Ruthenium Anchored Laser-Induced Graphene as Binder-Free and Free-Standing Electrode for Selective Electrosynthesis of Ammonia from Nitrate.

Developing effective electrocatalysts for the nitrate reduction reaction (NO3RR) is a promising alternative to conventional industrial ammonia (NH3) synthesis. Herein, starting from a flexible laser-induced graphene (LIG) film with hierarchical and interconnected macroporous architecture, a binder-free and free-standing Ru-modified LIG electrode (Ru-LIG) is fabricated for electrocatalytic NO3RR via a facile electrodeposition method. The relationship between the laser-scribing parameters and the NO3RR performance of Ru-LIG electrodes is studied in-depth. At -0.59 VRHE, the Ru-LIG electrode exhibited the optimal and stable NO3RR performance (NH3 yield rate of 655.9 µg cm-2 h-1 with NH3 Faradaic efficiency of up to 93.7%) under a laser defocus setting of +2 mm and an applied laser power of 4.8 W, outperforming most of the reported NO3RR electrodes operated under similar conditions. The optimized laser-scribing parameters promoted the surface properties of LIG with increased graphitization degree and decreased charge-transfer resistance, leading to synergistically improved Ru electrodeposition with more exposed NO3RR active sites. This work not only provides a new insight to enhance the electrocatalytic NO3RR performance of LIG-based electrodes via the coordination with metal electrocatalysts as well as identification of the critical laser-scribing parameters but also will inspire the rational design of future advanced laser-induced electrocatalysts for NO3RR.

Technology of plant factory for vegetable crop speed breeding.

Sustaining crop production and food security are threatened by a burgeoning world population and adverse environmental conditions. Traditional breeding methods for vegetable crops are time-consuming, laborious, and untargeted, often taking several years to develop new and improved varieties. The challenges faced by a long breeding cycle need to be overcome. The speed breeding (SB) approach is broadly employed in crop breeding, which greatly shortens breeding cycles and facilities plant growth to obtain new, better-adapted crop varieties as quickly as possible. Potential opportunities are offered by SB in plant factories, where optimal photoperiod, light quality, light intensity, temperature, CO2 concentration, and nutrients are precisely manipulated to enhance the growth of horticultural vegetable crops, holding promise to surmount the long-standing problem of lengthy crop breeding cycles. Additionally, integrated with other breeding technologies, such as genome editing, genomic selection, and high-throughput genotyping, SB in plant factories has emerged as a smart and promising platform to hasten generation turnover and enhance the efficiency of breeding in vegetable crops. This review considers the pivotal opportunities and challenges of SB in plant factories, aiming to accelerate plant generation turnover and improve vegetable crops with precision and efficiency.

Complex Patterns of Antihypertensive Treatment Changes in Long-Term Care Residents.

OBJECTIVES: Antihypertensive treatment changes are common in long-term care residents, yet data on the frequency and predictors of changes are lacking. We described the patterns of antihypertensive changes and examined the triggering factors. DESIGN: Retrospective cohort study. SETTING AND PARTICIPANTS: A total of 24,870 Department of Veterans Affairs (VA) nursing home residents aged ≥65 years with long-term stays (≥180 days) from 2006 to 2019. METHODS: We obtained data from the VA Corporate Data Warehouse. Based on Bar Code Medication Administration medication data, we defined 2 types of change events in 180 days of admission: deprescribing (reduced number of antihypertensives or dose reduction of ≥30% compared with the previous week and maintained for at least 2 weeks) and intensification (opposite of deprescribing). Mortality was identified within 2 years after admission. RESULTS: More than 85% of residents were prescribed antihypertensives and 68% of them experienced ≥1 change event during the first 6 months of the nursing home stay. We categorized residents into 10 distinct patterns: no change (27%), 1 deprescribing (11%), multiple deprescribing (5%), 1 intensification (10%), multiple intensification (7%), 1 deprescribing followed by 1 intensification (3%), 1 intensification followed by 1 deprescribing (4%), 3 changes with mixed events (7%), >3 changes with mixed events (10%), and no antihypertensive use (15%). Treatment changes were more frequent in residents with better physical function and/or cognitive function. Potentially triggering factors differed by the type of antihypertensive change: incident high blood pressure and cardiovascular events were associated with intensification, and low blood pressure, weight loss, and falls were associated with deprescribing. Death occurred in 7881 (32%) residents over 2 years. The highest mortality was for those without antihypertensive medication (incidence = 344/1000 person-years). CONCLUSIONS AND IMPLICATIONS: Patterns of medication changes existing in long-term care residents are complex. Future studies should explore the benefits and harms of these antihypertensive treatment changes.

