Publications by authors named "Yi Han"

577 Publications

Synthesis and Chiral Resolution of Twisted Carbon Nanobelts.

J Am Chem Soc 2021 Sep 22. Epub 2021 Sep 22.

Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore.

Twisted carbon nanobelts could display persistent chirality, which is desirable for material applications, but their synthesis is very challenging. Herein, we report the successful synthesis and chiral resolution of such a kind of molecules ( and ) with a figure-eight configuration. was synthesized first by macrocyclization through Suzuki coupling reaction followed by benzannulation via Bi(OTf)-mediated cyclization reaction of vinyl ether. Oxidative dehydrogenation of gave the fully π-conjugated . Their twisted structures were confirmed by X-ray crystallographic analysis and calculations, and they can be resolved by chiral high-performance liquid chromatography. The isolated enantiomers showed persistent chiroptical properties according to the circular dichroism measurements, with moderate || values (0.0016 for and 0.005-0.007 for ). Their photophysical properties were also briefly studied.
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http://dx.doi.org/10.1021/jacs.1c08468DOI Listing
September 2021

Neural dynamics underlying the acquisition of distinct auditory category structures.

Neuroimage 2021 Sep 17:118565. Epub 2021 Sep 17.

Department of Communication Science and Disorders, School of Health and Rehabilitation Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA; Center for the Neural Basis of Cognition, Pittsburgh, PA, 15232, USA. Electronic address:

Despite the multidimensional and temporally fleeting nature of auditory signals we quickly learn to assign novel sounds to behaviorally relevant categories. The neural systems underlying the learning and representation of novel auditory categories are far from understood. Current models argue for a rigid specialization of hierarchically organized core regions that are fine-tuned to extracting and mapping relevant auditory dimensions to meaningful categories. Scaffolded within a dual-learning systems approach, we test a competing hypothesis: the spatial and temporal dynamics of emerging auditory-category representations are not driven by the underlying dimensions but are constrained by category structure and learning strategies. To test these competing models, we used functional Magnetic Resonance Imaging (fMRI) to assess representational dynamics during the feedback-based acquisition of novel non-speech auditory categories with identical dimensions but differing category structures: rule-based (RB) categories, hypothesized to involve an explicit sound-to-rule mapping network, and information integration (II) based categories, involving pre-decisional integration of dimensions via a procedural-based sound-to-reward mapping network. Adults were assigned to either the RB (n = 30, 19 females) or II (n = 30, 22 females) learning tasks. Despite similar behavioral learning accuracies, learning strategies derived from computational modeling and involvements of corticostriatal systems during feedback processing differed across tasks. Spatiotemporal multivariate representational similarity analysis revealed an emerging representation within an auditory sensory-motor pathway exclusively for the II learning task, prominently involving the superior temporal gyrus (STG), inferior frontal gyrus (IFG), and posterior precentral gyrus. In contrast, the RB learning task yielded distributed neural representations within regions involved in cognitive-control and attentional processes that emerged at different time points of learning. Our results unequivocally demonstrate that auditory learners' neural systems are highly flexible and show distinct spatial and temporal patterns that are not dimension-specific but reflect underlying category structures and learning strategies.
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http://dx.doi.org/10.1016/j.neuroimage.2021.118565DOI Listing
September 2021

Isopsoralen ameliorates rheumatoid arthritis by targeting MIF.

Arthritis Res Ther 2021 Sep 17;23(1):243. Epub 2021 Sep 17.

Biomedical Sciences College & Shandong Medicinal Biotechnology Centre, Key lab for Biotech-Drugs of National Health Commission, Key Lab for Rare & Uncommon Diseases of Shandong Province, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, China.

Background: Isopsoralen (IPRN), one of the active ingredients of Psoralea corylifolia Linn, has anti-inflammatory properties. We attempted to investigate the inhibitory effects of IPRN on rheumatoid arthritis (RA) and characterize its potential mechanism.

Methods: RA fibroblast-like synoviocytes (FLSs) and mice with collagen-induced arthritis (CIA) were used as in vitro and in vivo models to analyze the antiarthritic effect of IPRN. Histological analysis of the inflamed joints from mice with CIA was performed using microcomputed tomography (micro-CT) and hematoxylin-eosin (HE) staining. RNA sequencing (RNA-Seq), network pharmacology analysis, molecular docking, drug affinity responsive target stability (DARTS) assay, and cellular thermal shift assay (CETSA) were performed to evaluate the targets of IPRN.

Results: IPRN ameliorated the inflammatory phenotype of RA FLSs by inhibiting their cytokine production, migration, invasion, and proangiogenic ability. IPRN also significantly reduced the severity of CIA in mice by decreasing paw thickness, arthritis score, bone damage, and serum inflammatory cytokine levels. A mechanistic study demonstrated that macrophage migration inhibitory factor (MIF), a key protein in the inflammatory process, was the specific target by which IPRN exerted its anti-inflammatory effects in RA FLSs.

Conclusion: Our study demonstrates the antiarthritic effect of IPRN, which suggests the therapeutic potential of IPRN in RA.
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http://dx.doi.org/10.1186/s13075-021-02619-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8447788PMC
September 2021

A real world cost-minimization analysis comparing the use of different endoscopic staplers in video-assisted thoracic surgery lobectomy procedures.

J Comp Eff Res 2021 Oct 15;10(14):1079-1088. Epub 2021 Sep 15.

Health Economics Research Institute, Sun Yat-Sen University, Guangdong Province, Guangzhou, China.

China's cost-containment measures increasingly focus solely on the prices of consumable medical supplies without taking a broader perspective on differences in features and overall costs. This study compared two types of endoscopic staplers in video-assisted thoracoscopic surgery (VATS) lobectomy. Electronic medical records for video-assisted thoracoscopic surgery from 2016 to 2017 were collected from a hospital in Anhui province. Two cohorts were retroactively defined based on stapler type. Total costs were compared using a cost-minimization analysis model. Probabilistic sensitivity analysis was performed. In the base case, the group using more expensive staplers achieved overall cost savings of about $300 per procedure. Sensitivity analysis confirmed this result in 86.5% of cases. A price-only supply selection strategy may have unintended cost consequences.
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http://dx.doi.org/10.2217/cer-2020-0287DOI Listing
October 2021

Learning nonnative speech sounds changes local encoding in the adult human cortex.

