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Although aromatic rings are common elements in pharmaceutically active compounds, the presence of these motifs brings several liabilities with respect to the developability of a drug1. Nonoptimal potency, metabolic stability, solubility and lipophilicity in pharmaceutical compounds can be improved by replacing aromatic rings with non-aromatic isosteric motifs2. Moreover, whereas aromatic rings are planar and lack three-dimensionality, the binding pockets of most pharmaceutical targets are chiral. Thus, the stereochemical configuration of the isosteric replacements may offer an added opportunity to improve the affinity of derived ligands for target receptors. A notable impediment to this approach is the lack of simple and scalable catalytic enantioselective syntheses of candidate isosteres from readily available precursors. Here we present a previously unknown palladium-catalysed reaction that converts hydrocarbon-derived precursors to chiral boron-containing nortricyclanes and we show that the shape of these nortricyclanes makes them plausible isosteres for meta disubstituted aromatic rings. With chiral catalysts, the Pd-catalysed reaction can be accomplished in an enantioselective fashion and subsequent transformation of the boron group provides access to a broad array of structures. We also show that the incorporation of nortricyclanes into pharmaceutical motifs can result in improved biophysical properties along with stereochemistry-dependent activity. We anticipate that these features, coupled with the simple, inexpensive synthesis of the functionalized nortricyclane scaffold, will render this platform a useful foundation for the assembly of new biologically active agents.A palladium-catalysed reaction converts hydrocarbon-derived precursors to chiral boron-containing nortricyclanes, and the shape of these nortricyclanes makes them plausible isosteres for meta disubstituted aromatic rings. [ABSTRACT FROM AUTHOR]

The explosive growth of dialogue data has aroused significant interest among scholars in abstractive dialogue summarization. In this paper, we propose a novel sequence-to-sequence framework called DS-SS (Dialogue Summarization with Factual-Statement Fusion and Dialogue Segmentation) for summarizing dialogues. The novelty of the DS-SS framework mainly lies in two aspects: 1) Factual statements are extracted from the source dialogue and combined with the source dialogue to perform the further dialogue encoding; and 2) A dialogue segmenter is trained and used to separate a dialogue to be encoded into several topic-coherent segments. Thanks to these two aspects, the proposed framework may better encode dialogues, thereby generating summaries exhibiting higher factual consistency and informativeness. Experimental results on two large-scale datasets SAMSum and DialogSum demonstrate the superiority of our framework over strong baselines, as evidenced by both automatic evaluation metrics and human evaluation. [ABSTRACT FROM AUTHOR]

Dipeptidyl Peptidase IV (DPP-IV) inhibitory peptides are attracting increasing attention, owing to their potential role in glycemic regulation by preventing the inactivation of incretins. However, few reviews have summarized the current understanding of DPP-IV inhibitory peptides and their knowledge gaps. This paper reviews the production, identification and structure-activity relationships (SAR) of DPP-IV inhibitory peptides. Importantly, their bioavailability and hypoglycemic effects are critically discussed. Unlike the traditional method to identifying peptides after separation step by step, the bioinformatics approach identifies peptides via virtual screening that is more convenient and efficient. In addition, the bioinformatics approach was also used to investigate the SAR of peptides. Peptides with proline (Pro) or alanine (Ala) residue at the second position of N-terminal are exhibit strong DPP-IV inhibitory activity. Besides, the bioavailability of DPP-IV inhibitory peptides is related to their gastrointestinal stability and cellular permeability, and in vivo studies showed that the glucose homeostasis has been improved by these peptides. Especially, the intestinal transport of DPP-IV inhibitory peptides and cell biological assays used to evaluate their potential role in glycemic regulation are innovatively summarized. For further successful development of DPP-IV inhibitory peptides in glycemic regulation, future study should elucidate their SAR and in vivo hypoglycemic effects. [ABSTRACT FROM AUTHOR]

Background: Functional connectivity (FC) biomarkers play a crucial role in the early diagnosis and mechanistic study of Alzheimer's disease (AD). However, the identification of effective FC biomarkers remains challenging. In this study, we introduce a novel approach, the spatiotemporal graph convolutional network (ST-GCN) combined with the gradient-based class activation mapping (Grad-CAM) model (STGC-GCAM), to effectively identify FC biomarkers for AD. Methods: This multi-center cross-racial retrospective study involved 2,272 participants, including 1,105 cognitively normal (CN) subjects, 790 mild cognitive impairment (MCI) individuals, and 377 AD patients. All participants underwent functional magnetic resonance imaging (fMRI) and T1-weighted MRI scans. In this study, firstly, we optimized the STGC-GCAM model to enhance classification accuracy. Secondly, we identified novel AD-associated biomarkers using the optimized model. Thirdly, we validated the imaging biomarkers using Kaplan–Meier analysis. Lastly, we performed correlation analysis and causal mediation analysis to confirm the physiological significance of the identified biomarkers. Results: The STGC-GCAM model demonstrated great classification performance (The average area under the curve (AUC) values for different categories were: CN vs MCI = 0.98, CN vs AD = 0.95, MCI vs AD = 0.96, stable MCI vs progressive MCI = 0.79). Notably, the model identified specific brain regions, including the sensorimotor network (SMN), visual network (VN), and default mode network (DMN), as key differentiators between patients and CN individuals. These brain regions exhibited significant associations with the severity of cognitive impairment (p < 0.05). Moreover, the topological features of important brain regions demonstrated excellent predictive capability for the conversion from MCI to AD (Hazard ratio = 3.885, p < 0.001). Additionally, our findings revealed that the topological features of these brain regions mediated the impact of amyloid beta (Aβ) deposition (bootstrapped average causal mediation effect: β = -0.01 [-0.025, 0.00], p < 0.001) and brain glucose metabolism (bootstrapped average causal mediation effect: β = -0.02 [-0.04, -0.001], p < 0.001) on cognitive status. Conclusions: This study presents the STGC-GCAM framework, which identifies FC biomarkers using a large multi-site fMRI dataset. [ABSTRACT FROM AUTHOR]