Effects of xenogeneic transplantation of umbilical cord-derived mesenchymal stem cells combined with irbesartan on renal podocyte damage in diabetic rats.

BACKGROUND: The leading cause of end-stage renal disease (ESRD) is diabetic nephropathy (DN). Podocyte damage is an early event in the development of DN. Currently, there is no effective treatment strategy that can slow the progression of DN or reverse its onset. The role of mesenchymal stem cells (MSCs) transplantation in diabetes and its complications has been extensively studied, and diabetic nephropathy has been a major focus. Irbesartan exerts reno-protective effects independent of lowering blood pressure, can reduce the incidence of proteinuria in rats, and is widely used clinically. However, it remains undetermined whether the combined utilization of the angiotensin II receptor antagonist irbesartan and MSCs could enhance efficacy in addressing DN. METHODS: A commonly used method for modeling type 2 diabetic nephropathy (T2DN) was established using a high-fat diet and a single low-dose injection of STZ (35 mg/kg). The animals were divided into the following 5 groups: (1) the control group (CON), (2) the diabetic nephropathy group (DN), (3) the mesenchymal stem cells treatment group (MSCs), (4) the irbesartan treatment group (Irb), and (5) the combined administration group (MSC + Irb). MSCs (2 × 106 cells/rat) were injected every 10 days through the tail vein for a total of three injections; irbesartan (30 mg/kg/d) was administered by gavage. Additionally, the safety and homing of mesenchymal stem cells were verified using positron emission tomography (PET) imaging. RESULTS: The combination treatment significantly reduced the UACR, kidney index, IGPTT, HOMA-IR, BUN, serum creatine, and related inflammatory factor levels and significantly improved renal function parameters and the expression of proteins related to glomerular podocyte injury in rats. Moreover, MSCs can homing target to damaged kidneys. CONCLUSIONS: Compared to the administration of MSCs or irbesartan alone, the combination of MSCs and irbesartan exerted better protective effects on glomerular podocyte injury, providing new ideas for the clinical application of mesenchymal stem cells.

The characteristics of PtHSP40 gene family in Phaeodactylum tricornutum and its response to environmental stresses.

Diatom has evolved response mechanisms to cope with multiple environmental stresses. Heat shock protein 40 (HSP40) plays a key role in these response mechanisms. HSP40 gene family in higher plants has been well-studied. However, the HSP40 gene family has not been systematically investigated in marine diatom. In this study, the bioinformatic characteristics, phylogenetic relationship, conserved motifs, gene structure, chromosome distribution and the transcriptional response of PtHSP40 to different environmental stresses were analyzed in the diatom Phaeodactylum tricornutum, and quantitative real-time PCR was conducted. Totally, 55 putative PtHSP40 genes are distributed to 21 chromosomes. All PtHSP40 proteins can be divided into four groups based on their evolutionary relationship, and 54 of them contain a conserved HPD (histidine-proline-aspartic acid tripeptide) motif. Additionally, six, eleven, ten and four PtHSP40 genes were significantly upregulated under the treatments of nitrogen starvation, phosphorus deprivation, 2,2',4,4'-tetrabrominated biphenyl ether (BDE-47) and ocean acidification, respectively. More interestingly, the expression level of 9 PtHSP40 genes was obviously upregulated in response to nickel stress, suggesting the sensitive to metal stress. The different expression models of PtHSP40 genes to environmental stresses imply the specificity of PtHSP40 proteins under different stresses. This study provides a systematic understanding of the PtHSP40 gene family in P. tricornutum and a comprehensive cognition in its functions and response mechanisms to environmental stresses.

