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Imine-linked covalent organic frameworks (COFs) have been widely studied in the field of photocatalytic hydrogen production due to their easy synthesis, good crystallinity, tunable pore size and excellent thermal and chemical stability. However, the effect of substituent type on the photocatalytic properties of COFs has been rarely studied. Herein, six COFs with COF-TpPa as the basic skeleton were synthesized by introducing different types of substituents in the p-phenylenediamine benzene ring, among which TpPa-CN2 was prepared for the first time. The COFs showed similar structures but great differences in their photoelectric properties. TpPa-Cl2 and TpPa-CN2 demonstrated a superior hydrogen evolution performance compared to the other four COFs when ascorbic acid was used as the electron sacrificial agent and Pt as the cocatalyst. The photocatalytic hydrogen evolution (PHE) rate of TpPa-Cl2 and TpPa-CN2 was as high as 99.23 and 76.93 mmol g−1 h−1, respectively. The introduction of chlorine and cyanide improved the visible-light response, hydrophilicity and photo-carrier separation ability of TpPa COF, which contributed to the enhanced PHE efficiency of TpPa-Cl2 and TpPa-CN2. This study provides a strong basis for the systematic fine-tuning of the structural and physico-chemical properties of COFs aiming to achieve COF materials with ultra-high photocatalytic activity. [ABSTRACT FROM AUTHOR]

The decline in female fertility as age advances is intricately linked to the diminished developmental potential of oocytes. Despite this challenge, the strategies available to enhance the quality of aged oocytes remain limited. Epigallocatechin‐3‐gallate (EGCG), characterised by its anti‐inflammatory, antioxidant and tissue protective properties, holds promise as a candidate for improving the quality of maternally aged oocytes. In this study, we explored the precise impact and underlying mechanisms of EGCG on aged oocytes. EGCG exhibited the capacity to enhance the quality of aged oocytes both in vitro and in vivo. Specifically, the application of EGCG in vitro resulted in noteworthy improvements, including an increased rate of first polar body extrusion, enhanced mitochondrial function, refined spindle morphology and a reduction in oxidative stress. These beneficial effects were further validated by the improved fertility observed among aged mice. In addition, our findings propose that EGCG might augment the expression of Arf6. This augmentation, in turn, contributes to the assembly of spindle‐associated F‐actin, which can contribute to mitigate the aneuploidy induced by the disruption of spindle F‐actin within aged oocytes. This work thus contributes not only to understanding the role of EGCG in bolstering oocyte health, but also underscores its potential as a therapeutic intervention to address fertility challenges associated with advanced age. [ABSTRACT FROM AUTHOR]

Introduction: Frozen embryo transfer is associated with a higher rate of live birth and a lower risk for ovarian hyperstimulation syndrome in women with polycystic ovary syndrome (PCOS) compared with fresh embryo transfer. The aim of this study is to assess the optimal endometrial preparation protocol for women with PCOS undergoing frozen embryo transfer. Material and methods: We conducted a historical cohort analysis of 1720 women with PCOS who underwent the "freeze‐all" strategy between August 2014 and August 2017 because of their high risk for ovarian hyperstimulation syndrome. Three endometrial preparation protocols were used: natural cycle (NC; n = 191), which relies on the dominant follicle to secrete estrogen that then promotes endometrial growth; ovarian stimulation (OS; n = 96), which induces follicle growth using low doses of human menopausal gonadotropin; and hormone replacement (HRT; n = 1433), which uses exogenous estradiol to promote endometrial growth. The primary outcome was live birth. Results: For women who received a single embryo transfer, the live birth rates for the NC, OS, and HRT groups were 62.4%, 65.0%, and 52.2%, respectively. The live birth rate in the HRT group was significantly lower than that seen in the OS and NC groups (P =.009). The clinical pregnancy rates of the three groups were 72.3%, 73.8%, and 64.9%, respectively; this difference did not reach statistical significance (P =.071). Conclusions: The rate of live birth with the NC and OS regimens was higher than with the HRT protocol in women with PCOS who undergo single‐blastocyst frozen embryo transfer. [ABSTRACT FROM AUTHOR]