Flaxseed has been recognized as a superfood worldwide due to its abundance of diverse functional phytochemicals and nutrients. Various studies have shown that flaxseed consumption is beneficial to human health, though methods of processing flaxseed may significantly affect the absorption and metabolism of its bioactive components. Hence, flaxseed was subjected to various processing methods including microwaving treatment, microwave-coupled dry milling, microwave-coupled wet milling, and high-pressure homogenization. In vitro digestion experiments were conducted to assess the impact of these processing techniques on the potential gastrointestinal fate of flaxseed oil. Even though more lipids were released by the flaxseed at the beginning of digestion after it was microwaved and dry-milled, the full digestion of flaxseed oil was still restricted in the intestine. In contrast, oil droplets were more evenly distributed in wet-milled flaxseed milk, and there was a greater release of fatty acids during simulated digestion (7.33 ± 0.21 μmol/mL). Interestingly, wet-milled flaxseed milk showed higher oxidative stability compared with flaxseed powder during digestion despite the larger specific surface area of its oil droplets. This study might provide insight into the choice of flaxseed processing technology for better nutrient delivery efficiency. [ABSTRACT FROM AUTHOR]

Objective: To explore the association between the apolipoprotein E (APOE) genotype and objectively assessed cognitive function. Methods: In this cross-sectional study, 537 participants underwent a neuropsychological assessment for cognitive function and blood testing for APOE genotype. Based on cognitive test results, participants were stratified into two cohorts: Cognitively Unimpaired participants (CU) and Cognitively Impaired participants (CI). The CI group was further divided into Mild Cognitive Impairment (MCI) and Alzheimer's Disease (AD). Furthermore, we conducted age stratification, categorizing participants into three age groups: age 1: <65 years, age 2: 65–75 years, and age 3: >75 years. We assessed the disparities in cognitive function associated with ε4 carrier status across different age brackets. Plasma amyloid-β levels were measured in a cohort of 294 participants to investigate potential interactions involving ε4 carrier status, diagnosis, sex, or plasma markers. Results: The APOE genotypic distribution among the 537 participants was characterized as follows: ε2/ε2 (5 participants), ε2/ε3 (67), ε2/ε4 (13), ε3/ε3 (330), ε3/ε4 (113), and ε4/ε4 (9). Allele frequencies were: ε3 at 78.21%, ε4 at 13.41%, and ε2 at 8.38%. Notably, the ε4 carrier frequency was markedly elevated in the AD group at 81.8% when compared to MCI at 32.8% and CU at 21.3% (p < 0.05). Within the Cognitively Unimpaired (CU) cohort, the sole discernible contrast between ε4+ and ε4− emerged in STT-B (p < 0.05). Within the CI group, ε4 carriers showed statistically poorer scores as compared to non-ε4 carriers in several cognitive tests (p < 0.05). Age stratification result revealed that, among ε4 carriers, cognitive function scores within the age 3 group were significantly inferior to those of age 1 and age 2 groups (p < 0.05). Plasma amyloid-β detection was applied to the 294 participants. We tested plasma amyloid-β (Aβ42) and plasma amyloid-β (Aβ40) levels and calculated the Aβ42/Aβ40 ratio. We found that among female ε4 carriers, both Aβ42 and the Aβ42/Aβ40 ratio were notably lower than their male counterparts (p < 0.05). Conclusions: The ε3/ε3 was the most prevalent among participants, succeeded by ε3/ε4 and ε2/ε3. The least prevalent were ε2/ε4, ε4/ε4, and ε2/ε2 genotypes. The ε3 was predominant, followed by the ε4 and ε2. Individuals with the ε4 allele exhibited significant cognitive impairment, with an especially high prevalence in AD group at 81.8%. The study unveils a pronounced correlation between the ε4 allele and cognitive deficits, implying its potential role in the advancement and severity of cognitive disorders, notably Alzheimer's disease. Cognitive function declines with age in individuals carrying the ε4, and women are more affected by ε4. [ABSTRACT FROM AUTHOR]