Cluster of Differentiation 36 (CD36) Preferentially Mediates Intestinal Absorption of Dietary Z-Astaxanthin and Especially 9-Z-Isomer via Higher Binding Affinity.

Variances in the biological functions of astaxanthin geometric isomers (i.e., all-E, Z) are related to their intestinal absorption, but the mechanism of isomer absorption mediated by transporters remains unclear. Here, models of in vitro cell overexpression, in situ intestinal perfusion, and in vivo mouse inhibition were employed to investigate the impact of cluster of differentiation 36 (CD36) on the absorption of astaxanthin isomers. Cells overexpressing CD36 notably enhanced the uptake of Z-astaxanthin, particularly the 9-Z-isomer (47.76%). The absorption rate and permeability of Z-astaxanthin surpassed that of the all-E-isomer by the in situ model. Furthermore, the addition of the CD36-specific inhibitor sulfo-N-succinimidyl oleate significantly reduced the absorption of Z-astaxanthin in the mouse duodenum and jejunum, especially the 9-Z-isomer (57.66%). Molecular docking and surface plasmon resonance techniques further validated that 9-Z-astaxanthin binds to more amino acids of CD36 with higher affinity and in a fast-binding, fast-dissociating mode, thus favoring transport. Our findings elucidate, for the first time, the mechanism of the CD36-mediated transmembrane transport of astaxanthin geometric isomers.

Enhanced choroid plexus segmentation with 3D UX-Net and its association with disease progression in multiple sclerosis.

BACKGROUND: The choroid plexus (CP) is suggested to be closely associated with the neuroinflammation of multiple sclerosis (MS). Segmentation based on deep learning (DL) could facilitate rapid and reproducible volume assessment of the CP, which is crucial for elucidating its role in MS. PURPOSE: To develop a reliable DL model for the automatic segmentation of CP, and further validate its clinical significance in MS. METHODS: The 3D UX-Net model (3D U-Net used for comparison) was trained and validated on T1-weighted MRI from a cohort of 216 relapsing-remitting MS (RRMS) patients and 75 healthy subjects. Among these, 53 RRMS with baseline and 2-year follow-up scans formed an internal test set (dataset1b). Another 58 RRMS from multi-center data served as an external test set (dataset2). Dice coefficient was computed to assess segmentation performance. Compare the correlation of CP volume obtained through automatic and manual segmentation with clinical outcomes in MS. Disability and cognitive function of patients were assessed using the Expanded Disability Status Scale (EDSS) and Symbol Digit Modalities Test (SDMT). RESULTS: The 3D UX-Net model achieved Dice coefficients of 0.875 ± 0.030 and 0.870 ± 0.044 for CP segmentation on dataset1b and dataset2, respectively, outperforming 3D U-Net's scores of 0.809 ± 0.098 and 0.601 ± 0.226. Furthermore, CP volumes segmented by the 3D UX-Net model aligned consistently with clinical outcomes compared to manual segmentation. In dataset1b, both manual and automatic segmentation revealed a significant positive correlation between normalized CP volume (nCPV) and EDSS scores at baseline (manual: r = 0.285, p = 0.045; automatic: r = 0.287, p = 0.044) and a negative correlation with SDMT scores (manual: r = -0.331, p = 0.020; automatic: r = -0.329, p = 0.021). In dataset2, similar correlations were found with EDSS scores (manual: r = 0.337, p = 0.021; automatic: r = 0.346, p = 0.017). Meanwhile, in dataset1b, both manual and automatic segmentation revealed a significant increase in nCPV from baseline to follow-up (p < 0.05). The increase of nCPV was more pronounced in patients with disability worsened than stable patients (manual: p = 0.023; automatic: p = 0.018). Patients receiving disease-modifying therapy (DMT) exhibited a significantly lower nCPV increase than untreated patients (manual: p = 0.004; automatic: p = 0.004). CONCLUSION: The 3D UX-Net model demonstrated strong segmentation performance for the CP, and the automatic segmented CP can be directly used in MS clinical practice. CP volume can serve as a surrogate imaging biomarker for monitoring disease progression and DMT response in MS patients.

