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1.
J Environ Manage ; 370: 122547, 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39299117

ABSTRACT

To improve denitrification efficiency of microalgal-bacterial aggregates (MABAs) when treating low carbon to nitrogen (C/N) ratio wastewater, CK (the biological control), C1 (untreated corncobs), C2 (alkali-treated corncobs), CFe1 (C1 loaded iron nanoparticles) and CFe2 (C2 loaded iron nanoparticles) five groups of experiments were installed under artificial light (1600 lm). After 36 h of experiment, NO3--N was almost completely converted in CFe1 following by CFe2 when the initial concentration was 60.1 mg/L, whose NO3--N conversion rates were 6.2 and 3.4 times faster than the CK group, respectively. The result showed that the corncobs-loaded iron nanoparticles (CFe1, CFe2) had the potential to promote denitrification process and the CFe1 was more effective. Meanwhile, the CFe1 and CFe2 resulted in a decreased content in extracellular polymeric substances (EPS) secretion because iron nanoparticles (Fes) promoted electron transport and alleviated the nitrate stress. Moreover, the electrochemical analysis of EPS showed that the corncobs and corncobs-loaded iron nanoparticles improved the electron transport rate and redox active substances production. The increase in electron transport activity (ETSA), adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide (NADH) also indicated that the CFe1 and CFe2 promoted microbial metabolic activity and the electron transport rate in MABAs. In addition, the CFe1 group enhanced the enrichment of Proteobacteria, Patescibacteria, Chlorophyta and Ignavibacteriae, which was contributed to the nitrogen removal performance of MABAs. In summary, the enhancement mechanism of corncobs-loaded iron nanoparticles on denitrification process of MABAs was depicted through EPS secretion, electrochemical characteristics, microbial metabolic activity and microbial community. The article provides a viable program for enhancing the denitrification performance of MABAs when treating low C/N wastewater.

2.
J Adv Res ; 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39299605

ABSTRACT

OBJECTIVES: This study aims to develop a robust predictive model for survival in AML patients undergoing allo-HSCT. METHODS: It was performed a retrospective analysis of 336 AML patients who underwent allo-HSCT at Peking University First Hospital between September 2003 and March 2023. Univariable and multivariable Cox regression analyses were conducted to determine hazard ratios (HR) for overall survival. A predictive model was developed based on multivariable analysis results. Internal validation was carried out through bootstrap resampling, and the model's performance was assessed using the Concordance Index (C-index), Receiver Operating Characteristics (ROC) curve, calibration plots, and Decision Curve Analysis (DCA). RESULTS: Our prognostic model, which includes age, disease stage, donor/recipient gender, mononuclear cell counts, and the Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI), effectively stratified patients into low-risk and high-risk groups. The two groups showed significant differences in overall survival (P<0.0001), disease-free survival (P<0.0001), non-relapse mortality (NRM) (P<0.0001), and relapse rates (P=0.08). The model achieved a C-index of 0.71. Calibration plots and DCA confirmed strong alignment between predicted and observed outcomes. Subgroup analysis revealed that overall survival was significantly lower in the high-risk group compared to the low-risk group in both measurable residual disease (MRD) negative and MRD positive subgroups (P=0.015 for both). CONCLUSION: The developed prognostic model, which integrates comprehensive disease and patient characteristics, enhances risk stratification for AML patients undergoing allo-HSCT. This model effectively stratifies risk in both MRD-negative and MRD-positive subgroups and may facilitate more informed MRD-based treatment decisions.