Both plasma biomarkers and brain network topology have shown great potential in the early diagnosis of Alzheimer's disease (AD). However, the specific associations between plasma AD biomarkers, structural network topology, and cognition across the AD continuum have yet to be fully elucidated. This retrospective study evaluated participants from the Sino Longitudinal Study of Cognitive Decline cohort between September 2009 and October 2022 with available blood samples or 3.0‐T MRI brain scans. Plasma biomarker levels were measured using the Single Molecule Array platform, including β‐amyloid (Aβ), phosphorylated tau181 (p‐tau181), glial fibrillary acidic protein (GFAP), and neurofilament light chain (NfL). The topological structure of brain white matter was assessed using network efficiency. Trend analyses were carried out to evaluate the alterations of the plasma markers and network efficiency with AD progression. Correlation and mediation analyses were conducted to further explore the relationships among plasma markers, network efficiency, and cognitive performance across the AD continuum. Among the plasma markers, GFAP emerged as the most sensitive marker (linear trend: t = 11.164, p = 3.59 × 10−24; quadratic trend: t = 7.708, p = 2.25 × 10−13; adjusted R2 = 0.475), followed by NfL (linear trend: t = 6.542, p = 2.9 × 10−10; quadratic trend: t = 3.896, p = 1.22 × 10−4; adjusted R2 = 0.330), p‐tau181 (linear trend: t = 8.452, p = 1.61 × 10−15; quadratic trend: t = 6.316, p = 1.05 × 10−9; adjusted R2 = 0.346) and Aβ42/Aβ40 (linear trend: t = −3.257, p = 1.27 × 10−3; quadratic trend: t = −1.662, p = 9.76 × 10−2; adjusted R2 = 0.101). Local efficiency decreased in brain regions across the frontal and temporal cortex and striatum. The principal component of local efficiency within these regions was correlated with GFAP (Pearson's R = −0.61, p = 6.3 × 10−7), NfL (R = −0.57, p = 6.4 × 10−6), and p‐tau181 (R = −0.48, p = 2.0 × 10−4). Moreover, network efficiency mediated the relationship between general cognition and GFAP (ab = −0.224, 95% confidence interval [CI] = [−0.417 to −0.029], p =.0196 for MMSE; ab = −0.198, 95% CI = [−0.42 to −0.003], p =.0438 for MOCA) or NfL (ab = −0.224, 95% CI = [−0.417 to −0.029], p =.0196 for MMSE; ab = −0.198, 95% CI = [−0.42 to −0.003], p =.0438 for MOCA). Our findings suggest that network efficiency mediates the association between plasma biomarkers, specifically GFAP and NfL, and cognitive performance in the context of AD progression, thus highlighting the potential utility of network‐plasma approaches for early detection, monitoring, and intervention strategies in the management of AD. [ABSTRACT FROM AUTHOR]

Actual chemical states of single-atom metal on reducible supports remain a fiercely debated topic under reactive environments. Herein, we demonstrate that the single-atom Pt on Co3O4 surface undergoes an in-situ reconstruction to form isolated Pt-Co bimetallic sites via reducing coordination number of Pt—O in the presence of hydrogen from both simulations and in-situ X-ray photoelectron spectroscopy. The modified chemical states of Pt greatly promoted H2 activation, thus delivering a significantly high turnover frequency of 7,448 h−1 (19.5 times over Pt nanoparticles on Co3O4) for hydrogenation of cinnamaldehyde. The satisfactory selectivity of 95.2% towards cinnamyl alcohol was ascribed to a tilted adsorption configuration of reactant on the catalyst surface via aldehyde group. We anticipate that the recognitions on in-situ reconstruction of single-atom catalysts (SACs) under the reducing conditions benefit the design of highly-performed hydrogenation catalysts. [ABSTRACT FROM AUTHOR]

Carbon neutrality initiative has stimulated the development of the sustainable methodologies for hydrogen generation and safe storage. Aqueous-phase reforming methanol and H2O (APRM) has attracted the particular interests for their high gravimetric density and easy availability. Thus, to efficiently release hydrogen and significantly suppress CO generation at low temperatures without any additives is the sustainable pursuit of APRM. Herein, we demonstrate that the dual-active sites of Pt single-atoms and frustrated Lewis pairs (FLPs) on porous nanorods of CeO2 enable the efficient additive-free H2 generation with a low CO (0.027%) through APRM at 120 °C. Mechanism investigations illustrate that the Pt single-atoms and Lewis acidic sites cooperatively promote the activation of methanol. With the help of a spontaneous water dissociation on FLPs, Pt single-atoms exhibit a significantly improved reforming of *CO to promote H2 production and suppress CO generation. This finding provides a promising path towards the flexible hydrogen utilizations. Carbon neutrality initiative has stimulated the development of the sustainable methodologies for hydrogen generation and safe storage. Here the authors demonstrate that the dual-active sites of Pt single-atoms and frustrated Lewis pairs on porous nanorods of CeO2 enable the efficient additive-free H2 generation with a low CO generation through reforming of methanol and water. [ABSTRACT FROM AUTHOR]