Systematic analysis of the expression profiles and prognostic significance of the MED gene family in renal clear cell carcinoma.

The mediator complex (MED) family is a contributing factor in the regulation of transcription and proliferation of cells, and is closely associated with the development of various types of cancer. However, the significance of the expression levels and prognostic value of MED genes in kidney renal clear cell carcinoma (KIRC) have rarely been reported. The present study analyzed the expression and prognostic potential of MED genes in KIRC. The Search Tool for the Retrieval of Interacting Genes/Proteins was used to construct the protein-protein interaction network (PPI), the Assistant for Clinical Bioinformatics database was used to perform correlation analysis, GEPIA 2 was utilized to draw the Kaplan-Meier plot and analyze prognostic significance and the Tumor Immune Estimation Resource was used to assess the association of MED genes with the infiltration of immune cells in patients with KIRC. A total of 30 MED genes were identified, and among these genes, 11 were selected for the creation of a prognostic gene signature based on the results of a LASSO Cox regression analysis. Furthermore, according to univariate and multivariate analyses, MED7, MED16, MED21, MED25 and MED29 may be valuable independent predictive biomarkers for the prognosis of individuals with KIRC. Furthermore, there were significant differences in the expression levels of MED7, MED21 and MED25 in KIRC among different tumor grades. Additionally, patients with KIRC with high transcription levels of MED7, MED21 and MED29 had considerably longer overall survival times. The expression levels of MED genes were also linked to the infiltration of several immune cells. Overall, MED genes may have potential significance in predicting the prognosis of patients with KIRC.

Interaction analysis of RNA G-quadruplex with ligands and in situ imaging application.

RNA G4, as an integral branch of G4 structure, possesses distinct interactions with ligands compared to the common DNA G4, thus the investigation of RNA G4/ligand interactions might be considered as a fresh breakthrough to improve the biosensing performance of G4/ligand system. In this study, we comparatively explored the structural and functional mechanisms of RNA G4 and DNA G4 in the interaction with ligands, hemin and thioflavin T (ThT), utilizing the classical PS2.M sequence as a model. We found that although the catalytic performance of RNA G4/hemin system was lower than DNA G4/hemin, RNA G4/ThT fluorescence system exhibited a significant improvement (2∼3-fold) compared to DNA G4/ThT, and adenine modification could further enhance the signaling. Further, by exploring the interaction between RNA G4 and ThT, we deemed that RNA G4 and ThT were stacked in a bimolecular mode compared to single-molecule binding of DNA G4/ThT, thus more strongly limiting the structural spin in ThT excited state. Further, RNA G4/ThT displayed higher environmental tolerance and lower ion dependence than DNA G4/ThT. Finally, we employed RNA G4/ThT as a highly sensitive label-free fluorescent signal output system for in situ imaging of isoforms BCR-ABL e13a2 and e14a2. Overall, this study successfully screened a high-performance RNA G4 biosensing system through systematic RNA G4/ligands interaction studies, which was expected to provide a promising reference for subsequent G4/ligand research.

3-ketoacyl-CoA synthase 7 from Xanthoceras sorbifolium seeds is a crucial regulatory enzyme for nervonic acid biosynthesis.

Nervonic acid (C24:1) is a very-long-chain fatty acid that plays an imperative role in human brain development and other health benefits. In plants, 3-ketoacyl-CoA synthase (KCS) is the key rate-limiting enzyme for C24:1 biosynthesis. Xanthoceras sorbifolium is a valuable oil-producing economic woody species with abundant C24:1 in seed oils, but the key KCS gene responsible for C24:1 accumulation remains unknown. In this work, a correlation analysis between the transcript profiles of KCS and dynamic change of C24:1 content in developing seeds of X. sorbifolium were conducted to screen out three members of KCS, namely XsKCS4, XsKCS7 and XsKCS8, potentially involved in C24:1 biosynthesis. Of which, the XsKCS7 was highly expressed in developing seeds, while XsKCS4 and XsKCS8 displayed the highest expression in fruits and flowers, respectively. Overexpression of XsKCS4, XsKCS7 and XsKCS8 in yeast Saccharomyces cerevisiae and plant Arabidopsis thaliana indicated that only XsKCS7 possessed the ability to facilitate the biosynthesis of C24:1. These findings collectively suggested that XsKCS7 played a crucial role in specific regulation of C24:1 biosynthesis in X. sorbifolium seeds.

