Epoxy Resins with Controllable "Thermally Conductive-Self-Healing" Synergies: a New Material to Meet the Needs of Flexible Electronic Devices

With the popularization of 5G technology and artificial intelligence, thermally conductive epoxies with self-healing ability will be widely used in flexible electronic materials. Although many compounds containing both performances have been synthesized, there is little systematic theory to explain this coordination mechanism. In this paper, alkyl chains of different lengths were introduced to epoxies for discussing the thermally conductive, the self-healing performance, and the synergistic effect. A series of electronic-grade biphenyl epoxies (4,4'-bis(oxiran-2-ylmethoxy)-1,1'-biphenyl (1), 4,4'-bis(2-(oxiran-2-yl)ethoxy)-1,1'-biphenyl (2), 4,4'-bis(3-(oxiran-2-yl)propoxy)-1,1'-biphenyl (3), and 4,4'-bis(4-(oxiran-2-yl)butoxy)-1,1'-biphenyl (4) were synthesized and characterized. Furthermore, they were cured with decanedioic acid to produce polymers. Results showed that alkyl chains can both affect the two properties, and the epoxies suitable for specific application scenarios can be prepared by adjusting the length of alkyl chains. In terms of thermal conductivity, compound 1 was a most promising material. However, compound 4 was expected to be utilized in flexible electronic devices because of its acceptable thermal conductivity, self-healing ability, transparency, and flexibility.

Dual-channel mechano-phosphorescence: a combined locking effect with twisted molecular structures and robust interactions

Organic mechanoluminescence materials, featuring dual emission and ultralong phosphorescence characteristics, exhibit significant potential for applications in real-time stress sensing, pressure-sensitive lighting, advanced security marking techniques, and material breakage monitoring. However, due to immature molecular design strategies and unclear luminescence mechanisms, these materials remain rarely reported. In this study, we propose a valuable molecular design strategy to achieve dual-channel mechano-phosphorescence. By introducing the arylphosphine oxide group into a highly twisted molecular framework, enhanced intra- and intermolecular interactions could be achieved within rigid structures, leading to dual-channel mechanoluminescence with greatly promoted ultralong phosphorescence. Further investigations reveal the substantial boosting effect of intra- and intermolecular interactions on mechanoluminescence and ultralong phosphorescence properties by locking the highly twisted molecular skeleton. This work provides a concise and guiding route to develop novel smart responsive luminescence materials for widespread applications in material science.

UiO-66/AgNPs Coating for Dental Implants in Preventing Bacterial Infections

Titanium (Ti)-based biomaterials lack inherent antimicrobial activities, and the dental plaque formed on the implant surface is one of the main risk factors for implant infections. Construction of an antibacterial surface can effectively prevent implant infections and enhance implant success. Silver nanoparticles (AgNPs) exhibit broad antibacterial activity and a low tendency to induce drug resistance, but AgNPs easily self-aggregate in the aqueous environment, which significantly impairs their antibacterial activity. In this study, UiO-66/AgNP (U/A) nanocomposite was prepared, where zirconium metal-organic frameworks (UiO-66) were employed as the confinement matrix to control the particle size and prevent aggregation of AgNPs. The bactericidal activity of U/A against methicillin-resistant Staphylococcus aureus and Escherichia coli increased nearly 75.51 and 484.50 times compared with individually synthesized Ag. The antibacterial mechanism can be attributed to the enhanced membrane rupture caused by the ultrafine AgNPs on UiO-66, leading to protein leakage and generation of intracellular reactive oxygen species. Then, U/A was loaded onto Ti substrates (Ti-U/A) by using self-assembly deposition methods to construct an antibacterial surface coating. Ti-U/A exhibited excellent antibacterial activities and desired biocompatibility both in vitro and in vivo. The U/A nanocomposite coating technique is thus expected to be used as a promising surface modification strategy for Ti-based dental implants for preventing dental implant infections.

Dynamic Ultra-long Room Temperature Phosphorescence Enabled by Amorphous Molecular "Triplet Exciton Pump" for Encryption with Temporospatial Resolution

Organic ultra-long room-temperature phosphorescence (RTP) materials in the amorphous state have attracted widespread attention due to their simple preparation and flexibility to adopt various forms in sensors, bioimaging, and encryption applications. However, the amorphous molecular host for the host-guest RTP systems is highly demanded but limited. Here, a universal molecular host (DPOBP-Br) has been designed by integration of an amorphous moiety of diphenylphosphine oxide (DPO) and an intersystem crossing (ISC) group of 4-bromo-benzophenone (BP-Br). Various commercial fluorescence dyes were doped into the tight and transparent DPOBP-Br film, respectively, resulting in amorphous host-guest systems with ultra-long RTP colors from green to red. It was found that DPOBP-Br acted as a universal "triplet exciton pump" for promoting the generation of triplet excitons in the guest, through energy transfer processes and external heavy-atom effect based on DPOBP-Br. Interestingly, dynamic RTP was achieved by controlling residual oxygen concentration in the amorphous matrix by UV irradiation. Therefore, multi-dimensional anti-counterfeiting coatings were realized even on curved surfaces, simultaneously exhibiting spatial and 2D-time dependence. This work provides a strategy to design new amorphous molecular hosts for RTP systems and demonstrates the advanced information encryption with tempo-spatial resolution based on the dynamic ultra-long RTP of an amorphous system.