BACKGROUND: The INFOGEST model is a standardized general in vitro digestion study, but it cannot accurately simulate the fatty acid release process of lipids in the stomach and small intestine. In this study, the internationally universal INFOGEST 2019 was used as the basic model and flaxseed oil emulsion was used as the research object. In various improvement models, the effect of fatty acid release rate on the oxidation stability of flaxseed oil was assessed by adding rabbit stomach extract and changing the order of bile salts addition. RESULTS: With the presence of rabbit gastric extract, flaxseed oil emulsion flocculation and coalescence in stomach were reduced, and the absolute value of ζ‐potential increased. Moreover, the release rate of fatty acids in the small intestine increased by 12.14%. The amount of lipid oxidation product (i.e. hexanal) in the gastric and intestinal phases increased by 0.08 ppb. In addition, the fatty acid release rate in the small intestine phase increased by 5.85% and the hexanal content increased by 0.011 ppb in the digestion model of adding bile salts before adjusting the pH in the small intestine phase compared with the model of adjusting the pH first and then adding bile salts. CONCLUSION: The results obtained from this study will contribute to finding the most suitable static digestion model for simulating digestion and oxidation of lipid during lipid gastrointestinal digestion. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this paper is described an easily synthesized chiral diazaborolidine that is inexpensive, stable, and provides excellent stereoselection across a number of reaction classes. These versatile compounds possess utility in four different classes of cycloaddition reactions, offering good yield and stereoselectivity. X‐ray structure analysis provides insight about the origin of stereocontrol. [ABSTRACT FROM AUTHOR]

In this paper is described an easily synthesized chiral diazaborolidine that is inexpensive, stable, and provides excellent stereoselection across a number of reaction classes. These versatile compounds possess utility in four different classes of cycloaddition reactions, offering good yield and stereoselectivity. X‐ray structure analysis provides insight about the origin of stereocontrol. [ABSTRACT FROM AUTHOR]

Regulation of the catalyst interface by adsorbates has been demonstrated as an efficacious methodology to enhance the catalytic selectivity. Herein, we demonstrated an in situ modifications induced by reactants to re‐construct the local interface of Pt nanoparticles anchored on the CoFe layered double hydroxides (CoFe‐LDH) supports for a highly selective synthesis of primary amines from reductive amination of aldehydes and ammonia. The strong metal‐support interaction between Pt metals and CoFe‐LDH supports results in the highly electron‐enriched surface of Pt and thereby makes the surface of Pt nanoparticles favor the enrichment of NH4+ species and adsorption of NH3. Such a tailored interface can create an interfacial stereo‐hindrance effect and effectively slug the reaction kinetics of side‐reactions, further preventing the formation of side‐products. We anticipate that such an in situ re‐construction of metal interface by reactants and afterwards the constructed local environment of active sites may provide a new approach for the optimization of metal catalysts. [ABSTRACT FROM AUTHOR]

Industrial robots play an important role in the milling of large complex parts. However, the robot is less rigid and prone to vibration-related problems; chatter, which affects machining quality and efficiency, is more complex and difficult to monitor. In this paper, a variational mode decomposition-support vector machine (VMD-SVM) model based on information entropy (IE) is built to detect chatter in robotic milling. Significantly, the vibration signals are classified into four states for the first time: stable, transition, regular chatter, and irregular chatter. To improve the accuracy of the identification model based on VMD-SVM, a novel hyper-parameter optimization strategy—the kMap method—is proposed in this paper for optimizing three-dimensional hyper-parameters in the VMD-SVM model. The hyper-parameters of VMD-SVM are jointly optimized by the kMap method, with constant step sizes. As an improved grid search (GS), kMap reduces the operation time to the same order of magnitude as the heuristic algorithm (HA) [comprising particle swarm optimization (PSO) and genetic algorithm (GA)]. The VMD-SVM model with the hyper-parameters optimized by kMap exhibits higher accuracy and better stability than the hyper-parameters optimized by PSO and GA. The results of the validation experiments show that the kMap-optimized identification model is effective in industrial robotic milling. [ABSTRACT FROM AUTHOR]

This document is an erratum for a paper titled "A stereo photogrammetry system for model position and attitude measurement in hypersonic wind tunnel testing" published in the Review of Scientific Instruments. The erratum addresses the withdrawal of author Lei Chen and designates Jin Liang as the corresponding author. The revised author list includes Mingkai Zhang, Jin Liang, Zhengzong Tang, and Yulong Zong. The erratum ensures compliance with the journal's guidelines and reflects the necessary adjustments in the authorship list. The document also includes declarations of author contributions. [Extracted from the article]