4.
Small ; : e2405819, 2024 Sep 16.
Article in English | MEDLINE | ID: mdl-39279397

ABSTRACT

Phase engineering is an effective strategy for modulating the electronic structure and electron transfer mobility of cobalt selenide (CoSe2) with remarkable sodium storage. Nevertheless, it remains challenging to improve fast-charging and cycling performance. Herein, a heterointerface coupling induces phase transformation from cubic CoSe2 to orthorhombic CoSe2 accompanied by the formation of MoSe2 to construct a CoSe2/MoSe2 heterostructure decorated with N-doped carbon layer on a 3D graphene foam (CoSe2/MoSe2@NC/GF). The incorporated Mo cations in the bridged o-CoSe2/MoSe2 not only act an electron donor to regulate charge-spin configurations with more active electronic states but also trigger the upshift of d/p band centers and a decreased ∆d-p band center gap, which greatly enhances ion adsorption capability and lowers the ion diffusion barrier. As expected, the CoSe2/MoSe2@NC/GF anode demonstrates a high-rate capability of 447 mAh g-1 at 2 A g-1 and an excellent cyclability of 298 mAh g-1 at 1 A g-1 over 1000 cycles. The work deepens the understanding of the elaborate construction of heterostructured electrodes for high-performance SIBs.

5.
Nat Commun ; 15(1): 8015, 2024 Sep 13.
Article in English | MEDLINE | ID: mdl-39271695

ABSTRACT

Realizing an efficient turnover frequency in the acidic oxygen evolution reaction by modifying the reaction configuration is crucial in designing high-performance single-atom catalysts. Here, we report a "single atom-double site" concept, which involves an activatable inert manganese atom redox chemistry in a single-atom Ru-Mn dual-site platform with tunnel Ni ions as the trigger. In contrast to conventional single-atom catalysts, the proposed configuration allows direct intramolecular oxygen coupling driven by the Ni ions intercalation effect, bypassing the secondary deprotonation step instead of the kinetically sluggish adsorbate evolution mechanism. The strong bonding of Ni ions activates the inert manganese terminal groups and inhibits the cross-site disproportionation process inherent in the Mn scaffolding, which is crucial to ensure the dual-site platform. As a result, the single-atom Ru-Ni-Mn octahedral molecular sieves catalyst delivers a low overpotential, adequate mass activity and good stability.

6.
Front Immunol ; 15: 1443885, 2024.
Article in English | MEDLINE | ID: mdl-39229276

ABSTRACT

Background: Inflammaging, an immune status characterized by a sustained increase in pro-inflammatory markers and a decline in anti-inflammatory mechanisms, is a critical risk factor in the development of sarcopenia. Landscapes of the causal relationships between immunity and sarcopenia are needed to understand the mechanism of sarcopenia and provide novel treatments comprehensively. Methods: We used Mendelian Randomization (MR) as the basic method in this study. By setting immune proteins, immune cells, and sarcopenia as exposures and outcomes alternatively, and then combining them in different directions, we potentially estimated their causal relationships and directions and subsequently mapped the comprehensive causal landscape based on this information efficiently. To further understand the network, we developed a method based on rank-sums to integrate multiple algorithms and identify the key immune cells and proteins. Results: More than 1,000 causal relationships were identified between immune cell phenotypes, proteins, and sarcopenia traits (p < 0.05), and the causal maps of these linkages were established. In the threshold of FDR < 0.05, hundreds of causal linkages were still significant. The final comprehensive map included 13 immune cell phenotypes and 8 immune proteins. The star factors in the final map included EM CD8br %CD8br, EM DN (CD4- CD8-) %DN, SIRT2, and so on. Conclusion: By reading the landscapes in this study, we may not only find the factors and the pathways that have been reported and proven but also identify multiple novel immunity cell phenotypes and proteins with enriched upstream and downstream pathways.


Subject(s)
Sarcopenia , Humans , Sarcopenia/immunology , Mendelian Randomization Analysis , Immunity/genetics
7.
J Colloid Interface Sci ; 678(Pt A): 1087-1098, 2024 Sep 02.
Article in English | MEDLINE | ID: mdl-39241470

