Water-catalyzed iron-molybdenum carbyne formation in bimetallic acetylene transformation.

Transition metal carbyne complexes are of fundamental importance in carbon-carbon bond formation, alkyne metathesis, and alkyne coupling reactions. Most reported iron carbyne complexes are stabilized by incorporating heteroatoms. Here we show the synthesis of bioinspired FeMo heterobimetallic carbyne complexes by the conversion of C2H2 through a diverse series of intermediates. Key reactions discovered include the reduction of a µ-η2:η2-C2H2 ligand with a hydride to produce a vinyl ligand (µ-η1:η2-CH = CH2), tautomerization of the vinyl ligand to a carbyne (µ-CCH3), and protonation of either the vinyl or the carbyne compound to form a hydrido carbyne heterobimetallic complex. Mechanistic studies unveil the pivotal role of H2O as a proton shuttle, facilitating the proton transfer that converts the vinyl group to a bridging carbyne.

Gut microbiota and myocardial infarction: A bibliometric analysis from 2004 to 2023.

Background: In recent years, numerous studies have suggested that the gut microbiota and its metabolites are closely related to myocardial infarction. Utilizing insights from these research findings may be advantageous in the prevention, treatment, and prognosis of myocardial infarction. We have employed bibliometric methodology to summarize the progress made in this research area over the past 20 years, identify the hotspots, and highlight the developmental tendencies, providing a reference for future research in this field. Methods: We searched the content related to this field in the Web of Science Core Collection database, with a time range from 2001 to 2023. We used VOSviewer, CiteSpace, and Scimago Graphica software to visualize the search results. Results: We included 889 reports in this study. The country with the most publications was China, while the country with the greatest influence was the United States. An analysis of institutions showed that the Chinese Academy of Medical Sciences had the largest volume of publications, whereas the Cleveland Clinic had the most influential ones. An author analysis showed Stanley L Hazen to have published the most and to also have been the most influential researcher. An analysis of all the journals publishing articles related to the search terms showed that PLoS One journal had the highest number of publications (18 articles), while Atherosclerosis journal had the most influential articles. The results of our reference analysis showed a strong association between Trimethylamine N-oxide and myocardial infarction. We found that increased intestinal permeability may be related to the progression of cardiovascular diseases, a high-fiber diet may help in the prevention of diseases such as myocardial infarction, and populations with a high intake of red meat may have an increased risk of myocardial infarction. Keyword analysis suggested that 'cardiac fibrosis' and 'major bleeding' were promising research directions in the future, and supplementing food intake with short-chain fatty acids was looked upon as a promising approach to treating coronary heart disease. Conclusion: The gut microbiota are closely related to myocardial infarction, and investigating this relationship is crucial for the prevention and treatment of myocardial infarction, where interdisciplinary research and international cooperation are indispensable.

Synthesis of MoS2@MoO3/(Cu+/g-C3N4) ternary composites with double S-scheme heterojunction for peroxymonosulfate activation exposing to visible light.

The construction of semiconductor heterojunction is an effective way for charge separation in photocatalytic degradation of pollutants. In this study, a novel MoS2@MoO3/(Cu+/g-C3N4) ternary composites (MMCCN) was prepared via a simple calcination method. The as-prepared composites exhibited exceptional performance in activating peroxymonosulfate (PMS) for the degradation of rhodamine B (RhB). The activity testing results indicated that 99.41 % of RhB (10 mg·L-1, 10 mL) was effectively removed by the synergistic effect of composites photocatalyst (0.1 g·L-1) and PMS (0.1 g·L-1) under visible light irradiation for 40 min. Its reaction rate constant exceeded that of Cu+/g-C3N4, MoO3 and MoS2 by a factor of 3.56, 17.30 and 11.73 times, respectively. The crystal structure, band gap and density of states (DOS) of the semiconductors were calculated according to the density functional theory (DFT). Free radical trapping tests and electron spin resonance spectroscopy validated that 1O2, O2- and h+ are primary reactive species participating in the decomposition of RhB. The ternary composites demonstrated good stability and maintained excellent degradation efficiency even across four reaction cycles. Furthermore, the activation mechanism and the intermediates produced during the decomposition course of RhB by MMCCN/PMS/vis system were analyzed and elucidated. A double S-scheme heterojunctions was responsible for efficient separation of photo-induced electron-hole pairs. This work presents a novel method in the construction of double S-scheme heterojunctions for PMS activation which is expected to find wide applications in wastewater treatment and environmental remediation.

Cushing's syndrome caused by giant Ewing's sarcoma of the kidney: A case report and review of literature.