Epoxides are versatile intermediates in the production of a diverse set of chemical products. The direct epoxidation of alkenes using O2 represents an environmentally friendly and economical process to replace the use of expensive H2O2 or organic peroxides for the synthesis of epoxides. Herein, single-atom Co anchored on N-doped carbon supports with a multiscale porous structure (Co1/NC-h) has been successfully constructed by etching CoZn-ZIF metal–organic framework precursors before a carbonation process. Benefitting from the high intrinsic activity of Co–Nx active sites and the more accessibly exposed reactive sites of multiscale porous structures, the Co1/NC-h catalysts can achieve the epoxidation of cyclooctene with 95% yield of 1,2-epoxycycloheptane at 140 °C and 0.5 MPa O2. This research opens up opportunities for designing high-performance single-atom catalysts towards applications in diverse heterogeneous catalysis. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a common neurodegenerative disease with progressive gait, cognition, and overall functional decline. Surface area changes are frequently seen with aging. In neurodegenerative diseases, the changes can be evident with disease progression. The current study aimed to study the regional microstructural alterations using surface-based morphometry to correlate with gait measures of the pace and rhythm domains in PD patients. We hypothesize that specific regional surface changes can be associated with PD gait impairments. Surface analysis might provide a useful tool for assessing PD for functional status and specific motor domains, such as gait in PD, and potentially could serve as an imaging marker in conjunction with other imaging markers. Twenty-seven PD patients and 37 healthy controls were included. The clinical assessment included Mini-Mental State Exanimation, PD motor assessment, clinical gait testing, and objective/quantitative gait assessment. For patients with PD, all motor and gait testing were performed during both OFF and ON medication states. Three Tesla MRI and high-resolution 3D structural images were acquired with an MP-RAGE pulse sequence. Structural image data preprocessing was performed using the DPABISurf toolbox. Clinical characteristics between PD and control group were compared, and correlation between the surface area and behavioral data were analyzed. At the left lateral temporal cortex (LTC) and right inferior parietal cortex (IPC), PD patients have significantly larger surface areas when compared to controls (P < 0.05) using surface-based morphometry. The surface area changes of the left LTC and right IPC were associated with the worse performance of gait assessed by Berg Balance Scale and Timed Up and Go during OFF (P < 0.01). The left LTC area changes significantly correlated with the number of steps, velocity, and the stride length of the pace domain in the ON state. Our findings suggest that PD is associated with a characteristic regional pattern of larger surface area in the left LTC and right IPC. These regional changes were associated with the pace domain of the gait in the ON state. Overall, surface-based analyses might provide a useful tool for assessing PD for functional status and specific motor domains, such as gait in PD, and potentially could serve as an imaging marker. [ABSTRACT FROM AUTHOR]

Catalytic synthesis of aromatic azo compounds by oxidative coupling of anilines using molecular oxygen represents a facile, green and valuable process; however, such an economical process suffers from poor catalytic activity and selectivity. Herein, novel single crystal MnOOH nanotubes with abundant Mn3+ sites and high oxygen defects were successfully synthesized. The catalyst exhibited high selectivity for oxidative coupling of anilines, achieving complete transformation into aromatic azo compounds under mild conditions, even at room temperature. [ABSTRACT FROM AUTHOR]

In this paper, a measurement system based on stereo photogrammetry is proposed for position and attitude measurements of test models in hypersonic wind tunnel testing. Several adaptations were made to an existing stereo photogrammetry system to promote its routine use as a primary wind tunnel measurement system. First, cameras were installed in the wind tunnel test section to decrease the measurement distance and increase the base length, which helped improve the measurement accuracy. To deal with camera vibration caused by the freestream, a camera orientation method is proposed to estimate the exterior parameters of each frame relative to the tunnel coordinate system. Second, a scheme to determine the model coordinate system is proposed, which does not require placement of the targets at known locations of the model. Third, to solve the recognition problem of motion-blurred target images, a network was adopted for stereo deblurring and a stereo blur dataset simulating the wind tunnel test environment was generated for network training. To develop the novel stereo photogrammetry system, experiments were conducted in both the laboratory and a hypersonic wind tunnel at the China Aerodynamics Research and Development Center. The experimental results suggest that the proposed measurement system is practicable for position and attitude measurements of test models in hypersonic wind tunnel testing. [ABSTRACT FROM AUTHOR]

Hydrogen spillover phenomenon of metal-supported electrocatalysts can significantly impact their activity in hydrogen evolution reaction (HER). However, design of active electrocatalysts faces grand challenges due to the insufficient understandings on how to overcome this thermodynamically and kinetically adverse process. Here we theoretically profile that the interfacial charge accumulation induces by the large work function difference between metal and support (∆Φ) and sequentially strong interfacial proton adsorption construct a high energy barrier for hydrogen transfer. Theoretical simulations and control experiments rationalize that small ∆Φ induces interfacial charge dilution and relocation, thereby weakening interfacial proton adsorption and enabling efficient hydrogen spillover for HER. Experimentally, a series of Pt alloys-CoP catalysts with tailorable ∆Φ show a strong ∆Φ-dependent HER activity, in which PtIr/CoP with the smallest ∆Φ = 0.02 eV delivers the best HER performance. These findings have conclusively identified ∆Φ as the criterion in guiding the design of hydrogen spillover-based binary HER electrocatalysts. Despite the significance of hydrogen spillover on metal-supported electrocatalysts for hydrogen evolution, fundamental understandings on such a process are insufficient. Here the authors show that small work function difference between metal and support facilitates hydrogen spillover and enhances activity. [ABSTRACT FROM AUTHOR]