The molecular mechanism of naringin improving endometrial receptivity of OHSS rats

Controlling ovarian hyperstimulation syndrome (OHSS) in the controlled ovarian hyperstimulation treatment is necessary to increase the implantation success rate. This study aimed to explore the effect of naringin on the endometrial receptivity of OHSS rats. Female rats were randomly assigned to six groups: Blank, model, low-dose naringin (100 mg/kg/day), medium-dose naringin (200 mg/kg/day), high-dose naringin (400 mg/kg/day), and positive (0.18 mg/kg/day estradiol valerate) groups. Except for the blank group, rats established the OHSS model on Day 7, and their treatments were from Day 0 to 14, separately. Hematoxylin and eosin, immunohistochemical, and scanning electron microscopy were performed to detect the naringin effects on the endometrial receptivity of the OHSS model. Next, circRNAs transcriptome analysis was performed to screen circRNAs. Western blot analysis and real-time quantitative PCR were used to verify it. Our study showed that naringin treatments increased embryo number, endometrial thickness, pinopodes number, and Ki67 expression in the OHSS rats. Moreover, the result of circRNAs transcriptome sequencing showed that naringin significantly inhibited the rnocirc_008140 expression in the OHSS rats and significantly inhibited the changes of 28 gene ontology terms and three Kyoto Encyclopedia of Genes and Genomes pathways which were induced by OHSS. Abcc4 and Rps6ka5 genes were the enriched genes of those pathways. Finally, 24 miRNA target genes of rnocirc_008140 were predicted. Our study showed that naringin significantly improved the endometrial receptivity of OHSS rats to increase the embryo implantation success by reducing rnocirc_008140-adsorbed miRNAs to regulate Abcc4 and Rps6ka5 expression.

Achieving Stable and Switchable Ultralong Room-Temperature Phosphorescence from Polymer-Based Luminescent Materials with Three-Dimensional Covalent Networks for Light-Manipulated Anticounterfeiting

Developing polymer-based organic afterglow materials with switchable ultralong organic phosphorescence (UOP) that are insensitive to moisture remains challenging. Herein, two organic luminogens, BBCC and BBCS, were synthesized by attaching 7H-benzo[c]carbazole (BBC) to benzophenone and diphenyl sulfone. These two emitters were employed as guest molecules and doped into epoxy polymers (EPs), which were constructed by in situ polymerization to achieve polymer materials BBCC-EP and BBCS-EP. It was found that BBCC-EP and BBCS-EP films exhibited significant photoactivated UOP properties. After light irradiation, they could produce a conspicuous organic afterglow with phosphorescence quantum yields and lifetimes up to 5.35% and 1.91 s, respectively. Meanwhile, BBCS-EP also presented photochromic characteristics. Upon thermal annealing, the UOP could be turned off, and the polymer films recovered to their pristine state, showing switchable organic afterglow. In addition, BBCC-EP and BBCS-EP displayed excellent water resistance and still produced obvious UOP after soaking in water for 4 weeks. Inspired by the unique photoactivated UOP and photochromic properties, BBCC and BBCS in the mixtures of diglycidyl ether of bisphenol A (DGEBA) and 1,3-propanediamine were employed as security inks for light-controlled multilevel anticounterfeiting. This work may provide helpful guidance for developing photostimuli-responsive polymer-based organic afterglow materials, especially those with stable UOP under ambient conditions.

Synergetic Conformational Regulations in Ground and Excited States for Realizing Stimulus-Responsive and Wide-Tuning Room-Temperature Phosphorescence

Understanding the changes of molecular conformations is crucial for realizing multiple emissive triplet states in room-temperature phosphorescence (RTP) materials. In this work, we report two molecules, 4,4'-dimethylbenzil (DMBZ) and 4,4'-di-tert-butylbenzil (DBBZ) with conformation-dependent luminescence, and demonstrate that stimulus-responsive and wide-tuning RTP emissions can be realized via synergetic conformational regulations in ground and excited states. Due to conformational changes, DMBZ and DBBZ show abundant RTP variations upon external stimuli, including light, force, heat, and fumigation. Notably, DBBZ exhibits multiple conformational changes in both ground and excited states, which endow DBBZ with multiple emissive states and unique stimulus-responsive behaviors. DBBZ presents multiple phase transitions between the supercooled liquid state and different solid states accompanied by different phosphorescence transitions, in which the excited-state conformations are effectively regulated. Moreover, wide-range RTP regulations (between cyan, green, and yellow) are realized in both single component and host-guest systems of DBBZ, showing potential applications in temperature sensing, multicolor dynamic displays, and information encryption. These results may provide new visions for understanding the complicated conformational changes in the aggregated state, as well as unique insights into the relationship between molecular conformations, RTP emissions, and stimulus responsiveness.

Excellent Energy Storage Performance in Epoxy Resin Dielectric Polymer Films by a Facile Hot-Pressing Method

Epoxy resin (EP), as a kind of dielectric polymer, exhibits the advantages of low-curing shrinkage, high-insulating properties, and good thermal/chemical stability, which is widely used in electronic and electrical industry. However, the complicated preparation process of EP has limited their practical applications for energy storage. In this manuscript, bisphenol F epoxy resin (EPF) was successfully fabricated into polymer films with a thickness of 10~15 μm by a facile hot-pressing method. It was found that the curing degree of EPF was significantly affected by changing the ratio of EP monomer/curing agent, which led to the improvement in breakdown strength and energy storage performance. In particular, a high discharged energy density (U_d) of 6.5 J·cm^-3 and efficiency (η) of 86% under an electric field of 600 MV·m^-1 were obtained for the EPF film with an EP monomer/curing agent ratio of 1:1.5 by hot pressing at 130 °C, which indicates that the hot-pressing method could be facilely employed to produce high-quality EP films with excellent energy storage performance for pulse power capacitors.