Proc Natl Acad Sci U S A 2021 Sep;118(36)

Department of Neurological Surgery, University of California, San Francisco, CA 94143;

Adults can learn to identify nonnative speech sounds with training, albeit with substantial variability in learning behavior. Increases in behavioral accuracy are associated with increased separability for sound representations in cortical speech areas. However, it remains unclear whether individual auditory neural populations all show the same types of changes with learning, or whether there are heterogeneous encoding patterns. Here, we used high-resolution direct neural recordings to examine local population response patterns, while native English listeners learned to recognize unfamiliar vocal pitch patterns in Mandarin Chinese tones. We found a distributed set of neural populations in bilateral superior temporal gyrus and ventrolateral frontal cortex, where the encoding of Mandarin tones changed throughout training as a function of trial-by-trial accuracy ("learning effect"), including both increases and decreases in the separability of tones. These populations were distinct from populations that showed changes as a function of exposure to the stimuli regardless of trial-by-trial accuracy. These learning effects were driven in part by more variable neural responses to repeated presentations of acoustically identical stimuli. Finally, learning effects could be predicted from speech-evoked activity even before training, suggesting that intrinsic properties of these populations make them amenable to behavior-related changes. Together, these results demonstrate that nonnative speech sound learning involves a wide array of changes in neural representations across a distributed set of brain regions.
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http://dx.doi.org/10.1073/pnas.2101777118DOI Listing
September 2021

Effects of water and nitrogen coupling on the photosynthetic characteristics, yield, and quality of Isatis indigotica.

Sci Rep 2021 Aug 30;11(1):17356. Epub 2021 Aug 30.

Yimin Irrigation Experimental Station, Minle County, Zhangye, 734500, China.

Isatis indigotica is a commercial medicinal crop that is widely cultivated with high water and nutrient application, in the arid areas of northwest China. Rational irrigation and nitrogen application are key factors for successful crop management. The objective of this study was to determine the effect of water and nitrogen coupling on the photosynthetic characteristics, yield, and quality of Isatis indigotica produced in northwestern China. Field trials were conducted for 2 consecutive years at an irrigation test station. Data on photosynthetic parameters, yield, and quality were collected from individual Isatis indigotica for each treatment during 2018-2019. The application of nitrogen significantly increased photosynthetic rates and yield under the same irrigation conditions. However, the yields were reduced in the excess water treatments (W3N1 and W3N2) and in the excess nitrogen treatments (W1N3, W2N3, and W3N3) in contrast to the optimum W2N2 treatment. Moreover, the quality indicators of the W2N2 treatment decreased compared with CK, which was due to water stress and more photoassimilates being available to the roots, but the effective quality index value could be effectively improved by greatly increasing the yield.
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http://dx.doi.org/10.1038/s41598-021-96747-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8405819PMC
August 2021

Facile Synthesis of a Fully Fused, Three-Dimensional π-Conjugated Archimedean Cage with Magnetically Shielded Cavity.

J Am Chem Soc 2021 Sep 29;143(35):14314-14321. Epub 2021 Aug 29.

Department of Chemistry, National University of Singapore, Singapore 117543.

The synthesis of molecular cages consisting of fully fused, π-conjugated rings is rare due to synthetic challenges including preorganization, large strain, and poor solubility. Herein, we report such an example in which a tris-2-aminobenzophenone precursor undergoes acid-mediated self-condensation to form a truncated tetrahedron, one of the 13 Archimedean solids. Formation of eight-membered [1,5]diazocine rings provides preorganization and releases the strain while still maintains weak π-conjugation of the backbone. Thorough characterizations were performed by X-ray, NMR, and UV-vis analysis, assisted by theoretical calculations. The cage exhibits a rigid backbone structure with a well-defined cavity that confines a magnetically shielded environment. The solvent molecule, -dichlorobenzene, is precisely encapsulated in the cavity at a 1:1 ratio with multiple π···π, C-H···π, and halogen···π interactions with the cage skeleton, implying its template effect for the cage closing reaction. Our synthetic strategy opens the opportunity to access more complex, fully fused, three-dimensional π-conjugated cages.
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http://dx.doi.org/10.1021/jacs.1c06490DOI Listing
September 2021

Revealing the heterogeneous activation mechanism of peroxydisulfate by CuO: the critical role of surface-binding organic substrates.

Sci Total Environ 2021 Aug 24;802:149833. Epub 2021 Aug 24.

School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China; CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China. Electronic address:

Heterogeneous catalytic activation mechanisms of peroxydisulfate (PDS) by transition metal oxides are generally attributed to the interactions between catalysts and PDS, however, the role of the co-existed organic substrate was largely overlooked in the past studies. In this work, phenol was selected as the target organic pollutant in a CuO/PDS system to evaluate its deep-seated role in participating in the effective activation of PDS. First, optimized reaction conditions as pH of 6.0, CuO of 5.96 g·L and PDS of 2.5 mM were obtained by the response surface methodology (RSM) with a phenol degradation efficiency of 84.0%. It was further found that pre-adsorption of phenol or PDS led to obviously different performances in the phenol degradation with/without the radical scavengers. Two different activation pathways of PDS, i.e., the non-radical pathway mediated by surface deprotonated phenol to generate O and the radical pathway mediated by structural Cu(I)/Cu(II) to produce SO, were therefore proposed, and the former was predominant in the CuO/PDS/phenol system. In addition, HCO and HPO could strongly inhibit the phenol degradation while Cl and NO only performed negligible effects. NaOH washing could regenerate the surface hydroxyl groups and recover the catalytic ability of CuO. The result of this study integrated the interactions among the catalyst, oxidant and substrate, providing new insights into environmental-friendly PDS activation processes.
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http://dx.doi.org/10.1016/j.scitotenv.2021.149833DOI Listing
August 2021

AgentDress: Realtime Clothing Synthesis for Virtual Agents using Plausible Deformations.

IEEE Trans Vis Comput Graph 2021 Aug 27;PP. Epub 2021 Aug 27.