ABSTRACT

Prussian blue analogs (PBAs) have attracted extensive attention in the field of aqueous organic degradation due to the tremendous potential for peroxydisulfate (PDS) activation. However, the relationship between the d-band center of the catalyst and the activation behavior of PDS remained largely unexplored. Herein, a series of Fe-Co PBAs-based catalysts with different Fe/Co ratios (Fe-Co PBAs-1 = 1: 0.52; Fe-Co PBAs-2 = 1: 1.21, and Fe-Co PBAs-3 = 1: 1.48) have been prepared by a facile hydrothermal procedure and subsequent acid treatment (Fe-Co PBAs-xH). The as-prepared Fe-Co PBAs-xH exhibited superior PDS activation performance and excellent recyclability in the degradation of methylene blue (MB). Density functional theory calculations revealed that the electron-occupied state of the Fe-Co PBAs was shifted to the Fermi level, indicating a strong interaction and easier electron transfer. Moreover, the d-band center of Fe-Co PBAs was upshifted relative to that of Fe PBAs, suggesting easier adsorption of MB and PDS, which was beneficial to enhancing catalytic activation and subsequent dissociation. Radicals such as •OH, 1O2, O2•-, and SO4•- were determined by the radical quenching experiment and electron paramagnetic resonance (EPR) testing in the Fe-Co PBAs-3H/PDS system, and the order of MB degradation by the free active radical is •OH > 1O2 > O2•- > SO4•-. The degradation pathway and potential ecotoxicity of MB and its intermediates were also studied. This work can provide new insights to construct the efficient catalysts for the activation of PDS and the degradation of organic pollutants.

8.
Lipids Health Dis ; 23(1): 283, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39232765

ABSTRACT

BACKGROUND: Sepsis-induced cardiomyopathy (SICM) is a common and life-threatening complication of sepsis, significantly contributing to elevated mortality. This study aimed to identify crucial indicators for the prompt and early assessment of SICM. METHODS: Patients diagnosed with sepsis or SICM within 24 h of intensive care unit (ICU) admission were enrolled in this prospective observational study. Patients were assigned to the training set, validation set and external test set. The primary endpoint was 7-day ICU mortality, and the secondary endpoint was 28-day ICU mortality. Three machine learning algorithms were utilized to identify relevant indicators for diagnosing SICM, incorporating 64 indicators including serum biomarkers associated with cardiac, renal, and liver function, lipid metabolism, coagulation, and inflammation. Internal and external validations were performed on the screening results. Patients were then stratified based on the cut-off value of the most diagnostically effective biomarker identified, and their prognostic outcomes were observed and analyzed. RESULTS: A total of 270 patients were included in the training and validation set, and 52 patients were included in the external test set. Age, sex, and comorbidities did not significantly differ between the sepsis and SICM groups (P > 0.05). The support vector machine (SVM) algorithm identified six indicators with an accuracy of 84.5%, the random forest (RF) algorithm identified six indicators with an accuracy of 81.9%, and the logistic regression (LR) algorithm screened out seven indicators. Following rigorous selection, a diagnostic model for sepsis-induced cardiomyopathy was established based on heart-type fatty acid binding protein (H-FABP) (OR 1.308, 95% CI 1.170-1.462, P < 0.001) and retinol-binding protein (RBP) (OR 1.020, 95% CI 1.006-1.034, P < 0.05). H-FABP alone exhibited the highest diagnostic performance in both the internal (AUROC 0.689, P < 0.05) and external sets (AUROC 0.845, P < 0.05). Patients with SICM were further stratified based on an H-FABP diagnostic cut-off value of 8.335 ng/mL. Kaplan-Meier curve analysis demonstrated that elevated H-FABP levels at admission were associated with higher 7-day ICU mortality in patients with SICM (P < 0.05). CONCLUSIONS: This study revealed that H-FABP concentrations measured within 24 h of patient admission could serve as a crucial biomarker for the early and rapid diagnosis and short-term prognostic evaluation of SICM.


Subject(s)
Biomarkers , Cardiomyopathies , Fatty Acid-Binding Proteins , Sepsis , Humans , Male , Female , Biomarkers/blood , Cardiomyopathies/blood , Cardiomyopathies/diagnosis , Cardiomyopathies/etiology , Sepsis/blood , Sepsis/complications , Sepsis/diagnosis , Middle Aged , Prospective Studies , Fatty Acid-Binding Proteins/blood , Aged , Fatty Acid Binding Protein 3/blood , Intensive Care Units , Prognosis , ROC Curve , Support Vector Machine
9.
Cancers (Basel) ; 16(17)2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39272886