The association of serum testosterone with dyslipidemia is mediated by obesity: the Henan Rural Cohort Study

BACKGROUND AND AIMS

This study aimed to evaluate the relationships of serum testosterone with dyslipidemia and blood lipid levels and test whether obesity mediated these associations by gender in Chinese rural population.

METHODS AND RESULTS

A total of 6150 subjects were finally analyzed in this study. Serum testosterone for each subject was detected by liquid chromatography equipped with tandem mass spectrometry. Logistic regression and linear regression were employed to evaluate the associations of serum testosterone with the prevalence of dyslipidemia and blood lipid levels. Mediation analysis was conducted to identify the mediation effects of obesity on the relationship between serum testosterone and dyslipidemia. After adjusting for multiple confounders, per unit change in serum ln-testosterone levels was associated with a decreased prevalent dyslipidemia in men (odds ratio (OR): 0.785, 95% confidence interval (CI) (0.708, 0.871)). Males with the levels of serum testosterone in the third or fourth quartiles had a 49.4% (OR: 0.506, 95% CI 0.398, 0.644) or 67.1% (OR: 0.329, 95% CI 0.253, 0.428) significantly lower odds of prevalence of dyslipidemia. In addition, a onefold increase in ln-testosterone was related to a 0.043 mmol/L (95% CI 0.028, 0.059) increase in high-density lipoprotein cholesterol (HDL-C) in men. Results of the mediation analysis suggested that obesity played a partial role in the association of testosterone with dyslipidemia in men.

CONCLUSIONS

These findings suggested that serum testosterone levels were negatively associated with lipid levels and prevalent dyslipidemia, and obesity mediated the effects of serum testosterone on dyslipidemia in men, implying that obesity prevention should be highlighted to decrease the prevalence of dyslipidemia related to changes in testosterone levels.

Predictors of postoperative biochemical remission in lower Knosp grade growth hormone-secreting pituitary adenomas: a large single center study

PURPOSE

Growth hormone-secreting pituitary adenomas (GH-PAs) with a low Knosp grade are typically associated with a good postoperative biochemical remission (BR) rate. However, a proportion of patients do not achieve remission. In this study, we aimed to investigate predictive factors of postoperative remission for lower Knosp GH-PAs.

METHODS

In this retrospective study, we enrolled 140 patients who were diagnosed with lower Knosp (0-2) GH-PAs and received trans-sphenoidal surgery between December 2016 and June 2021 from the largest pituitary tumor surgery center in southern China. The univariate, binary Logistic regression, and receiver operating characteristic curve (ROC) analyses were employed to determine independent predictors and cutoff values of remission. The postoperative outcome was defined as remission using the 2010 consensus criteria of acromegaly.

RESULTS

One hundred and thirty six patients (97.1%) achieved gross total resection. The postoperative long-term BR was 68.6%. Empty sella, tumor maximum diameter and postoperative GH levels were independent factors predicting remission. ROC revealed that postoperative 24 h GH ≤ 1.3 ng/mL and  ≤ 1.23 ng/mL were valuable predictors for 3-month and long-term remission respectively, and that postoperative 3-month GH ≤ 1.6 ng/mL and tumor maximum diameter  ≤ 17 mm were predictors for delayed remission.

CONCLUSION

Early postoperative GH levels can be used as predictors of remission. However, BR was not associated with preoperative somatostatin analogs therapy or Knosp grade (0-2). For patients without residual tumor or recurrence and whose GH levels are slightly elevated within 1 year after surgery, adjuvant treatments may not be necessary.

Isomeric thermally activated delayed fluorescence emitters for highly efficient organic light-emitting diodes

The isomeric strategy is an important design concept in molecular design that has a non-negligible influence on molecular properties. Herein, two isomeric thermally activated delayed fluorescence (TADF) emitters (NTPZ and TNPZ) are constructed with the same skeleton consisting of an electron donor and electron acceptor but different connection sites. Systematic investigations show that NTPZ exhibits a small energy gap, large up-conversion efficiency, low non-radiative decay, and high photoluminescence quantum yield. Further theoretical simulations reveal that the excited molecular vibrations play a key role in regulating the non-radiative decays of the isomers. Therefore, an NTPZ based OLED achieves better electroluminescence performances, such as a higher external quantum efficiency of 27.5% compared to a TNPZ based OLED (18.3%). This isomeric strategy not only provides an opportunity to deeply understand the relationship between substituent locations and molecular properties, but also affords a simple and effective strategy to enrich TADF materials.

Switchable and Highly Robust Ultralong Room-Temperature Phosphorescence from Polymer-Based Transparent Films with Three-Dimensional Covalent Networks for Erasable Light Printing

In this work, an efficient polymer-based organic afterglow system, which shows reversible photochromism, switchable ultralong organic phosphorescence (UOP), and prominent water and chemical resistance simultaneously, has been developed for the first time. By doping phenoxazine (PXZ) and 10-ethyl-10H-phenoxazine (PXZEt) into epoxy polymers, the resulting PXZ@EP-0.25 % and PXZEt@EP-0.25 % films show unique photoactivated UOP properties, with phosphorescence quantum yields and lifetimes up to 10.8 % and 845 ms, respectively. It is found that the steady-state luminescence and UOP of PXZ@EP-0.25 % are switchable by light irradiation and thermal annealing. Moreover, the doped films can still produce conspicuous UOP after soaking in water, strong acid and base, and organic solvents for more than two weeks, exhibiting outstanding water and chemical resistance. Inspired by these exciting results, the PXZ@EP-0.25 % has been successfully exploited as an erasable transparent film for light printing.

