Branched-Chain Amino Acids Deficiency Promotes Diabetic Neuropathic Pain Through Upregulating LAT1 and Inhibiting Kv1.2 Channel.

Diabetic neuropathic pain (DNP), one of the most common complications of diabetes, is characterized by bilateral symmetrical distal limb pain and substantial morbidity. To compare the differences  is aimed at serum metabolite levels between 81 DNP and 73 T2DM patients without neuropathy and found that the levels of branched-chain amino acids (BCAA) are significantly lower in DNP patients than in T2DM patients. In high-fat diet/low-dose streptozotocin (HFD/STZ)-induced T2DM and leptin receptor-deficient diabetic (db/db) mouse models, it is verified that BCAA deficiency aggravated, whereas BCAA supplementation alleviated DNP symptoms. Mechanistically, using a combination of RNA sequencing of mouse dorsal root ganglion (DRG) tissues and label-free quantitative proteomic analysis of cultured cells, it is found that BCAA deficiency activated the expression of L-type amino acid transporter 1 (LAT1) through ATF4, which is reversed by BCAA supplementation. Abnormally upregulated LAT1 reduced Kv1.2 localization to the cell membrane, and inhibited Kv1.2 channels, thereby increasing neuronal excitability and causing neuropathy. Furthermore, intraperitoneal injection of the LAT1 inhibitor, BCH, alleviated DNP symptoms in mice, confirming that BCAA-deficiency-induced LAT1 activation contributes to the onset of DNP. These findings provide fresh insights into the metabolic differences between DNP and T2DM, and the development of approaches for the management of DNP.

An evaluation of the regional heterogeneity of museums' operational efficiency and productivity changes across Chinese provinces.

Museums are critical in safeguarding cultural heritage and cultivating community educational opportunities. This research aims to evaluate operational efficiency (OE), the impact of technological change on total factor productivity change (TFPC), and the regional heterogeneity of museum performance in three regions and 31 provinces across China. To this end, the study employed DEA-SBM and the Malmquist Productivity Index to gauge OE, TFPC, and determinants of TFPC (efficiency change or emerging technologies change) across 31 provinces for 2012-2021. Results reveal that the average OE of the Chinese Museum is 0.8394. It shows a 16.06 % growth potential in the operational efficiency of Chinese Museums. Further, the OE of Chinese Museums declined over the study period from 0.8965 in 2012 to 0.8088 in 2021. Beijing, Fujian, and Hunan are ranked top with a Museum's OE Score of 1. The average MI score of Chinese Museums is 0.9744, and technology change is the main determinant of Decline in productivity change as EC = 0.9992 is greater than TC = 0.9846. The MI of Liaoning, Shanghai, Ningxia, Jiangxi, Chongqing, Sichuan, Guangdong, and Tianjin is over 1, indicating growth in total factor productivity over the study period. The eastern region of China shows higher operational efficiency and total factor productivity scores of museums than the central and western regions. The results of the Kruskal-Wallis test proved that a statistically significant difference exists among different regions of China for the OE, MI, EC, and TC of museums.

Etomidate Combined with Propofol versus Remimazolam for Sedation in Elderly Patients During Gastrointestinal Endoscopy: A Randomized Prospective Clinical Trial.