ABSTRACT

As a crucial amino acid, glutamine can provide the nitrogen and carbon sources needed to support cancer cell proliferation, invasion, and metastasis. Interestingly, different types of breast cancer have different dependences on glutamine. This research shows that basal-like breast cancer depends on glutamine, while the other types of breast cancer may be more dependent on glucose. Glutamine transporter ASCT2 is highly expressed in various cancers and significantly promotes the growth of breast cancer. However, the key regulatory mechanism of ASCT2 in promoting basal-like breast cancer progression remains unclear. Our research demonstrates the significant change in fatty acid levels caused by ASCT2, which may be a key factor in glutamine sensitivity. This phenomenon results from the mutual activation between ASCT2-mediated glutamine transport and lipid metabolism via the nuclear receptor PPARα. ASCT2 cooperatively promoted PPARα expression, leading to the upregulation of lipid metabolism. Moreover, we also found that C118P could inhibit lipid metabolism by targeting ASCT2. More importantly, this research identifies a potential avenue of evidence for the prevention and early intervention of basal-like breast cancer by blocking the glutamine-lipid feedback loop.

10.
Angew Chem Int Ed Engl ; : e202414533, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39248630

ABSTRACT

Organic radicals based dynamic covalent chemistry is promising in preparing stimuli-responsive chromic materials, due to their simplicity of dissociation/association, accompanied with distinct color changes during the process. However, suitable organic radicals for dynamic covalent chemistry have not been widely explored yet. Herein, a series of oxindolyl-based mono-radicals (OxRs) with different substituents were successfully synthesized and studied systematically as potential building blocks for stimuli-responsive chromic materials. These OxRs would dimerize spontaneously to form their corresponding dimers. The structures of dimers were unambiguously confirmed through low-temperature 1H-NMR and single-crystal X-ray diffraction analyses. Dynamic interconversion between monomers and dimers was achieved by reversible cleavage and recovery of the σ-bond upon soft external stimuli (temperature, pressure, and solvent polarity), accompanied by significant color changes. It is interesting that the stability of the mono-radical could be tuned through changing different substituents, and consequently altering the bond dissociation energy of the dynamic covalent bond between monomers. These new OxRs characterized by appreciable properties are entitled to more opportunities in developing mechanochromic and thermochromic materials, where their responsiveness to stimuli can be readily controlled by the substituents adhered.

11.
J Am Chem Soc ; 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39315945

ABSTRACT

Peri-acenes are valuable models for zigzag-edged graphene nanoribbons, but their synthesis poses significant challenges. In this study, stable derivatives of peri-pentacene (Peri-P) and peri-hexacene (Peri-H) were synthesized. Through kinetic blocking and a synergistic captodative effect, both compounds displayed remarkable stability under ambient air and light conditions. They show significant diradical character (y0), with y0 = 75.4% for Peri-P and y0 = 90.7% for Peri-H, alongside narrow singlet-triplet energy gaps of -1.68 ± 0.04 and -1.28 ± 0.02 kcal/mol, respectively. The structure of Peri-H was confirmed by X-ray crystallography, with bond-length analysis and theoretical calculations indicating a dominant structure featuring five aromatic sextet rings. Their optical and electrochemical properties were also studied and compared to those of smaller peri-acenes.