Color-Tunable Dual-Mode Organic Afterglow from Classical Aggregation-Caused Quenching Compounds for White-Light-Manipulated Anti-Counterfeiting

Color-tunable dual-mode organic afterglow excited by ultraviolet (UV) and white light was achieved from classical aggregation-caused quenching compounds for the first time. Specifically, two luminescent systems, which could produce significant organic afterglow composed of persistent thermally activated delayed fluorescence and ultralong organic phosphorescence under ambient conditions, were constructed by doping fluorescein sodium and calcein sodium into aluminum sulfate. Their lifetimes surpassed 600 ms, and the dopant concentrations were as low as 5×10^-6  wt %. Moreover, the persistent luminescence colors of the materials could be tuned from blue to green and then to yellow by simply varying the concentrations of guest compounds or the temperature in the range of 260-340 K. Inspired by these exciting results, the afterglow materials were used for UV- and white-light-manipulated anti-counterfeiting and preparation of elastomers with different colors of persistent luminescence.

Conservative versus liberal oxygen therapy in relation to all-cause mortality among patients in the intensive care unit: a systematic review of randomized controlled trials with meta-analysis and trial sequential analysis

OBJECTIVE

To evaluate the benefits and harmful effects of conservative versus liberal oxygen therapy in patients admitted to the Intensive Care Unit (ICU).

DESIGN

A systematic review and meta-analysis was carried out.

SETTING

ICU.

PARTICIPANTS

Adult patients (aged 18 years or older) were randomized to either a lower oxygenation target strategy (conservative oxygen therapy) or a higher oxygenation target strategy (liberal oxygen therapy) in the ICU.

INTERVENTIONS

Patients received different oxygenation target strategies.

RESULTS

Ten studies involving 5429 adult patients admitted to the ICU were included in the meta-analysis. The pooled results showed no decreased all-cause mortality at 28 days (RR 0.90; 95%CI 0.75-1.09; p = 0.28), 90 days (RR 1.02; 95%CI 0.92-1.13; p = 0.71) or longest follow-up (RR 0.97; 95%CI 0.88-1.08; p = 0.63) among patients administered conservative oxygen therapy. Secondary outcomes were comparable between the two groups. The results of sensitivity analyses and subgroup analyses were consistent with the main analyses.

CONCLUSION

No beneficial or harmful effects of conservative oxygen therapy were found compared to liberal oxygen therapy in relation to all-cause mortality among adult patients in the ICU. Conservative oxygen therapy did not reduce all-cause mortality at 28 days, 90 days or longest follow-up. Other important clinical outcomes were also comparable between the two groups.

A dish-like molecular architecture for dynamic ultralong room-temperature phosphorescence through reversible guest accommodation

Developing dynamic organic ultralong room-temperature phosphorescent (URTP) materials is of practical importance in various applications but remains a challenge due to the difficulty in manipulating aggregate structures. Herein, we report a dish-like molecular architecture via a bottom-up way, featuring guest-responsive dynamic URTP. Through controlling local fragment motions in the molecular architecture, fascinating dynamic URTP performances can be achieved in response to reversible accommodation of various guests, including solvents, alkyl bromides and even carbon dioxide. Large-scale regulations of phosphorescence lifetime (100-fold) and intensity (10-fold) can be realized, presenting a maximum phosphorescence efficiency and lifetime of 78.8% and 483.1 ms, respectively. Moreover, such a dish-like molecular architecture is employed for temperature-dependent multiple information encryption and visual identification of linear alkyl bromides. This work can not only deepen our understanding to construct multifunctional organic aggregates, but also facilitate the design of high-performance dynamic URTP materials and enrich their practical applications.

Hot dense silica glass with ultrahigh elastic moduli

Silicate and oxide glasses are often chemically doped with a variety of cations to tune for desirable properties in technological applications, but their performances are often limited by relatively lower mechanical and elastic properties. Finding a new route to synthesize silica-based glasses with high elastic and mechanical properties needs to be explored. Here, we report a dense SiO₂-glass with ultra-high elastic moduli using sound velocity measurements by Brillouin scattering up to 72 GPa at 300 K. High-temperature measurements were performed up to 63 GPa at 750 K and 59 GPa at 1000 K. Compared to compression at 300 K, elevated temperature helps compressed SiO₂-glass effectively overcome the kinetic barrier to undergo permanent densification with enhanced coordination number and connectivity. This hot compressed SiO₂-glass exhibits a substantially high bulk modulus of 361–429 GPa which is at least 2–3 times greater than the metallic, oxide, and silicate glasses at ambient conditions. Its Poisson’s ratio, an indicator for the packing efficiency, is comparable to the metallic glasses. Even after temperature quench and decompression to ambient conditions, the SiO₂-glass retains some of its unique properties at compression and possesses a Poisson’s ratio of 0.248(11). In addition to chemical alternatives in glass syntheses, coupled compression and heating treatments can be an effective means to enhance mechanical and elastic properties in high-performance glasses.

Asymmetric Thermally Activated Delayed Fluorescence Emitter for Highly Efficient Red/Near-Infrared Organic Light-Emitting Diodes

Developing highly efficient red/near-infrared thermally activated delayed fluorescence (TADF) materials is of great importance for organic light-emitting diodes (OLEDs). Here, we reported an asymmetric TADF emitter (TCPQ), which exhibits a high reverse intersystem crossing rate as well as a low non-radiative rate due to molecular symmetry breaking through multiple donor substitution. The coexistence of multiple donors endows TCPQ with not only near-infrared emission but also excellent device performances. As for the TCPQ-based OLEDs, the 10 and 20 wt % doped devices exhibit outstanding external quantum efficiencies (EQEs) of 21.9 and 19.2% with red emission peaks at 612 and 642 nm, respectively. Meanwhile, the non-doped device achieves an EQE of 5.4% with an emission peak at 718 nm, showing near-infrared emission. These device efficiencies are among the best performances of red/near-infrared TADF-OLEDs, demonstrating that the asymmetry design is a potential strategy for constructing long wavelength TADF materials with high efficiency.