Purpose: Remimazolam is a novel short-acting benzodiazepine used for sedation and general anesthesia. This study aimed to evaluate the efficacy and safety of remimazolam besylate in elderly patients who underwent diagnostic gastrointestinal endoscopy. Patients and Methods: A total of 120 patients aged 60-75 years were randomly allocated to one of two groups. Remifentanil 0.3µg/kg was used for analgesia. Patients were administered remimazolam besylate 7 mg (R group) or etomidate 0.1 mg/kg combined with 1% propofol 0.5 mg/kg (EP group) for induction, supplemental repeated doses were given as needed. Some time metrics, vital signs, adverse events were evaluated. Patients' Mini-cog score and recovery questionnaires were compared. Results: Compared to the EP group, the induction time was slightly longer in the R group (1.50 VS 1.15 minutes) (P<0.05), the time spent in the post-anesthesia care unit (PACU) was shorter (15.17 VS 17.40 minutes) (P<0.05). Compare with EP group, SBP was lower in R group at T15 and T25 time point, but heart rate was higher in T2, T3, T5 (P< 0.05). The Mini-Cog score was higher after the procedure (2.83 VS 2.58) (P<0.05). The incidence of respiratory adverse events was higher in the EP group than R group (18.3% VS 5.0%, P < 0.05). The most common adverse event in R group was hiccups. The sedation satisfaction rate and degree of amnesia were higher in the R group (66.7% VS 11.7%) (P < 0.05), and the effect on patient's life within 24 hours was lower (12.0% VS 30.5%) (P < 0.05). Conclusion: The safety and efficacy of remimazolam besylate are not inferior to those of etomidate combined with propofol, rendering it a safe option for sedation during gastrointestinal endoscopy in ASA I-II elderly patients, but care should be taken to monitor the occurrence of hiccups.

CREST-UK: Real-world effectiveness, safety and outpatient delivery of CPX-351 for first-line treatment of newly diagnosed therapy-related AML and AML with myelodysplasia-related changes in the UK.

Favourable outcomes with CPX-351 versus conventional 7 + 3 were demonstrated in the pivotal phase III trial in adults aged 60-75 years with newly diagnosed, highrisk/secondary acute myeloid leukaemia (AML). As a complement to the clinical trial and to address important data gaps, the CPX-351 Real-World Effectiveness and SafeTy (CREST-UK; NCT05169307) study evaluated the use of CPX-351 in routine clinical practice in the UK, in 147 patients with newly diagnosed therapy-related AML or AML with myelodysplasia-related changes. Best response of complete remission or complete remission with incomplete platelet or neutrophil recovery was achieved by 53% of evaluable patients. Kaplan-Meier median overall survival (OS) was 12.8 months (95% confidence interval 9.2-15.3). Fifty (34%) patients proceeded to haematopoietic cell transplantation (HCT); median OS landmarked from the HCT date was not reached. There were no new safety concerns with CPX-351 identified in CREST-UK. Patients treated with CPX-351 in the outpatient setting spent an average of 24.4, 16.7, 28.2, and 27.7 fewer days on the ward compared with inpatients during first induction, second induction, first consolidation, and second consolidation, respectively. The results from CREST-UK provide valuable insights into the effectiveness, safety, and outpatient delivery of CPX-351 in routine clinical practice in the UK.

Rare variations within the serine/arginine-rich splicing factor PtoRSZ21 modulate stomatal size to determine drought tolerance in Populus.

Rare variants contribute significantly to the 'missing heritability' of quantitative traits. The genome-wide characteristics of rare variants and their roles in environmental adaptation of woody plants remain unexplored. Utilizing genome-wide rare variant association study (RVAS), expression quantitative trait loci (eQTL) mapping, genetic transformation, and molecular experiments, we explored the impact of rare variants on stomatal morphology and drought adaptation in Populus. Through comparative analysis of five world-wide Populus species, we observed the influence of mutational bias and adaptive selection on the distribution of rare variants. RVAS identified 75 candidate genes correlated with stomatal size (SS)/stomatal density (SD), and a rare haplotype in the promoter of serine/arginine-rich splicing factor PtoRSZ21 emerged as the foremost association signal governing SS. As a positive regulator of drought tolerance, PtoRSZ21 can recruit the core splicing factor PtoU1-70K to regulate alternative splicing (AS) of PtoATG2b (autophagy-related 2). The rare haplotype PtoRSZ21hap2 weakens binding affinity to PtoMYB61, consequently affecting PtoRSZ21 expression and SS, ultimately resulting in differential distribution of Populus accessions in arid and humid climates. This study enhances the understanding of regulatory mechanisms that underlie AS induced by rare variants and might provide targets for drought-tolerant varieties breeding in Populus.