Polycystic ovary syndrome (PCOS) is the most common complex endocrine and metabolic disease in women of reproductive age. It is characterized by anovulatory infertility, hormone disorders, and polycystic ovarian morphology. Regarding the importance of granulosa cells (GCs) in the pathogenesis of PCOS, few studies have investigated the etiology at a single "omics" level, such as with an mRNA expression array or methylation profiling assay, but this can provide only limited insights into the biological mechanisms. Here, genome-wide DNA methylation together with lncRNA-miRNA-mRNA profiles were simultaneously detected in GCs of PCOS cases and controls. A total of 3579 lncRNAs, 49 miRNAs, 669 mRNAs, and 890 differentially methylated regions (DMR)-associated genes were differentially expressed between PCOS cases and controls. Pathway analysis indicated that these differentially expressed genes were commonly associated with steroid biosynthesis and metabolism-related signaling, such as glycolysis/gluconeogenesis. In addition, we constructed ceRNA networks and identified some known ceRNA axes, such as lncRNAs-miR-628-5p-CYP11A1/HSD17B7. We also identified many new ceRNA axes, such as lncRNAs-miR-483-5p-GOT2. Interestingly, most ceRNA axes were also closely related to steroid biosynthesis and metabolic pathways. These findings suggest that it is important to systematically consider the role of reproductive and metabolic genes in the pathogenesis of PCOS. [ABSTRACT FROM AUTHOR]

Background: Women who undergo chronic exposure to excessive estrogen are at a high risk of developing breast cancer. TOX3 has been reported to be highly expressed in breast tumors and is closely related to estrogen receptors. However, the effect of TOX3 on estrogen synthesis remains poorly understood. Methods: Using lentiviruses as a vector, we stably overexpressed TOX3 in the ovarian granulosa cell line KGN, the cells where estradiol is primarily produced, to investigate its role in estrogen production as well as cell viability and apoptosis. RNA-Sequencing was applied to uncover the global gene expression upon TOX3 overexpression. Results: We observed an increased level of cell viability and a reduced cell apoptosis rate after TOX3 overexpression, and the level of estradiol in the cell culture supernatant also increased significantly. Gene set enrichment analysis of the transcriptome showed that the ovarian steroidogenesis pathway was significantly enriched. Similarly, pathway mapping using the Kyoto Encyclopedia of Genes and Genomes and Gene Ontology analyses also showed that TOX3 overexpression affects the ovarian steroidogenesis pathway. Further experiments showed that upregulated FSHR , CYP19A1 , and BMP6 accounted for the enhanced estrogen synthesis. Conclusion: Our study demonstrated that TOX3 quantitatively and qualitatively stimulates estrogen synthesis by enhancing estrogen signaling pathway–related gene expression in ovarian granulosa cells. These findings suggest that TOX3 may play a vital role in the pathogenesis of breast cancer. [ABSTRACT FROM AUTHOR]

This study investigated whether rs1784692 is a risk factor for polycystic ovary syndrome (PCOS) in Han Chinese women. A case-control study was conducted in Han Chinese women, involving 526 PCOS patients and 522 control participants. A TaqMan MGB probe assay was used to genotype the variant rs1784692. Dominant and additive models were employed for genotype–phenotype association analysis in the PCOS and control samples. The minor allele C of rs1784692 is protective against PCOS (odds ratio [OR] 0.556, 95% confidence interval [CI] 0.408–0.759, P = 1.83 × 10–4), even after adjustment for body mass index (BMI) and age (OR adj 0.539, 95% CI 0.391–0.743, P adj = 1.62 × 10–4). Genotype–phenotype analysis of the dominant model showed that mean BMI in the CC+CT group was higher than in the TT group in the PCOS group (27.12 ± 5.82 versus 24.57 ± 4.52, P = 1.0 × 10–3), but not in the control groups, indicating that the minor allele C of rs1784692 associates with BMI in women with PCOS. The mean LH (luteinizing hormone) concentration in the CC+CT group was lower than in the TT group in PCOS and control participants (9.33 ± 5.08 versus 10.93 ± 5.91, P = 0.036; 4.39 ± 1.66 versus 4.89 ± 2.07, P = 0.021). Genotype–phenotype analysis of additive model showed that mean BMI in TC group was higher than in the TT group in PCOS patients compared with control participants (27.14 ± 5.81 versus 24.57 ± 4.52, P = 3.06 × 10–3). The SNP rs1784692 in gene ZBTB16 is protective against PCOS but is associated with increased BMI in Han Chinese women with PCOS. [ABSTRACT FROM AUTHOR]

Synergetic effects in Au–Ag bimetallic nanoclusters (BNCs) more favorably enhanced electrochemical redox induced electrochemiluminescence (ECL) over photoexcitation induced photoluminescence (PL); this not only led to Au–Ag BNCs with enhanced bandgap-engineered ECL compared to Au NCs, but it also generated surface-defect related ECL to enhance the total ECL intensity. [ABSTRACT FROM AUTHOR]