Study of the spatio-temporal variation of environmental sustainability at national and provincial levels in China

Environmental problems create a significant barrier for China in achieving its Sustainable Development Goals (SDGs). Assessing environmental sustainability is critical for China to meet the SDGs. Few studies, however, have looked into environmental sustainability in China. This research created a systematic and comprehensive environmental sustainability framework in line with the SDGs (SDG 6, SDG 11, SDG 12, SDG 13, SDG 14, SDG 15). From 2010 to 2018, we used a Constant Elasticity of Substitution (CES) model to assess China's spatio-temporal variation in environmental sustainability at the national and provincial levels. We also evaluated the results with changes to the substitution elasticity value, validating the feasibility of the proposed calculation method. Our results show that the scores of SDG 6, SDG 11, SDG 12, SDG 13, and SDG 15 experienced an increasing trend, while SDG 14 experienced a decline. China's Environmental Sustainability Index (ESI) scores indicate that China's overall environmental sustainability has been improved over time. At the provincial level, the ESI scores of all provinces increased at different levels from 2010 to 2018. The results of this paper may facilitate improvements in environmentally-related SDGs in China's provinces, and help realize China's sustainable development.

Enhanced acetic acid sensing of MOF-derived α-Fe2O3/ZrO2 arising from phase junction and defects

The coexistence of phase junction, heterojunction and defects allows α-Fe2O3/ZrO2 to display an significant response towards acetic acid.

Negative associations of morning serum cortisol levels with obesity: the Henan rural cohort study

AIMS

To evaluate the associations of morning serum cortisol levels with obesity defined by different indices in Chinese rural populations.

MATERIALS AND METHODS

A cross-sectional study was performed including 6198 participants (2566 males and 3632 females). Serum cortisol was collected in morning and quantified by liquid chromatography-tandem mass spectrometry. Obesity was defined by body mass index (BMI), body fat percentage (BFP), waist-to-height ratio (WHtR), waist circumference (WC), visceral fat index (VFI) and waist-to-hip ratio (WHR). Both multivariable liner regression, logistic regression and restrictive cubic splines models were used to estimate the gender-specific relationships between cortisol levels and obesity defined by different indices, respectively.

RESULTS

After adjusting for potential confounders, serum cortisol was negatively associated with different obesity measures, except obese females defined by BFP (for instance, overall obesity defined by BMI, Quartile 4 vs. Quartile 1, odds ratio (OR) = 0.25, 95% confidence interval (CI):0.15, 0.41 in males, and OR = 0.58, 95% CI: 0.42,0.80 in females, central obesity defined by WC, OR = 0.52, 95% CI:0.39,0.69 in males and OR = 0.63, 95% CI:0.51,0.77 in females). Similarly, restrictive cubic splines showed the nonlinear relationship between high levels of cortisol and different obesity indices. Furthermore, ROC curve analysis indicated that cortisol could improve the discrimination of model with common biomarkers.

CONCLUSION

Morning serum cortisol were negatively related to obesity defined by different indices in Chinese rural populations. In addition, cortisol could be as a biomarker for prediction of obesity in males.

Operando Raman spectroscopic evidence of electron-phonon interactions in NiO/TiO2 pn junction photodetectors

The pn junctions significantly affect the responsivity of photodetectors (PDs). However, the enhancement mechanism of the pn junction is still unclear. Herein, operando Raman spectroscopy was employed to study PDs with NiO/TiO₂ pn junctions composed of p-NiO nanoparticles (NPs) and n-TiO₂ nanotube arrays (TNAs). The results suggest that the built-in potential field of the NiO/TiO₂ interface decreases the charge transfer resistance and changes the vibrational frequency of the phonon modes of TiO₂, which is attributed to the electron-phonon coupling effect. Operando Raman spectroscopy is proved to be a powerful tool for manufacturing highly responsive PDs.

Regulation mechanism of miR-494-3p on endometrial receptivity in mice via PI3K/AKT/mTOR pathway

Successful implantation requires endometrial receptivity. To investigate the mechanisms of miR-494-3p on endometrial receptivity, GnRHa's superovulation scheme was designed to reduce endometrial receptivity, and the pregnant mice were injected with miR-494-3p antagomir. The regulatory role of miR-494-3p was identified by RT-qPCR, uterine blastocyst count, scanning electron microscopy, hematoxylin-eosin (HE) staining, and Western blot. Results indicated that miR-494-3p antagomir increased uterine blastocysts numbers, promoted the pinocytosis expressions, and increased endometrial thickness. Besides, miR-494-3p antagomir significantly increased leukemia inhibitory factor (LIF), Ang-2 and VEGF protein expressions, and up-regulated p-AKT/AKT and p-mTOR/mTOR protein ratios in endometrium. Luciferase assay confirmed that LIF was a potential target of miR-494-3p. Subsequently, human endometrial epithelial cells (hEECs) were transfected with miR-494-3p inhibitor and PI3K inhibitor (LY294002). The role of miR-494-3p was identified by RT-qPCR, CCK-8 assay, transwell assay and flow cytometry. Results indicated that miR-494-3p inhibitor significantly increased proliferation and invasion, and significantly inhibited apoptosis in hEECs, while LY294002 reversed its biological function. Overall, these results suggested that miR-494-3p is the key regulator of endometrial receptivity in mice, regulating this complex process through the PI3K/AKT/mTOR pathway. Understanding the role of miR-494-3p in endometrial receptivity is of great significance for exploring new targets for the diagnosis and treatment of early pregnancy failure, and improving the success rates of artificial reproduction.