12.
Arch Orthop Trauma Surg ; 144(8): 3291-3301, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39105842

ABSTRACT

INTRODUCTION: Effective tools to evaluate bone quality preoperatively are scarce and the standard method to determine bone quality requires an invasive biopsy. A non-invasive, and preoperatively available method for bone quality assessment would be of clinical value. The purpose of this study is to investigate the associations of bone formation marker, serum bone alkaline phosphatase (BAP), and bone resorption marker, urine collagen cross-linked N-telopeptide (uNTX) to volumetric bone mineral density (vBMD), fluorescent advanced glycation endproducts (fAGEs) and bone microstructure. MATERIALS AND METHODS: A cross-secional analysis using prospective data of patients undergoing lumbar spinal fusion was performed. BAP and uNTX were preoperatively collected. Quantitative computed tomography (QCT) was performed at the lumbar spine (vBMD ≤ 120 mg/cm3 osteopenic/osteoporotic). Bone biopsies from the posterior superior iliac spine were obtained and evaluated with multiphoton fluorescence microscopy for fAGEs and microcomputed tomography (µCT) for bone microarchitecture. Correlations between BAP/uNTX to vBMD, fAGEs and µCT parameters were assessed with Spearman's ρ. Receiver operating characteristic (ROC) analysis evaluated BAP and uNTX as predictors for osteopenia/osteoporosis. Multivariable linear regression models adjusting for age, sex, BMI, race and diabetes mellitus determined associations between BAP/uNTX and fAGEs. RESULTS: 127 prospectively enrolled patients (50.4% female, 62.5 years, BMI 28.7 kg/m2) were analyzed. uNTX (ρ=-0.331,p < 0.005) and BAP (ρ=-0.245,p < 0.025) decreased with cortical fAGEs, and uNTX (ρ=-0.380,p < 0.001) decreased with trabecular fAGEs. BAP and uNTX revealed no significant correlation with vBMD. ROC analysis for BAP and uNTX discriminated osteopenia/osteoporosis with AUC of 0.477 and 0.561, respectively. In the multivariable analysis, uNTX decreased with increasing trabecular fAGEs after adjusting for covariates (ß = 0.923;p = 0.031). CONCLUSION: This study demonstrated an inverse association of bone turnover markers and fAGEs. Both uNTX and BAP could not predict osteopenia/osteoporosis in the spine. uNTX reflects collagen characteristics and might have a complementary role to vBMD, as a non-invasive tool for bone quality assessment in spine surgery.


Subject(s)
Biomarkers , Bone Density , Bone Remodeling , Glycation End Products, Advanced , Lumbar Vertebrae , Spinal Fusion , Humans , Female , Male , Prospective Studies , Lumbar Vertebrae/diagnostic imaging , Middle Aged , Aged , Biomarkers/blood , Bone Remodeling/physiology , Cross-Sectional Studies , Alkaline Phosphatase/blood , Peptides/blood , Osteoporosis , Collagen Type I/urine , Collagen Type I/blood , Bone Diseases, Metabolic/diagnostic imaging
13.
Angew Chem Int Ed Engl ; : e202412077, 2024 Aug 07.
Article in English | MEDLINE | ID: mdl-39109496

ABSTRACT

Sub-nanoclusters with ultra-small particle sizes are particularly significant to create advanced energy storage materials. Herein, Sn sub-nanoclusters encapsulated in nitrogen-doped multichannel carbon matrix (denoted as Sn-SCs@MCNF) are designed by a facile and controllable route as flexible anode for high-performance potassium ion batteries (PIBs). The uniformly dispersed Sn sub-nanoclusters in multichannel carbon matrix can be precisely identified, which ensure us to clarify the size influence on the electrochemical performance. The sub-nanoscale effect of Sn-SCs@MCNF restrains electrode pulverization and enhances the K+ diffusion kinetics, leading to the superior cycling stability and rate performance. As freestanding anode in PIBs, Sn-SCs@MCNF manifests superior K+ storage properties, such as exceptional cycling stability ( around 331 mAh g-1 after 150 cycles at 100 mA g-1) and rate capability. Especially, the Sn-SCs@MCNF||KFe[Fe(CN)6] full cell demonstrates impressive reversible capacity of around 167 mAh g-1 at 0.4 A g-1 even after 200 cycles. Theoretical calculations clarify that the ultrafine Sn sub-nanoclusters are beneficial for electron transfer and contribute to the lower energy barriers of the intermediates, thereby resulting in promising electrochemical performance. Comprehensive investigation for the intrinsic K+ storage process of Sn-SCs@MCNF is revealed by in situ analysis. This work provides vital guidance to design sub-nanoscale functional materials for high-performance energy-storage devices.