We present a CPU-based real-time cloth animation method for dressing virtual humans of various shapes and poses. Our approach formulates the clothing deformation as a high-dimensional function of body shape parameters and pose parameters. In order to accelerate the computation, our formulation factorizes the clothing deformation into two independent components: the deformation introduced by body pose variation (Clothing Pose Model) and the deformation from body shape variation (Clothing Shape Model). Furthermore, we sample and cluster the poses spanning the entire pose space and use those clusters to efficiently calculate the anchoring points. We also introduce a sensitivity-based distance measurement to both find nearby anchoring points and evaluate their contributions to the final animation. Given a query shape and pose of the virtual agent, we synthesize the resulting clothing deformation by blending the Taylor expansion results of nearby anchoring points. Compared to previous methods, our approach is general and able to add the shape dimension to any clothing pose model. Furthermore, we can animate clothing represented with tens of thousands of vertices at 50+ FPS on a CPU. We also conduct a user evaluation and show that our method can improve a user's perception of dressed virtual agents in an immersive virtual environment (IVE) compared to a realtime linear blend skinning method.
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http://dx.doi.org/10.1109/TVCG.2021.3106429DOI Listing
August 2021

Deep Reinforcement Learning for Combinatorial Optimization: Covering Salesman Problems.

IEEE Trans Cybern 2021 Aug 26;PP. Epub 2021 Aug 26.

This article introduces a new deep learning approach to approximately solve the covering salesman problem (CSP). In this approach, given the city locations of a CSP as input, a deep neural network model is designed to directly output the solution. It is trained using the deep reinforcement learning without supervision. Specifically, in the model, we apply the multihead attention (MHA) to capture the structural patterns, and design a dynamic embedding to handle the dynamic patterns of the problem. Once the model is trained, it can generalize to various types of CSP tasks (different sizes and topologies) without the need of retraining. Through controlled experiments, the proposed approach shows desirable time complexity: it runs more than 20 times faster than the traditional heuristic solvers with a tiny gap of optimality. Moreover, it significantly outperforms the current state-of-the-art deep learning approaches for combinatorial optimization in the aspect of both training and inference. In comparison with traditional solvers, this approach is highly desirable for most of the challenging tasks in practice that are usually large scale and require quick decisions.
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http://dx.doi.org/10.1109/TCYB.2021.3103811DOI Listing
August 2021

Expanded Kekulenes.

J Am Chem Soc 2021 Sep 20;143(34):13908-13916. Epub 2021 Aug 20.

Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.

The synthesis of kekulene and its higher homologues is a challenging task in organic chemistry. The first successful synthesis and characterization of the parent kekulene were reported by Diederich and Staab in 1978. Herein, we report the facile preparation of a series of edge-extended kekulenes by bismuth(III) triflate-catalyzed cyclization of vinyl ethers from the properly designed macrocyclic precursors. Their molecular structures were confirmed by X-ray crystallographic analysis and NMR spectroscopy. Their size- and symmetry-dependent electronic structures (frontier molecular orbitals, aromaticity) and physical properties (optical and electrochemical) were investigated by various spectroscopic measurements, assisted by theoretical calculations. Particularly, the acene-like units along each zigzag edge demonstrate a dominant local aromatic character. Our studies provide an easy synthetic strategy toward various fully fused carbon nanostructures and give some insights into the electronic properties of cycloarenes.
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http://dx.doi.org/10.1021/jacs.1c06757DOI Listing
September 2021

[Prognostic risk factors of patients with sepsis and the clinical characteristics of patients with septic myocardial injury].

Zhonghua Wei Zhong Bing Ji Jiu Yi Xue 2021 Jul;33(7):809-814

Department of Emergency, Zhongshan Hospital, Fudan University, Shanghai 200032, China. Corresponding author: Yao Chenling, Email:

Objective: To analyze the prognostic risk factors of patients with sepsis and the clinical characteristics of patients with septic myocardial injury.

Methods: A retrospective study was conducted. The clinical data of 300 patients with sepsis admitted to emergency department of Zhongshan Hospital of Fudan University from September 2017 to June 2020 were enrolled, including basic information, blood test indicators and auxiliary inspection indicators. The patients were grouped according to myocardial injury and the clinical characteristics of patients with septic myocardial injury were analyzed. According to 28-day prognosis, they were divided into survival group and non-survival group. The differences in various indicators between the two groups were compared, and binary Logistic regression was used to explore independent risk factors for death in patients with sepsis.

Results: In 300 patients, 47 patients were excluded for previous heart disease or lack of the main inspections, and 253 patients were enrolled finally. (1) Myocardial injury occurred in 136 out of 253 patients (53.8%), and 117 without myocardial injury. Compared with the non-myocardial injury group, the myocardial injury group had higher blood white blood cell count [WBC (×10/L): 9.7 (6.7, 13.4) vs. 8.3 (5.4, 12.2)] and procalcitonin [PCT (μg/L): 0.61 (0.18, 4.63) vs. 0.23 (0.09, 0.99)] at admission, and more Staphylococcal infections (17.6% vs. 2.6%), more arrhythmia (sinus tachycardia: 30.9% vs. 23.1%), more ST-T changes (26.5% vs. 23.1%), lower left ventricular ejection fraction [LVEF: 0.60 (0.54, 0.65) vs. 0.62 (0.60, 0.66)], higher pulmonary artery systolic pressure [PASP (mmHg, 1 mmHg = 0.133 kPa): 38.0 (32.2, 46.0) vs. 33.0 (30.0, 40.2)], and worse prognosis (28-day mortality: 44.1% vs. 6.0%, all P < 0.05). Logistic regression analysis showed that PCT increased [odds ratio (OR) = 1.039, 95% confidence interval (95%CI) was 1.018-1.060, P < 0.01], LVEF decreased (OR = 0.828, 95%CI was 0.729-0.941, P < 0.01) and sinus tachycardia (OR = 3.512, 95%CI was 1.417-8.702, P < 0.01) were clinical characteristics of septic patients with myocardial injury. (2) A total of 186 of the 253 patients survived, and 67 died with 28-day mortality of 26.5%. Compared with the survival group, non-survival group had higher myocardial markers and inflammation markers at admission [cardiac troponin T (cTnT, μg/L): 0.06 (0.02, 0.17) vs. 0.02 (0.01, 0.05), N-terminal pro-brain natriuretic peptide (NT-proBNP, ng/L): 3 037.0 (1 308.7, 12 033.7) vs. 893.9 (272.8, 2 825.5), creatine kinase (CK, U/L): 144.5 (57.5, 660.8) vs. 89.5 (47.8, 201.0), WBC (×10/L): 10.5 (6.7, 14.6) vs. 8.6 (6.0, 12.0), C-reactive protein (CRP, mg/L): 89.2 (54.8, 128.5) vs. 63.8 (19.3, 105.6), PCT (μg/L): 2.13 (0.31, 11.79) vs. 0.28 (0.10, 1.25), all P < 0.05], and more sinus tachycardia and atrial arrhythmia (41.8% vs. 22.0%, 29.9% vs. 17.7%, both P < 0.05). Logistic regression analysis showed that cTnT increased (OR = 2.115, 95%CI was 1.189-5.459, P < 0.05), sinus tachycardia (OR = 2.557, 95%CI was 1.103-5.929, P < 0.05) and atrial arrhythmia (OR = 2.474, 95%CI was 1.025-5.969, P < 0.05) were independent risk factors for 28-day death in patients with sepsis.