Quinolone antibiotic residues may pose potential threat to human health. A rapid and sensitive method was developed for the determination of quinolone residues in human serum and urine. After solid phase extraction (SPE) process, eight quinolone residues were analyzed by high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) using ciprofloxacin-d8 as the internal standard. The relative standard deviation of intra-day and inter-day precision for the eight quinolones were less than 7.52% and the accuracies ranged from 95.8% to 103% in human serum, and from 94.1% to 104% in human urine. The extraction recoveries for the eight quinolones varied from 80.2% to 113% in human serum and 83.4% to 117% in human urine. The limit of detection for the eight quinolones was 0.50–1.00 ng/mL. Quinolone antibiotic residues in human serum and urine from 12 volunteers were successfully analyzed with the validated method. The SPE-HPLC-MS/MS method was useful for accurate determination of quinolone antibiotic residues in human body. [ABSTRACT FROM AUTHOR]

In this research, epigenetic effects of bisphenol A (BPA) on human breast cancer MCF-7 cells were analyzed. Genome-wide DNA methylation and gene expression were analyzed in MCF-7 cells exposed to BPA (10−5 and 10−6 mol/L for 5 weeks). No significant changes in the global level of 5-methyl-2′-deoxycytidine and 5-hydroxymethyl-2′-deoxycytidine were observed. DNA methylation profiling analysis indicated that BPA exposure resulted in the hypermethylation of FOXK2, LKB1, LMX1A and CUGBP2 and the hypomethylation of PTPRN2, TRIM27, BCAS3 and ZNF423. Decreased expression of apoptosis genes (P38 and BCL2L1) and increased expression of chemokine (Cxcl2 and ccl20) were detected. Changes of these genes were speculated to affect the ERα-related cell growth as well as cell apoptosis. [ABSTRACT FROM AUTHOR]

5-hydroxymethyl-2′-deoxycytidine (5-hmdC), which plays important roles in the epigenetic remodeling in mammals, has been recently determined in plant genomes at trace concentrations. In this study, a method for the sensitive, specific, and rapid assessment of 5-hmdC in rice is reported using high-performance liquid chromatography–tandem mass spectrometry (HPLC–tandem MS) with isotope dilution. The recovery of this method was from 75.6% to 81.3% for 5-hmdC and the intra- and inter-day precision values were within 5.81%. The quantification limit for 5-hmdC was 5.0 pM. Genomic DNA from rice was extracted and enzymatically digested for nucleotides for the HPLC–tandem MS assay. The 5-hmdC levels were 1.32 ± 0.08, 1.64 ± 0.12, and 1.98 ± 0.07 modifications per million nucleosides in the Shengdao-18, Shengxiang-145, and Jindao-263 rice cultivars. The application of HPLC–tandem MS for 5-hmdC demonstrated its presence in the genomic DNA of rice and is useful in further studying the role of modified cytosine in the epigenetic regulation of rice. [ABSTRACT FROM PUBLISHER]

A simple synthesis route is reported for generation of hierarchically porous Zn/Al layered double hydroxides (LDHs) by using urea and trisodium citrate (TSC) as precipitating agent and structure-directing agent, respectively. The structure, morphology and textural properties of the as-prepared LDH solids were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and nitrogen adsorption-desorption techniques. It was found that the flowerlike Zn/Al-LDHs hierarchically porous assemblies were constructed from hexagonal nanosheets with different sizes. Pseudo-second-order kinetic model was turn out to fit the experimental data well. The adsorption data were better described using the Langmuir adsorption isotherm with excellent adsorption capacity of 98.7 mg/g towards parachlorophenol in water. [ABSTRACT FROM PUBLISHER]

TiO2-coated LiNi1/3Co1/3Mn1/3O2 materials were prepared by the hydrolyzation of Ti(OBu)4. The impact of TiO2 coating on the structure and electrochemical properties of LiNi1/3Co1/3Mn1/3O2 was investigated using X-ray diffraction, scanning electron microscope, and charge–discharge tests. The results indicated that TiO2 coating did not affect the lattice of LiNi1/3Co1/3Mn1/3O2, but exhibited obvious effects on its discharge capacity and cycling stability. As coated TiO2 increased from 0.0 to 2.0 mol%, the initial capacity of samples decreased slightly, but the cycling stability over 2.5∼4.3 V increased remarkably. The capacity retention reached 99.5% at the 50th cycle at a coating amount of 2.0 mol%. [ABSTRACT FROM AUTHOR]