BACKGROUND: Primary renal Ewing's sarcoma (ES) is extremely rare, and only two cases causing Cushing's syndrome (CS) have been reported to date. We report that the case of an 18-year-old patient is diagnosed primary renal ES with typical CS characterized by purple stripes, weight gain, and hypertension. CASE SUMMARY: CS was first diagnosed by laboratory testing. A huge tumor was revealed in the kidney following an imaging examination. Moreover, brain and bone metastases were observed. After comprehensive treatment, primarily based on surgery, primary renal ES was pathologically diagnosed with a typical EWSR1-FLI1 genetic mutation through genetic testing. Furthermore, the glucocorticoid level returned to normal. By the ninth postoperative month of follow-up, the patient was recovering well. Cushing-related symptoms had improved, and a satisfactory curative effect was achieved. CONCLUSION: Primary renal ES, a rare adult malignant tumor, can cause CS and a poor prognosis.

Design of a Thermally Stable Heat-Resistant (Al2O3+Al3Ti)/Al Composite with Excellent High-Temperature Mechanical Properties: Multimechanism Synergistic Strengthening Strategy.

The effectiveness of the room-temperature strengthening strategy for aluminum (Al) is compromised at increased temperatures due to grain and precipitate phase coarsening. Overcoming the heightened activity of grain boundaries and dislocations poses a significant challenge in enhancing the high-temperature strength through traditional precipitation strengthening. This study presents novel strengthening strategies that integrate intergranular reinforcements, intragranular reinforcements, refined grain, and stacking faults within an (Al2O3+Al3Ti)/Al composite prepared using sol-gel and powder metallurgy technology. Excellent high-temperature tensile properties are achieved; also, a remarkable fatigue performance at increased temperatures that surpasses those of other existing Al alloys and composites is revealed. These superior characteristics can be attributed to its exceptionally stable microstructure and the synergistic strengthening mechanisms mentioned above. This work offers new insights into designing and fabricating thermally stable Al matrix composites for high-temperature applications.

Synthesis and Characterization of Bridging-Diazene Diiron Half-Sandwich Complexes: The Role of Sulfur Hydrogen Bonding.

We report two bridging-diazene diiron complexes [Cp*Fe(8-quinolinethiolate)]2(µ-N2H2) (1-N2H2) and [Cp*Fe(1,2-Cy2PC6H4S)]2(µ-N2H2) (2-N2H2), synthesized by the reaction of hydrazine with the corresponding thiolate-based iron half-sandwich complex, [Cp*Fe(8-quinolinethiolate)]2 (1) and Cp*Fe(1,2-Cy2PC6H4S) (2). Crystallographic analysis reveals that the thiolate sites in 1-N2H2 and 2-N2H2 can engage in N-H···S hydrogen bonding with the diazene protons. 1-N2H2 is thermally stable in both solid and solution states, allowing for one-electron oxidation to afford a cationic diazene radical complex [1-N2H2]+ at room temperature. In contrast, 2-N2H2 tends to undergo N2H2/N2 transformation, leading to the formation of a Fe(III)-H species by the loss of N2. In addition to stabilizing HN=NH species through the hydrogen bonding, the thiolate-based ligands also seem to facilitate proton-coupled electron transfer, thereby promoting N-H cleavage.

Ribonuclease 4 functions as an intestinal antimicrobial protein to maintain gut microbiota and metabolite homeostasis.

Antimicrobial proteins contribute to host-microbiota interactions and are associated with inflammatory bowel disease (IBD), but our understanding on antimicrobial protein diversity and functions remains incomplete. Ribonuclease 4 (Rnase4) is a potential antimicrobial protein with no known function in the intestines. Here we find that RNASE4 is expressed in intestinal epithelial cells (IEC) including Paneth and goblet cells, and is detectable in human and mouse stool. Results from Rnase4-deficient mice and recombinant protein suggest that Rnase4 kills Parasutterella to modulate intestinal microbiome, thereby enhancing indoleamine-2,3-dioxygenase 1 (IDO1) expression and subsequently kynurenic and xanthurenic acid production in IECs to reduce colitis susceptibility. Furthermore, deceased RNASE4 levels are observed in the intestinal tissues and stool from patients with IBD, correlating with increased stool Parasutterella. Our results thus implicate Rnase4 as an intestinal antimicrobial protein regulating gut microbiota and metabolite homeostasis, and as a potential diagnostic biomarker and therapeutic target for IBD.

Simultaneous Manipulation of Membrane Enthalpy and Entropy Barriers towards Superior Ion Separations.