Silver nanoparticle-decorated TiO2 nanotube array for solid-phase microextraction and SERS detection of antibiotic residue in milk

The excessive use or abuse of antibiotics on dairy cows leads to residues in milk, which can represent a public health risk. However, in recent years the β-Lactamase was illegally used to degrade residual antibiotics in milk, which makes the traditional antibiotic detection methods ineffective. Therefore, there is an extremely urgent need for multi-analyte analysis techniques for the detection of antibiotic residues. Herein, we reported an ultra-fast, facile, and sensitive solid-phase microextraction (SPME)-surface enhanced Raman scattering (SERS) platform for the detection of degraded antibiotics-2-mercapto-5-methyl-1,3,4-thiadiazole (MMT). The results showed that the log-log plot of SERS intensity to MMT concentration exhibits a superior linear relationship (R² = 0.992) in the concentration range of 0.5-1000 μM, with a detection limit of 0.11 μM. The silver nanoparticle-decorated TiO₂ nanotube array was successfully used as an all-in-one SPME-SERS substrate in the extraction and identification of the antibiotic degradation products in real milk. Due to the rapid pre-treatment, good reproducibility, and self-cleaning, the proposed SPME-SERS method has a great promise to be applied as a powerful tool for on-site detection in the field of food safety.

POS0401 THE APPLICATION OF MTX-LOADING DNA TETRAHEDRON IN TREATING COLLAGEN-INDUCED ARTHRITIS MICE VIA REGULATING MACROPHAGE

Background:

Rheumatoid arthritis (RA) is a systemic autoimmune disease which mainly affect joints. [1]. Macrophages often infiltrate in the inflammatory joints. Activated macrophages release TNF-α, IL-1β to accelerate tissue damage, is one of the most important targets for RA intervention. The traditional drugs currently used commonly have some disadvantages cannot be bypassed[2], while DNA nanostructure is a new type of drugs have precise design, and likewise takes biological effect together[3]. We synthesized a DNA tetrahedron loaded with MTX and conjugated with HA which targeted to macrophage.

Objectives:

To verify whether MTX-loading DNA tetrahedron can regulate the apoptosis and polarization of macrophage and finally improve the condition of CIA model mice by while decrease the side effect of MTX.

Methods:

DNA TET was synthesized by mixing signal strand DNA in TM buffer and heated to 95 °C for 10 min, then cooling to 4 °C. Electrophoresis was applied to confirm the formation of TET. The absorbance of MTX solution was detected by microplate reader to analyze the loading efficiency of MTX into TET. Fluorescence microscope was used to observe the intake of TET into cells. CCK8 experiment was applied to measure the vitality of cells. Flow cytometry was used to detect the apoptosis and polarization. CIA model was established based on DBA/1 mice. Mice were randomly divided into five groups: normal group injected with NS; after established CIA model, CIA group injected with NS, MTX group injected with MTX solution, MTX-TET group injected with MTX-TET NP.

Results:

We synthesized DNA tetrahedron(A) and used 8% PAGE electrophoresis to confirmed the successfully synthesis(B). Then We found that when TET concentration fixed, the loading MTX concentration gradually increased and saturated at 190μM(C). While completely loading needed at least 4 hours(D). Fluorescence showed that single DNA strand cannot be taken by RAW, while TET can be easily taken by RAW(E). CCK8 showed that empty TET had no obvious effect on cells, while MTX and MTX-TET with equivalent concentration can obviously suppress the vitality(F). Similarly, the apoptosis trial showed that TET can slightly decrease the apoptosis of RAW, MTX and MTX-TET can significantly promote the apoptosis(G). Flow cytometry showed that the MTX-TET can decrease the expression of M1 marker CD80 (H).

At last, we treat mice with NS, TET, MTX and MTX-TET once a week after CIA model established, and found that TET have no significantly effect on mice, while MTX and MTX-TET can alleviate the inflammation symptom of paws(I).

Conclusion:

Conclusions: We synthesized MTX-loading DNA tetrahedron conjugated with HA, and found that the MTX-TET NP have the excellent ability of promote RAW apoptosis and relieve proinflammatory M1 polarization. while also can alleviate the symptom of CIA mice.

References:

[1]Aletaha D, Smolen JS: Diagnosis and Management of Rheumatoid Arthritis: A Review. JAMA 2018, 320(13):1360-1372.

[2]Smolen JS, Aletaha D, McInnes IB: Rheumatoid arthritis. Lancet 2016, 388(10055):2023-2038.

[3]Hu Q, Li H, Wang L, Gu H, Fan C: DNA Nanotechnology-Enabled Drug Delivery Systems. Chem Rev 2019, 119(10):6459-6506.

Figure 1.

Disclosure of Interests:

None declared

Segregated oceanic crust trapped at the bottom mantle transition zone revealed from ambient noise interferometry

The recycling of oceanic crust, with distinct isotopic and chemical signature from the pyrolite mantle, plays a critical role in the chemical evolution of the Earth with insights into mantle circulation. However, the role of the mantle transition zone during this recycling remains ambiguous. We here combine the unique resolution reflected body waves (P410P and P660P) retrieved from ambient noise interferometry with mineral physics modeling, to shed new light on transition zone physics. Our joint analysis reveals a generally sharp 660-km discontinuity and the existence of a localized accumulation of oceanic crust at the bottom mantle transition zone just ahead of the stagnant Pacific slab. The basalt accumulation is plausibly derived from the segregation of oceanic crust and depleted mantle of the adjacent stagnant slab. Our findings provide direct evidence of segregated oceanic crust trapped within the mantle transition zone and new insights into imperfect whole mantle circulation.