Preparation of LiCoO2 cathode materials from spent lithium–ion batteries are presented. It started with the reclaim/recycle of metal values from spent lithium–ion batteries, which involves the separation of electrode materials by ultrasonic treatment, acid dissolution, precipitation of cobalt and lithium, followed by the preparation of LiCoO2 cathode materials. Co (99.4%) and Li (94.5%) were recovered from spent lithium–ion batteries. The LiCoO2 cathode materials prepared from the reclaimed cobalt and lithium compounds showed good elecrtochemical performance. The reclaiming of cobalt and lithium has a promising outlook for the recycling of cobalt and lithium from spent Li–ion batteries, thus reducing the cost of Li–ion batteries. [ABSTRACT FROM AUTHOR]

Correction for 'Mechanistic investigations into synergistically enhanced radiative-charge-transfer in Au–Ag bimetallic nanoclusters' by Jianbo Liu et al., Chem. Commun., 2020, 56, 5665–5668, DOI: 10.1039/D0CC02047H. [ABSTRACT FROM AUTHOR]

Anaerobic bioelectrochemical digestion (ABD) is widely used for treating wastewater and recovering energy. The electrode is the key point for ABD system, which was sparsely studied with food waste. In this study, a carbon-modified copper foam was fabricated with copper foam and multiple wall carbon nanotubes (MWCNT) through electrophoretic deposition and screen-printing methods. The carbon-modified copper foam electrode was investigated in an ABD reactor for food waste. The features of bioelectrochemical methane production, process stability, and electrochemical characterization were evaluated in the ABD reactor, and were compared to the control reactor without equipping electrode. The ultimate methane production reached 338.1 mL CH4/L in the ABD reactor, which was significantly higher than the 181.0 mL CH4/L of the control reactor. The methane produced from the electrode was 137.8 mL CH4/L, which was up to 40.8% of total methane production in the ABD reactor. It was attributed to the electroactive bacteria that were enriched and activated by the carbon-modified copper foam electrode, further activating the direct interspecies electron transfer (DIET) pathways for methane production. The cyclic voltammetry (CV) analysis showed higher redox peaks, which is one of the pieces of evidence for the enrichment of electroactive bacteria. The carbon-modified copper foam electrode has the advantages of both carbon and metal materials, and demonstrated a high possibility for use in bioelectrochemical methane production for food waste. [ABSTRACT FROM AUTHOR]

Graphene as a two-dimensional (2D) nanoplatform is beneficial for assembling a 2D heterojunction photocatalytic system to promote electron transfer in semiconductor composites. Here a BiVO4 nanosheets/reduced graphene oxide (RGO) based 2D-2D heterojunction photocatalytic system as well as 0D-2D BiVO4 nanoparticles/RGO and 1D-2D BiVO4 nanotubes/RGO nanocomposites are fabricated by a feasible solvothermal process. During the synthesis; the growth of BiVO4 and the intimate interfacial contact between BiVO4 and RGO occur simultaneously. Compared to 0D-2D and 1D-2D heterojunctions, the resulting 2D-2D BiVO4 nanosheets/RGO composites yield superior chemical coupling; leading to exhibit higher photocatalytic activity toward the degradation of acetaminophen under visible light irradiation. Photoluminescence (PL) and photocurrent experiments revealed that the apparent electron transfer rate in 2D-2D BiVO4 nanosheets/RGO composites is faster than that in 0D-2D BiVO4 nanoparticles/RGO composites. The experimental findings presented here clearly demonstrate that the 2D-2D heterojunction interface can highlight the optoelectronic coupling between nanomaterials and promote the electron–hole separation. This study will motivate new developments in dimensionality factors on designing the heterojunction photocatalysts and promote their photodegradation photocatalytic application in environmental issues. [ABSTRACT FROM AUTHOR]

Abstract: Sn doped lithium nickel cobalt manganese composite oxide of LiNi3/8Co2/8Mn3/8−x Sn x O2 (0≤ x ≤0.10) was synthesized by stannum substitute of manganese to enhance its rate capability at first time. Its structure and electrochemical properties were characterized by X-ray diffraction (XRD), SEM, cyclic voltammetry (CV), galvanostatic intermittent titration technique (GITT) and charge/discharge tests. LiNi3/8Co2/8Mn3/8−x Sn x O2 had stable layered structure with α-NaFeO2 type as x up to 0.05, meanwhile, its chemical diffusion coefficient D Li of Li-ion was enhanced by almost one order of magnitude, leading to notable improvement of the rate capability of LiNi3/8Co2/8Mn3/8O2. The compound of x =0.10 showed the best rate capability among Sn doped samples, but its discharge capacity reduced markedly due to secondary phase Li2SnO3 and increase of cation-disorder. The compound with x =0.05 showed high rate capability with initial discharge capacity in excess of 156mAhg−1. It is a promising alternative cathode material for EV application of Li-ion batteries. [Copyright &y& Elsevier]