Sub-nanoporous membranes with ion selective transport functions are important for energy utilization, environmental remediation, and fundamental bioinspired engineering. Although mono/multivalent ions can be separated by monovalent ion selective membranes (MISMs), the current theory fails to inspire rapid advances in MISMs. Here, we apply transition state theory (TST) by regulating the enthalpy barrier (ΔH) and entropy barrier (ΔS) for designing next-generation monovalent cation exchange membranes (MCEMs) with great improvement in ion selective separation. Using a molecule-absorbed porous material as an interlayer to construct a denser selective layer can achieve a greater absolute value of ΔS for Li+ and Mg2+ transport, greater ΔH for Mg2+ transport and lower ΔH for Li+ transport. This recorded performance with a Li+/Mg2+ perm-selectivity of 25.50 and a Li+ flux of 1.86 mol ⋅ m-2 ⋅ h-1 surpasses the contemporary "upper bound" plot for Li+/Mg2+ separations. Most importantly, our synthesized MCEM also demonstrates excellent operational stability during the selective electrodialysis (S-ED) processes for realizing scalability in practical applications.

LAZY4 acts additively with the starch-statolith-dependent gravity-sensing pathway to regulate shoot gravitropism and tiller angle in rice.

Rice tiller angle is a key agronomic trait that has significant effects on the establishment of a high-yield rice population. However, the molecular mechanism underlying the control of rice tiller angle remains to be clarified. Here, we characterized the novel tiller-angle gene LAZY4 (LA4) in rice through map-based cloning. LA4 encodes a C3H2C3-type RING zinc-finger E3 ligase localized in the nucleus, and an in vitro ubiquitination assay revealed that the conserved RING finger domain is essential for its E3 ligase activity. We found that expression of LA4 can be induced by gravistimulation and that loss of LA4 function leads to defective shoot gravitropism caused by impaired asymmetric auxin redistribution upon gravistimulation. Genetic analysis demonstrated that LA4 acts in a distinct pathway from the starch biosynthesis regulators LA2 and LA3, which function in the starch-statolith-dependent pathway. Further genetic analysis showed that LA4 regulates shoot gravitropism and tiller angle by acting upstream of LA1 to mediate lateral auxin transport upon gravistimulation. Our studies reveal that LA4 regulates shoot gravitropism and tiller angle upstream of LA1 through a novel pathway independent of the LA2-LA3-mediated gravity-sensing mechanism, providing new insights into the rice tiller-angle regulatory network.

Engineering sub-organelles of a diploid Saccharomyces cerevisiae to enhance the production of 7-dehydrocholesterol.

7-Dehydrocholesterol (7-DHC) is widely present in various organisms and is an important precursor of vitamin D3. Despite significant improvements in the biosynthesis of 7-DHC, it remains insufficient to meet the industrial demands. In this study, we reported high-level production of 7-DHC in an industrial Saccharomyces cerevisiae leveraging subcellular organelles. Initially, the copy numbers of DHCR24 were increased in combination with sterol transcriptional factor engineering and rebalanced the redox power of the strain. Subsequently, the effects of compartmentalizing the post-squalene pathway in peroxisomes were validated by assembling various pathway modules in this organelle. Furthermore, several peroxisomes engineering was conducted to enhance the production of 7-DHC. Utilizing the peroxisome as a vessel for partial post-squalene pathways, the potential of yeast for 7-dehydrocholesterol production was demonstrated by achieving a 26-fold increase over the initial production level. 7-DHC titer reached 640.77 mg/L in shake flasks and 4.28 g/L in a 10 L bench-top fermentor, the highest titer ever reported. The present work lays solid foundation for large-scale and cost-effective production of 7-DHC for practical applications.

Advancements in gradient bone scaffolds: enhancing bone regeneration in the treatment of various bone disorders.

Bone scaffolds are widely employed for treating various bone disorders, including defects, fractures, and accidents. Gradient bone scaffolds present a promising approach by incorporating gradients in shape, porosity, density, and other properties, mimicking the natural human body structure. This design offers several advantages over traditional scaffolds. A key advantage is the enhanced matching of human tissue properties, facilitating cell adhesion and migration. Furthermore, the gradient structure fosters a smooth transition between scaffold and surrounding tissue, minimizing the risk of inflammation or rejection. Mechanical stability is also improved, providing better support for bone regeneration. Additionally, gradient bone scaffolds can integrate drug delivery systems, enabling controlled release of drugs or growth factors to promote specific cellular activities during the healing process. This comprehensive review examines the design aspects of gradient bone scaffolds, encompassing structure and drug delivery capabilities. By optimizing the scaffold's inherent advantages through gradient design, bone regeneration outcomes can be improved. The insights presented in this article contribute to the academic understanding of gradient bone scaffolds and their applications in bone tissue engineering.