14.
Genome Biol ; 25(1): 232, 2024 Aug 28.
Article in English | MEDLINE | ID: mdl-39198826

ABSTRACT

BACKGROUND: The relationship between human gut microbiota and high-altitude hypoxia acclimatization remains highly controversial. This stems primarily from uncertainties regarding both the potential temporal changes in the microbiota under such conditions and the existence of any dominant or core bacteria that may assist in host acclimatization. RESULTS: To address these issues, and to control for variables commonly present in previous studies which significantly impact the results obtained, namely genetic background, ethnicity, lifestyle, and diet, we conducted a 108-day longitudinal study on the same cohort comprising 45 healthy Han adults who traveled from lowland Chongqing, 243 masl, to high-altitude plateau Lhasa, Xizang, 3658 masl, and back. Using shotgun metagenomic profiling, we study temporal changes in gut microbiota composition at different timepoints. The results show a significant reduction in the species and functional diversity of the gut microbiota, along with a marked increase in functional redundancy. These changes are primarily driven by the overgrowth of Blautia A, a genus that is also abundant in six independent Han cohorts with long-term duration in lower hypoxia environment in Shigatse, Xizang, at 4700 masl. Further animal experiments indicate that Blautia A-fed mice exhibit enhanced intestinal health and a better acclimatization phenotype to sustained hypoxic stress. CONCLUSIONS: Our study underscores the importance of Blautia A species in the gut microbiota's rapid response to high-altitude hypoxia and its potential role in maintaining intestinal health and aiding host adaptation to extreme environments, likely via anti-inflammation and intestinal barrier protection.


Subject(s)
Acclimatization , Altitude , Gastrointestinal Microbiome , Hypoxia , Humans , Animals , Adult , Male , Hypoxia/genetics , Mice , Female , Longitudinal Studies , Altitude Sickness/microbiology , Altitude Sickness/genetics , Middle Aged
15.
Angew Chem Int Ed Engl ; : e202414650, 2024 Aug 29.
Article in English | MEDLINE | ID: mdl-39206502

ABSTRACT

Investigating the formation and transformation mechanisms of spiral-concave crystals holds significant potential for advancing innovative material design and comprehension. We examined the kinetics-controlled nucleation and growth mechanisms of Prussian Blue crystals with spiral concave structures, and constructed a detailed crystal growth phase diagram. The spiral-concave hexacyanoferrate (SC-HCF) crystals, characterized by high-density surface steps and a low stress-strain architecture, exhibit enhanced activity due to their facile interaction with reactants. Notably, the coordination environment of SC-HCF can be precisely modulated by the introduction of diverse metals. Utilizing X-ray absorption fine structure spectroscopy and in-situ ultraviolet-visible spectroscopy, we elucidated the formation mechanism of SC-HCF to Co-HCF facilitated by oriented adsorption-ion exchange (OA-IE) process. Both experimental data, and density functional theory confirm that Co-HCF possesses an optimized energy band structure, capable of adjusting the local electronic environment and enhancing the performance of the oxygen evolution reaction. This work not only elucidates the formation mechanism and coordination regulation for rich steps HCF, but also offers a novel perspective for constructing nanocrystals with intricate spiral-concave structures.

16.
Nat Immunol ; 25(9): 1623-1636, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39107403

ABSTRACT

Targeting tumor-infiltrating regulatory T (TI-Treg) cells is a potential strategy for cancer therapy. The ATPase p97 in complex with cofactors (such as Npl4) has been investigated as an antitumor drug target; however, it is unclear whether p97 has a function in immune cells or immunotherapy. Here we show that thonzonium bromide is an inhibitor of the interaction of p97 and Npl4 and that this p97-Npl4 complex has a critical function in TI-Treg cells. Thonzonium bromide boosts antitumor immunity without affecting peripheral Treg cell homeostasis. The p97-Npl4 complex bridges Stat3 with E3 ligases PDLIM2 and PDLIM5, thereby promoting Stat3 degradation and enabling TI-Treg cell development. Collectively, this work shows an important role for the p97-Npl4 complex in controlling Treg-TH17 cell balance in tumors and identifies possible targets for immunotherapy.