Conclusions: Myocardial injury is an independent risk factor for death in patients with sepsis. PCT elevation, LVEF decreased and sinus tachycardia are main characteristics of patients with septic myocardial injury, which should attract clinical attention.
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http://dx.doi.org/10.3760/cma.j.cn121430-20201225-00774DOI Listing
July 2021

The characteristics and implications of epidemic reports during COVID-19 in the United States.

J Biosaf Biosecur 2021 Dec 11;3(2):72-75. Epub 2021 Aug 11.

Naval Medical Center of PLA, 880 Xiangyin Road, Yangpu District, Shanghai, China.

We summarized the basic practices and characteristics of epidemic reporting during the COVID-19 pandemic in the United States. Based on the analysis of the advantages and disadvantages of epidemic data reporting, we put forward some suggestions that should be used for reference and thus improve the epidemic data reports of infectious diseases.
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http://dx.doi.org/10.1016/j.jobb.2021.07.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8354790PMC
December 2021

Predictive Significance of the Prognostic Nutritional Index (PNI) in Patients with Severe COVID-19.

J Immunol Res 2021 9;2021:9917302. Epub 2021 Jul 9.

Department of Emergency Medicine, Zhongshan Hospital, Fudan University, Shanghai, China.

Background: The prognostic nutritional index (PNI) has been reported to significantly correlate with poor survival and postoperative complications in patients with various diseases, but its relationship with mortality in COVID-19 patients has not been addressed.

Method: A multicenter retrospective study involving patients with severe COVID-19 was conducted to investigate whether malnutrition and other clinical characteristics could be used to stratify the patients based on risk.

Results: A total of 395 patients were included in our study, with 236 patients in the training cohort, 59 patients in the internal validation cohort, and 100 patients in the external validation cohort. During hospitalization, 63/236 (26.69%) and 14/59 (23.73%) patients died in the training and validation cohorts, respectively. PNI had the strongest relationships with the neutrophil-lymphocyte ratio (NLR) and lactate dehydrogenase (LDH) level but was less strongly correlated with the CURB65, APACHE II, and SOFA scores. The baseline PNI score, platelet (PLT) count, LDH level, and PaO/FiO (P/F) ratio were independent predictors of mortality in COVID-19 patients. A nomogram incorporating these four predictors showed good calibration and discrimination in the derivation and validation cohorts. A PNI score less than 33.405 was associated with a higher risk of mortality in severe COVID-19 patients in the Cox regression analysis.

Conclusion: These findings have implications for predicting the risk of mortality in COVID-19 patients at the time of admission and provide the first direct evidence that a lower PNI is related to a worse prognosis in severe COVID-19 patients.
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http://dx.doi.org/10.1155/2021/9917302DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8279875PMC
August 2021

A Review of Intelligent Driving Pedestrian Detection Based on Deep Learning.

Comput Intell Neurosci 2021 20;2021:5410049. Epub 2021 Jul 20.

School of Computer Science and Engineering, Xi'an University of Technology, Xi'an, Shaanxi 710048, China.

Pedestrian detection is a specific application of object detection. Compared with general object detection, it shows similarities and unique characteristics. In addition, it has important application value in the fields of intelligent driving and security monitoring. In recent years, with the rapid development of deep learning, pedestrian detection technology has also made great progress. However, there still exists a huge gap between it and human perception. Meanwhile, there are still a lot of problems, and there remains a lot of room for research. Regarding the application of pedestrian detection in intelligent driving technology, it is of necessity to ensure its real-time performance. Additionally, it is necessary to lighten the model while ensuring detection accuracy. This paper first briefly describes the development process of pedestrian detection and then concentrates on summarizing the research results of pedestrian detection technology in the deep learning stage. Subsequently, by summarizing the pedestrian detection dataset and evaluation criteria, the core issues of the current development of pedestrian detection are analyzed. Finally, the next possible development direction of pedestrian detection technology is explained at the end of the paper.
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http://dx.doi.org/10.1155/2021/5410049DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8318761PMC
August 2021

Cyclobis[2,5-(thiophenedimethane)-4,4'-(triphenylamine)] versus Its ,-Dioxidized Macrocycle: Global Antiaromaticity and Intramolecular Dynamics.

Org Lett 2021 Aug 30;23(16):6382-6386. Epub 2021 Jul 30.

Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543.

Fully conjugated macrocycles containing benzenoid rings rarely show global aromaticity/antiaromaticity. Herein, we report an annulene-like macrocycle and its ,-dioxidized macrocycle with alternative quinoidal thiophene/1,1-dioxide thiophene and triphenyl amine moieties. They both showed temperature-dependent intramolecular dynamics and global antiaromatic character with 32π electrons at low temperature. However, and have different conjugated pathways.
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http://dx.doi.org/10.1021/acs.orglett.1c02200DOI Listing
August 2021

Persistent deficiency of mucosa-associated invariant T (MAIT) cells during alcohol-related liver disease.

Cell Biosci 2021 Jul 28;11(1):148. Epub 2021 Jul 28.