Airway basal stem cells are necessary for the maintenance of functional intraepithelial airway macrophages.

Adult stem cells play a crucial role in tissue homeostasis and repair through multiple mechanisms. In addition to being able to replace aged or damaged cells, stem cells provide signals that contribute to the maintenance and function of neighboring cells. In the lung, airway basal stem cells also produce cytokines and chemokines in response to inhaled irritants, allergens, and pathogens, which affect specific immune cell populations and shape the nature of the immune response. However, direct cell-to-cell signaling through contact between airway basal stem cells and immune cells has not been demonstrated. Recently, a unique population of intraepithelial airway macrophages (IAMs) has been identified in the murine trachea. Here, we demonstrate that IAMs require Notch signaling from airway basal stem cells for maintenance of their differentiated state and function. Furthermore, we demonstrate that Notch signaling between airway basal stem cells and IAMs is required for antigen-induced allergic inflammation only in the trachea where the basal stem cells are located whereas allergic responses in distal lung tissues are preserved consistent with a local circuit linking stem cells to proximate immune cells. Finally, we demonstrate that IAM-like cells are present in human conducting airways and that these cells display Notch activation, mirroring their murine counterparts. Since diverse lung stem cells have recently been identified and localized to specific anatomic niches along the proximodistal axis of the respiratory tree, we hypothesize that the direct functional coupling of local stem cell-mediated regeneration and immune responses permits a compartmentalized inflammatory response.

DriveLLaVA: Human-Level Behavior Decisions via Vision Language Model.

Human-level driving is the ultimate goal of autonomous driving. As the top-level decision-making aspect of autonomous driving, behavior decision establishes short-term driving behavior strategies by evaluating road structures, adhering to traffic rules, and analyzing the intentions of other traffic participants. Existing behavior decisions are primarily implemented based on rule-based methods, exhibiting insufficient generalization capabilities when faced with new and unseen driving scenarios. In this paper, we propose a novel behavior decision method that leverages the inherent generalization and commonsense reasoning abilities of visual language models (VLMs) to learn and simulate the behavior decision process in human driving. We constructed a novel instruction-following dataset containing a large number of image-text instructions paired with corresponding driving behavior labels, to support the learning of the Drive Large Language and Vision Assistant (DriveLLaVA) and enhance the transparency and interpretability of the entire decision process. DriveLLaVA is fine-tuned on this dataset using the Low-Rank Adaptation (LoRA) approach, which efficiently optimizes the model parameter count and significantly reduces training costs. We conducted extensive experiments on a large-scale instruction-following dataset, and compared with state-of-the-art methods, DriveLLaVA demonstrated excellent behavior decision performance. DriveLLaVA is capable of handling various complex driving scenarios, showing strong robustness and generalization abilities.

Towards Robust Decision-Making for Autonomous Highway Driving Based on Safe Reinforcement Learning.

Reinforcement Learning (RL) methods are regarded as effective for designing autonomous driving policies. However, even when RL policies are trained to convergence, ensuring their robust safety remains a challenge, particularly in long-tail data. Therefore, decision-making based on RL must adequately consider potential variations in data distribution. This paper presents a framework for highway autonomous driving decisions that prioritizes both safety and robustness. Utilizing the proposed Replay Buffer Constrained Policy Optimization (RECPO) method, this framework updates RL strategies to maximize rewards while ensuring that the policies always remain within safety constraints. We incorporate importance sampling techniques to collect and store data in a Replay buffer during agent operation, allowing the reutilization of data from old policies for training new policy models, thus mitigating potential catastrophic forgetting. Additionally, we transform the highway autonomous driving decision problem into a Constrained Markov Decision Process (CMDP) and apply our proposed RECPO for training, optimizing highway driving policies. Finally, we deploy our method in the CARLA simulation environment and compare its performance in typical highway scenarios against traditional CPO, current advanced strategies based on Deep Deterministic Policy Gradient (DDPG), and IDM + MOBIL (Intelligent Driver Model and the model for minimizing overall braking induced by lane changes). The results show that our framework significantly enhances model convergence speed, safety, and decision-making stability, achieving a zero-collision rate in highway autonomous driving.