Subject(s)
T-Lymphocytes, Regulatory , T-Lymphocytes, Regulatory/immunology , Animals , Mice , Humans , Mice, Inbred C57BL , STAT3 Transcription Factor/metabolism , Nuclear Proteins/metabolism , Neoplasms/immunology , Cell Line, Tumor , Th17 Cells/immunology , Immunotherapy/methods , LIM Domain Proteins/metabolism , Adenosine Triphosphatases/metabolism , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Female
17.
Langmuir ; 40(37): 19506-19516, 2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39205649

ABSTRACT

The efficacy and structural evolution of Mo-doped titania nanoparticles (MTNPs) as advanced photocatalysts for degrading methyl blue (MB) are investigated by X-ray absorption spectroscopy (XAS). The 3 wt % MTNP, characterized by uniform size and anatase structure, exhibits higher efficiency. The spectral analyses unveiled structural variations in the TiO6 octahedral structure and revealed an active site of the distorted square pyramidal structure symmetry (C4v). The in situ XAS spectra illustrate that MTNPs, particularly at 3 wt % doping, effectively enhanced the hole carriers in Ti 3d orbitals with a charge transfer to Mo 4d orbitals and impeded electron-hole pair merging, significantly enhancing the photodegradation under light illumination. This study deepens our understanding of the crucial role of Mo doping in optimizing TiO2 nanoparticle performance for efficient environmental remediation, showcasing the potential of MTNPs as sustainable photocatalytic materials.

18.
Int J Mol Sci ; 25(16)2024 Aug 15.
Article in English | MEDLINE | ID: mdl-39201563

ABSTRACT

Nitric oxide (NO) has been firmly established as a key signaling molecule in plants, playing a significant role in regulating growth, development and stress responses. Given the imperative of sustainable agriculture and the urgent need to meet the escalating global demand for food, it is imperative to safeguard crop plants from the effects of climate fluctuations. Plants respond to environmental challenges by producing redox molecules, including reactive oxygen species (ROS) and reactive nitrogen species (RNS), which regulate cellular, physiological, and molecular processes. Nitric oxide (NO) plays a crucial role in plant stress tolerance, acting as a signaling molecule or free radical. NO is involved in various developmental processes in plants through diverse mechanisms. Exogenous NO supplementation can alleviate the toxicity of abiotic stresses and enhance plant resistance. In this review we summarize the studies regarding the production of NO in peroxisomes, and how its molecule and its derived products, (ONOO-) and S-nitrosoglutathione (GSNO) affect ROS metabolism in peroxisomes. Peroxisomal antioxidant enzymes including catalase (CAT), are key targets of NO-mediated post-translational modification (PTM) highlighting the dynamic metabolism of ROS and RNS in peroxisomes.


Subject(s)
Nitric Oxide , Peroxisomes , Protein Processing, Post-Translational , Reactive Nitrogen Species , Reactive Oxygen Species , Peroxisomes/metabolism , Reactive Oxygen Species/metabolism , Nitric Oxide/metabolism , Reactive Nitrogen Species/metabolism , Plants/metabolism
20.
J Am Chem Soc ; 146(33): 23146-23157, 2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39109994

ABSTRACT

The poor durability of Ru-based catalysts limits the practical application in proton exchange membrane water electrolysis (PEMWE). Here, we report that the asymmetric active units in Ru1-xMxO2 (M = Sb, In, and Sn) binary solid solution oxides are constructed by introducing acid-resistant p-block metal sites, breaking the activity and stability limitations of RuO2 in acidic oxygen evolution reaction (OER). Constructing highly asymmetric Ru-O-Sb units with a strong electron delocalization effect significantly shortens the spatial distance between Ru and Sb sites, improving the bonding strength of the overall structure. The unique two-electron redox couples at Sb sites in asymmetric active units trigger additional chemical steps at different OER stages, facilitating continuous proton transfer. The optimized Ru0.8Sb0.2O2 solid solution requires a superlow overpotential of 160 mV at 10 mA cm-2 and a record-breaking stability of 1100 h in an acidic electrolyte. Notably, the scale-prepared Ru0.8Sb0.2O2 achieves efficient PEMWE performance under industrial conditions. General mechanism analysis shows that the enhanced proton transport in the asymmetric Ru-O-M unit provides a new working pathway for acidic OER, breaking the scaling relationship without sacrificing stability.

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