Cytoskeletal and inter-cellular junction remodelling in endometrial organoids under oxygen-glucose deprivation: a new potential pathological mechanism for thin endometria.

STUDY QUESTION: What is the pathological mechanism involved in a thin endometrium, particularly under ischaemic conditions? SUMMARY ANSWER: Endometrial dysfunction in patients with thin endometrium primarily results from remodelling in cytoskeletons and cellular junctions of endometrial epithelial cells under ischemic conditions. WHAT IS KNOWN ALREADY: A healthy endometrium is essential for successful embryo implantation and subsequent pregnancy; ischemic conditions in a thin endometrium compromise fertility outcomes. STUDY DESIGN, SIZE, DURATION: We recruited 10 patients with thin endometrium and 15 patients with healthy endometrium. Doppler ultrasound and immunohistochemical results confirmed the presence of insufficient endometrial blood perfusion in patients with thin endometrium. Organoids were constructed using healthy endometrial tissue and cultured under oxygen-glucose deprivation (OGD) conditions for 24 h. The morphological, transcriptomic, protein expression, and signaling pathway changes in the OGD organoids were observed. These findings were validated in both thin endometrial tissue and healthy endometrial tissue samples. PARTICIPANTS/MATERIALS, SETTING, METHODS: Endometrial thickness and blood flow were measured during the late follicular phase using transvaginal Doppler ultrasound. Endometrial tissue was obtained via hysteroscopy. Fresh endometrial tissues were used for the generation and culture of human endometrial organoids. Organoids were cultured in an appropriate medium and subjected to OGD to simulate ischemic conditions. Apoptosis and cell death were assessed using Annexin-V/propidium iodide staining. Immunofluorescence analysis, RNA sequencing, western blotting, simple westerns, immunohistochemistry, and electron microscopy were conducted to evaluate cellular and molecular changes. MAIN RESULTS AND THE ROLE OF CHANCE: Patients with thin endometrium showed significantly reduced endometrial thickness and altered blood flow patterns compared to those with healthy endometrium. Immunohistochemical staining revealed fewer CD34-positive blood vessels and glands in the thin endometrium group. Organoids cultured under OGD conditions exhibited significant morphological changes, increased apoptosis, and cell death. RNA-seq identified differentially expressed genes related to cytoskeletal remodeling and stress responses. OGD induced a strong cytoskeletal reorganization, mediated by the RhoA/ROCK signaling pathway. Additionally, electron microscopy indicated compromised epithelial integrity and abnormal cell junctions in thin endometrial tissues. Upregulation of hypoxia markers (HIF-1α and HIF-2α) and activation of the RhoA/ROCK pathway were also observed in thin endometrial tissues, suggesting ischemia and hypoxia as underlying mechanisms. LARGE SCALE DATA: none. LIMITATIONS AND REASONS FOR CAUTION: The study was conducted in an in vitro model, which may not fully replicate the complexity of in vivo conditions. WIDER IMPLICATIONS OF THE FINDINGS: This research provides a new three-dimensional in vitro model of thin endometrium, as well as novel insights into the pathophysiological mechanisms of endometrial ischaemia in thin endometrium, offering potential avenues for identifying therapeutic targets for treating fertility issues related to thin endometrium. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by the National Natural Science Foundation of China (81925013); National Key Research and Development Project of China (2022YFC2702500, 2021YFC2700303, 2021YFC2700601); the Capital Health Research and Development Project (SF2022-1-4092); the National Natural Science Foundation of China (82288102, 81925013, 82225019, 82192873); Special Project on Capital Clinical Diagnosis and Treatment Technology Research and Transformation Application (Z211100002921054); the Frontiers Medical Center, Tianfu Jincheng Laboratory Foundation(TFJC2023010001). The authors declare that no competing interests exist.