Achieving both rapid adsorption rate and high adsorption capacity for bisphenol micropollutants from aquatic systems is critical for efficient adsorbents in water remediation. Here, we elaborately prepared three nitrogen-rich triazine-based porous polymers (NTPs) with similar geometric configurations and nitrogen contents (41.70–44.18 wt%) while tunable BET surface areas and micropore volumes in the range of 454.7–536.3 m2 g−1 and 0.20–0.84 cm3 g−1, respectively. It was systematically revealed that the synergy of hydrogen bonding, π−π electron-donor-acceptor interaction, and micropore preservation promoted the rapid (within 5 min) and high capacity adsorption of bisphenols by NTPs. Particularly, microporous-dominated NTPs-3 with the highest micro-pore volume (0.84 cm3 g−1) displays remarkable adsorption capacity towards bisphenol A as evidenced by the adsorption capacity of 182.23 mg g−1. A simple column filter constructed by NTPs-3 also expressed good dynamic adsorption and regeneration capacity. This work provided new insight into the rational design and engineering of nitrogen-rich porous polymers for the remediation of micropollutant wastewater. Three nitrogen-rich triazine-based porous polymers with similar geometric configurations and nitrogen contents while tunable BET surface areas and micropore volumes were used for the adsorption of bisphenol micropollutants. [Display omitted] • NTPs have similar geometric configurations and nitrogen contents while tunable porosities. • The adsorption mechanism is the synergy of hydrogen bonding, π−π interaction, and micropore preservation. • NTPs-3 expressed rapid and high capacity adsorption of bisphenols. • A simple column filter constructed by NTPs expressed good dynamic adsorption and regeneration capacity. [ABSTRACT FROM AUTHOR]

[Display omitted] • K, P, O and S were innovatively simultaneously doped into g-C 3 N 4. • K, P, O, S-g-C 3 N 4 has 12.85 times higher yield of H 2 O 2 than g-C 3 N 4. • The degradation rate of TC by K, P, O, S-g-C 3 N 4 was 1.5 times higher than the pure. • Four elements doping can promote the charge transfer in g-C 3 N 4. • Negatively charged S introduced into the g-C 3 N 4 can facilitate the ·O 2 − production. Elemental doping can modulate the electronic and molecular structure of g-C 3 N 4 to improve its photocatalytic properties. In this study, potassium (K), phosphorus (P), oxygen (O), and sulfur (S) were doped into the g-C 3 N 4 photocatalyst (K, P, O, S/g-C 3 N 4), and the four-element doped photocatalyst was successfully prepared. UV–vis diffuse reflection spectroscopy, photoluminescence, and transient photocurrent revealed that the co-doping of g-C 3 N 4 with K, P, O and S broadens the visible response and accelerates the transfer of photogenerated charges. Under visible light irradiation, the H 2 O 2 concentration produced with K, P, O, S/g-C 3 N 4 was 12.85 times higher than that with g-C 3 N 4. Moreover, tetracycline (TC) can be effectively degraded by the photocatalyst in surface water. The degradation pathway of TC and the molecular structures of 12 intermediates were analyzed by liquid chromatography-mass spectrometry. The superoxide radical (·O 2 −) trapping-electron spin resonance (ESR) technique confirmed that ·O 2 − is the main active species in the system. Therefore, the four-element doping strategy adopted in this research proved the feasibility of increasing the amount of H 2 O 2 produced and degrading the antibiotics in natural water under visible light. [ABSTRACT FROM AUTHOR]

Nickel aluminum layered double hydroxides (LDHs) fabricated via sodium citrate (SC) assistant hydrothermal route were evaluated for removing p-nitrophenol from aqueous solutions. The characterization results indicate that the NiAl-LDHs nanoparticles have well-ordered layer structure with highly crystalline nature. The NiAl-LDH possessed hierarchically porous nanoarchitectures with high surface area (108.7 m 2 /g) and great pore volume (0.41 cm 3 /g). Meanwhile, interlamellar spacing of NiAl-LDH was increased to 0.73 nm, demonstrating that the citric acid ion was intercalated into NiAl-LDH in vertical alignment. The morphology of NiAl-LDH changed from a series of disordered growth hexagon nanosheets to the flower-like microspheres with modification of variable sodium citrate. The adsorption isotherms of p-nitrophenol on NiAl-LDHs obey the Langmuir equation. It is worthy to note that the NiAl-LDH modified by sodium citrate with the addition of 2.316 g exhibits excellent adsorption performance with the maximum p-nitrophenol adsorption capacity of 77.7 mg/g. [ABSTRACT FROM AUTHOR]