A SERS Study of Charge Transfer Process in Au Nanorod-MBA@Cu2O Assemblies: Effect of Length to Diameter Ratio of Au Nanorods

Surface-enhanced Raman scattering (SERS) is a powerful tool in charge transfer (CT) process research. By analyzing the relative intensity of the characteristic bands in the bridging molecules, one can obtain detailed information about the CT between two materials. Herein, we synthesized a series of Au nanorods (NRs) with different length-to-diameter ratios (L/Ds) and used these Au NRs to prepare a series of core-shell structures with the same Cu2O thicknesses to form Au NR-4-mercaptobenzoic acid (MBA)@Cu2O core-shell structures. Surface plasmon resonance (SPR) absorption bands were adjusted by tuning the L/Ds of Au NR cores in these assemblies. SERS spectra of the core-shell structure were obtained under 633 and 785 nm laser excitations, and on the basis of the differences in the relative band strengths of these SERS spectra detected with the as-synthesized assemblies, we calculated the CT degree of the core-shell structure. We explored whether the Cu2O conduction band and valence band position and the SPR absorption band position together affect the CT process in the core-shell structure. In this work, we found that the specific surface area of the Au NRs could influence the CT process in Au NR-MBA@Cu2O core-shell structures, which has rarely been discussed before.

Hybridized local and charge-transfer excited state fluorophores enabling organic light-emitting diodes with record high efficiencies close to 20

Pure organic emitters with full utilization of triplet excitons are in high demand for organic light-emitting diodes (OLEDs). Herein, through modulation of electron donors and introduction of phenyl rings as π spacers, we present three pure organic fluorophores (BCz, BTCz and BPTCz) with the hybridized local and charge-transfer (HLCT) excited state feature for OLED fabrication. Importantly, the introduction of π spacers in BPTCz not only enhances locally excited character with a fast radiative decay but also promotes intermolecular interactions to suppress non-radiative decays, contributing to a high solid-state fluorescence efficiency over 90%. Significantly, BPTCz not only endows its doped OLEDs with an external quantum efficiency (EQE) up to 19.5%, but also its non-doped OLED with a high EQE of 17.8%, and these outstanding efficiencies are the state-of-the-art performances of HLCT-based OLEDs.

Three purely organic fluorophores with a hybridized local and charge-transfer excited state feature are presented and enabled organic light-emitting diodes with record high external quantum efficiencies close to 20%.

Photo-Induced Charge Transfer Enhancement for SERS in a SiO2-Ag-Reduced Graphene Oxide System

Understanding and controlling the disorder in materials, especially the disorder caused by structural composition and doping effects, are important keys to studying the optical characteristics of materials. In this study, a SiO₂-Ag-reduced graphene oxide (rGO) composite structure was prepared by a simple wet chemical method, in which Ag nanoparticles (NPs) and SiO₂ were decorated onto the surface of rGO. The introduction of Si atoms can control not only the plasmon effect of Ag NPs but also, more importantly, the defect concentration of rGO. The formation of defects causes the rGO structure to enter a metastable state, which facilitates charge separation and transfer in the system. It is worth noting that changes in defect concentration can affect the energy band position of rGO; therefore, controlling the defect concentration can be used to achieve charge transfer resonance coupling. This study not only revealed the ultrahigh surface-enhanced Raman scattering activity of the substrate structure but also elucidated in detail the effect of the crystallinity of this rGO-based composite system on its optical properties.

Carbazole isomers induce ultralong organic phosphorescence

Commercial carbazole has been widely used to synthesize organic functional materials that have led to recent breakthroughs in ultralong organic phosphorescence¹, thermally activated delayed fluorescence^2,3, organic luminescent radicals⁴ and organic semiconductor lasers⁵. However, the impact of low-concentration isomeric impurities present within commercial batches on the properties of the synthesized molecules requires further analysis. Here, we have synthesized highly pure carbazole and observed that its fluorescence is blueshifted by 54 nm with respect to commercial samples and its room-temperature ultralong phosphorescence almost disappears⁶. We discover that such differences are due to the presence of a carbazole isomeric impurity in commercial carbazole sources, with concentrations <0.5 mol%. Ten representative carbazole derivatives synthesized from the highly pure carbazole failed to show the ultralong phosphorescence reported in the literature^1,7-15. However, the phosphorescence was recovered by adding 0.1 mol% isomers, which act as charge traps. Investigating the role of the isomers may therefore provide alternative insights into the mechanisms behind ultralong organic phosphorescence^1,6-18.