Department of Oncology, the First Affiliated Hospital of Anhui Medical University, Hefei, 230032, Anhui, China.

Background: Alcohol-related liver disease (ALD) is a major cause of chronic liver diseases. Inflammatory response is a basic pathological feature of ALD. Mucosal-associated invariant T(MAIT) cells are a novel population of innate immune cells, which may be depleted in various inflammatory diseases. However, the changes of MAIT cell in ALD remains unclear.

Results: In this study, the levels of MAIT cell were significantly decreased in patients with alcoholic fatty liver disease, alcoholic cirrhosis, and mixed cirrhosis (alcoholic + viral). Furthermore, the reduction of circulating MAIT cells was correlated with liver function in patients with cirrhosis. Functional changes among circulating MAIT cells in patients with alcoholic cirrhosis, including increased production of IL-17A and perforin, and reduced production of TNF-α. Plasma cytokine and chemokine levels were quantified using multiple immunoassays and ELISA. Serum levels of chemokine IL-8 were correlated with MAIT cell frequency in patients with alcoholic cirrhosis. Moreover, no differences were observed in the expression of CCR6, CXCR6, and PD-1 in circulating MAIT cells of patients with alcoholic cirrhosis. The MAIT cells in patients with alcoholic cirrhosis were prone to apoptosis, which was promoted by IL-12, IL-18, and IL-8.

Conclusions: Our findings indicate persistent MAIT cell loss during alcohol-related liver disease and suggest that MAIT cells can be promising indicator and therapeutic targets in ALD.
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http://dx.doi.org/10.1186/s13578-021-00664-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8320031PMC
July 2021

S-nitrosylation-mediated coupling of G-protein alpha-2 with CXCR5 induces Hippo/YAP-dependent diabetes-accelerated atherosclerosis.

Nat Commun 2021 07 22;12(1):4452. Epub 2021 Jul 22.

Key Laboratory of Cardiovascular and Cerebrovascular Medicine, Nanjing Medical University, Nanjing, China.

Atherosclerosis-associated cardiovascular disease is one of the main causes of death and disability among patients with diabetes mellitus. However, little is known about the impact of S-nitrosylation in diabetes-accelerated atherosclerosis. Here, we show increased levels of S-nitrosylation of guanine nucleotide-binding protein G(i) subunit alpha-2 (SNO-GNAI2) at Cysteine 66 in coronary artery samples from diabetic patients with atherosclerosis, consistently with results from mice. Mechanistically, SNO-GNAI2 acted by coupling with CXCR5 to dephosphorylate the Hippo pathway kinase LATS1, thereby leading to nuclear translocation of YAP and promoting an inflammatory response in endothelial cells. Furthermore, Cys-mutant GNAI2 refractory to S-nitrosylation abrogated GNAI2-CXCR5 coupling, alleviated atherosclerosis in diabetic mice, restored Hippo activity, and reduced endothelial inflammation. In addition, we showed that melatonin treatment restored endothelial function and protected against diabetes-accelerated atherosclerosis by preventing GNAI2 S-nitrosylation. In conclusion, SNO-GNAI2 drives diabetes-accelerated atherosclerosis by coupling with CXCR5 and activating YAP-dependent endothelial inflammation, and reducing SNO-GNAI2 is an efficient strategy for alleviating diabetes-accelerated atherosclerosis.
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http://dx.doi.org/10.1038/s41467-021-24736-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8298471PMC
July 2021

Periodic root branching is influenced by light through an HY1-HY5-auxin pathway.

Curr Biol 2021 Sep 19;31(17):3834-3847.e5. Epub 2021 Jul 19.

MOA Key Laboratory of Plant Nutrition and Fertilization in Lower-Middle Reaches of the Yangtze River and State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing 210095, China. Electronic address:

The spacing of lateral roots (LRs) along the main root in plants is driven by an oscillatory signal, often referred to as the "root clock" that represents a pre-patterning mechanism that can be influenced by environmental signals. Light is an important environmental factor that has been previously reported to be capable of modulating the root clock, although the effect of light signaling on the LR pre-patterning has not yet been fully investigated. In this study, we reveal that light can activate the transcription of a photomorphogenic gene HY1 to maintain high frequency and amplitude of the oscillation signal, leading to the repetitive formation of pre-branch sites. By grafting and tissue-specific complementation experiments, we demonstrated that HY1 generated in the shoot or locally in xylem pole pericycle cells was sufficient to regulate LR branching. We further found that HY1 can induce the expression of HY5 and its homolog HYH, and act as a signalosome to modulate the intracellular localization and expression of auxin transporters, in turn promoting auxin accumulation in the oscillation zone to stimulate LR branching. These fundamental mechanistic insights improve our understanding of the molecular basis of light-controlled LR formation and provide a genetic interconnection between shoot- and root-derived signals in regulating periodic LR branching.
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http://dx.doi.org/10.1016/j.cub.2021.06.055DOI Listing
September 2021

Inhibition of HSP90 S-nitrosylation Alleviates Cardiac Fibrosis via TGFβ/SMAD3 Signaling Pathway.

Br J Pharmacol 2021 Jul 15. Epub 2021 Jul 15.

Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Nanjing Medical University, Nanjing, China.

Background And Purpose: Effective anti-fibrotic therapeutic solutions are unavailable so far. The heat shock protein 90 (HSP90) exerts deleterious effects in some fibrotic diseases. S-nitrosylation (SNO) of HSP90 affects its own function, however, little is known about its role in pathological stress. Here, we investigated the effect of SNO-HSP90 on cardiac fibrosis.

Experimental Approach: SNO-HSP90 level was measured by biotin-switch. SNO sites were identified through mass spectrometry. S-nitrosylation site-mutated plasmids or adeno-associated virus, gene deletion and pharmacological antagonists were used to identify the contribution of SNO-HSP90 in myocardial fibrosis.