Precisely controlling the spatial intimacy of multiple active sites at sub-nanoscale in heterogeneous catalysts can improve their selectivity and activity. Herein, we realize a highly selective nitrile-to-secondary imine transformation through a cascaded hydrogenation and condensation process by Pt1/CoBOx comprising the binary active sites of the single-dispersed Pt and interfacial Lewis acidic B. Atomic Pt sites with large inter-distances (>nanometers) only activate hydrogen for nitrile hydrogenation, but inhibit condensation. Both adjacent B...B on CoBOx and neighbouring Pt...B pairs with close intimacy of ~0.45 nm can satisfy the spatial prerequisites for condensation. Mechanism investigations demonstrate the energetically favorable pathway occurred on adjacent Lewis acidic B sites through the nitrile adsorption (acid-base interaction), hydrogenation via hydrogen spillover from Pt to B sites and sequential condensation. Strong intermolecular tension and steric hindrance of secondary imines on active sites lead to their effective desorption and thereby a high chemoselectivity of secondary imines. Precisely controlling the spatial intimacy of multiple active sites in heterogeneous catalysts can significantly affect the selectivity and activity. Here the authors show a binary active site of single atom Pt and Lewis acidic B with spatial intimacy enables a highly selective nitrile-to-secondary imine transformation. [ABSTRACT FROM AUTHOR]

Here, we report a facile synthetic methodology to prepare uniform single crystalline CeO2 nanotubes through a hydrothermal transformation of CeO2 nanorods in aqueous Ce(NO3)3 solution. A chemically driven etching-dissolution-deposition mechanism is proposed, involving the surface Ce3+ hydrolysis and dissolution at tips of nanorods and subsequent redeposition and crystallization on the outer sides of nanorods. Compared to CeO2 nanorods, CeO2 nanotubes exhibited the richer structural defects, higher reducibility and larger surface area, leading to a higher haloperoxidase-like activity. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is a frequently occurring tumor. Although a number of long noncoding RNAs have been researched in CRC, the expression, function and mechanism of AGAP2‐AS1 remains poorly investigated. Methods: Gene expression was analyzed by a quantitative reverse transcriptase‐polymerase chain rreaction and western blot analyses. Cell counting kit‐8, colony formation and Transwell assays were utilized to explore the functional role of AGAP2‐AS1 in CRC. Luciferase reporter, RNA pull down and RNA immunoprecipitation assays were implemented to verify relationships between RNA molecules. Results: In the present study, AGAP2‐AS1 was unveiled as highly expressed in CRC cell lines compared to normal cells. AGAP2‐AS1 knockdown suppressed cell proliferation, migration, invasion and the epithelial‐to‐mesenchymal transition process. Interestingly, AGAP2‐AS1 sponges miR‐4,668‐3p to release SRSF1 in CRC. Furthermore, in the rescue functional assay, miR‐4,668‐3p down‐regulation exacerbated the malignant behaviors of AGAP2‐AS1‐depleted CRC cells, whereas such effects were further offset by SRSF1 knockdown. Conclusions: AGAP2‐AS1 facilitates cell proliferation, motility and EMT in CRC via targeting the miR‐4,668‐3p/SRSF1 axis. AGAP2‐AS1 or SRSF1 may have potential as underlying therapeutic targets for CRC patients. [ABSTRACT FROM AUTHOR]

Objective: Early diagnosis remains the primary goal for leprosy management programs. This study aims to determine whether active surveillance of patients with leprosy and their contact individuals increased identification of latent leprosy cases in the low-endemic areas. Methods: This cross-sectional survey was carried out between October 2014 and August 2016 in 21 counties throughout Shandong Province. The survey was conducted among patients with leprosy released from treatment (RFT) and their contacts from both household and neighbors. Results: A total of 2,210 RFT patients and 9,742 contacts comprising 7877 household contacts (HHCs), including 5,844 genetic related family members (GRFMs) and 2033 non-genetic related family members and 1,865 contacts living in neighboring houses (neighbor contacts, NCs), were recruited. Among identified individuals, one relapsed and 13 were newly diagnosed, giving a detection rate of 0.12%, corresponding to 120 times the passive case detection rate. Detection rates were similar for HHCs and NCs (0.114% vs. 0.214%, P = 0.287). Analysis of the family history of leprosy patients revealed clustering of newly diagnosed cases and association with residential coordinates of previously-diagnosed multibacillary leprosy cases. Conclusion: Active case-finding programs are feasible and contributes to early case detection by tracking HHCs and NCs in low-endemic areas. Author summary: Leprosy has been eliminated as a public health problem in 1994 in Shandong Province. However, the district continues to report a relatively high number of cases of leprosy infection involving deformity. Several studies have shown that individuals in contact with people infected with leprosy are at high risk of developing the disease. Subclinical infections among such individuals are important in the chain of M. leprae transmission. Some hyperendemic areas show growing interest in active case finding (ACF). Recent data from the World Health Organization (WHO) show that high rates of relapsed patients, grade 2 disability (G2D) since 2011, and the extensive family history of leprosy among people in Shandong Province P.R. China, indicate a need to reconsider the current approach to leprosy prevention. Active case finding was conducted in 21 counties of Shandong Province among patients with leprosy released from treatment (RFT) and their contacts. We achieved a detection rate of 0.12%, which was much higher than the rate for passive case finding. Our ACF program confirmed the need to implement this strategy among families and neighbors of RFT patients in historically high-endemic areas of leprosy. The program could reduce the risk of G2D by facilitating early detection and treatment, thereby reducing the disease burden. [ABSTRACT FROM AUTHOR]