Bimetallic H2 Addition and Intramolecular Caryl-H Activation Mediated by an Iron-Zinc Hydride.

Heteronuclear Fe(µ-H)Zn hydride Cp*Fe(1,2-Cy2PC6H4)HZnEt (3) undergoes reversible intramolecular Caryl-H reductive elimination through coupling of the cyclometalated phosphinoaryl ligand and the hydride, giving rise to a formal Fe(0)-Zn(II) species. Addition of CO intercepts this equilibrium, affording Cp*(Cy2PPh)(CO)Fe-ZnEt that features a dative Fe-Zn bond. Significantly, this system achieves bimetallic H2 addition, as demonstrated by the transformation of the monohydride Fe(µ-H)Zn to a deuterated dihydride Fe-(µ-D)2-Zn upon reaction with D2.

A Large-Scale Network Construction and Lightweighting Method for Point Cloud Semantic Segmentation.

To significantly enhance the performance of point cloud semantic segmentation, this manuscript presents a novel method for constructing large-scale networks and offers an effective lightweighting technique. First, a latent point feature processing (LPFP) module is utilized to interconnect base networks such as PointNet++ and Point Transformer. This intermediate module serves both as a feature information transfer and a ground truth supervision function. Furthermore, in order to alleviate the increase in computational costs brought by constructing large-scale networks and better adapt to the demand for terminal deployment, a novel point cloud lightweighting method for semantic segmentation network (PCLN) is proposed to compress the network by transferring multidimensional feature information of large-scale networks. Specifically, at different stages of the large-scale network, the structure and attention information of the point features are selectively transferred to guide the compressed network to train in the direction of the large-scale network. This paper also solves the problem of representing global structure information of large-scale point clouds through feature sampling and aggregation. Extensive experiments on public datasets and real-world data demonstrate that the proposed method can significantly improve the performance of different base networks and outperform the state-of-the-art.

Acute kidney injury prediction model utility in premature myocardial infarction.

The incidence of premature myocardial infarction (PMI) has been rising and acute kidney injury (AKI) occurring in PMI patients severely impacts prognosis. This study aimed to develop and validate a prediction model for AKI specific to PMI patients. The MIMIC-Ⅲ-CV and MIMIC-Ⅳ databases were utilized for model derivation of PMI patients. Single-center data served for external validation. There were 571 and 182 AKI patients in the training set (n = 937) and external validation set (n = 292) cohorts, respectively. Finally, a 7-variable model consisting of: Sequential Organ Failure Assessment (SOFA) score, coronary artery bypass grafting (CABG), ICU stay time, loop diuretics, estimated glomerular filtration rate (eGFR) HCO3- and Albumin was developed, achieving an AUC of 0.85 (95% CI: 0.83-0.88) in the training set. External validation also confirmed model robustness. This model may assist clinicians in the early identification of patients at elevated risk for PMI. Further validation is warranted before clinical application.

Catalytic hydrogenation of olefins by a multifunctional molybdenum-sulfur complex.

Exploration of molybdenum complexes as homogeneous hydrogenation catalysts has garnered significant attention, but hydrogenation of unactivated olefins under mild conditions are scarce. Here, we report the synthesis of a molybdenum complex, [Cp*Mo(Ph2PC6H4S-CH = CH2)(Py)]+ (2), which exhibits intriguing reactivity toward C2H2 and H2 under ambient pressure. This vinylthioether complex showcases efficient catalytic activity in the hydrogenation of various aromatic and aliphatic alkenes, demonstrating a broad substrate scope without the need for any additives. The catalytic pathway involves an uncommon oxidative addition of H2 to the cationic Mo(II) center, resulting in a Mo(IV) dihydride intermediate. Moreover, complex 2 also shows catalytic activity toward C2H2, leading to the production of polyacetylene and the extension of the vinylthioether ligand into a pendant triene chain.

Relationship between social participation and life satisfaction in community-dwelling older adults: Multiple mediating roles of depression and cognitive function.