Key Results: SNO-HSP90 level was positively correlated with fibrosis marker expression in hearts from patients and significantly higher in fibrotic hearts from spontaneously hypertensive rats and mice subjected to transverse aortic constriction, as well as in angiotensin II- or isoproterenol-treated neonatal rat cardiac fibroblasts. S-nitrosylated site of HSP90 at cysteine 589 was identified. Inhibition of SNO-HSP90 by Cys589 mutation reduced fibrosis in angiotensin II- or isoproterenol-treated cardiac fibroblasts. Administration of recombinant adeno-associated virus of Cys589 mutation improved heart function and alleviated fibrosis in transverse aortic constriction mice. Mechanismly, SNO-HSP90 stimulated transforming growth factor-β type II receptor (TGFβ RII) binding to HSP90 in response to fibrotic stimuli, subsequently increased phosphorylation and nuclear translocation of SMAD3. Additionally, inducible nitric oxide synthase (iNOS) deficiency or iNOS inhibitor, 1400W, reduced SNO-HSP90 level and the activation of TGFβ/SMAD3 signaling pathway.

Conclusions And Implications: We demonstrate that genetic or pharmacological inhibition of SNO-HSP90 mitigates fibrosis through blocking TGFβ/SMAD3 signaling pathway, providing a potential therapy for cardiac remodeling.
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http://dx.doi.org/10.1111/bph.15626DOI Listing
July 2021

Enhanced sludge dewaterability by Fe-rich biochar activating hydrogen peroxide: Co-hydrothermal red mud and reed straw.

J Environ Manage 2021 Oct 9;296:113239. Epub 2021 Jul 9.

School of Resource and Environmental Science, Wuhan University, Wuhan, 430072, Hubei, China; College of Resources and Environment, Anqing Normal University, Anqing, 246011, Anhui, China. Electronic address:

This study proposed Fe-rich biochar (RMRS-BC) produced by the co-hydrothermal treatment of red mud and reed straw, industrial waste and agricultural waste, as a novel sludge conditioner. It had been proven that heterogeneous and homogeneous Fenton reactions occurred during the sludge conditioning process, in which RMRS-BC activated HO to improve sludge dewaterability. Results demonstrated that the optimal condition was 7.5 wt% dry solids (DS) of RMRS-BC at a mass ratio of 1:1 combined with HO. The corresponding water content of sludge cakes and the capillary suction time reduction efficiency were 57.88 wt% and 69.76%, respectively. The FeO supported in the RMRS-BC structure was used as a catalyst to produce heterogeneous reaction, and the Fe leached from the RMRS-BC after acidification happened homogeneous reaction. Double Fenton reaction in sludge conditioning enhanced the production efficiency of ·OH, the sludge flocs were dispersed into smaller particles, more bound water from the extracellular polymeric substances (EPS) was released, and sludge dewaterability performance was improved. Another main mechanism for enhancing dewaterability was to use RMRS-BC as a skeleton builder to reduce the compressibility of sludge cakes and facilitated free water to flow out. In summary, the Fenton oxidation method activated by RMRS-BC is feasible in improving sludge dewatering.
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http://dx.doi.org/10.1016/j.jenvman.2021.113239DOI Listing
October 2021

Solvent-free microwave synthesis of ultra-small [email protected] with strong metal-support interaction for industrial hydrogen evolution.

Nat Commun 2021 Jun 29;12(1):4018. Epub 2021 Jun 29.

Key Laboratory of Eco-chemical Engineering, Key Laboratory of Optic-electric Sensing and Analytical Chemistry of Life Science, Taishan Scholar Advantage and Characteristic Discipline Team of Eco Chemical Process and Technology, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, P. R. China.

Exploring a simple, fast, solvent-free synthetic method for large-scale preparation of cheap, highly active electrocatalysts for industrial hydrogen evolution reaction is one of the most promising work today. In this work, a simple, fast and solvent-free microwave pyrolysis method is used to synthesize ultra-small (3.5 nm) [email protected] catalyst with heterogeneous structure and strong metal-support interaction in one step. The [email protected] catalyst only exhibits an overpotential of 15 mV at a current density of 10 mA cm, and exhibits a large turnover frequency value up to 21.9 s under an overpotential of 100 mV in 1.0 M KOH. In addition, this catalyst can reach high current densities of 500 mA cm and 1000 mA cm at low overpotentials of 56 mV and 78 mV respectively, and it displays high stability of 1000 h. This work provides a feasible way for the reasonable design of other large-scale production catalysts.
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http://dx.doi.org/10.1038/s41467-021-24322-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8242096PMC
June 2021

Perchlorate bioreduction in UASB reactor: S-autotrophic granular sludge formation and sulphate generation control.

Environ Technol 2021 Jul 9:1-11. Epub 2021 Jul 9.

School of Environmental and Municipal Engineering, Tianjin Key Laboratory of Aquatic Science and Technology, Tianjin Chengjian University, Tianjin, People's Republic of China.

Perchlorate () industrial wastewater requires efficient removal to prevent adverse environmental impacts, however, high concentration and low biodegradability give rise to poor bioreduction performance. -autotrophic granular sludge (-AuGS) was firstly cultivated for high concentration perchlorate () removal in the upflow anaerobic sludge blanket (UASB) reactor (: 150 mg L). Simultaneously, the was utilized to control the generation as electron donor, the effluent concentration (190 mg L) was satisfied with drinking water standard (250 mg L). Under the optimized condition of hydraulic retention time (HRT) (6 h) and / molar ratio (2.2), more EPS was secreted, which promoted the -AuGS formation and stability. Though acclimation of 146 d, the -AuGS was formed with a large average granular sludge size (612 μm) and an excellent settleability (sludge volume index: SVI/SVI= 1). With the mature -AuGS formation, the highest and loading was increased to 1.06 and 0.75 kg m d. Interestingly, , , and were the main microbial community in the -AuGS. This study proposed to form a novel -AuGS for developing the high concentration removal performance and to utilize the as an electron donor for controlling the excessive generation.
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http://dx.doi.org/10.1080/09593330.2021.1949046DOI Listing
July 2021

Artificial Synapses Based on Ferroelectric Schottky Barrier Field-Effect Transistors for Neuromorphic Applications.

ACS Appl Mater Interfaces 2021 Jul 25;13(27):32005-32012. Epub 2021 Jun 25.

Peter Grünberg Institute (PGI 9) and JARA-Fundamentals of Future Information Technologies, Forschungszentrum Jülich GmbH, 52428 Jülich, Germany.

