc shows a pressure dependence identical to the spin fluctuations. Our observations demonstrate that magnetic correlations and superconductivity are optimized simultaneously as a function of the electronic structure, thereby supporting very strongly a magnetic origin of superconductivity.