Populus euphratica CPK21 Interacts with NF-YC3 to Enhance Cadmium Tolerance in Arabidopsis.

The toxic metal cadmium (Cd) poses a serious threat to plant growth and human health. Populus euphratica calcium-dependent protein kinase 21 (CPK21) has previously been shown to attenuate Cd toxicity by reducing Cd accumulation, enhancing antioxidant defense and improving water balance in transgenic Arabidopsis. Here, we confirmed a protein-protein interaction between PeCPK21 and Arabidopsis nuclear transcription factor YC3 (AtNF-YC3) by yeast two-hybrid and bimolecular fluorescence complementation assays. AtNF-YC3 was induced by Cd and strongly expressed in PeCPK21-overexpressed plants. Overexpression of AtNF-YC3 in Arabidopsis reduced the Cd inhibition of root length, fresh weight and membrane stability under Cd stress conditions (100 µM, 7 d), suggesting that AtNF-YC3 appears to contribute to the improvement of Cd stress tolerance. AtNF-YC3 improved Cd tolerance by limiting Cd uptake and accumulation, activating antioxidant enzymes and reducing hydrogen peroxide (H2O2) production under Cd stress. We conclude that PeCPK21 interacts with AtNF-YC3 to limit Cd accumulation and enhance the reactive oxygen species (ROS) scavenging system and thereby positively regulate plant adaptation to Cd environments. This study highlights the interaction between PeCPK21 and AtNF-YC3 under Cd stress conditions, which can be utilized to improve Cd tolerance in higher plants.

Prospective and multi-reader evaluation of deep learning reconstruction-based accelerated rectal MRI: image quality, diagnostic performance, and reading time.

OBJECTIVES: To evaluate deep learning reconstruction (DLR)-based accelerated rectal magnetic resonance imaging (MRI) compared with standard MRI. MATERIALS AND METHODS: Patients with biopsy-confirmed rectal adenocarcinoma between November/2022 and May/2023 in a single centre were prospectively enrolled for an intra-individual comparison between standard fast spin-echo (FSEstandard) and DLR-based FSE (FSEDL) sequences. Quantitative and qualitative image quality metrics of the pre-therapeutic MRIs were evaluated in all patients; diagnostic performance and evaluating time for T-staging, N-staging, extramural vascular invasion (EMVI), and mesorectal fascia (MRF) status was further analysed in patients undergoing curative surgery, with histopathologic results as the diagnostic gold standard. RESULTS: A total of 117 patients were enrolled, with 60 patients undergoing curative surgery. FSEDL reduced the acquisition time by 65% than FSEstandard. FSEDL exhibited higher signal-to-noise ratios, contrast-to-noise ratio, and subjective scores (noise, tumour margin clarity, visualisation of bowel wall layering and MRF, overall image quality, and diagnostic confidence) than FSEstandard (p < 0.001). Reduced artefacts were observed in FSEDL for patients without spasmolytics (p < 0.05). FSEDL provided higher T-staging accuracy by junior readers than FSEstandard (reader 1, 58.33% vs 70.00%, p = 0.016; reader 3, 60.00% vs 76.67%, p = 0.021), with similar N-staging, EMVI, and MRF performance. No significant difference was observed for senior readers. FSEDL exhibited shorter diagnostic time in all readers' T-staging and overall evaluation, and junior readers' EMVI and MRF (p < 0.05). CONCLUSION: FSEDL provided improved image quality, reading time, and junior radiologists' T-staging accuracy than FSEstandard, while reducing the acquisition time by 65%. CLINICAL RELEVANCE STATEMENT: DLR is clinically applicable for rectal MRI, providing improved image quality with shorter scanning time, which may ease the examination burden. It is beneficial for diagnostic optimisation in improving junior radiologists' T-staging accuracy and reading time. KEY POINTS: The rising incidence of rectal cancer has demanded enhanced efficiency and quality in imaging examinations. FSEDL demonstrated superior image quality and had a 65% reduced acquisition time. FSEDL can improve the diagnostic accuracy of T-staging and reduce the reading time for assessing rectal cancer.