Artificial synapses based on ferroelectric Schottky barrier field-effect transistors (FE-SBFETs) are experimentally demonstrated. The FE-SBFETs employ single-crystalline NiSi contacts with an atomically flat interface to Si and HfZrO ferroelectric layers on silicon-on-insulator substrates. The ferroelectric polarization switching dynamics gradually modulate the NiSi/Si Schottky barriers and the potential of the channel, thus programming the device conductance with input voltage pulses. The short-term synaptic plasticity is characterized in terms of excitatory/inhibitory post-synaptic current (EPSC) and paired-pulse facilitation/depression. The EPSC amplitude shows a linear response to the amplitude of the pre-synaptic spike. Very low energy/spike consumption as small as ∼2 fJ is achieved, demonstrating high energy efficiency. Long-term potentiation/depression results show very high endurance and very small cycle-to-cycle variations (∼1%) after 10 pulse measurements. Furthermore, spike-timing-dependent plasticity is also emulated using the gate voltage pulse as the pre-synaptic spike and the drain voltage pulse as the post-synaptic spikes. These findings indicate that FE-SBFET synapses have high potential for future neuromorphic computing applications.
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http://dx.doi.org/10.1021/acsami.1c07505DOI Listing
July 2021

Digestive properties and effects of Chimonanthus nitens Oliv polysaccharides on antioxidant effects in vitro and in immunocompromised mice.

Int J Biol Macromol 2021 Aug 22;185:306-316. Epub 2021 Jun 22.

Key Lab for Agro-product Processing and Quality Control of Nanchang City, College of Food Science and Engineering, Jiangxi Agricultural University, Nanchang 330045, China. Electronic address:

The study was aimed to investigate the simulated digestion behavior of the bioactive polysaccharides from Chimonanthus nitens Oliv (COP1), antioxidant activity in vitro, and prevention against cyclophosphamide (CP) induced oxidative damage in mice. The results showed that COP1 were 18.843 kDa, and consisted of arabinose (56.6 mol%), galactose (24.9 mol%), xylose (11.1 mol%), and glucose (7.4 mol%). Gastrointestinal digestion significantly improved the radical (DPPH, OH, and ABTS) scavenging activities of COP1. Meanwhile, administration of COP1 (150, 300, and 600 mg/kg, continuous 16 days) prevented hepatotoxicity in CP-induced mice (reducing liver index and transaminase levels, alleviating liver damage). COP1 also attenuated oxidative stress as evident from as shown by reduced levels of MDA and enhanced activity of antioxidant enzymes (CAT, SOD, and GSH-Px). In addition, COP1 regulated the Nrf2/Keap1 signaling pathway in CP-treated mice, decreasing the upstream factor Keap1 and increasing the upstream factor Nrf2, which in turn enhanced the expression of downstream factors (NQO1, HO-1, GSH-Px, SOD1, and CAT). COP1 also protected the body from CP-induced oxidative damage by down-regulating Bax and caspase3 in the apoptosis pathway and up-regulating Bcl-2 mRNA levels. Overall, COP1 might be harnessed as an effective natural antioxidant for medical and food industries.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.06.114DOI Listing
August 2021

A cyclopenta-fused dibenzo[,]thiophene--phenanthrene macrocyclic tetraradicaloid.

Chem Sci 2021 Jan 26;12(11):3952-3957. Epub 2021 Jan 26.

Department of Materials Science, Fudan University Shanghai 200438 China

A cyclopenta-fused macrocyclic tetraradicaloid, , containing alternating phenanthrene (Phen) and dibenzo[,]thiophene (DBTh) units was synthesized and isolated in single-crystal form. Compared with its all-carbon isoelectronic structure, , the incorporation of two sulfur atoms leads to a smaller radical character and a larger singlet-triplet energy gap. X-ray crystallographic analysis reveals that the spin-spin coupling through the DBTh unit is stronger than that through the Phen moiety. In addition, the electron-rich sulfur atoms also raise the energies of both the HOMO and LUMO in , but the overall optical and electronic energy gaps are close to that of the . displays global anti-aromaticity according to the NMR measurements and theoretical calculations (NICS, ACID and 2D ICSS), with a 36π ring current circuit along the all-carbon periphery excluding the two sulphur atoms. Its dication becomes globally aromatic due to the existence of a dominant 34π-conjugation pathway. This study sheds some light on the effect of heteroatoms on the electronic properties of open-shell polyradicaloids.
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http://dx.doi.org/10.1039/d0sc06185aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8179481PMC
January 2021

HINT1 (Histidine Triad Nucleotide-Binding Protein 1) Attenuates Cardiac Hypertrophy Via Suppressing HOXA5 (Homeobox A5) Expression.

Circulation 2021 Aug 8;144(8):638-654. Epub 2021 Jun 8.

Key Laboratory of Targeted Intervention of Cardiovascular Disease, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Key Laboratory of Cardiovascular and Cerebrovascular Medicine (Y.Z., Q.D., S.C., K.Y., Z.S., Q.M., C.L., L.H., S.S., Feng Chen, MD, PhD, Y.G., H.C., L.X., Y.J.).

Background: Cardiac hypertrophy is an important prepathology of, and will ultimately lead to, heart failure. However, the mechanisms underlying pathological cardiac hypertrophy remain largely unknown. This study aims to elucidate the effects and mechanisms of HINT1 (histidine triad nucleotide-binding protein 1) in cardiac hypertrophy and heart failure.

Methods: HINT1 was downregulated in human hypertrophic heart samples compared with nonhypertrophic samples by mass spectrometry analysis. knockout mice were challenged with transverse aortic constriction surgery. Cardiac-specific overexpression of HINT1 mice by intravenous injection of adeno-associated virus 9 (AAV9)-encoding under the cTnT (cardiac troponin T) promoter were subjected to transverse aortic construction. Unbiased transcriptional analyses were used to identify the downstream targets of HINT1. AAV9 bearing shRNA against (homeobox A5) was administrated to investigate whether the effects of HINT1 on cardiac hypertrophy were HOXA5-dependent. RNA sequencing analysis was performed to recapitulate possible changes in transcriptome profile.Coimmunoprecipitation assays and cellular fractionation analyses were conducted to examine the mechanism by which HINT1 regulates the expression of HOXA5.