BACKGROUND: Numerous studies have explored the relationship between social participation, depression, cognitive function, and life satisfaction in community-dwelling older adults. However, the results of these studies were not consistent. Therefore, the in-depth excavation of the complex relationship mechanism between these four variables is limited. This study aims to explore whether depression and cognitive function act as the multiple mediators between social participation and life satisfaction in community-dwelling older adults. METHODS: This study used the meta-analytic structural equation modeling (MASEM) approach. Six databases were comprehensively searched to investigate the relationship between social participation, depression, cognitive function, and life satisfaction in community-dwelling older adults from inception to March 1, 2023. RESULTS: The analysis included 50 articles that reported 66 effect sizes (N = 161,854). The MASEM found the relationship between social participation and life satisfaction was mediated by depression [ß = 0.085, 95 % CI (0.053, 0.126)] and by cognitive function [ß = 0.015, 95 % CI (0.002, 0.033)], respectively. Depression and cognitive function also played multiple mediating roles between social participation and life satisfaction in community-dwelling older adults [ß = 0.005, 95 % CI (0.001, 0.012)]. CONCLUSIONS: There was not only a direct association between social participation and life satisfaction, but also an association through multiple mediating roles of depression and cognitive function in community-dwelling older adults. In the process of using diverse interventions to promote social participation in community-dwelling older adults, more attention should be paid to their psychological status and cognitive function to eliminate intrinsic barriers so as to improve life satisfaction effectively.

Design of in vitro biomimetic experimental system and simulation analysis for transvascular transport of nano-preparation.

Recently, the enhanced penetration and retention (EPR) effect of nano-preparations has been questioned. Whether the vascular endothelial cell gap (VECG) is the main transport pathway of nano-preparations has become a hot issue at present. Therefore, we propose an in vitro biomimetic experimental system that demonstrates the transvascular transport of nano-preparation. Based on the tumor growth process, the experimental system was used to simulate the change process of abnormal factors (vascular endothelial cell gap and interstitial fluid pressure (IFP)) in the tumor microenvironment. The influence of change in the abnormal factors on the enhanced penetration and retention effect of nano-preparation was explored, and simulation verification was performed. The results show that when the interstitial fluid pressure is close to the vascular fluid pressure (VFP), the transport of nano-preparation is obstructed, resulting in the disappearance of enhanced penetration and retention effect of the nano-preparation. This indicates that the pressure gradient between vascular fluid pressure and interstitial fluid pressure determines whether the enhanced penetration and retention effect of nano-preparations can exist.

Transformation of Acetylene to Ethenylidene, Carbene, Acetylide, Vinyl, and Olefin Groups with Cp*Fe(1,2-Cy2PC6H4S).

Tautomerization of C2H2 at half-sandwich compound Cp*Fe(1,2-Cy2PC6H4S) exclusively produces an iron ethenylidene, Cp*Fe(=C=CH2)(1,2-Cy2PC6H4S) (2). Protonation of the ethenylidene causes nucleophilic attack of the Cα by sulfur, affording a sulfur-tethered carbene complex, [Cp*Fe=C(CH3)SC6H4PCy2]+ (3+). This Fischer-type carbene complex undergoes an unusual isomerization by migrating a hydrogen atom from the ß-CH3 group to the α-C, leading to the formation of an olefin complex [Cp*Fe(η4-CH=CH2SC6H4PCy2]+ (4+). Compound 2 also displays diverse redox reactivities. It transforms to a neutral acetylide ferric complex (5) when reacting with free radical scavengers and to a cationic vinyl complex [Cp*Fe(η3-C(=CH2)SC6H4PCy2]+ (6+) upon 1e- oxidation. The interconversion between the vinyl and acetylide complexes can be realized through protonation/deprotonation reactions.

Electrocatalytic Interconversions of CO2 and Formate on a Versatile Iron-Thiolate Platform.

Exploring bidirectional CO2/HCO2- catalysis holds significant potential in constructing integrated (photo)electrochemical formate fuel cells for energy storage and applications. Herein, we report selective CO2/HCO2- electrochemical interconversion by exploiting the flexible coordination modes and rich redox properties of a versatile iron-thiolate platform, Cp*Fe(II)L (L = 1,2-Ph2PC6H4S-). Upon oxidation, this iron complex undergoes formate binding to generate a diferric formate complex, [(L-)2Fe(III)(µ-HCO2)Fe(III)]+, which exhibits remarkable electrocatalytic performance for the HCO2--to-CO2 transformation with a maximum turnover frequency (TOFmax) ∼103 s-1 and a Faraday efficiency (FE) ∼92(±4)%. Conversely, this iron system also allows for reduction at -1.85 V (vs Fc+/0) and exhibits an impressive FE ∼93 (±3)% for the CO2-to-HCO2- conversion. Mechanism studies revealed that the HCO2--to-CO2 electrocatalysis passes through dicationic [(L2)-•Fe(III)(µ-HCO2)Fe(III)]2+ generated by unconventional oxidation of the diferric formate species taking place at ligand L, while the CO2-to-HCO2- reduction involves a critical intermediate of [Fe(II)-H]- that was independently synthesized and structurally characterized.