Health impacts of lifestyle and ambient air pollution patterns on all-cause mortality: a UK Biobank cohort study.

BACKGROUND: Extensive evidence indicates that both lifestyle factors and air pollution are strongly associated with all-cause mortality. However, little studies in this field have integrated these two factors in order to examine their relationship with mortality and explore potential interactions. METHODS: A cohort of 271,075 participants from the UK Biobank underwent analysis. Lifestyles in terms of five modifiable factors, namely smoking, alcohol consumption, physical activity, diet, and sleep quality, were classified as unhealthy (0-1 score), general (2-3 score), and healthy (4-5 score). Air pollution, including particle matter with a diameter ≤ 2.5 µm (PM2.5), particulate matter with a diameter ≤ 10 µm (PM10), particulate matter with a diameter 2.5-10 µm (PM2.5-10), nitrogen dioxide (NO2), and nitrogen oxides (NOx), was divided into three levels (high, moderate, and low) using Latent Profile Analysis (LPA). Cox proportional hazard regression analysis was performed to examine the links between lifestyle, air pollution, and all-cause mortality before and after adjustment for potential confounders. Restricted cubic spline curves featuring three knots were incorporated to determine nonlinear relationships. The robustness of the findings was assessed via subgroup and sensitivity analyses. RESULTS: With unhealthy lifestyles have a significantly enhanced risk of death compared to people with general lifestyles (HR = 1.315, 95% CI, 1.277-1.355), while people with healthy lifestyles have a significantly lower risk of death (HR = 0.821, 95% CI, 0.785-0.858). Notably, the difference in risk between moderate air pollution and mortality risk remained insignificant (HR = 0.993, 95% CI, 0.945-1.044). High air pollution, on the other hand, was independently linked to increased mortality risk as compared to low air pollution (HR = 1.162, 95% CI, 1.124-1.201). The relationship between NOx, PM10, and PM2.5-10 and all-cause mortality was found to be nonlinear (p for nonlinearity < 0.05). Furthermore, no significant interaction was identified between lifestyle and air pollution with respect to all-cause mortality. CONCLUSIONS: Exposure to ambient air pollution elevated the likelihood of mortality from any cause, which was impacted by individual lifestyles. To alleviate this hazard, it is crucial for authorities to escalate environmental interventions, while individuals should proactively embrace and sustain healthy lifestyles.

Integrated Metabolomic-Transcriptomic Analyses of Flavonoid Accumulation in Citrus Fruit under Exogenous Melatonin Treatment.

The flavonoids in citrus fruits are crucial physiological regulators and natural bioactive products of high pharmaceutical value. Melatonin is a pleiotropic hormone that can regulate plant morphogenesis and stress resistance and alter the accumulation of flavonoids in these processes. However, the direct effect of melatonin on citrus flavonoids remains unclear. In this study, nontargeted metabolomics and transcriptomics were utilized to reveal how exogenous melatonin affects flavonoid biosynthesis in "Bingtangcheng" citrus fruits. The melatonin treatment at 0.1 mmol L-1 significantly increased the contents of seven polymethoxylated flavones (PMFs) and up-regulated a series of flavonoid pathway genes, including 4CL (4-coumaroyl CoA ligase), FNS (flavone synthase), and FHs (flavonoid hydroxylases). Meanwhile, CHS (chalcone synthase) was down-regulated, causing a decrease in the content of most flavonoid glycosides. Pearson correlation analysis obtained 21 transcription factors co-expressed with differentially accumulated flavonoids, among which the AP2/EREBP members were the most numerous. Additionally, circadian rhythm and photosynthesis pathways were enriched in the DEG (differentially expressed gene) analysis, suggesting that melatonin might also mediate changes in the flavonoid biosynthesis pathway by affecting the fruit's circadian rhythm. These results provide valuable information for further exploration of the molecular mechanisms through which melatonin regulates citrus fruit metabolism.