A position-enhanced sequential feature encoding model for lung infections and lymphoma classification on CT images.

PURPOSE: Differentiating pulmonary lymphoma from lung infections using CT images is challenging. Existing deep neural network-based lung CT classification models rely on 2D slices, lacking comprehensive information and requiring manual selection. 3D models that involve chunking compromise image information and struggle with parameter reduction, limiting performance. These limitations must be addressed to improve accuracy and practicality. METHODS: We propose a transformer sequential feature encoding structure to integrate multi-level information from complete CT images, inspired by the clinical practice of using a sequence of cross-sectional slices for diagnosis. We incorporate position encoding and cross-level long-range information fusion modules into the feature extraction CNN network for cross-sectional slices, ensuring high-precision feature extraction. RESULTS: We conducted comprehensive experiments on a dataset of 124 patients, with respective sizes of 64, 20 and 40 for training, validation and testing. The results of ablation experiments and comparative experiments demonstrated the effectiveness of our approach. Our method outperforms existing state-of-the-art methods in the 3D CT image classification problem of distinguishing between lung infections and pulmonary lymphoma, achieving an accuracy of 0.875, AUC of 0.953 and F1 score of 0.889. CONCLUSION: The experiments verified that our proposed position-enhanced transformer-based sequential feature encoding model is capable of effectively performing high-precision feature extraction and contextual feature fusion in the lungs. It enhances the ability of a standalone CNN network or transformer to extract features, thereby improving the classification performance. The source code is accessible at https://github.com/imchuyu/PTSFE .

Association of Definitive Radiotherapy for Esophageal Cancer and the Incidence of Secondary Head and Neck Cancers: A SEER Population-Based Study.

Background: Impact of radiotherapy (RT) for esophageal cancer (EC) patients on the development of secondary head and neck cancer (SHNC) remains equivocal. The objective of this study was to investigate the link between definitive RT used for EC treatment and subsequent SHNC. Methods: This study was conducted using the Surveillance, Epidemiology, and End Results (SEER) database to collect the data of primary EC patients. Fine-Gray competing risk regression and standardized incidence ratio (SIR) and propensity score matching (PSM) method were used to match SHNC patients with only primary head and neck cancer (HNC) patients. Overall survival (OS) rates were applied by Kaplan-Meier analysis. Results: In total, 14,158 EC patients from the SEER database were included, of which 9,239 patients (65.3%) received RT and 4,919 patients (34.7%) received no radiation therapy (NRT). After a 12-month latency period, 110 patients (1.2%) in the RT group and 36 patients (0.7%) in the NRT group experienced the development of SHNC. In individuals with primary EC, there was an increased incidence of SHNC compared to the general US population (SIR = 5.95, 95% confidence interval (CI): 5.15 - 6.84). Specifically, the SIR for SHNC was 8.04 (95% CI: 6.78 - 9.47) in the RT group and 3.51 (95% CI: 2.64 - 4.58) in the NRT group. Patients who developed SHNC after RT exhibited significantly lower OS compared to those after NRT. Following PSM, the OS of patients who developed SHNC after RT remained significantly lower than that of matched patients with only primary HNC. Conclusion: An association was discovered between RT for EC and increased long-term risk of SHNC. This work enables radiation oncologists to implement mitigation strategies to reduce the long-term risk of SHNC in patients who have received RT following primary EC.

Efficacy comparison of fruquintinib, regorafenib monotherapy or plus programmed death-1 inhibitors for microsatellite stable metastatic colorectal cancer.