This study aims to propose a multi-point integrated real-time control method based on discrete dynamic water level variations, which can be realized only based on the programmable logic controller (PLC) system without using a complex mathematical model. A discretized water level control model was developed to conduct the real-time control based on data-automation. It combines the upstream pumping stations and the downstream influent pumping systems of wastewater treatment plant (WWTP). The discretized water level control method can regulate dynamic wastewater pumping flow of pumps following the dynamic water level variation in the sewer system. This control method has been successfully applied in practical integrated operations of sewer-WWTP following the sensitive flow disturbances of the sewer system. The operational results showed that the control method could provide a more stabilized regulate pumping flow for treatment process; it can also reduce the occurrence risk of combined sewer overflow (CSO) during heavy rainfall events by increasing transport capacity of pumping station and influent flow in WWTP, which takes full advantage of storage space in the sewer system. [ABSTRACT FROM AUTHOR]

The transient signal caused by localized fault in rotating machinery always contains complex modulation information with heavy background noise distributed, which brings much difficulties for fault feature identification in the application of rotating machinery fault diagnosis. Focusing on the sensitive feature extraction from these complex signals, this paper proposes a novel variational mode manifold reinforcement learning (VM2RL) to adaptively construct time-frequency synthesis analysis for enhancement of transient features. First, a method of adaptive variational mode decomposition (VMD) is employed to divide the raw spectrum of the given signal into several sub-bands with different frequency modulation information. Second, an improved time-frequency manifold (ITFM) learning is introduced to gain the topological manifold structure from those sub-distributions in time-frequency domain. Then, a sound-enhanced signature of transient features on the whole time-frequency plane can be synthesized by combining those sub-TFMs from each modulated segment back to the corresponding frequency band. Finally, the time-frequency envelope spectrum for fault diagnosis is further obtained through statistically evaluating their amplitude distribution. Among them, short-frequency Fourier transform (SFFT) is introduced to transform local frequency bands into a series of TFDs which improves the computational efficiency of TFM learning. In this manner, the desired transient distribution on full time-frequency plane can be automatically reconstructed by VM2RL with manifold reinforced in a data-driven way. A simulation study and two experimental signals are both analyzed here, and fast spectral kurtosis and conventional VMD methods are also used to verify its effectiveness. Meanwhile, a quantitative analysis has been provided to further illustrate its superiority in the application of complex signal fault of rotating machinery. [ABSTRACT FROM AUTHOR]

A novel strategy through a temperature-responsive dissolution and recrystallization process has successfully achieved 100% atomic utilization and easy recyclability of heterogeneous metal organic framework dimethylammonium zinc formate (DMZnF) catalysts for highly efficient dehydrogenation of DMF–H2O for hydrogen generation. DMZnF dissolves as a homogeneous catalyst at high reaction temperatures and then is recrystallized and recycled as a heterogeneous catalyst at low temperatures. [ABSTRACT FROM AUTHOR]

Several studies have certified that autoantibodies play an important role in the manifestation of neuromuscular diseases. Scientists have discovered specific neuronal tumor antibodies in patients with typical paraneoplastic neurological disorders. But in some clinical cases, it is not useful to cure this disease with common treatments unless the autoantibodies are addressed. In addition, recent studies have shown a close relationship between certain antibodies and neuronal surface proteins in some special cases. These antibodies, which act on the surface of neurons, mainly include voltage-gated calcium channel (VGKC) antibodies. VGKC antibodies are further divided into several types including anti-leucine-rich glioma inactivated 1 (LGI1), anti-contactin-associated protein-like 2 (Caspr2), anti-N-methyl-D-aspartate receptor (NMDAR), anti-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR), anti-γ-aminobutyric acid receptor (GABAR), and glycine receptor. For the purpose of this review, cases of clinical studies of autoantibody-associated encephalitis were collected, the key points regarding the pathogenesis were summarized, the clinical manifestation was discussed, and all this information was organized as this review in order to introduce the relationship between autoantibodies and autoimmune encephalitis. Furthermore, it is hoped that it can effectively direct the development of diagnostic and therapeutic approach in the future. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER) severely restricts the efficiency of electrolyzers due to its sluggish kinetics. In particular, only a few OER electrocatalysts, such as expensive and scarce iridium (Ir)‐based materials, have been developed to function in acidic media. Therefore, the exploration of efficient and stable electrocatalysts with decreased precious metal content for the OER in acid is desired. Herein, chromium (Cr)‐incorporated IrOx solid solution nanowires not only exhibit high catalytic activity with a low overpotential of 250 mV at 10 mA cm−2, but also display robust catalytic performance without a decay in activity throughout 25 h of testing at 10 mA cm−2 in 0.5 M H2SO4. This improved catalytic performance for the Cr‐incorporated IrOx electrocatalysts is ascribed to an abundance of exposed active sites, tuned electronic states, optimized binding energy for intermediates on the catalyst surface and the consequent facile reaction kinetics. [ABSTRACT FROM AUTHOR]