Controlled switching thiocarbonylthio end-groups enables interconvertible radical and cationic single-unit monomer insertions and RAFT polymerizations.

To emulate the ordered arrangement of monomer units found in natural macromolecules, single-unit monomer insertion (SUMI) have emerged as a potent technique for synthesizing sequence-controlled vinyl polymers. Specifically, numerous applications necessitate vinyl polymers encompassing both radically and cationically polymerizable monomers, posing a formidable challenge due to the distinct thiocarbonylthio end-groups required for efficient control over radical and cationic SUMIs. Herein, we present a breakthrough in the form of interconvertible radical and cationic SUMIs achieved through the manipulation of thiocarbonylthio end-groups. The transition from a trithiocarbonate (for radical SUMI) to a dithiocarbamate (for cationic SUMI) is successfully accomplished via a radical-promoted reaction with bis(thiocarbonyl) disulfide. Conversely, the reverse transformation utilizes the reaction between dithiocarbamate and bistrithiocarbonate disulfide under a cationic mechanism. Employing this strategy, we demonstrate a series of synthetic examples featuring discrete oligomers containing acrylate, maleimide, vinyl ether, and styrene, compositions unattainable through the SUMI of a single mechanism alone.

Self-Assembled Nanocomposite Based on SrCo0.7Fe0.2Sc0.1O3-δ as an Efficient Intermediate-to-Low-Temperature SOFC Cathode.

The high performance of intermediate-to-low temperature solid oxide fuel cells (ILT-SOFCs) closely depends on the catalytic activity of the cathode material. However, most high-activity perovskite cathodes are rich in Sr and will arise from Sr segregation during the long-term working, resulting in the decay of activity and stability. Herein, by regulating the calcined way and temperature, a type of self-assembled nanocomposite perovskite cathode is developed, the stoichiometric SrCo0.7Fe0.2Sc0.1O3-δ (SCFSc) powder self-separates into a cubic phase (Pm3̅m, Sc-rich) and a tetragonal phase (P4/mmm, Sc-fewer). Meanwhile, a single cubic phase is prepared with the same formula via calcining the SCFSc pellet. It is found that the nanocomposite cathode shows better oxygen reduction reaction catalytic activity than single cubic SCFSc, caused by lower impedance of oxygen surface exchange and bulk diffusion. Particularly, the nanocomposite SCFSc cathode with the self-assembled heterointerfaces mitigates the Sr segregation and shows a peak power density of 1.17 W cm-2 at 700 °C and excellent stability for ∼101 h at 600 °C. This work provides a strategy for the development of nanocomposite cathodes to mitigate cation segregation and improve catalytic activity and stability.

Unexpected weakened formation of disinfection byproducts and enhanced production of halates by cupric oxide during chlorination of peptide-bound aspartic acid.

Under the condition that the residual chlorine is guaranteed, the biofilm still thrives in drinking water distribution systems through secreting a large number of extracellular polymeric substances (EPS), in which protein components are the primary precursor of disinfection byproducts (DBPs), mostly in the form of combined amino acids. The aim of this study is to investigate the action of CuO on the formation of halates (XO3-, ClO3- and BrO3-) and DBPs (trihalomethanes, THMs; haloacetonitriles, HANs) with aspartic acid tetrapeptide (TAsp) as protein surrogate. The presence of CuO promoted the self-decay rather than TAsp-induced decay of oxidants, resulting in an increase in XO3- yield and a decrease in DBPs yield. It was CuO-induced weaker production of cyanoacetic acid and 3-oxopropanoic acid that induced the decreased yields of HANs and THMs, respectively. The FTIR and Raman spectra indicate a weak complexation between CuO and TAsp. Given this, the CuO-HOX/OX- complexes were inferred to be reactive to HOX/OX- but less reactive to TAsp. The study helps to better understand the formation of XO3- and DBPs during the chlorination of EPS, and propose precise control strategies when biofilm boosts in water pipes.

Mycorrhizal associations modify tree diversity-productivity relationships across experimental tree plantations.