Results: The reduction of HINT1 expression was observed in the hearts of hypertrophic patients and pressure overloaded-induced hypertrophic mice, respectively. In -deficient mice, cardiac hypertrophy deteriorated after transverse aortic construction. Conversely, cardiac-specific overexpression of HINT1 alleviated cardiac hypertrophy and dysfunction. Unbiased profiler polymerase chain reaction array showed HOXA5 is 1 target for HINT1, and the cardioprotective role of HINT1 was abolished by HOXA5 knockdown in vivo. Hoxa5 was identified to affect hypertrophy through the TGF-β (transforming growth factor β) signal pathway. Mechanically, HINT1 inhibited PKCβ1 (protein kinase C β type 1) membrane translocation and phosphorylation via direct interaction, attenuating the MEK/ERK/YY1 (mitogen-activated protein kinase/extracellular signal-regulated kinase kinase/yin yang 1) signal pathway, downregulating HOXA5 expression, and eventually attenuating cardiac hypertrophy.

Conclusions: HINT1 protects against cardiac hypertrophy through suppressing HOXA5 expression. These findings indicate that HINT1 may be a potential target for therapeutic interventions in cardiac hypertrophy and heart failure.
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http://dx.doi.org/10.1161/CIRCULATIONAHA.120.051094DOI Listing
August 2021

H/CO separations in multicomponent metal-adeninate MOFs with multiple chemically distinct pore environments.

Chem Sci 2020 Oct 15;11(47):12807-12815. Epub 2020 Oct 15.

Department of Chemistry, University of Pittsburgh Pittsburgh PA 15260 USA

Metal-organic frameworks constructed from multiple (≥3) components often exhibit dramatically increased structural complexity compared to their 2 component (1 metal, 1 linker) counterparts, such as multiple chemically unique pore environments and a plurality of diverse molecular diffusion pathways. This inherent complexity can be advantageous for gas separation applications. Here, we report two isoreticular multicomponent MOFs, bMOF-200 (4 components; Cu, Zn, adeninate, pyrazolate) and bMOF-201 (3 components; Zn, adeninate, pyrazolate). We describe their structures, which contain 3 unique interconnected pore environments, and we use Kohn-Sham density functional theory (DFT) along with the climbing image nudged elastic band (CI-NEB) method to predict potential H/CO separation ability of bMOF-200. We examine the H/CO separation performance using both column breakthrough and membrane permeation studies. bMOF-200 membranes exhibit a H/CO separation factor of 7.9. The pore space of bMOF-201 is significantly different than bMOF-200, and one molecular diffusion pathway is occluded by coordinating charge-balancing formate and acetate anions. A consequence of this structural difference is reduced permeability to both H and CO and a significantly improved H/CO separation factor of 22.2 compared to bMOF-200, which makes bMOF-201 membranes competitive with some of the best performing MOF membranes in terms of H/CO separations.
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http://dx.doi.org/10.1039/d0sc04979dDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8163211PMC
October 2020

Highly efficient ratiometric nanothermometers based on colloidal carbon quantum dots.

J Mater Chem B 2021 05;9(20):4111-4119

College of Life Sciences, Qingdao University, No. 308 Ningxia Road, Qingdao 266071, P. R. China.

Optical nanothermometers have attracted much attention due to their non-contact and precise measurement with high spatial resolution at the micro- and nanoscales. They can be applied in various fields such as micro-opto-electronics, photonics, and biomedical thermal and pH sensing, while most thermal sensors reported so far contain heavy metals or have low sensitivity. Herein, we demonstrate a highly sensitive ratiometric thermal sensor based on colloidal C-dots. C-dots exhibit dual emission originating from the band gap emission and surface-dominant emission, which show a different temperature-dependent photoluminescence (PL) response. Among different surface-functionalized C-dots, [email protected] exhibit an absolute thermal sensitivity of -0.082 °C-1, which is the highest among various types of ratiometric thermosensors, making it a very promising candidate for high-sensitivity, self-calibrated nanoscale thermometry. As a proof-of-concept, [email protected] were employed to monitor the intracellular temperature (32-42 °C), showing a clear trend for temperature variation in a single cell, indicating that C-dots could offer a powerful tool for a potential precise measurement of the intracellular temperature. They could also be used as thermal sensors for nano-electronic and optoelectronic devices.
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http://dx.doi.org/10.1039/d1tb00224dDOI Listing
May 2021

Facet-controlled palladium nanocrystalline for enhanced nitrate reduction towards ammonia.

J Colloid Interface Sci 2021 Oct 14;600:620-628. Epub 2021 May 14.

Key Laboratory of Eco-chemical Engineering, Key Laboratory of Optic-electric Sensing and Analytical Chemistry of Life Science, Taishan Scholar Advantage and Characteristic Discipline Team of Eco Chemical Process and Technology, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China; Shandong Engineering Research Center for Marine Environment Corrosion and Safety Protection, College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China. Electronic address:

Electrochemical nitrate reduction reaction (NORR) is considered an appealing way for producing ammonia (NH) under ambient conditions and solving environmental problems caused by nitrate, whereas the lack of adequate catalysts hampers the development of NORR. Here, we firstly demonstrate that the Pd nanocrystalline with a well-desired facet can act as a highly efficient NORR electrocatalyst for ambient ammonia synthesis. Pd (1 1 1) exhibits excellent activity and selectivity in reducing NO to NH with a Faradaic efficiency of 79.91% and an NH production of 0.5485 mmol h cm (2.74 mmol h mg) in 0.1 M NaSO (containing 0.1 M NO), which is 1.4 times higher than Pd (1 0 0) and 1.9 times higher than Pd (1 1 0), respectively. Density functional theory (DFT) calculation reveals that the superior NORR activity of Pd (1 1 1) originates from its optimized activity of NO adsorption, smaller free energy change of the rate-limiting step (*NH to NH), and poorer hydrogen evolution reaction activity (HER, competitive reaction). This work not only highlights the potentials of Pd-based nanocatalysts for NORR but also provides new insight for the applications in NORR of other facet-orientation nanomaterials.
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http://dx.doi.org/10.1016/j.jcis.2021.05.061DOI Listing
October 2021
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