BACKGROUND: Regorafenib (R) and fruquintinib (F) are the standard third-line regimens for colorectal cancer (CRC) according to the National Comprehensive Cancer Network guidelines, but both have limited efficacy. Several phase 2 trials have indicated that R or F combined with immune checkpoint inhibitors can reverse immunosuppression and achieve promising efficacy for microsatellite stable or proficient mismatch repair (MSS/pMMR) CRC. Due to the lack of studies comparing the efficacy between F, R, F plus programmed death-1 (PD-1) inhibitor, and R plus PD-1 inhibitors (RP), it is still unclear whether the combination therapy is more effective than monotherapy. AIM: To provide critical evidence for selecting the appropriate drugs for MSS/pMMR metastatic CRC (mCRC) patients in clinical practice. METHODS: A total of 2639 CRC patients were enrolled from January 2018 to September 2022 in our hospital, and 313 MSS/pMMR mCRC patients were finally included. RESULTS: A total of 313 eligible patients were divided into F (n = 70), R (n = 67), F plus PD-1 inhibitor (FP) (n = 95) and RP (n = 81) groups. The key clinical characteristics were well balanced among the groups. The median progression-free survival (PFS) of the F, R, FP, and RP groups was 3.5 months, 3.6 months, 4.9 months, and 3.0 months, respectively. The median overall survival (OS) was 14.6 months, 15.7 months, 16.7 months, and 14.1 months. The FP regimen had an improved disease control rate (DCR) (P = 0.044) and 6-month PFS (P = 0.014) and exhibited a better trend in PFS (P = 0.057) compared with F, and it was also significantly better in PFS than RP (P = 0.030). RP did not confer a significant survival benefit; instead, the R group had a trend toward greater benefit with OS (P = 0.080) compared with RP. No significant differences were observed between the R and F groups in PFS or OS (P > 0.05). CONCLUSION: FP is superior to F in achieving 6-month PFS and DCR, while RP is not better than R. FP has an improved PFS and 6-month PFS compared with RP, but F and R had similar clinical efficacy. Therefore, FP may be a highly promising strategy in the treatment of MSS/pMMR mCRC.

Multi-scale signaling and tumor evolution in high-grade gliomas.

Although genomic anomalies in glioblastoma (GBM) have been well studied for over a decade, its 5-year survival rate remains lower than 5%. We seek to expand the molecular landscape of high-grade glioma, composed of IDH-wildtype GBM and IDH-mutant grade 4 astrocytoma, by integrating proteomic, metabolomic, lipidomic, and post-translational modifications (PTMs) with genomic and transcriptomic measurements to uncover multi-scale regulatory interactions governing tumor development and evolution. Applying 14 proteogenomic and metabolomic platforms to 228 tumors (212 GBM and 16 grade 4 IDH-mutant astrocytoma), including 28 at recurrence, plus 18 normal brain samples and 14 brain metastases as comparators, reveals heterogeneous upstream alterations converging on common downstream events at the proteomic and metabolomic levels and changes in protein-protein interactions and glycosylation site occupancy at recurrence. Recurrent genetic alterations and phosphorylation events on PTPN11 map to important regulatory domains in three dimensions, suggesting a central role for PTPN11 signaling across high-grade gliomas.

Ferroelectric and Relaxor-Ferroelectric Phases Coexisting Boosts Energy Storage Performance in (Bi0.5Na0.5)TiO3-Based Ceramics.