Decades of studies have demonstrated links between biodiversity and ecosystem functioning, yet the generality of the relationships and the underlying mechanisms remain unclear, especially for forest ecosystems. Using 11 tree-diversity experiments, we tested tree species richness-community productivity relationships and the role of arbuscular (AM) or ectomycorrhizal (ECM) fungal-associated tree species in these relationships. Tree species richness had a positive effect on community productivity across experiments, modified by the diversity of tree mycorrhizal associations. In communities with both AM and ECM trees, species richness showed positive effects on community productivity, which could have resulted from complementarity between AM and ECM trees. Moreover, both AM and ECM trees were more productive in mixed communities with both AM and ECM trees than in communities assembled by their own mycorrhizal type of trees. In communities containing only ECM trees, species richness had a significant positive effect on productivity, whereas species richness did not show any significant effects on productivity in communities containing only AM trees. Our study provides novel explanations for variations in diversity-productivity relationships by suggesting that tree-mycorrhiza interactions can shape productivity in mixed-species forest ecosystems.

Landscape of the gut mycobiome dynamics during pregnancy and its relationship with host metabolism and pregnancy health.

OBJECTIVE: The remodelling of gut mycobiome (ie, fungi) during pregnancy and its potential influence on host metabolism and pregnancy health remains largely unexplored. Here, we aim to examine the characteristics of gut fungi in pregnant women, and reveal the associations between gut mycobiome, host metabolome and pregnancy health. DESIGN: Based on a prospective birth cohort in central China (2017 to 2020): Tongji-Huaxi-Shuangliu Birth Cohort, we included 4800 participants who had available ITS2 sequencing data, dietary information and clinical records during their pregnancy. Additionally, we established a subcohort of 1059 participants, which included 514 women who gave birth to preterm, low birthweight or macrosomia infants, as well as 545 randomly selected controls. In this subcohort, a total of 750, 748 and 709 participants had ITS2 sequencing data, 16S sequencing data and serum metabolome data available, respectively, across all trimesters. RESULTS: The composition of gut fungi changes dramatically from early to late pregnancy, exhibiting a greater degree of variability and individuality compared with changes observed in gut bacteria. The multiomics data provide a landscape of the networks among gut mycobiome, biological functionality, serum metabolites and pregnancy health, pinpointing the link between Mucor and adverse pregnancy outcomes. The prepregnancy overweight status is a key factor influencing both gut mycobiome compositional alteration and the pattern of metabolic remodelling during pregnancy. CONCLUSION: This study provides a landscape of gut mycobiome dynamics during pregnancy and its relationship with host metabolism and pregnancy health, which lays the foundation of the future gut mycobiome investigation for healthy pregnancy.

Portable and Flexible Hydrogel Sensor for On-Site Atrazine Assay on Agricultural Products.

There is growing attention focused toward the problems of ecological sustainability and food safety raised from the abuse of herbicides, which underscores the need for the development of a portable and reliable sensor for simple, rapid, and user-friendly on-site analysis of herbicide residues. Herein, a novel multifunctional hydrogel composite is explored to serve as a portable and flexible sensor for the facile and efficient analysis of atrazine (ATZ) residues. The hydrogel electrode is fabricated by doping graphite-phase carbon nitride (g-C3N4) into the aramid nanofiber reinforced poly(vinyl alcohol) hydrogel via a simple solution-casting procedure. Benefiting from the excellent electroactivity and large specific surface area of the solid nanoscale component, the prepared hydrogel sensor is capable of simple, rapid, and sensitive detection of ATZ with a detection limit down to 0.002 ng/mL and per test time less than 1 min. After combination with a smartphone-controlled portable electrochemical analyzer, the flexible sensor exhibited satisfactory analytical performance for the ATZ assay. We further demonstrated the applications of the sensor in the evaluation of the ATZ residues in real water and soil samples as well as the user-friendly on-site point-of-need detection of ATZ residues on various agricultural products. We envision that this flexible and portable sensor will open a new avenue on the development of next-generation analytical tools for herbicide monitoring in the environment and agricultural products.