Measurement of single-diffractive dijet production in proton-proton collisions at s = 8 Te with the CMS and TOTEM experiments

Measurements are presented of the single-diffractive dijet cross section and the diffractive cross section as a function of the proton fractional momentum loss ξ and the four-momentum transfer squared t. Both processesp p → p X andp p → X p , i.e. with the proton scattering to either side of the interaction point, are measured, whereX includes at least two jets; the results of the two processes are averaged. The analyses are based on data collected simultaneously with the CMS and TOTEM detectors at the LHC in proton-proton collisions ats = 8 Te during a dedicated run withβ ∗ = 90 m at low instantaneous luminosity and correspond to an integrated luminosity of 37.5 nb - 1 . The single-diffractive dijet cross section σ jj p X , in the kinematic region ξ < 0.1 ,0.03 < | t | < 1 Ge 2 , with at least two jets with transverse momentump T > 40 Ge , and pseudorapidity | η | < 4.4 , is 21.7 ± 0.9 (stat) - 3.3 + 3.0 (syst) ± 0.9 (lumi) nb . The ratio of the single-diffractive to inclusive dijet yields, normalised per unit of ξ , is presented as a function of x, the longitudinal momentum fraction of the proton carried by the struck parton. The ratio in the kinematic region defined above, for x values in the range - 2.9 ≤ log 10 x ≤ - 1.6 , is R = ( σ jj p X / Δ ξ ) / σ jj = 0.025 ± 0.001 (stat) ± 0.003 (syst) , where σ jj p X and σ jj are the single-diffractive and inclusive dijet cross sections, respectively. The results are compared with predictions from models of diffractive and nondiffractive interactions. Monte Carlo predictions based on the HERA diffractive parton distribution functions agree well with the data when corrected for the effect of soft rescattering between the spectator partons.

Measurement of single-diffractive dijet production in proton-proton collisions at s = 8 Te with the CMS and TOTEM experiments

Measurements are presented of the single-diffractive dijet cross section and the diffractive cross section as a function of the proton fractional momentum loss ξ and the four-momentum transfer squared t. Both processes p p → p X and p p → X p , i.e. with the proton scattering to either side of the interaction point, are measured, where X includes at least two jets; the results of the two processes are averaged. The analyses are based on data collected simultaneously with the CMS and TOTEM detectors at the LHC in proton-proton collisions at s = 8 Te during a dedicated run with β ∗ = 90 m at low instantaneous luminosity and correspond to an integrated luminosity of 37.5 nb - 1 . The single-diffractive dijet cross section σ jj p X , in the kinematic region ξ < 0.1 , 0.03 < | t | < 1 Ge 2 , with at least two jets with transverse momentum p T > 40 Ge , and pseudorapidity | η | < 4.4 , is 21.7 ± 0.9 (stat) - 3.3 + 3.0 (syst) ± 0.9 (lumi) nb . The ratio of the single-diffractive to inclusive dijet yields, normalised per unit of ξ , is presented as a function of x, the longitudinal momentum fraction of the proton carried by the struck parton. The ratio in the kinematic region defined above, for x values in the range - 2.9 ≤ log 10 x ≤ - 1.6 , is R = ( σ jj p X / Δ ξ ) / σ jj = 0.025 ± 0.001 (stat) ± 0.003 (syst) , where σ jj p X and σ jj are the single-diffractive and inclusive dijet cross sections, respectively. The results are compared with predictions from models of diffractive and nondiffractive interactions. Monte Carlo predictions based on the HERA diffractive parton distribution functions agree well with the data when corrected for the effect of soft rescattering between the spectator partons.

Ensemble deep learning with multi-objective optimization for prognosis of rotating machinery

With the emerging of Internet of Things and smart sensing techniques, enormous monitoring data has been collected by prognostics and health management (PHM) systems. Predicting the Remaining useful life (RUL) of mechanical components from monitoring data has always been a challenging task in many industries, yet determining RUL accurately is identified as one of the most demanded outcomes of PHM systems. In this study, an ensemble deep learning with multi-objective optimization (EDL-MO) method is proposed for RUL prediction. A novel ensemble deep learning algorithm for RUL prediction is designed by combining accuracy and diversity. By introducing the diversity, uncorrelated error is produced in each individual iteration, and performance of prediction will be improved by evolving deep networks. The presented EDL-MO employs evolutionary optimization to optimize the two conflicting objectives, that is, diversity and accuracy. To validate the proposed algorithm, bearing run-to-failure experiments were carried out under constant load. The vibration signals are recorded and utilized to predict the RUL by using the proposed EDL-MO method, as well as other existing methods for performance comparison. The effectiveness and superiority of EDL-MO are analyzed, which outperforms the current algorithms in predicting RUL on rotation machineries.

Soft salts based on platinum(II) complexes with high emission quantum efficiencies in the near infrared region for in vivo imaging

Two soft salts (S1 and S2) based on platinum(ii) complexes with a near-infrared emission have been designed and synthesized. It has been demonstrated that S2 has a high photostability and a low cytotoxicity, and it has been successfully applied to in vivo imaging for the first time.

Studies of Charm Quark Diffusion inside Jets Using Pb-Pb and pp Collisions at sqrt[s_{NN}]=5.02 TeV

The first study of charm quark diffusion with respect to the jet axis in heavy ion collisions is presented. The measurement is performed using jets with p_{T}^{jet}>60  GeV/c and D^{0} mesons with p_{T}^{D}>4  GeV/c in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of sqrt[s_{NN}]=5.02  TeV, recorded by the CMS detector at the LHC. The radial distribution of D^{0} mesons with respect to the jet axis is sensitive to the production mechanisms of the meson, as well as to the energy loss and diffusion processes undergone by its parent parton inside the strongly interacting medium produced in Pb-Pb collisions. When compared to Monte Carlo event generators, the radial distribution in pp collisions is found to be well described by pythia, while the slope of the distribution predicted by sherpa is steeper than that of the data. In Pb-Pb collisions, compared to the pp results, the D^{0} meson distribution for 4<p_{T}^{D}<20  GeV/c hints at a larger distance on average with respect to the jet axis, reflecting a diffusion of charm quarks in the medium created in heavy ion collisions. At higher p_{T}^{D}, the Pb-Pb and pp radial distributions are found to be similar.