With the intensification of the energy crisis, it is urgent to vigorously develop new environment-friendly energy storage materials. In this work, coexisting ferroelectric and relaxor-ferroelectric phases at a nanoscale were constructed in Sr(Zn1/3Nb2/3)O3 (SZN)-modified (Bi0.5Na0.5)0.94Ba0.06TiO3 (BNBT) ceramics, simultaneously contributing to large polarization and breakdown electric field and giving rise to a superior energy storage performance. Herein, a high recoverable energy density (Wrec) of 5.0 J/cm3 with a conversion efficiency of 82% at 370 kV/cm, a practical discharged energy density (Wd) of 1.74 J/cm3 at 230 kV/cm, a large power density (PD) of 157.84 MW/cm3, and an ultrafast discharge speed (t0.9) of 40 ns were achieved in the 0.85BNBT-0.15SZN ceramics characterized by the coexistence of a rhombohedral-tetragonal phase (ferroelectric state) and a pseudo-cubic phase (relaxor-ferroelectric state). Furthermore, the 0.85BNBT-0.15SZN ceramics also exhibited excellent temperature stability (25-120 °C) and cycling stability (104 cycles) of their energy storage properties. These results demonstrate the great application potential of 0.85BNBT-0.15SZN ceramics in capacitive pulse energy storage devices.

Membrane protein MHZ3 regulates the on-off switch of ethylene signaling in rice.

Ethylene regulates plant growth, development, and stress adaptation. However, the early signaling events following ethylene perception, particularly in the regulation of ethylene receptor/CTRs (CONSTITUTIVE TRIPLE RESPONSE) complex, remains less understood. Here, utilizing the rapid phospho-shift of rice OsCTR2 in response to ethylene as a sensitive readout for signal activation, we revealed that MHZ3, previously identified as a stabilizer of ETHYLENE INSENSITIVE 2 (OsEIN2), is crucial for maintaining OsCTR2 phosphorylation. Genetically, both functional MHZ3 and ethylene receptors prove essential for OsCTR2 phosphorylation. MHZ3 physically interacts with both subfamily I and II ethylene receptors, e.g., OsERS2 and OsETR2 respectively, stabilizing their association with OsCTR2 and thereby maintaining OsCTR2 activity. Ethylene treatment disrupts the interactions within the protein complex MHZ3/receptors/OsCTR2, reducing OsCTR2 phosphorylation and initiating downstream signaling. Our study unveils the dual role of MHZ3 in fine-tuning ethylene signaling activation, providing insights into the initial stages of the ethylene signaling cascade.

Coverage-dependent activation of CO over Ni/Cu(100) single atom alloys (SAAs).

Single atom alloys (SAAs) often bring new chemistry in heterogeneous catalysis and well-defined structure for the study of structure-activity relationship (SAR). However, the existing pressure gap causes the reported SARs quite divergent. Herein, we have studied CO activation over Ni/Cu(100) SAAs in ultrahigh vacuum (UHV) and millibar range. While the Ni SAAs formed on Cu(100) significantly enhance the CO adsorption strength under UHV conditions, the CO treatment at elevated pressure leads to notable surface carbon and oxygen deposition through surface reaction. Density functional theory calculations revealed that either dissociation or disproportionation is thermodynamically forbidden for the coverage of CO less than 5/16 ML. However, these two reaction pathways can be opened at higher CO coverages due to the elevated energy state involving repulsion between adsorbed CO. This work uncovers the initial activation process of CO and demonstrates one typical cause for the pressure gap in surface science study as well.

Regulating Catalytic Oxidation Enantiomers Behavior by Imparting Chiral Microenvironment in Zr-Based Metal-Organic Frameworks.

Chiral inversions of enantiomers have significantly different biological activities, so it is important to develop simple and effective methods to efficiently identify optically pure compounds. Inspired by enzyme catalysis, the construction of chiral microenvironments resembling enzyme pockets in the pore space structure of metal-organic frameworks (MOFs) to achieve asymmetric enantioselective recognition and catalysis has become a new research hotspot. Here, a super-stable porphyrin-containing material PCN-224 is constructed by solvothermal method and a chiral microenvironment around the existing catalytic site of the material is created by post-synthesis modifications of the histidine (His) enantiomers. Experimental and theoretical calculations results show that the modulation of chiral ligands around Zr oxide clusters produces different spatial site resistances, which can greatly affect the adsorption and catalytic level of the enantiomeric molecules of tryptophan guests, resulting in a good enantioselective property of the material. It provides new ideas and possibilities for future chiral recognition and asymmetric catalysis.