A new type of modular metamaterials with reprogrammable mechanical properties is proposed based on the multistability in decoupled units. This metamaterial consists of periodically arranged foldable obelisk-like (FO) units, and each unit has three interchangeable states: two different soft states and a stiff state. Therefore, such metamaterial can possess various mechanical properties with different state combinations of units. Both theoretical and experimental investigations are conducted to understand the multistability in one unit and the reprogrammed mechanical properties in a two-dimensional tessellation. Additionally, we investigate the inverse question that whether the identical force response can be generated with different geometrical design of the metamaterial and propose a way to build 3D metamaterials with intended architectures. This work establishes general principles for designing mechanical metamaterials with independently transformable modules, and opens new avenues for various potential applications such as: self-locking materials, impact mitigation and stiffness transformation materials. [ABSTRACT FROM AUTHOR]

Electrocatalytic hydrogen evolution reaction (HER) through transition‐metal‐based (TMB) catalysts represents a totally sustainable and cost‐effective technology for practical hydrogen (H2) production with high purity. Unfortunately, most of the catalysts have the unsuitable hydrogen adsorption behavior and thereby insufficient H2 generation efficiency. The general strategy to address the problem is to introduce various cation or/and anion dopants for designing multivariate TMB catalysts, which comes down to the optimized electronic structures and thus hydrogen adsorption of surface active sites. In this minireview, we summarize the recent significant advances in multivariate TMB catalysts for HER, especially highlighting the contributions of various dopants as the modulator for the host materials. Finally, the remaining challenges and future perspectives on multivariate TMB catalysts for HER are also discussed. [ABSTRACT FROM AUTHOR]

Leaching of pyrite-type catalysts induced by surface oxidation and galvanic corrosion is a sign of poor electrocatalytic durability and limits their potential for the electrocatalytic hydrogen evolution reaction (HER). Weakened O2 adsorption on pyrites can suppress both oxidation and corrosion, preventing the loss of electroactive components and maintaining their activity. Herein, we report our strategy theoretically and experimentally to establish an engineered CoS2 surface by Ce-doping which exhibits improved electrochemical stability against galvanic corrosion and enhanced chemical stability against ambient surface oxidation for an efficient and robust HER in alkali over 250 h. The Ce-doped CoS2 electrode delivered an activity–durability factor of ∼31 times higher than that of the CoS2 electrode, indicating the highly stabilized HER activity. Characterization tests on the spent Ce-doped CoS2 showed negligible corrosion current and leached Co ions in the electrolyte, further demonstrating that the Ce-doping protected CoS2 from oxidation- and corrosion-induced leaching. [ABSTRACT FROM AUTHOR]

Controlled multi-pulse loading has seldom been applied in classical split Hopkinson pressure bar (SHPB) research. Therefore, a new technique is proposed to realize a controlled multi-pulse loading SHPB experiment, and a miniature multi-pulse series reluctance coil launcher is developed. The micro-multi-pulse series reluctance coil emitter consists of two single-stage reluctance coils and two impact bars. Two loading pulses with the same amplitude are produced by driving the two impact bars to successively impact the incident bar. The distance between the impact bars controls the delay of the second pulse relative to the first one. The delay can be controlled by adjusting the distance between the impact bars and the launch speed. This precise multi-pulse loading technique is easy to implement and can be used to measure and study the dynamic response of various materials in loading SHPB experiments. [ABSTRACT FROM AUTHOR]

In this study, the effects of different process parameters on the yield of aromatics (YA) and the yield of C5+ (YC5+) were studied through catalytic reforming experiments of coal-derived naphtha (CDN). First, the optimum process parameters of CDN catalytic reforming were weighted average inlet temperature (WAIT) for (500-520 °C), pressure (P) for (1.2-1.6 MPa), liquid hourly space velocity (LHSV) for (2.0-3.0 h−1), hydrogen-oil volume ratio (VH/VO) for (600:1). The optimum conditions were WAIT 516 °C, P 1.4 MPa, LHSV 2.3 h−1 and the predicted value of YA was 79.81%. The effect of each factor on YA was presented as follows: P > LHSV > WAIT. Compared to the catalytic reforming of petroleum-based naphtha, CDN catalytic reforming not only achieves higher YC5+ while achieving higher YA, but also obtains higher yield of benzene-toluene-xylene (YBTX, 60%). Second, the 17-lumped kinetic model of CDN semi-regenerative catalytic reforming reactor was established, and the model parameters of kinetic model were estimated and validated by Broyden-Fletcher-Goldfarb-Shanno algorithm. The results show that the simulation model is accurate, reliable and has good predictive ability. Third, the change regulation of reactants and temperature in the reforming reactor along the catalyst bed were simulated by using the 17-lumped kinetic model under specific operating conditions. [ABSTRACT FROM AUTHOR]